August 31, 2006, 4:57 AM CT

Juices Reduces Alzheimer's Risk

In a large epidemiological study, scientists observed that people who drank three or more servings of fruit and vegetable juices per week had a 76 percent lower risk of developing Alzheimers disease than those who drank juice less than once per week.

The study by Qi Dai, M.D., Ph.D., assistant professor of Medicine, and his colleagues appears in the recent issue of The American Journal of Medicine.

The scientists followed a subset of subjects from a large cross-cultural study of dementia, called the Ni-Hon-Sea Project, which investigated Alzheimers disease and vascular dementia in older Japanese populations living in Japan, Hawaii and Seattle, Wash.

For the current study, called the Kame Project, the scientists identified 1,836 dementia-free subjects in the Seattle population and collected information on their dietary consumption of fruit and vegetable juices. They then assessed cognitive function every two years for up to 10 years.

After controlling for possible confounding factors like smoking, education, physical activity and fat intake, the scientists observed that those who reported drinking juices three or more times per week were 76 percent less likely to develop signs of Alzheimers disease than those who drank less than one serving per week.........

Posted by: Daniel      Permalink         Source

August 30, 2006, 4:55 AM CT

Repeated Alcohol Exposures Can Affect Brain

Scientists at the University at Buffalo studying the effects of alcohol on the brain, using zebrafish as a model, have identified several novel central nervous system proteins that are affected by chronic alcohol exposure.

They also confirmed the involvement of additional proteins previously suggested as targets of alcohol toxicity, and observed abnormal behavior in the fish resulting from chronic alcohol exposure.

Results of the research appeared in the Aug. 15 online edition of the European Journal of Pharmacology.

Five proteins were found to be overexpressed and three were found to be underexpressed. These proteins are believed to be involved in critical mechanisms such as programmed cell death, cholesterol balance, amino acid metabolism, oxidative stress and signal transduction.

"Identification of proteins that show selective changes in abundance after alcohol exposure has the potential to unlock new pathways both for understanding the mechanisms of alcoholism and alcohol toxicity, as well as its amelioration," said Richard A. Rabin, Ph.D., professor in the UB Department of Pharmacology and Toxicology and senior author on the study.

Senthilkumar Damodaran, doctoral student in pharmacology, is first author.

The study involved 16 long-fin striped zebrafish, in two trials of eight each, which were placed as a group in a tank with ethyl alcohol for four weeks. Rabin said the scientists chose zebrafish because they are easy to breed and maintain, their DNA sequences are similar to that of humans and they are sensitive to alcohol concentrations.........

Posted by: JoAnn      Permalink         Source

August 29, 2006, 9:50 PM CT

More than just pretty faces

You'll find more than faces in these places. Stanford University scientists have taken the closest look yet at a region of the brain that was believed to be devoted solely to face recognition and discovered that this particular patchwork of neurons does much more: It also responds to such objects as cars, animals and sculptures.

Current face perception theories suggest neurons in a portion of the brain called the fusiform gyrus light up in response to a face, leading scientists to refer to this region as the "fusiform face area." But a study would be reported in the recent issue of Nature Neuroscience reports that this area also shows a localized - albeit less extensive - response to more than just faces.

"We've looked at the fine structure of face-selective regions in the brain, and it argues against prevailing theories," said first author Kalanit Grill-Spector, PhD, assistant professor of psychology and a researcher in the Neuroscience Institute at Stanford.

Using high-resolution functional magnetic resonance imaging, Grill-Spector and his colleagues imaged regions of the brain at a magnification of 27 to 70 times smaller than a traditional fMRI scan. Like viewing a grain of sugar rather than the whole cube, this allowed the team to "zoom in" on a hybrid of neural patches, each of which responds to a different category of objects.........

Posted by: Daniel      Permalink         Source

August 29, 2006, 9:15 PM CT

Stress And Alzheimer's Disease

Stress hormones appear to rapidly exacerbate the formation of brain lesions that are the hallmarks of Alzheimer's disease, as per scientists at UC Irvine. The findings suggest that managing stress and reducing certain medications prescribed for the elderly could slow down the progression of this devastating disease.

