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  • 1
    Electronic Resource
    Electronic Resource
    Lysosomal hydrolases in reproductive organs during estrous cycle of the hamster (1984)
    New York, NY : Wiley-Blackwell
    Gamete Research 10 (1984), S. 57-66 
    Details
    ISSN: 0148-7280
    Keywords: Lysosomal hydrolases ; uterus ; ovary ; oviduct hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Changes in the total protein content and the activities of lysosomal hydrolases (arylsulfatase, acid phosphatases, β-glucuronidase, β-N-acetylhexosaminidase, α-L-fucosidase, and β-galactosidase) of the hamster genital tract during the 4 days of estrous cycle and in hormonally superovulated hamsters were measured. Levels of lysosomal hydrolases in uteri and uterine fluid changed significantly during the cycle. Similar changes were observed in uterine wet weight and uterine proteins. The pattern of enzyme activities in both the ovary and the oviduct were different from those in uteri. In the ovary, most enzyme activities and the total protein concentration remained elevated after ovulation. Protein concentration and enzyme activities were significantly higher in the ovary, oviduct, and uteri of superovulated hamsters as compared to controls.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120100107
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  • 2
    Electronic Resource
    Electronic Resource
    Enhancement of the acrosome reaction of hamster spermatozoa by the proteolytic enzymes, kallikrein, trypsin, and chymotrypsin (1985)
    New York, NY : Wiley-Blackwell
    Gamete Research 11 (1985), S. 19-28 
    Details
    ISSN: 0148-7280
    Keywords: spermatozoa ; acrosome reaction ; proteolytic enzyme ; hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The involvement of a kallikrein-kinin system in the motility of mammalian spermatozoa has been suggested by several investigators. We found that incorporation of kallikrein (0.1-1.0) unit/ml) in the sperm incubation medium did not enhance the motility of hamster spermatozoa that were already active. However, this enzyme significantly increased the incidence of the acrosome reaction. Trypsin (1.8-18 units/ml) and chymotrypsin (0.34-3.4 units/ml) also increased the incidence of the acrosome reaction, and accelerated its onset. Kinins (bradykinin and kallidin) added to the medium in a wide concentration range (1 ng/ml to 1 mg/ml) had no marked effects on either the motility or the acrosome reaction. A kallikrein-kinin system is apparently not of primary importance at least for the acrosome reaction. The enhancement of the acrosome reaction by exogenous proteinases may be due in part to accelerated removal or alteration of the sperm surface coat (glycoprotein) by the enzyme peior to the acrosome reaction. Exogenous proteinases may also act synergistically with endogenous (acrosomal) proteinases (and other enzymes) in altering membrane proteins and dispersing the acrosome matrix during the course of teh acrosome reaction.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120110103
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  • 3
    Electronic Resource
    Electronic Resource
    Partial purification and characterization of an alkaline proteinase from the rabbit testis (1985)
    New York, NY : Wiley-Blackwell
    Gamete Research 11 (1985), S. 69-82 
    Details
    ISSN: 0148-7280
    Keywords: Acrosin ; inhibitors ; alkaline ; proteinase ; acrosomal ; azocoll ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A proteolytic enzyme capable of cleaving intact proteins and synthetic substrates α-N-benzoyl-DL-arginine β-naphthylamide (Bz-Arg-NNap), α-N-benzoyl-L-arginine p-nitroanilde (Bz-Arg-NPhNO2), and α-N-benzoyl-L-arginine ethyl ester (Bz-Arg-OEt) was purified 92- fold from the rabbit testes. The enzyme exhibited optimal activity at pH 9.0 and 50°C. The polyacrylamide gel electrophoresis and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of the purified enzyme demonstrated multiple forms; the major band in the SDS-polyacrylamide gel electrophoresis corresponded to a Mt 48,000. The same value was established by the gel filtration over Sephadex G-75. The rabbit testicular alkaline proteinase (TAP) resembled acrosin in the hydrolysis of Bz-Arg-OEt. However, CaCl2, a potential stimulator of acrosin activity, inhibited the alkaline proteinase. The strong inhibitors of acrosin, eg pheny methyl sulphonyl fluoride (PMSF), tosyl lysine chloromethyl ketone (TLCK), and benzamidine did not inhibit the alkaline proteinase. TAP was activated by an acrosin inhibitor isolated from the rabbit testes. Since 0.5 M KCl was necessary for complete extraction of the enzyme and the bulk of the activity was present in 9,000g pellet of the testicular homogenate. The alkaline proteinase appeared to be associated with the membranous structures.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120110108
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  • 4
    Electronic Resource
    Electronic Resource
    Isolation of the inner acrosomal-nuclear membrane complex from rabbit spermatozoa (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 7 (1983), S. 215-226 
    Details
    ISSN: 0148-7280
