Getting stressed now and again may be good for your health, research suggests. A short burst of stress, such as that caused by sitting an exam, may strengthen your body's immune system. But long-term stress, such as living with a permanent disability, may render you less able to fight infections, say the study authors. Dr Suzanne Segerstrom and Dr Gregory Miller report their findings in the journal Psychological Bulletin. Scientists have known for some time that stress can have a negative effect on the body. Now the American and Canadian pair from the University of Kentucky and the University of British Columbia say some psychological stress can be good for you. They looked at about 300 scientific papers published on the subject, involving almost 19,000 people. Stressful situations that lasted only short periods appeared to tap into the primeval 'fight or flight' response, which dates back to when early man was threatened by predators. This response benefited the person by boosting their body's natural front-line defence against infections from traumas such as bites and scrapes. But long-term anxiety had the opposite effect. (C)BBC

Keyword: Stress; Neuroimmunology
Link ID: 5752 - Posted: 07.05.2004

University of Iowa researchers have shown for the first time that gene therapy delivered to the brains of living mice can prevent the physical symptoms and neurological damage caused by an inherited neurodegenerative disease that is similar to Huntington's disease (HD). If the therapeutic approach can be extended to humans, it may provide a treatment for a group of incurable, progressive neurological diseases called polyglutamine-repeat diseases, which include HD and several spinocerebellar ataxias. The study, conducted by scientists at the UI Roy J. and Lucille A. Carver College of Medicine and colleagues at the University of Minnesota and the National Institutes of Health (NIH), appears in the August issue of Nature Medicine and in the journal's advanced online publication July 4. "This is the first example of targeted gene silencing of a disease gene in the brains of live animals and it suggests that this approach may eventually be useful for human therapies," said senior study author Beverly Davidson, Ph.D., the Roy J. Carver Chair in Internal Medicine and UI professor of internal medicine, physiology and biophysics, and neurology. "We have had success in tissue culture, but translating those ideas to animal models of disease has been a barrier. We seem to have broken through that barrier."

Keyword: Huntingtons; Movement Disorders
Link ID: 5751 - Posted: 07.05.2004

Clear patterns emerge outlining greater damage from chronic stress WASHINGTON — Psychologists have long known that stress affects our ability to fight infection, but a major new “meta-analysis” – a study of studies – has elucidated intriguing patterns of how stress affects human immunity, strengthening it in the short term but wearing it down over time. The report appears in the July issue of Psychological Bulletin, which is published by the American Psychological Association. Major findings are three-fold. First, the overlapping findings of 293 independent studies reported in peer-reviewed scientific journals between 1960 and 2001 – with some 18,941 individuals taking part in all -- powerfully confirm the core fact that stress alters immunity. Second, the authors of the meta-analysis observed a distinctive pattern: Short-term stress actually “revs up” the immune system, an adaptive response preparing for injury or infection, but long-term or chronic stress causes too much wear and tear, and the system breaks down. Third, the immune systems of people who are older or already sick are more prone to stress-related change. Psychologists Suzanne Segerstrom, PhD, of the University of Kentucky, and Gregory Miller, PhD, of the University of British Columbia, analyzed the results of the nearly 300 studies by sorting them into different categories and statistically evaluating relationships. For example, the five stressor categories included: © 2004 American Psychological Association

