Old epidemic sheds new light on vCJD XAVIER BOSCH New evidence from an old epidemic could help those trying to estimate how many people may be incubating variant Creutzfeldt–Jakob disease (vCJD) - the human form of mad cow disease. So say scientists in the United States who have studied DNA extracted from victims of the first documented prion disease, kuru1. Like vCJD, kuru is a neurodegenerative disease caused by infection with a rogue 'prion' protein. The disease spread among the Fore people of Papua New Guinea in the 1940s and 1950s as a result of their cannibalistic funerary rituals. 1.Lee, H.-S. et al. Increased susceptibility to kuru of carriers of the PRNP 129 methionine/methionine genotype. Journal of Infectious Diseases 183, 192–196 (2001). © Macmillan Magazines Ltd 2001 - NATURE NEWS SERVICE Nature © Macmillan Publishers Ltd 2001 Reg. No. 785998 England.

Keyword: Prions
Link ID: 189 - Posted: 06.24.2010

It Takes Training and Genes to Make a Mean Dog Mean By MARK DERR The fatal mauling of a San Francisco woman by her neighbors' dog on Jan. 26 revives the question of whether some dog breeds are more inherently violent than others and should be banned as pets. The woman, Diane Whipple, a 33-year-old lacrosse coach, was killed at the door of her apartment by a 120-pound cross between a Canary Island dog and mastiff. The neighbors' second dog, the same kind of mixed breed, weighed 113 pounds and may have been involved in the attack. Law-enforcement officials say the dogs were being raised as part of a scheme to produce fighting and "guard" dogs for Mexican methamphetamine labs. Copyright 2001 The New York Times Company

Keyword: Genes & Behavior
Link ID: 188 - Posted: 10.20.2001

Brahms Needed More Than a Lullaby for a Night's Rest Washington Post By all accounts, he was a short, bad-tempered, bearded fat guy who frequently drank too much, and who, later in life, acquired the habit of falling asleep in Vienna pastry shops at tea time, much to the amazed glee of passing tourists. This was Johannes Brahms? Too true, says researcher Mitchell Margolis. All of these well-documented Brahmsian traits, Margolis said, suggest that the composer of history's most famous lullaby suffered from obstructive sleep apnea - a sleeping disorder. ©2001 San Francisco Chronicle Page A8

Keyword: Sleep
Link ID: 187 - Posted: 11.06.2001

PERSONALITY INFLUENCES THE BRAIN'S RESPONSES TO EMOTIONAL SITUATIONS MORE THAN THOUGHT, ACCORDING TO NEW RESEARCH Extraverts Show More Brain Reactivity to Positive Images Than Introverts Washington - How our brains respond to different environmental stimulus is in large measure a result of what type of personality we have, according to a new study that examines brain activity by magnetic resonance imaging (MRI). This study published by the American Psychological Association in this month's journal of Behavioral Neuroscience suggests that depending whether a person is extraverted or neurotic, his or her brain will amplify different experiences over others. In their study, psychologists Turhan Canli, Ph.D., and colleagues of Stanford University used functional magnetic resonance imaging (fMRI) to measure the relation between brain responses to emotional stimuli - pictures. While in a fMRI scanner, 14 healthy 19-42 year old women's brain reactions to pictures containing negative images (crying or angry people, spiders, guns or a cemetery) or positive images (happy couple, puppies, foods like ice cream or brownies or sunsets) that provoked strong emotional reactions were determined.

Keyword: Emotions
Link ID: 186 - Posted: 10.20.2001

Sometimes, placebos work-but how? By Damaris Christensen Simply participating in a medical-research trial sometimes improves a person's health. That's why investigators use placebos-inert pills or other dummy treatments-and make both study participants and staff unaware of whether a person is receiving an active treatment or not. Anywhere from 10 to 100 percent of the people taking placebos in trials see their symptoms wane. In such a test, a drug is considered to be beneficial only if it can beat the placebo. Many studies suggest that problems like pain and depression respond particularly well to placebos. Blood pressure, cholesterol concentration in the blood, and heart rate are also affected by placebos, as are warts. On average, about a third of people taking placebos in studies report a benefit. From Science News, Vol. 159, No. 5, Feb. 3, 2001, p. 74. Copyright © 2001 Science Service. All rights reserved.

