Chapter 16. None

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By Diana Kwon In people who suffer from pain disorders, painful feelings can severely worsen and spread to other regions of the body. Patients who develop chronic pain after surgery, for example, will often feel it coming from the area surrounding the initial injury and even in some parts of the body far from where it originates. New evidence suggests glia, non-neuronal cells in the brain, may be the culprits behind this effect. Glia were once thought to simply be passive, supporting cells for neurons. But scientists now know they are involved in everything from metabolism to neurodegeneration. A growing body of evidence points to their key role in pain. In a study published today in Science, researchers at the Medical University of Vienna report that glia are involved in long-term potentiation (LTP), or the strengthening of synapses, in pain pathways in the spinal cord. Neuroscientists Timothy Bliss and Terje Lømo first described LTP in the hippocampus, a brain area involved in memory, in the 1970s. Since then scientists have been meticulously studying the role this type of synaptic plasticity—the ability of synapses to change in strength—plays in learning and memory. More recently, researchers discovered that LTP could also amplify pain in areas where injuries or inflammation occur. “We sometimes call this a ‘memory trace of pain’ because the painful insult may lead to subsequent hypersensitivity to painful stimuli, and it was clear that synaptic plasticity can play a role here,” says study co-author Jürgen Sandkühler, a neuroscientist also at the Medical University of Vienna. But current models of how LTP works could not explain why discomfort sometimes becomes widespread or experienced in areas a person has never felt it before, he adds. © 2016 Scientific American

Keyword: Pain & Touch; Glia
Link ID: 22857 - Posted: 11.12.2016

by Helen Thompson Narwhals use highly targeted beams of sound to scan their environment for threats and food. In fact, the so-called unicorns of the sea (for their iconic head tusks) may produce the most refined sonar of any living animal. A team of researchers set up 16 underwater microphones to eavesdrop on narwhal click vocalizations at 11 ice pack sites in Greenland’s Baffin Bay in 2013. The recordings show that narwhal clicks are extremely intense and directional — meaning they can widen and narrow the beam of sound to find prey over long and short distances. It’s the most directional sonar signal measured in a living species, the researchers report November 9 in PLOS ONE. The sound beams are also asymmetrically narrow on top. That minimizes clutter from echoes bouncing off the sea surface or ice pack. Finally, narwhals scan vertically as they dive, which could help them find patches of open water where they can surface and breathe amid sea ice cover. All this means that narwhals employ pretty sophisticated sonar. The audio data could help researchers tell the difference between narwhal vocalizations and those of neighboring beluga whales. It also provides a baseline for assessing the potential impact of noise pollution from increases in shipping traffic made possible by sea ice loss. |© Society for Science & the Public 2000 - 2016.

Keyword: Hearing
Link ID: 22856 - Posted: 11.12.2016

By John Bohannon When it comes to influential neuroscience research, University College London (UCL) has a lot to boast about. That's not the opinion of a human but rather the output of a computer program that has now parsed the content of 2.5 million neuroscience articles, mapped all of the citations between them, and calculated a score of each author's influence on the rest. Three of the top 10 most influential (see table below) neuroscientists hail from UCL: Karl Friston (1st), Raymond Dolan (2nd), and Chris Frith (7th). The secret of their success? "We got into human functional brain imaging very early," Frith says. Getting in early made it possible to "be first to do many of the obvious studies." The program, called Semantic Scholar, is an online tool built at the Allen Institute for Artificial Intelligence (AI2) in Seattle, Washington. When it debuted in April, it calculated the most influential computer scientists based on 2 million papers from that field. Since then, the AI2 team has expanded the corpus to 10 million papers, 25% of which are from neuroscience. They hope to expand that to all of the biomedical literature next year, over 20 million papers. When Semantic Scholar looks at a paper published online, what does it actually see? Much more than the typical academic search engine, says Oren Etzioni, CEO of AI2 who has led the project. "We are using machine learning, natural language processing, and [machine] vision to begin to delve into the semantics." © 2016 American Association for the Advancement of Science

