mikedarwin

Actually, cryogenic vessels do not really fail, in the sense I think you mean, over time - with the notable exception of liquid helium and liquid hydrogen storage vessels. Liquid helium has bizzare effects of metal (in addition to quantum tunneling) causing high strength steel to embrittle over time. It is thoought that this occurs due to the presence of helium in solid solution in the metal subjected to loading, and being present at a temperature sufficiently low to form grain boundary cracks as a result of sliding along grain boundaries (which contain steps developed as a result of prior intragranular shear).

Hydrogen "embrittlement" is due to migration of lone hydrogen atoms... (read 398 more words →)

Most of my childhood notes and cryo-memrobilia were lost when my house burned down in September, of last year. So, regrettably, I can't consult my notes from those experiments. However, as best I recall, the mortality rate in yeast frozen in distilled water was ~90%. No special treatment was required beyond removing them from the incubating medium and resuspending them in distilled water prior to freezing. Viability was determined indirectly by adding the frozen-thawed yeast in water to culture medium in an Erlenmeyer flask connected to a water displacement set-up very much like this:

http://herbarium.usu.edu/fungi/funfacts/respiration.jpg

I later repeated this experiment with red cells (my own) which is much more sensitive and directly quantative... (read 511 more words →)

My pleasure!

I have a few (hopefully helpful) comments to add. I am a huge advocate of trying things yourself on a do-able scale. For instance, many years ago I had pretty much the same idea you did and I decided to it out, directly. I lived across the street from a mechanical engineer from Eli Lilly, Inc., named Bud Riever. I asked Bud to figure how much prsssure would be developed if I simply cooled a closed steel container which was completely filled with water to well below the frrezing point? The answer was about 2,000 atmospheres, or about 24,000 psi. As it turns out, a piece of steel pipe of... (read 617 more words →)

I'd say FUNDAMENTALS OF CRYOBIOLOGY, followed by Baust's ADVANCES in BIOPRESERVATION. However, you may find another starting point better. I recently felt the need (out of self defense) to learn about dentistry. That's a bit like saying I decided to learn about neurosurgery:that covers a lot of ground. However, mostly what I was interested in was plain old restorative dentistry and the much more exotic implant dentistry. There are easily half a dosen textbooks on basic, restorative dentistry... After perusing a number, I settled on one as a proper "read through" introduction. All were adequate, but only that one really communicated in my style. The good thing about most modern textbooks is... (read more)

I was asked by several people to comment on this post/proposal. Clearly, Maxikov put a lot of time and effort into this post and, at least in part, there's the pity. When you find you have an idea which seems at once compelling and obvious (in tems of the science) in an already well explored field, the odds are very good that you weren't the first to reach that conjecture. And that almost always means that there is someting wrong with your premises. Very smart and capable people have been trying to achieve cryopreservation of cells, tissues, organs and organisms for over 50 years now and the physical chemistry of water under... (read 742 more words →)

Next up for discussions is the issue of "hyperonconicity." Just as cells require a certain "tonicity" (electrolyte concentration) to maintain their normal volume, tissues with capillaries require a certain concentration (and type) of large (macro-) molecules (colloid) to avoid accumulating water between the cells and becoming swollen, or edematous. Hyperonconicity refers to any solution that has more ability to hold water in the circulatory system (circulating blood or perfusate) than would be the case under NORMAL conditions. The key word there is NORMAL. The macromolecules that comprise colloids can be thought of as molecular sponges that hold water in the capillaries and prevent it from accumulating in between cells as a... (read 631 more words →)

As you can see from the CI data above and below, patient temperatures never come anywhere near -7 degrees, let alone the -20 degrees C called out in either the original animal research, or in CI's own publicly posted protocol for how cryoprotective perfusion is to be administered. In fact, it is necessary to look a number of case reports to even document that CI is perfusing its p atients with VM-1 chilled in a mechanical freezer: "Perfusion with CI−VM−1 vitrification solution began at 3:04 A.M. The CI−VM−1 was at freezer temperature (about −20ºC) in contrast to the ethylene glycol, which was at refrigerator temperature (about 3ºC)" see: http://www.cryonics.org/reports/CI110.html In fact, this patient... (read more)

This Mickey Mouse operation results in perfusate that is at some (variable) subzero temperature when it is pumped through the perfusion circuit and delivered to the patient. While CI case reports are chaotic and inconsistent - some report temperature data during perfusion (http://www.cryonics.org/reports/CI97.html), some do not (http://www.cryonics.org/reports/CI75.html) - it is clear that even with the practice of pre-cooling the VM-1 perfusate in a freezer before perfusing it, CI patients never (so far as I can determine from published case reports, see: http://www.cryonics.org/refs.html#cases) reached subzero temperatures of -7 degrees C throughout VM-1 administration and in fact rarely reach subzero temperatures at all. This despite what CI says in its own description of... (read 374 more words →)

This is a remarkable statement from Ben Best, and one that perhaps speaks best as to why CI is not a cryonics organization being run on a rational, scientific,or evidence based basis. When Ben Best writes: "There is no incompatibility between DMSO and PEG. The PEG make the solution hyperoncotic as the expected. My big mistake, and it was a bad one, I acknowledge, is that most of the vitrification solution was ruined because I was not aware that PEG would come out of solution when placed in a freezer," he is making a statement that has the following outright errors, misunderstandings or distortions in it:

First, DMSO and PEG are incompatible... (read more)

Brian, when you say: "Mike, let's be fair about this. Veterinary surgeons for thoracic surgery (after loss of Jerry Leaf) and chemists for running perfusion machines were also used during your tenure managing biomedical affairs at Alcor two decades ago. You trained and utilized lay people to do all kinds procedures that would ordinarily be done by medical or paramedical professionals, including establishing airways, mechanical circulation, and I.V. administration of fluids and medications. Manuals provided to lay students even included directions for doing femoral cutdown surgery," you are either not reading what I wrote or are not being fair yourself. I not only acknowledge that this was so, I go so... (read 1105 more words →)