- 用心翻譯每一天
聯系我們
全國統一服務熱線：
電話：021-58446796
公司QQ：732319580
郵箱：daisy.xu@easytranslation.com.cn
網址：m.jpgfs2012.com
地址：上海浦東金橋開發區金豫路700號6號樓1樓
Long Trips to Space Linked to Possible Brain Damage 在太空長期停留可能會導致腦損傷 Five space travelers had elevated levels of proteins in the blood often seen in people with head trauma and neurodegenerative diseases. 五位太空旅行者血液中的蛋白質含量增高。這種情況經常會出現在有頭部創傷和神經退化癥的病人當中。 Over the past several years, scientists have published research suggesting that people’s brains change after spending longer than a few months in space. These studies started because astronauts experienced issues like vision problems and swollen optic nerves upon returning to Earth after long missions. 在過去的數年里，科學家們所發表的研究論文表明，如果在太空中停留的時間超過數月，人的大腦就會發生改變。這些研究始于宇航員在太空中經過長時間停留并在返回地球后出現視力問題和視覺神經腫脹問題。 Researchers are now wondering whether these extended trips to space damage the brain. In a new study of five male cosmonauts (Russian astronauts), researchers looked at levels of different proteins in the blood that are often also seen in people with some sort of head trauma or brain disease. They found that on average, the cosmonauts had higher levels of some of the proteins in the three weeks following the mission than before. 研究人員們目前正在思考長時間停留在太空是否會對大腦造成損傷。在一項新的關于5名男性航天員（俄羅斯航天員）的研究中，研究人員觀察了他們血液中的各種蛋白質的含量。血液中的這些蛋白質往往也會出現在存在某類頭部創傷或大腦疾病的人群中。研究人員發現，在太空任務結束后的三周內，宇航員血液中某些蛋白的含量要比去太空之前有所升高。 Cosmonaut：航天員 Dr. Donna Roberts, a neuroradiologist at the Medical University of South Carolina in Charleston who did not contribute to the new paper, said that more studies need to be done to determine if these changes are clinically significant, but that the new paper is “an example of the type of tests we need to start doing more of” to better understand the effects of the brain’s changes during long-duration spaceflight. Donna Roberts博士是查爾斯頓南卡羅萊納醫學院的一名神經放射學醫生，Donna Roberts并未參與新論文的發表。Roberts博士表示，要想了解這些變化是否具有臨床意義，還需要進行更多的研究。但是，新論文里的測試就屬于我們需要更多進行的測試，這些測試可以幫助我們更好地了解在長時間太空飛行過程中大腦變化的結果。 Neuroradiologist：神經放射學醫生 The effects of long-term space travel on humans 長時間太空旅行對人類的影響 For over twenty years, humans have been visiting the International Space Station, which orbits Earth more than 200 miles above the planet. A typical trip lasts about six months. The space station is in free fall around Earth, so people on the space station experience a state of near weightlessness. Such “microgravity” is thought to be the main cause of a number of changes the human body can experience while in spaceflight, including the loss of muscles and bone density. 在過去20多年的時間里，人類一直都會前往太空空間站。太空空間站在地球上空200多英里處圍繞地球旋轉。前往空間站通常需要大約6個月。空間站圍著地球進行慣性運動，因此空間站上的人們會體驗到一種接近失重感的狀態。這種微重力被認為是太空飛行中使人體發生變化的主要原因，包括肌肉和骨密度流失。 Orbit：沿軌道運行；圍繞…運動 In the last couple of years, brain imaging has also revealed a loss in volume of grey matter, which contains the cell bodies of neurons, and an increased volume of cerebrospinal fluid. Roberts, who uses imaging to study the effect of spaceflight on the brain, has published research showing that in some people who have had long missions on the ISS, their brain has moved up in their head towards the top of their skull, and cerebrospinal fluid occupies more space below and in the center of the brain. 在過去的數年里，大腦成像也顯示出大腦灰質的含量有所減少（灰質中含有神經元細胞體）以及腦脊液的含量有所增加。Roberts利用腦成像來研究太空飛行對大腦的影響并發表了研究論文。論文顯示，某些在國際空間站執行長期任務的宇航員的大腦會朝顱骨上方移動，因此腦脊液會在顱骨下方占據更多的空間并會位于大腦的中央。 