May 12, 2006, 6:52 AM CT

Epstein-Barr Virus And Multiple Sclerosis

Scientists have found that patients with multiple sclerosis (MS) carry a population of immune cells that overreact to Epstein-Barr virus. The virus, which causes mononucleosis and may contribute to some cancers, has long been suspected to play a role in MS. However, the mechanism linking the virus to the disease was poorly understood.

Researchers believe that MS-which can cause vision problems, muscle weakness, and difficulty with coordination and balance-is a result of the immune system attacking the body's own nervous system. Not everyone who is infected with Epstein-Barr develops MS, but the results of the new study, reported in the June 2006, issue of the journal Brain, suggest that some individuals' uncommonly strong reaction to the virus may trigger the disease. The findings could lead to new therapeutic strategies for better control of the damage caused in this autoimmune disorder.

The culprit, the scientists say, may be a population of T cells that helps boost other components of the immune system in response to the virus. "What we discovered in the peripheral blood of the MS patients were T cells that appeared to be primed for action against EBV," said Nancy Edwards, an HHMI-NIH research scholar at the National Institutes of Health (NIH) and co-author of the paper, which was published in advance online.........

Posted by: Daniel      Permalink         Source

May 9, 2006, 0:00 AM CT

Nanotubes To Send Signals To Nerve Cells

Texas researchers have added one more trick to the amazing repertoire of carbon nanotubes -- the ability to carry electrical signals to nerve cells.

Nanotubes, tiny hollow carbon filaments about one ten-thousandth the diameter of a human hair, are already famed as one of the most versatile materials ever discovered. A hundred times as strong as steel and one-sixth as dense, able to conduct electricity better than copper or to substitute for silicon in semiconductor chips, carbon nanotubes have been proposed as the basis for everything from elevator cables that could lift payloads into Earth orbit to computers smaller than human cells.

Thin films of carbon nanotubes deposited on transparent plastic can also serve as a surface on which cells can grow. And as scientists at the University of Texas Medical Branch at Galveston (UTMB) and Rice University suggest in a paper reported in the recent issue of the Journal of Nanoscience and Nanotechnology, these nanotube films could potentially serve as an electrical interface between living tissue and prosthetic devices or biomedical instruments.

"As far as I know, we're the first group to show that you can have some kind of electrical communication between these two things, by stimulating cells through our transparent conductive layer," said Todd Pappas, director of sensory and molecular neuroengineering at UTMB's Center for Biomedical Engineering and one of the study's senior authors. Pappas and UTMB research associate Anton Liopo collaborated on the work with James Tour, director of the Carbon Nanotechnology Laboratory at Rice's Richard E. Smalley Institute for Nanoscale Science and Technology, Rice postdoctoral fellow Michael Stewart and Rice graduate student Jared Hudson.........

Posted by: Daniel      Permalink         Source

May 2, 2006, 0:14 AM CT

Does IQ drop with age?

If college students had to perform under conditions that mimic the perception deficits a number of older people have, their IQ scores would take a drop.

As people grow older, do they really lose intelligence or is something else happening that drives down IQ scores? It was a question that scientists asked in the lab during two coding experiments to test out their hypothesis that older people suffer perception problems that impair their abilities to perform well on intelligence tests.

Grover C. Gilmore, professor of psychology and dean of Case's Mandel School of Applied Social Sciences, led the National Institute of Health-funded investigation, "Age Effects in Coding Tasks: Componential Analysis and Test of the Sensory Deficit Hypothesis." Findings from the experiments are published in the recent issue of the American Psychological Association's journal, Psychology and Aging. Other researchers are Ruth A. Spinks and Cecil W. Thomas.

"Even subtle deficits, such as a reduction in spatial contrast sensitivity, can impair performance on intelligence tests," concludes Gilmore.

Perception deficits gradually appear over the life span of individuals and seem to reach problem levels in elderly adults and can greatly impact functions in people with dementia or other cognitive-impaired conditions.........

Posted by: Daniel      Permalink         Source

April 29, 2006, 9:43 AM CT

Neuroimaging Tools Available On Web

A roving band of five unnamed researcher participants-who traveled across the country to nine different sites to have their brains examined via MRI-has contributed to a first-of-its-kind neuroimaging dataset that will help researchers to standardize and calibrate imaging data for multisite studies for years to come. The dataset, known as the Function BIRN Phase I Traveling Subjects Dataset, is the latest of more than two dozen open-source data and software tools made available to researchers worldwide by the Biomedical Informatics Research Network (BIRN).

