Eugene.Leitl at lrz.uni-muenchen.de
Wed Sep 4 05:08:33 EST 1996
On Mon, 2 Sep 1996, john wrote:
> Yes it probably is oversold I believe.
> But since so many items from blood to whole living mammals have been stored for
No large biological system, "whole living mammals" set apart, has ever
been restored to living condition from cryosuspension, even transiently.
According to Suda's (a 1966 "Nature" paper?) _unconfirmed_ experiments,
glycerolyzed cat brains stored for several months under
unfavourable conditions regenerated artefacted EEG upon defreezing (_not_
vitrification) & reperfusion with feline blood. By today's standards, the
experiments were crude. If any cryobiologist is reading this, his
comments upon the original experiment would be highly appreciated.
Freezing nematodes & other hardy microcritters cannot be equaled to
cryopreservation of large, anisotropic biosystems. The best one can hope
for, is low-damage reversible vitrification of singe _organs_, e.g.
kidneys for transplantation medicine. Though there has been some progress
in this direction, it has not yielded a full success yet.
Cryonics does _not_ say the cryopreserved system to be viable upon
devitrification sans heavy nanoreconstruction. Should nanotechnology be
impossible, then cryonics is patently impossible (ignoring here more
arcane scenarios as uploading, etc.).
> longer than any accidental apparently dead person has, it must have some
> probability of working on humans in the future.
We have to assume a nonfinite probability does indeed exist, though no
reliable estimate is possible, of course. (Only religion offers comfortable
absolute statements, alas).
> In the realisation time of the incurable cause of death of anyone, this option
> competes for financial savings in a rational way, though I feel the normal
> disposal of estates are still more justified.
According to some trivial theories, evolution has artefacted a
mental reality filter for some events as e.g. propagation and death. This
hypothetic filter is thought to a) suppress reasoning about own death b)
by raising strong negative emotions in the face of death or its discussion.
(A tentative corollary of this is the fact that belief in an afterlife
is the basis of virtually all cults, all over the globe).
In the majority of the populace this hypothetic filter renders all
rational discourse about death, especially one's own death, impossible.
The discussee is often subjected to intense hostility, i.e. ad hominem
reasoning. It would be interesting to test, whether such a filter really
exists. A psychologist could cook up an experiment to (dis)prove this
quite easily, obviously.
> Most important of all is it makes people look further to the future in this
> fast evolving world than anything else.
Well, at least one single positive thing. Liquid nitrogen's cheap.
Spinoffs for both transplantation and IC medicine (e.g. liquid ventilation
CPR) & cryobiology are on record. Even if cryonics should prove itself
inviable, the overall result should be positive.
What's the problem, then?
> The individual considers pension and then will, but now the posibility of a
> life time after death.
> Its your money so its your bet for a better world.
Right. Just I ask for is rational discussion. Afraid of a mere taboo?
Willing to expose obvious kookery?
To avoid alienation of hard scientists, which patience has been sorely
tried indeed, I propose to move all followup to sci.cryonics. Thanks.
-- Eugene Leitl
P.S. One single thing: does anybody in here do SPM (AFM) of vitrified
neural tissue in vacuum (freezefract, sublimation etch) under cryogenic
conditions? Has anybody tried excimer pulses for complementary
photolytic etch? Results?
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