Damaged optic nerves - which run from the eye to the brain - have been regrown for the first time by scientists working with mice. The researchers believe the technique might one day restore sight to people whose optic nerves have been damaged by injury or glaucoma. It could even help regenerate other nerves in the body, they say. A team led by Dong Feng Chen, at the Schepens Eye Research Institute in Boston, US, combined two genetic modifications to regrow the optic nerve after it was damaged. First they turned on a gene called BCL-2, which promotes growth and regeneration of the optic nerve in young mice. This gene is normally turned off shortly before birth. They then bred those animals with other mice carrying genetic mutations that reduce scar tissue in injured nerves. The researchers crushed the optic nerves shortly after birth, and found that in young mice - less than 14 days old - between 40% and 70% of the injured optic nerve fibres regrew to reach their target destinations in the brain. No regrowth was seen in injured mice without the genetic modifications. That suggests the mice may have regained some vision, Chen told New Scientist, although the study cannot prove it did. © Copyright Reed Business Information Ltd.

Keyword: Regeneration; Glia
Link ID: 6929 - Posted: 06.24.2010

Nathan Seppa There's no effective emergency treatment for a cerebral hemorrhage. Roughly 60 percent of people who experience this so-called bleeding stroke die within a year. A new international study, however, indicates that a drug that speeds blood clotting can reduce death and disability after a bleeding stroke, provided that the person is treated promptly. The drug limits the amount of brain tissue damaged by blood leakage, a predictor of how damaging the stroke will be. A cerebral hemorrhage kills neurons and other brain cells at the site of the bleeding and threatens cells on the hemorrhage's periphery. If a doctor could limit the bleeding, a patient would have a better chance of recovery, says study coauthor Stephan A. Mayer, a neurologist at the Columbia University College of Physicians and Surgeons in New York. Mayer and a team of physicians in North America, Europe, Asia, and Australia treated 303 bleeding-stroke patients with an intravenous drug called recombinant activated factor VII (rFVIIa), which certain hemophilia patients receive under the brand name NovoSeven. The researchers gave a placebo infusion to 96 other patients with bleeding strokes. Upon admission to a hospital and 24 hours later, each participant underwent computed tomography brain scans to detect bleeding. Copyright ©2005 Science Service.

Keyword: Stroke
Link ID: 6928 - Posted: 06.24.2010

A rigorous study in Italy has confirmed claims that professional soccer players have a higher than normal risk of developing a type of motor neuron disease, also known as amyotrophic lateral sclerosis. The reason remains a mystery. ALS involves the death of motor neurons, the nerve cells responsible for voluntary movement, and eventually leads to paralysis and death. Adriano Chiň's team at the University of Turin surveyed the medical records of 7000 professional footballers who played in Italy's first or second division between 1970 and 2001. Based on the normal incidence of the disease and the players' ages, the researchers calculated that there should have been 0.8 cases of ALS in this group. Instead, there were five. The study was prompted by what the Italian press dubbed "the motor neuron mystery" - the discovery a few years ago of 33 cases of ALS during an investigation of illicit drug use among 24,000 pro and semi-pro players in Italy. Dubious about the methodology of that initial investigation, Chiň's group applied stricter diagnostic criteria to their data, such as only including players born in Italy. "I think the researchers have been conservative," says Ammar Al-Chalabi of the Institute of Psychiatry in London, who has written a commentary on the study in Brain. © Copyright Reed Business Information Ltd.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 6927 - Posted: 06.24.2010

The active ingredient in marijuana may stall decline from Alzheimer's disease, research suggests. Scientists showed a synthetic version of the compound may reduce inflammation associated with Alzheimer's and thus help to prevent mental decline. They hope the cannabinoid may be used to developed new drug therapies. The research, by Madrid's Complutense University and the Cajal Institute, is published in the Journal of Neuroscience. The scientists first compared the brain tissue of patients who died from Alzheimer's disease with that of healthy people who had died at a similar age. They looked closely at brain cell receptors to which cannabinoids bind, allowing their effects to be felt. They also studied structures called microglia, which activate the brain's immune response. Microglia collect near the plaque deposits associated with Alzheimer's disease and, when active, cause inflammation. The researchers found a dramatically reduced functioning of cannabinoid receptors in diseased brain tissue. This was an indication that patients had lost the capacity to experience cannabinoids' protective effects. The next step was to test the effect of cannabinoids on rats injected with the amyloid protein that forms Alzheimer's plaques. Those animals who were also given a dose of a cannabinoid performed much better in tests of their mental functioning. The researchers found that the presence of amyloid protein in the rats' brains activated immune cells. However, rats that also received the cannabinoid showed no sign of microglia activation. Using cell cultures, the researchers confirmed that cannabinoids counteracted the activation of microglia and thus reduced inflammation. (C)BBC