Keyword: Stress; Neuroimmunology
Link ID: 5750 - Posted: 06.24.2010

By Jennifer Quinn We know torture when we see it - the problem is those meting out the violence often don't. That's the revelatory conclusion of one expert who is attempting to understand the insidious way in which torture becomes "acceptable". It's called degradation, mistreatment, tough interrogation. According to experts, it's often called everything except what it is - torture. "In investigations of US abuse of imprisoned Iraqis, there has been reluctance to use the T-word," Martha Huggins, a sociology professor at New Orleans' Tulane University, told a forum on torture this week. And when governments, military organisations and police services refuse to label "tough interrogation" as torture, it creates an atmosphere where the mistreatment of prisoners is allowed to flourish. After studying Brazilian police from 1964 to 1985, Ms Huggins laid out the classic conditions for mistreatment of prisoners. As part of the American Association for the Advancement of Science's marking United Nations International Day in Support of Victims of Torture, she spoke to a Washington, DC, conference about them. The half-day forum also heard from physicians who treat people who have been tortured and the effects of torture and detention on the families of victims. The conference was staged less than two miles from the United States Supreme Court, where the justices were releasing a decision that said prisoners at Guantanamo Bay were entitled to challenge their custody through American courts. The issue of torture has dominated the news since photographs of prisoners at the US-controlled Abu Ghraib prison in Iraq came to light. (C)BBC

Keyword: Aggression
Link ID: 5749 - Posted: 07.03.2004

Every year, Independence Day brings a unique array of sights and an overload of sounds, with fireworks as the main culprit for both. But while most people are aware of the harm and damage a burning Roman candle can do if not handled properly, many aren't thinking about protecting their hearing on one of the noisiest days of the year. "It's quite possible for a person on the fourth of July to experience a dose of noise that's significant enough to cause hearing loss and ringing in their ears, due to an explosion very close to their ears possibly, or just a cumulative exposure over the day," says Robert Novak, professor of audiology and clinical director for the department of Audiology and Speech Sciences at Purdue University. David Sorensen, a Philadelphia attorney, can vouch for that. Every July 4th he's reminded of the summer he let freedom ring a little too loudly: "The summer after fourth grade, right around July 4th when there were a lot of fireworks in the neighborhood," Sorensen recalls. "I liked caps. And one day I smashed more than just a few at a time and I had a loud ringing in my ears." More than three decades later, that ringing still hasn't stopped, and has made everyday living difficult. "My goal is to have a quiet night's sleep," says Sorensen. © ScienCentral, 2000- 2004.

Keyword: Hearing
Link ID: 5748 - Posted: 06.24.2010

Anesthetics are slowly giving up the secrets of how they work John Travis Take a stroll through the Boston Public Garden, the nation's oldest botanical garden, and you'll find an array of plaques, monuments, and memorials honoring famous people of history. Not far from a statue of George Washington on horseback, there's a tall monument that honors not a person, but a chemical. This tribute to ether is probably the world's only monument to a drug. A statue representing the Good Samaritan tops the structure, which displays the inscription, "There shall be no more pain." Erected in the 19th century, the tribute commemorates ether's first use as a surgical general anesthetic, which took place in 1846 at the Massachusetts General Hospital in Boston. Today, it's hard to imagine what surgery was like before this discovery and the subsequent development of inhaled and injected chemicals that are even more effective in rendering people unconscious and insensitive to pain. General anesthesia has a "magical quality to it," says anesthesiologist James Sonner of the University of California, San Francisco. "It was and still is amazing that you can . . . make an organism comatose, unresponsive enough to perform surgery, and reverse the whole thing." Copyright ©2004 Science Service

Keyword: Pain & Touch
Link ID: 5747 - Posted: 06.24.2010

People who have early stage Alzheimer's disease (AD) could be more capable of learning than previously thought, according to two new studies supported by the National Institute on Aging (NIA), a part of the National Institutes of Health. The promising studies suggest that some people with early cognitive impairment can still be taught to recall important information and to better perform daily tasks. In a July 2004 report, researchers in Miami, FL, found mildly impaired AD patients who participated in 3-to-4 months of cognitive rehabilitation had a 170 percent improvement, on average, in their ability to recall faces and names and a 71 percent improvement in their ability to provide proper change for a purchase. The participants also could respond to and process information more rapidly and were better oriented to time and place compared to a similar group of AD patients who did not receive this targeted intervention. These improvements were still evident 3 months after the cognitive training ended. The findings, by David A. Loewenstein, Ph.D., and colleagues at the University of Miami School of Medicine and Mount Sinai Medical Center, Miami Beach, are reported in the July-August 2004 issue of the American Journal of Geriatric Psychiatry. The Loewenstein report follows a recent study by researchers at Washington University in St. Louis who found that older people with early-stage AD retained functioning levels of implicit memory similar to young adults and older adults who did not have AD. Implicit memory is relatively unconscious and automatic: Information from the past "pops into mind" without a deliberate effort to remember. This unconscious, implicit memory is important for common skills and activities, such as speaking a language or riding a bicycle.

