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1.
Hum Reprod ; 28(5): 1155-60, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23493114

RESUMEN

STUDY QUESTION: Does the health status of infants fathered by nonmosaic Klinefelter syndrome (KS) patients whose partners underwent ICSI with sperm obtained from testicular dissection reveal any genetic risk for the offspring?. SUMMARY ANSWER: KS patients undergoing testicular sperm extraction (TESE) are capable of conceiving healthy children. WHAT IS KNOWN ALREADY: Paternity has been successfully achieved in nonmosaic KS patients (47,XXY karyotype) by ICSI using either ejaculated or testicular spermatozoa. A crucial concern is the potential transmission of genetic abnormalities to the offspring. Some studies reported that 47,XXY spermatogonia are capable of completing spermatogenesis leading to the production of mature spermatozoa with increased aneuploidies. Other authors showed that where focal spermatogenesis is present in nonmosaic KS males, it originates from euploid germ cells and, therefore, produces normal mature gametes. In support of this finding, at present, the great majority of children born from nonmosaic KS patients are chromosomally normal. STUDY DESIGN, SIZE, DURATION: From April 2004 to June 2010, 38 azoospermic patients with nonmosaic KS were examined for the presence of testicular spermatozoa. Spermatozoa were retrieved from 15 patients and 26 ICSI cycles were done (16 with cryopreserved sperm). There were 15 pregnancies leading to the birth of 16 babies who were karyotyped at amniocentesis and after birth. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were recruited from couples attending the European Hospital, Rome, and Clinica MAR&Gen, Granada, for infertility treatment. Both the European Hospital and Clinica MAR&Gen are private clinics. Testicular tissue was extracted with TESE or micro-TESE. After retrieval, fresh sperm was used for ICSI or it was cryopreserved for future use. MAIN RESULTS AND THE ROLE OF CHANCE: Spermatozoa were retrieved from 15 patients (14 TESE and 1 micro-TESE) out of 38 (39.5%). A total of 26 ICSI cycles were performed: 10 with fresh and 16 with cryopreserved-thawed sperm. Mean ages (y) of patients with positive and negative sperm retrieval were, respectively, 34.8 ± 1.72 and 35.6 ± 4.08 (NS, nonsignificant). Comparing ICSI cycles performed with fresh sperm (n = 10) to those performed with frozen-thawed sperm (n = 16): Fertilization rates per injected oocyte were 53.0% (44 of 83) and 47.8% (32 of 67), respectively (NS). The cleavage rate per injected oocyte was 90.6% (29 of 32) versus 68.2% (30 of 44); P = 0.026. Clinical outcomes were not significantly different between the fresh and the frozen-thawed sperm group: clinical pregnancy rates were 7 of 10 (70.0%) and 8 of 16 (50.0%); implanted embryos (per transferred embryo) were 8 of 23 (34.8%) and 8 of 29 (27.6%); delivery rates were 6 of 10 (60.0%) and 5 of 16 (31.3%). Sixteen babies were born, all of them are healthy with a normal karyotype, eight from the fresh sperm group and eight from the frozen-thawed sperm group. LIMITATIONS, REASONS FOR CAUTIONS: The small numbers available for study mean that only common problems can be excluded. WIDER IMPLICATIONS OF THE FINDINGS: This study provides further reassurance that KS men can father healthy children and that pre-implantation genetic diagnosis on embryos conceived with their sperm is not strongly indicated. However, until conclusive information is available, such couples should be offered extensive genetic counseling. STUDY FUNDING/COMPETING INTEREST(S): No external funding was obtained for the present study. None of the authors has any conflict of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Asunto(s)
Síndrome de Klinefelter/genética , Inyecciones de Esperma Intracitoplasmáticas/métodos , Adulto , Amniocentesis , Aneuploidia , Biopsia , Criopreservación , Padre , Femenino , Humanos , Cariotipificación , Síndrome de Klinefelter/diagnóstico , Masculino , Embarazo , Resultado del Embarazo , Recuperación de la Esperma , Espermatogénesis , Espermatozoides/patología , Testículo/cirugía
2.
Reprod Biomed Online ; 14(5): 572-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17509196

RESUMEN

Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.


Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Inducción de la Ovulación/métodos , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Transferencia de Embrión , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Italia , Legislación Médica , Masculino , Análisis por Apareamiento , Embarazo
3.
Reprod Biomed Online ; 7(5): 558-62, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14680548

RESUMEN

The X-linked dominant form of Charcot-Marie-Tooth syndrome (CMTX) is a clinically and genetically heterogeneous hereditary disorder of the peripheral nerves caused by mutations in the GJB1 gene that encodes a gap junction protein named connexin 32 (Cx32). Clinically, CMTX is characterized by peripheral motor and sensory deficit with muscle atrophy. A couple with a previous history of pregnancy termination after being diagnosed positive for CMTX by chorionic villus sampling, was referred for preimplantation genetic diagnosis (PGD). The female partner carried the causative H94Q, characterized by a C-->G substitution in codon 94 of exon 2 of the GJB1 gene. Embryos obtained after intracytoplasmic sperm injection (ICSI) were evaluated for the presence of the mother's mutation using polymerase chain reaction (PCR), followed by mutation analysis performed using the minisequencing method. Amelogenin sequences on the X and Y chromosomes were also co-amplified to provide a correlation between embryo gender and mutation presence. A single PGD cycle was performed, involving nine fertilized oocytes, five of which developed into good quality embryos useful for biopsy. Two unaffected embryos were transferred, resulting in a singleton pregnancy followed by the birth of a healthy female.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Enfermedad de Charcot-Marie-Tooth/genética , Cromosomas Humanos X , Diagnóstico Preimplantación , Adulto , Amelogenina , Conexinas/genética , Análisis Mutacional de ADN , Proteínas del Esmalte Dental/genética , Transferencia de Embrión , Femenino , Ligamiento Genético , Humanos , Masculino , Mutación , Reacción en Cadena de la Polimerasa , Inyecciones de Esperma Intracitoplasmáticas , Proteína beta1 de Unión Comunicante
4.
Hum Reprod ; 17(8): 2160-4, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12151452

RESUMEN

BACKGROUND: The aim of our study was to evaluate the possibility of embryonic or somatic cell haploidization after fusion with intact or enucleated immature oocytes which were subsequently cultured in vitro. Embryonic or somatic cell nuclei do not undergo premature chromosome condensation when fused to intact or enucleated immature oocytes whose maturation is prevented by dibutyryl cyclic AMP (dbcAMP). The presence of dbcAMP permits, however, the completion of DNA replication in somatic cell nuclei. METHODS AND RESULTS: The chromosomes condensed when the reconstructed cells were released from the dbcAMP block. When somatic or embryonic nuclei were introduced into intact immature meiotically competent oocytes and subsequently cultured their chromosomes assembled on a common spindle with meiotic chromosomes and proceeded through the meiotic-like division, judged according to the presence of the first polar body extruded. When embryonic cell nuclei were introduced into cytoplasts obtained from immature meiotically competent oocytes, polar bodies were extruded in about 75% of reconstructed cells but the metaphase plates were abnormal in almost all cases. When somatic cell nuclei were inserted into the above cytoplasts, polar bodies were extruded only very exceptionally and in these cells chromosomes were arranged in abortive metaphase plates. CONCLUSIONS: Our results suggest that somatic cell nuclei are unable to proceed through the reduction division (haploidization) when introduced into an immature oocyte meiotic cytoplasm.


