May 6, 2008, 9:44 PM CT

Neurons duke it out for survival

The developing nervous system makes far more nerve cells than are needed to ensure target organs and tissues are properly connected to the nervous system. As nerves connect to target organs, they somehow compete with each other resulting in some living and some dying. Now, using a combination of computer modeling and molecular biology, neuroresearchers at Johns Hopkins have discovered how the target tissue helps newly connected peripheral nerve cells strengthen their connections and kill neighboring nerves. The study was reported in the April 18th issue of Science.

It was hard to imagine how this competition happens because the signal that leads cells to their targets also is responsible for keeping them alive, which begs the question: How do half of them die? says David Ginty, Ph.D., a professor of neuroscience and investigator of the Howard Hughes Medical Institute.

Target tissues innervated by so-called peripheral neurons coax nerves to grow toward them by releasing nerve growth factor protein, or NGF. Once the nerve reaches its target, NGF changes from a growth cue to a survival factor. In fact, when some populations of nerve cells are deprived of NGF they die. To further investigate how this NGF-dependent survival effect works the scientists looked for genes that are turned on by NGF in developing nerve cells......... Posted by: Daniel      Read more         Source

April 30, 2008, 5:55 PM CT

Salk study links diabetes and Alzheimer's disease

Diabetic individuals have a significantly higher risk of developing Alzheimers disease but the molecular correlation between the two remains unexplained. Now, scientists at the Salk Institute for Biological Studies identified the probable molecular basis for the diabetes Alzheimers interaction.

As per a research findings reported in the current online issue of Neurobiology of Aging, researchers led by David R. Schubert, Ph.D., professor in the Cellular Neurobiology Laboratory, report that the blood vessels in the brain of young diabetic mice are damaged by the interaction of elevated blood glucose levels characteristic of diabetes and low levels of beta amyloid, a peptide that clumps to form the senile plaques that riddle the brains of Alzheimers patients.

Eventhough the damage took place long before the first plaques appeared, the mice suffered from significant memory loss and an increase in inflammation in the brain. Eventhough the toxic beta amyloid peptide was first isolated from the brain blood vessels of Alzheimers patients, the contribution of pathological changes in brain vascular tissue to the disease has not been well studied, says Dave R. Schubert, Ph.D., professor and head of the Cellular Neurobiology Laboratory. Our data clearly describe a biochemical mechanism to explain the epidemiology, and identify targets for drug development......... Posted by: JoAnn      Read more         Source

April 28, 2008, 5:43 PM CT

Brain's Reaction to Potent Hallucinogen

Brain-imaging studies performed in animals at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory provide scientists with clues about why an increasingly popular recreational drug that causes hallucinations and motor-function impairment in humans is abused. Using trace amounts of Salvia divinorum - also known as "salvia," a Mexican mint plant that can be smoked in the form of dried leaves or serum - Brookhaven researchers observed that the drug's behavior in the brains of primates mimics the extremely fast and brief "high" observed in humans. Their results are now published online in the journal NeuroImage.

Quickly gaining popularity among teenagers and young adults, salvia is legal in most states, but is grabbing the attention of municipal lawmakers. Numerous states have placed controls on salvia or salvinorin A - the plant's active component - and others, including New York, are considering restrictions.

"This is probably one of the most potent hallucinogens known," said Brookhaven chemist Jacob Hooker, the lead author of the study, which is the first to look at how the drug travels through the brain. "It's really important that we study drugs like salvia and how they affect the brain in order to understand why they are abused and to investigate their medicinal relevance, both of which can inform policy makers."........ Posted by: Daniel      Read more         Source

April 24, 2008, 10:11 PM CT

How Neurons Generate Movement

When the eye tracks a bird's flight across the sky, the visual experience is normally smooth, without interruption. But underlying this behavior is a complex coordination of neurons that has remained mysterious to scientists. Now, UCSF scientists have broken ground in understanding how the brain generates this tracking motion, a finding that offers a window, they say, into how neurons orchestrate all of the body's movements.

