Possible key to Lyme disease. A toxin that may be responsible for many of the symptoms associated with Lyme disease has been identified by Boston University Medical Center (BUMC) researchers. The study results were presented November 13 at the annual meeting of the Infectious Diseases Society of America.
Dr. Sam Donta, professor of medicine and director of the BUMC Lyme Disease Center, and his research team recently identified a substance produced by the Lyme disease bacterium (B. burgdorferi) that appears to kill nervous system cells. "If we can learn precisely how the toxin works, we may be able to revolutionize the diagnosis and treatment of this debilitating disease," he says.
Lyme disease was first identified in 1975 and has been discovered in every region of the United States as well as in Europe, Asia, Africa, and Australia. The bacterium is transmitted to humans by the bite of an infected tick.
Members of the research team don't completely understand how the toxin acts, but believe that it may work similarly to botulism, tetanus, and cholera toxins. "Lyme disease patients suffer from many symptoms, and if this toxin is at the root of those, it may be possible to make a vaccine, or antitoxin, like the ones available for botulism and tetanus," says Donta.
It may also be possible to develop a better test for the disease using the newly identified toxin. "Antibodies to the toxin may appear in the blood, urine, or spinal fluid," he explains. Studies are already under way to identify the specific target of the toxin and its precise role in Lyme disease.
The research was conducted with the help of a grant from the Thaler Family and Pasiss Family Foundation.
Hard habits to break. Cocaine addiction, which has a relapse rate of around 80 percent, is notoriously difficult to treat. In a current study, CAS Professor of Psychology Kathleen Kantak is exploring the cognitive aspects of addiction -- learned behavior and memory -- to discover more effective ways to treat the problem.
"The pharmacological therapies available right now just don't work very well," she says. "Within a few years we hope to lay the groundwork for new ways of treating drug addiction that include cognitive and behavioral therapies."
According to Kantak, recovering drug addicts experience cravings and may relapse when they are exposed to cues that remind them of previous drug use, such as a bar they used to frequent or people they knew when using cocaine.
In a recent study, researchers did PET scans on people who had been given cues associated with their cocaine use that elicited cravings for the drug. "The PET scans showed activity in areas of the brain associated with cognitive and learning processes," she says, "which are different areas than the part of the brain associated with the rewarding effects of cocaine use."
Kantak and colleague Howard Eichenbaum, CAS professor of psychology, are now testing this theory on laboratory rats to discover which memory systems are most important to the animals' cognitive behavior regarding cocaine addiction. In the second part of the study, they'll try to determine how persistent, self-administered use of cocaine and morphine affects cognitive processes. "There aren't any studies where the users -- as opposed to the experimenters -- administer the drugs," she says. "There might be unique ways in which taking the drug yourself affects cognition."
Briefs" is written by Joan Schwartz in the Office of the Provost. To read
more about BU research, visit http://www.bu.edu/research.