Roxanne Khamsi Can a drink a day prevent mental decline? The finding that older women who consume moderate amounts of alcohol score better on cognitive tests suggests that it can. An investigation has revealed for the first time that the brain can benefit from consumption of both beer and wine. In the early 1990s, researchers often referred to the 'French paradox' to support the idea that wine promotes good health1. The phrase refers to the fact that French people have a lower risk of heart attack than Americans do, even though their diets contain similar levels of fat. More recent studies have also linked modest beer consumption with a decreased risk in heart disease2. But although researchers know that moderate drinking benefits the heart, there haven't been any significant studies of whether moderate alcohol intake has any effect on the brain. ©2005 Nature Publishing Group

Keyword: Drug Abuse; Multiple Sclerosis
Link ID: 6727 - Posted: 06.24.2010

Harbour porpoises are being killed in increasing numbers by bottlenose dolphins around British coasts, possibly due to competition for food. The evidence comes from counts of porpoises washed up on coasts and from post-mortem examination of the animals. A lack of fish may be turning the dolphins on their cetacean relatives, according to some scientists. The findings, from researchers based at London's Natural History Museum, appear in BBC Wildlife magazine. Acting on their own, or with others, bottlenose dolphins ram the porpoises with their beaks, causing multiple injuries that include internal bleeding, rib fractures, ruptured lungs dislocated spines. The porpoises are less than two-thirds the size of the dolphins. Annual reports show a steady rise in the number of porpoise strandings, with 40 in 1995 and more than 120 in 2004. Most of the strandings in the study occurred on the Welsh coast. Post-mortem examinations reveal that of those 120, nearly three quarters were killed by bottlenose dolphins. This represents a three-fold increase in four years, according to the Strandings Co-ordination Group which is based at the Natural History Museum. Rod Penrose, a spokesman for the group commented: "A decline in harbour porpoise bycatch over the years in Wales has been replaced by this violent interaction between these two species. (C)BBC

Keyword: Aggression
Link ID: 6726 - Posted: 01.20.2005

Could the new weapon in the battle of the bulge be a nasal spray? Scientists are looking into a spray containing a naturally-occurring hormone, PYY3-36, which may tell the brain that the belly is full. In 2002, researchers from Imperial College in London discovered that the gastrointestinal hormone PYY3-36 appears to signal to the brain that the stomach is full. Steve Bloom, a researcher at Hammersmith Hospital and professor at Imperial College, reported it reduced food intake and body weight in rodents, and in a small study in humans. However, 42 scientists from 12 different labs around the world independently tested PYY3-36 in rodents and failed to see the same results, finding no significant effect on food intake or body weight. But now, a round of tests on rats by researchers at Creighton University School of Medicine and the Omaha Nebraska VA hospital is showing more positive results. "We now, I think, have clearly shown that PYY3-36 is a potent inhibitor of food intake," says Roger Reidelberger, professor of biomedical science at Creighton University. In the other studies, scientists used shots—either a placebo or the real thing—to deliver the hormone, causing Bloom and other scientists to suggest that if the rodents weren't properly adapted to being handled and injected, it may have stressed out the rodents and affected the results. Reidelberger reported in the journal Endocrinology that in the tests he and his team did, the hormone was delivered intravenously, to get a steady flow of lower doses."By infusing it like we do, over a period of hours, we can maintain the levels, much like what occurs under normal conditions after ingesting a meal," Reidelberger explains. © ScienCentral, 2000- 2005

