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Background: Extensive data suggest that exposure to cigarette smoke can induce pulmonary epithelial barrier dysfunction. However, the effects of cigarette smoke on the nasal epithelial barrier are still unclear. Here, we investigated the consequence and mechanism of cigarette smoke on the nasal epithelial barrier. Methods: Sprague Dawley rats were exposed to cigarette smoke for 3 or 6 months, and changes in inflammatory markers and nasal barrier function were evaluated. Moreover, underlying mechanisms were explored. Finally, normal human bronchial epithelial cells were cultured with or without tumor necrosis factor-alpha (TNF-α) in vitro, and the levels of continuity and tight junction–associated proteins were measured. Results: In vivo experiments showed that the nasal mucosal barrier function of rats exposed to cigarette smoke was disturbed. Indeed, proteins associated with tight junctions were decreased, and the levels of inflammatory factors, such as IL-8, IL-6, and TNF-α, were dramatically increased in comparison to those of control animals. In vitro, TNF-α was shown to disrupt the continuity of proteins associated with tight junctions and to downregulate the expression of these proteins in bronchial epithelial cells. Conclusions: We found that cigarette smoke disrupted the nasal mucosal barrier, and the extent of the damage was correlated with the duration of cigarette smoke exposure. We showed that TNF-α can disrupt the continuity and attenuate the expression of tight junction proteins in human bronchial epithelial cells. Therefore, cigarette smoke may induce nasal epithelial barrier dysfunction through TNF-α. [ABSTRACT FROM AUTHOR]

5α-reductase inhibitors (5-ARI) are widely employed for the treatment of benign prostatic hyperplasia. It has been noted that 5-ARI exhibit the potential to attenuate the risk of prostate cancer, but consistent agreement has not been achieved. Moreover, the effect of 5-ARI on cancer-specific mortality and progression of prostate cancer remains unclear. Therefore, the goal of the current meta-analysis was to elucidate the impact of 5-ARI on the incidence and progression of prostate cancer. We searched for all studies assessing the effect of 5-ARI on risk of prostate cancer in PubMed, Embase, Medline, and Cochrane Library databases. Pooled relative risk (RR) and corresponding 95% confidence intervals (CIs) were accepted to evaluate the association between 5-ARI and the risk of prostate cancer. Synthetic results implied that subjects who accepted 5-ARI compared with the placebo group experienced a distinctly weakened overall incidence of prostate cancer (RR = 0.74; 95% CI: 0.66–0.82; P < 0.001). Subgroup analyses further revealed that 5-ARI reduction of the incidence of prostate cancer was limited to low-grade (Gleason score 2–6; RR = 0.68; 95% CI: 0.57–0.81; P < 0.001) and intermediate-grade tumors (Gleason score 7; RR = 0.81; 95% CI: 0.67–0.97; P = 0.023), but not high-grade tumors (Gleason score >7; RR = 1.19; 95% CI: 0.98–1.43; P = 0.069). The results also showed that 5-ARI treatment did not significantly alter prostate cancer-specific mortality (RR = 1.0; 95% CI: 0.95–1.05; P = 0.916). In addition, it was worth noting that 5-ARI treatment acted in a protective role that presented a dramatic benefit to delay the progression of low-risk tumors (RR = 0.58; 95% CI: 0.43–0.78; P < 0.001). [ABSTRACT FROM AUTHOR]

In order to improve the evaluation accuracy of the mine strata pressure bumping danger, a related study was conducted based on the inversion technology of the 3D ground stress field. Taking No. I panel of Guojiahe Mine as a study object, based on the analysis on the geological tectonic features, coal and rock physical mechanics test and the mine ground stress measurement, according to the multiple linear regression principle, a numerical simulation inversion was conducted on the 3D ground stress field. The ground stress of the 3D ground stress field within the study region was obtained. Under the comprehensive consideration on the tectonic stress and mining stress influences, a macro evaluation on the mine strata pressure bumping danger from No. I panel and the accurate evaluation on the mine strata pressure bumping danger in a local section was realized. There were 11 strong mine strata pressure bumping dangerous zones and 5 medium mine strata pressure bumping dangerous zones divided. [ABSTRACT FROM AUTHOR]

