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BY BRIAN BRUEGGEMANN It sounds like something from a soap opera. Jim Schauster drives 4,000 miles, feeds himself during the nearly three-week trip, checks into a hotel for at least one night, drives back home, then doesn't remember any of it. Experts on amnesia say it sounds as if Schauster may have experienced a phenomenon known as a fugue state -- an amnesic event where a person functions in a sort of twilight zone. "They travel long distances in these states, and they don't realize where they've been until they come around and they see that they've got a ticket or a hotel bill or something on them," said Dr. Michael Kopelman of London, one of the world's top experts on memory loss. Kopelman said he sees two or three patients a year who arrive in London with no idea who they are or why they're there. He said they usually snap out of it due to "some chance cue in the environment," such as one patient who saw a book title that reminded him of a friend. Schuaster, 53, of Highland had been missing since June 18, when he showed up Tuesday morning at St. Joseph's Hospital in Highland. He said he was driving and realized he was in nearby St. Jacob, but he didn't know why, so he went straight to the hospital. Lt. John Lakin of the Madison County sheriff's department said police have no reason to doubt him.

Keyword: Learning & Memory
Link ID: 5792 - Posted: 07.14.2004

By Rob Stein, Washington Post Staff Writer For decades, scientists thought fat cells were passive blobs that did nothing more than store energy, bloat flabby hips and bellies, and perhaps wear down the body by forcing it to cart around a lot of extra weight. But as the nation's obesity crisis has intensified scientific interest in fat, researchers have fundamentally altered that view: Fat cells, they now realize, are extraordinarily dynamic, complex and influential entities that affect a staggering array of crucial bodily functions. The new insights into fat's commanding, self-sustaining powers, scientists say, have profound implications for understanding how flab forms, why it hangs on so stubbornly, how it causes disease, and therefore possibly how to help people shed pounds and avoid the devastating health problems wrought by fat cells. "They were always thought to be poor, dumb sacks of lard," said Roger Unger, an obesity researcher at the University of Texas Southwestern Medical Center. "It turns out that they end up being very talented, very versatile, very important players." © 2004 The Washington Post Company

Keyword: Obesity
Link ID: 5791 - Posted: 06.24.2010

US scientists believe nerve cells critical for gasping offer important clues to the cause of cot death. Dr Jan-Marino Ramirez and colleagues at the University of Chicago have found two brain cell pathways that drive breathing baby mice. Normally, one pathway will compensate if the other is blocked, causing the baby to gasp to take in air. Cot deaths may occur if both pathways become blocked for some reason, say the authors in the journal Neuron. Normally, if a baby becomes short of oxygen for any reason they will gasp. Dr Ramirez's team had previously shown a specific group of pacemaker neurons in the brain controlled gasping in baby mice. They had thought all of the neurons communicated in the same way, via sodium channels. However, when scientists used a drug that blocks sodium they found only some of the neurons stopped communicating. According to Dr Raminez this meant there must be two pathways that instructions to make the baby gasp. (C)BBC

Keyword: Sleep
Link ID: 5790 - Posted: 07.14.2004

By ANDREW POLLACK Amgen's anemia drug, the best-selling product developed so far by the biotechnology industry, might have broad new uses, recent studies have found. Laboratory and animal studies have shown that in addition to bolstering the body's red blood cells, the drug, EPO, is present in the central nervous system and acts to protect cells and tissues from damage and death. That could make it useful as a treatment for strokes, spinal cord injuries, multiple sclerosis and many other ailments. Testing in humans is in very early stages. A small study by academic scientists in Germany found that EPO, when given within eight hours of a stroke, helped protect the brain from damage and improve patient recovery. A larger trial is now under way there. Another early-stage trial in Germany is testing EPO as a treatment for schizophrenia, and in the United States, academic scientists are planning trials for AIDS-related dementia and for a nerve disease similar to multiple sclerosis. EPO, short for erythropoietin, is sold by Amgen as Epogen and, in a newer form, as Aranesp. Johnson & Johnson, under license from Amgen, sells it under the names Procrit and Eprex. The versions had combined sales of $8 billion last year. Copyright 2004 The New York Times Company

