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1.
Theriogenology ; 83(7): 1188-93, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25617987

RESUMO

The main aim of the study was to assess whether the longer use of a GnRH-agonist implant (deslorelin 4.7 mg, Suprelorin) in toms would lead to the suppression of spermatogenesis comparable with histologic appearance in juvenile animals as was previously described in dogs. The other aims were to monitor the progression of the testes size decrease and development of azoospermia 5 to 7 months after treatment with a GnRH-agonist implant. In animals, 5, 6, and 7 months after GnRH-agonist implant insertion, variable histological appearance of germinal epithelium was found, when tubules with elongating spermatids, round spermatids, spermatocytes, and spermatogonia as the most developed germinal cells were found in each group of toms. In all male cats, 5, 6, and 7 months after implant insertion, testosterone concentrations and testes size significantly differed between the first and the last visit. All animals, except one tom castrated 5 months after implant insertion, developed complete azoospermia. However, in this tom, all spermatozoa were immotile. Treatment with the subcutaneous GnRH-agonist implant was well tolerated, and no treatment-related adverse effects were noted. These results reported the efficacy of 4.7-mg deslorelin implant (Suprelorin) during its 7 months of use. The complete azoospermia confirms its contraceptive effect. However, the histologic evaluation revealed a great individual variability in the degree of spermatogenic suppression. The question as to whether spermatogenesis in toms can be suppressed in all males to the level of spermatogonia/primary spermatocytes after prolonged exposure to deslorelin has yet to be answered.


Assuntos
Gatos , Anticoncepção/veterinária , Hormônio Liberador de Gonadotropina/agonistas , Espermatogênese/efeitos dos fármacos , Testículo/anatomia & histologia , Pamoato de Triptorrelina/análogos & derivados , Animais , Azoospermia/induzido quimicamente , Azoospermia/veterinária , Anticoncepção/métodos , Anticoncepcionais Masculinos/administração & dosagem , Implantes de Medicamento , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Pamoato de Triptorrelina/administração & dosagem
2.
Andrologia ; 46(8): 831-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24007278

RESUMO

Globozoospermia, characterised by the presence of round spermatozoa lacking acrosomes in an ejaculate, is a known cause of male infertility. Semen analysis, including sperm chromatin structure assay, toluidine blue, chromomycin A3 and aniline blue staining and fluorescence in situ hybridisation, was performed in an infertile globozoospermic patient to establish to which extent these genetic factors contributed to his infertility. No spermatozoa capable of hyaluronan (HA) binding were detected in the HA binding assay. Increased rates of immature spermatozoa with defective replacement of histones by protamines, DNA breaks and disturbed chromatin integrity and sperm aneuploid for the sex chromosomes were observed. Intracytoplasmic sperm injection (ICSI) was used in three in vitro fertilisation (IVF) cycles, and enough morphologically well-developing embryos were obtained in each cycle. However, no pregnancy was achieved. The infertility of our couple, resistant to IVF/ICSI treatment, was most probably caused by a combination of male and female factors.


Assuntos
Aneuploidia , Infertilidade Masculina/genética , Adulto , Quebras de DNA , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise do Sêmen/métodos
3.
Theriogenology ; 78(4): 848-57, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22578617

