SCIENCE IN THE NEWS - Autoimmune Diseases: When the Body Sta

SCIENCE IN THE NEWS - Autoimmune Diseases: When the Body Starts to Attack Its Own Cells
By Dana Demange

Broadcast: Tuesday, June 21, 2005

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VOICE ONE:

This is SCIENCE IN THE NEWS, in VOA Special English. I'm Barbara Klein.

VOICE TWO:

And I'm Bob Doughty². On our program this week, we talk about a sickness called lupus and other autoimmune diseases. Autoimmune diseases affect the immune¹ system – the body's natural defenses for fighting disease.

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VOICE ONE:

The immune system normally protects the body against foreign materials, such as viruses and bacteria. Autoimmune diseases result from a failure of the body's own defenses against disease. The immune system loses its ability to tell the difference between foreign materials and its own cells. So, the body starts attacking its own organs and tissues.

VOICE TWO:

There are three kinds of lupus. Discoid lupus affects only the skin and can be identified by red marks on the face or neck. These marks on the skin can be a sign of another form of lupus called systemic lupus. Systemic lupus can affect almost any organ or organ system of the body. When people talk about lupus, they usually mean the systemic form of the disease.

Some kinds of medicines can cause what is called drug-induced lupus. This form of lupus usually goes away when the patient stops using the medicines.

VOICE ONE:

High body temperature and pain in the elbows or knees are common signs of lupus. Other signs are red marks on the skin, feelings of extreme tiredness and a lack of iron in the body.

At different times, the effects of lupus can be either mild or serious. The signs of the disease can come and go. This makes identifying the disease difficult. Many people with lupus also suffer from depression.

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VOICE TWO:

Experts are not sure what causes lupus. Genetics or environmental influences seem to be involved. Lupus has been known to attack members of the same family. Yet, the genes⁴ responsible have yet to be identified. Also, many women with lupus give birth to healthy babies.

Many scientists believe infections may cause lupus. So can extreme bodily or mental tension, commonly known as stress. Two other suspected causes are antibiotic⁵ drugs and hormones⁶ produced by the body.

In fact, hormones might explain why lupus affects women far more often than men. The Lupus Foundation of America says ninety percent of the people with lupus are women. Also, persons of African American, American Indian or Asian ancestry⁷ get infected more often than white women.

Scientists do not know why women are more at risk than men. They think it might have to do with female hormones, like estrogen. Another idea is that it could involve the foreign cells left in a woman's body after a pregnancy⁸.

VOICE ONE:

There is currently⁹ no cure for lupus. Yet doctors have developed ways of treating the disease. Treatments are based on the condition and needs of each patient. No two individuals have the exact same problems. A treatment could include a combination of exercise, stress-reduction and drugs such as painkillers¹⁰ or steroids. Anti-malaria drugs also have been effective.

It has been thirty years since the United States Food and Drug Administration approved a drug especially for treating lupus. Several companies are working to make drugs that can help lupus patients. Organizations like the Lupus Foundation of America are working to increase public understanding of the disease.

Lupus can be life threatening if left untreated. Yet, many patients can lead a normal and healthy life if they follow their doctor's advice. Patients must take their medicines and keep looking for side effects or any new signs of the disease.

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VOICE TWO:

Lupus is not the only autoimmune disease. Doctors and scientists have identified at least eighty other such diseases in which the body attacks its own organs and cells. Some of the diseases attack just one area of the body, like the skin, eye or muscles. Others affect an organ system or even the whole body.

Some of the diseases are well known, such as rheumatoid arthritis¹¹, multiple sclerosis and type-one diabetes¹². Others are less well known and more difficult to identify.

For example, celiac disease is difficult to identify because the signs of the disease are so common. Patients may have low iron levels and experience stomach pain. The uncontrolled expulsion of bodily wastes also is a problem.

Doctors might treat those signs and not know they are caused by celiac disease. Some people develop celiac disease after eating gluten, a protein found in all wheat products. It is not always clear that eating something as harmless as wheat can be bad for a person's health. For some patients, it can be years before the problem is correctly identified.

VOICE ONE:

The United States National Institutes of Health says autoimmune diseases affect an estimated five to eight percent of the country's population. That represents between fourteen million and twenty-two million Americans.

The physical, emotional, and financial cost of autoimmune diseases is huge. Most of those affected¹³ are women. While people of all ages are affected, women who are old enough to have children are especially at risk. This can have an effect on birth rates.

Also, some autoimmune diseases like lupus and scleroderma are more common in African Americans. Diseases such as multiple sclerosis and type-one diabetes are more common among whites. Doctors do not yet know why this is true.

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VOICE TWO:

New drugs are being tested to help treat autoimmune diseases. Some drugs can be a problem because they suppress¹⁴ the immune system. This means the body is less able to defend itself against infections. The side effects of the drugs can end up being as dangerous as the disease itself.

