ABSTRACT
The biomass multi-elements self-doped TiO2was synthesized simultaneously by ultrasonic irradiation assisted sol-gel method, and characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRS), Fourier transform infrared (FT-IR) spectroscopy, and photoluminescence (PL). The characterization results showed that,multiple elements, C, N, P, Cl and K, were doped in the composite TiO2. Compared with pure TiO2,the band gap of the composite catalyst was narrowed by 0.21 eV, and possessed more surface hydroxyl radical and active sites, lower recombination rate of photo-generated carriers, higher crystallinity and higher specific surface area. The photocatalytic ability of the composite catalyst was studied,using methylene blue (MB) as target pollutant. The experimental results showed that, under visible light irradiation,the degradation efficiency of methylene blue was up to 98% after photocatalytic reaction for two hours by the composite catalyst.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the reversal effect of dihydromyricetin(DMY) on drug resistance of K562/A02 cells to adriamycin and explore its possible mechanism.</p><p><b>METHODS</b>K562 and K562/A02 cells were treated with DMY (5, 10, 20, 40, 60, 80 and 100 mg/L) and ADM (100-0.05 mg/L) for 48 h. The viability of K562 cells and K562/A02 cells was tested and the reversal effect of DMY on drug resistance of K562/A02 cells to adriamycin was analyzed by MTT. The relative concentration of ADM in cells was measured by flow cytometry. Protein expressions of drug resistance related genes including P-glycoprotein (P-gp), multidrug resistance associated protein 1 (MRP1), glutathione transferase π (GSTπ) and BCL-2 were measured by Western Blot.</p><p><b>RESULTS</b>The proliferation of K562 and K562/A02 cells was significantly decreased by DMY in dose-dependent manner as compared with control group (r1=0.37, r2=0.38). The ICof ADM on K562 and K562/A02 cells were 71.23±6.51 and 72.88±5.49 mg/L respectively. DMY (5, 10 and 20 mg/L) was low cytotoxicity. DMY (5, 10 and 20 mg/L) enhanced the sensitivity of K562/A02 cells to ADM in dose-dependent manner (r1=-0.62, r2=-0.71) and the reversal multiples was from 1.38 to 28.591. The relative concentrations of ADM in K562/A02 of DMY (5, 10 and 20 mg/L) group cells were significantly increased in dose-dependent manner compared with the control group (r=0.34). Compared with the control group, the expressions of drug resistance related protein P-gp, MRP1, GSTπ and BCL-2 were significantly decreased in dose-dependent manner in DMY (5, 10 and 20 mg/L) group (r1=-0.41, r2=-0.37, r3=-0.58, r=-0.46). Compared with the ADM group, the protein expressions of drug resistance related genes P-gp, MRP1, GSTπ and BCL-2 in DMY (5, 10 and 20 mg/L)+ADM group were significantly decreased in dose-dependent manner (r1=-0.55, r2=-0.41, r3 =-0.38, r4=-0.44).</p><p><b>CONCLUSION</b>DMY enhances the sensitivity of K562/A02 cells to ADM, its mechanism may be related with decrease of P-gp, MRP1, GSTπ and BCL-2 expressions.</p>