By Sheryl Ubelacker, The Canadian Press Posted: Peter Chaban was up early doing dishes one morning in 2012 when he noticed there was water flowing over his hand — but he couldn't feel it. Next thing he knew, he lost all sensation and strength on his left side and dropped to floor. Within seconds he was lying there completely immobilized. By the time the ambulance arrived at his vacation property near Collingwood, Ont., Chaban had recovered. But doctors at the local hospital diagnosed him with a probable transient ischemic attack, or TIA, a type of temporary stroke that leaves no permanent damage. Once he returned home to Toronto, Chaban was sent for an MRI, and the brain scan confirmed that diagnosis. But of more concern was the discovery of "quite a few" lesions in his brain, the result of "silent strokes" that show up as small holes on imaging. When the strokes had occurred and over what time period was a mystery to Chaban, who had experienced no symptoms. That's why, in fact, they're known as silent — patients have no idea they've had a miniature clot or microbleed in the brain that has destroyed a tiny chunk of neurons, but resulted in no loss of function as would typically occur with a full-blown stroke. "I was never aware of any deficits," said Chaban, 64, who retired from his research job at the Hospital for Sick Children three years ago. "When I was employed, I was quite cognitively active. "I was physically very active. I ski, play golf, I played squash until a few years ago. And my health is very good, so the silent strokes hadn't expressed themselves, at least to my awareness." ©2016 CBC/Radio-Canada.

Keyword: Stroke
Link ID: 23025 - Posted: 12.27.2016

As 2016 draws to a close, we are re-visiting some of the people we met this year — including one man who survived a stroke at a young age, and a listener who heard his story on the radio. DAVID GREENE, HOST: Now as 2016 draws to a close, we're revisiting some of the people we met this year. And NPR's Rae Ellen Bichell checks back with a man who survived a stroke in his 40s and also a listener who heard his story. RAE ELLEN BICHELL, BYLINE: Back in February, I reported a story about strokes increasing in adults under 50. Troy Hodge, a 43-year-old man living in Maryland, shared his story about having a stroke two years earlier. (SOUNDBITE OF ARCHIVED BROADCAST) TROY HODGE: I remember setting myself on the floor because I was really hot. And I wanted to get some water to splash on my face. BICHELL: When the story aired on MORNING EDITION, the radio waves carried Hodge's voice into the home of Sue Bryson, a teacher in Virginia. SUE BRYSON: It was just a normal Monday morning and I was just getting ready for work and I was listening to NPR. BICHELL: Listening to Hodge's story, Bryson realized that right then, she was having similar symptoms, that she was having a stroke. So she called her neighbors and they took her to the emergency room. BRYSON: I would have never gone to the hospital if I didn't hear your show - never. BICHELL: Bryson is now back in the classroom and Hodge has made some changes. He moved into a bigger apartment. He walks up a flight of stairs each day without his cane to check the mail. He sometimes forgets things. HODGE: Memory's not too bad, I mean, it's... © 2016 npr

Keyword: Stroke
Link ID: 23024 - Posted: 12.27.2016

Anna Gorman Rosemary Navarro was living in Mexico when her brother called from California. Something wasn't right with their mom, then in her early 40s. She was having trouble paying bills and keeping jobs as a food preparer in convalescent homes. Navarro, then 22, sold her furniture to pay for a trip back to the U.S. for herself and her two young children. Almost as soon as she arrived, she knew her mother wasn't the same person. "She was there but sometimes she wasn't there," she said. "I thought, 'Oh man this isn't going to be good.' " Before long, Navarro was feeding her mom, then changing her diapers. She put a special lock on the door to keep her from straying outside. Unable to continue caring for her, Navarro eventually moved her mom to a nursing home, where she spent eight years. Near the end, her mom, a quiet woman who had immigrated to the U.S. as a teenager and loved telenovelas, could communicate only by laughing or crying. Navarro was there when she took her last breath in 2009, at age 53. "What I went through with my mom I wouldn't wish on anyone," she said. Article continues after sponsorship It has happened again and again in her family — relatives struck by the same terrible disease, most without any clue what it was. An aunt, an uncle, a cousin, a grandfather, a great grandfather. "Too many have died," Navarro said. All in their early 50s. © 2016 npr

