RESUMO
Vasectomy reversal involves either vasovasostomy (VV) or epididymovasostomy (EV), and rates of epididymal obstruction and EV increase with time after vasectomy. However, as older vasectomies may not require EV for successful reversal, we hypothesized that sperm production falls after vasectomy and can protect the system from epididymal blowout. Our objective was to define how the need for EV at reversal changes with time after vasectomy through a retrospective review of consecutive reversals performed by three surgeons over a 10-year period. Vasovasotomy was performed with Silber score 1-3 vasal fluid. EVs were performed with Silber score 4 (sperm fragments; creamy fluid) or 5 (sperm absence) fluid. Reversal procedure type was correlated with vasectomy and patient age. Post-operative patency rates, total spermatozoa and motile sperm counts in younger (<15 years) and older (>15 years) vasectomies were assessed. Simple descriptive statistics determined outcome relevance. Among 1229 patients, 406 had either unilateral (n = 252) or bilateral EV's (n = 154) constituting 33% (406/1229) of reversals. Mean patient age was 41.4±7 years (range 22-72). Median vasectomy interval was 10 years (range 1-38). Overall sperm patency rate after reversal was 84%. The rate of unilateral (EV/VV) or bilateral EV increased linearly in vasectomy intervals of 1-22 years at 3% per year, but plateaued at 72% in vasectomy intervals of 24-38 years. Sperm counts were maintained with increasing time after vasectomy, but motile sperm counts decreased significantly (p < 0.001). Pregnancy, secondary azoospermia, varicocoele and sperm granuloma were not assessed. In conclusion, and contrary to conventional thinking, the need for EV at reversal increases with time after vasectomy, but this relationship is not linear. EV rates plateau 22 years after vasectomy, suggesting that protective mechanisms ameliorate epididymal 'blowout'. Upon reversal, sperm output is maintained with time after vasectomy, but motile sperm counts decrease linearly, suggesting epididymal dysfunction influences semen quality after reversal.
Assuntos
Epididimo/cirurgia , Ducto Deferente/cirurgia , Vasovasostomia/métodos , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/citologia , Vasectomia , Adulto JovemAssuntos
Transplante de Medula Óssea , Fertilização in vitro/métodos , Neoplasias Hematológicas/terapia , Infertilidade Masculina/terapia , Paternidade , Adulto , Feminino , Neoplasias Hematológicas/complicações , Humanos , Infertilidade Masculina/etiologia , Masculino , Gravidez , Resultado da Gravidez , Espermatozoides , Testículo/citologiaRESUMO
It is widely thought that human testicles affected by unilateral pathology will have greater impairment of spermatogenesis than the otherwise unaffected testis. This study reviewed records of non-obstructive azoospermic (NOA) and virtually azoospermic (NOVA) men with associated testicular pathology who underwent testicular fine needle aspiration (FNA) mapping. Concentration of spermatozoa found in each testis was analysed to discern sperm-lateralization patterns in affected and unaffected testes. A total of 1098 FNA sites from 56 men (32 varicocele, 16 cryptorchidism, three epididymo-orchitis, two mumps orchitis, three torsion) were analysed. Overall, 38 patients (68%) had spermatozoa detected in at least one testis. Most men (68%) had equal proportions of FNA sites showing spermatozoa from both testes, 29% had more spermatozoa from the unaffected testis and 3% had more spermatozoa from the affected testis. Significantly fewer sperm-positive sites were observed on the affected (272 out of 752) than unaffected side (164 out of 346) (P < 0.0001, chi-squared test). When assessed by FNA mapping, most NOA and NOVA men with known unilateral testis pathology will have equal proportions of spermatozoa in both testes. However, when sperm production differs between sides, the unaffected side is much more likely to have spermatozoa. This information may be used to refine sperm-retrieval strategies in selected patients.