Keyword: Alzheimers; Learning & Memory
Link ID: 5746 - Posted: 07.03.2004

Scientists have shown how the brain can be fooled into feeling sensations in a fake limb. They recorded changes in brain activity during an experiment in which volunteers were made to think a rubber hand was their own limb. The University College London team hope their work will shed light on self-perception disorders such as schizophrenia and stroke. Their work is published in Science Express Online. In the study, funded by the Wellcome Trust, volunteers hid their right hand under a table and a rubber hand was put in front of them at an angle to make it look like part of their body. The rubber hand and hidden real hand were stroked simultaneously with a paintbrush while the volunteer's brain was scanned using magnetic resonance imaging. It took just 11 seconds for volunteers to start feeling the rubber hand was their own. The stronger the feeling, the greater the activity recorded in the brain. Volunteers were later asked to point towards their right hand. Most pointed towards the rubber hand instead of the real one, showing how the brain had readjusted. The researchers found one area of the brain, called the premotor cortex, recognises the body by accepting information from three different senses - vision, touch and proprioception (position sense).

Keyword: Pain & Touch
Link ID: 5745 - Posted: 07.02.2004

As the evidence accumulates for epigenetics, researchers reacquire a taste for Lamarckism By Leslie A. Pray Toward the end of World War II, a German-imposed food embargo in western Holland--a densely populated area already suffering from scarce food supplies, ruined agricultural lands, and the onset of an unusually harsh winter--led to the death by starvation of some 30,000 people. Detailed birth records collected during that so-called Dutch Hunger Winter have provided scientists with useful data for analyzing the long-term health effects of prenatal exposure to famine. Not only have researchers linked such exposure to a range of developmental and adult disorders, including low birth weight, diabetes, obesity, coronary heart disease, breast and other cancers, but at least one group has also associated exposure with the birth of smaller-than-normal grandchildren.1 The finding is remarkable because it suggests that a pregnant mother's diet can affect her health in such a way that not only her children but her grandchildren (and possibly great-grandchildren, etc.) inherit the same health problems. In another study, unrelated to the Hunger Winter, researchers correlated grandparents' prepubertal access to food with diabetes and heart disease.2 In other words, you are what your grandmother ate. But, wait, wouldn't that imply what every good biologist knows is practically scientific heresy: the Lamarckian inheritance of acquired characteristics? If agouti mice are any indication, the answer could be yes. The multicolored rodents make for a fascinating epigenetics story, which Randy Jirtle and Robert Waterland of Duke University told last summer in a Molecular and Cell Biology paper; many of the scientists interviewed for this article still laud and refer to that paper as one of the most exciting recent findings in the field. The Duke researchers showed that diet can dramatically alter heritable phenotypic change in agouti mice, not by changing DNA sequence but by changing the DNA methylation pattern of the mouse genome.3 "This is going to be just massive," Jirtle says, "because this is where environment interfaces with genomics." © 2004, The Scientist LLC, All rights reserved.

