CHAMPAIGN, Ill. — Deciding on hormone-replacement therapy – weighing the far-reaching benefits and risks – can give a woman a headache. Now researchers say estrogen may dictate what problem-solving strategies the brain uses to solve problems. According to a study of rats published in the June issue of Behavioral Neuroscience, activation of different parts of the brain may depend on the presence or absence of estrogen. Rats treated with the hormone learned a place-oriented task faster than rats not getting it, but those not on estrogen were faster completing a response-driven task. These tasks are believed to be controlled by different neural or memory systems. “What we found is that given these analogous tasks that require different cognitive strategies, estrogen biased the rats to use a place, or spatial, strategy,” said Donna L. Korol, a psychology professor at the University of Illinois at Urbana-Champaign. “Those not given estrogen are better using a response, or non-spatial, strategy. This suggests that estrogen isn’t just good for all kinds of memory. Rather, it is very specific in dictating what strategy one takes. Estrogen may enhance some and impair other forms of learning.”

Keyword: Hormones & Behavior; Learning & Memory
Link ID: 2067 - Posted: 06.24.2010

SAN DIEGO -- Like sleuths in an endlessly complex Agatha Christie novel, scientists at The Neurosciences Institute have been trying to solve the mystery of why we need to sleep. Now, following a two-year investigation, they have identified two genetic suspects that suggest one day it may be possible to prevent the consequences of sleep deprivation. The work presented in this week’s Nature, a scientific journal, built upon their previous work showing that sleep in the fruit fly is eerily similar to mammalian sleep, right down to the level of which genes are activated. Now they have shown that, like mammals, flies will die if they don’t sleep. "The significance of the study is that sleep is an important part of life and that without it you die," said lead project scientist Paul Shaw. "It is so important that it has survived throughout evolution even though it is a costly behavior. While animals sleep, they can't take care of their young, forage for food or engage in any number of other vital biological activities."

Keyword: Sleep; Genes & Behavior
Link ID: 2066 - Posted: 06.24.2010

Researchers at the National Institute of Child Health and Human Development (NICHD) and the Howard Hughes Medical Institute have come one step closer to understanding how experimental, memory-enhancing drugs affect the brain on a molecular level. The researchers published their results in the May 16 issue of Nature. The finding provides an important insight into the mechanisms that regulate the sensitivity of brain cells to neurotransmitters, the chemical messengers that the cells use to communicate with one another. “Learning how neurons respond to neurotransmitters is important not only to understanding basic brain functioning, but also may one day lead to new insight into a variety of new therapies,” said Duane Alexander, Director of the NICHD.

Keyword: Learning & Memory
Link ID: 2065 - Posted: 06.24.2010

Trials of a promising new treatment for Alzheimer's will begin within weeks - and it might work for adult-onset diabetes as well. Mark Pepys of the Royal Free and University College Medical School in London and his colleagues have developed a drug designed to rid the body of amyloid, the clumps of misfolded protein that form in the brain of Alzheimer's sufferers and in the pancreas of people with diabetes. The drug has already produced promising results in 19 people with a rare condition called systemic amyloidosis, in which deposits build up in various organs. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 2064 - Posted: 06.24.2010

Key breakthroughs into epilepsy will rely on the consistent support of charities, says a lead researcher specialising in the condition. Internationally renowned Professor John Duncan says: ‘Those with epilepsy can take some comfort from the fact we are narrowing down the likely causes and consequences of this potentially-devastating disease of the brain. ‘But we still have much to learn, and unfortunately this is unlikely to happen without generous donations from charities.’ Paddington Bear ©P & Company 2001

Keyword: Epilepsy
Link ID: 2063 - Posted: 06.24.2010

Copyright © 2002 AP Online By CHRISTOPHER NEWTON, Associated Press WASHINGTON - President Bush's top drug policy adviser says teens are largely ignoring the government's anti-drug ads, and a survey finds no evidence the multimillion-dollar campaign is discouraging drug use. The survey, conducted by the private research firm Westat and the University of Pennsylvania, actually charted an increase in drug use among some teenagers who saw the television ads. But it noted that further analysis was necessary before the ads could be directly tied to the increase. The White House drug policy office, headed by John P. Walters, said the ad campaign must be refocused. Copyright © 2001 Nando Media