Assuntos
Azoospermia/fisiopatologia , Espermatogênese/fisiologia , Espermatozoides/citologia , Testículo/patologia , Adulto , Azoospermia/etiologia , Biópsia por Agulha Fina/métodos , Humanos , Masculino , Espermatozoides/fisiologia , Testículo/cirurgiaRESUMO
PURPOSE: Currently it is thought to take 60 to 70 days to produce and ejaculate human sperm. This estimate is derived mainly from a single older, descriptive, kinetic analysis of spermatogenesis. We developed a noninvasive method to assess germ cell turnover time accurately in vivo using stable isotope labeling and gas chromatography/mass spectrometry analyses. We confirmed the postulated length of a normal cycle of spermatogenesis. MATERIALS AND METHODS: A total of 11 men with normal sperm concentrations ingested (2)H(2)O daily for 3 weeks. Semen samples were collected every 2 weeks for up to 90 days. Label incorporation into sperm DNA was quantified by gas chromatography/mass spectrometry, allowing calculation of the percent of new cells present. A cycle of sperm production was determined as the lag time until labeled sperm appeared in the ejaculate. RESULTS: Labeled sperm were detected after a mean +/- SD of 64 +/- 8 days (range 42 to 76). In 1 subject the time lag was 42 days but it was at least 60 in all other subjects. In most subjects plateau labeling in sperm was not attained. In 2 subjects the rise and fall of the labeling curve was steep and reached greater than 85% new cells, suggesting rapid washout of old sperm in the epididymal reservoir. CONCLUSIONS: This direct kinetic assessment confirms a course of spermatogenesis that is on the shorter side of traditional estimates based on prior analyses. In addition, the variability observed in healthy men suggests that characteristics such as the epididymal reservoir effect may influence the modeling of in vivo spermatogenesis.
Assuntos
Espermatogênese , Espermatozoides/diagnóstico por imagem , Adulto , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Cintilografia , Fatores de TempoRESUMO
The molecular cause of germ cell meiotic defects in azoospermic men is rarely known. During meiotic prophase I, a proteinaceous structure called the synaptonemal complex (SC) appears along the pairing axis of homologous chromosomes and meiotic recombination takes place. Newly-developed immunofluorescence techniques for SC proteins (SCP1 and SCP3) and for a DNA mismatch repair protein (MLH1) present in late recombination nodules allow simultaneous analysis of synapsis, and of meiotic recombination, during the first meiotic prophase in spermatocytes. This immunofluorescent SC analysis enables accurate meiotic prophase substaging and the identification of asynaptic pachytene spermatocytes. Spermatogenic defects were examined in azoospermic men using immunofluorescent SC and MLH1 analysis. Five males with obstructive azoospermia, 18 males with nonobstructive azoospermia and 11 control males with normal spermatogenesis were recruited for the study. In males with obstructive azoospermia, the fidelity of chromosome pairing (determined by the percentage of cells with gaps [discontinuities]/splits [unpaired chromosome regions] in the SCs, and nonexchange SCs [bivalents with 0 MLH1 foci]) was similar to those in normal males. The recombination frequencies (determined by the mean number of MLH1 foci per cell at the pachytene stage) were significantly reduced in obstructive azoospermia compared to that in controls. In men with nonobstructive azoospermia, a marked heterogeneity in spermatogenesis was found: 45% had a complete absence of meiotic cells; 5% had germ cells arrested at the zygotene stage of meiotic prophase; the rest had impaired fidelity of chromosome synapsis and significantly reduced recombination in pachytene. In addition, significantly more cells were in the leptotene and zygotene meiotic prophase stages in nonobstructive azoospermic patients, compared to controls. Defects in chromosome pairing and decreased recombination during meiotic prophase may have led to spermatogenesis arrest and contributed in part to this unexplained infertility.
Assuntos
Oligospermia/genética , Complexo Sinaptonêmico/genética , Humanos , Masculino , Meiose , Recombinação Genética , Valores de Referência , Complexo Sinaptonêmico/patologia , Complexo Sinaptonêmico/ultraestruturaRESUMO
To date, immunocytology has been used in humans to detect a limited number of meiotic proteins: components of the synaptonemal complex (SCP1 and SCP3) and some proteins known to participate in recombination events, such as MLH1 or RAD51. However, the colocalization or coexistence of proteins known to participate during the different stages of human meiosis remains largely unstudied, and these studies could provide important clues about the mechanics of recombination. This work reports the relative timing and localization of five different meiotic proteins that have previously been implicated in human homologous recombination [RAD51, replication protein A (RPA), MSH4, MLH1 and MLH3]. MSH4 foci appear concurrently with synapsis initiation at zygotene, shortly after the first RAD51 foci are detected. The presence of RPA in MSH4 foci was noted, suggesting that these two proteins may act co-operatively. Both RPA and MSH4 foci reach maximal numbers at the end of zygotene, when synapsis is concluding. From this point, RPA foci all but disappear by the end of pachytene, whereas MSH4 foci decline to a stable number at mid-pachytene, where they localize with MLH1/MLH3 recombination sites. We discuss a possible role for MSH4 in synapsis initiation and/or maintenance.
