X-Message-Number: 18690 From: Date: Sun, 3 Mar 2002 10:08:55 EST Subject: Research Each issue of The Immortalist is expected to contain (and the last two do contain) updated summaries of Dr. Yuri Pichugin's CI research and related material. Our web site does also. Today's notes are just a part of recent developments. First, a relatively recent result from France, apparently not widely noted. Charpak and Audinat in Proc. Natl. Acad. Sci. USA April 14, 1998, studied brain tissue from rodents dead of cardiac arrest, and found the tissue could be reactivated after 5-6 hours by supplying glucose and oxygen. "In rat brain slices prepared 1-6 hours after cardiac arrest and maintained in vitro for several hours, cells with normal morphological features, intrinsic membrane properties, and spontaneous synaptic activity were recorded from various brain regions. In addition to functional membrane channels, these neurons expressed mRNA, as revealed by single-cell reverse transcription-PCR, and could synthesize proteins de novo." Leonard et al (Exp Neurol 1991 Sep; 113(3):373-7) had kept a dead rat at room temperature for 30 minutes after death and found viability of neurons in hippocampal slices about 72% of controls, according to a bioelectric criterion. Dr. Pichugin recently followed up the Leonard work by also keeping a rat (which had died under anaesthesia) for 30 minutes without cooling, and obtained 95% viability of hippocampal slices by the K/Na criterion. All these results--along with many others, some from decades back--prove that post mortem brain deterioration is relatively slow and limited, compared to the impression that most laymen, and even most physicians have, viz., that after a few minutes of ischemia there is "irreversible" death. Of course, none of this proves that patients preserved after delays (or without delays, for that matter) will ever be recovered, but it helps the perspective. We must always remember that "partly dead" also means "partly alive," and something that is partly alive may be potentially capable of complete repair with relative ease. Dr. Pichugin has also done some recent work with vitrification, and obtained more than 50% viability, by the K/Na criterion, after perfusing with 70% glycerol and quickly cooling to - 130 C. (This is similar to results reported with the newer 21CM CPAs a year or two back, although not as good as later results Dr. Pichugin obtained with those, which approached 100%.) This does not mean that CI (or anyone else) now can offer vitrification in the sense of demonstrated success and effectiveness with procedures actually being used on human patients, or animals for that matter. The problems of quick cooling and uniform permeation and equilibration are very much more difficult with whole brains than with thin slices, among other things. But we are learning more all the time, and improvements will inevitably follow. Robert Ettinger Cryonics Institute Immortalist Society www.cryonics.org Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=18690