9-30-19 Is red meat back on the menu?
A controversial study says cutting down on sausages, mince, steak and all other forms of red or processed meat is a waste of time for most people. The report - which disagrees with most major organisations on the planet - says the evidence is weak and any risk to people's health is small. Some experts have praised the "rigorous" assessment. But others say "the public could be put at risk" by such "dangerously misguided" research. Red meat includes beef, lamb, pork, veal and venison - chicken, duck and game birds do not count. Processed meat has been modified to either extend its shelf life or change the taste - and the main methods are smoking, curing, or adding salt or preservatives. Pure mince does not count as processed, but bacon, sausages, hot dogs, salami, corned beef, pates and ham all do. One of the main concerns has been around bowel cancer. The World Health Organization's International Agency for Research on Cancer created headlines around the world when it said processed meats do cause cancer. It also said red meats were "probably carcinogenic" but there was limited evidence. In the UK alone, it is thought processed meat leads to about 5,400 cases of bowel cancer every year. Links with heart health and type 2 diabetes have also been suggested. The scientific consensus is eating a lot is bad for your health. The researchers - led by Dalhousie University and McMaster University in Canada - reviewed the same evidence others have looked at before. The risks reported are broadly similar to what has been suggested before - but the interpretation of what they mean is radically different. "The right choice for the majority of people, but not everyone, is to continue their meat consumption," one of the researchers, associate professor Bradley Johnston, told BBC News. "We're not saying there is no risk, we're saying there is only low-certainty evidence of a very small reduction of cancer and other adverse health consequences of reducing red meat consumption."
9-30-19 Avoiding red or processed meat doesn't seem to give health benefits
There are no health reasons to cut down on eating red or processed meat, according to a new review of the evidence. The claims, which contradict most existing dietary advice, come from a review of existing studies led by the Spanish and Polish Cochrane Centers, part of a global collaboration for assessing medical research. Numerous health bodies have said for decades that we should limit our intake of red meat because it is high in saturated fat, thought to raise cholesterol levels and cause heart attacks. More recently, both red and processed meat have been linked with cancer. In the latest review, though, the authors came to a different conclusion because they considered separately the two main kinds of research. The best evidence comes from randomised trials. In these, some participants are helped to change their diet in a certain way, such as eating less meat, and the rest aren’t. At the end, the health of the people in the two groups is compared. But such trials are costly and hard to do. According to one estimate, only about 5 per cent of nutrition studies are large, good-quality randomised trials. It is much more common to do research that just observes what people choose to eat undirected. Known as observational studies, these are notoriously open to bias and can give misleading results. Bradley Johnston of Dalhousie University in Halifax, Canada, and his colleagues first reviewed all previous observational studies looking at the health impact of eating red or processed meat. These pointed to a “very small” adverse effect on deaths, heart disease and cancer. Then they separately reviewed the 12 randomised trials that have been done in this area, and found that there was little or no health benefit for people who cut down on eating these meats. Based on these findings, the authors conclude that people should “continue to eat their current levels of red and processed meat unless they felt inclined to change them themselves”. However, they added that some might want to change their diet because of animal welfare or environmental reasons.
9-30-19 Many cancer drugs can be co-opted to treat different types of tumour
If standard treatments for cancers fail, doctors sometimes prescribe drugs that haven’t been approved for that particular cancer type. In the Netherlands, this is now being done as part of a new kind of trial, so we can get a better idea of which drugs work for what cancers – and which don’t. The results from the first 215 people show that a third of them did get some benefit from the “off-label” use of drugs. One or two had a complete remission, says Emile Voest of the Netherlands Cancer Institute in Amsterdam. Knowing about failures is just as important, because then we can prevent people who may not have long to live from being given drugs that won’t help them and could have nasty side effects. A new drug goes through an approval process for treating a specific disease, such as a certain kind of breast cancer. Once a drug is approved for one purpose, doctors can prescribe it for another purpose, although often health insurers won’t pay for off-label use. This is typically done on an ad-hoc basis. One doctor will decide what drug might help a patient who has run out of other options, and there is no systematic way of reporting the outcomes to help other doctors facing similar dilemmas. “If you have a success, you cannot share it and if you have a failure you cannot share it,” says Voest. This off-label approach can help some people, but it can also go horribly wrong. In the 1980s, some heart drugs were widely used off-label in the US. Later trials suggest that this caused 50,000 premature deaths. So Voest and his colleagues have set up a more rational way of using off-label drugs for cancers. The starting point is to sequence the whole genomes of tumours in people for whom standard treatments have failed, and to use that information to identify drugs that might help them.
9-30-19 Should the UK make childhood vaccinations mandatory?
The UK is looking “very seriously” at making vaccinations compulsory for schoolchildren in England in response to falling vaccination rates there — that’s what health secretary Matt Hancock told the Conservative party conference yesterday. “When the state provides a service to people then it’s a two-way street. You have to take your responsibilities too,” he said. His comments follow figures that emerged last week showing all routine vaccinations in England for under-5s fell last year, a decline which UK chief medical officer Sally Davies said was troubling. Embarrassingly, this year the UK lost its official “measles-free” status, after 231 cases were confirmed from January to March 2019. Hancock’s office didn’t respond to questions about what means would be used to compel people to vaccinate their children. But there are several possible options. Some countries make vaccination a condition for children going to school. Australia uses the “no jab no pay” threat of withholding benefits. But is mandating vaccinations the answer? If the UK did pursue this strategy, it would be a return to the past. In the 19th century, the government made vaccination compulsory, only later switching to a voluntary approach when the smallpox epidemic subsided and immunisation levels went up. For a long time, overall routine vaccination rates in the UK held steady at around 98 per cent. But in the case of the Measles, Mumps and Rubella (MMR) vaccine, coverage for the first dose in 2-year-old children has fallen for five years in a row and now stands at 90.3 per cent in England. The World Health Organization (WHO) has a target of 95 per cent coverage. However, the WHO makes no recommendation either for or against mandating vaccinations — it is up to countries to decide the best way of ensuring high rates, it says.
9-30-19 Female orgasm may have evolved from a trigger for ovulation
What’s the evolutionary origin of the female orgasm? A study that involved giving antidepressants to rabbits has lent support to the idea that the female orgasm may have originated from a reflex that makes some female mammals ovulate during intercourse. DThere are multiple theories regarding the function of female orgasms. Some studies have found that contractions of the uterus experienced during orgasm help transport sperm towards the egg. However, many women don’t orgasm during intercourse, and it is also common for women to conceive without climaxing. There are also simpler explanations, including that sexual pleasure encourages women to have more sex, making them more likely to conceive, or motivates them to form committed relationships, which may be beneficial for raising children. But how did the female orgasm evolve? Mihaela Pavlicev, currently at the University of Vienna in Austria, and her colleagues think that animals that ovulate during intercourse may hint at the answer. While women release an egg roughly every month, ovulation in some other mammals such as rabbits is triggered by copulation. Pavlicev and her team think the hormones and brain circuitry involved in such reflex ovulation could also be involved in generating a pleasurable climax. In 2016, they analysed 41 species of mammal. Of these, 15 species, including cats, koalas and camels, have reflex ovulation. The way these species are related across the mammal family tree suggests that this system is likely to have been present in the earliest mammal ancestors. In their latest study, the team exploited the finding that the antidepressant fluoxetine, which is sold as Prozac, reduces people’s ability to orgasm. They found that, after giving rabbits fluoxetine for two weeks, the rate of ovulation during copulation fell by a third.
9-30-19 ‘Imagined Life’ envisions the odd critters of other planets
A new book offers a science-based take on what aliens might look like. An organism is shaped by the environment in which it dwells. Considering the rampant diversity of species on Earth, just imagine the oddities that could evolve on radically different sorts of planets — perhaps black-leafed “plants” that thrive in dim light or even creatures made of metal rather than carbon. In Imagined Life, physicist James Trefil and planetary scientist Michael Summers set out on a safari through the cosmos, conjuring up the menagerie that might inhabit some of the thousands of exoplanets discovered thus far. Many of the book’s chapters explore potential life on various types of worlds, each vastly unlike Earth. Though fanciful and fun, the pair’s efforts are grounded in science and adhere to two main principles: that a small number of general rules govern the physical universe, and that Earth’s laws of physics, including thermodynamics and electricity and magnetism, apply everywhere else in the cosmos. Trefil and Summers also propose that in all but a few scenarios, natural selection drives evolution on other planets.No matter the environment, life needs a source of energy. But that energy doesn’t have to come from a star’s radiation, the authors note. An ice-smothered world or even a rogue planet floating in interstellar space could, like Earth, have oceans with seafloor hydrothermal vents driven by heat from the decay of radioactive elements in the planet’s core or from heat left over from when the planet coalesced. Whether such oceans are ice-covered or not, life in these oceans would probably evolve to take advantage of the energy-rich chemicals spewing from those vents and need to be mobile, as vents can spring into being and just as quickly fade away. Vent creatures might either resemble those living in similar ecosystems on Earth or be completely unrecognizable. On other types of worlds, life-forms could be even stranger. On a planet that has one side permanently facing its star, the most hospitable temperatures for life as we know it would exist in a thin north-south halo around the planet, where the sun always sits on the horizon. Supersonic winds would buffet the surface, scientists have suggested, so species would have to be low-slung and streamlined to minimize air resistance, the authors argue. On a rocky planet much larger than Earth, land organisms would have to deal with stronger gravity and would thus be short, squat and have strong bones or exoskeletons.
9-30-19 Ocean worlds with a thick atmosphere may be better for life than Earth
Earth may teem with life, but it might not be the absolute best cradle for it. Ocean dynamics are crucial to life here, and a new study says that a slightly different world would allow for ocean life to be even more widespread and healthy. The insight might help us find such worlds and search for signs of life there. On Earth, life in the ocean faces a tension between the availability of sunlight and nutrients. Most organisms are concentrated fairly near the water’s surface, where exposure to sunlight means that they can harvest the sun’s energy for photosynthesis. But important minerals like phosphorus tend to sink to the seafloor. Living things therefore depend on these chemicals being stirred up and buoyed to the surface by a process called upwelling. “Photosynthetic life must live at the surface where there is light, but gravity is always going to act to accumulate nutrients at the bottom of the ocean,” says Stephanie Olson at the University of Chicago in Illinois. “If you look at life in Earth’s oceans today, it is overwhelmingly concentrated in areas of upwelling for that reason.” Upwelling occurs primarily due to wind in the atmosphere pushing around the surface water — deeper water then flows upwards to fill the gaps. Olson and her colleagues simulated a series of worlds that were slightly different to Earth to figure out how various planetary characteristics could affect upwelling and other facets of ocean circulation, and how that might affect life. They found that upwelling was maximised, giving life more nutrients, on a planet not quite like our own. “For many of these parameters that you could vary to maximise upwelling and nutrient cycling in an ocean, Earth is not the sweet spot – life on other planets could be even more productive than it is here,” says Jennifer Macalady at Pennsylvania State University. “It would look greener and slimier and more seaweedy.”
9-29-19 Zantac: CVS latest to suspend heartburn drug over cancer fears
US retailer CVS has become the latest to suspend the sale of a heartburn drug being investigated for links to cancer. It follows concern in several countries over the presence of impurities in Zantac and other ranitidine products. Canada and France have already announced Zantac recalls. The US and the European Union are investigating. Health authorities say there is no immediate risk, but patients have been advised to consult a doctor who can prescribe alternatives to ranitidine. On 13 September, both the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) published their decisions to review the presence of N-nitrosodimethylamine (NDMA) in medicines containing the drug ranitidine. NDMA is classified as a probable human carcinogen (a substance that could cause cancer) on the basis of animal studies. NDMA is found in water and foods, including meats, dairy products, and vegetables, but is not expected to cause harm when ingested in very low levels, EMA says. Ranitidine products are used to reduce the production of stomach acid in patients with conditions such as heartburn and stomach ulcers. They are available over-the-counter and on prescription. CVS's announcement on Saturday said it was suspending the sale of Zantac and CVS Health brand ranitidine products "out of an abundance of caution". "Zantac brand products and CVS brand ranitidine products have not been recalled, and the FDA is not recommending that patients stop taking ranitidine at this time," the company said. Walgreens, Walmart and Rite Aid in the US had earlier taken a similar decision. Canada and France have removed the drugs from pharmacy shelves. A number of other countries have followed suit. Drug makers are also recalling products containing NDMA. Sandoz, owned by Novartis, told the BBC it was recalling "several batches of its ranitidine-containing medicines". The recalls were "under way or pending" in Australia, Austria, Belgium, Canada, Croatia, the Czech Republic, Denmark, Finland, Germany, Hungary, Macedonia, Portugal, Slovakia, Slovenia, Sweden, Switzerland and the US. Apotex also said it was recalling ranitidine tablets in the US.
9-29-19 Why researchers are obsessed with studying chickadees
In the fall, chickadees hide roughly 80,000 individual seeds, then use their memory to retrieve them come winter. Despite weighing less than half an ounce, mountain chickadees are able to survive harsh winters complete with subzero temperatures, howling winds, and heavy snowfall. How do they do it? By spending the fall hiding as many as 80,000 individual seeds, which they then retrieve — by memory — during the winter. Their astounding ability to keep track of that many locations puts their memory among the most impressive in the animal kingdom. It also makes chickadees an intriguing subject for animal behavior researchers. Cognitive ecologist Vladimir Pravosudov of the University of Nevada, Reno, has dedicated his career to studying this tough little bird's amazing memory. Writing in 2013 on the cognitive ecology of food caching in the Annual Review of Ecology, Evolution, and Systematics, he and coauthor Timothy Roth argued that answers to big questions about the evolution of cognition may lie in the brains of these little birds. In July, at a meeting of the Animal Behavior Society in Chicago, Pravosudov presented his group's latest research on the wild chickadees that live in the Sierra Nevada mountains. He and his graduate students were able to show for the first time that an individual bird's spatial memory has a direct impact on its survival. The team did this by building an experimental contraption that uses radio-frequency identification (RFID) technology and electronic leg bands to test individual birds' memory in the wild and then track their longevity. The researchers found that the birds with the best memory were most likely to survive the winter. Knowable Magazine spoke to Pravosudov about what his research means for our understanding of memory and cognition. This conversation has been edited for length and clarity.
9-27-19 Vaping-deaths crisis envelops Juul
The future just got a lot hazier for Juul, said Jennifer Maloney in The Wall Street Journal. The controversial e-cigarette maker blamed by federal health officials and anti-tobacco groups “for a sharp rise in teenage vaping” announced this week that its CEO, Kevin Burns, is stepping down. The company is also suspending all broadcast, print, and digital advertising in the U.S. and ceasing its lobbying effort against a proposed federal ban on flavored e-cigarettes. The moves come a day after prosecutors in California launched a criminal probe into the role that Juul’s marketing has played in a recent rash of respiratory illnesses resulting in at least eight deaths. Altria’s $12.8 billion wager on Juul last winter was supposed to future-proof its business, said Sarah Halzack in Bloomberg.com. When Altria bought its stake, Juul was successfully pitching itself as a healthier alternative to smoking. Now the bet on Juul seems more like “a cautionary tale for any stalwart in a mature industry that is looking for a savior in the form of an upstart.” It’s probably not a coincidence that Altria’s plan to merge with Philip Morris International—the overseas business it spun off in 2008—got called off this week, too. Who wants to join forces with Altria right as “U.S. regulators appear ready for a crackdown?”
9-27-19 School start times: Why teens are so sleepy
Let the kids sleep, said Scott Maxwell in the Orlando Sentinel. Nationally, nearly 9 out of 10 high schools begin classes before 8:30 a.m., and 10 percent before 7:30, forcing tired teens to get out of bed without sufficient sleep. Here in Orange County, Fla., “buses pick up kids more than an hour before dawn” and classes start at 7:20 a.m. This early-bird schedule flies in the face of findings by the American Academy of Pediatrics that 87 percent of America’s high school students are chronically sleep deprived, and that high schools and middle schools should start no earlier than 8:30 a.m. This is “hardly a trivial matter,” said the Jacksonville, Fla., Times-Union in an editorial. Research shows that “teens who don’t get enough sleep are more likely to be overweight and depressed” and to smoke, drink and use drugs, and do poorly in school. Teenagers’ “biological bedtime” is around midnight, “and it just makes no sense to fight Mother Nature.” Enough study, said The Press of Atlantic City in an editorial. Since the AAP’s 2014 report, the Centers for Disease Control and Prevention, the American Medical Association, “and just about every other credible medical science organization” have come out in support of later start times. The Brookings Institution found that later school start times were followed by “a significant increase” in test scores. One New Jersey school district moved all start times to 8:30 and found “reduced absenteeism and lateness, and teachers reported students were more alert and ready to learn.” The evidence is in, and it leads to only one conclusion: “Start school later.”
9-27-19 A mosquito experiment mishap?
Genetically modified mosquitoes that were released in Brazil with the aim of reducing wild populations may have made the disease-bearing pests more “robust,” according to new research. From 2013 to 2015, biotech company Oxitec introduced hundreds of thousands of genetically tweaked mosquitoes—engineered to produce offspring that wouldn’t make it to adulthood—into the city of Jacobina. Overall mosquito numbers declined during the trial period. But a new study by researchers from Yale University found that the population started to rebound after 18 months. More troubling, the genomes of the modified insects showed up in wild mosquitoes. “The claim was that genes from the release strain would not get into the general population because offspring would die,” senior author Jeffrey Powell tells The Scientist. “That obviously was not what happened.” Powell and his team speculate that the added genetic diversity could result “in a more robust population.” Oxitec says the Yale study contains “false” and “unsubstantiated” claims and has called for a retraction. The controversy could deter local communities from giving the green light to future open-field trials.
9-27-19 What ‘organic’ really means
- Milk: A USDA Organic seal indicates the dairy cows have access to sunlight, shade, shelter, clean bedding, fresh water, and outdoor exercise. They can’t be given antibiotics or hormones, and their feed must be grown without pesticides or GMOs. Though they also must get a third of their calories from grazing, only seals that say American Grassfed or PCO Certified 100% Grassfed ensure they regularly roam clover pastures.
- Eggs: Organic eggs must come from hens that aren’t pumped full of antibiotics and are raised on organic feed. But “organic” doesn’t mean that the chickens roam freely—unless the packaging also says “pasture-raised.”
- Bread: Like other packaged products, bread labeled “organic” can’t contain any preservatives, artificial sweeteners, or other prohibited ingredients. Organic bread doesn’t always contain whole grains, though, so sometimes it’s not the nutritious choice.
9-27-19 Vaping-related illness reports have surged to 805 from 46 U.S. states
Twelve people have now died from lung injuries tied to e-cigarettes. The number of vaping-related lung injuries has soared in the last week, up to 805 from 530, the U.S. Centers for Disease Control and Prevention reports. Forty-six states and one territory, the U.S. Virgin Islands, have been affected. Twelve people in 10 states — California, Florida, Georgia, Illinois, Indiana, Kansas, Minnesota, Mississippi, Missouri and Oregon — have now died. “This is something pulmonary critical care physicians are experiencing across the country right now,” said Albert Rizzo, the chief medical officer of the American Lung Association, on September 24 during congressional testimony on the outbreak before the House Committee on Oversight and Reform. The CDC updated the case count on September 26, but hasn’t released new information on why e-cigarette users are developing life-threatening lung illnesses. At the committee hearing, Anne Schuchat, CDC’s principal deputy director, described the agency’s ongoing investigation as challenging because of the large number of states involved, the diversity of e-cigarette products, the wide array of ingredients in the devices and the potential involvement of substances like marijuana. Plus, “users can modify the products, and the heating process can also influence the types and amounts of chemicals a user is exposed to,” Schuchat said. “The identification of the cause or causes for the outbreak may take substantial time and continuing effort.” These lung illnesses have left patients, many of whom were young and healthy, gasping for breath and requiring hospitalization (SN: 9/6/19). As injuries surge and with recent research finding that vaping among teens continues to climb (SN: 9/18/19), there have been federal and state calls to limit the use of flavored e-cigarettes, which are particularly popular among youth, or even ban vaping.
9-27-19 Mice fidget. Those motions have big effects on their brains
Extra movements may shape thinking, a study hints. Survey any office, and you’ll see pens tapping, heels bouncing and hair being twiddled. But jittery humans aren’t alone. Mice also fidget while they work. What’s more, this seemingly useless motion has a profound and widespread effect on mice’s brain activity, neuroscientist Anne Churchland of Cold Spring Harbor Laboratory in New York and colleagues report September 24 in Nature Neuroscience. Scientists don’t yet know what this brain activity means, but one possibility is that body motion may actually shape thinking. Researchers trained some mice to lick a spout corresponding to an area where a click or a flash of light originated. To start their task, mice grabbed a handle and waited for the signal. As the mice focused on their jobs, researchers used several different methods to eavesdrop on nerve cell behavior in the animals’ brains. All the while, video cameras and a sensor embedded on a platform under the mice picked up every move the rodents made — and there were a lot. Mice wiggled their noses, flicked their whiskers and fiddled their hind paws while concentrating on finding the sound or light, the team found. Those fidgets showed up in nerve cell activity. When a whisker moved, for instance, nerve cells involved in moving and sensing sprang into action. Fidgets predicted a big chunk of neural behavior, mathematical models suggested. Mice’s fidgets even had stronger effects on brain activity than did the task at hand, the researchers report. These movements reflect “unknown priorities of the animal,” the researchers write. One tantalizing possibility is that body motion — and its big effect on brain activity — may be part of the thinking process.
9-26-19 DR Congo: Vaccine campaign for world's largest measles outbreak
More than 800,000 children are to be targeted for vaccination in the Democratic Republic of Congo, after a measles outbreak killed more than 3,500 people this year. The World Health Organization (WHO) and the Congolese government aim to carry out the emergency programme across the country in slightly more than a week. The WHO says the epidemic is the world's largest and fastest moving. It has killed more Congolese people this year than Ebola. Despite previous rounds of immunisations, the disease has spread to every part of the country. Lack of routine access to vaccinations and healthcare has contributed to the problem. "The DRC is experiencing a dire situation because too many children were missed by routine immunisation," said Dr Deo Nshimirimana, WHO representative to the DR Congo. "[The outbreak] is deadly because the case management is not there," he told the BBC's Newsday programme. "We don't have the resources really to prevent the disease and also to try to prevent the deaths so... measles is very deadly in this country. We are trying our best really to prevent the disease, but also to try to have resources to get supplies so that we can manage the cases." Every one of the country's 26 provinces has reported cases of measles and is battling to control this outbreak, which the ministry of health declared on 10 June. The campaign aims to vaccinate around 825,000 children in 24 regions, over a period of nine days, the agency said. "As of 17 September, a total of 183,837 suspected measles cases (5,989 confirmed) had been reported in 192 of the 519 health zones nationwide, including 3,667 deaths - which exceed the number of deaths due to Ebola. Nearly all the deaths have been children," the WHO said in a statement. In the country's east, Ebola has claimed more than 2,100 lives since erupting in August last year, and is the second largest outbreak of the disease on record. The largest was the epidemic that ravaged parts of West Africa from 2014 to 2016, killing more than 11,000 people.
