 Cryopreservation of plant shoots.
 A tank of liquid nitrogen, used to supply a cryogenic freezer (for storing laboratory samples at a temperature of about −150 degrees Celsius). Cryopreservation is a process where cells or whole tissues are preserved by cooling to low sub-zero temperatures, such as (typically) 77 K or −196 °C (the boiling point of liquid nitrogen). At these low temperatures, any biological activity, including the biochemical reactions that would lead to cell death, is effectively stopped. However, when vitrification solutions are not used, the cells being preserved are often damaged due to freezing during the approach to low temperatures or warming to room temperature. Image File history File linksMetadata Download high resolution version (1797x2700, 1486 KB)Cryopreservation of plant shoots. ...
Image File history File linksMetadata Download high resolution version (1797x2700, 1486 KB)Cryopreservation of plant shoots. ...
Image File history File linksMetadata Download high resolution version (1040x1983, 476 KB) File links The following pages link to this file: Nitrogen Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ...
Image File history File linksMetadata Download high resolution version (1040x1983, 476 KB) File links The following pages link to this file: Nitrogen Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ...
Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ...
Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ...
This article includes a list of works cited or a list of external links, but its sources remain unclear because it lacks in-text citations. ...
General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless gas Standard atomic weight 14. ...
Programmed cell death (PCD) is the deliberate suicide of an unwanted cell in a multicellular organism. ...
A vitrification experiment for the study of nuclear waste disposal at Pacific Northwest National Labs Vitrification is a process of converting a material into a glass-like amorphous solid which is free of any crystalline structure, either by the quick removal or addition of heat, or by mixing with an...
Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ...
In physics and chemistry, freezing is the process whereby a liquid turns to a solid. ...
Risks
Phenomena which can cause damage to cells during cryopreservation are solution effects, extracellular ice formation, dehydration and intracellular ice formation. In cell biology, molecular biology and related fields, the word intracellular means inside the cell. It is used in contrast to extracellular (outside the cell). ...
Solution effects Solution effects are caused by concentration of solutes in non-frozen solution during freezing as solutes are excluded from the crystal structure of the ice. High salt concentrations can be very damaging. For other uses, see Salt (disambiguation). ...
Extracellular ice formation When tissues are cooled slowly, water migrates out of cells and ice forms in the extracellular space. Too much extracellular ice can cause mechanical damage due to crushing Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ...
Snowflakes by Wilson Bentley, 1902 Ice is the name given to any one of the 14 known solid phases of water. ...
In cell biology, molecular biology and related fields, the word extracellular means outside the cell. It is used in contrast to intracellular (inside the cell). ...
Dehydration The migration of water causing extracellular ice formation can also cause cellular dehydration. The associated stresses on the cell can cause damage directly.
Intracellular ice formation While some organisms and tissues can tolerate some extracellular ice, any appreciable intracellular ice is almost always fatal to cells. This article does not cite any references or sources. ...
Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ...
In cell biology, molecular biology and related fields, the word extracellular means outside the cell. It is used in contrast to intracellular (inside the cell). ...
In cell biology, molecular biology and related fields, the word intracellular means inside the cell. It is used in contrast to extracellular (outside the cell). ...
Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ...
Prevention of risks Vitrification provides the benefits of cryopreservation without the damage due to ice crystal formation. In clinical cryropreservation, vitrification usually requires the addition of cryoprotectants prior to cooling. The cryoprotectants act like antifreeze: they lower the freezing temperature. They also increase the viscosity. Instead of crystallizing, the syrupy solution turns into an amorphous ice—i.e. it vitrifies. Vitrification of water is promoted by rapid cooling, and can be achieved without cryoprotectants by an extremely rapid drop in temperature (megakelvins per second). The rate that is required to attain glassy state in pure water was considered to be impossible until recently.[1] A vitrification experiment for the study of nuclear waste disposal at Pacific Northwest National Labs Vitrification is a process of converting a material into a glass-like amorphous solid which is free of any crystalline structure, either by the quick removal or addition of heat, or by mixing with an...
A cryoprotectant is a substance that is used to protect biological tissue from freezing damage (damage due to ice formation). ...
Antifreeze is used in gasoline and diesel engines. ...
Quartz crystal Synthetic bismuth hopper crystal Insulin crystals Gallium, a metal that easily forms large single crystals A huge monocrystal of potassium dihydrogen phosphate grown from solution by Saint-Gobain for the megajoule laser of CEA. In chemistry and mineralogy, a crystal is a solid in which the constituent atoms...
Everyday ice is a crystal, which means its molecules are lined up in a repeating pattern. ...
Two conditions usually required to allow vitrification are an increase in the viscosity and a depression of the freezing temperature. Many solutes do both, but larger molecules generally have larger effect, particularly on viscosity. Rapid cooling also promotes vitrification.
In artificial cryopreservation, the solute must penetrate the cell membrane in order to achieve increased viscosity and depressed freezing temperature inside the cell. Sugars do not readily permeate through the membrane. Those solutes that do, such as dimethylsulfoxide, a common cryoprotectant, are often toxic in high concentration. One of the difficult compromises faced in artificial cryopreservation is limiting the damage produced by the cryoprotectant itself. Dimethyl Sulfoxide (DMSO, empirically C2H6OS), also known as methyl sulfoxide or sulfinylbismethane, is a chemical compound. ...
