The aim of this study was to explore the relationship between biomechanical properties and the occurrence of pelvic organ prolapse (POP) through analysis on biomechanical properties of vaginal tissue. The biopsy specimens were obtained from 43 patients undergoing transvaginal hysterectomy, who were assigned into premenopausal POP, postmenopausal POP, premenopausal control and postmenopausal control groups. Tissue specimens were biomechanically assessed by a purpose-built tissue puller system, and stress-strain curves were digitally recorded. The Young's modulus, Poisson's ratio, maximum elongation, maximum fracture of vaginal tissue were 9.45 +/- 0.70, 0.43 +/- 0.01, 1.50 +/- 0.02, 0.60 +/- 0.02 in premenopausal POP group; 12.10 +/- 1.10, 0.39 +/- 0.01, 1.14 +/- 0.05, 0.27 +/- 0.03 in postmenopausal POP group; 6.65 +/- 1.48, 0.46 +/- 0.01, 1.68 +/- 0.11, 0.79 +/- 0.05 in premenopausal control group and 10.26 +/- 1.10, 0.42 +/- 0.01, 1.37 +/- 0.04, 0.42 +/- 0.03 in postmenopausal control group. There was significant difference in biomechanical properties between premenopausal POP group and premenopausal control group (p < 0.01). There was significant difference in biomechanical properties between postmenopausal POP group and postmenopausal control group (p < 0.01). Biomechanical properties in POP group were significantly lower than that in control group, suggesting that degeneration of biomechanical properties in pelvic support construction might lead to the occurrence of POP.

The prevalence of OAB in chinese women is lower than that of most reports in Occidental women, and increases with advancing age. Many potential risk factors increase the occurrence of OAB.

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We present a theoretical study of a new hybrid material, nanostructured polymeric nitrogen, where a polymeric nitrogen chain is encapsulated in a carbon nanotube. The electronic and structural properties of the new system are studied by means of ab initio electronic structure and molecular dynamics calculations. Finite temperature simulations demonstrate the stability of this nitrogen phase at ambient pressure and room temperature using carbon nanotube confinement. This nanostructured confinement may open a new path towards stabilizing polynitrogen or polymeric nitrogen at ambient conditions.

Objective. Numerous epidemiological studies have linked diabetes mellitus (DM) with an increased risk of developing Alzheimer's disease (AD). However, whether or not diabetic encephalopathy shows AD-like pathology remains unclear. Research Design and Methods. Forebrain and hippocampal volumes were measured using stereology in serial coronal sections of the brain in streptozotocin- (STZ-) induced rats. Neurodegeneration in the frontal cortex, hypothalamus, and hippocampus was evaluated using Fluoro-Jade C (FJC). Aβ aggregation in the frontal cortex and hippocampus was tested using immunohistochemistry and ELISA. Dendritic spine density in the frontal cortex and hippocampus was measured using Golgi staining, and western blot was conducted to detect the levels of synaptophysin. Cognitive ability was evaluated through the Morris water maze and inhibitory avoidant box. Results. Rats are characterized by insulin deficiency accompanied with polydipsia, polyphagia, polyuria, and weight loss after STZ injection. The number of FJC-positive cells significantly increased in discrete brain regions of the diabetic rats compared with the age-matched control rats. Hippocampal atrophy, Aβ aggregation, and synapse loss were observed in the diabetic rats compared with the control rats. The learning and memory of the diabetic rats decreased compared with those of the age-matched control rats. Conclusions. Our results suggested that aberrant metabolism induced brain aging as characterized by AD-like pathologies.