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  • Articles  (16)
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  • Wiley-Blackwell  (16)
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  • American Chemical Society
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  • 1990-1994  (1)
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  • 1
    Electronic Resource
    Electronic Resource
    Actin-mediated surface motility during sea urchin fertilization (1983)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 3 (1983), S. 513-524 
    Details
    ISSN: 0886-1544
    Keywords: fertilization ; actin ; microfilaments ; sea urchin ; cell division ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The sea urchin egg at fertilization is an ideal model in which to study actin-mediated surface activity. Electron microscopy of unfertilized eggs demonstrates the presence of thousands of well-arrayed short microvilli, which appear supported by cytochalasin-sensitive actin oligomers as detected with rhodamine-labeled phalloidin staining of permeabilized eggs. At insemination, the previously short microvilli elongate and cluster around the successful sperm during incorporation. Phalloidin staining demonstrates a tremendous recruitement of polymerized actin into the site of sperm incorporation, resulting in the formation of the fertilization cone. Fertilization of cytochalasin-treated eggs results in the normal activation of the metabolic and bioeletric events, but sperm incorporation does not occur since the localized actin assembly required for fertilization cone formation is precluded. After sperm incorporation, the entire fertilized surface is restructured, as a result of a massive polymerization of actin to produce a burst in microvillar elongation. Addition of cytochalasin to eggs immediately following sperm incorporation demonstrates the recruitment of actin assembly for the proper progression through the first cell cycle. During normal cell divison, the egg surface retains the long microvilli. The furrow which forms at cytokinesis does not appear as a unique new structure, but rather as a reorganization of the cortical microfilaments. Quantitative fluorescence microscopy argues against an increase in microfilaments during early cytokinesis. At the latest stages of cytokinesis, a thickening of the cortical actin is noted, which could possibly be interpreted as a contractile ring. A minor basal level of actin assembly with numerous nucleation sites in unfertilized eggs and a tremendous but localized assembly of microfilaments surrounding the sperm during incorporation, followed by a massive global microfilament assembly event to elongate the fertilized egg microvilli resulting later in the reorganization of these microfilaments to produce the forces necessary for cytokinesis, highlight the utility of the study of sea urchin eggs at fertilization for understanding actin-membrane interactions.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970030518
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  • 2
    Electronic Resource
    Electronic Resource
    Redistribution of actin and fascin in sea urchin eggs after fertilization (1980)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 1 (1980), S. 31-40 
    Details
    ISSN: 0886-1544
    Keywords: actin ; fascin ; actin cross-linking proteins ; fertilization ; microvilli ; sea urchin eggs ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Following fertilization, the sea urchin egg cortex undergoes a structural change involving the assembly and organization of actin filaments into microvilli. Antifascin localizes this actin cross-linking protein in the microvilli of the fertilized egg cortex but no organized staining is present in the unfertilized cortex. Determination of the actin content of eggs using the DNAase I inhibition assay indicates that actin is about 1.4% of the total protein. Approximately 90% of this actin is soluble in low calcium isotonic extracts of unfertilized eggs while only 60-65% can be recovered in identical extracts of fertilized eggs. Similar measurements for fascin using a radioimmunoassay indicate this molecule represents about 0.3% of the total egg protein, essentially all of which is recovered in low calcium isotonic extracts of unfertilized eggs. After fertilization only 65-70% of this actin cross-linking protein is in the soluble phase. These results demonstrate a markedly different solubility for actin and fascin after fertilization, when the indirect immunofluorescence staining localizes fascin in the microvilli, and are consistent with the idea that fascin organizes newly polymerized actin filaments into the microvillar cores. A consideration of the amounts of actin and fascin incorporated into the cortex after fertilization and the number of microvilli on the egg surface indicates that the measured values are sufficient to account for the observed microvillar elongation.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970010104
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  • 3
    Electronic Resource
    Electronic Resource
    A 70 kD microtubule-binding protein from starfish eggs: Purification, characterization, and localization during meiosis and mitosis (1990)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 15 (1990), S. 168-180 
    Details
    ISSN: 0886-1544
