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B Balint

Publications and source records attributed to B Balint.

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PubMedDate not supplied

[Current knowledge on cryopreservation of spermatozoa, ovum cells and zygotes].

CELL INJURIES DURING FREEZING AND THAWING: The aim of various cryopreservation procedures is to minimize cell injuries during the freeze-thaw cycle (cryoinjuries). Generally, the cell damage during freezing and thawing procedures may be the results of: (a) extensive cellular dehydration (solution effect) and/or (b) intracellular ice crystallization/recrystallization (mechanical cell damage). Two independent mechanisms are involved. They can act simultaneously, leading to cytolysis. The first one is expressed primarily during low rate freezing, and the second one during rapid freezing. Thus, determination and use of the optimal cooling velocity, specific for each type of isolated cells, should be considered. Finally, a higher degree of cell destruction has been documented when the transition period from liquid to solid phase (release of the fusion heat) is prolonged. CRYOPROTECTIVE AGENTS: For successful cell cryopreservation, cryoprotectants are needed. They decrease the osmotic gradient and the vapor pressure difference between the intra- and extracellular area. Adequate choice of the most suitable type and concentration of cryoprotective agent is important for the required cell recovery after thawing. There are several well known protocols for obtaining cryopreservation of isolated cells using different cryoprotectants. Glycerol, dimethyl sulfoxide (DMSO) and propanediol sucrose are commonly used as cryoprotectants, though in different concentrations. Glycerol, a trihydric alcohol, is a clear, colorless fluid. Pharmacologically, it is relatively inert. DMSO is a colorless liquid with a sulphur-like smell and has several medical uses. It is highly polar and dissolves many water- and lipid-soluble substances. DMSO given intravenously may cause nausea, vomiting, local vasospasm and an objectionable garlic-like odor and taste. HUMAN SPERM, OVA AND EMBRYOS CRYOPRESERVATION: Despite the fact that cryopreservation procedures of spermatozoa, ova and embryos are already in routine clinical use, some questions related to the optimal cooling velocity during controlled-rate freezing and the choice of the most effective, either penetrating (glycerol, dimethyl sulfoxide) and/or non-penetrating (hydroxyethyl starch) cryoprotective agent at the appropriate concentration are not resolved.

Cryopreservation↗
PubMedDate not supplied

[Use of fibrin glue prepared from recycled cryoprecipitate in experimental liver surgery].

Fibrin glue (FG) is a two-component biologic system with adhesive, sealant and topical hemostatic properties, containing fibrinogen (Fg), factor XIII (FXIII), fibronectin (Fn), thrombin, some antifibrinolytic agent if needed and ionized calcium. In this study, FG component 1 was prepared by recycling cryoprecipitation from single-donor plasma. The mean concentrations of Fg, FXIII and Fn were: 54.2 +/- 19.9 g/l, 8.03 +/- 2.3 IU/ml and 3103.1 +/- 148.91 mg/l, respectively. Horizontal tensile strength of FG was 1.076 +/- 0.18 N/cm2 in the average. Using a rat model, the efficacy of the FG-treatment in liver surgery was evaluated on the basis of the 24 hour survival ratio and hematological parameters of the experimental animals and control group. Survival of rats subjected to partial and total lobectomy and FG-treated was significantly (p < 0.001) higher than in FG-non-treated animals. Survival of animals subjected to liver incision was not significantly different, although the differences in hematological parameters were significant (p < 0.001 to p < 0.09) in favor of FG-treated animals. Our findings confirmed that high quality FG can be prepared by recycling cryoprecipitation from single-donor plasma--with sufficient yield of fibrinogen, FXIII and fibronectin and with the risk of disease transmission not greater than with the use of single unit of blood or plasma--which have efficient hemostatic and therapeutic properties.

Animals↗