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  • 1
    Electronic Resource
    Electronic Resource
    Unit gravity sedimentation separation of cells comprising the caput epididymidis of the rat (1977)
    Springer
    Cell & tissue research 183 (1977), S. 371-378 
    Details
    ISSN: 1432-0878
    Keywords: Epididymis, rat ; Epithelium, isolation ; Unit gravity sedimentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cells from the rat caput epididymidis were separated by unit gravity sedimentation. Purest 12-ml fractions contained 88–95% basal cells or 64–76% principal cells. Ultrastructure of separated cells was similar to that of cells in intact tissue. Viability of separated cells was excellent as determined by dye exclusion tests and cellular ATP content. By combining fractions pools containing 4.0±0.9 × 106 cells (86±8% basal cells) and 1.4±0.4 × 106 cells (56±7% principal cells) were obtained. Thus, studies on the function of basal and principal cells from the rat caput epididymidis should be possible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220643
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  • 2
    Electronic Resource
    Electronic Resource
    Use of a monoclonal antibody to evaluate integrity of the plasma membrane of stallion sperm (1988)
    New York, NY : Wiley-Blackwell
    Gamete Research 21 (1988), S. 233-241 
    Details
    ISSN: 0148-7280
    Keywords: spermatozoa ; acrosome ; F79.3E2 ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Transmission electron microscopy was used to confirm that a monoclonal antibody (F79.3E2; class IgGlK) was specifically localized to an antigen in the acrosomal ground substance of stallion sperm. This antibody was used to develop and validate an indirect immunofluorescent procedure to evaluate integrity of the plasma-acrosomal membranes of stallion sperm. The concept was that primary monoclonal antibody would be “shielded” from its acrosomal antigen by an intact plasma membrane. Conversely, sperm with damaged plasma-acrosomal membranes would exhibit green acrosomal fluorescence when viewed with an epifluorescence microscope. A lipophilic counterstain (red fluorescence) was used to insure that all sperm were visualized. Sperm in fresh-extended or frozen-thawed semen were incubated with hybridoma supernatant containing monoclonal antibody for 30 min at 37°C, then a second antibody (rabbit anti-mouse IgG-FITC) was added for 30 min at 37°C. Unbound antibody was removed by dilution and centrifugation. Sperm were resuspended in phosphate-buffered saline containing Evan's blue as a counterstain. All sperm fluoresced bright red, regardless of the status of cell membranes, except that in cells with damaged plasma-acrosomal membranes, the green fluorescence associated with antibody was overriding for the rostral portion. By counting fluorescent and nonflourescent “acrosomes”, the percentage of sperm with intact plasma-acrosomal membranes was easily determined. Evaluation of five mixtures of undamaged and damaged sperm by this procedure gave a correlation of 0.91 between the percentage of damaged sperm in a mixture and the percentage of sperm with a fluorescent acrosome. Intra- and interassay coefficients of variability were 〈 6%.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120210305
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  • 3
    Electronic Resource
    Electronic Resource
    The retention of 125I-labeled plasma membrane proteins in bovine spermatozoa cryopreserved in egg-yolk citrate extender (1985)
    New York, NY : Wiley-Blackwell
    Gamete Research 11 (1985), S. 367-377 
    Details
    ISSN: 0148-7280
    Keywords: bovine sperm ; cryopreservation ; plasma membrane ; protein loss ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Cryopreservation of bovine sperm in egg-yolk citrate extender (EYC) usually maintains fertility. Since plasma membrane proteins are important for the fertilizing potential of sperm, the possible loss of membrane proteins from sperm subjected to cryopreservation in EYC was evaluated. Sperm were washed and labeled with 125I without significantly reducing motility. Radiolabeled sperm were a) held for 2 hr at 22°C in N-2-hydroxyethylpiperazine-N'-ethanesulfonic acid (HEPES)-buffered saline containing 1% polyvinyl alcohol, b) cooled to 5 °C in glycerol-free EYC and held for 3 hr, or c) frozen-thawed in EYC containing 7% glycerol. Sperm were solubilized and proteins were separated by electrophoresis under denaturing conditions. Freeze-thawing dislodged most egg-yolk proteins from the spermatozoal plasma membrane that were bound to and retained by sperm that only were cooled to 5 °C. Autoradiography resolved 11-18 bands of 125I polypeptides. There was no difference (P 〉 0.05) in the amount of 125I protein retained by frozenthawed and cooled sperm. However, the radioactivity in two polypeptide bands (MW = 105 K and 24.2 K) was less (P 〈 0.05) for sperm held at 22 °C in HEPES-buffered saline. Thus, holding sperm in buffered saline at 22 °C resulted in a greater loss of 125I proteins from the plasma membrane than did cryopreservation of sperm in EYC. Cryopreservation did not induce greater loss of 125I proteins from the plasma membrane than simply cooling sperm to 5 °C in EYC.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120110404
