St. Louis, -- Severe calorie restriction prevents certain aging-related changes in the brain, including the accumulation of free radicals and impairments in coordination and strength, according to a mouse study at Washington University School of Medicine in St. Louis. However, the dietary changes did not seem to prevent mice from developing some cognitive deficits associated with age, such as declines in memory. The study will be presented at 3 p.m. PT on Sunday, Oct. 24 at Neuroscience 2004, the Society for Neuroscience's 34th Annual Meeting in San Diego. "Our findings help us understand the processes underlying both normal aging and calorie restriction benefits," says principal investigator Laura L. Dugan, M.D., associate professor of neurology, of medicine and of anatomy and neurobiology. "If some aspects of aging are influenced by free radical damage, we may be able to prevent or reverse these impairments." Though numerous studies have shown severe calorie restriction helps animals live longer and resist some effects of aging, scientists still do not know why. One theory suggests a restrictive diet decreases the effect of free radical damage.

Keyword: Alzheimers; Obesity
Link ID: 6301 - Posted: 10.25.2004

By Jennifer Viegas, Discovery News A University of Florida scientist has created a living "brain" of cultured rat cells that now controls an F-22 fighter jet flight simulator. Scientists say the research could lead to tiny, brain-controlled prosthetic devices and unmanned airplanes flown by living computers. And if scientists can decipher the ground rules of how such neural networks function, the research also may result in novel computing systems that could tackle dangerous search-and-rescue jobs and perform bomb damage assessment without endangering humans. Additionally, the interaction of the cells within the lab-assembled brain also may allow scientists to better understand how the human brain works. The data may one day enable researchers to determine causes and possible non-invasive cures for neural disorders, such as epilepsy. For the recent project, Thomas DeMarse, a University of Florida professor of biomedical engineering, placed an electrode grid at the bottom of a glass dish and then covered the grid with rat neurons. The cells initially resembled individual grains of sand in liquid, but they soon extended microscopic lines toward each other, gradually forming a neural network — a brain — that DeMarse says is a "living computational device." Copyright © 2004 Discovery Communications Inc.

Keyword: Robotics
Link ID: 6300 - Posted: 06.24.2010

COLUMBUS, Ohio – Inebriated bees could give researchers better insight into alcohol's effects on human behavior, a new study suggests. "Alcohol affects bees and humans in similar ways – it impairs motor functioning along with learning and memory processing," said Julie Mustard, a study co-author and a postdoctoral researcher in entomology at Ohio State University. Researchers gave honey bees various levels of ethanol, the intoxicating agent in liquor, and monitored the ensuing behavioral effects of the drink – specifically how much time the bees spent flying, walking, standing still, grooming and flat on their backs, so drunk they couldn't stand up. The researchers also measured the level of ethanol in the bees' hemolymph – the circulatory fluid of insects that's akin to blood. Not surprisingly, increasing ethanol consumption meant bees spent less time flying, walking and grooming, and more time upside down. The appearance of inebriation occured sooner for bees that were given a larger dose of ethanol. Also, blood ethanol levels increased with time and the amount of ethanol consumed.

Keyword: Drug Abuse
Link ID: 6299 - Posted: 06.24.2010

Treating children with anti-psychotic drugs may increase the risk of a condition which leads to diabetes and heart disease, research suggests. A team from Johns Hopkins University looked at 'atypical' antipsychotics, used to treat behavioural problems such as manic depression and schizophrenia. They found their use may trigger insulin resistance. The research was presented to a meeting of the American Academy of Child and Adolescent Psychiatry. Considerable weight gain is a common side effect of atypical antipsychotic medications - and is also one of the many factors that can contribute to insulin resistance. All six children on moderate or high doses of one of these drugs, and three of five children on low doses, had evidence of insulin resistance. This is a condition in which the body cannot properly use the insulin it produces. Lead researcher Dr Mark Riddle said: "The insulin resistance seen in these children was greater than what would be expected from weight gain alone, suggesting there is a factor distinct from excess weight that directly induces insulin resistance." (C)BBC

Keyword: Schizophrenia; Development of the Brain
Link ID: 6298 - Posted: 10.23.2004

New Haven, Conn.--Estrogen treatment had less beneficial effect on memory in female mice that raced on running wheels and played with other toys than in mice raised in non-stimulating environments, according to a Yale study published this month. "We saw no beneficial effect of estrogen in the animals in cognitively and physically stimulating environments (also known as enriched environments)," said Karyn Frick, assistant professor of psychology and principal investigator on the study. "This fits in nicely with human data and might help to explain why studies of hormone replacement therapy (HRT) do not show beneficial effects for all women. Most studies of HRT use very well-educated women. These results might spur researchers to include a broader population with a greater variation in education and socioeconomic status." All of the mice lived in standard housing conditions that contained other mice and no toys. However, enriched mice spent three hours each day in larger cages with running wheels, tubes, and other mouse toys. The toys were varied from day to day. At 10 weeks of age, the ovaries of the mice were removed to simulate the long-term estrogen losses seen in menopause. At six months of age, the mice were then treated with estrogen or a control substance and were tested in tasks measuring spatial memory and memory for objects.