Keyword: Drug Abuse
Link ID: 2062 - Posted: 06.24.2010

Scientists said they have found the first direct biological evidence that smoking destroys brain cells and stops others being produced. Anti-smoking groups said this provided an even greater incentive to stop smoking. French researchers led by Pier-Vincenzo Piazza and Djoher Nora Abrous, at the National Institute for Health and Medical Research (INSERM) let three groups of rats give themselves low, medium or high amounts of nicotine. A fourth group was allowed no nicotine at all. (C) BBC

Keyword: Drug Abuse
Link ID: 2061 - Posted: 05.14.2002

A British scientist is still hopeful that cannabis extracts will relieve the symptoms of multiple sclerosis (MS) patients - despite disappointing research results. Testimonies from many MS patients suggest that the drug is helpful in relieving symptoms such as spasticity - a painful rigidity of muscles experienced by many. However, a small Dutch study of only 16 MS patients given cannabis extract in capsule form found no apparent benefits. Despite this, Dr William Nottcutt, a consultant in pain management from the James Paget Hospital in Kings Lynn, said other research projects now coming to fruition were likely to produce more positive results. He said: "This is one study among dozens being conducted into MS. (C) BBC

Keyword: Multiple Sclerosis
Link ID: 2060 - Posted: 05.14.2002

By C. CLAIBORNE RAY [Q] . What is diplopia? How can it be treated? A. Diplopia is the formal medical name for double vision, seeing an object as two objects. (The name is Latin, derived from the Greek words for double and eye.) It is not a single disorder, but can be a symptom of several maladies, with different treatments. It also goes beyond mere blurring, as two competing images are seen, not just a fuzzy image. Perhaps the most common cause of persistent double vision is a muscular problem, with the muscles moving each eyeball being of unequal strength. Thus, the two eyes are not properly aimed for the retina to receive their slightly different views of what they are looking at. As a result, the wrong signals are sent to the brain, and binocular vision fails to merge the images into one. The eyes may appear to be crossed or otherwise misaligned. This problem is sometimes treated with exercise, sometimes with surgery and sometimes with both. Copyright 2002 The New York Times Company

Keyword: Vision
Link ID: 2059 - Posted: 05.14.2002

By MARY DUENWALD Two years ago, after giving up his television series "Spin City," Michael J. Fox created a medical research foundation that is already renowned for its fast-paced disbursements to scientists. Since April of last year, the Michael J. Fox Foundation for Parkinson's Research has given out nearly $17 million to help finance 57 studies. The foundation supports studies covering everything from gene therapy to the effects of caffeine on Parkinson's disease. It has recently dedicated $4.4 million to developing stem cell lines — some derived from embyonic or fetal tissue, some from adult tissue — that could be implanted in the brains of Parkinson's patients to replace the dopamine-producing cells they have lost. It is about to underwrite strategies for reducing dyskinesia, the involuntary movements that are side effects of taking L-dopa, the drug used most often to quell the tremors and rigidity of Parkinson's disease. Copyright 2002 The New York Times Company

Keyword: Parkinsons
Link ID: 2058 - Posted: 06.24.2010

By CAROL KAESUK YOON In the battle for mates, it is the largest males of the animal kingdom that tend to dominate, facing down competitors with their towering height and great girth. But scientists have discovered one battle that conveys the advantage to the teeny-tiny male: the battle with gravity. Scientists at the University of Kentucky have provided one of the best explanations yet for the astonishingly small size of some males. It is a question that has puzzled researchers, including Darwin, for more than a century. The higher up the female spiders spin their webs, the researchers say, the greater the heights the males must scale to reach them, and the smaller these fellows tend to be. Copyright 2002 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 2057 - Posted: 05.14.2002

