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@#Objective To investigate the effect of caloric restriction(CR)on myocardial ischemia/reperfusion injury(MI/RI)in mice and its mechanism.Methods C57 mice were randomly divided into normal diet group(AL group,free feeding)and CR group(diet decreased by 10% every 2 weeks)for 8 weeks and monitored for weight changes.Each group was divided into sham operation group and MI/RI group,total 4 groups,AL + Sham group,AL + I/R group,CR + Sham group and CR + I/R group).The left anterior descending coronary artery was ligated for 30 minutes and then reperfused for 24 hours in mice of MI/RI group and mice in Sham group were only threaded but not ligated.The mice were determined for myocardial ischemia and infarct size by Evans blue/TTC staining,observed for the pathology of myocardium by HE staining,determined for the activities of lactate dehydrogenase(LDH),superoxide dismutase(SOD)and the contents of creatine kinase-MB(CK-MB)and malondialdehvde(MDA)in myocardium by the corresponding kits,determined for serum levels of IL-1β and IL-18 by ELISA and detected for the expression of pyroptosis-associated proteins in myocardium by Western blot.Results After 8weeks,the weights of mice in CR group[(24.54 ± 0.41)g]were significantly lower than those in AL group[(31.46 ±0.25)g](t = 14.34,P<0.05).Compared with those in AL + I/R group,the area of myocardial ischemia in CR + I/R group showed no significant difference(t = 0.783 0,P>0.05),while the area of myocardial infarction decreased significantly(t = 7.250,P<0.01);The myocardial arrangement was relatively neat,and the degree of pathological changes was obviously reduced;LDH activity,CK-MB and MDA contents decreased significantly(t = 4.331,2.875 and 5.343 respectively,each P<0.05),while SOD activity increased significantly(t = 4.211,P<0.05);Serum levels of IL-1β and IL-18 decreased significantly(t = 3.375 and 4.266 respectively,each P<0.05);The expression levels of nod-like receptor protein 3(NLRP3),gasdermin D(GSDMD),apoptosis-associated speckle-like protein(ASC)and caspase-1 significantly decreased(t = 3.412,3.420,3.480 and 2.585 respectively,each P<0.05).Conclusion CR alleviated MI/RI in mice,and its mechanism was related to the inhibition of cardiac pyroptosis.
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Objective To investigate the inducing effects and related pathways of selenium dioxide ( SeO2 ) on the apoptosis in 2 human cervical carcinoma cell lines of high risk HPV subtypes .Methods HeLa (HPV-18-positive) and Caski (HPV-16-positive) cells were incubated with different concentrations of SeO 2 for 24 h respectively.Mor-phological changes of HeLa and Caski cells were observed under inverted optical microscope ;cell proliferation and activity were examined by MTT assay;flow cytometry was employed to detect the cell apoptosis;the expressions of apoptosis-related proteins caspase-3 and p53 in cervical carcinoma cell lines were determined by Western blot analysis;the effects of SeO 2 on apoptosis-related miRNA LET-7a expression was detected by stem-loop reverse tran-scription-polymerase chain reaction (RT-PCR).Results Cell morphology was obviously changed in vitro.Cells be-came rounded and shrunken .SeO2 markedly inhibited cell proliferation and viability in a dose-dependent manner in both cell lines; In HeLa cells the inhibitory effects induced by 7.5-30 μmol/L of SeO 2 were significant ( P<0.05);The inhibitory effects on Caski were statistical significant (P<0.05) even with low concentrations of SeO 2. The apoptosis induced by SeO 2 increased dose-dependently in cervical carcinoma cell lines , which were higher in Caski.SeO2 up-regulated the apoptosis-related proteins in cervical carcinoma cell lines .The expressions of caspase-3 and p53 in HeLa cells both significantly increased as compared with control group (P<0.05), and peaked at the concentration of 7.5 μmol/L.Treated with higher concentrations ( 7.5-30 μmol/L ) of SeO 2 , the expression on Caski cells increased significantly ( P<0.05 ) .SeO 2 induced of expression of apoptosis-related miRNA LET-7a both in HeLa cells and Caski cells with statistical meanings ( P<0.05 );the effects reached its peak at the concentration of 7.5 μmol/L bothly.Conclusions SeO2 shows anti-tumor properties via apoptosis pathway by up-regulating the expressions of apoptosis-related proteins caspase-3, the mechanisms of can be potentially explained by p 53 and LET-7a in cervical cancer cell lines.The apoptosis-inducing effect of SeO2 is more sensitive in HPV16+cell line compared with HPV18+cell line.
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Background Rhizoctonia solani (teleomorph: Thanatephorus cucumeris) is one of the most important pathogens of rice (Oryza sativa L.) that causes severe yield losses in all rice-growing regions. Sclerotia, formed from the aggregation of hyphae, are important structures in the life cycles of R. solani and contain a large quantity of polysaccharides, lipids, proteins and pigments. In order to extract high-quality total RNA from the sclerotia of R. solani, five methods, including E.Z.N.A.™ Fungal RNA Kit, sodium dodecyl sulfate (SDS)-sodium borate, SDS-polyvinylpyrrolidone (PVP), guanidinium thiocyanate (GTC) and modified Trizol, were compared in this study. Results The electrophoresis results showed that it failed to extract total RNA from the sclerotia using modified Trizol method, whereas it could extract total RNA from the sclerotia using other four methods. Further experiments confirmed that the total RNA extracted using SDS-sodium borate, SDS-PVP and E.Z.N.A.™ Fungal RNA Kit methods could be used for RT-PCR of the specific amplification of GAPDH gene fragments, and that extracted using GTC method did not fulfill the requirement for above-mentioned RT-PCR experiment. Conclusion It is concluded that SDS-sodium borate and SDS-PVP methods were the better ones for the extraction of high-quality total RNA that could be used for future gene cloning and expression studies, whereas E.Z.N.A.™ Fungal RNA Kit was not taken into consideration when deal with a large quantity of samples because it is expensive and relatively low yield.