In a feat nowhere near as terrifying as the movie Jurassic Park, scientists have reconstructed a light-sensing protein from the ancestors of dinosaurs. It suggests that dinosaurs may have been well-adapted to seeing in the dark. Biologists are excited by the promise of the technique, which predicts the structure of proteins from extinct animals by studying those of living relatives--then brings the protein to life. Paleontologists learn about extinct animals in two main ways. They study fossils, and they make educated guesses based on existing creatures. Although neither method provides direct information about the molecular inner workings of the animals, inference is rapidly becoming more sophisticated. An intriguing prospect is the comparison of gene sequences to reconstruct molecules. But many scientists suspected this exercise would merely be computer-generated speculation. Now, molecular biologist Belinda Chang of Rockefeller University in New York City and colleagues have dispelled those doubts. Using the gene sequences that code for the visual protein rhodopsin in 30 living vertebrates, such as alligators, chickens, and more primitive vertebrates such as lampreys, the researchers reconstructed the rhodopsin belonging to the archosaurs. This ancient group gave rise to dinosaurs, as well as extant groups such as crocodiles and birds. Chang's team used a statistical method, known as maximum likelihood, that identifies the series of changes most likely to have generated the observed range of modern proteins and extrapolates the most likely common ancestor--the archosaur protein. Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Vision; Evolution
Link ID: 2579 - Posted: 06.24.2010

Parkinson's effects brain connections Researchers at Rutgers, The State University of New Jersey, have discovered critical clues that may explain why parts of the brain damaged by Parkinson's disease, specifically those that control sensory-guided movements, aren't repaired by dopamine replacement therapy. Parkinson's is the second most common neurodegenerative disease affecting older people in the United States and is characterized by a loss of dopamine in the basal ganglia portion of the brain. "Our research indicates that the loss of dopamine seems to cause connections in the brain to reorganize. This affects the brain's ability to communicate effectively with body parts, for example, the ability to respond to stimuli from the body in order to control body movements," explained Mark West, a behavioral neuroscientist and professor in the department of psychology at Rutgers' Faculty of Arts and Sciences-New Brunswick.

Keyword: Parkinsons
Link ID: 2578 - Posted: 09.04.2002

Obsessive-Compulsive Disorder (OCD) is a severe psychiatric condition affecting up to 3% of the general population lifetime. It is characterized by intrusive unwanted thoughts (obsessions) and the need to perform repetitive acts or rituals in order to alleviate the anxiety (compulsions). As an example, a patient who fears contamination would be afraid of touching anything and would feel that they must wash their hands over and over. The causes of OCD remain obscure. However, there is strong evidence for a genetic component (the risk of developing OCD is higher in the relatives of affected), and for the involvement of the serotonin (5HT) neurochemical system. Serotonin is a neurotransmitter that is essential for communication between cells, and it is possible that the receptors that tell how much serotonin should be released may be altered in OCD patients.

Keyword: OCD - Obsessive Compulsive Disorder; Genes & Behavior
Link ID: 2577 - Posted: 09.04.2002

Giving smokers medication to mimic an increase in their brain's level of a substance called dopamine could help squelch their desire for cigarettes, according to a new study. Researchers examined 20 heavy smokers who were given two drugs that either increased or decreased the brain's level of dopamine, a neurotransmitter that affects motor function. Dopamine, a chemical in the central nervous system, is believed to affect emotion, and research on animals has shown that nicotine causes a release of dopamine in brain areas that are associated with feelings of pleasure. Test subjects smoked less when given a drug that mimics the effects of dopamine in the brain than they did when given a second drug that impedes dopamine's effects. When the subjects were given the dopamine-mimicking drug, their desire to smoke dropped, but when the same smokers were given the dopamine-impeding drug, they took longer and more frequent puffs of smoke.

Keyword: Drug Abuse
Link ID: 2576 - Posted: 09.04.2002

By JANE E. BRODY Susan McGee of Bethesda, Md., and Jane Quinn of Brooklyn were not planning to take hormones at menopause. But after many months of sleep disrupted nightly by drenching sweats and changes of bedclothes, they gave in. Ms. McGee said she became so sleep deprived that she could hardly do her job and feared falling asleep while driving. Ms. Quinn found it increasingly difficult to concentrate on her work, became uncharacteristically irritable and began to think she was losing her mind. The hormones quickly restored their sleep and their sanity. These two are among millions of American women near, at or beyond menopause who are asking why so much remains unknown about a drug that has been on the market for 60 years, and what they should make of new findings that are surprising and disappointing proponents of hormone replacement therapy, or H.R.T. Copyright 2002 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 2575 - Posted: 09.03.2002