Keyword: Alzheimers
Link ID: 23023 - Posted: 12.27.2016

By Stephen L. Macknik Masashi Atarashi, a physics high school teacher from Japan, submitted this wonderful winter illusion to the 2015 Best Illusion of the Year Contest, where it competed as a finalist. Atarashi discovered this effect serendipitously, while watching the snow fall through the venetian window blinds of his school’s faculty lounge—just like his students must sometimes do in the classroom during a lecture! Notice that as the blinds occupy more area on the screen, the speed of the snowfall seems to accelerate. A great illusion to ponder during our white holiday season. Nobody knows how Atarashi’s effect works, but our working hypothesis is that each time the snow disappears behind a blind, or reappears below it, it triggers transient increases in the activity of your visual system’s motion-sensitive neurons. Such transient surges in neural activity are perhaps misinterpreted by your brain as faster motion speed. © 2016 Scientific American,

Keyword: Vision
Link ID: 23022 - Posted: 12.27.2016

By Susana Martinez-Conde, Stephen L. Macknik We think we know what we want—but do we, really? In 2005 Lars Hall and Petter Johansson, both at Lund University in Sweden, ran an experiment that transformed how cognitive scientists think about choice. The experimental setup looked deceptively simple. A study participant and researcher faced each other across a table. The scientist offered two photographs of young women deemed equally attractive by an independent focus group. The subject then had to choose which portrait he or she found more appealing. Next, the experimenter turned both pictures over, moved them toward the subjects and asked them to pick up the photo they just chose. Subjects complied, unaware that the researcher had just performed a swap using a sleight-of-hand technique known to conjurers as black art. Because your visual neurons are built to detect and enhance contrast, it is very hard to see black on black: a magician dressed in black against a black velvet backdrop can look like a floating head. Hall and Johansson deliberately used a black tabletop in their experiment. The first photos their subjects saw all had black backs. Behind those, however, they hid a second picture of the opposite face with a red back. When the experimenter placed the first portrait face down on the table, he pushed the second photo toward the subject. When participants picked up the red-backed photos, the black-backed ones stayed hidden against the table's black surface—that is, until the experimenter could surreptitiously sweep them into his lap. © 2016 Scientific American

Keyword: Consciousness; Attention
Link ID: 23021 - Posted: 12.26.2016

By Drake Baer Convergent evolution is what happens when nature takes different courses from different starting points to arrive at similar results. Consider bats, birds, and butterflies developing wings; sharks and dolphins finding fins; and echidnas and porcupines sporting spines. Or, if you want to annoy a traditionalist scientist, talk about humans and octopuses — and how they may both have consciousness. This is the thrust of Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness, a new book by the scuba-diving, biology-specializing philosopher Peter Godfrey-Smith, originally of Australia and now a distinguished professor at the City University of New York’s graduate center. The book was written up by Olivia Judson in The Atlantic, and you should read the whole thing, but what I find mesmerizing is how categorically other the eight-tentacled ink-squirters are, and how their very nature challenges our conceptualizations of intelligence. “If we can make contact with cephalopods as sentient beings, it is not because of a shared history, not because of kinship, but because evolution built minds twice over,” Godfrey-Smith is quoted as saying. “This is probably the closest we will come to meeting an intelligent alien.” (He’s not the first to think so: The Hawaiian creation myth holds that octopuses are the only creatures left over from an earlier incarnation of the Earth, making them more proto-terrestrials than extraterrestrials.) © 2016, New York Media LLC.