9-26-19 Around half of your chances of career success comes down to sheer luck
How much of a person’s career success is the result of sheer luck? About half, depending on what field you’re in. Roberta Sinatra at the IT University of Copenhagen, Denmark, and her colleagues set out to measure what role luck and individual ability play in the success of creative works, including films, songs, books and scientific research papers. They used this as a proxy for career success. The researchers looked at works from more than 4 million people across the publishing, film and music industries, as well as 15 scientific fields. They quantified impact based on the number of reviews that movies or books had accrued on IMBD or Goodreads respectively, and the number of times songs had been played on LastFM. The team also looked at 87.4 million research papers on the Web of Science database, measuring an article’s impact based on the number of times it was cited within a decade of being published. By looking at the random fluctuations in the timing and magnitude of successful work, the team was able to come up with a crude estimate of luck different careers typically involve, using a measure called a randomness index, R. An entirely luck-based activity such as roulette would have an R score of 1, for example. Luck appeared to have a relatively consistent effect across all the fields they studied, with a maximum difference of just 5 per cent. In the music industry, electronic music artists needed the most luck (0.546) and classical musicians the least (0.507), while in the film industry movie producers needed the most luck (0.545). Within science, success in astronomy involved the most luck (0.55) while computer science was associated with the least (0.517).
9-26-19 A mouse’s metabolism may follow circadian rhythms set by gut bacteria
The microbes control when fat gets absorbed from food, a study finds Mice (and maybe people) may metabolize food according to daily, circadian rhythms set by gut bacteria. Microbes in the small intestine of mice rhythmically dictate when fat is taken up by cells that line the organ, researchers report. The study, described in the Sept. 27 Science, details how gut microbes influence a host’s metabolism. If the findings carry over to people, the research may give clues to why jet lag and night-shift work, which can throw off circadian rhythms, often lead to obesity, diabetes and other health problems. Researchers knew that human cells have molecular clocks that time 24-hour circadian cycles of metabolism (SN: 11/8/18), and that gut microbes in the colon follow their hosts’ biological beat (SN: 10/16/14). But the new study finds that, at least in the small intestine, microbes can set rhythms for host cells to follow. That work was done in mice, but the process may work similarly in people. The new research “is helping us appreciate just how intertwined are the metabolisms of the microbiota and their mammalian hosts,” says microbiologist and immunologist Andrew Gewirtz of Georgia State University in Atlanta who was not involved in the work. “It’s a very intimate interaction, regulating things as basic as circadian rhythms, which was quite a surprise.” Previous research has found that mice raised without any microbes don’t gain excess weight, even when fed a high-fat diet. Those “germ-free mice” also lacked strong circadian rhythms in cells lining the rodents’ small intestines, microbiologist Lora Hooper of the University of Texas Southwestern Medical Center in Dallas and colleagues found. Giving the mice intestinal bacteria, however, strengthened those circadian rhythms. It’s unclear which microbes are important for this process.
9-25-19 Deliver us from evil: How biology, not religion, made humans moral
Our survival instinct should undercut morality – but our mammalian brains pulled off an amazing evolutionary trick, says neurophilosopher Patricia Churchland. A SIMPLE interpretation of biological evolution says that nature selects for selfishness. Always. Selfish genes increase survival, so are the ones that get passed on. If altruistic genes happen to poke their heads up, they are quickly whacked. In this reading, the desire to do good by others must be taught – usually with the threat of punishment by a wrathful God, censorious parent or nosy cop. The only underlying motive for any altruism is fear. But here is the thing: all highly social mammals sacrifice their own needs for others, as do birds. In the first instance, the beneficiaries are offspring, but they can also be mates, kin and friends. Chimpanzees reconcile after a squabble and console each other after a defeat, rats share food with another rat pal, and wolves, fully aware of the danger, defend each other against a grizzly bear. Male marmosets and chimpanzees have been observed to adopt orphaned young to whom they have no genetic connection. Early-hatched bluebirds help feed and guard their siblings in later broods. Humans do variants of all these things. Charles Darwin puzzled over this selflessness in his 1871 book The Descent of Man. Where does our moral sense, or conscience, something that seems to fly in the face of biology, come from? A century and a half on, advances in our understanding of evolution and neuroscience are serving up some intriguing answers. Among animals, the self-sacrifice of mammals and birds is unusual, both in its breadth and its flexibility. Other social species – insects such as termites, for example – have little behavioural flexibility. Loners such as reptiles and amphibians tend not to exhibit selflessness at all. A salamander will continue to forage rather than defend her brood. Although garter snakes do give birth to live young, hinting that some parenting might be forthcoming, the mother snake blithely abandons her 50 or so squirming babies to fend for themselves. Her brain simply isn’t made for offspring care. But mammals and birds seem wired for love and affection. Ethologists such as Frans de Waal have documented empathic behaviour and social emotions among mammals in detail: pleasure when kith and kin are safe and fed and close by; pain and anxiety when they are threatened or suffering or far away.
9-25-19 Rockland’s measles outbreak is over, but U.S. elimination status is still at risk
Health officials still have their eye on measles cases in nearby counties New York state’s measles outbreak, which has been going on so long it raised fears the disease would regain a foothold in the United States, appears to be on the verge of finally ending. Officials in Rockland County, N.Y., on September 25 declared their outbreak over. The New York State Department of Health is still keeping a close eye on whether any new measles cases occur in two nearby counties that are considered part of the outbreak that began in Rockland on October 1. The state’s measles outbreak is the longest-running since the disease’s elimination in the United States in 2000 (SN: 4/24/19). If the virus is determined to be circulating in an area for a year or more, the disease is considered endemic, and that elimination status, a major public health achievement, is lost. That milestone occurs October 2, according to the U.S. Centers for Disease Control and Prevention. In Rockland County, there were 312 confirmed measles cases, the last of which occurred August 13. Most of those cases were in people who hadn’t been vaccinated against the disease. The last measles cases in Sullivan County and Orange County, New York, were reported on August 15 and August 19, respectively. A measles outbreak can be declared finished 42 days after the date that the last person with measles developed a rash. That means if there are no new cases, the New York state outbreak could come to an end just before the deadline for losing elimination status. So far this year, measles has reestablished itself in four countries where it previously had been eliminated: the United Kingdom, Greece, Albania and the Czech Republic. In a written statement, the CDC said the agency “is hopeful that the U.S. will maintain its measles elimination status,” but that “we are not out of the woods yet.”
9-25-19 50 years ago, scientists warned of marijuana’s effects on the unborn
Excerpt from the September 27, 1969 issue of Science News New research hints that marijuana may have serious physiological effects that should make it, like cigarettes, carry a warning … The possibility that marijuana is teratogenic, causing damage to unborn children, is a specter that as yet cannot be put down … [T]here is already some information indicating that THC readily crosses the placenta and enters the fetus. Marijuana use by pregnant women is on the rise, with some using it to treat morning sickness (SN Online: 09/11/18). In a U.S. national survey that included more than 4,000 pregnant women, marijuana use roughly doubled between 2002 and 2017 from 3.4 percent to 7 percent, researchers reported June 18 in JAMA. And in a different study in the same issue, self-reported marijuana use by pregnant women was linked to a greater risk of premature birth. A recent study in rats, presented at Experimental Biology 2019 in Orlando, Fla., found that cannabis may change the nerve connections in the brain’s hippocampus, which plays a role in learning and memory.
9-25-19 Ancient grains are misnamed and their health benefits are unconfirmed
#FactsMatter | Wellness influencers extol the virtues of so-called ancient grains. But are they really better for us, asks James Wong KHORASAN, teff, emmer and amaranth. No, these aren’t planets in the next Star Wars movie, but some of the growing range of wheat alternatives that are increasingly filling supermarket shelves (and “wellness guru” Instagram feeds) everywhere. Said to be untouched by modern plant breeders, who have apparently rendered wheat an unhealthy option, these “ancient grains” can supposedly transform your health. But what exactly are these foods, and are they as beneficial as claimed? Here’s the first thing: ancient grains are often anything but. Take quinoa. The seeds of this South American plant are thought to have been bred for human consumption as recently as 3000 years ago, making it only a third of the age of bread wheat. Even some of the oldest members of the wheat group, such as einkorn and emmer which were first bred 10,000 years ago, only predate bread wheat by a millennium or so. In fact, many ancient grains aren’t even true grains (the seeds of grass plants), just a motley crew of seeds from a range of plant families and a few more unusual rice and maize cultivars. With no science behind this definition, it seems to be employed as a catch-all marketing term used to describe anything that isn’t bread wheat, regardless of its actual age, how intensively it has been bred or whether or not it is even a grain. Semantics aside, are they more nutritious? This seems to have been investigated only very recently. With most of the best studies published in the past five years or so, the health claims appear to predate much of the evidence. Studies examining the nutritional composition of ancestral wheats like emmer, einkorn and khorasan compared with modern bread wheat tend to have found a wide variation between samples, which makes comparing them tricky.
9-25-19 Ancient European megastructures may have been community centres
The mysterious megastructures of ancient eastern Europe were hubs of social and political decision making, but their role in centralising political control may have led to the downfall of these societies. Tripolye culture spread from modern-day Moldova and Romania into Ukraine and is known for its finely crafted pottery and huge settlements. These large settlements, which were home to up to 10,000 inhabitants, could stretch hundreds of hectares across and are the largest in prehistoric Europe. The settlements emerged around 4100 BC and appear to have stopped being built around 3600 BC. Most are buried today. From 2009, sophisticated imaging tools revealed that these settlements were also home to rectangular buildings that were bigger than houses and typically situated in open spaces in the settlements. In comparison to homes, which were around 15 metres long and 7 metres wide, the megastructures were up to 65 metres long and 10 metres wide. Archaeologists recently discovered megastructures in a giant Tripolye settlement in Ukraine, called Maidanetske, but the purpose of them has been unclear. To find out what they were used for, Robert Hofmann at Kiel University, Germany, and his colleagues compared the structures of Maidanetske to more than 100 other megastructures in 19 other ancient European settlements. Comparing the maps of these settlements, Hofmann and his colleagues determined that the megastructures, typically made from clay-covered split wood and log timbers, occupied important positions. While houses were lined up in concentric rings, megastructures were built within the ring corridor, at pathways or on the outskirts of the settlement. Some were in open plaza-like spaces. The megastructures look like community centres that serve several different purposes in other cultures, including economic and political decision-making and religious functions, says Hofmann.
9-25-19 Losing genes may have helped whales’ ancestors adapt to life under the sea
The loss could have smoothed ancient cetaceans’ land-to-water transition 50 million years ago. Like stripping down to swim, the ancestors of whales and dolphins may have shed some genes during their transition from being landlubbers to aquatic dwellers. Ancestors of orcas, bottlenosed dolphins and other cetaceans lost function of at least 85 genes as the animals adapted to live full time in water, researchers report September 25 in Science Advances. Scientists compared DNA of whales and dolphins with that of other mammals to find 236 genes missing from cetaceans. Of those missing genes, 85 are still present in hippopotamuses, cetaceans’ closest relatives, suggesting that the genes were lost during the land-to-water transition about 50 million years ago. Cetaceans may have adapted to diving by jettisoning genes involved in regulating blood pressure and blood clotting, and in repairing DNA. DNA undergoes damage from cycles of low and high oxygen as animals dive to deep water and resurface again. One of the lost genes, POLM, encodes a DNA repair enzyme that is error-prone even under the best of circumstances, so getting rid of it may have given cetacean ancestors an advantage. “We think that by losing the sloppiest protein involved, you probably increase the fidelity of DNA repair,” says evolutionary genomicist Michael Hiller of the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, Germany. Giving the heave-ho to other genes involved in lung function may ultimately have helped whales and dolphins avoid damage when their lungs temporarily collapse during deep dives.
9-25-19 Fossilised microbes from 3.5 billion years ago are oldest yet found
We have finally uncovered hard evidence that 3.5 billion year old rocks in Australia really do contain fossils of the oldest known microorganisms. The findings put to bed a debate that has raged for years and may even enlighten us as to how some of Earth’s earliest life forms functioned. Raphael Baumgartner at the University of New South Wales in Australia and his colleagues looked at rocks in the Pilbara region of Western Australia. This area contains some of the oldest preserved rocks on Earth. Of the three most important sites, the Dresser Formation is the oldest, with rocks that are 3.48 billion years old. The Dresser Formation appears to contain layered structures called stromatolites. These are known to form when microbes grow into thin layers, which then become covered in sediment, only for another layer of microbes to form on top, and so forth. However, many researchers are not convinced that the rock structures really are stromatolites, arguing that they could have formed without life being present. Baumgartner’s team drilled into the rocks to get the best-preserved samples. They found many layers that looked like stromatolites. These contained “exceptionally preserved organic matter”, says Baumgartner, including strands of the sort seen when microbes form slimy layers called biofilms. Multiple chemical analyses indicate that the organic matter came from living organisms. “We have found smoking gun evidence for some of the earliest life on Earth,” says Baumgartner. “There are no convincing organic matter or microbial remains older than ours.” There are plenty of claims of older fossils, or of chemical traces of life, some dating to over 4 billion years ago. But none has found widespread acceptance. The organic matter Baumgartner’s team found was mostly trapped inside a mineral called pyrite or fool’s gold, which is based on iron and sulphur.
9-25-19 Experimental diabetes drug may lower blood sugar and reduce obesity
An experimental drug for treating type 2 diabetes appears to have many beneficial effects. Experiments in animals found that the drug reduces blood sugar levels and the amount mice eat, while maintaining muscle mass and increasing bone density. Type 2 diabetes develops when the body fails to respond to insulin released to lower blood sugar levels. The resulting high blood sugar levels can seriously damage many parts of the body. It’s estimated that 370 million worldwide have type 2 diabetes, and this number is expected to double by 2030 as obesity levels keep rising. There are already some drugs for treating type 2 diabetes, but better ones are needed. Metformin is widely prescribed to lower blood sugar, for instance, but it does not usually cause weight loss and some people stop taking it because of side effects such as diarrhea and flatulence. Mark Febbraio at Monash University in Australia and his colleagues have developed an alternative drug based on signalling proteins. These bind to a receptor called gp13 found on many cells in our body and that are known to have beneficial effects on the metabolism. To create the drug, the team combined parts of two different human signalling proteins and made various other tweaks to create a designer signalling protein called IC7Fc. When they injected the protein into obese mice, it had multiple beneficial effects including lowering blood sugar levels. The animals also ate less, lost weight and had increased bone density. This weight loss was due to fat loss; there was no decline in muscle mass. By contrast, obese mice that were simply fed less without getting IC7Fc lost muscle mass as well as fat. In people, losing weight can be enough to restore normal blood sugar levels. The drug also prevented the build-up of fat in the liver. Initial experiments in monkeys seem to back up the findings.
9-25-19 Screen time: How smartphones really affect our bodies and brains
If you believe the headlines, screens are supposed to warp our skeletons, damage our mental health and alienate us from our families. But the evidence paints a more nuanced picture. YOU’LL get square eyes!” my mother used to say as I sat for hour after hour glued to the TV. I ignored her, of course. It was just something parents said. Fast-forward a few decades and now I’m the parent. My 5-year-old lives in a world where screens aren’t fixed pieces of furniture, but lie around on the kitchen table, on the sofa, by the bed, constantly accessible. You can’t even avoid them by going outside. “Screens are not only in our pockets, they’re on billboards, buses and bins,” says Tim Smith, a psychologist at Birkbeck, University of London. The concerns have multiplied with the screens. In the past decade, we have heard that they will rewire our brains, strip us of cognitive abilities and damage our mental health. Many of us feel more distracted by them, feeling grumpier, guiltier and more tired as a result. The list of ills makes square eyes sound benign. So should we take these concerns more seriously? Given the amount of time so many of us spend with our lit-up devices, it is an important question. The trouble is, many of the most emphatic answers are the least reliable. Smartphones and tablets are not only TVs, they are chat rooms, shopfronts, banks and photo albums. We use them to work and play, to record physical activity and monitor sleep. We can look up peer-reviewed papers or scroll through anti-vaxxing forums, crucial distinctions that disappear when we use the umbrella term “screen time”. As the fears grow and the debate becomes ever more heated, it’s time to separate the proven health advice from the hyperbole.
9-25-19 Should people with mental health conditions be drugged to stand trial?
A US trail is bringing the questionable practice of forced medication into the spotlight – but in the UK and elsewhere voices are growing for its use, says Laura Spinney LLOYD BARRUS stands accused in Montana of five federal crimes, including accountability to deliberate homicide relating to the death of a police officer. The charges have to do with an incident in 2017 that appears to have started in a dispute about a traffic violation. By the end of it, both Barrus’s son and Broadwater County sheriff’s deputy Mason Moore were dead. Barrus has yet to stand trial. In 2018, psychiatrists diagnosed him with multiple mental health conditions, including delusional disorder, and concluded that he was unfit to stand trial. In April, a judge ruled that he should be forcibly medicated, so he could give his account of the incident in court. His lawyers are appealing to Montana’s supreme court. The case throws a public spotlight on a grey area of ethics and the law. Forcing someone to take medication so that they can stand trial and potentially be sent to prison, or even in some US states to their death, may seem barbaric. But when the question is how to balance the fair treatment of vulnerable defendants and the public right to protection, there are no easy answers. The judge in the Barrus case was exercising her right under a controversial 2003 US Supreme Court ruling, Sell v. United States, to overrule a defendant’s refusal to be medicated. It comes with strict criteria: that the case is important enough, that the drugs are both medically appropriate and “substantially likely” to achieve the desired effect, and that there is no less invasive method of achieving the same end. In the UK, the 1983 Mental Health Act allows forcible medication of people deemed at risk of harm to themselves or others. If this has the side effect of making someone fit to stand trial, so be it. Increased use of the practice is now under discussion as part of ongoing legal reforms. One concern in the UK is that the bar to be declared incompetent to stand trial is so high that it may not protect vulnerable people from an unfair trial. Another is that the price for being protected is often indefinite incarceration in a psychiatric facility. Forced medication may actually be in some defendants’ interests.
9-25-19 Prehistoric baby bottles found in Bronze and Iron Age sites in Germany
THREE small spouted drinking vessels collected from ancient graves of small children may have been used as prehistoric baby bottles. The artefacts, found in Bronze and Iron Age settlements in Germany, contain traces of animal milk. The pots are a window on a key stage in human history when there was rapid population growth aided by the ability to nourish babies with something other than human breast milk, says Julie Dunne at the University of Bristol, UK. “They bring you very close to the past, to prehistoric mothers and children.” Over a hundred spouted clay vessels in assorted shapes have been found in various European prehistoric settlements dating as far back as 7000 years. The idea that such vessels were used for babies is long-standing, especially as a few were found in infants’ graves, but an alternative idea is that they were for feeding watery foods like gruel to sick or older people. Dunne’s team analysed chemical residues from spouted pots that were found in the graves of three young children, which dated back around 3000 years. Two vessels had fatty acids found in milk from goats, sheep or cattle. The third had a profile suggesting it had contained both animal and breast milk at various times (Nature, DOI: 10.1038/s41586-019-1572-x). The vessels could have been used to wean babies off breast milk or given to those whose mothers had died, says Dunne. The appearance of animal milk in children’s diets is important because when women are breastfeeding, they are less able to get pregnant. Modern hunter-gatherers tend to breastfeed their infants for up to five years, which then spaces out their children. “They’re on the go, they don’t want to have to carry and manage lots of babies,” says Dunne.
9-25-19 Baby bottles may go back millennia in Europe
Early farmers used vessels with spouts to wean infants, scientists suggest. Three spouted vessels from graves in ancient European cemeteries may have come from the mouths of babes. Chemical signs of nonhuman animal milk in the artifacts suggest that the small clay containers, previously found in three children’s graves in southeastern Germany, represent early versions of baby bottles, researchers report. Spouts on these types of pots would have delivered milk to babies and young children during weaning, biomolecular archaeologist Julie Dunne of the University of Bristol in England and colleagues conclude September 25 in Nature. Two of the graves where the newly analyzed vessels were found date to between around 2,800 and 2,450 years ago. The third burial dates to between about 3,200 and 2,800 years ago. Two of the youngsters died at around age 1 or 2; the other might have been as old as 6. Similar clay vessels with spouts, some of which are shaped as animals, date to as early as 7,500 years ago in Europe. Such finds have been recovered at early farming villages, often in children’s graves. Possible uses of these objects, say for feeding babies or perhaps elderly or sick adults, have been unclear. Dairying in Europe began at least 6,000 years ago (SN: 1/29/03). Chemical markers of dairy fats from the fresh milk of animals such as cows or goats appeared in all three vessels, the team found. Pig or possibly human milk may have been mixed with the contents of one container. Milk from cows or other domesticated creatures could have supplemented but not totally replaced the nutritional value of mothers’ milk as infants were removed from breastfeeding, the scientists say.
9-25-19 Prehistoric babies fed animal milk in bottles
Prehistoric babies were bottle-fed with animal milk more than 3,000 years ago, according to new evidence. Archaeologists found traces of animal fats inside ancient clay vessels, giving a rare insight into the diets of Bronze and Iron Age infants. The discovery suggests milk was given to infants to supplement breast feeding and could have contributed to a baby boom. The type of milk is unknown, but goats or cows are likely suspects. This is the first direct evidence for how prehistoric infants were fed, said Dr Julie Dunne of the University of Bristol, adding that the practice could have boosted fertility. "It's so nice to have that window on the past and think about how mothers and how families were dealing with bringing up children several thousand years ago," she told BBC News. "The fact that we can feed human babies animal milk for the first time means essentially that prehistoric women can have more babies, which leads to a massive population increase, which sets us on the pathway to how we live today." Some 7,000 years ago in Neolithic Europe, human lifestyles underwent a profound shift. The hunter gatherer lifestyle vanished as people grew crops and domesticated animals. Humans began consuming dairy products about 6,000 years ago, but very little is known about the diet of ancient infants. Past evidence has suggested prehistoric infants were likely given some sort of baby food in addition to breast milk after six months, but their diet was unknown. Archaeologists turned to ceramics for the answer, specifically spouted pottery vessels dating back to more than 5,000 years ago. They tested the contents of three small "bottles" that had been buried alongside infants in graves from the Bronze Age and Iron Age (between 1,200 and 450 BC). Molecular fingerprints revealed fats from animal products, including fresh milk. Giving milk in this way would have had its risks as the hard-to-clean bottles could have exposed babies to infection. But switching away from breast feeding may have had a fertility effect, contributing to the population explosion around this time.