Assuntos
Recombinação Genética/fisiologia , Testículo/fisiologia , Proteínas de Transporte/genética , Proteínas de Ciclo Celular/genética , Humanos , Masculino , Meiose/genética , Proteínas MutL , Prófase/genéticaRESUMO
A reciprocal translocation between the long arm of the Y chromosome and the long arm of chromosome 1 was observed in an infertile man with non-obstructive azoospermia. The study was performed using a combination of techniques: immunocytogenetic analysis, which allows the detection of synaptonemal complexes (SCs) and recombination sites (MLH1) simultaneously, and fluorescence in-situ hybridization analysis. Meiotic pairing analysis on 100 pachytene spreads showed the presence of a quadrivalent containing chromosomes 1 and Y. There were many abnormalities in chromosome pairing and recombination. These abnormalities included a great reduction of recombination events (as many as one fifth of the SCs had no MLH1 foci), and high proportions of unpaired regions and discontinuities in the SCs. We discuss the possibility that infertility in this patient may be due to transcriptional repression of part of chromosome 1 involved in the translocation, silencing some genes necessary for the progression of meiosis and causing defective meiotic pairing and recombination.
Assuntos
Cromossomos Humanos Par 1/genética , Cromossomos Humanos Y/genética , Meiose/genética , Oligospermia/genética , Translocação Genética , Adulto , Pareamento Cromossômico , Inativação Gênica , Humanos , Masculino , Recombinação GenéticaRESUMO
A deficiency of dietary selenium leads to immotile, deformed sperm and infertility in rats, whereas supplementation of the diet with selenium compounds has been associated with both beneficial and deleterious effects on sperm function, depending on the chemical form of selenium. We conducted a randomized, controlled, and blinded intervention study on the effects of selenium in food on semen quality. Eleven healthy men were fed a controlled diet of foods naturally high or low in selenium for 120 days while confined in a metabolic research unit. Dietary selenium was 47 microg/d for the first 21 days, then either 13 microg/d or 297 microg/d for 99 days, resulting in significant changes in selenium concentrations in blood and semen. Seminal plasma selenium concentration increased 50% with high selenium and decreased 40% with low selenium. The fraction of motile sperm in the high-selenium group decreased by 32% by week 13 and ended 18% lower than baseline. Selenium concentrations changed in seminal plasma but not in sperm, and serum androgen concentrations were unchanged in both groups, indicating this effect was neither androgen dependent nor caused by a change in the selenium supply to the testes. Serum triiodothyronine decreased and thyroid-stimulating hormone increased in the high-selenium group, suggesting that altered thyroid hormone metabolism may have affected sperm motility. Although this decrease in sperm motility does not necessarily predict decreased fertility, the increasing frequency of selenium supplementation in the healthy population suggests the need for larger studies to more fully assess this potential side effect.
Assuntos
Suplementos Nutricionais , Selênio/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Hormônios Esteroides Gonadais/sangue , Humanos , Masculino , Hormônios Hipofisários/sangue , Valores de Referência , Selênio/análise , Selênio/sangue , Sêmen , Tri-Iodotironina/sangueRESUMO
OBJECTIVE: To describe two cases of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) with testicular sperm in men with immotile cilia syndromes. DESIGN: Case report. SETTING: A university-based male infertility clinic and assisted reproduction unit. PATIENT(S): Two couples with male factor infertility due to Kartagener/immotile cilia syndrome. INTERVENTION(S): IVF/ICSI with testicular sperm. MAIN OUTCOME MEASURE(S): Semen characteristics, sperm viability, fertilization rate, and pregnancy. RESULT(S): With testicular sperm, the two pronuclear fertilization rates were 63% and 60% in two cases. One case resulted in the birth of normal healthy girl. CONCLUSION(S): With testicular sperm, successful oocyte fertilization after ICSI in couples with male Kartagener/immotile cilia syndrome is possible despite the lack of sperm motility.
