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1.
Andrology ; 3(3): 552-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25767078

RESUMO

Conventional semen analysis offers basic information on infertility; however, its clinical value in predicting fertility status is unclear. To establish an accurate diagnosis of male fertility, semen analysis under capacitation condition is necessary because only capacitated spermatozoa are capable of fertilizing oocytes. The objective of this study was to verify male fertility based on conventional semen analysis before and after capacitation, including the assessment of motility (%), motion kinematics, and capacitation status of spermatozoa. A computer-assisted sperm analysis system and chlortetracycline staining were applied to evaluate the motility parameters and capacitation status, respectively. To enable efficacy of the two methods for predicting fertility, correlation analysis was performed with the historic litter size. Our results showed that sperm motility (%), motion kinematics, and their variations before and after capacitation represented a statistical non-significant correlation with litter size. Litter size showed significant correlation with acrosome reaction (AR) after capacitation (r = 0.375), as well as differences (Δ) in AR (r = 0.333) and capacitated (B) pattern (r = -0.447) before and after capacitation. The overall accuracy of the assay for predicting litter sizes using the AR and differences (Δ) in the AR and B pattern was 70%. On the basis of these results, we propose that capacitation status of spermatozoa is a more reliable indicator for evaluating male fertility status compared to motility parameters. Therefore, we suggest that analysis of capacitation status in company with conventional semen analysis may accept to evaluate more accurate diagnosis or prognosis of male fertility.


Assuntos
Reação Acrossômica/fisiologia , Inseminação Artificial/métodos , Tamanho da Ninhada de Vivíparos/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia , Animais , Bisbenzimidazol , Clortetraciclina , Feminino , Fertilidade , Infertilidade Masculina , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia , Coloração e Rotulagem , Sus scrofa
2.
Andrology ; 2(6): 899-909, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25180787

RESUMO

Sodium nitroprusside is a nitric oxide donor involved in the regulation of the motility, hyperactivation, capacitation, and acrosome reaction (AR) of spermatozoa. However, the molecular mechanism underlying this regulation has not yet been elucidated. Therefore, this study was designed to evaluate the molecular basis for the effects of sodium nitroprusside on different processes in spermatozoa and its consequences on subsequent oocyte fertilization and embryo development. In this in vitro study, mouse spermatozoa were incubated with various concentrations of sodium nitroprusside (1, 10, and 100 µM) for 90 min. Our results showed that sodium nitroprusside inhibited sperm motility and motion kinematics in a dose-dependent manner by significantly enhancing intracellular iron and reactive oxygen species (ROS), and decreasing Ca(2+), and adenosine triphosphate levels in spermatozoa. Moreover, short-term exposure of spermatozoa to sodium nitroprusside increased the tyrosine phosphorylation of sperm proteins involved in PKA-dependent regulation of intracellular calcium levels, which induced a robust AR. Finally, sodium nitroprusside significantly decreased the rates of fertilization and blastocyst formation during embryo development. Based on these results, we propose that sodium nitroprusside increases ROS production and precocious AR may alter overall sperm physiology, leading to poor fertilization and compromised embryonic development.


Assuntos
Fertilidade/efeitos dos fármacos , Nitroprussiato/farmacologia , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Técnicas In Vitro , Masculino , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Espermatozoides/metabolismo
3.
Epidemiol Infect ; 140(4): 665-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21676350

RESUMO

We analysed the data from the control group in a typhoid vaccine trial in Karachi to assess the differences in individual-, household- and cluster-level characteristics for developing typhoid fever. The annual incidence of typhoid in children aged 2-16 years in the control arm of the vaccine trial was 151/100 000 population. After adjustment, the risk of typhoid was lower with increasing age [risk ratio (RR) 0·89, 95% confidence interval (CI) 0·83-0·95], was higher with an increase in population density (RR 1·13, 95% CI 1·05-1·21) and was lower in the households using a safe drinking-water source (RR 0·63, 95% CI 0·41-0·99). Typhoid fever affects younger children living in areas of high population density and lack of access to safe water in Pakistan. A combination of environmental and biological interventions is required to prevent the continued epidemiological and economic impact of typhoid fever in high-risk areas of Pakistan.