Keyword: Genes & Behavior; Development of the Brain
Link ID: 5744 - Posted: 06.24.2010

The Saharan desert ant (Cataglyphis fortis) takes no chances when it comes to homeland security. It viciously attacks ants from other colonies that get too close to its nest. Now researchers have found that the ant relies on the same internal navigation system it uses for foraging to decide whether an intruder has come too close for comfort. Many animals fly into a defensive rage when they sense competitors edging in on their territory. But in the sandy Sahara, few environmental cues mark territorial boundaries. Behavioral neurobiologists Markus Knaden and Rüdiger Wehner of the University of Zürich in Switzerland wondered whether the sight or smell of the nest primes the ants for a fight or if their internal navigation system puts them on alert. Previous research showed that the desert ants somehow keep track of every step and turn they take when out foraging for food and integrate that information to plot a straight line back home. The system apparently serves the ants well, enabling them to find their way in an environment devoid of landmarks and get back to the nest before shriveling up in the hot sun. To test whether the ants' navigation system also plays a role in aggression, Knaden and Wehner placed a feeder 20 meters from a desert ant nest. Left undisturbed, the ants snatched a bite of food and ran straight back to their nest. But the researchers grabbed the ants as soon as the ants picked up a piece of food and moved them to a 40-meter-square grid 2 kilometers away. There, they turned the ants loose and let them run either 20 meters or only 5 meters before testing their willingness to fight other ants. The ants that ran the whole 20 meters--covering what would have been the distance back to their nest--were far more aggressive than the ones that only ran 5, the team reports in the 2 July issue of Science.

Keyword: Aggression
Link ID: 5743 - Posted: 07.02.2004

ITHACA, N.Y. -- A laser-based microscopy technique may have settled a long-standing debate among neuroscientists about how brain cells process energy -- while explaining what's really happening in PET (positron emission tomography) imaging and offering a better way to observe the damage that strokes and neurodegenerative diseases, such as Alzheimer's, wreak on brain cells. Multi-photon microscopy scans by Cornell University biophysicists of living brain tissue, as reported in the latest issue of Science (July 2, 2004), reveal exactly how and when neurons (the cells that do the thinking) and astrocytes (the starburst-shaped glial cells that service neurons) interact to burn oxygen and glucose, after astrocytes make lactate from glucose in the bloodstream, to meet the extraordinary energy demands of the brain. Based on imaging of two different energy states of NADH (nicotinamide adenine dinucleotide, a coenzyme involved in brain-cell metabolism), the Cornell biophysicists say they have both confirmed and redefined the controversial "astrocyte-neuron lactate shuttle" hypothesis for brain energy metabolism. "Over the past decade scientists have passionately debated whether the activated brain burns glucose completely to water or incompletely to lactate," said Karl A. Kasischke, M.D., lead author of the Science paper titled "Neural Activity Triggers Neuronal Oxidative Metabolism Followed by Astrocytic Glycolysis."

Keyword: Glia
Link ID: 5742 - Posted: 07.02.2004

The remnants of a remarkably petite skull belonging to one of the first human ancestors to walk on two legs have revealed the great physical diversity among these prehistoric populations. But whether the species Homo erectus, meaning "upright man", should be reclassified into several distinct species remains controversial. Richard Potts, from the National Museum of Natural History at the Smithsonian Institute in Washington, DC, and colleagues discovered numerous pieces of a single skull in the Olorgesailie valley, in southern Kenya, between June and August 2003. The bones found suggest the skull is that of a young adult Homo erectus who inhabited the lush mountainside some 930,000 years ago. The prominent brow and temporal bone resemble other Homo erectus specimens found elsewhere in Africa, and in Europe, Indonesia and China. But the skull itself is around 30% smaller, which is likely to have corresponded to a similar difference in body size. The specimen helps fill a gap in the fossil record as very few Homo erectus specimens of this age have been found in Africa so far. © Copyright Reed Business Information Ltd.

