X-Message-Number: 14955 Date: Sun, 19 Nov 2000 13:12:19 -0500 From: Kitty Antonik <> Subject: Re. #14938 and #14951 [Ettinger on Vitrification Viability] I have not read Fred Chamberlain's statements on Alcor's website re. Vitrification, so am only addressing Bob Ettinger's statements in both of the above posts in regard to The Institute for Neural Cryobiology's (INC's) Hippocampal Slice Project (HCSP) that are incorrect and or misleading. " The evidence Fred cites relates to experiments at higher temperatures or/and specimens other than mammalian brains, except for the INC rat brain slices showing 53% "viability" (by an unidentified criterion). Also, of course, that evidence relates to ideal laboratory conditions, not actual prevailing conditions for cryonics patients." [#14951] "d) Fred says the INC hippocampal research showed 53% "viability" after vitrification and rewarming. Viability by what criterion?... " [14938] The viability testing method was fully specified at the Asilomar Conference in the presentation by the scientist in charge of the experiment who is also the Science Director of INC. That same information was provided in post #14049: Perfected Brain Slice Cryopreservation now in Sight [Paul Wakfer] with the specific paragraph copied here: "2. Using a potassium/sodium ratio assay for cellular viability (cells need to actively maintain this ratio in order to stay alive), addition & removal of the VS currently used in the HSCP yields viabilities in the range of about 50% of the viability of fresh, untreated control slices. Slices vitrified in this VS have shown no injury attributable to vitrification & warming per se in two separate experiments, and the reproducible cellular viability of such vitrified hippocampal slices is now at 53% of untreated controls. The primary challenge, then, is to reduce injury associated with the VS itself." In regard to some confusing remarks in the subject posts re. temperature for vitrification, I will say only that again at Asilomar the chief scientist for the HCSP stated that the lower temperature of LN was not a requirement. (Also, that warming from the higher temperature was less prone to damage during that process than from the LN temperature of -196C.) This of course would present the "challenge" for providing the -130C preservation temperature to the cryonics storage facilities. Stephan Valentine the architect for "The Time Ship" who also presented at the Asilomar Conference addressed in general terms how this could be done using LN. Other methods I'm sure have been and will be explored. In addition, it apparently must be repeated again, that the research performed by INC is pure cryobiology *science* following all the rules of the scientific method. It's experiments are not specifically performed to find a better method for human cryopreservation and its published results will be usable by all those in the field of cryobiology. The results of INC's work will in all likelihood be highly usable by cryonics organizations but first and foremost, these results must meet the test of being reportable for peer review and being repeatable by others in the field of cryobiology. Lastly, Paul Wakfer posted the following to sci.cryonics in response to a post 11/18/00 Zeb Haradon wrote: > > "Bryan Hall" <> wrote in message > news: > > http://www.alcor.org/eventsb.html#Update > > I got a notice in the mail from them regarding this, it's great news. It > basically says they are now going to be vitrifying neuro-suspendees. > Since vitrification will not cause any freezing damage, and the only issue > is the toxicity of the vitrification chemicals, this means that > nanotechnology will (probably) not be required for revival. I hope this > means research will begin soon on realistic revival scenerios. I think that your statements go too far in their interpretation of the benefits of vitrification. First, being able to vitrify by cooling does not necessarily mean that specimens can remain ice-free or otherwise damage free during rewarming. Second, we have always been able to vitrify, but this was not done because the toxicities involved (even some disintegration of cell membranes) were clearly not tolerable to restoring life. The current vitrification procedure does still not leave the tissue viable, but the toxicity is low enough that a decision has been made by someone (perhaps partly for promotional reasons) that toxicity damage is "better" than ice damage. Since we currently have no method of restoring from either kind of damage, this decision is at best a "guesstimate" rather than a decision based on scientific research. To take an extreme example, long-term preservation in embalming fluid has always been possible (and without ice damage!), but no one ever proposed it because no one ever thought that life could ever be restored from that state, or even that the mind was fully captured and preserved. Thus, until we actually finish the necessary research to restore to life a person who is preserved in a manner which allows no deterioration over a long term, I think that it is premature to say what kind of technology will or will not be necessary for that restoration. -- Paul -- The Institute for Neural Cryobiology - http://neurocryo.org A California charitable corporation funding research to perfect cryopreservation of central nervous system tissue for neuroscience research & medical repair of the brain. Voice-mail: 416-968-6291 Fax: 559-663-5511 More Life for Us All, Kitty Antonik Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=14955