A type of drug used to treat schizophrenia can protect brain cells from a virus that causes a fatal nervous system disorder, say experts. The disorder is called progressive multifocal leukoencephalopathy or PML. It affects people with weakened immune systems, such as people with Aids or organ transplant patients. A US study in Science found the antipsychotic drug clozapine appeared to be most effective at preventing the infection without side-effects. PML is caused by a virus which destroys glial cells that produce the fatty sheath that covers nerve cells. Most people carry the virus. But a healthy immune system suppresses it, and it only causes PML in people with weakened immune systems. The symptoms of PML include dementia, vision loss, movement and speech impairment, paralysis and coma. The condition is always fatal. The scientists found the virus attaches itself to a receptor on the surface of glial cells. That receptor opens and allows the virus to get inside cells. It normally binds with serotonin, a brain chemical that plays an important role in depression and anxiety, leading the scientists to investigate if medications which act as serotonin-receptor blockers could be effective. The team at Brown University and Case Western Reserve University focussed on a particular protein, called clathrin within the cells, which plays a role in bringing substances into the cell. They then tested drugs to see which might be effective in blocking the action of this protein. Chlorprozamine, a drug used to control psychotic symptoms such as hallucinations and delusions, was found to work. But it can cause serious side effects, such as lowered blood pressure, stiffness and tremors. This led the team to test seven similar drugs. They found that three others, most notably the antipsychotic clozapine, also prevented infection in human glial cells without the side effects. (C)BBC

Keyword: Schizophrenia; Glia
Link ID: 6457 - Posted: 11.21.2004

By RALPH BLUMENTHAL - It's a burning issue for some hot-pepper lovers: Whatever possessed Kevin M. Crosby to create the mild habanero? For Dr. Crosby, a plant geneticist at the Texas A&M Agricultural Experiment Station here near the Mexican border, the answer is simple: "I'm not going to take away the regular habanero. You can still grow and eat that, if you want to kill yourself." But for those who prize the fieriest domesticated Capsicum for its taste and health-boosting qualities, Dr. Crosby and the research station in the Rio Grande Valley have developed and patented the TAM Mild Habanero, with less than half the bite of the familiar jalapeño (which A&M scientists also previously produced in a milder version). With worldwide pepper consumption on the rise, according to industry experts, the new variety - a heart-shaped nugget bred in benign golden yellow to distinguish it from the alarming orange original, the common Yucatan habanero - is beginning to reach store shelves, to the delight of processors and the research station, which stands to earn unspecified royalties if the new pepper catches on. "I love it," said Josh Ruiz, a local farmer whose pickers this week filled some 200 boxes of the peppers to be sold to grocers for about $35 a box. "It yields good and I'm able to eat it." As for the Yucatan habanero, he said, "My stomach just can't take it." Copyright 2004 The New York Times Company

Keyword: Pain & Touch
Link ID: 6456 - Posted: 11.21.2004

Functional MRI shows genetic effects on the human brain more clearly By Jack Lucentini Deciphering genetic relationships in cognitive function takes serious effort. Michael Posner at the University of Oregon in Eugene and colleagues found that a diminished ability to focus could be linked to two specific mutations.1 The study involved a battery of genetic and cognitive tests given to more than 200 people. A year later, in 2003, Posner added clarity to the finding using functional magnetic resonance imaging (fMRI). The researchers linked the mutations to differing activity in the anterior cingulate cortex.2 This study required only 16 subjects. Though some might question the use (and abuse) of fMRI data, others say that neuroimaging is an unexpectedly powerful way to study genetic effects on brain function. Effects show up more obviously in scans than in behavior. "I think everybody has been surprised by the power of imaging strategies," says Daniel Weinberger, a senior investigator at the National Institutes of Health. Researchers say future studies of this type should clarify gene-gene interactions at one of their most befuddling crossroads, the human brain. Imaging technology is largely believed to demonstrate active areas of the brain, something that can't be recorded using cognitive tests. "The closer you get to how genes work, the stronger the effects of the gene are," says Michael Egan, also at the NIH. Egan and colleagues found that a common variant in the gene coding catechol-O-methyltransferase (COMT) boosts schizophrenia risk by 50%.3 They also found that the variant has a more common effect-- it slightly worsens working memory--and an even more frequent one evident only on scans: It reduces efficiency of prefrontal cortex function during working memory tasks. Genetic effects are much more blatant in the brain than in behavior, says Weinberger. "[Genes] code for simple molecules and cells. There are a lot of steps between a gene and the behavior." © 2004, The Scientist LLC,