9-25-19 The first Americans: The untold story of the pioneers of the New World
The Americas were the last continents conquered by humanity. Now we know that those who settled there were a hardy group that first had to survive in the Arctic SOME 15,000 years ago, a small band of pioneers stood on the threshold of a new world. To the south were the Americas, 40 million square kilometres of virgin territory including wide-open prairies, dense rainforests and high mountain chains. An epic journey was about to begin – but only because a remarkable adventure had just ended. Before these original American frontiersfolk ventured south, their forebears had spent millennia scratching a living in the desolate regions just south of the Arctic circle. Once they had arrived in the north, global temperatures plunged and the climate became bleaker still. Faced with worsening conditions, these original pioneers stayed put, spending thousands of years isolated from the rest of humanity. Their fate is now coming to light, and it is clear that something remarkable happened during those missing years. The people who would eventually conquer the Americas evolved some unusual adaptations to survive, and it turns out that this genetic legacy can help trace their descendants today. We don’t know exactly when humans first reached the New World. The consensus is that the first Americans arrived fairly recently, about 15,000 years ago. It is also widely believed that they did so via Beringia – an area centred on the Bering Strait between Siberia and Alaska, which was dry land at that time. This implies that the story of the first Americans began with a subarctic odyssey. Whereas Europe and Asia has been home to hominins for almost 2 million years, it seems none of the earliest inhabitants – including Homo erectus, Neanderthals and Denisovans – strayed much above 55° north, roughly in line with the top of what are now Ireland and Kazakhstan. “There’s every reason not to do it,” says Ben Potter at the University of Alaska Fairbanks. It isn’t just cold. There aren’t as many animals at higher latitudes, making hunting difficult.
9-25-19 The story of how humans got to the Americas isn’t a simple one
The New World wasn’t conquered by a single group of people - different populations migrated and interbred in a tangled web. This is the new normal for human evolution. “CLOVIS First” was once the rallying call of archaeologists studying humanity’s settlement of the Americas. It referred to the idea that the prehistoric people who made the distinctive Clovis bone and ivory tools must have been the first human to enter the New World, about 13,000 years ago. Now we know better. Like much of the received wisdom about human evolution, the peopling of the Americas has been subject to revision in recent years. New discoveries leave no doubt that people arrived earlier than 13,000 years ago, possibly far earlier. Some of the evidence for occupation is still hotly contested. Who the pioneers were is also proving difficult to pin down. However, there seems little doubt that they entered the last continental landmass to be inhabited by humans from the north. They came via Beringia, an area centred on the Bering Strait between Siberia and Alaska. These people also didn’t simply migrate through this subarctic region. They took up residence there and became isolated from the rest of humanity for thousands of years, as the world was plunged into an icy period. These were the first people known to inhabit subarctic regions. We are now starting to piece together the story of how they survived in this harsh environment, and how that experience shaped them genetically and physically (see “The first Americans: The untold story of the pioneers of the New World”). Intriguingly, we can track some of their genetic adaptations right down into Central and South America, where they could explain puzzling anomalies found in ancient human remains and among modern indigenous Americans. “Clovis First” has now been comprehensively refuted and a new picture is emerging. The conquest of the New World didn’t entail a single group of people marching from north to south. There were different populations, ebbing and flowing and interbreeding.
9-24-19 Disabling one protein might one day lead to a cure for the common cold
Rhinoviruses couldn’t replicate in mice and human cells engineered to lack SETD3. An uncommon way of thinking may be bringing scientists one step closer to a cure for the common cold. Researchers have identified a key protein in humans that some viruses use to multiply inside of human cells. Disabling that protein, instead of attacking the virus itself, may prevent infections from spreading. In mice and human cells engineered to lack this protein, the viruses couldn’t replicate, Jan Carette, a microbiologist at Stanford University School of Medicine, and colleagues report September 16 in Nature Microbiology. “It’s not quite a cure for the common cold, but it’s an interesting step forward,” says Ellen Foxman, an immunologist at Yale School of Medicine who was not involved in the study. Colds are the most common infectious disease in humans. On average, adults catch a cold two or three times each year, while children get the sniffles even more often (SN: 2/12/09). Any one of a few hundred viruses, including rhinoviruses, can cause these infections. That fact — and because these viruses can mutate quickly to become resistant to drugs — makes it difficult to find a cure. So researchers at Stanford and the University of California, San Francisco focused on the human host rather than the virus. Viruses hijack cells and rely on humans’ own cellular machinery to make more virus and sicken their host. The team wanted to see if it could identify human genes that make the proteins that many viruses hijack in order to replicate. Using the gene-editing tool CRISPR, Carette and colleagues systematically deleted chunks of DNA to build a library of human cells, each missing one gene and therefore unable to make that gene’s corresponding protein. The researchers then infected the cells with two types of viruses, one that causes colds and another that has been linked to neurological diseases.
9-23-19 AI is learning to diagnose schizophrenia from a smartphone video
Speaking into your smartphone for 2 minutes could reveal whether you have a mental health condition. That is according to the developers of an app that analyses facial expressions and speech to diagnose schizophrenia. The company behind the app, AICure, hopes that it could be used to better support and monitor people with schizophrenia, and eventually those who have other mental health conditions. The current version of the app was developed to measure symptoms of schizophrenia like low mood and difficulty thinking, says Isaac Galatzer-Levy at AI Cure. Conventionally, these have been harder to measure than symptoms like hallucinations and delusions, he says. To do this, the app tracks facial movements, as well as the content, tone and pitch of a person’s speech. Some people with schizophrenia move more slowly, and show less emotion on their faces, says Galatzer-Levy. It can then send a score to the person’s doctor, rating these symptoms. However, the app isn’t designed to spot all symptoms associated with the condition, such as hallucinations or delusions. The team tested the app with 21 people who have schizophrenia and nine people who don’t. The participants made weekly recordings over 12 weeks. Each person was also evaluated by a clinician at Mount Sinai Hospital in New York at the start and end of the study. The results of this trial suggest that the app’s ratings “are highly correlated” with those of a clinician, says Galatzer-Levy, who presented the work at the European College of Neuropsychopharmacology annual meeting in Copenhagen, Denmark. The app has also been trialled by pharmaceutical company Takeda, which plans to use it to assess how well schizophrenia drugs work in clinical trials. However, AICure doesn’t yet have enough data to prove its app works, says Saeed Farooq at Keele University, UK. “The sample size is very small,” he says. “We see these results as proof of concept more then as a complete diagnostic model,” says Galatzer-Levy. “We are working to capture more data,”
9-23-19 Hypersexual disorder linked to genes that regulate love hormone
Hypersexual disorder may stem from a problem in the way individuals regulate the hormone oxytocin. The discovery could open the door to new treatments. People with hypersexual disorder have behaviour associated with intense sexual fantasies to the extent that it can be distressing and disruptive to their life. However, it is contentious whether it should be considered a clinical condition. Little is known about the biological underpinnings of hypersexual disorder. To find out more, Adrian Boström at Uppsala University in Sweden and his colleagues studied whether people with the condition have different gene expressions. They compared blood samples from 60 people with hypersexual disorder and 33 people without the condition to see if they had different epigenetic markers – patterns in their DNA that affect which genes are switched on and off. The results identified two regions of DNA that were different in people with the condition. These differences were associated with reduced levels of a molecule called MIR4456, which suppresses signalling of oxytocin, sometimes called the “love hormone” due its role in human bonding. This was consistent with further work showing that people with hypersexual disorder had unusually high oxytocin levels, which dropped after they underwent cognitive behavioural therapy. The findings suggest that using drugs to regulate the hormone could be a way to regulate the condition.
9-23-19 UK families in buyers club fly to Argentina for cystic fibrosis drugs
Six British people have travelled to Argentina to get supplies of two potentially life-saving medicines for cystic fibrosis that are unavailable at home because the National Health Service in England says they are too expensive. Five need a medicine called Orkambi, the branded version of which has an official price of about £100,000 per year. There is no valid patent on the treatment in Argentina, however, so a company there sells a generic version for £24,000. The sixth person bought a similar treatment. Orkambi, which consists of two drugs combined, was approved three years ago. Studies on its effectiveness have given mixed results, but one of the most favourable finds it nearly halves the rate of disease progression. But price talks between manufacturer Vertex and NHS England are in deadlock. So people with cystic fibrosis and their families have set up a “buyers club” to source the cheaper version. The families flew to Argentina last week to get a three-month or six-month course of the treatments. They had to have consultations by Skype with an Australian doctor who was the only medic willing to write prescriptions for this unusual set-up. However, their NHS doctors have agreed to monitor the patients during treatment, to check for side-effects. “It’s a promising start but what’s vital is that we get access for everyone,” says Rob Long, who helps run the buyers club and was one of those who made the recent trip. Long says the UK should take other steps to provide the medicine. For instance, the NHS could begin a clinical trial, which could legally use the generic medicine. Some families of people with cystic fibrosis are considering moving to Scotland, which has recently agreed to provide Orkambi through the NHS, despite the Scottish Medicines Consortium saying the price was too high.
9-22-19 When two people fancy each other their heart rates jump in harmony
If you want someone to like you, forget about body language – the real measure of whether two people hit it off is how much they synchronise internal bodily functions, like heart rate and sweating. People on a mock blind date liked each other more if they had simultaneous surges in their heart rate and skin conductivity. “You hear about people who are well suited to each other in theory but there is no spark – we wanted to know if you can quantify the spark,” Mariska Kret of Leiden University in The Netherlands said at the European Federation of Primatology meeting in Oxford last week. Kret’s team investigated by setting up a cabin at a music festival, where people could take part in short one-to-one meetings with potential partners. They were allowed to just look at the other person for two minutes and also given an additional two minutes for chatting. All the 140 people who took part were straight, as only a few gay people volunteered and their visits to the cabin didn’t coincide with each other’s. Subjects were hooked up to sensors that measured their heart rate and skin conductivity and wore eye-gaze-tracking glasses, and all their body movements were recorded. At the end, they answered questions about the meeting, including whether they would like a real date, and whether they thought their partner would. The researchers found there was no body language that predicted whether or not people liked their partner – including eye gaze, facial expressions, face touching and nodding. Sometimes people did “mirror” each other’s behaviour – such as smiling or nodding when the other person did – but contrary to popular belief, there was no correlation between mirroring and whether there was any spark of attraction. The researchers have posted their findings to a preprint server ahead of formal peer review.
9-21-19 DR Congo to introduce second Ebola vaccine
Authorities in the Democratic Republic of Congo are planning to use a second Ebola vaccine to help control an outbreak that has killed more than 2,100 people. In July, former Health Minister Oly Ilunga opposed its use saying it had not been proved effective. But DR Congo health officials say the vaccine, developed by Johnson & Johnson, is safe. This outbreak, in the east of DR Congo, is the second largest on record. The largest was the epidemic that ravaged parts of West Africa from 2014 to 2016, killing more than 11,000 people. The Johnson & Johnson vaccine will complement the vaccine manufactured by Merck which has been administered to 225,000 people in the past year, according to a government statement. But DR Congo's Ebola response team have not yet said when it will be introduced. Addressing concerns over safety, the team said, in a statement quoted by Reuters, that "it is a vaccine that other countries already use. Why can't we use it... to protect our population?" Leading health experts have said that the second vaccine is safe and could be an important tool in holding back the spread of the virus. Earlier this year, Johnson & Johnson said it had 1.5 million doses available to be deployed. The current vaccine, which is in short supply, is only being given to health workers and people who might have been exposed to the virus. The new vaccine could create a protective wall, vaccinating people outside the immediate outbreak zone. The Congolese authorities intend to use the second vaccine outside the infected areas in Ituri and North Kivu provinces. They first want to protect the small Congolese traders who regularly cross into Rwanda. There have been concerns that the new vaccine - which requires two injections at least 25 days apart - may be difficult to administer in a region where the population is highly mobile, and insecurity is rife. The Merck vaccine requires just one injection.
9-21-19 Australia has a huge shortage of the medical isotope needed for scans
Australia is facing possibly its worst ever shortage of medical isotopes, meaning 10,000 people or more may miss out on vital diagnostic scans. The isotope molybdenum-99 is crucial to the diagnosis of conditions such as cancer, heart disease, neurological disease, and skeletal, renal and digestive disorders. Uranium fission produces the isotope, which then decays into the commonly used imaging agent technetium-99m. But now, a problem at Australia’s only nuclear reactor has stopped the extraction of molybdenum-99 after it is produced. The reactor itself is unaffected, but a valve fault in the facility that extracts the medical isotope is to blame. As a result, the medical community only has around 31 per cent of its normal supply of the medical isotopes this week, and as many as 10,000 people may be missing out on vital scans, says nuclear medicine advisor Geoff Currie, at Charles Sturt University, Australia. Supply is set to drop even lower next week as the last of Australia’s domestic supplies run out, he says. Supplies of molybdenum-99 are precarious due to its relatively short half-life of 67 hours, meaning the isotope decays too quickly to be stored for a long period of time. Once inside the body, technetium-99m emits gamma rays that are detectable, making it easy to create images of muscles, bones and other areas of interest. Without it, imaging for everything from suspected bone fractures to pre-surgery scans are being delayed.For example, a patient diagnosed with breast cancer may be unable to have the scans necessary to show their surgeon which lymph nodes to closely examine to evaluate cancer spread, delaying the surgery by days or more, says Currie.
9-20-19 Herpes vaccine to be tested in humans after best result yet in animals
Hopes have been raised that we will soon have a vaccine to halt the spread of genital herpes, following an animal study that has achieved better results than any previous trial. More than 1 in 10 people worldwide are infected by the virus. The herpes simplex 2 virus (HSV2) is spread by vaginal, anal or oral sex. People remain infected for life, as some of the HSV2 viruses hide away in nerve cells where they lie dormant. Most people never realise they are infected but others suffer from outbreaks of painful symptoms, including genital lesions. The virus can also cause complications such as meningitis, and is occasionally passed on to babies during birth with fatal results. People are most infectious when they have genital lesions but even those with no symptoms often still shed the virus and can infect others. So far efforts to develop a vaccine have failed. But an experimental vaccine developed by Harvey Friedman at the University of Pennsylvania has prevented genital lesions in all mice and guinea pigs tested. In 98 per cent of mice and 80 per cent of guinea pigs it also prevented the low-level “hidden” infections. Other experimental vaccines regarded as promising enough to test in humans have failed to prevent these hidden infections in animals. “Our results in mice and guinea pigs are very encouraging – better than anything we have seen in the literature,” say Friedman. “But we won’t know if this vaccine will work until it is tested in humans.” Many vaccines consist of modified or inactivated viruses. Friedman’s vaccine is unusual in that it consists of messenger RNA (mRNA) molecules that code for three HSV2 proteins. When these mRNAs get inside cells in the body, the cells produce the viral proteins, triggering an immune response. No mRNA-based vaccine has yet been approved, but some are already in human trials.
9-20-19 Vape ban: Good news for tobacco?
President Trump’s proposal to ban flavored e-cigarettes may drive many Americans back to cigarettes, said Christopher Palmeri and Jeff Green in the Los Angeles Times. Responding to an outbreak of hundreds of serious lung illnesses from bootleg vapes that killed a seventh person this week, Trump said the Food and Drug Administration will outlaw everything but tobacco-flavored vapes, as Michigan and New York state recently did. Flavors like buttered popcorn and mango helped create “an explosion” in teen vaping, and Trump said concern for his 13-year-old son, Barron, helped make up his mind. But hundreds of thousands of teens already addicted to nicotine—and 9 million adults who vape—may simply replace vaping with tobacco products. By banning flavored vapes, said Amanda Mull in TheAtlantic.com, Trump may be “closing the barn door after the horse has gotten out.” Nobody vapes “because the flavor is so awesome,” said David Marcus in TheFederalist?.com. That’s why Trump’s ban is so clueless. “If kids want to taste bubble gum, they can buy, you know, bubble gum.” Vaping giants like Juul need to be upfront about the fact that they’re in the nicotine business, and police themselves accordingly. They should spend billions ensuring that retailers don’t sell to minors, while rightfully touting the “scientific consensus” that e-cigarettes are safer than smoking. The combustion involved in smoking cigarettes creates tar and a host of carcinogenic chemicals not present in e-cigarettes’ watery vapor. True, but nicotine is also a dangerous and addictive drug, said David von Drehle in The Washington Post, and vaping fluid itself contains chemicals that damage blood vessels. “The idea of safe smoking” is “a lie,” and the vaping industry’s fruit- and candy-flavored pods “are proof of evil intent.” “The massive surge in teen vapers” is a legitimate concern, said Robert Gebelhoff in WashingtonPost.com. But the evidence suggests that the lung illnesses that led Trump to act were caused by black-market cartridges of marijuana oil cut with dangerous vitamin E acetate. Banning flavored vapes will only drive more nicotine addicts and teens to the black market, which will be happy to provide fruity pods. Instead of banning flavors, the government “should empower the FDA to fully regulate the industry.” That would let science, “not hysteria, guide our policy.”
9-20-19 Pharma: Purdue bankrupt in deal for opioid claims
Purdue Pharma filed for bankruptcy this week as part of a deal to end lawsuits brought by 24 states, said Steven Church and Jeremy Hill in Bloomberg.com, while other states still plan to pursue cases against the maker of OxyContin for its role in the opioid epidemic. Purdue “has little debt—the typical bankruptcy culprit—and more than $1 billion in cash, but has been so overwhelmed by lawsuits that it was forced to seek court protection.” New York state, which is not part of the settlement, has charged that in seeking to shield their money, Purdue’s owners, the Sacklers, had made about $1 billion in wire transfers “among themselves and their shell companies.”
9-20-19 Vitamin D and weakened bones
Taking high doses of vitamin D does not appear to increase bone density—and may even reduce it. The body needs vitamin D to help absorb calcium and build strong, healthy bones. So in areas with limited sunlight in winter months, such as Alaska and Canada, public health officials often encourage residents to take vitamin D supplements every day. For this new study, researchers at the University of Calgary carried out a three-year trial involving 311 healthy adults. A third of the group received 400 international units (IUs) of vitamin D each day, the second third took 4,000, and the final third got 10,000. (Canadian authorities recommend people under 70 take around 600 IUs a day.) Participants’ bone mineral density was measured at the beginning and end of the trial with CT scans. Contrary to researchers’ expectations, higher vitamin D intake correlated with declines in bone mineral density: 1.2 percent in the 400-dose group, 2.4 percent in the 4,000 group, and 3.5 percent in the 10,000 group. “Large doses of vitamin D don’t come with a benefit to the skeleton,” co-author Emma Billington tells ScienceDaily.com. “Doses of 4,000 IU or higher are not recommended for the majority of individuals.”
9-20-19 Nap for heart health
Good news for nap lovers: Catching some daytime shut-eye a couple of times a week may lower your risk of heart attack and stroke. That’s the finding of researchers from the University Hospital of Lausanne in Switzerland, who tracked 3,462 healthy adults, ages 35 to 75, for five years. They noted that participants who dozed for five minutes to an hour once or twice a week were 48 percent less likely to suffer a heart attack, stroke, or heart failure than those who never snooze in the daytime. Napping longer or more often didn’t deliver any additional health benefits. The study was only observational and so couldn’t prove cause and effect, and the researchers say it’s still unclear exactly how napping might influence heart health. “Our best guess,” lead author Nadine Häusler tells NBCNews.com, “is that a daytime nap just releases stress from insufficient sleep.”
9-20-19 The end of dental fillings?
Scientists say they have invented a special gel that will allow dentists to repair decaying teeth without the need for fillings, reports TheGuardian.com. The enamel that coats our teeth is the hardest tissue in the human body, but this complex material can’t repair itself when damaged. Dentists use many different materials to fill cavities—including resin, metal alloys, amalgam, and ceramics—but none sticks perfectly to enamel and so they often come loose. To crack this problem, researchers in China used a gel containing calcium and phosphate—enamel’s building blocks—to encourage teeth to self-repair. In trials, the gel was applied to human teeth that were then placed in a fluid that mimics conditions inside the mouth. Within 48 hours, the gel had created a 2.7-micrometer layer of a substance matching the structure, strength, and wear-resistance of natural enamel. While that’s only a tiny fraction of the depth needed to tackle cavities, the process could be repeated to build up the repair layer. “After intensive discussion with dentists,” says co-author Zhaoming Liu, from Zhejiang University, “we believe this new method can be widely used in future.”
9-20-19 Mystery of why humans walk upright may be explained by surprise fossil
We might have misunderstood one of the greatest mysteries of human evolution. For decades, its been unclear why we began walking on two legs instead of moving on all fours as it is assumed our great ape ancestors did. But new evidence suggests the first great apes may have moved on two legs a little like we do. This means the real mystery is not why we walk on two legs, but why we stuck with this walking style while the other living great apes dropped down to all fours. Humans are one of four major forms of great ape today. Animals in the other three groups – the chimps and bonobos, the gorillas, and the orangutans – typically use all four limbs when they move around on the ground. Researchers have always thought that walking on all fours is the primitive condition, and hominins were the only great apes that evolved to walk on two legs. But Carol Ward at the University of Missouri says Earth has been home to dozens of great ape species over the past 20 million years, and the more we learn about them, the more it seems that today’s four-legged great apes are the unusual ones. “The modern great apes – like chimpanzees – are real oddballs,” she says. The latest evidence comes from an early great ape called Rudapithecus that lived in what is now Hungary about 10 million years ago. Ward and her colleagues, including David Begun at the University of Toronto, have spent several years carefully examining a Rudapithecus pelvis that Begun unearthed in 2006. Their analysis shows that it was surprisingly like ours in one important respect: the distance between the hip sockets and the point the pelvis contacts the base of the spine was relatively short. Ward says this implies that Rudapithecus had a long flexible lower back like ours. Because of the way our spine flexes below the rib cage, we can curve our lower back and bring the weight of our torso over our hips for easy upright walking. Ward suspects Rudapithecus could do this too to some degree, implying it could walk on two legs.
9-20-19 The day that doomed the dinosaurs
Using rock samples extracted from deep beneath the Gulf of Mexico, scientists have created a detailed sequence of events of the most calamitous day for life on Earth, when a 6-mile-wide asteroid smashed into the planet 66 million years ago and brought an end to the age of dinosaurs. The geologic account was unearthed by an international team that used a drilling rig to tap into the heart of the asteroid’s crash site—the 125-mile-wide Chicxulub crater off Mexico’s Yucatán Peninsula. The extracted cores show that hundreds of feet of sediment built up rapidly after the impact, reports The Wall Street Journal. “We have [430 feet] in a single day,” says study co-leader Sean Gulick, from the University of Texas at Austin. “We can read it on the scale of minutes and hours.” The strike itself blasted a cavity in the ocean floor some 20 to 30 miles deep and sent a colossal plume of lava into the air, creating a peak higher than Mount Everest. It collapsed within minutes, pushing out huge waves of lava that solidified into a ring of peaks. Seawater began washing over these peaks some 20 minutes later, blanketing them in impact rocks and shards of volcanic glass. Finally, backwash from the mega-tsunamis triggered by the impact added more finely graded debris. That included charcoal, evidence of great fires sparked on nearby landmasses by the heat of the asteroid strike. The sediments suggest the blast also blew hundreds of billions of tons of sulfur from crushed ocean rock into the atmosphere, blocking off the sun and causing a global winter that would kill off 75 percent of life on Earth. Further analysis of the rocks, Gulick says, will yield more insights. “The discoveries keep coming.”
