2007年VOA标准英语-US Scientists Make Important Discovery in Battl

By Zulima Palacio
Washington
14 September 2007
 

University scientists in the United States have taken what they say is an important step in the effort to end malaria¹.  At Johns Hopkins Malaria Research Institute, scholars recently identified a sugar in mosquitoes that helps explain, for the first time, the  mechanism² of the malaria parasite³ invasion.  The finding could be a key element for a vaccine⁴ development in the fight against malaria.  Producer Zulima Palacio spoke⁵ with the authors of the research and files this report.  Carol Pearson narrates⁶ it.

Malaria is spread by mosquitoes

"I am removing the males only, because the males are not important to our research work.  Males do not blood feed, they feed on sugar only," says researcher Rhoel Ramos Ding-lasan. He is dissecting⁷ the type of mosquito that transmits the malaria parasite that kills about three million people each year around the world.  Experts report the understanding and control of the malaria parasite is one of the most serious scientific challenges of all time.

This week, scientists at the Johns Hopkins Malaria Research Institute announced they identified a sugar in mosquitoes that the malaria-causing parasite [Plasmodium falciparum] needs.  The sugar is essential in the parasite's movement within the midgut section of a mosquito's body.

"This is the mosquito gut⁸, filled with blood," demonstrates Professor Marcelo Jacobs-Lorena, the senior author of the research.  He says that by stopping the production of that sugar, the parasite dies. "The second step, which was a definite proof, was to -- by genetic¹⁰ means -- interrupt sugar production.  So we infected those impaired¹¹ mosquitoes with the parasite and we found that, indeed, the parasite was unable to traverse the midgut."

But the scientists say it is difficult to treat the mosquitoes in nature.  They suggest a human vaccination¹² with antibodies that would block sugar production in the mosquito.  When a mosquito feeds on human blood, it would ingest the antibody.

The new finding brings scientists one-step closer to developing effective malaria vaccines¹³.

Jacobs-Lorena adds,"The best hope we have is that we have a combination of transmission blocking vaccine that the antibody works in the mosquito stage, combined with infection blocking, so that people are protected."

Now 20 years into his work, Jacobs-Lorena says it will take 10 to 15 more years to find practical applications.  Still, he says this new study -- along with research on mosquito gene⁹ modication -- puts scientists closer every day to eradicate¹⁴ malaria.

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 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

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 vaccine   

n.牛痘苗，疫苗；adj.牛痘的，疫苗的

参考例句：

• The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
• She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

5 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

6 narrates   

v.故事( narrate的第三人称单数 )

参考例句：

• It narrates the unconstitutional acts of James II. 它历数了詹姆斯二世的违法行为。 来自辞典例句
• Chapter three narrates the economy activity which Jew return the Occident. 第三章讲述了犹太人重返西欧后的经济活动。 来自互联网

7 dissecting   

v.解剖（动物等）( dissect的现在分词 )；仔细分析或研究

参考例句：

• Another group was dissecting a new film showing locally. 另外一批人正在剖析城里上演的一部新电影。 来自辞典例句
• Probe into Dissecting Refraction Method Statics Processing under Complicated Surface Conditions. 不同地表条件下土壤侵蚀的坡度效应。 来自互联网

8 gut   

n.[pl.]胆量；内脏；adj.本能的；vt.取出内脏

参考例句：

• It is not always necessary to gut the fish prior to freezing.冷冻鱼之前并不总是需要先把内脏掏空。
• My immediate gut feeling was to refuse.我本能的直接反应是拒绝。

9 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

10 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

11 impaired   

adj.受损的；出毛病的；有（身体或智力）缺陷的v.损害，削弱( impair的过去式和过去分词 )

参考例句：

• Much reading has impaired his vision. 大量读书损害了他的视力。 来自《现代汉英综合大词典》
• His hearing is somewhat impaired. 他的听觉已受到一定程度的损害。 来自《现代汉英综合大词典》

12 vaccination   

n.接种疫苗，种痘

参考例句：

• Vaccination is a preventive against smallpox.种痘是预防天花的方法。
• Doctors suggest getting a tetanus vaccination every ten years.医生建议每十年注射一次破伤风疫苗。

13 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

14 eradicate   

v.根除，消灭，杜绝

参考例句：

• These insects are very difficult to eradicate.这些昆虫很难根除。
• They are already battling to eradicate illnesses such as malaria and tetanus.他们已经在努力消灭疟疾、破伤风等疾病。