Cloned Cells Cure Parkinson’s in Rat Model Scientists at Rush-Presbyterian-St. Luke's Medical Center in Chicago have discovered an important shortcut to creating a more efficient, more reliable, and safer source of stem cells with the ability to turn into specific neurons or brain cells. Paul Carvey, PhD, chairman of pharmacology at Rush, used his team's discovery to clone several generations of stem cells that, when grafted into the brains of rats with a Parkinson's like disease, developed into healthy dopamine neurons. This effectively cured the animals' severe Parkinsonian symptoms. The ability to clone large numbers of stem cells that would become neurons also has the potential to revolutionize the treatment of Alzheimer's disease, multiple sclerosis and numerous other diseases and disorders of the brain and nervous system. The findings, and their clinical significance, were presented at the Experimental Biology 2002 meetings in New Orleans last month. This study is the first to identify the signal that instructs stem/progenitor cells to become dopamine neurons, the cells that degenerate in the brain of patients with Parkinson's disease.

Keyword: Stem Cells; Parkinsons
Link ID: 2056 - Posted: 06.24.2010

There are more autistic children in Scotland's schools than has previously been recognised, a charity says. A National Autistic Society (NAS) report has found that one in 121 children have "autism spectrum disorders". This contrasts with estimates of one in 166 made by the Public Health Institute of Scotland last year. The charity is calling on the Scottish Executive and local authorities to act on the findings. However, it is not making any link with the MMR combined measles, mumps and rubella jab, which children are supposed to be administered at primary school. (C) BBC

Keyword: Autism
Link ID: 2055 - Posted: 05.13.2002

WASHINGTON - People's risk for hypertension associated with having a parental history of hypertension may be influenced by observing how their parents handled stress, says researchers who examined relations among numerous behavioral responses and family history of hypertension. This study, reported on in the May issue of Health Psychology, finds that offspring of hypertensive parents react more negatively, both behaviorally and physiologically, to stressful situations. The reason may in part be because certain behaviors, like conflict avoidance and inadequate expression of feelings, were part of their family environments and have been passed from generation to generation in hypertensive families, says lead author Nicole L. Frazer, Ph.D., and colleagues of West Virginia University. Those offspring who have hypertensive parents not only exhibit exaggerated physiological reactivity to stressors but also exhibit learned maladaptive behavioral responses to stressors, said Frazer. © PsycNET 2002 American Psychological Association

Keyword: Stress; Genes & Behavior
Link ID: 2054 - Posted: 06.24.2010

By ANDREW C. REVKIN Scientists working for the Pentagon have trained ordinary honeybees to ignore flowers and home in on minute traces of explosives, a preliminary step toward creating a buzzing, swarming detection system that could be used to find truck bombs, land mines and other hidden explosives. The work is in its early stages, and bees, like bomb-sniffing dogs, have limitations. They do not work at night or in storms or cold weather, and it is hard to imagine deploying a swarm to sniff luggage in an airport. But they also have extraordinary attributes, including extreme sensitivity to scant molecular trails and the ability to cover every nook around the colony as they weave about in search of food. Pentagon officials acknowledge that the idea of bomb-sniffing bees has a public relations problem, a "giggle factor," as one official put it. But that official and scientists working on the project insist the idea shows great potential. Copyright 2002 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 2053 - Posted: 05.13.2002

Fish use ultraviolet vision to choose mates. VIRGINIA GEWIN To truly appreciate guppy beauty takes vision. Ultraviolet vision. Because scientists and conservationists lack this ability, they may not have fully understood what makes some fish sexy to others, until now. Two species of South American fish, the guppy1 and the amarillo2 , use ultraviolet vision to choose mates, two recent studies have found. Females of both species prefer males that they've seen in ultraviolet to those spied when ultraviolet is filtered out. Reflective body stripes and gill covers probably attract the females only when the sun glints off them, suggests the leader of the amarillo study, Constantino Macias Garcia of the Institute of Ecology at the Universidad Nacional Autonoma de Mexico. "We have been missing out on a whole channel of communication in the animal world," says Macias Garcia. * Smith, E. J. et al. Ultraviolet vision and mate choice in the guppy (Poecilia reticulata). Behavioral Ecology, 13, 11 - 19, (2002). * Garcia, C. M. & de Perera, T. B. Ultraviolet-based female preferences in a viviparous fish. Behavioral Ecology and Sociobiology, doi:10.11007/s00265-002-0482-2 (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Keyword: Vision; Sexual Behavior
Link ID: 2052 - Posted: 06.24.2010

