by Apoorva Mandavilli, BioMedNet News Doubts about the identity of a key enzyme implicated in Alzheimer's disease (AD), which many researchers thought were resolved, surfaced this afternoon when one of the field's leading experts criticized development of inhibitors to the enzyme, gamma-secretase, as a potential therapy. Assuming that the protein presenilin is gamma-secretase, in the face of results to the contrary, is like relying on "three blind men describing an elephant," Peter St George-Hyslop told BioMedNet News. Gamma-secretase enzyme is central in generating beta-amyloid fragments, which are implicated in AD. Several teams have isolated the enzyme's activity to a high molecular weight complex that has several unidentified components. Over the past few years, some high-profile researchers, including Harvard's Dennis Selkoe, have proposed that presenilin 1 (PS1), a member of the complex, is itself the elusive gamma-secretase. © Elsevier Science Limited 2002

Keyword: Alzheimers
Link ID: 2046 - Posted: 06.24.2010

Children in a close and loving relationship with their mothers and who have a supportive family life are less likely to become involved in drug or alcohol abuse, a study claims. Child psychiatrist Dr Paul McArdle, at Newcastle University, headed the survey of 4,000 youngsters across Europe which concludes "attachment, particularly to mothers, is a potent inhibitor and that this is true across cultures and substances". The study reveals 14 and 15-year-olds living with both parents in a well supervised and loving atmosphere are less likely to have drug and alcohol habits. Of those without parents at home and without a supportive and supervised homelife, 42% were likely to be involved in drugs but if both factors are present, the figure falls to 17%. (C) BBC

Keyword: Drug Abuse
Link ID: 2045 - Posted: 05.10.2002

MANHATTAN -- We've all known what it's like to have the blues. Depression and anger can make you sick, literally. But a new study at Kansas State University shows that some people take longer to snap out of it -- which can lead to health problems -- while cheerful people tend to stay happy longer. Psychologists have known for a while that some people experience emotions more intensely than others. But little was known about how people differ in the amount of time they experience an emotion before it fades away, said Scott Hemenover, an assistant professor of psychology at K-State. In the past, neurotic people were defined by how strongly they felt depressed or angry, not how long those emotions lasted. Likewise, extroverts were defined by how strongly they felt happy, not how long they felt happy. Extroverts are also associated with sociability and the desire to seek excitement.

Keyword: Depression; Stress
Link ID: 2044 - Posted: 05.10.2002

Researchers present theory of memory and memory loss (Little Rock) Findings published last week in Proceeding of the National Academy of Science (USA) could lead to a better understanding of how our memory changes with age, according to John Hart, Jr., M.D. associate professor in the Reynolds Department of Geriatrics of the UAMS College of Medicine and a co-author of the study. "This new approach to looking at mechanisms of memory via electrical rhythms raises a whole series of questions about how the brain operates and what happens when it doesn't work properly," he explained. The study, conducted by Dr. Hart and co-investigators Scott Slotnick, Ph.D., Lauren Moo, M.D., Michael Kraut, M.D., Ph.D., and R. Lesser, M.D. of Johns Hopkins University, involves a novel explanation for how we recall memories for objects that surround us. The medical researchers suggest that objects occur in your memory by uniting together the different brain regions that make up various parts of the object you are trying to remember. For example, the memory of a dog includes uniting smell, sound, appearance and name.

Keyword: Learning & Memory
Link ID: 2043 - Posted: 05.10.2002

CHARLESTON (AP) — A pilot fighting off sleep struggles to land his multimillion dollar jet on an aircraft carrier. At the front line, soldiers, themselves weary from too many sleepless nights, mistake one of their own tanks for the enemy as they punch in computer coordinates to bring in supporting fire. Scientists at the Medical University of South Carolina on Thursday received a $2 million government grant to develop technology to reduce the chances for mistakes in such situations where the military fights both the enemy and a lack of sleep. Dr. Mark George and Daryle Bohning of the university's Brain Stimulation Laboratory received a grant from the Defense Advanced Research Projects Agency to research development of a brain stimulation device — likely a helmet — to counter the effects of losing sleep.

Keyword: Sleep
Link ID: 2042 - Posted: 06.24.2010

University of Florida researchers will launch a first-of-its-kind therapy to treat severe traumatic brain injury, a condition for which there is currently no treatment. Many of the million people who sustain severe traumatic brain injuries each year in the United States wind up with severe and lasting disabilities. These injuries occur when a sudden physical assault on the head causes damage that disrupts normal brain function. The major causes of head trauma are motor vehicle accidents, falls and violence. Copyright © 1995-2002 UniSci. All rights reserved.