The study, published in the April 24 issue of Neuron, reveals that individual neurons do not fire independently across the entire duration of a motor function as traditionally thought. Rather, they coordinate their activity with other neurons, each firing at a particular moment in time.

"Researchers have known that neurons that connect to muscles initiate movement in a coordinated fashion. But they have not known how the neurons we are studying - which coordinate these front-line neurons -- commit the brain to move the eyes,"says co-lead author David Schoppik, PhD, who conducted the study while a doctoral candidate in the laboratory of senior author Stephen Lisberger, PhD, at the University of California, San Francisco.

"For decades, researchers have been asking, 'Do the signals involve a handful of neurons or thousands? What is the nature of the commands?' The classical understanding has been that one class of neuron is responsible for one movement, such as generating eye movement to the left, and that it remains active across the entire duration of a behavior," he says......... Posted by: Daniel      Read more         Source

April 17, 2008, 8:26 PM CT

Breakthrough in migraine genetics

Migraine is the most common cause of episodic headache, and by far the most common neurological cause of a doctors visit. It affects some 15% of the population, including some 41 million people in Europe, and places a considerable burden on healthcare in both the developed and the developing world.

During the last few years, great strides have been made in discovering common genes influencing the susceptibility to common diseases, such as diabetes, Crohns disease and schizophrenia. However, no genes have yet been convincingly linked to migraine susceptibility, probably due to the high degree of variability of the disease phenotype combined with the lack of viable laboratory tests.

To address this problem, we developed a new analysis technique concentrating on different symptoms of migraine, says Professor Aarno Palotie (University of Helsinki, Finland, and the Sanger Institute, Cambridge, UK). The new technique was used in the large international study including 1700 migraine patients and their close relatives from 210 Finnish and Australian migraine families. The Finnish families had been ascertained through neurology clinics, while the Australian families had been collected through a twin study. An initial genome-wide microsatellite study was followed up by an independent targeted replication study......... Posted by: Daniel      Read more         Source

April 17, 2008, 7:28 PM CT

Slight Of Hand Is Not So Slight

Typing on a keyboard or scribbling on paper may be similar activities, but there is a significant difference in how the body moves, as per new motor development research.

"In language we start with letters that lead to syllables that lead to words, and we use grammar to put everything together," said Howard N. Zelaznik, a Purdue University professor of health and kinesiology. "One of the fundamental questions in motor control is whether there is an alphabet that guides movement.

"We wanted to know if discrete skills, which have a definite beginning and end, such as typing, are controlled identically to continuous skills, such as scribbling, which do not have such a clear beginning and end. Or, are continuous movements composed of a series of discrete movements that are knotted together? On both accounts, the answer is no".

Zelaznik was part of research team led by Viktor Jirsa, director of research at the Centre National de la Recherche Scientifique (CNRS) and a professor of movement sciences at the University of the Mediterranean in Marseilles, France, and Raoul Huys, a research associate at the Centre National de la Recherche Scientifique as well as at the University of the Mediterranean. Purdue graduate students Breanna Studenka and Nicole Rheaume also were part of the team. Their research findings were published Thursday (April 17) in the Public Library of Science's Computational Biology online journal......... Posted by: Daniel      Read more         Source

April 10, 2008, 9:23 PM CT

Wine may protect against dementia

There may be constituents in wine that protect against dementia. This is shown in research from the Sahlgrenska Academy at University of Gothenburg in Sweden.

The findings are based on 1,458 women who were included in the so-called Population Study of Women from 1968. When they were examined by physicians they were asked to report how often they drank wine, beer, and liquor by selecting from seven categories on a scale from never to daily. The scientists know nothing about how much they drank on each occasion, or how correct the estimates were. For each beverage the women reported having drunk more than once a month, they were classified as a consumer of that particular beverage.

