By Tina Hesman Saey Stabilizing the ties that bind a protein important in Parkinson’s disease to its buddies might help fend off the disease, a new study of the protein’s structure suggests. Alpha-synuclein builds up in tough aggregates in the brains of patients with Parkinson’s disease. Researchers thought that this protein was normally a floppy, snakelike molecule. But now, neuroscientist and neurologist Dennis Selkoe of Brigham and Women’s Hospital and Harvard Medical School and his colleagues show that alpha-synuclein normally forms bands of four molecules in living cells. These quartets (scientists call them tetramers) of alpha-synuclein molecules resist the clumping that leads single molecules of the protein down the path to brain cell destruction, Selkoe and colleagues report online August 14 in Nature. Discovering that alpha-synuclein works in groups of four could be important in treating or preventing Parkinson’s disease, says Patrik Brundin, a neuroscientist at Lund University in Sweden. The findings suggest that loner alpha-synuclein molecules could be “part of the ‘bad guy’ pathway, and stabilizing it as a tetramer might help avoid the disease,” he says. No one yet knows whether quartets of alpha-synuclein disintegrate into single molecules in the brains of people with Parkinson’s disease, leading to big brain-cell-killing plaques. Studies comparing normally aging brains with those of people with the disease may help answer those and other questions raised by the study, Brundin says. © Society for Science & the Public 2000 - 2011

Keyword: Parkinsons; Genes & Behavior
Link ID: 15681 - Posted: 08.16.2011

By Victoria Gill Science reporter, BBC Nature Same-sex pairs of monogamous birds are just as attached and faithful to each other as those paired with a member of the opposite sex. The insight comes from a study of zebra finches - highly vocal, colourful birds that sing to their mates, a performance thought to strengthen the pair's bond. Scientists found that same-sex pairs of finches sang to and preened each other just like heterosexual pairs. The study is reported in the journal Behavioural Ecology and Sociobiology. A displaying pair of king penguins Male king penguins have been seen to "flirt" with other males in the colony Lead researcher Julie Elie from the University of California Berkeley said that the research showed that "relationships in animals can be more complicated than just a male and a female who meet and reproduce, even in birds". Dr Elie and her colleagues are interested in zebra finches' behaviour. The birds establish life-long relationships and are highly social; males sing to their mates, the birds preen each other and pairs share a nest. "I'm interested in how animals establish relationships and how [they] use acoustic communication in their social interactions," Dr Elie told BBC Nature. BBC © 2011

Keyword: Sexual Behavior
Link ID: 15680 - Posted: 08.16.2011

An obesity scoring system developed in Edmonton to help predict the risk of dying for overweight and obese people could be used to prioritize patients for weight-loss surgery. The Edmonton Obesity Staging System (EOSS) is modeled on similar scores used to predict the extent and severity of other diseases such as a cancer, heart disease and mental illness. The new model emphasizes how at-risk the patient is, not how much they weigh, says Dr. Arya Sharma.The new model emphasizes how at-risk the patient is, not how much they weigh, says Dr. Arya Sharma. The new scale includes five stages of obesity based on traditional measurements such as body mass index and waist-to-hip ratios, as well as clinical measurements of medical conditions tied to obesity, such as Type 2 diabetes, hypertension and heart disease. In Monday's issue of the Canadian Medical Association Journal, Dr. Arya Sharma of the University of Alberta and his co-authors used the tool to predict death with data from a U.S. population survey of 8,143 people who were followed for 16 years. About 77 per cent of them were overweight or obese. 5 stages of obesity scale The obesity scale has five stages. Criteria include: Stage 0: No apparent obesity-related risk factors (e.g., high blood pressure, cholesterol and/or glucose levels), no physical symptoms or limitations. © CBC 2011