Keyword: Alzheimers; Drug Abuse
Link ID: 6926 - Posted: 02.23.2005

By Paul Rincon Pets should be matched with their owners on the basis of similar personalities Dogs show huge differences in personality, according to a US scientist who has developed a test to assess canine character. Dr Sam Gosling, of the University of Texas, rates the dogs on four key traits with positive and negative extremes. He adds that his work suggests pets should be matched with owners who have similar personalities. The work was presented at a major science conference in Washington DC. "We used approaches used to assess human personality and applied them to dogs," said Dr Gosling. "You do find personality differences between breeds. Indeed, many have been bred on that basis. But you also find enormous [personality] differences within the breeds themselves." Dr Gosling first asked pet owners to rate their pet on the four personality traits and then asked strangers to rate the animals on the same characteristics. The four dog personality factors were energy levels, affection-aggression, anxiety-calmness and intelligence-stupidity. Anxiety-calmness was assessed by studying a dog's reaction as its owner walked away with another dog. The ability to retrieve a biscuit from beneath a cup was used as a measure of intelligence. These traits were adapted from the five-factor model; used to assess human personality. And the University of Texas psychologist is a firm believer that pets should be matched with their owners on the basis of similar personalities. "If you can make a breed-based judgment that's fine. But you can also do behavioural tests. And one of the places that are very interested in this are dog homes. (C)BBC

Keyword: Emotions
Link ID: 6925 - Posted: 02.23.2005

By Paul Rincon Crows and jays are the brain boxes of the bird world, according to a Canadian scientist who has invented a method of measuring avian IQ. The IQ scale is based on the number of novel feeding behaviours shown by birds in the wild. The test's creator Dr Louis Lefebvre was surprised that parrots were not high in the pecking order - despite their relatively large brains. The research was presented at a major science conference in Washington DC. The avian intelligence index is based on 2,000 reports of feeding "innovations" observed in the wild and published in ornithology journals over a period of 75 years. "We gathered as many examples as we could from the short notes of ornithology journals about the feeding behaviours that people had never seen or were unusual," said Dr Lefebvre, of McGill University in Montreal, Canada. "From that we established different numbers for different birds. There are differences. There are some kinds of birds that score higher than others. "The crows, the jays, that kind of bird - the corvidae - are the tops; then the falcons are second, the hawks the herons and the woodpecker rank quite high." Dr Lefebvre said that many of the novel feeding behaviours he included in the work were mundane, but every once in a while, birds could be spectacularly inventive about obtaining their food. During the war of liberation in Rhodesia, now Zimbabwe, a soldier and avid bird watcher observed vultures sitting on barbwire fences next to mine fields waiting for gazelles and other herbivores to wander in and get blown to smithereens. "It gave them a meal that was already ground up," said Dr Lefebvre. "The observer mentioned that once in a while a vulture was caught at its own game and got blown up on a mine." (C)BBC

Keyword: Intelligence; Evolution
Link ID: 6924 - Posted: 02.23.2005

Scientists have homed in on a gene that might be involved in dyslexia, a condition that causes difficulty with reading and spelling. The gene has appeared as a suspect before, and researchers hope that the new findings will help them better understand what happens in the brains of people with this condition, as well as provide insights into the workings of language. Dyslexia afflicts up to 10% of the population, and although those individuals have trouble with reading and spelling, they often have normal or even above-average intelligence. They also use slightly different parts of their brains than the average person does when reading and writing. The condition seems to be at least partly inherited, but it has been a challenge to find any of the genes involved, which are most likely scattered across several chromosomes. Now, researchers believe that they are one step closer to fingering a possible culprit. Natalie Cope and Julie Williams of Cardiff University in the United Kingdom and their colleagues studied 223 people with dyslexia, as well as their families and 273 controls. The team reports in the current issue of the American Journal of Human Genetics that those with dyslexia had a strong tendency to carry alterations in KIAA0319, a gene on chromosome 6p. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Dyslexia; Genes & Behavior
Link ID: 6923 - Posted: 06.24.2010