Keyword: Stroke; Regeneration
Link ID: 5789 - Posted: 07.10.2004

Carrie Lock Next time you can't make out a distant highway sign, blame your parents. Scientists in the United Kingdom have found that myopia, or nearsightedness, is predominantly hereditary, and they're beginning to unravel the genetic mechanism that causes the vision problem. Roughly a third of people in the United States suffer from myopia—they clearly see close objects, such as words in a book, but things in the distance appear blurry. The anatomic root of the problem is an elongation of the eye as it grows, causing incoming light to focus in front of the retina, instead of squarely on it, explains Christopher J. Hammond of St. Thomas' Hospital in London. Using a noninvasive technique, Hammond measured the sizes of the eyeballs of 280 sets of fraternal adult twins and 226 sets of identical twins. By mathematically modeling the differences in the eye sizes, Hammond found that genes accounted for 89 percent of nearsightedness, farsightedness, and other refractive vision problems, he reports in the August American Journal of Human Genetics. Copyright ©2004 Science Service.

Keyword: Vision
Link ID: 5788 - Posted: 06.24.2010

Scientists at the National Institute of Dental and Craniofacial Research (NIDCR), one of the National Institutes of Health, and their colleagues have isolated human postnatal stem cells for the first time directly from the periodontal ligament, the fibrous, net-like tendon that holds our teeth in their sockets. The scientists also say these cells have "tremendous potential" to regenerate the periodontal ligament, a common target of advanced gum (periodontal) disease. This enthusiasm is based on follow up experiments, in which the researchers implanted the human adult stem cells into rodents, and most of the cells differentiated into a mixture of periodontal ligament — including the specific fiber bundles that attach tooth to bone — and the mineralized tissue called cementum that covers the roots of our teeth. "The stem cells produced beautifully dense, regenerated tissue in the animals," said Dr. Songtao Shi, a senior author on the paper and an NIDCR scientist. "That was when we knew they had great potential one day as a treatment for periodontal disease, and we're continuing to follow up on this promise with additional animal work." The results are published in the current issue of The Lancet. Shi said scientists have suspected since the 1970s that the periodontal ligament might contain its own unique stem cells. But, for a variety of technical reasons, the search had come up empty, leaving some to wonder whether stem cells could be extracted from such a tiny bit of tissue known to contain a confusing mixture of cell types and subsets.

Keyword: Stem Cells; Regeneration
Link ID: 5787 - Posted: 06.24.2010

It looks like a fat carrot, but it is actually a banana. And it is so rich in precursors to vitamin A that researchers hope it could prevent children from going blind in the Pacific islands of Micronesia. Dubbed the "karat" because of its bright orange flesh, the unusual banana has been used for centuries in Micronesia to wean infants onto solid food. But today it is rarely eaten there, as imported foods have grown in popularity. The "karat" had been used for centuries in Micronesia to wean infants (Image: Lois Englberger, University of Queensland, Aus) That now looks set to change. A screening programme sponsored by the agriculture ministry of Pohnpei, a Micronesian island, has established that the karat is unusually rich in beta-carotene, which the body converts into vitamin A. The hope is that the fruit could now be routinely given to children deficient in this vitamin, to help them avoid developing certain kinds of blindness. © Copyright Reed Business Information Ltd

Keyword: Vision
Link ID: 5786 - Posted: 06.24.2010

Helen Pilcher Machines that can be controlled by the mind have moved a step closer to reality. Researchers have trained monkeys to 'think' a cursor around a computer screen to reveal their preferences and goals. It is hoped the technology will lead to devices that can display the thoughts of paralysed people who are unable to communicate through speech or sign. It could also aid the development of artificial limbs and robots that are operated by the brain alone. In the past couple of years, researchers have already developed chips that recognise brain signals for movement and convert them into action. Monkeys fitted with the devices have been trained to move cursors around monitors. Such devices translate signals from the brain's motor cortex, the region that directs physical movement. But now Richard Andersen from the California Institute of Technology, Pasadena, and colleagues have decoded signals from a different region, the parietal cortex, which helps us plan our actions. Their study is published in Science1. ©2004 Nature Publishing Group