Keyword: Obesity
Link ID: 6725 - Posted: 06.24.2010

Attention Deficit Hyperactivity Disorder (ADHD) affects three to five percent of all children, perhaps as many as two million American children, and two to three times more boys than girls. The most common ADHD behaviors fall into three categories: inattention, hyperactivity, and impulsivity; people with ADHD can have trouble with things like sitting still and focusing on tasks. In many cases, medications such as Ritalin are prescribed to children with ADHD. "They're kids who have difficulty at school, who have difficulty at home," explains Manzar Ashtari, professor of radiology and psychiatry at North Shore-Long Island Jewish Health System, who has studied ADHD in children for twenty years. "They're constantly fidgety, they lose things, they forget things, and they're very disruptive in their behavior and this will make them very lonely because they usually have no friends, and socially, basically, they are suffering, and that basically causes the parents to suffer as well." While ADHD is typically described as a chemical imbalance, Ashtari says she may have found a clue that helps explain physical differences in ADHD children's brains. Building on previous research on brain abnormalities in ADHD kids, Ashtari chose a new MRI-based technique called diffusion tensor imaging (DTI) to look at the white matter (which is composed of nerve fibers) in children's brains in more detail. DTI tracks water motion along the fibers that connect brain parts and transmit and receive information. After scanning 18 ADHD-diagnosed kids and 15 children without ADHD, she compared the structure and function of fibers in each group's brains, and found that "the motion of the water, the way it should be in normal controls, is not in ADHD kids." © ScienCentral, 2000- 2005. All rights reserved.

Keyword: ADHD
Link ID: 6724 - Posted: 06.24.2010

ST. LOUIS -- If you're a middle-aged guy who's packed on the pounds and now is battling to take them off, it's a 50-50 shot that your jeans are fitting tighter because of your genes, according to a Saint Louis University School of Public Health study. "About 50 percent of adult onset weight change remains genetic," says James C. Romeis, Ph.D., professor of health services research at Saint Louis University School of Public Health and the principal investigator of the study, which was published in a recent issue of Twin Research. Romeis studied sets of twins who served in the military during the Vietnam War –some identical (who share the same genes) and some fraternal (who share half their genes) – and found that genes account for more than 50 percent of the change in Body Mass Index. How we deal with our environment – what we eat, the amount we eat and how much we exercise – accounts for the other 50 percent. It's tough enough for Joe Six Pack to take off weight. But for those whose genes predispose them to be heavy, weight loss is going to be difficult – really difficult – and take extra effort.

Keyword: Obesity; Genes & Behavior
Link ID: 6723 - Posted: 06.24.2010

Transcranial magnetic stimulation (TMS), in which the brain is stimulated using a magnetic coil held outside the skull, has shown some promise in both studying the brain and in treating mental disorders such as depression, epilepsy, and Parkinson's disease. Such magnetic fields induce tiny electrical currents inside the skull that alter the activity of neural pathways. While TMS offers the advantages of relative safety and noninvasiveness, the results of its use in both research and treatment have been disappointing. In human studies, neurological effects of TMS have been transient, rarely lasting longer than 30 minutes. Now, researchers led by John Rothwell of the Institute of Neurology at University College London have devised a new TMS method that produces rapid, consistent, and controllable changes in the motor cortex of humans that last more than an hour. Their findings offer the potential for both more useful research studies using TMS as well as greater therapeutic application. In their studies, the researchers applied various patterns of repetitive magnetic pulses to the scalps of volunteer subjects. They aimed the pulses at the motor cortex that controls muscle response, because effects on the motor cortex can be objectively measured by recording the amount of electrical muscle response to stimulation. Specifically, the researchers positioned the magnetic coil over the motor cortex area that controls hand movement, and they measured response by determining the amount of muscle response in a small muscle in the subjects' hands.

Keyword: Miscellaneous
Link ID: 6722 - Posted: 01.20.2005

Jessica Ebert Cuttlefish may be the most talented quick-change artists in the animal kingdom. Single males can adopt a sophisticated feminine disguise to help them get near females that are guarded by large males. Now researchers have proved that the mimics, who can change their appearance instantaneously, are successfully mating with such females. Each year, during the winter, thousands of giant Australian cuttlefish (Sepia apama) gather on the southern coast of the continent to mate. The competition between males for the females is intense. On average, four males fight over each female, but the ratio can be as high as eleven to one. The winner of each challenge, usually a large male, guards his mate closely. But smaller males still manage to secure about a third of all matings. There is a range of tactics from which a 'sneaker' male can choose. The options include waiting until the consort male is busy fending off a challenge; meeting his mate under a rock as she prepares to lay an egg; and disguising oneself as an female. ©2005 Nature Publishing Group