    Keywords: microtubule-associated proteins (MAPs) ; taxol ; oocyte maturation ; fertilization ; cell division ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A microtubule-binding protein was purified from eggs of the starfish, Asterias amurensis, through several steps of purification including the taxol-dependent procedure [Vallee, 1982, J. Cell Biol. 92:435-442]. This protein consists of a single polypeptide chain having an apparent molecular mass of 70 kD determined by SDS-PAGE. The 70 kD protein was identified as a unique microtubulebinding protein, judging from electrophoretic mobility, cleavage pattern by limited proteolysis, heat stability, and immunocrossreactivity. The 70 kD protein binds to brain and egg microtubules. It does not promote assembly of brain tubulin, but promotes that of egg tubulin in vitro in a concentration-dependent manner.Using indirect immunofluorescence and immunoelectron microscopy with the anti-70 kD protein antibody, we analyzed the cellular localization of the 70 kD protein in starfish oocytes and eggs during both meiotic maturation (meicsis) and first cleavage (mitosis). Immunofluorescence studies showed that the 70 kD protein localized on microtubule structures spread widely throughout the cytoplasm, the sperm aster, and the microtubules making up the mitotic apparatus through both meiosis and mitosis. The antibody, however, did not recognize sperm axonemes. These results were confirmed by immunoelectron microscopy. Using a colloidal gold technique, the 70 kD protein was localized along the microtubules in vivo.This 70 kD protein is the first microtubule-binding protein that has been shown to localize along the microtubules in oocytes and eggs throughout meiosis and mitosis and to promote microtubule assembly. The 70 kD protein may be involved in the dynamic changes of microtubule structures occurring within oocytes and eggs.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970150306
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  • 4
    Electronic Resource
    Electronic Resource
    Microtubule-containing detergent-extracted cytoskeletons in sea urchin eggs from fertilization through cell division: Antitubulin immunofluorescence microscopy (1983)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 3 (1983), S. 213-226 
    Details
    ISSN: 0886-1544
    Keywords: microtubules ; fertilization ; cell division ; sea urchin ; cytoskeleton ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The microtubule-containing structures that appear in eggs during fertilization and cell division in the sea urchins Lytechinus variegatus and Arbacia punctulata were detected by antitubulin immunofluorescence microscopy of detergent extracted cytoskeletal preparations. The extraction buffer, which is composed of 0.55 mM MgCl2, 10 mM EGTA, 25 mM MES, 25% glycerol, 1% Nonidet P-40, and 25 μM PMSF, pH 6.7, allows for dramatically improved fluorescent images compared to those obtained using conventional staining procedures, with residual background staining being reduced to near zero.The immunofluorescent images obtained using this technique provide information on several motile events that occur during the first cell cycle. This technique demonstrates that all of the cytoplasmic microtubules are associated with the incorporated sperm's centrioles during female pronuclear migration. This changes during the centration of the male and female pronuclei at which time a monastral array of microtubules forms in the egg's cytoplasm. A large proportion of the monastral microtubules do not appear to be associated with the centrioles. At prophase and early metaphase, the centrioles are the dominant microtubule organizing centers (MTOCs) consistent with mitotic theories that the kinetochore catches, but does not initiate, microtubules. Observations of intercentriolar distances show that there are three stages of pole separation during the first cell cycle. The initial separation occurs during pronuclear centration, the second during the streak stage, and the final one during the late stages of mitosis. At telophase, polar microtubules appear to extend into the cortex supporting the cell surface at all regions except the presumptive cleavage site.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970030303
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  • 5
    Electronic Resource
    Electronic Resource
    Radioiodination studies of the envelopes from Xenopus laevis eggs (1983)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 22 (1983), S. 235-244 
    Details
    ISSN: 0730-2312
    Keywords: fertilization ; egg envelopes ; glycoproteins ; molecular topography ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: To investigate the molecular basis of the observed morphological and biological characteristics of coelomic egg envelopes (CE), vitelline envelopes (VE), and fertilization envelopes (FE) of Xenopus laevis eggs, envelopes were radioiodinated under a variety of conditions: in situ, isolated and intact, or solubilized. The distribution of 125I in envelope components was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Each envelope type displayed unique profiles when iodinated in the intact state. A major constituent of VE, the 41,500 molecular weight component, was not labeled in the intact state, although the corresponding component of CE was heavily labeled. After dissociation of the envelope by guanidine-HCl or sodium dodecyl sulfate, all of the components could be radioiodinated. However, when the envelopes (VE and FE) were dissolved by heating and subsequently radioiodinated by lactoperoxidase, the resulting radioactivity profile was similar to that of the intact envelopes, suggesting that in the heat-dissolved envelope, the individual components retain similar structural relations as in the intact envelope. Quantitative but not qualitative differences were found between the inner and outer aspects of VE and FE. The significance of these findings is discussed in relation to what is known about the morphological, biological, and molecular properties of the envelopes.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240220405
