RESUMEN
Janus Pd/SiO2 nanocomposite particles (NCPs) were successfully synthesized through a combination of the sol-gel process of tetramethoxysilane in inverse miniemulsions and in situ reduction of Pd salts via a gas diffusion process of hydrazine. The formation of Pd nanoparticles (NPs) was verified by X-ray diffraction. The Janus morphology of the Pd/SiO2 NCPs was confirmed by microscopic observation. The Pd/SiO2 NCPs displayed a mesoporous structure. The content of Pd NPs in the NCPs could be conveniently adjusted by the K2PdCl4 loading. A formation mechanism of the Janus Pd/SiO2 NCPs was proposed. The mesoporous Janus Pd/SiO2 NCPs show good catalytic activity toward the reduction of p-nitrophenol with NaBH4.
RESUMEN
The overall outcomes for patients with advanced liver cancer are far from satisfactory, and the development of more effective therapeutic strategies for liver cancer is required. Sulforhodamine blue and colony formation assays were performed to detect the proliferation of liver certain cancer cells, including HepG2 and Hep3B. Western blotting was also preformed to detect the expression of indicated proteins, including cleaved-caspase-3, cleaved-poly (ADP-ribose) polymerase, dual-specificity tyrosine phosphorylation kinase 1A (DYRK1A), PARP-1/2, GAPDH, myeloid cell leukemia-1, phosphorylated-AKT (Ser473), caspase-3, α-tubulin and AKT. PI staining was used to detect cell death. In the present study, DYRK1A knockdown significantly enhanced the anti-liver cancer effect of regorafenib in vitro. Furthermore, DYRK1A inhibitor harmine together with regorafenib provided synergistic anti-liver cancer activity by suppressing cell proliferation. In addition, harmine significantly enhanced regorafenib-induced cell death in liver cancer cells. It has been reported that AKT signaling is activated in regorafenib-resistant cancer cells and plays a crucial role in the regulation of cellular sensitivity to regorafenib. In the present study, AKT was activated in regorafenib-treated cells, and harmine could suppress the activation of AKT and reinforce the anti-cancer effects of regorafenib via regulating AKT in liver cancer cells. These data indicated that harmine enhanced the anti-cancer effects of regorafenib on suppressing cell proliferation and inducing apoptosis in liver cancer cells via regulating the activation of AKT, and harmine plus regorafenib may be a potential therapeutic regimen for treating patients with liver cancer.
RESUMEN
In the present study, superparamagnetic Fe3O4/poly(N-isopropyl acrylamide) nanocomposites were synthesized by one-step inverse miniemulsion copolymerization of N-isopropyl acrylamide and N,N'-methylene diacrylamide. The loading of Fe3O4 nanoparticles in the nanocomposites was 27 wt%, and the saturation moment of the nanocomposites was 12.4 emu x g(-1). Fe3O4 nanoparticles were prepared through a coprecipitation method. The amount of stabilizer (poly(acrylic acid)) significantly influenced the size and size distribution of the Fe3O4 nanoparticles, and, therefore, their magnetic properties. Superparamagnetism of the Fe3O4 nanoparticles was preserved in the nanocomposites. The effects of synthetic parameters on the particle properties, namely surfactant loading, concentration of ferrofluid, type of lipophobe and initiator, and amount of cross-linker were investigated. Nanocomposites of Fe3O4/poly(N-isopropyl acrylamide) displayed a guava-like morphology, which they could retain after being redispersed in polar solvents.
RESUMEN
Ag/TiO2 nanocomposites were prepared through combination of a sol-gel process of a titanium precursor in inverse miniemulsions and in situ reduction of silver ions in the "nanoreactors". The morphological investigation shows that Ag nanoparticles are mainly located on the surface of TiO2 nano-supports because of the fast reduction rate of Ag ions by hydrazine. Ag/TiO2 nanocomposites with amorphous or anatase TiO2 phase displayed high visible-light catalytic activity for degradation of Rhodamine B. The photoactivity of Ag/anatase TiO2 nanocomposites could be influenced by the Ag content that could be conveniently tuned by the loading of silver salts. The influence of the loading of silver salts on the particle properties of the Ag/TiO2 nanocomposites was investigated systematically.