Keyword: Stroke
Link ID: 2041 - Posted: 06.24.2010

Exclusive from New Scientist Print Edition Researchers are planning to use gene technology to stop the fish producing female offspring, forcing the population to crash. But before that can happen, the scientists will have to show that the strategy, which has already been shown to work in lab fish, will not create more problems than it solves. Ron Thresher of the CSIRO, Australia's national research organisation, and his team hope to introduce multiple copies of a gene called daughterless into carp which would be periodically released into the wild. Copies of the gene are carried by the males, ensuring that it spreads though the population. "If you turn everything into a male, sooner or later the population collapses," says Thresher. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 2040 - Posted: 06.24.2010

Four out of five parents are unaware that children who wet their beds may be suffering from a medical condition. A survey of 1,000 parents suggests the vast majority believe children wet the bed because they are stressed or worried, or in some cases simply out of laziness. However, bedwetting or nocturnal enuresis is a recognised medical condition, which is estimated to affect half a million UK children. In most cases, it can be treated with medication. But the survey - published as part of National Bedwetting Day on Thursday - found nearly half of parents are prepared to ignore the problem and hope their child grows out of it. (C) BBC

Keyword: Sleep
Link ID: 2039 - Posted: 05.09.2002

HOUSTON - A lightweight, imaging cap being designed to assess brain function may go where no MRI has gone before. "On extended space missions, there will be a need to assess brain function as it relates to performance of high-level tasks and in the event of possible illness or injury," said Dr. Jeffrey Sutton, director of the National Space Biomedical Research Institute (NSBRI) and leader of its smart medical systems team. "This portable technology will be beneficial on Earth for assessing, diagnosing and monitoring treatment in brain disorders, such as strokes and seizures." The device utilizes diffuse optical tomography (DOT), a technique using near-infrared light and detectors to record brain activity. The light shines through the skull into the brain and records regional differences in blood flow and oxygen levels. These differences are then analyzed to reveal areas of brain activity. Copyright © 2000-2002 National Space Biomedical Research Institute

Keyword: Brain imaging
Link ID: 2038 - Posted: 06.24.2010

Radio-controlled rodents could go places that St. Bernards can't. But that's not why they're important BY MICHAEL D. LEMONICK In one sense, the news last week that scientists have created a "roborat" represents an ingenious technical breakthrough. Engineers have tried for years--without success--to build robots smart enough to cross even a railroad track. Now, by combining off-the-shelf technology with a creature whose maneuvering skills have been honed by millions of years of evolution, physiologists at the State University of New York Downstate Medical Center in Brooklyn have created remotely piloted rodents that navigate complex terrain at the will of controllers who are more than 500 yards away. Wearing tiny backpacks equipped with radio transmitters and miniature TV cameras, the rats could someday be sent into a collapsed building to find survivors, say the scientists, or into a minefield to sniff out danger or off on a spy mission. But look a little deeper, and the accomplishment is both less and more than meets the eye. It's less in part because the technology involved is so simple. Trainers have known for centuries that you can teach animals to perform all sorts of behaviors with a system of rewards or punishments. Neurophysiologists have known for decades that instead of an external reward like food, you can send electric impulses directly into the brain's pleasure center. Copyright © 2002 Time Inc. All rights reserved.

Keyword: Robotics
Link ID: 2037 - Posted: 06.24.2010

By GERALD NADLER The Associated Press UNITED NATIONS (AP) -- Iodine deficiency, a major cause of mental disabilities and learning difficulties, will be eliminated globally within three years, U.N. officials and salt industry executives predicted Wednesday. Two billion people -- more than 30 percent of the world's population -- still suffer from a deficiency of the chemical element iodine, a leading cause of brain damage in unborn children. The disorder can be alleviated by consuming salt with iodine. By 2005, the deficiency will be completely erased, culminating a 15-year effort by U.N. agencies, civil organizations, and salt producers -- an achievement likened to eliminating smallpox, the United Nations Children's Fund said. Copyright 2002 Associated Press. All rights reserved.