Keyword: Obesity
Link ID: 15679 - Posted: 08.16.2011

By Genevra Pittman Siblings of kids with autism have a higher risk of being diagnosed with the disorder than previously believed, suggests a new study. The analysis of more than 600 three-year-olds with an older autistic sibling found that almost one in five of them had an autism spectrum disorder, which includes Asperger’s syndrome and similar conditions. That suggests pediatricians need to keep an extra eye on those siblings, even as toddlers -- because early interventions with therapy and extra support might help keep their symptoms to a minimum, researchers said. “We know that the brain at young ages is more amenable to change,” said study author Wendy Stone, of the University of Washington Autism Center in Seattle. “When children are showing signs (of autism) even before the diagnosis is official, we need to start thinking about, how can we help parents within the course of their everyday activities to promote their child’s social and emotional development?” she told Reuters Health. The findings, she said, also show that autism rates -- now estimated at about one in every 110 U.S. kids -- probably aren’t going to decrease anytime soon. Previous studies estimated that between 3 and 14 percent of autistic kids’ younger siblings also had the condition. Copyright 2011 Thomson Reuters

Keyword: Autism; Genes & Behavior
Link ID: 15678 - Posted: 08.16.2011

By Bruce Bower Now hear this: A mother’s encouraging words heard over the phone biologically aid her stressed-out daughter about as much as in-person comforting from mom and way more than receiving instant messages from her. That’s consistent with the idea that people and many other animals have evolved to respond to caring, familiar voices with hormonal adjustments that prompt feelings of calm and closeness, say biological anthropologist Leslie Seltzer of the University of Wisconsin–Madison and her colleagues. Written exchanges such as instant messaging, texting and Facebook postings can’t apply biological balm to frazzled nerves, the researchers propose in a paper published online July 29 in Evolution and Human Behavior. Seltzer’s group found that 7- to 12-year-old girls who talked to their mothers in person or over the phone after a stressful lab task displayed drops in levels of cortisol, a stress hormone, accompanied by the release of oxytocin, a hormone linked to love and trust between partners in good relationships. Girls who instant messaged with their mothers after the lab challenge showed no oxytocin response and their cortisol levels rose as high as those of girls who had no contact with their mothers. “At least in our subjects, instant messaging falls short of the endocrine payoff of speech or physical contact with a loved one after a stressful event,” Seltzer says. © Society for Science & the Public 2000 - 2011

Keyword: Stress; Hormones & Behavior
Link ID: 15677 - Posted: 08.13.2011

Sandrine Ceurstemont, video producer Think you can tell if an object is moving? Think again. This illusion created by Ikuya Murakami from the University of Tokyo, Japan, shows that we can perceive a wobble when an object is actually static. In the video above, fix your eyes on the yellow dot in the first animation. As the ring flickers, the static centre of the circle seems to wobble. In the second demo, a similar effect is perceived once your eyes have adapted to a flashing pattern. After staring at a yellow dot for about 30 seconds, a static version of the moving pattern suddenly appears. The centre of the circle, which wasn't previously moving, should seem to wobble briefly. Murakami and his team found that we perceive this effect because of tiny eye movements that occur when we fix on a static point. We're not usually aware of these movements because our visual system automatically counteracts the shake when it processes what we see. However a static pattern surrounded by a flickering one seems to confuse our brain because eye movements are registered differently between flickering and static regions. Murakami's work is the first to show that our visual system needs to have constant access to the speed of our eye movements to compensate for them. Our vision evolved to make the correction so that we can quickly spot motion in our environment - an approaching predator, for example. But the illusion shows that it has problems dealing with flicker. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 15676 - Posted: 08.13.2011

By SINDYA N. BHANOO Although baby humans and baby chimpanzees both start out with undeveloped forebrains, a new study reports that the human brain increases in volume much more rapidly early on. The growth is in a region of the brain known as the prefrontal cortex and is part of what makes humans cognitively advanced compared with other animals, including the chimpanzee, our closest relative. The prefrontal cortex plays a major role in decision-making, self-awareness and creative thinking. Tetsuro Matsuzawa, a zoologist at Kyoto University in Japan, and his colleagues performed magnetic resonance imaging scans on three young chimpanzees over about six years, starting when the chimps were 6 months old. The researchers compared these scans with M.R.I. scans taken of human infants and children. They found that the white matter in the prefrontal cortex of chimpanzees does not grow as rapidly as it does in humans. Their findings appear in the journal Current Biology. That the brains of both animals undergo significant growth indicates that brain development in both is shaped by life experience. This may be why human babies and chimp babies share some similarities — like the impulse to smile at caregivers. But the rapid development of the prefrontal cortex in humans may contribute to superior skills in communication and social interaction. © 2011 The New York Times Company

