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DURHAM, N.H. -- In a former cowshed on the edge of the University of New Hampshire campus, David Berlinsky, assistant professor of zoology, peers into a big blue plastic tub. Inside, black sea bass circle slowly in the dim light. The converted barn is now an aquaculture research facility for the College of Life Sciences and Agriculture, and home to Berlinsky’s latest research. Black sea bass feature prominently on many menus, but wild populations of the fish are in decline and their availability is limited. Because of the high demand, they’re a good candidate for aquaculture on the east coast. Except, that is, for one problem: they have a tendency to change sex unpredictably in captivity. “In the wild, black sea bass are born as females and turn into males at around two to five years old,” Berlinsky explains. “When you bring them into captivity, they change into males more quickly.” Some captive-born fish emerge as males even before reaching adulthood, devoting energy toward reproductive development and away from growth. Such problems make breeding and growing the fish in captivity a tricky proposition. “Black sea bass is a wonderful fish to culture and to eat,” says George Nardi, vice president and director of GreatBay Aquaculture, a commercial fish farm in Newington, NH. But the sex change problem must be tackled if fish farmers are to bring a high-quality fish to market. “We invest in our brood stocks, the parents of the young fish, much as a thoroughbred horse farm invests in mares and stallions,” he says. “It doesn’t do us much good if we always have to go out and get new females.”
Keyword: Sexual Behavior
Link ID: 8770 - Posted: 06.24.2010
Boston, MA – Researchers from the Harvard School of Public Health, Kaiser Permanente, and a team of collaborators have found further evidence implicating the Epstein-Barr virus (EBV) as a possible contributory cause to multiple sclerosis (MS). The study appears in the advance online edition of the June 2006 issue of Archives of Neurology. MS is a chronic degenerative disease of the central nervous system. Women are more likely than men to get the disease and it is the most common neurologically disabling disease in young adults. Although genetic predisposition plays an important role in determining susceptibility, past studies have shown that environmental factors are equally important. EBV is a herpes virus and one of the most common human viruses worldwide. Infection in early childhood is common and usually asymptomatic. Late age at infection, however, often causes infectious mononucleosis. In the U.S., upwards of 95% of adults are infected with the virus, but free of symptoms. EBV has been associated with some types of cancer and can cause serious complications when the immune system is suppressed, for example, in transplant recipients. There is no effective treatment for EBV. The study population was made up of more than 100,000 members of the Kaiser Permanente Northern California (KPNC) health plan, who provided blood specimens as part of medical examinations between 1965 and 1974.
Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 8769 - Posted: 06.24.2010
Adam Keiper Every so often, when some new scientific paper is published or new experiment revealed, the press pronounces the creation of the first bionic man—part human, part machine. Science fiction, they say, has become scientific reality; the age of cyborgs is finally here. Many of these stories are gross exaggerations. But something more is also afoot: There is legitimate scientific interest in the possibility of connecting brains and computers—from producing robotic limbs controlled directly by brain activity to altering memory and mood with implanted electrodes to the far-out prospect of becoming immortal by “uploading” our minds into machines. This area of inquiry has seen remarkable advances in recent years, many of them aimed at helping the severely disabled to replace lost functions. Yet public understanding of this research is shaped by sensationalistic and misleading coverage in the press; it is colored by decades of fantastical science fiction portrayals; and it is distorted by the utopian hopes of a small but vocal band of enthusiasts who desire to eliminate the boundaries between brains and machines as part of a larger “transhumanist” project. It is also an area of inquiry with a scientific past that reaches further back in history than we usually remember. To see the future of neuroelectronics, it makes sense to reconsider how the modern scientific understanding of the mind emerged.