WASHINGTON, DC -- A substance similar to a drug used in the treatment of Parkinson's disease blocks the stimulating effects of cocaine and could potentially be used to develop drug therapy for cocaine abuse, new research shows. In an article published in the February 23, 2005, issue of The Journal of Neuroscience, Jonathan Katz and his colleagues at the National Institute on Drug Abuse (NIDA) report the results of experiments showing that mice treated with a substance similar to the drug benztropine did not show any of the typical hyperactive behavior when later injected with cocaine. This effect wore off after a day. Cocaine produces intense feelings of euphoria by increasing the amount of dopamine that is sent from one neuron to another within the brain reward system. Dopamine signals pleasure and reward by binding to receptors on the receiving neurons, after which it is reabsorbed for later use by a protein that transports it back into the sending neuron. But cocaine blocks the mechanism that transports dopamine, causing it to build up and send an unceasing message of pleasure – the cocaine high. Researchers have long searched for "a molecule that would block cocaine's effects on the transporter without inhibiting the transporter by itself," notes Eric Nestler, chair of psychiatry at the University of Texas Southwestern Medical Center in Dallas.

Keyword: Drug Abuse
Link ID: 6922 - Posted: 06.24.2010

Alzheimer's is a complex disease with a multitude of contributing factors. Not surprisingly, researchers have been laboring for decades to better understand its development and to find a treatment. It would be reasonable to expect that this Gordian knot of a disease would require an impressively high-tech therapy. Yet it turns out that many familiar products, including tea, over-the-counter painkillers, cholesterol drugs, and antidepressants, may have some efficacy in battling Alzheimer's. Study of the activities of such prosaic items is helping illuminate just how this disease develops. At the same time, the knowledge gained suggests how the disease can be fought--information that complements insights gleaned from the high-tech arena. One class of medication that may reduce one's risk of getting Alzheimer's disease is familiar to anyone who takes drugs such as ibuprofen (Advil, for example). Unfortunately, some of these nonsteroidal anti-inflammatory drugs (NSAIDs), which are currently marketed as pain relievers, have recently come under suspicion of causing cardiovascular problems (C&EN, Jan. 3, page 7). The emergence of these possible side effects has brought clinical trials of NSAIDs as a potential Alzheimer's treatment to a halt. Nevertheless, valuable information can still be garnered from studies of the drugs. Copyright © 2005 American Chemical Society

Keyword: Alzheimers
Link ID: 6921 - Posted: 06.24.2010

Richard Dawkins I am writing this on a boat (called the Beagle, as it happens) in the Galápagos archipelago, whose most famous inhabitants are the eponymous (in Spanish) giant tortoises, and whose most famous visitor is that giant of the mind, Charles Darwin. In his account of the voyage of the original Beagle, written long before the central idea of The Origin of Species condensed out of his brain, Darwin wrote of the Galápagos Islands: "Most of the organic productions are aboriginal creations, found nowhere else; there is even a difference between the inhabitants of the different islands; yet all show a marked relationship with those of [South] America, though separated from that continent by an open space of ocean, between 500 and 600 miles in width. The archipelago is a little world within itself ... Considering the small size of the islands, we feel the more astonished at the number of their aboriginal beings, and at their confined range ... we seem to be brought somewhat near to that great fact - that mystery of mysteries - the first appearance of new beings on this earth." True to his pre-Darwinian education, the young Darwin was using "aboriginal creation" for what we would now call endemic species - evolved on the islands and found nowhere else. Nevertheless, Darwin already had more than a faint inkling of that great truth which, in his mighty maturity, he was to tell the world. Writing of the small birds now known as Darwin's finches, he said: "Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends." © Guardian Newspapers Limited 2005

