1918年的流感病毒基因源代码可能帮助人类抗击禽流感

1918 Flu's Genetic¹ Code May Help Fight Bird Flu

1918年的流感病毒基因源代码可能帮助人类抗击禽流感

 

It was the 20th century's greatest plague. Estimates of the 1918-1919 flu death toll² range from 20 million to 50 million, more than died in the war that had just preceded it.

 

The head of the U.S. government's disease tracking agency, Julie Gerberding of the Centers for Disease Control, says hardest hit were the young and productive between 20 and 40 years old.

 

Julie Gerberding: The 1918 influenza³ virus that caused such global disease spread very rapidly, particularly among healthy people, was very, very virulent⁴, and certainly circled the globe in record time.

 

U.S. government and private scientists have now finished a 10-year project to determine the virus' genetic makeup⁵. They recreated a live virus in a high-security laboratory at the Centers for Disease Control (CDC) by combining fragments from the organism's eight genes⁶.

 

Researcher Jeffrey Taubenberger of the Armed Forces Pathology Institute says the genetic scraps⁷ were gathered from well preserved lung tissue samples taken from victims during autopsies⁸ 87 years ago or, in one case, from a victim exhumed¹⁰ from Alaskan permafrost.

 

Jeffrey Taubenberger: Because influenza viruses were not known to exist in 1918, there were no isolates¹¹ made of this strain of the virus, and so there was actually no way for medical scientists to directly study this influenza virus.

 

The scientists tested the virus by inserting it into mice, chicken embryos¹³, and human lung cells. They found that by substituting genes from other flu viruses, they could make it less lethal¹⁴.

 

The research, published in the weekly journals Science and Nature, shows that the 1918 flu virus is more closely related to bird flus than human flus. It has several of the same genetic mutations found in the bird flu strain now spreading in Asia, mutations believed to help the virus replicate¹⁶ more efficiently¹⁷.

 

Mr. Taubenberger says this reveals that bird flu viruses can cause serious human infection without first combining with a strain already adapted to people. Some experts have said that effective human transmission might require combination with a human flu.

 

Jeffrey Taubenberger: We now think that the 1918 virus was an entirely¹⁸ avian-like virus that adapted to humans, it is a different situation than the last two pandemics we had, the Asian flu in 1957 and the Hong Kong flu in 1968, which are mixtures in which a human-adapted influenza virus acquired two or three new genes from an avian influenza source. So it suggests that pandemics can form in more than one way, and this is a very important point.

 

He says it also suggests that the current Asian bird flu, known by its scientific designation H5N1, could evolve into a human killer¹⁹ with just a few more mutations that allow it to jump more efficiently among people.

 

Jeffrey Taubenberger: It suggests to us the possibility that these H5 viruses are actually being exposed to some human adaptive pressures and that they might be acquiring some of these same changes. In a sense, they might be going down a similar path that ultimately led to 1918.

 

Mr. Taubenberger says if researchers can identify virus components²⁰ that are important in the process of adapting to humans, they could make a list of molecules²² to look for in emerging bird flus that threaten people.

 

Dr. Gerberding of the Centers for Disease Control says the work will allow new medical therapies to target those molecules.

 

Julie Gerberding: It is revealing to us some of the secrets that will help us predict and prepare for the next pandemic.

 

Dr. Gerberding says it is comforting to know that the 1918 virus, now that it has been reconstructed, is susceptible²³ to a new vaccine²⁴ U.S. researchers have developed against bird flu. This means it should work against the bird flu, too, if production can be expanded should a pandemic occur.

 

David McAlary, VOA news, Washington.

 

注释：

plague [plei^] n. 瘟疫，灾祸

virulent [5virulEnt] adj. 急性的，致死的（病毒、疾病）

genetic [dVi5netik] adj. 起源的

autopsy²⁵ [5C:tEpsi] n. （为查明死因而做的）尸体解剖，验尸

exhume⁹ [eks5hju:m] vt. 掘出，发掘

permafrost [5pE:mEfrRst] n. 冰冻层

embryo¹² [5embriEu] n. 胚胎

lethal [5li:WEl] adj. 致命的

mutation¹⁵ [mju(:)5teiFEn] n. 变化，突变

replicate [5replikit] v. 复制

designation [7dezi^5neiFEn] n. 名称

molecule²¹ [5mRlikju:l] n. 分子

therapy [5WerEpi] n. 疗法，治疗

1 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。

2 toll   

n.过路(桥)费；损失，伤亡人数；v.敲(钟)

参考例句：

• The hailstone took a heavy toll of the crops in our village last night.昨晚那场冰雹损坏了我们村的庄稼。
• The war took a heavy toll of human life.这次战争夺去了许多人的生命。

