By Warren King Seattle Times medical reporter Huntington's disease for now has no cure. Treatment focuses on its symptoms — drugs to calm involuntary muscle movements and psychiatric problems. But researchers are homing in on a variety of therapies aimed at the underlying causes of the disease. Much attention has been focused on experiments with transplantation of fetal tissue into the brains of Huntington's patients. Small trials have shown improved cognitive function and muscle coordination in a few patients. The tissue is taken from fetuses aborted in the first trimester and implanted in damaged areas of the brain. It yields healthy brain cells to replace those killed by the disease. And the tissue is not rejected by the body, experiments by University of South Florida and French researchers have shown. Copyright © 2002 The Seattle Times Company

Keyword: Huntingtons; Stem Cells
Link ID: 2271 - Posted: 06.24.2010

Kristin Cobb Women have higher rates of obesity and eating disorders than men do, but scientists don't know why. New findings offer clues to the root of sex differences in eating behaviors. The study showed that men's and women's brains react differently to hunger, as well as to satiation. This is the first research to document sex-specific brain activity related to eating, says study author Angelo Del Parigi of the Phoenix branch of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The report appears in the June American Journal of Clinical Nutrition. Using positron emission tomography (PET), Del Parigi and his colleagues at NIDDK monitored the brains of 22 men and 22 women. A PET scan identifies areas where there are surges in blood flow that reflect activity. The scientists performed the scans after the participants endured a 36-hour fast and again after they drank a liquid meal to quench their hunger. From Science News, Vol. 162, No. 1, July 6, 2002, p. 4. Copyright ©2002 Science Service. All rights reserved.

Keyword: Obesity; Sexual Behavior
Link ID: 2270 - Posted: 06.24.2010

Embryonic mouse stem cells transformed into neurons in a lab dish and then transplanted into a rat model for Parkinson's disease (PD) form functional connections and reduce disease symptoms, a new study shows. The finding suggests that embryonic stem (ES) cells may ultimately be useful for treating PD and other brain diseases. The study is one of the first to show that ES cells can develop into neurons that function in the brain, according to senior author Ronald McKay, Ph.D., of the National Institute of Neurological Disorders and Stroke (NINDS). The report appears in the June 20, 2002, advance online publication of Nature1. A second study in Nature2 , led by Catherine Verfaillie, M.D., at the University of Minnesota in Minneapolis, shows that bone marrow-derived cells called mesenchymal stem cells have many of the characteristics of ES cells. Dr. McKay and his colleagues added a gene called Nurr1 to cultured mouse ES cells and exposed them to a series of growth factors that caused them to develop into neurons. Nurr1 helps neural precursor cells differentiate, or change, into neurons that produce the neurotransmitter dopamine. The loss of dopamine-producing neurons is a central feature of PD. To see if the ES cell-derived neurons would survive and function in animals, the researchers transplanted the neurons into rats that were missing the dopamine-producing cells on one side of their brains. These rats have parkinsonian symptoms on one side of their bodies. A similar group of rats received transplants of ES cells without the Nurr1 gene, and a third group received sham operations.

Keyword: Parkinsons; Stem Cells
Link ID: 2269 - Posted: 06.22.2002

Women suffering from premenstrual syndrome can alleviate their symptoms with a carbohydrate-rich drink, say scientists. Women were given the drink, PMS Escape, twice daily in the five days before their period. The American researchers found that the women, who had mild to moderate symptoms, had less negative mood swings and food cravings after taking the supplement, which increased the brain chemical serotonin. The drink is fruit-flavoured and contains carbohydrates, vitamins, and minerals. But the data in the study, published in the International Journal of Gynaecology and Obstetrics, has been criticised by Professor of gynaecology John Studd. (C) BBC

Keyword: Hormones & Behavior
Link ID: 2268 - Posted: 06.22.2002

Exclusive from New Scientist Print Edition Therapies that aim to rehabilitate stroke patients may be backfiring. Instead of helping people recover lost speech or movement, they could be making the problems worse. That's the conclusion of researchers who found that people who have had strokes were better able to recall words after they silenced parts of the brain that therapies stimulate. Stroke is caused when a clot forms or a blood vessel ruptures in the brain, cutting off the blood supply and killing neurons within minutes. Although the dead cells are not replaced, people can still recover lost functions such as the ability to recall words. © Copyright Reed Business Information Ltd.