Keyword: Robotics; Parkinsons
Link ID: 8768 - Posted: 06.24.2010
ANN ARBOR, Mich. -- It happens to all of us, no matter how hard we try. Whether it's deleting a computer file and realizing a split-second later that we can't get it back, or dropping a bag of groceries, or realizing that our gas tank is nearly empty on a lonely stretch of highway, we all make mistakes that aren't just annoying, but potentially costly. Now, a team of University of Michigan researchers has looked inside the human brain and captured the instant when someone makes a costly mistake. What they've found is interesting by itself, but may also help scientists understand mental health problems such as obsessive-compulsive disorder, or OCD. In general, the U-M scientists found that a particular part of the brain called the rostral anterior cingulate cortex, or rACC, becomes much more active when a person realizes he or she has made an error that carries consequences – for instance, losing money. By contrast, the same area of the brain doesn't show the same level of activity when the mistake doesn't carry a penalty, or even when a correct action carries a reward. The rACC is thought to be involved with emotional responses, and scientists had suspected it might also be involved in response to costly errors. But this is the first brain-imaging study to test that idea.
Keyword: Emotions; Brain imaging
Link ID: 8767 - Posted: 06.24.2010
By Jennifer Viegas, Discovery News — Labradors and dachshunds appear to waddle, while greyhounds seem to march by with a fast clip, but new research has determined that the basic mechanics behind dog walking are the same for all canines. The discovery could lead to a better understanding of health issues related to walking in dogs, such as hip problems. It could also result in improvements to four-legged, dog-like robots, which the U.S. military already is investigating. "The big benefit would be to show how robot dogs should walk more efficiently," said lead scientist Jim Usherwood, a researcher at the University of London's Royal Veterinary College Structure and Motion Laboratory. Usherwood added, "Almost all robots require a large amount of power — much higher than an animal would use — partly because they tend to use bent legs. I show what would happen with stiff legs." Inspired by stiff-legged mechanical toys that can walk down hills, Usherwood and his team designed several different computer models for dog walking. The researchers then compared these models with observations of actual dogs on a treadmill. © 2006 Discovery Communications Inc.
Keyword: Miscellaneous
Link ID: 8766 - Posted: 06.24.2010
Prashant Nair A strategy to reverse some of the brain changes triggered by cocaine, which lead to addiction, may have been uncovered by Swiss scientists. The findings constitute the first step in the development of a drug to reverse cocaine-driven rewiring in the brain, the researchers claim. Cocaine triggers changes in the brain that lead to the development of drug sensitisation – a learning-associated process that underlies addiction. Like many addictive drugs, cocaine ups the concentration of the brain chemical dopamine, causing neurons that respond to dopamine to fire. This process reorganises the brain circuitry and hardwires the addiction by disrupting the normal connections between two different brain regions. Those areas are the hippocampus and prefrontal cortex – associated with learning and memory – and the ventral tegmental area, involved with feelings of pleasure, reward and behavioural motivation (see "Cocaine use prevents adaptive behaviour"). But how cocaine drives this change in dopamine neurons was unclear until recently. Now, Christian Luescher and Camilla Bellone at the University of Geneva, Switzerland have shown that cocaine causes a switch in the components, or subunits, which make up the receptors on the surface of neurons in the ventral tegmental area, the brain’s "pleasure centre". This leads to excitatory wiring – or strong stimulation of these cells. Brain slices from mice given cocaine, showed the receptors in their brains had undergone a subunit switch. © Copyright Reed Business Information Ltd
Keyword: Drug Abuse
Link ID: 8765 - Posted: 06.24.2010
Snoring may run in families, a study by US scientists says. Researchers at Cincinnati Children's Hospital found children whose parents snore have a three-fold increased risk of being noisy sleepers themselves. But UK experts said the link was likely to be related to families being obese - half of snoring is related to weight. The study, based on interviews with 681 families and published in the Chest journal, also suggested a link between snoring and allergies. Researchers found children who tested positive for atopy, an earlier indicator for the development of asthma and allergies, were twice as likely to snore as those who did not. Parents were questioned about the extent to which both they and their children snored. Habitual snoring was reported in 15% of the children, and allergy sensitivity in 29%. Among the parents, 20% of mothers and 46% of fathers were habitual snorers. An increased risk of snoring occurred in 21.5% of children who were sensitive to allergy triggers compared with 13% of those who were not prone to allergies. The same trend was seen in 21.8% of children with a parental history of habitual snoring. Only 7.7% of children without a snoring parent turned out to be frequent snorers. The researchers said it was likely allergy-related respiratory diseases were causing the snoring. (C)BBC