9-20-19 Why tumbleweeds may be more science fiction than Old West
Salsola plants form tangled balls of dead foliage to spread their seeds. Spotting a tumbleweed doesn’t necessarily mean you’re anywhere near the O.K. Corral. Those dried-up, gray and brown tangles of Salsola plants have blown through many a Western movie, but they aren’t all that Western. You can find the common S. tragus in Maine, Louisiana, Hawaii and at least 42 other states. What’s more, S. tragus isn’t even native to North America, says evolutionary ecologist Shana Welles of Chapman University in Orange, Calif. When the plant arrived on the continent over a century ago, it wasn’t welcome. An 1895 agricultural bulletin blames the accidental arrival on “impure” flax seed brought from Russia to South Dakota during the 1870s. From there, the adaptable S. tragus rode the rails, surviving a range of climates and really thriving in places like California’s Central Valley. Welles, who is 5’8”, says, “I definitely have stood next to ones that were taller than me.” The plants are more famous dead than alive. Even Welles, who did her Ph.D. on tumbleweeds, says, “the flowers look like almost nothing.” The lentil-sized fruits, however, have a certain botany-geek charm. Each one grows papery, sometimes pinkish flares of tissue called fruit wings. A single S. tragus plant can create more than 100,000 of those fruits, which are crucial to understanding the big hairball-like tangles. When fruits and seeds form, the plant grows a “break here” tissue layer that weakens the stalk at the base. Wind eventually snaps off the whole branching architecture to blow where it will. “There is no living tissue of the mother plant when it’s tumbling,” Welles says. A tumbleweed is just a maternal corpse giving her living seeds a chance at a good life somewhere new.
9-19-19 1 in 4 U.S. high school seniors has vaped recently — up 4.5 percent from 2018
E-cig use continues to rise among high school and middle school students in 2019. The crowd of teens and tweens vaping in their school bathrooms and just about every place else is getting bigger. One out of every 4 high school seniors in the United States reported recent vaping, according to an annual behavioral survey called Monitoring the Future. Among sophomores, that ratio was 1 in 5, and for 8th-graders it was 1 in 11. Those results mark a 4.5 percent rise in recent vaping within the past 30 days by 12th-graders over the previous year, a 4.1 percent rise among 10th-graders and a 2.8 percent increase for 8th-graders from 2018, researchers report online September 18 in the New England Journal of Medicine. “Unfortunately, I am not at all surprised by these increases in use by adolescents,” says Susanne Tanski, a primary care pediatrician at the Dartmouth Geisel School of Medicine in Hanover, N.H. “Use among teens and young adults is incredibly common, frequent and leading to addiction.”To quantify how many teens may be addicted, the survey asked for the first time about daily nicotine vaping, defined as having used e-cigarettes on at least 20 of the previous 30 days. Nearly 12 percent of 12th-graders, 7 percent of 10th-graders and 2 percent of 8th-graders reported a daily vaping habit, which suggests nicotine addiction, the study authors say. Nicotine can harm adolescent brain development, which can impact learning, attention and impulse control (SN: 12/19/18). “We are seeing young people who are struggling with nicotine addiction that is more intense than we saw with regular cigarettes,” Tanski says. The growth in teen vaping also comes as health officials cope with an outbreak of severe vaping-related illnesses and deaths across the United States (SN: 9/6/19). Officials don’t yet know what substance or product is fueling the lung injuries.
9-19-19 Man sees the world in miniature after a stroke damages his brain
A man whose brain was damaged by a stroke now sees all objects and people about a third smaller than their actual size. The 66-year-old had a stroke in December 2017 that cut off oxygen to the back right of his brain. Afterwards, he noticed that everything appeared strangely smaller than normal. For example, at a clothing shop, he mistakenly picked up an extra-large T-shirt thinking it was his usual medium size. Doorways suddenly looked too small to fit through, and he thought his wife must have washed their curtains in hot water because they looked like they had shrunk. By comparing familiar objects and people with his memory of their actual sizes, he realised they now all appeared about 30 per cent smaller. To try to understand what was going on, Nils van den Berg at the University of Amsterdam in the Netherlands and his colleagues devised a series of tests for the man, who they refer to as DN. In one test, DN had to visually estimate the size of 10 different cubes on a table in front of him. Consistent with his subjective experience, he estimated each cube to be about 30 per cent smaller than 11 other people did. This distorted size perception seemed to be related to problems with DN’s left visual field. For example, when he looked at two cubes sitting next to each other, he thought the left cube was smaller than the right one, even when it was the same size or bigger. Computer tests showed that he also had difficulties identifying the shape, location and motion of objects in his left visual field. This makes sense, since information from the left visual field is usually processed by the back right of the brain, which is where DN’s stroke damage occurred, says van den Berg.
9-19-19 A hat that zaps the scalp with electricity helps reverse male balding
An electric patch makes hairless mice grow fur and may reverse balding in men when fitted inside a specially designed baseball cap. At the moment, men who don’t want to go bald can treat hair loss using minoxidil lotion, finasteride pills or hair transplant surgery. But minoxidil doesn’t work for everyone, finasteride can reduce sex drive and fertility, and surgery is painful and expensive. Stimulating the scalp with electric pulses has also been shown to restore hair growth. However, it isn’t a very practical treatment because it involves being hooked up to a machine or battery pack for several hours a day. To overcome this hurdle, Xudong Wang at the University of Wisconsin-Madison and his colleagues have developed a wireless patch that sticks to the scalp and generates electric pulses by harnessing energy from random body movements. The 1-millimetre-thick plastic patch contains layers of differently-charged materials that produce electricity when they come into contact and separate again – a phenomenon known as the triboelectric effect. When the flexible patch was attached to the backs of rats, their movements caused it to bend and stretch, activating the triboelectric effect. The resulting electric pulses stimulated faster hair re-growth in shaved rats compared with minoxidil lotion and inert saline solution. Next, Wang’s team tested the patch on mice that were hairless because of a genetic deficiency in hair growth factors. After nine days, 2-millimetre-long fur grew on their skin under the patch, whereas only 1-millimetre-long hair grew on adjacent skin areas treated with minoxidil and saline solution. Hair density was also three times greater for the patch-treated areas than those treated with minoxidil and saline.
9-19-19 Alcohol-producing bacteria could cause liver disease in some people
A majority of patients with the condition had microbes churning out ethanol, researchers find. Friendly gut bacteria that make their own alcohol may seem like the life of the party. But they could be dangerous friends to have. These ethanol-producing microbes may cause nonalcoholic fatty liver disease, researchers report September 19 in Cell Metabolism. Fatty liver disease results when too much fat is stored in the liver, and can lead to severe inflammation, liver damage and cancer. The disease, which affects about a quarter of people in the United States, is associated with obesity, type 2 diabetes and high cholesterol. Heavy alcohol drinking can lead to fatty liver disease, but it’s been less clear why nondrinkers or people who drink moderately develop the condition. Previous studies have implicated gut microbes in the disease. So Jing Yuan of the Capital Institute of Pediatrics and the Chinese Center for Disease Control and Prevention in Beijing and colleagues examined bacteria from the feces of 48 healthy people and 43 with nonalcoholic fatty liver disease, including 32 who suffered from a severe form of the disease called nonalcoholic steatohepatitis, or NASH. Both groups had similar levels of gut bacteria called Klebsiella pneumoniae in their stools. But in 61 percent of people with nonalcoholic fatty liver disease, the bacteria churned out high and medium levels of alcohol. Only 6.25 percent of healthy people carried the mid- to high-alcohol-producing bacteria. When the researchers transplanted gut bacteria including alcohol-churning K. pneumoniae from a person with NASH into mice, the rodents also developed fatty livers and inflammation. But selectively killing the alcohol-producing bacteria before the transplant resulted in no liver problems.
9-19-19 Denisovans: Face of long-lost human relative unveiled
Researchers have provided the first glimpse of what an ancient group of humans looked like. Denisovan remains were discovered in 2008 and human evolution experts have become fascinated with the group that went extinct around 50,000 years ago. One of the biggest questions had been over their appearance, with no full sketches of the Denisovan drawn up. But now a team of researchers have produced reconstructions of our long-lost relatives. Who were the Denisovans? Around 100,000 years ago there were several different groups of humans including modern humans, Neanderthals and Denisovans. "In many ways, Denisovans resembled Neanderthals but in some traits they resembled us and in others they were unique," said Prof Liran Carmel, a researcher at the Hebrew University of Jerusalem. Denisovans are thought to have been based in Siberia and eastern Asia. Scientists have found evidence that the Denisovans lived at high altitudes in Tibet, passing on a gene that helps modern people cope at similar elevations. It is not yet known why they disappeared. They only came to the attention of the world after archaeologists investigated remains in a cave in Siberia little over a decade ago. So far, the only Denisovan remains discovered are three teeth, a pinky bone and a lower jaw. Up to 6% of present-day Melanesians and Aboriginal Australians contain Denisovan DNA, according to researchers. The reconstructions - based on complex DNA analysis of Denisovans, Neanderthals, Chimpanzees and humans - show that the Denisovan skull was probably wider than that of us or Neanderthals. They also appeared to have no chin. The experts predict many Denisovan traits that are similar to that of Neanderthals including a sloping forehead, long face and large pelvis, and others that are unique among humans, like a large dental arch.
9-19-19 Ancient DNA reveals the first glimpse of what a Denisovan may have looked like
Only a few fossils of the enigmatic hominids have been found Scientists have painted a portrait of a young female who belonged to a mysterious, humanlike population known as Denisovans around 50,000 years ago. Here’s the kicker: Only a handful of Denisovan fossils have been found, including the youngster’s pinky finger. So a team led by evolutionary geneticists David Gokhman and Liran Carmel of the Hebrew University of Jerusalem reconstructed the Denisovan teen’s skeleton using only a palette of ancient DNA patterns. A description of how the researchers transformed DNA into a physical appearance appears September 19 in Cell. “This is the first reconstruction of the skeletal anatomy of Denisovans,” Carmel says. A drawing based on that skeleton shows the Denisovan gazing ahead coolly with wide, dark eyes framing the bridge of a broad nose. That profile, and the rest of the girl’s appearance, was gleaned from key changes to parts of her DNA that regulate the activity of genes involved in skeletal development, the team says. Scientific reactions to the Denisovan girl’s genetically informed appearance range from cautious curiosity to outright skepticism. This is “a pioneering piece of research, which at first glance seems almost like science fiction,” says paleoanthropologist Chris Stringer of the Natural History Museum in London. A final verdict on the accuracy of the ancient girl’s portrait awaits discoveries of more Denisovan skeletal parts, he adds. Denisovans have posed an evolutionary enigma since the Siberian discovery of part of the ancient girl’s little finger in 2008 (SN: 8/30/12). Only a few other Denisovan fossils have been found — several teeth, a limb bone and a lower jaw (SN: 5/1/19). Ancient DNA analyses indicate that Denisovans, who inhabited parts of Asia from around 300,000 to 50,000 years ago, were more closely related to Neandertals than to Homo sapiens. Some present-day human populations carry small amounts of Denisovan ancestry.
9-19-19 This is almost certainly not what Denisovans looked like
Until recently, the only evidence for the existence of a mysterious group of ancient humans known as the Denisovans was ancient DNA extracted from a fingerbone and three teeth found in the Altai mountains in Siberia. Now a team has created the above portrait of a young Denisovan woman based on that fingerbone DNA – but other researchers are sceptical of the method they used. Like Neanderthals, Denisovans are an extinct type of human that interbred with Homo sapiens. Some people in Asia and Australasia today carry remnants of Denisovan DNA in their genomes, but we still know very little about our ancient cousins. Liran Carmel at the Hebrew University of Jerusalem and his colleagues have used Denisovan DNA to generate a portrait that roughly represents what Denisovans looked like. “Our reconstruction is generalistic,” says Carmel. “We just reconstruct the face of the human group, not of a specific individual.” There’s long been interest in working out what people look like based on their DNA alone, for instance to help identify suspects from a crime scene. But our appearance depends on thousands of variants in gene sequences, each of which usually has only a tiny effect. “Today we cannot predict very much about a person’s bone morphology,” says John Hawks of the University of Wisconsin-Madison. But instead of looking at the DNA sequence of genes to predict appearance, Carmel and his colleagues have looked at how active these genes were. When genes get switched off in cells, epigenetic tags called methyl groups are added to their DNA. The team has developed a way to identify where these tags have been added to ancient DNA. The team compared the methylation patterns in the ancient fingerbone to those in bone cells from modern humans and chimpanzees, revealing thousands of genes whose activity was likely different in Denisovans. Next, the team tried to identify which of those changes would affect bone shape, based on what happens when mutations disable these genes in modern humans.
9-18-19 True nature of consciousness: Solving the biggest mystery of your mind
Far from being a mystical “ghost in the machine”, consciousness evolved as a practical mental tool and we could engineer it in a robot using these simple guidelines. CONSCIOUSNESS is a slippery concept. It isn’t just the stuff in your head. It is the subjective experience of some of that stuff. When you stub your toe, your brain doesn’t merely process information and trigger a reaction: you have a feeling of pain. When you are happy, you experience joy. The ethereal nature of experience is the mystery at the heart of consciousness. How does the brain, a physical object, generate a non-physical essence? This experience-ness explains why pinning down consciousness has been described as “the hard problem”. Subjective experience doesn’t exist in any physical dimension. You can’t push it and measure a reaction force, scratch it and measure its hardness or put it on a scale and measure its weight. Philosophers have described it as the “ghost in the machine”. Even scientific ideas about consciousness often have an aura of the metaphysical. Many scientists describe it as an illusion, while others see it as so fundamental that it doesn’t have an explanation. Always at the centre of the riddle lies its non-physicality. But what if consciousness isn’t so mystical after all? Perhaps we have just been asking the wrong question. Instead of trying to grapple with the hard problem, my colleagues and I at Princeton University take a more down-to-earth approach. My background lies in the neuroscience of movement control, what you could call the robotics of the brain. Drawing on that, I suggest that consciousness can be understood best from an engineering perspective. Far from being some sort of magical property, it is a tool of extraordinary power. It is a tool that can be engineered into machines. Our new approach shows how.
9-18-19 The 4 ingredients to create consciousness could explain our own minds
Despite decades of effort, we have been unable to understand how our brains create consciousness. An engineering approach could bring a breakthrough. WHAT is it like to be a bat? Philosopher Thomas Nagel’s 1974 question has evolved to dominate our thinking on consciousness. Nagel’s point, simply put, is that even if we could fly, and navigate using sonar, we would never grasp what it feels like to be a bat. The argument has become the “hard problem” of consciousness, the intractability of explaining subjective experience. Consciousness isn’t something you can measure or weigh; its ethereal quality is so fascinating as to verge on the mystical. Certainly it attracts plenty of mystical explanations. So it is unsurprising that, despite decades of thought, we have been unable to explain how our brains create the conscious experience. Even if we might insist that the hard problem is illusory, or that consciousness is simply the way information feels when processed in certain ways, we still need to understand how the illusion arises, and what kind of information in the brain gives rise to the feeling. Philosophy alone isn’t enough. This is where engineering comes in. To build something, you have to understand it precisely. Can we make a machine that does what a conscious being does, that constructs a self-image and uses it to produce descriptions of the world? This week, we report on just such a project (see“Creating human-like consciousness requires just four key ingredients”). The idea is that, just as any control device needs a model of the thing it is controlling, a brain needs a model of itself. The experience of a phantom limb – the feeling that an amputated arm, for example, is still present – comes about because the brain originally created an internal model of the arm to help control its movement. When the physical arm is gone, the model, the phantom, remains. The feeling of consciousness could be the phantom of the brain’s model of its own workings.
9-18-19 Giving birth two million years ago was 'relatively easy'
Human childbirth can be a long, painful, drawn-out process, needing assistance and sometimes taking days. So why do close living relatives like chimps have an easier labour, giving birth in hours and on their own? In an attempt to answer this evolutionary question, scientists have been looking at how ancient members of the human family tree gave birth. Human-like relatives two million years ago had it "pretty easy", according to birth reconstruction in a fossil. For Australopithecus sediba, which lived 1.95 million years ago in South Africa, we see "a relatively easy birth process", says study researcher Dr Natalie Laudicina. "The foetal head and shoulder breadth have ample space to pass through even the tightest dimensions of the maternal birth canal," she says. It's a different story today, where the size and shape of the modern pelvis (a trade-off needed for walking upright), and the large size of a baby's head, make for a tight fit. Human infants have to make several rotations through the birth canal during labour, rather than popping straight out. By studying the few female pelvises we have of our ancient human-like relatives - only six spanning more than three million years of evolution - researchers can get an idea of what birth might have been like further back in the human family tree. It's not the case, though, that birth became progressively more difficult during the course of human evolution. As the University of Boston anthropologist explains, the fossil "Lucy" (Australopithecus afarensis) had a more difficult birth process than A. sediba, in terms of a tighter fit between the foetus and the birth canal, but lived about a million years earlier. "There is a tendency to think about the evolution of human birth as a transition from an 'easy', ape-like birth to a 'difficult', modern birth," says Dr Laudicina, who reports the team's findings in the journal, Plos One. "Instead, what we are seeing is that is not the case."
9-18-19 C-section babies have a different microbiome - but not for long
Babies born by caesarean section have different gut bacteria to those born vaginally – but the differences largely disappear by the time the babies are between 6 and 9 months old. That’s according to the largest study into the effects of birth mode on the microbiome. Previous research has suggested that babies born by C-section are more likely to collect hospital-acquired bacteria when they are born, while those born vaginally collect microbes from their mother. Because the gut microbiome is thought to be intricately linked to health, these differences have been suggested to make C-section babies more likely to develop obesity, asthma and eczema. “The hypothesis is that the moment of birth might be a sort of thermostatic moment for the immune system… that sets the immune system for future life,” says Nigel Field at University College London. To investigate the phenomenon, Field and his colleagues collected faecal samples from 596 babies born in UK hospitals. The samples were collected by the babies’ parents over the first few weeks of life, and when the babies were between 6 and 9 months old. “We did quite a bit of experimenting to show that baby poo is pretty stable in the post for a couple of days,” says co-author Peter Brocklehurst at the University of Birmingham, UK. The team found that about 80 per cent of C-section-born babies had hospital-acquired bacteria in their guts when they were born, compared with 50 per cent of vaginally born babies. And the bacteria made up around 30 per cent of the total bacteria in C-section babies, compared with just 10 per cent in babies born vaginally. But by the time the babies were weaned at the age of around 6 to 9 months, these differences had largely disappeared. And all the babies were healthy, so the researchers can’t tell if there are any implications for health. “We don’t know the long-term consequences of these findings,” says Field.
9-18-19 Air pollution can reach the placenta around a developing baby
A study of women in Belgium found black carbon particles, or soot, within the organ. Breathing in polluted air may send soot far beyond a pregnant woman’s lungs, all the way to the womb surrounding her developing baby. Samples of placenta collected after women in Belgium gave birth revealed soot, or black carbon, embedded within the tissue on the side that faces the baby, researchers report online September 17 in Nature Communications. The amount of black carbon in the placenta correlated with a woman’s air pollution exposure, estimated based on emissions of black carbon near her home. “There’s no doubt that air pollution harms a developing baby,” says Amy Kalkbrenner, an environmental epidemiologist at the University of Wisconsin–Milwaukee who was not involved in the new work. Mothers who encounter air pollution regularly may have babies born prematurely or with low birth weight (SN: 5/13/15). These developmental problems have been tied to an inflammatory response to air pollution in a mother’s body, including inflammation within the uterus. But the new study, Kalkbrenner says, suggests that “air pollution itself is getting into the developing baby.” The study looked particularly at black carbon, a pollutant emitted in the burning of fossil fuels such as gasoline, diesel and coal. Researchers in Belgium at Hasselt University in Diepenbeek and Katholieke Universiteit Leuven used femtosecond pulsed laser illumination to test the tissue for soot. The technique involves using extremely fast laser bursts — each one-quadrillionth of a second — to excite electrons within the tissue, which then emits light. Different tissues are known to generate certain colors, such as red for collagen and green for placental cells. The black carbon was distinct and released white light.
9-18-19 Creating human-like consciousness requires just four key ingredients
Far from being a mystical “ghost in the machine”, consciousness evolved as a practical mental tool and we could engineer it in a robot using these simple guidelines. CONSCIOUSNESS is a slippery concept. It isn’t just the stuff in your head. It is the subjective experience of some of that stuff. When you stub your toe, your brain doesn’t merely process information and trigger a reaction: you have a feeling of pain. When you are happy, you experience joy. The ethereal nature of experience is the mystery at the heart of consciousness. How does the brain, a physical object, generate a non-physical essence? This experience-ness explains why pinning down consciousness has been described as “the hard problem”. Subjective experience doesn’t exist in any physical dimension. You can’t push it and measure a reaction force, scratch it and measure its hardness or put it on a scale and measure its weight. Philosophers have described it as the “ghost in the machine”. Even scientific ideas about consciousness often have an aura of the metaphysical. Many scientists describe it as an illusion, while others see it as so fundamental that it doesn’t have an explanation. Always at the centre of the riddle lies its non-physicality. But what if consciousness isn’t so mystical after all? Perhaps we have just been asking the wrong question. Instead of trying to grapple with the hard problem, my colleagues and I at Princeton University take a more down-to-earth approach. My background lies in the neuroscience of movement control, what you could call the robotics of the brain. Drawing on that, I suggest that consciousness can be understood best from an engineering perspective. Far from being some sort of magical property, it is a tool of extraordinary power. It is a tool that can be engineered into machines. Our new approach shows how.
9-18-19 Whales evolved large brains in the same way that we did
The largest brains ever to have evolved belong to whales. Now we have discovered that the marine mammals gained their big brains size in the same way we did – through massive expansion of two particular brain regions, fuelled perhaps through changes in diet. Amandine Muller at the University of Cambridge and Stephen Montgomery at the University of Bristol, UK, looked at brain size data from 18 species of whale and dolphin, as well as from 124 different land animals including 43 species of primate. With few exceptions, the whales, dolphins and primates all seem to have gained large brains through dramatic growth of the same two brain regions: the cerebellum and neocortex. Both regions are important for cognitive functions such as attention, and for controlling the movement of the body. It makes sense that the cerebellum and neocortex evolve in unison, says Montgomery, because they are physically connected by many brain pathways. “It’s possible one can only change so much without being constrained by the performance of its partner, and needing the other structure to ‘catch up’,” he says. But what drove these two brain regions to expand so dramatically in whales and dolphins? Muller and Montgomery first explored whether the trigger was a change in social behaviour. In common with some primates – including our species – whales and dolphins can form complex social groups. However, the two researchers found no strong correlation between the whale and dolphin species with the most advanced social behaviour and those with a particularly large cerebellum and neocortex. But they did discover that the whale and dolphin species with a larger cerebellum and neocortex typically enjoy an unusually broad diet, in terms of the variety of foodstuffs they consume. This might suggest that broadening the diet encouraged the evolution of larger brains.
