X-Message-Number: 29910 Date: Fri, 12 Oct 2007 09:31:11 -0700 (PDT) From: Subject: 3-O-methyl-D-glucose may enable fully reversible cryopreserva... [Alas, this is not at all likely due to the high price for 3-O-methyl-D-glucose of $1,500 per gram. One is reminded of the cryoprotective superiority of DESO over DMSO. Despite this superiority no further research has been published on DESO since 2004. Guess which is vastly more expensive: DESO or DMSO?] http://www.omicronbio.com/al-mg.php Tissue Eng. 2006 Jul;12(7):1873-9. 3-O-methyl-D-glucose improves desiccation tolerance of keratinocytes. Norris MM, Aksan A, Sugimachi K, Toner M. Surgical Services and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA. Transplantation of autologous skin grafts and tissue engineered skin replacements for the treatment of burns, trauma, and ulcerative wounds has been shown to restore a protective barrier to infection and fluid loss, reduce heat loss, provide mechanical strength, diminish pain, and dampen the hypermetabolic stress response to thermal injury. Patencies of these grafts depend mainly on the high viability and sustained function of the enmeshed keratinocytes. With growing demand in tissue replacement therapies, development of successful and economical preservation techniques for skin grafts and replacements becomes essential. In this regard, if attained, desiccated state storage offers an economical solution to availability, storage, and transportation problems. Recent studies indicate that carbohydrates are very efficient in stabilizing mammalian cells against various types of stresses, including those associated with cryopreservation and desiccation. In this study we introduce the use of 3-O-methyl-D-glucose (3-OMG), a nonmetabolizable glucose derivative, as a new means of providing protection for keratinocytes undergoing desiccation. We show that with decreasing water contents, viability of the cells decreases; however, at the same water content the immediate post-rehydration viability and long-term survival of the cells exposed to 3-OMG are much higher than those of controls. PMID: 16889517 Tissue Eng. 2006 Mar;12(3):579-88. Nonmetabolizable glucose compounds impart cryotolerance to primary rat hepatocytes. Sugimachi K, Roach KL, Rhoads DB, Tompkins RG, Toner M. Harvard-MIT Division of Health Sciences and Technology, Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA. We herein report a novel method for the cryopreservation of hepatocytes using a non-metabolizable glucose derivative in an attempt to mimic the natural cryoprotective adaptations observed in freeze-tolerant frogs. Primary rat hepatocytes were loaded with 3-O-methyl glucose (3OMG) through endogenous glucose transporters without evident toxicity. The 3OMG-loaded hepatocytes were then frozen in a controlled rate freezer down to -80 degrees C and stored in liquid nitrogen at -196 degrees C. Hepatocytes cryopreserved with a relatively small amount of intracellular 3OMG (<0.2 M) showed high post-thaw viability and maintained long-term hepatospecific functions, including synthesis, metabolism, and detoxification. Metabolite uptake and secretion rates were also largely preserved in the cryopreserved hepatocytes. This is the first study to demonstrate the use of the non-metabolizable glucose derivative 3OMG in hepatocyte cryopreservation. PMID: 16579691 Cryobiology. 2004 Aug;49(1):1-9. Glass-forming property of the system diethyl sulphoxide/water and its cryoprotective action on Escherichia coli survival. Markarian SA, Bonora S, Bagramyan KA, Arakelyan VB. Department of Chemistry, Yerevan State University, 375049 Yerevan, Armenia. In this work the thermal properties of diethyl sulphoxide (Et2SO), as well as its cryoprotective ability are studied and related to other well-known cryoprotectant substances, like dimethyl sulphoxide (Me2SO). We have investigated the thermal properties of Et2SO/water systems using Differential Scanning Calorimetry at a very low heating/cooling rate (2 degrees C/min). Liquid/solid or glassy/crystalline transitions have been observed only for the solutions with content of Et2SO ranging from 5 up to 40% w/w and/or greater than 85%. In the 45-75% w/w Et2SO range we have found a noticeable glass-forming tendency and a great stability of the amorphous state to the reheating. In samples with Et2SO content ranging from 80 to 85%, we observed a great stability of the glass forming by cooling, but a lesser stability to the subsequent reheating. The glass-forming tendency of these solutions is discussed in terms of existing competitive interactions between molecules of Et2SO, on the one hand, and Et2SO and water molecules, on the other hand. The results are well explainable on the basis of the model structure of water/Et2SO solutions, deduced by Raman and infrared studies [J. Mol. Struct. 665 (2003) 285-292]. The cryoprotective ability of Et2SO on Escherichia coli survival has been also investigated, and a comparison among Et2SO and other widely used cryoprotectants, like Me2SO and glycerol has been done. Survival of E. coli, determined after freezing-thawing process, was maximal at 45% w/w Et2SO (more than 85% viability). It should be noted that at the same concentration the survival is only about 35% in the presence of Me2SO and not more than 15% in the presence of glycerol. These features are well consisted with the glass-forming properties of Et2SO. PMID: 15265712 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=29910