Keyword: Evolution
Link ID: 5741 - Posted: 06.24.2010

Scientists have made the first recordings of the human brain's awareness of its own body, using the illusion of a strategically-placed rubber hand to trick the brain. Their findings shed light on disorders of self-perception such as schizophrenia, stroke and phantom limb syndrome, where sufferers may no longer recognize their own limbs or may experience pain from missing ones. In the study published today in Science Express online, University College London's (UCL) Dr Henrik Ehrsson, working with Oxford University psychologists, manipulated volunteers' perceptions of their own body via three different senses - vision, touch and proprioception (position sense). They found that one area of the brain, the premotor cortex, integrates information from these different senses to recognize the body. However, because vision tends to dominate, if information from the senses is inconsistent, the brain "believes" the visual information over the proprioceptive. Thus, someone immersed in an illusion would feel, for example, that a fake limb was part of their own body. In the study, each volunteer hid their right hand beneath a table while a rubber hand was placed in front of them at an angle suggesting the fake hand was part of their body. Both the rubber hand and hidden hand were simultaneously stroked with a paintbrush while the volunteer's brain was scanned using functional magnetic resonance imaging.

Keyword: Pain & Touch
Link ID: 5740 - Posted: 07.02.2004

BY JAMIE TALAN Almost one in every six soldiers arriving home from duty in Iraq is showing symptoms of post-traumatic stress disorder, depression or anxiety, according to interviews with more than 6,000 soldiers and Marines before and after deployment. Many said they were aware of their symptoms, but few have sought help. According to the study, published in today's New England Journal of Medicine, the veterans cited fear of the stigma of mental illness - that it could cost them their careers or alter relationships with peers and command officers. "These findings cry out for creative solutions," said Dr. Matthew Friedman, executive director of the Department of Veterans Affairs National Center for PTSD. "We need to figure out ways to get these people into treatment." Post-traumatic stress disorder - once known as shell shock or combat fatigue - was the most reported mental health problem. Overall, about 12 percent of those returning from Iraq reported symptoms, compared to 3 percent to 4 percent of the general population. Copyright © 2004, Newsday, Inc.

Keyword: Stress
Link ID: 5739 - Posted: 06.24.2010

NEW ORLEANS - After seven months of constant, bark-like hiccups, a first-of-its-kind operation has returned normal life to a 50-year-old Texas man. Shane Shafer's speech is now a hoarse whisper — a side effect of the electronic device that cured him, one generally used to treat epilepsy and recently approved for major depression. But for the first time since November, he can eat. He can sleep. He no longer has to make himself gag to make the hiccups stop. He can talk without a bark-like hiccup every three to four seconds. "Even something as simple as a kiss is now performed without a hiccup," said his wife, Lori Shafer. Surgeons implanted the device — a "vagus nerve stimulator" — in Shafer's chest June 23 in New Orleans. It was activated June 24. Copyright © 2004 Yahoo! Inc.

Keyword: Miscellaneous
Link ID: 5738 - Posted: 06.24.2010

LAURA NELSON Jon-Paul Bingham fumbles around for a condom. Big Bertha is waiting. There’s an awkward pause. “It has to be the non-lubricated kind,” he says. Bingham rips open the packet and slips the prophylactic over a small plastic test tube. Big Bertha is one of Bingham’s nine tropical marine cone snails. These colourful creatures are some of the most venomous beasts on the planet. But the powerful poisons they produce can, in tiny doses, help to reveal how nerve cells function — and potentially help to treat conditions from chronic pain to epilepsy. Currently, most neuroscientists obtain their cone snail toxins from dead animals taken from the wild. But Bingham, a biochemist at Clarkson University in upstate New York, believes that the future lies with cone snail farming. Not only might it help conserve wild populations, he says, but it can also yield a wider range of useful toxins. ‘Milking’ the live snails is a hazardous business. One false move and Bingham could be dead in half an hour. Using forceps, he dangles a dead goldfish, the same length as Big Bertha, in front of her. Behind the bait, the condom is stretched over the mouth of the plastic tube. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Neurotoxins
Link ID: 5737 - Posted: 06.24.2010