Newer drugs attempt to suppress only one small part of the immune system, not all of it. For example, drugs like Enbrel and Remicade block tumor¹⁵ necrosis factor. This is a protein that causes inflammation, a physical reaction to infection, injury or other causes. These drugs have been useful in treating autoimmune diseases like rheumatoid arthritis, psoriasis, and Crohn's disease. However, the drugs are very costly¹⁶. Some cost more than ten thousand dollars a year.

The drugs also have also been found to increase the risk of cancer. One such drug, called Tysabri, was used to treat multiple sclerosis. But the drug was removed from the market after it was linked to brain infections.

VOICE ONE:

Scientists continue searching for other methods of treatment. For example, some scientists hope to use stem³ cells to replace tissues damaged by disease. Stem cells have the ability to grow into other cells, such as heart, nerve or brain cells.

Some medical experts are working together to improve the way autoimmune diseases are identified and treated. A few years ago, the Johns Hopkins Autoimmune Disease Research Center was formed in the American state of Maryland. The aim of the Center is to bring together experts to improve the study of autoimmune diseases.

Private groups like the Center show how important it is for scientists to share information about such diseases. Because each disease often affects different organs, many experts might be needed to treat the disorder¹⁷. Experts need to know about the most recent medical research and technology. By sharing information about their patients, doctors also can learn from other cases.

VOICE TWO:

Government organizations also are working to increase knowledge about autoimmune diseases. In the United States, the National Institutes of Health created an autoimmune disease research plan two years ago. The plan urges agencies from different areas to work together.

American lawmakers have approved four hundred and fifty million dollars for the project. It is the first national effort to study the causes and treatments of autoimmune diseases.

Both private and government organizations are working to increase public understanding of such diseases. This can help individuals better understand what to do should they develop a health problem. At the same time, medical researchers continue working to help patients have a better quality of life.

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VOICE ONE:

This SCIENCE IN THE NEWS program was written by Dana Demange. Our producer was Cynthia Kirk. I'm Barbara Klein.

VOICE TWO:

And I'm Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.

1 immune   

adj.免疫的，有免疫力的，不受影响的，免除的

参考例句：

• I am immune from the disease,for I had it once.我对这病有免疫力，因为我已得过一次了。
• Be immune from corruption.拒腐蚀，永不沾。

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 stem   

n.茎，干，船首，词干，血统；vt.堵住，阻止，抽去梗；vi.起源于，发生

参考例句：

• Cut the stem cleanly,just beneath a leaf joint.把茎切整齐点，正好切在叶根下。
• The ship was in a blaze from stem to stern.整艘船从头到尾都着火了。

4 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

5 antibiotic   

adj.抗菌的；n.抗生素

参考例句：

• The doctor said that I should take some antibiotic.医生说我应该服些用抗生素。
• Antibiotic can be used against infection.抗菌素可以用来防止感染。

6 hormones   

n. 荷尔蒙，激素 名词hormone的复数形式

参考例句：

• This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
• The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。

7 ancestry   

n.祖先，家世

参考例句：

• Their ancestry settled the land in 1856.他们的祖辈1856年在这块土地上定居下来。
• He is an American of French ancestry.他是法国血统的美国人。

8 pregnancy   

n.怀孕，怀孕期

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕早期常有恶心的现象。
• Smoking during pregnancy increases the risk of miscarriage.怀孕期吸烟会增加流产的危险。

9 currently   

adv.通常地，普遍地，当前

参考例句：

• Currently it is not possible to reconcile this conflicting evidence.当前还未有可能去解释这一矛盾的例证。
• Our contracts are currently under review.我们的合同正在复查。

10 painkillers   

n.止痛药( painkiller的名词复数 )

参考例句：

• The doctor gave him some painkillers to ease the pain. 医生给了他一些止疼片以减缓疼痛。 来自辞典例句
• The primary painkillers - opiates, like OxyContin - are widely feared, misunderstood and underused. 人们对主要的镇痛药——如鸦片剂奥施康定——存在广泛的恐惧、误解，因此没有充分利用。 来自时文部分

11 arthritis   

n.关节炎

参考例句：

• Rheumatoid arthritis has also been linked with the virus.风湿性关节炎也与这种病毒有关。
• He spent three months in the hospital with acute rheumatic arthritis.他患急性风湿性关节炎，在医院住了三个月。

12 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

13 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。

14 suppress   

vt.压制，镇压，查禁，抑制，阻止

参考例句：

• He continued to suppress the people and serve the imperialists.他继续镇压人民，为帝国主义效劳。
• She was struggling to suppress her sobs.她拼命不让自己哭出来。

15 tumor   

n.（肿）瘤，肿块(英)tumour

参考例句：

• He was died of a malignant tumor.他死于恶性肿瘤。
• The surgeons irradiated the tumor.外科医生用X射线照射那个肿瘤。

16 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

17 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。