Keyword: Hormones & Behavior; Learning & Memory
Link ID: 6297 - Posted: 10.23.2004

An international research team, led by scientists at the National Institute on Aging (NIA), has discovered a gene, which when mutated, causes Parkinson’s disease in some families. Although Parkinson’s disease is usually not inherited, the discovery of this gene and further study of how it works could open up new avenues of research for preventing or delaying the onset of the disease. In research, the study of rare familial forms of a disease has often led to major insights into the pathogenesis of more common forms. The finding was published online by Neuron on October 22, 2004. The collaborative work was spearheaded by Andrew Singleton, Ph.D., at the NIA, Jordi Perez-Tur of the Institut de Biomedicina de Valencia in Spain, and Nick W. Wood of the Institute of Neurology in London. The NIA is a part of the National Institutes of Health (NIH) at the U.S. Department of Health and Human Services. "Parkinson's disease has a devastating impact upon individuals," says Elias A. Zerhouni, M.D., Director of the NIH. "This finding provides scientists with important new information about genetic mutations that underlie this disease, giving us new understanding about molecular mechanisms. Ultimately, this research will help in the development of targeted interventions that could actually alter the course of this disabling disease."

Keyword: Parkinsons; Genes & Behavior
Link ID: 6296 - Posted: 06.24.2010

By Peter Mombaerts Rarely do scientific studies claim that something is not the case. Rarer still do negative results appear in top-tier journals. Yet two recent papers in Nature describe what olfactory sensory neurons do not do.1,2 The olfactory system is often compared to the immune system. The key cell types in each system, the olfactory sensory neuron (OSN) and the lymphocyte, can detect a wide variety of chemicals, both natural and synthetic. Chemical recognition by these cells is specific and sensitive, so many odorant receptors (ORs)3 and antigen receptors are needed to cover the spectrum of chemical structures. It has been well established that each B or T lymphocyte expresses a single antigen receptor--an antibody or T-cell receptor. Analogously, each vertebrate OSN is thought to express a single OR gene. Lymphocytes restrict antigen receptor gene expression by genome modification, and many believed that OSNs did likewise. Now we1 and others2 claim that OR genes do not undergo irreversible genomic alterations in OSNs. With this hypothesis disproved, we may need to reassess the dogma that a single OSN expresses just one OR gene. © 2004, The Scientist LLC, All rights reserved.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 6295 - Posted: 06.24.2010

By David Secko A brain without glutamate, the major excitatory neurotransmitter in mammals, is quite literally unthinkable. Yet, knockout mice lacking the crucial vesicular glutamate transporter, VGLUT1, can live for up to a few months. This unexpected finding has enabled two research groups to investigate the function of VGLUT1. With potential links to learning and memory, as well as neurological diseases such as epilepsy, approaching glutamate transmission through the protein believed to load it into vesicles provides a useful starting point. "It is, so to speak, the fuel needed to make vesicle release recognized," says Christian Rosenmund at Baylor College of Medicine, Houston. Mice lacking this glutamate transporter survive, likely through the action of the isoform VGLUT2, but soon suffer from progressive neurological decline, blindness, poor coordination, and ultimately death. While not all the results appear to match up, the knockouts are lending insight into vesicle loading and neural development. "The knockouts enabled us to compare the behavior of VGLUT1 and 2 synapses," says Robert Edwards, University of California, San Francisco. A vesicular glutamate transporter proved difficult to identify. But in 2000, Rosenmund, Edwards, and their respective colleagues independently realized that it had been masquerading as an inorganic phosphate transporter.1 Renamed VGLUT1, the protein could actively transport glutamate into synaptic vesicles using a proton electrochemical gradient. Soon after VGLUT1's identity materialized, two isoforms, VGLUT2 and VGLUT3, were found. © 2004, The Scientist LLC, All rights reserved.

