Having high levels of a fat in the blood may increase someone's risk of developing Alzheimer's disease, a U.S. study suggests. Researchers are searching for better ways to screen, prevent and treat the mind-robbing disease that is projected to increase in prevalence worldwide. Scientists are looking for an accurate blood test to predict risk of Alzheimer's risk.Scientists are looking for an accurate blood test to predict risk of Alzheimer's risk. (Eliseo Fernandez/Reuters) Wednesday's issue of the journal Neurology includes a study on a biomarker in the blood that seems to predict the development of Alzheimer’s over the next decade. In the study, 99 women in the U.S. who were aged 70 to 79 and free of dementia when the study began had their blood tested. Investigators were checking levels of serum ceramides, a fatty compound found throughout the body that is associated with inflammation and cell death. Over the nine year study, 27 women developed dementia and 18 of those were diagnosed with probable Alzheimer's disease. Women who had the highest levels of the biomarker were 10 times more likely to develop Alzheimer's disease than women with the lowest levels, study author Michelle Mielke, an epidemiologist with the Mayo Clinic in Rochester, Minn., and her co-authors found. © CBC 2012

Keyword: Alzheimers
Link ID: 17065 - Posted: 07.19.2012

By Victoria Gill BBC Nature Seabirds are able to pick out their relatives from smell alone, according to scientists. In a "recognition test", European storm petrels chose to avoid the scent of a relative in favour of approaching the smell of an unrelated bird. The researchers think this behaviour prevents the birds from "accidentally inbreeding". The study is the first evidence that birds are able to sniff out a suitable mate. It is published in the journal Animal Behaviour. Lead researcher Francesco Bonadonna, from the Centre of Functional and Evolutionary Ecology in Montpellier, France, told BBC Nature that the birds used smell to recognise and communicate their "genetic compatibility". Sniffing out a genetically suitable mate is a well-known phenomenon in mammals. But until recently, scientists thought that birds relied on vision and sound when choosing a partner. According to Dr Bonadonna, the fact that they use odours explains how these birds manage to return to their family colony to breed and avoid mating with a relative. European storm petrels remain in the colony they are born in throughout their life, so this site is also home to several of their family members. BBC © 2012

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 17064 - Posted: 07.19.2012

Emma Marris Large-brained animals may be less likely to go extinct in a changing world, perhaps because they can use their greater intelligence to adapt their behaviour to new conditions, according to an analysis presented to a meeting of conservation biologists this week. The finding hints at a way to prioritize future conservation efforts for endangered species. Brain size relative to body size is fairly predictable across all mammals, says Eric Abelson, who studies biological sciences at Stanford University in Palo Alto, California. “As body size grows, brain size grows too, but at slower rate,” he says. Plotting brain size against body size creates a tidy curve. But some species have bigger or smaller brains than the curve would predict for their body size. And a bigger brain-to-body-size ratio usually means a smarter animal. Abelson looked at the sizes of such deviations from the curve and their relationships to the fates of two groups of mammalian species — ‘palaeo’ and ‘modern’. The palaeo group contained 229 species in the order Carnivora from the last 40 million years, about half of which are already extinct. The modern group contained 147 species of North American mammals across 6 orders. Analysis of each group produced similar results: species that weighed less than 10 kilograms and had big brains for their body size were less likely to have gone extinct or be placed on the International Union for Conservation of Nature red list for endangered species. For species larger than about 10 kilograms, the advantage of having a large brain seems to be swamped by the disadvantage of being big. Large species tend to reproduce later in life, have fewer offspring, require more resources and larger territories, and catch the attention of humans, either as food or as predators. Hunting pressure or reductions in available space can hit them particularly hard. © 2012 Nature Publishing Group

