文/By+Robert+Coontz+譯/兩袖清風
Cancer Immunotherapy1)
This therapy harnesses2) the immune system to battle tumors. Scientists have thought for decades that such an approach to cancer therapy should be possible, but it has been incredibly difficult to make it work. Now many oncologists3) say we have turned a corner4), because two different techniques are helping some patients. One involves antibodies that release a brake5) on T cells6), giving them the power to tackle tumors. Another involves genetically modifying an individual's T cells outside the body so that they are better able to target cancer, and then re-infusing7) them so they can do just that. We are still at the beginning of this story and only a very small proportion of cancer patients have received these therapies. But the results have been repeated at different centers and in different tumor types, giving doctors hope that immunotherapy for cancer may benefit more and more people in the future.
Cloning Human Stem Cells
After more than a decade of failures, researchers announced they had derived stem cells from cloned human embryos8). Such cells can develop into any of the body's cell types, and researchers hope to use them to study and treat diseases. Mice, pigs, dogs, and other animals have been cloned by the same technique used on Dolly the sheep9), but human cells have proved much trickier to work with. In 2013, a new recipe—including a dash of caffeine, which appears to stabilize key molecules in delicate10) human egg cells—solved the problem. Now researchers must determine how embryonic stem cells from the cloned embryos stack up against11) induced pluripotent stem cells12).
Cosmic Particle Accelerator Identified
Cosmic rays—high-energy protons13) and other particles from outer space—were first detected 100 years ago. Now researchers have finally nailed down14) solid evidence of where they come from. Theorists had long suspected that most are accelerated in the shock waves15) from massive exploding stars, or supernovae. If so, they reasoned, some of the particles must collide with atoms in space to produce subatomic particles called pions16), which would then decay17) into gamma rays. In 2013, the Fermi Gamma-Ray Space Telescope spotted the telltale18) pion-decay signature in the debris19) from two supernovae.
Newcomer to the Race to Harness Sunlight
A new breed of materials for solar cells burst into the limelight20) in 2013. Known as perovskites21), they are cheap, easy to make, and already capable of converting 15 percent of the energy in sunlight to electricity. While that remains below the efficiency of commercial silicon solar cells, perovskites are improving fast. One particularly promising feature is that they can be layered on top of silicon solar-cell material to harness a range of wavelengths that neither could capture alone.endprint
Genetic Microsurgery
A year-old gene-editing technique called CRISPR touched off an explosion of research in 2013. It's short for "clustered regularly interspaced short palindromic22) repeats": repetitive stretches of DNA that bacteria have evolved to combat predatory23) viruses by slicing up the viral24) genomes25). The "knife" is a protein called Cas9; in 2012, researchers showed they could use it as a scalpel26) to perform microsurgery on genes. In 2013, the new technology became red-hot, as more than a dozen teams wielded27) it to manipulate specific genes in mice, rats, bacteria, yeast, zebrafish, nematodes28), fruit flies, plants, and human cells, paving the way for understanding how these genes function and possibly harnessing them to improve health.