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  • 6
    Electronic Resource
    Electronic Resource
    A new procedure for rapidly scoring acrosome reactions of human sperm (1980)
    New York, NY : Wiley-Blackwell
    Gamete Research 3 (1980), S. 211-216 
    Details
    ISSN: 0148-7280
    Keywords: acrosome ; human sperm ; lectin ; capacitation ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Because the acrosome of human sperm is too small to be directly visualized by phase-contrast microscopy, acrosome reactions (that is loss of the acrosome) are generally not evaluated in studies of human sperm capacitation and fertilization. Nevertheless, it would be useful in such studies to have a technique for easily identifying and quantitating acrosome-reacted sperm. In this paper, we describe a method for labeling the human sperm acrosome with fluorescein-conjugated Ricinus communis agglutinin-60 (FITC-RCA); we show that in sperm without acrosomal caps, FITC-RCA labeling occurs either not at all or only in the equatorial segment of the acrosome. To determine if the absence of FITC-RCA labeling in the acrosomal cap region gives a reliable estimate of acrosome reactions, washed sperm or sperm incubated in a capacitating medium (BWW) were divided into two groups, which were then fixed for FITC-RCA labeling or transmission electron microscopy. Counts of acrosome reactions made by each method were similar, and we observed an increase in the percentage of reactions following incubation in BWW. We conclude that the FITC-TCA labeling technique is a reliable method for accurately scoring the percentage of acrosome-reacted human sperm.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/mrd.1120030303
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  • 7
    Electronic Resource
    Electronic Resource
    Properties of the first and second factors released after hamster sperm make contact with the zona pellucida prior to fertilization in vitro (1980)
    New York, NY : Wiley-Blackwell
    Gamete Research 3 (1980), S. 395-403 
    Details
    ISSN: 0148-7280
    Keywords: sperm-zona contact ; fertilization ; peptides ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: An investigation was made as to the nature of two of the factors, termed S1, released within the first 30 minutes after contact is made between capacitated hamster sperm and the zona pellucida in vitro. Previous studies showed that these S1 factors were detected two and 20 to 25 minutes after the gametes were combined and that, based on filtration studies, the former possessed a molecular weight of less than 5,000 daltons. The present results show that the quantity of the 20-25-minute S1 factor released into the supernatant increased linearly as a function of the sperm concentration. This factor passed unimpeded through a filter with a 5,000 molecular weight cutoff but only 42% of the activity traversed a filter with a cutoff of 2,000 daltons. The two-minute S1 factor, in the virtual total absence of cells, was stable for 10 to 15 minutes, but lost significant activity upon longer incubation. Under the same conditions, the 20-25-minute factor lost approximately 25% of its activity within 15 minutes, but remained stable at this level for at least 45 minutes of incubation. Both S1 factors were not affected by a mixture of glycosidases, but were inactivated by subtilisin, trypsin, and leucine aminopeptidase which was contaminated with endopeptidases. The activity of the two-minute S1 factor appeared more susceptible to the action of the proteases than that of the 20-25-minute S1 factor. In contrast to previous results obtained with the two-minute S1 factor, the release of the 20-25-minute S1 factor was not inhibited by the inclusion of soybean trypsin inhibitor a t concentrations which are known to inhibit penetration of the zona by the sperm. The results suggest that the two- and 20-25-minute S1 factors are peptides which are not identical.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120030410
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  • 8
    Electronic Resource
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    Artificial fertilization of gametes from the South African clawed frog, Xenopus laevis (1980)
    New York, NY : Wiley-Blackwell
    Gamete Research 3 (1980), S. 45-57 
    Details
    ISSN: 0148-7280
    Keywords: clawed frog ; egg ; fertilization ; jelly coat ; motility ; sperm ; Xenopus laevis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A reproducible and effective method for fertilization eggs of Xenopus laevis was developed based of systematic manipulation of environmental factors. The effects of varying concentrations of individual components of a fertilization medium were tested by measuring jelly swelling, sperm motility, and sperm longevity. Results were used to develop an improved medium for fertilization, consisting of 41.25 mM NaCl, 1.25 mM KCl, 0.25 mM CaCl2, 0.0625 mM MgCl2, 0.5 mM Na2HPO4, 2.5 mM HEPES, 1.9 mM NaOH, final pH(2°) 7.8.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120030106
