X-Message-Number: 9718 From: Ettinger <> Date: Fri, 15 May 1998 19:08:22 EDT Subject: Pichugin's recent work Dr. Yuri Pichugin in the Ukraine has completed a series of cat head experiments for the Immortalist Society and the Cryonics Institute, with two objectives. One was to test DMF (dimethyl formamide) as a brain cryoprotectant generally, comparing its effectiveness to that of glycerol. The other was to test cracking limits both with glycerol and DMF. The upshot is that, with the concentrations and cooling/warming rates used, DMF results are not as good as glycerol results. As used, DMF is more toxic than glycerol. If concentration is increased from 30% to 40% there is partial precipitation of salts from physiological solutions. Optimum concentrations of DMF are 20%-30%. Cat brains with DMF had microcracks, macrocracks, and ice holes. Dr. Pichugin thinks Mrs. Visser's method is probably only effective for small masses of muscle tissue that can be cooled and warmed rapidly. He thinks it still may be possible to perfect her method even to apply to human hearts, but only as a possibility after a large and expensive effort. The text of Dr. Pichugin's reports will appear before long on our web site. We also expect in a couple of weeks to have the full photo sets from the 1994 work. Robert Ettinger Cryonics Institute Immortalist Society http://www.cryonics.org Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=9718