Assuntos
Transtornos da Motilidade Ciliar/fisiopatologia , Síndrome de Kartagener/fisiopatologia , Injeções de Esperma Intracitoplásmicas , Espermatozoides/fisiologia , Testículo , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez , Contagem de Espermatozoides , Motilidade dos EspermatozoidesRESUMO
OBJECTIVE: To describe the pathology-specific response to transurethral resection of ejaculatory ducts (TURED) in patients with complete or partial ejaculatory duct obstruction and to evaluate the role of TURED in light of powerful assisted reproductive technologies. DESIGN: Retrospective clinical study. SETTING: University hospital. PATIENT(S): Thirty-eight infertile men with obstruction of the ejaculatory ducts. INTERVENTION(S): Diagnosis by transrectal ultrasonography or magnetic resonance imaging, and treatment with TURED. MAIN OUTCOME MEASURE(S): Changes in semen variables, pregnancy outcomes, and complication rates were analyzed before and after surgery. RESULT(S): Improvement in semen variables was significantly better in patients with partial obstruction (94%) of ducts than in those with complete obstruction (59%) (P=.04). Cystic obstruction, especially midline and eccentric cysts, responded best to TURED. Before surgery, all patients were candidates for IVF/ICSI; after surgery, 32% of azoospermic men and 81% of oligospermic men conceived spontaneously or were referred for IUI instead of IVF/ICSI. CONCLUSION(S): Ejaculatory duct obstruction due to cysts appears to respond best to TURED. In addition, TURED may decrease the need for IVF/ICSI as primary treatment in many cases. Finally, TURED may allow IVF/ICSI to be performed with ejaculated rather than surgically retrieved sperm.
Assuntos
Ductos Ejaculatórios/cirurgia , Infertilidade Masculina/cirurgia , Adulto , Constrição Patológica/diagnóstico , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Cistos/complicações , Cistos/cirurgia , Ductos Ejaculatórios/diagnóstico por imagem , Ductos Ejaculatórios/patologia , Feminino , Fertilização in vitro , Doenças dos Genitais Masculinos/complicações , Doenças dos Genitais Masculinos/cirurgia , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas , Ultrassonografia , Uretra/cirurgiaRESUMO
The sequence of events encompassing ejaculation has been well described. Multiple disease processes can result in ejaculatory dysfunction. Evaluation and subsequent treatment of ejaculatory dysfunction is possible using behavioral, mechanical, and medical and surgical modalities. Further elucidation of ejaculation is now taking place at the molecular level.
Assuntos
Ejaculação/fisiologia , Disfunções Sexuais Fisiológicas/fisiopatologia , Humanos , Masculino , Prostatectomia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Disfunções Sexuais Fisiológicas/psicologia , Disfunções Sexuais Fisiológicas/terapiaRESUMO
OBJECTIVES: To compare the clinical characteristics of infertile men who have varicocele with and without a genetic anomaly, and report the results of varicocelectomy in these two cohorts of men. METHODS: Study subjects included 33 men who underwent genetic counseling and testing for a diagnosis of oligospermia with varicocele. Seven men were diagnosed with coexisting genetic infertility (genetic [+]; abnormal karyotype in 4, Y chromosome microdeletion in 3), and 26 men with varicocele and no genetic abnormality (genetic [-]). Five patients (Y chromosome microdeletions in 2, abnormal karyotype in 3) in the genetic (+) group and 14 patients in the genetic (-) group underwent microsurgical subinguinal varicocelectomy. Semen and hormonal parameters, physical examination findings, as well as the response to varicocele repair were compared between the two groups. Varicocele response was defined as a 50% increase in total motile sperm count in the ejaculate. RESULTS: Mean preoperative seminal and hormonal parameters were not statistically significantly different between the two groups. Significant differences were observed in the volume of the right and left testicles between the two groups (left: P = 0.007; right: P = 0.04). Although 7 of 13 evaluable patients (54%) in the genetic (-) group had a seminal response to varicocelectomy, none of 5 patients in the genetic (+) group showed improvement in semen quality. CONCLUSIONS: From this early experience, men with varicocele and genetic lesions appear to have a poorer response to varicocele repair than men without coexisting genetic lesions. These data may have implications for counseling male factor infertility patients contemplating varicocele treatment.
Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Oligospermia/etiologia , Varicocele/complicações , Varicocele/cirurgia , Adulto , Seguimentos , Aconselhamento Genético , Humanos , Cariotipagem , Masculino , Oligospermia/genética , Exame Físico , Valores de Referência , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Testículo/anatomia & histologia , Testosterona/sangueRESUMO
The published experience with frozen-thawed epididymal spermatozoa and intracytoplasmic sperm injection (ICSI) suggests that fertilization and pregnancy success rates are comparable to those achieved with freshly retrieved spermatozoa. However, no study has exactly compared clinical outcomes between the two IVF/ICSI cycles in the same couples. To formally address this issue, we assessed ICSI outcomes in couples each of whom had had two IVF/ICSI cycles: one using fresh and the second using frozen-thawed epididymal spermatozoa obtained from a single aspiration procedure. From a pool of 101 consecutive patients undergoing IVF/ICSI with epididymal spermatozoa, 19 couples initially used fresh epididymal spermatozoa and subsequently underwent a second IVF/ICSI procedure with frozen-thawed spermatozoa from the same aspiration. Normal (2PN) oocyte fertilization rates, embryo quality and pregnancy rates were compared between the two IVF/ICSI cycles for each couple. In the fresh epididymal sperm group, 58.4% of the injected oocytes fertilized normally compared with 62.0% of the injected oocytes in the frozen-thawed epididymal sperm group, revealing no statistically significant difference. Graded embryo quality also did not differ significantly between the paired IVF/ICSI cycles. The clinical pregnancy rates were 31.6% (6/19) and 36.8% (7/19) in the first and second cycles respectively. All but one pregnancy were singletons. In summary, this study provides strong evidence to support the notion that motile, cryopreserved and thawed epididymal spermatozoa are equal to freshly retrieved spermatozoa for ICSI in couples with obstructive azoospermia.
Assuntos
Criopreservação , Epididimo , Injeções de Esperma Intracitoplásmicas , Espermatozoides/fisiologia , Embrião de Mamíferos/fisiologia , Feminino , Fertilização , Fertilização in vitro , Humanos , Masculino , Oócitos/fisiologia , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Resultado do TratamentoRESUMO
It is generally assumed that men with congenital bilateral absence of the vas deferens (CBAVD) have azoospermia because of obstruction and that sperm production is normal. This study examines spermatogenesis in men with CBAVD to assess the validity of this assumption. We identified all men with CBAVD who had undergone either a diagnostic or therapeutic fertility procedure. Procedures included diagnostic biopsy, testis fine needle aspiration (FNA) mapping, microscopic epididymal sperm aspiration (MESA), and testis sperm extraction (TESE). Among 33 CBAVD men, 18 underwent testis biopsy, 27 had MESA/TESE, and 10 had FNA mapping. On evaluation of these procedures, normal spermatogenesis was present in 29 men. Four men (12%) demonstrated impaired spermatogenesis. One patient had FNA testis cytology consistent with late maturation arrest, another demonstrated hypospermatogenesis on biopsy and low sperm yield by MESA, and two patients had pure Sertoli cell only histology on biopsy. Aetiologies for impaired spermatogenesis included varicocele and underlying genetic abnormalities. Although patients with CBAVD are assumed to have normal spermatogenesis and infertility due simply to obstruction, the potential for concomitant defects in sperm production exists. A clinical suspicion of testis failure should prompt further diagnostic evaluation of spermatogenesis prior to sperm retrieval. In addition, genetic counselling should be offered and testing for genetic lesions, including cystic fibrosis gene mutations and/or variants, Y chromosome microdeletions, and karyotype abnormalities, should be considered.