Keyword: Stroke
Link ID: 2267 - Posted: 06.24.2010

Bruce Bower In 1992, Karen Wynn's numbers came in big. The numbers in question were tiny in an absolute sense, but they counted for a lot among investigators of child development. The reason: Wynn claimed to have exposed intuitive arithmetic skills of 5-month-old babies. The young psychologist, having received her doctorate in psychology just 2 years earlier, reported that infants show a facility for adding and subtracting small numbers of items, on the order of 1 + 1 = 2 and 2 – 1 = 1. Her results appeared in a major scientific journal, attracted worldwide media coverage (SN: 8/29/92, p. 132), and inspired a wave of research into what she regards as infants' seemingly innate "number sense." Now at Yale University, Wynn is more convinced than ever that babies, along with many nonhuman animals, carry an evolutionary legacy of basic number skills. She's also aware, however, that a spirited debate has emerged about whether the line of research that she's championed really taps into an inborn counting mechanism in the human brain. Some scientists argue that babies use non-numerical visual cues, such as the area and length of the border around visible items, to make quantitative judgments. These handy perceptual features, which vary along with changes in item number, may eventually serve as building blocks when youngsters really learn to count, between ages 2 and 4, in these researchers' view. From Science News, Vol. 161, No. 25, June 22, 2002, p. 392. Copyright ©2002 Science Service. All rights reserved.

Keyword: Development of the Brain; Intelligence
Link ID: 2265 - Posted: 06.24.2010

Kristin Cobb A protein that links gluttony and weight gain may be a novel target for antiobesity drugs. Mice lacking this protein can indulge in fatty food but remain as slim as mice on a lower-fat diet, a new study reports. The finding suggests a new avenue to help morbidly obese people lose weight. When food is scarce, stockpiling energy in fat cells is a survival advantage. But when food is plentiful, as in industrialized countries, genes that promote fat storage lead to obesity (SN: 4/14/01, p. 238: Available to subscribers at http://www.sciencenews.org/20010414/bob17.asp). The molecular mechanisms that translate extra calories into fat deposition are largely unknown. Now, researchers at Kyoto University in Japan have identified a key pathway in the process. Scientists have long known that the hormone called gastric inhibitory polypeptide (GIP) is secreted into the bloodstream by the small intestine in response to ingested foods, particularly fatty ones. GIP binds to cell-surface receptors on distant fat cells, signaling food intake. From Science News, Vol. 161, No. 25, June 22, 2002, p. 387. Copyright ©2002 Science Service. All rights reserved.

Keyword: Obesity
Link ID: 2264 - Posted: 06.24.2010

SAN FRANCISCO, June 21 – Increased levels of the stress hormone cortisol are clearly elevated in child-bearing-aged women who have stopped menstruating – not only in the bloodstream, but also in the cerebrospinal fluid, a senior researcher at the Magee-Womens Research Institute has found. The study is significant because it shows a definitive link between cortisol levels in circulating blood and those in the fluid that surrounds and bathes the brain and spinal cord. "In fact, cortisol levels in the cerebrospinal fluid are even higher than in the circulating bloodstream," said Sarah Berga, M.D., a professor in the departments of obstetrics, gynecology and reproductive sciences and psychiatry at the University of Pittsburgh School of Medicine and a senior investigator at Magee-Womens Research Institute. "This is really important because cortisol is neurotoxic."

Keyword: Hormones & Behavior; Stress
Link ID: 2263 - Posted: 06.24.2010

Seek glimpse into why amputees 'feel' what isn't there By Randy Dotinga HealthScoutNews Reporter HealthScoutNews) -- Scientists are getting a glimpse into how the brain creates a phantom limb, potentially helping them develop new ways to treat amputees who feel pain in body parts that aren't there. In a very unusual case involving a stroke victim's perception of a third arm, researchers at the University of California at San Francisco found activity in a part of the brain that sends signals to the body, not the other way around. That suggests the brain's mental image of the body may play a key role in the development of phantom limbs, says Dave McGonigle, a radiology researcher and co-author of a study that appears in the current issue of Brain. Copyright © 2002 ScoutNews, LLC. All rights reserved.