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  • 9
    Electronic Resource
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    Cytoplasmic and sperm nuclear transformations in fertilized ammonia-activated sea urchin (Arbacia punctulata) eggs (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 65-78 
    Details
    ISSN: 0148-7280
    Keywords: sea urchin ; ammonia-activation ; fertilization ; fertilization cone ; sperm asters ; pronuclear development ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Studies examining cytoplasmic and sperm nuclear transformations in sea urchin (Arbacia punctulata) eggs inseminated at different periods after ammonia activation have been caried out at the light- and electron-microscopic levels of observation. Arbaca eggs treated with ammonia-seawater demonstrated chromosome condensation after DNA synthesis and underwent a chromosome cycle similar to that described for Lytechinus [Mazia, 1947]. Cortical granule reaction, fertilization cone formation, and sperm aster development in eggs fertilized at 20 (interphase), 50 (prometaphase), and 180 (interphase) min after ammonia activation were structurally simialr to processes in untreated zygotes. Cyclical changes in the formation of fertilization cones and sperm asters, as reported for eggs fertilized after activation by agents that induce a cortical granule reaction, were not observed. Although sperm nuclear transformations were prolonged (14 vs 18 min), male pronuclei that developed in eggs fertilized 20 min after ammonia activation were morphologically similar to those observed in fertilized, untreated ova and incorporated 3H-thymidine. Sperm incorporated into eggs at 50 min after ammonia activation underwent nuclear envelope breakdown and chromatin despersion; however, 3H-thymidine incorporation was not observed, and male pronuclei rarely developed (less than 5% of all specimens examined). Subsequent to dispersion, the paternal chromatin condensed into chromosomes which were associated with an aster. These results demonstrate that although ammonia-activated eggs inseminated at interphase or prometaphase undergo similar cytoplasmic alterations, sperm nuclear transformations vary with the chromosome cycle of the egg.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120080108
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  • 10
    Electronic Resource
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    Gametes and fertilization in the Chinese hamster (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 97-117 
    Details
    ISSN: 0148-7280
    Keywords: egg ; soernatozoa ; fertilization ; Chinese hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Freshly ovulated eggs are each surrounded by a compact cumulus oophorus. The overall diameter of the normal egg (including the zona pellucida) is about 100 μm. Cumulus cells, particularly those near the egg, are arranged redially in a viscous noncellular matrix. The spermatozoon is about 250 μm in length. The head a large acrosome, changes in which can be readily examined with the light (phase- contrast) microsope. When exposed to physiological salt solutions, testicular spermatozoa either were motionless or flexed the posterior half of their tails slowly. Spermatozoa from the caput epididymis were highly motile, flexing the entire tail. A few of them moved progressively. Mature spermatozoa from the vas deferens were highly motile and moved either straightforward or in a circle. They vibrated their tails stiffly without flexing them.In normally mated females, fertilization began sometime between 2 and 3 h after ovulation and was completed within the next 4 to 5 h. Spermatozoa swimming in the ampullary fluid or within the cumulus oophorus about the time of fertilization flexed the anterior half (which roughly corresponds to the midpieac region) of their tails. This peculiar movement may be homologous to the so-called “hyperactivation” of spermatozoa as reported in several other mammalian species. Actively motile spermatozoa within the cumulus or no the zona pellucida had either modified (“collapsed”) or no acrosomal caps. The sperm head usually passed verticually or nearly through the zona, but the path was oblique in some instances. In 54% of the recently fertilized eggs examined, the entire length of the sperm tail was within the perivitelline space; in the other 46% of the eggs varying lenghts of the tail remined the perivitelline space, the tails were extruded from the vitellus of many eggs even before the eggs began their first cleavage.When unfertilized eggs in the cumulus oophorus were inseminated with vas deferens spermatozoa in a modified Tyrode's solution (m-TALP), about 80% of them were ferrtilized by 4-6 h after insemination. The vast majority were monospermic. When eggs were freed from the cumulus prior to insemination, none were fertilized, suggesting that the cumulus cells or their matrix assisted capacitation and/or the acrosome reaction of the spermatozoa under the in vitro conditions employed. No eggs were fertilized by the testicular or caput epididymal spermatozoa regardless of the presence or absence of cumulus oophorus around the eggs at the time of insemination.