By Barbara Feder Ostrov San Jose Mercury News Fifty years ago, physician-supply catalogs carried sugar pills and tonics in many shapes and colors. Known as placebos, these were sham medicines, inert substances that sometimes made sick patients feel better, especially when they came from a kindly, authoritative family doctor. Physicians no longer dispense sugar pills, of course. But the placebo effect remains a powerful force in modern medicine, a mysterious victory of mind over body that seems to flout the cherished objectivity of medical science. New brain-imaging studies show for the first time how and where the placebo effect kindles changes in the brain, renewing interest in the topic. Researchers are searching for ways healers can work with, rather than against, the effect to help patients. Copyright © 2002 The Seattle Times Company

Keyword: Depression; Pain & Touch
Link ID: 2051 - Posted: 06.24.2010

Societal and lifestyle issues—not biology—appear to have the greatest influences on whether men or women live longer By Karen Young Kreeger For as long as demographic records have existed in the United States, women have outlived men. When flappers were big, a woman's life expectancy at birth was about two years more than a man's. Some 50 years later, when disco started taking over the land, the gap had expanded three-fold, to more than seven years. The widening of last century's life expectancy gap between the sexes has been attributed mostly to smoking—men more than women. But in the last few decades, the number of female smokers has increased relative to their male counterparts, effectively narrowing the gap. In 1999, the latest year for which figures are available, a woman's life expectancy at birth was 79.4, and for a man's, 73.9. These fluctuations are not confined to the United States. For example, while not citing specific reasons, the United Kingdom's Government Actuary's Department reports that in 1971, a man was expected to live until nearly 69; a woman, 75. By 2011, the ages are expected to be 77.4 and 81.6, respectively. The smoking scenario has been an important factor in explaining demographics in developed countries, and now it is becoming important in developing countries as well, notes Ingrid Waldron, professor of biology, University of Pennsylvania.1 The Scientist 16[10]:34, May. 13, 2002 © Copyright 2002, The Scientist, Inc. All rights reserved.

Keyword: Sexual Behavior
Link ID: 2050 - Posted: 06.24.2010

Two thirds of teachers in England and Wales think there are more autistic children in primary schools than there were five years ago, according to a report. And the teachers surveyed believe the rate is three times higher in primary than secondary schools. The poll by the National Autistic Society (NAS) also suggests three-quarters of the profession feel there is not enough training offered to teachers in how to deal with autistic needs. The findings, published on the eve of Autism Awareness Week, echo wider public fears that autism cases are on the rise. (C) BBC

Keyword: Autism
Link ID: 2049 - Posted: 05.12.2002

John Pickrell Holding back on the chow may be key to prolonging your pet's life. That's the message from a recently completed study of Labrador retrievers. Since the 1930s, researchers have collected evidence that restricting the diets of rodents and invertebrates can extend their lives and delay the onset of age-related illnesses. In tests, the animals are typically fed a nutritionally complete diet that contains up to 40 percent less carbohydrate, fat, and protein than that given to control animals (SN: 10/5/91, p. 215). A handful of experiments in longer-lived animals, mainly rhesus monkeys, have yielded preliminary evidence that the diet-longevity link extends to larger animals, but most of these studies remain years away from completion (SN: 11/25/00, p. 341: http://www.sciencenews.org/20001125/fob3.asp). In the meantime, the Labrador study provides enlightening results. From Science News, Vol. 161, No. 19, May 11, 2002, p. 291. Copyright ©2002 Science Service. All rights reserved.

Keyword: Obesity
Link ID: 2047 - Posted: 06.24.2010