Asunto(s)
Citoplasma/fisiología , Embrión de Mamíferos/citología , Técnicas de Transferencia Nuclear , Oocitos/fisiología , Animales , Bucladesina/farmacología , Senescencia Celular/fisiología , Cromosomas/efectos de los fármacos , Cromosomas/fisiología , Femenino , Haploidia , Meiosis/fisiología , Metafase , Ratones , Oocitos/citología
5.
Fertil Steril ; 74(5): 1044-6, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11056258

RESUMEN

OBJECTIVE: To examine whether the results of assisted reproduction with the use of elongated spermatids from a man with incomplete arrest of spermiogenesis and a high frequency of apoptosis among postmeiotic germ cells can be improved by germ cell in vitro culture. DESIGN: Case report. SETTING: Private assisted reproduction centers and a university department. PATIENT(S): Man with incomplete spermiogenesis failure. INTERVENTION(S): Testicular spermatid extraction, in vitro culture of testicular biopsy samples, intraoocyte injection of elongated spermatids, embryo culture, and transfer. MAIN OUTCOME MEASURE(S): Fertilization rate, embryo morphology, and pregnancy. RESULT(S): An assisted reproduction attempt with viability-selected elongated spermatids from a fresh testicular biopsy sample resulted in a poor fertilization result and embryo quality. Further analysis of the sample used in this attempt showed a high incidence of apoptosis among postmeiotic germ cells. A second attempt was then performed with in vitro culture of testicular cells for 24 hours before spermatid injection. This procedure led to a significant decrease in the frequency of apoptosis among viability-selected spermatids, to improvement of the fertilization rate and embryo quality, and to the birth of healthy twins. CONCLUSION(S): In vitro culture of testicular biopsy samples before assisted reproduction with elongated spermatids may improve the efficacy of treatment in cases of massive in vivo apoptosis of postmeiotic germ cells.


Asunto(s)
Apoptosis , Fertilización In Vitro , Trabajo de Parto , Meiosis/fisiología , Espermátides/citología , Espermátides/fisiología , Gemelos , Adulto , Biopsia , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Retratamiento , Testículo/patología
6.
Hum Reprod ; 15(11): 2269-77, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11056118

RESUMEN

In patients with non-obstructive azoospermia, testicular sperm extraction (TESE) is a method of choice to recover spermatozoa as a male therapeutic approach in intracytoplasmic sperm injection (ICSI) programmes. However, the efficacy of TESE in this indication is burdened by a frequent failure of sperm recovery, which renders useless both the invasive testicular intervention and ovarian stimulation of the patient's spouse. One of the most frequent pathological pictures characterizing complete absence of spermatozoa is germinal aplasia (Sertoli cell- only syndrome or SCOS). Two different histological patterns of SCOS have been already described during the past five decades. These two patterns can be characterized as the congenital (pure) and the secondary (mixed) forms. Both patterns, with different prognosis to retrieve spermatozoa by therapeutic testicular biopsy, are frequently confused when TESE is performed during ICSI programmes. Useful criteria to predict the absence of spermatozoa can be obtained by a definite recognition of the two typical histological patterns during the diagnostic testicular biopsy. The diagnosis of congenital or acquired SCOS can be refined by endocrine, chemical, immunohistochemical and molecular biology aids. Reduction of both sperm retrieval failure and unnecessary ovarian stimulation can be achieved by combination of these methods.


Asunto(s)
Oligospermia/patología , Células de Sertoli/patología , Manejo de Especímenes/métodos , Espermatozoides/patología , Testículo/patología , Predicción , Humanos , Masculino , Enfermedades Testiculares/patología
7.
Hum Reprod ; 15(8): 1713-6, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10920091

