VOA常速英语2014--研究发现疟原虫也有致命弱点

Study: Malaria 1 Parasite 2 Has Achilles Heel 研究发现疟原虫也有致命弱点

Researchers say they have found a weakness in the malaria parasite that could lead to new drugs to block infection. The mosquito-borne disease kills more than 600,000 people every year, most of them in sub-Saharan Africa – and many of them children.

研究者称在疟疾寄生虫身上发现弱点，这可能会促成研究出阻碍感染的新药物。这种蚊子携带的疾病每年导致60多万人死亡，大多在撒哈拉南部非洲，很多都是儿童。

“When the parasite infects a human it lives not just in your body, but actually inside of red blood cells," said Josh Beck, the first author of the study that appears in the July 16 edition of the journal Nature. "And within the red blood cells it will grow and all the problems that you get when you have malaria are a result of that growth in the red blood cell.”

约书亚·贝克尔是这份发表在7月16日《自然》期刊上研究的主要作者，“当寄生虫感染人体后，就不仅在人体内，还存在红细胞之内。寄生虫在红细胞内生长，感染疟疾时所有的问题都来自寄生虫在红细胞内的生长。”

The World Health Organization says there are five parasite species that cause malaria in humans. Plasmodium Falciparum is the most deadly.

世卫组织称有5种能导致人类疟疾的寄生虫，镰状疟原虫是最致命的。

Beck said it does not just invade the cell. It makes major renovations to its new home.

贝克尔说这种寄生虫不仅侵害细胞，还能在新家做出创新。

“Within the red blood cell the parasite lives inside of a little membrane 3 compartment 4 that’s like a little home for it. And to turn the red blood cell into a proper home for itself it makes all these different proteins that it sends out into the red blood cell that cause it to be modified in a variety of ways – structurally 5, metabolically," he said. "And these cause some of the disease symptoms that are associated with malaria.”

“在红细胞里，寄生虫生长在一个小的膜区室里，像是个小房子。为了让红细胞转变成适合自己的房子，寄生虫会将输送给红细胞的各种蛋白质以各种方式进行结构和代谢上的修改，这就导致与疟疾相关的疾病病症。”

Beck, a postdoctoral research scholar at the Washington University School of Medicine in St. Louis, said researchers have known about the parasite proteins for some time. But they were not sure how the hundreds of different proteins actually left the parasite and entered the red blood cell. So they focused on a protein called HSP101 and found some answers. The proteins pass through a single pore in the parasite’s compartment.

贝克尔是圣路易斯华盛顿大学医学院的博士后研究学者，他说研究者知道寄生虫蛋白质问题多时了。但他们并不确定这数百种蛋白质如何离开寄生虫病进入血红细胞的。所以他们关注一种名为HSP1 01的蛋白质，然后找到一些答案。这些蛋白质穿过了寄生虫膜区室的一个小孔。

“What we found,” said Beck, “is that it looks like it’s a bottleneck 6 right there. Everything from all these diverse pathways funnels 7 into this one specific pore.”

“我们发现小孔就像是个瓶颈，来自各个路径的东西都被导入这个特别的小孔。”

A potential roadblock, if you will.

如果你愿意，是可以设置路障的。

“It is exciting because it suggests that this process could be broadly inhibited 8 by targeting this one specific piece of parasite machinery,” he said. 

“这令人激动，因为这说明可以通过针对这一特别的寄生虫机制来抑制这一过程。”

In lab experiments, when researchers blocked that pore the parasite stopped growing and eventually died. They describe it as “entombing the parasite.” To make that happen in infected people, however, will take a lot more work.

在实验室的试验中，当研究者堵住这一小孔时，寄生虫就停止生长并最终死亡。他们称这一过程为“埋葬寄生虫”。然而要在感染病人身上实现这一过程还需要更多工作。

Beck said, “The way that it will be approached broadly in the field is by screening different small molecule 9 compounds that could potentially be developed into drugs that would interfere 10 with the action. There are a number of different aspects of this pore complex that could potentially be targeted. And so, there’s a lot of different ways to think about designing drugs.”

“这一领域可以采取的广泛办法是筛选各种小分子化合物，这些化合物潜在地可以被开发成能干扰寄生虫生长的药物。这种小孔结构具有各种不同的方面可以加以对付，因此我们从多种角度来开发药物。”

New malaria drugs will be needed. The World Health Organization warns the parasites 11 are building a resistance to the main anti-malarial compound artemisinin. 

目前需要新的疟疾药物，世卫组织警告说，这些寄生虫在对主要的抗疟疾化合物青蒿素产生抗性。

Research also has been done at Australia’s Burnet Institute, which neutralized 12 a malaria parasite in a similar manner. That research also appears in the journal Nature.

澳大利亚的伯内特研究所也在进行研究，研究者以类似的方法对付一种疟疾寄生虫，这项研究也发表在《自然》期刊上。