But researchers don’t know what these brain changes might mean for people’s health and cognition. Dr. Peter zu Eulenburg, a co-first author of the new study, published online Oct. 11 in JAMA Neurology, said the previous studies raised questions: “Is there any damage to the brain? Is this really harmful for the cosmonauts?” 但是，研究人員還不清楚大腦的這些變化對人類健康和認知有哪些影響。Peter zu Eulenburg是新研究的第一合作作者，該項新研究于10月11日由JAMA neurology發布在網上。他表示，此前的研究提出了一些問題：“這些變化對大腦是否有損害？這些變化是否真的對宇航員有害？” Looking at blood for signs of brain damage 通過血液發現大腦損傷的跡象 To look for evidence of brain injuries, zu Eulenburg and his colleagues measured the levels of five different proteins in the blood of five male cosmonauts both before and after approximately six-month trips to the space station. 為了尋找大腦損傷的證據，zu Eulenburg和他的同事在五位宇航員前往空間站之前和前往空間站后大約6個月對他們血液中5種不同的蛋白質水平進行測量。 These proteins are biomarkers that “can tell us about the status of the brain without opening up the brain,” said Keisuke Kawata, a neuroscientist at Indiana University Bloomington. Kawata, who studies repetitive head impacts and did not contribute to the study, said that the best fluid for studying biomarkers is cerebrospinal fluid in the brain and spinal cord, but accessing it requires an invasive spinal tap. Drawing blood is much easier, and blood “is the second-best biological fluid to test the brain health,” he said. 這些蛋白質是生物標記物。這些生物標記物“可以讓我們在不用打開大腦的情況下了解到大腦的狀態”，Keisuke Kawata，印地安那大學伯明頓分校的一位神經科學家表示。研究重復性大腦影響的Kawata并未參與此項研究。他表示，研究生物標記物的最佳液體是大腦和腰椎中的腦脊液，但是對其進行評估需要進行侵入式的腰椎穿刺。抽血則要容易得多，而且血液也屬于“僅次于腦脊液的、衡量大腦是否健康的生物液體”，他表示。 spinal tap：腰椎穿刺 The biomarkers in the study can be used “to indirectly evaluate the extent of damage” due to neurodegeneration or a traumatic injury, said zu Eulenburg, who is a neurologist and professor of neuroimaging at the German Center for Vertigo and Balance Disorders. Neurofilament light chain, for example, is a structural protein that maintains neurons’ axons, which transmit signals to other neurons. 研究中的生物標記物可以用來“間接評估由于神經退變或創傷性損傷”所導致的受傷程度，zu Eulenburg表示。Zu Eulenburg是眩暈和平衡障礙德國中心的一位神經成像學教授和神經學家。比如神經微絲輕鏈就是一種維持神經元軸突的結構蛋白，其可以將信號傳遞給其他神經元。 traumatic injury：創傷性損失 Vertigo and Balance Disorders：眩暈和平衡障礙 Neurofilament light chain：神經微絲輕鏈 In a healthy person, “you shouldn’t be detecting much of those structural proteins in the blood,” Kawata said. But if someone has a neurodegenerative condition, the proteins dislodge from the neurons and can get into the bloodstream. 對于一個健康的人，“你的血液中應該不會檢測到大部分這類結構蛋白，”Kawata表示。但是，如果一個人存在神經退變方面的疾病，神經元中的蛋白會移動并進入血液中。 Interpreting the results 結果解釋 The researchers measured five proteins 20 days before launch and calculated the average level for each protein across the five cosmonauts. They then compared this to the average level one day, one week, and 20 to 25 days after the cosmonauts returned to Earth. 研究人員在發射任務開始前20天測量了5種蛋白質并計算了5位航天員身體中每種蛋白質的平均含量。然后，研究人員將這一結果與宇航員返回地球后第1天、第1周和第20-25天的平均蛋白質含量進行對比。 Two of the proteins had elevated levels both one day and one week after the missions. These levels dropped over the next two weeks, but remained above the cosmonauts’ baseline level from before the missions. A third protein wasn’t significantly elevated in the first week after returning and had dropped below the baseline after three weeks, so it wasn’t indicative of potential brain damage. For the final two proteins, the researchers typically look at the ratio of one to the other. The ratio dropped after the cosmonauts returned, a trend that is sometimes seen in people with a neurodegenerative condition. 