X-Message-Number: 6716 From: Brian Wowk <> Date: Thu, 8 Aug 1996 14:01:54 -0500 Subject: SCI.CRYONICS objectivity Bob Ettinger writes: > 2. Brian apparently roughed up Mrs. Visser through misguided > loyalty to someone else, allowing his objectivity to lapse. My most harsh remarks, which Mrs. Visser took greatest exception to, were in response to claims that she had revived *entire rats* from liquid nitrogen. This was subsequently revealed to be an error in correspondence between Mrs. Visser and Anatole Dolinoff. I have clarified this with Mrs. Visser privately, and much of this misunderstanding has been cleared up. >Brian says he didn't realize it might be applicable to larger >organs, because he thought it required flash freezing. But he >knows, first, that you can't "flash" freeze anything as large as a >rat heart; and second, even if fast freezing was involved, he had >no way of concluding that ONLY fast freezing would work. Perhaps the best frozen brain histology in the world today is obtained not by cryonics organizations, but by neurological research banks that slice brains into 5mm slices and freeze the slices between metal plates at -196'C without any cryoprotectant at all. The faster the freezing, the smaller the ice crystals, and direct immersion of small tissue samples into liquid nitrogen can result in ice crystals so small that the tissue is almost vitrified. Direct immersion of tissue into liquid nitrogen is a completely different cryobiological regime than the slow cooling large organs like the human brain require. I look forward to confirmation that the South African cryoprotectant is effective at cooling rates compatible with brain preservation. > The whole (Prometheus) project may even be outdated by other > developments. We'll just have to see. Given that the goal of the Project is to convincingly demonstrate complete neurological recovery after deep cooling of a brain, who is going to do that before 1998? Even if methods are developed, proven and published for cryopreserving every transplantable organ in the human body within the next 18 months, who but the Prometheus Project will do the neuroscience experiments necessary to validate the methods on the brain? This Project is crucial to cryonicists not because organ cryopreservation breakthroughs might not be forthcoming within the next 18 months, but *especially because* organ cryopreservation breakthroughs will be published within the next 18 months. *************************************************************************** Brian Wowk CryoCare Foundation 1-800-TOP-CARE President Human Cryopreservation Services http://www.cryocare.org/cryocare/ Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=6716