Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
Hum Reprod ; 36(9): 2597-2611, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34089056

RESUMEN

STUDY QUESTION: What are the causative genetic variants in patients with male infertility due to severe sperm motility disorders? SUMMARY ANSWER: We identified high confidence disease-causing variants in multiple genes previously associated with severe sperm motility disorders in 10 out of 21 patients (48%) and variants in novel candidate genes in seven additional patients (33%). WHAT IS KNOWN ALREADY: Severe sperm motility disorders are a form of male infertility characterised by immotile sperm often in combination with a spectrum of structural abnormalities of the sperm flagellum that do not affect viability. Currently, depending on the clinical sub-categorisation, up to 50% of causality in patients with severe sperm motility disorders can be explained by pathogenic variants in at least 22 genes. STUDY DESIGN, SIZE, DURATION: We performed exome sequencing in 21 patients with severe sperm motility disorders from two different clinics. PARTICIPANTS/MATERIALS, SETTING, METHOD: Two groups of infertile men, one from Argentina (n = 9) and one from Australia (n = 12), with clinically defined severe sperm motility disorders (motility <5%) and normal morphology values of 0-4%, were included. All patients in the Argentine cohort were diagnosed with DFS-MMAF, based on light and transmission electron microscopy. Sperm ultrastructural information was not available for the Australian cohort. Exome sequencing was performed in all 21 patients and variants with an allele frequency of <1% in the gnomAD population were prioritised and interpreted. MAIN RESULTS AND ROLE OF CHANCE: In 10 of 21 patients (48%), we identified pathogenic variants in known sperm assembly genes: CFAP43 (3 patients); CFAP44 (2 patients), CFAP58 (1 patient), QRICH2 (2 patients), DNAH1 (1 patient) and DNAH6 (1 patient). The diagnostic rate did not differ markedly between the Argentinian and the Australian cohort (55% and 42%, respectively). Furthermore, we identified patients with variants in the novel human candidate sperm motility genes: DNAH12, DRC1, MDC1, PACRG, SSPL2C and TPTE2. One patient presented with variants in four candidate genes and it remains unclear which variants were responsible for the severe sperm motility defect in this patient. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In this study, we described patients with either a homozygous or two heterozygous candidate pathogenic variants in genes linked to sperm motility disorders. Due to unavailability of parental DNA, we have not assessed the frequency of de novo or maternally inherited dominant variants and could not determine the parental origin of the mutations to establish in all cases that the mutations are present on both alleles. WIDER IMPLICATIONS OF THE FINDINGS: Our results confirm the likely causal role of variants in six known genes for sperm motility and we demonstrate that exome sequencing is an effective method to diagnose patients with severe sperm motility disorders (10/21 diagnosed; 48%). Furthermore, our analysis revealed six novel candidate genes for severe sperm motility disorders. Genome-wide sequencing of additional patient cohorts and re-analysis of exome data of currently unsolved cases may reveal additional variants in these novel candidate genes. STUDY FUNDING/COMPETING INTEREST(S): This project was supported in part by funding from the Australian National Health and Medical Research Council (APP1120356) to M.K.O.B., J.A.V. and R.I.M.L., The Netherlands Organisation for Scientific Research (918-15-667) to J.A.V., the Royal Society and Wolfson Foundation (WM160091) to J.A.V., as well as an Investigator Award in Science from the Wellcome Trust (209451) to J.A.V. and Grants from the National Research Council of Argentina (PIP 0900 and 4584) and ANPCyT (PICT 9591) to H.E.C. and a UUKi Rutherford Fund Fellowship awarded to B.J.H.


Asunto(s)
Exoma , Infertilidad Masculina , Australia , Humanos , Infertilidad Masculina/genética , Masculino , Motilidad Espermática/genética , Cola del Espermatozoide , Espermatozoides , Secuenciación del Exoma
2.
Hum Reprod ; 35(1): 240-252, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31985809