Keyword: Miscellaneous
Link ID: 22855 - Posted: 11.12.2016

Ian Sample Science editor Partially-paralysed monkeys have learned to walk again with a brain implant that uses wireless signals to bypass broken nerves in the spinal cord and reanimate the useless limbs. The implant is the first to restore walking ability in paralysed primates and raises the prospect of radical new therapies for people with devastating spinal injuries. Scientists hope the technology will help people who have lost the use of their legs, by sending movement signals from their brains to electrodes in the spine that activate the leg muscles. One rhesus macaque that was fitted with the new implant regained the ability to walk only six days after it was partially paralysed in a surgical procedure that severed some of the nerves that controlled its right hind leg. “It was a big surprise for us,” said Grégoire Courtine, a neuroscientist who led the research at the Swiss Federal Institute of Technology. “The gait was not perfect, but it was almost like normal walking. The foot was not dragging and it was fully weight bearing.” A second animal in the study that received more serious damage to the nerves controlling its right hind leg recovered the ability to walk two weeks after having the device fitted, according to a report published in the journal, Nature. Both monkeys regained full mobility in three months. The “brain-spine interface” is the latest breakthrough to come from the rapidly-advancing area of neuroprosthetics. Scientists in the field aim to read intentions in the brain’s activity and use it to control computers, robotic arms and even paralysed limbs. © 2016 Guardian News and Media Limited

Keyword: Movement Disorders; Robotics
Link ID: 22854 - Posted: 11.10.2016

Geoff Brumfiel Scientists have pinpointed the ticklish bit of a rat's brain. The results, published in the journal Science, are another step toward understanding the origins of ticklishness, and its purpose in social animals. Although virtually every human being on the planet has been tickled, scientists really don't understand why people are ticklish. The idea that a certain kind of touching could easily lead to laughter is confusing to a neuroscientist, says Shimpei Ishiyama, a postdoc at the Berstein Center for Computational Nueroscience in Berlin, Germany. "Just a physical touch inducing such an emotional output — this is very mysterious," Ishiyama says. "This is weird." To try and get a handle on how tickling works, Ishiyama studied rats, who seem to enjoy being tickled, according to previous research. He inserted electrodes into the rats' brains, in a region called their somatosensory cortex. When rats enjoy tickling they emit high-pitched "laughter" that can't normally be heard by humans, the scientists found. In this video, the researchers transposed the audio of the squeaks to a lower frequency you can hear. That's a part of the brain that processes touch, and when Ishiyama tickled the rats, it caused neurons in that region to fire. The rats also seemed to giggle hysterically, emitting rapid-fire, ultrasonic squeaks. Earlier research has shown rats naturally emit those squeaks during frisky social interaction, such as when they are playing with other rats. © 2016 npr

Keyword: Emotions; Evolution
Link ID: 22853 - Posted: 11.10.2016

By Alison F. Takemura In the 1980s, neuroscientists were facing an imaging problem. They had developed a new way to detect neuronal activity with calcium dyes, but visualizing the markers proved challenging. The dyes fluoresced in the presence of calcium ions when illuminated with ultraviolet (UV) light, but it was difficult to build UV lenses for confocal microscopes—instruments that allowed scientists to peer hundreds of micrometers deep into the brain. To make matters worse, because biological tissue scatters light so effectively, confocal scopes required excessive light intensities, which caused irreparable damage to samples. “You basically burned your tissue,” says Winfried Denk, director of the Max Planck Institute of Neurobiology in Martinsried, Germany. The time was ripe for a gentler option, and Denk developed two-photon excitation microscopy in 1990. Instead of using a single photon to excite a calcium dye, scientists could use two photons and half the illumination energy—red or infrared lasers, instead of ultraviolet. The scatter of such low-energy rays caused far less damage to surrounding tissue. The technology had another advantage. To excite a molecule, both photons had to reach it simultaneously. This meant the laser could only excite a tiny patch of tissue where its photons were most concentrated, giving scientists a new level of precision. © 1986-2016 The Scientist

