Novel isobavachalcone derivatives induce apoptosis and necroptosis in human non-small cell lung cancer H1975 cells.

In this study, seventeen isobavachalcone (IBC) derivatives (1-17) were synthesised, and evaluated for their cytotoxic activity against three human lung cancer cell lines. Among these derivatives, compound 16 displayed the most potent cytotoxic activity against H1975 and A549 cells, with IC50 values of 4.35 and 14.21 µM, respectively. Compared with IBC, compound 16 exhibited up to 4.11-fold enhancement of cytotoxic activity on human non-small cell lung cancer H1975 cells. In addition, we found that compound 16 suppressed H1975 cells via inducing apoptosis and necroptosis. The initial mechanism of compound 16 induced cell death in H1975 cells involves the increasing of Bax/Bcl-2 ratio and Cyt C protein level, down-regulating of Akt protein level, and cleaving caspase-9 and -3 induced apoptosis; the up-regulation of RIP3, p-RIP3, MLKL, and p-MLKL levels induced necroptosis. Moreover, compound 16 also caused mitochondrial dysfunction, thereby decreasing cellular ATP levels, and resulting in excessive reactive oxygen species (ROS) accumulation.

[Comparison of Floating Chamber and Diffusion Model Methods for Measuring Methane Emissions from Inland Fish-Aquaculture Ponds].

Freshwater aquaculture ponds collectively cover a large area in southeast China. They are an important anthropogenic source of CH4 emissions, however current knowledge of CH4 emissions from aquaculture ponds is limited. During September 2017 and August 2018, two independent sampling campaigns of CH4 flux measurements over annual cycles were carried out in a fish-aquaculture pond in southeast China using a floating chamber and diffusion model methods for comparison. The purpose of this study is to investigate the variation of CH4 fluxes obtained from the fish-aquaculture pond, analyze the emission mechanisms, and amplify the CH4 emissions inventory. The diffusion model method can further quantify the contribution of diffusion transmission to CH4 emissions. The seasonal variations of CH4 fluxes measured by the two methods were similar, with higher CH4 fluxes appearing in summer and fall and lower CH4 fluxes appearing in spring and winter. CH4 fluxes measured by the floating chamber method and diffusion model method ranged from 0.14-3.13 mg·(m2·h)-1 and 0.04-1.41 mg·(m2·h)-1, respectively, and the respective average values were (0.86±0.30) mg·(m2·h)-1and (0.45±0.08) mg·(m2·h)-1. The CH4 fluxes were positively related to water temperature, dissolved organic carbon (DOC) and chemical oxygen demand (COD), but negatively related to the water dissolved oxygen (DO) concentration in the fish-aquaculture pond. CH4 fluxes calculated by diffusion model methods were 45% lower than those determined by the floating chamber methods over annual cycles. The result suggested that the floating chamber method is more suitable than the diffusion model method for measurements of CH4 fluxes in freshwater aquaculture ecosystems.