Brain
Parkinson’s disease research uncovers social barrier
People with Parkinson’s disease suffer social difficulties simply because of the way they talk, a McGill University researcher has discovered. Marc Pell, at McGill’s School of Communication Sciences and Disorders, has learned that many people develop negative impressions about individuals with Parkinson’s disease, based solely on how they communicate. These perceptions limit opportunities for social interaction and full participation in society for those with the disease, reducing their quality of life. Pell’s research offers the public a better understanding of the difficulties these patients face – as well as an opportunity to promote greater inclusiveness.
The research was conducted in collaboration with Abhishek Jaywant, a research trainee in McGill’s Neuropragmatics and Emotion Lab, and with financial support from the Canadian Institutes of Health Research and the Fonds de la recherche en santé du Québec.
Aging adults both with and without Parkinson’s were recorded as they described visual scenes. Their voices were then played to listeners who were unaware of the speaker’s health status. Those with Parkinson’s disease were perceived as less interested, less involved, less happy and less friendly than aging speakers without the disease. Negative impressions of their personality were specifically related to changes in the speaking voices caused by the disease, not the ability to describe the scenes.
Genetic Risk Factor Identified for Parkinson’s Disease: Gene Variant Influences Vitamin B6 Met
Munich, January 11, 2010. An international team of doctors and human geneticists has identified a new genetic risk factor for Parkinson’s disease. The institutions involved in the study were the Institute of Human Genetics of Helmholtz Zentrum München and Technische Universität München, the Neurological Clinic of Ludwig-Maximilians-Universität Munich (LMU) and the Mitochondrial Research Group of Newcastle University, Newcastle upon Tyne, UK.
“Our study reveals the interaction of genetic and environmental factors such as dietary habits in the pathogenesis of Parkinson’s disease,” explained Dr. Matthias Elstner of the Neurological Clinic of LMU and Helmholtz Zentrum München, lead author of the study. In addition, this genome-wide expression and association study confirms that vitamin B6 status and metabolism significantly influence both disease risk and therapy response (Annals of Neurology, January, 2010).
Scientists of the two Munich universities and Helmholtz Zentrum München investigated neurons in the brain to determine which genes modify their activity in Parkinson’s disease. Among other findings, the research group detected increased activity of the pyridoxal kinase gene.
Gene variant protects against Alzheimer’s
People with a gene linked to long life and good health are also less likely to develop Alzheimer’s disease, U.S. researchers said on Tuesday.
They said people with two copies of a certain version of the cholesteryl ester transfer protein or CETP gene had significantly slower memory declines compared with people who had different versions of the gene.
“We’ve known for a long time that genetic factors matter in Alzheimer’s disease,” said Dr. Richard Lipton of Albert Einstein College of Medicine at Yeshiva University in New York, whose study appears in the Journal of the American Medical Association.
Why some brains are more vulnerable to stress and resistant to antidepressants
A new study provides insight into the molecular characteristics that make a brain susceptible to anxiety and depression and less likely to respond to treatment with antidepressant medication. The research, published by Cell Press in the January 14th issue of the journal Neuron, may lead to more effective strategies for treating depression, a major health concern throughout the world.
Although brain mechanisms associated with depression and anxiety are not completely clear, recent research has implicated a combination of stressful life events and predisposing biological factors as playing a causal role in depressive disorders. The most popular antidepressant medications, such as the commonly prescribed selective serotonin reuptake inhibitors (SSRIs), increase serotonin levels in the brain.
“Unfortunately, more than half of all depressed patients fail to respond to their first drug treatment,” explains senior study author Dr. Rene Hen, from Columbia University. “The reasons for this treatment resistance remain enigmatic. Elucidating the exact nature of both the factors predisposing to depression and the mechanisms underlying treatment resistance remains an important and unmet need.”
New approach to fighting Alzheimer’s shows potential in clinical trial
In the early stages of Alzheimer’s disease, patients typically suffer a major loss of the brain connections necessary for memory and information processing. Now, a combination of nutrients that was developed at MIT has shown the potential to improve memory in Alzheimer’s patients by stimulating growth of new brain connections.