RESUMEN

STUDY QUESTION: Can exome sequencing identify new genetic causes of globozoospermia? SUMMARY ANSWER: Exome sequencing in 15 cases of unexplained globozoospermia revealed deleterious mutations in seven new genes, of which two have been validated as causing globozoospermia when knocked out in mouse models. WHAT IS KNOWN ALREADY: Globozoospermia is a rare form of male infertility characterised by round-headed sperm and malformation of the acrosome. Although pathogenic variants in DPY19L2 and SPATA16 are known causes of globozoospermia and explain up to 70% of all cases, genetic causality remains unexplained in the remaining patients. STUDY DESIGN, SIZE, DURATION: After pre-screening 16 men for mutations in known globozoospermia genes DPY19L2 and SPATA16, exome sequencing was performed in 15 males with globozoospermia or acrosomal hypoplasia of unknown aetiology. PARTICIPANTS/MATERIALS, SETTING, METHOD: Targeted next-generation sequencing and Sanger sequencing was performed for all 16 patients to screen for single-nucleotide variants and copy number variations in DPY19L2 and SPATA16. After exclusion of one patient with DPY19L2 mutations, we performed exome sequencing for the 15 remaining subjects. We prioritised recessive and X-linked protein-altering variants with an allele frequency of <0.5% in the population database GnomAD in genes with an enhanced expression in the testis. All identified candidate variants were confirmed in patients and, where possible, in family members using Sanger sequencing. Ultrastructural examination of semen from one of the patients allowed for a precise phenotypic characterisation of abnormal spermatozoa. MAIN RESULTS AND ROLE OF CHANCE: After prioritisation and validation, we identified possibly causative variants in eight of 15 patients investigated by exome sequencing. The analysis revealed homozygous nonsense mutations in ZPBP and CCDC62 in two unrelated patients, as well as rare missense mutations in C2CD6 (also known as ALS2CR11), CCIN, C7orf61 and DHNA17 and a frameshift mutation in GGN in six other patients. All variants identified through exome sequencing, except for the variants in DNAH17, were located in a region of homozygosity. Familial segregation of the nonsense variant in ZPBP revealed two fertile brothers and the patient's mother to be heterozygous carriers. Paternal DNA was unavailable. Immunohistochemistry confirmed that ZPBP localises to the acrosome in human spermatozoa. Ultrastructural analysis of spermatozoa in the patient with the C7orf61 mutation revealed a mixture of round heads with no acrosomes (globozoospermia) and ovoid or irregular heads with small acrosomes frequently detached from the sperm head (acrosomal hypoplasia). LIMITATIONS, REASONS FOR CAUTION: Stringent filtering criteria were used in the exome data analysis which could result in possible pathogenic variants remaining undetected. Additionally, functional follow-up is needed for several candidate genes to confirm the impact of these mutations on normal spermatogenesis. WIDER IMPLICATIONS OF THE FINDINGS: Our study revealed an important role for mutations in ZPBP and CCDC62 in human globozoospermia as well as five new candidate genes. These findings provide a more comprehensive understanding of the genetics of male infertility and bring us closer to a complete molecular diagnosis for globozoospermia patients which would help to predict the success of reproductive treatments. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Netherlands Organisation for Scientific Research (918-15-667); National Health and Medical Research Council of Australia (APP1120356) and the National Council for Scientific Research (CONICET), Argentina, PIP grant 11220120100279CO. The authors have nothing to disclose.


Asunto(s)
Infertilidad Masculina , Teratozoospermia , Australia , Variaciones en el Número de Copia de ADN , Exoma , Humanos , Infertilidad Masculina/genética , Masculino , Proteínas de la Membrana/genética , Países Bajos , Espermatozoides , Teratozoospermia/genética
3.
Andrology ; 3(1): 59-69, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25598272

