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Query: UNIPROT:P30536 (PBS)
 9,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The DNA isolated from rat virogenic XC cells transformed by Rous sarcoma virus retains standard transfecting activity for 7 months when the DNA solution in 0.1 X PBS, containing 10% glycerol is stored at -70 degrees C. The value of the sedimentation constant S20w does not significantly change during storage.
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PMID:Long-term preservation of transfecting activity of DNA isolated from rat virogenic XC cells transformed by Prague strain of Rous sarcoma virus. 17 78

The discovery of glycerol as an effective cryoprotectant for spermatozoa led to research on cryopreservation of embryos. The first successful offspring from frozen-thawed embryos were reported in the mouse and later in other laboratory animals. Subsequently, these techniques were applied to domestic animals. Research in cryopreservation techniques have included studies concerning the type and concentration of cryoprotectant, cooling and freezing rates, seeding and plunging temperatures, thawing temperatures and rates, and methods of cryoprotectant removal. To date, successful results based on pregnancy rates have been obtained with cryopreserved cow, sheep, goat, and horse embryos but no success has been reported in swine. Post-thaw embryo survival has been shown to be dependent on the initial embryo quality, developmental stage, and species. The freezing techniques most frequently used in research and by commercial companies are identified as "equilibrium" cryopreservation. In this technique the embryos are placed in a concentrated glycerol solution (1.4 M in PBS supplemented with BSA) at room temperature and the glycerol is allowed to equilibrate for a 20-min period. During the cooling process the straws are seeded (-4 to -7 degrees C) and cooling is continued at a rate of 0.3 to 0.5 degree C/min to -30 degrees C when bovine embryos may be plunged into LN2. Sheep embryos are successfully frozen with ethylene glycol (1.5 M) or DMSO (1.5 M) rather than with glycerol. Horse embryos have been frozen in 0.5 rather than 0.25 cc straws but with cooling rates and seeding and plunging temperatures similar to those used with bovine embryos. Swine embryos have shown a high sensitivity to temperature and cryoprotectants probably due to their high lipid content and a temperature decrease to 15 or 10 degrees C causes a dramatic increase in the percentage of degenerated embryos. However, a recent study has shown that hatched pig blastocysts survived exposure below 15 degrees C. Recent research has shown that embryos may also be frozen by a "nonequilibrium" method. This rapid freezing by vitrification consists of dehydration of the embryo at room temperature by a very highly concentrated vitrification media (3.5 to 4.0 M) and a very rapid freeze that avoids the formation of ice allowing the solution to change from a liquid to a glassy state. Vitrification solutions consist of combinations of sucrose, glycerol, and propylene glycol. With this technique, 50% pregnancy rates have been reported with the bovine blastocyst.
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PMID:Status of cryopreservation of embryos from domestic animals. 160 26

Most techniques used to visualize cells in tissues are accompanied by some distortion of the tissue due to fixation and sectioning. We here present a technique involving "optical sectioning" and three-dimensional reconstruction of fluorescence-labelled Langerhans' cells in human skin that avoids such problems. The instrument used to study the specimens was a PHOIBOS Confocal Scanning Laser Microscope (CSLM) built around a Zeiss Universal microscope. A software package for three-dimensional reconstructions of confocal sections was employed for calculations in a Hewlett-Packard HP9000-350 minicomputer running UNIX. Normal human skin obtained at plastic surgery or skin biopsy specimens from allergic, irritant, or control patch test reactions was studied. Epidermis separated from dermis by incubation in thermolysin or thick (25 microns) cryostat sections were incubated with fluorescein-isothiocyanate labelled mouse monoclonal antibodies directed against HLA-DR. To reduce the fading of immunofluorescence during microscopy, the specimens were mounted with glycerol in PBS containing p-phenylenediamine. The results indicate that CSLM is a powerful tool for investigations on Langerhans' cells in different conditions of the skin allowing a three-dimensional view of cells in unfixed or acetone-fixed preparations at the light microscope level.
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PMID:Three-dimensional visualization of human Langerhans' cells using confocal scanning laser microscopy. 218 43