Keyword: Evolution
Link ID: 6920 - Posted: 06.24.2010

Problems with the brain – not just the ears – cause a great deal of the age-related hearing loss in older people. Researchers are finding more and more subtle problems in the way our brain processes information as we age, so much so that an older person whose ears are in fine shape may have trouble hearing because of an aging brain. In addition to earlier findings of a specific type of "timing" problem that limits our hearing as we age, the group is now finding increasing evidence of a "feedback" problem in the brain that diminishes our ability to hear. This week at the annual meeting of the Association for Research in Otolaryngology in New Orleans, researchers are discussing the results so far of the hunt for genes that play a role in the aging brain's plummeting ability to organize the information our ears record. "Traditionally, scientists studying hearing problems started looking at the ear," says Robert D. Frisina, Ph.D., professor of Otolaryngology at the University of Rochester Medical Center and an adjunct professor at Rochester Institute of Technology. "But we are finding patients with normal ears who still have trouble understanding a conversation. There are many people who have good inner ears who just don't hear well. That's because their brains are aging."

Keyword: Hearing
Link ID: 6919 - Posted: 06.24.2010

Physical activity may decrease the risk of developing Parkinson's disease, research suggests. Researchers from the Harvard School of Public Health found men who exercised regularly and vigorously early in their adult life had a lower risk. Parkinson's is a progressive nervous disease occurring generally after age 50. It causes muscular tremors, rigidity, and slowing of movement. Details of the study are published in the journal Neurology. The researchers found the most physically active men cut their risk of developing Parkinson's by 50% compared with those who were the least likely to be active. The effect was even more pronounced when strenuous physical activity was involved - those who regularly worked up a sweat had a 60% lower risk than those who never did. The effect did not seem to hold good for women - although there was a small benefit from exercise, it was not statistically significant. The 14-year study focused on more than 48,000 men and 77,000 women. During that time 387 (252 men and 135 women) were diagnosed with Parkinson's. Participants were asked about activities such as walking, hiking, jogging, swimming and sport, but also about the number of stairs they climbed each day. (C)BBC

Keyword: Parkinsons
Link ID: 6918 - Posted: 02.22.2005

By ANAHAD O'CONNOR Reports that a New York man may be carrying a rare and possibly virulent strain of H.I.V. have focused new attention on the biological relationship between the virus and methamphetamine, a drug that has become increasingly entwined in the spread of sexually transmitted diseases in cities from San Francisco to Miami to New York. Although methamphetamine, often called crystal meth or speed, is most troubling to health officials because of its role in blotting out inhibitions and fueling high-risk sexual behavior, experts say they are also grappling with mounting evidence that the drug by itself may increase a person's susceptibility to infection by crippling immune function and facilitating disease transmission. "There seems to be something about methamphetamine that predisposes people to H.I.V. infection," said Dr. Grant Colfax, co-director of the H.I.V. epidemiology biostatistics and intervention section at the AIDS office of the San Francisco Department of Public Health. "When we look at why methamphetamine is increasingly responsible for the H.I.V. epidemic, I do think we need to look more closely at whether it is somehow suppressing immunity and increasing viral loads." The National Institute on Drug Abuse has increased its funding of research on methamphetamine - including studies looking at how it interacts with H.I.V. - to $37 million in 2004 from $27 million in 2003. Copyright 2005 The New York Times Company

Keyword: Drug Abuse; Sexual Behavior
Link ID: 6917 - Posted: 02.22.2005

By NICHOLAS BAKALAR Among famous inventors, Leo H. Sternbach may not immediately leap to mind. But this May in Akron, Ohio, Dr. Sternbach, who is 96, will be inducted into the National Inventors Hall of Fame. He holds more than 240 patents, but perhaps his most famous invention, in collaboration with colleagues, is a chemical compound called diazepam, better known by its brand name, Valium. One of the earliest benzodiazepines, Valium was approved by the Food and Drug Administration in 1963 as a treatment for anxiety, and it would become not only the country's best-selling drug, but an American cultural icon. Referred to knowingly in Woody Allen movies, enshrined as "Mother's Little Helper" in the Rolling Stones song, condemned as poisonous in best-selling books, Valium reached the height of its popularity in 1978, a year when Americans consumed 2.3 billion of the little yellow pills. But by the 1980's its reputation for creating abuse and withdrawal problems was well known, and the new selective serotonin reuptake inhibitors like Prozac were widely considered better treatments for anxiety and panic disorders. Still, the benzodiazepines - there are now more than a dozen others available besides Valium - never disappeared. They are still widely prescribed and, in the view of many doctors, extremely effective in treating not only anxiety and panic disorder, but bipolar illness, insomnia, catatonia and alcohol and drug withdrawal. Copyright 2005 The New York Times Company

