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Vitrification references edit
I removed the unsourced mention of vitrification because CAS freezers do not use vitrification, nor can CAS technology result in vitrification without much lower temperatures and higher cryoprotectant concentrations. Cryobiologist (talk) 22:23, 5 December 2012 (UTC)
- (A) According to the glass transition article, the temperature of vitrification is always below the melting point, so how is it possible for anything which is vitrified to not also be technically frozen?
- (B) In light of this video of supercooling water in a CAS freezer, is there any reason to believe that vitrification in CAS freezers would require chemical cyroprotectants? 2010 SO16 (talk) 18:10, 11 December 2012 (UTC)
- (A) The process of vitrification *necessarily* prevents freezing from occurring by altering viscosity and avoiding transition to crystalline state equilibrium; frozen = crystalline solid, vitrified = highly viscous quasi-liquid. Re-read glass transition, vitrification, and Cryopreservation#Vitrification carefully.
- (B) You don't need chemical cryoprotectants to supercool water. [1] This is not vitrification and has nothing whatsoever to do with vitrification, and AFAIK, the CAS system does not vitrify anything. Blacksun1942 (talk) 19:47, 31 January 2014 (UTC)
- @Blacksun1942: how do you feel about the additional references below? By "nothing whatsoever" do you mean that a system which can supercool water reliably isn't more likely to vitrify tissue while freezing it? Also, do you have a reference stating that non-polar molecules frozen without crystals are a "highly viscous quasi-liquid" instead of frozen? 114.94.27.250 (talk) 21:09, 13 February 2014 (UTC)
- If you'd read the wikipedia articles mentioned above, you would not have asked me the last question. I will assume that I am talking to James, yes? To say that something is being "vitrified" during "freezing" is to misapply the terminology, though people might assume that by "freezing," you mean simply "lowering the temperature," is that correct? Of course supercooling can *lead* to the vitrification of water, but again, supercooling *per se* is not vitrification; The distinction matters because the above video unambiguously shows the crystallization of supercooled water; it does not depict water in the non-frozen, vitrified glass state (which is all vitrification is). Supercooling (and vitrifying) purified water is easy enough provided you can get down to the glass transition temperature; Supercooling and vitrifying anything as complex as tissue without the use of special vitrification solutions is a different story entirely. I would like to know how exactly you propose to prevent heterogeneous ice nucleation and crystal growth in tissue without the cryoprotectants needed to prevent ice formation in the first place, and thus facilitate vitrification? Vitrification of tissue has never been achieved without vitrification solutions. I'll gladly engage you fully on this (as my time permits), and share copious published literature, but first tell me, have you thoroughly read the above-mentioned wikipedia articles on these topics? Blacksun1942 (talk) 14:21, 14 February 2014 (UTC)
- Yes, but not the most recent versions. Imagine you are trying to explain a microwave oven to someone from 1850, but they kept telling you internal basting with a special marinade was the answer. How would you feel if they were unable to provide you with sources saying that the marinade outperformed your microwave? 114.94.27.250 (talk) 22:26, 14 February 2014 (UTC)
- If you'd read the wikipedia articles mentioned above, you would not have asked me the last question. I will assume that I am talking to James, yes? To say that something is being "vitrified" during "freezing" is to misapply the terminology, though people might assume that by "freezing," you mean simply "lowering the temperature," is that correct? Of course supercooling can *lead* to the vitrification of water, but again, supercooling *per se* is not vitrification; The distinction matters because the above video unambiguously shows the crystallization of supercooled water; it does not depict water in the non-frozen, vitrified glass state (which is all vitrification is). Supercooling (and vitrifying) purified water is easy enough provided you can get down to the glass transition temperature; Supercooling and vitrifying anything as complex as tissue without the use of special vitrification solutions is a different story entirely. I would like to know how exactly you propose to prevent heterogeneous ice nucleation and crystal growth in tissue without the cryoprotectants needed to prevent ice formation in the first place, and thus facilitate vitrification? Vitrification of tissue has never been achieved without vitrification solutions. I'll gladly engage you fully on this (as my time permits), and share copious published literature, but first tell me, have you thoroughly read the above-mentioned wikipedia articles on these topics? Blacksun1942 (talk) 14:21, 14 February 2014 (UTC)
- @Blacksun1942: how do you feel about the additional references below? By "nothing whatsoever" do you mean that a system which can supercool water reliably isn't more likely to vitrify tissue while freezing it? Also, do you have a reference stating that non-polar molecules frozen without crystals are a "highly viscous quasi-liquid" instead of frozen? 114.94.27.250 (talk) 21:09, 13 February 2014 (UTC)
@Jordansparks: re [2] How can a system proven in organ preservation for transplant be unrelated to cryonics? Isn't there a first principles argument saying otherwise? 180.158.74.23 (talk) 11:27, 2 January 2014 (UTC)