Keyword: Brain imaging
Link ID: 22852 - Posted: 11.10.2016

By Anna Azvolinsky In January 1983, 22-year-old Amita Sehgal arrived in New York City from India to visit her oldest sister, who was due to have a baby. Sehgal had just been rejected from the molecular biology PhD programs at Rockefeller University and Columbia University. “I felt that I had no prospects,” says the University of Pennsylvania professor of neuroscience. She had heard about a Cornell University in NYC, so she and her other sister walked the streets of Manhattan asking its whereabouts. “Someone told us Cornell was hundreds of miles away in Ithaca, and that I must have been asking about the medical school. I had no idea, but I said ‘Yes’ and was directed to the Upper East Side.” Sehgal walked into the medical school, inquired about their PhD program, and was told that the application deadline for the program was that very day. “I sat in the office and filled out the application, wrote my essay, and handed it in!” she says. A few months later, Sehgal was admitted into the genetics program. Sehgal’s parents had also joined the visit and were returning to India in July, shortly before she started the PhD program. “It was fortuitous the way things worked out. My parents were comfortable leaving me in New York because my oldest sister was living there.” One month later, however, her sister and family moved to Florida, and Sehgal was alone, living in Cornell housing. “The first six months were really, really rough,” she says. Cornell had dissolved the genetics program to which Sehgal had been admitted and offered her tuition support with no stipend—and that only for the first semester. “My parents and sister were in no position to help me financially,” she says. Sehgal found a professor at the adjacent Memorial Sloan Kettering Cancer Center (MSKCC), Raju Chaganti, who gave her part-time work with no expectation that she join his lab. She had little money and survived on ramen noodles. © 1986-2016 The Scientist

Keyword: Sleep
Link ID: 22850 - Posted: 11.10.2016

By LESLEY ALDERMAN Take a deep breath, expanding your belly. Pause. Exhale slowly to the count of five. Repeat four times. Congratulations. You’ve just calmed your nervous system. Controlled breathing, like what you just practiced, has been shown to reduce stress, increase alertness and boost your immune system. For centuries yogis have used breath control, or pranayama, to promote concentration and improve vitality. Buddha advocated breath-meditation as a way to reach enlightenment. Science is just beginning to provide evidence that the benefits of this ancient practice are real. Studies have found, for example, that breathing practices can help reduce symptoms associated with anxiety, insomnia, post-traumatic stress disorder, depression and attention deficit disorder. “Breathing is massively practical,” says Belisa Vranich, a psychologist and author of the book “Breathe,” to be published in December. “It’s meditation for people who can’t meditate.” How controlled breathing may promote healing remains a source of scientific study. One theory is that controlled breathing can change the response of the body’s autonomic nervous system, which controls unconscious processes such as heart rate and digestion as well as the body’s stress response, says Dr. Richard Brown, an associate clinical professor of psychiatry at Columbia University and co-author of “The Healing Power of the Breath.” Consciously changing the way you breathe appears to send a signal to the brain to adjust the parasympathetic branch of the nervous system, which can slow heart rate and digestion and promote feelings of calm as well as the sympathetic system, which controls the release of stress hormones like cortisol. © 2016 The New York Times Company

Keyword: Stress
Link ID: 22849 - Posted: 11.09.2016

Elie Dolgin There are not a lot of things that could bring together people as far apart on the US political spectrum as Republican Newt Gingrich and Democrat Bob Kerrey. But in 2007, after leading a three-year commission that looked into the costs of care for elderly people, the political rivals came to full agreement on a common enemy: dementia. At the time, there were fewer than 30 million people worldwide diagnosed with the condition, but it was clear that the numbers were set to explode. By 2050, current predictions suggest, it could reach more than 130 million, at which point the cost to US health care alone from diseases such as Alzheimer’s will probably hit US$1 trillion per year in today’s dollars. “We looked at each other and said, ‘You know, if we don’t get a grip on Alzheimer’s, we can’t get anything done because it’s going to drown the system,’” recalls Gingrich, the former speaker of the US House of Representatives. He still feels that sense of urgency, and for good reason. Funding has not kept pace with the scale of the problem; targets for treatments are thin on the ground and poorly understood; and more than 200 clinical trials for Alzheimer’s therapies have been terminated because the treatments were ineffective. Of the few treatments available, none addresses the underlying disease process. “We’re faced with a tsunami and we’re trying to deal with it with a bucket,” says Gingrich. But this message has begun to reverberate around the world, which gives hope to the clinicians and scientists. Experts say that the coming wave can be calmed with the help of just three things: more money for research, better diagnostics and drugs, and a victory — however small — that would boost morale. © 2016 Macmillan Publishers Limited