Keyword: Evolution; Learning & Memory
Link ID: 23020 - Posted: 12.26.2016

By Veronique Greenwood Babies' ability to soak up language makes them the envy of adult learners everywhere. Still, some grown-ups can acquire new tongues with surprising ease. Now some studies suggest it is possible to predict a person's language-learning abilities from his or her brain structure or activity—results that may eventually be used to help even the most linguistically challenged succeed. In one study, published in 2015 in the Journal of Neurolinguistics, a team of researchers looked at the structure of neuron fibers in white matter in 22 beginning Mandarin students. Those who had more spatially aligned fibers in their right hemisphere had higher test scores after four weeks of classes, the scientists found. Like a freeway express lane, highly aligned fibers are thought to speed the transfer of information within the brain. Although language is traditionally associated with the left hemisphere, the right, which seems to be involved in pitch perception, may play a role in distinguishing the tones of Mandarin, speculates study author Zhenghan Qi of the Massachusetts Institute of Technology. Wired for Learning Your ability to learn a new language may be influenced by brain wiring. Diffusion tensor imaging of native English speakers learning Mandarin reveals that people who learn better have more aligned nerve fibers (shown with warmer colors) in two regions in the right hemisphere (A and B). In this case, subject 2, who has more aligned fibers, was a more successful learner than subject 1. © 2016 Scientific American

Keyword: Language
Link ID: 23019 - Posted: 12.26.2016

By NICHOLAS BAKALAR Using a sauna may be more than just relaxing and refreshing. It may also reduce the risk for Alzheimer’s disease and other forms of dementia, a new study suggests. Researchers in Finland analyzed medical records of 2,315 healthy men ages 42 to 60, tracking their health over an average of about 20 years. During that time, they diagnosed 204 cases of dementia and 123 cases of Alzheimer’s disease. The study, in Age and Ageing, controlled for alcohol intake, smoking, blood pressure, diabetes and other health and behavioral factors. It found that compared with men who used a sauna once a week, those who used a sauna four to seven times a week had a 66 percent lower risk for dementia and a 65 percent lower risk for Alzheimer’s disease. The senior author, Jari Antero Laukkanen, a professor of clinical medicine at the University of Eastern Finland, said that various physiological mechanisms may be involved. Sauna bathing may, for example, lead to reduced inflammation, better vascular function or lowered blood pressure. “Overall relaxation and well-being can be another reason,” he added, though the findings were only an association. “We need more studies to clarify mechanisms and confirm our findings.” © 2016 The New York Times Company

Keyword: Miscellaneous
Link ID: 23018 - Posted: 12.26.2016

Mo Costandi The rhythm of breathing co-ordinates electrical activity across a network of brain regions associated with smell, memory, and emotions, and can enhance their functioning, according to a new study by researchers at Northwestern University. The findings, published in the Journal of Neuroscience, suggest that breathing does not merely supply oxygen to the brain and body, but may also organise the activity of populations of cells within multiple brain regions to help orchestrate complex behaviours. Nearly 75 years ago, the British physiologist Edgar Adrian used electrodes to record brain activity in hedgehogs, and found that brain waves in the olfactory system were closely coupled to breathing, with their size and frequency being directly related to the speed at which air moves through the nose. Since then, this same activity has been observed in the olfactory bulb and other brain regions of rats, mice and other small animals, but until now it has not been investigated in humans. In this new study, a research team led by Christina Zelano recorded electrical activity directly from the surface of the brain in seven patients being evaluated for surgery to treat drug-resistant temporal lobe epilepsy, focusing on three brain regions: the piriform cortex, which processes smell information from the olfactory bulbs, the hippocampus, which is critical for memory formation, and the amygdala, which plays an important role in emotional processing. At the same time, they monitored the patients’ respiratory rates with either pressure sensors or an abdominal breathing belt. The researchers found that slow brain wave oscillations in the piriform cortex, and higher frequency brain waves in the hippocampus and amygdala, were synchronised with the rate of natural, spontaneous breathing. Importantly, though, the brain wave oscillations in all three regions were most highly synchronised immediately after the patients breathed in, but less so while they were breathing out. And when the patients were asked to divert breathing to their mouths, the researchers observed a significant decrease in brain wave coupling. © 2016 Guardian News and Media Limited