Keyword: Development of the Brain; Evolution
Link ID: 15675 - Posted: 08.13.2011

Women with depression may also be at increased risk of having a stroke, US researchers suggest. A study of over 80,000 women found those with a history of depression had a 29% increased risk of stroke. The research, in Stroke: Journal of the American Heart Association, said doctors should be aware people with depression may neglect their general health. UK stroke experts said depression alone was unlikely to increase stroke risk. Indicator The women, all aged 54-79, who were all taking part in the long-running Nurses' Health Study which has been following women across the US since the mid 1970s. In this study, the researchers looked at data from 2000 to 2006. None had had a stroke before the study began, while 22% had been diagnosed with depression. Compared to women without a history of depression, depressed women were more likely to be single, smokers and less physically active. They were also slightly younger, had a higher body mass index and conditions such as high blood pressure, heart disease and diabetes. BBC © 2011

Keyword: Depression; Stroke
Link ID: 15674 - Posted: 08.13.2011

By Laura Beil When it comes to the safety of dyeing food, the one true shade is gray. Artificial colorings have been around for decades, and for just about as long, people have questioned whether tinted food is a good idea. In the 1800s, when merchants colored their products with outright poisons, critics had a pretty good case. Today’s safety questions, though, aren’t nearly so black and white — and neither are the answers. Take the conclusions reached by a recent government inquiry: Depending on your point of view, an official food advisory panel either affirmed that food dyes were safe, questioned whether they were safe enough or offered a conclusion that somehow merged the two. It was a glass of cherry Kool-Aid half full or half empty. About the only thing all sides agree on is that there would be no discussion if shoppers didn’t feast with their eyes. Left alone, margarine would be colorless, cola wouldn’t be dark, peas and pickles might not be so vibrantly green, and kids cereals would rarely end up with the neon hues of candy. But as the 1990s flop of Crystal Pepsi showed, consumers expect their food to look a certain way. Some of the earliest attempts to dye food used substances such as chalk or copper — or lead, once a favorite for candy — that turned out to be clearly harmful. Most of the added colors in use today were originally extracted from coal tar but now are mostly derived from petroleum. © Society for Science & the Public 2000 - 2011

Keyword: ADHD; Attention
Link ID: 15673 - Posted: 08.13.2011

By Susan Milius Acts of apparent altruism in European paper wasps can be explained by plain old self-interest, a new study finds. Polistes dominulus females can either establish their own nests to raise young or join other females for joint homemaking. In those joint nests, though, one female fights her way to the top and does most of the egg-laying while the others do most of the drudge work in taking care of the top wasp’s young. When a subordinate helps her sister, that’s not hard to explain: The underling may not end up with her own offspring, but her reproductive success includes an indirect share of her sister’s brood, because relatives share genes. Forgoing her own direct offspring counts as a kind of altruism, in which an individual helping kin trades direct for indirect benefit. Either way, the wasp’s self-interest is served. But some 15 to 35 percent of co-queens slaving away are not closely related to the top wasp, so biologists have been puzzled about why those strangely helpful females don’t go off to found their own nests. They do it because joining an unrelated queen’s nest offers a chance of grabbing the throne, says Ellouise Leadbeater of the Zoological Society of London. She and her colleagues tracked the fortunes of 1,113 foundresses in 228 nests in southern Spain. In this epic population analysis, females that started out as subordinates to a nonrelative occasionally took over the whole nest and laid their own eggs. Their triumphs were rare but dramatic enough so that, overall, the strategy worked out better than being a single mom: Lone nest foundresses hardly managed to produce any offspring, the researchers report in the Aug. 12 Science. © Society for Science & the Public 2000 - 2011