Keyword: Sleep; Genes & Behavior
Link ID: 8764 - Posted: 04.11.2006
By JANE E. BRODY Americans' use of sleeping pills is skyrocketing, up nearly 60 percent since 2000, with about 42 million prescriptions filled last year. Experts surmise that "modern lifestyles" and the accompanying stress of too much to do in too little time are largely responsible for the growing need for the drugs. That may be true. But I see an altogether different explanation for the flagrant use of sleeping pills. In the last decade, there has been a sea change in the kinds of drugs available to induce sleep, and these drugs have been widely promoted in print and on television. You could hardly have missed that pale green luna moth (sans antennas) drifting over peaceful sleepers in ads for Lunesta, which has joined Ambien, Sonata and others in a new class of sleep aid. How tempting it is when people hear that, say, five milligrams of Ambien can temporarily sweep their worries under the mattress, allow them to fall asleep within 15 minutes and awaken the next morning refreshed and raring to go. I took it myself for several months last winter when the painful aftermath of knee replacements rendered a restful night's sleep impossible. Unfortunately, with the ease of writing and filling a prescription and the mostly good press these new drugs have gotten to date, millions of people are now taking them without first exploring the reasons for their sleep problems and possible nondrug routes to cure them. Copyright 2006 The New York Times Company
Keyword: Sleep
Link ID: 8763 - Posted: 04.11.2006
There is probably not a person alive on this planet who is immune to anxiety. As a psychiatrist, I'm often accustomed to thinking of anxiety as a symptom of a disorder like social phobia or major depression or as an aspect of normal everyday mental life. As unpleasant as anxiety can be, it is unlikely to represent a major threat, let alone kill someone — at least that's what I thought until I met my patient Mark. A 42-year-old man with a long history of anxiety and depression, Mark had made a remarkable recovery with medication and psychotherapy. Long after he'd been in remission from his depression, he came to see me about some financial problem that was upsetting him. Sure, he looked a bit anxious and troubled, but he was facing a real hardship, so a little anxiety seemed a perfectly reasonable, if not healthy, response to an unpleasant situation. But something about his appearance bothered me. He seemed ever so slightly short of breath and restless in his seat, something I'd never seen even in the throes of his worst anxious depressions. Copyright 2006 The New York Times Company
Keyword: Emotions
Link ID: 8762 - Posted: 06.24.2010
SAN DIEGO, — Cognitive impairment in people with AIDS exists in two forms -- one mild, another severe -- each affecting different areas of the brain, according to the results of a University of Pittsburgh School of Medicine study being presented today at the American Academy of Neurology 58th Annual Meeting in San Diego, Calif. The researchers say their findings indicate there probably are two separate mechanisms that can cause cognitive impairment in people with AIDS. “The advent of combination antiretroviral therapies to treat AIDS has significantly changed the course of the disease,” said James T. Becker, Ph.D., professor of psychiatry, neurology and psychology at the University of Pittsburgh. “Not only are people living longer with AIDS, but we are finding that a number of the other co-existing conditions that people with AIDS often experience are becoming less severe. Such is the case with cognitive impairment – we are finding less people have severe cases while more have milder forms.” Cognitive impairment in people with AIDS is caused when the HIV virus attacks the brain and can be a complicated syndrome resulting in deficits in mood, behavior, motor coordination and thought processes. Studies have shown that, especially since the advent of the first combination antiretroviral therapies, the incidence of severe dementia in people with AIDS has decreased significantly. However, AIDS-related dementia isn’t disappearing, and a greater number of people are living with a milder form of cognitive impairment.
