VOA标准英语2011--New Treatment Potential Found in Popular

New Treatment Potential Found in Popular TB Drug

Scientists say new insights into a common tuberculosis² drug will make it possible to shorten the treatment period for patients infected with TB.
The drug "pyrazinamide" is widely used in combination with other drugs to treat active tuberculosis infections. Now, doctors are learning more about how it works - and calling the new information a "breakthrough."
The standard therapy for treating active tuberculosis infections today is to give patients a combination of four drugs, taken over a period of six months.
Forty years ago, TB treatment took much longer - until what experts call the "breakthrough drug" came along.
Dr Clifton Barry, who directs tuberculosis research at the National Institutes of Health, said, “Pyrazinamide allowed that period to be shortened to six months - compared to two years. It was dramatic breakthrough in the 1970s.”
He said scientists have long known that pyrazinamide, by itself, does not destroy the active TB bacterium³. But research has now revealed that the drug does kill the latent form of the microbe, which does not cause observable symptoms.
With their improved understanding of how pyrazinamide actually works at the molecular⁴ level, Barry said scientists will be able to design a more potent¹ form of the drug that could shorten the duration of TB treatment from six months to just two.
“Before, it was a completely empirical approach: Just try anything you can and see if that kills the bacteria a little more quickly or under certain non-replicating conditions. Now, with [our knowledge of the drug's] molecular mechanism⁵, all of a sudden we can use all the tools of modern drug discovery, which means structure-based, protein-targeted approaches,” said Barry.
Dr. Barry believes this new, more targeted use of pyrazinamide could finally break the back of the global TB epidemic⁶, which has infected nearly one third of the world’s population. While more than 8 million people are sick with the highly contagious⁷ active form of TB, an estimated two billion people carry the latent form - with no symptoms.
“Remember that every case that develops into active disease spreads it to at least 10 more people. And so instead of treating those 10 people, if we start to treat the people before they get sick - who are asymptomatic - then we can really make a huge difference in how many people get sick with the disease."
Experts are applauding the new insights into this important TB drug, and the prospects⁸ for improved therapies. But they say the best way to slow the global tuberculosis epidemic is to match these treatment gains with similar strides toward faster, more reliable TB testing.

1 potent   

adj.强有力的，有权势的；有效力的

参考例句：

• The medicine had a potent effect on your disease.这药物对你的病疗效很大。
• We must account of his potent influence.我们必须考虑他的强有力的影响。

2 tuberculosis   

n.结核病，肺结核

参考例句：

• People used to go to special health spring to recover from tuberculosis.人们常去温泉疗养胜地治疗肺结核。
• Tuberculosis is a curable disease.肺结核是一种可治愈的病。

3 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

4 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

5 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

6 epidemic   

n.流行病；盛行；adj.流行性的，流传极广的

参考例句：

• That kind of epidemic disease has long been stamped out.那种传染病早已绝迹。
• The authorities tried to localise the epidemic.当局试图把流行病限制在局部范围。

7 contagious   

adj.传染性的，有感染力的

参考例句：

• It's a highly contagious infection.这种病极易传染。
• He's got a contagious laugh.他的笑富有感染力。

8 prospects   

n.希望，前途(恒为复数)

参考例句：

• There is a mood of pessimism in the company about future job prospects. 公司中有一种对工作前景悲观的情绪。
• They are less sanguine about the company's long-term prospects. 他们对公司的远景不那么乐观。