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  • 1
    Digitale Medien
    Digitale Medien
    Amino acid sequence around the single 3-methylhistidine residue in rabbit skeletal muscle myosin (1971)
    s.l. : American Chemical Society
    Biochemistry 10 (1971), S. 229-236 
    Details
    ISSN: 1520-4995
    Quelle: ACS Legacy Archives
    Thema: Biologie , Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1021/bi00778a006
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  • 2
    Digitale Medien
    Digitale Medien
    Activities of Sperm Creatine Kinase and Dynein ATPase in Oligospermic Men (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 513 (1987), S. 0 
    Details
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1749-6632.1987.tb25120.x
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  • 3
    Digitale Medien
    Digitale Medien
    ε-N-Methyl Lysine in Myosin (1969)
    [s.l.] : Nature Publishing Group
    Nature 223 (1969), S. 834-835 
    Details
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The column dimensions were 0-9 x 40 cm, and it was packed with 'Phoenix JOT860-0' resin. The temperature of the column was 50-3, the buffer 0-35 M citrate at pH 5-36, and the flow rate 80 ml./h. In these conditions the neutral and acidic amino-acids were off by 30 min, while tyrosine appeared at 36 ...
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1038/223834a0
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  • 4
    Digitale Medien
    Digitale Medien
    Sperm Creatine Kinase Activity in Normospermic and Oligozospermic Hungarian Men (1999)
    Springer
    Journal of assisted reproduction and genetics 16 (1999), S. 35-40 
    Details
    ISSN: 1573-7330
    Schlagwort(e): creatine kinase ; male fertility ; unexplained ; maturity ; biochemical markers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Purpose: Our purpose was to measure sperm creatine phosphokinase (CK) activity, which reflects cytoplasmic retention in immature spermatozoa, in normospermic and oligozospermic Hungarian men. Methods: A study of 109 randomly selected men in a university-based andrology laboratory was done. Results: CK activity differed between normospermic and oligozospermic men (0.21 ± 0.02 vs. 1.19 ± 0.15 CK IU/10 8 sperm; n = 56 and n = 53; mean ± standard error of the mean, respectively). There was an inverse correlation between sperm concentration and CK activity (r = −0.70; n = 109). However, 28% of men in the range with less than 10 million sperm/ml had normal sperm CK activity (below the mean + 2 standard deviations of the group with greater than 30 × 10 6 sperm/ml), whereas 36% of men in the group with 20–30 million sperm/ml and 5% in the group with greater than 30 million sperm/ml had elevated CK activities, indicating that the incidence of mature and immature spermatozoa in specimens is independent from the sperm concentrations. Conclusions: The improved facility of sperm CK activity measurements, compared with sperm concentrations, in the assessment of sperm maturity was confirmed in a Hungarian population. The CK measurements aid the selection of the most efficient treatment for couples with male-factor or unexplained infertility, particularly when considering the options of intrauterine insemination, varicocelectomy followed by a waiting period, or ovulation workup/induction in wives of men who are oligozospermic but may have fertile sperm.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022545612784
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  • 5
    Digitale Medien
    Digitale Medien
    Optimal Utilization of Cryopreserved Human Semen for Assisted Reproduction: Recovery and Maintenance of Sperm Motility and Viability (1998)
    Springer
    Journal of assisted reproduction and genetics 15 (1998), S. 504-512 
    Details
    ISSN: 1573-7330
    Schlagwort(e): sperm cryopreservation ; viability ; motility ; banking ; freeze/thaw cycles
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Purpose: Our purpose was to evaluate sperm motility and viability and the maintenance of these parameters in already cryopreserved semen samples following repeated freezing/thawing cycles. Methods: Human spermatozoa were subjected to five cycles of cryopreservation/thawing. Recovery of sperm motility and viability and the proportion of viable nonmotile sperm were determined up to 6 hr after thaw. Results: Sperm motilities (prefreeze motility, 70.1%; n = 9 samples) after each of five freeze/thaw cycles were 24.4, 8.0, 3.5, 1.5, and 1.8%. The recovery of sperm viability was higher than that of motility after each cycle: 39.1, 25.3, 22.6, 17.8, and 16.5%. Recoveries of motility and viability were improved if the thawed samples were left in the original cryopreservation medium prior to refreezing vs. if a washing/resuspension step was included. The recovery of sperm motility in the first thawing cycle was indicative of the expected motile sperm recovery in the second thawing cycle. Conclusions: Cryopreserved semen that is intended to be reused in future assisted reproduction treatments should be thawed only once and aliquoted in the original freezing medium before refreezing. The recovery of sperm motility and viability in the second thawing cycle, thus the applicability of the sample in conventional in vitro fertilization or intracytoplasmic sperm injection may be anticipated in 〉90% of the samples. In view of intracytoplasmic sperm injection it is important that sperm viability is maintained better than motility; after the first, second, and third thawing cycles the ratios of motile:nonmotile viable sperm were 1:1, 1:4, and 1:7, respectively.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1022586505089
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  • 6
    Digitale Medien
    Digitale Medien
    Spermatogenesis-related change in the synthesis of the creatine kinase B-type and M-type isoforms in human spermatozoa (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 25 (1990), S. 258-262 