Keyword: Evolution
Link ID: 17063 - Posted: 07.18.2012

By Jennifer Viegas Dolphins may use complex nonlinear mathematics when hunting, according to a new study that suggests these brainy marine mammals could be far more skilled at math than was ever thought possible before. Inspiration for the new study, published in the latest Proceedings of the Royal Society A, came after lead author Tim Leighton watched an episode of the Discovery Channel's "Blue Planet" series and saw dolphins blowing multiple tiny bubbles around prey as they hunted. "I immediately got hooked, because I knew that no man-made sonar would be able to operate in such bubble water," explained Leighton, a professor of ultrasonics and underwater acoustics at the University of Southampton, where he is also an associate dean. "These dolphins were either 'blinding' their most spectacular sensory apparatus when hunting -- which would be odd, though they still have sight to reply on -- or they have a sonar that can do what human sonar cannot…Perhaps they have something amazing," he added. Leighton and colleagues Paul White and student Gim Hwa Chua set out to determine what the amazing ability might be. They started by modeling the types of echolocation pulses that dolphins emit. The researchers processed them using nonlinear mathematics instead of the standard way of processing sonar returns. The technique worked, and could explain how dolphins achieve hunting success with bubbles. © 2012 Discovery Communications, LLC.

Keyword: Evolution
Link ID: 17062 - Posted: 07.18.2012

Researchers have linked newly discovered gene mutations to some cases of the progressive fatal neurological disease amyotrophic lateral sclerosis — ALS, also known as Lou Gehrig’s disease. Shedding light on how ALS destroys the cells and leads to paralysis, the researchers found that mutations in this gene affect the structure and growth of nerve cells. ALS attacks motor neurons, the nerve cells responsible for controlling muscles. People with ALS experience such early symptoms as limb weakness or swallowing difficulties. In most people, the disease leads to death three to five years after symptoms develop, usually as a result of respiratory failure. Scientists at the University of Massachusetts Medical School, Worcester, collaborated with international ALS researchers to search for gene mutations in two large families with an inherited form of ALS. The researchers used a technique to decode only the protein-encoding portions of DNA, known as the exome, allowing an efficient yet thorough search of the DNA regions most likely to contain disease-causing mutations. This deep sequencing of the exome led to the identification of several different mutations in the gene for profilin (PFN1) which were present only in the family members that developed ALS. Further investigations of 272 other familial ALS cases across the world showed that profilin mutations were also found in a small subset (about 1 to 2 percent) of the familial ALS cases studied. The protein profilin is a key part of the creation and remodeling of a nerve cell's scaffolding or cytoskeleton. In fly models, disrupting profilin stunts the growth of axons — the long cell projections used to relay signals from one neuron to the next or from motor neurons to muscle cells. After identifying the PFN1 mutations in ALS patients, the researchers demonstrated that these mutations inhibited axon growth in laboratory-grown motor neurons as well. They also found that mutant profilin accumulated in clumps in neural cells, as has been seen for other abnormal proteins associated with ALS, Parkinson's and Alzheimer's.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 17061 - Posted: 07.18.2012

By Ella Davies Reporter, BBC Nature Promiscuous dumpling squid take 30 minutes to return to normal swimming speed after mating, say scientists. The short-lived cephalopods, named for their rotund shape, are known to mate with as many partners as possible. Researchers studying this behaviour found that swimming endurance was halved after mating for both sexes. They described mating as "costly" for the squid because it reduced the energy available for avoiding predators and feeding. The study of wild-caught squid is published in the Royal Society journal Biology Letters. A dumpling squid Dumpling squid hide from predators amongst sea-grass or buried in silty seabeds during the day "The squid mate for up to three hours and the male must physically restrain the female during this time," said researcher Amanda Franklin from the University of Melbourne, Australia. "It was exciting for us to show that this affects their physical abilities after mating because this has not been shown before." Dumpling squid (Euprymna tasmanica) are members of the bobtail squid family and found along the southern coast of Australia. BBC © 2012

Keyword: Sexual Behavior
Link ID: 17060 - Posted: 07.18.2012

By Scicurious Think about what happens when you walk. Really THINK about it. What does it take to walk? Well, your feet and legs have to move (far more complicated than they look), which means your muscles have to move, which means your nerves have to control your muscles, which means your brain has to send the signals in the first place. All of this is based on further information, knowing where you are in space and where you’re going, how fast you need to get there. And then there’s even more! How do you know where you are? How do you know how fast you’re going? How do you know which direction you’re headed? And behind all of this are thousands and millions of neurons firing, together and separately. And underlying THAT are thousands of biochemical processes which allow the neurons to fire… …now take that walking speed, and make it a run. The sheer number of neurobiological processes and number of things that need to happen to make you walk into your workplace every morning is the kind of thing that makes neuroscientists stop in their tracks with wonder. And today, we’re going to talk about a paper that may have worked out a tiny piece of how the brain might deal with things like increased speed. How does your brain keep up with your feet? By running a little faster. To understand how this works. We need to talk about two major things: place neurons, and oscillatory networks. © 2012 Scientific American

