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1.
This review refers to the evolution of ooplasmic injectionsof round spermatid nuclei ROSNI) or intact round spermatidsROSI). Conclusions from their preliminary application in thehamster, rabbit, mouse and human are discussed. Criteria foridentification of round spermatids and guidelines/quality controlfor application of ROSNI/ROSI techniques are emphasized. Althoughall the animal offspring and the human newborns delivered afterROSNI/ROSI are healthy additional research efforts are necessaryto confirm the safety of these procedures and improve theiroutcome  相似文献   
2.
Results from the transplantation of donor male germ cells into xenogeneic recipient seminiferous tubules indicate that donor spermatogonia are capable of differentiating to form spermatozoa morphologically characteristic of the donor species. Germ cell transplantation procedures combined with developments in freezing, culturing or enriching germ cell populations have applications of paramount importance in medicine, basic sciences and animal reproduction. Additionally, these techniques can serve as an alternative approach for gonadal protection and fertility preservation in patients with cancer. This article is a chronological critical review of the technological advances that followed the initial successful transplantation of mouse germ cells into recipient mice. Furthermore, the factors responsible for the immunological privilege properties of the testis and the parameters influencing the potential of mammalian germ cells to undergo mitosis and meiosis within a xenogeneic testis are described. Finally, the role of human germ cell transplantation procedures in the therapeutic management of non-obstructive azoospermia is discussed.  相似文献   
3.
The role of a telomerase assay in the recognition of Sertoli cell-only syndrome with testicular foci of haploid cells was evaluated. Men with Sertoli cell-only syndrome (n = 23) were given a new diagnostic testicular biopsy. Part of the biopsy was stained and the remainder was processed for the quantitative telomerase assay. After 3-13 months, a therapeutic testicular biopsy was performed. This material was minced and then examined using confocal laser scanning microscopy and fluorescent in-situ hybridization. Histology of diagnostic testicular biopsy material confirmed the diagnosis of Sertoli cell-only syndrome in all the participants. All seven men with a telomerase assay value in their diagnostic testicular biopsy of >42 total product generated (TPG) U/microg protein had haploid cells (i.e. spermatozoa and/or spermatids) in their therapeutic testicular biopsy. Among participants with telomerase assay values <42 TPG U/microg protein, only one man had haploid cells in his therapeutic testicular biopsy. Thus, telomerase assay values >42 TPG U/microg protein in the diagnostic biopsy identified 87.5% of the Sertoli cell-only syndrome men with haploid cells in their therapeutic testicular biopsy. Significantly higher values of the telomerase assay were found in men with testicular foci of haploid cells than in men without these foci. The use of a quantitative telomerase assay biopsy appears to be important for identifying those men with Sertoli cell-only syndrome who have foci of haploid cells and can be candidates for assisted reproduction techniques.  相似文献   
4.
Purpose: Our objective was to apply ooplasmic round spermatid nuclear injections for the treatment of nonobstructive azoospermia. Materials: Participants were nine azoospermic men who had previously undergone diagnostic testicular biopsy. Spermatogenetic arrest was diagnosed at the round spermatid stage (n=6) or primary spermatocyte stage (n=3). A second (therapeutic) testicular biopsy was performed and round spermatid nuclei were recovered from all the participants. Results: Forty-nine mature oocytes were successfully injected with nuclei and then cultured for 72 hr. Twenty-four embryos were transferred to nine women. No pregnancy was achieved. Conclusions: Round spermatids can be recovered from therapeutic testicular biopsy material of men negative for round spermatids in previous routine diagnostic testicular biopsy specimens. Round spermatid nuclear injections may play a role in the treatment of nonobstructive azoospermia.  相似文献   
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6.
This study was performed to examine the contribution of genetic polymorphism of oestrogen and androgen receptor (AR) genes in male infertility. We have studied in total 173 Greek men, 109 infertile patients and 64 controls (group A). Patients were divided in to three subgroups: group B (n=29) with idiopathic moderate oligospermia, group C (n=42) with azoospermia or idiopathic severe oligospermia and group D (n=38) with azoospermia or oligospermia of various known aetiologies. All patients and controls were genotyped for two polymorphisms of the oestrogen receptor alpha (ERalpha) gene and also for the (CAG)n repeat length polymorphism of the X-linked androgen receptor (AR)gene. The control group had statistically significant difference from group C regarding the XbaI polymorphism of ERalpha gene. Despite the fact that we did not observe any statistically significant differences in the mean and range of the CAG repeat number, the frequency of the higher repeats of the nucleotide repeat sequence (CAG)n of the AR gene was 2-4 times higher in groups B and C compared with the control group A. Our results indicate that both ERalpha and AR gene play significant role in male fertility. It is possible that a synergy may exist between unfavourable genotypes of these two genes in male infertility.  相似文献   
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8.
