- Researchers at UT Southwestern Medical Center have discovered that a protein associated with causing neurodegenerative conditions may, when appearing in normal amounts, actually protect against neurodegeneration. The findings, appearing in today's issue of the journal Cell, have surprised the researchers, because an excess of the same specific protein - alpha-synuclein - causes Parkinson's disease. "It's the first time that anyone has shown that synuclein has any positive function at all in the body, and this is important because it's been known to be involved in neurodegeneration," said Dr. Thomas Südhof, senior author of the study and director of the Center for Basic Neuroscience. Dr. Südhof also is an investigator in the Howard Hughes Medical Institute. The key to their findings was determining the interaction between alpha-synuclein and another protein - cysteine-string-protein-alpha, or CSP-alpha. The researchers' investigation involved several strains of mutant mice, which produced differing amounts of CSP-alpha or alpha-synuclein. Copyright 2005. The University of Texas Southwestern Medical Center at Dallas

Keyword: Parkinsons
Link ID: 8114 - Posted: 11.04.2005

If you show someone a mouse and a cat and ask which is smaller, they'll quickly reply, "the mouse." Ask which is bigger, and it takes most people slightly longer to respond. Conversely, if the two animals are large, such as a cow and an elephant, the typical person will be quicker at saying the elephant is larger than saying the cow is smaller. This rule, known to scientists from actual tests on people, is known as "semantic congruity," and it also holds true for comparing numbers and distances. Until now, scientists thought the rule was rooted in our language abilities. But in a recent study by researchers at Duke University, a group of monkeys have shown a similar ability to tell the difference between large and small groups of dots. Researchers showed macaque monkeys two arrays of randomized numbers of dots on a computer touch screen. Instead of asking the monkeys to choose the larger or smaller array of dots, the researchers gave cues by changing the color of the background behind the dots. © 2005 MSNBC.com

Keyword: Intelligence; Evolution
Link ID: 8113 - Posted: 06.24.2010

Making creatures do what we want at the flick of a switch sounds more like Frankenstein than real science, but scientists have discovered that using a laser, they can make headless fruit flies (Drosophila melanogaster) jump, flap their wings and fly on command. But Yale University neurologist Gero Miesenboeck and his team weren't out just to create remote-controlled insects. They hoped to study nerve-cell activity and connections, and learn how nerve cell circuits process information related to specific behaviors — from simple movements to more complex behaviors like learning, aggression and even abstract thoughts, like how they understand notions of punishment and reward. "The nervous system is simple enough to raise hopes that we can actually some day understand how it works and yet it's complex enough to produce really, really interesting behaviors," Miesenboeck says. "Now it is possible to control specific groups of nerve cells." He says controlling specific nerve cells (neurons) may reveal what's behind behaviors that some of us want to stop. — matching specific cells to behaviors, scientists may one day be able to use optics like this to create drugs that target undesirable behavior, such as overeating. © ScienCentral, 2000-2005.

Keyword: Miscellaneous
Link ID: 8112 - Posted: 06.24.2010

About five million Germans have serious learning difficulties when it comes to reading and writing. It is frequently the case that several members of the same family are affected. So hereditary disposition seems to play an important role in the occurrence of dyslexia. Scientists at the universities of Marburg, Würzburg and Bonn have been working on this question together with Swedish colleagues from the Karolinska Institute in Stockholm. In examinations of German children with serious reading and writing difficulties they have now succeeded in demonstrating for the first time the contribution of a specific gene. Precisely how it contributes to the disorder remains unclear. It is thought that the genes may affect the migration of nerve cells in the brain as it evolves. The results will be published in the January edition of the American Journal of Human Genetics, but have already been made available online (http://www.journals.uchicago.edu/AJHG). For several years child and youth psychologists at the universities of Marburg and Würzburg searched for families in which at least one child was considered dyslexic. "We then analysed blood samples taken from the families to identify candidate genes – and in the end we found the right one," explains the scientist who headed this part of the study from Marburg, Privatdozent Dr. Gerd Schulte-Körne.

Keyword: Dyslexia; Genes & Behavior
Link ID: 8111 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Bird wealth is measured in food, not money, and researchers have discovered that berry-rich bluebird young with edible inheritances prefer to stay in the nest. Since humans and many other animals also often stay close to home when the pickings are good, the discovery supports the theory that wealth can promote family stability and togetherness. The study, which will be published later this year in The Proceedings of the Royal Society B, focused on Western bluebirds, Sialia mexicana, which live in California. While bluebird daughters usually flew away from home at the expected time in August, bluebird sons stayed with their parents all the way through winter when desired mistletoe berries were plentiful. When the sons finally decide to leave home to breed, they often do not go far and still may reap familial benefits, including meeting females that their parents might know. © 2005 Discovery Communications Inc.