Keyword: Evolution
Link ID: 15672 - Posted: 08.13.2011

By Kenneth I. Kaitin and Christopher P. Milne Schizophrenia, depression, addiction and other mental disorders cause suffering and cost billions of dollars every year in lost productivity. Neurological and psychiatric conditions account for 13 percent of the global burden of disease, a measure of years of life lost because of premature mortality and living in a state of less than full health, according to the World Health Organization. Despite the critical need for newer and better medications to treat a range of psychiatric and neurodegenerative diseases, including Alzheimer’s and Parkinson’s, drugs to treat these diseases are just too complex and costly for big pharmaceutical companies to develop. The risk of spending millions on new drugs only to have them fail in the pipeline is too great. That’s why many big drug companies are pulling the plug on R&D for neuropsychiatric and other central nervous system (CNS) medicines. Our team at the Tufts Center for the Study of Drug Development has arrived at this conclusion after conducting surveys of pharmaceutical and biotechnology companies about the drug development process. These surveys allow us to generate reliable estimates of the time, cost and risk of designing new drugs. Our analyses show that central nervous system agents are far more difficult to develop than most other types. © 2011 Scientific American,

Keyword: Schizophrenia; Depression
Link ID: 15671 - Posted: 08.11.2011

by Anil Ananthaswamy The able-bodied dreams of people with a variety of disabilities challenge the theory that dreams are mere echoes of your day "WE HAD to flee. After a frantic race I started walking, carrying my daughter in my arms..." No matter how exciting to the dreamer, listening to people recount their dreams is notoriously dull. But reports such as this one, from someone who was born paralysed from the waist down, are perhaps more interesting. This is because a flurry of recent dream studies in people with disabilities are challenging our understanding of why we dream. The results seem to suggest that dreams, besides being a surreal echo of our waking lives, have a reality of their own: they may even spring from innate, fully functional representations of our body and sensory perceptions that do not always match real-life situations. The idea that dreams are linked to our waking reality - known as the continuity hypothesis - can be traced back to Sigmund Freud. The basic premise is that our dreams are determined by the thoughts, feelings and events that we have experienced during our waking hours, whether recently or further into the past. While this hypothesis cannot account for everything - why we occasionally fly in our dreams, for example - it is the dominant idea, says dream researcher Martin Schredl at the Central Institute of Mental Health in Mannheim, Germany. He says there is a thematic continuity between waking and dreaming: "Dreams evoke specific emotions and reactions within the dreamer, and these are very closely related to actual waking-life issues." © Copyright Reed Business Information Ltd.

Keyword: Sleep
Link ID: 15670 - Posted: 08.11.2011

By Nathan Seppa Breathing irregularities that rob the brain of oxygen during sleep may imperil a person’s ability to think straight. A study of women 65 and older finds that those with seriously disordered breathing have an increased risk of developing mild cognitive impairment or dementia in subsequent years, researchers report in the Aug. 10 Journal of the American Medical Association. Individuals with disordered breathing slow down or stop taking breaths during sleep and often must gasp to catch up. The condition includes sleep apnea, an abnormal pattern that deprives the brain of oxygen and intermittently interrupts the deep sleep needed for satisfying rest. Earlier, short-term studies linked disordered breathing to cognitive impairment, citing hypoxia, a lack of oxygen, as a culprit. But long-term data have been lacking. In the new study, physician Kristine Yaffe of the University of California, San Francisco, and her colleagues tested 298 women, average age 82, from 2002 to 2004 for sleep problems, monitoring each individual overnight and noting any stoppages of air flow in their breathing as well as arousals from sleep. About one-third of the patients had disordered breathing. None of these women was cognitively impaired at the time of the sleep test. After the test, patients were given their scores and told if they showed signs of severe sleep problems, says study coauthor Katie Stone, an epidemiologist at the California Pacific Medical Center in San Francisco. Whether they sought treatment is unknown, she says. © Society for Science & the Public 2000 - 2011

