HEALTH REPORT - New Method to Find Alzheimer's Disease
By Jerilyn Watson
This is the VOA Special English Health Report.
Alzheimer's disease usually appears late in life. In the United States alone, experts say about four million people have this brain disorder. Over time, it robs people of their memory and ability to think. There are no cures.
Until now, Alzheimer's could be confirmed only by examining brain tissue after death or by taking brain tissue from a living patient. Now, a new test offers hope that Alzheimer's may be found earlier.
Experts currently give written and spoken tests to help decide if a person has the disease. They also use a process called magnetic resonance imaging to see the brain changes that may mean Alzheimer's.
Many patients already have been seriously affected by the time the disease shows up on these M-R-I's. Most of the materials believed linked to the disease are present on the image. They are called protein clumps.
But the new test makes it possible to see the protein clumps before they could be found by M-R-I. The new test might identify the disease before a person shows signs of Alzheimer's. Treatment could begin earlier. Doctors could see if the treatment is helping. New or improved drugs may be developed.
William Klunk of the University of Pittsburgh School of Medicine in Pennsylvania helped invent the test. It calls for patients to receive a small amount of a radioactive molecule called Pittsburgh Compound B. It is administered through the blood.
Doctor Klunk says it connects itself to proteins called amyloid plaques. These plaques exist in the brains of Alzheimer's patients. Doctors can see them with an examination called a PET scan. Proteins affected by Alzheimer's show as yellow and red.
For years, Doctor Klunk and his team searched for a substance that could connect with the amyloid. Finally they found a material that can reach the brain through the blood. This Pittsburgh Compound B can color the amyloid.
The finding led to a test of sixteen suspected Alzheimer's patients. The researchers say the test found amyloid in those patients. It also found small amounts in one of nine healthy people tested for comparison. Testing on more people is needed. The United States Food and Drug Administration currently is considering approval of the process.
This VOA Special English Health Report was written by Jerilyn Watson.
资料更新时间: 2004-2-18 18:42:23