    Details
    ISSN: 1040-452X
    Schlagwort(e): Sperm creatine kinase ; Sperm CK activity ; Cellular maturity ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: We have demonstrated earlier that the per sperm creatine-N-phosphotransferase (CK) activity was increased in oligospermic vs. normospermic men. The increased sperm CK activity is related to higher concentrations of cellular CK, which may indicate a defect of cytoplasmic extrusion during spermatogenesis. In the present work, we examined whether in spermatozoa, similar to muscle, there is a change in the synthesis of B-CK and M-CK isoforms during cellular differentation. In 109 normospermic and 50 oligospermic specimens (sperm concentrations 60.6 ± 3.7 vs. 8.8 ± 1.3 million sperm/ml; all values expressed as mean ± SEM), the relative concentrations of the M-CK isoform (M-CK / M-CK+B-CK) were 27.2% ± 2.1% vs. 6.7% ± 0.9% (P 〈 0.001). The per sperm CK activities showed comparable differences (0.21 ± 0.02 vs. 0.89 ± 0.1 CK IU/100 million sperm; P 〈 0.001) in the two groups, and there was a close correlation between per sperm CK activities and M-CK concentrations (R = 0.69, P 〈 0.001, N = 159). This indicates that the loss of cytoplasm and the commencement of M-CK isoform synthesis are related events during the last phase of spermatogenesis, also that the incidence of spermatozoa with incomplete cellular maturation is higher in oligospermic specimens. In characterizing the M-CK, we found that sperm (unlike muscle tissue) lack the MB hybrid of CK dimers. However, in the presence of muscle M-CK, the muscle-sperm MB-CK hybrid has formed. Thus in sperm and muscle the M-CK isoforms are structurally different, whereas the B-CKs are apparently homologous. We suggest that the relative concentrations of sperm M-CK isoform is a biochemical marker of cellular differentiation that may also predict the functional intetrity, such as fertilization potential, of spermatozoa.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/mrd.1080250307
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  • 7
    Digitale Medien
    Digitale Medien
    Incomplete development of human spermatozoa is associated with increased creatine phosphokinase concentration and abnormal head morphology (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 34 (1993), S. 292-298 
    Details
    ISSN: 1040-452X
    Schlagwort(e): CK activity ; CK concentration ; CK immunocytochemistry ; Sperm morphometry ; Failed spermatogenesis ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: Our previous creatine phosphokinase (CK) activity studies in human sperm revealed differences among men and among sperm populations within the same specimen. Samples with low sperm concentrations, high incidence of abnormal sperm morphology, and diminished fertility had higher per sperm CK activity. In the present work, we demonstrated, with 14C-FDNB covalent CK active site modification and with direct CK immunocytochemistry, that the higher CK activity is related to an increased content of CK and of other proteins in sperm. Also, sperm heads with higher CK content were significantly larger and rounder and showed a higher incidence of amorph configuration. We suggest that these biochemical and morphological irregularities are related and are due to a failure of spermatogenesis, more specifically, to a higher retention of cytoplasm, which in normal sperm development is lost to the Sertoli cells as residual bodies. Thus higher CK activity and larger or irregular head size in human sperm signify cellular immaturity and a failure to complete spermatogenesis. © 1993 Wiley-Liss, Inc.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/mrd.1080340309
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  • 8
    Digitale Medien
    Digitale Medien
    Correlation between sperm creatine phosphokinase activity and sperm concentrations in normospermic and oligospermic men (1988)
    New York, NY : Wiley-Blackwell
    Gamete Research 19 (1988), S. 67-75 
    Details
    ISSN: 0148-7280
    Schlagwort(e): sperm CPK ; oligospermic/normospermic men ; sperm quality ; biochemical marker ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie
    Notizen: Toward the development of biochemical probes for the assessment of sperm function we have measured the activities of sperm creatine-N-phosphotransferase (CPK). There was a highly significant inverse correlation (P 〈 0.001 in all comparisons) between sperm CPK activities and sperm concentrations in specimens of normospermic and oligospermic men with 〉 30 million sperm/ml (0.106 ± 0.01 SEM, Nequals;90, expressed as CPK U/100 million sperm), 20-30 million sperm/ml (0.333 ± 0.07 SEM, Nequals;30) and 10-20 million sperm/ml (0.583 ± 0.12 SEM, Nequals;30) when compared with the CPK values of the 〈 10 million/ml specimens (2.242 ± 0.46 SEM, Nequals;30). Furthermore, the distribution of CPK activities within these four groups showed that 96%, 67%, 43%, and 4% of the samples, respectively, were in the 〈 0.250 CPK U/100 million sperm normal range (mean + 2 SD of the 〉 30 million sperm/ml group). However, there was no relationship between sperm CPK activities and the values of sperm motility (P 〉 0.15) or morphology (Pequals;0.38) in the samples. The migrated sperm fractions (significantly improved in motility and velocity parameters) showed CPK activities lower than the initial semen specimens (P 〈 0.01, Nequals;150). In fact, in some oligospermic men the CPK activities of the migrated sperm fractions were within the range of normospermic samples. The data suggest that sperm CPK values in the initial specimens and the degree of improvement in the migrated sperm fractions reflect the relative concentrations of a “normal” sperm subpopulation. We propose that CPK activities and similar objective biochemical parameters may be important in predicting sperm quality and the fertilizing potential of oligospermic men.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/mrd.1120190107
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