Keyword: Alzheimers
Link ID: 22848 - Posted: 11.09.2016

Nancy Shute Erik Vance didn't go to a doctor until he was 18; he grew up in California in a family that practiced Christian Science. "For the first half of my life, I never questioned the power of God to heal me," Vance writes in his new book, Suggestible You: Placebos, False Memories, Hypnosis, and the Power of Your Astonishing Brain. As a young man, Vance left the faith behind, but as he became a science journalist he didn't stop thinking about how people's beliefs and expectations affect their health, whether it's with placebo pills, mystical practices or treatments like acupuncture. The answer, he found, is in our brains. Erik and I chatted about the book while attending a recent meeting of the National Association of Science Writers. Here are highlights of our conversation, edited for length and clarity. You point out that even though most of us didn't grow up Christian Scientist, we often use belief to manage our health. I've learned from writing this book that there are a lot of people around the world who really rely on expectation and placebos. And I grew up in the most extreme possible group, but it's not that different from seeing a homeopath. You're using faith to manage your body; what a psychologist would call expectation. Having had that experience really prepared me to ask some of these questions. How would your mom take care of you when you were sick? As a kid we might have 7UP with orange juice; we might go that far because it made you feel better. But the treatment was to call a practitioner, to call a healer. © 2016 npr

Keyword: Pain & Touch
Link ID: 22847 - Posted: 11.09.2016

Sara Reardon Major brain-mapping projects have multiplied in recent years, as neuroscientists develop new technologies to decipher how the brain works. These initiatives focus on understanding the brain, but the World Health Organization (WHO) wants to ensure that they work to translate their early discoveries and technological advances into tests and treatments for brain disorders. “We think there are side branches from projects that could be pursued with a very small investment to benefit public health,” says Shekhar Saxena, director of the WHO’s mental-health and substance-abuse department. Saxena will make that case on 12 November at the annual meeting of the Society for Neuroscience in San Diego, California — continuing a discussion that began in July at the WHO’s headquarters in Geneva, Switzerland. Among the roughly 70 people who attended that first meeting were leaders of the major brain initiatives, including the US BRAIN (Brain Research through Advancing Innovative Neurotechnologies) Initiative, launched in 2013; the European Human Brain Project, started in 2013; and the Japanese Brain/MINDS project, launched in 2014. All of these projects focus on basic research on the brain or the development of sophisticated tools to study it. Clinical applications are an ultimate, rather than an immediate, goal. But at the Geneva meeting, project leaders agreed, in principle, that they should do more to adapt brain-imaging technologies for use in clinical diagnoses. “The WHO is concerned that the emphasis on building these very expensive devices could worsen the health disparities that we have now between the developed and underdeveloped world,” says Walter Koroshetz, director of the US National Institute of Neurological Disorders and Stroke, which is part of the BRAIN Initiative. © 2016 Macmillan Publishers Limited