By SANDRA BLAKESLEE As hunting season approaches, people in Wisconsin and the Rocky Mountain states are increasingly worried about chronic wasting disease, the variant of mad cow disease that afflicts deer and elk. Scientists are fairly confident that no one in the United States has died from a human version of chronic wasting disease, but hunters are confused and frightened anyway. In Wisconsin in the past six months, 24 white tail deer have tested positive for the disease, and none of them looked sick. Not certain if venison frozen from last year's hunt is safe to eat, many families are throwing it away. Copyright 2002 The New York Times Company

Keyword: Prions
Link ID: 2574 - Posted: 09.03.2002

Some researchers believe that sleep helps learning By Harvey Black Most people require sleep to face tomorrow with a clear head. But clarity of mind may be just one reason why slumber is needed; a growing body of research suggests that sleep aids learning. It is a view not universally held, but supporting evidence appears to be growing. "We just don't know right now if it will turn out to be true. There is so much data coming out now," says Pierre Maquet, senior research associate, National Fund for Scientific Research, University of Liege, Belgium. "These data are coming from a wide variety of species, techniques, experimental paradigms. There is something behind it." Daniel Margoliash, professor of organismal biology and anatomy, University of Chicago, says, "A substantial percentage of the scientific population ... is still quite skeptical." Researchers have data supporting the link between sleep and memory from studies with humans, rats, and birds, in which the subjects perform numerous learning tasks.1 The studies focus on two specific parts of sleep--slow wave sleep (SWS) and rapid eye movement (REM) sleep. SWS is deep slumber marked by large-amplitude electroencephalogram (EEG) patterns. REM is characterized by high-frequency, low-amplitude EEGs and decreased muscle tone. These stages appear to have two different functions, says Robert Stickgold, assistant professor of psychiatry, Harvard Medical School. SWS strengthens memories or connections already in progress, but it does not help connect memories to one another. "I think REM sleep is going to turn out to be most relevant to ... associative and connective processes in memory," he says. A GOOD NIGHT'S LEARNING Matthew Wilson, associate professor in the Center for Learning and Memory at the Massachusetts Institute of Technology, studies the relationship between maze learning and sleep. He found that the hippocampus, a brain structure involved in spatial learning, appears to show the same activity pattern during sleep as when animals learn the maze.2 After research subjects awoke from SWS, their hippocampi retrieved recently acquired memory, Wilson says, witnessed at the level of patterns in the hippocampi's neurons. "One could describe what goes on in slow wave sleep as a replay of recent experience." ©2002, The Scientist Inc.

Keyword: Sleep; Learning & Memory
Link ID: 2573 - Posted: 06.24.2010

Pope John Paul II has been prescribed an experimental treatment made from a tropical fruit to ease symptoms of Parkinson's disease, it is reported. The French paper Le Monde reports that the treatment, an extract of fermented Asian papayas, was suggested by a French doctor, who met the 82-year-old Pontiff in June. Dr Luc Montagnier actually met the Pope to try to persuade him to relax the Catholic Church's stance on the use of condoms as a way to tackle Aids in the developing world. However, Dr Montagnier, who co-discovered the Aids virus, also used the meeting to propose the papaya treatment for the Pope, whose symptoms include a hand tremor and slurred speech. (C) BBC

Keyword: Parkinsons
Link ID: 2572 - Posted: 09.02.2002

The device may end the need for a skin prick test Scientists are developing a smart tattoo that could tell diabetics when their glucose levels are dangerously low. Once perfected, the tattoo will allow glucose levels to be monitored round the clock, and could allow an alarm system that would warn the diabetic if their glucose levels were to fall dangerously. It would also mean that diabetics would no longer have to subject themselves to the finger-stick devices that currently they must use every day. The tattoo has been designed Gerard Cote, of Texas A&M University, and Michael Pishko, of the chemical engineering department at Penn State University. It is made of polyethylene glycol beads that are coated with fluorescent molecules. Because glucose displaces the fluorescent molecules, the level of fluorescence is high when bodily glucose levels are low. Fluorescence levels could be measured using a device, such as a watch, that could also give users a readout of their glucose level. (C) BBC