Keyword: Emotions; Stress
Link ID: 6916 - Posted: 02.22.2005

Using a molecular approach to understanding human taste perception, researchers have made a new finding demonstrating that each individual's personal set of taste-receptor alleles, or gene variations, codes for distinct receptor proteins that determine individual differences in bitter-taste perception. These differences in perception are ubiquitous, underscoring the idea that, owing to slight variations in our genes for taste receptors, we all live in our own "taste worlds." Thus, we all perceive everyday foods such as teas, coffees, vegetables, meats, beer, cheeses, wines, and chocolates in our own way, potentially with no two tasters exactly alike. The reasons for these perceptual differences involve myriad genes and environmental influences, as well as the interplay between these two factors. The new finding regarding bitterness perception suggests that the taste-receptor genes and their multiple alleles play a dominant role in determining how we perceive the world of tastes. The longest-recognized and most famous genetically determined taste difference among people is the ability to taste PTC (phenylthiocarbamide) as bitter. PTC taste sensitivity varies tremendously among people; the threshold amount of PTC perceptible by individuals varies over a 1000-fold difference in concentration. These different sensitivities form a bimodal distribution in almost every population examined, and this distribution was interpreted as evidence that simple genetic differences, possibly involving only a single gene, underlie the PTC perceptual phenotype. The result was an 80-year-old search for the gene, which was identified last year.

Keyword: Chemical Senses (Smell & Taste); Genes & Behavior
Link ID: 6915 - Posted: 02.22.2005

A leading US nutritionist today claimed that vegetarian and vegan parents are damaging their children's health by denying them meat. UK experts immediately contested the findings of Professor Lindsay Allen, of the University of California at Davis, and Sir Paul McCartney told the BBC that the claims were "rubbish". Prof Allen conducted a study of impoverished children in Kenya, and found that adding as little as two spoonfuls of meat a day to their starch-based diets dramatically improved muscle development and mental skills. Speaking at the annual meeting of the American Association for the Advancement of Science, in Washington DC, she said: "Animal source foods have some nutrients which are not found anywhere else. "If you're talking about feeding young children and pregnant women and lactating women, I would go as far as to say it is unethical to withhold these foods during that period of life. There's a lot of empirical research that will show the very adverse effects on child development of doing that." Prof Allen was especially critical of parents who imposed a vegan lifestyle on their children, denying them milk, cheese, eggs and butter, as well as meat. "There's absolutely no question that it's unethical for parents to bring up their children as strict vegans," she said. © Guardian Newspapers Limited 2005

Keyword: Animal Rights
Link ID: 6914 - Posted: 06.24.2010

How smart is your parakeet or that crow in the back yard? Ask Dr. Louis Lefebvre, inventor of the world's only comprehensive avian IQ index. His intelligence index is not only separating the featherweights from the big bird brains, it's also providing clues about why some birds make great immigrants, as well as insight into the parallel evolution of primate and bird brains. The smarts pecking order is based not on a single bird-in-cage test, but on 2,000 reports of feeding innovations that have been observed in the wild and published in the world's ornithology journals. "Initially, quite honestly, I didn't think it would work," says Dr. Lefebvre, an animal behaviourist at McGill University in Montreal, Canada, who first reported the bird bell curve system in 1997. "Scientists don't like anecdotal evidence. So if you're wary of one anecdote, why would you expect to find a valid pattern in 2,000? I've been waiting for something to come up that would invalidate the system, but nothing has." The biologist, whose work is supported by Science and Engineering Research Canada (NSERC), will present his latest findings at the 2005 American Association for the Advancement of Science meeting in Washington D.C. on February 21. The IQ index draws its strength from the world's legions of avid bird watchers. Professional and amateur birders alike report unusual sightings to refereed ornithology journals, such as the Wilson Bulletin in the U.S. and British Birds.