Freezable tissues In general, cryopreservation is easier for thin samples and small clumps of individual cells, because these can be cooled more quickly and so require lower doses of toxic cryoprotectants. Therefore, the goal of cryopreserving human livers and hearts for storage and transplant is still some distance away. Toxic redirects here, but this is also the name of a song by Britney Spears; see Toxic (song) Look up toxic and toxicity in Wiktionary, the free dictionary. ...
The liver is an organ present in vertebrates and some other animals. ...
The heart and lungs, from an older edition of Grays Anatomy. ...
An organ transplant is the transplantation of an organ (or part of one) from one body to another, for the purpose of replacing the recipients damaged or failing organ with a working one from the donor. ...
Nevertheless, suitable combinations of cryoprotectants and regimes of rapid cooling and rinsing during warming often allow the successful cryopreservation of biological materials, particularly cell suspensions or thin tissue samples. Examples include:
- Semen (which can be used successfully almost indefinitely after cryopreservation),
- Blood (special cells for transfusion, or stem cells)
- Tissue samples like tumors and histological cross sections
- Human eggs (oocytes) See oocyte cryopreservation
- Human embryos that are 2, 4 or 8 cells when frozen (pregnancies have been reported from embryos stored for 9 years. Many studies have evaluated the children born from frozen embryos, or “frosties”. The result has uniformly been positive with no increase in birth defects or development abnormalities.)[1]
In addition, efforts are underway to preserve humans cryogenically, known as cryonics. In such efforts either the brain within the head or the entire body may undergo the above process. Cryonics is in a different category from the aforementioned examples, however, for while many cryopreserved cell suspensions, thin tissue samples, and some small organs have been warmed and successfully used, this has not yet been the case for cryopreserved brains or bodies. Proponents of cryonics make a case that cryopreservation using present technology, particularly vitrification of the brain, may be sufficent to preserve people in an "information theoretic" sense so that they could be revived and made whole by vastly advanced future technology. Horse semen being collected for breeding purposes. ...
Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...
Mouse embryonic stem cells with fluorescent marker. ...
Tumor or tumour literally means swelling, and is sometimes still used with that meaning. ...
A thin section of lung tissue stained with hematoxylin and eosin. ...
An oocyte or ovocyte is a female gametocyte or germ cell involved in reproduction. ...
// ICSI sperm injection into oocyte Human Oocyte cryopreservation (egg freezing) is a rapidly advancing, breakthrough technology in which a woman’s eggs (oocytes) are extracted, frozen and stored. ...
Categories: Biology stubs | Developmental biology ...
Technicians prepare a patient for cryopreservation. ...
Information-theoretic death is the destruction of the human brain, and information within it, to such an extent that recovery of the original mind and person that occupied the brain is theoretically impossible. ...
Natural cryopreservation Water bears (or tardigrada), microscopic multicellular organisms, can survive freezing at low temperatures by replacing most of their internal water with the sugar trehalose. Sugars and other solutes that do not easily crystallize have the effect of limiting the stresses that damage cell membranes. Trehalose is a sugar that does not readily crystallize. Mixtures of solutes can achieve similar effects. Some solutes, including salts, have the disadvantage that they may be toxic at high concentrations. Classes Heterotardigrada Mesotardigrada Eutardigrada Tardigrades (Tardigrada), or water bears, are a phylum of small, segmented animals, similar and related to the Arthropods. ...
Classes Heterotardigrada Mesotardigrada Eutardigrada Tardigrades (Tardigrada), or water bears, are a phylum of small, segmented animals, similar and related to the Arthropods. ...
In physics and chemistry, freezing is the process whereby a liquid turns to a solid. ...
Magnification of grains of sugar, showing their monoclinic hemihedral crystalline structure. ...
Trehalose also known as mycose is a 1-alpha (disaccharide) sugar found extensively but not abundantly in nature. ...
Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ...
A biological membrane or biomembrane is an enclosing or separating tissue which acts as a barrier within or around a cell. ...
History One of the most important early workers on the theory of cryopreservation was James Lovelock of Gaia theory fame. Dr. Lovelock's work suggested that damage to red blood cells during freezing was due to osmotic stresses. Lovelock in early 1950s had also suggested that increasing salt concentrations in a cell as it dehydrates to lose water to the external ice might cause damages to the cell.[2] James Lovelock in front of a statue of Gaia in 2000 Dr James Ephraim Lovelock, CH, CBE, FRS (born 26 July 1919) is an independent scientist, author, researcher, environmentalist, and futurologist who lives in Cornwall, in the south west of Great Britain. ...
The Gaia hypothesis, a hypothesis put forward to explain a number of paradoxes about life and the earth was first formulated in the 1960s, by the independent research scientist James Lovelock. ...
Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...
Osmosis is the net movement of water across a partially permeable membrane from a region of high solvent potential to an area of low solvent potential, up a solute concentration gradient. ...
References - ^ Bhat SN, Sharma A, Bhat SV (2005). "Vitrification and glass transition of water: insights from spin probe ESR". Phys Rev Lett 95 (23): 235702. PMID 16384318.
- ^ Mazur P (1970). "Cryobiology: the freezing of biological systems". Science 168 (934): 939-49. PMID 5462399.
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