VOA慢速英语:沙门氏菌已转化为杀死癌细胞的超级战士

From VOA Learning English, this is the Health and Lifestyle Report.

这里是美国之音健康报道。

Not many people consider a bacterium that makes millions of people sick ... a friend. But scientist Roy Curtiss does.

许多人都不会把让数百万人生病的细菌当做朋友，但是科学家Roy Curtiss确实这样。

"Yeah, I'm always looking for new uses for a bug that most people think is an enemy -- it's my friend. And I would like to make it your friend too."

是这样的，我经常寻找大家经常认为是敌人的细菌的一些新用途，它们是我的朋友。我也希望大家能和它做朋友。

Roy Curtiss is a microbiologist at the Biodesign Institute at Arizona State University in Tempe, Arizona. He uses the word ‘bug,' a common expression for a germ or virus, when talking about Salmonella bacteria.

Roy Curtiss是亚利桑那州一家生物设计研究所的微生物学家。在我们讨论沙门氏菌的时候他用“虫子”这个常见的字眼来代表细菌和病毒。

Mr. Curtiss studies Salmonella and thinks it "gets a bad rap." In other words, many people only have bad thoughts when they hear the word, "Salmonella."

Curtiss专门研究沙门氏菌，并认为人们给它扣了一个“坏名声”。换句话说，大多数人当听到沙门氏菌的时候想到的只是不好的想法。

What is Salmonella?

Salmonella is the most common bacteria to harm, or contaminate, food. It is found in undercooked meats, eggs and milk. Salmonella can cause a higher than normal body temperature and pain in the abdomen. The person may feel sick, throwing up whatever is in the stomach.

沙门氏菌是对食物来讲最常见的细菌或者污染物，存在于一些未煮熟的肉类，鸡蛋和牛奶中。沙门氏菌可以引起身体发热和腹部疼痛。患者可能会感到恶心，出现呕吐。

One form of Salmonella is also responsible for the disease typhoid.

沙门氏菌其中的一种菌种还会造成伤寒病。

So, it is only natural that a bacterium that makes people sick is given a bad rap. The question is, "When does a food-borne bacterium become your friend?" The answer: when it helps to kill cancer cells.

所以人们才会很自然的认为这种细菌能够给人类带来疾病，从而背上了不好的名声。那么问题来了：什么时候食源性细菌才能成为你的朋友?答案：当这种细菌可以帮助人类杀死癌细胞的时候。

"The enemy of my enemy is my friend."

Millions of people are sickened each year by Salmonella. But a genetically-engineered version of the bacteria may someday be used as a weapon against cancer. As the old saying goes, "The enemy of my enemy is my friend."

每年有数百万人因沙门氏菌生病，但是经过基因转换工程后的沙门氏菌在未来的某一天可以被用来作为消灭癌症的武器。就像一句古话说的那样：我敌人的敌人，就是我的朋友。Researchers in the United States and Germany have turned Salmonella into a weapon against cancerous tumors. Roy Curtiss says the bacteria can make the cancer cells disappear.

美国和德国的研究人员已经把沙门氏菌转化称了对抗肿瘤癌症的武器。Roy Curtiss称这种细菌可以使癌细胞消失。

The experiment

And here is the experiment. First, the researchers changed the genes of the Salmonella to die in healthy tissues but kill cancer cells. They put human cancer cells into mice. Then, he says, they put the genetically-modified Salmonella bacteria into the animals.

这是一个实验。首先，研究人员改变了沙门氏菌的内部基因转而去杀死癌细胞。研究人员向小老鼠体内注射了人类癌细胞。然后他说，他们将转换过基因的沙门氏菌注射到动物体内。

"We genetically modify the Salmonella so that it is unable to survive in healthy tissues, but has a preferential homing (attraction) to tumors, which [are] a very nutrient-rich environment where they grow like crazy and, in so doing, kill the cancer cells within the tumor."

我们对沙门氏菌进行了基因修饰使其无法在健康组织中正常生存，但是肿瘤对于这些基因来讲是一个很好的生存条件，这是一个营养丰富的环境他们可以疯狂的生长，然后就可以发挥修改过基因的沙门氏菌的作用来杀死癌细胞。

A report describing the work was published in the medical journal mBio.

记者称这一研究发表在了医学杂志mBio上。

Roy Curtiss says it will be a while before the genetically-modified version of Salmonella is tested on human beings. He wants to make more changes to the bacteria to increase their cancer-killing power.

Roy Curtiss说在人类身上进行修改过的沙门氏菌基因实验还需要等一段时间。他希望能够对细菌进行更多修饰来增加其抗癌的作用。

Salmonella would not be a stand-alone treatment for fighting cancer. Instead, Mr. Curtiss hopes the genetically-modified bacteria will be used in addition to more traditional therapies, such as chemotherapy and radiation.

沙门氏菌不会是对抗癌症的唯一治疗标准。相反，Curtiss希望修改细菌基因研究将会更广泛应用到传统治疗方法当中，例如化疗和放射疗法。

I'm Anna Matteo.

VOA science reporter Jessica Berman wrote this report from Washington, D.C.. Anna Matteo adapted it for Learning English. George Grow was the editor.

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Words in This Story

bad rap – idiomatic expression a negative and often undeserved reputation —often used with bum or bad (Example: He got a bad (or bum) rap by the press.)

borne – adj. carried by : spread by — used in combination as in "waterborne" and "airborne"

genetically-modified - adjective containing genetic material that has been artificially altered so as to produce a desired effect

tumor – n. a mass of tissue found in or on the body that is made up of abnormal cells

contaminate – v. to make (something) dangerous, dirty, or impure by adding something harmful

chemotherapy – n. medical the use of chemicals to treat or control a disease (such as cancer)

radiation – n. medical the use of controlled amounts of radiation for the treatment of diseases (such as cancer)