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Scientists at the Kaiser Permanente Washington Research Institute in Seattle gave the first shot to the first person in a test of an experimental coronavirus vaccine Monday—leading off a worldwide hunt for protection even as the pandemic surges buff.ly/38TkwJZ
🐤 twitter.com/Rainmaker1973/stat

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“We find, under a linear regression framework for 100 Chinese cities, high temperature and high relative humidity significantly reduce the transmission of COVID-19“

papers.ssrn.com/sol3/papers.cf

🐤 twitter.com/DKThomp/status/123

The average number of "good quality air days" in China's province increased 21.5% in February, compared to the same period last year, as authorities ordered factories to close and residents to stay home to stop the spread of the coronavirus.
twitter.com/cnni/status/123979

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💊 We treat things by either imitating or blocking the post-ganglionic neurotransmitter.

💊 So, for instance, if we want to imitate a parasympathetic effect, we're going to give a drug that acts like acetylcholine, that acts like acetylcholine at muscarinic receptors.

💊 If we want to stop a parasympathetic effect, we're going to block a muscarinic receptor.

💊 So, things that act like a neurotransmitter are called agonists, and things that block the effects of neurotransmitters are called antagonists.

💊 Secretions are a very parasympathetic effect; we secrete stuff because we're going to go and try and digest stuff.

💊 And so, if we want to reduce secretions, we're going to try and block the effect of the muscarinic receptors. So, we're going to antagonize that muscarinic receptor.

💊 The group of drugs that we use, in general, to treat hypertension are called beta-blockers.
They're beta-blockers because they block the beta version of the adrenergic receptors (metabotropic receptors that receive information from norepinephrine are called adrenergic receptors).

💊 The drugs that act on the parasympathetic system either to mimic it or to block it, they stay peripheral.

💊 They have no effect on the brain other than an indirect effect.
They might make you feel dry, you'll get dry mouth, dry eyes, and that might make you, put you in a bad mood — but it's not a direct effect. They're not acting on the brain.

💊 In contrast, drugs that act on the sympathetic system tend to also have psychotropic effects, they also act in the central nervous system.

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🔴 Autonomic Pharmacology: Adjusting the PS/S System

🔸 Instead of as in the skeletal motor system where there's one motor neuron that goes and enervates a skeletal muscle, autonomic systems get to the target by two neurons.

🔸 The first neuron sits in the central nervous system. We call it the preganglionic motor neuron, and it contacts a motor neuron that sits in an autonomic ganglion.
And in both the case of the parasymptathetic preganglionic and the sympathetic preganglionic — they're both using acetylcholine.

🔸 So, all motor neurons use acetylcholine. And all motor neurons going to the post-synaptic target — whether it's the skeletal muscle or whether it's a ganglion cell — is going to express a nicotinic acetylcholine receptor. This is a fast ionotropic receptor — it's going to very instantly give a response.

🔸 The sympathetic preganglionic neuron goes to a ganglionic neuron which expresses this nicotinic acetylcholine receptor.

🔸 The parasympathetic preganglionic also goes to a ganglionic neuron that expresses a nicotinic acetylcholine receptor. And there, the two systems diverge.

🔸 In the parasympathetic system, we stay with acetylcholine as our neurotransmitter. The ganglionic neuron sends a post-ganglionic axon, which is an unmyelinated axon that goes to one of the three targets — smooth muscle, cardiac muscle, or gland. And it is going to release acetylcholine.

🔸 There's a difference between the release of acetylcholine at the terminal of ganglionic neuron and the release of acetylcholine at the terminal of post-ganglionic axon.
And the difference is that the targets (e.g.: smooth muscle) are always expressing as metabotropic (very slow) indirect receptors.

🔸 They're acetylcholine receptors, but they're muscarinic, as opposed to nicotinic.
Each of these targets is going to express a different muscarinic receptor. The effect is that the transmission is slow.

🔸 Now, in the sympathetic system, once we get to the ganglion, we switch to norepinephrine (NE).

🔸 So, norepinephrine is contained in the ganglionic neurons, and they send an axon, and again, an unmyelinated post-ganglionic axon that enervates one of the three targets — smooth muscle, cardiac muscle, or gland.

🔸 These receptors that receive the message of norepinephrine are also metabotropic, and so therefore, they are also slow.

🖼️ Image source: Screen grab from coursera.org/learn/neurobiolog

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🦠 The neuroinvasive potential of SARS‐CoV2 may be at least partially responsible for the respiratory failure of patients - Increasing evidence shows that are not always confined to the respiratory tract and that they may also invade the central nervous system
onlinelibrary.wiley.com/doi/fu

reddit.com/r/science/comments/

test: ICMR intensifies random testing to check for covid-19 - The Economic Times
m.economictimes.com/news/polit

Each of the 51 Indian Council of Medical Research (ICMR) laboratories is to test 10 such samples every week. The exercise began on March 15. Before this, the ICMR had picked up 20 samples and tested them at 13 labs to check for community transmission between February 15 and 29.

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