RESUMEN

All malignant testicular germ cell tumors (TGCT) of adult men are preceded by an in situ stage (CIS) of protracted evolution. The adult CIS is well characterized, but there is debate on the phenotype of infantile CIS, its distinction from delayed maturation of germ cells and prognostic potential. A large series of 43 patients with Disorders of Sex Development (DSD) and dysgenetic testes (90% ranging from neonates to 12 years, mean age 4.7 years), was studied by quantifying dysgenetic features, degree of germ cell abnormalities/atypia (GCA), expression of OCT 3/4 (a pluripotency-undifferentiation marker), germ cell ploidy and evolution to CIS and invasive TGCT. Findings were compared with those of normal testes. The type of gonads present defined three groups of patients: bilateral testes (BT-DSD, n = 21), one testis and one streak gonad (CT-DSD, C for combined, n = 13), and ovarian-testicular combinations (OT-DSD, n = 9). There were 5 boys with infantile CIS, bilateral in 3 (total of 8 infantile CIS) and two patients with adult CIS, bilateral in one (total of 3 adult CIS). Two patients had bilateral seminomas one at 12-17 and the other at 23 years. Histological dysgenesis was significantly higher in CT-DSD (p < 0.05), that had only 1 CIS. The highest frequency of GCA was in BT-DSD (p < 0.05), which coincided with a total of 11CIS + Seminomas. In all patients, aneuploidy was significantly higher (63%) than diploidy (p < 0.02), and GCA were more frequent in aneuploid than in diploid samples (p < 0.02). All CIS and TGCT were OCT 3/4 positive. Finally, there was a significant association between the triad Aneuploidy + GCA + OCT 3/4 positivity and the incidence of CIS (Fisher Exact test p < 0.002, relative risk 7.0). The degree of testicular dysgenesis (derived from abnormal organization of Sertoli cells in fetal testicular cords) is inversely related to the incidence of CIS. Our data demonstrate that the combined use of OCT 3/4 expression, quantification of germ cell abnormalities-atypia and ploidy in dysgenetic testes can satisfactorily identify infantile CIS with high risk of malignant evolution and set it aside from delayed germ cell maturation with lower or nil neoplastic potential.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma in Situ/genética , Disgenesia Gonadal/genética , Seminoma/genética , Desarrollo Sexual/genética , Neoplasias Testiculares/genética , Adolescente , Argentina/epidemiología , Carcinoma in Situ/química , Carcinoma in Situ/epidemiología , Carcinoma in Situ/patología , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Disgenesia Gonadal/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Factor 3 de Transcripción de Unión a Octámeros/análisis , Fenotipo , Ploidias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Seminoma/química , Seminoma/epidemiología , Seminoma/patología , Neoplasias Testiculares/química , Neoplasias Testiculares/epidemiología , Neoplasias Testiculares/patología , Adulto Joven
4.
J Clin Endocrinol Metab ; 76(5): 1325-31, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8496325

RESUMEN

The objective of this study was to describe the maturational changes observed in the seminiferous tubules of the monkey Cebus apella, a New World primate species, from birth to the end of puberty. Nineteen animals were subdivided into four groups: neonatal (1-40 days), infantile (4 months to 1 yr), early pubertal (1 yr, 8 months to 2 yr, 9 months), and late pubertal (4-8 yr). Volumetric determinations of different testicular components were made, tubule diameter and length were calculated, and spermatogenic cells, Sertoli cells, and androgen-binding protein secretion were quantified. Testicular and seminiferous tubule volumes increased significantly in the first 5 months of life and during puberty due to the combined increment in seminiferous tubule diameter and length. The total number of spermatogonia increased until late puberty to stabilize subsequently. Spermatocytes and spermatids appeared during puberty and increased dramatically until the end of this period. The germ cell ratios, indicative of spermatogenic efficiency, improved continuously in late puberty coincidentally with a reduction of spermatocyte degeneration. Sertoli cells proliferated in the neonatal and infantile periods, determining a longitudinal growth of the seminiferous tubules, but remained stable during puberty, when androgen-binding protein secretion increased significantly. The multiplication of germ cells is the main factor responsible for the increment in tubule diameter during puberty and determines the most noticeable postnatal modification of testicular volume. During late puberty, the reduction of spermatocyte degeneration leads to an increment in germ cell ratios and a progressive, but slow, improvement of spermatogenic efficiency, explaining why pubertal development of the testis occurs over such a prolonged period in this primate. This is in contrast to what happens in most laboratory animals and suggests that the Cebus is a useful model for studies of human male puberty.


Asunto(s)
Envejecimiento/fisiología , Animales Recién Nacidos/crecimiento & desarrollo , Cebus/anatomía & histología , Cebus/fisiología , Túbulos Seminíferos/anatomía & histología , Túbulos Seminíferos/fisiología , Maduración Sexual , Testículo/crecimiento & desarrollo , Proteína de Unión a Andrógenos/metabolismo , Animales , Células Germinativas/citología , Masculino , Túbulos Seminíferos/citología , Células de Sertoli/citología
5.
Fertil Steril ; 47(2): 310-6, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3545911

RESUMEN

Three patients with primary sterility in whom the majority of spermatozoa lacked a normally implanted head are presented. A small cephalic knob was evident in most of them by routine colorimetric techniques, and the Feulgen reaction failed to show any deoxyribose nucleic acid. The morphologic features of the tails was normal. Few loose sperm heads were observed in the ejaculates. Even though motility was decreased, there were numerous acephalic sperms with different degrees of forward motility. Electron microscopy showed a well-organized structure of the centrioles and connecting piece, which were located in the neck region within a small cytoplasmic mass, but no chromatin was detected in any case. Studies on immature spermatids present in semen evidenced an independent anomalous development of heads and tails and suggested that they became separated at the end of spermatid maturation. This anomaly, of probable genetic origin, is interpreted to be due either to an alteration in the mechanism of migration and positioning of the tail on the caudal pole of the nucleus or to an interference with the formation of the implantation fossa of the head, which normally accommodates the connecting piece.