    Keywords: sperm ; cytoplasmic droplet ; membrane ; acrosome ; nucleus ; decondensation ; rabbit ; Bio-Glas 2500 ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Rabbit spermatozoa were passed through a Bio-Glas 2500 (BG) column to yield pure cytoplasmic droplets and consequently the droplet-free spermatozoa. Rapid decondensation of sperm nuclei was achieved by 1 mM dithiothreitol (DTT) and 1.5 M NaCl. This treatment caused removal of the plasma and the outer acrosomal membranes. The viscosity of decondensed nuclei was reduced by pancreatic DNase. Further elution of the suspension from BG column yielded a membrane complex. On the basis of electron microscopic observations and the enzyme analysis, these membranes appeared to be the inner acrosomal-nuclear membrane complex (IANC). The IANC was also prepared from isolated sperm head by DTT-NaCl and Dnasetreatment and low-speed centrifugation.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120070303
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  • 5
    Electronic Resource
    Electronic Resource
    A modified column for sperm isoelectric focusing (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 7 (1983), S. 325-329 
    Details
    ISSN: 0148-7280
    Keywords: isoelectric focusing apparatus ; sperm ; protein ; density gradient ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A modified U-shaped column is described for efficient isoelectric focusing of spermatozoa, other cells, and protein. The washed spermatozoa of the rabbit showed a PI of 4.4. After sonication, heads and tails focused at same pH, indicating similar and equal charge.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120070404
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  • 6
    Electronic Resource
    Electronic Resource
    Phosphatidylcholine and phosphatidylinositol-specific phospholipases C of bull and rabbit spermatozoa (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 33 (1992), S. 281-286 
    Details
    ISSN: 1040-452X
    Keywords: Sperm (bull, rabbit) ; Plasma membranes ; Acrosomal membranes ; Phosphatidylinositol specific phospholipase C ; Phosphatidyl choline specific phospholipase C ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Acrosomal reaction is an essential prerequisite to fertilization. The changes in lipid composition of sperm membranes cause fusion of the plasma and outer acrosomal membranes that results in the exocytosis of acrosomal contents. We report that both bull and rabbit spermatozoa contain a phosphatidylcholine-specific phospholipase C (PC-PLC) that hydrolyzes L-α-dipalmitoyl-(choline-methyl-14C-153.0 Ci/mmol and a phosphatidyl-inositol-specific phospholipase C (Pl-PLC)) that hydrolyzes L-α-(Myo)-lnositol-2-3H (N)-5.2 Ci mmol. Pl-PLC from bull sperm acrosome has been purified 568 × fold with a specific activity 6.25 ± 0.6 nmol/min/mg protein, km 0.004 mM, and Vmax 12 nmol/min/mg protein. Both enzymes had optimum at pH 7.5. The activity of PC-PLC remained unaffected by varying concentrations of Ca2+, whereas Pl-PLC activity was significantly increased. The bulk of Pl-PLC was found to be associated with inner acrosomal membrane of bull and rabbit sperm, while PC-PLC was found in the outer acrosomal membranes in the bull sperm and the plasma membrane of the rabbit sperm. Both enzymes are compartmentalized in sperm cell. © 1992 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080330308
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  • 7
    Electronic Resource
    Electronic Resource
    Phospholipids of rabbit and bull sperm membranes: Structural order parameter and steady-state fluorescence anistropy of membranes and membrane leaflets (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 35 (1993), S. 209-217 
    Details
    ISSN: 1040-452X
    Keywords: Sperm (bull, rabbit) ; Plasma membranes ; Acrosomal membranes ; Phospholipids ; Membrane fluidity ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The plasma (PM), outer acrosomal (OAM), and inner acrosomal membranes (IAM) were isolated from rabbit and bull spermatozoa and the major phospholipids characterized. Choline-containing phospholipids, phosphatidylcholine (PC) and sphingomyelin (SM), constituted more than 60% of the total phospholipids (TPL) in all membranes of both species. Approximately more than 50% of PC in membrane preparations contained some form of ether linkage. Compared to OAM and IAM, cholesterol to phospholipid molar ratio was highest in PM of both species. Contrarily, protein to phospholipid ratio for PM was lowest compared to other membranes. The sphingomyelin to phosphatidylcholine ratio increased in the direction from PM to OAM to IAM. The hydrophobic fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH) was used to examine both the steady-state fluorescence anisotropy parameters and structural order parameter SDPH. The data showed higher rigidity in rabbit spermatozoa compared to bull spermatozoa (SDPH = 0.7582 and SDPH = 0.7326). In both species OAM had higher rigidity compared to the other two membranes (SDPH(OAM) = 0.7809, SDPH(PM) = 0.7308, and SDPH(IAM) = 0.7481 for bull; SDPH(OAM) = 0.8091, SDPH(PM)= 0.7857, and SDPH(IAM) = 0.7663 for rabbit). The inner leaflets of bull and rabbit spermatozoal membranes had significantly higher rigidity than the outer leaflets (for inner leaflet: rabbit-SDPH(PM) = 0.8391, SDPH(OAM) = 0.8149, and SDPH(IAM) = 0.7675; bull-SDPH(PM) = 0.8000, SDPH(OAM) = 0.7990, and SDPH(IAM) = 0.7990, and for outer leaflet: rabbit-SDPH(PM) = 0.7021, SDPH(OAM) = 0.7145, and SDPH(IAM) = 0.6867; bull-SDPH(PM) = 0.6986, SDPH(OAM) = 0.5980, and SDPH(IAM) = 0.7388). © 1993 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080350215