Assuntos
Espermatogênese , Ducto Deferente/anormalidades , Adulto , Biópsia , Senescência Celular , Humanos , Infertilidade Masculina/complicações , Infertilidade Masculina/etiologia , Masculino , Pessoa de Meia-Idade , Células de Sertoli/patologia , Contagem de Espermatozoides , Doenças Testiculares/complicações , Testículo/patologia , Varicocele/complicaçõesRESUMO
Open testicular biopsy is the standard method for histopathologic assessment of spermatogenesis. The need for testis biopsy has been questioned with the increased success of minimally invasive techniques such as fine-needle aspiration (FNA) mapping. This study examines whether FNA can provide cytologic information equivalent to histologic patterns by correlating diagnoses from testis FNA cytology with biopsy histology. Men (n = 87) who had undergone both diagnostic FNA mapping and open testis biopsy in the evaluation of infertility were identified. Biopsies were assessed by recognized histologic patterns of normal, hypospermatogenesis, early and late maturation arrest, and Sertoli cell only. FNA cytologic specimens were examined for adequacy and were classified similarly. Mixed patterns were also identified. The correlation between the two methods was 94%, with no differences among the different histologies. Discrepancies between cytology and histology were primarily the result of inadequate sampling and evidence of mixed patterns on FNA mapping. FNA cytology is a minimally invasive method of obtaining testicular tissue for diagnostic purposes. These data demonstrate that FNA cytology can evaluate accurately all classically defined histologic types, and may have the potential to replace testis biopsy in the assessment of spermatogenesis.
Assuntos
Biópsia por Agulha , Infertilidade Masculina/patologia , Oligospermia/patologia , Espermatogênese , Testículo/patologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
Systematic testis fine needle aspiration (FNA) mapping has been proposed as an adjunctive or alternative diagnostic procedure to biopsy to determine the presence of spermatozoa within infertile testes. This study related testis histology to the global presence or absence of spermatozoa in the same testes determined by FNA cytology. Testis biopsies and FNA mapping were performed in 87 infertile, azoospermic men. A mean of 1.3 biopsies and 14 FNA sites were taken per patient. Biopsies were assessed by recognized histological patterns of normal, Sertoli cell-only, hypospermatogenesis, early and late maturation arrest, sclerosis as well as mixed patterns that included at least two of these histologies. FNA cytological specimens were assessed for sperm presence by an experienced cytologist. Overall, spermatozoa were found by FNA mapping in 52% of patients. A comparison of histology and FNA findings revealed that pure patterns of Sertoli cell-only and early maturation were associated with a very poor likelihood of sperm detection (4-8%). In contrast, patients with other pure pattern histologies or mixed patterns had high rates of FNA sperm detection (77-100%). Similar to reported testicular sperm extraction (TESE) findings, sperm detection with FNA shows wide variation depending on testis histology. Unlike most TESE reports, however, some histological patterns generally reflect a more global testicular dysfunction and poorer likelihood of sperm identification, suggesting the possibility that these phenotypes have a genetic origin. Systematic testis sampling with FNA offers additional geographical information about spermatogenesis that routine biopsies lack and can further guide couple decision-making in severe male factor infertility.
Assuntos
Biópsia por Agulha , Infertilidade Masculina/patologia , Espermatozoides/patologia , Testículo/patologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Oligospermia/patologia , Células de Sertoli/patologia , EspermatogêneseRESUMO
In diverse organisms from yeast to mice, mutations in numerous genes required for DNA repair may lead to defects in meiosis. Although it is likely that meiosis is conserved throughout evolution, little is known about the genetics of meiosis in humans even though meiotic arrest associated with azoospermia is common. In this work, we compared the sequence fidelity of a polymorphic marker amplified from DNA of two groups of patients: those with testis biopsy suggesting meiotic arrest and those with normal spermatogenesis who were obstructed. We demonstrated that mutations are more common in DNA from testicular tissue derived from men with meiotic arrest than in DNA from testicular tissue derived from men with normal spermatogenesis and physical obstruction (P < 0.05). No mutations were observed in blood tissue from either group of men. This suggests the possibility that defects in genes required in DNA repair could contribute to meiotic arrest in men just as has been observed in other organisms.
