RESUMEN
OBJECTIVE: Considering that glucose is an important component of seminal plasma and is a cryoprotectant at high concentrations, the aim of this study was to investigate the possible association of glucose levels in fresh semen with the sperm survival and motility rates following cryopreservation. METHODS: This was a prospective study including 149 men undergoing semen analysis due to male and/or female infertility. The seminal samples were analyzed according to the World Health Organization standards and glucose concentrations were measured using a dipstick glucometer. Samples were cryopreserved with Test Yolk Buffer-Gentamicine freezing medium under liquid nitrogen for an average of 120 days. The frozen aliquots were thawed at 37°C for 10 minutes and analyzed using the same methods and protocols used pre-freezing. RESULTS: Glucose levels ranged from 14 to 99 mg/dL and were similar in individuals with normal (n=100) vs. abnormal (n=49) semen analysis. The rates of sperm recovery (total, alive or motile sperm) in the cryopreserved samples did not change among samples with different glucose levels (p>0.05, Kruskal-Wallis ANOVA and Spearman's correlation coefficient). CONCLUSIONS: There appears to be no association between glucose levels in human semen samples and their resistance to cryopreservation.
RESUMEN
BACKGROUND: Nodal is a growth factor of the transforming growth factor ß superfamily that is expressed in high turnover tissues, such as the human endometrium, and in several malignancies. The effects of Nodal are modulated by the coreceptor Cripto and mediated by SMAD proteins. This study evaluated the gene and protein expression of Nodal, Cripto, total and phosphorylated (p) SMAD3, and SMAD4 in the proliferative endometrium of women with and without endometriosis. METHOD: Total RNA was isolated and complementary DNA synthesized from eutopic endometrium of women with (n = 15) and without (n = 12) endometriosis, followed by quantitative real-time polymerase chain reaction (PCR) to evaluate the gene expression of Nodal, Cripto, SMAD3, and SMAD4. Western blot was used to evaluate the protein levels of Nodal and Cripto, and immunohistochemistry was performed to localize SMAD3, pSMAD3, and SMAD4. RESULTS: Although Nodal expression was unchanged in women with endometriosis, real-time PCR indicated lower gene expression of Cripto (fold change 0.27, P < .05) in the endometriosis group. This difference, however, was not maintained at protein expression level as assessed by Western blot. The immunostaining of total SMAD3 was reduced in the endometriosis group (P < .01), but the localization of pSMAD3 and the nuclear staining of SMAD4 were unchanged. CONCLUSION: These findings suggest that the Nodal signaling pathway has subtle changes in the endometrium of women with endometriosis, but this imbalance may not cause functional damage as it seems not to affect the nuclear expression of SMAD4.
Asunto(s)
Proliferación Celular , Endometriosis/metabolismo , Endometrio/química , Proteínas Ligadas a GPI/análisis , Péptidos y Proteínas de Señalización Intercelular/análisis , Proteínas de Neoplasias/análisis , Proteína Nodal/análisis , Proteína smad3/análisis , Proteína Smad4/análisis , Adulto , Western Blotting , Estudios de Casos y Controles , Endometriosis/diagnóstico , Endometriosis/genética , Endometrio/patología , Femenino , Proteínas Ligadas a GPI/genética , Regulación de la Expresión Génica , Humanos , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas de Neoplasias/genética , Proteína Nodal/genética , Fosforilación , ARN Mensajero/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal , Proteína smad3/genética , Proteína Smad4/genética , Adulto JovenRESUMEN
PURPOSE: To compare sperm recovery from slow versus rapid thawing technique using thirty-eight normozoospermic human sperm samples, as follows. Twentyone samples from men taking part in routine infertility screening exams (infertile group) and seventeen from proven fertile volunteer men with at least one child (fertile group). MATERIALS AND METHODS: After analysis of motility, concentration, strict morphology and functional integrity of membranes, sperm was divided into two aliquots of 0.5 mL each and frozen in TyB-G medium. Samples were thawed at room temperature (25 ± 2° C) for 25 minutes (slow thaw) or in a water bath at 75° C for 20 seconds followed by water bath at 37° C for 3 minutes (rapid thaw). After thawing, motility, strict morphology and functional integrity of membranes were evaluated by a blinded investigator. The results were expressed as mean ± standard deviation for parametric variables and analyzed using Student's t-test. Data with unpaired non-parametric variables were expressed as median (interquartile range) and analyzed by the Mann-Whitney test. Wilcoxon test was used to analyze non-parametric paired variables. RESULTS: There was no significant difference between techniques for total and progressive motility, percentage of normal morphological forms, hypoosmotic swelling test. CONCLUSIONS: Although the rapid thawing protocol was completed in a shorter time (three minutes and 20 seconds versus 25 minutes, respectively), it wasn't harmful since both techniques showed comparable spermatozoa recovery. Additional research is needed to confirm its safety in clinical research before introducing this methodology in routine assisted reproduction.