Created in 2001 with NCRR support, BIRN is a national consortium of 28 research institutions and 37 research groups dedicated to creating a usable cyberinfrastructure that shares and integrates data, expertise, and unique technologies from multiple disciplines and research institutions thereby enabling collaborations that address complex health-related problems. (For more information, see the NCRR Reporter, Fall 2003, BIRN Putting Heads Together in Cyberspace.) Initial efforts focus on neuroimaging data, but the tools and technologies developed by BIRN will ultimately be applicable to other disciplines.

Calibration across sites is important, because brain scans from a single individual can appear surprisingly dissimilar when collected using different MRI instruments and methodologies. "In fact, we found there is more variation between sites than there is between subjects," says Steven Potkin, professor of psychiatry at the University of California, Irvine, and head of a series of BIRN projects correlation to functional imaging. "Unless this can be corrected, there is no point in doing a multisite imaging study".........

Posted by: Scott      Permalink         Source

April 29, 2006, 9:24 AM CT

Daring To Take Risks and Reap the Rewards

Medical advances often originate with a flash of creativity and a tolerance for risk. Recognizing that the safe bet is not always the best path when pursuing scientific knowledge, NCRR funds Exploratory/Developmental Research Projects, known as R21 grants, to give researchers the freedom to pursue innovative, high-risk scientific ideas, methods, or technologies that may ultimately lead to significant health-related payoffs. For instance, neuroscientist Paul Thompson depended on R21 funding to develop sophisticated computational tools for imaging and analyzing how diseases or adverse events affect the brain. A different R21 grant allowed geneticist Carl Pinkert to create a unique animal model for studying mitochondria disease, which has broad implications for human health.

NIH created the R21 funding mechanism to provide up to two years of support for the early and conceptual stages of innovative research projects. NCRR funds R21 grants in two broad categories: biomedical technology and comparative medicine.

At the University of California, Los Angeles, Thompson and colleagues developed a novel computational framework that effectively stretches, contorts, and changes the geometry of highly detailed three-dimensional brain images obtained via magnetic resonance imaging (MRI). These manipulations allow researchers to overlap and meld multiple brain images, collected over time or from multiple individuals, and enable comparisons between normal and dysfunctional brains. To date, the images have clearly revealed the changes wrought by Alzheimer's disease, methamphetamine abuse, schizophrenia, and AIDS. "With R21 funding, we developed new mathematical methods for understanding the effects of disease," says Thompson, an associate professor of neurology. "These images are really snapshots of a disease spreading over time".........

Posted by: Scott      Permalink         Source

April 28, 2006, 0:13 AM CT

Stem Cell Technology For Spinal Cord Repair

Scientists believe they have identified a new way, using an advance in stem-cell technology, to promote recovery after spinal cord injury of rats, as per a research studypublished in today's Journal of Biology.

Researchers from the New York State Center of Research Excellence in Spinal Cord Injury showed that rats receiving a transplant of a certain type of immature support cell from the central nervous system (generated from stem cells) had more than 60 percent of their sensory nerve fibers regenerate. Just as importantly, the study showed that more than two-thirds of the nerve fibers grew all the way through the injury sites eight days later, a result that is much more promising than prior research. The rats that received the cell transplants also walked normally in two weeks.

The University of Rochester Medical Center, Rochester, N.Y., and Baylor College of Medicine, Houston, collaborated on the work. Scientists believe they made an important advance in stem cell technology by focusing on a new cell type that appears to have the capability of repairing the adult nervous system.

"These studies provide a way to make cells do what we want them to do, instead of simply putting stem cells into the damaged area and hoping the injury will cause the stem cells to turn into the most useful cell types," explains Mark Noble, Ph.D., co-author of the paper, professor of Genetics at the University of Rochester, and a pioneer in the field of stem cell research. "It really changes the way we think about this problem."........

Posted by: Daniel      Permalink         Source

April 24, 2006, 6:59 PM CT

More Than Just Packaging

University Park, Pa. - People commonly think of the skull as packaging for the brain and scientists commonly investigate them separately, but a team of scientists now thinks that developmentally and evolutionarily that the two are incontrovertibly linked.

The researchers, including biological anthropologists, physicians and a computer scientist, looked at the Computerized axial tomography scans and MRIs of infants with particular types of craniosynostosis - a condition where one or more of the sutures -- fibrous bands that connect the bones -- of the baby's skull close too early and deform the skull and brain.

"We are interested in understanding craniosynostosis," says Dr. Joan T Richtsmeier, professor of biological anthropology at Penn State."We would like to know why it happens, particularly when it is not part of a syndrome, but when it occurs alone".

The scientists report in a recent early online publication of the Journal of Experimental Zoology: Molecular and Developmental Evolution: "Our study represents the first empirical evidence of phenotypic integration of brain and skull in 3D, eventhough indirect evidence has been accumulating for years".

