Stem-cell therapies

　　干细胞治疗

　　Prometheus unbound

　　普罗米修斯自由了

　　Researchers have yet to realise the old dream ofregenerating organs. But they are getting closer

　　亘古以来，器官再生便是人类的夙愿。如今研究人员虽然还未真正实现，但成功的脚步已经越来越近

　　PROMETHEUS, a Titan bound to a rock by Zeus, endured the daily torture of an eaglefeasting on his liver, only to have the organ regrow each night.

　　在希腊神话之中，提坦普罗米修斯被宙斯束缚在一块巨石之上，白天忍受着老鹰啄食他的肝脏，夜晚他的肝脏却又总会再次生长。

　　Compared with this spectacle, a video on the website of Nature this week seems decidedlydull.

　　与生动的故事情节相比，本周《自然》网站上的一段视频就显得如此枯燥。

　　It shows a collection of pink dots consolidating into a darker central glob.

　　这段视频向世人展示了无数粉红色的小点向中心聚拢，成为一个颜色更深的团状物的过程。

　　But something titanic is indeed happening.

　　但这正是普罗米修斯自由的曙光。

　　The pink dots are stem cells, and thevideo shows the development of a liver bud, something which can go on to look and act likea liver.

　　那些粉红色的小点就是干细胞，而视频显示的正是肝芽生长的过程，并且这个肝芽可以进一步发育为，无论是外表还是功能都与肝脏类似的组织。

　　Takanori Takebe and Hideki Taniguchi of Yokohama City University, in Japan, who made thevideo, have created working human-liver tissue.

　　日本横滨市立大学的武部孝则和谷口英机拍摄了这段视频，这次他们培养出了具有功能性的人类肝脏组织。

　　Researchers have long dreamed that stem cells might be used to repair or replacedamaged tissue, an aspiration known as regenerative medicine.

　　研究人员长期以来都设想干细胞能够用来修复或替换受损组织，该研究领域则被冠名为再生医学。

　　Embryonic stem cells, in particular, are pluripotent, meaning they are able to become anyother type of cell.

　　多能的胚胎干细胞被再生医学家们寄予厚望，所谓多能就意味着这些干细胞可以分化出多种其他类型的细胞。

　　And it is now possible to induce pluripotency in cells that have not come from embryos, thuscircumventing the ethical minefield previously associated with obtaining them.

　　现在的技术已经可以在非胚胎细胞中诱导细胞的多能性，这样就可以绕过之前直接使用胚胎细胞时所引发的伦理争议。

　　Last year Shinya Yamanaka of Kyoto University won a Nobel prize for the invention ofinduced pluripotency.

　　日本京都大学的山中伸弥由于成功诱导细胞的多能性而于去年荣获诺贝尔奖。

　　He had shown how four signal proteins can reprogram adult cells into a pluripotent state.

　　他公开发表了借助四种信号蛋白，重组成人细胞并使其具有多能性的实验过程。

　　Beside dealing with the ethical problems of embryonic cells, Dr Yamanaka s inducedpluripotent stem cells allowat least in theorya treatment to be created from a patient sown body.

　　除了成功躲开了胚胎细胞的伦理问题，山中博士发明的诱导多能干细胞，使得再生医学可以从患者体内提取细胞进行再生治疗。

　　This would have his own genetic make up and would thus not attract the attention of hisimmune system.

　　这样就可以取得患者自身的基因组合，避免了患者免疫系统的排异反应。

　　Realising such treatments has been fiendishly difficult.

　　要真正实现这种干细胞治疗仍然困难重重，

　　But Dr Takebe s paper in Nature is one of several signs that the Promethean dream is slowlycoming to life.

　　但是武部博士发表于《自然》的论文则是人类又一次向解放普罗米修斯迈出了坚实的一步。

　　Budding hope

　　星星之火

　　Clinical trials of pluripotent cells are already happening, though they hark back to the dayswhen only cells derived from embryos were available.

　　多能细胞的临床试验其实早已开始进行，只是这种多能细胞还是由胚胎干细胞所培养。

　　An American firm called Advanced Cell Technology is using them to treat maculardegeneration, a cause of blindness.

