Reading for Writing & Speaking 1
写作和口语阅读 1
Read the following essay from Nature and give a 3-minute speech which includes the context, purpose, materials and method, result and discussion of the research.
阅读以下来自 Nature 的文章并发表 3 分钟的演讲,其中包括研究的背景、目的、材料和方法、结果和讨论。
Links between gut microbes* and depression strengthened Feb. 4th, 2019 |503 words 1 The once-wild idea that1 intestinal bacteria influence mental health has transformed into a major research pursuit2 2 Just ten years ago, the idea that microorganisms* in the human gut could influence the brain was often dismissed as wild3. Not any more. 3 Links between the central nervous system4 and the trillions of bacteria in the gut — the microbiota — are now a major focus of research5, public interest and press coverage. But how does this ‘gut–brain axis’ work? The mechanisms by which microorganisms shape aspects of brain functioning such as memory and social behaviour, and how they might contribute to conditions such as depression and neurodegenerative* disease, are tenuous and often controversial6 4 Much of what we know so far is based on studies showing correlations between specific gut bacteria, their metabolites and neurological symptoms. But these correlations do not prove cause and effect7. Many studies use animal models, which don’t accurately mirror human traits or behaviours8. Human studies have been limited: they’re usually based on relatively small numbers of people, and might not control for a wealth of confounding factors9 — such as unusual diets, antibiotics or antidepressants — that can affect the microbiota. 5 A study published this week in Nature Microbiology10 tackles some of these issues (M. Valles-Colomer et al. Nature Microbiol. https://doi.org/10.1038/s41564-018-0337-x; 2019). The authors used DNA sequencing to analyse microbiota in the faeces* of more than 1,000 people enrolled in Belgium’s Flemish Gut Flora Project. The team then correlated different microbial taxa* with the participants’ quality of life and incidence of depression, using self-reported and physician-supplied diagnoses11. The researchers validated the findings12 in an independent cohort of 1,063 individuals in the Netherlands’ LifeLines DEEP project. Finally, they mined the data to13 generate a catalogue describing the microbiota’s capacity to produce or degrade molecules that can interact with the human nervous system. 6 The researchers found that two groups of bacteria, Coprococcus and Dialister, were reduced in people with depression. And they saw a positive correlation between14 quality of life and the potential ability of the gut microbiome* to synthesize a breakdown product of the neurotransmitter dopamine, called 3,4-dihydroxyphenylacetic acid. The results are some of the strongest yet to15 show that a person’s microbiota can influence their mental health. 7 These are still correlations, not causes.16 Researchers know that the gut microbiota can produce or stimulate the production of neurotransmitters and neuroactive compounds, such as serotonin, GABA and dopamine, and that these compounds can modulate* bacterial growth. The challenge now is to find out whether, and how, these microbe-derived molecules can interact with the human central nervous system, and whether that alters a person’s behaviour or risk of disease17. At least now, answering these questions is a wise pursuit, not a wild one.18 Nature 566, 7 (2019) doi: 10.1038/d41586-019-00483-5 | *microbe['maɪkrəʊb] n. 微生物 *gut microbes肠道菌群 1. 曾经很不靠谱的想法 2. 一个很重要的研究课题 *microorganism[maɪkrəʊ'ɔːg(ə)nɪz(ə)m] n. [微] 微生物 3. 被认为是无稽之谈 4. 中枢神经系统 5. 重点研究领域 6. The mechanism by which ... are tenuous and often controversial.对机制不是很确定,也很有争议 *neurodegenerative [,nju:rəudi'dʒenərətiv] adj. 神经变性的... 7. 但这些只表明了相关而非因果 8. 不能很好地反应人类的特点和行为 9. 大量的干扰因素 10. 这周发表在《自然---微生物学》上 的一项研究 *faeces ['fiːsiːz] n. [生理] 粪便 *microbial taxa微生物类群 11. 利用自述和医生的诊断 12. 研究者们验证了他们的发现 13. 挖掘分析了数据 14. 他们发现......和......正相关 microbiome微生物群系 *a breakdown product 分解产物 15. 其结果是目前为止最有力的 16. 这也只表明相关性而非因果关系。 *modulate['mɒdjʊleɪt] vt. 调节 17. 改变一个人的行为和患病可能性 18. 至少现在这些研究不再被认为是不靠谱的想法了 |