To Sleep, Perhaps to Clean
Scientists have long speculated that one of the functions of sleep is to restore and repair the brain, but whether this is a "core" purpose of sleep remains controversial. In 2013, researchers found direct experimental evidence that the mouse brain cleans itself during sleep, by expanding channels between neurons that allow an influx29) of cerebrospinal fluid30). The fluid flushes out detritus31) such as amyloid32) proteins, which accumulate as plaques33) in Alzheimer's disease, twice as fast when mice are sleeping as when they are awake.
癌癥免疫療法
這一療法利用人體免疫系統(tǒng)對抗腫瘤。數十年來,科學家們一直認為這種癌癥療法應該是可行的,只是該療法一直極難付諸實踐?,F在,很多腫瘤學家紛紛表示,這一研究已經取得里程碑式的進展,因為如今已有兩種不同的免疫療法可以幫助一些癌癥患者。一種方法是通過抗體減少T細胞的抑制因素,從而充分發(fā)揮T細胞的抗癌能力。另一種方法是通過對患者的T細胞進行體外基因改造,提高T細胞的抗癌能力,然后再將這些T細胞注入患者體內,從而發(fā)揮抗癌作用。癌癥免疫療法目前仍然處于起步階段,至今只有極少數癌癥患者接受過這類治療。不過,癌癥免疫療法的效果已在不同的治療中心和不同類型的腫瘤上得到反復證實,這給了醫(yī)生們一線希望——癌癥免疫療法將來或許能夠造福更多的患者。
人類干細胞的克隆
經歷十余年的失敗之后,研究人員宣布,他們從克隆的人類胚胎中提取出了干細胞。這些干細胞可以培育成人體內任一類型的細胞,研究人員希望能夠利用它們來研究和治療疾病。盡管人類早已運用克隆多莉羊的技術克隆出了小鼠、豬、狗以及其他一些動物,但事實證明克隆人體細胞更為棘手。2013年出現的一種新方法解決了這一難題,該方法中用到了少量咖啡因,而咖啡因似乎能穩(wěn)定脆弱的人類卵細胞中的核心分子?,F在,研究人員必須要確定的是,通過克隆胚胎獲得的胚胎干細胞和誘導性多能干細胞相比,兩者孰優(yōu)孰劣。
宇宙粒子“加速器”的發(fā)現
宇宙射線是指來自外太空的高能質子和其他粒子,于100年前首次被人類發(fā)現?,F在,研究人員終于找到了宇宙射線來源的有力證據。理論家們早就懷疑,大部分宇宙射線是經由大質量恒星爆炸(即超新星)產生的激波高速拋出的。如果確實如此,他們推斷,宇宙射線中的某些粒子肯定會跟太空中的原子發(fā)生碰撞,產生一種稱為“π介子”的亞原子粒子,繼而衰變成伽馬射線。2013年,費米伽馬射線太空望遠鏡在兩個超新星殘骸里發(fā)現了證明π介子衰變存在的特征。
太陽能利用領域喜添新成員
2013年,一種新型太陽能電池材料突然成為關注的焦點,這就是鈣鈦礦太陽能電池。 鈣鈦礦太陽能電池成本低廉,易于制造,目前已能夠將15%的太陽能轉換成電能。盡管該效能仍然低于商用硅太陽能電池,但鈣鈦礦太陽能電池發(fā)展迅猛,且具有一個十分有發(fā)展前景的特點,即可以將其鋪在硅太陽能電池材料上面,以此將兩者單獨使用時無法吸取的一段波長的太陽能轉化為電能。
基因“顯微外科手術”
2013年,問世僅一年的基因編輯技術CRISPR掀起了一股科研狂潮。CRISPR為“規(guī)律成簇間隔短回文重復序列”的縮略語,是指細菌進化而來的一段DNA重復序列,可通過切割病毒基因組的方式抵御攻擊性病毒。切割病毒基因組的這把“刀”是一種名叫Cas9的蛋白質。2012年,研究人員發(fā)現,他們可將Cas9蛋白質用作“手術刀”對基因進行顯微外科手術。2013年,這項新技術成為一個研究熱點,超過12個研究團隊利用該技術來操縱小鼠、老鼠、細菌、酵母、斑馬魚、線蟲、果蠅、植物和人類細胞的特定基因,為進一步了解這些基因的運作機制甚至利用這些基因來改善機體健康做好準備。endprint
大腦可能在利用睡眠進行“大掃除”
長期以來,科學家們一直猜測睡眠的作用之一是恢復和修復大腦機能,但對這是否為睡眠的“主要”目的這一問題尚存爭議。2013年,研究人員找到了直接的實驗證據,表明小鼠的大腦在睡眠期間能夠通過擴展神經元之間的通道,使大量腦脊髓液注入其中,以此進行自我清理。小鼠在睡眠時,其腦脊髓液會以兩倍于清醒時的速度清理掉神經元間通道內的殘余物,比如淀粉樣蛋白——這種蛋白一旦積聚,就會形成導致老年癡呆癥的噬斑。
1. immunotherapy [??mj?n???θ?r?p?] n.【醫(yī)】免疫療法
2. harness [?hɑ?n?s] vt. 利用(或控制)……以產生動力,利用
3. oncologist [???k?l?d??st] n. 腫瘤學家
4. turn a corner: 進入一個新的局面(階段、時期)
5. brake [bre?k] n. 起抑制作用的因素,約束
6. T cell: T細胞,一種多能干細胞,具有細胞免疫和免疫調節(jié)功能。
7. infuse [?n?fju?z] vt. 把……注入
8. embryo [?embri??] n. 胚胎
9. Dolly the sheep: 克隆羊多莉,是1996年英國科學家克隆成功的一頭母羊,標志著科學界克隆成就的一大飛躍。
10. delicate [?del?k?t] adj. 纖弱的
11. stack up against: 與……較量,爭勝負
12. induced pluripotent stem cell: 誘導性多能干細胞,指通過誘導重新編程技術將細胞轉變?yōu)轭愃婆咛ジ杉毎亩嗄芨杉毎?/p>
13. proton [?pr??t?n] n. 質子
14. nail down: 弄清;確定
15. shock wave: 激波,又稱沖擊波,是氣體、液體和固體介質中壓強、密度和溫度在波陣面上發(fā)生突躍變化的壓縮波。在超聲速流動、爆炸等過程中都會出現激波。
16. pion [?pa??n] n. π介子
17. decay [d??ke?] vi.【物】(放射性物質等)衰減,衰變
18. telltale [?telte?l] adj. 能證明(某事)存在的
19. debris [?debri?] n. (被毀物的)殘??;瓦礫
20. limelight [?la?mla?t] n. 公眾注意的中心
21. perovskite [p??r?vska?t] n. 鈣鈦礦
22. palindromic [?p?l?n'dr?m?k] adj. 回文結構的
23. predatory [?pred?tri] adj. (動物或其習性)以捕食其他動物為生的;掠奪(性)的
24. viral [?va?r?l] adj. 【醫(yī)】病毒(性)的;病毒引起的
25. genome [?d?i?n??m]
n.【生】基因組,染色體組
26. scalpel [?sk?lp?l] n. 解剖刀,一種外科手術刀
27. wield [wi?ld] vt. 揮;操;使用
28. nematode [?nem?t??d] n.【動】線蟲
29. influx [??nfl?ks] n. 流入,注入;涌進
30. cerebrospinal fluid: 腦脊(髓)液
31. detritus [d??tra?t?s] n. 殘余物
32. amyloid [??m??l??d] adj. 淀粉狀的
33. plaque [pl?k] n.【醫(yī)】血小板;斑。這里指大腦組織中的噬斑。endprint