RESUMEN

In some men with germ cell maturation arrest, spermatogenesis can be resumed during in-vitro culture of testicular biopsy samples. In this study, we examined whether similar differentiation events can be induced in cultured germ cells from cryopreserved testicular biopsy specimens. Fresh and cryopreserved aliquots of the same testicular biopsy samples were cultured in medium supplemented with FSH and testosterone. After 24 and 48 h of culture, the progression of spermatogenesis and the percentage of Sertoli cells with DNA damage, detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), were evaluated. Spermatogenesis progressed in a similar way in fresh and cryopreserved aliquots over the first 24 h of culture. However, in contrast to fresh aliquots, no additional progress of spermatogenesis was detected between the 24 and 48 h time points. The percentage of TUNEL-positive Sertoli cells in fresh aliquots showed only a moderate increase after 24 h of culture, whereas most Sertoli cells from cryopreserved aliquots became TUNEL-positive during the same culture period. These data show that limited progression of spermatogenesis can be achieved by culturing cryopreserved testicular biopsy specimens for 24 h, but no additional benefit can be expected from prolonging the culture beyond this time point.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Espermatozoides/citología , Testículo/citología , Biopsia/métodos , Criopreservación , Medios de Cultivo , Daño del ADN , Hormona Folículo Estimulante/farmacología , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Oligospermia/patología , Células de Sertoli/fisiología , Espermatogénesis , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología , Testículo/fisiología , Testosterona/farmacología
8.
Fertil Steril ; 72(5): 809-13, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10560982

RESUMEN

OBJECTIVE: To evaluate the potential usefulness of in vitro culture of germ cells for distinguishing between healthy and apoptotic spermatids. DESIGN: Prospective study. SETTING: Private assisted reproduction laboratories and a university department. PATIENT(S): Men with secretory azoospermia who were candidates for assisted reproductive treatment. INTERVENTION(S): Testicular biopsy samples were cultured in the presence of FSH and testosterone for 48 hours. Germ cell apoptosis before and after culture was evaluated by terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling. MAIN OUTCOME MEASURE(S): The percentage of germ cells at different stages of spermatogenesis that showed apoptosis-related DNA damage. RESULT(S): In fresh samples, high levels of apoptosis were detected at those stages of spermatogenesis at which major developmental blocks occurred, with a maximum at the most advanced stage detected. In contrast, apoptotic cells were considerably less well represented at the most advanced stage after culture. CONCLUSION(S): In addition to the previously described facilitation of spermatid recognition and the progression of cytoplasmic maturation, in vitro culture of germ cells is useful to overcome the danger of inadvertent use of apoptotic spermatids for assisted reproduction.


Asunto(s)
Oligospermia/patología , Técnicas Reproductivas , Espermátides/citología , Espermatozoides/citología , Apoptosis/fisiología , Separación Celular , Células Cultivadas , Senescencia Celular/fisiología , Humanos , Masculino , Meiosis/fisiología , Estudios Prospectivos
9.
Steroids ; 64(1-2): 22-7, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10323669

RESUMEN

It is known that steroids can induce cell surface receptor aggregation followed by activation of receptor and nonreceptor tyrosine kinases. It has been shown recently that 17beta-estradiol (E2) can stimulate the Src/p21ras/mitogen-activated protein kinase pathway in breast cancer cells, and this effect is supposed to mediate the E2-induced stimulation of breast cancer cell proliferation, possibly via activation of the c-fos and c-jun early genes or of genes involved in cell cycle control. Here we demonstrate the existence of an alternative mechanism of the cancer-promoting effect of E2. Human breast cancer cells (MCF-7) were exposed to the known proapoptotic agent vitamin E succinate (VES), added alone or together with different concentrations of E2. E2 conjugated with bovine serum albumin (E2-BSA), which cannot cross the plasma membrane of living cells, was also used in some experiments to assess whether E2 acted on the cell surface or at intracellular receptors. Apoptosis was analyzed by fluorescence-activated cell sorting after cell staining with propidium iodide and FITC-labeled annexin V. E2 showed a concentration-dependent stimulatory effect on spontaneous apoptosis but inhibited the VES-induced apoptosis. However, effects produced by the same molar concentrations of E2 were different when the hormone was free and when it was used in the form of the E2-BSA conjugate. The effects of E2 and E2-BSA were sensitive to genistein, a tyrosine kinase inhibitor. These data show that E2 modulates apoptosis of breast cancer cells, probably acting both at the cell surface and inside the cells. Tyrosine phosphorylation is involved in the signaling pathways mediating this E2 effect.