9-18-19 Radio waves from electric devices may affect the body clock of insects
Weak radio frequency fields seem to affect the body clocks of cockroaches. If the finding is confirmed, it could mean that weak radio waves – which are already known to disorient birds – are capable of affecting a wide range of animals. However, Martin Vacha of Masaryk University in the Czech Republic, who conducted the study, says he is “very cautious” about his team’s results. In normal conditions, there might not be any effect on insects, he says, and the team isn’t making any claims about possible effects on people. Other scientists are sceptical, and say the study needs to be independently confirmed. Many claims have been made about possible effects of electromagnetic fields on humans and other animals. In particular, it is been claimed that the radio waves from mobile phones could cause cancer. But radio waves are much less energetic than, say, X-rays and don’t cause the damage to DNA that leads to cancer. Nonetheless, some researchers think they could have more subtle effects on living tissue. A couple of recent studies, for instance, have suggested that static magnetic fields affect the body clock of fruit flies. Vacha and his colleagues decided to look at whether they affect cockroaches too. His team kept cockroaches in constant dim UV light, with no clues as to whether it was night or day, and measured the animals’ activity using image analysis software. From that they worked out what time their body clocks were keeping. When they exposed the animals to either static magnetic fields or weak radio frequency broadband noise, the cockroaches’ periods of activity became an hour or two longer. In other words, their body clocks were running more slowly. Vacha says the team tested frequencies much lower than those from mobile phones. But many electric devices, such as computers, produce this kind of broadband noise.
9-18-19 Frogs evolved to be more scared after mongooses came to their island
The Amami tip-nosed frog is a battle-worn survivor of an invasion of mongooses on its island home. The mongooses left their mark on the species, leaving the frogs more skittish towards potential threats. Small Indian mongooses (Herpestes auropunctatus) were introduced to Japan’s Amami Island in 1979 to control the islands’ rat and pit viper populations. A handful spread out from a single starting point, eventually multiplying to 6000 individuals and infiltrating much of the forested island. They preyed on – and dramatically reduced – populations of native wildlife like the Amami tip-nosed frog (Odorrana amamiensis). Following a 20-year eradication campaign, most of the mongooses have now been removed and the frogs have rebounded. The situation was a great opportunity to see if the invaders influenced the frogs’ evolution, says Hirotaka Komine at the Tokyo University of Agriculture and Technology. Komine and his team searched the island for frogs. When they spotted one, they would approach and record how close they could get before the amphibian hopped away. They found that in places with greater impact from the mongoose invasion, frogs bounded away from potential threats quicker than frogs from less affected areas. The results suggest that the frogs evolved a heightened wariness in the wake of the invasion and this fear has persisted even after mongoose eradication, says Komine. The mongoose density on the island has been extremely low for at least five years, and the maximum lifespan of a tip-nosed frog is three years, so the frogs that were tested have probably never seen a mongoose. This means the skittishness is probably a genetic change, not a learned behaviour. This amplified fear may influence the island’s local ecology because it could change how the frogs acquire their own prey. Komine thinks the fearfulness may fade over time, though.
9-17-19 Wild wheat genetics offer climate hope for food crops
Wild relatives of food crops, such as wheat, host an abundant array of genetic material to help the plants cope with a changing climate. In a study over 28 years showed that populations of wild wheat developed "beneficial mutations" such as a tolerance to temperature increases. Researchers say the results improve our understanding of how plants are responding to a warming world. The findings appear in the Proceedings of the National Academy of Sciences. "We get some very exciting results," explained lead author Yong-Bi Fu, a research scientist from Agriculture and Agri-Food Canada. "One of which is that we can demonstrate that over 28 years, and 28 generations, you can see the wild relative of the plant accumulate more genetic mutations, and we found that most of the population is still adaptable." Although the team did find that there were individual specimens in the study that did not survive the conditions associated with a warmer environment, there were others that were able to adapt in such a way that meant they could cope with a warmer world. The study involved 10 populations of emmer wheat in Israel. Dr Fu say that the temperature increase over the three decades amounted to up to two degrees Celsius, which is similar to the increase that the Paris Climate Agreement hopes to limit global average temperatures from rising above pre-industrial levels. "That is really exciting because it means that the population is able to get beneficial mutations," Dr Fu told BBC News. "This mutation is crucial, and we can see that we need a lot of effort to protect and conserve the crop's diversity in the wild, natural population." The team suggested that this insight helped to improve our knowledge of how plants could adapt to future climate change. Dr Fu also highlighted the work of UK scientists who, reporting in Nature Biotechnology, who were developing ways to clone disease-resistance (R) genes from wild relatives in order to engineer broad-spectrum resistance in domesticated crops. He said that a similar approach could be used to clone climate-resistant genes from the plants' wild relatives in order to make our food crops more climate resilient.
9-17-19 Sim Singhrao on the secrets of a healthy mind at New Scientist Live
News about our microbiome and how it affects our health is everywhere. At New Scientist Live next month, biologist Sim Singhrao will delve into this topic, focusing on how our lifestyles can lead to changes in the communities of microbes in our mouths and how these changes might diminish our general wellbeing and potentially lead to diseases like Alzheimer’s. Based at the University of Central Lancashire, Singhrao’s goal is to discover causative links between oral health and the development of Alzheimer’s disease. Ultimately, she is hoping to find strategies we can use to delay or prevent the disease.
9-17-19 A new book shows how not to fall for dubious statistics
‘The Art of Statistics’ shows how to think critically about numbers and data analyses. There are, as the saying goes, three kinds of lies: lies, damned lies and statistics. David Spiegelhalter is here to keep you from being duped by data. If you’re seeking a plain-language intro to statistics, or just want to get better at judging the reliability of numbers in the news, Spiegelhalter’s The Art of Statistics is a solid crash course. The book is less about learning how to use specific mathematical tools than it is about exploring the myriad ways statistics can help solve real-world problems — and why statistical claims often have to be padded with caveats. Spiegelhalter, a statistician at the University of Cambridge, keeps things lively by tying new concepts to questions. For instance, should you fret that eating bacon will increase your risk of bowel cancer? The relative risk might make you think so: People who eat a bacon sandwich every day have an 18 percent higher risk of bowel cancer than those who don’t. But looking at the absolute risk — a rise of 6 to 7 cases per 100 people — may put your mind at ease. Spiegelhalter’s narration is encouraging, and he knows where beginners are likely to get tripped up. He makes dense sections easier to parse by including frequent recaps and lots of data visualizations, and tucking equations into footnotes. The Art of Statistics is alight with his enthusiasm for how statistics can be used to glean information for court cases, city planning and a host of other sectors. But Spiegelhalter warns readers not to forget the assumptions and uncertainties inherent in any analysis, and tells many cautionary tales about the ways statistics can go astray. Patchy samples and logical missteps can lead to faulty conclusions.
9-17-19 How circling the globe has evolved in the 500 years since Magellan’s famous trip
Botanist Jeanne Baret and journalist Nellie Bly are two women who duplicated the feat. Half of a millennium ago, Portuguese explorer Ferdinand Magellan and his crew embarked on the first voyage to successfully sail around the world. On September 20, 1519, Magellan’s five-ship fleet set sail from Spain and traveled south, crossing the Atlantic to South America. There, the sailors happened upon a channel, later dubbed the Strait of Magellan, to the Pacific Ocean, and the ships continued west. The journey was anything but smooth sailing. Magellan dealt with shipwrecks, mutiny and conflicts with indigenous people. He was killed during such a conflict in the Philippines in 1521. But his crew carried on, traversing the Indian Ocean and hooking around Africa’s southern tip to sail north back to Spain. A lone ship docked in Seville in 1522. In the 500 years since Magellan, humankind has found new ways to circle the globe. The goal of many early circumnavigations was to connect the world, says Jeremy Kinney, chair of the aeronautics department at the Smithsonian Air and Space Museum in Washington, D.C. Circumnavigation is the ultimate expression of “humans’ ability to conquer nature and geographic boundaries,” he says. 1. In late 1774 or early 1775, French botanist and explorer Jeanne Baret became the first woman to circumnavigate the world (SN: 2/8/14). 2. November will mark another circumnavigation milestone: 130 years since American journalist Nellie Bly’s 1889 record-breaking journey. 3. A 1924 series of flights by the United States Army Air Service (which later became the Air Force) is largely considered the first global circumnavigation by plane. 4. Part of the Soviet Union’s Space Race victory, cosmonaut Yuri Gagarin became the first person in space and the first to orbit Earth (SN: 4/22/61). 5. In 2017, French sailor Francis Joyon and his crew set a new fastest record for sailing around the world.
9-16-19 Vikings probably hunted Iceland's walruses to extinction for ivory
Iceland was once home to a unique subspecies of walrus, but the animals had vanished by the mid-14th century, just 500 years after the arrival of Norse settlers. The discovery suggests hunters were responsible for the walrus’s disappearance, providing some of the clearest evidence so far that humans began driving marine mammals extinct earlier than generally thought. Researchers have known for years that walruses once lived on Iceland, but opinion has been divided on whether they vanished before or after humans arrived. To settle the debate, Tange Olsen and Xénia Keighley at the University of Copenhagen in Denmark carbon dated the remains of 34 walruses found in western Iceland. Three of the walruses died after the year 874 – the date permanent settlers are thought to have reached Iceland – with the youngest dating to between 1213 and 1330. In other words, Icelandic walruses survived for a few centuries after humans arrived. A walrus hunt is described in one late 12th century Icelandic saga: the walrus’s skull and tusks are said to have been sent to Canterbury in the UK to honour the archbishop, Thomas Becket, who was murdered in the city’s cathedral in 1170. The new data indicate the walrus in question could have been local to Iceland and not simply a migrant animal visiting the island from elsewhere. Partly because of such Medieval accounts of hunting, and because we know walrus ivory was a valuable commodity at the time, Olsen and Keighley suspect that the settlers were responsible for the disappearance of Iceland’s walruses. But they also considered an alternative hypothesis: the animals might have fled the island when people arrived, as has happened elsewhere in the North Atlantic. “When hunters went to Svalbard, the females and calves moved away,” says Keighley. But she says the new study suggests this isn’t what happened.
9-15-19 A network in the brain is involved in a range of mental health issues
Depression, schizophrenia and some other mental health conditions can have very different symptoms but they all seem to be connected by a set of structures in the brain. This network may help us understand the link between certain genes and psychiatric symptoms, and suggests a focus on symptoms, rather than categorising mental health conditions, may be a better way to help people. “We know for psychiatric illnesses, the categories of diagnosis are not very reliable,” says Maxime Taquet at the University of Oxford. Psychiatric conditions have been shown to overlap when it comes to which genes they are linked to, as well as symptoms. Taquet and his colleagues wanted to find out how these shared genetic factors might influence a person’s brain structure. Looking at the brains of adults with established disorders might not answer the question, says Taquet, as the disorder or any treatments might have made changes to the brain. Instead, his team turned to children aged between 3 and 18, none of whom had been diagnosed with a psychiatric condition. Any differences in brain structure among children are more likely to be explained by genes rather than the effects of an established disorder or treatment, says Taquet. Using data already collected from 678 children in the US, the team started by searching for 1877 genetic factors that have been linked to a range of conditions, including schizophrenia, panic disorder, addiction and others. Each child was given a score based on their overall genetic risk for these conditions. His team then assessed scans of the children’s brains. There were “large differences” between the brains of high-risk and low-risk children, says Taquet, and not just in one or two regions of the brain.
9-14-19 Boosting circadian rhythms can help relieve perinatal depression
Women with perinatal depression appear to have altered circadian rhythms. Using light to reset the body clock may improve symptoms. Our bodies run on internal clocks that, in concert with light, wake us up in the morning and leave us sleepy by night time. This circadian rhythm is partly regulated by a suite of genes. These control not only the sleep-wake cycle but also a host of other functions, including metabolism, hormone secretions and body temperature – all of which cycle throughout the day. Something seems to go awry in depression. People with severe depression tend to experience disruptions to their circadian rhythms. Depression can give people daytime sleepiness and night-time insomnia, and research has found higher activity of some circadian genes in people with the condition. Perinatal depression – which occurs during and after pregnancy – seems to be similar. Women tend to get less sleep when they are pregnant, particularly if they have perinatal depression. To find out if circadian genes might play a role, Massimiliano Buoli, Cecilia Maria Esposito and their colleagues at the University of Milan, Italy, looked at seven such genes in 44 women in the third trimester of pregnancy. Thirty of the women had been diagnosed with perinatal depression. By looking at whether epigenetic tags called methyl groups were attached to the genes, the researchers could tell how active these genes were. They found that three circadian genes were more active and one circadian gene was less active in the women who had been diagnosed with depression than those who didn’t have the condition. The team also found that the more methyl groups there were, the more severe a woman’s symptoms were likely to be. This suggests that the greater the difference in circadian gene activity, the more likely a woman is to experience symptoms of depression, say Buoli and Esposito, who presented the findings at the annual meeting of the European College of Neuropsychopharmacology in Copenhagen, Denmark, last week.
9-13-19 Mystery illness: An e-cig reckoning
Amysterious vaping-induced lung illness is proving that “safer than smoking cigarettes” does not mean “safe,” said Amanda Mull in TheAtlantic?.com. Six people have died since August from this lung syndrome, which has severely sickened more than 475 Americans in recent months. Almost all patients have required hospitalization for severe shortness of breath, lung inflammation, fever, dizziness, and vomiting. Now federal health officials are warning people to avoid e-cigarettes, while scientists race to explain why “otherwise healthy” young people are falling ill. Officials say many patients were using bootleg marijuana vaporizers bought off the street, with “vape juice” diluted by vitamin E acetate, a popular skin-care oil that inflames the lungs when heated and inhaled. Some patients also used nicotine vapes, whose health risks are largely unknown despite 14 million U.S. users. Youth vaping is its own health crisis, said Julia Belluz in Vox.com. Teen usage of vapes doubled, to 21 percent, from 2017 to 2018, “the largest increase ever recorded for any substance.” With candy-like flavors such as mango and watermelon, vape giants have marketed to minors, and this week the Food and Drug Administration said Juul unlawfully advertised its products as safer alternatives to cigarettes. In fact, studies have linked vaping to wheezing, and nicotine is known to raise blood pressure, cause arteries to narrow, and even cause seizures in large amounts. The FDA didn’t gain oversight of e-cigarettes until 2016, said USA Today in an editorial, and within that “regulatory vacuum” a “Wild West culture emerged.” The “good news” is that a federal judge recently green-lighted an FDA safety review of e-cigarettes. “In the meantime, vapers beware.”
9-13-19 There is no ‘gay gene’ to predict sexuality
The largest-ever study into the link between sexuality and genetics has found that there is no “gay gene” that determines a person’s sexual orientation. Instead, same-sex attraction appears to be driven by a complex mix of genetic, cultural, and environmental influences—just like many other human traits. “It’s effectively impossible to predict an individual’s sexual behavior from their genome,” co-author Ben Neale, from the Broad Institute of MIT and Harvard, tells CBSNews.com. Homosexuality and bisexuality are a “normal part of variation in our species.” The researchers examined the genetic profiles of nearly 480,000 people in the U.K. and U.S.—about 100 times more than any previous study into genetics and same-sex attraction—who were also asked whether they had ever had a same-sex partner. The scientists identified five specific genetic variants associated with same-sex behavior, including one linked to the biological pathway for smell and others connected to the regulation of sex hormones. Overall, genetics accounts for 8 to 25 percent of same-sex behavior, when thousands of tiny variations across the whole genome are taken into account, researchers concluded. Sexual orientation “is influenced by genes but not determined by genes,” said researcher Brendan Zietsch. But genetic variation does appear to have a stronger influence on same-sex behavior in men than in women, suggesting that female sexuality is more complex.
9-13-19 Going blind from a bad diet
A teenage “fussy eater” who subsisted on junk food went blind and partially deaf because of his terrible diet, according to a new study. The unnamed British teen ate nothing but French fries, Pringles, sausages, processed ham slices, and white bread for the past decade, and first visited a doctor at age 14 complaining of “tiredness,” reports The Washington Post. He was given B12 shots and dietary advice and sent home, but by age 15 was starting to suffer from hearing and vision loss—symptoms that mystified doctors. At 17, he was declared legally blind, and doctors discovered that he still had a B12 deficiency, as well as low levels of copper, selenium, and vitamin D. The teen was diagnosed with nutritional optic neuropathy, a disorder of the optic nerve that in developed nations is caused mostly by chronic alcoholism and medications that interfere with the absorption of nutrients. It is rarely a result of poor diet, because nutritious food is readily available in the West. The case shows the importance of eating “a varied diet,” said study lead author Denize Atan, from Bristol Eye Hospital in England. “There is not a single food that will provide all the vitamins and minerals you need.”
9-13-19 HRT and breast cancer
New research has concluded that the risk of developing breast cancer from hormone replacement therapy is twice as high as previously thought, reports The Daily Telegraph (U.K.). HRT is used by millions of women around the world to relieve the symptoms of menopause, which include hot flashes and night sweats, and scientists have known of the treatment’s link to cancer since the early 2000s. To better gauge that risk, researchers analyzed data from 58 previous HRT studies, which included more than 100,000 postmenopausal women with invasive breast cancer. The metastudy revealed that the general risk of breast cancer for women ages 50 to 69 who have not taken HRT is 6.3 percent. But for women on the most common form of HRT—estrogen and daily progestogen—the risk jumps to 8.3 percent, equivalent to one extra cancer case per 50 users. The risk rises to 6.8 percent for those on estrogen-only therapy, and 7.7 percent for those taking progestogen every two or three days. The risk goes up the longer a woman is on HRT and persists even a decade after treatment stops. “We don’t want to be unduly alarming,” says co-author Richard Peto, from the University of Oxford. “But we don’t want to be unduly reassuring.”
9-13-19 Tattoo needles in lymph nodes
More than ink enters your body when you get a tattoo—metal fragments from tattoo needles that can cause allergic reactions also get left behind. In a new study, researchers examined 12 new steel tattoo needles with a high-powered microscope, both before and after use, reports The New York Times. They found that chromium and nickel particles break off during the tattooing process and become embedded in the skin. Those metals can travel through the body and build up in lymph nodes, potentially triggering an allergic reaction. Interestingly, the needle didn’t fragment when black ink alone was used; the breakdown was caused by titanium dioxide, an abrasive chemical additive used to brighten colored tattoo ink. The research builds on earlier studies that showed pigments can leach from tattoo sites and accumulate in lymph nodes. Anyone thinking of getting a tattoo, says lead author Ines Schreiver, from Germany’s Federal Institute for Risk Protection, should be aware they could be exposed to “impurities that might be allergenic or carcinogenic.”
9-13-19 An island grave site hints at far-flung ties among ancient Americans
Great Lakes and southeastern hunter-gatherers may have had direct contact 4,000 years ago. Ancient North American hunter-gatherers had direct contacts with people living halfway across the continent, researchers say. A ceremonial copper object and related burial practices at a roughly 4,000-year-old human grave site encircled by a massive ring of seashells in what’s now the southeastern United States closely correspond to those previously found at hunter-gatherer sites near the Great Lakes. Because the object and practices appear together, emissaries, traders or perhaps even religious pilgrims must have traveled most or all of the more than 1,500 kilometers from the Upper Midwest to St. Catherines Island, off Georgia’s coast, the researchers conclude September 2 in American Antiquity. Until now, “there was no clear evidence for direct, long-distance exchange among ancient hunter-gatherers in eastern North America,” says anthropologist Matthew Sanger of Binghamton University in New York. Finds at the McQueen shell ring on St. Catherines Island suggest that such exchanges involved objects and ideas that had spiritual significance, such as how to bury the dead. Only a massive, enigmatic earthworks in northern Louisiana called Poverty Point, inhabited from around 3,700 to 3,200 years ago, has yielded copper and other artifacts apparently obtained directly from groups based hundreds of kilometers or more away. But the findings at the McQueen shell ring show for the first time that such exchanges weren’t limited to great gatherings but also occurred between smaller groups going about their daily lives, says Harvard University anthropological archaeologist S. Margaret Spivey-Faulkner, who was not involved in the study.
9-13-19 Research on postmen's testicle warmth wins Ig Nobel
Research measuring if there is a difference in temperature between the left and right testicles is one of the winners of this year's spoof Nobel prizes. Fertility experts Roger Mieusset and Bourras Bengoudifa measured the temperature of French postmen's testicles, both naked and clothed. They found the left one is warmer, but only when a man has his clothes on. The Ig Nobel prizes were announced at a ceremony at Harvard University. In their research "Thermal Asymmetry of the Human Scrotum" published in the journal Human Reproduction, the researchers explained their experiment involved measuring scrotal temperatures with probes every two minutes. They asked 11 postal workers to stand for 90 minutes while they measured the temperature of their scrotums. In another experiment, they measured the temperatures of 11 bus drivers while they were sitting down. The Ig Nobels are spoof prizes that are published in the Annals of Improbable Research but many of the topics recognised in the awards actually have a serious point to them. In this case, other research has suggested the temperature around testicles can affect men's fertility. The quality of men's sperm in the Western world is in decline, but little is known about how to improve it. Craig Franklin told the BBC that he was devastated to find out he had no sperm at all.
9-13-19 We may have a basic form of sign language in common with chimpanzees
We can communicate with chimps. When put to the test, people can usually understand the meaning of ten common gestures used by chimpanzees. Human infants also use some of the same gestures before they can talk, although we don’t yet know if their meanings are the same. The gestures may be the remnants of a basic sign language used by our last common ancestors with apes, says Kirsty Graham, who did the work while at the University of St Andrews in Scotland. “This gestural communication is probably biologically inherited among the great apes – including humans.” One idea about language evolution is that we developed the ability to speak by building on a more primitive kind of sign language. To investigate, the St Andrews team have been recording the meanings of gestures used by gorillas, chimps and bonobos, a related species, to put together the online Great Ape Dictionary. So far they have found about 70 gestures, with about 16 different meanings, as several gestures can convey the same meaning. Most are shared by the three great apes. The researchers set up a website where members of the public could watch short video clips of ten common signs made by chimps and bonobos, and guess what each one meant from four options. By chance they should have got a quarter of the answers right. But people did better than that, picking the correct answer 52 per cent of the time, and this rose to 57 per cent if they were given a brief description of the situation when the gesture was used. Some gestures had success rates over 80 per cent, for instance, when a chimp strokes near its mouth, which means it is asking for food, says Graham, who presented the findings at the European Federation of Primatology meeting in Oxford this week.
9-13-19 Hans Christian Gram: The biologist who helped investigate bacteria
Biologist Hans Christian Gram devised one of the most important staining techniques used in microbiology to identify bacteria under a microscope. Hans Christian Gram, the inventor of the Gram staining technique, was a pioneering biologist who devised the system of classification which led to as many as 30,000 formally named species of bacteria being investigated. He’s the subject of the latest Google doodle, created to honour his birth date of 13 September 1853. Gram, working with German pathologist and microbiologist Carl Friedlander, devised the technique in Berlin in the early 1880s. It is still known as one of the most important staining techniques used in microbiology to identify bacteria under a microscope. Gram first dripped reagents, a substance designed to cause a chemical reaction, onto lung tissue samples. He found differences in the colouring of bacteria that is now known to be Streptococcus pneumoniae and Klebsiella pneumoniae. The differences Gram observed are a result of the composition of the bacterial cell wall. Some bacteria have a cell wall composed of peptidoglycan, a polymer of sugar and amino acids. These “gram-positive” bacterial cells retain the colour of a stain – usually a complex of crystal violet and iodine, or methylene blue – and appear purple or brown under the microscope. Others, that do not contain peptidoglycan, are not stained and are referred to as gram-negative, and appear red. Its popularity peaked between 1940 and 1960. Pierce Gardner, an associate professor of medicine at Harvard Medical School, wrote about the Gram stain and its interpretation in 1974: “It is our feeling that the Gram-stained smear should be considered part of the physical examination of the patient with an acute bacterial infection and belongs in the repertoire of all physicians delivering primary care in acutely ill patients.”
