Navigation Links
Cryostasis (clathrate hydrates)


Cryostasis is the reversible cryopreservation of live biological objects.

Cryostasis is not cryonics. Cryostasis is not hibernation. Unlike cryostasis, cryonics is a practice of cryopreservation of legally dead people and pets.

Cryostasis was a plot in many famous science fiction novels and movies. At present, there is no any effective reversible cryopreservation procedure for live humans and mammals.

The new technology of cryostasis for biological objects using clathrate forming substances under high pressure can be promissing.[1] [2]

Living tissues cooled below the freezing point of water are damaged by the dehydration of the cells as ice is formed between the cells. The mechanism of freezing damage in living biological tissues has been elucidated by Renfret (1968) (Renfret A.P. Cryobiology: some fundamentals in surgical context. In: Cryosurgery. Rand R.W., Rinfret A.P., von Lode H., Eds. Springfield, IL: Charles C. Thomas, 1968) and by Mazur (1984): ice formation begins in the intercellular spaces.[3] The vapor pressure of the ice is lower than the vapor pressure of the solute water in the surrounding cells and as heat is removed at the freezing point of the solutions, the ice crystals grow between the cells, extracting water from them.

As the ice crystals grow, the volume of the cells shrinks, and the cells are crushed between the ice crystals. Additionally, as the cells shrink, the solutes inside the cells are concentrated in the remaining water, increasing the intracellular ionic strength and interfering with the organization of the proteins and other organized intercellular structures. Eventually, the solute concentration inside the cells reaches the eutectic and freezes. The final state of frozen tissues is pure ice in the former extracellular spaces, and inside the cell membranes a mixture of concentrated cellular components in ice and bound water. In general, this process is not reversible to the point of restoring the tissues to life, although there are occasional exceptions observed in nature (vitrifying polyols (i.e., insects, amphibians), thermal hysteresis proteins (insects, fish).[4] [5]

Clathrate hydrates are a class of solids in which gas molecules occupy "cages" made up of hydrogen-bonded water molecules. These "cages" are unstable when empty, collapsing into conventional ice crystal structure, but they are stabilised by the inclusion of the gas molecule within them. Most low molecular weight gases (including O2, N2, CO2, CH4, H2S, Ar, Kr, and Xe) will form a hydrate under some pressure-temperature conditions.[6]

Live biological tissues can be saturated with the clathrate-forming gas(es) by diffusion or perfusion at the appropriate pressure in the range 1–50 bars at a temperature above clathrate-forming temperature. After saturation, the biological tissue is cooled, first below the clathrate-forming temperature, but above the freezing point of water, then to a temperature where the clatharate is metastable at ambient pressure, and the pressure allowed to go to ambient. The "biological tissue" is then gradually cooled down to some appropriate temperature at normal atmospheric pressure and stored an indefinite time.

The method protects biological tissues by retention of water inside the cells by clathrate formation of the water with the introduced gases, limiting the formation of ice outside the cells.

See also

References

External links


'"/>


(Date:9/30/2014)... 30, 2014 Research by UC Irvine immunologists reveals ... light on a vital process that determines how the ... online version of Nature Immunology , neurology professor ... Institute for Immunology colleagues describe a critical mechanism underlying ... the bloodstream. , A T cell is a type ...
(Date:9/30/2014)... A University of Maryland-led research team has been ... National Institutes of Health (NIH) to develop new ... further our understanding of how large networks of ... information. This knowledge will help researchers identify the ... drive behavior, like decision-making and speaking, and alterations ...
(Date:9/30/2014)... NV (PRWEB) September 30, 2014 EverStryke ... a free introduction to SurvivalLife.com along with a free book ... the attention of Shane Michaels, prompting an investigative review. ... well-known people in the survival and preparation niche, and this ... of the great classes and survival products that Joe offers ...
(Date:9/30/2014)... Elevate , the latest product from ... and out of the gym by providing natural ingredients that ... of Shane Michaels, prompting an investigative review. , “When ... most people simply just don’t have the ability to perform ... work, getting the motivation to finish a project, or even ...
(Date:9/30/2014)... CA (PRWEB) September 30, 2014 ... providers in Turkey has gone up more than 79 ... The medical tourism company also reported total revenue tripled ... 2012. , The company’s professional strategy has allowed them ... — ultimately designed for patient comfort and privacy — ...
Breaking Medicine News(10 mins):Health News:UCI study uncovers important process for immune system development 2Health News:UMD receives inaugural BRAIN Initiative Award 2Health News:EverStryke: Review Exposes Joe Marshall’s Permanent Match Survival Product 2Health News:Elevate: Review Exposes Blue Star Nutraceutical’s Latest Supplement for Ultimate Brain Function, Focus, and Energy 2Health News:VisitandCare.com Announces Record Demand for Plastic Surgery in Turkey 2Health News:VisitandCare.com Announces Record Demand for Plastic Surgery in Turkey 3Health News:VisitandCare.com Announces Record Demand for Plastic Surgery in Turkey 4
... The Disc-Traction ... Therapeutic Belt., LAGUNA BEACH, Calif., Nov. 15 ... little stresses on their,shoulders all year round? Perhaps something designed to ease ... lower back,pain, whether during the holiday season or any other time of ...
... and CHIPPENHAM, England, November 15, Sosei Group ... Group plc ("Vectura"; LSE: VEC) announce the,start, ... study of QVA149 for the treatment,of chronic ... combination of,NVA237, a once-daily long-acting muscarinic antagonist ...
... the United States has health insurance is essential, but ... reform the health system needs, according to a new ... a High Performance Health System. , Guaranteeing affordable health ... health care providers are paid, better organizing and coordinating ...
... Some 225 healthcare,organizations, representing a broad industry spectrum, ... presentation in Las Vegas on,November 4 during the ... eHealthcare Leadership Awards were selected from more,than 1,100 ... healthcare and,the Internet judged the entries. The ...
... Corporation and its former outpatient therapy division,Physiotherapy ... United States $16.6,million to settle allegations that ... federal health care programs, the Justice Department,announced ... Physiotherapy, which is based,in Memphis, Tenn., submitted ...
... holiday season certainly comes,with its share of holiday stress. ... young son or daughter. Here,s more on the difficult ... who has diabetes. Listen to this report from ... Registered journalists can access video, audio, text, graphics ...
Cached Medicine News:Health News:Eliminate Holiday Aches and Pains: The Perfect Gift for Every Back Pain Sufferer on Your List 2Health News:Sosei and Vectura Announce Start of Phase II Studies of QVA149 for the Treatment of COPD 2Health News:Sosei and Vectura Announce Start of Phase II Studies of QVA149 for the Treatment of COPD 3Health News:Commonwealth Fund Commission issues reform recommendations for next president 2Health News:Commonwealth Fund Commission issues reform recommendations for next president 3Health News:Epilepsy.com Wins Silver for Best Patient Care/Disease Management Website at the 2007 eHealthcare Leadership Awards - Honored at Healthcare Internet Conference in Las Vegas 2Health News:Stryker Corp. & Physiotherapy Associates to Pay U.S. $16.6 Million for Alleged False Claims to Federal Health Care Programs 2
Other medicine definitionOther Tags