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Alzheimer’s cases tied to no-longer-used medical procedure

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191–200 of 247 posts

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#191
post #137

Earlier quoted context omitted.

They still use pieces of cadaver for other surgeries. E.g. gum and bone transplants done by periodontists. Seems risky to me.

as long as it’s not spine or brain matter it’s probably okay. During the mad cow outbreak (BSE, the bovine equivalent of CJD) in the UK, they banned “beef on the bone” but not all beef.

And CJD came about from farmers using ground and processed cow brains to feed cows. What could possibly go wrong feeding a cow some cow brains!

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#192

Sounds like a sensible next step would be to try and replicate this in animal models (i.e. treat animals with growth hormones extracted from cadavers of same species) to identify the proteins/prions that trigger the pathogenesis of Alzheimer's, which could perhaps be drug targets for at least a subset of AD causes.

For CJD the testing isn't needed, it is established that cows eating processed cow brains caused the outbreak.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#193
post #4

My understanding was the beta-amyloid hypothesis itself is under some amount of scrutiny and may not truly explain Alzheimer's. Wonder if this finding adds more evidence for the amyloid hypothesis.

The short version as I understand it: amyloid plaques are a symptom but not a cause.

There was a theory floating around that they're a neurological immune response to viral infection but I don't think there's enough evidence to prove that yet.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#194
post #8

Afaict, this is not an entirely new finding. For example, this page ( https://www.nature.com/articles/d41586-018-07771-6 ) references a 2018 article about the issue of Alzheimer's being transmitted (or rather "seeded") through growth hormone extracted from cadavers. Perhaps the new article provides additional evidence or perhaps the other article only suspected a casual link and this one proves that there is one. I h…

Both new and old articles are from the same lab. So they hypothesized it in previous article and now found signs of dementia in some of patients who survived. Still no evidence of actual transmission of A-Beta.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#195

I wonder what other stuff is being unwittingly transferred during standard blood transfusions. I've seen some interesting research about the "signalling" power of blood from both older and younger donors, with the "young blood" causing a slow down of senescence in cells, and the "old blood" causing a speed-up in senescence. Any time you take biological material out of other human beings and put them in a different bo…

There is no evidence of actual transfer. It is just a possibile hypothesis.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#196

Earlier quoted context omitted.

as long as it’s not spine or brain matter it’s probably okay. During the mad cow outbreak (BSE, the bovine equivalent of CJD) in the UK, they banned “beef on the bone” but not all beef.

And CJD came about from farmers using ground and processed cow brains to feed cows. What could possibly go wrong feeding a cow some cow brains!

It is worse than that - it first made the jump to cows when condemned sheep, infected with the similar prion disease 'scrapie', were ground up and fed to cows.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#197

Earlier quoted context omitted.

You are supposed to declare your issues before (or at least after) you give blood. Kinda messed up that whoever donated that blood didn't report it. Then again, I'm glad the blood was available...

We can't conclude that the donor had an egg allergy. The immune system is complicated as hell, it could be the case that he had some weird protein circulating on his blood that was recognized by her immune system, and by chance this protein was structurally close enough to some egg protein that now eggs trigger an immune response on her.

"The immune system is complicated as hell."

You got that right! My wife used to eat a banana every day. Then something in her flipped and she reacts as if she is allergic to bananas and the rest of the world - not exaggerating. She can eat a very small number of foods and has to avoid most people because of smells. It isn't allergies it is - you guessed it - her immune system.

If we could just flip it back to "normal"...

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#198
post #171

Earlier quoted context omitted.

Killjoy note that the allergy may well be unrelated to the transfusion, despite occurring after it.

Though it seems quite plausible something in the blood caused an immune reaction that then also gets set of by egg protein.

FWIW, ChatGPT 3.5 says:

"The development of a new food allergy, such as an allergy to eggs, as a direct result of a blood transfusion is extremely rare and not a well-documented phenomenon. Food allergies are typically triggered by exposure to specific allergenic proteins found in foods, and blood transfusions do not typically involve the introduction of food proteins."

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#199

Earlier quoted context omitted.

as long as it’s not spine or brain matter it’s probably okay. During the mad cow outbreak (BSE, the bovine equivalent of CJD) in the UK, they banned “beef on the bone” but not all beef.

And CJD came about from farmers using ground and processed cow brains to feed cows. What could possibly go wrong feeding a cow some cow brains!

There's a human prion disease, kuru, which was caused by the practice of funerary cannibalism - where family would ritually consume parts of their deceased relatives' bodies.

The moral of the story seems to be, don't eat brains.

Re: Alzheimer’s cases tied to no-longer-used medical procedure

#200

I wonder what other stuff is being unwittingly transferred during standard blood transfusions. I've seen some interesting research about the "signalling" power of blood from both older and younger donors, with the "young blood" causing a slow down of senescence in cells, and the "old blood" causing a speed-up in senescence. Any time you take biological material out of other human beings and put them in a different bo…

>Any time you take biological material out of other human beings and put them in a different body, it seems like you are introducing a lot more uncertainty and risk But this always had to be weighed against the risks of not getting the transfusion. Typically the consequences of not getting a transfusion when it is medically indicated is pretty severe. We don't really need to worry about unlikely not-yet-understood ed…

Depends what the indication is, for some kinds of trauma the evidence is that transfusions are what will keep the patient alive, e.g. you're dumping pints on the table and it's likely to be contaminated, you can't salvage and reinfuse. However, for pre-planned surgery the evidence suggests avoiding blood loss where you can is the best practice. Studies have also shown that pre-deposit autologous blood donation before surgery is of uncertain benefit so it tends to be contra-indicated in the UK at least.

Before we understood the risks we used to do transfusions a lot more frequently than we do now and this led to a generation of anaesthetists who would basically treat with blood transfusion at the slightest sign of low blood count. More recent studies have suggested that a lower blood count can be tolerated than was previously realised and that you can often get away with guaranteed pathogen free (and much cheaper) volume expanders. There has also been developments in cell salvage to reinfuse suctioned blood and methods to avoid blood loss in the first place.

Medical practice has also changed to reflect this and the changed evidence base, especially given the relative costs (hospital managers love to save money). Hip and knee replacement surgery used to use blood routinely and were almost always done under general anaesthetic, but given we now want to get patients out within a day or two post surgery we do the surgery under spinal block and minimise blood loss as much as we can.

tldr; We still need transfusions for some things but we should be using them less than we do.

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