9-13-19 Early whales swam doggy paddle across the ocean from India to Africa
Some early whales may have swum using their arms as well as their legs, a bit like a dog paddling in water. Despite this primitive swimming style, they seem to have managed to spread long distances across the ocean, from India to the western tip of Africa at a minimum. “Even if they are not very good swimmers, they could cross at least one ocean,” says Quentin Vautrin at the University of Montpellier in France. Whales are descended from hoofed land animals similar to modern deer, so the first proto-whales to venture into the water presumably used all four limbs for propulsion, as four-legged animals do today. More modern whales swim by undulating their entire bodies and only use their front limbs – their flippers – for steering. This crucial evolutionary transition took place between 50 and 35 million years ago. We do not fully understand what happened to early whales’ arms during this time because we don’t have many fossils. “We only know the forelimbs for a few species,” says Vautrin. His team has now found a new one. Vautrin and his colleagues unearthed a partial skeleton of an early whale called a protocetid in Senegal. The fossil includes two vertebrae, two ribs, fragments of the feet and tail – and most of an arm. Dated at between 43 and 41 million years old, it sits in the middle of whales’ transition to marine life. “We are far from the earliest whale, but we are a few million years before the real whales,” says Vautrin. Even at this relatively late stage in the evolution of early whales, it seems the animal was using its arms to propel itself. The bones show the protocetid’s arm had powerful muscles and the ability to bend at the elbow. This suggests the animal used it arms — and presumably legs too — to swim, in a way that could have resembled a modern dog. In truth, it is not clear exactly what ‘stroke’ the animal used. The shoulder bones have not been found, so we can’t tell whether the arm could move sideways or just forwards and backwards. “We don’t know if it’s just crawl or more like butterfly,” says Vautrin.
9-12-19 Bones release a hormone that helps us deal with sudden danger
A hormone secreted by bone helps to coordinate our flight-or-fight response, suggesting our skeletons are more active than we thought. When faced with a sudden threat, our heart and breathing rate, blood pressure, circulating blood sugar and body temperature increase to prepare our muscles to fight or run away. This fight-or-flight response is known to be controlled by direct nerve pathways from the brain and hormones released by the adrenal glands. Now, Gerard Karsenty at Columbia University and his colleagues have discovered that a hormone released by bones called osteocalcin also coordinates this response.They found that blood levels of osteocalcin quickly rose in humans when they had to perform a stressful public speaking task. The same thing happened in mice and rats when they were restrained, given electric foot shocks, or exposed to the smell of fox urine. Additional experiments in mice showed that this osteocalcin surge suppressed the body’s “rest-and-digest” functions in order to allow the opposite flight-or-fight mechanisms to proceed. The results build on the group’s previous work showing that bones release osteocalcin to help the muscles burn fuel during exercise, and that osteocalcin injections in older mice make their ageing muscles more youthful. Together, these findings suggest we need a radical re-think of the role of bones, which have previously been viewed as mostly inert structures, says Karsenty. They may have evolved to protect us from acute danger by activating the flight-or-fight response, optimising muscle function, providing the structural framework needed for our bodies to move and escape, and forming a protective cage around our organs, he says.
9-12-19 50 years ago, polio was still circulating in the United States
Excerpt from the September 13, 1969 issue of Science News. Only eight cases of paralytic polio have been reported in the entire United States so far in 1969. But … if infants and young children are not vaccinated as they come along, pockets of the disease could get larger.
Update: The United States saw its last naturally occurring polio case in 1979. Though the paralyzing disease is now close to being eradicated worldwide, it still circulates in Afghanistan and Pakistan, where 66 new cases were recorded this year as of August 22. Meanwhile, dozens of new cases, mainly in Africa, were caused by vaccine strains that reverted to disease-causing versions. Newer vaccine versions yet to be deployed have a lower risk of causing disease, researchers reported in July in the Lancet. Vaccination campaigns are still needed everywhere, or the disease “will come roaring back,” says Oliver Rosenbauer, spokesman for the Global Polio Eradication Initiative. A resurgence could cause “as many as 200,000 new cases” globally a year.
9-11-19 Dean Burnett on why disruptive teens might have saved the human race
The behaviour that defines teenagers might be annoying, but neuroscientist Dean Burnett says it could have been crucial for the survival of our species. My background and origins were quite a hurdle. I’m from a remote, working-class, former mining community in south Wales. I’m also the first person in my family to show any interest in science. Nobody in academia was actively biased against me, but for many people, that world was familiar. I, by contrast, spent a lot of time figuring it out. By the time I did, it was usually too late. I wouldn’t do this even if I could. I’ve just spent months researching how the teenage brain works. Being given weirdly specific, unsolicited instructions from some older bloke who claims he’s you? Given how most teen brains are geared, that’s likely to make them more willing to do the thing you’re warning against. Teenagers are how they are because it was evolutionarily useful. Long term, sticking to the safe and familiar can lead to stagnation and extinction. Having individuals strike out on their own can refresh the gene pool and uncover useful information. Hence, teens reject authority, crave independence, take risks and so on. Far from being a constant annoyance, teenagers may be the reason humanity is as smart and successful as it is.
9-11-19 Netflix's Diagnosis is a real-life House with added crowdsourcing
Netflix's new show Diagnosis is a moving and powerful attempt to help people with unusual medical conditions find new routes to their longed-for diagnosis. WHEN I heard the premises of two new medical shows that use crowdsourcing to help people with undiagnosed conditions, I was extremely sceptical. The medics have failed you, so why not ask some random people what they think the problem is? As it turned out, I was both right and wrong. The first show, Chasing the Cure, uses a live talk show format to highlight several people seeking a diagnosis. Host Ann Curry asks about their symptoms, while messages and texts arrive, offering support or suggesting diseases. A panel of doctors sifts through the contributions, debunking the (mostly) irrelevant. This portion seemed geared towards increasing viewer and online engagement, rather than finding a diagnosis. But the professional hunt for a diagnosis is also performative, with doctors listing potential causes and crossing out ideas. Tests are done off-screen, but they are rarely referred to. At the end, the doctors join Curry and the participants to deliver their verdict. The tone is odd, with a slick studio, game show music and manipulative interviews that mine the emotions of people in real pain. It makes a spectacle of the tough work doctors do when they diagnose rare diseases. I hated every minute. So I’m not sure why I decided to give Netflix’s Diagnosis a try, but I’m glad I did. It is based on a column for The New York Times Magazine by a doctor, Lisa Sanders, about medical mysteries. In it, she opened up cases to anyone with information to share that could help reach a diagnosis.Each episode is centred on one person. Sanders talks them through her process and shares video messages she receives. Most come from informed sources: medical students who recognise the symptoms, vets who have seen such problems in animals and people who have similar diseases.
9-11-19 Vaping deaths: 'A new generation of nicotine addicts'
Doctors in the US are warning people not to use e-cigarettes as they investigate six deaths linked to vaping. But health experts also say there's a long-term addiction crisis because so many American teenagers are already hooked on nicotine.
9-11-19 Am I addicted? The truth behind being hooked on gaming, sex or porn
Urges to play video games, watch pornography or have sex are now spoken of as addictions. Is the science rigorous, or are we just helping people excuse their behaviour? IAN used to play online video games through the night and into the next day. Over eight years, he lost his job, his home and his family. “I would have told you I loved my children more than anything – and I do love my children very dearly – but the truth is I loved the feeling of going online more,” he says. “It made me feel settled, it was a way to cope and it was a physical craving.” For Ian and others like him, video games feel as addictive as a drug. In May, the World Health Organization (WHO) reached a similar conclusion, including gaming disorder in its International Classification of Diseases for the first time. Studies suggest that between 0.3 and 1 per cent of the general population might qualify for a diagnosis. In the UK, plans are under way to open the first National Health Service-funded internet addiction centre, which will initially focus on gaming disorder. But some argue that to pathologise problematic gaming as an addiction is a mistake. In 2017, a group of 24 academics argued against attributing this behaviour to a new disorder. “Of particular concern are moral panics around the harms of video gaming,” they wrote, which have been seen in the fears around games like Fortnite. Such hysteria, the group argued, could lead to premature or incorrect diagnoses.Others simply claim that addiction to gaming, and to other behaviours such as sex, isn’t real, and that suggesting it is trivialises the issue of addiction or lets people off the hook for their actions. It isn’t surprising that this is a complex issue when you consider that even professionals can’t agree on a definition of addiction. “If you speak to 50 psychologists, we’ll all give you a completely different answer,” says Mark Griffiths, director of the International Gaming Research Unit at Nottingham Trent University, UK.
9-11-19 Giant ice age kangaroos had massive cheekbones for crushing bites
Extinct giant kangaroos had skulls built to deliver the powerful crunch needed to eat tough food, such as branches and stems. This may have allowed them to survive long stretches of time when other food was scarce. Extinct giant kangaroos had skulls built to deliver the powerful crunch needed to eat tough food, such as branches and stems. This may have allowed them to survive long stretches of time when other food was scarce. Short-faced kangaroos lived in Australia during the last ice age and are known for their short snouts, large jaws and teeth, and heavily built skulls. D. Rex Mitchell at the University of New England, Australia, created a digital model of the skull of one type of short-faced kangaroo, the 120-kilogram Simosthenurus occidentalis, and analysed the effects of different biting behaviour. He found that the giant kangaroo had teeth so close to the jaw joints that, if its cheek muscles were proportionate to the tree-kangaroo, a living relative, then the chances of its jaw dislocating were high. “But what I noticed was that this species has absurdly huge cheek bones,” says Mitchell. So when he scaled up the size of the cheek muscles to fit the size of the cheekbones, the digital model showed that the risks of the jaw dislocating dropped substantially. Giant pandas have similarly huge cheekbones that support the same large, stabilising muscles. This suggests the kangaroo may have used their premolars to crunch down on tough plant material, much like pandas eat bamboo, says Mitchell. However, it is also possible that the kangaroos held tough branches in their teeth and pulled them down to break them. The digital model suggests the giant kangaroo could have eaten tougher plants than any currently living Australian herbivores can, says Mitchell. S. occidentalis is thought to have survived until around 42,000 years ago, meaning it possibly lived alongside humans for around 20,000 years.
9-11-19 Artists who paint with their feet have ‘toe maps’ in their brains
Scans of the organ reveal areas that sense individual touches. Two artists who paint with their toes have unusual neural footprints in their brains. Individual toes each take over discrete territory, creating a well-organized “toe map,” researchers report September 10 in Cell Reports. Similar brain organization isn’t thought to exist in people with typical toe dexterity. So finding these specialized maps brings scientists closer to understanding how the human brain senses the body, even when body designs differ (SN: 6/12/19). “Sometimes, having the unusual case — even the very rare one — might give you important insight into how things work,” says neuroscientist Denis Schluppeck of the University of Nottingham in England, who was not involved in the study. The skills of the two artists included in the study are certainly rare. Both were born without arms due to the drug thalidomide, formerly used to treat morning sickness in pregnant women. As a result, both men rely heavily on their feet, which possess the dexterity to eat with cutlery, write and use computers. The brain carries a map of areas that handle sensations from different body parts; sensitive fingers and lips, for example, have big corresponding areas. But so far, scientists haven’t had much luck in pinpointing areas of the human brain that respond to individual toes (although toe regions have been found in the brains of nonhuman primates). But because these men use their feet in unusually skilled ways, researchers wondered if their brains might represent toes a bit differently. The two artists, along with nine other people with no special foot abilities, underwent functional MRI scans while an experimenter gently touched each toe. For many people, the brain areas that correspond to individual toes aren’t discrete, says neuroscientist Daan Wesselink of University College London. But in the foot artists’ brains, “we found very distinct locations for each of their toes.” When each toe was touched, a patch of brain became active, linking neighboring toes to similarly neighboring areas of the brain.
9-11-19 ‘The Nature of Life and Death’ spotlights pollen’s role in solving crimes
A botantist explains the science of forensic ecology. Even if a criminal doesn’t leave behind fingerprints or DNA, detectives need not worry. Crime scenes are peppered with other clues — pollen and spores — that can trip up even the most careful crooks. These clues are central to forensic ecology, in which scientists analyze biological material to help detectives solve crimes. In The Nature of Life and Death, botanist Patricia Wiltshire lays out the science underlying the discipline — which she helped pioneer in the United Kingdom — as she chronicles some of her most memorable cases of the last 20 or so years. Early in her career, Wiltshire used the power of pollen and spores to analyze archaeological sites. The qualities that make these particles useful for studying the past also make them useful for solving crimes. The particles’ natural polymers can be long-lasting, and in certain conditions, pollen and spores persist longer than other forms of evidence, even for thousands of years. More important for detectives, these biological bits are often as distinctive as the plants and fungi that make them, providing telltale clues of where a crime has happened or where a criminal has been. In part because of their minuscule size, pollen and spores are particularly susceptible to static electricity, doggedly clinging to the clothing and hair of victims and perpetrators alike. Criminals often don’t even realize they’re covered in the tiny particles. The combination of pollen and spores at a site can be as distinct as a fingerprint, especially when dealing with rare plants or fungi, or pollen that isn’t spread far and wide by the wind, Wiltshire explains. By studying the material, she has, for example, determined where and during which season crimes have occurred. In one murder case, Wiltshire used pollen and spores from a gardening tool, the tennis shoes of the murderer and the foot pedals of the victim’s car to identify the woodland locale in northern England where the victim’s body had been dumped.
9-10-19 HPV vaccinations seem to be creating herd immunity for US men
Oral HPV infection rates are now 37 per cent lower among unvaccinated US men, suggesting the widespread rollout of the HPV vaccine has led to herd immunity. In the US, vaccinations to protect against the most common types of HPV were first officially recommended for girls in 2006 and for boys in 2011. In addition to causing most cervical cancer, HPV is also linked to some types of mouth and throat cancers. Despite this, little research has been done on the effects of the vaccine on oral cancers, so Anil Chaturvedi at the National Cancer Institute in the US and his colleagues looked at a nationwide survey on HPV infections in the years following the vaccines’ introduction. Almost 14,000 adults took part in the survey, conducted from between 2009 and 2016. Over those years, HPV vaccination rates increased from zero to 5.8 per cent in men and from 7.3 per cent to 15.1 per cent in women. During this period, the prevalence of the types of HPV included in the vaccines dropped from 2.7 per cent to 1.6 per cent in men who had not been vaccinated. This represented a 37 per cent drop among the unvaccinated adult men. This suggested herd immunity was protecting these men, the team wrote. “Herd protection likely arises from increased levels of female HPV vaccination in the US population.” Chaturvedi and his colleagues failed to find a similar protective effect among unvaccinated women in their study. This could be explained by a low prevalence of oral HPV in the women included, they wrote. There are more than 100 different types of HPV, and the current vaccines only protect against the most common and harmful types. The number of men infected with HPV types that were not included in the vaccine remained the same over the study period.
9-10-19 Earliest direct evidence of milk consumption
Scientists have discovered the earliest direct evidence of milk consumption by humans. The team identified milk protein entombed in calcified dental plaque (calculus) on the teeth of prehistoric farmers from Britain. It shows that humans were consuming dairy products as early as 6,000 years ago - despite being lactose intolerant. This could suggest they processed the raw milk into cheese, yoghurt or some other fermented product. This would have reduced its lactose content, making it more palatable. The team members scraped samples of plaque off the teeth, separated the different components within it and analysed them using mass spectrometry. They detected a milk protein called beta-lactoglobulin (BLG) in the tartar of seven individuals spanning early to middle Neolithic times. "Proteomic analysis of calculus is a fairly recent technique. There have been a few studies before, but they have generally been on historical archaeological material rather than prehistoric material," co-author Dr Sophy Charlton, from the department of archaeology at the University of York, told BBC News. Lactose intolerance arises from the inability to digest the lactose sugar contained in milk beyond infancy. This means that consuming milk-based foods can cause uncomfortable symptoms such as abdominal pain, diarrhoea and nausea. However, many modern Europeans possess a genetic mutation which allows for the continued consumption of milk into adulthood. This mutation affects a section of DNA controlling the activity of the gene for lactase - an enzyme that breaks down lactose sugar. However, previous studies of the genetics of Neolithic Europeans show that they lacked this mutation. Dr Charlton said it was possible these Stone Age people were limiting themselves to small amounts of milk. "If you are lactose intolerant and you consume very, very small amounts of milk, then it doesn't make you too ill. You can just about cope with that," she explained. But Dr Charlton added: "The alternative option, which I think is perhaps slightly more plausible, is that they were processing the milk in such a way that it's removing a degree of the lactose. So if you process it into a cheese, or a fermented milk product, or a yoghurt, then it does decrease the lactose content so you could more easily digest it. "That idea fits quite well with other archaeological evidence for the period in which we find dairy fats inside lots of Neolithic pottery, both in the UK and the rest of Europe."
9-10-19 Supercooling tripled the shelf life of donor livers
Chemicals that prevent the human tissue from freezing may help ease organ shortages. A new technique to keep donor organs colder than ice cold could greatly extend the length of time that those organs are viable for transplant. Typically, donor organs stay viable for several hours on ice at about 4° Celsius. Tissue can last even longer at lower temperatures — but below zero degrees Celsius, the formation of ice crystals risks damaging an organ and rendering it unusable. Now, using chemicals that prevent an organ from freezing at subzero temperatures, researchers have preserved five human livers at –4° C. That supercool storage system tripled the livers’ typical shelf life from nine to 27 hours, researchers report online September 9 in Nature Biotechnology. This kind of deep-chill technology “would be huge for transplantation,” says Jedediah Lewis, president and CEO of the Organ Preservation Alliance in Berkeley, Calif., a nonprofit that supports research on organ and tissue preservation but was not involved in this research. Every year, thousands of donor organs are discarded for various reasons, including the inability to find a suitable patient close enough to receive the organ before it goes bad. If donor tissue were viable longer, doctors could get organs to patients who might otherwise be too far away, Lewis says. That could lead to more lifesaving surgeries for patients waiting for a transplant — currently more than 100,000 in the United States alone. Pushing back organs’ expiration dates could also curb the costs of private flights to rush organs between cities and allow for more flexible surgery scheduling, Lewis adds.
9-10-19 A new prosthetic leg that senses touch reduces phantom pain
Agility and confidence while walking increased in two men who tested the device. A prosthetic leg that can feel helped two men walk faster, more smoothly and with greater confidence. The artificial leg, outfitted with sensors that detect pressure and motion, also curbed phantom pain that came from the men’s missing legs, researchers report online September 9 in Nature Medicine. Restoring these missing signals may greatly improve the lives of people who rely on prosthetic limbs (SN: 1/28/11). Neuroengineer Stanisa Raspopovic of EHT Zürich and colleagues tested the device in two men, both of whom had a leg amputated above the knee. Their new prosthetic legs were outfitted with seven sensors that detect foot pressure on the ground and one sensor that decodes the angles of the knee joint. Electrodes implanted on the sciatic nerve, just above the amputation site, then stimulated the nerve with signals from the sensors on the prosthesis. “If you close your eyes, you will think that you have your own leg,” volunteer Savo Panic said in Serbian in a translated video released by the researchers. When those sensory signals were present, the two men walked faster and more confidently, even over difficult sandy terrain. What’s more, unpleasant feelings of pain from their missing leg lessened. After about a month of use, one of the men reported no pain at all, and the other man said his pain was sporadic.
9-10-19 Culture helps shape when babies learn to walk
Motor development models based on Western standards are too narrow. For generations, farther back than anyone can remember, the women in Rano Dodojonova’s family have placed their babies in “gahvoras,” cradles that are part diaper, part restraining device. Dodojonova, a research assistant who lives in Tajikistan, was cradled for the first two or three years of her life. She cradled her three children in the same way. Ubiquitous throughout Central Asia, the wooden gahvora is often a gift for newlyweds. The mother positions her baby on his back with his bottom firmly over a hole. Underneath is a bucket to capture whatever comes out. She then binds the baby with several long swaths of fabric so that only the baby’s head can move. Next, she connects a funnel, specially designed for either boys or girls, to send urine out to that same bucket under the cradle. Finally, she drapes heavy fabric over the handle atop the gahvora to protect the child from bright light and insects. Babies stay in that womblike apparatus for hours on end, with use decreasing as the child ages. When babies fuss, mothers often shush them by vigorously rocking the cradle back and forth or leaning over the side to breastfeed. Besides keeping babies dry and warm, gahvoras provide a sense of safety, Dodojonova says. “It is very nice for children because they are bound and cannot move.” Eventually, they are running and jumping like children everywhere. To the uninitiated, this child-rearing approach may sound odd, or even shocking. Yet cultures should be viewed within their own context, says psychologist Catherine Tamis-LeMonda of New York University. “We engage in practices that fit our needs, our own everyday lives.”
9-10-19 The day the dinosaurs' world fell apart
Scientists have a recording of the worst day on Earth; certainly the worst day in the last 66 million years. It takes the form of a 130m section of rock drilled from under the Gulf of Mexico. These are sediments that were laid down in the seconds to hours after a huge asteroid had slammed into the planet. You'll know the event we're talking about - the one researchers now think was responsible for the demise of the dinosaurs and the rise of mammals. The high-resolution account of this catastrophe was recovered by a UK/US-led team, who spent several weeks in 2016 drilling into what remains of the crater produced by the impact. Today, this 200km-wide structure is positioned under Mexico's Yucatan Peninsula, with its best preserved central portions sitting just offshore of the port of Chicxulub. The team pulled up a great long core of rock but it's a particular 130m-long section that essentially documents the first day of what geologists call the Cenozoic Era, or as some others like to refer to it: the Age of Mammals. 1. A 12km-wide object dug a hole in Earth's crust 100km across and 30km deep. 2. This bowl then collapsed, leaving a crater 200km across and a few km deep. 3. The crater's centre rebounded and collapsed again, producing an inner ring. 4. Today, much of the crater is buried offshore, under 600m of sediments. 5. On land, it is covered by limestone, but its rim is traced by an arc of sinkholes. The section is a nightmarish jumble of shattered material, but its contents are arranged in such a way that scientists say they can discern a clear narrative. The bottom 20m or so, is dominated by glassy debris. This is the rock that was melted by the heat and pressure of the impact. It lapped across the base of the crater in the subsequent seconds and minutes. This then transitions to a lot of fragmented melt rock - the result of explosions as water rushed across the hot material. The water came from the shallow sea covering the area at the time. It would have been pushed temporarily out of the way by the impact but when it came back in and made contact with the broiling rock, it would have set off violent reactions. Something similar occurs at volcanoes where magma interacts with seawater. This phase covers the first minutes to an hour. But the water keeps coming, filling up the crater, and the top 80-90m of the core section is built from all the debris that was in this water and ultimately rained out. Larger fragments initially followed by finer and finer material. The timescale for this is the first hours after the impact. And then, right at the top of the 130m core section is evidence of a tsunami. The sediments all dip in one direction and their organisation suggests they were deposited in a high-energy event. Scientists say the impact would have generated a giant wave pulse that would have crashed on to shorelines hundreds of kilometres from the crater. But this outward train would also have had a return pulse and it's the debris carried in this tsunami that caps the top of the rock sequence. "This is all still Day One," says Prof Sean Gulick from the University of Texas at Austin. "Tsunamis move at the speed of a jet plane. Twenty-four hours is a generous amount of time for the waves to move out and come back in again," he told BBC News.
