VOA慢速英语2014 AS IT IS 2014-03-16 Device Finds Malaria Infections in Seconds 通过医疗设备发现人体内疟疾感染只需几秒钟

 

AS IT IS 2014-03-16 Device Finds Malaria¹ Infections in Seconds 通过医疗设备发现人体内疟疾感染只需几秒钟

Hello, and welcome to As It Is, from VOA Learning English. I’m Steve Ember in Washington.

Today on the program, we report on how antibacterial soap manufacturers must prove their products are more effective than normal soap and water.

But first, researchers have developed a medical device which they say can find malaria infections in the human body. The laser beam scanner is the first device that can find the sometimes-deadly disease without going inside the body. VOA reporter Christopher Cruise has more.

Device Finds Malaria Infections in Seconds

At the present time, a trained medical worker needs costly² equipment, a person’s blood and a lot of time to know if a person has been infected with malaria. Trained workers, equipment and time are not always available in poor parts of the world.

The newly-developed device only needs a person to place a finger on a laser device.

Dr. Dmitri Lopotko is a researcher at the department of biochemistry and cell biology at Rice University in Houston, Texas.

“We shine a very short light pulse through the skin. And this light pulse is absorbed only by malaria parasites⁴ because of the wavelength⁵ we use. And in response to this short light pulse, the parasite³ literally⁶ explodes.”

The light pulse comes from a low-powered laser. It has less power than a laser pointer. It shines on a very tiny particle called the hemozoin, which is produced by the malaria parasite once it has infected red blood cells. Hemozoin crystals are not found in red cells that are not infected with malaria.

As the crystals are heated by the laser, they create small bubbles inside infected cells. Dr. Lopotko says the bubbles explode, and then make a sound that scientists can hear and count.

“You can detect just (a) few infected cells by a million normal cells.”

Dr. Lopotko says when researchers tested the device it was never wrong, and it was able to find malaria infection early, when treatment is very important.

The device can be carried, and uses batteries. It costs about $10,000 to $20,000 to make, but Dr. Lopotko says considering the number of people it can test, that is not a lot of money.

“Each device will be capable to screen more than 200,000 people per year. So the cost of analysis for each patient will be less than 50 cents.”

People without medical training can use the device to discover whether people are 

?infected with malaria.

Dr. Lopotko says the light beam used by the device is safe. Researchers will now test the device at a hospital in Houston that cares for patients infected with malaria. If those tests are successful, researchers will test the device throughout the world this year.

An article describing the malaria detection device was published in the journal Proceedings⁷ of the National Academy of Sciences.

I’m Christopher Cruise.

And I’m Steve Ember. You are listening to As It Is from VOA Learning English.

FDA Investigates Antibacterial Soaps

One of the best ways to avoid getting sick is washing your hands with soap and water. It has been shown effective in removing harmful germs and preventing their spread. But some soaps may be causing more harm than good. VOA’s Milagros Ardin has more.

 

Some companies have gone to great lengths to manufacture germ-killing⁸ products, like antibacterial soaps. In the United States, a federal agency recently called on the makers⁹ of such soaps to prove they are more effective than traditional soap and water. The Food and Drug Administration said the widespread use of antibacterial soap may be partly to blame for an increase in rising rates of drug-resistant bacteria.

Some evidence has suggested the products may even be harmful to your health.

The FDA has proposed that manufacturers be required to prove that antimicrobial soaps lower rates of disease more than other soaps. It also would require the companies to show how these cleansers do more good than harm. 

FDA officials estimate there are about 2,000 antimicrobial soaps on the market. People may think such products do a better job protecting them from getting sick. However, some studies suggest long-term use of the products can affect hormone¹⁰ levels and may be linked to cancer.

The Natural Resources Defense¹¹ Council has taken legal action against the FDA for letting companies use the chemicals triclosan and triclocarban in soaps. Mae Wu is a lawyer with the group.

"I think it’s a great first step!"

But for soap industry representatives say they do not understand the FDA proposal. In a statement, the Personal Care Products Council says it has already given “in-depth data” to the government. It says the information shows that antibacterial soaps are more effective in killing germs when compared with non-antibacterial soap. It also says the soaps do not add to resistance of antibiotic¹² drugs.

Sandra Kweder is the deputy director of the FDA. She says her agency’s move is an attempt to learn the benefits of using antibacterial products and their possible risks. If the proposed rule is approved, soap manufacturers would have to carry out studies showing their products are safe and more effective than plain soap.

If approved, Ms. Kweder expects the rule would take effect in 2016.

I’m Milagros Ardin.

1 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

2 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

3 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

4 parasites   

寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫

参考例句：

• These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的，而与寄生虫无关。
• Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。

5 wavelength   

n.波长

参考例句：

• The authorities were unable to jam this wavelength.当局无法干扰这一波长。
• Radio One has broadcast on this wavelength for years.广播1台已经用这个波长广播多年了。

6 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

7 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

8 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。

9 makers   

n.制造者，制造商（maker的复数形式）

参考例句：

• The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
• The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》

10 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

11 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

12 antibiotic   

adj.抗菌的；n.抗生素

参考例句：

• The doctor said that I should take some antibiotic.医生说我应该服些用抗生素。
• Antibiotic can be used against infection.抗菌素可以用来防止感染。