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  • 4
    Electronic Resource
    Electronic Resource
    Effects of exposing bovine sperm to bovine serum albumin, or freeze-thawing, on sperm-bound amidase activity (1987)
    New York, NY : Wiley-Blackwell
    Gamete Research 17 (1987), S. 213-219 
    Details
    ISSN: 0148-7280
    Keywords: membrane integrity ; cryopreservation ; acrosin ; micro-assay ; sperm isolation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Isolation of a self-selected population of motile spermatozoa is possible by using a gradient of bovine serum albumin (BSA). We determined if exposure to BSA altered the sperm or if isolated sperm differed from nonisolated cells in terms of motility or activity of sperm-bound amidase, either before or after subsequent cryopreservation. Exposure of sperm to 6% BSA in egg yolk Tris extender induced changes in the plasma and acrosomal membranes of sperm that resulted in exposure and activation of sperm-bound amidase (P 〈 .01). In experiment 2, semen extended in egg yolk Tris was cooled to 5°C or layered onto a solution of 6% BSA in extender at 37°C, from which the sperm that had swum into the BSA solution were recovered 2 h later and cooled to 5°C. Sperm in both treatments were cryopreserved. The percentage of progressively motile sperm was determined visually and by track motility. Activity of sperm-bound amidase exposed to substrate was evaluated. After recovery of sperm from the 6% BSA solution, 81% were progressively motile as compared to 59% in the starting samples (P 〈 .01). However, the amount of exposed sperm-bound amidase also was greater (P 〈 .05) this was a deleterious change. Immediately after thawing, more (P 〈 .01) sperm were motile in samples of isolated sperm than for nonisolated cells (43 vs 24%), but after incubating the thawed sperm for 1 h at 37°C there was no difference. After freezing and thawing of sperm, amidase activity was higher (P 〈 .05) for the isolated sperm than for nonisolated cells. Thus, isolation of sperm using a 6% BSA gradient increased the proportion of progressively motile sperm, but decreased the percentage of sperm with an intact acrosome, based on measurements of amidase activity.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120170304
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  • 5
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    Experiment K-7-16: Effects of Microgravity or Simulated Launch on Testicular Function in Rats (1994)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: Fixed or frozen testicular tissues from five rats per group were analyzed by: subjective and quantitative evaluations of spermatogenesis; Northern-blot analysis for expression of selected genes; quantification of testosterone and receptors for LH; and morphometric analysis of Leydig cells. Based on observations of fixed tissue, it was evident that some rats in the flight and vivarium groups had testicular abnormalities unassociated with treatment, and probably existing when they were assigned randomly to the four treatment groups; the simulated-launch group contained no abnormal rat. Lesions induced in testes of caudal-elevation rats precluded discernment of any pre-existing abnormality. Considering rats without pre-existing abnormalities, diameter of seminiferous tubules and numbers of germ cells per tubule cross section were lower (E less than 0.05) in flight rats than in simulated-launch or vivarium rats. However, ratios of germ cells to each other, or to Sertoli cells, and number of homogenization-resistant spermatids did not differ from values for simulated-launch or vivarium controls. There was no effect of flight on normal expression of testis-specific hsp gene products, or evidence for production of stress-inducible transcripts of the hsp70 or hsp90 genes. Concentration of receptors for rLH in testicular tissue, and surface densities of smooth endoplasmic reticulum and peroxisomes in Leydig cells, were similar in flight and simulated-launch rats. However, concentrations of testosterone in testicular tissue or peripheral blood plasma were reduced (P less than 0.05) in flight rats to less than 20 percent of values for simulated-launch or vivarium controls. Thus, spermatogenesis was essentially normal in flight rats, but production of testosterone was severely depressed. Sequela of reduced androgen production on turnover of muscle and bone should be considered when interpreting data from mammals exposed to microgravity.