Keyword: Movement Disorders
Link ID: 17059 - Posted: 07.18.2012

A widely prescribed drug for multiple sclerosis may not slow the disease from progressing, a British Columbia study shows. Beta interferons are prescribed for the relapse-remitting form of MS, which affects about 85 per cent of people with the disease in Canada. As the name suggests, people with relapsing-remitting MS have flare-ups when new symptoms appear or olds ones return or worsen. There are also periods of remission with partial or full recovery. "In clinical trial situations, it has been quite evident for years that patients receiving beta interferon treatment have reduced frequency of relapses as well as reduced frequency of new lesions seen on MRI," Dr. Joel Oger, who is also a neurologist with the UBC Hospital MS Clinic, said in a release. "This study following a large number of patients for a long time in 'real life situation' does not show an association of the beta interferons with long term disability and tends to confirm a more modern way of understanding MS: relapses may not be responsible for long term disability in all patients and another mechanism might be at work as well." The study in Wednesday's issue of the Journal of the American Medical Association compared 868 people prescribed the drug with 829 who were untreated as well as 959 who were treated before interferon beta was approved. © CBC 2012

Keyword: Multiple Sclerosis
Link ID: 17058 - Posted: 07.18.2012

By Marissa Fessenden Autistic children struggle with many obstacles, including learning to speak. And, experts have noted, if these children learn verbal skills by age five, they tend to become happier and higher-functioning adults than do their nonverbal peers. Thirty years ago, psychiatrists expected only half of all autistic children would gain speaking abilities. Recent studies, however, indicate that as many as 80 percent of children with autism can learn to talk. One such study in 2006 showed that toddlers who received intensive therapy aimed at developing foundational oral language skills made significant gains in their ability to communicate verbally. Now researchers have followed up with a number of those kids and found that most of them continued to reap the benefits of that therapy years after it had ended. Several early behaviors build a foundation for language. These abilities have also been linked to whether a child can anticipate another person's mental state and use that understanding to explain and predict behavior. Developing this "theory of mind" may be a central difficulty for children with autism. Kasari's team targeted two of the early behaviors in their work: The first is the ability to engage in symbolic play, in which one object represents another—a child pretending a doll is his parent, for instance. The second is joint attention, wherein a child divides focus between an object and another person. This behavior can be thought of as "sharing looks." For example, when a child points to show a playmate a toy train, she looks at the moving train and checks to see if her playmate is engaged. In the initial study, Connie Kasari of the University of California, Los Angeles, and her colleagues evaluated 58 children between three and four years old in a randomized controlled study. © 2012 Scientific American,

Keyword: Autism; Language
Link ID: 17057 - Posted: 07.18.2012

By Kay Lazar, Globe Staff If all goes according to plan, 1,000 older people who have no symptoms of Alzheimer’s disease, but who have an abnormal protein in their brains believed to be a hallmark of the illness, will be selected to test whether drugs can hold off the disease in a first of its kind study to be led by Boston scientists. The proposed study, detailed Tuesday at the Alzheimer’s Association International Conference in Vancouver, received a preliminary thumbs up earlier this month from the National Institutes of Health, but the project’s leaders are awaiting a final decision on funding the project, expected in September. “In this tough time of federal funding, we are keeping our fingers very tightly crossed,” lead researcher Dr. Reisa Sperling, an Alzheimer’s specialist at Brigham and Women’s Hospital, said in a phone interview. Recent drug trials aimed at clearing the abnormal amyloid proteins in the brains of Alzheimer’s patients have produced disappointing results, with no apparent easing of symptoms, and researchers think that’s because the drugs were used too late. Scientists believe that more than 50 percent of certain critical brain cells are already lost by the time a patient displays even mild cognitive impairment. There is no known cure for Alzheimer’s disease. Sperling’s study would enroll 1,000 adults over age 70 who have amyloid plaques revealed by brain scans and who are exhibiting very subtle cognitive problems that are typically reported in people years before they are diagnosed with Alzheimer’s. © 2012 NY Times Co.