Keyword: Stress
Link ID: 23017 - Posted: 12.23.2016

By DANNY HAKIM LONDON — Syngenta, the Swiss pesticide giant, claims on its website that data from an influential 2011 study shows that farmers who use the weed killer paraquat are less likely to develop Parkinson’s disease than the general population. However, Syngenta’s claim is at odds with the actual findings of the study, according to two of its authors. The 2011 study, carried out by the National Institutes of Health and researchers from other institutions around the world, found that people who used paraquat or another pesticide, called rotenone, were roughly two and a half times more likely to develop Parkinson’s. The work is known as the Farming and Movement Evaluation, or FAME, study. It drew on a sweeping United States government project called the Agricultural Heath Study, which tracked more than 80,000 farmers and their spouses, as well as other people who applied pesticides, in Iowa and North Carolina. The FAME researchers identified 115 people from the Agricultural Health Study who developed Parkinson’s, and studied 110 of them who provided information on the pesticides they used. The study was influential even among some people who had been skeptics of a connection between the chemicals and the disease. Gary W. Miller, a professor of environmental health at Emory University, referred to a link between Parkinson’s and paraquat as a “red herring” in a 2007 publication. But while Dr. Miller said in a recent email exchange that he had concerns about some previous research making the connection, “the FAME data are strong and should be considered.” He said the study “appears to show a connection between paraquat exposure and Parkinson’s disease.” Because of the prominence of the FAME study, Syngenta addresses it on one of its websites, paraquat.com. Syngenta claims that the study shows that only 115 people had Parkinson’s out of the more than 80,000 people in the broader Agricultural Health Study. Therefore, “the incidence of Parkinson’s disease” in the study “appears to be lower than in the general U.S. population,” Syngenta says. © 2016 The New York Times Company

Keyword: Parkinsons; Neurotoxins
Link ID: 23016 - Posted: 12.23.2016

Sarah Boseley Health editor The NHS is to pay for 10 people to be implanted with a “bionic eye”, a pioneering technology that can restore some sight to those who have been blind for years. Only a handful of people have undergone surgery in trials so far to equip them to use Argus II, which employs a camera mounted in a pair of glasses and a tiny computer to relay signals directly to the nerves controlling sight. The decision to fund the first 10 NHS patients to be given the bionic eye could pave the way for the life-changing technology to enter the mainstream. Those who will get the equipment can currently see nothing more than the difference between daylight and darkness. The system allows the brain to decode flashes of light, so that they can learn to see movement. One of three patients to have had the implant into the retina in trials at Manchester Royal Eye hospital is Keith Hayman, 68, from Lancashire, who has five grandchildren. He was diagnosed with retinitis pigmentosa in his 20s. The disease causes cells in the retina gradually to stop working and eventually die. Hayman, who was originally a butcher, was registered blind in 1981, and forced to give up all work. “Having spent half my life in darkness, I can now tell when my grandchildren run towards me and make out lights twinkling on Christmas trees,” he said. “I would be talking to a friend, who might have walked off and I couldn’t tell and kept talking to myself. This doesn’t happen anymore, because I can tell when they have gone.” They may seem like little things, he said, but “they make all the difference to me”. © 2016 Guardian News and Media Limited

Keyword: Vision; Robotics
Link ID: 23015 - Posted: 12.23.2016

Lisa Vincenz-Donnelly A test that records the way the brain processes sound might provide a simple and reliable measure of concussion, a small study suggests. If the method works, it could help scientists work out how best to treat the poorly understood brain injury. In a paper published on 22 December in Scientific Reports1, neuroscientist Nina Kraus of Northwestern University in Evanston, Illinois, and other researchers say that they have found that a particular signal in neural activity, recorded with electrodes placed on the head as children listen to 'da' sounds from a speech synthesizer, can objectively demarcate concussed children from a healthy control group. The research was done on just 40 people — a tiny group — and will have to be repeated in larger samples. But other researchers are still excited by the report, because concussion is hard to diagnose, particularly in children. The study “may for the first time offer a simple and objective biomarker to measure the severity of brain injuries”, says Thomas Wisniewski, a neurologist at New York University’s Langone Medical Center. There is intense interest in finding a clear-cut biological signature for concussion, he says. “We have been crying out for a reliable method." Millions of people enter hospitals every year with blows to the head, and some of have concussion, a minor brain injury that can betoken more serious damage. To diagnose it, physicians rely on subjective complaints of dizziness, coordination tests and sometimes more involved procedures, such as magnetic resonance imaging (MRI) or computed tomography (CT) scans. But there’s no single objective way to detect concussion and measure its severity — and no simple test that can be administered regularly to determine when someone has recovered, a particularly important issue for athletes keen to be allowed back on the field. © 2016 Macmillan Publishers Limited