Assuntos
Febre Tifoide/etiologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Água Potável/virologia , Características da Família , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Densidade Demográfica , Fatores de Risco , Salmonella typhi , Fatores Socioeconômicos , Febre Tifoide/epidemiologia , Vacinas Tíficas-Paratíficas/uso terapêutico
4.
Anim Reprod Sci ; 121(1-2): 131-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20573460

RESUMO

Semen parameters can be considered useful predictors of sperm fertility. The objective of this study was to address the question of whether differences in in vivo fertility after the use of different ejaculates could be predicted using sperm kinematics, capacitation status, and sperm penetration ability under commercial pig production conditions. The percentage of capacitated sperm, as assessed by chlortetracycline (CTC) staining, was positively correlated with litter size (p<0.01). Our data suggest that litter size increases in proportion to the number of capacitated spermatozoa. When all semen parameters (kinematics, sperm capacitation status, and sperm penetration ability) and litter size were included in a multiple linear regression analysis, significant associations were found between the percentage of capacitated sperm (B-type), the sperm fertility index as assessed by a sperm penetration assay (SPA), and litter size. This relationship between capacitated sperm and litter size, however, was more predictive for smaller litter groups than larger ones. We found that the percentage of B-type sperm was significantly correlated with historic average litter size. However, there was no significant correlation between the percentage of B-type sperm and historic farrowing rates. To determine the normal range for B-type sperm, the lower limits were established as 30% for small litters (<8 piglets) and 35% for large litters. The overall accuracy of the assay was 92% and 83% for small and large litters, respectively. These results indicate that capacitation status as measured by CTC staining is a useful predictor of sperm fertility, equivalent to SPA. Moreover, original capacitation status exhibited better predictive ability for small litters than for large ones. Therefore, subfertile boars can be identified primarily by capacitation status.


Assuntos
Tamanho da Ninhada de Vivíparos/fisiologia , Preservação do Sêmen , Capacitação Espermática/fisiologia , Suínos/fisiologia , Animais , Cricetinae , Feminino , Fertilidade/fisiologia , Fertilização in vitro/veterinária , Masculino , Modelos Teóricos , Gravidez , Sêmen/fisiologia , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/veterinária
5.
Ophthalmic Plast Reconstr Surg ; 17(2): 115-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11281583

RESUMO

PURPOSE: To assess the efficacy of intraoperative mitomycin C (MMC) in external dacryocystorhinostomy (EXT-DCR). METHODS: Forty-six cases (50 lacrimal drainage systems [LDS]) with nasolacrimal duct obstruction were randomized into three groups. In the control group, a standard EXT-DCR procedure was performed. In the two MMC groups, a piece of cotton soaked with 0.2 mg/ml MMC (group 1) or 0.5 mg/ml MMC (group 2) was applied to the nasal mucosa and the mucosa of the lacrimal sac in the osteotomy site for 5 minutes. RESULTS: The dacryocystorhinostomy in all patients was patent by irrigation 2 to 3 weeks postoperatively. After a mean follow-up interval of 35.2 +/- 5.3 months, the dacryocystorhinostomy was patent in 15 (83%) of 18 LDS in the control group, 16 (100%) of 16 LDS in group 1, and 15 (94%) of 16 LDS in group 2. The mean ostium sizes were 22.2 +/- 5.0 mm2 in group 1, 20.6 +/- 4.5 mm2 in group 2, and 13.2 +/- 2.7 mm2 in group 3 at the final follow-up visit; the difference between the patients treated with MMC and the control group was statistically significant. There was no statistically significant difference between the two MMC groups, however. No surgical complications occurred. CONCLUSIONS: Intraoperative MMC in DCR is a safe and effective adjuvant that helps achieve favorable long-term success rates.


Assuntos
Dacriocistorinostomia/métodos , Mitomicina/uso terapêutico , Mucosa Nasal/efeitos dos fármacos , Ducto Nasolacrimal/efeitos dos fármacos , Adolescente , Adulto , Idoso , Cicatriz/prevenção & controle , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
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