I have finally read through most of/browsed the remainder of
the technical articles by Mike Darwin (BPI Tech Briefs #002/#4)
I agree that the articles are seriously written and for the most
part technically accurate (a little dated perhaps). However the
articles fail to comment in any serious way on the issue of what
can or cannot be repaired by serious nanotech (which is what Ralph
and a number of others argue will inevitably be required to reanimate).
As Mike points out in BPI Tech Brief #4, regarding the injuries
caused by cerebral ischemia, there are a host of problems that
occur when the brain becomes deoxygenated/deglucose-ylated.
The complexity of these problems is very large and you are
unlikely to have single individuals who can "grok" the entire
range of possible damages (and solutions). Solution: Cryonicists
should establish a network of individuals, each of which is *the*
expert on the state of the art with regard to various pathologies
(calcium influx, free radical damage, mitochondrial swelling,
neutrophil activation, ice crystal deformation, etc.). Only if
you have individuals who are expert in these areas who are able to
converse regularly will you begin to see progress in pre &
post-suspension methods.
I'll emphasize this point by observing that Mike's concerns about
arachidonic acid and iron might be dealt with by aspirin and
desferoxamine respectively.
However, the only thing I saw in the entire discussion which
raised warning flags for me was the destruction of the lysosomes.
While ice crystals may disrupt molecules and their locations, they
would tend to retain mirror image structures that allow reconstruction.
Everything else discussed (chromosome rearrangements, extracellular
matrix changes, mitochondrial swelling, etc.) can be repaired with
the exception of damage caused by uncontrolled lysosomal enzymes.
Lysosomal enzymes will fundamentally cause information loss.
They dismantle proteins and rearrange structure in such a way
that it may not be possible to reconstruct the original architecture.
To my mind, that implies that the fundamental requirement for
cryonic reanimation is not CPR for oxygenation or cryoprotectats
for reducing freezing damage, but lowering the temperature of the
brain to reduce the activity of lysosomal enzymes and/or adding drugs
to completely inhibit them.
You have to look at it this way -- If I break your mirror into
a zillion "relatively" unique pieces, I will still be able to
reassemble your mirror exactly the way it was orginally. On the
other hand if I disassemble your mirror into a zillion "identical"
molecules, I will likely never be able to reassemble it the way
it was orginally. I may be able to produce a functional equivalent
of what was there originally, but it will not be an original.
Of course these approaches beg the issue of exactly what it is
that people undergoing cryonic suspension are trying to preserve.
That is something, I suspect, is less examined than some might
argue would be desirable.
John, feel free to repost this to cryonet.
Robert
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