Keyword: Sexual Behavior; Evolution
Link ID: 8110 - Posted: 06.24.2010

By Rossella Lorenzi, Discovery News — Elephants pay homage to the bones of their dead, gently touching the skulls and tusks with their trunks and feet, according to the first systematic study of elephant empathy for the dead. The finding provides the first hard evidence to support stories of elephant mourning, in which the pachyderms are said to congregate at elephant cemeteries, drawn by the bones of their kin. It also shows that these animals display a trait once thought to be unique to humans, said Karen McComb, an expert on animal communication and cognition at the University of Sussex in Brighton, England. "Most mammals show only passing interest in the dead remains of their own or other species," McComb and colleagues wrote in the current issue of the Royal Society journal Biology Letters. Lions are typical in this respect: they briefly sniff or lick a dead of their own species before starting to devour the body. Chimpanzees show more prolonged and complex interactions with dead social partners, but leave them once the carcass starts decomposing. © 2005 Discovery Communications Inc.

Keyword: Intelligence; Evolution
Link ID: 8109 - Posted: 06.24.2010

Andreas von Bubnoff The inflamed mammary glands of sheep have been found to contain protein particles that cause scrapie, a sickness similar to mad cow disease. This suggests that the suspect proteins, called prions, may also be present in the milk of infected animals. If prions exist in the milk of cows infected with both an inflammatory illness and mad cow disease, formally known as bovine spongiform encephalopathy (BSE), this raises concerns for human health. Consumption of prion-contaminated meat from cows with BSE is believed to cause the fatal variant Creutzfeldt-Jakob disease (vCJD) in people; so might contaminated milk. Adriano Aguzzi, the lead researcher on the study, has not detected prions in milk itself, because it is difficult to analyse for the abnormal proteins. But he says he expects to find them. "It is unlikely that the prions are not in the milk," says Aguzzi, a pathologist at the University of Zurich Hospital, Switzerland. "And the prospect is not a pleasant one." ©2005 Nature Publishing Group

Keyword: Prions
Link ID: 8108 - Posted: 06.24.2010

A new pathway for treating multiple sclerosis may have been found, if “exciting” results in mice can be replicated in humans. MS is an incurable degenerative disease caused by the body’s immune system attacking the protective myelin sheath encasing the nerves that make up the central nervous system. The nerve fibres become increasingly damaged by scar tissue, known as sclerosis, which leads to paralysis and loss of speech and vision. But researchers trying a novel therapy on a mouse version of MS report that the mice showed “almost no inflammation of the myelin sheath and no nerve damage”. Furthermore, MS is characterised by periods of remission and relapse, but the mice recovered with fewer and far less severe relapses. The therapy targets immune system cells called T-cells. These malfunction in MS patients, producing inflammatory molecules that destroy the myelin sheath. The new treatment, which uses a class of molecules called kynurenines, works by inhibiting the T-cells’ production of inflammatory molecules and prompting them to produce agents that “mop up” the molecules. © Copyright Reed Business Information Ltd.

Keyword: Multiple Sclerosis
Link ID: 8107 - Posted: 06.24.2010

Howard Hughes Medical Institute (HHMI) researchers have deciphered a key part of the regulatory code that governs how motor neurons in the spinal cord connect to specific target muscles in the limbs. The researchers said that understanding this code may help guide progress in restoring motor neuron function in people whose spinal cords have been damaged by trauma or disease. The studies suggest that the code — which involves members of the family of transcription factors encoded by the Hox genes — could also govern the establishment of other spinal cord circuits. This circuitry includes interneurons that control motor neuron firing patterns and sensory neurons that transmit feedback information on muscle action. The research team, which was led by HHMI investigator Thomas M. Jessell, published its findings in the November 4, 2005, issue of the journal Cell. Jessell collaborated on the studies with HHMI research associate Jeremy S. Dasen, Bonnie C. Tice and Susan Brenner-Morton, all of whom are at Columbia University. The work was also funded by grants from the National Institute of Neurological Disorders and Stroke and Project ALS. According to Jessell, members of the Hox gene family had been known to regulate aspects of brain development, but “few people had paid attention to the fact that these genes are also expressed in the spinal cord.” Earlier work performed by Dasen and Jessell, in collaboration with Jeh-Ping Liu, who is now at the University of Virginia, established that certain Hox proteins control the differentiation of motor neurons into columns in the spinal cord. These columns, which are arrayed along the anterior-posterior length of the spinal cord, form in the initial phases of motor neuron organization. That organization determines whether motor neurons grow to the limbs or to other targets. © 2005 Howard Hughes Medical Institute.