Asunto(s)
Infertilidad Masculina/diagnóstico , Cabeza del Espermatozoide/anomalías , Espermatozoides/anomalías , Adulto , Técnicas Citológicas , Fertilización , Humanos , Masculino , Microscopía Electrónica , Cabeza del Espermatozoide/ultraestructura , Motilidad Espermática , Cola del Espermatozoide/ultraestructura , Síndrome
6.
Fertil Steril ; 48(4): 664-9, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3653424

RESUMEN

A study of a group of five patients presenting with primary sterility and showing severe sperm immotility is presented. Most spermatozoa in these patients showed rigid, short, thick, and/or irregular tails and 95 to 100% were immotile. Electron-microscopy disclosed a common pattern of flagellar abnormalities. There was a dysplastic development of the fibrous sheath, which appeared hyperplastic and disorganized. The axoneme was either missing or grossly distorted. In a few instances, a normal flagellum could be identified. Similar alterations also were detected in maturing spermatids, suggesting that the described defect develops during spermiogenesis. Two of the five patients had recurrent bronchial and sinusal infections and bronchiectasis, suggesting the possible existence of an associated abnormality in respiratory cilia. The existence of a common ultrastructural defect affecting most spermatozoa, its presence in two brothers, and the possibility of association with immotile respiratory cilia point to the existence of a syndrome (namely the "dysplasia of the fibrous sheath") of possible familial transmission.


Asunto(s)
Infertilidad Masculina/patología , Motilidad Espermática , Espermatozoides/anomalías , Adulto , Citoplasma/ultraestructura , Flagelos/ultraestructura , Humanos , Infertilidad Masculina/fisiopatología , Masculino , Microscopía Electrónica , Microtúbulos/ultraestructura , Espermatozoides/ultraestructura
7.
J Androl ; 5(4): 235-42, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6432758

RESUMEN

.he effect of high doses of testosterone propionate (TP) on the development of the first spermatogenic wave was systematically analyzed to determine the period of maximal susceptibility to testosterone. Two mg of TP were administered daily to groups of immature male rats, starting from birth, or days 5, 10, 15, and 20 until day 35 of life. Animals injected from birth or day 5 showed severe testicular atrophy, with reductions of more than 70% of testicular weight, diminished tubular diameters, and spermatogenic arrest during the meiotic prophase. Groups treated from days 10 or 15 showed increasing testicular weights with qualitatively normal spermatogenesis. When treatment started at 20 days, completely normal testicular development was achieved. To test the responsiveness of the neonatal hypothalamo-pituitary axis to TP administration, groups of 5-day-old male rats received daily injections of TP, and plasma FSH was determined at ten, 20, and 35 days. FSH levels were not detectable at ten and 20 days, and extremely depressed at 35. A group of 5-day-old male rats was injected simultaneously with 2 mg of TP and 14 IU of FSH (human menopausal gonadotropin: 71 IU of FSH and 80 IU of LH/ml) until day 35. Testicular weights and tubular diameters were increased compared to controls, and spermatid differentiation had proceeded to more mature steps than those seen in control animals. Inhibition of testicular development by neonatal TP administration was paralleled by a sharp decrease in circulating FSH levels and reversed by FSH replacement.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Animales Recién Nacidos/fisiología , Hormona Folículo Estimulante/fisiología , Espermatogénesis/efectos de los fármacos , Testosterona/farmacología , Envejecimiento , Animales , Hormona Folículo Estimulante/sangre , Masculino , Meiosis , Menotropinas/farmacología , Tamaño de los Órganos/efectos de los fármacos , Ratas , Túbulos Seminíferos/crecimiento & desarrollo , Testículo/crecimiento & desarrollo , Testosterona/administración & dosificación
8.
J Androl ; 6(2): 102-12, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3886616