Keyword: Intelligence; Hormones & Behavior
Link ID: 2036 - Posted: 05.09.2002

Kathryn Phillips Most textbooks tell you that primates have a lousy sense of smell, but watch a monkey investigate a piece of food, and the first thing it does is have a good sniff - which doesn't seem like the reaction of an animal with a poor sense of smell. Mattias Laska was intrigued by this apparent conundrum, so he set out to test just how sensitive these animals are to different smells. After testing monkeys with a battery of scents, he's added a selection of alcohols to the primates' repertoire of detected smells, proving that monkeys are better `smellers' than anyone had supposed (p. 1633). Laska has spent the last 15 years training animals to detect specific smells, and most of the time, this isn't easy. Even though dogs have some of the sharpest noses on the planet, very few people have successfully trained dogs in order to test their sensitivity to individual scents. Man is probably the easiest animal to train, so more is known about the human sense of smell. Even then, only 300 monomolecular scents have been tested on us. Having successfully trained a variety of creatures from honey bees up to mammals, Laska was confident that he could successfully train primates to tell him when they could detect smells. He decided to test two primate species' responses to a class of chemicals they encounter in the wild. Ripe fruits emit alcohols at different stages of ripeness, so he tested the animals' sensitivity to eleven alcohol molecules that they might experience in their natural environment. The Journal of Experimental Biology 205, i1101-i1101 (2002) © 2002 The Company of Biologists Limited

Keyword: Chemical Senses (Smell & Taste)
Link ID: 2035 - Posted: 06.24.2010

NewScientist.com news service Secondhand smoke shaves points off kids' IQ, a study of over 4000 American children suggests. Even those exposed to small amounts of cigarette smoke have slightly lower cognitive abilities. "These levels may not be meaningful for an individual child, but they have huge implications for our society because millions of children are exposed to environmental tobacco smoke," says Kimberly Yolton of the Cincinnati Children's Hospital Medical Center in Ohio. Yolton's team looked at levels of a breakdown product of nicotine called cotinine in the blood of 4399 children aged between six and 16. They also examined their scores on a number of intelligence tests, using data from a countrywide survey known as NHANES-III done between 1988 and 1994. To rule out any children who might be smoking themselves, only those with cotinine levels lower than 15 nanograms per millilitre were included. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Intelligence
Link ID: 2034 - Posted: 06.24.2010

By LINDSEY TANNER, AP Medical Writer CHICAGO (AP) - Breast-fed babies may grow up to be smarter adults, according to research that bolsters the evidence linking nursing and intelligence. Most previous studies did not measure breast-feeding's effects on IQ into adulthood, and the few that did so ignored factors such as parents' education and social status, said the researchers, who took such variables into account. In their study of 3,253 Danish men and women, the more babies were breast-fed through 9 months of age, the higher they scored on intelligence tests in their late teens and 20s. Breast-feeding past 9 months had no additional effect on scores. Copyright © 2002 The Associated Press. All rights reserved.

Keyword: Development of the Brain; Intelligence
Link ID: 2031 - Posted: 06.24.2010

CHICAGO --- Researchers have argued for years over whether neurofibrillary tau tangles or beta-amyloid plaques are the primary cause of Alzheimer’s disease. Autopsies show that these hallmarks of Alzheimer’s disease are often found in the same brain regions – preferentially in areas responsible for learning and memory -- but investigators previously have been unable to identify a mechanism linking the two types of lesions. Now, a group of Northwestern University neuroscientists have reported the first evidence showing that tau must be present to enable beta-amyloid to induce the degeneration of brain cells that occurs in Alzheimer’s disease. Adriana Ferreira, M.D., and co-researchers from The Feinberg School of Medicine and the Northwestern University Institute for Neuroscience recently published their findings, which support a key role for tau in the mechanisms leading to beta-amyloid—induced neurodegeneration, in an article in the April 30 issue of the Proceedings of the National Academy of Science. Copyright © 1995-2002 ScienceDaily Magazine

Keyword: Alzheimers
Link ID: 2030 - Posted: 06.24.2010

ITHACA, N.Y. -- Cornell University researchers say the discovery of the two different mutations for X-linked progressive retinal atrophy (XLPRA1 and XLPRA2) in dogs, as reported in the May 1, 2002, issue ofHuman Molecular Genetics (Vol. 11, No. 9), provides a new animal "model" for studying causes and testing treatments for inherited human blindness. Dogs' health and well-being will benefit, too, according to scientists at the Baker Institute for Animal Health in Cornell's College of Veterinary Medicine, because new gene-screening tests will help detect disease-prone animals in breeding programs. The journal report, "DifferentRPGR exon ORF15 Mutations inCanids Provide Insights Into Photoreceptor Cell Degeneration," is the work of Qi Zhang, Gregory M. Acland, Wen X. Wu, Jennifer L. Johnson, Sue Pearce-Kelling and Gustavo D. Aguirre, all at Cornell; Brian Tulloch and Alan F. Wright at the MRC Human Genetics Unit of Western General Hospital in Edinburgh, Scotland; and Raf Vervoort at the University of Leuven in Belgium.