Keyword: Sexual Behavior
Link ID: 6721 - Posted: 06.24.2010

Scientists say they now know more about what happens in the brains of former drug addicts when they crave cocaine. Tests on rats by US National Institute on Drug Abuse researchers found a way of blocking craving messages in their brains and preventing a relapse. Nature Neuroscience says the findings suggest the danger time is not straight after addicts stop taking the drug, but after they go long periods without it. The study found a protein in the brain plays a part in triggering cravings. In their study, the team trained rats to press a lever to receive an intravenous injection of cocaine. The rats were also trained to associate certain cues, such as a light, with the availability of the drug. Once this behaviour pattern was established, the researchers withheld both cocaine and cues associated with the drug from the rats for a month. When the rats were again exposed to the cues after 30 days of withdrawal, they showed much higher levels of craving than they did after just one day. When the researchers examined the rats, they looked at the activation of a protein called extracellular-signal regulated kinase (ERK) in the amygdala, a part of the brain involved in motivation and emotion. (C)BBC

Keyword: Drug Abuse
Link ID: 6720 - Posted: 01.19.2005

DISCOVER, FEBRUARY 2005 If you want to find alien life-forms, hold off on booking that trip to the moons of Saturn. You may only need to catch a plane to East Lansing, Michigan. The aliens of East Lansing are not made of carbon and water. They have no DNA. Billions of them are quietly colonizing a cluster of 200computers in the basement of the Plant and Soil Sciences building at Michigan State University. To peer into their world, however, you have to walk a few blocks west on Wilson Road to the engineering department and visit the Digital Evolution Laboratory. Here you'll find a crew of computer scientists, biologists, and even a philosopher or two gazing at computer monitors, watching the evolution of bizarre new life-forms. These are digital organisms-strings of commands-akin to computer viruses. Each organism can produce tens of thousands of copies of itself within a matter of minutes. Unlike computer viruses, however, they are made up of digital bits that can mutate in much the same way DNA mutates. A software program called Avida allows researchers to track the birth, life, and death of generation after generation of the digital organisms by scanning columns of numbers that pour down a computer screen like waterfalls. After more than a decade of development, Avida's digital organisms are now getting close to fulfilling the definition of biological life. “More and more of the features that biologists have said were necessary for life we can check off,” says Robert Pennock, a philosopher at Michigan State and a member of the Avida team. “Does this, does that, does this. Metabolism? Maybe not quite yet, but getting pretty close.” Copyright 2004 Carl Zimmer

Keyword: Evolution
Link ID: 6719 - Posted: 06.24.2010

Hypnosis has been misunderstood as a nightclub stunt, a loss of control and a type of sleep, but it's been a therapeutic tool for centuries. Dr. David Spiegel, associate chair of psychiatry and behavioral sciences at Stanford University School of Medicine describes hypnosis as a "focused state of attention." "Being hypnotized is something like looking through a telephoto lens," Spiegel explains. "What you see you see with great detail, but you're less aware of the surroundings, of the context in which you're experiencing it. So it's like getting so caught up in a good movie that you forget you're watching the movie, you enter the imagined world. That's what a hypnotic state is like. You wake up and pay attention in a highly focused way. So the parts of the brain that are involved in attention, the frontal cortex, for example, are turned on when you're hypnotized." Spiegel uses hypnosis—specifically, he teaches self-hypnosis—to help adults and children control their pain and anxiety during certain surgical procedures. He taught a self-hypnosis technique to 23 children aged four to 15 who had to undergo a stressful medical test called a voiding cystourethrography. He reported in the journal Pediatrics that they showed less distress, and the test was easier to conduct, and took nearly a third less time, compared to 21 children who underwent routine treatment. "In the last five years we've begun doing randomized trials for acute surgical and medical pain," he says, "and we've got a number a studies now that show that hypnosis reduces pain, reduces anxiety, reduces the amount of medication people need, reduces complications, and makes the procedures shorter, 17 to 20 minutes per procedure." © ScienCentral, 2000- 2005.