Keyword: Brain Injury/Concussion; Hearing
Link ID: 23014 - Posted: 12.23.2016

By James Gallagher Health and science reporter, BBC News website A drug that alters the immune system has been described as "big news" and a "landmark" in treating multiple sclerosis, doctors and charities say. Trials, published in the New England Journal of Medicine, suggest the drug can slow damage to the brain in two forms of MS. Ocrelizumab is the first drug shown to work in the primary progressive form of the disease. The drug is being reviewed for use in the US and Europe. MS is caused by a rogue immune system mistaking part of the brain for a hostile invader and attacking it. It destroys the protective coating that wraps round nerves called the myelin sheath. The sheath also acts like wire insulation to help electrical signals travel down the nerve. Damage to the sheath prevents nerves from working correctly and means messages struggle to get from the brain to the body. This leads to symptoms like having difficulty walking, fatigue and blurred vision. The disease can either just get worse, known as primary progressive MS, or come in waves of disease and recovery, known as relapsing remitting MS. Both are incurable, although there are treatments for the second state. 'Change treatment' Ocrelizumab kills a part of the immune system - called B cells - which are involved in the assault on the myelin sheath. In 732 patients with progressive MS, the percentage of patients that had deteriorated fell from 39% without treatment to 33% with ocrelizumab . Patients taking the drug also scored better on the time needed to walk 25 feet and had less brain loss detected on scans. In 1,656 patients with relapsing remitting, the relapse rate with ocrelizumab was half that of using another drug. © 2016 BBC

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 23013 - Posted: 12.23.2016

Jon Hamilton For patients with serious brain injuries, there's a strong link between sleep patterns and recovery. A study of 30 patients hospitalized for moderate to severe traumatic brain injuries found that sleep quality and brain function improved in tandem, researchers reported Wednesday in the journal Neurology. Patients who still had low levels of consciousness and cognitive functioning would "sleep for a couple of minutes and then wake up for a couple of minutes," both day and night, says Nadia Gosselin, the study's senior author and an assistant professor in the psychology department at the University of Montreal. But "when the brain recovered, the [normal] sleep-wake cycle reappeared," Gosselin says. The results raise the possibility that patients with brain injuries might recover more quickly if hospitals took steps to restore normal sleep patterns, Gosselin says. Drugs are one option, she says. Another is making sure patients are exposed to sunlight or its equivalent during the day and at night rest in a dark, quiet environment. "I think bad sleep can have bad consequences for brain recovery," she says. The findings are consistent with other research showing that "sleep is essential to restore body and brain functions," according to an editorial accompanying the study. The editorial was written by Andrea Soddu of the University of Western Ontario, and Claudio Bassetti of University Hospital Inselspital Bern in Switzerland. © 2016 npr