Thirty-four years after the first study, 162 women had been diagnosed with dementia. The results show that among those women who reported that they drank wine a considerably lower proportion suffered from dementia, whereas this correlation was not found among those who had reported that they regularly drank beer or liquor.

The group that had the lowest proportion of dementia were those who had reported that the only alcohol they drank was wine, says Professor Lauren Lissner, who directs the study in collaboration with Professor Ingmar Skoog, both with the Sahgrenska Academy......... Posted by: Daniel      Read more         Source

March 27, 2008, 9:55 PM CT

Sniffing out danger

Each human nose encounters hundreds of thousands of scents in its daily travels perched front and center on our face. Some of these smells are nearly identical, so how do we learn to tell the critical ones apart? .

Something bad has to happen. Then the nose becomes a very quick learner.

New research from Northwestern University's Feinberg School of Medicine shows a single negative experience associated with an odor rapidly teaches us to identify that odor and discriminate it from similar ones.

"It's evolutionary," said Wen Li, lead author of the study and a postdoctoral fellow at the Cognitive Neurology and Alzheimer's Disease Center at the Feinberg School. "This helps us to have a very sensitive ability to detect something that is important to our survival from an ocean of environmental information. It warns us that it's dangerous and we have to pay attention to it."

The study will be published March 28 in the journal Science.

In the study, subjects were exposed to a pair of grassy smells which were nearly identical in their chemical makeup and perceptually indistinguishable. The subjects received an electrical shock when they were exposed to one scent, but not when they were exposed to the other similar one.

After being shocked, the subjects learned to discriminate between the two similar smells. This illustrates the tremendous power of the human sense of smell to learn from emotional experience. Odors that once were impossible to tell apart became easy to identify when followed by an aversive event......... Posted by: Daniel      Read more         Source

March 27, 2008, 9:50 PM CT

Key culprit in stroke brain cell damage

Scientists have identified a key player in the killing of brain cells after a stroke or a seizure. The protein asparagine endopeptidase (AEP) unleashes enzymes that break down brain cells' DNA, researchers at Emory University School of Medicine have found.

The results are reported in the March 28 issue of the journal Molecular Cell.

Finding drugs that block AEP may help doctors limit permanent brain damage following strokes or seizures, says senior author Keqiang Ye, PhD, associate professor of pathology and laboratory medicine at Emory.

When a stroke obstructs blood flow to part of the brain, the lack of oxygen causes a buildup of lactic acid, the same chemical that appears in the muscles during intense exercise. In addition, a flood of chemicals that brain cells commonly use to communicate with each other over-excites the cells. Epileptic seizures can have similar effects.

While some brain cells die directly because of lack of oxygen, others undergo programmed cell death, a normal developmental process where cells actively destroy their own DNA.

"The mystery was: how do the acidic conditions trigger DNA damage?" Ye says. "This was a very surprising result because previously we had no idea that AEP was involved in this process"......... Posted by: Daniel      Read more         Source

March 18, 2008, 9:12 PM CT

Does stress damage the brain?

Individuals who experience military combat obviously endure extreme stress, and this exposure leaves a number of diagnosed with the psychiatric condition of post-traumatic stress disorder, or PTSD. PTSD is linked to several abnormalities in brain structure and function. However, as researcher Roger Pitman explains, Eventhough it is tempting to conclude that these abnormalities were caused by the traumatic event, it is also possible that they were pre-existing risk factors that increased the risk of developing PTSD upon the traumatic events occurrence. Drs. Kasai and Yamasue along with their colleagues sought to examine this association in a new study reported in the March 15th issue of Biological Psychiatry.

