New imaging method accurately detects stroke

Diffusion-weighted MR imaging is an accurate way to detect whether a patient has had a stroke–even 24 hours after the patient’s initial symptoms began, a new study shows. The study, the largest of its kind, found that diffusion-weighted MR imaging was about 90 percent accurate in diagnosing stroke, says Mark Mullins, MD, PhD, of Massachusetts General Hospital. Dr. Mullins was the lead author of the study. Diffusion-weighted MR imaging was 91% accurate if the test was done 0-6 hours after the patient first began having symptoms; accuracy was 89% at 6-12 hours, then 90% at 12-24 hours, says Dr. Mullins.

Study identifies changes in the eyes of Alzheimer's sufferers

A research team led by investigators from Massachusetts General Hospital (MGH) and Brigham and Women’s Hospital (BWH) has discovered that amyloid-beta (A-beta), the protein that forms plaques in the brains of people with Alzheimer’s disease, can also be detected in the lens of the human eye. The investigators were able to identify A-beta in lens samples from elderly individuals with and without the disorder; however, an unusual pattern of amyloid deposits was found only on the lenses of Alzheimer’s patients.

Minimally invasive treatment successfully destroys kidney tumors

A minimally invasive, experimental treatment is proving successful in removing small kidney tumors from appropriate patients, report researchers from Massachusetts General Hospital (MGH). In a study in the February 2003 issue of Radiology, the MGH team describes how a technique called radiofrequency ablation (RFA) destroyed all renal cell carcinoma (RCC) tumors less than 3 cm in size and some larger tumors, depending on their location. The most common form of kidney cancer, RCC will be diagnosed in almost 32,000 Americans this year and is most frequently treated with surgical removal through either an open or laparoscopic procedure.

Drug treatment for ADHD sharply cuts risk for future substance abuse

An analysis of all available studies that examine the possible impact of stimulant treatment for attention-deficit hyperactivity disorder (ADHD) on future substance abuse supports the safety of stimulant treatment. Using a statistical technique called meta-analysis, the researchers found that medication treatment for children with ADHD resulted in an almost two-fold reduction in the risk of future substance abuse. “We know that untreated individuals with ADHD are at a significantly increased risk for substance abuse. And we understand why parents often ask whether stimulant medications might lead to future substance abuse among their children,” says Timothy Wilens, MD, MGH director of Substance Abuse Services in Pediatric Psychopharmacology, the paper’s lead author. “Now we can reassure parents and other practitioners that treating ADHD actually protects children against alcohol and drug abuse as well as other future problems.”

Infection by closely related HIV strains possible

A report of an individual infected with a second strain of HIV despite effective drug treatment following the first infection has researchers concerned. “For the first time, we’ve shown it is possible for an individual to become infected with two closely related strains of HIV,” says Bruce D. Walker, M.D., a researcher at Massachusetts General Hospital and Harvard Medical School. The findings underscore the challenges vaccine developers face in creating a broadly effective vaccine against HIV. The first HIV vaccines may not prevent infection altogether, but rather may prevent HIV from causing disease by limiting the virus’ ability to reproduce, explains Dr. Walker. This case shows that a hypothetical vaccine against one strain of HIV may not necessarily protect the vaccinee against other, closely related strains.

Study Identifies Gene That Prevents Nerve Cell Death

Many neurological diseases occur when specific groups of neurons die because of nerve damage, toxins, inflammation, or other factors. A new study suggests that activity of a single gene can stop neurons from dying regardless of what triggers this process. The findings could lead to new ways of treating neurodegenerative diseases.

From the mouthes of Babe

This weekend I sank my teeth into some delicious beef ribs. But researchers at the Forsyth Institute say they’ve done one better ? they’ve sunk pork teeth into rat guts. The experiment involved taking seeded cells from immature teeth of six-month-old pigs and placing them in the intestines of rats (who no doubt were thrilled at the addition). Within 30 weeks, small tooth crowns made of enamel and dentin had formed. Within five years, the Forsythe team says, they hope to be able to harvest teeth of specific size and shape, and five years after that to regrow human teeth.

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