Keyword: Sleep; Brain Injury/Concussion
Link ID: 23012 - Posted: 12.23.2016

By STEPH YIN Inuit who live in Greenland experience average temperatures below freezing for at least half of the year. For those who live in the north, subzero temperatures are normal during the coldest months. Given these frigid conditions, anthropologists have wondered for decades whether the Inuit in Greenland and other parts of the Arctic have unique biological adaptations that help them tolerate the extreme cold. A new study, published on Wednesday in Molecular Biology and Evolution, identifies gene variants in Inuit who live in Greenland, which may help them adapt to the cold by promoting heat-generating body fat. These variants possibly originated in the Denisovans, a group of archaic humans who, along with Neanderthals, diverged from modern humans about half a million years ago. “As modern humans spread around the world, they interbred with Denisovans and Neanderthals, who had already been living in these different environments for hundreds of thousands of years,” said Rasmus Nielsen, a professor of integrative biology at the University of California, Berkeley and an author of the paper. “This gene exchange may have helped some modern humans adapt to and conquer new environments.” The new study follows earlier research by Dr. Nielsen and colleagues, which found genetic mutations that might help the Inuit metabolize unsaturated fatty acids common in their diet of whales, seals and fish. In this study, Dr. Nielsen’s team focused on another distinct region in the Inuit genome, which seems to affect body fat distribution and other aspects of development. The researchers compared the genomes of nearly 200 Inuit with genomes of Neanderthals, Denisovans and modern populations around the world. © 2016 The New York Times Company

Keyword: Evolution
Link ID: 23011 - Posted: 12.23.2016

By Laurence O’Dwyer Daniel Tammet correctly recited the first 22,514 digits of Pi over the course of five hours and nine minutes. Less well-known, but similarly impressive, is the ability of a Clark’s nutcracker (Nucifraga columbiana)—a bird commonly found along the western flanks of North America—to remember where it stores thousands of separate caches of food. Tammet, who has autism spectrum disorder, is a savant. Some researchers have proposed that Clark’s nutcrackers might also represent a type of autistic savant. However, the unique abilities of a person with an autism spectrum disorder and savant syndrome usually comes at the price of social deficits. Experts in animal cognition who have examined similar abilities in birds and other creatures maintain that nonhuman animals that exhibit savant-like behavior do not display any equivalent dysfunction. The prodigious memory of the Clark’s nutcracker seems to be accompanied by an enlarged hippocampus compared with related species of birds that have not developed caching abilities, but in all other respects the bird seems to function normally. The hippocampus is a brain structure that is crucial for memory formation. In other words, its hyper-performance in one domain does not appear to come at a cost in another. (Admittedly, it is difficult to determine whether Clark’s nutcrackers are socially competent birds.) The “gift at a price” idea stems in part from the left hemisphere dysfunction and right hemisphere compensation that is often associated with savant syndrome. © 1986-2016 The Scientist

Keyword: Autism; Learning & Memory
Link ID: 23010 - Posted: 12.23.2016

Ramin Skibba The high-pitched squeals of the humble bat may be as complex as the calls of dolphins and monkeys, researchers have found. A study published on 22 December in Scientific Reports1 reveals that the fruit bat is one of only a few animals known to direct its calls at specific individuals in a colony, and suggests that information in the calls of many social animals may be more detailed than was previously thought. Bats are noisy creatures, especially in their crowded caves, where they make calls to their neighbours. “If you go into a fruit-bat cave, you hear a cacophony,” says Yossi Yovel, a neuroecologist at Tel Aviv University in Israel who led the study. Until now, it has been difficult to separate this noise into distinct sounds, or to determine what prompted the individual to make a particular call. “Animals make sounds for a reason,” says Whitlow Au, a marine-bioacoustics scientist at the University of Hawaii at Manoa. “Most of the time, we don’t quite understand those reasons.” To find out what bats are talking about, Yovel and his colleagues monitored 22 captive Egyptian fruit bats (Rousettus aegyptiacus) around the clock for 75 days. They modified a voice-recognition program to analyse approximately 15,000 vocalizations collected during this time. The program was able to tie specific sounds to different social interactions captured by video, such as when two bats fought over food. © 2016 Macmillan Publishers

