2004-2-3
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.