首页
登录
职称英语
Scientists say they have high hopes for a drug that could one day provide a
Scientists say they have high hopes for a drug that could one day provide a
游客
2023-08-29
10
管理
问题
Scientists say they have high hopes for a drug that could one day provide a new form of treatment for HIV-AIDS. A compound, which interferes with an elusive protein used by the HIV virus to infect human cells, has worked extremely well in monkeys. If the drug proves effective in human trials, scientists say, it could bolster (加强) the effectiveness of two existing AIDS drugs, particularly in fighting drug-resistant strains of the virus.
Researchers at the pharmaceutical (制药的) company Merck are very excited about an experimental drug, which has worked as well in monkeys infected with a primate version of the virus as any of the existing anti-AIDS drugs.
It works by blocking one of three proteins, or enzymes, the HIV virus uses to gain entrance into and infect human immune system cells.
Inhibitor drugs have been developed to block two of the proteins, to slow progression of the disease after infection. They have become standard therapy as a "cocktail" for people infected with HIV.
Those enzymes are reverse transcriptase (转录酶) and protease (蛋白酶). The first converts the virus’ genetic material into that of its host cells. The second chops up the resulting larger proteins into smaller pieces, producing smaller viral particles that infect new cells.
The third prong of cellular attack is a protein called integrase (整合酶), which experts say has been harder to block. Once HIV fools host cells by changing its genetic information so it can enter them, integrase acts like a cut and paste operation in a word processor, deleting an immune cell’s genetic material and replacing it with its own.
An integrase inhibitor would give doctors a third line of attack against HIV infection, according to virologist Daria Hazuda of the division of Virus and Cell Biology at Merck.
"This would offer a third class of anti-retroviral medications that can be combined with reverse transcriptase inhibitors and protease inhibitors. And since it is a new mechanism of action, these compounds are active against multi-drug resistant variants. So variants that are resistant to all current therapies have been selected in HIV-patients," she said.
Current anti-AIDS drugs eventually become resistant to therapy, or stop working, because the virus changes its shape.
While researchers are encouraged by the success with the compound’s effectiveness in monkey trials, developing a drug that is equally effective in humans-can be difficult.
Steven Young is executive director of the Department of Medicinal Chemistry at Merck. He says, if scientists find a compound that is equally effective in people, the company would ask U. S. regulators to speed approval of the drug.
"Yeah, I really think that’s what we’re hoping for," he said. "I mean, we need to get data that show it has robust anti-viral effects in people. And if we’re able to get that data, I think we would petition for fast track status."
Dr. Young says an integrase inhibitor has the potential to prevent drug resistance.
"To ensure our best chance of preventing resistance, we would give this as part of a cocktail therapy," he added. "And I think it’s really our plan that we would test this with reverse transcriptase inhibitors and protease inhibitors, as well." [br] Why would anti-AIDS drugs stop working? ______.
选项
答案
Because the virus changes its shape
解析
根据题干中的“anti—AIDS drugs”和“stop working”可定位到第9段。答案明显为Becausethe virus changes its shape。
转载请注明原文地址:https://tihaiku.com/zcyy/2968106.html
相关试题推荐
[originaltext]Foryearsscientistshavebeenworriedabouttheeffectsof
[originaltext]Foryearsscientistshavebeenworriedabouttheeffectsof
Agrowingnumberofscientistsinsistthatanswerstotheworld’sproblemsw
Agrowingnumberofscientistsinsistthatanswerstotheworld’sproblemsw
Agrowingnumberofscientistsinsistthatanswerstotheworld’sproblemsw
Agrowingnumberofscientistsinsistthatanswerstotheworld’sproblemsw
Consumershadbetterchooseaproviderofacreditcardwith______.[br]Whatd
Consumershadbetterchooseaproviderofacreditcardwith______.[br]Ifyou
[originaltext]Americanscientistsaredevelopingmapsthatcanidentifyare
[originaltext]Americanscientistsaredevelopingmapsthatcanidentifyare
随机试题
Howmuchisthebudgetplanfor2005?[br][originaltext](21[D])TheHouse
[originaltext]W:Excuseme,IwanttomakethreereservationsonFlight732for
“该出手时就出手啊,风风火火闯九州啊”,这首歌曲的曲调参考了()地区的民歌。
成年男性红细胞参考值是()A.(3.5~4.5)×10/LB.(5.0~6.0
某教育机构招聘讲师,有5位评委打分,平均分需要达到85分才能正式通过。小王应聘时
以下关于短期出口信用保险的内容正确的是( )。 A.短期出口信用保险的保单
草皮土质护坡的坡比值应小于或等于()。A.0.3 B.0.5 C.0.6
下列不属于被动防火措施的是()。A.防火分隔设施 B.防火分区 C.防烟排
根据《城市轨道交通岩土工程勘察规范》(GB50307—2012)下列关于岩石风
某水利枢纽由混凝土重力坝、引水隧洞和电站厂房等建筑物组成,最大坝高150m,
最新回复
(
0
)