Keyword: Pain & Touch; Stroke
Link ID: 2262 - Posted: 06.24.2010

SHARON BEGLEY, The Wall Street Journal It wasn't the kind of passage you usually encounter in a strait-laced science journal: "I have had to spend periods of several weeks on a remote island in comparative isolation," Anonymous wrote in Nature. Curiously, he continued, the day before he was due for shore leave his beard grew noticeably: "I have come to the conclusion that the stimulus for (this) growth is related to the resumption of sexual activity." Neither Anonymous nor his fellow scientists were surprised that the aforementioned activity would loose a flood of testosterone, which affects beards the way Miracle-Gro affects tomato plants. No, the weird part is that merely anticipating female companionship did the trick. Just as stress in the med students I wrote about last week altered the expression of genes in their immune systems, so libidinous thoughts seem to affect gene expression, says developmental psychologist David Moore of Pitzer College in Claremont, Calif. Thoughts can cause the release of hormones that can bind to DNA, "turning genes `on' or `off.' " ©2002 Associated Press

Keyword: Genes & Behavior
Link ID: 2261 - Posted: 06.24.2010

By Helen Briggs BBC News Online science reporter Professional musicians have more grey matter in a part of the brain involved in processing music, scientists have found. The discovery could explain why musical virtuosos tend to be born not made. But it is unlikely to resolve the long-running debate about what makes a potential Mozart. Repeated flexing of the brain by practising a musical instrument could account for the extra grey matter in the auditory cortex. The latest twist in the search for a scientific basis of musical ability was made by a team at the University of Heidelberg in Germany. Neurologists played tones of varying frequencies to professional musicians, amateur musicians and non-musicians, and then recorded their brain responses. (C) BBC

Keyword: Hearing
Link ID: 2260 - Posted: 06.22.2002

Almost one in three people with Parkinson's disease suffer from sleep attacks causing them to fall asleep suddenly. A study by doctors in Austria has concluded that the attacks, which have been the subject of controversy, actually do exist. They concluded that the attacks which can happen at any time are caused by the medication taken by patients to alleviate symptoms of the disease. As yet, there is no way of predicting, preventing or treating the attacks. Dr Carl Nikolaus Homann and colleagues at the Karl Franzens University Hospital in Graz, Austria, reviewed studies of 124 patients with Parkinson's disease. They found that 30% had suffered at least one sleep attack. (C) BBC

Keyword: Parkinsons; Sleep
Link ID: 2259 - Posted: 06.21.2002

Exclusive from New Scientist Print Edition The sweet scent of roses or almonds could take some of the pain out of your stay in hospital. But only if you're a woman. Serge Marchand and Pierre Arsenault at the University of Québec in Abitibi-Témiscamingue asked 20 men and 20 women to keep their hand immersed in painfully hot water for as long as they could while smelling various odours. When given pleasant aromas such as almond extract to sniff, the women experienced significantly less pain. Foul smells such as vinegar seemed to slightly intensify their pain. However, the pain felt by the men was not affected by the smells. Both sexes reported feeling happier in the presence of good smells, while bad smells put them in a worse mood. But this effect on the emotions can't be what changed the women's perception of pain. If it was, the men should have responded in the same way. © Copyright Reed Business Information Ltd.

Keyword: Chemical Senses (Smell & Taste); Pain & Touch
Link ID: 2258 - Posted: 06.24.2010

By Eric Haseltine If a stroke robbed you of your visual cerebral cortex (the back of your brain), you'd no longer be able to see. But you wouldn't be blind, strictly speaking, because you'd still be able to unconsciously orient yourself toward visual stimuli and even make your way across a cluttered room without bumping into anything. Such blindsight is made possible by a primitive visual pathway (sometime called the "where" pathway) that controls behavior without conscious vision. You've experienced blindsight if you've ever reflexively reached for a ball suddenly thrown at you. Open your hand as if you were about to pick up one of these silver dollars to experience another example of this mysterious ability. Notice that you automatically opened your fingers wider than if you had reached for one of the dimes. © Copyright 2002 The Walt Disney Company.

Keyword: Vision; Pain & Touch
Link ID: 2257 - Posted: 06.24.2010

By NICHOLAS WADE Scientists working with human embryonic stem cells have converted them into the type of brain cell that is lost in Parkinson's disease, and have shown that the equivalent cells in mice alleviate Parkinson-like symptoms in rodents. "What we are showing here is that we absolutely, definitely have the right cell," said Dr. Ron McKay, a stem cell biologist who works at the National Institutes of Health. The cells produce a neuron-to-neuron signalling chemical called dopamine. The loss of dopamine is believed to cause many of the symptoms of Parkinson's disease. Dr. McKay hopes that the cells he has developed will one day be used to treat the disease, after he has spent two years testing how they work in monkeys. Indeed a surgeon could put them in patients quite quickly "but they wouldn't know what they have done," Dr. McKay said. Copyright 2002 The New York Times Company

Keyword: Parkinsons; Stem Cells
Link ID: 2256 - Posted: 06.21.2002

Using brain cells from rats, scientists at The Johns Hopkins University School of Medicine and the University of Hamburg have manipulated a molecular "stop sign" so that the injured nerve cells regenerate. While their findings are far from application in people, the prospects for eventually being able to repair spinal cord injury are brighter, they say. "Four thousand years ago, physicians wrote that spinal cord injury was untreatable, and unfortunately it's much the same today," says Ronald L. Schnaar, Ph.D., professor of pharmacology and of neuroscience at Hopkins. "But the basic-science framework for improving this situation is quickly emerging."