Keyword: Alzheimers
Link ID: 17056 - Posted: 07.18.2012

By ANDREW POLLACK A drug already on the market that treats immune disorders may help stabilize patients with Alzheimer’s disease for up to three years, according to the results of a tiny study presented at a conference on Tuesday. All four patients who received the optimal dose of the drug, Gammagard from Baxter International, had no decline in several measures of cognition and daily function for three years, researchers said. Dr. Norman Relkin of Weill Cornell Medical College, the lead investigator of the study, said the results were “remarkable” because patients with Alzheimer’s disease typically worsen within 12 months. “If we have a patient who goes 18 months without changing we begin to doubt they have Alzheimer’s,” Dr. Relkin said in a news conference at the Alzheimer’s Association International Conference in Vancouver, British Columbia, where the results were presented. But some experts not involved in the trial said it was premature to conclude that the drug was responsible for the stabilization. “There will be some patients who at three years don’t have a decline” even without an experimental therapy, said Dr. Rachelle S. Doody, director of the Alzheimer’s Disease and Memory Disorders Center at Baylor College of Medicine. She said some patients go six or eight years without worsening. © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 17055 - Posted: 07.18.2012

By Tina Hesman Saey Identical twins aren’t perfect carbon copies of each other even at birth. Twins emerge from the womb carrying different chemical marks on their DNA that influence the activity of individual genes, a new study shows. Known as epigenetic markers, these alterations don’t change the underlying genetic information. But by regulating the activity of certain genes, they can profoundly influence how the DNA blueprint is used to create and operate a living organism. Past research has shown that identical twins bear some differences in epigenetic markers. But those differences were thought to arise after birth, as twins have different life experiences and encounter different environments. The new study — the first to measure epigenetic profiles in newborns — suggests that subtle differences in conditions within the womb can leave marks on fetal DNA that may have long-term consequences for adult health. These differing chemical tags may help explain why identical twins look slightly different, have their own personalities and may have different susceptibility to diseases. Jeffrey Craig, a molecular and cell biologist at Murdoch Childrens Research Institute in Parkville, Australia, and his colleagues report the findings online July 15 in Genome Biology. Identical twins are on average more epigenetically similar than fraternal twins, the researchers found. The similarity was probably not due to sharing a womb, but could be attributed partially to genetics and partially to chance, they suggest. © Society for Science & the Public 2000 - 2012

Keyword: Epigenetics; Genes & Behavior
Link ID: 17054 - Posted: 07.18.2012

By PAM BELLUCK The way people walk appears to speak volumes about the way they think, so much so that changes in an older person’s gait appear to be an early indicator of cognitive impairment, including Alzheimer’s disease. Five studies presented at the Alzheimer’s Association International Conference in Vancouver this month provide striking evidence that when a person’s walk gets slower or becomes more variable or less controlled, his cognitive function is also suffering. Thinking skills like memory, planning activities or processing information decline almost in parallel with the ability to walk fluidly, these studies show. In other words, the more trouble people have walking, the more trouble they have thinking. “Changes in walking may predate actually observable cognitive changes in people who are on their way to developing dementia,” said Molly Wagster, chief of the National Institute on Aging’s behavioral and systems neuroscience branch. Experts said the studies could lead to developing a relatively simple tool that doctors could use to forecast, if not diagnose, possible Alzheimer’s disease. “You can probably just watch them walk down the hall in your office and look for people who are starting to show deterioration in their gait and have no other explanation for it,” said William Thies, the chief medical and scientific officer for the Alzheimer’s Association. “If gait begins to deteriorate, we begin to have a conversation about how is your memory.” © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 17053 - Posted: 07.17.2012