Keyword: Intelligence; Evolution
Link ID: 6913 - Posted: 02.22.2005

Don't stop and smell the roses: "blinding" an insect's sense of smell may be the best repellent, according to research by Rockefeller University scientists "Pest insects have a profound negative impact on agriculture and human health," says Rockefeller University's Leslie Vosshall, Ph.D. "They are responsible for global losses of crops and stored agricultural products as well as the spread of many diseases." In the heated battle between people and insect pests, Vosshall and colleagues, in collaboration with the biotech company Sentigen Biosciences, Inc., report in the February 22nd issue of Current Biology that an understanding of insects' sense of smell may finally give humans the upper hand. The researchers studied four very different insect species: a benign insect favored by researchers, the fruit fly, which is attracted to rotting fruit, and three pest insects: the medfly, which is a citrus pest; the corn earworm moth, which damages corn, cotton and tomato crops; and the malaria mosquito, which targets humans. They found that one gene, shown to be responsible for the sense of smell in fruit flies, has the same function in these pest insects, which are separated by over 250 million years evolution "While all these insects have sensitive olfactory systems, they all have very different smell preferences," says Vosshall, head of the Laboratory of Neurogenetics and Behavior. "Yet this odorant receptor is highly conserved across all of these different species."

Keyword: Chemical Senses (Smell & Taste)
Link ID: 6912 - Posted: 02.22.2005

A study by UCLA neuroscientists featuring functional magnetic resonance imaging and a well-stocked tea service suggests for the first time that mirror neurons help people understand the intentions of others -- a key component to social interaction. Reporting Feb. 22 in the online edition of PLoS Biology, the UCLA team found that pre motor mirror neuron areas of the brain -- areas active during the execution and the observation of an action -- ascribe intentions to actions when presented within a context. Previously, these neurons were thought to be involved only in action recognition. In addition to expanding knowledge of how the brain functions, the findings support a growing body of evidence that imitation-based forms of treatments in patients with autism and similar disorders may help stimulate the function of these neurons, helping these patients improve their ability to understand the intentions of others and empathize with their thoughts and feelings. "Understanding the intentions of others while watching their action is a fundamental building block of social behavior," said principal investigator Dr. Marco Iacoboni, an associate professor in-residence of psychiatry and biobehavioral sciences at the UCLA Neuropsychiatric Institute's Ahmanson Lovelace Brain Mapping Center and the David Geffen School of Medicine at UCLA. "Our findings show for the first time that intentions behind actions of others can be recognized by the motor system using a mirror mechanism in the brain. The same area of the brain responsible for understanding behavior can predict behavior as well."

Keyword: Vision
Link ID: 6911 - Posted: 02.22.2005

Roxanne Khamsi Forget the taste of your meal, how does it sound? That's the question that termites ask themselves when chomping into wood, an Australian study suggests. It seems that these insects choose what to eat according to the way each piece of wood vibrates in response to their gnashing jaws. The finding could lead to new approaches to controlling termite damage, say researchers. The scientists examined the feeding behaviour of the drywood termite species Cryptotermes domesticus, which thrives in several continents. Close relatives in the Kalotermes termite genus wreak havoc on homes in Europe. Scientists know that C. domesticus prefers eating small rather than large pieces of wood in the wild, but they were mystified about exactly how the termites made this choice. So the Australian group recorded the sound generated as termites tunnelled into pinewood, a common building material. "Almost all wood-eating pest termites find it very palatable... unfortunately," says Theodore Evans of the Commonwealth Scientific and Industrial Research Organisation in Canberra, Australia. Along with engineer Joseph Lai of the Australian Defence Force Academy in Canberra and his colleagues, Evans found that when termites chewed their way through a 20-millimetre-long wood block, the sound of their bites created a vibration of 7.2 kilohertz. Termites in a similar block that was 160 millimetres long generated a slower vibration at 2.8 kilohertz, which would match a high F note from a xylophone. ©2005 Nature Publishing Group

Keyword: Hearing; Pain & Touch
Link ID: 6910 - Posted: 06.24.2010