    Additional Material: 25 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120080202
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  • 11
    Electronic Resource
    Electronic Resource
    Partial activation of sea-urchin eggs by bonellin (1980)
    New York, NY : Wiley-Blackwell
    Gamete Research 3 (1980), S. 309-316 
    Details
    ISSN: 0148-7280
    Keywords: fertilization ; membrane potential ; bonellin ; amino acid incorporation into proteins ; DNA synthesis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We here describe further studies on the action of bonellin on sea-urchin eggs. Bonellin brings about Some of the changes that are known to occur in the egg upon fertilization. In particular, it appears to cause the increased rate of incorporation of amino acids into proteins, the increase of the voltage noise, and the exocytosis of some of the cortical granules. A comparison with the effect of ammonia is discussed.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/mrd.1120030402
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  • 12
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    The effect of catecholamines and their antagonists on the fertilization of cumulus-free mouse ova in vitro at a suboptimal spermatozoal density (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 7 (1983), S. 111-122 
    Details
    ISSN: 0148-7280
    Keywords: catecholamines ; antagonists ; mouse ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A suboptimal sperm concentration was used to assess the capacity of catecholamines to stimulate the fertilization of cumulus free F1,(C57BL × CBA) mouse ova in vitro. At a concentration of 50 μM, (L) epinephrine significantly increased the proportion of ova fertilized at 2 × l05 spermatozoa/ml. However, when (D, L) propranolol at an equimolar concentration was tested for inhibition of the (L) epinephrine effect, fertilization was inhibited in both the test and control dishes. At l0μM, propanolol by itself or in the presence of 50μM (L) epinephrine significantly increased the number of ova fertilized at 2 × l05 sperm/ml. Norepinephrine (50 μM) and phentolamine (50 μM), either alone or together, were also slightly stimulatory. Some data are presented to suggest that propranolol may act in a nonadrenergic manner to precipitate the acrosome reaction and that the stimulatory effect is maximised when it is added to spermatozoa at the same time as ova addition. It was suggested that propranolol may act to trigger calcium influx by a nonspecific alteration in membrane function for example in (Ca + Mg) ATPase activity. It was concluded that spermatozoa at suboptimal densities are capable of achieving fertilization and that sperm concentration dependency in fertilization in vitro may be a reflection of the proportion of spermatozoa achieving capacitation.
    Additional Material: 5 Tab.
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    URL: http://dx.doi.org/10.1002/mrd.1120070203
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  • 13
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    Effects of egg aging on in vitro fertilization and first cleavage division in the hamster (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 219-230 
    Details
    ISSN: 0148-7280
    Keywords: egg aging ; fertilization ; cleavage anomalies ; hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The postovulatory fertile life of mammalian eggs is remarkably short (approximately 6-36h). Anomalies of embryogenesis may result from fertilization of aged, defective eggs. Attempts to study this problem using whole-animal models are complicated by chances in the natural milieu of the gametes. In the present study, postovulatory hamster eggs were allowed to agein vivo then fertilized in vitro. Cumulus-intact eggs recovered from superovulated hamsters either 2 or 9 h after the estiated time of ovulation (12 h postHCG) were incubated for 4 h with preincubated sperm suspentions in a modified Tyrode's solution devised for in vitro fertilization. Eggs were either fixed or cultured for another 20h in fresh medium to allow cleavage to occur, then examined by light microscopy (phase and interference-contrast). No significant difference was found in the ablities of fresh and aged eggs to be penetrated by spermatozoa (94% vs 90%, respectively; 8 replicated experiments), but only 59% of penetrated aged eggs were found to undergo morphologically normally fertilization (2 polar bodies, 2 prounclei) compared with 75% of fresh eggs (difference significant, P〈 0.01). About 13% of eggs were polyspermic in both categories. The most common anomaly in aged fertilied egges was failure to extrude the second polor body (23% off eggs vs 8% of fresh eggs, P 〈 0.01). Only 21% of aged eggs underwent first cleavaage, and only 74% of these appeared morphologically normal, compared with value of 68% and 98%, respectively, for fresh eggs. These data show that in the hamster, abnormal fertilization and cleavage failure can, in part, be directly attributed to postovulatory deterioration of eggs. We also infer that the apparently very short penetrable life of hamster eggs in vivo shown by previous investigators is an indirect effect of postovulatory changes in the female reproductive tract that are unfavorable for sperm-egg interactions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120080303
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  • 14
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    Comparison of strains and culture media used for mouse in vitro fertilization (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 7 (1983), S. 103-109 
    Details
    ISSN: 0148-7280
    Keywords: mouse ; strains ; media ; fertilization ; in vitro ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Success rates of superovulation in response to gonadotropic hormone treatment and in vitro fertilization (ie, mitotic cleavage following insemination) of mouse eggs from outbred CD-1, hybrid CB6Fl, or hybrid B6CBAF1, mice were compared using either a mouse inseminationmedium, modified Krebs-Ringer-bicarbonate (m-KRB), or a human insemination medium, Ham's F10 nutrient mixture. Inseminations were performed in either organ culture dishes or screw-top, flat-side tissue culture tubes. Mean superovulation rates (± SD) were 24.2 (5.1) for CD-1, 33.0 (5.8) for CB6F1, and 16.3 (6.6) for B6CBAF1 mice. For in vitro cleavage the best combination of mouse strain, insemination medium, and culture container was achieved using CB6F1, mice, m-KRB medium, and culture tubes. However, Ham's medium used with either hybrid mouse strain was shown to be employable for fertilization of mouse eggs in vitro as a quality control assay and/or experimental model system for testing the human in vitro fertilization procedure.