The authors measured the gray matter density of the brains of combat-exposed Vietnam veterans, some with and some without PTSD, and their combat-unexposed identical twins using a technology called magnetic resonance imaging (MRI). The detailed images provided by the MRI scans then allowed the researchers to compare specific brain regions of the siblings. They observed that the gray matter density of the pregenual anterior cingulate cortex, an area of the brain involved in emotional functioning, was reduced in veterans with PTSD, but not in their twins who had not experienced combat. As per Dr. Pitman, this finding supports the conclusion that the psychological stress resulting from the traumatic stressor may damage this brain region, with deleterious emotional consequences......... Posted by: JoAnn      Read more         Source

March 18, 2008, 8:38 PM CT

Risk of Alzheimer's disease in their lifetime

Scientists from Boston University School of Medicine (BUSM) have estimated that one in six women are at risk for developing Alzheimers disease (AD) in their lifetime, while the risk for men is one in ten. These findings were released recently by the Alzheimers Association in their publication 2008 Alzheimers Disease: Facts and Figures.

Stroke and dementia are the most widely feared age-related neurological diseases, and are also the only neurological disorders listed in the ten leading causes of disease burden.

The scientists followed 2,794 participants of the Framingham Heart Study for 29 years who were without dementia. They found 400 cases of dementia of all types and 292 cases of AD. They estimated the lifetime risk of any dementia at more than one in five for women, and one in seven for men.

The realization that the lifetime risk of stroke or dementia was more than one in three in both sexes, which is higher than the lifetime risk of coronary heart disease in women, is sobering, said lead author Sudha Seshadri, MD, an associate professor of neurology at BUSM and an investigator of the Framingham Heart Study.

As per the researchers, the greater lifetime expectancy for women translates into a greater lifetime risk of several diseases......... Posted by: Daniel      Read more         Source

March 18, 2008, 5:08 AM CT

Pycnogenol improves memory in elderly

New research accepted for publication in the Journal of Psychopharmacology, demonstrates Pycnogenol, (pic-noj-en-all), an antioxidant plant extract from the bark of the French maritime pine tree, improves the memory of senior citizens.

The study results revealed Pycnogenol improved both numerical working memory as well as spatial working memory using a computerized testing system. The research was presented last week at the Oxygen Club of California 2008 World Congress on Oxidants and Antioxidants in Biology in Santa Barbara, CA.

These results support research from a range of disciplines that suggest that antioxidants may have an effect in preserving or enhancing specific mental functions, said Dr. Con Stough, lead researcher of the study. Cognitive research in this area specifically indicates that the putative benefits linked to antioxidant supplementation are linked to memory.

The double-blind, placebo controlled, matched pairs study, which was held at the Centre for Neuropsychology at Swinburne University, Melbourne Australia, examined the effects of Pycnogenol on a range of cognitive and biochemical measures in 101 senior individuals aged 60-85 years old. The study also examined the oxidative stress hypothesis of ageing and neurological degeneration as it relates to normal changes in cognition in elderly individuals. Participant screening for the study included medical history and cognitive assessment. Participants consumed a daily dose of 150mg of Pycnogenol for a three-month therapy period and were assessed at baseline then at one, two and three months of the therapy. The control and Pycnogenol groups were matched by age, sex, BMI, micronutrient intake and intelligence. The cognitive tasks comprised measures of attention, working memory, episodic memory and psycho-motor performance......... Posted by: Daniel      Read more         Source

March 16, 2008, 9:56 PM CT

Meditation Impacts Blood Pressure

Transcendental Meditation is an effective therapy for controlling hypertension with the added benefit of bypassing possible side effects and hazards of anti-high blood pressure drugs, as per a new meta-analysis conducted at the University of Kentucky. The study appears in the recent issue of the American Journal of Hypertension.

The meta-analysis reviewed nine randomized, controlled trials using Transcendental Meditation as a primary intervention for hypertensive patients. The practice of Transcendental Meditation was linked to approximate reductions of 4.7 mm systolic blood pressure and 3.2 mm diastolic blood pressure.

The study's lead author, Dr. James W. Anderson, professor of medicine at the University of Kentucky College of Medicine, said that blood pressure reductions of this magnitude would be expected to be accompanied by significant reductions in risk for atherosclerotic cardiovascular disease-without drug side effects. Anderson's most recent findings reinforce an earlier study that found Transcendental Meditation produces a statistically significant reduction in hypertension that was not found with other forms of relaxation, meditation, biofeedback or stress management.