Keyword: Obesity
Link ID: 2571 - Posted: 09.02.2002

By ANAHAD O'CONNOR Dr. Sanford L. Palay, a neuroscientist who helped uncover the detailed anatomy of the nerve cell and obtained the first images of the synapse and the structures that release messenger chemicals in the brain, died Aug. 5 at a hospital in Concord, Mass. He was 83. The cause was kidney failure, a family member said. In 1953, while conducting research at Rockefeller University in New York, Dr. Palay used the recently invented electron microscope to study the synaptic vesicles that transmit nerve impulses. His paper "The Fine Structure of Neurons" and his later research helped change thinking on nerve functions. Copyright 2002 The New York Times Company

Keyword: Evolution
Link ID: 2570 - Posted: 09.02.2002

A freak accident left Blake Harper paralyzed and bankrupt. But he vows to make a comeback. Mike Roberts The Province A few days after his first birthday in a wheelchair, 29-year-old Blake Harper will crawl into Okanagan Lake and attempt to swim a two-kilometre stretch of the lake's choppy waters. A sadder sight will not be seen on the lake that day -- a young man dragging his useless legs through the water while on the shore his friends cheer and his mom and sister sob for they don't know what: joy that he's so alive; sadness that he's so irreparably damaged. Before he joined the Spinal Cord Injury Club of Canada last spring (36,000 members and growing), Blake Harper was a strapping young carpenter, a natural bodybuilder who loved extreme sports, liked to travel and dreamed of one day opening his own scuba shop. © Copyright 2002 The Province

Keyword: Movement Disorders; Regeneration
Link ID: 2569 - Posted: 06.24.2010

LeRoy Hunter says in his family, falling down was a serious concern By Tyler Vincent, The Journal-Standard FREEPORT - Growing up with a mother afflicted with amyotrophic lateral sclerosis, or Lou Gehrig's disease, is bound to have an effect on a young man's outlook on life. Certainly that was the case for Freeport resident LeRoy Hunter, who reflects on those memories in his home office, in front of his walker that he has used for the last two years. Hunter, who was diagnosed with ALS in 1995, will be appearing on the Rockford edition of the Jerry Lewis Labor Day Muscular Dystrophy Association Telethon, which began Sunday night and runs through Labor Day. Copyright © 1995 - 2002 PowerOne Media, Inc. All Rights Reserved.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 2568 - Posted: 06.24.2010

A row has erupted after three experts suggested that Ecstasy may not be dangerous and that people are being misled about the drug. The psychologists have strongly criticised animal and human studies which say the drug causes long-term brain damage and mental problems. But other scientists insist the harmful effects of Ecstasy are undeniable. Writing in the magazine The Psychologist, published by the British Psychological Society, the researchers say the drug's reported adverse effects may even be imagined because of the belief that the drug causes long-term harm. © Copyright Press Association Ltd 2002, All Rights Reserved.

Keyword: Drug Abuse
Link ID: 2567 - Posted: 06.24.2010

by William Kanapaux Psychiatric Times August 2002 Vol. XIX Issue 8 Few topics have generated as much public concern as the diagnosis of attention-deficit/hyperactivity disorder (ADHD). According to data from the Centers for Disease Control and Prevention, outpatient visits for ADHD jumped from 1.6 million to 4.2 million per year from 1990 to 1993. More than 70% of those patients walked away with a prescription for Ritalin (methylphenidate). During the past decade, a growing body of research has reported that stimulant medications such as dextroamphetamine (Dexedrine, Adderall) and methylphenidate (Concerta, Methylin, Metadate) are safe and effective for treating ADHD. And the number of patients with ADHD continued to grow in the waiting rooms of pediatricians and family practitioners. Still, negative perceptions about ADHD diagnosis and treatment have been slow to change. This may be partially due to media outlets that raised alarms throughout the 1990s and 2000s about overdiagnosis and the dangers of treating children and adolescents with stimulants, which are schedule II drugs. © 2002 Psychiatric Times. All rights reserved.

Keyword: ADHD; Drug Abuse
Link ID: 2566 - Posted: 06.24.2010

Experimental spine surgery has enabled a paraplegic woman to walk again, a doctor has claimed. However, spinal experts are concerned about the ethics of the procedure, which they view as untested and highly controversial. Dr Giorgio Brunelli, of the Universita di Brescia, Italy, revealed details of the nerve-graft surgery at a conference in California. The woman's spinal cord was severed in a road accident. But Dr Brunelli said that following surgery she has regained limited use of her legs. In a 14-hour surgery performed in July 2000, Dr Brunelli removed a portion of the 28-year-old's sciatic nerve and used it as a graft to connect the undamaged portion of her spine to muscles in her buttocks and thighs. (C) BBC

Keyword: Regeneration; Development of the Brain
Link ID: 2565 - Posted: 08.31.2002

