MiRNA-409-3p enhances cisplatin-sensitivity of ovarian cancer cells by blocking the autophagy mediated by Fip200.

Background: Efficacy of chemotherapy for ovarian cancer (OC) is usually affected by various factors,especially the chemoresistance of ovarian cancer cells. Downregulation of miR-409-3p has been found in a variety of tumors. However, the role of miR-409-3p in chemo-resistant OC cells still remains unknown. The aim of this study was to investigate the effect of miR-409-3p on cisplatin-resistant OC cells and to elucidate the mechanism by which enhances cisplatin-sensitivity of OC cells. Methods: Expression of miR-409-3p in OC cells was assessed by qRT-PCR. MTS and clone formation assays were used to validate cell proliferation. Flow cytometry was performed for apoptosis analysis. Western blot assay was used to assess the alterations of signaling pathway related proteins. BALB/c nude mouse xenograft model was used to evaluate the role of miR-409-3p in cisplatin-resistant OC cells in vivo. Results: We found that miR-409-3p was apparently downregulated in the OC cells compared with normal ovarian cells. Results also showed that compared with the cisplatinsensitive cells, in cisplatin-resistant cells, miR-409-3p was decreased with an obvious increasing autophagic activity. In addition, based on the bioinformatics analysis, miR-409-3p was supposed to bind with Fip200. Our results demonstrated that in miR-409-3p overexpression cells, significant decreases were seen in protein expression of Fip200 and autophagic activity, which might be caused by conjugation between overexpressed miR-409-3p and 3'-UTR in Fip200 mRNA. Moreover, under the miR-409-3p overexpression, we found that cisplatin-sensitive and cisplatin-resistant ovarian cancer cells were more sensitive to the chemotherapeutics, which could be reversed by Fip2000. Further, we found that chemosensitivity in tumor cells was augmented by miR-409-3p overexpression, and Fip200 acted as a key link in interrupting the chemotherapy-induced autophagy. Conclusions: Results mentioned above revealed that miR-409-3p can ameliorate cisplatin-sensitivity of ovarian cancer cells through blocking the autophagy mediated by Fip200.

Inhibition of hydrogen sulfide generation contributes to 1-methy-4-phenylpyridinium ion-induced neurotoxicity.

Reactive oxygen species (ROS) overproduction contributes to the neurotoxicity of 1-methy-4-phenylpyridinium ion (MPP(+)). Increasing studies have shown that hydrogen sulfide (H(2)S) is an endogenous antioxidant gas. We have hypothesized that MPP(+)-caused neurotoxicity may involve the imbalance of proportion to this endogenous protective antioxidant gas. The aim of this study is to evaluate whether MPP(+) disturbs H(2)S synthesis in PC12 cells, a clonal rat pheochromocytoma cell line, and whether disturbance of H(2)S generation induced by MPP(+) is an underlying mechanism of MPP(+)-induced neurotoxicity. We show that exposure of PC12 cells to MPP(+) causes a significant decrease in H(2)S generation and results in remarkable cell damage. We find that cystathionine-ß-synthetase (CBS) is catalyzed in PC12 cells to generate H(2)S, and that both expression and activity of CBS are inhibited by MPP(+) treatment. Exposure of sodium hydrosulfide (NaHS), a donor of H(2)S, extenuates MPP(+)-induced cytotoxicity and ROS accumulation in PC12 cells, while inhibition of CBS by amino-oxyacetate (AOAA) exacerbates the effects of MPP(+). These results indicate that MPP(+) neurotoxicity involves reduction of H(2)S production, which is caused by inhibition of CBS. This study provides novel insights into cell death observed in neurodegenerative disease such as Parkinson's disease.

The analyses of Mycoplasma pneumoniae antibody test results in patients with respiratory tract infection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the infection rate of Mycoplasma pneumoniae (MP) and age, sex and season.</p><p><b>METHODS</b>Passive agglutination assay was used to detect Mycoplasma pneumoniae antibodies (MP-Ab) in the serum of patients with respiratory tract infection, and MP-Ab test results in 2010 were analyzed.</p><p><b>RESULTS</b>The positive rates of 5 year test results were 30.10%; among the results, the positive rates of male and female patients were respectively 30.74% and 36.12%, the difference was statistically significant (P < 0.05); And every age group were significantly different (P < 0.001), among each group, the positive rate of 3-14 years old patients was the highest; the season was no significant difference in incidence rates; the patients of positive titer > 1:640 accounted for 10.18% of the patients.</p><p><b>CONCLUSION</b>MP infection is increasing year by year, children aged 3 to 14 has become the high-risk groups. Women are more susceptible to MP than the men and the chances of infection are throughout the year, but the most of the patients have a good prognosis.</p>