Depressed Metabolism

Mind uploading advocate Kenneth Hayworth has launched an interesting website devoted to the science of brain preservation. Of particular interest is his Proposal for a Brain Preservation Technology Prize (PDF). This document includes one of the most comprehensive discussions of chemopreservation as a strategy for personal survival. For example, one of the most common objections [...]

There is a growing literature that discusses the technical aspects of revival of cryonics patients. The following list of the published literature was compiled by Ralph Merkle and Robert Freitas and published as an appendix of their article on molecular nanotechnology in Cryonics Magazine 2008-4:
Robert C.W. Ettinger, The Prospect of Immortality, Doubleday, NY, 1964
Jerome B. [...]

This is the eighth entry in a series about resuscitation of non-hibernating rodents from circulatory arrest at ultraprofound hypothermic and high subzero temperatures. In 1982, P.D. Rogers and G.P. Webb published some of their observations (based on previous papers and a Ph.D thesis) after carrying out a classroom demonstration of suspended animation in which they [...]

Robert J. White is most known, or perhaps most notorious, for his work on primate head transplants. Less known, but more relevant to the practice of human cryopreservation, is his work in cerebral ischemia, hypothermia, and brain preservation. Most of White’s innovative work was published in the 1960s and 1970s. White also published a substantial [...]

It has been shown that perfusability of the brain is significantly compromised after long-term (>5 min) ischemic events (the “no reflow” phenomenon). Improving cerebral blood flow after circulatory arrest is one of the fundamental objectives of human cryopreservation stabilization protocol.  To that end, cryonics organizations administer the resuscitation fluid Dextran-40 and the drug Streptokinase to [...]

In 2007, cryobiologist Armand M. Karow passed away. Unlike many contemporary cryobiologists, Karow offered cautious support for the objectives of cryonics. In the mid-1960s, Karow served on the Scientific Advisory Council of the Cryonics Societies of America (CSA). He also published a regular column titled “Scientifically Speaking” in Cryonics Reports, a publication by the Cryonics [...]

In August 2008, Neurobiology of Aging published the interesting observations of den Dunnen, et al. of the post-mortem body of a 115 year old woman, which showed no evidence of atherosclerosis. Her brain was devoid of the amyloid plaques characteristic of Alzheimer’s disease and neural density was on par with healthy persons 60-80 year of [...]

In “The chemistry of neuroprotection”, the author argues convincingly that there could be great benefit from a systematic and rigorously scientific study of the physical chemistry of putative neuroprotectants vis-à-vis their pharmacological effect. However, the first example used of the earliest thinking in this direction (which comes, not surprisingly via V. A. Negovskii, the father [...]

In a review of the 1998 21st Century Medicine seminars, Cryonics Institute president Ben Best writes:
“The presentations impressed upon me how much witchcraft and how little science has gone into the study of cryoprotectant agents (CPAs). This might be understandable in light of the fact that most cryobiologists are, in fact, biologists. I suspect [...]

A recent study in Rejuvenation Research reports that a combination of dietary supplements confer neuroprotection in stroke. Over a 2 week period rats received either a proprietary formulation of blueberry, green tea, Vitamin D3, and carnosine  called NT-020 or vehicle (i.e., the same solution minus the compounds of interest) before stroke was induced through middle [...]

The full text of the Life Extension Foundation magazine article (August 2008) describing the use of Enbrel for the treatment of Alzheimer’s disease and announcing LEF’s new Enbrel trial, is now available. As previously discussed, Enbrel (entanercept) has been shown to provide immediate benefits in Alzheimer’s patients, improving memory performance and less frustration and agitation [...]

More than a decade of basic research and clinical evidence now implicates inflammatory processes in the pathogenesis of Alzheimer’s disease (AD). TNF-alpha is a pro-inflammatory cytokine, also known as the “master regulator” of the immune response, and is the key initiator of immune-related inflammation in the brain. Much evidence has linked excess TNF-alpha to the [...]

The latest issue of Life Extension Magazine (August 2008) contains an encouraging report about off-label use of etanercept (commercial name: Enbrel) to reverse the cognitive deficits associated with Alzheimer’s disease. Etanercept is a tumor necrosis factor (TNF) blocker that is used to treat diseases such as ankylosing spondylitis, juvenile rheumatoid arthritis, psoriasis, psoriatic arthritis, and [...]