Keyword: Brain imaging
Link ID: 22846 - Posted: 11.09.2016

By STEPH YIN Neanderthals and modern humans diverged from a common ancestor about half a million years ago. Living in colder climes in Eurasia, Neanderthals evolved barrel chests, large skulls and strong hands. In Africa, modern humans acquired shorter faces, a prominent chin and slender limbs. Then, roughly 50,000 years ago, the two species encountered one another and interbred, as modern humans spread out of Africa. The legacy of this interbreeding has been the subject of much scientific inquiry in the past few years. Today, up to 4 percent of the genes of non-Africans are Neanderthal in origin.. These may have influenced a diverse range of traits, including keratin production, disease risk and the propensity to sneeze after eating dark chocolate. Where did all the other Neanderthal DNA go? Why did a Neanderthal-human hybrid not prevail? Two recent studies converge on an explanation. They suggest the answer comes down to different population sizes between Neanderthals and modern humans, and this principle of population genetics: In small populations, natural selection is less effective. “Neanderthals have this small population over hundreds of thousands of years, presumably because they’re living in very rough conditions,” said Graham Coop, a genetics professor at the University of California, Davis, and an author of one of the studies, published Tuesday in PLOS Genetics. As a result, Neanderthals were more inbred than modern humans and accumulated more mutations that have a slightly adverse effect, such as increasing one’s risk of disease, but do not prevent one from reproducing (and thus, passing such mutations along). © 2016 The New York Times Company

Keyword: Evolution; Genes & Behavior
Link ID: 22845 - Posted: 11.09.2016

By Felicity Muth Kirsty Graham is a PhD student at the University of St Andrews, Scotland, who works on gestural communication of chimpanzees and bonobos in Uganda and DRCongo. I recently asked her some questions about the work that she does and some exciting recent findings of hers about how these animals communicate. How did you become interested in communication, and specifically gestures? Languages are fascinating – the diversity, the culture, the learning – and during undergrad, I became interested in the origins of our language ability. I went to Quest University Canada (a small liberal arts university) and learned that I could combine my love of languages and animals and being outdoors! Other great apes don’t have language in the way that humans do, but studying different aspects of communication, such as gestures, may reveal how language evolved. Although my interest really started from an interest in languages, once you get so deep into studying other species you become excited about their behaviour for its own sake. In the long run, it would be nice to piece together how language evolved, but for now I’m starting with a very small piece of the puzzle – bonobo gestures. How do you study gestures in non-human primates? There are a few different approaches to studying gestures: in the wild or in captivity; through observation or with experiments; studying one gesture in detail or looking at the whole repertoire. I chose to observe wild bonobos and look at their whole repertoire. Since not much is known about bonobo gestural communication, this seemed like a good starting point. During my PhD, I spent 12 months at Wamba (Kyoto University’s research site) in the DRCongo. I filmed the bonobos, anticipating the beginning of social interactions so that I could record the gestures that they use. Then I spent a long time watching the videos, finding gestures, and coding information about the gestures. © 2016 Scientific American

Keyword: Language; Evolution
Link ID: 22840 - Posted: 11.07.2016

By Neuroskeptic A new paper could prompt a rethink of a basic tenet of neuroscience. It is widely believed that the motor cortex, a region of the cerebral cortex, is responsible for producing movements, by sending instructions to other brain regions and ultimately to the spinal cord. But according to neuroscientists Christian Laut Ebbesen and colleagues, the truth may be the opposite: the motor cortex may equally well suppress movements. Ebbesen et al. studied the vibrissa motor cortex (VMC) of the rat, an area which is known to be involved in the movement of the whiskers. First, they determined that neurons within the VMC are more active during periods when the rat’s whiskers are resting: for instance, like this: whiskerThe existence of cells whose firing negatively correlates with movement is interesting, but by itself it doesn’t prove that much. Maybe those cells are just doing something else than controlling movement? However, Ebbesen et al. went on to show that electrical stimulation of the VMC caused whiskers to stop moving, while applying a drug (lidocaine) to suppress VMC activity caused the rat’s whiskers to whisk harder. Ebbesen et al. go on to say that the inhibitory role of VMC may extend to other regions of the rat motor cortex, and to other movements beyond the whiskers: Rats can perform long sequences of skilled, learned motor behaviors after motor cortex ablation, but motor cortex is required for them to learn a task of behavioral inhibition (they must learn to postpone lever presses)35. When swimming, intact rats hold their forelimbs still and swim with only their hindlimbs. After forelimb motor cortex lesions, however, rats swim with their forelimbs also36.