Keyword: Development of the Brain
Link ID: 8106 - Posted: 06.24.2010

Women with high levels of the sex hormone oestrogen have prettier faces, research suggests. The findings make evolutionary sense - men are attracted to the most fertile women, the University of St Andrews team told a Royal Society journal. Oestrogen levels during puberty can impact on appearance by affecting bone growth and skin texture, they said. But make-up masks this effect, allowing less attractive women to compensate for their lack of natural mating cues. The team of psychologists at the University's Perception Lab photographed 59 young women's faces aged between 18 and 25 and analysed their sex hormone levels. They then asked 30 volunteers - 15 male and 15 female - to rate the faces according to attractiveness. Both male and female volunteers rated the faces of the women with the highest hormone levels as the most attractive. These faces tended to have classically feminine features, such as larger eyes and lips and smaller noses and jaws. However, when the women in the photographs were wearing make-up, no relationship between attractiveness and oestrogen was found. The researchers believe that, while make-up improves facial appearance, it may be masking cues normally seen in the face. Head of the study, Miriam Law Smith, said: "Women are effectively advertising their general fertility with their faces. (C)BBC

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 8105 - Posted: 11.03.2005

Scientists have found that the tongue has taste receptors for fat, which might explain why we like fried foods. Conventionally, experts have thought that the tongue detects five tastes - sweet, salty, sour, bitter and umami taste for protein rich foods. But tests on rodents showed a receptor on the tongue tastes fat - it is not known if it is the same for humans. The work by French researchers from the University of Burgundy appears in the Journal of Clinical Investigation. Investigator Philippe Besnard and his team believe the CD36 receptors that they found were important for evolutionary reasons - to ensure animals ate a high energy diet when foods were scarce. But in the current Western climate, where food is in abundance and about 40% of the energy we consume comes from fat, this may be a disadvantage for the waistline if the same receptor is present in humans. The CD36 receptor is already known to exist in many tissues involved in fat storage. To see whether the receptor might be the tongue's fat detector, the researchers studied rats and mice that were normal or had the gene for CD36 "knocked out" so that the receptor no longer worked. The normal rodents showed a preference for fatty foods when offered them, yet the knock out mice did not. Also, when the researchers put a fatty liquid onto the tongues of the normal rats, this triggered a release of fat-processing substances from the digestive organs. This reaction did not happen in the knock out mice. (C)BBC

Keyword: Chemical Senses (Smell & Taste); Obesity
Link ID: 8104 - Posted: 11.03.2005

AUSTIN, Texas--Neurons experience large-scale changes across their dendrites during learning, say neuroscientists at The University of Texas at Austin in a new study that highlights the important role that these cell regions may play in the processes of learning and memory. The research, published online Oct. 23 and in the November issue of the journal Nature Neuroscience, shows that ion channels distributed in the dendritic membrane change during a simulated learning task and that this requires the rapid production of new proteins. "Our new work strongly supports the idea that learning involves changes in dendrites," says Dr. Daniel Johnston, director of the Center for Learning and Memory and professor in the Institute for Neuroscience. The finding could also lead to advances in understanding conditions like epilepsy and age-related memory loss and could point to potential treatment opportunities for such conditions in the future. Dendrites--the thin branch-like extensions of a neuron cell--receive many inputs from other neurons that transmit information through contact points called synapses. Much attention has been focused on the role that changes at synapses play in learning. They change in ways that make it easier for connected neurons to pass information.

