SCIENCE IN THE NEWS - Digest

（单词翻译）

SCIENCE IN THE NEWS -February 5, 2002: Digest

VOICE ONE:

This is Sarah Long.

VOICE TWO:

And this is Bob Doughty¹ with Science in the News, a VOA Special English program about recent developments
in science. Today, we tell about pig organs designed for use in humans. We tell about a gene² for grooming³. We
tell about a new way to tell if someone is lying. And we tell about the death of the world’s oldest man.

((THEME))

VOICE ONE:

Two biotechnology companies say they have developed pigs with organs designed for use in human transplant
operations. They are the first pigs genetically⁵ engineered to keep their organs from being rejected by humans.

Pigs carry a gene that causes production of an enzyme⁶. The enzyme puts sugar molecules⁷ on the surface of pig
organs. The human body ’s defense⁸ system recognizes the organ as foreign and rejects it. The idea was to create
pigs that lacked this gene. The scientists genetically changed a pig embryo⁹, then copied it in a process known as
cloning.

VOICE TWO:

The researchers believe their work is the best hope for people waiting for an organ transplant operation. More
than seventy-thousand people in the United States alone need such an operation to replace organs that no longer
work. Scientists consider pigs to be the best animals to provide organs for people. This is because the organs are
similar.

VOICE ONE:

The two biotechnology companies developed pigs of different sizes. The first four genetically engineered pigs
were born in September and October. The pigs are smaller than normal. Researchers at the University of Missouri
in Columbia developed these pigs. They worked with the Immerge BioTherapeutics Company of Charlestown,
Massachusetts.

The five other pigs are of normal size. They were born in December at the P-P-L Therapeutics Company research
center in Blacksburg, Virginia. P-P-L is the Scottish company that helped create the first cloned animal, Dolly the
sheep, a few years ago. The company says it wants to use the pigs as part of its program to seek a cure for the
disease diabetes¹⁰.

VOICE TWO:

It is very difficult to create genetically engineered pigs. The Missouri group used millions of pig cells. The
researchers made more than three-thousand copies of pig embryos¹¹. They placed the embryos in twenty-eight
mother pigs. Seven baby pigs were born. Four survived. However, some show evidence of heart and blood vessel¹²
problems.

Scientists say that creating these pigs was an important step in solving a major problem in transplanting organs
from animals to humans.

VOICE ONE:

However, scientists say much more work needs to be done to improve this process. Researchers also must solve


the possible problem that pig organs could spread deadly viruses to people. Scientists expect other genes¹³ will
need to be changed before it is safe to place a pig organ in a human being.

In addition, the idea of using pig organs for people raises serious moral questions about the scientific use of
animals. Animal rights activists¹⁴ strongly oppose this research.

((MUSIC BRIDGE))

VOICE TWO:

It is important to most people to look good. For example, we wash our hands and face. We comb our hair. This is
called grooming. Grooming is important for animals too. They clean themselves and remove harmful organisms
from their bodies.

Researchers at the University of Utah School of Medicine have found a group of genes that might be responsible
for grooming activity. The study was led by Mario Capecchi. It appeared in the publication Neuron.

VOICE ONE:

The researchers examined a gene that all animals have. The gene is very important in the early stages of
development. It helps make an animal’s bones, heart, and other organs. The researchers created a group of mice
that lacked the gene. The mice seemed to develop normally.

However, after three weeks, the researchers noted¹⁵ that the mice had missing hair and open wounds. The mice
were grooming themselves too much. They were spending two times as long as healthy mice to get themselves
clean. They licked and bit themselves in some places until their hair was gone.

VOICE TWO:

The researchers wanted to find out if the extreme grooming was a result of some other problem the mice had.
They placed normal mice in the same cage. The genetically changed mice continued to bite their hair until it was
gone in some places. They also did this to the normal mice that had been placed in the cage with them.

Mario Capecchi says people have almost all the same genes as mice. He says the discovery of a grooming gene
could lead to better treatment of some disorders¹⁶ in people. Some people with these disorders spend too much time
grooming. For example, they wash their hands until they bleed.

((MUSIC BRIDGE))

VOICE ONE:

Scientists say they have developed a camera that can help identify when a person is not telling the truth. The new

camera measures the heat released by a person’s face. The scientists say the camera correctly identified lying in
more than eighty percent of the people they tested. They say the device might one day be used in high -level
security operations at airports or border crossings.

James Levine of the Mayo Clinic in Rochester, Minnesota led the study. The scientists based their work on the
theory that people who plan to trick someone release physical or chemical signals.

VOICE TWO:

The researchers worked with scientists at Honeywell Laboratories to develop the
new, heat-imaging technology. Doctor Levine says the camera is designed to
measure small changes in the body. He notes that the flow of blood to the surface of
the skin increases around the eyes when a person lies.

The scientists used twenty people to test the heat-sensing camera. Eight of the
people took part in a crime that was not real. They attacked a human-like object and
stole money from it. They were asked to lie and say they were innocent of the crime.
The twelve other people in the study were told nothing about the make-believe


Lying eyes (bottom) give off
increased heat
crime.

VOICE ONE:

The researchers used the special camera while questioning the twenty people about
the crime. The camera showed that six of the eight people who carried out the crime
had increased heat around their eyes when they lied.

Eleven of the twelve people who knew nothing about the crime were correctly
identified as innocent. When they told the truth, the area around their eyes remained
cool. Lie detection experts say the new camera could be used without suspects
knowing they are being watched.

((MUSIC BRIDGE))

VOICE TWO:

The world’s oldest man died last month. Antonio Todde lived on the Italian island of Sardinia. Mister Todde
was one-hundred-twelve years old. He was less than three weeks away from his one-hundred-thirteenth
birthday.Mister Todde cared for farm animals in the mountains almost all his life. He often said that drinking a
glass of red wine every day helped him live to an old age.

His long life and that of other very old Sardinians is the subject of a study. Luca Deiana of Sassari University is
directing the study. Professor Deiana and his team identified more than two-hundred-twenty Sardinians who were
centenarians --one-hundred years old or older.

VOICE ONE:

The study has produced two major findings. The first is Sardinia’s extremely high number of centenarians. The
island has about one-hundred-thirty-five centenarians for every one-million people. In other western countries,
the average is about seventy-five centenarians for every one-million people.

The second major finding is an unusual rate of female to male centenarians. Sardinia has two women
centenarians for every male centenarian. In central Sardinia there are equal numbers of female and male
centenarians. Studies in other parts of the world have shown a much higher percentage of female centenarians.
Study leaders say there is no single reason why people in Sardinia live so long. They believe the answer is a
combination of genetic⁴ and environmental conditions.

((THEME))

VOICE TWO:

This SCIENCE IN THE NEWS program was written by Nancy Steinbach, Lawan Davis and George Grow. It
was produced by Caty Weaver¹⁷. This is Bob Doughty.

VOICE ONE:

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

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