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From VOA Learning English, |
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this is the Health Report. |
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Researchers have developed a medical device |
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which they say can find malaria infections in the human body. |
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The laser beam scanner is the first device |
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that can find the sometimes deadly disease |
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without going inside the body. |
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The test is painless, does not need blood from a person, |
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and appears to be right every time it is done. |
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At the present time, |
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a trained medical worker needs costly equipment, |
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a person's blood and a lot of time to know |
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if a person has been infected with malaria. |
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Trained workers, equipment and time |
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are not always available in poor parts of the world. |
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The newly developed device only needs a person |
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to place a finger on a laser device. |
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Doctor Dmitri Lopotko is a researcher |
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at the department of biochemistry and cell biology |
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at Rice University in Houston, Texas. |
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"We shine a very short light pulse through the skin. |
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And this light pulse is absorbed only by malaria parasites |
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because of the wavelength we use. |
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And in response to this short light pulse, |
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the parasite literally explodes," he said. |
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The light pulse comes from a low-powered laser. |
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It has less power than a laser point. |
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It shines on a very tiny particle called the hemozoin |
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once it has infected red blood cells. |
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Hemozoin crystals are not found in red cells |
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that are not infected with malaria. |
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As the crystals are heated by the laser, |
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they create small bubbles inside infected cells. |
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Doctor Lopotko says the bubbles exploded, |
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and then make a sound that scientists can hear and count. |
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"You can detect just a few infected cells |
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in a million normal cells," he said. |
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Doctor Lopotko says when researchers tested the device, |
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it was never wrong. |
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And it was able to find malaria infection early |
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when treatment is very important. |
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The device can be carried and uses its batteries. |
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It costs about 10,000 to 20,000 dollars to make. |
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But Doctor Lopotko says |
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considering the number of people it can test, |
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that is not a lot of money. |
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"Each device will be capable to screen more than 200,000 people per year. |
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So the cost of analysis for each patient |
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will be less than 50 cents," he said. |
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People without medical training can use the device |
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to discover whether people are infected with malaria. |
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Doctor Lopotko says the light beam used by the device is safe. |
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Researchers will now test the device at a hospital in Houston |
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that cares for patients infected with malaria. |
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If those tests are successful, |
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researchers will test the device throughout the world this year. |
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An article describing the malaria detection device |
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was published in the journal |
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Proceedings of the National Academy of Sciences. |
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And that's the VOA Learning English Health Report. |
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I'm Christopher Cruise. |