　　美国先进细胞技术公司正运用多能细胞治疗可能致盲的黄斑变性。

　　Last year it reported promising results in two patients and Gary Rabin, the firm s boss, saystests continue.

　　去年该公司报告了两例有望好转的临床病患，公司老总加里拉宾也表示，试验仍会继续。

　　Even if this specific approach works, though, it is likely to be overtaken by iPS technology.

　　不过，即使这一临床试验终获成功，也有可能会被iPS技术所取代。

　　The Japanese, not surprisingly, are in the lead.

　　日本在iPS技术方面无疑领先于世界其他各国。

　　Soon, the country s health ministry is expected to approve the first clinical trial of iPS cells,also for macular degeneration.

　　该国卫生部应该不久便会批准iPS细胞的第一例临床试验，同样也是治疗黄斑变性。

　　But ACT is not far behind.

　　然而ACT也并未脱离战队，

　　It hopes to begin a trial of platelets made from iPS cells.

　　该公司希望开始一项iPS细胞培养血小板的试验。

　　And other firms want to treat everything from Parkinson s disease to glaucoma to multiplesclerosis.

　　还有些公司则希望透过iPS技术治疗其他疾病，包括帕金森病、青光眼、多发性硬化等。

　　Academia is pushing ahead as well.

　　学术界则正在进一步地研究iPS技术。

　　Inspired by Dr Yamanaka s work, people are looking for other shortcuts to pluripotency.

　　受到山中教授研究成果的启发，人们纷纷开始探究诱导细胞多能性更为便捷的其他途径。

　　Marius Wernig of Stanford University, for instance, has worked out how to use three proteinsto turn connective-tissue cells into neurons.

　　斯坦福大学的马吕斯维米格就发现了使用三种蛋白质，将结缔组织细胞转化为神经细胞的方法。

　　Deepak Srivastava of the University of California, San Francisco, meanwhile, has shown howto convert connective tissue into heart cells.

　　加州大学旧金山分校的迪帕克司里瓦斯德瓦则发表了将结缔组织转化为心肌细胞的过程。

　　Other research is going beyond simple cell cultures.

　　还有一些研究就没有局限于简单的细胞培养领域。左使良树任职于神户的理化研究所发育生物学中心。

　　In 2011 Yoshiki Sasai of the RIKEN Centre for Developmental Biology, in Kobe, showed howmouse embryonic stem cells, if mixed with a few appropriate growth factors, quickly form athree-dimensional cluster made of the precursor cells to neurons.

　　他于2011年发表论文，阐述了老鼠胚胎干细胞在给予一些适当的生长因子后，快速形成一个三维立体簇集物的过程。

　　This cluster then turns into something resembling the back of an eye.

　　而这种簇集物由多种细胞构成，并进而发育成一种类似于眼底结构的组织。

　　Last year Dr Sasai repeated the trick with human cells.

　　去年左使博士使用人类细胞再次重复了这一实验过程。

　　The dream is to make a complex organ from scratch.

　　人们的梦想就是从无到有地创造出一个复杂的器官。

　　With this in mind researchers at Wake Forest University in North Carolina have used athree-dimensional printer to produce an artificial kidney using immature kidney cells.

　　为了实现这个梦想，北卡罗来纳州维克森林大学的研究员们使用三维打印技术，用不成熟的肾脏细胞做出了一个人造肾脏。

　　But if such organs are to work in people, they will need blood vessels to deliver oxygen andnutrients.

　　不过要让这样的肾脏在人体内正常工作，其中还是缺少了用于输送氧气和营养物质的血管。

　　The way to do that might, paradoxically, be for scientists to do less. Instead of making thewhole organ in a laboratory, they might create a less-developed form, as Dr Sasai did withhis proto-retina, and then leave the rest of the work to the body.

　　如果真要实现这个梦想，科学家可能用不着在肾脏中再造血管这听起来可能有些自相矛盾他们其实不必在实验室中造出完整的人体器官。科学家可以先造出还没发育完全的器官试样，然后在活体体内完成剩下的研究工作。

　　This is what Dr Takebe has done with his liver buds.

