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Fertilization Process (fertilization + process)
Selected AbstractsCytoskeletal Changes in Oocytes and Early Embryos During in vitro Fertilization Process in MiceANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010E. Gumus Summary The cytoskeleton plays crucial roles in the development and fertilization of germ cells and in the early embryo development. The growth, maturation and fertilization of oocytes require an active movement and a correct localization of cellular organelles. This is performed by the re-organization of microtubules and actin filaments. Therefore, the aim of the present study was to determine the changes in cytoskeleton during in vitro fertilization process using appropriate immunofluorescence techniques. While the chromatin content was found to be scattered throughout the nucleus during the oocyte maturation period, it was seen only around nucleolus following the completion of the maturation. Microtubules, during oocyte maturation, were regularly distributed throughout the ooplasm which was then localized in the subcortical region of oocytes. Similarly microfilaments were scattered throughout the ooplasm during the oocyte maturation period whereas they were seen in the subcortical region around the polar body and above the meiotic spindle throughout the late developmental stages. In conclusion, those changes occurred in microtubules and microfilaments might be closely related to the re-organization of the genetic material during the oocyte maturation and early embryo development. [source] Flow cytometric technique for determination of prostasomal quantity, size and expression of CD10, CD13, CD26 and CD59 in human seminal plasmaINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2006LENA CARLSSON Summary Prostasomes are prostate-derived organelles in seminal plasma exhibiting pluripotent properties to facilitate the fertilization process. Seminal prostasome concentration, size distribution and expression of the prostasomal surface antigens CD10, CD13, CD26 and CD59 were examined by flow cytometry. The study group consisted of 79 men with involuntary infertility. Very strong correlations existed between the prostasome expressions of the different CD markers. Significant correlations between prostasome concentration and CD molecules were weak or lacking. Further, no or weak relationships were observed between the prostasomal CD markers and sperm morphology, seminal fructose, neutral , -glucosidase activity, zinc and tumour necrosis factor , concentrations. Flow cytometry is a practical way to study prostasomes in seminal fluid without prior separation. This is a new technique for evaluation of the role of prostasomes and their functions in male reproductive physiology. [source] The influence of ovarian fluid on Solea senegalensis sperm motilityJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010P. Diogo Summary The role of ovarian fluid in fertilization has been neglected, particularly in marine species. The aim of this work was therefore to assess the influence of ovarian fluid (OF) as a potential contributor factor to sperm motility in Solea senegalensis. The specificity of interactions between sperm and ovarian fluid was analyzed using homologous and heterelogous ovarian fluid. Additional tests tried to identify the most useful concentration for improving sperm motility throughout the activation process. Ovarian fluid solutions were diluted in artificial seawater (SW) (v:v) 0 : 100, 25 : 75, 50 : 50, 75 : 25 and 100 : 0 (OF:SW). Pure ovarian fluid solutions (100%) did not promote sperm motility by themselves since they lack the osmolarity needed to trigger sperm motility. With 75% of ovarian fluid the activation solution promoted a deficient activation and the best concentrations used were 25 and 50%. The presence of ovarian fluid affected significantly total motility (TM) and progressive motility (PM) in the last seconds post activation. Progressive motility was higher at 45 s for homologous 25% OF (20.4%) than control (9.4%). Homologous 25% OF increased significantly TM and PM at 60 s post activation (32.0 and 10.5%, respectively) when compared to control (15.8 and 1.7%, respectively). Sperm velocity showed significant differences in the presence of ovarian fluid since early seconds post activation. Our data revealed an enhancement of sperm motility with ovarian fluid at low concentrations in the activation solution. There seems to be a high degree of specificity of ovarian fluid-sperm interaction since heterologous fluid had a lower performance enhancing sperm motility than homologous fluid. Our results indicated a possible important female contribution to sperm motility enhancement during the fertilization process in S. senegalensis. [source] The significance of platelet-activating factor