Throughout the past six decades, our understanding of cancer of the prostate and the treatment of the disease using endocrine therapy has been centred on the classical investigations of Charles Huggins, which established that tumor tissue of the prostate as well as the normal tissue of the gland retained some degree of androgen dependence. Attention must now be focussed on the 20-40% of patients who are resistant to endocrine therapy. These patients are non-responders to conventional endocrine treatment after 3 to 6 months, quickly progress and die of the disease. In terms of molecular endocrinology related to the progressive stage of the disease, it would be expected that the cancer is being driven by the uncontrolled action of growth factors. Experiments combining oligonucleotide treatment with cytotoxic chemotherapeutic agents demonstrated a marked increase in the sensitivity of the prostate cancer cells. Results indicate that despite the presence of Bcl-x pre-mRNA in a number of cell types, the effects of modification of its splicing by antisense oligonucleotides vary depending on the expression profile of the treated cells. The transition from androgen-dependent to androgen non-dependent prostate cancer is accompanied by a number of molecular genetic changes, including overexpression of the Bcl-2 gene. Overexpression of Bcl-2 protein decreases the pro-apoptotic response to such cellular insults as irradiation, chemotherapy, and androgen withdrawal. The future looks promising and this kind of treatment offers a novel approach to alternative therapeutic options for advanced prostate cancer. Although numerous chemotherapeutic regimens have been evaluated for patients with hormone-refractory prostate cancer, none has improved survival.  相似文献   
9.
Investigation of the developmental potential post-injection of a pre-decondensed or non-pre-decondensed sperm head into the female pronucleus of a pre-activated oocyte. Rat pre-activated oocytes were treated with intrapronuclear pre-decondensed sperm head injections (IPSHI) (n = 133) or intrapronuclear non-pre-decondensed sperm head injections (INPSHI) (n = 138). All injected oocytes were transferred to pseudopregnant female recipients. Rat IPSHI techniques resulted in the delivery of five healthy offspring. Rat INPSHI techniques did not result in any pregnancies. Rat IPSHI techniques can result in delivery of healthy offspring. Successful performance of human IPSHI techniques might serve as a novel method to manage cases of intracytoplasmic sperm injection failure due to lack of development of male pronucleus or due to failure in pronuclei fusion.  相似文献   
10.
We evaluated the reproductive potential of frozen/thawed testicular spermatozoa of azoospermic men with left varicocele. The role of testicular tissue telomerase assay (TTA) in the prediction of the presence of testicular spermatozoa pre- and post-varicocelectomy was investigated, as well. Therapeutic testicular biopsy and TTA were performed in 82 nonobstructed azoospermic (NOA) men with varicoceles. Testicular spermatozoa were found in 33 men and processed for cryopreservation. Oocytes were later recovered from the spouses of the latter azoospermic men with varicoceles and injected with frozen/thawed testicular spermatozoa. Among the 49 men who were negative for testicular spermatozoa, 22 men underwent subsequently subinguinal microsurgical varicocelectomy. A total of 198 mature oocytes were successfully injected and 101 were normally fertilized and subsequently cleaved. Transfer of these 101 embryos in 26 women resulted in nine full-term pregnancies. Thirteen healthy babies were delivered. A cut-off value of TTA of 39 TPG U microg(-1) protein had an overall diagnostic accuracy equal to 90.2% to predict the presence of testicular spermatozoa pre-varicocelectomy. Within the group of men who were negative for testicular spermatozoa a cut-off value of TTA equal to 28 TPG U microg(-1) protein (pre-varicocelectomy) had a 84.2 % diagnostic accuracy to recognize the men who would become positive for either ejaculated or testicular spermatozoa post-varicocelectomy. Testicular spermatozoa can be found in 40% of NOA men with left varicocele. Ooplasmic injections with frozen/thawed testicular spermatozoa have a role in the therapeutic management of non-obstructive azoospermia associated with varicocele. Pre-varicocelectomy, a TTA cut-off value equal to 39 TPG U microg(-1) protein has a 90.2% diagnostic accuracy to indicate the men positive/negative for testicular spermatozoa. In addition, pre-varicocelectomy, a cut-off value equal to 28 TPG U microg(-1) protein has a 84.2% diagnostic accuracy to identify those men with varicoceles without testicular spermatozoa, who will become positive/negative for spermatozoa (either ejaculated or testicular) post-varicocelectomy.  相似文献   
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