X-Message-Number: 17172 From: Date: Wed, 1 Aug 2001 12:17:59 EDT Subject: Bozzonetti and repair Yvan Bozzonetti writes in part: >When most nano supporter think about nano repair, I feel they think in fact > about micro surgery done by micrometer sized robots. That technology may >indeed be produced as a spin off from micro electronics device making. It > would be useful in cryonics to repair cracks in frozen bodies for example. >That would be fine, but it fall short of the requested capabilities to get >out of the frost. The main problems are at molecular level, we must reshape >badly folded proteins or membrane molecules. This is a quantum problem, and >to solve it, the nano system must be able to compute all the intermediate >steps between the actual structure and the retrofitted one. >The problem: even the biggest supercomputer today can't solve that problem of >a single molecule. >What about the billions of molecules to repair? What about putting the >computer on a molecular scale system? I am frequently dazzled by Mr. Bozzonetti's apparent brilliance. (I say "apparent" only because I usually don't know enough to decide whether his ideas are sound.) However, in this case I think he is missing crucial points. First, most agree that there is massive redundancy in the brain, which affects the argument in obvious ways. Second, only a small fraction of the molecules in the brain are determinative of uniquely personal information. Third, many think the most important bits of information are encoded in the connections between neurons, which will not necessarily be affected by misfolding of proteins. Fourth, Ralph Merkle and others have quantitatively addressed (at least in a preliminary way) what they consider to be the most important aspects of nano-repair. Fifth--and most importantly--we have a long list of EXPERIMENTAL verification of retention of viability after freezing (or/and vitrification). Yuri Pichugin and colleages, doing contract work for the Cryonics Institute and the Immortalist Society, demonstrated coordinated electrical activity in networks of neurons in pieces of rabbit brains after rewarming from liquid nitrogen temperature, using glycerol as cryoprotective agent. (See our web site.) In the '60s Audrey Smith and colleages showed normal behavior of re-warmed hamsters after about half the water in the brains had changed to ice. Many other experiments--see our site--have demonstrated retention of various aspects of structure or/and function after freezing and rewarming of nervous tissue. In California recently, Pichugin and his employers (including the Institute for Neural Cryobiology) demonstrated up to and including 100% viability (by the K/Na criterion) of rat hippocampal slices rewarmed after presumed vitrification. We don't have to repair all the molecules. We don't even necessarily have to understand the problem in full detail. We can sometimes cure a disease without understanding it, and we can probably repair a brain without fully understanding it. I am not a short-term optimist about fully and immediately reversible cryostasis, but I believe that CI research under Dr. Pichugin, and the work of others, will continue to yield important improvements. I also continue to think that even most of our "bad" cases are not hopeless, and that Mr. Bozzonetti has greatly overstated the difficulties. Robert Ettinger Cryonics Institute Immortalist Society http://www.cryonics.org Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=17172