科学家找到可能触发 阿尔兹海默症记忆衰退“机关”******
科技日报讯 (记者刘园园)记者1月15日从西湖大学获悉,该校施一公团队历经8年探索,在阿尔兹海默症领域取得重要发现——他们找到了可能触发阿尔兹海默症记忆衰退的“机关”。这一发现对理解阿尔兹海默症的发病机制,以及开展针对性的药物设计,具有重要意义。相关研究结果日前在线发表于《细胞研究》。
“阿尔兹海默症,俗称老年痴呆症,记忆衰退是这种疾病最显著的临床表现之一。”本文共同第一作者、西湖大学生命科学学院博士后周家耀说,阿尔兹海默症的原理和机制迄今尚未明确。
随着基因测序技术的发展,科学家发现,APOE4是阿尔兹海默症最大的风险基因。APOE蛋白是人体载脂蛋白之一,在人群中有APOE2、APOE3和APOE4这3种亚型。研究发现,APOE2的携带者,不易患阿尔兹海默症;而APOE4的携带者,患病风险成倍增加。因此,找到APOE4的受体可能是破解阿尔兹海默症的关键。
此前研究发现,小胶质细胞对神经突触的剪切功能会在阿尔兹海默症患者中被异常激活,从而导致患者失忆。而小胶质细胞能否执行功能,可能与LilrB蛋白有关。
APOE蛋白与LilrB蛋白之间是否存在某种联系?这或许是破解阿尔兹海默症发病机制的重要线索。
“在大量研究基础上,我们建立起新猜测:LilrB家族蛋白和APOE蛋白有相互作用,并且只和APOE4结合而不与APOE2结合。”周家耀解释说,这一猜想如成立,或有可能解释阿尔兹海默症的生物化学原理:APOE4与LilrB蛋白结合,激活小胶质细胞,导致神经突触被剪切,进而导致记忆衰退并引发阿尔兹海默症。
为验证新猜想,研究团队开展了一系列实验,系统研究了LilrB人源家族的5个同源蛋白和3个APOE亚型之间的相互作用。结果正如预期:APOE4与LilrB3可以结合,APOE3结合较弱,而APOE2几乎完全不结合。他们还进一步证实了小胶质细胞因为这种结合而“苏醒”的事实,即APOE4与LilrB3结合后,会激活小胶质细胞。
“这项研究找到了阿尔兹海默症患者记忆衰退的机制,为人类对付阿尔兹海默症带来一线曙光。”周家耀介绍,接下来,研究团队将在该成果基础之上,继续开展阿尔兹海默症相关研究,并着眼于阿尔兹海默症的药物研发。
中新网评:处理核污水绝不是日本自家私事******
中新网北京1月19日电(蒋鲤)日本政府近日称,将于2023年春夏期间开始向海洋排放经过处理的福岛第一核电站核污水。日本罔顾国内民众及周边国家的屡屡反对,企图将核污水“一倒了之”,把一件关乎全球海洋生态环境和公众健康的事当成了自家私事。
资料图:日本福岛第一核电站。2011年,福岛核电站事故发生后,大量放射性物质泄漏到大气层和太平洋,对周围环境造成了难以逆转的伤害,数十万人被迫撤离该地区。时至今日,作为日本邻国之一的韩国仍未解除福岛海鲜禁令。
日本以核污水存储能力即将达到上限为由,在2021年4月13日,正式决定将福岛第一核电站核污水排入太平洋。过去一年多,日本政府和东京电力公司一直在持续推进核污水排海计划。
日本政府辩称,这些核污水经多核素处理系统(ALPS)处理后很安全,甚至“可以喝”,这样的表态无疑在愚弄大众。
事实上,经过处理的核污水仍含有多种放射性物质,核污水一旦排放入海就无法回收,长期来看,将会给海洋生态带来难以估量的潜在威胁,最终危害人类健康。
因此,核污水排海计划推出后,遭到日本民众强烈反对。日本《朝日新闻》2022年3月公布的问卷调查显示,福岛县、宫城县和岩手县受访的42个市町村长中,约六成反对东京电力公司福岛第一核电站核污水排放入海。日本全国渔业协会联合会也多次申明立场,反对该计划。
日本政府认为,核污水排海是最便宜、最省事的解决方案,但此举却将周边国家乃至全世界置于核污染风险中。太平洋非日本一家之海,核污水会随着洋流流动,其影响势必会跨越国界,危害周边国家乃至整个国际社会的公共福祉和利益。
《韩国经济新闻》发文称,相关研究认为,福岛核污水如果排放入海,约7个月后将到达济州等韩国海域,该国水产业和旅游业将遭受相当大的损失。
德国南极海洋机构也曾发出警告,若日本将所有核污水排入海中,不到半年,整个太平洋都将面临高度辐射威胁,包括远在大洋另一端的美国。太平洋地区人民更是对日本该计划持反对意见。
日本作为《联合国海洋法公约》缔约国,有义务保护海洋环境。然而,在核污水排海方案的正当性、核污水数据的可靠性、净化装置的有效性、环境影响的不确定性等问题上,日本未能作出科学、可信的说明。
国际原子能机构技术工作组虽已三次赴日实地考察评估,但尚未就日排海方案的安全性给出结论,并且对日本提出诸多澄清要求和整改意见。在此情况下,日本仍执意推进核污水排海工程建设,这是极不负责任的行为。
太平洋不是日本的下水道,日本必须正视各方合理关切,在与周边国家等相关利益方和国际原子能机构充分协商后,制定合理的核污水处理方案。日本也要着眼长远,若只顾眼前,执意将核污水排放入海,不仅其自身,周边国家乃至全世界都将为之买单,其后果必将会危害数代人。
Fukushima water disposal by no means Japan’s own business
By John Lee
(ECNS) -- Japan has announced it will release treated wastewater from the wrecked Fukushima Daiichi Nuclear Power Plant into the Pacific Ocean this year.