Keyword: Vision; Robotics
Link ID: 5785 - Posted: 06.24.2010

By HENRY FOUNTAIN Everybody's got rhythm - circadian rhythm, that is. From the most multicellular of creatures (humans included) to single-cell bacteria, many organisms display activities and behavior that oscillate precisely with daily cycles of light and dark. Almost nobody has perfect rhythm. In a multicellular organism, the circadian clocks of individual cells may be slightly out of whack. Communication among cells, however, allows them to synchronize so that the organism's precise rhythm is maintained. But what about bacteria? Colonies have been shown to have precise circadian cycles by which genes express certain compounds. But is that because communication adjusts the variations among individual organisms? Or are the individual clocks more accurate? Dr. Irina Mihalcescu of Joseph Fourier University in France has answered that question, at least for a certain kind of bacteria - cyanobacteria, or blue-green algae. These organisms, she and colleagues report in the journal Nature, are like Swiss watches. Their circadian rhythms are extremely precise. Copyright 2004 The New York Times Company

Keyword: Biological Rhythms
Link ID: 5784 - Posted: 07.09.2004

Cockroaches, perhaps the most unpopular of all unwelcome insect houseguests, have probably been around for 280 million years, and they'll probably still be around after we're gone. These speedy, hearty critters are almost indestructible—they can even live for a whole week without their heads. Roaches are a source of disgust for most of us. But Mark Cutkosky, mechanical engineer and co-director of the Center for Design Research at Stanford University is proving that one man's frustration is another man's inspiration. Cutkosky and his research group, along with Robert Full, biomechanics professor and director of the Poly-PEDAL lab, and his team at the University of California at Berkeley, designed the Sprawl family of legged robots based on the way roaches move (AKA "bio-inspired"). "Roaches, if you want to do small things that run fast, are a pretty good exemplar," says Cutkosky. "They're very robust, they move remarkably fast—20, 25 even up to 50 body lengths per second for the American cockroach. That's much faster per scale-to-size than you and I can run. They're very stable and they run with a very simple control system." © ScienCentral, 2000- 2004.

Keyword: Robotics
Link ID: 5783 - Posted: 06.24.2010

Henry Gee How could sophisticated mechanisms such as the flagellar motor or the adaptive immune system have evolved without some guiding hand? Henry Gee finds his answer to the argument of Intelligent Design in the lamprey. We are accustomed to thinking of ourselves as peaks of perfection, and the arrangements of more "primitive" creatures as similar to our own, only cruder. It's a nice idea. Until along comes the sea lamprey to challenge our preconceptions. Researchers have found that the lamprey (Petromyzon marinus) has a has a sophisticated system of adaptive immunity, that is entirely different to our own. Many organisms have a kind of natural immunity, but the adaptive immunity of mammals was supposed to be something special. By dint of a kind of controlled chaos, specialized parts of our genomes rearrange themselves to produce antibodies, custom-built proteins that are then selected to target any kind of foreign molecule the world can throw at us. One of the great mysteries of immunology is how and when this remarkable system originated. For many years, immunologists looked for its beginnings in lampreys, sucker-mouthed creatures that represent the earliest flourish of vertebrate evolution more than 500 million years ago. Lacking jaws and paired fins, lampreys are almost as primitive as a vertebrate can get. They seem to have adaptive immunity, but scientists haven't found even a glimmer of any antibodies. ©2004 Nature Publishing Group

Keyword: Evolution
Link ID: 5782 - Posted: 06.24.2010

By ROWAN HOOPER Everyone knows someone who is a compulsive womanizer; a man who simply can't remain faithful to one woman. Likewise, everyone knows someone who is a doting, faithful husband; for such a man the idea of sex with women other than his partner is unthinkable. Ever wondered why men are so different? Scientists working on one of the few other mammal species to form a pair bond have found the beginnings of an answer. Miranda Lim and colleagues at the Center for Behavioral Neuroscience, Emory University, Atlanta, Ga., have focused their research on prairie voles, one of the few mammal species that are monogamous and form lifelong pair bonds. They chose prairie voles as their study species because there is a closely related species that, although very similar genetically, exhibits very different social behavior. While the male prairie vole is monogamous, the male meadow vole is polygamous. And by changing just one gene in the meadow vole, the biologists reversed its polygamy: They turned the "love rat" into a cuddly, loving little rodent. The Japan Times 2004 (C) All rights reserved