有兩種蛋白質的含量在任務結束后第1天和第1周有所增加并在接下來的2周有所下降。但是，含量仍然高于宇航員執行任務前的基準線。第三種蛋白在返回地球后的第1周并未明顯升高。經過三周后，第三種蛋白下降至基準線以下，因此其并不能表明宇航員存在潛在的腦損傷。對于兩種蛋白，研究人員觀察了它們之間的比率。它們的比率在宇航員返回地球后有所下降，這一趨勢偶爾會出現在有神經退變疾病的人群中。 zu Eulenburg said that the fact that some levels remained elevated for the entire three weeks was “very surprising,” and the results “verified brain injury as a consequence to long-duration exposure to microgravity.” Zu Eulenburg表示，在整整三周內，某些蛋白質的水平仍然保持升高狀態是“非常出乎意料的”，結果證明“長期暴露于微重力下會造成大腦損傷”。 “This is obviously a pilot study, but the data quality and the analytics are so robust that I have no doubt in the overall effect,” he said. 他說：“這顯然屬于探索性研究，但是數據的質量和分析學都十分具有說服力，所以我對總的結果持肯定意見。” The seriousness of these effects remains uncertain. Roberts said the paper contains “initial data suggesting that there is some type of injury to the brain,” but cautioned that more work needs to be done to show the effect on astronauts’ health. Kawata said the paper is not evidence that if you go to space, you’re going to get Alzheimer’s disease, for example. 這些影響的嚴重性仍屬于未知狀態。Roberts表示，論文含有“表明存在某類大腦損傷的初步數據”，但Roberts也審慎提出，要想具體了解其對宇航員健康的影響，則還需要完成更多的工作。Kawata表示，該論文并非證明，如果你前往太空，你就會患上帕金森。 Both Roberts and Kawata would like future studies to measure the biomarkers for longer than three weeks after astronauts return, as well as while they are on the space station, which would help determine if the elevated levels are due to time spent in microgravity, rather than the change in gravity upon return, or the intense force experienced during landing. Roberts和Kawata都贊成在宇航員返回地球后測定生物標記物的研究要超過三周并且還要在他們在太空站期間進行測定，這也許有助于測定蛋白質水平升高是由于在微重力下所持續的時間而不是在返回時重力發生變化或著陸時的巨大沖擊力所導致的。 Roberts said understanding the cause of the elevated biomarkers would help space agencies figure out which sorts of measures would best counteract the effects. zu Eulenburg thinks time spent in microgravity is the most likely cause, since imaging studies have shown that changes in the brain don’t occur for people on shorter trips, so the elevated levels might start while astronauts are still in space. Roberts表示，了解生物標記物升高的原因也許有助于航天機構制定最佳的應對措施。zuEulenburg認為，在微重力狀態下所持續的時間是最可能造成腦損傷的原因，因為腦成像研究顯示，太空航行時間較短的宇航員的大腦并未發生變化，因此蛋白質含量的升高也許就是在宇航員還停留在太空時開始的。 Kawata said it shouldn’t be a big problem if biomarkers are only elevated for a couple of weeks in total. But zu Eulenburg said via email that three weeks of elevated levels are a sign of a “substantial” reparatory process. And other studies have shown that changes in the brain and cognitive effects last for at least several months after spending months in space, suggesting that elevated biomarkers could last longer than a couple of weeks. Kawata表示，如果生物標記物僅僅升高了總共幾周，那么并沒有什么大問題。但zu Eulenburg通過郵件表示，生物標記物水平在三周內升高就是“重大”修復的跡象。另一項研究也顯示，在太空中花費數月后，大腦和認知的變化也會持續至少幾個月，這表明標記物升高的持續時間也會超過數周。 “I would feel very cautious about doing a one-year mission aboard the [space station] without sufficient countermeasures in place," said zu Eulenburg. “如果沒有充足的應對舉措，我會對在空間站工作1年持審慎的態度，”zu Eulenburg表示。 Roberts said she feels confident that science will be able to find ways to protect astronauts from adverse effects. “Ultimately our goal is to become a multiplanetary species… but we have to be smart about it along the way.” Roberts表示，她相信科學將可以找到保護宇航員免于副作用的方法。 “最終，我們的目標是成為多行星物種……但是在這一過程中，我們必須理智行事。” 原文來源：HOW STUFF WORKS 編輯&翻譯：Sarah，譯銳翻譯
