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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 513 (1987), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 17 (1987), S. 115-129 
    ISSN: 0148-7280
    Keywords: spermiogenesis ; actin ; perinuclear material ; postacrosomal region ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The sperm head of the plains mouse, Pseudomys australis, has three curved hooks projecting from its anterior margin. The two ventral hooks have previously been shown to consist largely of an extension of the subacrosomal material. To characterize further the structure and composition of the ventral hooks, we have examined their formation during spermiogenesis using transmission electron microscopy, silver staining, and actin localization with NBD-phallacidin. The ventral hooks develop as an extension of the perinuclear space and postacrosomal dense lamina on the anteroventral margin of the sperm head. Bundles of 6-nm-thick filaments appear in the core of each hook; these are probably actin filaments based on staining of the hooks with NBD-phallacidin. Just prior to spermiation, electron-dense material condenses in the core of the ventral hooks and concurrently in the perinuclear space in the remainder of the sperm head. The two ventral hooks thus appear to consist of a core of perinuclear material and actin filaments, which is enclosed by a continuation of the postacrosomal dense lamina.
    Additional Material: 23 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 231-244 
    ISSN: 0148-7280
    Keywords: plains mouse ; sperm head ; hooks ; ultrastructure ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The ultrastructure of the sperm head of the plains mouse, Pseudomys australis, and the effects of chemical treatments on the sperm head components has been investigated to determine the nature of the material in the hooks on the apical margine of the sperm head. Ultrastructural studies indicated that the dorsal hook contained nuclear, subacrosomal, and acrosomal material, whereas the two ventral hooks were largely composed of an extention of the subacrosomal material with two thin acrosomal projections at their base. Acrosomal material was dispersed by mild detergent treatment, where as the bulk of the material in the ventral hooks were generally found to be similar to the subacrosomal material in the dorsal hook in their resistance to the various chemical treatments. Treatment of sperm with NaOH or guanidine-hydrochloride and DTT revealed two layers of material in the ventral hooks.
    Additional Material: 24 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 33 (1992), S. 189-194 
    ISSN: 1040-452X
    Keywords: Spermatozoa ; Diploid ; Disomy ; Fluorescence in situ hybridization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Fluorescence in situ hybridization (FISH) with DNA probes specific to chromosomes 17 and the X has been applied to human ejaculated sperm. After sperm nuclei were decondensed with EDTA and DTT, biotinylated alpha satellite DNA probes TR17 and TRX were separately used on preparations from thirteen healthy donors. After hybridization 96% of sperm were labelled with the TR17 probe and 48% of sperm were labelled with the TRX probe. Frequencies of 0.33% disomic 17 and 0.29% disomic X sperm were found. The frequencies of diploid sperm were assessed as 0.37% using the TR17 probe and 0.20% using the TRX probe which labelled only one half of the sperm; after correcting the result from the X-probe to 0.40% the two frequencies are very similar. © 1992 Wiley-Liss, Inc.
    Additional Material: 10 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 35 (1993), S. 285-292 
    ISSN: 1040-452X
    Keywords: Oocyte ; Mouse ; Surface labelling ; Proteins ; Biotinylation ; Chemiluminescence ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In this study, we have labelled proteins on the surface of unfertilized, zona-free mouse oocytes using a nonisotopic biotinylation procedure. The zona pellucida was weakened by brief incubation in chymotrypsin and removed by mechanical pipetting through a narrow-bore glass pipette. Surface proteins were labelled using sulfo-NHS-biotin (sulfosuccinimidobiotin), a water-soluble, membrane-impermeable biotinylation reagent. The distribution of biotinylated proteins on the oocyte surface was assessed by fluorescence microscopy using streptavidin-FITC. Bright fluorescence was noted on the surface of the oocyte, except in a circular region overlying the meiotic spindle where the fluorescence was weak or absent. The intensity of fluorescence was markedly reduced by incubation of biotinylated oocytes in trypsin (1 mg/ml) or chymotrypsin (2 mg/ml), and in vitro fertilization experiments showed that biotinylation did not compromise the fertilizability of the oocytes. The biotinylated proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and analyzed by Western blotting using streptavidin-HRP and enhanced chemiluminescence (ECL) detection. The most prominent biotinylated proteins were of Mr 82 and 69 kD, but other major proteins of Mr 93, 78, 61, 52, 49, 40, 28, and 22 kD were detected, as well as 14 minor proteins of Mr 18-100 kD. The major bands could be detected in fewer than 50 oocytes. This biotinylation procedure is fast, versatile and sensitive, and it is therefore an excellent tool for studying proteins exposed on the surface of mammalian oocytes and embryos. © 1993 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 34 (1993), S. 308-313 
    ISSN: 1040-452X
    Keywords: Sex chromosomes ; Human sperm ; Haploid ; Diploid ; Double fluorescence in situ hybridization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Double fluorescence in situ hybridization (FISH) was used to detect sex chromosomes in decondensed human sperm nuclei. Biotinylated X chromosome specific (TRX) and digoxigenin-labeled Y chromosome specific (HRY) probes were simultaneously hybridized to sperm preparations from 12 normal healthy donors. After the hybridization, the probes were detected immuno-cytochemically, using two different and independent affinity systems. Ninety-six percent of the 12,636 sperm showed fluorescent labeling, of which 47.4% were haploid X and 46.8% were haploid Y. A frequency of 0.46% of XX-bearing sperm (0.28% disomic, 0.18% diploid) and 0.38% YY-bearing sperm (0.21% disomic, 0.17% diploid) was found. The overall proportions of X- and Y-bearing sperm in the ejaculates were 47.9% and 47.2%, respectively, which was not significantly different from the expected 50:50 ratio. In addition 0.21% of cells appeared to be haploid XY-bearing sperm, 0.62% were diploid XY-bearing cells, and 0.05% of cells were considered to be tetraploid cells. The application of double FISH to human sperm using X-chro-mosome and Y-chromosome probes has allowed a more accurate assessment of the sex chromosal complements in sperm than single FISH method and quinacrine staining for Y-bodies. © 1993 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 23 (1989), S. 279-287 
    ISSN: 0148-7280
    Keywords: oocyte ; sperm head ; zona pellucida ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The sperm head of many Australian hydromyine rodents has three curved hooks projecting from its anterior margin; the structure of the hooks has been characterized, but their function is unknown. In this study, we have investigated whether the hooks might have evolved to assist sperm penetration through more formidable egg vestments, particularly the zona pellucida. Cumulus-oocyte complexes were obtained from two species that possess a three-hooked sperm head (Pseudomys australis and P. nanus) and one species that does not (Notomys alexis) and examined by light and electron microscopy. After fixation in the presence of ruthenium red, the zona pellucida was found to consist of a fibrillar meshwork, but there were no interspecific structural differences. A corona radiata was absent, and the cumulus extracellular matrix was composed of filaments and electron-dense granules in each species. Measurements of the zona thickness in freshly ovulated, unfixed oocytes revealed that it was thinnest (7.8 μm) in P. australis. Which has a three-hooked sperm head, and thickest (11.4 μm) in N. alexis, the species in which the ventral hooks are absent. Hence, no correlation was found between the thickness of the zona pellucida or the structure of the cumulus-oocyte complex, and the presence of three hooks on the sperm head. We conclude, therefore, that it is unlikely that the evolution of the three-hooked sperm head is an adaptation for penetration of increased barriers around the oocyte.
    Additional Material: 11 Ill.
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  • 8
    Publication Date: 1993-03-01
    Print ISSN: 0012-1606
    Electronic ISSN: 1095-564X
    Topics: Biology
    Published by Elsevier
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