Spermatozoa from cauda epididymis of mature mice were suspended in preservation solution (Dulbecco's PBS containing raffinose in combination with glycerol, DMSO or skim milk as freezing protective agents). The suspension was frozen by the dry ice-alcohol method and preserved for 1-120 days in liquid nitrogen (-196 degrees C). Highest sperm viability after thawing was obtained with a combination of 10% raffinose and 5% glycerol or with a combination of 10% raffinose and 10% DMSO. These frozen thawed sperm were found to have fertilizing capacity when used for in vitro fertilization. The 2-cell embryos obtained through the above procedures developed into normal pups at a high rate when transferred into the oviducts of pseudopregnant female mice.
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PMID:[Production of normal young following transfer of mouse embryos obtained by in vitro fertilization using cryopreserved spermatozoa]. 230 89

The separate effects of five influence factors and their coupled interactions on cryoinjury of human erythrocytes were investigated experimentally and statistically. The five factors, each having three levels, were as follows: (1) cooling rate: -0.5, -140, and -800 degrees C/min; (2) warming rate: +0.5, +25, and +200 degrees C/min; (3) hematocrit: 2, 11, and 60%; (4) concentration of cryoprotectant (glycerol): 1, 2, and 4 M in PBS; and (5) holding temperature at which the frozen samples were kept: no hold, -75 degrees C for 1.5 hr, and -196 degrees C for 1.5 hr. Twenty-seven special tests, which were chosen from the 243 possible tests by using the Fractional Factorial Design Technique, an optimum seeking technique, were performed. The conclusions are: (1) the cooling rate is the most significant or sensitive factor causing cryoinjury to the cells; (2) the main effects of the hematocrit and the concentration of cryoprotectant, the interaction between the cooling rate and the warming rate, and the interaction between the cooling rate and the concentration of cryoprotectant are next most significant; (3) the main effect of warming rate, and the interaction between the holding temperature and the cooling rate are less significant; (4) the holding temperature below -75 degrees C, and the remaining interactions between two factors are relatively not significant; and (5) in the present study, the optimal combination of the five factors for the survival of the cells is: cooling at -0.5 degrees C/min, warming at +0.5 degrees C/min, hematocrit at 11%, glycerol concentration at 4 M in PBS, and holding temperature below -75 degrees C.
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PMID:A study of the separate effects of influence factors and their coupled interactions on cryoinjury of human erythrocytes. 276 83

Embryos (8-16 cell) were obtained from random bred albino mice (6-8 weeks old) that were induced to superovulate by injections of 5 I.U. PMSG and 5 I.U. hCG given 48 hr apart. Embryos were exposed to intracellular cryoprotecting medium (glycerol 10%, 1-2 propanediol 20% in PBS) for 10 min and then transferred to extracellular vitrification medium (25% glycerol, 25% 1-2 propanediol in PBS). Vitrification medium containing embryos, and diluent (1 M sucrose) were loaded in a straw and immediately plunged into liquid N2. After thawing at 20 degrees C, the contents of the straw were mixed by shaking (1 step dilution) and emptied in a petri dish. After 3 washings in culture medium the embryos were kept in CO2 incubator for further development. In 3-step dilution procedure the dilution of cryoprotectants was done in 0.5 and 0.25 M sucrose before culture. Embryos in 3-step dilution of cryoprotectants exhibited high survival as compared to 1-step dilution (20.23% vs 6.55%).
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PMID:Cryopreservation of mouse embryos at -196 degrees C by vitrification. 280 16

Murine embryos of mice of four different inbred strains and one hybrid strain were evaluated for their ability to survive quick freezing by post-thaw in vitro development. The embryos were transferred to an equilibration medium [10% 1,2-propanediol and 20% glycerol in modified PBS (mPBS)] for 10 minutes and frozen in a vitrification medium (25% glycerol and 25% 1,2-prapanediol in mPBS) by direct lowering into liquid nitrogen. Following thawing at 30 degrees C, dilution in 1 M sucrose in mPBS and washing in mPBS the embryos were cultured, and development was evaluated 24-28 hours later. The number of fertilized eggs obtained by superovulation differed among the strains. The survival rates evaluated by in vitro cultivation of the post-thawed inbred embryos varied from 50-85% depending on the genotype, whereas the normal live offspring from transfer of frozen-thawed embryos to recipient females confirms that the quick freezing method is an applicable method for storage of genetically defined mouse strains and stocks. The quick freezing technique was applied on 4- and 8-cell (day-3) mouse embryos of hybrids. The in vitro development of frozen thawed 4- and 8-cell embryos (23% and 21% respectively) was found to be significantly lower than that of frozen thawed morulae (89%). Permeation in glycerol-solutions before equilibration significantly increased survival of 4- and 8-cell embryos (66% and 77% respectively). By the use of dimethylsulfoxid (DMSO) in the permeation solutions an even higher survival rate was obtained in the cryopreservation of 8-cell mouse embryos (95%).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Quick freezing of mouse embryos: freezing of inbred strains and 2- and 4-cell embryos by vitrification. 297 55