"Adding Transcendental Medication is about equivalent to adding a second antihigh blood pressure agent to one's current regimen only safer and less troublesome," Anderson said......... Posted by: Daniel      Read more         Source

March 16, 2008, 9:39 PM CT

Researchers use light to detect Alzheimer's

A team of scientists in Bedford, Mass. has developed a way of examining brain tissue with near-infrared light to detect signs of Alzheimer's disease.

In the March 15 issue of the journal Optics Letters, published by the Optical Society of America, the team describes how they used optical technology to examine tissue samples taken from different autopsies and correctly identified which samples came from people who had Alzheimer's disease. Alzheimers currently afflicts some 4.5 million Americans and is the most common cause of dementia among older people in the United States.

"We're primarily interested in finding a way of diagnosing and monitoring Alzheimer's disease during life," says U.S. Department of Veterans Affairs Research Scientist Eugene Hanlon. "We think this technique has a lot of potential for detecting the disease early on".

The new technique developed by Hanlon and his collaborators at Harvard Medical School/Beth Israel Deaconess Medical Center and Boston University can detect alterations to the optical properties of the brain that occur as the tissue undergoes microscopic changes due to Alzheimer'ssometimes far in advance of clinical symptoms. The technique is now being tested for its effectiveness at diagnosing Alzheimer's disease in living people......... Posted by: Daniel      Read more         Source

March 16, 2008, 9:24 PM CT

Second depth-perception method in brain

Its common knowledge that humans and other animals are able to visually judge depth because we have two eyes and the brain compares the images from each. But we can also judge depth with only one eye, and researchers have been searching for how the brain accomplishes that feat.

Now, a team led by a scientist at the University of Rochester believes it has discovered the answer in a small part of the brain that processes both the image from a single eye and also with the motion of our bodies.

The team of researchers, led by Greg DeAngelis, professor in the Department of Brain and Cognitive Sciences at the University of Rochester, has published the findings in the March 20 online issue of the journal Nature.

It looks as though in this area of the brain, the neurons are combining visual cues and non-visual cues to come up with a unique way to determine depth, says DeAngelis.

DeAngelis says that means the brain uses a whole array of methods to gauge depth. In addition to two-eyed binocular disparity, the brain has neurons that specifically measure our motion, perspective, and how objects pass in front of or behind each other to create an approximation of the three-dimensional world in our minds.

The scientists say the findings may help instruct children who were born with misalignment of the eyes to restore more normal functions of binocular vision in the brain. The discovery could also help construct more compelling virtual reality environments someday, says DeAngelis, since we have to know exactly how our brains construct three-dimensional perception to make virtual reality as convincing as possible......... Posted by: Daniel      Read more         Source

March 13, 2008, 8:48 PM CT

Memory on Trial

The U.S. legal system has long assumed that all testimony is not equally credible, that some witnesses are more reliable than others. In tough cases with child witnesses, it assumes adult witnesses to be more reliable. But what if the legal system had it wrong?

Scientists Valerie Reyna, human development professor, and Chuck Brainerd, human development and law school professor--both from Cornell University--argue that like the two-headed Roman god Janus, memory is of two minds--that is, memories are captured and recorded separately and differently in two distinct parts of the mind.

They say children depend more heavily on a part of the mind that records, "what actually happened," while adults depend more on another part of the mind that records, "the meaning of what happened." As a result, they say, adults are more susceptible to false memories, which can be extremely problematic in court cases.

Reyna's and Brainerd's research, funded by the National Science Foundation, Arlington, Va., sparked more than 30 follow-up memory studies, a number of of them also funded by NSF. The scientists review the follow-on studies in an upcoming issue of Psychological Bulletin.

