Wikipedia:Reference desk/Archives/Science/2018 May 14

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May 14

Route of administration of aspirin

When does it make sense to administer aspirins through the rectal route? It is harsh on the stomach, but despite this, I haven't ever heard of anyone taking them this way.--Hofhof (talk) 00:18, 14 May 2018 (UTC)

When the patient can't swallow, or has other issues with oral administration. See rectal administration. It could also be administered intravenously, but any IV intervention carries risks; you don't want to put in an IV just for some aspirin. (Note: I believe this question is fine for the ref desk. It's not asking how to diagnose or treat something.) --47.146.63.87 (talk) 01:11, 14 May 2018 (UTC)

Aspirin is harsh on the stomach, but this is caused by the aspirin in the blood; some of this will enter the cells of the stomach well where it knocks out certain enzymes that protect the stomach wall against stomach acid. Count Iblis (talk) 02:09, 14 May 2018 (UTC)

I've previously read that the route has a strong cultural component as well. Rectal medications are strongly selected against in North America, for example. (Ref). I can confirm from experience (I have a kid who never learned to swallow pills) that adult-strength painkillers are essentially only available to the public (in Canada, at least) in oral pill/tablet form - no syrups, suspensions, or suppositories. Matt Deres (talk) 18:58, 14 May 2018 (UTC)

The increased risk of gut bleeding still occurs with the rectal route], so that doesn't solve the problem. Klbrain (talk) 21:53, 14 May 2018 (UTC)

Does monoamine oxidase inhibitors not change the level of acetylcholine?

I was told that monoamine oxidase inhibitors does not change the level of acetylcholine but I'm not sure about that because this site states that "monoamine oxidase, an enzyme that has a key role in the metabolism of the monoamine neurotransmitters acetylcholine, dopamine, epinephrine, norepinephrine, and serotonin." and it seems that it does change its level. Isn't it? 2A02:ED0:6F01:8600:154E:FD5:6431:60CA (talk) 12:53, 14 May 2018 (UTC)

I think that site is in error. Acetylcholine is not a monoamine and is not metabolized by MAOs. There will be some indirect effects, because levels of those other transmitters affect the release of acetylcholine, but there should not be any substantial direct effect. Looie496 (talk) 14:14, 14 May 2018 (UTC)

Agree that that site is in error; acetylcholine doesn't have the aromatic ring which is a defining feature of the monoamine neurotransmitter. Also the Guide to Pharmacology doesn't list it as a monoamine oxidase substrate. Klbrain (talk) 21:38, 14 May 2018 (UTC)

Definition of protein complex

If a single protein associates with RNA (like Cas9) can that be called a complex or is a complex only something comprised of multiple proteins (the article suggests the later but I wanted to be sure) 129.215.47.59 (talk) 17:18, 14 May 2018 (UTC)

That would be called a nucleoprotein complex. Someguy1221 (talk) 17:31, 14 May 2018 (UTC)

What sets the northern limit of spring-ripening barley of the Passover-postponement rule phenotype?

I've heard it's not very winter-tolerant. How deep would the snow cover or cold have to get to kill it (or at least prevent it from ripening in the Jerusalem manner?) How much liquid precipitation would it need? (applicable to very continental farming areas) Could you grow it that way in like Bowash or Ireland or is there not enough sun? Sagittarian Milky Way (talk) 20:00, 14 May 2018 (UTC)

Haven't been able to answer directly but see:-

• The Timing of the Barley Harvest in Israel, a comparison of Biblical and modern barley farming.
• THE ISCA GRAIN, A ROMAN PLANT INTRODUCTION IN BRITAIN describes finding barley grains which "...may be classified as belonging to a six-row spike {Hordeiim vtdgare L.)" amongst other cereals datable to A.D. 80-130 in Wales, (a climate very similar to Ireland).
• Ancient barley DNA gives insight into crop development: "An international group of scientists have analysed the DNA of 6,000 year old barley [found by the Dead Sea] finding that it is remarkably similar to modern day varieties".

Alansplodge (talk) 22:26, 16 May 2018 (UTC)

Of course barley might be a summer crop in Wales instead of winter like Israel. Sagittarian Milky Way (talk) 23:16, 16 May 2018 (UTC)

It is a winter crop in Wales now, but in Roman times, who knows? Alansplodge (talk) 17:35, 17 May 2018 (UTC)