Keyword: Miscellaneous
Link ID: 8761 - Posted: 06.24.2010
New Haven, Conn. -- Based on data obtained from one of the largest family sets of its kind, Yale School of Medicine researchers have identified a genetic linkage for dependence on drugs such as heroin, morphine and oxycontin. The lead author, Joel Gelernter, M.D., professor in the Department of Psychiatry, said the researchers recruited a sample of 393 small families, most with at least two individuals with opioid dependence. They then searched genetic signposts throughout the entire genome in an effort to identify markers that, within the same family, would show that individuals who share the illness also share marker alleles, or gene variants. This information allowed the team to identify where genes influencing opioid dependence are located. Gelernter said the researchers found evidence of gene linkage for opioid dependence. They also found strong evidence of linkage in the family groups for the symptom cluster traits characterized by dependence on substances other than opioids, specifically, alcohol, cocaine and tobacco. "These results provide a first basis to identify genes for opioid dependence from a genome-wide investigation," Gelernter said. "Research in the laboratory now is focused on finding specific genes that modify risk for opioid dependence."
Keyword: Drug Abuse; Genes & Behavior
Link ID: 8760 - Posted: 04.11.2006
Roxanne Khamsi The stimulating drugs known as amphetamines have a stronger effect on men than women, a new study reveals. The study is the first to reveal how the release of dopamine, an important nerve signalling chemical, differs between the sexes in humans, says Gary Wand of the Johns Hopkins University School of Medicine in Baltimore, Maryland, US. He says the findings could help researchers understand why some disorders such as Parkinson's disease and Tourette's syndrome more commonly afflict men than women. Research suggests that men are more prone to certain types of drug addictions. And according to a recent US health survey, 6.0% of males above the age of 12 illegally used amphetamines, also known as 'uppers', while only 3.8% of females did so. The new work showed amphetamines caused a greater surge of the pleasure-causing chemical dopamine in men than in women. "The fact that they responded differently to the drug suggests that there's an underlying biological sex difference in how the brain's reward centre responds to amphetamines," says Wand. The team recruited 43 healthy volunteers between the ages of 18 and 29 years of whom about a third were women. The participants did not have a history of drug abuse. The volunteers were given relatively low doses of amphetamines, and their dopamine response was measured with the help of a second chemical. © Copyright Reed Business Information Ltd.
Keyword: Drug Abuse; Sexual Behavior
Link ID: 8759 - Posted: 06.24.2010
Jacqueline Ruttimann People who have had near-death experiences are more likely to mix up dreams and reality than those who have not, researchers say. At times of extreme danger or trauma, many people report out-of-body experiences, seeing intense lights, or a feeling of peace. "Near-death experiences are more common than people realize," says neurophysiologist Kevin Nelson of the University of Kentucky, Lexington, lead author of the study published in Neurology1. Some studies have shown that electrical stimulation to the brain can trigger aspects of near-death experiences (see 'Electrodes trigger out-of-body experience'). Drugs can do the same: ketamine, a horse tranquilizer and illegal recreational drug, can cause many of these symptoms. But spontaneous near-death experiences remain unexplained. Nelson began investigating the phenomenon after reading of near-death experiences in which patients' arms and legs were paralysed. He knew that some people experience similar paralysis just before sleeping or just after waking. "A light bulb went on in my head," he says. Near death experiences are more common than people realize. ©2006 Nature Publishing Group
Keyword: Sleep
Link ID: 8758 - Posted: 06.24.2010
A failure in the chemical messaging system in the brain has been identified in people with schizophrenia. A team from the UK's Institute of Psychiatry compared hi-tech scans of the brains of people with the condition with healthy volunteers. They found a glitch at the chemical junction which needs to be negotiated for nerve cells to talk to each other. The charity Rethink said the research was important, but added schizophrenia was "more than a chemical imbalance". Schizophrenia affects around 1% of the population - as many as are affected by diabetes - and it often strikes young people as they aim to complete their education or begin work. It is linked to disrupted thinking and behaviour, but scientists want to discover why that happens. The IoP researchers, working with colleagues from University College London, used a scanning technique called single photon emission tomography (SPET). They compared brains in 13 healthy people with five people with untreated schizophrenia and another 16 who were on medication for the condition. When the communication system in the brain works properly, neurons talk to each other by sending out branches. These branches connect at a junction where the chemical glutamate acts as a key to unlock a barrier - a chemical called NDMA receptor - and allow the message through. A failure in this system leads to poor connections between areas of the brain that need to talk to each other. (C)BBC