Tis research shows that meaning-based memories are largely responsible for false memories, particularly in adult witnesses. Because the ability to extract meaning from experience develops slowly, children are less likely to produce these false memories than adults, and are more likely to give accurate testimony when properly questioned......... Posted by: JoAnn      Read more         Source

March 13, 2008, 8:23 PM CT

Pain Receptor in Brain and Memory

Researchers have long known that the nervous system receptor known as TRPV1 can affect sensations of pain in the body. Now a group of Brown University researchers has observed that these receptors - a darling of drug developers - also may play a role in learning and memory in the brain.

In surprising new research, reported in the journal Neuron, Julie Kauer and her team show that activation of TPRV1 receptors can trigger long-term depression, a phenomenon that creates lasting changes in the connections between neurons. These changes in the brain - and the related process of neural reorganization known as long-term potentiation - are thought to bethe cellular basis for memory making.

"We've known that TRPV1 receptors are in the brain, but this is some of the first evidence of what they actually do there," Kauer said. "And the functional role we uncovered is unexpected. No one has previously linked these pain receptors to a cellular mechanism underlying memory. So we may have found a whole new player in brain plasticity".

The study findings have implications for drug development, Kauer said.

The research points out potentially effective new targets for drugs that could prevent memory loss or could possibly treat neural disorders such as epilepsy, Kauer said. The other implication may be cautionary. Drug makers already sell drugs - such as the weight-loss pill rimonabant, which is sold in Europe under the name Acomplia - that can block TRPV1 receptors. Other drugs aimed at reducing pain and inflammation by blocking or activating TRPV1 receptors are in the research pipeline. But drugs that bind to TRPV1 receptors in the central nervous system are likely to influence more than just pain-related functions, Kauer said......... Posted by: Daniel      Read more         Source

March 12, 2008, 9:31 PM CT

Paradoxical Alzheimer's finding linking memory loss

Do you remember the seventh song that played on your radio on the way to work yesterday? Most of us dont, thanks to a normal forgetting process that is constantly cleaning house culling inconsequential information from our brains. Scientists at the Buck Institute now think that this normal memory loss is hyper-activated in Alzheimers disease (AD) and that this effect is key to the profound memory loss linked to the incurable neurodegenerative disorder.

Last year, this same group of scientists observed that they could completely prevent Alzheimers disease in mice genetically engineered with a human Alzheimers geneMouzheimersby blocking a single site of cleavage of one molecule, called APP for amyloid precursor protein. Normally, this site on APP is attacked by molecular scissors called caspases, but blocking that process prevented the disease. Now they have studied human brain tissue and observed that, just as expected, patients suffering from AD clearly show more of this cleavage process than people of the same age who do not have the disease. However, when they extended their studies to much younger people without Alzheimers disease, they were astonished to find an apparent paradox: these younger people displayed as much as ten times the amount of the same cleavage event as the AD patients. The scientists now believe they know why......... Posted by: Daniel      Read more         Source

March 12, 2008, 9:29 PM CT

Ibuprofen Works Against Aspirin

Stroke patients who use ibuprofen for arthritis pain or other conditions while taking aspirin to reduce the risk of a second stroke undermine aspirin's ability to act as an anti-platelet agent, scientists at the University at Buffalo have shown.

In a cohort of patients seen by physicians at two offices of the Dent Neurologic Institute, 28 patients were identified as taking both aspirin and ibuprofen (a nonsteroidal anti-inflammatory drug, or NSAID) daily and all were found to have no anti-platelet effect from their daily aspirin.

Thirteen of these patients were being seen because they had a second stroke/TIA while taking aspirin and a NSAID, and were platelet non-responsive to aspirin (aspirin resistant) at the time of that stroke.

The scientists observed that when 18 of the 28 patients returned for a second neurological visit after discontinuing NSAID use and were tested again, all had regained their aspirin sensitivity and its ability to prevent blood platelets from aggregating and blocking arteries.

The study is the first to show the clinical consequences of the aspirin/NSAID interaction in patients being treated for prevention of a second stroke, and presents a possible explanation of the mechanism of action.