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 5781 - Posted: 07.09.2004

BERKELEY – Organisms ranging from bacteria to humans navigate environments that can contain dangerously too little or too much oxygen. Yet, scientists know little about how animals sense oxygen levels around them. Researchers from the Berkeley and San Francisco campuses of the University of California have now discovered how the nematode C. elegans senses oxygen levels in order to steer clear of surrounding areas that are too low or too high in oxygen. In the process, the researchers also discovered that the worm doesn't like as much fresh air as people thought. While nematodes grown in laboratory Petri dishes are kept at the same oxygen concentration humans breathe in ambient air - 21 percent - nematodes appear to prefer only 6 percent oxygen. "It was totally unexpected that they would actually prefer 6 percent. We don't know why, though it probably gives them some survival advantage," said Michael A. Marletta, professor of chemistry and of molecular and cell biology at UC Berkeley, and a faculty scientist at Lawrence Berkeley National Laboratory (LBNL). "And the bordering and clumping that worm experts refer to as social behavior is really the worms, in an artificial setting like a Petri dish, trying to get to an area of 6 percent oxygen, which they like. It's a laboratory phenomenon." Copyright UC Regents

Keyword: Chemical Senses (Smell & Taste)
Link ID: 5780 - Posted: 06.24.2010

Brain implants have been used to "read the minds" of monkeys to predict what they are about to do and even how enthusiastic they are about doing it. It is the first time such high level cognitive brain signals have been decoded and could ultimately lead to more natural thought-activated prosthetic devices for people with paralysis, says Richard Andersen project leader at the California Institute of Technology, in Pasadena, US. By decoding the signals from 96 electrodes in a region of the brain just above the ear – called the parietal cortex - the researchers were able to predict 67 per cent of the time where in their visual field trained monkeys were planning to reach. They also found that this accuracy could be improved to about 88 per cent when the monkeys expected a reward for carrying out the task. The team were even able to predict what sort of reward the monkeys were expecting - whether it was juice or just plain water – from their brain signals. "In the future you could apply this cognitive approach to language areas of the brain," says Andersen. By doing so it may be possible to decode the words someone was thinking, he says. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 5779 - Posted: 06.24.2010

Contrary to popular belief, people in east Asia are no more genetically susceptible to short-sightedness than any other population group, according to researchers who have analysed past studies of the problem. The epidemics of myopia in countries such as Singapore and Japan are due solely to changes in lifestyle, they say, and similar levels could soon be seen in many western countries as lifestyles there continue to change. "As kids spend more time indoors, on computers or watching telly, we are going to become just as myopic," says Ian Morgan of the Australian National University in Canberra. Myopia is on the increase in most places, but in countries such as Singapore it has reached extraordinary levels. There, 80 per cent of 18-year-old male army recruits are myopic, up from 25 per cent just 30 years ago. Employers such as the police are having problems finding people who meet their requirements. There is also an increasing incidence of extreme myopia, which can lead to blindness. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 5778 - Posted: 06.24.2010

DURHAM, N.C. -- Researchers at Duke University Medical Center have provided the first direct evidence in mice for the role of an enzyme that specifically controls the production of serotonin in the brain. Different versions of that serotonin enzyme have a major effect on brain levels of the chemical messenger, which has been linked to many basic behavioral and physiological functions including mood, emotion, sleep and appetite, the researchers reported in the July 9, 2004, issue of Science. The finding has major implications for understanding psychiatric disorders and their treatment, the researchers said. Serotonin is a "neurotransmitter," a chemical that one neuron uses to trigger a nerve impulse in its neighbors. Thus, serotonin levels can profoundly affect brain function, and therefore behavior. "For the first time, we've identified a naturally occurring genetic difference that controls the production of serotonin in the brain," said Howard Hughes Medical Institute investigator Marc Caron, Ph.D., James B. Duke professor of cell biology at Duke and senior author of the study. The finding in mice sets the stage for new insights into the role the serotonin enzyme and the gene that encodes it might play in animal behavior and human psychiatric disorders, said the researchers. Low levels of serotonin have been implicated in many disorders such as depression, anxiety, post-traumatic stress disorder and attention deficit hyperactivity disorder. © 2001-2004 Duke University Medical Center.

