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Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

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Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#21

Post by arkades »

fallingknife wrote: post #18
arkades wrote: post #10

Prion disease is exceedingly rare. CJD is the most common, with an incidence of 1 per 1,000,000 person-years worldwide, inclusive of all transmission vectors (including medical procedures). Iatrogenic transmission is a rarer subset still: the riskiest transplants (with respect to CJD) are in the central nervous system. The UK tracked their transmission rates from 1970 to 2003 (a long period is needed because surgical…

Infectious disease is one area where fear of the unknown is rational. We don't just need to defend against existing diseases, but also diseases yet to emerge. Just because CJD is rare doesn't mean that the next prion disease will be, so it would make sense to take measures to prevent transmission of prions now.

We take measures now, for tissues where prions are a possible transmission risk. The article mis-represented that. But:

(1) there are only so many resources to go around. Should we be devoting them to vanishingly rare things rather than things that might actually affect you?

(2) prions will never be a wildfire plague. They have little or no tranmissive ability, by nature of being absolutely naked protein. One step up from that - encoding the protein for space constraints and encapsulating it - is called a virus.

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#22

Post by Grazester »

barking wrote: post #7

About 20 or so years ago I was feeling bad about my chances of developing the type of CJD associated with mad cow disease because of all the burgers I'd eaten over the preceding years. There were also human cases getting reported at a rate that some suggested matched the pattern for the early days of an epidemic. Luckily that never materialised. Still though having lived in the UK during a certain time period preclud…

I stopped eating beef from that time due to that mad cow outbreak. A few years before that I was worrying about the Ebola outbreak in Zaire. I was no where near these regions either. As kid and into my teens I was pretty paranoid about disease and death.

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#23

Post by ryanmercer »

AllegedAlec wrote: post #19
ryanmercer wrote: post #14

Prions are one of the things that makes me go, hey wait maybe we do live in a simulation. They're basically corrupted code (which we've yet to figure out how they get that way in the first place) that corrupts other code... what is that?!?! Reminds me a lot of the WoW 'corrupted blood incident'. I understand how something like bacteria or a virus enters a host and replicates, but an anomalous protein corrupting other…

It's actually relatively simple. Proteins, very roughly speaking, are things that change other things into something we need. You could think of proteins required for breaking down sugar, which do more or less exactly that: they take a molecule of sugar, break a part off of it and hand it to the next protein in the chain. What makes prions so weird is that they are a protein that has been mismade (misfolded, generall…

>What makes prions so weird is that they are a protein that has been mismade (misfolded, generally).

And science doesn't know how they get misfolded in the first place then they basically go "hey other protein, boop you're like me now, let's burn this mother to the ground" and then you get something similar to the 'corrupted blood incident' https://en.wikipedia.org/wiki/Corrupted_Blood_incident except you lose your mind and die.

As far as saying we know how proteins misfold, I'm going purely by what I've read both on and on wikipedia as I'm not an expert in proteins and amino acids...

>It is not known what causes the normal protein to misfold

Second sentence of: https://en.wikipedia.org/wiki/Prion

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#24

Post by OldFatCactus »

I had project in college on Prions. Some interesting things I remember:

* Kuru (laughing disease) was transmitted from cannibalism. Women and children of the tribe were more likely to contract it because they were more often given the less palatable parts of the bodies, which included brains

* Some countries do not trust American cattle because our standards for Prion screening are too low

* Kentucky has issues with Prions because Squirrel brains are a popular dish

Try not to eat animal or human brains and you can dramatically reduce your chances of getting Prions

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#25

Post by ryanmercer »

mrob wrote: post #20
ryanmercer wrote: post #14

Prions are one of the things that makes me go, hey wait maybe we do live in a simulation. They're basically corrupted code (which we've yet to figure out how they get that way in the first place) that corrupts other code... what is that?!?! Reminds me a lot of the WoW 'corrupted blood incident'. I understand how something like bacteria or a virus enters a host and replicates, but an anomalous protein corrupting other…

At the molecular scale, everything is effectively made of springs (molecular and intermolecular bonds). Proteins are a big complicated tangle of springs, and that means they have multiple possible configurations they can spring to if you let them relax. If you bump another protein of the right shape against them, you can nudge them into a different spring configuration. Think of "slap bracelets", those curved metal s…

>Think of "slap bracelets", those curved metal strips that spring around your wrist

Wow, I've not heard someone mention those in probably 2 decades.