The scientists are also interested in understanding how the skull and brain change jointly through evolution. Vertebrate evolution shows a trend toward fewer skull and jaw bones and loss of some intercranial joints. While craniosynostosis is considered a pathology in modern humans, it shares with evolutionary history a reduction in cranial elements and coincident changes in the shape of the skull and brain.The scientists think that studying craniosynostosis could shed light on the joint evolution of the brain and skull.........

Posted by: Daniel      Permalink         Source

April 23, 2006, 10:49 PM CT

Alcoholism And Chronic Smoking Can Damage Brain

Alcoholism is usually associated with chronic smoking, and both alcohol and nicotine are believed to act on the same brain region. A study in the recent issue of Alcoholism: Clinical & Experimental Research builds upon prior research that identified four potential alcohol-sensitive genes in the prefrontal cortex, finding that smoking also influences the expression of these genes.

"Nicotine and alcohol are both addictive drugs," said Traute Flatscher-Bader, a postdoctoral research officer at the Alcohol Research Unit of the University of Queensland, Brisbane and corresponding author for the study. "They act on the same brain region, the 'drug reward pathway' or mesocorticolimbic system (MDS). The MDS contains the 'feel-good' neurotransmitter dopamine. Acute nicotine and alcohol cause an imbalance within the MDS by artificially increasing dopamine levels through direct and/or indirect modulation of dopaminergic neurons. While the long-term effect of alcoholism on the human brain has been investigated, surprisingly little is known about the long-term effect of nicotine on specific regions of the drug reward pathway in the human brain."

"Studies into the molecular changes that alcohol and smoking have on the body and especially the brain are crucial for understanding the disease state," said Nikki Zuvela, a doctoral student in molecular neuroscience at The University of Queensland. "There are actual molecular changes to parts of the brain involved in developing addiction; most importantly, within those centres known to mediate desire, craving, pleasure, self control, decision making, fear and emotion."........

Posted by: Janet      Permalink         Source

April 23, 2006, 10:42 PM CT

Attention shoppers: Neurons that encode the value of different goods

Scientists at Harvard Medical School (HMS) report in the April 23 issue of Nature that they have identified neurons that encode the values that subjects assign to different items. The activity of these neurons might facilitate the process of decision-making that occurs when someone chooses between different goods.

"We have long known that different neurons in various parts of the brain respond to separate attributes, such as quantity, color, and taste. But when we make a choice, for example: between different foods, we combine all these attributes--we assign a value to each available item," says Camillo Padoa-Schioppa, PhD, HMS research fellow in neurobiology and lead author of the paper. "The neurons we have identified encode the value individuals assign to the available items when they make choices based on subjective preferences, a behavior called 'economic choice.'".

Everyday examples of economic choice include choosing between working and earning more or enjoying more leisure time, or choosing to invest in bonds or in stocks. Such choices have long been studied by economists and psychology experts. In particular, research in behavioral economics shows that in numerous circumstances, peoples' choices violate the criteria of economic rationality. This motivates a currently growing interest for the neural bases of economic choice--an emerging field called "neuroeconomics." In general, it is believed that economic choice involves assigning values to available options. However, the underlying brain mechanisms are not well understood.........

Posted by: JoAnn      Permalink         Source

April 20, 2006, 0:24 AM CT

New Genetic Cause Of Alzheimer's Disease Discovered

Scientists from the Flanders Interuniversity Institute for Biotechnology (VIB) connected to the University of Antwerp are the first to show that the quantity of amyloid protein in brain cells is a major risk factor for Alzheimer's disease. Amyloid protein has already been known to be the primary component of the senile plaques in the brains of patients. The new discovery demonstrates that the greater the quantity of the protein that is produced, the younger the dementia patient is.

Alzheimer's disease.

Alzheimer's disease is a memory disorder that affects up to 70% of all dementia patients. In Belgium, about 100,000 people suffer from this disease. The disease gradually destroys brain cells in the deep areas of the brain that are responsible for memory and knowledge. Ever since the disease was first reported by Alois Alzheimer - 100 years ago now - researchers have been searching diligently for ways to treat it.

Amyloid plaque formation plays a key role.

Genetic research has previously shown a direct correlation between amyloid protein and the development of senile plaques and loss of cells. Amyloid protein originates when it is cut by enzymes from a larger precursor protein. In very rare cases (fewer than 1 in 1000 patients), mutations appear in that amyloid precursor protein, causing it to change shape and be cut differently. The amyloid protein that is formed now has different characteristics, causing it to begin to stick together and precipitate as amyloid plaques. The development of amyloid plaques in the brain tissue of Alzheimer patients is a central factor in the search for a treatment for Alzheimer's disease.........

Posted by: Daniel      Permalink         Source