I'm not a cryobiologist and I don't have access to the full text of the articles in question. I removed the links because they seemed to have been added by an overzealous layperson who had an even poorer understanding of the science than me. I only see about 3 papers involving teeth. I see a properly skeptical article by Wowk. At best the 3 papers hint that CAS might someday have potential in cryonics. There is no citation available connecting cryonics and CAS, so I can't see how it could meet the Wikipedia criteria --JordanSparks (talk) 16:21, 18 January 2014 (UTC)
- @Jordansparks: how do you feel about:
- http://www.sciencedirect.com/science/article/pii/S0011224013001995
- http://journals.lww.com/transplantjournal/Abstract/2012/09150/Subzero_24_hr_Nonfreezing_Rat_Heart_Preservation__.8.aspx
- http://authors.library.caltech.edu/43141/1/Kobayashi_Cryobiol_2013.pdf and
- http://www.ingentaconnect.com/content/cryo/cryo/2013/00000034/00000001/art00002 ? 114.94.27.250 (talk) 21:07, 13 February 2014 (UTC)
- But can you articulate the direct, immediate relevance to cryonics? For example, vitrification and the improvement of vitrification formulas and protocols have direct relevance to cryonics because this is currently the optimal protocol by which individuals are cryopreserved. Oscillating magnetic fields may play some role in some yet-to-be-conceived cryonics protocol, but I fail to see the direct link to the patented CAS freezers. Blacksun1942 (talk) 23:58, 13 February 2014 (UTC)
- Are there other sorts of freezers which have had greater success rates in organ preservation or supercooling water? Have any cryopotectants ever had greater success? There will always be a direct immediate cause-and-effect relationship from organ preservation of previously difficult organs and cryonics, right? 117.136.8.98 (talk) 07:23, 14 February 2014 (UTC)
- Of course there has been greater success in tissue preservation than that achieved by CAS; you'd know this if you'd read the wikipedia articles mentioned on this page. Here are a few pop-media articles The-Scientist- Icing Organs, New Scientist - Heart of Glass (relevant papers available on request). There isn't *necessarily* always a direct (and especially not immediate) cause-and-effect relationship between organ preservation and cryonics; the practice has its own unique set of concerns (e.g. regarding global cerebral ischemia) and has a messy history full of competing priorities and personalities. The paper by Kobayashi and Kirschvink is very interesting. Unfortunately, there are also papers like this one involving "supercooling facilitated by a variable magnetic field": http://www.nature.com/protocolexchange/protocols/2440 (read the editorial notes at the bottom of the page) http://www.nature.com/srep/2012/121108/srep00840/full/srep00840.html Blacksun1942 (talk) 14:41, 14 February 2014 (UTC)
- PMID 16297800 is for only 21 hours and your reference says "more antifreeze can be toxic". Is there really a group of people who take money from the elderly and infirm to tell them that they will be preserved with antifreeze? Isn't that barbaric? The references in support of CAS freezers involve 24 hours to several days experiments, with evidence that it lasts much longer. I agree that the field is filled with insufficiently mature science, for example using "magnetic fields" as a principal attribute of CAS freezers instead of the electromagnetic spectrum of the resonance frequencies of the H-O bonds of water in attenuating tissue. I expect those terminological differences to be resolved as soon as the science press figures out what a quantum breakthrough these freezers represent. If you have any evidence that preventing ice crystal nucleation by freezing tissue before freezing water (and e.g. reversing the process upon thawing) is not both freezing the entire tissue and vitrification in the physical sense, I would like to see it. 114.94.27.250 (talk) 22:45, 14 February 2014 (UTC)
- When non-profit organizations do to their brains something similar to what was done to this kidney in the belief that a potentially viable brain, like any organ, can in principle be reversibly cryopreserved, that is of course much more barbaric than the for-profit organizations that burn them or bury them after beautifying their embalmed corpses for the benefit of relatives who unwittingly carry on the deeply-ingrained human traditions of senicide because they, like you, harbor hyberbolic distortions about cryonics (if they harbor any sentiment or knowledge about cryonics at all). Your allusion to microwaves above is disingenuous, James...yet I can't figure out what it is about the wikipedia articles (and their references) that leaves you unsatisfied. If you know that there is such a thing as electromagnetic resonance frequencies, then how is it that you don't understand what a phase transition is? Again, freezing, vitrification, glass transition. Once you've read those carefully, you might be ready for a Google search. Please do your homework and keep the hyperbole at the door. Blacksun1942 (talk) 00:09, 15 February 2014 (UTC)
- Why do you think I don't know what a phase transition is? I'd rather have to deal with hyperbolic corrections towards the truth than snake oil, but your point about attempted chemical cryoprotection being less barbaric than unmitigated death is well taken. 114.94.27.250 (talk) 01:09, 15 February 2014 (UTC)
