Why hydroxychloroquine and chloroquine don't block SARS-CoV-2 infection of human lung cells
Why hydroxychloroquine and chloroquine don't block SARS-CoV-2 infection of human lung cells
The Research Brief is a short take about interesting academic work. The big ideaA paper came out in Nature on July 22 that further underscores earlier studies that show that neither the malaria drug hydroxychloroquine nor chloroquine prevents SARS-CoV-2 – the virus that causes COVID-19 – from replicating in lung cells. Most Americans probably remember that hydroxychloroquine became the focus of numerous clinical trials following the president's statement that it could be a "game changer." At the time, he appeared to base this statement on anecdotal stories, as well as a few early and very limited studies that hydroxychloroquine seemed to help patients with COVID-19 recover.Many in the antiviral field, including myself, questioned the validity of both, and in fact, one of the papers was later disparaged by the scientific society and the editor of the journal that published it.Since then, HQC has had a bumpy ride. It was initially approved by the FDA for emergency use. The FDA then quickly reversed its decision when numerous reports of deaths caused by heart arrhythmias emerged. That news brought many clinical trials to a halt. Regardless, some scientists continued to study it in hopes of finding a cure for this deadly virus. How the work was doneThe new study was carried out by scientists in Germany who tested HCQ on a collection of different cell types to figure out why this drug doesn't prevent the virus from infecting humans. Their findings clearly show that that HQC can block the coronavirus from infecting kidney cells from the African green monkey. But it does not inhibit the virus in human lung cells – the primary site of infection for the SARS-CoV-2 virus. In order for the virus to enter a cell, it can do so by two mechanisms - one, when the SARS-CoV-2 spike protein attaches to the ACE2 receptor and inserts its genetic material into the cell. In the second mechanism, the virus is absorbed into some special compartments in cells called endosomes. Depending on the cell type, some, like kidney cells, need an enzyme called cathepsin L for the virus to successfully infect them. In lung cells, however, an enzyme called TMPRSS2 (on the cell surface) is necessary. Cathepsin L requires an acidic environment to function and allow the virus to infect the cell, while TMPRSS2 does not. [Deep knowledge, daily. Sign up for The Conversation's newsletter.]In the green monkey kidney cells, both hydroxychloroquine and chloroquine decrease the acidity, which then disables the cathepsin L enzyme, blocking the virus from infecting the monkey cells. In human lung cells, which have very low levels of cathepsin L enzyme, the virus uses the enzyme TMPRSS2 to enter the cell. But because that enzyme is not controlled by acidity, neither HCQ and CQ can block the SARS-CoV-2 from infecting the lungs or stop the virus from replicating. Why it mattersThis matters for several reasons. One, much time and money has been spent studying a drug that many scientists said from the very beginning was not going to be effective in killing the virus.The second reason is that the studies that have reported antiviral activity for hydroxychloroquine were not in epithelial lung cells. Thus, their results are not relevant to properly studying SARS-CoV-2 infections in humans. What's next?As scientists proceed with investigating new drugs as well as trying to repurpose old ones, like hydroxychloroquine, it is critical that researchers take the time to think about their study design. In short, those of us involved in antiviral drug development should all take a lesson from this study. It is important not only to focus our efforts on pursuing drugs that will directly shut down viral replication, but also to study the virus in the primary site of infection.This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts.Read more: * Hydroxychloroquine for COVID-19: A new review of several studies shows flaws in research and no benefit * A small trial finds that hydroxychloroquine is not effective for treating coronavirusKatherine Seley-Radtke receives funding from the National Institutes of Health and the National Institutes of Allergies and Infectious Diseases.
Former Trump official told US attorneys there should be no age limit on child separations, report says
Rod Rosenstein, the former deputy attorney general, told US attorneys that there was no categorical exception for children under five under the then-active Trump Administration child separation policy for immigrants caught crossing the border illegally.The discussion occurred in 2018 on a conference call meant to clarify the "zero-tolerance" implementation of the Trump Administration's policy.