Asunto(s)
Apoptosis/fisiología , Neoplasias de la Mama/patología , Transformación Celular Neoplásica , Estradiol/fisiología , Apoptosis/efectos de los fármacos , Activación Enzimática , Humanos , Proteínas Tirosina Quinasas/metabolismo , Tocoferoles , Factor de Transcripción AP-1/metabolismo , Células Tumorales Cultivadas , Vitamina E/análogos & derivados , Vitamina E/farmacología
10.
Hum Reprod ; 14(3): 628-35, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10221687

RESUMEN

Previous studies relating hormone and cytokine concentrations in follicular fluid to oocyte fertilizability were flawed by the uncertainty about the actual oocyte maturity status at the time of recovery and by the possible contribution of the male factor to failures of conventional in-vitro fertilization. This is the first study in which oocyte maturity was assessed immediately after recovery and only mature oocytes were selected for treatment by intracytoplasmic sperm injection. Fertilization outcomes were related to follicular fluid concentrations of 17beta-oestradiol, progesterone, follicle stimulating hormone, luteinizing hormone (LH), growth hormone (GH), prolactin (PRL), interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF alpha). Those oocytes that subsequently showed normal fertilization were harvested from follicles with higher concentrations of progesterone, GH, PRL, IL-1 and TNF alpha as compared with those of oocytes that failed to fertilize. Among the normally fertilized oocytes, low GH concentrations were associated with the failure of cleavage and with poor morphology of cleaving embryos, whereas rapidly cleaving embryos developed from oocytes recovered from follicles with high concentrations of LH and IL-1. These data suggest important roles for GH, IL-1 and TNF alpha, and of residual LH after pituitary suppression, as positive regulators of the final phase of oocyte intrafollicular development.


Asunto(s)
Citocinas/análisis , Fertilización In Vitro/métodos , Líquido Folicular/química , Microinyecciones , Hormonas Hipofisarias/análisis , Esteroides/análisis , Desarrollo Embrionario y Fetal , Estradiol/análisis , Femenino , Hormona Folículo Estimulante/análisis , Hormona de Crecimiento Humana/análisis , Humanos , Interleucina-1/análisis , Hormona Luteinizante/análisis , Masculino , Oocitos/fisiología , Oocitos/ultraestructura , Progesterona/análisis , Prolactina/análisis , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/análisis
11.
Biochem Biophys Res Commun ; 255(1): 23-7, 1999 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-10082649

RESUMEN

Progesterone has previously been shown to exert non-genomic effects on human spermatozoa by opening plasma membrane ion channels and by stimulating protein tyrosine phosphorylation. Here we examined how these two activities are influenced by 11-hydroxyl substitution of the steroid molecule either in the alpha- or in the beta-configuration. Both the 11alpha-OH and the 11beta-OH derivatives of progesterone were more effective than progesterone in stimulating tyrosine phosphorylation, although 11alpha-OH-progesterone was a markedly weaker Ca(2+)-influx inducing agonist than the other two steroids. In Ca(2+)-containing medium, the agonist activity of the 11alpha-OH derivative was weaker than that of the 11beta-OH derivative, and it was completely abolished by genistein, whereas that of progesterone and its 11beta-OH derivative was inhibited only partly by this drug. In contrast, when applied in Ca(2+)-free medium, the 11alpha-OH derivative was the strongest of the three agonists tested, and the effects of all the three steroids were completely abolished by genistein. These data show that the structural motifs of steroid molecules that are responsible for the stimulation of tyrosine phosphorylation are different from those mediating the steroid action on Ca2+ influx through plasma membrane channels. The synthesis of selective agonists of both activities may lead to the development of new pharmacological agents to be used in the treatment of steroid-dependent pathologies.