Keyword: Movement Disorders
Link ID: 22837 - Posted: 11.07.2016

By Solomon Israel, A May-December romance brings benefits for young female gray jays mated to older males, according to new Canadian research. The paper, published this month in the journal Animal Behaviour, used almost four decades of data on a marked population of gray jays in Ontario's Algonquin Park to study how the birds adjust their reproductive habits in response to changes in temperature and other conditions. Gray jays, also known as Canada jays or whisky jacks, don't migrate south in the winter, instead living year-round in boreal forests across Canada and the northern U.S. They manage this feat of survival by caching food all over their large, permanent habitats, then retrieving it during the winter months. The small, fluffy birds take advantage of those winter supplies to nest much earlier than most other birds, laying eggs between late February and March. Gray jays don't migrate during the winter, instead relying on hidden caches of food to feed themselves and their offspring. (Dan Strickland) The researchers found that female gray jays that laid their eggs earlier in the season had the most reproductive success, with a higher survival rate for offspring. ©2016 CBC/Radio-Canada

Keyword: Sexual Behavior; Evolution
Link ID: 22836 - Posted: 11.07.2016

By CLAIRE CAIN MILLER and AARON E. CARROLL New parents get a lot of advice. It comes from breast-feeding “lactivists” and Ferberizers, attachment parents and anti-helicopter ones. It’s not enough to keep babies fed, rested and changed — they also need to learn grit and sign language. So when the American Academy of Pediatrics recently issued new infant sleep guidelines — highlighting a recommendation that babies sleep in their parents’ rooms for at least six months but ideally a full year — some parents despaired. The academy said that sharing a room could cut babies’ chance of dying in their sleep by “up to 50 percent.” Suffocation, strangulation or sudden infant death syndrome, known as SIDS, kills 3,500 babies a year in this country. The academy’s previous recommendations — place babies on their backs to sleep, without loose bedding, in their own cribs — have been an undisputed success in helping to cut SIDS deaths by 53 percent from 1992 to 2001, but SIDS is still the largest cause of infant mortality in the United States after the first month of life. Yet the recommendation drew skepticism from some doctors, who argued that a close look at the evidence showed that the benefits of room-sharing didn’t always justify its costs to parents, who would have to sacrifice privacy, sex and, above all, sleep. Sharing a room can make breast-feeding and bonding easier. It has historically been common around the world, and many parents do it by choice or necessity. But the evidence is not conclusive, and doctors need to understand the trade-offs before demanding that parents follow the recommendation. Doing so will be part of making parenthood possible in a society in which most parents work, yet receive less government support than in any other industrialized country. © 2016 The New York Times Company

Keyword: Sleep
Link ID: 22834 - Posted: 11.05.2016

By Greg Miller In the mid-19th century, some European doctors became fascinated with a plant-derived drug recently imported from India. Cannabis had been used as medicine for millennia in Asia, and physicians were keen to try it with their patients. No less an authority than Sir John Russell Reynolds, the house physician to Queen Victoria and later president of the Royal College of Physicians in London, extolled the medical virtues of cannabis in The Lancet in 1890. “In almost all painful maladies I have found Indian hemp by far the most useful of drugs,” Reynolds wrote. Like other doctors of his day, Reynolds thought cannabis might help reduce the need for opium-based painkillers, with their potential for abuse and overdose. “The bane of many opiates and sedatives is this, that the relief of the moment, the hour, or the day, is purchased at the expense of to-morrow’s misery,” he wrote. “In no one case to which I have administered Indian hemp, have I witnessed any such results.” More than 125 years later, the misery caused by opioids is clearer than ever, and there are new hints that cannabis could be a viable alternative. Some clinical studies suggest that the plant may have medical value, especially for difficult-to-treat pain conditions. The liberalization of marijuana laws in the United States has also allowed researchers to compare overdoses from painkiller prescriptions and opioids in states that permit medical marijuana versus those that don’t. Yet following up on those hints isn’t easy. Clinical studies face additional hurdles because the plant is listed on Schedule I, the U.S. Drug Enforcement Administration’s (DEA’s) list of the most dangerous drugs. © 2016 American Association for the Advancement of Science.

