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AS IT IS - A discovery that could save the lives of millions of newborns
Welcome to AS IT IS, from VOA Learning English. I’m Christopher Cruise.
Today, it’s all about saving babies and preventing pregnancy1…
Kelly Jean Kelly will report on a discovery that could save the lives of millions of newborns.
And I’ll tell you about a study that suggests a possible link between stress in pregnancy and autism or schizophrenia.
But first, we bring you news about a study that predicts a huge unmet need for modern contraceptives in the coming years.
The study predicts millions of married women will not be able to get them over the next few years. Researchers estimate that, by 2015, modern contraceptive methods will not be available to more than 230 million women worldwide who want to use them.Onka Dekker tells us more…
Researchers examined contraceptive use in 194 countries between 1990 and 2010. They designed a mathematical model to estimate the number of married women who used modern, effective contraceptives. These family-planning methods include hormonal2 medicines --drugs that use hormones4 produced by the body. The study estimated the number of women who wanted to use such medicines to prevent pregnancy. But these women were instead using older, traditional birth control methods that sometimes fail.
The model showed that this “unmet need” for modern birth control had decreased over the past 20 years. It also showed a worldwide increase in family planning methods based on hormone3 medicines, such as The Pill and injections. Yet the researchers say the growing world population will result in a greater need for modern family planning methods by 2015. They estimate that 233 million women will not be able to find or use these contraceptive methods.
Ann Biddlecom leads the United Nations Fertility and Family Planning office in New York. She was the main writer of the report. She says there is a lack of support in many countries for family-planning services.
“It comes to, you know, having access not only to the method itself but also better access to quality counseling and options for other kinds of methods to use if one particular method is not working for you.”
She says that, by 2010, the greatest improvements in availability of hormonal birth control methods came in Central America and North Africa. But, she said fewer than one in five married women used any sort of effective birth control in parts of central and western Africa.
Ann Biddlecom says the study only involved married women. She believes the actual number of women needing modern birth control methods by 2015 will be more than 233 million estimated by the researchers.
I’m Onka Dekker.
American researchers have identified a protein that may be linked to neurodevelopmental disorders5 like autism and schizophrenia. The researchers say the level of the protein is affected6 by serious stress women experience during their pregnancy.
The researchers studied women who experienced stress --that is, physical or emotional tension --during pregnancy. They found that such women sent lower levels of a protein to their developing fetuses8 through the placenta than other women. The lowest levels were found in the placentas of boys.
The placenta connects the fetus7 to the wall of the uterus. It passes blood, oxygen and nutrients9 to the unborn child through the mother’s blood.
Tracy Bale is a professor of neurology at the University of Pennsylvania in Philadelphia. She also was the lead researcher in the study. She says the placenta acts as a filter, sorting liquids and other materials within a pregnant woman.
“So, it has genes10 that are expressed that produce these functions. But those genes can change in response to mom’s stress, mom’s dietary changes, mom’s immune responses, etc.”
Autistic individuals have poor communication and social interaction skills. People with schizophrenia imagine unreal things or situations, and have difficulty connecting with people and their environment.
The researchers knew that the two disorders affect males more often and more severely11 than females. So, Dr. Bale and her team began looking for a protein that might explain why that is.
Researchers caused stress in mice during their first week of pregnancy. One week would be the same as the first three months of a human pregnancy. The researchers used the smell of animals that attack mice and noises the mice had not heard before. They then compared the placentas of the stressed mice to those of unstressed mice.
They discovered a protein, called OGT, which seems to be present in higher levels in the female placentas than in the placentas of males. They found that OGT levels were lower in the placentas of the stressed mice compared to those lacking emotional or physical tension.
Investigators12 also found that mice with half the normal amount of OGT had changes in hundreds of different genes known to be involved in brain development. Researchers also examined human placentas after birth and found lower levels of the protein in male placental tissue.
Dr. Bale cannot say for sure whether the protein affects the neurodevelopment of humans. But she says the discovery of OGT could lead to a test to identify babies at increased risk for autism and schizophrenia because of stress during pregnancy.
“You would know which babies to follow to keep an eye on them, to determine if they are at a greater risk. And they may be presenting earlier with different stress-reactivity levels, behavioral changes, etcetera, that would predispose them.”
The study was the work of researchers at the University of Pennsylvania in Philadelphia. A report on the pregnancy stress protein was published in Proceedings13 of the National Academy of Sciences.
Researchers have discovered a way to possibly help protect the health of newborns when they are most at risk of infection. The discovery could save the lives of millions of babies around the world every year.
Kelly Jean Kelly explains.
Each year, bacterial14 and viral infections kill more than two million babies under the age of six months. These newborns are at risk because their natural defenses for fighting disease are too underdeveloped to be helped by vaccines16.
That is why vaccines are usually not given to babies less than two months old. These include vaccinations17 to guard against rotavirus and polio, which children receive as they grow up. Yet in many countries, birth might be the only time a child will have contact with a health-care worker.
Ofer Levy18 studies infectious diseases at Harvard Medical School in Boston, Massachusetts. He says researchers have been looking for a way to protect newborns.
“So we want to design a super vaccine15 that you can give at birth and maybe even get single-shot protection or maybe fewer shots needed. But also by giving it early in life, you close the window of vulnerability inherent to the current vaccine schedule.”
Dr. Levy and researchers at Harvard and Boston Children’s Hospital have identified a small man-made molecule19, called VTX-294. The molecule produces a strong immune response in protective white cells taken from the umbilical-cord blood of newborns.
It activated20 a kind of white blood cell, which is necessary for a vaccine to work. These cells help the body’s natural defenses recognize and destroy disease-causing microorganisms.
Dr. Levy says VTX-294 proved to be stronger than anything tested yet in studies to strengthen newborns’ immune responses.
“When we say potent21, it means you can add very little amount of this compound and get a very powerful response.”
He says researchers are also looking at whether the molecule can strengthen the immune systems of people with cancer so that anti-cancer medicines can be more effective.
A report describing VTX-294 was published in the journal PLOS One.
I’m Christopher Cruise, and that’s “As It Is” in Special English from The Voice of America.
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1
pregnancy
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| n.怀孕，怀孕期 | |
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hormonal
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| adj.激素的 | |
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hormone
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| n.荷尔蒙，激素，内分泌 | |
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hormones
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| n. 荷尔蒙，激素 名词hormone的复数形式 | |
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disorders
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| n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调 | |
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affected
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| adj.不自然的，假装的 | |
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fetus
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| n.胎，胎儿 | |
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fetuses
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| n.胎，胎儿( fetus的名词复数 ) | |
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nutrients
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| n.（食品或化学品）营养物，营养品( nutrient的名词复数 ) | |
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genes
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| n.基因( gene的名词复数 ) | |
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severely
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| adv.严格地；严厉地；非常恶劣地 | |
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investigators
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| n.调查者，审查者( investigator的名词复数 ) | |
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proceedings
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| n.进程，过程，议程；诉讼(程序)；公报 | |
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bacterial
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| a.细菌的 | |
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vaccine
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| n.牛痘苗，疫苗；adj.牛痘的，疫苗的 | |
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vaccines
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| 疫苗，痘苗( vaccine的名词复数 ) | |
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vaccinations
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| n.种痘，接种( vaccination的名词复数 )；牛痘疤 | |
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levy
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| n.征收税或其他款项，征收额 | |
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molecule
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| n.分子，克分子 | |
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activated
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| adj. 激活的 动词activate的过去式和过去分词 | |
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potent
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| adj.强有力的，有权势的；有效力的 | |
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