Mechanisms mediating the inhibitory effects of quercetin against phthalates-induced testicular oxidative damage in rats / 南方医科大学学报

OBJECTIVE@#To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.@*METHODS@#Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.@*RESULTS@#Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).@*CONCLUSION@#Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.

Application of nonlinear autoregressive neural network in predicting incidence tendency of hemorrhagic fever with renal syndrome / 中华流行病学杂志

Objective To explore the prospect of nonlinear autoregressive neural network in fitting and predicting the incidence tendency of hemorrhagic fever with renal syndrome (HFRS),in the mainland of China.Methods Monthly reported case series of HFRS in China from 2004 to 2013 were used to build both ARIMA and NAR neural network models,in order to predict the monthly incidence of HFRS in China in 2014.Fitness and prediction on the effects of these two models were compared.Results For the Fitting dataset,MAE,RMSE and MAPE of the ARIMA model were 148.058,272.077 and 12.678％ respectively,while the MAE,RMSE and MAPE of NAR neural network appeared as 119.436,186.671 and 11.778％ respectively.For the Predicting dataset,MAE,RMSE and MAPE of the ARIMA model appeared as 189.088,221.133 and 21.296％,while the MAE,RMSE and MAPE of the NAR neural network as 119.733,151.329 and 11.431％ respectively.Conclusion The NAR neural network showed better effects in fitting and predicting the incidence tendency of HFRS than using the traditional ARIMA model,in China.NAR neural network seemed to have strong application value in the prevention and control of HFRS.