Keyword: Schizophrenia
Link ID: 8757 - Posted: 04.10.2006
The difficulties people with autism have in relating to others could be due to poor communication between brain areas, scientists suggest. It may explain why they do not interact well, as the weak links mean they benefit less from social situations. It had been thought that their lack of social skills was due to abnormalities in particular brain areas. The study in Neuroimage, carried out by University of London researchers, compared brain scans of 32 people. The researchers took brain scans of 16 people with autism spectrum disorders (ASD) and above-average IQs, as well as those of 16 unaffected volunteers. They were shown four images on the screen - two of houses and two of faces. They were then asked to concentrate on either the faces or houses and decide if they were identical. Scans showed there were marked differences in the brain activity of the two groups. In the control group, paying attention to pictures of faces caused a significant increase in brain activity. But for people with ASD, paying attention to faces made no impact at all on the brain, explaining their lack of interest in faces. Both groups had the same reaction to houses. Dr Geoff Bird, at the UCL Institute of Cognitive Neuroscience, who led the research, said: "The standard view of social problems in ASD is that there is a problem in the part of the brain that processes faces. Our research suggests that this is not the real problem - it seems to be that paying attention to faces doesn't lead to the normal increase in brain activity. (C)BBC
Keyword: Autism
Link ID: 8756 - Posted: 04.10.2006
Nearly 1 in 7 adults in New York City described their mental health last year as being frequently "not good," compared with 1 in 10 adults in a comparable national survey, according to data being released today by the City Department of Health and Mental Hygiene. The findings, from the city's community health survey, a telephone poll of 10,000 randomly selected adults conducted each year since 2002, confirm what many New Yorkers suspect — that life in the nation's most populous city can be difficult and lonely. Thirteen percent of adults who answered the city's survey last year reported that their mental health was "not good" on 14 or more days of the month, compared with 10 percent in a similar national survey that measured "frequent mental distress," like stress, depression or other emotional problems. The data will be presented today in a conference at Hunter College organized by Dr. Neal L. Cohen, a former city health commissioner. Dr. Lloyd I. Sederer, the executive deputy commissioner for mental hygiene at the health department, said he believed that the higher rate of "frequent mental distress" reported by city residents was statistically significant, although the precise reasons were not clear. "I wish we knew, in a way that we could say with confidence, why that difference is," he said. Copyright 2006 The New York Times Company
Keyword: Stress; Depression
Link ID: 8755 - Posted: 06.24.2010
By Abby Christopher More than 50,000 people die of head injuries in the United States every year, according to the Centers for Disease Control and Prevention. But that number could be dramatically reduced if a new handheld brain scanner proves its mettle in the field. The InfraScanner, under development at Drexel University, could help medical teams detect brain injuries much more cheaply and quickly on the battlefield and at accident scenes. "How do you triage a soldier? How does an EMT figure out who to bring to a trauma center?" asked Dr. Geoff Manley, an associate professor of neurological surgery at the University of California at San Francisco Medical Center and neurotrauma chief at San Francisco General Hospital's trauma center. "A triage device is desperately needed. This device can help with early diagnosis, which reduces the chances of secondary injury," Manley said. The device, which consists of a scanner and a Windows-based PDA, uses patented near-infrared optical brain imaging to determine if there is bleeding in the brain. After scanning eight points on the head, the InfraScanner sends the data through a Bluetooth connection to the PDA, where it is displayed and stored. Results for each point scanned are coded green for no bleeding and red for bleeding. © Copyright 2006, Lycos, Inc.
