美国国家公共电台 NPR Scientists Restore Some Function In The Brains Of Dead Pigs

 

AUDIE CORNISH, HOST:

Now we turn to a startling development in the world of science. The brains of dead pigs have been partially¹ revived in the lab hours after the animals were killed in a slaughterhouse. NPR's Nell Greenfieldboyce reports that scientists and ethicists alike are grappling with the implications.

NELL GREENFIELDBOYCE, BYLINE²: Brains are supersensitive to a lack of oxygen, and it's long been thought that oxygen starvation quickly leads to irreversible cell death. But some clues suggested the story isn't this simple.

Nenad Sestan is a neuroscientist at Yale University.

NENAD SESTAN: You can harvest cells from post-mortem brain hours after death and, basically, you can be carbon viable³ cells. You can study them.

GREENFIELDBOYCE: By keeping them alive in a lab dish.

SESTAN: The problem was that once you do that, you are losing the 3D organization of the brain.

GREENFIELDBOYCE: That limits what you can study about brains and brain injury. So he and some colleagues at Yale spent the last six years developing a new approach.

Stefano Daniele says they went to a local pork processing plant. They bought pig heads and immediately began their process.

STEFANO DANIELE: We've come up with a brain-flushing procedure to not only clear the residual⁴ blood that remains⁵ within the brain but also to cool the brain down.

GREENFIELDBOYCE: Back at the lab, the researchers took the brains and put them in a special chamber⁶. They hooked up key blood vessels⁷ to a device that pumped in a chemical cocktail⁸. This solution brought in oxygen, nutrients⁹ and various injury-repairing ingredients about four hours after the pigs were killed.

DANIELE: This really was a shot-in-the-dark project, and we had no preconceived notion of whether or not this could work.

GREENFIELDBOYCE: Well, it did. In the journal Nature, they say six hours of being hooked up to the device reduced cell death, prevented tissue degradation¹⁰ and restored some cellular¹¹ functions. But - and this is important - they saw no signs of the kind of organized electrical activity that's associated with consciousness.

Stephen Latham is a Yale bioethicist who worked with the team.

STEPHEN LATHAM: It was never a goal of the research to try to restore consciousness to the pig brain. In fact, it was something that the researchers were actively¹² worried about.

GREENFIELDBOYCE: He says the scientists monitored electrical activity and would've administered anesthesia if they saw any hint of consciousness.

What's more, the solution pumped into the brains contained a drug that inhibits¹³ brain cell activity. But if this drug was removed, could signs of consciousness emerge? And how would that kind of research even be regulated?

LATHAM: No one has ever thought about how to deal with this question of what if we induced consciousness in a brain that's not connected to any living animal? So nobody has jurisdiction¹⁴ over that.

GREENFIELDBOYCE: For example, animal welfare regulations didn't apply to this study in part because the pigs were used as food and in part because they were dead.

NITA FARAHANY: It's a dead animal. It's not subject to any research protections because you wouldn't expect that it would suffer from any pain or distress¹⁵ or, you know, need to be thought about in terms of humane¹⁶ care.

GREENFIELDBOYCE: Nita Farahany studies the ethics¹⁷ of new technologies at Duke University. She serves on a neuroethics group convened¹⁸ by the National Institutes of Health, which funded this work.

FARAHANY: My initial reaction was pretty shocked. You know, it's a ground-breaking discovery.

GREENFIELDBOYCE: She says it challenges our existing beliefs about what's alive and what's dead. And while this experiment produced no signs of the brain activity associated with consciousness...

FARAHANY: The potential is there. And we have to answer the questions of whether and, if so, how much of other kinds of activity can be restored to the brain and what that means.

GREENFIELDBOYCE: She says we still need to figure out the ethical¹⁹ path forward for this new way of keeping brains going in the lab.

Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF ELEANOR FRIEDBERGER'S "HE DIDN'T MENTION HIS MOTHER")

1 partially   

adv.部分地，从某些方面讲

参考例句：

• The door was partially concealed by the drapes.门有一部分被门帘遮住了。
• The police managed to restore calm and the curfew was partially lifted.警方设法恢复了平静，宵禁部分解除。

2 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

3 viable   

adj.可行的，切实可行的，能活下去的

参考例句：

• The scheme is economically viable.这个计划从经济效益来看是可行的。
• The economy of the country is not viable.这个国家经济是难以维持的。

4 residual   

adj.复播复映追加时间；存留下来的，剩余的

参考例句：

• There are still a few residual problems with the computer program.电脑程序还有一些残留问题。
• The resulting residual chromatism is known as secondary spectrum.所得到的剩余色差叫做二次光谱。

5 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

6 chamber   

n.房间，寝室；会议厅；议院；会所

参考例句：

• For many,the dentist's surgery remains a torture chamber.对许多人来说，牙医的治疗室一直是间受刑室。
• The chamber was ablaze with light.会议厅里灯火辉煌。

7 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

8 cocktail   

n.鸡尾酒；餐前开胃小吃；混合物

参考例句：

• We invited some foreign friends for a cocktail party.我们邀请了一些外国朋友参加鸡尾酒会。
• At a cocktail party in Hollywood,I was introduced to Charlie Chaplin.在好莱坞的一次鸡尾酒会上，人家把我介绍给查理·卓别林。

9 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

10 degradation   

n.降级；低落；退化；陵削；降解；衰变

参考例句：

• There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。
• Gambling is always coupled with degradation.赌博总是与堕落相联系。

11 cellular   

adj.移动的；细胞的，由细胞组成的

参考例句：

• She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
• Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

12 actively   

adv.积极地，勤奋地

参考例句：

• During this period all the students were actively participating.在这节课中所有的学生都积极参加。
• We are actively intervening to settle a quarrel.我们正在积极调解争执。

13 inhibits   

阻止，抑制( inhibit的第三人称单数 )； 使拘束，使尴尬

参考例句：

• A small manufacturing sector inhibits growth in the economy. 制造业规模太小有碍经济增长。
• His bad English inhibits him from speaking freely. 他英语学得不好，这使他不能表达自如。

14 jurisdiction   

n.司法权，审判权，管辖权，控制权

参考例句：

• It doesn't lie within my jurisdiction to set you free.我无权将你释放。
• Changzhou is under the jurisdiction of Jiangsu Province.常州隶属江苏省。

15 distress   

n.苦恼，痛苦，不舒适；不幸；vt.使悲痛

参考例句：

• Nothing could alleviate his distress.什么都不能减轻他的痛苦。
• Please don't distress yourself.请你不要忧愁了。

16 humane   

adj.人道的，富有同情心的

参考例句：

• Is it humane to kill animals for food?宰杀牲畜来吃合乎人道吗？
• Their aim is for a more just and humane society.他们的目标是建立一个更加公正、博爱的社会。

17 ethics   

n.伦理学；伦理观，道德标准

参考例句：

• The ethics of his profession don't permit him to do that.他的职业道德不允许他那样做。
• Personal ethics and professional ethics sometimes conflict.个人道德和职业道德有时会相互抵触。

18 convened   

召开( convene的过去式 )； 召集； （为正式会议而）聚集； 集合

参考例句：

• The chairman convened the committee to put the issue to a vote. 主席召集委员们开会对这个问题进行表决。
• The governor convened his troops to put down the revolt. 总督召集他的部队去镇压叛乱。

19 ethical   

adj.伦理的，道德的，合乎道德的

参考例句：

• It is necessary to get the youth to have a high ethical concept.必须使青年具有高度的道德观念。
• It was a debate which aroused fervent ethical arguments.那是一场引发强烈的伦理道德争论的辩论。