X-Message-Number: 9469
Date: Sun, 12 Apr 1998 18:25:26 -0400 (EDT)
From: Charles Platt <>
Subject: More basics

Ettinger () wrote:
> not. (This was a gross libel of the Ukrainians, since it implied first that

> their report materially misrepresented the facts, and second that they had not
> honored their assignment, which was precisely to follow the CI procedure as
> closely as possible.)

Calm down, Bob. You're becoming somewhat shrill.
The quotes I presented from Pichugin showed that 

a) When Pichugin tried CI's style of single-pass perfusion, it created
osmotic damage; and

b) subsequently he modified the technique to use incremental increases in
concentration, in accordance with standard cryobiological procedure.

Until now, you denied that there was any difference between Pichugin's
studies and CI's protocol. Apparently you were wrong: in at least one
series of experiments, Pichugin tried to improve on your protocol because
the damage it inflicted was unacceptable. 

Therefore, I stand by my original statement: it was misleading to suggest
that CI's one-pass full-concentration technique was "validated" by
Pichugin. 

Since your own cryobiologist (along with everyone else in the field)
evidently understands that ramped concentrations are safer than one-pass
perfusion, will you agree that there might be some truth in this after
all? 

Slow freezing causes avoidable damage. One-step open-circuit perfusion
with high concentration of glycerol causes avoidable damage. I have made
these points 5 times, now. 

If the damage is avoidable, why not avoid it? 

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