and fertility in the male primate: a reviewJOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2005William E. Roudebush Abstract:, Since its discovery nearly 30 years ago platelet-activating factor (PAF) has emerged as one of the more important lipid mediators known. PAF (1- O -alkyl-2- O -acetyl- sn -glycero-3-phosphorylcholine) exists endogenously as a mixture of molecular species with structural variants of the alkyl moiety. PAF is a novel potent signaling phospholipid that has unique pleiotropic biological properties in addition to platelet activation. PAF also plays a significant role in reproduction and is present in the sperm of a number of primate species. PAF content in squirrel monkey sperm is significantly higher during the breeding season than the non-breeding season. PAF content in rhesus sperm has a significant relationship with sperm motility. PAF content in human sperm has a positive correlation with seminal parameters and pregnancy outcomes. The enzymes (lyso-PAF-acetyltransferase and PAF-acetylhydrolase) necessary for PAF activation and deactivation are present in primate sperm. PAF-acetylhydrolase may act as a ,decapacitation factor'. Removal of this enzyme during capacitation promotes PAF synthesis increasing primate motility and fertilization. PAF also plays a significant role in the fertilization process, enhancing the fertilization rates of oocytes. Enhanced embryo development has also been reported in oocytes fertilized with PAF-treated sperm. Exogenous PAF will also significantly improve primate artificial insemination pregnancy outcomes. PAF antagonists inhibit sperm motility, acrosome reaction, and fertilization thus suggesting the presence of receptors for PAF. The PAF-receptor is present on primate sperm, with altered transcript levels and distribution patterns on abnormal cells. Whereas, the exact mechanism of PAF in sperm function and reproduction is uncertain, its importance in normal primate fertility is substantial. [source] Expression of Progesterone Receptor in the Utero-tubal Junction After Intra-uterine and Deep Intra-uterine Insemination in SowsREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2010P Tummaruk Contents The aim of this study was to investigate the expression of progesterone receptor (PR) in the utero-tubal junction (UTJ) of sows at 24 h after intra-uterine insemination (IUI) and deep intra-uterine insemination (DIUI) compared with conventional artificial insemination (AI) in pigs. Fifteen multiparous sows were used: AI (n = 5), IUI (n = 5) and DIUI (n = 5). The sows were inseminated with a single dose of diluted semen during the second oestrus after weaning at 6,8 h prior to ovulation (AI: 3000 × 106 spermatozoa, IUI: 1000 × 106 spermatozoa and DIUI: 150 × 106 spermatozoa). The UTJ was collected and subject to immunohistochemical staining using avidin-biotin immunoperoxidase technique with mouse monoclonal antibody to PR. In the oviductal part of the UTJ, the intensity of PR in the tunica muscularis and the proportion of PR-positive cells in the surface epithelium after DIUI were lower than AI (p < 0.05). The intensity and the proportion of PR-positive cells between AI and IUI in all compartments of the UTJ did not differ significantly (p > 0.05). When comparing between tissue compartments, prominent staining was observed in the muscular layer of the UTJ. It could be concluded that the expression of PR in the UTJ prior to fertilization after DIUI with a reduced number of spermatozoa was lower than that after AI. This might influence sperm transportation and the fertilization process. [source] Effect of Prostatein, the Major Protein Produced by the Rat Ventral Prostate, on Phagocytic Cell FunctionsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2003Mariana Maccioni Problem:, To determine whether prostatein, the major protein produced and secreted into the seminal fluid by the rat ventral prostate has any effect on the phagocytic cell functions in vitro. Method of study:, Analysis was done by determining if purified prostatein added to cells obtained from the peritoneal cavity has any effect on their phagocytic and intracellular killing capacity. Also, we analyzed the effect of prostatein on the production of oxygen and nitrogen intermediates, measuring these metabolites by Nitroblue tetrazolium assay and by the Griess reaction respectively. Results:, Prostatein possess the ability to inhibit in vitro the phagocytic and killing properties of peritoneal rat leukocytes in a dose-dependent manner. The addition of a polyclonal antiserum against prostatein specifically blocks this inhibitory effect. Moreover, prostatein inhibits the production of oxygen and nitrogen intermediates by these cells. Conclusion:, Regulation of the production of reactive oxygen species in the reproductive tract is extremely necessary to avoid