Asunto(s)
Calcio/metabolismo , Progesterona/química , Progesterona/farmacología , Tirosina/metabolismo , Humanos , Masculino , Fosforilación , Progesterona/análogos & derivados , Transducción de Señal/efectos de los fármacos , Espermatozoides , Relación Estructura-Actividad
13.
Hum Reprod ; 13(1O): 2772-81, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9804229

RESUMEN

In-vitro differentiation of spermatogenic cells is a potential approach to the treatment of male sterility due to spermatogenic arrest. This is a pilot study evaluating meiotic, morphogenetic and cytoplasmic maturation of spermatogenic cells from 18 patients with obstructive azoospermia, during in-vitro culture of partly disintegrated testicular biopsy samples in the presence or absence of recombinant follicle stimulating hormone (rFSH). Meiotic progression was detectable only in the presence of rFSH in culture medium. FSH-dependent condensation, peripheral migration and protrusion of spermatid nuclei, together with FSH-independent flagellar growth, were the main events indicating post-meiotic sperm cell differentiation. rFSH also promoted the progression of spermatid cytoplasmic maturation, reflected by acceleration of acrosomal development. These differentiation events appeared to be mediated by humoral activity of Sertoli cells, without the need for a direct Sertoli-sperm cell contact. These findings provide a background for similar studies in patients with non-obstructive azoospermia. If reproducible in the latter group, transmeiotic in-vitro differentiation of primary spermatocytes may be useful in cases of complete maturation arrest, whereas the development of culture-specific forms may help select viable spermatids in cases of complete spermiogenesis failure.


Asunto(s)
Hormona Folículo Estimulante/farmacología , Oligospermia/patología , Oligospermia/terapia , Espermátides/efectos de los fármacos , Espermátides/patología , Espermatogénesis/efectos de los fármacos , Acrosoma/efectos de los fármacos , Acrosoma/patología , Biopsia , Diferenciación Celular/efectos de los fármacos , Citoplasma/efectos de los fármacos , Citoplasma/patología , Humanos , Técnicas In Vitro , Masculino , Proteínas Recombinantes/farmacología , Técnicas Reproductivas , Espermatocitos/efectos de los fármacos , Espermatocitos/patología , Testículo/patología
14.
Mol Hum Reprod ; 4(8): 757-62, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9733432

RESUMEN

Germ cell apoptosis was evaluated in 11 men suffering from nonobstructive azoospermia and enrolled in a spermatid conception programme. In six of these patients, round spermatids (Sa stage) were the most advanced spermatogenic cells recovered from testicular biopsy samples. This condition is referred to as complete spermiogenesis failure. In the remaining five men, a few late elongated spermatids (Sd stage) were unexpectedly found in the testicular biopsy samples on the day of treatment. This condition is referred to as incomplete spermiogenesis failure. Germ cell apoptosis in both groups of patients was examined by analysing cell smears prepared from mechanically disintegrated testicular tissues using terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), which detects apoptosis-specific DNA fragmentation, and annexin-V binding, detecting apoptosis-related translocation of plasma membrane phosphatidylserine to the membrane's outer surface. Both methods were combined, in double-fluorescence labelling preparations, with immunocytochemical detection of proacrosin, a specific germline marker. Patients with complete spermiogenesis failure had significantly higher frequencies of primary spermatocytes and round spermatids carrying the apoptosis-specific DNA damage in comparison with patients with incomplete spermiogenesis failure. Surprisingly, apoptosis-related phosphatidylserine externalization occurs rarely until the advanced stages of spermiogenesis. Since externalized phosphatidylserine is expected to be involved in the recognition of apoptotic cells by phagocytes, apoptotic spermatocytes and round spermatids may not be removed easily by phagocytosis. The high frequency of DNA damage in round spermatids from patients with complete spermiogenesis failure explains the low success rates of spermatid conception in these cases. The evaluation of apoptosis can help predict success rates of spermatid conception.