Keyword: Sleep; Alzheimers
Link ID: 15669 - Posted: 08.11.2011

By Tina Hesman Saey Rare genetic factors that lead to attention deficit hyperactivity disorder appear to be some of the same ones that cause autism, schizophrenia and other brain disorders. Previous studies have attempted – and mostly failed – to link common genetic variants to attention deficit hyperactivity disorder, better known as ADHD. A new study bolsters the idea that many different rare variants, some found only in single families or individuals, are responsible for the condition. What’s more, variants of the same genes associated with ADHD have also been linked to autism spectrum disorders, schizophrenia, bipolar disorder and intellectual disability. “This really gives substance to the argument that there are shared genetic links between neuropsychiatric disorders,” says child psychiatrist Russell Schachar of the Hospital for Sick Children in Toronto, who led the study with Stephen Scherer, a geneticist at the hospital. ADHD is one of the most common neuropsychiatric disorders, affecting about 7 percent of school-age children in the United States. It persists throughout life. People with the disorder may have trouble concentrating, act impulsively and be overly active. Symptoms fall on a continuum of severity, much like high blood pressure, says Josephine Elia, medical codirector of the Center for Management of ADHD at Children’s Hospital of Philadelphia. Up to 75 percent of people with autism spectrum disorders also have symptoms of ADHD, but researchers did not know if the genetic causes were the same as in people who have ADHD alone. © Society for Science & the Public 2000 - 2011

Keyword: ADHD; Genes & Behavior
Link ID: 15668 - Posted: 08.11.2011

Researchers at the National Institutes of Health have discovered in mice a molecular trigger that initiates myelination, the process by which brain cell networks are reinforced with an insulating material called myelin that speeds their ability to transmit messages. The myelination process is an essential part of brain development. Myelin formation is necessary for brain cells to communicate and it may contribute to development of skills and learning. The researchers showed that an electrical signal passing through a brain cell (neuron) results in the brain cell releasing the molecule glutamate. Glutamate, in turn, triggers another type of brain cell, called an oligodendrocyte, to form a point of contact with the neuron. Signals transmitted through this contact point stimulate the oligodendrocyte to make myelin protein and begin the process of myelination. In this process, the oligodendrocyte wraps myelin around axons— the long, cable-like projections that extend from each neuron. The myelination process is analogous to wrapping electrical tape around bare wires. Myelin formation Electrical signals transmitted from one neuron to the next are a basic form of communication in the brain. The myelin layers that oligodendrocytes wrap around neurons boost these signals so that they travel 50 times faster than before. The study was conducted by Hiroaki Wake, Philip R. Lee, and R. Douglas Fields.

Keyword: Glia
Link ID: 15667 - Posted: 08.11.2011

Alla Katsnelson Peggy Willocks was 44 when she was diagnosed with Parkinson's disease. It progressed quickly, forcing her to retire four years later from her job as a primary-school principal in Elizabethton, Tennessee. Soon, her condition had deteriorated so much that she was often unable to dress and feed herself, take care of basic hygiene or walk unaided across a room. Willocks enrolled in a trial for an experimental therapy called Spheramine, developed by Titan Pharmaceuticals, a biotechnology company in South San Francisco, California. Spheramine consists of cultured human retinal epithelial cells bound to specialized man-made carrier molecules. The cells are implanted into the brain, where it is hoped that they will produce the dopamine precursor levodopa, which can reduce the symptoms of Parkinson's disease. In August 2000, Willocks became the second person ever to receive the treatment. After having a steel halo — a stereotactic frame — bolted to her skull, she was put under general anaesthesia. Surgeons then used the frame and coordinates obtained from numerous magnetic resonance imaging (MRI) scans to pinpoint the location at which to drill. They then snaked a catheter through her brain's white matter to deliver the cells into the striatum. At first there was no effect, but Willocks says that after 6–8 months she began to feel better. The changes were always moderate and gradual, except for once, about nine months after her surgery, when she showed what her doctor called a "radical" improvement in balance. By a year after the treatment, she and the five other patients in the phase I trial showed an improvement in motor ability of 48%, and those gains largely held 4 years later1. © 2011 Nature Publishing Group,