    Additional Material: 4 Tab.
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    URL: http://dx.doi.org/10.1002/mrd.1120070202
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  • 15
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    A species-specific sperm factor dispersing the jelly coat of the egg of the sea urchin, Anthocidaris crassispina (1983)
    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 279-293 
    Details
    ISSN: 0148-7280
    Keywords: fertilization ; jelly coat ; species specificity ; sperm enzyme ; sea urchin ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A species-specific factor capable of disersing the jelly coat surrounding eggs has been purified from sperm of the sea urchin, Anthocidaris crassisina. It does not exert its effect on the vitelline layer. The purification has been accomlished by a four-step procedure involving ammonium sulfate fractionation, gel filtration on Sepharose CL-4B, ion-exchange column chromatography on DEAE-cellulose, and affinity column chromatograhy on heparin-Seharose CL-6B. The isolated factor is homogenous in sodium dodecyl sulfate polyacrylamide gel electrohoresis in the presence or absence of β-mercatoethanol, estimated molecular weight being about 140,000.The jelly dispersion by the present factor is activated by CaCl2, and inhibited by KCl, MnCl2, EDTA, and EGTA, and by sulfated saccharides such as chondroitin sulfate A and C, heparin, and glucose-6-sulfate, Inorganic sulfated such as (NH4)2SO4 and Na2SO4 have no effect on jelly dispersion. This factor is heat-labile, its activity in 30 min at 50°C.The present factor is found also in the seminal Plasma, and released from sperm themselves by treatment with Triton X-100 .These results suggest that this factor is loosely bound to the serm surface. Although glycosidase and arylsulfatase activities are detectable in the seminal plasma, these enzyme activities are not detectable in the purified jelly disersing factor.Only trypsin and α chymotrysin among commercial enzymes tested dispersing activity is inhibited neither by trypsin inhibitors such as N-α-p-tosyl-L-lysine-chloromethyl ketone, soybean trypsin inhibitor, ovomucoid trypsin inhibitor, nor by chymotrypsin inhibitors such as L-1-tosylamide-2 pheny-ethylcholoromethyl ketone and chymostatin Participation of trysin-like and chymotrypsin-like enzymes in jelly dispersion seems unlikely.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120080308
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  • 16
    Electronic Resource
    Electronic Resource
    Effects of magnetic field exposure on fertilization success in rainbow trout, Salmo gairdneri (1983)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 4 (1983), S. 295-301 
    Details
    ISSN: 0197-8462
    Keywords: fusion reactors ; magnetic fields ; biological effects ; fertilization ; fish ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: The sensitivity of trout ova and sperm to 1-T magnetic fields was investigated. It was determined that (1) overall test results combining seven independent Z-statistics demonstrated a significant (α 〈 0.0001) enhancement of fertilization when ova alone were exposed to the magnetic field prior to fertilization; (2) similarly, overall test results combining Z-statistics from eight independent experiments indicated a significant (α 〈 0.0004) enhancement when sperm alone were exposed; and (3) statistical analysis of nine independent experiments confirmed enhanced fertilization (α 〈 0.0001) when both ova and sperm were exposed to the magnetic field prior to fertilization. Although these data indicated that both ova and sperm were sensitive to magnetic fields, simultaneous exposure of both gametes did not have a greater total effect on fertilization rate than the sum of their individual effects.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250040402
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