Asunto(s)
Apoptosis , Infertilidad Masculina/patología , Espermatogénesis , Espermatozoides/patología , Anexina A5/análisis , Anexina A5/metabolismo , Fragmentación del ADN , Humanos , Masculino , Oligospermia , Fosfatidilserinas/análisis , Fosfatidilserinas/metabolismo , Espermátides/citología
15.
Fertil Steril ; 70(1): 67-70, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9660423

RESUMEN

OBJECTIVE: To use injection of spermatids into oocytes as a mode of infertility treatment in cases in which spermatozoa are not available. DESIGN: Prospective clinical evaluation and case report. SETTING: In Vitro Fertilization Unit, Herzliya Medical Centers, Herzliya-on-Sea, Israel. PATIENT(S): Thirteen couples with male factor infertility in which the male partner lacked spermatozoa in the ejaculate or testicular biopsy samples. INTERVENTION(S): Round spermatid injection and elongated spermatid injection into oocytes. MAIN OUTCOME MEASURE(S): Evaluation of the rate of two-pronucleated and single-nucleated zygote development. RESULT(S): The rate of two-pronucleated zygote development after round spermatid injection and elongated spermatid injection was relatively low (27% and 36%, respectively). Single-nucleated zygotes develop more frequently after round spermatid injection and elongated spermatid injection (35% and 17%, respectively) than after intracytoplasmic sperm injection with mature spermatozoa. A normal pregnancy and childbirth resulted from the transfer of 4 cleaving embryos, each of which developed from a single-nucleated zygote in a round spermatid injection treatment cycle with ejaculated spermatids. CONCLUSION(S): Embryos derived from single-nucleated zygotes after spermatid conception can be viable and give rise to an ongoing clinical pregnancy and childbirth.


Asunto(s)
Transferencia de Embrión , Infertilidad Masculina/fisiopatología , Oocitos/fisiología , Espermátides/fisiología , Espermátides/ultraestructura , Cigoto/fisiología , Adulto , Femenino , Humanos , Masculino , Oligospermia/fisiopatología , Embarazo , Estudios Prospectivos , Resultado del Tratamiento , Cigoto/ultraestructura
19.
Hum Reprod Update ; 3(2): 95-100, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9286733

RESUMEN

Previously published data have suggested that oestradiol exerts direct beneficial effects on human oocytes during in-vitro maturation and that these effects are at least partly due to a non-genomic action of the steroid at the oocyte surface. Here we provide evidence showing that a non-genomic effect of oestradiol is counteracted by androstenedione. In contrast to these results from in-vitro experiments, in which changes in steroid concentrations are abrupt and the non-genomic responses are rapid, the progressively changing follicular steroid concentrations which occur during in-vivo development may rather have permissive or restrictive effects on the events of spontaneous oocyte cytoplasmic maturation. The oocyte is particularly sensitive at the germinal vesicle stage of development to non-genomic steroid actions. Ovarian stimulation protocols should thus be adjusted so as to avoid androgen predominance at the mid-follicular phase. In patients in whom this condition cannot be met, in-vitro maturation of oocytes may be a solution.


Asunto(s)
Andrógenos/farmacología , Estrógenos/farmacología , Oocitos/efectos de los fármacos , Oocitos/fisiología , Androstenodiona/farmacología , Calcio/metabolismo , Estradiol/farmacología , Femenino , Humanos
20.
Baillieres Clin Obstet Gynaecol ; 11(4): 763-72, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9692016

RESUMEN

Both animal experimentation data and preliminary clinical experience converge to suggest that normal progeny can be obtained by fertilizing oocytes with spermatids, the youngest male germ cells to have a set of haploid chromosomes. Spermatids can be obtained from the ejaculate of many patients with non-obstructive azoospermia. The use of ejaculated spermatids in the treatment of non-obstructive azoospermia is thus to be considered as an alternative to that of testicular spermatozoa. Fertilization with ejaculated spermatids makes it possible to avoid the potential adverse consequences of extensive testicular biopsy and may thus become the treatment of first choice. The recourse to testicular spermatids represents a treatment of last chance if no spermatids can be recovered either from the ejaculate and no spermatozoa from the testis.


Asunto(s)
Inseminación Artificial Homóloga/métodos , Oligospermia/terapia , Espermátides/trasplante , Eyaculación , Humanos , Masculino , Microinyecciones/métodos , Testículo
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