Keyword: Vision; Genes & Behavior
Link ID: 2029 - Posted: 05.08.2002

By KATY J. VOPAL - Freeman Staff WEST ALLIS - When Karen Sebastian was born 37 years ago, her mother, Rose Sebastian, noticed something - a sizable purplish mark on her daughter’s forehead. The mark wasn’t a bruise, it wasn’t a birthmark. It was called a "port wine stain" and was linked to a rare condition called Sturge-Weber syndrome. But now, things are a little different for Rose. Karen died in August 2001 from acute lymphocytic leukemia, and her mother is speaking out about Sturge-Weber to raise awareness about the condition and campaign. The purpose of the campaign is to raise funds for much needed research about the unknown cause and the undiscovered cure of the syndrome. The Sturge-Weber National Day of Awareness is May 15. "Karen was diagnosed right away at birth," Rose said. "She didn’t start having convulsions until 18 months, and it was explained to us that since the stain was up on her forehead, it was linked to calcium deposits around her brain, and that’s what made her have the seizures."

Keyword: Epilepsy
Link ID: 2028 - Posted: 06.24.2010

Placebos Improve Mood, Change Brain Chemistry in Majority of Trials of Antidepressants By Shankar Vedantam Washington Post Staff Writer After thousands of studies, hundreds of millions of prescriptions and tens of billions of dollars in sales, two things are certain about pills that treat depression: Antidepressants like Prozac, Paxil and Zoloft work. And so do sugar pills. A new analysis has found that in the majority of trials conducted by drug companies in recent decades, sugar pills have done as well as -- or better than -- antidepressants. Companies have had to conduct numerous trials to get two that show a positive result, which is the Food and Drug Administration's minimum for approval. What's more, the sugar pills, or placebos, cause profound changes in the same areas of the brain affected by the medicines, according to research published last week. One researcher has ruefully concluded that a higher percentage of depressed patients get better on placebos today than 20 years ago. © 2002 The Washington Post Company

Keyword: Depression
Link ID: 2027 - Posted: 06.24.2010

A candlelit dinner, fresh flowers, an unexpected gift -- all the elements of a fine romance? Or are they part of an evolutionary strategy developed by men to keep track of their women and keep them away from other men during fertile periods? Research to be published in the upcoming issue of Proceedings B, a British Royal Society publication, indicates that women tend to be more interested in sex, in particular with men other than their primary romantic partners, when they are ovulating. (Changes in women's sexual interests and their partners' mate retention tactics across the menstrual cycle: evidence for shifting conflicts of interest by Professor Steven W. Gangestad, Professor Randy Thornhill and Ms Christine E. Garver. PROCEEDINGS OF THE ROYAL SOCIETY: Biological Sciences - Vol. 269, No. 1494.) Copyright © 1995-2002 UniSci. All rights reserved.

Keyword: Sexual Behavior; Evolution
Link ID: 2026 - Posted: 06.24.2010

© 2002 Psychiatric Times. All rights reserved. by Mohamed Fayek, M.D., Steven J. Kingsbury, M.D., Ph.D., and George Simpson, M.D. Psychiatric Times May 2002 Vol. XIX Issue 5 Before deciding that a patient has treatment-resistant schizophrenia, one must first determine that the patient is compliant with medication. Covert noncompliance or partial noncompliance can be missed. A trial with a depot antipsychotic can be helpful in ruling out noncompliance. Similarly, there can be large variations in plasma levels of antipsychotics, even with the same dose. Therapeutic levels of most typical and atypical antipsychotics have not been determined, but blood levels of medications may help determine whether a patient is a rapid metabolizer (or noncompliant). Effective treatment also presupposes an accurate diagnosis. Conditions such as temporal-lobe epilepsy may mimic symptoms of schizophrenia, while comorbid conditions such as endocrinopathies can impact response. Before determining that a patient has treatment-resistant schizophrenia, it is always useful to carefully review the diagnosis.

Keyword: Schizophrenia
Link ID: 2025 - Posted: 06.24.2010