By Linda Carroll Teens who play on more than one sports team during the year are far less likely to become overweight or obese, a new study suggests. In fact, Dartmouth College researchers concluded that the obesity rate among high schoolers could be cut by more than 26 percent if all teens signed up for multiple team sports, according to the study, published today in the journal Pediatrics. The researchers also found that kids who bike or walk to school are less likely to become obese. If every kid in the country biked or walked to school at least four days a week, then obesity could be cut by 22 percent, they reported. “I know that coordinating schedules can be difficult in terms of getting kids to practices and games,” said study co-author Keith Drake, a post doctoral research fellow at the Hood Center for Children and Families at the Geisel School of Medicine at Dartmouth. “But it does look to us like getting kids involved in sports may be the best chance we have to get them physically active and to help them maintain a healthy body weight.” Playing on a single team didn’t appear to have a strong effect. Still, Drake said: “Playing on one team is probably better than playing on none.” Drake and his colleagues surveyed 1,718 New Hampshire and Vermont high school students and their parents for the new study. The new report is part of a seven-year review of adolescent health that started in 2002 and included five separate surveys of the kids and their parents. © 2012 NBCNews.com

Keyword: Obesity; Development of the Brain
Link ID: 17052 - Posted: 07.17.2012

By JOHN NOBLE WILFORD Who are we, and where did we come from? Scientists studying the origin of modern humans, Homo sapiens, keep reaching deeper in time to answer those questions — toward the last common ancestor of great apes and humans, then forward to the emergence of people more and more like us in body and behavior. Their research is advancing on three fronts. Fossils of skulls and bones expose anatomical changes. Genetics reveals the timing and place of the Eve of modern humans. And archaeology turns up ancient artifacts reflecting abstract and creative thought, and a growing self-awareness. Just last month, researchers made the startling announcement that Stone Age paintings in Spanish caves were much older than previously thought, from a time when Neanderthals were still alive. To help make sense of this cascade of new information, a leading authority on modern human evolution — the British paleoanthropologist Chris Stringer — recently sat for an interview in New York that ranged across many recent developments: the evidence of interbreeding between Neanderthals and Homo sapiens; the puzzling extinct species of little people nicknamed the hobbits; and the implications of a girl’s 40,000-year-old pinkie finger found in a Siberian cave. Dr. Stringer, an animated man of 64, is an anthropologist at the Natural History Museum in London and a fellow of the Royal Society. But he belies the image of a don: He showed up for our interview wearing a T-shirt and jeans, looking as if he had just come in from the field. © 2012 The New York Times Company

Keyword: Evolution
Link ID: 17051 - Posted: 07.17.2012

by Michael Marshall As Katie Holmes has just demonstrated, sometimes a marriage can hit rocky patches. The question is, what do you do then? Marge Simpson has expounded (and demonstrated) one approach to the problem: "You've got to stick it out, even if you picked the loser… to the bitter end." That's one solution, but it's not the one the wandering albatross applies. Despite forming lifelong pair-bonds, wandering albatrosses are far from paragons of steadfast monogamy. They may stick with their partners year after year, but their relationships are distinctly open. A long-term study of one population offers a possible explanation for the birds' cheating hearts. Stick with me Wandering albatrosses have the largest wingspan of any bird, at 3.5 metres or more, although other birds are heavier. As their name suggests, they spend most of their lives wandering aimlessly around the chilly Southern Ocean, hunting for fish and other marine animals. Every other year they breed, returning to one of a number of isolated islands. One such site is Marion Island in the southern Indian Ocean, which been continuously monitored since 1987. Once they've reached maturity, wandering albatrosses find a long-term partner. Courting pairs stand facing each other, spread their wings and cry out. Each bird also points its beak skywards before clapping it. Once the bond is established, which can take three years, the pair will normally reunite every two years until one of them dies. Females prefer males of about their own age, who should live as long as they do. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 17050 - Posted: 07.17.2012