Keyword: Learning & Memory
Link ID: 8103 - Posted: 11.03.2005

Symptoms, like difficultly sounding out words, make dyslexia readily detectable. But the causes of the disability are still hard to pinpoint. "Why? What causes these otherwise very bright children to struggle to read?" asks pediatrician Sally Shaywitz, co-director of Yale University's Center for the Study of Learning and Attention, and the author of "Overcoming Dyslexia." "Dyslexia is an unexpected difficulty first in learning to read, and then in having to struggle to read," she explains. "That means the person who is dyslexic has all the factors present that say, 'This person should be a good reader. They're intelligent, they're motivated, and they've had good education. Yet they still struggle to read." If left untreated, childhood dyslexia becomes an adult problem. "It's not something that's outgrown," says neurophysiologist Lynn Flowers from Wake Forest University Baptist Medical Center. "Ten percent of the child and therefore the adult population is affected by dyslexia to some degree," she says. "It isn't an all or nothing kind of disorder, it comes in shades as well." © ScienCentral, 2000-2005.

Keyword: Dyslexia
Link ID: 8102 - Posted: 06.24.2010

As any chef at a greasy spoon can attest, humans have a taste for fatty foods. Now, scientists may know why. Researchers have found a new receptor on mice and rat tongues that detects fat and helps prepare the body to digest it. The results may help explain why some people crave fat more than others and could help researchers uncover new ways to fight obesity. It's long been clear that humans and rodents taste sweet, sour, bitter, salty, and protein-rich foods, but researchers thought we sensed the fat in food by its smell and creamy texture. Over the past decade or so, however, results have dribbled in suggesting we--or at least mice and rats--taste fats. In one study, applying a chemical to the tongue that blocks a fat-digesting enzyme prevented rats and mice from tasting fats and fatty acids, a breakdown product of fats. Intrigued, physiologist Philippe Besnard of the University of Bourgogne in Dijon, France, and colleagues focused on a fatty-acid receptor called CD36 that's found in fat and other tissues. After chemically linking a red fluorescent dye to antibodies that bound CD36, the researchers showed that taste buds glowed red, indicating that CD36 was in the right place to do the job. To see if animals use CD36 to taste fats, the team bred a line of mice that lacked the receptor. When given a choice between their standard fare and fat-enriched treats, normal mice consumed 3 times as much of the junk food, but mutant mice showed no preference, presumably because they couldn't taste the difference. © 2005 by the American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 8101 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — As women experience their regular menstrual cycle, they undergo bodily changes that can cause emotional mood swings, but scientists have just discovered that women without problems associated with PMS have brains that can regulate the cyclical emotional overloads. The study, published in a recent Proceedings of the National Academy of Sciences, represents the first time that PMS (Premenstrual Syndrome) has been studied using functional MRI brain scanning, along with tests designed to probe emotional changes. The findings suggest that PMS and more serious symptoms associated with menstruation are driven by forces that may be beyond a woman's control. "In the past, many women suffering from PMS were told to, 'Just get over it,' or were asked, 'Why can't you handle this?'" said David Silbersweig, one of the study's authors. Silbersweig, a physician and researcher at Cornell University's Weill Medical College, added, "We now hope that our research will help the public to understand that PMS can involve changes in the brain, and that the condition is not just psychological, but that biological systems are involved that help to control emotions and behavior." © 2005 Discovery Communications Inc.

Keyword: Hormones & Behavior; Emotions
Link ID: 8100 - Posted: 06.24.2010

By Beth Baker Special to The Washington Post In 2001, Ellen Proxmire faced a tough decision regarding her husband -- William Proxmire, the former Democratic senator. Diagnosed seven years earlier with Alzheimer's disease, he frequently wandered from home. He even managed to escape from a locked hospital unit. When he represented Wisconsin from 1957 to 1989, Proxmire had a reputation as a maverick. But the independent streak prized in a politician was dangerous in a person living with Alzheimer's disease. One day he eluded the caregiver hired to keep an eye on him at the Library of Congress, where he still enjoyed a private carrel. Hours later he was found walking on the Southeast Freeway. Someone recognized him and picked him up and brought him home, his wife said. Much as she hated to admit it, Ellen Proxmire knew she could no longer care for her husband at home. She visited some 20 Alzheimer's residential facilities in the Washington area and in Arizona, where she hoped to live. Even those with good reputations she found dismal. "People were drugged and sitting in a corner, tied to chairs," she said. "And there are some places who don't want someone who is difficult." © 2005 The Washington Post Company