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#27

Post by sandworm101 »

fallingknife wrote: post #18
arkades wrote: post #10

Prion disease is exceedingly rare. CJD is the most common, with an incidence of 1 per 1,000,000 person-years worldwide, inclusive of all transmission vectors (including medical procedures). Iatrogenic transmission is a rarer subset still: the riskiest transplants (with respect to CJD) are in the central nervous system. The UK tracked their transmission rates from 1970 to 2003 (a long period is needed because surgical…

Infectious disease is one area where fear of the unknown is rational. We don't just need to defend against existing diseases, but also diseases yet to emerge. Just because CJD is rare doesn't mean that the next prion disease will be, so it would make sense to take measures to prevent transmission of prions now.

It is also an are where our innate fears, fears that modern society tells us are unacceptable, might have a place. There is a deep-seated fear of diseased people that once kept us healthy. Modern science has given us an understanding of disease that means there is often no need to physically separate paints where we know the disease is not easily transmitted. The shunning of an aids victim, or a child with cancer, is totally unacceptable in polite society. But prions, and especially research into possible links to various forms of dementia, suggest some dark futures. Maybe it isn't a great idea for the kids to visit grandma in hospital.

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#28

Post by hannasanarion »

ryanmercer wrote: post #14

Prions are one of the things that makes me go, hey wait maybe we do live in a simulation. They're basically corrupted code (which we've yet to figure out how they get that way in the first place) that corrupts other code... what is that?!?! Reminds me a lot of the WoW 'corrupted blood incident'. I understand how something like bacteria or a virus enters a host and replicates, but an anomalous protein corrupting other…

But prions aren't code. DNA is code. Proteins are factory robots, and the prion protein is a factory robot involved in the process of making factory robots.

Neural proteins are very complicated, so they need other proteins to help them fold properly. One of these protein-folding-proteins (PRNP) can be mis-folded in such a way that it mis-folds other proteins in the same way that it is mis-folded itself.

When most factory robots break, they simply stop working and they get recycled. But when a robot-making robot breaks in just the right way, it starts producing robot-making-robots that are broken just like itself.

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#29

Post by lolc »

ryanmercer wrote: post #14

Prions are one of the things that makes me go, hey wait maybe we do live in a simulation. They're basically corrupted code (which we've yet to figure out how they get that way in the first place) that corrupts other code... what is that?!?! Reminds me a lot of the WoW 'corrupted blood incident'. I understand how something like bacteria or a virus enters a host and replicates, but an anomalous protein corrupting other…

Protein chains are used by all living cells to manufacture the molecules we're made of. They arrange soure material into new molecules. Many proteins are intended to manufacture themselves. This capability is usually tightly regulated by availability of the source materials within cells.

Prions are proteins too. And they can create themselves from source material too. But their source material are proteins which are not intended for processing. As such, prions are defined like weeds in a garden: They're not supposed to be there.

Marvel at the wonderful world that is biology: https://en.wikipedia.org/wiki/Protein

Re: Prions, Nearly Indestructible and Universally Lethal, Seed the Eyes of Victims

#30

Post by Balero »

ryanmercer wrote: post #23
AllegedAlec wrote: post #19

Earlier quoted context omitted.

It's actually relatively simple. Proteins, very roughly speaking, are things that change other things into something we need. You could think of proteins required for breaking down sugar, which do more or less exactly that: they take a molecule of sugar, break a part off of it and hand it to the next protein in the chain. What makes prions so weird is that they are a protein that has been mismade (misfolded, generall…

>What makes prions so weird is that they are a protein that has been mismade (misfolded, generally). And science doesn't know how they get misfolded in the first place then they basically go "hey other protein, boop you're like me now, let's burn this mother to the ground" and then you get something similar to the 'corrupted blood incident' https://en.wikipedia.org/wiki/Corrupted_Blood_incident except you lose your m…

There are plenty of ways that a protein could be mis-folded. There is a lot of bumpiness in a cell (though this is unlikely to lead to this). A random mutation (through some sort of radiation) could change a piece of DNA or RNA, causing the protein to be made incorrectly. All of these are frighteningly unlikely. But happen so often they are almost certain to do so in a large enough time, with a large enough population.

The similarities to the 'corrupted blood incident' start and end with them both spreading to others in a local area. Prions don't really suggest that life is a simulation.

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