By Janet Raloff A resin in the most commonly used white composite dental fillings may be linked to subtle neuropsychological deficits in children. The association appears in reanalyzed data collected from 434 children as part of a trial begun roughly a decade ago. The original study was designed to probe for IQ or other neurobehavioral impacts of the mercury that can be released by metal-amalgam dental fillings. Half of the kids received amalgam fillings for cavities in back teeth, the rest got composite back fillings. Cavities in front teeth always got composite fillings. Wherever composites were used, baby teeth got a urethane-based resin, while permanent teeth got a resin called bis-GMA that is derived from bisphenol A, or BPA. BPA can mimic the hormonal activity of estrogen and exposure in the womb has been linked to behavioral changes in mice and young children. The 6- to 10-year olds were then followed for five years, with the children or their parents periodically participating in assessments of a kid’s mood, behaviors (including aggression), attitudes at school and interpersonal relationships. That original study, published in 2006, turned up no problems associated with metal fillings. But the research did hint that composite fillings might be worrisome. After reanalyzing their data, the researchers now find that children receiving bis-GMA fillings did exhibit low-level changes on behavioral assessments. © Society for Science & the Public 2000 - 2012

Keyword: Neurotoxins; Intelligence
Link ID: 17049 - Posted: 07.17.2012

By WILLIAM J. BROAD Scientists have long known that man-made, underwater noises — from engines, sonars, weapons testing, and such industrial tools as air guns used in oil and gas exploration — are deafening whales and other sea mammals. The Navy estimates that loud booms from just its underwater listening devices, mainly sonar, result in temporary or permanent hearing loss for more than a quarter-million sea creatures every year, a number that is rising. Now, scientists have discovered that whales can decrease the sensitivity of their hearing to protect their ears from loud noise. Humans tend to do this with index fingers; scientists haven’t pinpointed how whales do it, but they have seen the first evidence of the behavior. “It’s equivalent to plugging your ears when a jet flies over,” said Paul E. Nachtigall, a marine biologist at the University of Hawaii who led the discovery team. “It’s like a volume control.” The finding, while preliminary, is already raising hopes for the development of warning signals that would alert whales, dolphins and other sea mammals to auditory danger. Peter Madsen, a professor of marine biology at Aarhus University in Denmark, said he applauded the Hawaiian team for its “elegant study” and the promise of innovative ways of “getting at some of the noise problems.” But he cautioned against letting the discovery slow global efforts to reduce the oceanic roar, which would aid the beleaguered sea mammals more directly. © 2012 The New York Times Company

Keyword: Hearing; Animal Communication
Link ID: 17048 - Posted: 07.17.2012

Rebecca Goldin, Ph.D., Cindy S. Merrick With the news media telling us that neuroscience – and brain scans – can explain everything from a global pandemic of Justin Bieber fever to whether you are likely to stay with your spouse, we investigate what neuroscience can and can’t tell us about who we are and why we do the things we do. In the first part of an ongoing series, we look at functional magnetic resonance imaging, and whether it’s really the window on the mind that some in the media – and science – would have us believe. Gone are the days when the only people who believed in technologies that could read minds were distinguishable from the rest of us by their tin foil hats. With the advent of functional magnetic resonance imaging (fMRI), we are able to see, in near-video quality, the ebb and flow of a live mind at work. Or so it seems. Something, for certain, is at work, and there are lots of people willing to tell you they know exactly how to interpret what we can see. Certainly this new technology has already produced fascinating results: surgeons use it real-time to avoid critical regions while operating on brain tumors; physicians use it to look for changes in the brain activity of stroke victims as they experience physical rehabilitation; and fMRI data showing activity in the brains of patients thought to be in a vegetative state may be blurring the line that defines consciousness. Along with these advances, though, have appeared many somewhat less credible stories. The media reports claims ranging from fMRI’s ability to detect lies to its predicting future addictive behavior or determining whether or not you really love your spouse, or, maybe, your iPhone. Already, attempts have been made to use fMRI as admissible evidence of lie detection in court (so far, they have failed); and in another court case, fMRI results and a neuroscientist’s testimony were admitted in the sentencing hearing. The data were used as evidence that the defendant, a violent offender, was psychopathic.

Keyword: Brain imaging
Link ID: 17047 - Posted: 07.17.2012

By Dwayne Godwin and Jorge Cham In 1953, Henry Molaison underwent radical surgery in an attempt to stop his epileptic seizures... © 2012 Scientific American,

Keyword: Learning & Memory; Epilepsy
Link ID: 17046 - Posted: 07.16.2012