Induction of hypothermia can reduce injury to the brain when it is deprived of oxygen. How fast do we need to cool a patient during cardiac arrest or stroke to prevent irreversible injury to the brain?
It is an established fact that induction of hypothermia prior, during, or after circulatory arrest can reduce brain injury. As [...]

As discussed in a previous post, perfusion of the brain following long-term (>5 min) ischemia has been shown to be significantly compromised, particularly in subcortical regions. An interesting recent article by Ristagno, et. al in Resuscitation (May 2008) has added new data to the equation, using some of the most advanced technologies available for measuring [...]

Cryopreservation of the brain depends on the removal of blood from the brain’s vasculature and its replacement with cryoprotective solutions in order to prevent ice crystal formation (freezing) during cooling (i.e., facilitate vitrification). Ultimately, the success of a good cryoprotectant is limited by perfusability of the brain, or the ability of cryoprotective solutions to penetrate [...]

Neuroprotective agents for stroke continue to fail in clinical trials. One important reason is that the therapeutic window for many of those agents is too narrow to confer benefits to acute stroke victims. It would be desirable to have a potent neuroprotectant agent that has a wide therapeutic window, few side effects, and can be [...]

“People like you and I, though mortal of course like everyone else, do not grow old no matter how long we live…[We] never cease to stand like curious children before the great mystery into which we were born.”
Albert Einstein

One sign of the lack of faith in the future progress of technology and the poor acceptance [...]

Because the current generation of vitrification agents permit cryopreservation of the brain without ice formation, the current objective of cryonics research is maintenance of viability of the brain during cryopreservation. The most popular viability assay that has been used in cryonics and cryonics-associated cryobiology research is the potassium/sodium ratio (K+/Na+ ratio). Because the ability [...]

The blog Practical Ethics reports on pioneering research from a group of scientists in Cambridge who are using fMRI scans to study the brains of people who have been diagnosed as being in a vegetative condition. A Persistent Vegetative State (PVS) is a condition that is characterized by a state of wakefulness without [...]

The journal Neuropharmacology recently published a new review of the current state of the art in neuroprotection for ischemic stroke. A strict definition of a neuroprotectant excludes agents that have as their goal circulatory patency or the reversal of vascular occlusion, such as thrombolytics and anticoagulants. As a consequence, the only medication that is approved [...]

One scientific question that weighs heavily on the feasibility of contemporary cryonics is what happens to the brain after cardiac arrest. Common wisdom has it that the brain “dies” within 5-7 minutes after circulatory arrest. This is true in the sense that patients resuscitated from such insults die of brain death (or develop higher brain [...]

In an effort to determine why so many cytoprotective treatments for stroke that are shown to be promising in laboratory animal experiments ultimately fail in human clinical trials, DeBow et al. performed an analysis of cytoprotection studies published in several leading journals. While noting that limitations in preclinical assessments also contribute to the premature advancement [...]

L-Kynurenine (L-KYN) is one of the neuroprotective agents used in cryonics stabilization protocol to limit injury to the brain after cardiac arrest. Administration of L-KYN was perceived to be essential to resuscitate dogs from extended periods (up to 17 minutes) of normothermic ischemia during the Critical Care Research (CCR) cerebral resuscitation experiments in the [...]

Elevation of body temperature occurring as a result of hypothalamic coordination of autonomic, neuroendocrine, and behavioral responses in reaction to physiological injury or invasion is generally known as fever. Traditional thought is that the “febrile response” is beneficial in preventing the proliferation of invading microorganisms, but some caregivers consider fever to be harmful and prescribe [...]

In their paper “The role of leukocytes following cerebral ischemia: pathogenic variable or bystander reaction to emerging infarct?” D.F. Emerich et al. review the literature on the involvement of neutrophils in cerebral ischemia:
“We reasoned that if neutrophils play an important pathogenic (i.e., cause-effect) role in the neuronal damage that follows a stroke, then one should [...]

An ongoing quest in cryonics is the successful demonstration of memory sustainment after cryopreservation of the brain and rewarming from cryogenic temperatures. To that end, landmark experiments were performed by Pichugin, et al. (2006) on rat hippocampal brain slices which indicate that the hippocampus retains excellent structural integrity and viability (as measured by Na+/K+ ion [...]