Keyword: Brain imaging
Link ID: 8754 - Posted: 06.24.2010
By Susan Kruglinski In a recent issue of Discover, we wrote about people who use mnemonic skills to demonstrate incredible feats of memory (How to Win the World Memory Championship, April, 2006) Post press update: Our writer, Joshua Foer, actually won the event. Neuroscientists at the University of Irvine now claim to be studying a remarkable woman who is the first ever reported to have an extraordinary capacity for memory without using any mnemonic tricks – long ago memories simply pop into her head. Critics of this research wonder if she is not simply using ordinary memory skills in an unconscious way. In our June issue of Discover, we will have an article about this woman, who remains anonymous but is called AJ, and the controversial research. In the meantime, associate editor Susan Kruglinski has conducted an E-mail interview with AJ, asking her what it is like to remember every day as if it were yesterday. When and how did you realize you had superior memory skills? It was in 1978 when I was 12 years old. I was studying for my first set of finals at the end of the 7th grade and I was sitting and listening to my mother drone on and on about science and such, and I started to think about the year before when I was in the sixth grade, and how easy life was back then. It was May of 1978, so I started to think about that exact day back in May 1977, and I just started thinking about each day from that month the year before. It actually startled me at first to think that I could remember so exactly. What are you good at remembering? I can remember everything that has happened to me. What day it was on, what was happening in the world, who was in my life at the time, and usually what the weather was like. I am very affected by the weather, so it is always something I remember. If you were to tell me the day you were married or the day your child was born (in the last 30 years) I could tell you what day it was, what I was doing, etc. © 2005 Discover Media LLC.
Keyword: Learning & Memory
Link ID: 8753 - Posted: 06.24.2010
The discovery of a possible hibernation hormone in the brain may unlock the mystery behind the dormant state, researchers reported in the April 7, 2006 issue of Cell. Hibernation allows animals from bears to rodents to survive unscathed--in a state of suspended animation--under the harshest of winter conditions. If the findings in chipmunks are confirmed, the hormone would represent the first essential brain signal governing the seasonal adaptation, according to the researchers. As hibernation factors endow animals with an incredible ability to cope under otherwise lethal conditions--ratcheting down their metabolic rate to survive on limited energy reserves and withstanding extreme cardiovascular and oxygen stresses--the candidate hormone might also pave the way toward clinical therapies that lend humans the same kind of protection, they added. The researchers earlier found that concentrations of "hibernation-specific protein" complex (HPc) decline in the blood of hibernating chipmunks. The team now reports evidence that the level of HPc in the brain increases at the onset of hibernation independently of changes in body temperature. Moreover, treatments that block HP activity in the animals' brains cuts hibernation short.
Keyword: Biological Rhythms
Link ID: 8752 - Posted: 04.08.2006
A new skin patch may offer relief to patients in the early stages of Parkinson's disease. The Neupro patch, made by Schwarz Pharma, has been licensed for use in the UK. It delivers a drug that mimics the effects of a naturally occurring brain chemical, which is in short supply in people with Parkinson's. The Parkinson's Disease Society said the patch may help some manage their symptoms more easily. Between 8,000 and 10,000 new cases of Parkinson's are diagnosed in the UK every year, with 95% of cases in those aged over 40. At any one time, 120,000 people in the UK have the condition. People with the disease have a shortage of the brain chemical dopamine, which controls connections between nerve cells, leading to symptoms such as tremors. Until now, patients have mostly taken a dopamine agonist - an agent that acts directly on the dopamine receptors in the brain - in tablet form, or through injections of through a pump. The patch contains a new dopamine agonist, called rotigotine, and delivers a continuous dose of the drug over 24 hours, so patients only having to change the patch once a day. Doctors say it could help people who have problems swallowing pills and those with digestion problems that stop oral drugs being fully absorbed. (C)BBC
Keyword: Parkinsons
Link ID: 8751 - Posted: 04.08.2006


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