A protein characterized by researchers at Baylor College of Medicine plays an important role in communication between neurons. This protein is overactive (up-regulated) in children with Down's Syndrome. Identifying this protein - Dap160 — and its function is an important step in understanding how neurons communicate with one another, said Dr. Hugo Bellen, BCM professor of molecular and human genetics, a Howard Hughes Medical Institute investigator, and director of the program in developmental biology. The report appears in the July 22, 2004, issue of the journal Neuron. Dap 160 was found as part of a new screen developed in Bellen's laboratory. The screen revealed many genes involved in neuronal function and development, said Bellen. Dap160 stands for Dynamin-associated protein of 160 kD (kilodaltons). Dynamin is a protein that is crucial to the final portion of the synaptic process. Neurotransmitters are the chemicals that contain the message to be transmitted when neurons talk to each other or to other cells. These chemicals are contained in small vesicles inside nerve endings called synapses. When a nerve pulse invades the nerve ending, these vesicles fuse with the membrane at the tip of the nerve ending (called the synaptic membrane). At this point, vesicles release their contents so that a nearby cell receives the message.

Keyword: Miscellaneous
Link ID: 5869 - Posted: 06.24.2010

WEST LAFAYETTE, Ind. – New research from Purdue University shows that even when people who stutter are not speaking, their brains process language differently. "Traditionally, stuttering is thought of as a problem with how someone speaks, and little attention has been given to the complex interactions between neurological systems that underlie speaking," says Christine Weber-Fox, an assistant professor of speech sciences who is interested in the brain's involvement in language processing. "We have found differences in adults who stutter, compared to those who don't, in how the brain processes information when people are thinking about language but not speaking. For example, there was a significant delay in response time when subjects were given a complex language task. We also found that in people who stutter, certain areas of the brain are more active when processing some language tasks." Weber-Fox, a cognitive neuroscientist, teamed with Anne Smith, a professor of speech science who studies the neurophysiological bases of speech production, to study language and speech production systems. A series of studies were conducted to measure semantic (word meaning in sentence processing), grammatical and phonological (sounds of the language, such as rhyming) aspects of language.

Keyword: Language
Link ID: 5868 - Posted: 06.24.2010

—Powerful sonar equipment used by the United States and other navies poses a serious threat to entire populations of whales and other marine mammals, scientists at the International Whaling Commission (IWC) meeting here say in a report. The IWC's scientific committee said there was "compelling evidence" showing that mid-frequency sonar had particularly affected the rare deep-diving beaked whale, driving it to frequent beachings and death. The evidence is being used by a coalition of U.S. animal welfare groups to mount a legal case against the U.S. Navy to force them to adopt measures to "mitigate harm" to marine mammals. In 2003, they obtained an injunction to block the navy's use of low frequency sonar, said Joel Reynolds, a lawyer with one of the groups, the Marine Mammal Protection Program. "The scientific case for a connection between stranded and dying whales and their exposure to mid-frequency sonar is overwhelming," Reynolds said on the sidelines of the IWC meeting in Sorrento. Copyright © 2004 Discovery Communications Inc.

Keyword: Hearing
Link ID: 5867 - Posted: 06.24.2010

By JANET McCONNAUGHEY NEW ORLEANS -- Japanese children who had seizures during a "Pokemon" cartoon in 1997 have generally not had another one unless they already had epilepsy, researchers say. The TV show sent at least 685 Japanese viewers, mostly children, to emergency rooms with symptoms ranging from nausea and hyperventilation to convulsions. They were apparently made sick by a scene with extremely rapid flashes of red and blue. To find out whether the incident had any lasting effects, Dr. Akihisa Okumura and colleagues in Nagoya sent questionnaires to doctors who had treated 103 "Pokemon" patients in the prefecture, or state, of Aichi. They got back results for 91 patients. Twenty-five had had at least one more convulsion in the five years since the "Pokemon" episode. They were divided almost evenly between those diagnosed with epilepsy and those who weren't. However, electroencephalograms revealed that 10 of the 13 who had not been diagnosed with epilepsy did, in fact, have the disease. Copyright © 2004, The Associated Press