　　武部博士的肝芽生长研究正是遵照这样的器官再造思路而完成的。

　　He coaxed some iPS cells into becoming liver endodermal cells.

　　他小心地将一些iPS细胞导入合适的肝脏内胚层细胞。

　　He then cultured them with two other cell types: endothelial cells, which make up the innerlinings of blood vessels, that were derived from umbilical cord; and mesenchymal stem cells,derived from bone marrow, which can differentiate into several kinds of cells, though not asmany as pluripotent cells.

　　然后将这些肝脏内胚层细胞与其他两种细胞一起培养。一种是取自脐带的内皮细胞，这种细胞构成了血管内层;另一种细胞是取自骨髓的间充质干细胞，这种细胞可以分化成多种细胞类型。

　　Cultures without mesenchymal stem cells failed to form a cluster.

　　实验证明，如果培养过程中缺少间充质干细胞，就不会形成簇集物;

　　Those without endothelial cells failed to create a network of blood vessels.

　　而如果没有内皮细胞，就无法形成血管网络。

　　But together, the three types of cell, with little additional prodding, formed a bud withintwo days.

　　只有将肝脏内胚层细胞与这两者结合，并配合少量的其他刺激，才最终能在两天内形成肝芽。

　　At six days this bud was expressing genes known to be early markers of the liver.

　　到了第六天，肝芽开始表达一些在肝脏早期形成阶段具有标志性的基因。

　　And when Dr Takebe implanted such buds into the brains of mice whose immune systemshad been disabled to prevent rejection, he observed that they connected with the mouse sblood system within two days.

　　随后，武部博士将这些肝芽结构植入一些丧失免疫能力的老鼠的脑中，这样老鼠就不会对肝芽组织形成排斥反应。武部博士发现，两天内肝芽结构就与这些老鼠脑中的血液循环系统相互融合了。

　　After two months the buds not only looked like liver, they acted like it.

　　两个月后，肝芽结构除了看上去像肝脏外，也具有了肝脏的生理功能他们产生出了肝脏独有的蛋白质。

　　They produced liver-specific proteins. And if Dr Takebe transplanted them to their host sabdominal cavity, having first caused the animal s real liver to fail, they often kept the mousealive when an animal without the transplant would have died.

　　然后武部博士又将这些肝芽结构移植到了相应老鼠的腹腔中，起初肝芽结构会破坏老鼠体内自身的肝脏，但是接着很多老鼠并没有死亡。

　　Translating this work into a way of growing new livers for people whose old ones havestopped working will take time.

　　诚然，要将这个过程在人类身上临床试验仍需时日。

　　But it is a big step forward.

　　但在老鼠体内的实验已是继往开来的重要一步。

　　After years of promise, regenerative medicine may be coming close to delivering.

　　在人们年复一年的期盼中，再生医疗终会有实现梦想的那一天。

　　词语解释

　　1.bound to 束缚于

　　This dichotomy is bound to have social andpolitical consequences.

　　这种截然不同的情况一定会带来社会和政治的影响。

　　Any such far-reaching intervention is bound toleave clues in the body.

　　这些影响深远的生理干涉一定会在身体上留下痕迹。

　　2.use to 过去常常

　　Below are different strategies you can use to help you deal with each of these negativeemotions.

　　下面介绍了一些不同的方法可以用来帮助您处理每一种负面情绪。

　　Mining has led to water polluted by mercury which miners use to separate the metal fromriver sediment.

　　但开采者常用来从河沙中分离黄金的水银也导致了河水的污染。

　　3.associate with 与交往， 联系;交接

　　The date and time to associate with the type library.

　　与该类型库相关联的日期和时间。

　　Create a container control designer class to associate with the custom control.

　　创建容器控件设计器类，并将其与自定义控件关联。

　　4.derive from 由起源;取自

　　That includes the stem cells themselves, which derive from ur stem cells found inembryos.

　　而干细胞则是来自胚胎中的ur干细胞。

　　One answer is the indirect benefit that investors derive from addressing the economic risksof global warming.

　　答案之一是间接的好处，投资者从处理全球变暖的经济风险中得到好处。