Keyword: Regeneration; Development of the Brain
Link ID: 2255 - Posted: 06.21.2002

From The Economist print edition Researchers can now watch the brain as memories are stored within it BEFORE a big exam, a sound night's sleep will do you more good than poring over your textbooks. That, at least, is the folk wisdom. And science, in the form of behavioural psychology, supports that wisdom. But such behavioural studies cannot distinguish between two competing theories of why sleep is good for the memory. One says that sleep is when permanent memories form. The other says that they are actually formed during the day, but then “edited” at night, to flush away what is redundant. To tell the difference, it is necessary to peer into the brain of a sleeping person, and that is hard. But after a decade of painstaking work, a team led by Pierre Maquet of the Cyclotron Research Centre at Liège University in Belgium has managed to do it. Dr Maquet and his colleagues have persuaded enough people to fall asleep inside a noisy, cramped brain-scanning machine to collect the evidence needed to show what is happening. Steven Laureys, one of Dr Maquet's collaborators, revealed their results to a meeting of the Organisation for Human Brain Mapping in Sendai, Japan, earlier this month. Copyright © 2002 The Economist Newspaper and The Economist Group. All rights reserved.

Keyword: Learning & Memory; Sleep
Link ID: 2254 - Posted: 06.24.2010

UPTON, NY — The idea that obese people eat too much because they find food more palatable than lean people do has gained support from a new brain-imaging study at the U.S. Department of Energy’s Brookhaven National Laboratory. The study reveals that the parts of the brain responsible for sensation in the mouth, lips, and tongue are more active in obese people than in normal-weight control subjects. “This enhanced activity in brain regions involved with sensory processing of food could make obese people more sensitive to the rewarding properties of food, and could be one of the reasons they overeat,” said Brookhaven physician Gene-Jack Wang, lead author of the study. Wang acknowledges that obesity is a complex disease with many contributing factors, including genetics, abnormal eating behavior, lack of exercise, and cultural influences, as well as cerebral mechanisms, which are not yet fully understood. In a recent study, he and his team found that obese people have fewer brain receptors for dopamine, a neurotransmitter that helps produce feelings of satisfaction and pleasure, implying that obese people may eat to stimulate their underserved reward circuits, just as addicts do by taking drugs.

Keyword: Obesity; Brain imaging
Link ID: 2253 - Posted: 06.24.2010

Denied sugar, bingeing rats suffered withdrawal It's a common refrain: "I'm addicted to sugar." Now a study by Princeton University psychologists suggests that such urges really may be a form of addiction, sharing some of the physiological characteristics of drug dependence. Although the term "sugar addiction" often appears in magazines and on television, scientists had not demonstrated that such a thing as sugar dependency really exists, said neuroscientist Bart Hoebel, who led the study. Hoebel and colleagues studied rats that were induced to binge on sugar and found that they exhibited telltale signs of withdrawal, including "the shakes" and changes in brain chemistry, when the effects of the sweets were blocked. These signs are similar to those produced by drug withdrawal. Sugar, said Hoebel, triggers production of the brain's natural opioids. "We think that is a key to the addiction process," he said. "The brain is getting addicted to its own opioids as it would to morphine or heroin. Drugs give a bigger effect, but it is essentially the same process."

Keyword: Obesity; Drug Abuse
Link ID: 2252 - Posted: 06.21.2002

Copyright © 2002 United Press International BALTIMORE, - Scientists announced Wednesday they have figured out a new way to get nerve cells to regenerate in the laboratory and have come one step closer to being able to repair spinal cord injuries - although that prospect remains years away. "For the first time in history there is some optimism that we may be able to get functional recovery of spinal cord injuries," Ronald L. Schnaar, co-author of the study and professor of pharmacology and of neuroscience at Johns Hopkins University, told United Press International. "Whether it's this decade or next decade, I think we'll begin to see this knowledge turned into therapies." Schnaar and colleagues at the University of Hamburg, Germany, discovered how to modulate a molecular signal that inhibits the regeneration of nerve cells after they are damaged. Copyright © 2001 Nando Media

Keyword: Regeneration; Brain Injury/Concussion
Link ID: 2251 - Posted: 06.24.2010