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  • 8
    Electronic Resource
    Electronic Resource
    Purification and characterization of β-glucuronidase from bull seminal plasma and its role in fertilization (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 38 (1994), S. 404-409 
    Details
    ISSN: 1040-452X
    Keywords: β-glucuronidase ; Seminal plasma ; Ovum ; Cumulus ; Fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Bull seminal plasma contains high levels of β-glucuronidase. The present study describes the isolation and characterization of β-glucuronidase, and its role in fertilization. β-glucuronidase was purified by ion exchange chromatography, saccharolactone-agarose affinity chromatography, and gel filtration. The specific activity of the purified enzyme was 4,414 μmoles/mg protein/min. The purified enzyme showed a single band on 7.5% PAGE. On SDS-PAGE, the enzyme appeared to consist of four identical subunits of Mr 75,000 each. The apparent Km and Vmax for β-glucuronidase were 0.4 mM and 5.7 μmol/min using phenolpthalein mono-β-glucuronic acid as the substrate. β-glucuronidase appeared to accelerate the cumulus dispersion in vitro. © 1994 Wiley-Liss, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080380408
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  • 9
    Electronic Resource
    Electronic Resource
    Identification of a cellular protein that binds to tat-responsive element of TGFβ-1 promoter in glial cells (1997)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 67 (1997), S. 466-477 
    Details
    ISSN: 0730-2312
    Keywords: Tat ; TAR ; HIV-1 ; TGFβ-1 promoter ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Tat is a transcriptional transactivator produced by the human immunodeficiency virus type 1 (HIV-1) and plays a pivotal role in enhancing expression of the viral genome in the infected cells. Although initial studies have suggested that interaction of Tat with the transactivation responsive element (TAR), located within the LTR, is essential for Tat function, subsequent studies indicated that Tat has the ability to augment transcription of viral and cellular genes by a TAR-independent mechanism. In early studies we demonstrated that HIV-1 Tat stimulates transcription of the transforming growth factor, TGFβ-1, gene in glial cells. In this study, we have identified a cellular protein that interacts with the Tat-responsive region located between nucleotides -323 to -453 of the regulatory sequence of the TGFβ-1 promoter. Results from footprinting analysis revealed association of cellular proteins with the 130 nucleotide sequence located in the Tat-responsive region. Analysis of the associated protein by UV-crosslinking suggested the involvement of a protein between 40-45 kDa in size which preferentially interacts with the GC/GA rich sequence of the TGFβ-1 Tat-responsive sequence in a single-stranded configuration. The ability of the previously identified 40 kDa protein, named Pur α to bind to the GC/GA sequence in the single-stranded configuration, similar to those from TGFβ-1 promoter prompted us to investigate its binding capacity to the TGFβ-1 sequence and its transcriptional activity on the TGFβ-1 promoter. Results from band shift studies indicated the association of the bacterially produced Pur α to the TGFβ-1 DNA sequences positioned within the Tat-responsive region. Overexpression of Pur α in glial cells constitutively producing Tat augmented transcription of the TGFβ-1 gene. These results are consistent with previous reports on the cooperative action of Pur α and Tat in modulating other eukaryotic promoters. The importance of these findings with regard to deregulation of other cellular genes by HIV-1 Tat is discussed. J. Cell. Biochem. 67:466-477, 1997. © 1997 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    The role of the G1 period in the life cycle of eukaryotic cells (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 119 (1984), S. 77-81 
    Details
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The objective of this study was to test the concept that the G1 period lacks any specific function in the life cycle of mammalian cells and hence could be drastically reduced without any effect on the generation time. HeLa cells were grown in medium containing an optimum dose (60 μM) of hydroxyurea at which the duration of S period was prolonged with little or no increase in generation time. At this concentration of hydroxyurea, we observed a maximum of 3 h (or 28.5%) reduction in the G1 period. We also studied the effects of synchronization in S phase by single and double thymidine blocks on cell size and its relationship to the duration of G1 in the subsequent cycle. By these treatments, we could reduce the G1 period by not more than 2 to 3 h. The reduction in G1 period was not directly proportional to the size (volume) of the G1 cells. These results suggest that G1 period has certain specific functions and cannot be eliminated by alterations in culture conditions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcp.1041190113
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