Keyword: Learning & Memory
Link ID: 6294 - Posted: 06.24.2010

By Jill U. Adams Communication between neurons--the stuff of our senses, emotions, and memories, as well as motor and visceral control--relies on chemical messengers. Packaged into tiny membrane-enclosed vesicles, neurotransmitters are delivered when a nerve impulse induces exocytosis. In addition to delivering the message to the receiving neuron, neurotransmission results in changes to the sending neurons, which lose transmitter-loaded vesicles and grow larger as spent vesicles are incorporated into the plasma membrane. Synaptic vesicle recycling resolves both of these changes by pinching off new vesicles from the cell surface for reloading. Often overlooked as mere housekeeping, synaptic vesicle recycling is crucial to neuronal preparedness. The number of vesicles in the releasable pool must be maintained. With biophysical methods allowing study of single vesicle events even in small nerve terminals, recycling research is intensifying as scientists propose mechanisms by which membrane segments are retrieved for reuse. Stimulating much of the new work is the kiss-and-run hypothesis: A vesicle fuses with the cell surface just enough to allow neurotransmitters to flow into the synaptic cleft, and then pinches off to return to the intracellular vesicle pool. Just like the returnable glass soda bottles from yesteryear, the vesicle maintains its membrane shell and simply needs to be refilled. The classical pathway is more akin to melting down bottles for remanufacturing. Opened vesicle membranes collapse into the plasma membrane and their components move to an offsite recycling facility of sorts where sorting and endocytosis occur via clathrin- coated pits. © 2004, The Scientist LLC, All rights reserved.

Keyword: Drug Abuse
Link ID: 6293 - Posted: 06.24.2010

By Bruce Lieberman UNION-TRIBUNE STAFF WRITER University of California San Diego professor Mark Ellisman, shown in his office with an enlarged image of a cerebellum scan as a backdrop, is coordinating a nationwide effort to build a database on neuroanatomy and brain diseases. In a lab at UCSD, Don Cleveland works on Lou Gehrig's disease. Fred Gage, at the Salk Institute, looks at how the brain remodels and repairs itself. A few blocks north on Torrey Pines Road, Evan Snyder of The Burnham Institute studies how stem cells might someday replace nerve cells ravaged by Parkinson's disease. These scientists and many others have built San Diego into a world center for brain research. Tomorrow, they will be joined by an estimated 30,000 researchers gathering in San Diego for the 34th annual meeting of the Society for Neuroscience. The conference, which will continue through Wednesday, will profile the latest discoveries about how the brain develops, grows and ages; the biology behind depression, addiction and schizophrenia; the science of consciousness; what drives brain diseases; and many other topics. © Copyright 2004 Union-Tribune Publishing Co.

Keyword: Miscellaneous
Link ID: 6292 - Posted: 06.24.2010

Common prostate cancer therapy disrupts brain's hippocampal memory system PORTLAND, Ore. - Oregon Health & Science University researchers studying how testosterone deprivation affects verbal memory found that men undergoing the prostate cancer therapy forget things faster than their healthy counterparts. Scientists in the OHSU School of Medicine's departments of Behavioral Neuroscience and Medicine, and the OHSU Cancer Institute, in a study to be presented Sunday to the Society for Neuroscience in San Diego, found that word retention drops sharply after only two minutes among men undergoing testosterone deprivation therapy. However, initial learning of the words, or encoding, was the same for testosterone-deprived and healthy men, according to the study titled "Androgen ablation impairs hippocampal-dependent verbal memory processes." Men who have undergone testosterone deprivation "are able to encode these words well, and if I ask them immediately, they can recall them as easily as non-hormone-deprived men," said Joseph Bussiere, a graduate student in behavioral neuroscience and the study's lead author. "But after only two minutes, there's a marked drop-off. When you stretch the time between encoding and retrieval, that's where the problem lies." © 2001-2004, Oregon Health & Science University

Keyword: Learning & Memory; Hormones & Behavior
Link ID: 6291 - Posted: 06.24.2010

Researchers have produced strong evidence that older fathers are more likely to have children who develop schizophrenia. The finding adds weight to the theory that accumulating mutations in the sperm are to blame. Sweden's Karolinska Institute and Bristol University estimate older fathers could account for 710 cases in England and Wales in 2002. The study is published in the online edition of the British Medical Journal. The researchers analysed the medical records of over 700,000 people born between 1973 and 1980. They found that, even after taking into consideration other factors, people born to older fathers were at increased risk of developing schizophrenia. They calculated that overall 15.5% of cases of schizophrenia seen in the group may have been due to the patient having a father who was aged over 30 years at their birth. The association seemed to be relatively specific to schizophrenia compared with other related forms of psychosis. It was also stronger in those with no family history of the disorder. The researchers argue that the key is the accumulation of mutations in older fathers' sperm. It is known that spontaneous genetic errors are more likely to occur in sperm and egg cells produced by older people - a phenomenon known as age-related aneuploidy. In England and Wales the average paternal age has increased from 29.2 years in 1980 to 32.1 in 2002. (C)BBC

