The presence of viruses in the brain has been linked to Alzheimer's disease in research that challenges conventional theories about the onset of dementia.
The results, based on tests of brain tissue from nearly 1, 000 people, found that two strains of herpes virus were far more abundant in the brains of those with early-stage Alzheimer's than in healthy controls. However, scientists are divided on whether viruses are likely to be an active trigger, or whether the brains of people already on the path towards Alzheimer's are simply more vulnerable to infection.
The scientists could not prove whether viruses actively contribute to the onset of disease, but they discovered a plausible mechanism for how this could happen. Some of the herpes genes were found to be boosting the activity of several known Alzheimer's genes.
However, others were more sceptical. Prof John Hardy, a geneticist at UCL, said: “There are some families with mutations in specific genes who always get this disease. It’s difficult to square that with a viral aetiology. I'd urge an extremely cautious interpretation of these results.”
There are currently 850, 000 people living with dementia in Britain, and the number is projected to rise to a million by 2025 and 2 million by 2050. But despite hundreds of drug trials during the past decade, an effective treatment has not yet emerged.
————— 文章来源 / 卫报
Alzheimer's /ˈæltshaɪmərz／
n. 阿尔茨海默症；老年痴呆症
herpes /ˈhɜːrpiːz/
n. 疱疹
control/kənˈtroʊl/
n. 对照组
onset /ˈɔːnset/
n. （疾病的）发作；开始
dementia /dɪˈmenʃə/
n. （尤指老年性）痴呆症
e.g.
The most common form of dementia is Alzheimer's disease.
strain /streɪn/
n.（动植物的）品系，株系
e.g.
a new strain of the virus
vulnerable /ˈvʌlnərəbl/
adj. 脆弱的；易受伤害的
e.g.
Children are most vulnerable to abuse.
infection/ɪnˈfekʃn/
n. （细菌或病毒）感染 (infect v.)
e.g.
a throat infection
plausible /ˈplɔːzəbl/
adj. 貌似真实可信的
e.g.
a plausible excuse
mechanism /ˈmekənɪzəm/
n. 机制
sceptical/ˈskeptɪkl/
adj. 持怀疑态度的
e.g.
I am highly sceptical about his chances of winning.
geneticist /dʒəˈnetɪsɪst/
n. 遗传学家
mutation /mjuːˈteɪʃn/
n. （基因）突变
e.g.
mutant
square /skwer/
v. 与...一致
e.g.
square his goal with his belief
aetiology/ˌiːtiˈɑːlədʒi/
n. 病因学
project/ˈprɑːdʒekt/
v. 预计
live with sth.
在...下生活；承受
e.g.
live with my husband's anxiety