    Keywords: Life Sciences (General)
    Type: US Experiments Flown on the Soviet Biosatellite Cosmos 2044; 3-24; NASA-TM-108802
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  • 6
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    Effects of microgravity or simulated launch on testicular function in rats (1992)
    In:  Other Sources
    Details
    Publication Date: 2019-08-28
    Description: Reproductive toxicology and cellular and molecular biology approaches were used to evaluate testicular function in rats from Cosmos 2044. It is found that concentrations of testosterone in testicular tissue or peripheral blood plasma were reduced in flight rates to less than 20 percent of values for simulated-launch or vivarium controls. Spermatogenesis was essentially normal in flight rats, but production of testosterone was severely depressed.
    Keywords: LIFE SCIENCES (GENERAL)
    Type: Journal of Applied Physiology, Supplement (ISSN 8750-7587); 73; 2 Au
    Format: text
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  • 7
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    Effects of Caudal Elevation on Testicular Function in Rats: Separation of Effects on Spermatogenesis and Steroidogenesis (1992)
    In:  CASI
    Details
    Publication Date: 2019-08-16
    Description: A variety of biologic processes are perturbed when exposed to microgravity (space flight) for more than 7 days, including testicular function. Suspension of rats in a special harness (caudal elevation) to induce thoracic pooling of blood fluids and remove the support function of the hind limbs is used to mimic, on earth, the effects of microgravity encountered during space flight. Typically, this induces cryptorchidism in male rats. Three experiments were conducted to differentiate the effects of caudal elevation (30 deg angle) and anatomic location of testes on spermatogenesis and steroidogenesis. Rats were subjected to caudal elevation for 7 days using either a tail harness or a whole-body harness. Testes of rats fell into the abdominal cavity when a tail harness was used, but ligation of the iguinal canal prevented this repositioning. For rats with abdominal testes, testicular weight was reduced (P less than 0.05) and histology of testes was abnormal; the number of spermatids per gram parenchyma was lower (P less than 0.05) in tail-suspended rats compared with control rats.
    Keywords: Life Sciences (General)
    Type: NASA/CR-1992-205174 , NAS 1.26:205174 , Journal of Andrology; 13; 3; 224-231
    Format: application/pdf
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  • 8
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    Effects of Microgravity or Simulated Launch on Testicular Function in Rats (1992)
    In:  CASI
    Details
    Publication Date: 2019-08-16
    Description: Testes from flight rats on COSMOS 2044 and simulated-launch, vivarium, or caudal-elevation control rats (5/group) were analyzed by subjective and quantitative methods. On the basis of observations of fixed tissue, it was evident that some rats had testicular abnormalities unassociated with treatment and probably existing when they were assigned randomly to the four treatment groups. Considering rats without preexisting abnormalities, diameter of seminiferous tubules and numbers of germ cells per tubule cross section were lower (P less than 0.05) in flight than in simulated-launch or vivarium rats. However, ratios of germ cells to each other or to Sertoli cells and number of homogenization-resistant spermatids did not differ from values for simulated-launch or vivarium controls. Expression of testis-specific gene products was not greatly altered by flight. Furthermore, there was no evidence for production of stress-inducible transcripts of the hsp7O or hsp9O genes. Concentration of receptors for rat luteinizing hormone in testicular tissue and surface density of smooth endoplasmic reticulum in Leydig cells were similar in flight and simulated-launch rats. However, concentrations of testosterone in testicular tissue or peripheral blood plasma were reduced (P less than 0.05) in flight rats to less than 20% of values for simulated-launch or vivarium controls. Thus spermatogenesis was essentially normal in flight rats, but production of testosterone was severely depressed. Exposure to microgravity for more than 2 wk might result in additional changes. Sequelae of reduced androgen production associated with microgravity on turnover of muscle and bone should be considered.
    Keywords: Life Sciences (General)
    Type: NASA-CR-204998 , NAS 1.26:204998 , (ISSN 0161-7567); 174S-185S
    Format: application/pdf
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