Keyword: ADHD; Genes & Behavior
Link ID: 6455 - Posted: 06.24.2010

By Laura Spinney Epilepsy often develops after the brain is damaged, and patients commonly must take anticonvulsant drugs for a lifetime despite unpleasant side effects. Such drugs target the seizures but not the underlying cause. Now, new theories promise to untangle the mechanisms of epileptogenesis and presage the possibility of a new generation of drugs that treat the initial brain damage and prevent epilepsy from developing. In roughly half of all patients with epilepsy, the condition develops later in life after the patient sustains a brain injury such as trauma or meningitis. The latency of onset can range from a few weeks to a decade after brain damage occurs. Researchers have been scrambling to uncover what happens during that delay. SIMPLE BALANCE A generally held theory suggests that something upsets the balance of excitatory and inhibitory signals in the brain, leading to overall hyperexcitability. This theory rests on observations that inhibitory cells become less active while excitatory pathways multiply, implying "a simple balance of inhibition and excitation," according to John Duncan of the Institute of Neurology in London. He says that this theory is probably wrong, or at least incomplete. "The reality is clearly more complicated, as neurons form intricate networks and interconnections." © 2004, The Scientist LLC,

Keyword: Epilepsy
Link ID: 6454 - Posted: 06.24.2010

Parents dismayed as Supreme Court refuses to enshrine kids' treatment in constitution The B.C. government is not obligated to provide expensive early-intervention therapy for autistic children, the Supreme Court of Canada ruled Friday in a key decision that has much wider ramifications for all provincial governments. The court's unanimous decision refusing to elevate health funding to a constitutional right overturned two B.C. court rulings that found the province violated the Charter of Rights equality guarantees for disabled people. B.C. Attorney General Geoff Plant said the ruling means governments and not the courts are clearly responsible for social policy and health-care decisions. The earlier B.C. court decisions said the province had discriminated against four autistic children named in a lawsuit by not providing them with Lovaas treatment, an early intensive behavioural therapy which can cost up to $60,000 per child annually. Autism is a neuro-behavioural syndrome that impairs communication and social interaction, often resulting in repetitive behaviour. Lovaas therapy, pioneered by U.S. psychologist Ivar Lovaas, includes 20 to 40 hours of therapy per week and has produced dramatic results in some cases. Some B.C. parents have gone through extremely difficult financial times to fund the program themselves. Copyright © 2004 CanWest Interactive Inc.

Keyword: Autism
Link ID: 6453 - Posted: 06.24.2010

A charity set up after the death of a Bradford schoolgirl is highlighting the dangers of substance abuse. The Chantelle Bleau Memorial Fund hosted a national conference in Bradford on Friday to alert people to the dangers of solvents. Chantelle, 16, a former classmate of pop star Gareth Gates, died in December 1996 after inhaling gas from a lighter refill. The pop star said her death was an appalling waste of a young life. Gareth Gates said: "Chantelle was bright, bubbly and full of fun and her death came as an enormous shock to all of her school friends. "That is why I have always been an enthusiastic supporter of the charity set up in her memory to highlight the enormous dangers of sniffing and inhaling toxic substances such as butane gas. "I am full of admiration for Chantelle's family setting up this charity and to all the staff and volunteers who give so much dedicated time to making people aware how serious this problem is." A charity spokesman said on average five youngsters die each month of solvent abuse. Of those, one in four is a first time user. The conference was jointly hosted with Solve It, a charity which advises parents on solvent issues. (C)BBC