Keyword: Epilepsy
Link ID: 5866 - Posted: 06.24.2010

Like a stereotypical husband who pretends not to hear his wife berating him, some male songbirds show no signs of recognizing the call of their long-term mate in laboratory settings. But recent work with these animals finds that they can, in fact, differentiate their mate's voice but will react to it only in certain social situations. Zebra finches are monogamous songbirds from Australia that fly in large flocks. As a result, couples routinely lose visual contact of each other and use calls to keep in touch. Whereas the female zebra finch clearly responds to the sound of her partner, the reciprocal behavior had not been observed in the male. Clémentine Vignal of Jean Monnet University in Saint-Etienne, France, and her colleagues acoustically analyzed the calls of seven female finches to see whether they had distinguishing characteristics. The results, published today in the journal Nature, demonstrated significant variation in the songs of the female birds, implying that the males could in all likelihood identify their sweethearts if they put their minds to it. To test this hypothesis, the researchers observed the reactions of male zebra finches while recordings of their mates were played back. Unlike previous setups in which the male was alone in a cage, the team placed other zebra finches nearby. As in previous experiments, the male made no display of recognition to his mate's voice in the company of either two males or a male and female who were not mates. Interestingly, however, when a mated couple was in the next cage, the male made it clear that he knew his mate's voice by nearly doubling the rate of his own calls. © 1996-2004 Scientific American, Inc

Keyword: Sexual Behavior
Link ID: 5865 - Posted: 06.24.2010

Six-year-old Nathan Neisinger suffered serious burns when he accidentally pulled a pot of boiling water onto himself. "He had third degree burns and they were over 31 percent of his body," says his mother, Heidi. "His whole entire chest, his back, his legs, part of his foot, had third degree burns all over them. They had to do skin grafting; they had to take skin off of his behind, off of the back of his legs." Besides skin grafts, Nathan has endured months of wound care and more pain than safe doses of narcotics can alleviate. "The care is very often more painful than the injury itself," says David Patterson, a psychologist and pain expert at Harborview Medical Center in Seattle, where Nathan spent 51 days after being airlifted there for his injuries. "Typical care involves removing bandages and then scrubbing the wound, and for some patients, you do that once or twice a day, for days, weeks, and even months." And then there was the physical therapy to stretch his scarred skin. "The actual process of going through that physical therapy is often very extensive," says Patterson. "You can hear some ripping and cracking. It can be anxiety-producing to anyone, much less a six-year-old." © ScienCentral, 2000- 2004.

Keyword: Pain & Touch
Link ID: 5864 - Posted: 06.24.2010

Howard Hughes Medical Institute (HHMI) researchers have identified subtle defects in a single gene that underlie a hereditary form of age-related macular degeneration, the leading cause of irreversible vision loss in the developed world. Although the genetic mutations discovered by the researchers affect only about two percent of patients with the disorder, the findings offer important insights for researchers who seek to understand age-related macular degeneration (AMD). “The clinical entity that we call AMD is actually as many as fifty diseases,” said the study's lead author, HHMI investigator Edwin M. Stone, who is at the University of Iowa Carver College of Medicine. “They simply look so similar that clinicians call them the same thing. Because of such complexity, we don't understand the molecular mechanisms of the disease very well, and this has limited our ability to develop preventive therapy for it. “Looking for genetic causes of AMD is potentially very meaningful because it will help us identify the mechanisms of the disease,” he said. “Knowing the genetic bases of AMD would also enable us to create an animal model that could be used to test therapies. And, if we understood several of the mechanisms, we could potentially divide the patient population into clinically relevant subgroups, so that we could direct specific treatments to those most likely to benefit from them.” © 2004 Howard Hughes Medical Institute.

Keyword: Vision; Genes & Behavior
Link ID: 5863 - Posted: 06.24.2010

The hand you favour as a 10-week-old fetus is the hand you will favour for the rest of your life, suggests a new study. The finding comes as a surprise because it had been thought that lifelong hand preferences did not develop until a child was three or four years old. A team led by Peter Hepper of the Fetal Behaviour Research Centre at Queen's University, Belfast in the UK reached this conclusion after studying ultrasound scans of 1000 fetuses. In one study, nine out of 10 fetuses at 15 weeks' gestation preferred to suck their right thumbs. Hepper's team followed 75 of those fetuses after birth, and found that at 10 to 12 years old all 60 of the right thumb-suckers were right-handed, while 10 of the 15 left thumb-suckers were left-handed and the rest right-handed. At 10 weeks old, even before they suck their thumbs, fetuses wave their arms about. A second study found that most prefer to wave their right arm, a preference that persisted until 24 weeks, after which the fetus is too cramped to move. Hepper reported the findings at the Forum of European Neuroscience in Lisbon, Portugal, earlier in July. © Copyright Reed Business Information Ltd.