Bees are not as busy as they are made out to be. In fact the insects are lazy, workshy and prone to sleeping on the job, according to new research. Bees sleep for 80 per cent of the night and like to spend long periods "resting their wings", an award-winning German zoologist has found. Prof Randolf Menzel, from the Free University in Berlin, said that the popular image of bees as the ultimate hard workers was inaccurate. "Bees are not particularly hard working. Instead they sleep a lot and are actually quite lazy," he said. "They spend up to 80 per cent of the night sleeping rather than working in the hive - and during the day they often sit around in the hive resting their wings and doing not much else." Although we see bees buzzing around tirelessly in spring and summer, pollinating flowers and producing honey-filled hives, the common belief in a bee's busy nature is based on a misconception, he said. © Copyright of Telegraph Group Limited 2004.

Keyword: Sleep
Link ID: 5736 - Posted: 06.24.2010

It sounds like the beginning of a joke: "How do bacteria know what time it is?" The surprising answer, reported today in Nature, is that some of these single-celled entities actually have internal clocks. In a living organism, changes in gene expression, physiology and behavior that follow the cycle of day and night are called circadian rhythms. This oscillation is well known to occur in various mammals, insects, plants and fungi. But in recent years researchers have discovered that some single-celled organisms, too, display circadian rhythms. Irina Mihalcescu of the University Joseph Fourier in Saint Martin d'Heres, France, and her colleagues studied cyanobacteria, or blue-green algae, that had been engineered to light up when a particular regulatory gene turned on. By observing the pattern of illumination under a microscope, the scientists could measure the internal clockwork of individual bacteria. Previous research had found that these photosynthetic bacteria keep a daily schedule even without stimuli from the outside world. Under such constant conditions, Mihalcescu and her co-workers found that the bacteria maintained a specific rhythm even following cell division--that is, the clock-setting was passed on to subsequent generations. To determine whether intercellular interactions influence this synchronicity, the team grew two cell colonies shifted in time by three hours--like New Yorkers and Californians. When the scientists combined the bacteria, individuals resisted changing their clocks even when butting up against those from a different time zone. © 1996-2004 Scientific American, Inc. All rights reserved.

Keyword: Biological Rhythms
Link ID: 5735 - Posted: 06.24.2010

CHAPEL HILL -- Scientists at the University of North Carolina at Chapel Hill have discovered key steps involved in regulating nerve growth and regeneration that may have implications for spinal cord research. The new research, published in the June 24 issue of the journal Neuron, for the first time describes how nerve growth factor (NGF) stimulates a sequence of proteins – a molecular pathway – that promotes nerve growth. "It is the first study to show the link between NGF and the building blocks that form the axon," said Dr. William Snider, professor of neurology and cell and molecular physiology at UNC's School of Medicine and director of the UNC Neuroscience Center. Axons are long tendrils, or processes, that extend from nerve cells to form connections with other nerve cells, muscles and the skin. Injury to the peripheral nervous system – that portion of the nervous system outside the brain and spinal cord – typically results in spontaneous regeneration and repair. However, this is not the case with the spinal cord, where disruption of connections from injury leads to paralysis

Keyword: Regeneration
Link ID: 5734 - Posted: 06.24.2010

By Rossella Lorenzi, Discovery News — Males do not listen, at least if they are Manx shearwater sea birds, new research has shown. Puffinus puffinus, best known as Manx shearwaters for their habit of gliding on stiff wings along the troughs of waves, marry for life and share the incubation of a single egg. The chick is then raised by both parents who feed it with regurgitated food. Scientists at Leeds and Cardiff universities put microphones into the burrows of nesting shearwaters and discovered that males regularly provide more food to their offspring than the females. “ Males return to the nest at least once every four days, bringing back food with predictable regularity, regardless of the chick's cries. ” The reason is not that they are better parents, said Keith Hamer of Leeds University's biology department — they just don't listen to the begging calls of their chicks. Copyright © 2004 Discovery Communications Inc.

Keyword: Animal Communication; Sexual Behavior
Link ID: 5733 - Posted: 06.24.2010