Keyword: Pain & Touch
Link ID: 185 - Posted: 10.20.2001

No Longer Alone: The Scientist Who Dared to Say Animals Think By EMILY EAKIN Donald Griffin was at the Central Park Zoo last month watching the polar bears nuzzle a synthetic log smeared with Skippy. "They really like that peanut butter," Dr. Griffin observed as Gus, 800 pounds, tried to fit his nose into an enticingly sticky knothole. To the untutored eye it looked like just another feeding time at the zoo, but at Central Park the exercise with the log and snack goes by the grander name of "animal enrichment" and is intended to stimulate the bears' minds as well as their appetites. It's a concept for which the bears have Dr. Griffin, 85, in large part to thank. Copyright 2001 The New York Times Company

Keyword: Animal Communication
Link ID: 184 - Posted: 10.20.2001

Evolution of Sexual Dimorphism Researchers determine how the male fruit fly got his rear By Ricki Lewis Sexual dimorphism makes life interesting for many species. In the case of the fruit fly Drosophila melanogaster, the rear end of a male is so much darker than that of a female that a seasoned fly pusher can distinguish he from she even without the aid of a microscope. A telling investigation by Artyom Kopp and Sean Carroll at the Howard Hughes Medical Institute and Laboratory of Molecular Biology at the University of Wisconsin-Madison and Ian Duncan at the Department of Biology at Washington University in St. Louis suggests how sexual selection could have maintained the distinctive abdominal differences in two steps.1 The Scientist 15[3]:18, Feb. 5, 2001 © Copyright 2001, The Scientist, Inc. All rights reserved.

Keyword: Epilepsy
Link ID: 183 - Posted: 10.20.2001

Technology shows alcohol abuse changes brain's molecular programming and circuitry By A.J.S. Rayl Researchers have suspected for years that chronic alcohol abuse and alcoholism change the programming of the human brain at the molecular level, particularly in the regions involving judgment and decision-making. In fact, during the past several decades, cell and animal studies have consistently indicated that changes in gene expression in the brain appear to be responsible for the tolerance, dependence, and neurotoxicity produced by chronic alcohol abuse.1 Until recently, however, technological limitations prevented any kind of large-scale approach to confirm this hypothesis. "As research has evolved over the past five years or so, a consensus emerged that neuroadaptation to drugs, which is part of drug addiction--aspects such as development of tolerance to the drug action, or development of physical dependence--likely are caused by changes in gene expression; but until the gene arrays came along, it was a real needle in a haystack to try and find which gene might be important in addiction," confirms Adron Harris, director of the Waggoner Center for Alcohol and Addiction Research at the University of Texas, Austin. The Scientist 15[3]:16, Feb. 5, 2001 © Copyright 2001, The Scientist, Inc. All rights reserved.

Keyword: Evolution; Apoptosis
Link ID: 182 - Posted: 10.20.2001

Dopamine receptors implicated in obesity A deficiency of dopamine in the brain may explain why some individuals engage in pathological overeating, resulting in severe obesity, according to a stufy published in this week's Lancet. Dopmamie is a neurotransmitter that acts in the brain and helps regulate feelings of pleasure and modulates the rewarding properties of food. Based on their findgs, the researchers believe that individuals deficient in dopmaine receptors may need to eat more than people with higher dopamine levels to induce feelings of satisfaction and gratification.

