Archives for March 2010

Where You Live Matters to Your Health

March 18, 2010 | by

The County Health Rankings — the first set of reports to rank the overall health of every county in all 50 states — were released recently by the University of Wisconsin’s Population Health Institute and the Robert Wood Johnson Foundation. The 50 state reports, available on www.countyhealthrankings.org, enables consumers, public health and community leaders, policy-makers and others to see how healthy their county is, compare it with others within their state and find ways to improve the health of their community.

County Health Rankings

The County Health Rankings

The County Health Rankings identify the healthiest and least healthy counties within every state in the nation. Health outcomes in the County Health Rankings represent how healthy a county is. Two types of health outcomes are measured: how long people live (mortality) and how healthy people feel while alive (morbidity).

Impulsive-Antisocial Personality Traits Linked to a Hypersensitive Brain Reward System

March 15, 2010 | by

Normal individuals who scored high on a measure of impulsive/antisocial traits display a hypersensitive brain reward system, according to a brain imaging study by researchers at Vanderbilt University. The findings provide the first evidence of differences in the brain’s reward system that may underlie vulnerability to what’s typically referred to as psychopathy.

The study in the current issue of the journal Nature Neuroscience was funded by the National Institute on Drug Abuse (NIDA), a component of the National Institutes of Health.

Psychopathy is a personality disorder characterized by a combination of superficial charm, manipulative and antisocial behavior, sensation-seeking and impulsivity, blunted empathy and punishment sensitivity, and shallow emotional experiences. Psychopathy is a particularly robust predictor of criminal behavior and recidivism.

Since psychopathic individuals are at increased risk for developing substance use problems, the Vanderbilt team decided to investigate possible links between the brain’s reward system (activated by abused substances and natural reward), and a behavioral trait (impulsive/antisociality) characteristic of psychopathy. Researchers used two different technologies to measure the brain’s reward response.

Health Highlights – March 11th, 2010

March 11, 2010 | by

Health Highlights is a biweekly summary of particularly interesting articles from credible sources of health and medical information that we follow & read. For a complete list of recommeded sources, see our links page.

Health Highlights

New Approach to Immune Cell Analysis Seen as First Step to Better Distinguish Health and Disease

March 9, 2010 | by

Investigators have developed a new mathematical approach to analyze molecular data derived from complex mixtures of immune cells. This approach, when combined with well-established techniques, readily identifies changes in small samples of human whole blood, and has the potential to distinguish between health and disease states.

Led by Mark Davis, Ph.D., and Atul Butte, M.D., Ph.D., of Stanford University, Calif., the team of investigators received support from the National Institute of Allergy and Infectious Diseases (NIAID), as well as the National Heart, Lung, and Blood Institute and the National Cancer Institute, all part of the National Institutes of Health. Details about their work appear online at Nature Methods.

“Defining the status of the human immune system in health and disease is a major goal of human immunology research,” says NIAID Director Anthony S. Fauci, M.D. “A method allowing clinicians to accurately and quickly characterize the many different immune cells in human blood would be a valuable research and diagnostic tool.”

Over the past 15 years, the technology for gene expression microarrays, which allow investigators to identify and measure relative amounts of many different genes in parallel, has advanced tremendously. Today researchers can measure nearly every gene in the human genome using very small amounts of blood. However, blood contains numerous types of immune cells, such as lymphocytes, basophils and monocytes, and when microarray analysis is performed on this mixture, the interpretation of the results becomes problematic.

Scientists Find New Form of Prion Disease that Damages Brain Arteries

March 9, 2010 | by

National Institutes of Health (NIH) scientists investigating how prion diseases destroy the brain have observed a new form of the disease in mice that does not cause the sponge-like brain deterioration typically seen in prion diseases. Instead, it resembles a form of human Alzheimer’s disease, cerebral amyloid angiopathy, that damages brain arteries.

NIH Newsbot Note: Cerebral amyloid angiopathy (CAA) is a neurological condition in which amyloid protein builds up on the walls of the arteries in the brain. The condition increases an individual’s risk of stroke, brain hemorrhage or dementia. There is no known effective treatment.
Cerebral amyloid angiopathy

The study results, reported by NIH scientists at the National Institute of Allergy and Infectious Diseases (NIAID), are similar to findings from two newly reported human cases of the prion disease Gerstmann-Straussler-Scheinker syndrome (GSS). This finding represents a new mechanism of prion disease brain damage, according to study author Bruce Chesebro, M.D., chief of the Laboratory of Persistent Viral Diseases at NIAID’s Rocky Mountain Laboratories.

Prion diseases, also known as transmissible spongiform encephalopathies, primarily damage the brain. Prion diseases include mad cow disease or bovine spongiform encephalopathy in cattle; scrapie in sheep; sporadic Creutzfeldt-Jakob disease (CJD), variant CJD and GSS in humans; and chronic wasting disease in deer, elk and moose.

The role of a specific cell anchor for prion protein is at the crux of the NIAID study. Normal prion protein uses a specific molecule, glycophosphoinositol (GPI), to fasten to host cells in the brain and other organs. In their study, the NIAID scientists genetically removed the GPI anchor from study mice, preventing the prion protein from fastening to cells and thereby enabling it to diffuse freely in the fluid outside the cells.

The scientists then exposed those mice to infectious scrapie and observed them for up to 500 days to see if they became sick. The researchers documented signs typical of prion disease including weight loss, lack of grooming, gait abnormalities and inactivity. But when they examined the brain tissue, they did not observe the sponge-like holes in and around nerve cells typical of prion disease. Instead, the brains contained large accumulations of prion protein plaques trapped outside blood vessels in a disease process known as cerebral amyloid angiopathy, which damages arteries, veins and capillaries in the brain. In addition, the normal pathway by which fluid drains from the brain appeared to be blocked.

Their study, Dr. Chesebro says, indicates that prion diseases can be divided into two groups:

  • those with plaques that destroy brain blood vessels
  • those without plaques that lead to the sponge-like damage to nerve cells

Dr. Chesebro says the presence or absence of the prion protein anchor appears to determine which form of disease develops.

The new mouse model used in the study and the two new human GSS cases, which also lack the usual prion protein cell anchor, are the first to show that in prion diseases, the plaque-associated damage to blood vessels can occur without the sponge-like damage to the brain. If scientists can find an inhibitor for the new form of prion disease, they might be able to use the same inhibitor to treat similar types of damage in Alzheimer’s disease, Dr. Chesebro says.

Source: NIH News