SCIENCE IN THE NEWS - Parkinson's Disease

SCIENCE IN THE NEWS - Parkinson's Disease
By Caty Weaver¹ and Oliver Chanler

Broadcast: Tuesday, February 08, 2005

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VOICE ONE:

This is SCIENCE IN THE NEWS, in VOA Special English. I'm Sarah Long.

VOICE TWO:

And I'm Bob Doughty². On our program this week, we tell about Parkinson's disease, a disorder³ of the central nervous system.

VOICE ONE:

 
AP Photo
Many people around the world live with Parkinson's disease. In the United States, Parkinson's affects about five hundred thousand people. There has been recent interest in the disease because of some of those affected⁴ are very well known.

When Karol Wojtyla was elected pope⁵ in nineteen seventy-eight, he changed the image of the leader of the Roman Catholic⁶ Church. The new pope, John Paul the second, was known as a man who liked physical exercise. He swam and walked great distances.

Muhammed Ali also showed great energy and power as he became the boxing champion of the world. He was probably one of the sport's greatest competitors of the twentieth century.

However, as both men grew older, they began to change. Their energy began to disappear. Their movements became slower. Their faces seemed to be made of stone. Age makes all people lose the energy they had when they were younger. However, it was not age that changed these men so much. Their physical changes were caused by a sickness known as Parkinson's disease.

VOICE TWO:

Parkinson's disease is a disorder of the central nervous system. It is a disease that makes its victims increasingly unable to move. It affects a small area of cells in the middle of the brain called the substantia nigra. The cells slowly lose their ability to produce a chemical called dopamine. The reduced levels of dopamine can result in one or more of the general signs or symptoms of Parkinson's disease.

These symptoms include shaking of the arm or leg on one side of the body. Other symptoms are a general slowness of movement, or severe difficulty in moving the arms and legs. Another is difficulty walking and keeping balanced while standing⁸ or walking.

Other signs observed in some people include restricted or decreased movement of the face. Also, victims of Parkinson's disease can feel sad or worried. Victims may swallow less often than normal. And, they may have difficulty forming words while talking.

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VOICE ONE:

Parkinson's disease is named after James Parkinson. He was a British doctor who first described the disease in Eighteen-Seventeen. But Doctor Parkinson did not know what caused it.

During the nineteen sixties, research scientists discovered chemical and other changes in the brains of people suffering from the disease. These discoveries led to medicines to treat Parkinson's disease. However, the cause of the disease is still a mystery.

VOICE TWO:

Most people have what is called idiopathic Parkinson's disease. Idiopathic means that the cause is unknown. Patients who develop the disease attempt to link it to some cause they can identify. These can include an accident, a medical operation, or emotional problems.

Most doctors, however, reject the idea of any direct link between these events or problems and Parkinson's disease. The doctors note that other people with similar problems do not develop a movement disorder such as Parkinson's disease. However, doctors say such events or problems may cause signs of the disease to be seen earlier than normal.

VOICE ONE:

There are other forms of Parkinson's disease. Some medicines for other problems can cause disorders⁹ similar to Parkinson's disease. These include medicines used to treat older people who see things that do not exist. And they include drugs used to treat people suffering from extreme tension or stomach problems.

The disease encephalitis also can cause movement problems and other disorders like those of Parkinson's disease. In the early twentieth century, encephalitis spread to many parts of the world. Many victims of the disease had symptoms similar to Parkinson's disease. This led to scientific investigations¹⁰ into the possibility that a virus caused Parkinson's disease.

However, no evidence was found to support this theory. One reason for rejecting the theory is that Parkinson's disease cannot be passed from one person to another the way other viral diseases can.

VOICE TWO:

Another common theory is that people with Parkinson's disease could pass it to their children. There are examples of many members of families having the disease.

Last month, the publication Lancet reported additional genetic¹¹ evidence. It said a change in just one gene⁷ may affect the risk of Parkinson's disease. Researchers found that one in every sixty people with Parkinson's have changes in the gene called L-R-R-K-two. The researchers said the genetic changes could be responsible for five percent of all cases in people with a family history of the disorder. They said it also could cause up to two percent of idiopathic Parkinson's.

VOICE ONE:

Also, a small study suggested that chemical products used to kill insects could increase the risk of the disease. American researchers found that people who sprayed such products had two times the risk of developing Parkinson's than other people. They found farmers also had an increased risk, although much smaller.

Most of those suffering from the disease are older people. It reportedly affects one of every one-hundred people over sixty years old. However, fifteen percent of patients develop the disease before they are fifty years old. Also, it affects men a little more often than it affects women. And Parkinson's disease can be found among people in all parts of the world.

