日本高清色视频在线视频在,国产香蕉97碰碰视频碰碰看,丰满少妇av无码区,精品无码专区在线,久久无码专区免费看,四虎欧美精品永久地址99,亚洲色无码一区二区三区

 
 
 

當(dāng)前位置: Language Tips> 雙語新聞

研究:空氣污染或可致自閉癥和精神分裂

Mice study links air pollution to autism, schizophrenia

中國日報網(wǎng) 2014-07-14 10:16

分享到

 

研究:空氣污染或可致自閉癥和精神分裂

查看原文

A new research describes how the brains of mice are damaged by exposure to air pollution in early life.

The brain damage includes the enlargement of a part of the brain that is seen in humans who have autismand schizophrenia.

The study is published in the journal Environmental Health Perspectives.

As in autism and schizophrenia, the changes occurred predominately in males. The mice also performed poorly in tests of short-term memory, learning ability, and impulsivity.

The new findings are consistent with several recent studies that have shown a link between air pollution and autism in children.

Most notably, a 2013 study in JAMA Psychiatryreported that children who lived in areas with high levels of traffic-related air pollution during their first year of life were three times as likely to develop autism.

“Our findings add to the growing body of evidence that air pollution may play a role in autism, as well as in other neurodevelopmental disorders,” said Deborah Cory-Slechta, Ph.D., professor of environmental medicine at the University of Rochester and lead author of the study.

In three sets of experiments, Cory-Slechta and her colleagues exposed mice to levels of air pollution typically found in mid-sized US cities during rush hour.

The exposures were conducted during the first two weeks after birth, a critical time in the brain’s development. The mice were exposed to polluted air for four hours each day for two four-day periods.

In one group of mice, the brains were examined 24 hours after the final pollution exposure. In all of those mice, inflammation was rampant throughout the brain, and the lateral ventricles —chambers on each side of the brain that contain cerebrospinal fluid —were enlarged two to three times their normal size.

“When we looked closely at the ventricles, we could see that the white matter that normally surrounds them hadn’t fully developed,” said Cory-Slechta.

“It appears that inflammation had damaged those brain cells and prevented that region of the brain from developing, and the ventricles simply expanded to fill the space.”

The problems were also observed in a second group of mice 40 days after exposure and in another group 270 days after exposure, indicating that the damage to the brain was permanent.

Brains of mice in all three groups also had elevated levels of glutamate, a neurotransmitter, which is also seen in humans with autism and schizophrenia.

Most air pollution is made up mainly of carbon particles that are produced when fuel is burned by power plants, factories, and cars. For decades, research on the health effects of air pollution has focused on the part of the body where its effects are most obvious —the lungs.

That research began to show that different-sized particles produce different effects. Larger particles, the ones regulated by the Environmental Protection Agency (EPA), are actually the least harmful because they are coughed up and expelled.

But many researchers believe that smaller particles known as ultrafine particles —which are not regulated by the EPA —are more dangerous, because they are small enough to travel deep into the lungs and be absorbed into the bloodstream, where they can produce toxic effects throughout the body.

That assumption led Cory-Slechta to design a set of experiments that would show whether ultrafine particles have a damaging effect on the brain, and if so, to reveal the mechanism by which they inflict harm. The study is the first scientific work to do both.

“I think these findings are going to raise new questions about whether the current regulatory standards for air quality are sufficient to protect our children,” said Cory-Slechta.

查看譯文

一項新研究表明,老鼠若在幼年期長期接觸污染大氣,腦部可能會受損。

這種受損包括大腦某一部分變腫大,就人類而言,變腫大的部分常出現(xiàn)在自閉者與精神分裂患者腦中。

相關(guān)研究結(jié)果已發(fā)布在《環(huán)境健康透視》雜志上。

就自閉癥和精神分裂而言,這種變化更多出現(xiàn)在雄性之中。此外,試驗中雄性小鼠的短期記憶、學(xué)習(xí)能力和沖動性行為均有下降。

除本實驗外,其他最近幾項研究也表明大氣污染可導(dǎo)致兒童自閉癥。

最顯著的是2013年《美國醫(yī)學(xué)協(xié)會雜志:精神病學(xué)分冊》上發(fā)表的一項研究,該研究顯示兒童若在一歲多時生活在交通尾氣污染嚴(yán)重地區(qū),患上自閉癥的概率是同齡兒童的三倍。

“隨著調(diào)查的深入,我們搜集到的證據(jù)也越來越多,這些數(shù)據(jù)一致表明大氣污染和自閉癥之間存在必然聯(lián)系,污染甚至還可能引發(fā)神經(jīng)系統(tǒng)發(fā)育障礙,”羅切斯特大學(xué)環(huán)境醫(yī)學(xué)教授德博拉?科里?斯徹塔解釋道。

在三組試驗中,斯徹塔與同事采集了美國二線城市交通高峰期的空氣樣本,并將老鼠置于其中。

科里?斯徹塔用出生僅兩周的老鼠進行試驗,此時正值其腦部發(fā)育的關(guān)鍵時期。試驗期間,小鼠每天要呼吸污染的空氣長達四個小時,為期兩到四天,試驗分為兩期進行。