Keyword: Obesity
Link ID: 181 - Posted: 10.20.2001

Ulysses Torassa, Chronicle Medical Writer
Friday, February 2, 2001 - Like marijuana before it, MDMA -- ecstasy to its users -- is being touted as a potential therapy, and a handful of psychiatrists are agitating for permission and money to study the illegal drug in controlled settings. "This substance is a potent, immediate-acting antidepressant, and there is no such thing right now in psychiatry," said Dr. Julie Holland, a psychiatrist at Bellevue Hospital in New York and editor of the forthcoming book, "Ecstasy: The Complete Guide." ©2001 San Francisco Chronicle

Keyword: Depression
Link ID: 180 - Posted: 10.20.2001

Find that tune JOHN WHITFIELD You are a famous conductor rehearsing with a symphony orchestra. One of the second violins scrapes a bum note. Fortunately, as researchers in Germany now show, years of experience have made your brain unusually adept at pinpointing where a particular sound is coming from, allowing your maestro's tirade to hit home with terrifying accuracy. Thomas Münte of the University of Magdeburg, Germany, and colleagues compared conductors' sonic accuracy with that of classical pianists and non-musicians, all of whom had on average more than 15 years of professional experience. Münte's team found that conductors can focus their hearing more sharply even than other professional musicians1. Orchestral conductor Leon Gregorian teaches conducting at Michigan State University, East Lansing. Listening to individual musicians, he says, "is a skill that you begin to develop". .... 1.Münte, T. F., Kohlmetz, C., Nager, W. & Altenmüller, E. Superior auditory spatial tuning in conductors. Nature 409, 580 (2001). © Macmillan Magazines Ltd 2001 - NATURE NEWS SERVICE Nature © Macmillan Publishers Ltd 2001 Reg. No. 785998 England.

Keyword: Hearing
Link ID: 179 - Posted: 10.20.2001

No Pain, No Brains? Intelligence comes at a painful price--at least it does for one strain of genetically engineered mice. In the February issue of Nature Neuroscience, researchers show that transgenic mice previously shown to score high on mouse intelligence tests are more sensitive to chronic pain. The finding bolsters a link between the physiological mechanisms of pain and memory and could point the way to better drugs for chronic pain. A year and a half ago, the engineered mice caused a media stir, when their creators at Princeton University reported in Nature that they outperformed their normal counterparts on a variety of learning and memory tests (ScienceNOW, 1 September 1999). The researchers had meddled with the animals' so-called NMDA receptors, which play a variety of roles in the central nervous system; the "smart" mice make an abundance of a particular type of NMDA receptor which contains the so-called NR2B subunit. --GREG MILLER Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 177 - Posted: 10.20.2001

JAMES GLANZ
From sublime poetry to serious malady, the brain is the focus of some of the most complex phenomena in nature. But sometimes, it is just another electrical circuit that can be controlled with the flip of a switch. That, at least, is one possible conclusion to be drawn from a paper in the Jan. 15 issue of The Journal of Neuroscience. The authors of the paper, titled "Adaptive Electric Field Control of Epileptic Seizures," used slices of rat brain as just another element of an electrical feedback circuit. The circuit sensed when the specially treated brain slices were firing spasmodically in a way that mimicked an epileptic seizure, and then shut the seizure off by applying weak electric fields to the slices. Copyright 2001 The New York Times Company

Keyword: Epilepsy
Link ID: 176 - Posted: 10.20.2001

Mad Cows and Panicked People U.S.: Anxiety spreads despite precautions Keay Davidson, Chronicle Science Writer Monday, January 29, 2001 Can it happen here? As panic has swept Europe over mad cow disease - a public health disaster that has killed 80 people there - Americans have assumed that their beloved burgers and steaks are safe. But now anxiety seems to be spreading in the United States. Among the latest signs: Last week, federal health officials announced that a Texas cattle herd was being checked for possible contamination by the disease, after a feed mill admitted recycling cattle parts into the animals' feed. ©2001 San Francisco Chronicle Page A1