In a study with genetically modified mice, Frank LaFerla, professor of neurobiology and behavior, and a team of UCI scientists observed that when young animals were injected for just seven days with dexamethasone, a glucocorticoid similar to the body's stress hormones, the levels of the protein beta-amyloid in the brain increased by 60 percent. When beta-amyloid production increases and these protein fragments aggregate, they form plaques, one of the two hallmark brain lesions of Alzheimer's disease. The researchers also observed that the levels of another protein, tau, also increased. Tau accumulation eventually leads to the formation of tangles, the other signature lesion of Alzheimer's. The findings are published in this week's issue of the Journal of Neuroscience.

"It is remarkable that these stress hormones can have such a significant effect in such a short period of time," LaFerla said. "Eventhough we have known for some time that higher levels of stress hormones are seen in individuals in the early stages of Alzheimer's, this is the first time we have seen how these hormones play such a direct role in exacerbating the underlying pathology of the disease".........

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August 28, 2006, 9:46 PM CT

Video Game For Stroke Rehabilitation

Engineers at Rutgers, The State University of New Jersey, have modified a popular home video game system to assist stroke patients with hand exercises, producing a technology costing less than $600 that may one day rival systems 10 times as expensive.

The Rutgers hand rehabilitation system is an example of virtual rehabilitation, which combines virtual reality computer-generated interactive visual environments in which users control actions in a lifelike way with traditional treatment techniques. Virtual rehabilitation gives therapists new tools to do their jobs more effectively and engages patients who may otherwise lack interest or motivation to complete normal exercise regimens.

The Rutgers engineers are describing their work at the fifth International Workshop on Virtual Rehabilitation taking place Aug. 29 and Aug. 30 in New York City.

"Virtual reality is showing significant promise for promoting faster and more complete rehabilitation, but the cost of a number of systems is still prohibitive for widespread deployment in outpatient clinics or patients' homes," said Grigore Burdea, professor of electrical and computer engineering and a noted inventor of virtual rehabilitation technology. "While it's essential to keep pursuing breakthrough technologies that will initially be costly, it's just as important that we find ways to make innovative therapys accessible to the a number of patients who need them".........

Posted by: Daniel      Permalink         Source

August 28, 2006, 9:21 PM CT

Pain Control Discovery

A newly discovered enzyme inhibitor, identified by scientists originally looking for biological pest controls, may lead to pain relief for sufferers of arthritis and other inflammatory diseases, say scientists at the University of California, Davis. The finding, hailed by a noted inflammatory disease expert "as the most important discovery in inflammation in more than a decade," may also reduce side effects linked to the painkiller, Vioxx.

Lead author Kara Schmelzer, a post-doctoral researcher in principal investigator Bruce Hammock's lab, tested the novel compounds on rodents and found them to be as potent at a low-dose as Vioxx and Celebrex, but without the changes in blood chemistry associated with heart attacks. Vioxx and Celebrex belong to a class of drugs known as Cox-2 inhibitors. The enzyme targeted by the newly discovered inhibitors is also found in humans. (Enzymes are proteins that speed up chemical reactions.).

"The reason this is so exciting is that this is a novel way to reduce inflammation, with a combination treatment," Schmelzer said. "We're going after a new enzyme target, not going after the Cox-2 inhibitors".

Their research is reported in a paper entitled "Enhancement of Antinociception by Coadministration of Nonsteroidal Anti-Inflammatory Drugs and Soluble Epoxide Hydrolase Inhibitors," reported in the current edition of Proceedings of the National Academy of Sciences.........

Posted by: Daniel      Permalink         Source

August 27, 2006, 7:05 PM CT

How brain cells categorize images?

Socks in the sock drawer, shirts in the shirt drawer, the time-honored lessons of helping organize one's clothes learned in youth. But what parts of the brain are used to encode such categories as socks, shirts or any other item, and how does such learning take place?

New research from Harvard Medical School (HMS) researchers has identified an area of the brain where such memories are found. They report in the advanced online Nature that they have identified neurons that assist in categorizing visual stimuli. They observed that the activity of neurons in a part of the brain called the parietal cortex encode the category, or meaning, of familiar visual images and that brain activity patterns changed dramatically as a result of learning. Their results suggest that categories are encoded by the activity of individual neurons (brain cells) and that the parietal cortex is a part of the brain circuitry that learns and recognizes the meaning of the things that we see.