Keyword: ADHD; Depression
Link ID: 5777 - Posted: 06.24.2010

Mpdz gene's discovery could someday lead to addiction-reducing therapy PORTLAND, Ore. -- One of the genes that influences drug physical dependence and associated withdrawal has been identified at Oregon Health & Science University. The gene, Mpdz, is involved in physical dependence on a class of drugs known as sedative-hypnotics, which are widely used for their euphoric and sedative effects. Drugs in this class include alcohol, inhalants, barbiturates, benzodiazepines, like Rohypnol or "roofies," and some other "club drugs." Scientists in the Portland Alcohol Research Center (PARC) and the Department of Behavioral Neuroscience, OHSU School of Medicine, found Mpdz using mice bred to possess a region of a chromosome known to be associated with a predisposition to physical dependence and withdrawal from sedative-hypnotics like alcohol and barbiturates. During the four-year search, the scientists narrowed the initial field of more than 1,000 candidate genes to only five genes, and finally to one. "We know that a host of biological and environmental factors interact in a complex manner throughout the addictive process to influence drug use or abuse. We think that physical dependence on sedative-hypnotic drugs and associated withdrawal episodes constitutes a motivational force that perpetuates drug use or abuse and contributes to relapse," said Nikki Walter, research associate in behavioral neuroscience and a study co-author.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 5776 - Posted: 07.09.2004

FALMOUTH, Maine - Just before summer vacation began last month, the playground at Plummer-Motz Elementary School was filled with hordes of children swinging on tires, running one another ragged around a large dirt field, and darting in and out of a wooden castle called the "maze craze." Jan Rankowski was not among them. The 9-year-old, diagnosed five years ago with Asperger Syndrome, a neurological disorder similar to autism that causes him to misunderstand the social world, was climbing on a jungle gym in his front yard. In November, after a string of complaints about what school officials said was aggressive and rude behavior, they banned Jan, who is home-schooled but spent recess with the other children, from the playground. The officials told the third-grader's parents not to bring him back until they allowed Jan to undergo an extensive evaluation known in educational parlance as a Functional Behavioral Assessment. Jan's parents, Charles Rankowski and Gayle Fitzpatrick, sued the school, charging discrimination. School officials say prohibiting Jan from going to the playground was necessary to Copyright 2004, azcentral.com.

Keyword: Autism
Link ID: 5775 - Posted: 07.09.2004

By RICK CALLAHAN, ASSOCIATED PRESS WRITER INDIANAPOLIS -- Rats fed artificial sweeteners ate three times the calories of rats given sugar, a finding the study's authors said suggests sugar-free foods may play a role in the nation's obesity epidemic. Other scientists, however, dismissed that conclusion, saying studies on people don't indicate that. One researcher called the rat study nonsense. The experiment by Purdue University researchers appears in the July issue of the International Journal of Obesity. The scientists said their rodent findings could help explain why Americans have grown fatter over the past two decades even as the nation's consumption of artificially sweetened sodas and snack foods has soared. They contend that artificial sweeteners could be interfering with people's natural ability to regulate how much they eat by distinguishing between high- and low- calorie sweets. As part of their study, they fed two groups of rats sweet-flavored liquids for 10 days. One group got only sugar-sweetened liquids, while the other was fed liquids sweetened by both sugar and saccharin. ©1996-2004 Seattle Post-Intelligencer

Keyword: Obesity
Link ID: 5774 - Posted: 06.24.2010

Researchers are to examine whether vaccinations play a part in the development of autism. A Bristol University team will also examine the possible impact of problems with birth, diet, infections and exposure to toxins. They will also test the theory that other conditions, such as coeliac disease, may increase the risk. More than 500,000 people in the UK are estimated to be affected by autism spectrum disorders. The condition affects the way people communicate and relate to people around them and sufferers have problems with everyday social interaction. They have a limited ability to develop friendships and find it hard to understand other people's emotional feelings. The incidence of the condition appears to have risen sharply over the last 30 years. However, nobody knows why this is, and it is possible that more cases are simply being diagnosed than in the past. Some scientists have suggested the MMR jab may be linked to autism. However, no research has ever proved a link, and the overwhelming majority of experts believe the vaccine is safe. The new research will be based on data generated from 14,000 children already taking part in the Children of the 90s study - a long-term project to examine the role of environment and genes on children's health. Lead researcher Professor Jean Golding said: "Because of the number of children we'll be looking at, and the quality and type of data available, our study should help find the answers to a number of currently unanswered questions about the environmental risks for developing autism spectrum disorders. (C)BBC

Keyword: Autism
Link ID: 5773 - Posted: 07.08.2004