RESUMO
In this work, a free-standing flexible composite electrode was prepared by vacuum filtration method with LiFePO4, graphene and nanofibrillated cellulose (NFC). Compared with the pure LiFePO4 electrode, the resulting flexible composite (LiFePO4/graphene/NFC) electrode showed excellent mechanical flexibility, and possessed an enhanced initial discharge capacity of 151â¯mAâ¯h/g (0.1 C) and a good capacity retention rate with only 5% loss after 60â¯cycles due to suitable electrolyte wettability at the interface. Furthermore, the NFC and graphene formed a three-dimensional conductive framework, which provided high-speed electron conduction in the composite and reduced electrode polarization during charging-discharging processes. Moreover, the composite electrode could endure bending tests up to 1000 times, highlighting preferable mechanical strength and durability. These results demonstrated that the as-fabricated electrodes could be applied as flexible electrodes with an embedded power supply.
RESUMO
BACKGROUND: MicroRNAs (miRNAs) play key roles in tumor development and progression. The aim of this study was to explore the expression levels of miR-34a and miR-217 in hepatocellular carcinoma (HCC) and to further investigate the clinicopathological and prognostic value of miR-34a and miR-217. METHODS: The expression levels of miR-34a and miR-217 were evaluated using quantitative real-time PCR (qRT-PCR). Associations between these miRNAs expression and clinicopathological features were analyzed. Survival rate was determined with Kaplan-Meier and statistically analyzed with the log-rank method between groups. RESULTS: We found that miR-34a expression was significantly downregulated in HCC tissues (P<0.05). Reduced expression of miR-34a was associated with vascular invasion, and advanced TNM stage (P<0.05). Kaplan-Meier revealed that reduced expression of miR-34a was associated with poor overall survival (log-rank test, P<0.05). We found that miR-217 was downregulated in HCC tissues. Decreased expression of miR-217 was remarkably correlated vascular invasion, and advanced TNM stage (P<0.05). Kaplan-Meier analysis and log-rank test showed that HCC patients with low expression of miR-217 was associated with shorter overall survival than patients with high expression (log-rank test, P<0.05). CONCLUSIONS: Our data showed that downregulation of miR-34a and miR-217 was associated with HCC progression and both of them may act as tumor suppressor in HCC.