VOA慢速英语2014 科学家研发PTSD血液测试

 

AS IT IS 2014-08-25 Scientists Developing Blood Test for PTSD

Post-Traumatic Stress Disorder¹ or PTSD is caused by a frightening event, either witnessed or experienced.  Signs of the disorder may include depression, bad dreams and severe nervousness.  Thoughts about the event may be uncontrollable.

Soldiers who have seen a lot of death and destruction in armed conflict, survivors² of natural disasters and rape³ victims often suffer from PTSD. 

Even with treatment, the brain disorder is difficult to cure.  But someday, a blood test may show if a person is threatened by PTSD or already suffers from it.  Researchers at Icahn School of Medicine at Mount Sinai in New York have identified a blood marker that appears linked to PTSD.

The researchers used rats and cat waste in their work.  They saw a pattern of gene⁴ activity involved in the operation of the stress hormone⁵ corticosterone in the brain tissue of the rats.  The activity took place after the rats smelled the urine of cats for 10 minutes.  The liquid waste was in cat litter, a material that lines a waste box for indoor cats. 

Loud noises caused the rats to show anxiety - fear - when they were tested.  And they were easily startled.  Then, the stressed rats were given corticosterone an hour after they smelled the cat litter.  The researchers found that one week after seeing the litter, the treated rats showed little interest and nervousness compared to untreated rats.

Icahn scientist Nikolaos Daskalakis said Swiss doctors noted⁶ that the hormone corticosterone calmed people who received it after a car accident.  He said the finding may lead to the development of a test for PTSD risk.  The test would measure what is called glucocorticoid receptor activity in the blood.  The receptors are genes⁷ that become "turned on" in the presence of stress.

Corticosterone is produced naturally by the body.  The hormone connects to the receptor and has a calming effect.  But in some rats and in some people, the pathway appears to be ineffective.  This puts them at higher risk for PTSD. 

Scientist Daskalakis says PTSD does not just affect the brain.  He says it involves the whole body.  He says this is why identifying common regulators is extremely important.  He also says more detailed⁸ studies in humans and in animals are needed in order to one day have a treatment.

1 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

2 survivors   

幸存者，残存者，生还者( survivor的名词复数 )

参考例句：

• The survivors were adrift in a lifeboat for six days. 幸存者在救生艇上漂流了六天。
• survivors clinging to a raft 紧紧抓住救生筏的幸存者

3 rape   

n.抢夺，掠夺，强奸；vt.掠夺，抢夺，强奸

参考例句：

• The rape of the countryside had a profound ravage on them.对乡村的掠夺给他们造成严重创伤。
• He was brought to court and charged with rape.他被带到法庭并被指控犯有强奸罪。

4 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。

5 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。

6 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

7 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

8 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。