Keyword: Schizophrenia
Link ID: 6290 - Posted: 10.22.2004

By JANE GROSS Lisa Krieger proved herself the equal of any presidential advance team in planning a first communion for her daughter, Gina, who is 8 years old and autistic. Months in advance, Ms. Krieger recruited other children to rehearse walking down the church aisle with Gina, and videotaped the procession so she could practice at home. She begged the nuns not to change Gina's place in line, because she might scream or wander off if faced with the slightest deviation. Ms. Krieger made sure Gina's communion dress was not itchy and let her try it on for a few minutes every day so she would not yank it off when the time came. She found a supplier of unconsecrated communion wafers so Gina would learn the taste and not spit the host back at the priest. And, on the big day in May, she stationed people throughout the church in Washington Township, N.J., to whisper instructions if Gina got confused. "The end result was she did beautifully," Ms. Krieger said. "But you have to think about everything, know what you're walking into and what's going to happen. I can't prepare her for everything, but I try to eliminate as many variables as possible." Copyright 2004 The New York Times Company

Keyword: Autism
Link ID: 6289 - Posted: 10.22.2004

When all the color drained from Judith Niosi's life, not even the childhood cheer of her seven-year-old son seemed to make life worth living. "At that time, I felt that he was better off without me because I just felt so hopeless and helpless," recalls the 37-year-old graphic artist. "And if I couldn't help myself, how could I help this child? I felt that I was doing him more damage being around him." Where joy ran from her so too did the energy required to accomplish seemingly simple tasks. "I couldn't get out of bed at all," she says. "I didn't want to do my hair. I didn't want to shower. I didn't want to do anything. It's not that I didn't want to, I couldn't. I didn't have the energy." Finally, she sought medical help. But that consisted of round after round of trial and error treatment with antidepressants that left her even more depressed and frustrated. A few agonizing months later, her doctors finally hit on a drug that cleared Niosi's mental fog. Researchers say Niosi's experience isn't by any means uncommon. Many psychiatrists lament the fact that there are currently no laboratory tools in place to determine who will—or who won't—succeed on the most popular antidepressant medications. © ScienCentral, 2000- 2004.

Keyword: Depression; Hearing
Link ID: 6288 - Posted: 06.24.2010

GAINESVILLE, Fla. --- A University of Florida scientist has grown a living "brain" that can fly a simulated plane, giving scientists a novel way to observe how brain cells function as a network. The "brain" -- a collection of 25,000 living neurons, or nerve cells, taken from a rat's brain and cultured inside a glass dish -- gives scientists a unique real-time window into the brain at the cellular level. By watching the brain cells interact, scientists hope to understand what causes neural disorders such as epilepsy and to determine noninvasive ways to intervene. As living computers, they may someday be used to fly small unmanned airplanes or handle tasks that are dangerous for humans, such as search-and-rescue missions or bomb damage assessments. "We're interested in studying how brains compute," said Thomas DeMarse, the UF professor of biomedical engineering who designed the study. "If you think about your brain, and learning and the memory process, I can ask you questions about when you were 5 years old and you can retrieve information. That's a tremendous capacity for memory. In fact, you perform fairly simple tasks that you would think a computer would easily be able to accomplish, but in fact it can't."

Keyword: Robotics
Link ID: 6287 - Posted: 10.22.2004

EVANSTON, Ill. --- Alzheimer's. Parkinson's. Lou Gehrig's. Huntington's. These neurodegenerative diseases exhibit loss of nerve function in different ways, from memory lapses to uncontrollable muscular movements, but it is now believed that these diseases share many common molecular mechanisms. A team of Northwestern University scientists, led by Richard I. Morimoto, John Evans Professor of Biology, has made a key discovery toward understanding one of these mechanisms. In studying toxic proteins involved in Huntington's disease, they discovered that the disease-causing protein severely interferes with the working of the proteasome, the cellular machine responsible for eliminating damaged proteins within the cell. The findings, which could lead to an understanding of how to prevent neurodegenerative diseases and to the development of effective drugs, will be published Oct. 27 in The EMBO Journal, a publication of the European Molecular Biology Organization. The proteasome is responsible for cell homeostasis. In healthy cells, proteins perform their function and then, with the help of the proteasome, disappear. If idle and damaged proteins remain, their presence can affect cell behavior.

