Composición corporal en mujeres deportistas premenopáusicas y postmenopáusicas / Body composition in premenopausal and postmenopausal well-trained females

Objetivo: El propósito fue analizar la influencia de las hormonas sexuales en la composición corporal de deportistas con diferente estatus hormonal. Metodología: 46mujeres eumenorreicas, 41 usuarias de píldora anticonceptiva monofásica y 16mujeres postmenopáusicas bien entrenadas participaron en el estudio. Las voluntarias realizaron un Dual-energy X-ray Absorptiometry scan (DXA) y una bioimpedancia durante la fase folicular temprana y no hormonal, verificado con una analítica. Resultados: La prueba ANCOVA no mostró diferencias ni en las variables medidas con DXA (peso, masa grasa androide y ginoide, masa grasa total y masa libre de grasa) ni en las de bioimpedancia (peso, masa grasa, masa libre de grasa y agua corporal total). Conclusión: Las hormonas sexuales parecen no influir en la composición corporal de mujeres activas. Las mujeres postmenopáusicas activas presentan una distribución de masa grasa similar a las premenopáusicas, lo que podría explicarse por el efecto positivo de la actividad física. (AU)

Purpose: The aim was to analyse the influence of sex hormones on body composition in well-trained females with different hormonal environments.Methods: Sixty-six eumenorrheic, forty-one low-dose-monophasic oral contraceptive users and sixteen postmenopausal well-trained females participated in this study. Volunteers underwent a Dual-energy X-ray Absorptiometry scan (DXA) and a bioimpedance during the early-follicular and the withdrawal phase, verified with blood samples.Results: ANCOVA test reported no differences neither in DXA measurements (weight, fat free mass, fat mass, android and gynoid fat mass) nor in bioimpedance variables (weight, fat free mass, fat mass and total body water) among study groups.Conclusion: Sex hormones seems not to influence body composition in active women. Curiously, premenopausal and postmenopausal active women present the same fat mass distribution. It could be explained by the positive effect exercise has on body composition, and this in turn on preventing cardiovascular and metabolic diseases in this population. (AU)

Effects of reactive oxygen species on the physical properties of polypropylene surgical mesh at various concentrations: a model for inflammatory reaction as a cause for mesh embrittlement and failure.

BACKGROUND: Oxidative degradation by reactive oxygen species (ROS) from inflammation initiates cross-linking, depolymerization, and formation of a quasi-crystalline quality in polypropylene (PP) meshes that cause embrittlement (J Urol 188:1052, 2012). Embrittlement leads to change in tensile strength and is associated with post-operative complications that include pain, adhesion, dislodgment, and fragmentation. METHODS: A laboratory environment was constructed to study the relationship between concentration of ROS and change in tensile strength. Samples of Ethicon Ultrapro© PP mesh were exposed to 1 mM, 0.1 M, or 1 M hydrogen peroxide solutions for 6 months and were subjected to load displacement tensile testing (LDTT) and compared to unexposed (0 M) meshes of the same brand. RESULTS: Load at failure and elongation to failure after LDTT were determined with 95 % confidence interval. For unexposed (0 M) samples, tensile strength was 28.0 ± 2.4 lbf and elongation to failure was 2.0 ± 0.3 in. For samples exposed to 1 mM, tensile strength was 19.2 ± 1.1 lbf and the elongation to failure was 2.0 ± 0.1 in. For samples exposed to 0.1 M, tensile strength was 19.3 ± 1.6 lbf and elongation to failure was 1.9 ± 0.1 in. For samples exposed to 1 M, tensile strength was 20.7 ± 1.2 lbf and elongation to failure was 0.47 ± 0.02 in. CONCLUSION: The results demonstrated that a 6-month exposure to a physiologic range of ROS (1 mM) decreased tensile strength of PP mesh by 31 %. 1 mM and 0.1 M samples behaved similarly demonstrating properties of a quasi-crystalline nature. 1 M samples displayed qualities of extreme embrittlement. Scanning electron microscopy (SEM) observed fiber changes. 1 M meshes had features of brittle materials. Knowledge of changes in physical properties of PP meshes is useful for considerations for the development of a more biocompatible surgical mesh.