Assuntos
DNA/genética , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Meiose , Mutação Puntual/genética , Testículo/patologia , Sequência de Bases/genética , Constrição Patológica , Reparo do DNA , Feminino , Frequência do Gene , Doenças dos Genitais Masculinos/complicações , Doenças dos Genitais Masculinos/genética , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/patologia , Masculino , Dados de Sequência Molecular , Valores de Referência , EspermatogêneseRESUMO
PURPOSE: Although helpful for defining extratesticular obstruction, the testis biopsy offers limited information on nonobstructive azoospermic testes. Guided by diagnostic biopsies, testis sperm extraction procedures fail in 25% to 50% of patients with nonobstructive azoospermia, largely because it is clinically difficult to know where sperm are located. To provide a more complete assessment of spermatogenesis in nonobstructive azoospermic patients and to simplify the confirmation of sperm production in men with obstruction, we use a systematic, fine needle aspiration "mapping" procedure. We summarize the diagnostic findings in a series of azoospermic men. MATERIALS AND METHODS: From 118 azoospermic infertile men (22 with obstructed and 96 with nonobstructed azoospermia) fine needle aspiration data were used to generate location specific, sperm frequency maps for obstructed and nonobstructive azoospermic testes to determine if "sperm rich" locations existed. RESULTS: Fine needle aspiration map analysis revealed that all aspiration locations from obstructed cases showed sperm. In men with nonobstructive azoospermia, sperm was identified in the right testis in 134 of 652 (20.5%) and in the left testis in 151 of 716 (21.1%) separate aspirations. Rates of sperm detection among various intratesticular sites were not statistically different. In 27.1% of cases the fine needle aspiration map found sperm in men with sperm negative biopsies. The likelihood of heterogeneity in fine needle aspiration sperm findings was 25% within individual nonobstructive azoospermic testes and 19.2% between testis sides. At post-procedure followup of 88 patients (74%), no clinical or surgical complications were observed. CONCLUSIONS: Testis fine needle aspiration mapping is a simple, reliable and informative diagnostic tool in the evaluation of azoospermic infertile men.
Assuntos
Oligospermia/patologia , Oligospermia/fisiopatologia , Espermatogênese , Testículo/patologia , Biópsia por Agulha , Humanos , Masculino , Oligospermia/etiologiaRESUMO
A 40 year old healthy Chinese male with primary infertility was seen in a university male infertility and genetic counselling clinic. He presented with congenital bilateral absence of the vas deferens (CBAVD) and the finding of testis atrophy. Fine needle aspiration mapping of the testis identified and localized sperm production within the testicles for in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Careful evaluation of testicular cytology revealed late maturation arrest of spermatogenesis. Cystic fibrosis gene mutation analysis revealed heterozygosity for the 5T variant within the polypyrimidine tract of intron 8. Cytogenetic analysis revealed a pericentric inversion of chromosome 6 with break points at p12 and q21 [46,XY,inv(6)(p12q21)]. This case illustrates that spermatogenesis is not necessarily normal with congenital bilateral absence of the vas deferens. Compound genetic defects may coexist and underlie male infertility.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Infertilidade Masculina/genética , Ducto Deferente/anormalidades , Adulto , Alelos , Inversão Cromossômica , Cromossomos Humanos Par 6 , Humanos , Cariotipagem , Masculino , Mutação , Oligospermia/genética , Injeções de Esperma Intracitoplásmicas , Espermatozoides/citologia , Testículo/patologiaRESUMO
Infertile men with severe spermatogenic defects and low or no sperm counts have a significantly higher rate of genetic abnormalities than fertile men. The fact that intracytoplasmic sperm injection can potentially bypass natural selection barriers to genetic disease transmission has brought a sobering but important impetus to recent research in the area of genetic infertility. Recent studies have focused on examining the prevalence of certain genetic defects in infertile men, analyzing the molecular basis of infertility in genetic disorders, and detecting new causes of genetic infertility. Several novel research findings deserve mention for their potential impact on genetic infertility. It has been demonstrated that elongated and round spermatids can be successfully injected into human oocytes and viable births obtained. Likewise, significant advances have been made in the arena of interspecies germ cell transplantation. Of some concern is the finding of a relationship between faulty DNA repair and infertility in men with severe testis failure. This review summarizes the recent genetic advances in these areas of male genetic infertility.