Алюминий в чушках
Первичный алюминий А0 (технической чистоты) поставляется по ГОСТ 11069-2001. Содержание алюминия не менее 99,70%. Содержание других веществ: кремний 0,15 железо 0,16 медь 0,01 марганец 0,03 магний 0,02 цинк 0,04 галлий 0,03 титан 0,01 прочие примеси не более 0,03 каждой в отдельности. Слиток отмечается двумя черными вертикальными полосами.
Алюминий А0 поставляется чушками. Вес одной чушки: 14-16 килограмм. Чушки упаковываются в пачки, вес каждой пачки от 800 до 1000 кг. Купить алюминий А0 в чушках вы можете в компании "Алюминий" в чушках А7 от производителя купить алюминий. Минимальная партия поставки алюминия А0 от 20 тонн. По договоренности возможна поставка меньшего тоннажа, но не менее одной пачки слитков. Т. е. пачки не распаковываются.
Fifteen people injured in shootout at Chicago funeral
"We thought it was a war out here," a neighbor said after a car opened fire during a funeral and mourners fired back.
California Cops Scramble to Find Special Needs Toddler After Parents Stop Cooperating
California authorities on Thursday continued their desperate search for a special needs toddler who has been missing for over a week—a search made more difficult now that his parents have "stopped cooperating" with investigators. Thaddeus Sran, 2, was reported missing on July 15 after his parents said he vanished from their home in Madera, about 30 minutes outside Fresno, the City of Madera Police Department said in a statement. His parents told police that they put the toddler to bed around 10 p.m. but when they woke up to check on their son at around 8:30 a.m. the next morning, he was gone.But while City of Madera Police Chief Dino Lawson called the incident "a parent's worst nightmare" last week, authorities are now alleging that the couple has not helped in the ongoing search for the 2-year-old. "Unfortunately, Thaddeus' parents stopped cooperating early on in the investigation. We believe their assistance, in this case, would be helpful," the police said in a statement to The Daily Beast. "We are hopeful that they will resume cooperating with Madera Police Department detectives and help us to locate Thaddeus."The police department, which did not provide the parents' names or say if the couple has been accused of any crime, has been extremely tip-lipped about their investigation. Stressing that they "will not stop looking for Thaddeus," the department declined to give any updates on the case. According to his missing person's poster, Thaddeus was last seen wearing a red shirt and Spiderman pants with a diaper underneath. Authorities said an Amber Alert was never issued for the 30-pound child because there was no information about a possible vehicle. Police added that the toddler's family has offered a $5,000 reward for any information to help find him. Lawson also revealed last week that the toddler had "severe health issues" after he was born prematurely. He said that Thaddeus, who is non-verbal, uses a feeding tube and is just learning how to walk. "Everything is on the table and we're not ruling anything out," Lawson said about the investigation, adding that authorities are looking into the possibility the toddler's disappearance was a possible abduction. Madera Police Lt. Josiah Arnold also revealed to NBC News that the toddler's parents had another daughter who died in 2015, but declined to provide further details. He added, however, that Thaddeus' sister's death was investigated and the case remains open. On Tuesday evening, dozens of residents who have been helping in the search for Thaddeus, including a group of mothers, hosted a vigil at Courthouse Park with candles, photos, and posters asking for "prayers." Many attendees wore red and blue, the colors of Thaddeus' Spiderman pants. "We just want to bring him home safe and alive," Sunndeep Sran, Thaddeus's father's second cousin, told YourCentralValley. She added that while her children go to school with the toddler's siblings, she has not spoken to her cousin since March. "The Sran family appreciates every effort everyone is making," Sran said. "We know as much as the media, what the police department is saying, so we are all in support of bringing Thaddeus home."Lawson said that the Madera County Sheriff's Office, U.S. Marshals, and the FBI were aiding in the case. He said authorities were "hopeful" the toddler's parents "will resume cooperating and come back in and speak with our detectives."Read more at The Daily Beast.Get our top stories in your inbox every day. Sign up now!Daily Beast Membership: Beast Inside goes deeper on the stories that matter to you. Learn more.