RESUMO

The aim of the study was to assess the efficacy of using a Gn-RH agonist implant (deslorelin, 4.7 mg, Suprelorin) to control sexual activity of male cats and reestablishment of sexual function after the implant removal 4 mo after placement. Using a control group (Group 1, n = 5), 22 domestic tomcats were given the implant subcutaneously in the region of the right shoulder blade and were then divided into two treatment groups. Animals in Group 2 (n = 14) were observed from the date of implant surgery and the observation lasted for 4 mo. In Group 3 (n = 8) all animals were monitored from the date of implant surgery. Then, after 4 mo, all implants were removed and the toms were observed for a further 4 mo. In all animals during their first visit and then in 1-mo intervals, changes in testosterone concentrations were assessed before (T0) and 4 h after (T4) human chorionic gonadotropin (HCG) administration and testis size was measured. In all tomcats, semen collection was performed, using an electroejaculator, in the course of the first visit and then in 2-mo intervals or at the end of observation. Total sperm count was determined in each semen sample. Two to four animals were castrated at weeks 4, 8, 12, 16, 20, 24, 28 and 32 and histologic assessment of the testes was performed. By evaluation of 200 cross sections of seminiferous tubules, the degree of spermatogenic suppression was assessed and animals in Groups 2 and 3 were assigned into groups according to most tubules with the most developed germ cell observed: G1, spermatocytes; G2, round spermatids; G3, elongating spermatids and G4, elongated spermatids. The mean area of Leydig-cell nuclei was calculated. In animals in Group 2, suppression after implant insertion was monitored. T4 concentrations, testis size, and total sperm count gradually decreased (P < 0.01; P < 0.01; and P < 0.05, respectively) within 4 mo after implantation. Histologic evaluation showed a high individual variation in the degree of suppression of spermatogenesis. In animals in Group 3, the implant was removed 4 mo after insertion and the return of sexual activity was monitored. Within 4 mo, T4 concentration and total sperm count increased to the physiological values of intact toms. Testes gradually increased in size and within 4 mo of implant removal almost reached pretreatment size. According to histologic evaluation of the seminiferous tubules, as early as 1 mo after implant removal, all animals were assigned to G4, with most tubules containing elongated spermatids as the most developed germ cells. Treatment with the long-term subcutaneous Gn-RH agonist implant was well tolerated and no adverse treatment-related effects were noted. These results demonstrated efficacy of 4.7 mg deslorelin implant (Suprelorin) with high variability of the effect onset in tomcats. Furthermore, the study revealed a strong need for complex examination, including testis size measurement, monitoring of hormonal changes, spermatological analysis and histologic evaluation, to declare the animal infertile. After the implant removal, all observed parameters confirmed the reversibility of the method and gradual return of sexual activity in toms.


Assuntos
Gatos , Anticoncepção/veterinária , Recuperação de Função Fisiológica/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Pamoato de Triptorrelina/análogos & derivados , Animais , Gatos/anatomia & histologia , Gatos/sangue , Gatos/fisiologia , Anticoncepção/métodos , Anticoncepcionais Masculinos/administração & dosagem , Regulação para Baixo/efeitos dos fármacos , Implantes de Medicamento , Ejaculação/efeitos dos fármacos , Ejaculação/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Concentração Osmolar , Recuperação de Função Fisiológica/fisiologia , Comportamento Sexual Animal/fisiologia , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testículo/fisiologia , Testosterona/sangue , Pamoato de Triptorrelina/administração & dosagem , Suspensão de Tratamento
4.
Hum Reprod ; 27(3): 930-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22238111

RESUMO

BACKGROUND: The swim-up and hyaluronan (HA)-binding methods are used for the selection of good quality spermatozoa to improve pregnancy rates and embryo quality and to reduce the number of miscarriages after IVF. We evaluated whether the processing of sperm by these methods reduces the frequency of spermatozoa with abnormal karyotypes and altered chromatin quality in balanced translocation carriers. METHODS: Semen samples of 12 carriers of balanced chromosomal translocations were analysed for the frequency of spermatozoa, which are chromosomally unbalanced due to the segregation of balanced translocations, aneuploidies for chromosomes 7, 8, 13, 18, 21, X or Y, diploid sperm or sperm with fragmented DNA and poorly condensed chromatin. Results obtained by fluorescence in situ hybridization (FISH) and sperm chromatin structure assay were compared between ejaculated (n = 12), swim-up (n = 12) and HA-binding processed (n = 6) semen samples of the translocation carriers and with the control group (n = 10). RESULTS: The mean frequencies of unbalanced segregation products were 17.5 and 16.5% in neat and swim-up processed samples from Robertsonian translocation carriers, and 55.4, 54.5 and 50.9% in neat, swim-up and HA-bound sperm samples from reciprocal translocation carriers. Significant decreases in the frequency of sperm showing chromosome 18 and XY disomy and of diploidy, and in the rates of high-density staining sperm were observed in the motile swim-up fractions. There were significantly more sperm showing fragmented chromatin in the group of translocation carriers than in the control group, but no differences in the aneuploidy and diploidy rates were observed. CONCLUSIONS: The swim-up method is suitable for selection of sperm with condensed chromatin and a lower frequency of some aneuploidies and of diploidy. The frequency of spermatozoa chromosomally unbalanced due to the segregation of reciprocal (but not Robertsonian) translocations is significantly lower in HA-bound sperm. However, the advantages of either method for selecting normal sperm are limited.


