This is SCIENCE IN THE NEWS in VOA Special
English. I'm Bob Doughty.
I'm Barbara Klein. This week, we will
tell about a fat cell gene linked to colon cancer. We will also tell about new developments in
the fight against the disease tuberculosis.
And, we will tell about something new at America's Smithsonian
A new study has found that a fat cell gene may reduce
the risk of colon cancer in some people.
The study provides what scientists say is the first evidence of a
genetic link between a fat cell gene and colon cancer. The finding could lead to better tests for
the disease and measures to help prevent it.
evidence suggests a relationship between obesity, insulin resistance and colon
cancer risk. The scientists say what
they have found now is an area of a gene that is connected with the cancer
risk. They say this area is most likely
not the cause of the disease. But they
think it is where the connection comes from.
gene is involved in the formation of a hormone called adiponectin. Some people have higher levels of this
hormone in their blood. Others have
lower levels. Higher levels have been
linked with lower rates of obesity and insulin resistance. Lower levels have been linked with higher
Journal of the American Medical Association published the findings last
Colon cancer is one of the leading causes of cancer
deaths. Every year it kills almost six
hundred eighty thousand people around the world. And, doctors find more than one million new
cases each year. The disease is highly treatable if discovered early.
research involved two studies with a total of about one thousand five hundred
people. The larger of the two studies
involved New Yorkers of Ashkenazi Jewish ancestry. Colon cancer is more common in Jews of
eastern European ancestry than in the general population. The other study involved people of different
ethnicities from Chicago, Illinois.
Currently, American medical experts advise colonoscopy
tests for colon cancer to begin at the age of fifty. A colonoscopy can find and remove growths before
they become cancerous. But the test is
invasive and can be uncomfortable.
earlier study expressed support for a test called a virtual colonoscopy. It uses X-ray and computer technology to
search for growths, but cannot remove them.
An estimated one-third of all people are infected with
tuberculosis. Most have latent, or
inactive, cases. They do not suffer
coughing, increased body temperature or other signs of active TB.
each year, about nine million people develop active cases and two million
die. The victims are mostly poor and
live in developing countries. TB is an
ancient bacterial disease. It can be
cured with antibiotics, if patients take all their medicine.
the past century, a skin test has been used to identify latent TB. When cases are found, treatment can prevent
many from becoming active. But the
preventive drugs have a risk of side effects.
skin test depends on the body's reaction to an injection of specially prepared
TB protein. But the test often falsely
identifies people as having latent TB if they have been vaccinated against the
avoid needless treatment, scientists have developed a blood test. This test is designed to identify patients
with a high risk of developing the active form of TB.
international team developed the blood test, called ELISpot. A study showed that the ELISpot blood test
identifies latent TB while giving fewer false positive results.
The researchers say the ELISpot test has been suggested
for use in about twenty countries worldwide.
A report on the test appeared last month in the Annals of Internal
another development, scientists have reported a step toward a better vaccine
against TB. One currently used is
seventy-five years old. The new,
experimental vaccine contains a weakened TB bacterium from a strain of the
current vaccine. The scientists say
their study showed that the experimental vaccine created stronger reactions
against TB than the traditional one.
the new vaccine contains an antibiotic-resistant gene that the scientists do
not want released into the environment.
So future tests of the vaccine are not planned. But research will continue on a similar one
that does not contain the gene.
From space, our planet looks blue. Earth, after all, is mostly covered with
water -- an ocean planet. In September,
an exhibit about the oceans opened at the Smithsonian Institution's National
Museum of Natural History in Washington, D.C.
exhibit explores the beauty and mystery hidden under the sea. It uses the Smithsonian's huge collection of
underwater life to show that all life on our planet is in some way connected to
first thing that a visitor sees is a huge reproduction of a North American
Right Whale. It is a model of Phoenix, a
whale that scientists have studied since she was born near the coast of Georgia
in nineteen eighty-seven. There are only
four hundred of these right whales left.
They were once considered the "right whale" to hunt because they are big
and slow. Phoenix is the biggest of
ninety-seven models in the exhibit.
Near the top of the museum's Sant Ocean Hall are eight
huge video screens showing images of underwater life. The video images give the sensation that
visitors are surrounded with marine life.
The room is also alive with technology.
Twenty-four computer stations show videos and educational programs.
the rarest sights at the exhibit are two giant squids. These secretive creatures live hundreds of
meters beneath the sea. No one had even
seen a living giant squid before scientists captured one on video in two
thousand four. But the Hall has two,
both preserved in a special, clear liquid.
The largest one is more than seven meters long. It was caught near Spain three years ago and
loaned to the Smithsonian.
all the big creatures at the exhibit, there are hundreds of smaller ones of
interest. Many glass containers hold
preserved animal remains that were taken from the museum's collection. With eighty million objects, the Smithsonian's
marine collection is the largest in the world.
Visitors can also look back in time. There is an example of a coelacanth. The coelacanth swam the
ocean sixty-five million years ago.
Scientists thought it had disappeared from the Earth. But this ancient-looking fish was discovered
living near the coast of South Africa in nineteen thirty-eight. Scientists consider it a living fossil.
are of interest to many visitors. They
create feelings of both fear and wonder.
Visitors can see the huge jaws of sharks lined with sharp teeth. There are also examples of sharks gathered
from the deep ocean. They caught the
attention of Elim Babylon. He visited
the Sant Ocean Hall with his grandmother, Sally Babylon.
ELIM BABYLON: "I really like the one back there, like the deep
sea, sea one. It's really cool because
it has all these sharp teeth."
SALLY BABYLON: "We want to share this kind of thing with him and
we want to make him a better steward. I
just want to pass on to him both my appreciation of the beauty of it and also
the care that it takes."
Not everything in the exhibit is preserved. There is a four-hundred-liter tank that
contains over fifty kinds of brightly colored fish and other sea life. The tank is designed to look like a coral
reef in the Indian or Pacific Ocean.
is difficult to believe that some of the creatures shown at the exhibit come
from our own planet. A video, for
example, shows organisms that live near the ocean bottom where volcanic
activity heats the water to hundreds of degrees. Even at these hot volcanic vents, bacteria
survive using the poisonous chemical hydrogen sulfide to create food.
human beings are connected to the ocean in more ways than we know. Very small ocean plants called phytoplankton
create more than half of the world's oxygen.
And it is the ocean that powers the Earth's weather. The exhibit also examines the human
connection to the oceans. It explores
issues such as over-fishing, pollution and climate change. Each is designed to bring visitors a deeper
knowledge of a largely unexplored territory -- our oceans.
SCIENCE IN THE NEWS was written by Mario Ritter, Jerilyn Watson and Caty
Weaver. Our producer was Dana Demange. I'm Bob Doughty.
I'm Barbara Klein. Listen again next
week for more news about science, in Special English, on the Voice of America.