https://science.sciencemag.org/content/369/6503/510
This is an article from Science magazine about viruses and their cellular receptors. This is complex because various factors determine entry of substances into cells, like receptors and transporters, which are proteins. Proteins are encoded by genes, so a particular gene sequence regulates these receptors and transporters which control which tissues in the body are infected. We know that this virus infects various bodily tissues, and not uniformly. The article mentions the Spike protein, by which the virus latches on to the Angiotensin-Converting-Enzyme (ACE) 2 to enter cells. ACE2 also functions in things like blood pressure and inflammation. So there you go. This is a pretty technical article but worth getting through. The enzyme ACE (a different enzyme) performs a chemical function, changing the hormone precursor (not the active hormone) Angiotensin I to Angiotensin, which is an antagonist of Angiotensin II. ACE2 is balanced by ACE. Both ACE and ACE2 are highly present in the pulmonary (lung) endothelial cells and blood vessels. ACE2 is also expressed in the intestine, which explains some of the GI symptoms.
The article also goes into the deterioration that causes severe systemic COVID-19. And the immune system involvement in the disease. Immune-mediated damage might involve complement-activation, antibody-dependent enhancement or cytokine release or all of the above. The conclusion is always the same, and sadly not within reach at this point:
I quote: Therefore, it is essential to identify individuals with early SARS-CoV-2 infection who are at high risk of progression to severe disease, and test antiviral therapies to prevent viral entry and replication. It should not be too difficult to identify these “at risk” patients who are in danger of progressing to severe disease through contact tracing and testing, even prior to symptom onset.
https://www.nytimes.com/2020/07/30/health/covid-19-vaccine-monkeys.htmThis is an article by Carl Zimmer in the NYT about clinical trials which are proceeding with the J and J vaccine and one made by the Moderna company. An important quality of a vaccine is whether it protects from infection, which is called a challenge. And how long the protection lasts. There is no getting around the protection, but if the duration of the immunity is shorter than necessary, boosting the protection with a second vaccination is the usual course of events. The J and J vaccine uses a vector to carry the Spike protein gene into the body and there the gene makes the coronavirus proteins, which provoke an immune response. After a single injection of one vaccine, scientists waited for a week, then injected animals with the coronavirus and looked at the amount of protection offered. In 6 out of the 7 vaccines variants, partial protection was provided and the seventh was more powerful because no virus was detected in the challenged, vaccinated monkeys. J and J is advancing this seventh vaccine into a Phase I human safety trial, which is preliminary to the Phase III efficacy trial.
This is a NYT article about the warp speed fallacy. It is actually about how clinical trials' new audience seems to be Wall St, with the stock price of one small biotech company in Pennsylvania surging based on promising early results. The article points out that this same company announced "encouraging news" about malaria, Zika and cancer vaccines but has never brought a vaccine to market. Shares went up as much as 963%. Insiders trading on the stock, made a big profit. The vaccine needs to be administered by what sounds like a version of an electroporator, which moves DNA into cells. A 36-person trial was done in April, with reports that the vaccine was well-tolerated and generated an immune response. But no data was presented, meaning that there is no way to tell if it works to protect people against the coronavirus.
https://www.nytimes.com/2020/08/05/arts/design/bronx-virtual-tour.html This is an article from the NYT about the home of the Bronx Bombers in antiquity. Not in 1967, when I lived there; saw James Brown at the stadium as well as the bombers, ate ice cream at Addie Vallens. The Lenape name for the Bronx is Minnewits. The Bronx is the only part of NYC that is actually attached to the rest of North America (Manhattan and Staten are islands, Brooklyn and Queens are part of Long Island.) The article format is interview with Eric Sanderson, senior conservation ecologist of the Wildlife Conservation Society, who holds my ideal job and is based at the NY Zoological Gardens. To those of my audience who remember the Yanks' transit from the Polo Grounds in Manhattan across the Hudson, salutations. Mr. Sanderson quotes a paper (unnamed) which speculates that during the Pleistocene Era, about 1.5 million years ago, the Hudson River flowed the path of what is now the Harlem River, not along the west side of Manhattan, past the future Polo Grounds and Yankee Stadium, through Flushing Meadows, and carved out the valley under Jamaica Bay. Later glaciations rearranged everything. The interviewer's conclusion is that the city's rivers, like its inhabitants, have changed neighborhoods and assumed new identities.
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