Keyword: Alzheimers
Link ID: 8099 - Posted: 06.24.2010

HOUSTON --- Visual information can be processed unconsciously when the area of the brain that records what the eye sees is temporarily shut down, according to research at Rice University in Houston. The research, published the week of Oct. 31 in the Proceedings of the National Academy of Sciences' (PNAS) online Early Edition, suggests the brain has more than one pathway along which visual information can be sent. For the study, the researchers induced temporary, reversible blindness lasting only a fraction of a second in nine volunteers with normal vision. Transcranial magnetic stimulation (TMS), a harmless noninvasive technique using brief magnetic pulses, was applied to the volunteers' visual cortex -- the area at the back of the brain that processes what the eye sees - to interrupt the normal visual pathway. The volunteers looked at a computer screen, and during their momentary blindness, either a horizontal or a vertical line or a red or a green dot flashed on the screen. Researchers then asked the study participants whether they had seen a horizontal or a vertical line; because their primary visual pathway had been shut down, the participants reported that they saw nothing. However, when forced to guess which line had appeared on their computer screen, the participants gave the correct answer 75 percent of the time. When the participants had to guess whether a red or a green dot had flashed on the screen, they gave the correct answer with 81 percent accuracy.

Keyword: Vision
Link ID: 8098 - Posted: 11.01.2005

By Jason Feifer From across the apartment, my girlfriend smelled smoke. "Is something burning?" she called to me in the kitchen. No, everything's fine, I yelled back. A few minutes later, she came in to investigate. She found me washing dishes, oblivious to the smoking George Foreman grill beside me. "You're so dying in a fire," she said as she yanked the plug from the wall. I don't know why I didn't see the smoke, but there was good reason I didn't smell it. Like an estimated 14 million Americans, I suffer from smell loss. Like a smaller number of them, I can't taste, either. I can occasionally appreciate a flower's aroma or food's flavor, but only vaguely and superficially. My imagination helps fill in the blanks; but when I'm blindfolded, I confuse mint ice cream and peanut butter ice cream. My girlfriend, who has the olfactory capabilities of a bloodhound, has run me through this test numerous times. She, like most everyone else I tell about this, simply cannot understand my experience. I have a hard time explaining it myself. It's as if my tongue and nose can sense differences -- water tastes different from juice, say, and unscented air smells different from perfume -- but the differences are faint and forgettable, and I have no ability to identify them. Chocolate is strawberry is scrambled eggs. © 2005 The Washington Post Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 8097 - Posted: 06.24.2010

By ERIC NAGOURNEY Botox may do more than just get rid of wrinkles. In addition to providing relief from eye spasms and migraines, Botox, formally botulinum toxin A, has now been found useful in treating the intense facial pain called trigeminal neuralgia. In a study published in the Oct. 25 issue of Neurology, the drug provided partial or complete relief to all 13 patients tested. Until now, anticonvulsant drugs or neurosurgery have been the only treatments for the disorder. The drugs can have unpleasant side effects, and the surgery is expensive and carries risks. Neither treatment is universally effective. Dr. Stephen D. Silberstein, a co-author on the paper, said he would recommend Botox even though it had not been randomly tested in controlled clinical trials. "The purists would say you shouldn't do something not proven in a double-blind study," Dr. Silberstein said, referring to research in which one group is given the medicine and another group is given a placebo. "But the surgical alternatives are unproven procedures that are more expensive and more risky. I don't see any reason not to use it just because we don't have all the evidence in." The Botox treatment requires injections of 10 units four or five times a year. Botox costs about $5 a unit, according to Dr. Silberstein, who is a professor of neurology at Jefferson Medical College in Philadelphia. Copyright 2005 The New York Times Company

Keyword: Pain & Touch
Link ID: 8096 - Posted: 11.01.2005

Looking in a mirror at a reflection of their healthy hand could help people with persistent pain ease their symptoms and eventually overcome their problem, say scientists in the latest edition of the journal Clinical Medicine. The treatment, being developed by researchers from the University of Bath and the Royal National Hospital for Rheumatic Diseases (RNHRD), is based on a new theory about how people experience pain even when doctors can find no direct cause. This ‘cortical’ model of pain suggests that the brain’s image of the body can become faulty, resulting in a mismatch between the brain’s movement control systems and its sensory systems, causing a person to experience pain when they move a particular hand, foot or limb. Researchers believe that this kind of problem could be behind a host of pain-related disorders, such as complex regional pain syndrome and repetitive strain injury. In an investigation of whether this system can be corrected using mirrors to trick the brain, researchers asked a number of patients with complex regional pain syndrome (a chronic debilitating condition affecting 10,000 – 20,000 patients in the UK at any one time) to carry out routine exercises in front of a mirror. University of Bath © 2004

Keyword: Pain & Touch
Link ID: 8095 - Posted: 06.24.2010