VOA慢速英語:沙門氏菌已轉化為殺死癌細胞的超級戰(zhàn)士

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

這里是美國之音健康報道。

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

許多人都不會把讓數(shù)百萬人生病的細菌當做朋友，但是科學家Roy Curtiss確實這樣。

"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."

是這樣的，我經常尋找大家經常認為是敵人的細菌的一些新用途，它們是我的朋友。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是亞利桑那州一家生物設計研究所的微生物學家。在我們討論沙門氏菌的時候他用“蟲子”這個常見的字眼來代表細菌和病毒。

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專門研究沙門氏菌，并認為人們給它扣了一個“壞名聲”。換句話說，大多數(shù)人當聽到沙門氏菌的時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.

沙門氏菌是對食物來講最常見的細菌或者污染物，存在于一些未煮熟的肉類，雞蛋和牛奶中。沙門氏菌可以引起身體發(fā)熱和腹部疼痛。患者可能會感到惡心，出現(xiàn)嘔吐。

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

沙門氏菌其中的一種菌種還會造成傷寒病。

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.

所以人們才會很自然的認為這種細菌能夠給人類帶來疾病，從而背上了不好的名聲。那么問題來了：什么時候食源性細菌才能成為你的朋友?答案：當這種細菌可以幫助人類殺死癌細胞的時候。

"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."

每年有數(shù)百萬人因沙門氏菌生病，但是經過基因轉換工程后的沙門氏菌在未來的某一天可以被用來作為消滅癌癥的武器。就像一句古話說的那樣：我敵人的敵人，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.

美國和德國的研究人員已經把沙門氏菌轉化稱了對抗腫瘤癌癥的武器。Roy Curtiss稱這種細菌可以使癌細胞消失。

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.

這是一個實驗。首先，研究人員改變了沙門氏菌的內部基因轉而去殺死癌細胞。研究人員向小老鼠體內注射了人類癌細胞。然后他說，他們將轉換過基因的沙門氏菌注射到動物體內。

"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."

我們對沙門氏菌進行了基因修飾使其無法在健康組織中正常生存，但是腫瘤對于這些基因來講是一個很好的生存條件，這是一個營養(yǎng)豐富的環(huán)境他們可以瘋狂的生長，然后就可以發(fā)揮修改過基因的沙門氏菌的作用來殺死癌細胞。

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

記者稱這一研究發(fā)表在了醫(yī)學雜志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說在人類身上進行修改過的沙門氏菌基因實驗還需要等一段時間。他希望能夠對細菌進行更多修飾來增加其抗癌的作用。

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.

沙門氏菌不會是對抗癌癥的唯一治療標準。相反，Curtiss希望修改細菌基因研究將會更廣泛應用到傳統(tǒng)治療方法當中，例如化療和放射療法。

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)