Keyword: Language; Animal Communication
Link ID: 23009 - Posted: 12.23.2016

Carl Zimmer Leah H. Somerville, a Harvard neuroscientist, sometimes finds herself in front of an audience of judges. They come to hear her speak about how the brain develops. It’s a subject on which many legal questions depend. How old does someone have to be to be sentenced to death? When should someone get to vote? Can an 18-year-old give informed consent? Scientists like Dr. Somerville have learned a great deal in recent years. But the complex picture that’s emerging lacks the bright lines that policy makers would like. “Oftentimes, the very first question I get at the end of a presentation is, ‘O.K., that’s all very nice, but when is the brain finished? When is it done developing?’” Dr. Somerville said. “And I give a very nonsatisfying answer.” Dr. Somerville laid out the conundrum in detail in a commentary published on Wednesday in the journal Neuron. The human brain reaches its adult volume by age 10, but the neurons that make it up continue to change for years after that. The connections between neighboring neurons get pruned back, as new links emerge between more widely separated areas of the brain. Eventually this reshaping slows, a sign that the brain is maturing. But it happens at different rates in different parts of the brain. The pruning in the occipital lobe, at the back of the brain, tapers off by age 20. In the frontal lobe, in the front of the brain, new links are still forming at age 30, if not beyond. “It challenges the notion of what ‘done’ really means,” Dr. Somerville said. As the anatomy of the brain changes, its activity changes as well. In a child’s brain, neighboring regions tend to work together. By adulthood, distant regions start acting in concert. Neuroscientists have speculated that this long-distance harmony lets the adult brain work more efficiently and process more information. © 2016 The New York Times Company

Keyword: Development of the Brain
Link ID: 23008 - Posted: 12.22.2016

By Kelly Servick The “mad cow disease” epidemic that killed more than 200 people in Europe peaked more than a decade ago, but the threat it poses is still real. Eating meat contaminated with bovine spongiform encephalopathy and its hallmark misshapen proteins, called prions, can cause a fatal and untreatable brain disorder, variant Creutzfeldt-Jakob disease (vCJD). Thousands of Europeans are thought to be asymptomatic carriers, and they can spread prions through blood donations. So for years, researchers have sought a test to safeguard blood supplies. This week, two teams bring that goal closer. They describe methods for detecting prions in blood that proved highly accurate in small numbers of samples from infected people and controls. “There is new technology to go forward, and it looks promising,” says Jonathan Wadsworth, a biochemist who studies prion disease at University College London. “These are definitely very welcome papers.” Analyses of discarded appendix and tonsil samples suggest that as many as one in 2000 people in the United Kingdom carries abnormal prions—misfolded variations of a naturally abundant protein, which prompt surrounding healthy proteins to fold and clump abnormally. No one knows how many of these carriers will ever develop vCJD; incubation periods as long as 50 years have been reported. Once symptoms occur—first depression and hallucinations, and eventually dementia and loss of motor control—patients survive about a year. Four people are known to have contracted vCJD through a blood transfusion from an infected donor. © 2016 American Association for the Advancement of Science.

Keyword: Prions
Link ID: 23007 - Posted: 12.22.2016

Rachel Ehrenberg Scientists investigating what keeps lungs from overinflating can quit holding their breath. Experiments in mice have identified a protein that senses when the lungs are full of air. This protein helps regulate breathing in adult mice and gets breathing going in newborn mice, researchers report online December 21 in Nature. If the protein plays a similar role in people — and a few studies suggest that it does — exploring its activity could help explain disorders such as sleep apnea or chronic obstructive pulmonary disease. “These are extremely well done, very elegant studies,” says neonatologist Shabih Hasan of the University of Calgary in Canada, a specialist in breathing disorders in newborns. Researchers knew that feedback between the lungs and brain maintains normal breathing. But “this research give us an understanding at the cellular level,” says Hasan. “It’s a major advance.” Called Piezo2, the protein forms channels in the membranes of nerve cells in the lungs. When the lungs stretch, the Piezo2 channels detect the distortion caused by the mechanical force of breathing and spring open, triggering the nerves to send a signal. Led by neuroscientist Ardem Patapoutian, researchers discovered that the channels send signals along three different pathways. Mice bred to lack Piezo2 in a cluster of nerve cells that send messages to the spinal cord had trouble breathing and died within 24 hours. Similarly, newborn mice missing Piezo2 channels in nerves that communicate with the brain stem via a structure called the jugular ganglion also died. |© Society for Science & the Public 2000 - 2016.

Keyword: Pain & Touch
Link ID: 23006 - Posted: 12.22.2016