SCIENCE IN THE NEWS - Diabetes(在线收听

SCIENCE IN THE NEWS - December 3, 2002: Diabetes

By Oliver Chanler


VOICE ONE:
This is Steve Ember.
VOICE TWO:
And this is Bob Doughty with Science in the News, a VOA Special English program about recent developments


in science. Today, we tell about the disease diabetes.
((THEME)
)
VOICE ONE:


The World Health Organization estimates that as many as one-hundred-twentymillion people have the disease diabetes. Diabetes is the name for several diseases
with one thing in common: there is too much glucose, or sugar, in the blood. The
disease develops when the body does not produce enough insulin or produces no
insulin. Or the disease develops when the body cannot use insulin.

Insulin is a hormone that is necessary to change sugar, carbohydrates and other food
into energy. In healthy people, the body changes food into a sugar, called glucose.
Glucose is the source of fuel for the body. When food is changed into glucose, it
enters the bloodstream and is taken to all parts of the body to feed muscles, organs,
and tissue.

VOICE TWO:

When the body senses that there is too much glucose in the blood, it sends a signal to the pancreas. The pancreas
is the organ that produces insulin. The pancreas sends insulin into the bloodstream. The insulin lowers the level
of blood sugar by letting it enter cells. Insulin helps muscles, organs and tissues take glucose and change it into
energy.

That is how the body operates normally, in most people. Diabetes is present when too much glucose remains in
the bloodstream and does not enter cells. If the amount of glucose in the blood remains too high, the body begins
showing signs of diabetes. Over time, the disease can cause blindness, kidney disease, and nerve damage.

High glucose levels in the blood also can lead to strokes and heart disease. Blood circulation also is affected,
especially in the legs. Often, victims of diabetes must have a foot or even a leg removed because of blood
circulation problems linked to the disease.

((MUSIC BRIDGE))

VOICE ONE:

There are two main kinds of diabetes, Type One and Type Two. Between five and ten percent of those suffering
from diabetes have Type One. It usually begins before the age of thirty in people who are thin.

It is most commonly found in children under the age of sixteen. It is caused by the body’s defense system. The
bodies of Type One diabetes victims produce a substance that attacks and kills some cells in the pancreas,
blocking the production of insulin. These cells are called islet (EYE-lit) cells. Scientists are not sure why this
happens. They believe there may be a number of causes.

They include viruses, the presence of insect-killing pesticides in the environment or molecules known as free



radicals. Free radicals are produced as part of normal chemical processes in the body. In people with diabetes, too
many of these free radicals are present in the body. Scientists are not sure which of these causes is the most
important to the development of Type One diabetes.

VOICE TWO:

People suffering from Type One diabetes must carefully control their diets. And they must exercise often. People
with this kind of diabetes almost always require insulin injections. Patients must always know their blood sugar
levels. When the level of glucose in the blood is too high, they must inject insulin into their bodies to reduce the
amount of glucose.

The patients must inject insulin every day, often several times a day. In most developed countries, insulin is easy
to get and does not cost much money. However, doctors believe that these injections can cause long-term
problems. They believe that the injections cause levels of glucose to change often.

Scientists believe that many quick changes in glucose levels can, over time, result in damage to the body. This
damage can be blindness, kidney failure, heart disease, or poor blood flow in the body.

VOICE ONE:

Type One diabetes also is known as juvenile onset diabetes, because it usually starts in children or young people.
Scientists believe it is the form of the disease that they will most likely be able to cure some day. Among the
treatments being studied is a vaccine to prevent the disease. A vaccine is injected into the body or taken by mouth
in the form of a pill.

Another possible treatment for Type One diabetes is placing new islet cells into the pancreas to help it make
insulin. Doctors have been transplanting islet cells into diabetes patients for several years. However, these
healthy islet cells have failed to permanently replace the need for insulin injections.

Scientists also are studying special cells called stem cells to treat the disease. Stem cells develop into all the
different kinds of cells in the body. Scientists believe that stem cells from unborn babies could be used to treat
diabetes and other diseases. However, it would be a long time before such treatment is possible.

VOICE TWO:

While some scientists continue to seek ways to cure Type One diabetes, others are searching for easier ways to
get insulin into the body. New devices are being developed that could replace injections. One device being tested
is an inhaler.

This device would permit patients to breathe insulin into their bodies. The insulin is in the form of a powder, like
dust. When the insulin reaches the lungs, it quickly moves into the bloodstream to reduce glucose levels.

((MUSIC BRIDGE))

VOICE ONE:

Type Two diabetes generally is found in people more than forty years old. Most of these people are too fat. Their
bodies can not produce enough insulin to reduce the levels of glucose in their blood. Or, their bodies do not react
correctly to the action of insulin.

Type Two diabetes is more complex than Type One. Experts say Type Two diabetes is really a group of diseases,
with many possible causes. Scientists see little hope in developing a cure for this kind of diabetes. Instead, they
are searching for better ways to control it.

Many people suffering from the disease can control it with exercise and by carefully controlling their diet. Also,
many of them do not need to inject insulin into their bodies. Type Two diabetes is sometimes called non-insulin
dependent. Still, patients often need drugs to treat the disease.

VOICE TWO:


There are a number of drugs that can be used. However, many of them can cause other problems. One of the
drugs is called sulfonylurea. It has been used for many years to help the pancreas make more insulin. But after
several years, the drug loses its effects on the pancreas. Also, it can cause patients to gain weight.

The drug metformin appears to be more effective. It lowers the amounts of glucose in the blood. It does this by
helping the body make better use of its own natural insulin. It does not cause weight gain. However, metformin
can be dangerous for people with damaged kidneys. It should not be used by people who drink large amounts of
alcohol, or those with kidney, liver or heart problems.

VOICE ONE:

Genes seem to be more important in the development of Type Two diabetes than in Type One. About ninety
percent of those with Type Two diabetes have parents and ancestors who also had the disease. In recent years,
scientists have found several genes that may be linked to Type Two diabetes. Some of these genes also are linked
to extreme overweight, known as obesity.

About eighty to ninety percent of people with Type Two diabetes are obese. Often doctors do not discover that
patients have diabetes until one of the disease’s serious results is found. For example, a doctor examines a
patient suffering several health problems.

The doctor carries out tests and finds the problems are the results of poor kidney performance. Tests then show
the patient is suffering from diabetes, which can cause kidney problems and even failure.

VOICE TWO:

Although great progress has been made in the treatment of diabetes, it is still widespread and threatens the health
of millions of people. Scientists hope that their research will lead to a cure for Type One diabetes. And they hope
they can find new ways to improve treatment of Type Two diabetes. In future programs we will discuss new
developments in diabetes research as they are reported.

((THEME))

VOICE ONE:

This Science in the News program was written by Oliver Chanler. This is Steve Ember.

VOICE TWO:

And this is Bob Doughty. Join us again next week for more news about science in Special English on the Voice
of America.


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