9-9-19 Transplant organs can be supercooled to below zero for longer storage
The length of time that a liver can be kept outside the body has been extended to a day and a half by a new “supercooling” method, which for the first time has let human organs be safely stored at sub-zero temperatures. The technique, which lowers the organ’s temperature below zero without forming damaging ice crystals, could boost the number of liver transplants carried out and could also be used on other organs, says Reinier de Vries of Harvard Medical School in Boston. There is a shortage of organs available for transplant, with about 14,000 people on the liver waiting list in the US, for example. A big problem is that when an organ becomes available from someone who has died, it can only be stored outside the body, at 4 degrees C, for a short time – up to 12 hours in the case of livers – which limits how far it can be transported. “It’s a race against the clock,” says de Vries. His team has developed a method for cooling livers down to -4 degrees C without them freezing. The organ is connected to a machine that perfuses it with chemicals to lower the freezing point, and air is removed from the storage bag, to avoid ice crystals forming at air-liquid contact points. The method was tested on three human livers that had been made available for transplant but weren’t in good enough condition to use. After the sub-zero storage and rewarming, all three organs seemed to recover well when they were perfused with blood at body temperature, as they started making bile. As the organs are not frozen they cannot be kept below zero indefinitely, but de Vries says they will now try extending the storage period past a day and a half. It could also be used with hearts and kidneys, although lungs would be more difficult because they are filled with air. “The larger the volume of the organ, the more difficult it becomes. Human livers are the largest solid organ.”
9-9-19 An artificial leg with sensors helps people feel every step
An artificial leg has sensors to let people feel when it flexes and lands on the ground – which helps them to walk more quickly and confidently. The first two people to use the new kind of prosthetic legs found they also had less phantom limb pain, the mysterious phenomenon when amputees get rogue sensations that seem to come from their missing limb. Many people with an artificial leg find it hard to use, especially those who have lost their leg above the knee. Part of the problem is that it feeds back no sensations, making it hard to judge its position and motion. Stanisa Raspopovic of the Swiss Federal Institute of Technology in Zürich, Switzerland, and colleagues took a commercially available artificial leg and put sensors on the sole of the foot and inside the knee that could be connected by wires to nerves in the person’s thigh.The team gave two men the chance to test out their legs, by connecting up their nerves to the wires. For the first month they tested the best way to stimulate their nerves to generate the most realistic sensations. “They described it as close to lifelike,” says Raspopovic. Then the men tested out the legs on an outdoor track. Both walked faster with the new limbs than when the feedback was turned off, by up to 6 meters per minute and they felt more confident in the limb. “Being able to perceive the motion of your joints is incredibly important,” says Aadeel Akhtar of the University of Illinois at Urbana-Champaign, who was not involved in the work. “It makes you feel like the prosthetic becomes your own.” Over three months, one man’s phantom limb pain went completely and the other’s fell by 80 per cent. “I would argue that’s an even bigger benefit,” says Akhtar.
9-9-19 Ancient footprints show Neanderthals may have been taller than thought
We know Neanderthals mated with us, painted on cave walls and may have used herbal medications. Now an analysis of the biggest tranche of Neanderthal footprints yet discovered offers a window into their lives. The 257 fossil footprints were found in a coastal creek bed in Le Rozel in northern France. They were made around 80,000 years ago and preserved in sandy mud. Most of the footprints were from children and may show that Neanderthals could have been taller than previously thought. “The discovery of so many Neanderthal footprints at one site is extraordinary,” says Isabelle de Groote at Liverpool John Moores University, who was not involved with the study. Before this, only nine Neanderthal footprints were known, from 4 different sites, says Jérémy Duveau of the Muséum National d’Histoire Naturelle in France, who led the team that carried out the analysis. “Footprints are very interesting because they give a snapshot of a moment of life of hominins such as Neanderthals, and allow us to estimate the size and composition of the group that made them.” This kind of information is hard to obtain from other archaeological artefacts such as skeletons and tools. Although the researchers can’t be certain that the 80,000-year old footprints at Le Rozel were made by Neanderthals, as no hominin skeletal remains were found at the site, Neanderthals were the only known hominins in Europe at that time – Homo sapiens arrived some 35,000 years later. The footprints of Neanderthals are wider than those of modern humans because their feet were broader. From the size of the Le Rozel footprints, the researchers could estimate the size of the individual who made them, and then infer their age.
9-9-19 Defeat malaria in a generation - here's how
The world could be free of malaria - one of the oldest and deadliest diseases to affect humanity - within a generation, a major report says. Each year there are still more than 200 million cases of the disease, which mostly kills young children. The report says eradicating malaria is no longer a distant dream, but wiping out the parasite will probably need an extra $2bn (£1.6bn) of annual funding. Experts say eradication is a "goal of epic proportions". Malaria is a disease caused by Plasmodium parasites. These are spread from person to person by the bite of female mosquitoes in search of a blood meal. Once infected, people become very sick with a severe fever and shaking chills. The parasites infect cells in the liver and red blood cells, and other symptoms include anaemia. Eventually the disease takes a toll on the whole body, including the brain, and can be fatal. Around 435,000 people - mostly children - die from malaria each year. The world has already made huge progress against malaria. Since 2000: 1. The number of countries with malaria has fallen from 106 to 86. 2. Cases have fallen by 36%. 3. The death rate has fallen by 60%. This is largely down to widespread access to ways of preventing mosquito bites, such as bed nets treated with insecticide, and better drugs for treating people who are infected. "Despite unprecedented progress, malaria continues to strip communities around the world of promise and economic potential," said Dr Winnie Mpanju-Shumbusho, one of the report authors. "This is particularly true in Africa, where just five countries account for nearly half of the global burden." Eradicating malaria - effectively wiping it off the face of the planet - would be a monumental achievement. The report was commissioned by the World Health Organization three years ago to assess how feasible it would be, and how much it would cost. Forty-one of the world's leading malaria experts - ranging from scientists to economists - have concluded that it can be done by 2050. Their report, published in the Lancet, is being described as "the first of its kind".
9-9-19 Europeans have steadily accumulated mutations for thousands of years
The number of mildly harmful mutations in the European population has gradually increased over the last 45,000 years, ever since modern humans arrived on the continent. The mutations may be a lingering effect of the original migration into Europe. “These mutations that today are associated with genetic disease do not decrease over time,” says Stéphane Aris-Brosou of the University of Ottawa in Canada. However, while many of the mutations are linked to diseases, their effects are minor and it is unlikely that they are causing the people who have them significant harm. Our species evolved in Africa and only moved into Europe in a big way 45,000 years ago. Geneticists have known for decades that African populations contain much more genetic diversity than non-African groups. This is because the first groups that moved out of Africa were fairly small. To find out how European genomes have been affected by this, Aris-Brosou examined the genomes of 2062 Europeans, including 1179 ancient genomes dating back to up to 45,000 years. For each genome, he looked at 1.2 million sites where a single “letter” on the DNA varies from person to person. Many of these genetic variants have previously been found to be statistically associated with diseases like asthma and diabetes, although their effects are often small: having a single harmful variant would only slightly increase a person’s chances of developing diabetes. Aris-Brosou found that the number of mildly harmful variants in the European population has steadily increased over time. The key factor was probably the small initial populations in places like Europe, which allowed the harmful mutations to become common. “Then it’s very hard to get rid of them,” says Laura Botigué of the Centre for Research in Agricultural Genomics in Barcelona, Spain.
9-8-19 How you live affects your sperm - and perhaps your future children too
Would-be dads take note. Lifestyle choices from smoking to exercise to wearing tight underpants lead to subtle changes in your sperm that may affect the health and behaviour of your children. “What a man does throughout his life has an impact on his sperm,” says Kenneth Aston at the University of Utah. “Those changes may confer risk to offspring.” The focus is usually on mothers when it comes to smoking, but a father’s behaviour also affects his children’s health. One way this can happen is by pregnant women and children being exposed to fathers’ cigarette smoke. However, there is growing evidence that even smoking before conception increases children’s risk of developing a wide range of diseases, from autism to cancers. In part this is because the sperm (and eggs) of smokers have more mutations in their DNA. In 2017, Aston’s team showed that there are also epigenetic changes in the sperm of men who smoke. Epigenetic changes, such as the addition of methyl groups to DNA, don’t change the underlying DNA sequence but can alter the activity of genes. Aston found widespread changes in DNA methylation in the sperm of smokers. What wasn’t clear was whether these changes affect children. In theory, all the methylation changes might be wiped away in developing embryos. So Aston’s team has now exposed male mice to cigarette smoke. The offspring of these mice had altered methylation patterns and altered gene expression in the prefrontal cortex of the brain compared with mice whose fathers were not exposed to smoke. That strongly suggests that the epigenetic changes in sperm due to lifestyle factors such as smoking do indeed affect the health and behaviour of children, the team concludes. Men need to be aware of this, Aston says. “I don’t think many men think about the impacts that their behaviour prior to conception has on their offspring. That’s something I didn’t think about when I was having kids.”
9-7-19 Vaping is suspected in a fifth death and hundreds of injuries
It’s unclear what e-cigarette device or product may be driving the growing number of cases. U.S. health officials have now reported five deaths from severe lung illnesses tied to vaping, with 450 possible cases of these lung injuries reported in 33 states and one U.S. territory. That’s more than double the 215 cases reported a week ago. It’s unclear whether a particular substance vaped or a type of vaping device is behind the illnesses, federal and state health authorities announced September 6 in a news conference. “So far, no definitive causes have been established,” said Dana Meaney-Delman of the lung injury response group at the Centers for Disease Control and Prevention in Atlanta. For now, federal health officials are urging people not to use e-cigarettes, and say that vaping is especially harmful to youth, young adults and pregnant women. The New York State Department of Health is eyeing one possible suspect substance, saying on September 5 that high levels of vitamin E acetate had been found in some vape products containing cannabis. Vitamin E acetate is a dietary supplement and ingredient in some skin care products, but could be toxic when inhaled. But it is still too early to focus on any one substance, federal officials cautioned in the news conference. The Food and Drug Administration is testing more than 120 samples from vaping products for a broad range of chemicals, including nicotine and tetrahydrocannabinol — the psychoactive ingredient in marijuana known as THC — as well as various diluents and additives and even pesticides and opioids. “The samples we’re continuing to evaluate show a mix of results, and no one substance or compound, including vitamin E acetate, has been identified in all of the samples tested,” said Mitch Zeller, director of the FDA’s Center for Tobacco Products in Silver Spring, Md.
9-7-19 The longest Dead Sea Scroll sports a salt finish that the others lack
The treatment may help explain why the Temple Scroll is remarkably bright. Decades after the Dead Sea Scrolls were discovered in desert caves, the ancient manuscripts are still offering surprises. Chemical analysis of the Temple Scroll, the longest of the scrolls, has revealed a salty coating on the text side of the scroll that hasn’t been previously found on the others. This unusual finish suggests that the Temple Scroll’s remarkably bright parchment was manufactured differently from other documents in the collection, researchers report online September 6 in Science Advances. It’s not yet clear how the mineral coating may have contributed to the Temple Scroll’s striking appearance, says Admir Masic, a materials scientist at MIT. But understanding the properties of this manuscript and others like it could inform strategies for preserving these 2,000-year-old documents, which include sections of the Hebrew Bible, as well as help in spotting forgeries. Masic and colleagues scrutinized a small fragment of the Temple Scroll using X-ray and Raman spectroscopy. These techniques involve shining radiation on a sample and measuring the light that emanates back out to map the material’s chemical composition. “This surprise came out, of salts that we weren’t expecting to find at all,” Masic says. The mixture atop the Temple Scroll mostly comprises sulfate salts, including minerals like gypsum, glauberite and thenardite, not previously seen on the Dead Sea Scrolls (SN: 11/17/17). “Sometimes you find a lot of inorganic components on these scrolls or fragments, and they probably came from the caves,” Masic says. But since the minerals on the Temple Scroll aren’t generally found in the region around the Dead Sea, it’s more likely that these materials were used in the scroll’s production, the researchers conclude.
9-6-19 Two people have died from lung disease after vaping – what’s going on?
Two deaths in the US have now been attributed to vaping-related lung conditions, and state governments are taking actions to crack down on the types of e-cigarettes available. Here’s what you need to know about this mysterious illness and the response to the outbreak. In July, an Illinois resident developed a lung infection and died after using a vaping device that contained marijuana oil. Yesterday, officials in Oregon said that a resident of the state who used e-cigarettes had also died after being hospitalised for a severe lung infection. It’s not clear why these respiratory problems led to the people’s deaths. It could be that something either in the e-cigarette or the substances smoked through them caused serious inflammation of the lungs. The US Centers for Disease Control and Prevention (CDC) says that as of 27 August, 215 possible cases of vaping-related severe lung disease have been reported by 25 states. In addition to the deaths in Illinois and Oregon, this multistate outbreak includes people who have reported coughs, shortness of breath, chest pain, fever, fatigue, nausea, vomiting and diarrhoea. These symptoms developed over days or weeks. Some people turn up to hospital with symptoms that look like pneumonia, and have been put on ventilators or treated in intensive care units. We’re not certain, but there could be a connection. In every one of these cases, people reported using e-cigarettes. But no single e-cigarette product or substance has been associated with all the illnesses. The CDC says that recent inhalation of cannabis products and THC, the main psychoactive compound in marijuana, has been reported in many patients from two states.
9-6-19 Why do fragrances cause health problems for one in three people?
One in three adults say that fragranced products cause them health problems, and one in ten say the effects are so bad that they have missed work or lost jobs, suggests a survey of over 4000 people. But it is unclear whether the symptoms people experience are direct physiological responses, or whether they have a psychological component. Fragrances are used to mask smells or add a nice aroma in to a wide range of products, including in many cosmetics, cleaning supplies, air fresheners, laundry detergents and soaps. Previous surveys have found that people believe they experience a range of health issues when exposed to such fragrances. An increasing number of people are describing themselves as having “chemical sensitivity”, in which low levels of chemicals in their everyday environment trigger a diverse range of symptoms. But little is known about what may be causing these problems. To get a better understanding of how common fragrance sensitivity is and how it affects daily life, Anne Steinemann at the University of Melbourne, Australia, surveyed around 1100 nationally representative individuals each from the US, Australia, the UK and Sweden. These were randomly recruited from a research survey database of over six million people. One in three respondents said fragranced products affected their health. The highest rate of issues was in the US, where nearly 35 per cent reported problems with fragrances. The lowest reported incidence was in the UK, where nearly 28 per cent of respondents said they were adversely affected by fragrances. One in five respondents said their health had been affected by being near someone wearing a fragranced product, while one in six said they experienced health problems around air fresheners or in rooms cleaned with fragranced products.
9-6-19 DNA indicates how ancient migrations shaped South Asian languages and farming
An analysis of more than 500 skeletons reveals the genetic and cultural ancestry of the region. A new DNA study of unprecedented size has unveiled ancient human movements that shaped the genetic makeup of present-day South Asians in complex ways. Those long-ago treks across vast grasslands and through mountain valleys may even have determined the types of languages still spoken in a region that includes what’s now India and Pakistan. The investigation addresses two controversial issues. First, who brought farming to South Asia? Genetic comparisons indicate that farming was either invented locally by South Asian hunter-gatherers or launched via borrowing of knowledge from other cultures, rather than brought by Near Eastern farmers from what’s now Turkey. No DNA signs were found of those farmers, who earlier studies suggested had brought farming to Europe. Second, where did local languages originate? New DNA evidence supports the idea that mobile herders from Eurasian steppe grasslands, not Near Eastern farmers, brought Indo-European languages to South Asia. Ancient DNA had already suggested that Indo-European speaking Eurasian herders called the Yamnaya reached parts of early Bronze Age Europe by around 5,000 years ago (SN: 11/15/17). Yamnaya-related ancestry appeared among South Asians between around 3,900 and 3,500 years ago, an international team reports in the Sept. 6 Science. “By the early Bronze Age, human movements were stirring the genetic pot throughout Asia,” says archaeologist Michael Frachetti of Washington University in St. Louis. He led the massive project along with Harvard Medical School geneticists David Reich and Vagheesh Narasimhan and archaeologist Ron Pinhasi of the University of Vienna.
9-6-19 Jurassic turtle may have been crushed underfoot by a giant dinosaur
It brings a whole new meaning to the word shellshock. A Jurassic turtle seems to have been squashed flat before it was fossilised – possibly because a giant dinosaur trod on it. The marine turtle fossil was found in 2007 in Switzerland, as part of a project to study fossils that had been revealed by the construction of a highway. It dates from about 155 million years ago in the late Jurassic period. The dinosaurs were at their height then, and huge, long-necked sauropod dinosaurs dominated the land. Most turtles from the time are found in marine sediments, but this one was on land. “It’s like a tidal flat, where we mostly found dinosaur prints and tracks,” says palaeontologist Christian Pu¨ntener, who was employed by the Republic and Canton of Jura in Switzerland to study the fossils. Finding the turtle there is significant, he says, because previously there was no hard evidence that Jurassic marine turtles ventured onto land. The turtle was on its back, which suggests it had become stuck on the tidal flat and died there, says Pu¨ntener. It’s not clear what it was doing there. One possibility is that it came ashore to lay eggs, as marine turtles do today, but it is unclear if the animal was male and female, and if the tidal flat was a nursery there ought to be more turtle fossils. However, the most striking thing about the turtle is the state of the fossil. Most of it is unusually flat. Seen from the side, a big chunk of it is visibly lower than the rest in the rocks. “The main shell part is pushed down, relative to the posterior part,” says Pu¨ntener. This suggests a heavy weight crushed much of the shell.
9-5-19 Drug cocktail seems to reverse biological signs of ageing in people
Is this the world’s first anti-ageing drug? Scientists have made people younger for the first time, or so they think. Nine men took a year-long drug regime that appeared to reverse the ageing process, leaving them one-and-a-half years younger – biologically – than when they started. The clinical trial was the first to investigate the possibility that a drug might be able to reverse the biological signs of ageing, increasing lifespan. However, the results are limited by the fact that this was a feasibility study without a placebo. The men, aged 51 to 65, took a drug cocktail involving recombinant human growth hormone (rhGH), three to four times a week for a year. At the beginning and end of the trial they had their biological age measured. We all have a chronological age – the number of candles on our birthday cake – and an epigenetic, or biological age, which is a measure of how quickly the cells in our body are deteriorating compared with the general population. These two figures can differ, and our epigenetic age is often a better predictor of lifespan. The researchers used four different tests of epigenetic age. On average, across the four tests, the volunteers’ epigenetic age was 1.5 years younger than it was at the beginning of the treatment. This means someone who had an epigenetic age of 55, say, at the beginning of the trial had an epigenetic age of 53.5 at the end of the year-long trial. The most advanced test, “GrimAge” – named after the Grim Reaper – showed a 2-year decrease in epigenetic versus chronological age that persisted six months after the men stopped taking the drug therapy.
9-5-19 Tyrannosaurus rex had 'air-con' in its head
As a big, active predator, the mighty Tyrannosaurus rex needed a way to cool down. Now, scientists say that two large holes in its skull acted as a kind of internal "air-conditioning unit", to help the dinosaur lose heat. These anatomical features on the top of the head were previously thought to have been filled by muscles. But a team says it's more likely this area was filled with blood vessels that helped T. rex regulate its temperature. Large animals need special ways to cool down, since their immense body heat can overwhelm them in hot conditions. Casey Holliday, from the University of Missouri, and colleagues, used thermal imaging devices - which translate heat into visible light - to examine alligators at the St Augustine Alligator Farm Zoological Park in Florida. "It's really hard to get a picture of an alligator skull in the wild, because they're always off away from you and they're dangerous to approach," he said. "Being at the farm allowed us to get up and over fences and take images and video from the top down." They discovered that the alligators have blood-vessel-filled holes in their skulls. "An alligator's body heat depends on its environment," said co-author Kent Vliet, from the University of Florida in Gainesville. "We noticed when it was cooler and the alligators are trying to warm up, our thermal imaging showed big hot spots in these holes in the roof of their skull, indicating a rise in temperature. Yet, later in the day when it's warmer, the holes appear dark, like they were turned off to keep cool." By examining fossils and 3-D images of Tyrannosaurus rex's skull, the scientists discovered that the dinosaur had similar holes. In the past, scientists believed the two large features in the roof of the extinct predator's skull - called the dorsotemporal fenestra - were filled with muscles that assist with jaw movements.
9-4-19 The psychobiotics revolution has implications for us all
The discovery that gut bacteria can boost our mood may herald a new way of treating mental health conditions. “KILLS all known germs” was once an effective advertising slogan. Now we know this promise isn’t as desirable as it might sound. Not all “germs” are bad. In fact, you couldn’t survive without help from the many microbes that live on and within you. A thriving microbiome isn’t just essential for your physical health, though. In the latest twist to this story it turns out that microbes in your gut also influence your mood. These so-called psychobiotics are intimately entwined with us from birth. They help shape the developing human brain, particularly the areas associated with emotions. They also exert day-to-day control over how we feel. The mystery of how single-celled organisms have an effect on our minds from a distance is starting to be solved (see “How what you eat directly influences your mental health”). Intriguingly, bacteria in our intestinal tract can produce almost all the same neurotransmitters we generate in our brains, and they have a hotline from the gut to the head. As yet, we don’t know exactly which microbes influence our moods. Still, we know enough about psychobiotics to start to benefit from them. Experiments show that consuming certain probiotic foods can help people cope with anxiety and depression, the most common causes of disability worldwide. With more research and a better understanding of the bacteria involved, psychobiotics look set to offer a real alternative to drugs and cognitive behavioural therapy for a range of mood disorders. Some will find this liberating, because it offers hope of taking back control from a mental health condition. But the psychobiotics revolution has implications for all. Anyone can cultivate feel-good bacteria in their gut with the right kind of diet (see “Healthy gut, happy mind: What to eat to boost how you feel”). You really can eat yourself happier.
9-4-19 The world is getting better, so why are we convinced otherwise?