Using TAW-2000 servo testing machine and Germany VallenAMSY-6 acoustic emission signal acquisition system, the acoustic emission characteristics of marble under uniaxial compression, constant amplitude cyclic loading and unloading and tiered cyclic loading and unloading were studied. In addition, using Fast Fourier Transformation (FFT),the acoustic emission spectrum characteristics of marble under uniaxial compression and Kaiser points and Felicity points in the process of tiered cyclic loading and unloading were analyzed. Test results show that: Firstly, main frequency locate mainly in two areas, which are the regions less than 200 kHz and near 300 kHz, and the main frequency varies from low frequency to high frequency and the amplitude of main frequency declines on the whole with the increasing stress. Secondly, a new indicator to reflect acoustic emission waveform information, namely SF (secondary frequency) -by-MF (main frequency) ratio α, was put forward and in the process of uniaxial compression test SF (secondary frequency)-by-MF (main frequency) shows ascendant trend. Thirdly, the change of main frequency at Kaiser point and Felicity point is not obvious and the SF (secondary frequency)-by-MF (main frequency) ratio at Felicity point is higher than the one at Kaiser point in the hierarchical cyclic loading and unloading process. At last, by regarding AE (Acoustic Emission) counts at the point of stress in the second cycle whose stress is equal to the peak stress of first cycle as the "significant increased" scale of Kaiser effect, obvious Felicity effect is showed. [ABSTRACT FROM AUTHOR]

To master the precursor information of burst coal bursting failure is the bottleneck problem to scientifically forecast rock burst, and the precursor information study on acoustic emission of coal with different outburst proneness under stress loading is one of the important ways for rock burst forecasting. The research results presented in this paper show that, as the level of coal's outburst proneness increasing, the counts of coal vibration and energy of acoustic emission were concentrated at high stress region, with the time proportion of the elastic stage increasing while time proportion of plastic stage decreasing. The width of the main frequency channel changed little, tending to a concentration. The strength of the main frequency channel increased with varying degrees during the elastic stage, plastic stage and breaking stage, the growth of the strength of frequency increasing as the coal's outburst proneness becoming larger. The stress increased as the b-value decreasing, tending to close to breaking strength of the coal. [ABSTRACT FROM AUTHOR]

Studies have demonstrated the detrimental effects of overt hyperthyroidism on sexual functioning.Here,we comprehensively reviewed the studies that focused on the association between overt hyperthyroidism and erectile dysfunction (ED).After the systematic searching for relevant studies,we find that overt hyperthyroidism is significantly associated with the high risk of ED.The prevalence of ED in patients with hyperthyroidism ranges from 3.05% to 85%,while that in general population is 2.16% to 33.8%.A study reported that the erectile functioning of the hyperthyroidism patients was improved (International Index of Erectile Function:22.1±6.9 vs. 25.2±5.1) after the achievement of euthyroidism.The underlying mechanism of the increase in the risk of ED by overt hyperthyroidism might be correlated to the dysfunction of hypothalamus-pituitary-thyroid axis,dysregulation of sex hormones,abnormal expression of thyroid hormone receptors,and psychiatric or psychological disturbances (e.g.,depression,anxiety,and irritability).Since limited clinical trials have been conducted,additional well-designed cohorts with sizable samples are warranted to elucidate the evidence and mechanism of hyperthyroidism predisposing to ED.The present review indicates that overt hyperthyroidism and the risk of ED are associated,which reminds the clinicians should assess the thyroid stimulating hormone in hyperthyroidism patients presenting with ED,especially in those without positive conventional laboratory findings for causing ED.