Keyword: Pain & Touch
Link ID: 6718 - Posted: 06.24.2010

New research published in the premier issue of Cell Metabolism finds that a single brain region is sufficient for normal control of blood sugar and activity level by the fat hormone leptin. The same region also exerts significant, though more modest, control over leptin's effects on body weight. The findings in mice provide insight into potential mechanisms underlying type II diabetes and suggest new avenues for treatment, according to the researchers. Secreted by fat cells, leptin signals the status of the body's energy content to the brain and is required for normal body weight and glucose balance. Mice lacking leptin develop obesity, diabetes, and inactivity, among other symptoms. The new results suggest that leptin signaling acts directly on the brain region known as the hypothalamic arcuate nucleus (ARH) to control insulin and glucose levels in the bloodstream, report Joel Elmquist and Bradford Lowell, both of Beth Israel Deaconess Medical Center and Harvard Medical School, and their colleagues. ARH neurons also mediate the majority, if not all, of the hormone's action on locomotor activity, they found. Leptin receptors in the ARH accounted for approximately 22 percent of the hormone's effects on body weight, the group reports, suggesting that other brain regions are also important to this hormonal function.

Keyword: Obesity
Link ID: 6717 - Posted: 01.19.2005

UCLA/VA scientists have identified a new gene that controls how the body produces and uses fat. Called lipin, the gene may provide a new target for therapies to control obesity, diabetes and other weight-related disorders. The first issue of the new journal Cell Metabolism publishes the findings in its January 2005 edition. "Lipin regulates how the body stores and burns fat. Our findings suggest that differences in lipin levels may play a role in why some people are more prone to weight gain than others who consume the same calories," said principal investigator Karen Reue, Ph.D., a professor of medicine and human genetics at the David Geffen School of Medicine at UCLA and a researcher at the Veterans Affairs Greater Los Angeles Healthcare System. In 2001, Reue's laboratory was the first to isolate the lipin gene and link it to lipodystrophy, a wasting disorder in which the body is unable to produce fat. She also found that too little lipin prevented both genetic and diet-related obesity. For this study, Reue and coauthor Jack Phan, Ph.D., tested whether too much lipin would produce the opposite effect. Her team developed animal models using two sets of specially bred mice. Each group had a genetic mutation that boosted the level of lipin – one group in their fat tissue and the other group in their muscles.

Keyword: Obesity
Link ID: 6716 - Posted: 06.24.2010

A naturally occurring hallucinogen advocated by some clinicians as a potent anti-addiction drug has been rigorously studied for the first time, confirming its ability to block alcohol craving in rodents, and clarifying how it works in the brain. The new research findings about the drug Ibogaine open the way for development of other drugs to reverse addiction without Ibogaine's side effects, potentially adding to the small arsenal of drugs that effectively combat addiction. Derived from a West African shrub, Ibogaine has been championed for years by a cadre of clinicians and drug treatment advocates impressed with its ability to reverse withdrawal symptoms and craving for alcohol and various drugs of abuse. It has been used outside of the U.S. to treat addiction by American and other clinicians. But its side effects, including hallucinations, which made it popular in the 1960s drug culture, and evidence of toxicity to certain nerve cells in rodent studies have discouraged careful studies of its clinical potential against drug and alcohol addiction. The FDA has not approved use of Ibogaine in the U.S. Scientists at UCSF's Ernest Gallo Clinic and Research Center have now shown definitively in experiments with mice and rats that Ibogaine does reduce alcohol consumption, and they have determined that it does so by increasing the level of a brain protein known as glial cell line-derived neurotrophic factor, or GDNF. In a separate study, they demonstrated that GDNF by itself decreases alcohol consumption.