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VOICE TWO:

Parkinson's disease does not cause death for those suffering from the condition. New treatments to ease symptoms of the disease make it possible for many patients to continue to live almost normally. Patients who have lost their ability to do many things may be able to regain¹² some of their old abilities with treatment.

Perhaps the drug most commonly used to treat the disease is levodopa. When it reaches the brain, levodopa is changed to dopamine. It replaces the dopamine lacking in patients with Parkinson's disease.

Levodopa helps deal with the signs of the disease. It does not, however, prevent more changes in the brain caused by the disease. Levodopa can produce bad effects in some people. These side effects include feeling extremely sick to the stomach. To prevent this from happening, other substances can be combined with levodopa.

Most other drugs used to treat Parkinson's disease are designed to increase the amount of dopamine in the brain.

VOICE ONE:

Another way of treating Parkinson's disease is a medical operation. One such operation is called a pallidotomy. It was used often in the past to treat the disease. However, it was used less often after the discovery of levodopa.

More recently, improved technology has increased the chances of successful pallidotomies. The operation involves placing electrical devices directly on the brain. These devices target cells in the area that cause unwanted movements of the body. The most serious risk from this treatment is the possibility of the patient suffering a stroke.

VOICE TWO:

The most recent development in treatment of Parkinson's disease is brain tissue transplants¹³. This involves replacing tissue in areas of the brain that cause symptoms of the disease. Early experiments involved brain tissue from unborn babies. Doctors said the method appeared to have successful results.

However, the experiments became a subject of moral debates among persons opposed to the ending of unwanted pregnancies¹⁴.

Researchers have begun working with genetically¹⁵ changed cells and different animal cells that can be made to produce dopamine. Still, most doctors agree that such operations should be considered only after it is clear that drugs are not effective in dealing¹⁶ with the signs of Parkinson's disease.

VOICE ONE:

There is no way to prevent or cure Parkinson's disease. So, the victims of the disease need help in many ways. Throughout the world, there are groups that provide education and support services for patients and their families learning to live with the disease.

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VOICE TWO:

This SCIENCE IN THE NEWS program was written by Oliver Chanler and Caty Weaver. 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.

1 weaver   

n.织布工；编织者

参考例句：

• She was a fast weaver and the cloth was very good.她织布织得很快，而且布的质量很好。
• The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。

2 doughty   

adj.勇猛的，坚强的

参考例句：

• Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质：脾气倔强，性格刚强。
• The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。

3 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

4 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

5 pope   

n.（罗马天主教的）教皇

参考例句：

• The Pope is the spiritual leader of many Christians.教皇是众多基督徒的宗教领袖。
• The Pope is the supreme leader of the Roman Catholic Church.教皇是罗马天主教的最高领袖。

6 catholic   

adj.天主教的；n.天主教徒

参考例句：

• The Pope is the supreme leader of the Roman Catholic Church.教皇是罗马天主教的最高领袖。
• She was a devoutly Catholic.她是一个虔诚地天主教徒。

7 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

8 standing   

n.持续，地位；adj.永久的，不动的，直立的，不流动的

参考例句：

• After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
• They're standing out against any change in the law.他们坚决反对对法律做任何修改。

9 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

10 investigations   

（正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究

参考例句：

• His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查，但没有发现什么。
• He often sent them out to make investigations. 他常常派他们出去作调查。

11 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

12 regain   

vt.重新获得，收复，恢复

参考例句：

• He is making a bid to regain his World No.1 ranking.他正为重登世界排名第一位而努力。
• The government is desperate to regain credibility with the public.政府急于重新获取公众的信任。

13 transplants   

n.（器官、皮肤、头发等的）移植( transplant的名词复数 )；移植的器官，移植物

参考例句：

• The heart transplants have been read about and discussed everywhere. 人们已读到关于心脏移植的报道，到处都在议论此事。 来自《简明英汉词典》
• A number of terms are used in various classifications of transplants. 移植物的各种分类中应用了一系列的名词。 来自辞典例句

14 pregnancies   

怀孕，妊娠( pregnancy的名词复数 )

参考例句：

• Since the wartime population needed replenishment, pregnancies were a good sign. 最后一桩倒不失为好现象，战时人口正该补充。
• She's had three pregnancies in four years. 她在四年中怀孕叁次。

15 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

16 dealing   

n.经商方法，待人态度

参考例句：

• This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
• His fair dealing earned our confidence.他的诚实的行为获得我们的信任。