VOA慢速英语2015 "大事件":治疗艾滋新方法

New Treatment for AIDS Called a ‘Big Deal’ "大事件":治疗艾滋新方法

VOA's Jessica Berman reported this story from Washington, D.C. for VOA News.

Researchers in the United States are changing healthy muscle cells to make them produce genetic² information that could possibly neutralize³ HIV, the virus that causes AIDS in humans. Scientists at Scripps Research Institute in Jupiter, Florida, tested the treatment on a type of monkey.

The immune systems of these monkeys were repeatedly exposed to simian⁴ immunodeficiency virus (SIV), the primate⁵ version of HIV. The animals never became infected after a treatment to change the muscle cells.

Michael Farzan is the lead researcher on the project. He and his team administered the virus to the monkeys in increasing amounts. They started with a dose that easily passes SIV to the untreated monkeys in the control group. But the treated monkey remained uninfected. Then, the scientists doubled the dose for each re-exposure to the virus.

Mr. Farzan said even monkeys that received 16 times the usual dose were protected. They did not get infected with SIV.

"We continued to administer the virus, doubling the dose each time. We've now gone to -- with six doses that were capable of infecting control ((untreated)) animals -- we've gone to 16 times that."

Making HIV kill itself

Traditional vaccines⁶ train the immune system to recognize and destroy disease. But experimental AIDS vaccines fail at this because the virus is always mutating, or changing, to avoid destruction. HIV and SIV are both able to do this because of a surface protein that mutates to avoid the body’s immune system. 

Mr. Farzan says this new drug treatment is based on tricking HIV. The drug tricks HIV into exposing this important viral surface protein.

The experimental compound attaches to the part of the virus that is always mutating to avoid the immune system. Once attached, a second protein makes the virus self-destruct. The virus never has a chance to infect cells.

"Because HIV is sort of fooled into thinking that it's binding⁷ the cell, it undergoes the changes that it would normally do when it's ready to enter a cell. And those changes, um, if it's not near a cell, inactivate⁸ the virus."

The muscle cells continually produce cells that fool the virus into self-destruction.

Mr. Farzan says the compound has the potential both to protect against infection with HIV and to fight the virus in infected people. The team wants to begin testing human patients who are not able to take antiretroviral drugs.  

The researchers published their findings in the journal Nature.

According the World Health Organization, almost 78 million people have been infected with the HIV virus. About 39 million people have died of HIV.

In 2013 alone, 35 million people were living with HIV or AIDS and 1.5 million died from AIDS.

The virus still affects Sub-Saharan Africa more severely⁹ than any other part of the world.

Nearly one in every 20 adults there is living with HIV. This represents almost 71% of the people living with HIV worldwide.

Words in This Story

genetic – adj. of, relating to, or involving genes¹⁰

neutralize – v. to stop (someone or something) from being effective or harmful

immune system – n. the system that protects your body from diseases and infections

primate – n. any member of the group of animals that includes human beings, apes, and monkeys

dose- – n. the amount of a medicine, drug, or vitamin that is taken at one time

expose – v. subject to risk from a harmful action or condition

mutate – v. biology to cause a gene¹ to change and create an unusual characteristic in a plant or animal

antiretroviral – adj. acting, used, or effective against retroviruses <antiretroviral drugs> <antiretroviral therapy>

1 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。

2 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。

3 neutralize   

v.使失效、抵消，使中和

参考例句：

• Nothing could neutralize its good effects.没有什么能抵消它所产生的好影响。
• Acids neutralize alkalis and vice versa.酸能使碱中和碱，亦能使酸中和。

4 simian   

adj.似猿猴的；n.类人猿，猴

参考例句：

• Ada had a wrinkled,simian face.埃达有一张布满皱纹、长得像猿猴的脸。
• Curiosity is the taproot of an intellectual life,the most valuable of our simian traits.好奇是高智生命的根源，也是我们类人猿特征中最有价值的部分。

5 primate   

n.灵长类（目）动物，首席主教；adj.首要的

参考例句：

• 14 percent of primate species are highly endangered.14%的灵长类物种处于高度濒危状态。
• The woolly spider monkey is the largest primate in the Americas.绒毛蛛猴是美洲最大的灵长类动物。

6 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

7 binding   

有约束力的，有效的，应遵守的

参考例句：

• The contract was not signed and has no binding force. 合同没有签署因而没有约束力。
• Both sides have agreed that the arbitration will be binding. 双方都赞同仲裁具有约束力。

8 inactivate   

v.使…不活跃

参考例句：

• We put bacteria in an environment at low temperature to inactivate them.我们将细菌置於低温的环境中使之失去活性。
• Food processing destroys some nutrients,but can also inactivate toxins and increase the availability of other nutrients.食物加工破坏一些营养物质，但也可以灭活毒素，并增加其他营养物质的可用性。

9 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

10 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