36 replies to this topic

[JMorgan]

Has anyone actually ever revived anything that has been frozen other than a single-celled organism?

I'm very optimistic, but also skeptical. I'd like to see some bigger advances before spending so much on something like this. I'd feel much better if I knew there was at least SOME progress in the present day.

[kraemahz]

Entries in PubMed on vitrification:
http://www.ncbi.nlm....4&dopt=Abstract
http://www.ncbi.nlm....t_uids=15094092

In the first is the successful devitrification of blood vessels, the second about rabbit kidneys.

[Matt]

Im not sure if its actually necessary to totally stop aging. At first we could repair using Stem Cells. We are bioligical at the moment so trying to completely stop aging is not something that is realistic, yet.

Reversing damage is totally realistic scenario, As a person ages they get more diseases, Through these diseaes and organ failiars come death. By say repairing the heart to 100% health you eliminate death caused by heart problems, Therefor you are extending the life of the person. By repeating the same process to other vital organs in the body you continue to Extend the life span and you repeat the process when you need a top up...

First of all we are going to require some pretty advanced Nanotechnology to repair damage straight away for the patient. When this kind of technology comes about we could alter humans in so many ways and repair damage " on the fly "

For true Immortality I dont see us exactly being " human " you would have to re-design the human body.

I see this being a possibility through technologies such as

nanotechnology
Biotechnology
Robotics
computer science, Neural-Computers

[Matt]

Also about revival. Im sure that people are revived after atleast an Hour after they had died and their Brain had STOPPED functioning and heart stopped. because they were extremely cold it slowed down damage.

So people have been brought back from what some people would call " death "

[jaydfox]

So if we do get this very good method of freezing without causing the fractures then how much difficult would it be to revive someone.

I mean if you good could thaw the person and repair the thing that killed you AND repair the brain if any minor damage...

(my emphasis added)

Don't forget that you also need to reverse the embalming process used in vitrification. Most tissues are subject to something like a 60% solution of chemical cocktails, meaning less than 40% of the person's tissue mass will be water. I'm not a biologist, but I'm pretty sure that those chemicals are highly toxic at room temperature, insofar as they interfere with normal cellular biochemical processes.

So I don't think it's as simple as thawing. There's a detoxification step involved.

[bgwowk]

cosmos wrote:

I've heard about the fracturing problem. I think cryonicists are aware of that as well, but it's still preferable over non-fractured glycerol preservation. ALCOR may soon correct the fracturing problem, anyway.

There is a persistent myth that fracturing is a problem unique to vitrification. Fracturing was first discovered in frozen (not vitrified) patients decades ago. It just wasn't talked about much because freezing damage is so much worse. Fracturing is getting more attention now simply because the vastly improved structural preservation of vitrification is moving fracturing up the "to do" list of remaining problems to eliminate.

malciah asked:

Has anyone actually ever revived anything that has been frozen other than a single-celled organism?

Certainly. See http://www.alcor.org/sciencerefs.html

It both and amuses and frustrates me to see frogs so frequently cited as an animal that can be "frozen" and then revived. Yes frogs can be cooled below 0 degC, forming ice in some of their tissue spaces, and then still survive. But most of their body is still a thick fluid, not solid. They would not survive cooling to far below 0 degC because they would not survive the overwhelming amounts of ice that would form. So they cannot be "frozen" indefinitely.

I note that if survival after cooling to high sub-zero temperatures qualifies as "surviving freezing", then whole mammalian brains have been shown to "survive freezing" (even freezing for years) per the references above.

jaydfox wrote:

Don't forget that you also need to reverse the embalming process used in vitrification. Most tissues are subject to something like a 60% solution of chemical cocktails, meaning less than 40% of the person's tissue mass will be water. I'm not a biologist, but I'm pretty sure that those chemicals are highly toxic at room temperature, insofar as they interfere with normal cellular biochemical processes.

So I don't think it's as simple as thawing. There's a detoxification step involved.

This is correct. Interference with biochemistry by unknown mechanisms, possibly protein denaturation, is currently the main obstacle to real-time reversible vitrification of brains or any large mammalian organs. Yet the solutions and protocols now used by Alcor are tantalizingly similar to the protocols used for real-time reversible deep cooling experiments in rabbit kidneys and brain slices, suggesting that whatever "hits" are occuring may be minor.

Of course, even once real-time reversible brain cryopreservation is perfected, you then have to either preserve or replace everything else before anyone could be revived. Demonstrably reversible cryonics is still a LOOOONG way off. But once brain preservtion is perfected, then at least you know that on a technical level it's guaranteed to work.

---BrianW