Keyword: Parkinsons
Link ID: 15666 - Posted: 08.11.2011

by Sara Reardon Giving birth to twins is rough, especially in rural regions. They tend to be born smaller and weaker than single babies, and their mothers have more complications during childbirth. So why did twinning evolve? A new study in Gambia finds that women who have twins also tend to have single babies that are heavier than average at birth, which makes them more likely to survive. Since the 1950s, the U.K. Medical Research Council has been collecting data and providing medical care in Gambia. It's a highly unusual data set, says evolutionary anthropologist Rebecca Sear of Durham University in the United Kingdom, with a length and thoroughness that's "unheard of for populations without good access to medical care." Evolutionary biologist Ian Rickard of the University of Sheffield in the United Kingdom wondered whether the data could shed light on the biology of twins. Rickard and colleagues looked at the birth weights of 1889 single babies born to Gambian women over a 30-year period. Then they examined which of these mothers also had twins. Single babies born after twins were 226 grams heavier on average than single babies whose mothers had no twins, the team reports today in Biology Letters. This wasn't surprising, Rickard says, because carrying twins is thought to improve blood flow to the uterus and "prime" it for later children, allowing them to more easily receive nutrients. What did surprise the researchers was the discovery that when single babies were born before twins, the singles tended to be 134 grams heavier than average. © 2010 American Association for the Advancement of Science

Keyword: Evolution; Sexual Behavior
Link ID: 15665 - Posted: 08.11.2011

By Steve Connor, Science Editor One of the biggest studies ever undertaken into multiple sclerosis has identified 29 new genetic factors that are implicated in the development of the disease. The nature of the genes that have been linked with MS has demonstrated with a high degree of certainty that the root causes of the illness can be traced to the faulty functioning of the body's immune system, scientists said. Nearly 10,000 individuals with multiple sclerosis took part in the study and their genomes were scanned to find the genetic differences with the DNA of over 17,000 healthy people. The total number of genetic faults linked with the disease now amounts to 57. Alastair Compston, of the University of Cambridge, one of the lead authors of the study published in Nature, said there have been rival theories about what are the important factors implicated in triggering the disease, one of the most common neurological conditions affecting young adults. "Our research settles a long-standing debate on what happens first in the complex sequences of events that leads to disability in multiple sclerosis," he said. "This has important implications for future treatment strategies. It puts immunology right at the front end of the disease, absolutely." The study involved a relatively new technique called genome-wide scanning, which involves analysing the entire length of a patient's DNA for anomalies that appear not to exist in healthy people and could therefore be linked with the disease. Previous research had established that multiple sclerosis has a strong genetic component. ©independent.co.uk

Keyword: Multiple Sclerosis; Genes & Behavior
Link ID: 15664 - Posted: 08.11.2011

by Robert Krulwich OK, if you've got nothing else to do for one minute, let me mess with your head. Below, you will see two circles composed of parallelograms. There's a dot in the middle of the image. Focus on the dot. Move your head in, then move it out. Here is Pinna-Brelstaff Illusion. If you focus on the dot and move your head in, then move it out the circles spin. Weird, no? The circles seem to rotate. (Of course, they don't really rotate; if you focus on a single parallelogram, you can move your head in and out all day and that sucker won't move at all.) Something curious is going on. So I went to see an eye doctor (technically, he's a "visual science" professor, Ben Backus, at the State University of New York's College of Optometry) who agreed to explain to me why the circles seem to move. Yes, he said, what you are seeing is a lie ("illusion" is the polite word) but don't blame your lying eyes. Blame your lying brain. Copyright 2011 NPR

Keyword: Vision
Link ID: 15663 - Posted: 08.11.2011

By SINDYA N. BHANOO Male túngara frogs gather in shallow pools of water at night and let out long mating calls. Females visit these pools, listen to a few calls and then quickly pick mates. It’s a bit like speed dating. A male call consists of a whine followed by a series of grunts, or “chucks.” New research suggests that females judge males on these chucks — not the absolute number, but the ratio of one frog’s chucks to another. During the study in Panama, many female frogs seemed to prefer two chucks over a single chuck. But most did not show a preference between three chucks and two chucks. It’s a concept humans can relate to, said Karin Akre, an evolutionary biologist at the University of Texas at Austin who led the research. “If you have a pile of three oranges and four oranges, it’s pretty easy to see that one has more,” she said. “But it’s harder to tell the difference between 50 oranges versus 60 oranges, even though the absolute difference is greater.” The frogs are not alone at night; also lurking nearby are bats that prey on the frogs. Surprisingly, the researchers found that the bats use the same strategy as female frogs when selecting prey to single out. Like female frogs, they are drawn to males emitting more chucks, and make their determinations based on the ratio, rather than the absolute difference. © 2011 The New York Times Company

Keyword: Sexual Behavior; Hearing
Link ID: 15662 - Posted: 08.09.2011