Keyword: Drug Abuse
Link ID: 6715 - Posted: 01.19.2005

By JANE E. BRODY A woman who lived for years in my neighborhood periodically appeared at a window and shouted obscenities into the street. Passers-by were appalled, but I felt what had to be the painful humiliation of someone who had no ability to control this seemingly antisocial behavior. I realized that the woman was afflicted with Tourette's syndrome, a lifelong neurological disorder with symptoms that contrary to popular belief, only rarely include the involuntary shouting of obscenities. I now know that the disorder is associated with a wide range of confusing symptoms that often result in delays in diagnosis and treatment that can last years. The problem was eloquently described in a two-part article last August in Contemporary Pediatrics. In his report, Dr. Samuel H. Zinner, a pediatrician at the University of Washington specializing in developmental and behavioral problems, points out that the syndrome "often goes undiagnosed or misdiagnosed." "Misconceptions about this tic disorder are customary," he adds, "with the syndrome often perceived as characterized by bizarre, fitful behaviors or comical outbursts of uncontrollable profanity." Copyright 2005 The New York Times Company

Keyword: Tourettes
Link ID: 6714 - Posted: 01.18.2005

By HENRY FOUNTAIN Homing pigeons are renowned for their ability to navigate over long distances, and after decades of study scientists are pretty sure they know how the birds do it. They use their sense of smell to figure out where they are and the position of the sun to determine the direction they must fly. But less is known about how pigeons navigate when they are close to home, in more familiar surroundings. Many researchers have thought that in such situations the birds must rely, at least partly, on visual cues. "There's been controversy about whether familiar landmarks have been used," said Jessica Meade, a doctoral student in the Animal Behavior Research Group at the University of Oxford in England. "Because there was no tracking of the birds along the homeward route, the hypotheses aren't very clear." Ms. Meade and two colleagues, Dr. Dora Biro and Dr. Tim Guilford, set out to rectify that situation, using small Global Positioning System loggers attached to the backs of 15 homing pigeons. These devices, which weigh about an ounce, use satellite signals to record precise location fixes every second. The researchers released the birds about three miles from home, and each bird had about 20 flights from the same point. The results are published in Proceedings B, a journal of the Royal Society. Copyright 2005 The New York Times Company

Keyword: Animal Migration
Link ID: 6713 - Posted: 01.18.2005

By KEITH HUMPHREYS and SALLY SATEL How should we set priorities in medical research? Officials at the National Institutes of Health will grapple with this question as they allocate billions of dollars from the agency's budget this year. Two geneticists, Dr. Kathleen Merikangas of the National Institute of Mental Health and Dr. Neil Risch of Stanford University, have taken on this challenge by introducing an intriguing framework for setting priorities for genetic research. The best candidates for genetic research, they believe, are disorders whose emergence and course cannot be derailed by changes in personal habits or manipulation of the environment. Examples are autism, Type 1 diabetes and Alzheimer's disease. In contrast, lower priority on the genetic research hierarchy should go to conditions like Type 2 diabetes or alcohol or nicotine addiction, they argue. Type 2 diabetes, after all, can be largely avoided through exercise and weight loss, and teenagers will buy less beer if taxes on alcohol are high enough. Similarly, a combination of smoking bans, social pressure and taxes have had an impact on smoking. Not surprisingly, the geneticists' proposal, published in Science, drew fire from their colleagues who study addiction, including Dr. Nora Volkow, director of the National Institute on Drug Abuse. In a published rebuttal last June, they insisted that addiction deserved a much higher ranking for genetic-research money, noting that the health and social costs of alcohol and drug addiction exceed $500 billion a year. Copyright 2005 The New York Times Company

Keyword: Genes & Behavior; Drug Abuse
Link ID: 6712 - Posted: 01.18.2005

Carl T. Hall, Chronicle Science Writer Dr. Richard Olney, a San Francisco neurologist and pioneer in ALS research, has launched an ambitious clinical trial testing whether two established drugs used in AIDS and cancer might also help some ALS patients. It's a trial that Olney designed and expected to lead as head of a specialized clinic at UCSF for people with ALS, or amyotrophic lateral sclerosis, popularly known as Lou Gehrig's disease. Those plans have changed. For this trial, Olney is participating not as a doctor, but as one of 60 patients. In fact, he made it a point to be the first one to sign up. He went through the initial round of evaluations last week. He expects to be given either the AIDS drug, a protease inhibitor called ritonavir; or the cancer drug, hydroxyurea; or a placebo, starting in about two weeks. Olney, 56, is regarded to be among the country's top clinical investigators of ALS, having spent most of his career conducting trials and working with patients. In June, he was diagnosed with the same disease he has spent a lifetime studying. It's a twist of fate that has shocked the close-knit ALS world. The case also underscores the challenges posed by one of the deadliest -- and fastest- moving -- disorders of the nervous system. ©2005 San Francisco Chronicle

