Re: Is cryopreservation a solution?

From: Geoff Smith (geoffs@unixg.ubc.ca)
Date: Sun Sep 14 1997 - 20:15:28 MDT


On Tue, 16 Sep 1997, Joao Pedro wrote:

> Hi!
>
> Geoff Smith wrote:
> > > I'm no zoologist, I'm graduating in Microbiology
> >
> > me, too, again. What university?
> >
>
> I study at the College of Biotechnology, Oporto, Portugal,
> http://www.esb.ucp.pt/texto/index.html
>
> What about you?
>

University of British Columbia, Vancouver, British Columbia, Canada,
http://www.ubc.ca/
 
> > > and, as far as I know,
> > > adding cryoprotectants (glycerol or dimethylsulfoxide mostly) is
> > > necessary to preserve microorganisms at very low temperatures. They act
> > > by preventing the formation of water crystals.
> > > There are indeed complex species (such as some frogs) that can survive
> > > freezing, they do so by producing a cryoprotectant and then spreading it
> > > through the body.
> > > Our case is much different, first because we are obviously much more
> > > complex than any microorganism or even than a frog.
> >
> > That's not a reason, silly!
>
> It ends up being, indirectly, one. Errors occur and since we are more
> complex the chances of errors occurring increases. How many times have
> you heard of therapies that work fine 'in vitro' and in monkeys and
> don't work in humans?

This is not *necessarily* an issue of complexity, just difference. We
will know how different/similar we truly are only when/if we adapt the
frogs method of freezing-tolerance to human beings. I'd say the jury is
still out.

> Just our brain, is so much more advanced than a
> frog's that the possibilities of errors are incomparable.

I would replace "incomparable" with "significantly larger." Otherwise,
I'd agree with this statement.

> There might be
> types of cells in our bodies that doesn't exist in frogs and that will
> not freeze the same way as the other cells.
> An increase in complexity always increases the potential of errors. BTW,
> that is one of the reasons why aging occur in complex animals such as
> mammals and doesn't occur in primitive species such as sharks.

Let us examine a specific case of genetic error, cancer:

Would you say that the reason sharks don't get cancer is because they
have a simple genome? Firstly, I'd have a hard time calling sharks
primitive. I would, however, call a number of plants primitive, all of
which have been known to develop tumors. As human beings, we have a more
complicated and prone-to-error genome, but we also have more
sophisticated ways of dealing with these errors-- apparently, so do
sharks.

I have another quibble in the form of a question: can you think of an
organism more primitive than a shark that DOES age?

All this said, in principle, I agree with what you're trying to say.

 IMHO,
> their evolution lead them to correct the errors in their genome while
> our evolution made us consecutively more complex

Are you saying their evolution *did not* make them consecutively more
complex?

> and therefore more
> susceptible of having genetic errors or lethal genes. For more see my
> next message which is mainly about the evolution of aging.
>
> > What's the difference between altering you current brain and genome, and
> > transferring to a new one? Is there something special about the neurons
> > that nature gave us? And if they're so special, why don't you leave
> > them the way they are? I'm not so attached to them. As long as I can do
> > all the same things with my new consciousness-vehicle(or more things), why
> > should I care whether I've got organic axons or metal ones?
>
> Transferring? Transferring what? Your brain? Your 'soul'?

The functioning and abilities of my brain. I would call this
"consciousness" Some might argue with my use of this word.

> One idea (that I already though about years ago) is to increase the
> viability of our neurons with metal or whatever but this is a continuos
> process. Just like now, the atoms that compose my neurons are not the
> same that were a few hours ago, exception made to some molecules such as
> DNA, our neuron's atoms change continually and I don't complain.
> Connecting memory chips to our brain might not be a bad idea but that is
> a change and not a transfer.

If your brain ends up in the same state after a series of "changes" or one
single transfer, what, exactly, is the difference?

The only difference I can see is simply one of safety: if the changes
start to suck away your conscious thought, you know your uploading process
is not working, and you can stop before you have changed your entire brain
into a less fragile form. I will opt for this method if it is available.
It is still uploading, however. This idea you "thought about years ago"
is called "nano-replacement" Look it up.

Obviously, before uploading can be achieved, we have to understand all the
functioning of neurons that contribute to consciousness and then be able
ot duplicate those functions on another platform.
 
> I never understood that uploading approach. Consciousness-vehicle? What
> is that? A machine with your thoughts? It would take a long time to
> change our organic neurons to metal ones

How long exactly? Are you in a rush? ;)

Do you think it would take a long time, even with nanotechnology-
assemblers and the like?

>and even these would still be
> neurons.

Perfect. I kinda like neurons. Maybe I'll even keep some organic ones
for sentimental value.

>And, like I mention before, it would have to be a continuos
> process and not an instant occurrence.

Well, we can't really do anything *instanteously*.(but thats more physics
than biology) But we can theoretically do it fast, and why not, as long as
it's safe?
  
> > Don't you think your brain is a bit too fragile? Personally, I lose
> > neurons everyday, and they don't grow back. Don't yours do the same?
> > Aren't you going to run out eventually?
>
> Yes, that's called aging. I intend, in the course of my life, to find a
> solution to that problem. I could give a thousand good ideas but that
> would be terribly boring for you.

What about when I bang my head on the door, is that aging? I would say
no, yet my neurons die, never to grow back.

Even in birds, where the neurons do grow back, the information contained
within those neurons is lost forever.

Hey, if you have "good ideas" to stop aging, I'll be very receptive to
them.

> > > As for evidence, well it's more of a philosophical, theoretical problem
> > > rather than a biological one. See the few cases I placed in my last two
> > > messages and you'll know what I mean. Personally, I believe (and notice
> > > the verb to believe instead of the usual verb to think) that I'm my
> > > brain and that is my conscience.
> >
> > I cannot debate against someone who "believes." Have you read Max More's
> > paper on Pancritical Rationalism. I see it as a fairly good alternative
> > to "believing." Can't you see that belief stagnates progress?
> > What if you're wrong?
>
> No-one is perfect, we all make mistakes. With the evidences and proofs I
> have, which are none, I believe my brain is my only conscience. When I
> have some reliable information saying the contrary, I'll change my
> opinion.

If you have no evidence or proofs, what is the source of this "belief" of
yours. Also, what purpose does this belief serve? Are you afraid of
being "undecided"?

What makes you think the brain is the only platform for consciouness? It
sounds like a very religious and anthropocentric assumption.
 
> Nice talking to you,

A pleasure.

geoff.



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