RESUMEN

The process of early testosterone (T) secretion and Leydig cell differentiation in humans was studied to explore the steroidogenic capacity of Leydig cell fibroblastic precursors. Seven cryptorchid boys received hCG prior to orchidopexy. Patients CP, PB, and MR received one injection of 1000 IU; patients JR and GG, three daily injections of 1000 IU, and patients MP and MM, five daily injections of 1000 IU. A testicular biopsy was obtained at the time of operation, 24 hours after the last injection. Serum T (ng/dl) before and after hCG stimulation and testicular T (ng/g) were determined by RIA. A control prepubertal testis (tumoral orchidectomy) was incubated in vitro and showed a time-dependent accumulation of T both in the medium and the testicular tissue. Testosterone released into the medium at 1, 2, and 4 hours was 0.76, 1.43, and 4.03 ng/ml, respectively. Tissue T at 0, 1, 2, and 4 hours was 9, 11, 16, and 24 ng/g, respectively. This indicates synthesis and secretion of T into the medium. Control testes showed abundant fibroblastic precursors with scanty cytoplasm, few organelles, heterochromatic nuclei, and minute nucleoli. No Leydig cells were present. After 1 day of hCG stimulation, numerous fibroblasts were activated, displaying enlarged cytoplasms with increased numbers of organelles, nuclei rich in euchromatin, and bigger nucleoli. No Leydig cells were present. Basal serum testosterone was 58.2 +/- 45.3 ng/dl and 87.3 +/- 42.0 after hCG administration, while testicular T was 974.0 +/- 686.0 ng/g (control prepubertal testicular T is 10-50 ng/g). After 3 days of hCG, activated fibroblasts increased and immature Leydig cells appeared. Basal serum T was 35.5 +/- 7.8 ng/dl and 394.0 +/- 24.0 after hCG stimulation, while testicular T rose to 2797.5 +/- 1222.6 ng/g. After 5 days, mature Leydig cells appeared for the first time. Serum T was 58 +/- 59.3 ng/dl (basal) and 641.5 +/- 390 ng/dl (after hCG); testicular T was 789 ng/g (patient MM did not have a value for testicular T). HCG induced numerous coated pits and endocytic vesicles in activated fibroblasts and young Leydig cells, suggesting receptor aggregation and internalization of hormone-receptor complexes. Peroxidase-antiperoxidase (PAP) localization of T was positive in peritubular fibroblasts and Leydig cells.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Gonadotropina Coriónica/farmacología , Células Intersticiales del Testículo/metabolismo , Testosterona/biosíntesis , Andrógenos/inmunología , Niño , Preescolar , Fibroblastos/metabolismo , Humanos , Técnicas para Inmunoenzimas , Masculino , Pubertad , Estimulación Química , Testículo/citología , Testículo/metabolismo , Testículo/ultraestructura , Testosterona/sangre
9.
J Androl ; 22(2): 302-15, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11229805

RESUMEN

Dysplasia of the fibrous sheath (DFS) is characterized by male infertility, asthenozoospermia, and morphologically abnormal flagella that possess a severely malformed fibrous sheath. In many cases, DFS is familial, suggesting a genetic component. Human AKAP4 and AKAP3 are structural proteins of the fibrous sheath that also function to anchor protein kinase A to this structure via the regulatory subunit of the kinase. We hypothesized that defects in either AKAP4 or AKAP3 might cause DFS. No quantitative or qualitative differences between patients with DFS and normal controls were detected when sperm proteins were analyzed by either silver staining or immunoblot analysis using antibodies raised against AKAP4 and AKAP3. Additionally, AKAP4 and AKAP3 from DFS sperm retained the ability to bind the regulatory subunit of protein kinase A. Localization at the light and electron microscopic levels showed that AKAP3 and AKAP4 localized correctly to the FS of the amorphous flagellum in DFS sperm. Partial sequence analysis of the AKAP4 and AKAP3 genes in patients with DFS did not identify any significant alterations in potential AKAP4/AKAP3 binding regions, suggesting that the two proteins interact normally in DFS sperm. Our results did not find evidence to support the hypothesis that mutations in either gene are responsible for DFS in humans.


Asunto(s)
Proteínas Portadoras/genética , Enfermedades de los Genitales Masculinos/genética , Espermatozoides/metabolismo , Adulto , Secuencia de Bases , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunohistoquímica , Focalización Isoeléctrica , Masculino , Microscopía Inmunoelectrónica , Reacción en Cadena de la Polimerasa
10.
J Androl ; 6(1): 10-4, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3972716