Keyword: Drug Abuse
Link ID: 22832 - Posted: 11.04.2016

Ramin Skibba A large, multi-lab replication study has found no evidence to validate one of psychology’s textbook findings: the idea that people find cartoons funnier if they are surreptitiously induced to smile. But an author of the original report — published nearly three decades ago — says that the new analysis has shortcomings, and may not represent a direct replication of his work. In 1988, Fritz Strack, a psychologist now at the University of Würzburg, Germany, and colleagues found that people who held a pen between their teeth, which induces a smile, rated cartoons as funnier than did those who held a pen between their lips, which induced a pout, or frown1. Strack chose cartoons from Gary Larson's classic 1980s series, The Far Side. Strack’s study has been quoted as a classic demonstration of what’s known as the ‘facial feedback hypothesis’ — the idea that facial expressions can influence a person’s own emotional state. The paper has been cited more than a thousand times, and has been followed by other research into facial feedback. In 2011, for example, researchers reported that injections of Botox, which affects the muscles of facial expression, dampen emotional responses2. But as part of a growing trend to reproduce famous psychology findings, a group of scientists revisited the experiment. They describe the collective results of 17 experiments, with a total of nearly 1,900 participants, in a paper published on 26 October in the journal Perspectives on Psychological Science3. © 2016 Macmillan Publishers Limited,

Keyword: Emotions
Link ID: 22831 - Posted: 11.04.2016

By Dan Hurley The Centers for Disease Control and Prevention has confirmed 89 cases of the paralyzing disease in the United States through September. A 6-year-old boy suspected of having AFM died in Seattle on Sunday, the first death believed to be caused by the disease. One of the drugs in development, pocapavir, was used briefly on a few patients during a 2014 outbreak of AFM under a compassionate-use exception that allows extremely sick patients to be given unapproved drugs without the usual kinds of placebo-controlled trials required by the Food and Drug Administration. “There were a couple of kids who got pocapavir in the Colorado outbreaks,” said Benjamin Greenberg, a neurologist who has treated children with AFM at the University of Texas Southwestern in Dallas. “It had relatively weak but measurable impact on viral replication. A larger study would definitely be warranted. We'll take anything we can get.” Although the CDC says no cause has been conclusively linked to AFM, many researchers suspect a family of viruses known as enteroviruses. “I have been studying enteroviruses for 40 years now,” said John Modlin, deputy director of the polio eradication program at the Bill and Melinda Gates Foundation. “If I had a child with acute flaccid myelitis, I would be on the phone in a second to the companies making these drugs.” © 1996-2016 The Washington Post

Keyword: Movement Disorders
Link ID: 22830 - Posted: 11.04.2016

By Kelly Servick Mark Hutchinson could read the anguish on the participants’ faces in seconds. As a graduate student at the University of Adelaide in Australia in the late 1990s, he helped with studies in which people taking methadone to treat opioid addiction tested their pain tolerance by dunking a forearm in ice water. Healthy controls typically managed to stand the cold for roughly a minute. Hutchinson himself, “the young, cocky, Aussie bloke chucking my arm in the water,” lasted more than 2 minutes. But the methadone patients averaged only about 15 seconds. “These aren’t wimps. These people are injecting all sorts of crazy crap into their arms. … But they were finding this excruciating,” Hutchinson says. “It just fascinated me.” The participants were taking enormous doses of narcotics. How could they experience such exaggerated pain? The experiment was Hutchinson’s first encounter with a perplexing phenomenon called opioid-induced hyperalgesia (OIH). At high doses, opioid painkillers actually seem to amplify pain by changing signaling in the central nervous system, making the body generally more sensitive to painful stimuli. “Just imagine if all the diabetic medications, instead of decreasing blood sugar, increased blood sugar,” says Jianren Mao, a physician and pain researcher at Massachusetts General Hospital in Boston who has studied hyperalgesia in rodents and people for more than 20 years. © 2016 American Association for the Advancement of Science

Keyword: Pain & Touch
Link ID: 22829 - Posted: 11.04.2016