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Objective: To overcome the disadvantages of cisplatin, numerous platinum (Pt) complexes have been prepared. However, the anticancer activity and mechanism of Pt(II) complexed with 2-benzoylpyridine [Pt(II)- Bpy]: [PtCl2(DMSO)L] (DMSO = dimethyl sulfoxide, L = 2-benzoylpyridine) in cancer cells remain unknown. Methods: Pt(II)-Bpy was synthesized and characterized by spectrum analysis. Its anticancer activity and underlying mechanisms were demonstrated at the cellular, molecular, and in vivo levels. Results: Pt(II)-Bpy inhibited tumor cell growth, especially HepG2 human liver cancer cells, with a halfmaximal inhibitory concentration of 9.8±0.5μM, but with low toxicity in HL-7702 normal liver cells. Pt(II)- Bpy induced DNA damage, which was demonstrated through a marked increase in the expression of cleavedpoly (ADP ribose) polymerase (PARP) and gamma-H2A histone family member X and a decrease in PARP expression. The interaction of Pt(II)-Bpy with DNA at the molecular level was most likely through an intercalation mechanism, which might be evidence of DNA damage. Pt(II)-Bpy initiated cell cycle arrest at the S phase in HepG2 cells. It also caused severe loss of the mitochondrial membrane potential; a decrease in the expression of caspase-9 and caspase-3; an increase in reactive oxygen species levels; the release of cytochrome c and apoptotic protease activation factor; and the activation of caspase-9 and caspase-3 in HepG2 cells, which in turn resulted in apoptosis. Meanwhile, changes in p53 and related proteins were observed including the upregulation of p53, the phosphorylation of p53, p21, B-cell lymphoma-2-associated X protein, and NOXA; and the downregulation of B-cell lymphoma 2. Moreover, Pt(II)-Bpy displayed marked inhibitory effects on tumor growth in the HepG2 nude mouse model. Conclusion: Pt(II)-Bpy is a potential candidate for cancer chemotherapy.

Improved heat dissipation performance, by way of thermal management, is critical in many engineering applications. In this study, three types of silane coupling agents were used to modify aluminum nitride (AlN) powder for vat photopolymerization. The effect of silane coupling agents on the rheology, stability, and curing behavior were systematically studied. The results showed that, compared with two other types of silane coupling agents, one silane agent (KH570) had a larger positive effect on the rheology and stability of the AlN suspension, and the absorbance of the AlN powder increased after surface modification. In addition, the effects of different solid loadings on the curing behavior and CC double-bond conversion rate were systematically investigated. It was found that a higher solid loading resulted in a lower curing depth, cure width, and CC double-bond conversion rate. For the sintered AlN components with increased solid loading, the shrinkage decreased while both the flexural strength and thermal conductivity increased. In addition, the shrinkage in the Z-direction was higher than that in the X- and Y-directions. Scanning electron microscopy analysis showed that the mean grain size decreased with increasing solid loading. Furthermore, a heat dissipation performance evaluation system was designed to illustrate the heat transmission capacity of AlN ceramics. Simulation and experimental results showed that AIN ceramic parts with complex shapes achieved better heat-dissipation performance than those with simple shapes.

BackgroundEthnic health inequalities for males and females among the elderly have not yet been verified in multicultural societies in developing countries. The aim of this study was to assess the extent of disparities in health expectancy among the elderly from different ethnic groups using quality-adjusted life expectancy.DesignA cross-sectional community-based survey was conducted. A total of 6,511 rural elderly individuals aged ≥60 years were selected from eight different ethnic groups in the Guangxi Zhuang Autonomous Region of China and assessed for health-related quality of life (HRQoL). The HRQoL utility value was combined with life expectancy at age 60 years (LE60) data by using Sullivan's method to estimate quality-adjusted life expectancy at age 60 years (QALE60) and loss in quality-adjusted life years (QALYs) for each group.ResultsOverall, LE60and QALE60for all ethnic groups were 20.9 and 18.0 years in men, respectively, and 24.2 and 20.3 years in women. The maximum gap in QALE60between ethnic groups was 3.3 years in males and 4.6 years in females. The average loss in QALY was 2.9 years for men and 3.8 years for women. The correlation coefficient between LE60and QALY lost was −0.53 in males and 0.12 in females.ConclusionWomen live longer than men, but they suffer more; men have a shorter life expectancy, but those who live longer are healthier. Attempts should be made to reduce suffering in the female elderly and improve longevity for men. Certain ethnic groups had low levels of QALE, needing special attention to improve their lifestyle and access to health care.