We have studied the methods of cryopreservation and dilution of the unfertilized and fertilized eggs of ICR mouse. To improve the survival rate, we examined 8 types of methods with various combination of cryoprotectants, dilutions and cooling rates. The highest survival rate for unfertilized eggs was obtained when 1.5 M dimethylsulfoxide (DMSO) + 0.25 M sucrose was added to PBS as a cryoprotectant and when the eggs were diluted by adding PBS with 0.5 M sucrose at room temperature at 5-minute intervals in 5 steps. The total survival rate was 45.4% (p less than 0.01). In the case of fertilized eggs, the highest survival rate (72.6%) was obtained with 10% glycerol + 0.25 M sucrose as a cryoprotectant and a One-step dilution method. The most effective cooling rate was 0.3 degrees C per minute for either unfertilized or fertilized eggs.
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PMID:[Effects of cryoprotectants and sucrose dilution on the survival of unfertilized and fertilized mouse eggs after freezing and thawing]. 337 73

Several concentrations of trehalose (0.0, 0.04, 0.1, 0.25 M) in combination with three concentrations of glycerol (1.0, 1.5, 2.0 M) were evaluated for the cryopreservation of murine embryos. Embryos were transferred through increasing concentrations of glycerol in Dulbecco's phosphate-buffered saline with 10% fetal calf serum (PBS + FCS) to reach the final glycerol concentrations. They were then randomly assigned to one of the concentrations of trehalose. A total of 506 morulae were packaged individually in 0.25-ml plastic straws and cooled from ambient temperature at 1.0 degrees C/min in a programmable methanol freezer. Embryos were seeded at -7 degrees C and then cooled to -25 degrees C at 0.3 degrees C/min before being plunged into liquid nitrogen. After thawing and a one-step dilution of glycerol, embryos were cultured for 48 hr and viability was determined by blastocoel formation. Highest viability (70.0%) after 48 hr in culture was obtained for embryos frozen in 1.5 M glycerol plus 0.10 M trehalose as compared to 31% viability for embryos frozen with glycerol alone. These observations suggest that trehalose can be used in combination with glycerol as a cryoprotectant and that a high rate of viability can be achieved after a one-step dilution of the cryoprotectants.
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PMID:Cryopreservation of murine embryos with trehalose and glycerol. 340 7

High-performance hydrophobic interaction chromatography (HP-HIC) was found to be an effective method for the separation of lectins into isolectin fractions. All of the purified lectins used in this study, Phaseolus vulgaris haemagglutinin (PHA), wheat germ agglutinin (WGA), Ricinus communis agglutinin (RCA), and Arachis hypogaea agglutinin (AHA), were prepared by affinity chromatography. HP-HIC was performed on a column (15 X 2.1 cm) of TSK gel Phenyl-5PW at room temperature. The lectin sample, dissolved in 1.0 or 0.5 M ammonium sulphate in phosphate buffered saline (pH 7.4) (PBS), was applied to the column and eluted with a linear gradient from 1.0 or 0.5 M ammonium sulphate in PBS to 0 M ammonium sulphate in PBS at a flow-rate of 4 ml/min. In the case of RCA, addition of glycerol to the elution buffer resulted in sharper isolectin peaks. PHA, WGA, RCA, and AHA were rapidly separated into 5, 5, 4, and 6 isolectins, respectively.
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PMID:Separation of isolectins by high-performance hydrophobic interaction chromatography. 366 61


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