Keyword: Prions
Link ID: 175 - Posted: 10.20.2001

After decades of neglect by researchers more interested in know-it-all neurons, the brain cells classified as "glia" are getting some respect. They've been written off as support scaffolding for neurons or as caterers that provide nutrition. But now researchers have found that glia play an important role in setting up neural networks: They tell neurons to start talking to one another. Neurons send and receive messages through connections called synapses, points of near-contact where neurons swap chemical signals. The first indication that glia boost synaptic communication came in 1997, when a team led by neurobiologist Ben Barres of Stanford University reported that neurons grown near glial cells called astrocytes were 10 times as responsive as neurons grown alone. They just didn't know why. --LAURA HELMUTH Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Glia
Link ID: 174 - Posted: 10.20.2001

Marijuana is reputed to set the mood for love, particularly in females. Now scientists have new insights into how the drug exerts its effects--at least in rats. A study published in the 23 January Proceedings of the National Academy of Sciences shows that the drug's active compound influences acts through two chemical messengers known to have a strong influence on reproductive behavior. In rats as in people, sexual behavior requires certain hormones. If the ovaries are removed from a female rat, for example, she will no longer raise her rump when she's ready to mate. This behavior can be restored with injections of the sex hormones estrogen and progesterone--and also with shots of marijuana's active ingredient, 9-tetrahydrocannabinol (THC). Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Hormones & Behavior
Link ID: 173 - Posted: 10.20.2001

Big Babies May Grow Up Smarter Study suggests heftiness could mean a higher intellect, at least until middle age Carl T. Hall, Chronicle Science Writer Friday, January 26, 2001 Babies born a little bigger than average seem to grow up into smarter kids and young adults, scientists said yesterday. But they also found that size at birth doesn't seem to matter much by the time you reach middle age. In a large study of youngsters born in England, Scotland and Wales just after World War II, researchers found a significant link between birth weight and performance on standard cognitive tests. ©2001 San Francisco Chronicle Page A6

Keyword: Development of the Brain
Link ID: 172 - Posted: 10.20.2001

January 26, 2001- Researchers have identified a protein in the nervous system of fruit flies that is a cousin of the molecule that cocaine targets in the human brain. Their discovery offers the possibility that researchers can genetically manipulate the protein in fruit flies to gain better understanding of how cocaine alters behavior and produces addiction. ©2001 Howard Hughes Medical Institute

Keyword: Drug Abuse
Link ID: 171 - Posted: 10.20.2001

When Rats Dream, It Seems, It's After a Day at the Mazes By ERICA GOODE Elephants dream of munching sweet grass under a starry savannah sky. Dogs, paws aquiver, tails thumping faintly in slumber, chase squirrels in the park. And cats, of course, dream of mice. Or so humans, prone to anthropomorphic conjecture about the four- legged world, have long suspected. Yet what animals dream about - or indeed, whether they dream at all - has remained resistant to scientific scrutiny, if only because animals cannot describe their closed-eye experiences in words. Copyright 2001 The New York Times Company

Keyword: Sleep
Link ID: 170 - Posted: 11.06.2001

The Laboratory of Neuro Imaging was originally established to study cerebral metabolism with the goal of understanding the relationship between brain structure and function using image data. Work progressed into three-dimensional reconstruction and visualization. This enabled the study of functional anatomy in the same geometric configuration as that found in the living animal. As these reconstructions became more sophisticated, their application to computational atlases became possible. Human brain structure and function are so complex that powerful computational tools are required to analyze brain data. Given the fact that there is neither a single representative brain nor a simple method to construct an 'average' anatomy or represent the complex variations around it, the construction of brain atlases became the focus of intense research. Brain atlases are based on detailed representations of anatomy in a standardized 3D coordinate system. The Laboratory addressed the prob! lem of comparing data across individuals as well as across modalities and increased work in humans began. Work focused on statistical manipulation of the geometry that made up the anatomic and functional data sets as well as sophisticated visualizations permitting the communication of the results.

Keyword: Miscellaneous
Link ID: 168 - Posted: 10.20.2001