In a clinical trial of 225 Alzheimer’s patients, researchers found that a cocktail of three naturally occurring nutrients believed to promote growth of those connections, known as synapses, plus other ingredients (B vitamins, phosopholipids and antioxidants), improved verbal memory in patients with mild Alzheimer’s.
“If you can increase the number of synapses by enhancing their production, you might to some extent avoid that loss of cognitive ability,” says Richard Wurtman, the Cecil H. Green Distinguished Professor of Brain and Cognitive Sciences, who did the basic research that led to the new experimental treatment. He is an author of a paper describing the new results in the journal Alzheimer’s and Dementia.
Alzheimer’s protein may be early risk factor
Imaging tests may be able to detect the early signs of Alzheimer’s disease long before it begins to affect memory, a finding that may lead to earlier, more effective treatments, U.S. researchers said on Monday.
They said healthy people who have an abnormal buildup of a protein in the brain linked with Alzheimer’s disease have a higher risk of developing the disease.
“Our paper shows for the time that people who during life are known to have amyloid plaques in the brain - the plaques of Alzheimer’s disease - have a very high risk of developing dementia in just a few years,” said John Morris, director of Washington University in St. Louis, Missouri, whose study appears in the journal Archives of Neurology.
Surgery Not Linked to Memory Problems in Older Patients
For years, it has been widely assumed that older adults may experience memory loss and other cognitive problems following surgery. But a new study from researchers at Washington University School of Medicine in St. Louis questions those assumptions. In fact, the researchers were not able to detect any long-term cognitive declines attributable to surgery in a group of 575 patients they studied.
“There’s a perception that people go in for surgery, and they aren’t quite the same afterward,” says first author Michael S. Avidan, M.D. “The reports of cognitive deterioration have varied, but several studies have suggested it affects many elderly people. In my experience as an anesthesiologist, I’ve found this is a very common concern.”
But Avidan, associate professor of anesthesiology and surgery, and fellow investigator Alex S. Evers, M.D., the Henry E. Mallinckrodt Professor and head of the Department of Anesthesiology, questioned those conclusions.
‘Scaffolding’ Protein Changes in Heart Strengthen Link Between Alzheimer’s Disease
A team of U.S., Canadian and Italian scientists led by researchers at Johns Hopkins report evidence from studies in animals and humans supporting a link between Alzheimer’s disease and chronic heart failure, two of the 10 leading causes of death in the United States.
The international team of biochemists and cardiologists say they have identified three changes in the chemical make-up of a key structural protein, called desmin, in heart muscle cells in dogs. The changes led to the formation of debris-like protein clusters, or amyloid-like oligomers containing desmin, in heart muscle, similar to the amyloid plaques seen in the brain tissue of Alzheimer’s patients. The protein alterations, which were reversed by surgically repairing the heart, occurred at the onset of heart failure. Further experiments by the Hopkins scientists found the same chemical modifications to desmin in the heart muscle in four people already diagnosed with the disease.
Hybrid molecules show promise for exploring, treating Alzheimer’s
One of the many mysteries of Alzheimer’s disease is how protein-like snippets called amyloid-beta peptides, which clump together to form plaques in the brain, may cause cell death, leading to the disease’s devastating symptoms of memory loss and other mental difficulties.
In order to answer that key question and develop new approaches to preventing the damage, scientists must first understand how amyloid-beta forms the telltale clumps.
University of Michigan researchers have developed new molecular tools that can be used to investigate the process. The molecules also hold promise in Alzheimer’s disease treatment. The research, led by assistant professor Mi Hee Lim, was published online this week in the Journal of the American Chemical Society.
Though the exact mechanism for amyloid-beta clump formation isn’t known, scientists do know that copper and zinc ions are somehow involved, not only in the aggregation process, but apparently also in the resulting injury. Copper, in particular, has been implicated in generating reactive oxygen species, which can cause cell damage.
Diabetics with Alzheimer’s have slower memory loss
People who have both Alzheimer’s disease and diabetes have slower rates of memory loss than people who just have Alzheimer’s disease, French researchers said on Tuesday.
They studied 600 Alzheimer’s patients for four years and found those who had both Alzheimer’s and diabetes—about 10 percent of the total—scored far better on twice yearly memory and thinking tests than those with Alzheimer’s who did not have diabetes.