"It was previously unknown that parietal cortex activity would show such dramatic changes as a result of learning new categories," says lead author David Freedman, PhD, HMS postdoctoral research fellow in neurobiology. "Some areas of the brain, especially the frontal and temporal lobes, have been linked to visual categorization. Since these brain areas are all interconnected, an important next step will be to determine their relative roles in the categorization process".........

Posted by: Daniel      Permalink         Source

August 25, 2006, 5:09 AM CT

Researchers Restore Memory Lost In Mice With Alzheimer's

Scientists at Columbia University Medical Center have successfully restored normal memory and synaptic function in mice suffering from Alzheimer's disease. The study was published recently on the website of the journal Cell.

Researchers at Columbia's Taub Institute for Research on Alzheimer's Disease and the Aging Brain have identified an enzyme that is mandatory for normal cognition but that is impaired in a mouse model of Alzheimer's. They discovered that mice regained the ability to form new memories when the enzyme's function was elevated.

The research suggests that boosting the function of this enzyme, known as ubiquitin C-terminal hydrolase L1 (Uch-L1), may provide a promising strategy for battling Alzheimer's disease, and perhaps reversing its effects.

In the new study, the Columbia scientists discovered that the enzyme Uch-L1 is part of a molecular network that controls a memory molecule called CREB, which is inhibited by amyloid beta proteins in people with Alzheimer's. By increasing Uch-L1 levels in mice that had Alzheimer's, they were able to improve the animals' ability to create new memories.

"Because the amyloid beta proteins that cause Alzheimer's may play a normal, important physiological role in the body, we can't destroy them as a treatment," explained Ottavio Arancio, M.D., Ph.D., Assistant Professor of Pathology at Columbia University Medical Center and co-principal investigator of the study with Michael Shelanski, MD, Ph.D., Chairman of the Department of Pathology at the Columbia University College of Physicians and Surgeons. "What makes this newly discovered enzyme exciting as a potentially effective treatment is that it restores memory without destroying amyloid beta proteins".........

Posted by: Daniel      Permalink         Source

August 23, 2006, 8:57 PM CT

How We Detect Sour Taste

A team headed by biologists from the University of California, San Diego has discovered the cells and the protein that enable us to detect sour, one of the five basic tastes. The scientists, who included scientists from the National Institute of Dental and Craniofacial Research, suggest that this protein is also the long-sought sensor of acidity in the cerebrospinal fluid.

The study, featured on the cover of the August 24 issue of the journal Nature, reports that each of the five basic tastes is detected by distinct taste receptors-proteins that detect taste molecules-in distinct cells. The team previously discovered the sweet, bitter and umami (savory) receptors and showed that they are found in separate cells, but some scientists have argued that sour and salty tastes, which depend on the detection of ions, would not be wired in the same way.

"Our results show that each of the five basic taste qualities is exquisitely segregated into different taste cells" explained Charles Zuker, a professor of biology at UCSD and a Howard Hughes Medical Institute Investigator, who headed the study. "Taken together, our work has also shown that all taste qualities are found in all areas of the tongue, in contrast with the popular view that different tastes map to different areas of the tongue."........

Posted by: Daniel      Permalink         Source

August 22, 2006, 6:52 PM CT

No more than two strokes

Having a stroke is bad enough. But having another one after surviving the first one is particularly bad, more than doubling a person's risk of dying in the next two years, a new study finds.

The risk of a second stroke is particularly high among members of the largest and fastest-growing subgroup of Latinos in the United States: Mexican-Americans. The new study finds that they are more likely than their non-Latino white neighbors to suffer another stroke in the first two years after living through one.

The study, reported in the Annals of Neurology by a team from the University of Michigan Stroke Program in conjunction with colleagues in Texas, highlights the importance of what doctors call 'secondary prevention.'

In other words, those who live through a stroke should get special attention from their physicians and other health professionals to reduce their risk of having another one. And, because of their extra risk of suffering another stroke, those efforts should be particularly stepped up in Mexican-Americans, the scientists say.

"This finding completes a picture that has been taking shape through research on ethnic differences in stroke," says lead author Lynda Lisabeth, Ph.D. "We know that Mexican-Americans have a higher overall risk of stroke, tend to have strokes starting at younger ages, and generally have a better chance of surviving their first stroke, compared with non-Hispanic whites. Now, by finding this higher rate of recurrence, we have a better idea of the overall burden of stroke in this population.".........

Posted by: Daniel      Permalink         Source