Keyword: Drug Abuse
Link ID: 6452 - Posted: 11.20.2004

Nancy Pinsker ticks off the names of five blue items, noting last the sky. She's better at this than she was five years ago when a stroke put a stranglehold on her vocal muscles, altering her speech. Since then, she's been chipping away at reclaiming the capacity for normal conversation. "I feel if I don't come here and take lessons, I'll lose my voice," says the retired bookkeeper, now in her seventies. "Even now, it's not perfect." For people like Pinsker who find it hard to engage in conversation, a host of new technology awaits. "There's just been an explosion," says Stephen Cavallo, a speech-language pathologist and associate professor at Lehman College, where Pinsker frequents the Speech and Hearing Center. Now NASA researchers are taking a leap in the direction of deciphering speech. Neuroengineer Chuck Jorgensen told Discover Magazine that he's bypassing the physical body's normal requirements by delivering words via machine using subvocal speech. "When you're reading material…sometimes you find that your tongue or your lips are quietly moving but you're not making an audible sound," he explains. "And it's doing that because there's this electronic signal that's being sent to produce that speech but you're intercepting it so it doesn't really say it out loud. That's subvocal speech." © ScienCentral, 2000- 2004.

Keyword: Language
Link ID: 6451 - Posted: 06.24.2010

An electronic "artificial eye", developed for people with impaired vision, has been shown to reliably identify pedestrian crossings, determine when it is safe to walk across and even measure the width of a road. The system, created by Tadayoshi Shioyama and Mohammad Uddin, at the Kyoto Institute of Technology in Japan, consists of a single miniature camera that can be clipped onto a pair of glasses and a small wearable computer that analyses video images. The artificial eye can identify Japanese pedestrian crossings by recognising the white stripes painted across the centre of a road. It can also tell when the signal is flashing to indicate that it is safe to cross. In testing, it successfully identified a crossing 196 times out of 198 and never “found” a crossing where there was not one. Furthermore, the system can measure the distance of a crossing to within the accuracy of a single step. The length of the crossing - the width of the road - is calculated using projective geometry. Some, but not all, pedestrian crossing systems beep to let blind pedestrians know when to cross. This system "relays information using a voice speech system and gives vocal commands and information through a small speaker placed near the ear," says Shioyama. © Copyright Reed Business Information Ltd.

Keyword: Vision; Robotics
Link ID: 6450 - Posted: 06.24.2010

New Haven, Conn.--Imaging studies of the brain when it is under the influence of alcohol reveal that different areas of the brain are impaired under high and low levels of alcohol, according to a Yale study published in Neuropsychopharmacology. Godfrey Pearlson and Vince Calhoun, researchers in the Department of Psychiatry at Yale School of Medicine, used a statistical method to sort areas of the brain affected when persons were administered a placebo or two different doses of alcohol. The seven men and two women then "drove" using a simulated driving skill game. "What we found is that when people were really intoxicated, they drove like they were really intoxicated and in a real vehicle," Pearlson said. "They speeded up, especially on corners, where most people slow down, and crashed more often into other vehicles." When mildly intoxicated, but below the legal alcohol limit, he said, the drivers seemed aware of the fact that they were impaired and corrected for the deficit. The researchers also found that alcohol had a profound effect on some, but not all, brain circuits activated in sober driving. The areas most profoundly affected by alcohol were the orbital frontal and anterior cingulate areas, which help control motor functions. The medial frontal regions of the brain involved in making decisions, and working memory, were not affected until the person was beyond the legal limit of intoxication. A function of working memory might be to find one's way home, the researchers said.