Keyword: ALS-Lou Gehrig's Disease
Link ID: 6711 - Posted: 06.24.2010

INDIANAPOLIS – A mutation in a recently discovered Parkinson's disease gene is believed to be the most common genetic cause of inherited forms of the disease, according to a Parkinson Study Group study appearing in The Lancet in January. Researchers say the mutation on the LRRK2 gene is responsible for 5 percent of inherited Parkinson's disease cases. Tatiana Foroud, Ph.D., associate professor of medical and molecular genetics at Indiana University School of Medicine and principal investigator on the multi-site study, said the discovery has a broad implication for genetic screening for the disease. "Our results suggest that the mutation we have studied is the most common cause of Parkinson's disease identified to date," said Dr. Foroud. "While a great deal of work remains to be done, it is clear that any future genetic testing for Parkinson's disease must include studies of the LRRK2 gene." The patients in the Indiana University study who had the mutation had longer disease duration but less severe symptoms when they were participating in the trial. That suggests that the mutation may be associated with slower disease progression, said Dr. Foroud.

Keyword: Parkinsons; Genes & Behavior
Link ID: 6710 - Posted: 06.24.2010

Mothers who are more mature tend to display more affection towards their infants whereas teenage mothers often focus on instrumental behaviour – fixing their infant’s clothes or their soother – finds a new study of maternal behaviour. “While the study is still preliminary, this finding was very surprising,” says Katherine Krpan, lead author of the study, conducted as part of her undergraduate thesis at U of T at Mississauga (UTM). She is currently a PhD student in psychology at U of T. “We expected to see teen mothers exhibit more inappropriate behaviours towards their babies such as poking and prodding, which has been shown by previous research. Instead, they were behaving appropriately but displayed more instrumental behaviour and less affection compared to the adult moms.” Krpan, along with her co-authors Alison Fleming, Rosemarie Coombs and Dawn Zinga from UTM and Meir Steiner from McMaster University and St. Joseph’s Healthcare, examined the maternal behaviour of 119 mothers in three age groups – teenage mothers (15 to 18 years), young mothers (19 to 25 years) and mature mothers (26 to 40 years), all of whom had given birth within a three-month time span. They were drawn from the Hamilton area at either hospitals or institutions that provide post-natal care. The researchers also analyzed how the mothers’ maternal responses related to their hormonal levels and early childhood experiences. All contents copyright ©2004, University of Toronto.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 6709 - Posted: 06.24.2010

The first biological test for attention-deficit hyperactivity disorder has been developed. The researchers claim the diagnosis, based on examination of eye movements, is more than 93% accurate and could lead to earlier identification and treatment for children with the condition. Scientists analysed the eye movements of 65 children aged between four and six in Thessaloniki, Greece. About half of the children had been diagnosed as having ADHD through the standard method of psychological assessment and the use of questionnaires. The children were placed in front of a computer screen while wearing special goggles to monitor their eye movements and asked to use their eyes to "lock-on to" and follow spots of light that traversed the screen during a 10-minute test. "Children with ADHD show large difference in eye movements compared with normal children. For example, those without ADHD could follow the light spot for 30 seconds to as much as five minutes, whereas the children with the disorder could only follow the stimulus for about three to five seconds," says Giorgos Pavlidis at University of Brunel, UK, who led the study. The group analysed eye movements according to various criteria, these included fixation on the stimulus, saccades - jerking between two focal points - and smooth pursuit. The computer was able to correctly diagnose 93.1% of the children. © Copyright Reed Business Information Ltd.

Keyword: ADHD
Link ID: 6708 - Posted: 06.24.2010