Уголок равнополочный является сегодня довольно популярным материалом. С ним взаимодействуют во многих отраслях. Это обусловлено отменными эксплуатационными данными изделий: он прочный и в то же время легкий. Поэтому их все чаще можно увидеть там, где невозможно применение его аналога из стали.
Помимо перечисленных характеристик, равнополочные уголки отличаются долговечностью, переносимостью воздействия как высоких, так и низких температур. Алюминиевый равнополочный уголок обладает высокой устойчивостью к коррозии, ультрафиолетовых лучей, химических жидкостей, кислот и влаги. При взаимодействии с воздухом на его поверхности возникает окисная пленка, которая играет роль барьера и увеличивает период его эксплуатации.
Также на уголки равнополочные может быть нанесено покрытие одним из методов:
распыление полимерной порошковой краски;
декорирование и ламинирование;
анодирование (путем создания на поверхности алюминия оксидного слоя).
Разные составы цветовых решений позволяют вписать их в производственный цикл для производства шкафов-купе, гардеробных комнат и прочей домашней мебели. Вышеприведенные нюансы помогут оценить их особенности, анодированные равнополочные уголки пользуются популярностью у многих потребителей - организаций и частных лиц.
Еще одно достоинство заключается в том, что они без каких либо проблем поддаются практически любой механической обработке. Его можно сверлить, шлифовать и придавать ему разлиную форму. Для их скрепления используются саморезы.
Как делаются уголки равнополочные
Производство их, как правило, осуществляется экструзией или гибкой. В зависимости от технологии выделяют вот два типа:
прессованные;
гнутые.
При этом они могут поступать в продажу в исходном состоянии или подвергнутые одному из нескольких способов термообработки. Экструдируют их на мощных гидравлических прессах через формообразующий элемент - фильеру, или так называемую матрицу. Гнут на гибочных станках. Стоить отметить, что им свойственно иметь более десятков тысяч размеров. Наиболее маленьким считается размер 10х10х1 мм, его противоположность, габарит 200 мм шириной и 200 мм высотой.
И так, подведем итоги: сплошной профиль, гораздо надежнее поливинилхлорида и дерева, так как не боится температурных скачков, алюминию не страшны жара и морозы, он устойчив к негативным атмосферным проявлениям. Они, профили, не воспламеняются и не поддерживают процесс горения, не продуцируют токсинов даже в случае нагревании, что дает возможность использовать их в жилых помещениях. Они не выделяет в атмосферу ядовитых веществ, абсолютно безвредны для человека. И монтировать их - одно удовольствие, скажем так, достаточно просто. Кроме того, они просты в обслуживании. И самое главное, они отличаются доступной ценой.
Где купить алюминиевый равнополочный уголок оптом и в розницу?
В магазинах расположенных по адресам: магазин Алюминий Бережанская 9 Киев, магазин Алюминий Кокчетавская 12 Харьков или в интернет магазине https://kzask.ua/ugolokrav/, вы также можете купить равносторонний уголок алюминиевый по цене производителя.
Первичный алюминий А0 (технической чистоты) поставляется по ГОСТ 11069-2001.
Магазин Алюминия предлагает: без покрытия 160х60х4.5 алюминиевый купить уголок https://goo.gl/maps/dQtFQEon34D2
Чушка алюминиевая, фото из Instagram. Хэштеги: #производство, #алюминий, #чушка. Аккаунт: @alyuminiy_com
Уголок равнополочный является сегодня довольно популярным материалом. С ним взаимодействуют во многих отраслях. Это обусловлено отменными эксплуатационными данными изделий: он прочный и в то же время легкий. Поэтому их все чаще можно увидеть там, где невозможно применение его аналога из стали.
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