Assuntos
Heterozigoto , Análise do Sêmen/métodos , Espermatozoides/anormalidades , Translocação Genética , Adulto , Segregação de Cromossomos , Humanos , Ácido Hialurônico/análise , Hibridização in Situ Fluorescente , Masculino
5.
Andrologia ; 44 Suppl 1: 410-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21762193

RESUMO

A considerable proportion of male factor infertility cases are associated with inflammatory processes. The most common sexually transmissible agents causing sexually transmitted diseases in industrial countries are Chlamydia trachomatis, genital Ureaplasma and Mycoplasma spp. This study was undertaken to investigate whether these bacterial contaminants in semen affect sperm quality parameters and particularly DNA integrity (detected by sperm chromatin structure assay) in males from infertile couples (n = 293). The results showed that semen contaminations with the investigated bacterial species were not associated with sperm DNA fragmentation. However, contaminations with Mycoplasma spp. and C. trachomatis were associated with decreased sperm concentrations. Total sperm numbers in contaminated semen samples tended to be decreased, but not significantly. Mycoplasma had the highest adverse effect on sperm quality (concentration, motility, morphology and DNA condensation). Antibiotic therapy of the selected 47 men was successful in 55%, but semen quality parameters did not improve at least up to 3 months after the therapy. The presence of pathogenic bacteria in semen is primarily associated with low sperm production. Our data showed that Mycoplasma spp. contamination of semen had the highest adverse effect on sperm quality. Sperm chromatin integrity assessed by the presence of DNA breaks was not disturbed.


Assuntos
Cromatina/metabolismo , Infertilidade Masculina/microbiologia , Sêmen/microbiologia , Espermatozoides/metabolismo , Chlamydia trachomatis/isolamento & purificação , Fragmentação do DNA , Feminino , Humanos , Infertilidade Masculina/metabolismo , Masculino , Mycoplasma/isolamento & purificação , Ureaplasma/isolamento & purificação
6.
Andrologia ; 43(4): 286-91, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21486403

RESUMO

Obesity can adversely affect human health, including fertility. While obesity can disturb the hormonal profile of the female organism and is associated with fertility loss, little is known about what effect male obesity has on fertility. The present study analysed sperm samples of 153 donors. The men were selected from couples attending an infertility clinic, who had tried for 12 months or more to achieve pregnancy without success. The age of the men under investigation was recorded, and their body mass index (BMI) was calculated. All semen samples were assessed for volume, concentration, motility and morphology. Sperm chromatin integrity was measured by sperm chromatin structure assay. Quality of sperm chromatin condensation was assessed by toluidine blue, aniline blue and chromomycin A3 staining. We can conclude that the impact of elevated BMI on the parameters investigated (basic semen parameters, chromatin integrity and chromatin condensation) was not proven in this study. On the other hand, ejaculate quality appeared to be affected by ageing. The impact was reflected by chromatin integrity, which is a factor that can substantially affect fertility in men, rather than by basic sperm parameters.


Assuntos
Envelhecimento , Cromatina/genética , Infertilidade Masculina/etiologia , Obesidade/complicações , Análise do Sêmen , Espermatozoides/citologia , Adulto , Índice de Massa Corporal , Fragmentação do DNA , Humanos , Masculino , Pessoa de Meia-Idade , Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides
7.
Int J Androl ; 33(4): 613-22, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19751362