RESUMEN

The effects of short-term hypoprolactinemia on the pituitary-gonadal axis were evaluated in a group of patients with untreated prostatic carcinoma. Each patient was studied prior to and during 7-day oral administrations of bromocriptine (2.5 mg q.i.d.). Serum LH, prolactin (PRL), androst-4-ene-3,17 dione (androstenedione), testosterone, and 5 alpha-androstane-3 alpha, 17 beta-diol (5 alpha-Diol) levels, as well as intra-testicular testosterone, dihydrotestosterone (DHT), 5 alpha-Diol and zinc (Zn) concentrations, were determined. Daily administration of bromocriptine caused a marked suppression of serum PRL (mean +/- SEM, 23.8 +/- 2.5 vs. 6.4 +/- 1.0 ng/ml) without concomitant changes in serum LH levels (mean +/- SEM, 8.3 +/- 1.6 vs. 8.9 +/- 2.1 ng/ml). Hypoprolactinemia induced a significant decrease (P less than 0.05) in the mean peripheral testosterone levels; but 5 alpha-Diol and androstenedione remained unchanged. However, in testicular tissues, bromocriptine treatment resulted in significant increases in mean concentrations of total androgens (P less than 0.001), testosterone (P less than 0.001) and DHT (P less than 0.02). Testicular levels of 5 alpha-Diol were not significantly altered. There was no change in Zn levels in basal conditions and during bromocriptine administration. These results indicate that short-term suppression of serum PRL levels in man affects basal testicular function without altering serum LH. However, a direct action of bromocriptine on the human gonad cannot be excluded.


Asunto(s)
Andrógenos/biosíntesis , Bromocriptina/uso terapéutico , Prolactina/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Testículo/metabolismo , Anciano , Andrógenos/sangre , Dihidrotestosterona/sangre , Humanos , Masculino , Persona de Mediana Edad , Prolactina/fisiología , Neoplasias de la Próstata/sangre , Testículo/efectos de los fármacos , Testículo/patología , Testosterona/sangre , Zinc/metabolismo
11.
Asian J Androl ; 1(1-2): 73-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11225909

RESUMEN

AIM: To study a 46, XY newborn patient with a phenotype suggestive of an androgen insensitivity syndrome to confirm an anomaly in the AR gene. METHODS: Genomic DNA from leukocytes was isolated in order to analyze SRY gene by PCR and sequencing of the eight exons of AR gene. Isolation of human Leydig cell mesenchymal precursors from the testis was performed in order to study testosterone production and response to hCG stimulation in culture. RESULTS: Surgical exploration disclosed two testes, no Wolffian structures and important Müllerian derivatives. The SRY gene was present in peripheral blood leukocytes. Sequencing of the AR gene evidenced a previously unreported G to T transversion in exon 1 that changed the normal glutamine 153 codon to a stop codon. Interstitial cell cultures produced sizable amounts of testosterone and were responsive to hCG stimulation. CONCLUSION: This E153X nonsense point mutation has not been described previously in cases of AIS, and could lead to the synthesis of a short truncated (153 vs 919 residues) non functional AR probably responsible for the phenotype of complete androgen insensitivity syndrome (CAIS).


Asunto(s)
Síndrome de Resistencia Androgénica/genética , Proteínas Nucleares , Mutación Puntual , Receptores Androgénicos/genética , Factores de Transcripción , Proteínas de Unión al ADN/genética , Humanos , Recién Nacido , Masculino , Linaje , Proteína de la Región Y Determinante del Sexo , Testículo/patología
12.
Asian J Androl ; 2(2): 125-30, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11232789

RESUMEN

AIM: Dysplasia of the fibrous sheath (DFS) is an anomaly found in asthenozoospermic patients with extremely low or absent motility. In order to determine the efficacy of ICSI in these patients, a retrospective analysis of ICSI results in DFS patients has been done. METHODS: Ten ICSI attempts were performed in 6 patients with diagnosis of Dysplasia of the Fibrous Sheath studied by transmission and scanning electron microscopy. RESULTS: In the cases studied, sperm concentration was (29.62 +/- 18.05) x 10(6)/mL, total motility was 1.14 +/- 1.31%. Progressive motility was 0% except for one case with 0.1% . One hundred and three preovulatory oocytes were obtained and 94 metaphase II oocytes were injected. Sixty-nine of them showed two pronuclei (fertilization rate: 73.4%). Forty-nine embryos were obtained and 34 were transferred (mean: 3.4 embryos per transfer). Five pregnancies were diagnosed by beta-hCG plasma level determinations that resulted to be one preclinical abortion, one clinical abortion and three deliveries. Another pregnancy (ongoing) was achieved from a cryopreserved embryo transfer. CONCLUSION: These results showed that ICSI provides a suitable solution for patients suffering from irreversible sperm defects such as DFS. Nevertheless, it is mandatory to inform couples of possible transmission risks to offspring, which are unknown at present. Only when the etiology of this problem is disclosed, it will be possible to assess the real genetic risk.