Keyword: Drug Abuse
Link ID: 6449 - Posted: 11.20.2004

Ben Harder An experimental diet drug looks like a long-distance success. New data indicate that obese adults who lose weight during a year of taking rimonabant and dieting keep the weight off during the following year, if they continue the regimen. The drug, which Paris-based manufacturer Sanofi-Aventis calls Acomplia, blocks cells' receptors for chemicals called cannabinoids, which include substances in marijuana. Some cravings for food and addictive substances depend on those receptors. Yearlong trials of rimonabant had suggested that the drug aids initial weight loss. But the real test of an obesity treatment is whether weight shed in one year stays away the next. So, endocrinologist F. Xavier Pi-Sunyer of Columbia University and his colleagues at 64 U.S. and 8 Canadian institutions enlisted more than 3,000 obese volunteers, mostly women, who agreed to take a daily pill while attempting to diet for 2 years. Throughout the study, investigators recorded the volunteers' weight, blood concentrations of cholesterols, and other indicators of metabolic health. During the first year, two-fifths of the volunteers took 20 milligrams per day of rimonabant, a similar number took 5 mg/day, and the rest took a placebo pill. Copyright ©2004 Science Service.

Keyword: Obesity
Link ID: 6448 - Posted: 06.24.2010

By DONALD G. McNEIL Jr. A possible new case of mad cow disease has been found in the United States, the Agriculture Department said yesterday. The agency said the brain of a cow tested positive three times on a rapid test for the presence of prions, the misfolded proteins that cause the disease. The department considers the rapid test inconclusive. The results await confirmation by more complex tests, and experts expect those to take four to seven days at the National Veterinary Services Laboratory in Ames, Iowa. A food safety expert who frequently criticizes the testing program said the results made it almost certain that the cow was infected. The expert, Dr. Michael K. Hansen, a senior research associate at Consumers Union, put the chances of an error at one in 100,000. Infected or not, the animal "did not enter the food or feed chain," said Dr. Andrea Morgan, associate deputy administrator of the Animal and Plant Health Inspection Service, part of the Agriculture Department. Copyright 2004 The New York Times Company

Keyword: Prions
Link ID: 6447 - Posted: 11.19.2004

By Simon Cox and Richard Vadon The tactics of a small hardcore of animal rights activists have brought them in confrontation with major corporations, scientific establishments and the government. Some of their strategies have appalled many people, especially those who have been targeted. Whether people support them or not, it cannot be denied that their tactics have had an impact. So what have been the key elements of their approach? The campaign waged against Huntingdon Life Sciences, Europe's largest vivisection laboratory, has shown the increasingly sophisticated tactics of the animal rights movement. The Stop Huntingdon Animal Cruelty (Shac) campaign has focused on the suppliers. So far this year 80 companies have severed ties with Huntingdon because of pressure from animal rights campaigners and fear of bad publicity. Greg Avery of the Shac campaign has found that many of the biggest companies can be persuaded very quickly and not because they care about animals. (C)BBC

Keyword: Animal Rights
Link ID: 6446 - Posted: 11.19.2004

A menacing body posture can be as threatening as a frightening facial expression, according to new research. In the past, scientists have said that human emotions are communicated mainly by facial expressions. But a new study suggests that body posture may be as important as the face in communicating emotions such as fear. The discovery suggests that the immediate response to other people's fear may be more automatic than previously thought. The study shows that images of fear affect the emotional part of the brain. Since the link between the emotional brain and action is stronger than the link between the visual brain and action, viewing fearful body expressions may automatically prepare the observer to respond to fear. "When we talk about how humans communicate, we always talk about things like language," said Beatrice de Gelder, the neuroscientist who led the study. "But just like in the animal world, we also communicate through our bodies without our conscious minds being much aware of it." De Gelder is a professor at both Harvard Medical School in Massachusetts, and Tilburg University in the Netherlands. The study is published in the Proceedings of the National Academy of Sciences this week. © 2004 National Geographic Society.

Keyword: Emotions; Language
Link ID: 6445 - Posted: 06.24.2010

Holds hope for sufferers of macular degeneration Boston, MA – For the first time researchers have shown that transplanted stem cells can preserve and improve vision in eyes damaged by retinal disease. In the cover article in the November 2004 Investigative Ophthalmology and Visual Science, scientists from Harvard's Schepens Eye Research Institute describe results of a mouse study in which transplanted stem cells develop into retinal cells, prevent the death of "at risk" retina cells in the recipient mice and improve the vision of treated mice. "These findings hold great promise for potential treatments for people suffering from macular degeneration, diabetic retinopathy and other retinal diseases," says Michael Young, PhD, an assistant scientist at Schepens Eye Research Institute and the lead author of the study. The retina is a tissue-thin membrane at the back of the eye responsible for sending light and images from the outside world through the optic nerve to the brain, which interprets them. The retina contains light sensitive cells, known as rods, which make it possible for us to see in black and white and in low light, and cones, which are responsible for color and high-acuity vision. In diseases such as macular degeneration, it is these cells that are being destroyed.

