X-Message-Number: 7830
Date: 10 Mar 97 18:26:01 EST
From: Michael Darwin <>
Subject: I look forward to seeing Brians work published in full detail.

Chris Benatar writes:

>I look forward to seeing Brians work published in full detail. I find it
>odd that Mrs Visser was bombarded with demands for publication but Brian
>has not even recieved a single request. Can anyone name the exact
>fluorocarbon used for instance. I guess you have got to belong to "the
>fold"

I find the last statement in Chris' post "a little odd."  Maybe the reasons
there has been no salvo of requests for demands of publication of details of FC
cooling are because of one or more of the following:

1) The biology, physics and math required to verify the reasonableness of our
claims are available to anyone with a basic understanding of these areas and
access to a copy of the CRC Handbook of Physics and Chemistry and a pocket
caculator.  (Since I do _not_ have a rigorous understanding of either of either
math or physics myself, I can sympathize if Chris may not have been able to
"check it for himself" and will expand on this a little later in this post).

2) A tremendous amount of technical detail relating to FC cooling has already
been disclosed right here on Cryonet; this is in sharp contrast to the way
Visser handled her work.  

3) We have not gone to the media, the government, or even to the cryonics
community and pleaded, cajoled, or even asked for funding to support our
"breakthrough."

4) We have not gone to anyone and announced that we will soon be reversibly
cryopreserving organs, rats or people "within a few years."  We have made very
clear that there are major problems associated with FC cooling.

5) The (then) President of Alcor and a number of other Alcor and CI people
(including Directors from both organizations) have toured the 21CM facility and

are aware of the basics of the work.  Other key people in the cryonics community
are also aware of the work in some detail.  Some of these people (like Thomas
Donaldson) have asked questions all of which have, I believe, been answered.


Publication of all the technical details relating 21CM's specific techniques for
using FC cooling will await patents and much additional work.  This may sound
like Visser's statement, but, really, it isn't.  If I could easily display
visual data via the Internet I'd publish copies of cooling and rewarming curves
for control and experimental dogs right now.  In fact, if you would _really_

like it, I can give you the tabular data and you can enter it into Excel or some
other graphing program and see for yourself how fast 20+ kg dogs have been
cooled and rewarmed from -85 C.

The basic feasability of perfusing entire mammals with FC has been established
in the literature in the following paper:


Sims DE, et al, Non aqueous fixative preserves macromolecules on the endothelial
cell surface: an in situ study.  European J of Morph. 32(1):59-64;1994.


21CM has no connection with Sims, et al. and we have never spoken to or met with
any of the authors of this paper.  In this paper they document perflurochemical
(PFC) perfusion of rats with osmium laden PFC to obtain detailed information
about the biophysics of the macromolecules which cover the endothelial cells
that line the capillaries (and which have unique and intensely interesting
properties that inhibit blood clotting and stop white cells fron sticking and
"activating").


A paper documenting the biological inertness of the FCs as a class is:

Sparrow JR, et al.   Fibroblast behavior at aqueous interfaces with
perflurocarbon, silicone and flurosilicone liquids.  Invest Opthamol Vis Sci.
31(4):638-646;1990.

As with Sims, et al., we have no connection with Sparrow, et al.  Additionally,
a search of the literature using the key word "perflubron" will yeild a number
of papers documenting the safety and efficacy of perflubron and related FCs on

prolonged contact with the lung and other tissues (including extended studies of
cells in culture exposed to perflubron and other FCs).

As to Chris' remark that one has "got to belong to "the fold" to get acess to
which FC 21CM is using, this is an inappropriate and potentially ad hominem
remark.  So far, no one has _asked_ which FC's we're using.  The answer is that
we have used a variety of the straight chain perfluroalkanes in our work.  In
order to get even distribution of FC you need to sequence the introduction of

the compounds; this _is_ proprietary.  As I have generated intellectual property
in the past which has enriched others with millions, my reluctance (and that of
most of the 21CM stockholders) to make a public disclosure of the details of
this work is understandable.

However, to establish the validity of the _claims_ we have made regarding
cooling rates achieveable, all you need to do is pick an FC you can afford to
buy (;-) with a pour point you like, and perfuse an animal with it usig a

circuit containing a pump and a heat exchanger capable of moving the heat at the
rate you desire.

I have no formal advanced education and am very weak in math and physics by any
reasonable academic criteria. However, I do have a good feel for whart is
"practical" and pretty good engineering problem solving abilities.  These alone
are not terribly useful.  Thus, you will find that I have consistently
surrounded myself with math and physics people over virtually my entire
adult-life-career in cryonics.  I took a hard (and deserved) drubbing from Art

Quife in my youth which taught me the value of and the _need_ for this approach.
Thus, you will find that the people I have worked with have included Hugh Hixon

(a biochemist with a pretty good understanding of physics and good math skills),

Paul Waker (a computer professional with a degree(s) in math and physics), Steve

Harris (an M.D. with an extraordinary understanding of physics and math!),  Mark
Connaughton (who has a degree in Engineering Physics) and Brian Wowk (who is
completing his graduate work in Medical Physics).  

These people have done a lot of the hard work of crunching the numbers to prove
or disprove the workability of my various ideas.  In Brian's case, he has added

materially to the solution of the very challenging technical problems associated
with uniform introduction and removal of FCs from the mammalian circulatory
system.

As the to final FC we use, I can tell you that is has a very low pour point,
that its viscosity is about that of blood at -100 degrees C, and that it is
toxicologically benign; i.e., not poisonous to cells.

Anybody who wants to know more can sign a nondisclosure agreement and tour the
21CM lab.  Otherwise, do what I did: get thee to a good set of textbooks,
appropriate experts, and learn how to use a good pocket calculator; I'm sure
that's what other math and physics types on this list have already done!

Mike Darwin  


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