X-Message-Number: 4763 Date: Fri, 11 Aug 1995 04:56:34 -0700 (PDT) From: Doug Skrecky <> Subject: reply to messages #4730,4732 & 4742 In message #4730 Yvan Bozzonetti suggested that chemical means of preservation might be a cost effective alternative to cryonics for uploading. However I would like to urge a caution about advocating the use of thyme extract as a preservative. There exists a large amount of information on the effects of established or proven chemical fixatives. Before thyme extract could be used with equal confidence it would have to accumulate a comparible database. This would cost a lot of money, thus negating one of the main advantages of chemical preservation. In message #4732 Eugen Leitl typed "Glycerol functions as a cryoprotectant, as a super-cooling agent, and has been shown to aid in desiccation resistance in cysts of Artemia (Clegg, 1962)". I would like to mention that up-to-date research on anhydrobiosis indicates that it is nonreducing sugars such as trehalose or sucrose that confer desiccation resistance, not glycerol. (Annu. Rev. Physiol. 54:579-599 1992) In message #4742 Joseph Strout suggested that the combination of fixation and freezing could reduce the risk of rotting when the LN2 supply runs out. I would like to mention in this regard that alcohol is both an effective fixative as well as a cryoprotectant. Replacing glycerol with alcohol would certainly increase the reliability of cryonics over the long term. However replacing glycerol with sucrose might be an even better substitution since then freeze drying would become a possibility. EOF Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=4763