RESUMO

Aneuploidy is associated with spontaneous abortions, perinatal mortality, mental retardation and with embryonic and foetal mortality. Most of these abnormalities originate as a result of meiosis errors during gametogenesis. The main purpose of the study was to analyse frequency of aneuploidies of sex chromosomes and chromosome 6 by three-colour fluorescence in situ hybridization (FISH) in 47 young bulls, candidates for artificial insemination programme with cryopreserved semen and to investigate the influence of aneuploidies and disturbed sperm chromatin integrity on non-return rates, the frequencies of abortions, perinatal mortality and stillbirths. The average frequencies of spermatozoa with disomy for chromosomes X, Y, XY and 6 were 0.032, 0.005, 0.003 and 0.039% respectively. The incidence of XX66, YY66 and XY66 diploidy was 0.017, 0.006 and 0.015% respectively. Frequencies of meiotic II errors were significantly higher than meiotic I errors (p < 0.01). More X bearing spermatozoa than Y bearing spermatozoa were detected (5151 vs. 5022; p < 0.01). Sperm chromatin damage expressed by DNA fragmentation index (DFI) was 5.3 +/- 3.7 and percentage of cells with defective chromatin condensation (HDS) was 1.4 +/- 0.8. No correlation was found between sperm aneuploidy and basic sperm analysis. The relationship was found between non-return rate and total aneuploidy (r = -0.310; p = 0.036). Significant correlation was found between sex disomy, total aneuploidy (disomy of chromosomes 6, X, Y and XY spermatozoa and diploidy) and stillbirths (r = 0.390; p = 0.013; and r = 0.331; p = 0.037). Chromosome 6 disomy correlated with perinatal mortality (r = 0.317; p = 0.047). HDS correlated significantly with total aneuploidy (r = 0.449; p = 0.002). Our study indicated that aneuploidy frequencies in young fertile bull spermatozoa are relatively low. Nevertheless, there exists a variability in aneuploidy frequencies amongst bulls, which appears to be able to have an influence on the fertility of these animals.


Assuntos
Aneuploidia , Bovinos/genética , Cromatina/ultraestrutura , Fertilidade/genética , Espermatozoides/fisiologia , Animais , Fragmentação do DNA , Feminino , Hibridização in Situ Fluorescente , Masculino , Gravidez , Análise do Sêmen/veterinária
8.
Mutat Res ; 683(1-2): 9-15, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19800896

RESUMO

The purpose of the present study was to investigate the impact of carcinogenic polycyclic aromatic hydrocarbons and volatile organic compounds on sperm quality in a group of city policemen in Prague during a period of increased concentrations of ambient air-pollutants (winter season) compared to a period of low exposure (spring). Polymorphisms in metabolic genes (CYP1A1, EPHX1, GSTM1, GSTP1, GSTT1), folic acid metabolism genes (MTR, MTHFR) and DNA repair genes (XRCC1, XPD6, XPD23, hOGG1) were evaluated in these men as potential modifiers of associations between air pollution exposure and changes in sperm quality. The study population was a group of 47 policemen working in the center of the city. Seasonal differences in exposure were verified by ambient and personal monitoring. Markers of sperm injury included semen volume, sperm concentration, sperm morphology, sperm motility, and sperm DNA damage measured with the sperm chromatin structure assay The sperm chromatin structure assay (SCSA) includes a measure of DNA damage called DNA Fragmentation Index (DFI). The % of cells with detectable DFI (detDFI) by this assay includes sperm with either medium or high DNA damage; the term hDFI is used to define the % of sperm with only high DNA damage. The assay also detects immature sperm defined by high density staining (HDS). No significant differences were found in any of the standard semen parameters between the sampling periods except for vitality of sperms. Both DFI and HDS were significantly higher in winter than in spring samples for all men and for non-smokers. At the bivariate level, significant associations between hDFI or detDFI and polymorphisms of the repair genes XRCC1, XPD6 and XPD23 were observed. In multivariate models, polymorphisms of the genes XPD6, XPD23 and CYP1A1MspI were associated with hDFI and HDS. Moreover, HDS was significantly associated with polymorphisms in GSTM1 gene.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Dano ao DNA/genética , Fragmentação do DNA/efeitos dos fármacos , Enzimas Reparadoras do DNA/genética , Polimorfismo Genético , Espermatozoides/efeitos dos fármacos , Adulto , Cromatina/genética , Cotinina/urina , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Ácido Fólico/metabolismo , Genótipo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Masculino , Polícia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fumar , Proteína Grupo D do Xeroderma Pigmentoso/genética , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
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