“This result was surprising,” said Dr. Caroline Sanz of the French National Institute for Health and Medical Research, whose study appears in the journal Neurology.
Treatment of severe burn injuries
Almost three quarters of patients with extensive burns die of the consequences of a severe infection. In the current edition of Deutsches Ärzteblatt International (Dtsch Arztebl Int 2009; 106[38]: 607-13), Timo A. Spanholtz of the Cologne-Merheim Burn Center and his coauthors discuss the acute therapy and follow-up care of burn disease.
Optimal treatment of severely burned patients necessitates collaboration between primary care physicians, emergency physicians and specialist departments for plastic surgery. During first aid from the emergency physician, the patient is removed from the danger zone and is administered adequate fluid, and drugs, over several intravenous accesses. Additional first aid measures include cooling and sterile covering of the burned skin.
The Central Office for Burn Injuries in Hamburg then organizes the necessary transfer to a specialist department.
Yale team finds mechanism that constructs key brain structure
Yale University researchers have found a molecular mechanism that allows the proper mixing of neurons during the formation of columns essential for the operation of the cerebral cortex, they report in the Sept. 16 online issue of the journal Nature.
Scientists have known for years that information processing in the cerebral cortex depends upon groupings of neurons that assemble in the shape of vertical columns. If the number and mix of neurons in the column are wrong, severe cognitive problems can result. For instance, malformations of these columns have been implicated in some forms of autism and mental retardation. Scientists, however, have not been able to find the molecular mechanism responsible for this intermixing.
In the Nature paper, a team led by Pasko Rakic, professor and chairman of the Department of Neurobiology and head of the Kavli Institute for Neuroscience, describes one of the molecular mechanisms essential to the organizations of these key structures.
Unhealthy habits alter thinking, memory skills
If you’re having trouble remembering where you left your keys or recalling a word, mull over the number of times and how many years you’ve continued unhealthy behaviors.
Previous research has linked declining thinking and memory skills with unhealthy behaviors such as smoking, abstaining completely from alcohol, not getting enough physical activity, and not eating enough fruits and vegetables daily.
In the current study, Dr. Severine Sabia and colleagues found the more each of the 5,123 adult participants reported these behaviors the greater their “risk of cognitive deficit,” Sabia told Reuters Health in an email.
New treatment option for ruptured brain aneurysms
Researchers in Finland have identified an effective new treatment option for patients who have suffered a ruptured brain aneurysm, a potentially life-threatening event. Results of the new study on stent-assisted coil embolization were published today in the online edition of Radiology.
An aneurysm is a bulge or sac that develops in a weak area of a cerebral artery wall. Subarachnoid hemorrhage occurs when an aneurysm ruptures, diverting oxygen-rich blood from vital areas to the space between the brain and the skull. The ruptured vessel can be repaired surgically or through a minimally invasive procedure called embolization, in which the sac is filled with metal coils in order to prevent repeat bleeding from the aneurysm and to restore normal blood flow in the artery.
“The treatment decision is complicated in cases of acutely ruptured aneurysms,” said the study’s lead author, Olli Tähtinen, M.D., assistant professor of radiology at Tampere University Hospital in Tampere, Finland.
Strong link found between concussions and brain tissue injury
Concussions, whether from an accident, sporting event, or combat, can lead to permanent loss of higher level mental processes. Scientists have debated for centuries whether concussions involve structural damage to brain tissue or whether physiological changes that merely impair the way brain cells function, explain this loss. Now, for the first time, researchers at Albert Einstein College of Medicine of Yeshiva University have linked areas of brain injury to specific altered mental processes caused by concussions.
The research, described in the August 26 edition of Radiology, provides compelling evidence that concussions involve brain damage. The findings suggest that diffusion tensor imaging (DTI), the brain scanning method used by the Einstein scientists, could help in diagnosing concussions and in assessing the effectiveness of treatments.
“DTI has been used to look at other brain disorders, but this is the first study to focus on concussions,” said Michael Lipton, M.D., Ph.D., associate director of the Gruss Magnetic Resonance Research Center (MRRC) and associate professor of radiology, of psychiatry and behavioral sciences, and of neuroscience at Einstein and lead author of the study. “It proved to be a powerful tool for detecting the subtle brain damage that we found to be associated with concussions.”
