Zuo Jin Wan (ZJW), a typical traditional Chinese medicine (TCM) formula, has been identified to have anticancer activity in recent studies. In this study, we determined the underlying mechanism of ZJW in the reversal effect of multidrug resistance on colorectal cancer in vitro and in vivo. Our results showed that ZJW significantly enhanced the sensitivity of chemotherapeutic drugs in HCT116/L-OHP, SGC7901/DDP, and Bel/Fu MDR cells. Moreover, combination of chemotherapy with ZJW could reverse the drug resistance of HCT116/L-OHP cells, increase the sensitivity of HCT116/L-OHP cells to L-OHP, DDP, 5-Fu, and MMC in vitro, and inhibit the tumor growth in the colorectal MDR cancer xenograft model. ICP-MS results showed that ZJW could increase the concentration of chemotherapeutic drugs in HCT116/L-OHP cells in a dose-dependent manner. Furthermore, we showed that ZJW could reverse drug resistance of colorectal cancer cells by decreasing P-gp level in vitro and in vivo, which has been represented as one of the major mechanisms that contribute to the MDR phenotype. Our study has provided the first direct evidence that ZJW plays an important role in reversing multidrug resistance of human colorectal cancer and may be considered as a useful target for cancer therapy.

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The catalytic performance in heterogeneous catalytic reactions consisting of solid reactants is strongly dependent on the nanostructure of the catalysts. Metal-oxides core-shell (MOCS) nanostructures have potential to enhance the catalytic activity for soot oxidation reactions as a result of optimizing the density of active sites located at the metal-oxide interface. Here, we report a facile strategy for fabricating nanocatalysts with self-assembled Pt@CeO-rich core-shell nanoparticles (NPs) supported on three-dimensionally ordered macroporous (3DOM) CeZrOvia the in situ colloidal crystal template (CCT) method. The nanostructure-dependent activity of the catalysts for soot oxidation were investigated by means of SEM, TEM, H-TPR, XPS, O-isothermal chemisorption, soot-TPO and so on. A CeO-rich shell on a Pt core is preferentially separated from CeZrO precursors and could self-assemble to form MOCS nanostructures. 3DOM structures can enhance the contact efficiency between catalysts and solid reactants (soot). Pt@CeO-rich core-shell nanostructures can optimize the density of oxygen vacancies (O) as active sites located at the interface of Pt-CeZrO. Remarkably, 3DOM Pt@CeO-rich/CeZrO catalysts show super catalytic performance and strongly nanostructure-dependent activity for soot oxidation in the absence of NO and NO. For example, the T of the 3DOM Pt@CeO-rich/CeZrO catalyst is lowered down to 408 °C, and the reaction rate of the 3DOM Pt@CeO-rich/CeZrO catalyst (0.12 μmol g s) at 300 °C is 4 times that of the 3DOM Pt/CeZrO catalyst (0.03 μmol g s). The structures of 3DOM CeZrO-supported Pt@CeO-rich core-shell NPs are decent systems for deep oxidation of solid reactants or macromolecules, and this facile technique for synthesizing catalysts has potential to be applied to other element compositions.

Three-dimensionally ordered macroporous (3DOM) Mn x Ce1–x Oδ oxides with different ratios of Mn to Ce were successfully synthesized by colloidal crystal template (CCT) method, and 3DOM Pt/Mn0.5Ce0.5Oδ with varied Pt loadings were prepared by in situ ethylene glycol (EG) reduction method. 3DOM Mn x Ce1–x Oδ supports exhibited well-defined 3DOM nanostructure, and Pt nanoparticles (NPs) with 1–2 nm size were evenly dispersed on the inner walls of uniform macropores. Among 3DOM Mn x Ce1–x Oδ catalysts, 3DOM Mn0.5Ce0.5Oδ showed excellent catalytic activity for soot combustion; i.e., T 50 is 358 °C and S CO2 m is 94.2%. 3DOM Pt/Mn0.5Ce0.5Oδ catalysts exhibited higher activity than 3DOM Mn x Ce1–x Oδ and 3 wt % Pt/Mn0.5Ce0.5Oδ showed the highest catalytic activity for soot combustion (T 50 is 342 °C and S CO2 m is 96.7%). Macropores effect, synergistic effects between Mn and Ce, and synergistic effects between Pt and Mn0.5Ce0.5Oδ support are contributed to high catalytic activities of as-prepared catalysts.

Developing platinum catalysts highly active for hydrocarbon combustion at low temperatures is crucial but yet challenging, since platinum may convert into inert PtO x in oxidizing atmospheres and deactivates during catalytic combustion. In this article, a Pt@TiO x /TiO2 catalyst with platinum nanoparticles decorated by amorphous TiO x overlayers was synthesized via a strong metal–support interaction (SMSI)-related strategy. The Pt-TiO x electronic interaction stabilized reactive Pt0 sites during reactions, resulting in outstanding activities and high stability for C3H8 and C3H6 combustion. The influences of sulfatescommon byproducts forming on catalysts applied for automobile exhaust purificationwere studied by monitoring the platinum states, the hydrocarbon adsorption behavior, and the catalytic performance of sulfated Pt@TiO x /TiO2 with in situ DRIFTS. It is suggested that the sulfates promoted C3H8 combustion via heterolytic C–H bond activation on Ptδ+–(SO4)δ− couples, while C3H6 combustion was disfavored on the sulfated catalyst because of inhibited O2 activation.

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