An aqueous rechargeable battery system is assembled by using metallic zinc and Na(0.95)MnO2 as the negative and positive electrodes, respectively. It is cheap and environmentally friendly, and its energy density is 78 Wh kg(-1). Its cycling performance is very good with only 8% capacity loss after 1000 cycles at 4 C between 1 and 2 V.

A nanocomposite of molybdenum trioxide (a-MoO 3 ) nanobelts coated with polypyrrole has been fabricated by a simple in situ polymerization route. The structure, morphology and electrochemical performance of the nanocomposite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and electrochemical measurements. It was found that the polypyrrole acted as a conducting matrix and a coating agent, which effectively improves the conductivity of the MoO 3 nanobelts and inhibits the dissolution of molybdenum ions during cycling. The supercapacitor based on the PPy@MoO 3 nanocomposite as the anode, activated carbon as the cathode and 0.5 M K 2 SO 4 aqueous solution as the electrolyte exhibits better rate capability as well as excellent cycling performance compared to the virginal MoO 3 .

BackgroundChemoresistance is one of the main obstacles to successful cancer therapy and is frequently associated with Multidrug resistance (MDR). Many different mechanisms have been suggested to explain the development of an MDR phenotype in cancer cells. One of the most studied mechanisms is the overexpression of P-glycoprotein (P-gp), which is a product of the MDR1 gene. Tumor cells often acquire the drug-resistance phenotype due to upregulation of the MDR1 gene. Overexpression of MDR1 gene has often been reported in primary gastric adenocarcinoma.MethodsThis study investigated the role of p38-MAPK signal pathway in vincristine-resistant SGC7901/VCR cells. P-gp and MDR1 RNA were detected by Western blot analysis and RT-PCR amplification. Mitgen-activated protein kinases and function of P-gp were demonstrated by Western blot and FACS Aria cytometer analysis. Ap-1 activity and cell apoptosis were detected by Dual-Luciferase Reporter Assay and annexin V-PI dual staining.ResultsThe vincristine-resistant SGC7901/VCR cells with increased expression of the multidrug-resistance 1 (MDR1) gene were resistant to P-gp-related drug and P-gp-unrelated drugs. Constitutive increases of phosphorylated p38-MAPK and AP-1 activities were also found in the drug-resistant cells. Inhibition of p38-MAPK by SB202190 reduced activator protein-1 (AP-1) activity and MDR1 expression levels and increased the sensitivity of SGC7901/VCR cells to chemotherapy.ConclusionActivation of the p38-MAPK pathway might be responsible for the modulation of P-glycoprotein-mediated and P-glycoprotein-unmediated multidrug resistance in the SGC7901/VCR cell line.