Asunto(s)
Trastornos de la Motilidad Ciliar , Embarazo/estadística & datos numéricos , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides , Adulto , Femenino , Humanos , Masculino , Microscopía Electrónica , Estudios Retrospectivos
13.
Tissue Cell ; 11(1): 147-62, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-451991

RESUMEN

Changes in number of nuclear pores in different states of physiologica activity have been reported, but little is known about changing patterns of distribution in the course of cell differentiation. Pore distribution in male germ cells was studied in freeze fracture preparations of immature and mature rodent testis. As in other somatic cells, pores were uniformly and apparently randomly distributed in Sertoli cell nuclei. The nucleus of gonocytes and spermatogonia showed varying degrees of pore clustering. Spermatocytes invariably exhibited very striking pore aggregation with close hexagonal packing in pore-rich areas, and large pore-free areas. In early spermatids, pores appeared to be randomly distributed. As the acrosome formed and spread over the apical pole of the nucleus, pores disappeared ahead of its advancing margin and became more concentrated in the post-acrosomal region. The relationship of pore complexes to the chromosomes and the role of the fibrous lamina are discussed. The question as to whether the changing patterns observed involve movement of pores within fluid nuclear membranes, or a dissolution and reformation of new pores remains unanswered.


Asunto(s)
Membrana Nuclear/ultraestructura , Espermatogénesis , Espermatozoides/citología , Testículo/citología , Animales , Diferenciación Celular , Técnica de Fractura por Congelación , Cobayas , Masculino , Ratones , Ratas , Células de Sertoli/ultraestructura , Espermátides/ultraestructura , Espermatocitos/ultraestructura , Espermatogonias/ultraestructura
17.
Int J Androl ; 24(1): 2-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11168644

RESUMEN

Postnatal evolution of the testis in most laboratory animals is characterized by the close continuity between neonatal activation and pubertal development. In higher primates, infancy, a long period of variable duration, separates birth from the beginning of puberty. This period has been classically considered as a quiescent phase of testicular development, but is actually characterized by intense, yet inapparent activity. Testicular volume increases vigorously shortly after birth and in early infancy due to the growth in length of seminiferous cords. This longitudinal growth results from active proliferation of infantile Sertoli cells which otherwise display a unique array of functional capabilities (oestrogen and anti-müllerian hormone secretion, increase of FSH receptors and maximal response to FSH). Leydig cells also show recrudescence after birth, possibly determined by an active gonadotrophic-testicular axis which results in increased testosterone secretion of uncertain functional role. This postnatal activation slowly subsides during late infancy when periodic phases of activation of the hypothalamo-pituitary-testicular axis are paralleled by incomplete spermatogenic spurts. The beginning of puberty is marked by the simultaneous reawakening of Leydig cell function and succeeding phases of germ cell differentiation/degeneration which ultimately lead to final spermatogenic maturation. The marked testicular growth in this stage is due to progressive increase at seminiferous tubule diameter. Sertoli cells, which have reached mitotic arrest, develop and differentiate, establishing the seminiferous tubule barrier, fluid secretion and lumen formation, and acquiring cyclic morphological and metabolic variations characteristic of the mature stage. All of these modifications indicate that, far from being quiescent, the testis in primates experiences numerous changes during infancy, and that the potential for pubertal development and normal adult fertility depends on the successful completion of these changes.


Asunto(s)
Testículo/crecimiento & desarrollo , Animales , División Celular , Humanos , Lactante , Células Intersticiales del Testículo/citología , Masculino , Primates , Túbulos Seminíferos/citología , Células de Sertoli/citología , Espermatozoides/citología
18.
Pediatr Pathol ; 7(2): 175-89, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2821524

RESUMEN

In 8 children (6 males) at least 2 of 3 disorders were found--male pseudohermaphroditism (MPH), Wilm's tumor, and glomerular disease. MPH was present in the 6 males; they had abdominal cryptorchidism (6/6), ambiguous genitalia (6/6), negative sex chromatin (5/5), and 46XY karyotype (2/2). The gonads examined microscopically in 3 patients were dysgenetic testes. The renal tumor present in 7 was nephroblastoma (NB) of the classical type without anaplasia or nephroblastomatosis, bilateral in 1, and unilateral but multinodular in 2. Five underwent nephrectomy for a renal mass, and in 2 NB was found at open biopsy or at autopsy. The mean age at diagnosis was 10 months. Glomerular disease in 6 patients began with onset of the nephrotic syndrome between 20 days and 39 months of age; it was resistant to steroid therapy and led to death from renal failure. Microscopically the glomerular process was a diffuse mesangial sclerosis (DMS). The 2 children with NB and MPH, but without DMS are healthy 2 1/2 and 9 years postnephrectomy. Neither familial incidence nor parental consanguinity was found. This syndrome has complete and partial forms, and its early recognition is important both for patient management and for assessment of prognosis.