- When non-profit organizations do to their brains something similar to what was done to this kidney in the belief that a potentially viable brain, like any organ, can in principle be reversibly cryopreserved, that is of course much more barbaric than the for-profit organizations that burn them or bury them after beautifying their embalmed corpses for the benefit of relatives who unwittingly carry on the deeply-ingrained human traditions of senicide because they, like you, harbor hyberbolic distortions about cryonics (if they harbor any sentiment or knowledge about cryonics at all). Your allusion to microwaves above is disingenuous, James...yet I can't figure out what it is about the wikipedia articles (and their references) that leaves you unsatisfied. If you know that there is such a thing as electromagnetic resonance frequencies, then how is it that you don't understand what a phase transition is? Again, freezing, vitrification, glass transition. Once you've read those carefully, you might be ready for a Google search. Please do your homework and keep the hyperbole at the door. Blacksun1942 (talk) 00:09, 15 February 2014 (UTC)
- PMID 16297800 is for only 21 hours and your reference says "more antifreeze can be toxic". Is there really a group of people who take money from the elderly and infirm to tell them that they will be preserved with antifreeze? Isn't that barbaric? The references in support of CAS freezers involve 24 hours to several days experiments, with evidence that it lasts much longer. I agree that the field is filled with insufficiently mature science, for example using "magnetic fields" as a principal attribute of CAS freezers instead of the electromagnetic spectrum of the resonance frequencies of the H-O bonds of water in attenuating tissue. I expect those terminological differences to be resolved as soon as the science press figures out what a quantum breakthrough these freezers represent. If you have any evidence that preventing ice crystal nucleation by freezing tissue before freezing water (and e.g. reversing the process upon thawing) is not both freezing the entire tissue and vitrification in the physical sense, I would like to see it. 114.94.27.250 (talk) 22:45, 14 February 2014 (UTC)
- Of course there has been greater success in tissue preservation than that achieved by CAS; you'd know this if you'd read the wikipedia articles mentioned on this page. Here are a few pop-media articles The-Scientist- Icing Organs, New Scientist - Heart of Glass (relevant papers available on request). There isn't *necessarily* always a direct (and especially not immediate) cause-and-effect relationship between organ preservation and cryonics; the practice has its own unique set of concerns (e.g. regarding global cerebral ischemia) and has a messy history full of competing priorities and personalities. The paper by Kobayashi and Kirschvink is very interesting. Unfortunately, there are also papers like this one involving "supercooling facilitated by a variable magnetic field": http://www.nature.com/protocolexchange/protocols/2440 (read the editorial notes at the bottom of the page) http://www.nature.com/srep/2012/121108/srep00840/full/srep00840.html Blacksun1942 (talk) 14:41, 14 February 2014 (UTC)
- Are there other sorts of freezers which have had greater success rates in organ preservation or supercooling water? Have any cryopotectants ever had greater success? There will always be a direct immediate cause-and-effect relationship from organ preservation of previously difficult organs and cryonics, right? 117.136.8.98 (talk) 07:23, 14 February 2014 (UTC)
- But can you articulate the direct, immediate relevance to cryonics? For example, vitrification and the improvement of vitrification formulas and protocols have direct relevance to cryonics because this is currently the optimal protocol by which individuals are cryopreserved. Oscillating magnetic fields may play some role in some yet-to-be-conceived cryonics protocol, but I fail to see the direct link to the patented CAS freezers. Blacksun1942 (talk) 23:58, 13 February 2014 (UTC)
Mechanism of action; "sympathetic resonance" edit
CAS may work by sympathetic resonance, but if this is not explicitly stated in a reference, than it is WP:OR. For example, the referenced exchange between Wowk and the authors of the original paper makes it clear that, at least from Wowk's perspective, the mechanism by which CAS reduces freezing damage had yet to be elucidated; the study authors attempt to correct this, and a paper previously linked to above ( http://authors.library.caltech.edu/43141/1/Kobayashi_Cryobiol_2013.pdf ) offers more insight into how CAS might actually work given that, according to Kobayashi and Kirschvink, "Papers and patents published by the ABI group postulate mechanisms of action that do not agree with basic bio-physics." Nevertheless, the term sympathetic resonance or the word resonance appears in none of these papers. If this term cannot be established in any reference, then it is WP:OR/WP:SYNTH and must be removed. Blacksun1942 (talk) 14:19, 15 February 2014 (UTC)
Secondary sources edit
This articles sounds a little promotionally and is lacking secondary sources. Doc James (talk · contribs · email) (if I write on your page reply on mine) 22:13, 15 February 2014 (UTC)
Recent publications edit
Is [3] a reasonable secondary news source for this Nature article? Shouldn't we have a discussion of this Transplantation Analysis and Commentary article phrased as commentary? (E.g. "Cardiologists writing in the journal Transplantation say that the technology is promising and deserves further clinical evaluation" or some such?) 67.215.13.242 (talk) 00:23, 3 July 2014 (UTC)
New reviews edit
http://www.tandfonline.com/doi/abs/10.1080/10408398.2015.1004569