We need a better handle on our ignorance if we want to improve our lives, says Ola Rosling, a proponent of factfulness - holding only opinions supported by strong facts. OLA ROSLING isn’t afraid to point out your mistakes. He is the president of Gapminder, the foundation he set up with his wife Anna Rosling Rönnlund and his late father Hans Rosling. Gapminder is dedicated to exposing common misconceptions about the world and promoting a fact-based viewpoint. The foundation uses data visualisations and quizzes to reveal how little we really know, asking people things like whether they believe the world is getting better or worse, and what they think is the average life expectancy for people globally. He also advocates a “factfulness” mindset, one that seeks to overcome our brain’s inbuilt biases. These arise from the mental “rules of thumb”, known as heuristics, that we use to make decisions, and are responsible for our tendency to notice bad events rather than good ones, and to assume that some things are destined to happen. You may have already seen Ola Rosling’s work via his father’s TED talks. The first, given in June 2006 on “the best stats you’ve ever seen“, has now been viewed more than 16 million times. Last year, the trio behind Gapminder published Factfulness – a book that identifies the common pitfalls that make us see the world as a scary place. It became a global bestseller.For some reason, historically, it was beneficial to worry about everything, to see problems and plan for disaster. It was the way previous generations could survive. We are their offspring, so we tend to use the same tactics, except that we don’t need them anymore. I am not a researcher in these fields, but it seems like humans are predisposed to focus on the negative things we hear, to see problems. (Webmaster's comment: With all these mass killings by White Supremacists the world is better?)
9-4-19 A single severe head injury can trigger long-term brain damage
One major blow to the head is enough to trigger progressive brain deterioration and long-term cognitive decline in some people. We already know that repeated head knocks – like those sustained in boxing and American football – can lead to personality changes, cognitive problems and depression years later. This condition – known as chronic traumatic encephalopathy (CTE) – is associated with gradual build-up of a protein called tau in the brain. David Sharp at Imperial College London and his colleagues wondered if similar brain changes can occur after one bad head injury. To find out, they scanned the brains of 21 men and women who had a single major head injury 18 to 51 years ago in a car accident, assault or fall. They all experienced severe initial symptoms like loss of consciousness for more than 30 minutes, and many have since developed problems with thinking, memory and motivation. The scans revealed that 15 of the participants have unusually high levels of tau protein in their brains, particularly in the outer layers. This is probably because the outer layers are most vulnerable to external impacts, Sharp’s team writes. The amount of tau in their brains didn’t seem to relate to symptom severity, but the study may have been too small to detect this relationship, say the researchers. High levels of tau have also been found in the outer brain layers of former athletes with CTE, particularly in those who have had the most head blows. This is consistent with the idea that brain deterioration can come from either several relatively minor brain injuries or from a single particularly severe one, writes the team.
9-4-19 Vegetarian diet linked with 22 per cent lower risk of heart disease
Eating a vegetarian diet rather than consuming meat has been linked with a significantly lower risk of coronary heart disease. While the environmental case for going vegetarian is unequivocal and powerful, the long-term health impacts of adopting a vegetarian or vegan diet are still poorly understood. To help fill the gap, Tammy Tong at the University of Oxford and her colleagues grouped 48,000 people in the UK by diet and followed them over 18 years. The results showed vegetarians had a 22 per cent lower risk of heart disease than their meat-eating counterparts. The finding, which is in line with some previous research, could be explained by vegetarians generally having lower cholesterol levels. But the analysis has a sting in the tail: vegetarian diets were also associated with a 20 per cent high risk of stroke than that seen in meat-eaters. The reason could be vegetarians missing out on some nutrients only found in meat, such as the B12 vitamin. But that deficiency can be addressed with supplements, says Tong. While that might give people pause before joining the UK’s estimated 1.7 million vegetarians and vegans, Tong says it’s important to look at absolute numbers. Over a ten-year period in the cohort she studied, vegetarians had 10 fewer cases of heart disease per 1000 people than meat-eaters, but just three more cases of stroke per 1000. “You can say the lower risk of heart disease does outweigh the higher risk of stroke in this cohort,” she says.Mark Lawrence and Sarah McNaughton of Deakin University, Australia, writing in a commentary in the BMJ, say the stroke risk should be kept in perspective, as it is a result from just one study and the increase is modest relative to meat-eaters.
9-4-19 All languages, however different, convey information at the same rate
Human speech conveys information at 39 bits per second on average. That might not sound terribly impressive in an age where electronic devices exchange millions of bits of information per second, but it seems to be the optimum rate for people whatever language we speak. Francois Pellegrino’s team at the University of Lyon in France analysed 17 languages, from English to Japanese, that vary greatly in terms of the number of basic sounds, the number of syllables, the use of tones and so on. For instance, there are 7000 distinct syllables in English compared with just a few hundred in Japanese. The team worked out the information density of each language, in terms of bits of information per syllable. This varies from 5 bits per syllable for Basque to 8 bits per syllable for Vietnamese. Next, the team got 10 native speakers of each language – 170 people overall – to read 15 equivalent texts. What they found was that while the speech rate – in terms of syllables per second – varied from speaker to speaker, those speaking more information-dense languages speak more slowly on average. For instance, Basque was spoken at a rate of 8 syllables per second on average while Vietnamese was spoken at 5 syllables per second, making the rate at which information is conveyed similar for both. “There’s this pretty strong push to go for an optimal information rate,” says team member Dan Dediu. “We all have similar brains and we all have similar articulatory organs, so there are universal constraints.” Just what imposes these constraints isn’t clear. It might be due to the effort of speaking, or of understanding speech, or be related to the frequency of brainwaves, Dediu says.
9-4-19 This ancient Denisovan finger bone is surprisingly humanlike
Yet the extinct hominids had closer genetic ties to Neandertals than Homo sapiens. A newly described Denisovan finger fossil holds a skeletal surprise, adding to the mystery of this extinct Stone Age crowd. A decade ago, scientists found a tiny fragment of a fossil pinkie bone in Siberia’s Denisova Cave. That bone yielded the first known Denisovan DNA and helped identify the hominids (SN: 8/30/12). Now paleogeneticist E. Andrew Bennett of Paris Diderot University and colleagues say they’ve identified the rest of the finger bone, which comes from the right hand of a roughly 13-year-old female Denisovan. Unexpectedly, this ancient digit looks more like corresponding bones of ancient and recent humans than of Neandertals, the scientists report September 4 in Science Advances. Yet Denisovans, who inhabited parts of Asia from around 300,000 to 50,000 years ago, had closer genetic ties to Neandertals than to Homo sapiens (SN: 5/1/19). The new finding raises the possibility that other yet-to-be-found Denisovan body parts may be largely humanlike. (Aside from the finger, only teeth, a partial jawbone and part of a braincase have been found so far.) As a result, Bennett’s team recommends caution in trying to identify Denisovan fossils based on shape alone. Russian scientists unearthed the newly identified finger fossil in 2008 in Denisova Cave. Then they cut the specimen into two the next year and sent the pieces to separate DNA-research teams. Bennett’s group matched mitochondrial DNA extracted from one finger segment to mitochondrial DNA already taken from the smaller Denisovan finger fragment, indicating that the bones came from the same individual. Mitochondrial DNA is typically inherited from the mother.
9-4-19 540-million-year-old worm was first segmented animal that could move
An extinct creature that looked like a cross between a millipede and an earthworm was one of the first animals that could move under its own power. The animal has been named Yilingia spiciformis. It was up to 27 centimetres long and up to 2.6 cm wide. Its body was divided into many segments, each carrying two spiky appendages. It looked a bit like an ear of wheat. The fossils were found in the Dengying Formation in southern China. They are between 551 and 539 million years old. This was the Ediacaran period, when the first confirmed multicellular animals appear in the fossil record. Before the Ediacaran, life on Earth seems to have been almost entirely single-celled, but after the Ediacaran, complex plants and animals flourished. Alongside 35 fossils of Y. spiciformis, the rocks also yielded 13 trace fossils: tracks that were left behind by the animals as they moved along the sediment on the seabed. One body fossil was actually found right next to its tracks, offering hard evidence that Y. spiciformis was able to move. “It is the first segmented animal that has been shown to be capable of directional movement,” says Shuhai Xiao at Virginia Tech. Xiao says that Y. spiciformis isn’t quite the oldest animal that could move from A to B. “The first mobile animal is probably about 565 million years old,” he says. One such creature was the slug-like Kimberella, which could slither across the sea floor. Other Ediacaran animals like Dickinsonia could probably move in a less directed way, by letting the water current take them, says Xiao. The new fossils will help us understand how animals evolved the ability to move, says Xiao. “When we look at the animal family tree, clearly animals started as non-motile organisms,” he says. These early, stationary animals may have resembled modern sponges. “The question then becomes, when did animal motility evolve, and whether it evolved once or several times among animals.”
9-4-19 Healthy gut, happy mind: What to eat to boost how you feel
The deep connection between our guts and brains gives us ways to eat ourselves happier – and a few simple changes make all the difference, says dietician Megan Rossi. Megan Rossi is a research fellow at King’s College London and a dietician and founder of the Gut Health Clinic at Harley Street in London. Her background as a clinical dietician and sports nutritionist in Australia helped her realise the depth of the link between what we eat, the bacteria in our gut and how we feel, subjects she now researches at King’s. Her book Eat Yourself Healthy is published on 19 September. Megan will also be appearing at New Scientist Live in London on 12 October to talk about we can better look after our gut health. It made me laugh when you said in your book that “intimate kisses” can transfer bacteria between partners. Are there consequences? There are millions of bacteria in our saliva, so we’d like to see if these impact our partners’ health in some way. In observational studies, there’s an increased risk of being obese if you have an obese partner. Of course, this may just be down to your shared eating environment, but there’s a theory that you might also be sharing bacteria that are associated with obesity.It has been known for ages that there is a connection between our gut and brain via nerves, but now there is a new player, gut bacteria. They communicate with the brain in three different ways: they send signals up the vagus nerve directly into the brain; they influence immune cells in the gut, which produce a range of chemicals that affect the brain; and they produce chemicals that travel in the blood. Some can get through the blood-brain barrier to the brain. And it works in both directions.
9-4-19 Gut feeling: How a healthy microbiome helps beat stress and lift mood
The microbes in our guts have a surprising influence on our brains. Now we're understanding why – and how to use them to combat anxiety, stress and depression. REMEMBER the last time you had a stomach bug and just wanted to crawl into bed and pull up the covers? That is called “sickness behaviour” and it is a kind of short-term depression. The bacteria infecting you aren’t just making you feel nauseous, they are controlling your mood too. It sounds absurd: they are in your gut and your feelings are generated in your brain. In fact, this is just an inkling of the power that microbes have over our emotions. In recent years, such organisms in the gut have been implicated in a range of conditions that affect mood, especially depression and anxiety. The good news is that bacteria don’t just make you feel low; the right ones can also improve your mood. That has an intriguing implication: one day we may be able to manipulate the microbes living within our gut to change our mood and feelings. It is early days, but the promise is astounding. The World Health Organization rates depression and anxiety as the number one cause of disability, affecting at least 300 million people worldwide. The new findings challenge the whole paradigm of mental illness being caused by a chemical imbalance in the brain, and offer an alternative to drug treatment. You’ve probably heard of probiotics, but these are their new incarnation – psychobiotics. They could be about to change the mood of the planet. Bacteria have been associated with sickness almost since they were discovered 350 years ago by Dutch biologist and microscope pioneer Antonie van Leeuwenhoek. Only recently have we begun to understand that microbes also contribute to our health. They produce vitamins and help us eke out extra energy from otherwise indigestible food, for example. Most importantly, by outcompeting and directly battling pathogens, our home-grown microbes protect us from disease.
9-4-19 Pancreatic cancer tumors attack the blood vessels that deliver chemo drugs
New insights into how pancreatic cancer spreads could lead to more effective treatments. Pancreatic cancer is nearly impossible to treat. New research now shows this may be because its tumors destroy the surrounding blood vessels that doctors typically rely on to deliver anti-cancer drugs. Armed with this new knowledge, researchers have zeroed in on how the tumors kill neighboring blood vessel cells. When the team knocked out part of a molecular messaging system underlying the tumor’s deadly progression, its growth slowed, and the density of surrounding blood vessels increased both in mice and in human cells in a dish, the team reports August 28 in Science Advances. A drug that does the same thing in humans “could rescue the blood vessels around the tumor and allow us to deliver drugs to the patient that would shrink the tumor mass, which is currently impossible to do,” says Duc-Huy Nguyen, a molecular biologist at Weill Cornell Medicine in New York City, who did the research while at the University of Pennsylvania. Pancreatic cancer is among the deadliest cancers: More than 90 percent of the estimated 56,770 Americans who will be diagnosed with the disease in 2019 are predicted to die within five years. Cancer of this sweet potato–sized organ has long puzzled researchers. The tumors appear to spread via the bloodstream, yet the tumors themselves have little to no blood supply. Understanding how pancreatic cancer grows and spreads throughout the body has proven difficult because the pancreas is nestled deep in the belly, just behind the stomach. Monitoring a tumor or removing sections of it for study requires cutting the patient open and weaving through other vital organs, increasing the risk of infection or other complications.
9-4-19 Liquid mouth drops could one day protect people from peanut allergies
The treatment may rival a similar approach that involves swallowing the food. A no-fuss immune therapy involving liquid drops placed under the tongue could protect people with peanut allergies from reacting if exposed. Results from a small study of the treatment — called sublingual immunotherapy, or SLIT — rival those of a similar treatment that also builds allergy tolerance by exposing sufferers to small, daily doses of an allergen, researchers report September 4 in the Journal of Allergy and Clinical Immunology. But in that approach, called oral immunotherapy or OIT for short, doses are swallowed rather than administered under the tongue (SN: 11/18/18). The question with SLIT “was always about efficacy,” says Brian Schroer, director of allergy and immunology at Akron Children’s Hospital in Ohio, who was not involved with the research. The new study “shows it’s pretty much equivalent to OIT in terms of protection from accidental food exposures,” he says. SLIT’s delivery method through the mouth’s mucous membrane means that much smaller doses can be used than with the oral treatment, says Edwin Kim, a pediatric allergist and immunologist at the University of North Carolina’s School of Medicine in Chapel Hill. SLIT also produced milder side effects, such as a mouth itch that lasted for up to 15 minutes, compared with OIT, which occasionally has caused allergic reactions that required epinephrine, Kim and colleagues report. And while patients need a two-hour rest period after taking the oral treatment, those receiving a sublingual dose need only hold it under their tongues for two minutes. And “then you’re in the clear to go about your day,” Kim says.
9-3-19 Battle of Worcester artefacts unearthed for first time
Artefacts from the site of the final battle of the English Civil War have been unearthed for the first time. Musket balls, horse harness fittings and belt buckles were found at the Battle of Worcester site in Powick, Worcestershire. Historians have always known the area was the site of the 1651 battle, but it is the first time physical evidence has been recovered. The artefacts will now be analysed and recorded. Archaeologists were able to explore an area of land close to Powick Church while the Worcester Southern Link Road is being built. They had hoped to find artefacts as there is shot damage on the church tower, while Powick Bridge was reportedly the location of intense fighting. The 98 finds were buried deep at the bottom of a river valley and covered by flood deposits accumulated over hundreds of years since the battle. They included a powder container cap, which would have been the top of a flask that held gunpowder, and an impacted lead shot - a lead ball fired from a musket. The finds show the battlefield site was further south than previously thought. Archaeologists said different artefacts were found in different areas of the battlefield, reflecting the different types of troops that would have been fighting. For example, more pistol shots were found in one area, reflecting cavalry, while musket shots were found in another area, reflecting infantry. Richard Bradley, on-site lead archaeologist, said it was "fantastic" to be able to locate and map physical remains of the battle. "We are just outside the registered battlefield area but this is still a nationally significant site," Mr Bradley said. "The construction work has given us the opportunity to investigate the floodplain across which thousands of infantry and cavalry engaged, and to get down to the level where artefacts were deposited.
9-2-19 Bananas have benefited from climate change – but they won’t in future
Climate change has been relatively kind to banana suppliers so far – but in the decades to come, friend may turn to foe. Temperatures are likely to get so hot that the annual production gains enjoyed by banana suppliers will begin to drop. And in some places, total banana yields will begin to decline. Bananas are a staple crop for millions, and one of the world’s top 10 crops in terms of the cultivated area devoted to their growth and the calories they provide to the global population. For the past 60 years, annual yields have been increasing by 1.37 tonnes a hectare as the world warms, and now stand at about 10-40 tonnes per hectare. But a new study by Dan Bebber at the University of Exeter, UK, and his colleagues suggests that as climate change continues, annual yield gains will begin to slump. By 2050, they may be down to 0.19-0.59 tonnes per hectare. “Bananas can take it pretty hot,” says Bebber. “But some of our big suppliers are under serious threat, particularly in Latin America.” India and Colombia will be so badly affected that total annual banana yields will begin to fall, he says. Bebber and Varun Varma of the National Centre for Biological Sciences in Bangalore, India, built a model of optimal conditions for banana production, based on databases from 27 countries stretching back to 1961, combined with temperature and rainfall records. Globally, the ideal average temperature for the crop appears to be 26.7°C, but the best level varies from country to country. Temperatures in the future were assumed to follow two of the UN climate science panel’s worst scenarios. Bananas are cheap in high income countries, so producers are likely to be badly affected by any change in production yields.
9-2-19 'Mission Jurassic' fossil dinosaur dig closes for winter
Three full truck loads of dinosaur fossils were shipped out of the "Mission Jurassic" dig site in North Wyoming as scientists brought the 80-day excavation season to an end. The specimens included skeletal parts from giant herbivorous sauropods and meat-eating theropods. The fossils will now be cleaned to see precisely which species they represent. Mission Jurassic is a major undertaking involving researchers from the US, the UK and the Netherlands. It is led by The Children's Museum of Indianapolis (TCMI) which has taken out a 20-year lease on a square mile (260 hectares) of ranch land. The BBC was given special access to the site in July. The fossil beds exposed at the secret location in the Big Horn Basin record dinosaur activity around 150 million years ago - and the summer's work confirms the site is particularly rich. One three-tonne block of rock lifted on the final day last week was embedded with multiple remains all stacked one on top of the other. "Overall we must have moved something like 500-600 bones; it's just a huge amount of material we've been able to shift in one year," said Prof Phil Manning, a University of Manchester palaeontologist and TCMI scientist in residence. The Children's Museum has been working the site with teams from Manchester, London's Natural History Museum and Leiden's Naturalis Biodiversity Centre. They've been scraping back the layers in two pilot quarries. One of these appears to be a watering hole where various different animals congregated. Not only are their bones preserved in the sediments but so too are the footprints they made as they sploshed through muddy ground. "We have astounding trackways now - over a hundred individual tracks from different creatures. It's pretty cool because we see evidence of the animals when they were dead and when they were alive," Prof Manning told BBC News.
9-1-19 CRISPR could lead to gene-editing fix for a form of male infertility
Male mice with a mutation that prevented them producing any sperm have fathered offspring the natural way after a team in China fixed their infertility by CRISPR genome editing. The technique could one day help many infertile men around the world. “I think this study is very exciting,” says Sarah Vij, a male infertility specialist at Cleveland Clinic Foundation in the US, who was not involved in the work. “Most of us think this is the future for these men.” There are several known genetic mutations that prevent the stem cells in the testes giving rise to healthy sperm. Some men still have non-moving sperm cells in the testes that can be surgically extracted and injected into eggs. But this doesn’t always work, and children created this way risk inheriting the mutation that made their father infertile. So for decades biologists have been exploring ways of correcting these mutations. In 2015, for instance, one team showed that they could restore the ability of mice stem cells to produce healthy sperm by using CRISPR genome editing to correct the underlying genetic mutation. Now Xiaoyu Li’s team at the Affiliated Hospital of Guangdong Medical University has taken this work a step further by taking stem cells from a mouse, correcting the mutation and implanting them back in the same mouse. Four months later, the mice mated with females, and 9 out of 11 fathered healthy offspring. However, there is still a way to go before trying this in people. The biggest obstacle, says reproductive expert Geert Hamer of the University of Amsterdam, is that there is no reliable way of isolating human sperm stem cells. Another issue is that in some cases it might be necessary to kill off the mutant stem cells in the testes to prevent them competing with the corrected ones, Hamer says. This would likely require chemotherapy or radiation, so developing lab-grown sperm and using it for IVF might be a safer approach.
9-1-19 Giant virus has evolved its own kind of CRISPR to destroy invaders
The mimivirus is so enormous it has its own kind of CRISPR-like immune system to defend against the smaller viruses that attack it. A team in France has confirmed how it works by transferring the entire system to a bacterium and tweaking it to destroy a different target. While CRISPR has become famous as a tool geneticists can use for editing genomes, it evolved in bacteria as a way of defending against viruses. The bacteria “cannibalise” bits of DNA from the viruses that attack them and add this DNA to their own genomes. The CRISPR system allows the bacteria to recognise and destroy any matching viral DNA the next time they get attacked. In other words, CRISPR acts like an adaptive immune system. In 2016, Didier Raoult of Aix-Marseille University in France sparked controversy when he claimed that a giant virus called mimivirus had independently evolved its own adaptive immune system that works in a similar way to CRISPR, dubbed MIMIVIRE. Giant viruses are strange entities first identified in 2003. Like all viruses, they cannot multiply independently but rely on hijacking other organisms. But while most viruses are little more than protein shells containing DNA or RNA, giant viruses have lots of active cellular machinery inside them, such as protein-making factories. They are so complex they are even plagued by their own viruses, or virophages. The first virophage was discovered by Raoult in 2008. His team also discovered that one strain of mimivirus is immune to a virophage called zamilon. This mimivirus strain has bits of zamilon DNA integrated into its genome, which it uses to recognise and chew up the DNA of invading zamilon virophages. But critics questioned the claim that the mimivirus has its own kind of adaptive immune system. So Raoult has now transferred the MIMIVIRE system to the E. coli bacterium. Crucially, the team swapped the zamilon sequences for bits of a bacterial gene. When they activated MIMIVIRE, that bacterial gene got chewed up. “We changed the target,” says Raoult.
9-1-19 How a deer-tooth necklace helps us to better understand our ancestors
Ice Age Europe, approximately 20,000-13,500 years ago; a period known as the Magdalenian. The climate is gradually ameliorating after glaciers and cold temperatures reached their height in the Last Glacial Maximum. Despite this, the landscape is frozen, arid, and unforgiving for all who live within it. Dispersed and highly mobile hunter-gatherers populate this harsh environment. These Magdalenian people adapted to the landscape by using all available resources to create a rich and diverse material culture, which included tools, highly efficient hunting projectile weapons, tailored clothing, cave art, portable art, beads, and much more. All aspects of this culture depended on relationships with other human groups, and an intimate knowledge of animals that were a crucial resource during this period, enabling the Magdalenian people to survive. It is these relationships, how they were maintained by these people, and how they shaped past identities and social behaviors, that are the key to better understanding our ancestors' social lives and behaviors. During this period, around 19,000 years ago in southwestern France at a site called Saint-Germain-La-Rivière, an adult woman dies and is prepared for burial by members of her society. She is adorned with 70 red-deer teeth that were perforated by a flint tool to be used as beads; many of which have a unique engraved design and were smeared with red ocher. These beads provide a window into the period, giving an insight into the way our Magdalenian ancestors negotiated relationships, and the importance of this meshwork of relations to their survival. The burial context of these beads demonstrates how these relations took center stage in the social lives of Magdalenian people. Untangling the object biographies of these beads — the way they were made, used, and deposited — can reveal the creative ways our ancestors used objects to negotiate and embody intricate human-animal-object-landscape relationships. Insight into the "lives" of these beads can be achieved by contextualizing the successive stages of their biographies within the environmental and social conditions of the Magdalenian.