Asunto(s)
Trastornos del Desarrollo Sexual/complicaciones , Enfermedades Renales/complicaciones , Tumor de Wilms/complicaciones , Preescolar , Trastornos del Desarrollo Sexual/patología , Femenino , Histocitoquímica , Humanos , Lactante , Recién Nacido , Enfermedades Renales/patología , Glomérulos Renales/patología , Masculino , Síndrome , Tumor de Wilms/patología
19.
Anat Rec ; 192(4): 493-512, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-736270

RESUMEN

Different types of human germ cells show unusual features of the nuclear envelope. Spermatogonial nuclei demonstrate two kinds of modifications. The first one is a series of intranuclear flattened cisterns, parallel to each other and to the inner aspect of the nuclear envelope. The second one is a nuclear envelope protrusion into the cytoplasm occupied by a double membrane-limited vesicle. Pores are found on the membrane of the vesicle facing the interior of the nucleus. In spermatocytes the nuclear pores are concentrated over certain areas and completely absent from others. In the regions where they are absent a single cytoplasmic cistern of rough endoplasmic reticulum is closely apposed to the outer membrane of the nuclear envelope. Early modifications of the nuclear surface appear in spermatids before the attachment of the acrosomic vesicle and may indicate an active role of the nuclear envelope in the morphogenesis of the acrosome. In round spermatids nuclear pores are absent from the area which is first related to the Golgi and later covered by the acrosomal cap. Single or multiple layers of cytoplasmic annulate lamellae are closely associated with the nuclear envelope over the pore rich areas. Frequently there are intranuclear accumulations of dense material adjacent to the annulate lamellae-nuclear pore complex. The chromatoid body is usually present on the cytoplasmic side of this complex. In the elongating spermatids most annulate lamellae are free in the cytoplasm, often in relation with Golgi and chromatoid body remnants near the axial filament. Few stacks of annulate lamellae are noted adjacent to the pore rich nuclear regions. It is suggested that the described modifications are related to an active nuclear-cytoplasmic interaction.


Asunto(s)
Espermatogénesis , Adulto , Permeabilidad de la Membrana Celular , Cromatina/ultraestructura , Citoplasma/ultraestructura , Gránulos Citoplasmáticos/ultraestructura , Retículo Endoplásmico/ultraestructura , Aparato de Golgi/ultraestructura , Humanos , Masculino , Membrana Nuclear/ultraestructura , Organoides/ultraestructura , Espermátides/ultraestructura , Espermatocitos/ultraestructura , Espermatogonias/ultraestructura
20.
Int J Androl ; 13(3): 216-22, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2387641

RESUMEN

Two patients suspected of suffering from ciliary dyskinesis were investigated. They consulted for primary infertility and chronic respiratory disease. Functional lung studies showed obstructive changes in one patient. Both had immotile sperm with short, thick and rigid tails. Ultrastructural studies of nasal biopsies showed abnormal cilia with almost complete lack of inner dynein arms (mean number of inner arms per axoneme 0.67 +/- 1.21 in patient 1 and 1.49 +/- 1.17 in patient 2, compared with normal values of 5.3 +/- 0.13). Other abnormalities included lack of parallel orientation of cilia and central translocation of microtubular doublets. Electron microscopy of sperm revealed hyperplasia of the fibrous sheath and axonemal disruption. This is the first report of an association of different anomalies in cilia and flagella leading to clinical manifestation of the immotile cilia syndrome. These findings emphasize the need for ultrastructural examination of respiratory cilia in men suffering from fibrous sheath alterations of sperm which so far have not been described in patients with the classical form of immotile cilia syndrome.


Asunto(s)
Trastornos de la Motilidad Ciliar/patología , Infertilidad Masculina/patología , Espermatozoides/ultraestructura , Adulto , Cilios/ultraestructura , Trastornos de la Motilidad Ciliar/complicaciones , Flagelos/ultraestructura , Humanos , Infertilidad Masculina/complicaciones , Masculino , Mucosa Nasal/ultraestructura , Pruebas de Función Respiratoria , Cola del Espermatozoide/ultraestructura
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda