Covid-19 [4]
A World War 2 Trilogy - By FRED NATH (Novelist and Neurosurgeon)
RSS Follow Become a Fan

Delivered by FeedBurner


Recent Posts

Covid-19 [5]
Covid-19 [4] The NHS
Covid-19 [4]
Covid-19 [4]
Covid-19 [3]

Most Popular Posts

Fred's Doc Blog
The Trial by Franz Kafka -my personal view.
Dr Bawa-Garba and Manslaughter
How to self-publish your book (Episode 1) - a Quick, Easy Solution!
Trigeminal Neuralgia

Categories

Entertainments
Food
Grumbles
Medical stuff
news
Politics
thoughts
Writing

Archives

May 2020
April 2020
March 2020
July 2019
June 2019
February 2019
January 2019
December 2018
May 2018
April 2018
February 2018
December 2016
September 2016
June 2016
May 2016
April 2016
January 2016
November 2015
August 2015
March 2014
January 2014
May 2013
April 2013
March 2013
October 2012
September 2012
August 2012
June 2012
May 2012
April 2012
March 2012
February 2012
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010

powered by

Fred's Blog

Covid-19 [4]

Virology half-understood, pseudoscience and and maybe a little hope:
Coronaviruses are interesting. They have the biggest genome of any RNA viruses in their nucleocapsid (the envelope with the RNA in). There are three proteins – S- or spike protein which makes up the spikey part on the outside, M protein which makes up the outer membrane and N protein which encloses the nucleocapsid inside.

The virus spreads in two ways. It can force replication of its own RNA and the new virus particles exit the cell emerging into the extracellular space to infect other cells. The other way it moves to new cells is by syncytial spread – moving through cell membranes into adjacent cells. The ‘clever’ part about that is that it can spread along a mucosal (lining membrane) surface without ever being exposed to the extracellular environment where antibodies (IgG and IgM) can neutralise it, or extracellular toxins (like drugs) can affect it.

The virus has an affinity for a particular site on human cell membranes called angiotensin converting enzyme-2 or ACE-2 receptors. That receptor is common and present on many cells in the body. The purpose of ACE is to increase levels of angiotensin which is important in the renin/angiotensin mechanism (which keeps your blood pressure up). This renin angiotensin pathway raises blood pressure by causing vasoconstriction. Inhibitors of ACE can occupy these receptors on cells and work by causing smooth muscle relaxation and lowering of blood pressure. 

The Coronavirus spike protein latches onto that receptor site and changes shape to allow passage of the nucleocapsid into the cytoplasm of the infected cell, where is latches onto the Golgi apparatus and creates replicas of its own RNA. Unfortunately giving ACE inhibitors doesn’t prevent viral attachment because the spike protein can change the morphology of the receptor site to adapt.

Potentially the only way to affect the virus is during replication or to block the exiting particles.

Chloroquine affects the developing malaria parasite by blocking one locus on the protein necessary for it to exit the red blood cell it infects. Since Coronaviruses have a large complex RNA chain and require certain proteins to burst out of the host cell there must be some logic in using Chloroquine to damage those proteins.

Similarly, bacteriostatic antibiotics (Doxycycline, Azithromycin) inhibit protein manufacture by acting on a different locus on mycoplasma proteins (the antibiotics of choice for Chlamydia) and prevent the infected cell from letting out the infecting organism.

So, my feeling is to treat the infection as early as possible with those two drugs, so the extent of the infection is reduced and hopefully the second phase of the illness won’t occur. This is unproven but there was one small study, poorly controlled and much criticized which did show that patients on these two drugs did better than patients who did not take them, albeit in a different hospital but otherwise age and illness matched.

I think that if/when I get this virus, I want early treatment with those 2 drugs!

0 Comments to Covid-19 [4]:

Comments RSS

Add a Comment

Your Name:
Email Address: (Required)
Website:
Comment:
Make your text bigger, bold, italic and more with HTML tags. We'll show you how.
Post Comment