This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.
And I'm Pat Bodnar. This week: People with H.I.V. are warned of the dangers if they go for periods without their medicine ...
A study offers good news for parents of babies born prematurely …
And a Valentine's Day report on mother love -- was it a bridge-builder to humanity?
American health officials are advising people with H.I.V. to take their medicine every day and not to stop. They warn that breaks in treatment could sharply increase the risk of AIDS or death.
Experts at the National Institutes of Health say their warning is based on findings from a large study. It examined the effects of controlled suspensions in drug treatment. The study involved more than five thousand people.
Medicines can suppress H.I.V., the virus that develops into AIDS. But the daily treatment can be very costly. And there can be serious short- and long-term side effects.
Researchers at the National Institutes of Health began the study in January of two thousand two. They called it SMART -- Strategies for Management of Anti-Retroviral Therapy. They wanted to study six thousand people around the world. The scientists reached more than ninety percent of the target before they halted new enrollments last month. They did so earlier than planned.
The researchers tested all the people for the level of CD-four cells in their blood. These cells are a measure of the strength of the body’s defense system.
The researchers divided the patients into two groups. One group stayed on continuous anti-retroviral therapy. They took their medicines every day. The others took them periodically. They took the drugs only when their CD-four count fell below two hundred fifty cells per cubic millimeter of blood. The patients would go off the drugs again once their cell count climbed above three hundred fifty.
The study found that these patients were two times as likely to develop AIDS or to die as the group on continuous treatment.
In November, an independent scientific committee looked at the information gathered from the study. The Data and Safety Monitoring Board called for an end to new enrollments.
Just over half of the patients were in the United States, but the study involved people in thirty-three countries. Almost three fourths were men and the average age at entry was forty-six. The study cost more than seventy million dollars.
The results were not what many AIDS activists and experts had hoped for. Some smaller studies had raised hopes for the idea of periodic anti-retroviral therapy. Now, some people worry that the new findings will end the search for a method that might prove successful.
This is SCIENCE IN THE NEWS in VOA Special English from Washington.
For children born with extremely low birth weights, life begins as a struggle. More than one-fourth of low birth-weight babies experience problems such as delayed development, blindness or cerebral palsy. Only two percent of normal birth-weight boys and girls experience these problems.
But researchers in Canada are reporting some good news. A study followed the development of low birth-weight babies into young adults. And it compared their development with individuals who had been born at a normal weight. The researchers found that the two groups had similar levels of education, employment and independence.
Saroj Saigal led the researchers. She is a professor at McMaster University in Hamilton, Ontario. The United States National Institute of Child Health and Development provided financial aid for the study. The Journal of the American Medical Association published the results earlier this month.
The Canadian study involved one hundred sixty-six people. They were born between nineteen seventy-seven and nineteen eighty-two. At birth, each weighed only between one-half and one kilogram.
The researchers compared this group with one hundred forty-five people who were a normal weight at birth. The two groups were compared as eight-year-olds, as older children and as young adults.
The researchers found similar rates of high school completion. Eighty-two percent in the low birth-weight group had a high school education, compared to eighty-seven percent in the other group. About one-third of the members in each group were still continuing their education beyond high school.
Forty-eight percent of those in the low birth-weight group were permanently employed. This compared to fifty-seven percent in the normal birth-weight group. The researchers say this difference is not major. Nor did they find major differences in the rates of those who lived independently, were married or were parents.
Doctor Saigal says more studies are needed. But she says the findings should provide hope for parents worried about the long-term future of babies born too soon.
Valentine's Day, February fourteenth, is a holiday all about love. So this is a good day to talk about a special kind of love: mother love.
There is a new book called "The Bridge to Humanity." It argues that a need for expressions of love helped early humans learn to live cooperatively.
VOA’s Mike O’Sullivan spoke with the writer. Walter Goldschmidt is an anthropologist. He studies the physical, social and cultural development of humans. Professor Goldschmidt is ninety-two. He retired from the University of California, Los Angeles. He holds the honor of professor emeritus of anthropology and psychiatry.
Biologists know that creatures sometimes sacrifice themselves in the interest of their children. They follow the biological urge to protect the genetic future of a population. Scientists who study human development know that people sometimes act against their biological interest. Some biologists say this is caused by the "selfish gene."
So how did humans escape the control of their biology and still survive? Professor Goldschmidt says this question has long been a mystery about human evolution. He thinks the answer might have something to do with a mother’s love.
Humans raise their children for an unusually long time. Professor Goldschmidt says the love of a mother does more than just help the social development of her children. He argues that this special relationship led to the social relations that led to societies.
He says human culture began to develop with homo habilis, an early human that made simple tools. The anthropologist says continual growth of the brain after that gave humans the ability to think logically. And he thinks logical thought developed in two directions: one through language and the other through tool-making.
He says both skills are the result of the same mental abilities. These skills developed within ancient communities and, in turn, aided human development. Professor Goldschmidt sees this process repeated today. He sees it in families as children interact with and learn from their parents.
Walter Goldschmidt says physical and emotional ties are important. These are not just wants, he says, but needs. Healthy development depends on them. And he says the same is true of other populations of mammals. Professor Goldschmidt argues that this need in people defeats the so-called selfish gene.
The author of "The Bridge to Humanity" says evolution is a story of cooperation as much as competition. He says the part played by the loving mother is a missing link to understanding human development.
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SCIENCE IN THE NEWS was written by Caty Weaver and George Grow. Cynthia Kirk was our producer. I'm Bob Doughty.
And I'm Pat Bodnar. Internet users can read and listen to our programs at voaspecialenglish.com. Join us again next week for more news about science in Special English on the Voice of America.