John Travis Since the mid-19th century, surgeons and their grateful patients have made use of ether and other general anesthetics. Yet exactly how these compounds produce a painfree, unconscious state remains mysterious. Now, scientists chipping away at the anatomical details have discovered that two of today's most common general anesthetics produce their sedative effects by triggering the brain's sleep circuits. Further research on the brain circuits affected by these anesthetics may lead to improved agents that generate an even more natural sleeplike state, say the biologists, who chronicle their research in an upcoming Nature Neuroscience. "The notion that anesthetics might somehow be recruiting a natural pathway that promotes sleep, as opposed to mucking up a pathway that keeps you awake," hasn't been considered seriously before, says study coauthor Nick P. Franks of the Imperial College School of Medicine in London. From Science News, Vol. 162, No. 9, Aug. 31, 2002, p. 132. Copyright ©2002 Science Service. All rights reserved.

Keyword: Sleep; Attention
Link ID: 2564 - Posted: 06.24.2010

If you want someone's attention, show them the money and you're more likely to get results, at least when it comes to their body's responses, a new study suggests. The study found that subjects showed different physical responses to loud noises when they were being paid to keep track of tones that were interrupted by those noises, says author Larry W. Hawk Jr., Ph.D., of the State University of New York at Buffalo, writing in the September issue of the journal Psychophysiology. The researchers recruited 43 college students, all of whom received college credit in exchange for participating in the study. But one group of 22 students received up to $5 each, depending on how well they performed on a task, while the other group of 21 students was simply told, "For the information that we collect from you to be useful, it's crucial that you try your best." Each participant was put into a soundproof booth and given headphones. Electrodes measured the size and strength of each subject's blinks as a response to a loud noise, giving an indication of how closely the student was paying attention. The subjects then listened to a series of tones and were asked to count the number of longer-than-usual tones that were played in a particular pitch, while ignoring tones in a different pitch.

Keyword: Attention; Hearing
Link ID: 2563 - Posted: 08.31.2002

Durham, N.C. -- People with severe mental illnesses are highly unlikely to become violent toward others unless they have additional risk factors combined with their psychiatric disorder, according to a new study led by researchers at Duke University Medical Center. Among people with severe mental illness, a combination of three risk factors -- having been a victim of violence during childhood, living in a neighborhood where violence is common, and having a substance abuse problem -- can increase the likelihood of violent behavior more than tenfold, the researchers found. Without any of these risk factors, those with severe mental illness were no more likely to engage in violent behaviors than people in the general population without a psychiatric disorder. “Acts of violence by people with mental illness are rare,” said Jeffrey Swanson, Ph.D., associate professor of psychiatry and behavioral sciences, a sociologist at Duke and lead author of the study. “While the illness certainly plays a role, the risk factors we examined compound the illness in a way that makes violence more probable. Those risk factors should be a large part of the focus of treatment and services for persons with mental illness and a history of violence.” © 2001-2002 Duke University Medical Center. All Rights Reserved.

Keyword: Schizophrenia; Aggression
Link ID: 2562 - Posted: 06.24.2010

Copyright © 2002 AP Online By ANDREW BRIDGES, AP Science Writer LOS ANGELES - An experimental nerve-graft surgery allowed a paraplegic woman whose spinal cord was severed in an automobile accident to reacquire limited use of her legs, an Italian doctor reported this week at a conference in California. In a 14-hour surgery performed in July 2000, Dr. Giorgio Brunelli, of the Universita' di Brescia, Italy, removed a portion of the 28-year-old's sciatic nerve and used it as a graft to connect the undamaged portion of her spine to muscles in her buttocks and thighs. He said the graft allowed the regrowth of nerves connected to the central nervous system into the muscle tissue. The unidentified patient first showed movement in her legs in September and since has begun walking with assistance, Brunelli said. The woman had used a wheelchair for five years prior to the surgery. Copyright © 2001 Nando Media

Keyword: Regeneration
Link ID: 2561 - Posted: 06.24.2010

By Mark Baard Instead of counting sheep, insomniacs may find relief listening to the sounds of their own brain waves. Results of a University of Toronto study indicate that "brain music" -- EEG recordings converted into musical compositions in a computerized process -- sends sleepless patients to dreamland faster. A two-minute recording ( [audio] hear audio excerpt) of one insomniac's brain music sounds a bit like a Brian Eno composition. Copyright © 1994-2002 Wired Digital Inc. All rights reserved.

Keyword: Sleep
Link ID: 2560 - Posted: 06.24.2010