Keyword: Vision; Stem Cells
Link ID: 6444 - Posted: 06.24.2010

Using ultrasound in combination with the drug t-PA can improve response to an ischemic stroke, according to a study involving 126 patients. This first-of-its-kind human trial compared the safety and efficacy of ultrasound and t-PA versus use of t-PA alone. The trial was funded in part by the National Institute of Neurological Disorders and Stroke (NINDS), a component of the National Institutes of Health (NIH). The finding appears in the November 18, 2004, issue of the New England Journal of Medicine. Since 1996, the clot-busting drug t-PA (tissue plasminogen activator) has been the only FDA-approved therapy for acute ischemic stroke. Previous studies have shown that t-PA, when administered within 3 hours of onset of ischemic stroke, can greatly improve a patient's chance for a full recovery. t-PA cannot be used to treat the less common hemorrhagic stroke. Researchers wanted to test the effectiveness of using transcranial Doppler ultrasound (TCD) in combination with t-PA, and to ensure that ultrasound did not cause bleeding into the brain. Utrasound is a safe, non-invasive, FDA-approved diagnostic test that uses sound waves to measure blood flow velocity in large arteries. An international team led by Andrei Alexandrov, M.D., associate professor of neurology at the University of Texas-Houston School of Medicine, examined 126 patients who suffered an ischemic stroke. All patients received intravenous t-PA within 3 hours of stroke onset. The 63 patients in the control group received t-PA alone, while the other 63 patients received t-PA in combination with continuous TCD monitoring that started shortly before the patients received the drug. A small device attached to a head frame was used to deliver the ultrasound.

Keyword: Stroke
Link ID: 6443 - Posted: 11.19.2004

Maltreated children who are genetically pre-disposed to depression can be spared lifelong emotional problems if the necessary social supports are made available to them, according to a Yale study published this week in the Proceedings of the National Academy of Sciences. There are nearly one million substantiated reports of child maltreatment each year, according to the U.S. Department of Health and Human Services. Joan Kaufman, associate professor of psychiatry at Yale School of Medicine and author of the study, said many, but not all abused children develop chronic difficulties, particularly depression. Previous studies have shown that a malfunction in the serotonin transporter gene is associated with the development of depression, but only in adults with histories of childhood maltreatment or recent stressful life events. After the release of serotonin from a cell into the synapse, this transporter takes the extra serotonin back into the cell so it is not degraded. In genetic pre-disposition to depression, fewer and less efficient transporter molecules are made. Kaufman said the altered serotonin transporter gene was found in both maltreated children and those who were not maltreated, but was only associated with depression in children who had no positive supports. Social support was defined as someone a child could talk to about personal things, count on to buy the things they need, share good news with, get together with to have fun, and go to if they need advice.

Keyword: Depression; Development of the Brain
Link ID: 6442 - Posted: 11.19.2004

Michael Hopkin Fossil hunters in Spain have unearthed what seems to be the most recent common ancestor of gorillas, chimpanzees, orang utans and humans. The ape lived almost 13 million years ago, about the time that our different lineages are thought to have diverged. The species has been christened Pierolapithecus catalaunicus, in reference to the Catalan village of Els Hostalets de Pierola, where the fossil was found. The specimen consists of 83 bones from an adult male, including parts of the skull, teeth, ribs and fingers. The creature would have weighed about 55 kilograms, making it about the size of a female chimpanzee, says Salvador Moyá-Solá of the Miquel Crusafont Institute of Palaeontology in Barcelona, whose team reports the discovery in this week's Science1. But it would have looked more like a primitive gorilla, he adds. The scarcity of the fossil record makes it difficult to say whether P. catalaunicus is actually the most recent common ancestor of all great apes living today, Moyá-Solá says. But it is likely to resemble it closely: analyses of the rates at which differences arise between our DNA and that of other apes show that our family must have begun diverging at about the time when P. catalaunicus was alive. ©2004 Nature Publishing Group