3 influenza   

n.流行性感冒，流感

参考例句：

• They took steps to prevent the spread of influenza.他们采取措施
• Influenza is an infectious disease.流感是一种传染病。

4 virulent   

adj.有毒的，有恶意的，充满敌意的

参考例句：

• She is very virulent about her former employer.她对她过去的老板恨之入骨。
• I stood up for her despite the virulent criticism.尽管她遭到恶毒的批评，我还是维护她。

5 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

6 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

7 scraps   

油渣

参考例句：

• Don't litter up the floor with scraps of paper. 不要在地板上乱扔纸屑。
• A patchwork quilt is a good way of using up scraps of material. 做杂拼花布棉被是利用零碎布料的好办法。

8 autopsies   

n.尸体解剖( autopsy的名词复数 )；验尸；现场验证；实地观察

参考例句：

• Autopsies cannot be performed and thus no recent histological examinations have been reported. 不能进行尸体解剖，因此没有新近的组织学检查的报道。 来自辞典例句
• I told you to supervise autopsies, not to set up a lot of fancy rules. 我叫你监督解剖室，不是去制定一些空想的规定。 来自辞典例句

9 exhume   

v.掘出，挖掘

参考例句：

• His remains have been exhumed from a cemetery in Queens,New York City.他的遗体被从纽约市皇后区的墓地里挖了出来。
• When the police exhume the corpse,they discover trace of poison in it.警方掘出尸体，发现有中毒的痕迹。

10 exhumed   

v.挖出，发掘出( exhume的过去式和过去分词 )

参考例句：

• Marie Curie's remains were exhumed and interred in the Pantheon. 玛丽·居里的遗体被移出葬在先贤祠中。 来自《简明英汉词典》
• His remains have been exhumed from a cemetery in Queens, New York City. 他的遗体被从纽约市皇后区的墓地里挖了出来。 来自辞典例句

11 isolates   

v.使隔离( isolate的第三人称单数 )；将…剔出（以便看清和单独处理）；使（某物质、细胞等）分离；使离析

参考例句：

• The transformer isolates the transistors with regard to d-c bias voltage. 变压器可在两个晶体管之间隔离直流偏压。 来自辞典例句
• In regions with certain isolates of TRV, spraining is more prominent. 在具有TRV某些分离物的地区，坏死是比较显著的。 来自辞典例句

12 embryo   

n.胚胎，萌芽的事物

参考例句：

• They are engaging in an embryo research.他们正在进行一项胚胎研究。
• The project was barely in embryo.该计划只是个雏形。

13 embryos   

n.晶胚；胚，胚胎( embryo的名词复数 )

参考例句：

• Somatic cells of angiosperms enter a regenerative phase and behave like embryos. 被子植物体细胞进入一个生殖阶段，而且其行为象胚。 来自辞典例句
• Evolution can explain why human embryos look like gilled fishes. 进化论能够解释为什么人类的胚胎看起来象除去了内脏的鱼一样。 来自辞典例句

14 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

15 mutation   

n.变化，变异，转变

参考例句：

• People who have this mutation need less sleep than others.有这种突变的人需要的睡眠比其他人少。
• So far the discussion has centered entirely around mutation in the strict sense.到目前为止，严格来讲，讨论完全集中于围绕突变问题上。

16 replicate   

v.折叠，复制，模写；n.同样的样品；adj.转折的

参考例句：

• The DNA of chromatin must replicate before cell division.染色质DNA在细胞分裂之前必须复制。
• It is also easy to replicate,as the next subsection explains.就像下一个小节详细说明的那样，它还可以被轻易的复制。

17 efficiently   

adv.高效率地，有能力地

参考例句：

• The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
• Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。

18 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

19 killer   

n.杀人者，杀人犯，杀手，屠杀者

参考例句：

• Heart attacks have become Britain's No.1 killer disease.心脏病已成为英国的头号致命疾病。
• The bulk of the evidence points to him as her killer.大量证据证明是他杀死她的。

20 components   

（机器、设备等的）构成要素，零件，成分； 成分( component的名词复数 )； [物理化学]组分； [数学]分量； （混合物的）组成部分

参考例句：

• the components of a machine 机器部件
• Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。

21 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

22 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

23 susceptible   

adj.过敏的，敏感的；易动感情的，易受感动的

参考例句：

• Children are more susceptible than adults.孩子比成人易受感动。
• We are all susceptible to advertising.我们都易受广告的影响。

24 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。

25 autopsy   

n.尸体解剖；尸检

参考例句：

• They're carrying out an autopsy on the victim.他们正在给受害者验尸。
• A hemorrhagic gut was the predominant lesion at autopsy.尸检的主要发现是肠出血。