Although Fukushima wastewater disposal affects global marine ecological environment protection and public health, Japan has turned a deaf ear to domestic and international opposition to dumping the contaminated water into the sea, treating the "global" matter as its own business.
The Fukushima accident in 2011 had sent large quantities of radiation into the atmosphere and the Pacific Ocean, causing irreversible damage to the surrounding environment, and hundreds of thousands of people were forced to evacuate the area. South Korea still maintains its import ban on Japanese seafood from areas affected by the Fukushima nuclear disaster.
On April 13, 2021, Japan announced it had decided to discharge contaminated radioactive wastewater in Fukushima Prefecture into the sea due to dwindling storage space, with the Japanese government and plant operator Tokyo Electric Power Company Holdings Inc. promoting the release plan over the past year.
The Japanese government argues that the water treated by an advanced liquid processing system, or ALPS, is safe and drinkable, which is undoubtedly fooling the public.
In fact, the treated wastewater still includes a variety of radioactive substances and can’t be recycled once discharged into the sea, which will pose a great threat to marine ecology and ultimately endanger human health in the long run.
Therefore, the discharge plan has been strongly opposed in Japan. According to a questionnaire conducted by The Asahi Shimbun, nearly 60 percent of mayors of 42 municipalities in Iwate, Miyagi and Fukushima prefectures oppose the discharge plan. The National Fisheries Cooperative Federation of Japan has also repeatedly stated its opposition in public.
The Japanese government believes that dumping Fukushima wastewater into the sea is the cheapest and most convenient solution, but neighboring countries and even the whole world will be at risk of nuclear pollution.
The Pacific Ocean doesn’t belong to Japan and the wastewater flow along oceanic currents will surely break boundaries and endanger public welfare and the interests of neighboring countries and even the international community.
The Korea Economic Daily reported that related research concluded that if contaminated water from Fukushima is released into the ocean, it would only take seven months for the contaminated water to reach the shores of Jeju Island, with the country's aquaculture and tourism suffering considerable losses.
According to the calculation of a German marine scientific research institute, radioactive materials will spread to most of the Pacific Ocean within half a year from the date of discharge, and the U.S. and Canada will be affected by nuclear pollution. People in the Pacific region also oppose the discharge plan.
As a participant of the United Nations Convention on the Law of the Sea, Japan has the obligation of protecting the marine environment.
However, it hasn’t offered a full and convincing explanation on issues like the legitimacy of the discharge plan, the reliability of data on the nuclear-contaminated water, the efficacy of the treatment system or the uncertainty of environmental impact.
Though the IAEA has yet to complete a comprehensive review after three investigations in Japan, the Japanese side has been pushing through the approval process for its discharge plan and even started building facilities for the discharge. It is rather irresponsible for Japan to act against public opinion at home and concerns abroad.
The Pacific Ocean is not a private Japanese sewer. The country must seriously heed the voices of the international community and make a reasonable plan for the Fukushima wastewater disposal after full consultation with stakeholders and international agencies.
If it only seeks instant interest and insists on discharging the contaminated water into the sea, not only itself, but also its neighboring countries and the entire world will pay for the decision and several generations will be forced to bear the consequence.
(文图:赵筱尘 巫邓炎) [责编:天天中] 阅读剩余全文() |