Keyword: Huntingtons; ALS-Lou Gehrig's Disease
Link ID: 6286 - Posted: 10.22.2004

SAN FRANCISCO – Researchers are conducting a groundbreaking new study that may help stroke patients regain greater use of their hands or arms through treatment with electrical stimulation. Preliminary results of the feasibility study that precedes this new study have shown that the use of electrical stimulation, called motor cortex stimulation, may be both safe and effective, according to Robert Levy, M.D., Ph.D., a neurosurgeon at Northwestern Memorial Hospital in Chicago. Dr. Levy presented this feasibility trial data at the Congress of Neurological Surgeons Wednesday in San Francisco. The trial showed that study participants – stroke survivors suffering impaired hand or arm movement – who underwent physical rehabilitation accompanied by motor cortex stimulation showed greater improvement than participants who received physical rehabilitation alone. Twenty-four subjects participated in the feasibility study, 12 in the electrical stimulation group and 12 in the control group. "Participants in the electrical stimulation group experienced meaningful motor recovery gains," Dr. Levy says. "It is our hope that by stimulating the surface of the brain we can permanently reverse paralysis and rekindle patients' function, returning them to their normal lifestyle," says Dr. Levy, who is a professor at the Feinberg School of Medicine at Northwestern University and who is leading the study at Northwestern Memorial, which is being conducted in tandem with the Rehabilitation Institute of Chicago. "Unfortunately, when patients have had a stroke, there is not much we can currently offer beyond physical rehabilitation to improve their motor functions."

Keyword: Stroke; Regeneration
Link ID: 6285 - Posted: 06.24.2010

Paula Gould The small group of genes long believed to cause Down syndrome are unlikely to be the real culprits, according to recent research in mice. The finding is bad news for those devising therapeutic strategies, whose job would be simplified if blame could be laid at the door of just a few genes. Down syndrome occurs in around 1 in 700 live births. The vast majority of people with the condition are born with three complete copies of chromosome 21 instead of two. But a small proportion of individuals with Down syndrome have only certain portions of chromosome 21 in triplicate. Although chromosome 21 contains over 200 genes, comparison of people with complete and partial repetition led researchers to believe that most features of Down syndrome are caused by a so-called 'critical region' of chromosome 21, which contains just 30 or so genes. This idea has held sway for the past 30 years. Now researchers have used genetically engineered mice to disprove the theory. They bred mice with one, two and three copies of the mouse equivalents of genes from the critical region of human chromosome 21. They then compared visible, Down-like characteristics of these animals, such as face, head and growth measurements, with those from a known mouse model of Down syndrome. ©2004 Nature Publishing Group

Keyword: Development of the Brain
Link ID: 6284 - Posted: 06.24.2010

Researchers at the University of California, San Diego (UCSD) School of Medicine have discovered the gene for a form of Joubert Syndrome, a condition present before birth that affects an area of the brain controlling balance and coordination in about 1 in 10,000 individuals. Their study, published in the November 2004 issue of the American Journal of Human Genetics*, pointed to mutations in a gene called AHI1 that lead to the production of a protein the scientists named Jouberin. Separate research by a team from Harvard Medical School concurrently identified the same gene in a paper published in the November 2004 issue of the journal Nature Genetics.** Both the UCSD and Harvard studies were published online prior to the print publications in November. The AHI1 gene mutation is responsible for a form of Joubert Syndrome manifested by absence of part of the cerebellum, the part of the brain controlling balance, and by excessive folding in the cerebral cortex, the part of the brain controlling consciousness and thought. The results from both UCSD and Harvard involved a gene-by-gene search of chromosome 6 DNA from three families studied by UCSD and three separate families studied by Harvard. Researchers believe the disorder linked to chromosome 6 is the most common of the three known forms of Joubert Syndrome.

Keyword: Genes & Behavior; Development of the Brain
Link ID: 6283 - Posted: 10.21.2004

Receptors in the brain that are highly sensitive to alcohol may function differently in a person with a family history of alcoholism, according to a Yale study published this month. The study included 45 healthy subjects, some with a family history of alcoholism and others with no family history. None of the study participants had a drinking problem. All of the participants were administered a placebo or ketamine, an anesthetic that induces alcohol-like effects. Their behavioral responses were then observed. People with a family history of alcoholism were less sensitive to ketamine. "This study confirms a hypothesis that people with a family history of alcoholism are more vulnerable to alcoholism because they are less likely to get the 'warning signs' of when to stop drinking," said Ismene Petrakis, M.D., associate professor of psychiatry. "In the right environmental and social context, the loss of a potentially important 'brake' on drinking may promote heavy drinking."

Keyword: Drug Abuse
Link ID: 6282 - Posted: 10.21.2004