their deleterious effects on the sperm motility and the fertilization process. We propose that prostatein, a protein supplied by an accessory gland like prostate, can inhibit the macrophage function, showing an important antioxidant effect. [source] Cytoskeletal Changes in Oocytes and Early Embryos During in vitro Fertilization Process in MiceANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010E. Gumus Summary The cytoskeleton plays crucial roles in the development and fertilization of germ cells and in the early embryo development. The growth, maturation and fertilization of oocytes require an active movement and a correct localization of cellular organelles. This is performed by the re-organization of microtubules and actin filaments. Therefore, the aim of the present study was to determine the changes in cytoskeleton during in vitro fertilization process using appropriate immunofluorescence techniques. While the chromatin content was found to be scattered throughout the nucleus during the oocyte maturation period, it was seen only around nucleolus following the completion of the maturation. Microtubules, during oocyte maturation, were regularly distributed throughout the ooplasm which was then localized in the subcortical region of oocytes. Similarly microfilaments were scattered throughout the ooplasm during the oocyte maturation period whereas they were seen in the subcortical region around the polar body and above the meiotic spindle throughout the late developmental stages. In conclusion, those changes occurred in microtubules and microfilaments might be closely related to the re-organization of the genetic material during the oocyte maturation and early embryo development. [source] Effects of tributyltin(IV) chloride on the gametes and fertilization of Ascidia malaca (Ascidiacea: Tunicata)APPLIED ORGANOMETALLIC CHEMISTRY, Issue 2 2003L. Villa Abstract Ascidia malaca gametes before fertilization incubated in 10,5 or 10,7,M solutions of tributyltin(IV) chloride, TBTCl, for 3,h appear highly damaged under transmission electron microscopy observation. Also, the fertilization process is affected by the compound: the damaged spermatozoa are present in the vitelline coat and the egg does not cleave. An increase of microbodies, structurally similar to peroxisomes, have been detected in the egg peripheral cytoplasm, probably in relation to their role in alleviating damage to some cellular components. The results have shown that the reproduction of ascidians under unfavourable environmental conditions is prevented. Copyright © 2003 John Wiley & Sons, Ltd. [source] RECENT ADVANCES IN FERTILIZATION ECOLOGY OF MACROALGAE,JOURNAL OF PHYCOLOGY, Issue 1 2002Bernabé SantelicesArticle first published online: 19 FEB 200 Our understanding of natural patterns of fertilization in seaweeds has increased substantially over the last 10 years due to new approaches and methods to characterize the nature and frequency of fertilization processes in situ, to recognize the conditions and mechanisms enhancing fertilization success, and to anticipate population and community consequences of the patterns of natural fertilization. Successful reproduction in many species depends on a delicate juxtaposition of abiotic and biotic conditions. Important abiotic factors are those triggering gamete release (e.g. single or interacting effects of light quality and water movement) and those affecting gamete viability or concentrations (e.g. salinity effects on polyspermy blocks; gamete dilution due to water movement). Examples of important biotic components are synchronous gamete release, efficiency of polyspermy-blocking mechanisms, population density of sexually fertile thalli, interparent distances, and male-to-female ratios. Field data indicate fertilization frequencies of 70%,100% in broadcasting-type seaweeds (e.g. fucoids) and 30%,80% in brooding-type (red) algae. Red algal values are higher than previously thought and challenge presently accepted explanations for their complex life histories. Important population and community questions raised by the recent findings relate to the magnitude of gene flow and exchange occurring in many micropopulations that seemingly breed during periods of isolation, the physiological basis and population effects of male-to-male competition and sexual selection during fertilization of brooding seaweeds, and the effects of massive gamete release, especially in holocarpic seaweeds, on benthic and planktonic communities. Comparative studies in other algal groups are now needed to test the generality of the above patterns, to provide critical pieces of information still missing in our understanding of natural fertilization processes, and to elucidate the evolutionary consequences of the different modes of reproduction (e.g. brooders vs. broadcasters). [source] | |||||||||||||