The Food and Drug Administration currently warns that ibuprofen might make aspirin less effective, but states that the clinical implications of the interaction have not been reviewed......... Posted by: Daniel      Read more         Source

March 11, 2008, 7:51 PM CT

New nerve cells originate from neural stem cells

Most cells in the human brain are not nerve cells, but supporting cells (glial cells). They serve as a framework for nerve cells and play an important role in the wound reaction that occurs with injuries to the brain. However, what these reactive glial cells in the brains of mice and men originate from, and which cells they evolve into was hitherto unknown.

Now, the study group of Prof. Dr. Magdalena Gtz is able to show that after injury, these reactive glial cells in the brains of mice restart their cell division. They then become stem cells from which nerve cells can form yet again under favourable cell culture conditions.

With this came the ground-breaking proof that, in an injured region of the brain, adult neural stem cells exist that could later serve as a source of new nerve cells.

In her study group, the stem cell expert, Magdalena Gtz, examines the molecular bases of cerebral development, in particular in the cerebral cortex. Gtz proved in earlier investigations that glial brain cells can act as stem cells, and nerve cells emerge from glial cells. She also pointed out which factors play a role in the cross-over from glial to neural cells. Now, thanks to these results, the distant goal of being able to use the processes therapeutically is getting a little closer stresses Gtz......... Posted by: Daniel      Read more         Source

March 5, 2008, 9:28 PM CT

Earlier, More Accurate Diagnosis of Alzheimer's Disease

Scientists involved in a large, multi-institutional study using positron emission tomography (PET) imaging with the radiotracer fluorodeoxyglucose (FDG) were able to classify different types of dementia with very high rates of success, raising hopes that dementia diagnoses may one day be made at earlier stages.

"Previously, researchers have been able to look only at the surface of the brain to differentiate various types of dementia," said Lisa Mosconi, Ph.D., assistant professor of psychiatry at the New York University School of Medicine. "With FDG PET, we were able to develop standardized disease-specific patterns from which we could correctly classify dementia more than 94 percent of the time."

The study, which was published in the recent issue of the Journal of Nuclear Medicine, measured the cerebral metabolic rate of glucose (CMRglc)-the amount of sugar the brain uses to fuel its activities-in various areas of the organ. A decrease in this rate is indicative of a loss of nerve cells and of dysfunction linked to dementia. Because FDG behaves like glucose when injected into the body, its location in the PET scans pinpointed the specific area where glucose utilization had fallen below normal levels as in comparison to an age-appropriate control group.

"Each type of dementia examined-Alzheimer's disease (AD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB)-affects a different area of the brain. Based on where in the brain this decrease occurred, we were able to determine which type of dementia a patient had," Mosconi explained......... Posted by: Daniel      Read more         Source

March 4, 2008, 4:25 PM CT

Links Betweenarts Education And Cognitive Development

Learning, Arts, and the Brain, a study three years in the making, is the result of research by cognitive neuroresearchers from seven leading universities across the United States. In the Dana Consortium study, released recently at a news conference at the Dana Foundation's Washington, DC headquarters, scientists grappled with a fundamental question: Are smart people drawn to the arts or does arts training make people smarter?

For the first time, coordinated, multi-university scientific research brings us closer to answering that question. Learning, Arts, and the Brain advances our understanding of the effects of music, dance, and drama education on other types of learning. Children motivated in the arts develop attention skills and strategies for memory retrieval that also apply to other subject areas.

The research was led by Dr. Michael S. Gazzaniga of the University of California at Santa Barbara. "A life-affirming dimension is opening up in neuroscience," said Dr. Gazzaniga, "to discover how the performance and appreciation of the arts enlarge cognitive capacities will be a long step forward in learning how better to learn and more enjoyably and productively to live. The consortium's new findings and conceptual advances have clarified what now needs to be done"......... Posted by: Daniel      Read more         Source

February 25, 2008, 8:58 PM CT

Many Stroke, Heart Attack Patients May Not Benefit from Aspirin

Up to 20 percent of patients taking aspirin to lower the risk of suffering a second cerebrovascular event do not have an antiplatelet response from aspirin, the effect thought to produce the protective effect, scientists at the University at Buffalo have shown.

"Millions of people use low-dose aspirin either for prevention of a second stroke, second heart attack or second episode of peripheral artery disease," said Francis M. Gengo, Pharm.D., lead researcher on the study.

Gengo is professor of neurology in the UB School of Medicine and Biomedical Sciences and professor of pharmacy practice in the UB School of Pharmacy and Pharmaceutical Sciences.

"In those three indications, it's crystal clear that aspirin reduces the risk of a second heart attack or stroke in most patients. But we have known for years that in some stroke and heart attack patients, aspirin has no preventive effect".

With no definitive data on the frequency of this condition, known as aspirin resistance, physicians were left with a best guess of between 5 and 50 percent, said Gengo.

UB scientists now have confirmed the 20 percent figure through a strictly controlled study conducted over 29 months in 653 consecutive stroke patients seen at Dent Neurologic Institute offices in the Buffalo suburbs Amherst and Orchard Park......... Posted by: Daniel      Read more         Source

February 14, 2008, 10:09 PM CT

Physicians Pinpoint Cause Of Children's Seizures

It was no way for an 11-year-old to live. For a month the boy had endured daily episodes of uncontrollable jerking and foaming at the mouth, and his physicians at Lucile Packard Children's Hospital were concerned that the boy had epilepsy. Before starting the boy on a lifetime of anti-seizure medications, though, they turned to an unconventional diagnostic tool: hypnosis.

"Children are highly suggestible and they have great imaginations," said Packard Children's child psychiatry expert Richard Shaw, MD. "We've observed that if we suggest that they are going to have one of their events while they are in a hypnotic trance, they will commonly have one".

But wait. Aren't physicians supposed to try to STOP seizures rather than searching for new ways to cause them? In a word, yes. But in order to treat seizures effectively, doctors must learn which parts of the brain are causing the trouble. A number of children who seem to be having epileptic seizures are actually having an involuntary physical reaction to psychological stress in their lives. These events require a vastly different therapy than do true epileptic seizures.

The only way to pinpoint the true cause is to monitor the child's brain activity during an event. Connecting a panel of electrodes to a child's scalp is relatively easy and painless. Conducting a "seizure watch" of indefinite length is another matter......... Posted by: JoAnn      Read more         Source

February 10, 2008, 10:04 PM CT

Moss protein plays role in Alzheimer's Disease

Preventing Alzheimer's disease is a goal of Raphael Kopan, Ph.D., professor of molecular biology and pharmacology at the Washington University School of Medicine. The moss plant Physcomitrella patens studied in the laboratory of Ralph S. Quatrano, Ph.D., the Spencer T. Olin Professor and chair of the biology department on WUSTL's Danforth Campus, might inch Kopan toward that goal. Here's how.

The gene presenilin (PS) in mammals provides the catalytic activity for an enzyme called gamma secretase, which cleaves, or cuts, important proteins Notch, Erb4 and the amyloid precursor protein (APP), all key components of communication channels that cells use to arbitrate functions during development. There are two mammalian genes that occur in mammals for which mutations cause an earlier onset of Alzheimer's. One is APP, where a fragment of the protein accumulates in amyloid plaques linked to the disease. Another common site for mutations is found in PS proteins. The enzyme gamma secretase contains PS and works to dispose of proteins stuck in the cellular membrane.

This enzyme, with PS at its core, mediates two cellular decisions. One is to cut APP and, as a byproduct, generate the bad peptide linked to Alzheimer's; the other is to cut the Notch protein in response to specific stimuli. Notch is then free to enter the nucleus of cells where it partakes in regulating normal gene expression. Without Notch activity, a mammal has no chance of living......... Posted by: Daniel      Read more         Source