試驗結(jié)束后,科里為第一組小鼠進行了長達二十四小時的腦部檢查。所有小鼠的大腦和側(cè)腦室均已嚴(yán)重發(fā)炎——左右腦的腦腔里都是腦脊髓液——小鼠的大腦增大兩至三倍。

“我們仔細(xì)檢查了小鼠的腦室,發(fā)現(xiàn)大腦的白質(zhì)未完全發(fā)育”,科里?斯徹塔說道。

“我們觀察發(fā)現(xiàn)炎癥損害了小鼠的腦細(xì)胞,限制了大腦的發(fā)育,腦室不斷擴張,占滿了整個大腦?!?/p>

科里?斯徹塔還在試驗后40天和270天分別測試了第二和第三組小鼠,發(fā)現(xiàn)大氣污染對腦部造成的傷害是永久性的。

三組小鼠的腦內(nèi)的谷氨酸水平也明顯升高,谷氨酸是一種神經(jīng)遞質(zhì),如果人類腦部的谷氨酸水平過高,則會患上自閉癥和精神分裂。

空氣污染產(chǎn)生的主要原因是發(fā)電廠,工廠和汽車燃燒燃料后排放出的碳粒子。幾十年來,在研究大氣污染對健康的影響時,人們往往只關(guān)注病癥最明顯的部位——肺。

隨著研究的深入,研究人員漸漸發(fā)現(xiàn)不同大小的碳顆粒對大腦的損害不同。大型碳顆粒受美國環(huán)保局監(jiān)管,其實會被人體咳出或排出,危害最小。

但許多研究者認(rèn)為那些小型碳顆粒,又叫做超微顆?!皇苊绹h(huán)境保護局監(jiān)管——其實危害更大,因為小型碳顆粒體積較小,可能會被吸入肺部或是融入血液,從而毒害人體。

為驗證上述猜想,科里?斯徹塔設(shè)計了一系列實驗,探究超微粒子是否會危害大腦,如果答案是肯定的,科里還將深入研究超微碳粒子是如何危害人體的??评锝Y(jié)合了這兩方面來研究,開創(chuàng)了先河。

“現(xiàn)在的空氣質(zhì)量的監(jiān)管標(biāo)準(zhǔn)能否保護我們的孩子呢?我覺得我的研究成果可能會起到警示的作用”,科里?斯徹塔說道。

(譯者 rosemary02 編輯 丹妮)

掃一掃,關(guān)注微博微信

研究:空氣污染或可致自閉癥和精神分裂 研究:空氣污染或可致自閉癥和精神分裂

 

分享到

中國日報網(wǎng)英語點津版權(quán)說明:凡注明來源為“中國日報網(wǎng)英語點津:XXX(署名)”的原創(chuàng)作品,除與中國日報網(wǎng)簽署英語點津內(nèi)容授權(quán)協(xié)議的網(wǎng)站外,其他任何網(wǎng)站或單位未經(jīng)允許不得非法盜鏈、轉(zhuǎn)載和使用,違者必究。如需使用,請與010-84883561聯(lián)系;凡本網(wǎng)注明“來源:XXX(非英語點津)”的作品,均轉(zhuǎn)載自其它媒體,目的在于傳播更多信息,其他媒體如需轉(zhuǎn)載,請與稿件來源方聯(lián)系,如產(chǎn)生任何問題與本網(wǎng)無關(guān);本網(wǎng)所發(fā)布的歌曲、電影片段,版權(quán)歸原作者所有,僅供學(xué)習(xí)與研究,如果侵權(quán),請?zhí)峁┌鏅?quán)證明,以便盡快刪除。

中國日報網(wǎng)雙語新聞

掃描左側(cè)二維碼

添加Chinadaily_Mobile
你想看的我們這兒都有!

中國日報雙語手機報

點擊左側(cè)圖標(biāo)查看訂閱方式

中國首份雙語手機報
學(xué)英語看資訊一個都不能少!

關(guān)注和訂閱

本文相關(guān)閱讀
人氣排行
熱搜詞
 
 
精華欄目
 

閱讀

詞匯

視聽

翻譯

口語

合作

 

關(guān)于我們 | 聯(lián)系方式 | 招聘信息

Copyright by chinadaily.com.cn. All rights reserved. None of this material may be used for any commercial or public use. Reproduction in whole or in part without permission is prohibited. 版權(quán)聲明:本網(wǎng)站所刊登的中國日報網(wǎng)英語點津內(nèi)容,版權(quán)屬中國日報網(wǎng)所有,未經(jīng)協(xié)議授權(quán),禁止下載使用。 歡迎愿意與本網(wǎng)站合作的單位或個人與我們聯(lián)系。

電話:8610-84883645

傳真:8610-84883500

Email: languagetips@chinadaily.com.cn

<strong id="xdwva"><div id="xdwva"></div></strong>
<label id="xdwva"></label>

<thead id="xdwva"></thead>
    <label id="xdwva"></label>

  1. 日本高清色视频在线视频在,国产香蕉97碰碰视频碰碰看,丰满少妇av无码区,精品无码专区在线,久久无码专区免费看,四虎欧美精品永久地址99,亚洲色无码一区二区三区