Keyword: Laterality
Link ID: 5862 - Posted: 06.24.2010

Michael Hopkin It is good political strategy to surround your territory with the weak. And it turns out that a species of Australian crab is expert at working out how worthwhile it is to protect its feeble neighbours for the sake of a quiet life. If the next-door territory comes under attack, a crab will fight to help defend it, report Patricia Backwell and Michael Jennions of the Australian National University in Canberra. But the crustacean weighs up the odds first, and only provides backup for neighbours who are smaller than itself. The researchers studied fiddler crabs (Uca mjoebergi) living on seaside mudflats in Darwin, Australia. These crab communities are densely packed and the average male marshals a territory just 10 centimetres across. "Everyone knows his neighbour," says Backwell. But not all males boast a bachelor pad, and lack of one can seriously hamper success with the ladies. Homeless crabs roam the community, attacking homeowners and attempting to steal their patch. ©2004 Nature Publishing Group

Keyword: Aggression; Evolution
Link ID: 5861 - Posted: 06.24.2010

Helen Pilcher Size may matter after all, when it comes to IQ. A brain imaging study suggests that human intellect is based on the volume of grey matter in certain brain regions, challenging alternative views about the basis of intelligence. Researchers have been trying to pinpoint the biological roots of intelligence for decades. More than 25 years ago, a weak correlation was found between IQ and overall brain size. Others have suggested that level of intelligence is due to the size of the frontal lobe. Now, however, a common view is that more subtle characteristics are likely to be involved, such as the speed at which nerve impulses travel in the brain, or the number of neuronal connections present. This study challenges that idea, suggesting that the volume of certain brain regions may have an effect after all. Richard Haier from the University of California, Irvine, and colleagues used magnetic resonance imaging to measure the amount of grey matter in the brains of 47 adults, who also took standard IQ tests. ©2004 Nature Publishing Group

Keyword: Intelligence
Link ID: 5860 - Posted: 06.24.2010

BY SANDRA GUY SUN-TIMES COLUMNIST Advertisement The brain's inner workings hold mysteries that Chicago area researchers love to try to solve. Researchers at Northwestern University have found a quirky new step toward understanding short-term memory -- the kind of memory that lets us remember a telephone number that we won't need to use again just long enough to dial it. The prefrontal cortex, a part of the brain that helps people plan and memorize, and control their emotions, also governs short-term memory. Researchers have long known that the many kinds of neurons in the cortex can work together to create specific patterns of excitation that carry meaning and information. The Northwestern researchers built a rough model of how this ensemble of neurons might work together. They assumed that the neurons are interconnected through a network that operates like a small world, and they saw a wave of activity that kept going around the intricate paths inside the network. Such a small-world network operates like a tourist trying to get around in New York City. Researchers previously thought the visitor could do one of two things: either walk block by block in a long and tedious journey, or spend all the time using the shortcuts provided by the subway. Copyright 2004, Digital Chicago Inc.

Keyword: Learning & Memory
Link ID: 5859 - Posted: 07.22.2004

Researchers have now found that amphetamines diminish people's anticipation of rewards. Scans of subjects' brains when they were led to anticipate a cash reward--as well as psychological self-assessments--revealed them to be less positively aroused by such anticipation under the influence of dextroamphetamine. Amphetamines are popularly known as "go pills" among fighter pilots, who take them to reduce fatigue on long flights. What's more, the researchers also found that the subjects who took the amphetamine were not as negatively aroused when they anticipated losses, which led the scientist to theorize that such drugs might help "maintain motivation, even in the face of adversity." Brian Knutson, assistant professor of psychology and neuroscience at Stanford University, and his colleagues reported experiments in which they asked eight volunteers to perform a task in which they had to respond to shapes on a screen in return for anticipated cash rewards. The researchers gave the subjects doses of either dextroamphetamine or a placebo.

Keyword: Drug Abuse
Link ID: 5858 - Posted: 07.22.2004

COLUMBUS, Ohio – Believe it or not, a 5-year-old could beat most adults on a recognition memory test, at least under specific conditions, according to a new study. These findings run counter to what has been known for years from memory research – namely, that memory develops from early childhood to young adulthood, with young adults having much better memory than children. In one study, children were accurate 31 percent of the time in identifying pictures of animals they had seen earlier, while adults were accurate only 7 percent of the time. And the memory difference was not because adults already have their mind filled with appointments, to-do lists and other various grown-up issues. The memory accuracy of adults is hurt by the fact that they know more than children and tend to apply this knowledge when learning new information, the findings showed. “It’s one case where knowledge can actually decrease memory accuracy,” said Vladimir Sloutsky, co-author of the study and professor and director of the Center for Cognitive Science at Ohio State University.

