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Biomedical subjects

J Tesarík

Publications and source records attributed to J Tesarík.

At least 55 records · Page 3Linked to original sources
PubMed1985

Comparison of acrosome reaction-inducing activities of human cumulus oophorus, follicular fluid and ionophore A23187 in human sperm populations of proven fertilizing ability in vitro.

Significant differences in the frequency of spontaneous and induced acrosome reactions (identified by electron microscopy) were detected between 5 individual sperm samples. Maximal stimulation of the acrosome reaction was achieved with ionophore A23187, no differences being detected between the two preincubation times used (5 and 15 h). The cumulus oophorus and follicular fluid caused a similar increase in the proportion of acrosome-reacted spermatozoa after 5 h of preincubation. It is concluded that specific products of the cumulus and/or granulosa cells may contribute to the acrosome reaction-inducing activity of human follicular fluid.

Acrosome↗
PubMed1984

Topographical relations of intramembrane particle distribution patterns in human sperm membranes.

The distribution of intramembrane particles in human sperm membranes has been explored with particular reference to the topographical region of the sperm cell and the membranes' fracture face. Conspicuous differences in the size, arrangement, density, and lateral mobility of intramembrane particles between some topographically distinct membrane domains are demonstrated. The greatest regionality is exhibited by the plasma membrane. In sperm head regions, it shows a significant variability and changes its particle distribution during culture in capacitating medium. In contrast, little variability and no changes during the incubation are seen in the acrosomal and nuclear membranes. Striking is the difference in particle distribution on the E face of the outer acrosomal membrane between the acrosomal and equatorial regions. It is suggested that the invariable regional difference in the organization of the outer acrosomal membrane may bear on the different behavior of its two main domains during sperm capacitation and acrosome reaction.

Acrosome↗
PubMed1984

[Personal experience with in vitro fertilization and embryo transfer].

The causes of sterility could be better characterized in 49 so called complex laparoscopies with estimation of sperm ascension and extraction of oocytes following hormonal stimulation. Oocytes could be obtained in sterility operations. They have been fertilized and transferred into the tubes, with the result of 2 pregnancies after 49 such procedures. Up to now there is no late pregnancy after 115 in vitro fertilizations and 53 embryo transfer into the uterus.

Embryo Transfer↗
PubMed1984

Selective binding of human cumulus cell-secreted glycoproteins to human spermatozoa during capacitation in vitro.

The results of this study demonstrate that glycoproteins manufactured by human cumulus cells can be detected bound to human spermatozoa incubated in capacitational medium containing the labeled cumulus-cell secretions. Cumulus-cell-secreted glycoproteins were labeled with a mixture of 3H-methionine and 3H-tryptophan or with 3H-fucose, and the binding of the labeled compounds to spermatozoa was evaluated by autoradiography. The binding was highly selective, involving only approximately 1% of the samples of spermatozoa used. The results suggest that the binding of cumulus-cell-secreted glycoproteins to spermatozoa may represent a final and highly selective step in human sperm capacitation.

Adult↗
PubMed1983

Oocyte recovery, in vitro insemination, and transfer into the oviduct after its microsurgical repair at a single laparotomy.

A method combining recovery of a preovulatory oocyte, its in vitro insemination, and transfer into the oviduct with tubal microsurgery at a single laparotomy is described. Of four women in whom tubal microsurgery was clinically indicated and the accompanying tubal transfer of an oocyte inseminated in vitro was performed, two became pregnant. It is not clear whether fertilization occurred in vitro or in vivo. One of the pregnancies miscarried in the fifth week after surgery; the other pregnancy continued without any complications. A normal male infant was subsequently delivered at term. The proposed method is discussed as a possible alternative to in vitro fertilization and embryo transfer in some cases of infertility and as a suitable supplemental procedure in some cases in which tubal microsurgery is indicated.

Adult↗
PubMed1983

[Diagnosis of the principle cause for sterility in a couple, based on laparoscopic examination].

A complex laparoscopical approach is demonstrated, whereby clinical failure of spermiogenesis, cervical, ovarian and tubal factor of the female sterility can be detected at a single examination. Spermatozoa are aspirated from the abdominal cavity and peritubal regions following sexual intercourse or artificial "ab uxore" insemination (A. I. D.). If spermatozoa are found, the cervical factor can be excluded and the spermatozoal vitality assessed. The surgery is planned at the periovulatory period after priming a patient with clomiphene (Gravosan Spofa) and HCG (Praedyn Spofa). Follicular fluid is aspirated from large preovulatory follicles and search is done for oocytes whose maturational stage is correlated with plasma hormone levels. The examination is completed with chromoperturbation of oviducts. Out of 23 such laparoscopic examinations, the diagnosis was set down in 18 cases and 6 women became pregnant after treatment.

Adult↗
PubMed1982

Fine structure of human two-cell ova fertilized and cleaved in vitro.

The human two-cell ovum consists of two equally sized blastomeres, surrounded by the zona pellucida. Cumulus cells may be apposed to the exterior of the zona. The blastomere nuclei contain spherical nucleoli, made up of fibrillar matrix, and randomly dispersed chromatin. The cytoplasmic structures include mitochondria, smooth endoplasmic reticulum, annulate lamellas, the Golgi complex, free ribosomes, secondary lysosomes, cortical granules, and microtubules. The cell membrane bristles with microvilli and displays signs of pinocytosis except at the site of apposition of the two blastomeres. The fine structure of the two-cell ova fertilized and cleaved in vitro corresponds with the presumptive pattern with respect to the current knowledge of mammalian embryo preimplantation development. The ova seem to have been capable of further growth.

Adult↗