Keyword: Evolution
Link ID: 6441 - Posted: 06.24.2010

Researchers have shown in animal studies how receptors on nerve cells can become altered to produce chronic pain triggered by inflammation. They say that their findings could aid in developing new drugs to treat such chronic pain, which is distinct from the relatively short-lived pain from injury, which fades as the injury heals. In their experiments, Bettina Hartmann and her colleagues studied receptors called AMPA receptors, which are triggered by the neurotransmitter glutamate. Such receptors are protein switches that nestle in the membranes of nerve cells and, when triggered, induce either short-term or long-term changes in the nerve cells. A short-term change might be the triggering of a single nerve impulse; but AMPA receptors have been implicated in long-lasting changes such as adjusting the strength of nerve cell connections, or synapses, in learning and memory. AMPA receptors regulate nerve cell response by opening to enhance calcium flow into the cell, heightening the cells' sensitivity to producing nerve impulses when triggered. According to Hartmann and her colleagues, studies of spinal cord tissue showed that AMPA receptors are found in spinal cord regions known to be responsible for pain sensing, or nociception. However, they said, there had been no studies that explored what role the receptors played in whole animals.

Keyword: Pain & Touch
Link ID: 6440 - Posted: 11.18.2004

ITHACA, N.Y. -- A group of chemicals in apples could protect the brain from the type of damage that triggers such neurodegenerative diseases as Alzheimer's and Parkinsonism, according to two new studies from Cornell University food scientists. The studies show that the chemical quercetin, a so-called phytonutrient, appears to be largely responsible for protecting rat brain cells when assaulted by oxidative stress in laboratory tests. Phytonutrients, such as phenolic acids and flavanoids, protect the apple against bacteria, viruses and fungi and provide the fruit's anti-oxidant and anti-cancer benefits. Quercetin is a major flavanoid in apples. Antioxidants help prevent cancer by mopping up cell-damaging free radicals and inhibiting the production of reactive substances that could damage normal cells. "The studies show that additional apple consumption not only may help reduce the risk of cancer, as previous studies have shown, but also that an apple a day may supply major bioactive compounds, which may play an important role in reducing the risk of neurodegenerative disorders," says Chang Y. "Cy" Lee, Cornell professor of food science at the university's New York State Agricultural Experiment Station in Geneva, N.Y.

Keyword: Alzheimers; Parkinsons
Link ID: 6439 - Posted: 11.18.2004

The UK has seen the fastest rise in the prescribing of antidepressants and other mind-altering drugs to children, a study of nine countries shows. University of London researchers compared prescribing rates between 2000 and 2002 in countries in Europe, South America and North America. During that period, the UK saw a 68% rise in children being prescribed drugs to stimulate or calm the brain. The research is published in Archives of Disease in Childhood. Some common antidepressants were withdrawn from UK paediatric use last year, but the researchers say doctors are likely to move to others. The team, from the School of Pharmacy at the University of London looked at prescribing of antidepressants, stimulants, antipsychotics, tranquilisers and medications to treat anxiety. They examined prescription data for children up to 17 in the UK, France, Germany, Spain, Argentina, Brazil, Mexico, Canada and the US. The information came from an international database (IMS MIDAS), which draws on data from a representative sample of medical practitioners in each country. It was found children are generally being prescribed more antidepressants and other drugs designed to calm or stimulate the brain. The highest increase of 68% was recorded in the UK. Many of the prescriptions were for medications used in the treatment of Attention Deficit Hyperactive Disorder. Significant rises in the number of prescriptions for these drugs were evident in all countries, except Canada and Germany where the increase in prescriptions over the period was just 13%. (C)BBC

Keyword: Depression; Development of the Brain
Link ID: 6438 - Posted: 11.18.2004