Keyword: Learning & Memory; Development of the Brain
Link ID: 5857 - Posted: 06.24.2010

As dusk settles across the Belfast skyline, Joe Neeson whistles and calls down his racing pigeons. Joe doesn't count - he doesn't need to. After years looking after his tiny loft in the yard behind his west Belfast home, he knows every bird by name. So when Joe scanned the roof above the loft on the day of Linda's first race, he knew there was a bird missing. The young pigeon had been released more than 300 miles away in Penzance. And as darkness fell, Joe knew that Linda was not coming home. Seven hundred miles away across the North Sea, Linda was beginning what would be a year-long adventure. No-one knows for sure how Linda arrived at the petrol refinery at Mongstad - one of Europe's biggest ports. It seems likely though that the exhausted pigeon "jumped ship" in the fading light as she flew across the North Sea. Refinery workers found her cowering under clothes lockers and took pity on the bird which seemed close to death. A Norwegian television crew was at the refinery to record a wildlife film, and journalist Hans Gunnar Skarstein realised that the band on the pigeon's leg held the key to her identity. (C)BBC

Keyword: Animal Migration
Link ID: 5856 - Posted: 07.21.2004

Most Alzheimer’s drugs treat the symptoms of dementia. But, as this ScienCentral News video reports, a new tool may soon predict who will develop the disease even before symptoms occur. Like it or not, our brains start shrinking at around age 40. But an accelerated type of brain shrinkage occurs in people who go on to develop Alzheimer's disease or other types of dementia. Now, research is revealing that the rate of brain volume loss may help identify those with mild cognitive impairment who are at risk for developing dementia. "Mild cognitive impairment refers to people who are in a transition stage between normal cognition and being demented," explains Deniz Erten-Lyons, a neurologist at Oregon Health and Science University. "They have memory complaints, but these are not severe enough for clinicians to make a diagnosis of dementia. Dementia is a general word for people with problems in brain functions—memory problems, language problems—to a degree that it affects their ability to function in their day to day living." Erten-Lyons says magnetic resonance imaging (MRI) brain scans may predict who will progress from mild cognitive impairment to full-fledged dementia. Her lab compared the scans of 55 volunteers over the span of 14 years; none of the subjects suffered from mild cognitive impairment at the beginning of the study. Each person was examined twice a year, given tests to place them into three categories: intact cognition, mild cognitive impairment that was considered stable, and mild cognitive impairment that progressed into Alzheimer's disease. © ScienCentral, 2000- 2004.

Keyword: Alzheimers
Link ID: 5855 - Posted: 06.24.2010

Chimpanzees yawn in response to seeing other chimps yawn, reveals a new study. The discovery bolsters the idea that chimps are able to understand their own and others' state of mind. Catching a glimpse of a colleague yawning during an important meeting is enough to have most humans fighting to stifle a gape. And the impression that yawning is "contagious" has stood up to scientific scrutiny. When adult humans are shown videos of yawns, around 42 to 55 per cent also begin yawning. Why humans do it is still controversial, although one suggestion is that it may have evolved as a social cue to synchronise sleep amongst a group. Now a research team led by James Anderson at the University of Stirling in the UK has shown that chimpanzees also perform "contagious yawning". © Copyright Reed Business Information Ltd.

Keyword: Emotions; Sleep
Link ID: 5854 - Posted: 06.24.2010

Peter Aldhous British animal-rights protesters have won another victory, now that the lead contractor building a research facility at the University of Oxford has withdrawn from the project. The protesters' opponents condemn the campaign of intimidation that led to the contractor's move. But they argue that it represents a minor hiccup, rather than a signal that the protesters are winning their war to end experimentation on animals. Oxford officials say that the US$33.5-million facility, due to open next year, is vital to the future of research at the university. Most of the planned research would be on rodents, investigating conditions including cancer, heart disease and stroke. Some monkeys would also be used. The lab became the main focus for the attention of British animal rights activists after the University of Cambridge abandoned plans to build a primate research facility in January this year. That decision was in part due to the soaring costs of providing security in the face of repeated protests. Repeating the tactics employed in previous campaigns, protesters soon began targeting contractors building the Oxford lab. The offices of a company providing concrete were heavily vandalized. Activists also sent letters to the shareholders of the lead contractor, a company called Montpellier, purporting to be from its chairman. These urged shareholders to sell their stock to avoid reprisals from the animal rights movement. ©2004 Nature Publishing Group

Keyword: Animal Rights
Link ID: 5853 - Posted: 06.24.2010

CHICAGO – The risk of suicidal behavior is increased in the first month after starting antidepressants, and is similar among users of four antidepressant drugs, according to a study in the July 21 issue of The Journal of the American Medical Association (JAMA). According to background information in the article, considerable public attention recently has focused on the relation between use of antidepressants, especially selective serotonin reuptake inhibitors (SSRIs), and suicidal ideation (having thoughts of suicide or of taking action to end one's own life) and suicidal behaviors. SSRIs are antidepressant drugs that work by making available more serotonin, a chemical in the brain that is thought to play a key role in depression and anxiety. The use of antidepressant drugs among teenagers has been of particular concern. Hershel Jick, M.D., and colleagues with the Boston Collaborative Drug Surveillance Program, Boston University, estimated the relative risks of non-fatal suicidal behavior in patients in the United Kingdom starting treatment with the SSRIs fluoxetine and paroxetine and another antidepressant, amitriptyline--compared with patients starting treatment with a fourth drug, dothiepin, that is not available in the U.S. Amtriptyline and dothiepin belong to a class of drugs known as tricyclic antidepressants. Participants could have used only one of the antidepressants, and had to have received at least one prescription for the drug within 90 days before their index date (the date of suicidal behavior or ideation for cases, and the same date for matched controls).

Keyword: Depression
Link ID: 5852 - Posted: 06.24.2010

ATLANTA- Emory University scientists are using a combination of transgenic mouse models and viral vectors to clarify the role of a brain molecule called LR11 in Alzheimer's disease (AD). LR11 is a receptor for apoliporotein E, which is involved in cholesterol metabolism and has previously been linked to AD. Early studies suggest that LR11 regulates levels of beta amyloid, which is the primary protein comprising the senile plaques in the brains of Alzheimer's patients. Sara E. Dodson, BS, a neuroscience program graduate student in Emory University's Division of Biological and Biomedical Sciences, will present results of her team's research at the 9th International Conference of Alzheimer's Disease and Related Disorders in Philadelphia on July 20 at 12:30 pm. The Emory scientists already have used human brain tissue to show that LR11 is markedly reduced in patients with Alzheimer's disease. In their current experiments, they combined special viruses, called lentiviruses, to selectively reduce and enhance LR11 expression in mouse brains and cultured cells to study the function of LR11. Lentiviruses are special in their ability to infect neurons and permanently alter expression of certain genes by the infected cells. The Emory scientists successfully used these viruses to deliver artificial genes into neurons to control expression of LR11 in mouse brains. When this approach was used in cultured cells to reduce LR11 levels and mimic the situation in Alzheimer's brains, there was a marked increase in beta amyloid, suggesting that LR11 plays a key role in regulating levels of this important molecule.

Keyword: Alzheimers
Link ID: 5851 - Posted: 07.21.2004

By SANDRA BLAKESLEE People who do not want to wait for old age to shrink their brains and bring on memory loss now have a quicker alternative - abuse methamphetamine for a decade or so and watch the brain cells vanish into the night. The first high-resolution M.R.I. study of methamphetamine addicts shows "a forest fire of brain damage," said Dr. Paul Thompson, an expert on brain mapping at the University of California, Los Angeles. "We expected some brain changes but didn't expect so much tissue to be destroyed." The image, published in the June 30 issue of The Journal of Neuroscience, shows the brain's surface and deeper limbic system. Red areas show the greatest tissue loss. The limbic region, involved in drug craving, reward, mood and emotion, lost 11 percent of its tissue. "The cells are dead and gone," Dr. Thompson said. Addicts were depressed, anxious and unable to concentrate. The brain's center for making new memories, the hippocampus, lost 8 percent of its tissue, comparable to the brain deficits in early Alzheimer's. The methamphetamine addicts fared significantly worse on memory tests than healthy people the same age. Copyright 2004 The New York Times Company

Keyword: Drug Abuse; Brain imaging
Link ID: 5850 - Posted: 07.20.2004