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Oridonin, an ent-kaurene diterpenoid isolated from the traditional Chinese herb Rabdosia rubescens, has been reported to be a potent cytotoxic agent against a wide array of cancer cells. However, its effect on human nasopharyngeal carcinoma (NPC) cells has not been well investigated. The present study aimed to explore the anti-tumour effect of oridonin in NPC cells and its underlying mechanisms. Cell viability was examined by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyl-tetrazolium bromide assay and colony formation assay. Apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and expression of apoptosis-related proteins were analysed by flow cytometry with propidium iodide staining, JC-1 staining, DCFH-DA staining, and Western blot analysis, respectively. The results showed that oridonin concentration-dependently inhibited the cell viability, decreased the colony formation, and enhanced the apoptotic rate in NPC cells. Further, oridonin-induced apoptosis was mediated by the mitochondrial pathway in NPC cells, which was confirmed by the loss of MMP, downregulation of anti-apoptotic Bcl-2 family protein Mcl-1 and Bcl-2, upregulation of pro-apoptotic Bcl-2 family member Bax, and activation of caspase-3 and PARP. Notably, the augmented ROS generation played an essential role in oridonin-induced apoptosis in NPC cells, as the apoptosis-inducing effect was attenuated by ROS scavenger N-acetyl-L-cysteine. These results indicate that oridonin triggers apoptosis through the ROSmediated mitochondrial pathway in NPC cells. This study supports oridonin to be an interesting candidate drug for the treatment of human NPC. [ABSTRACT FROM AUTHOR]

The ESA Aeolus mission aims to measure wind profiles from space. In preparation for launch we aim to assess the expected bias in retrieved winds from the Mie and Rayleigh channel signals induced by atmospheric heterogeneity. Observation biases are known to be detrimental when gone undetected in Numerical Weather Prediction (NWP). Aeolus processing equipment should therefore be prepared to detect heterogeneous atmospheric scenes and take measures, e.g., reject or reduce the weight of observations when used in NWP. Radiosondes provide the wind vector at about 10m resolution. We present a method to simulate co-located cloud and aerosol optical properties from radiosonde observations. We show that cloud layers can be detected along the radiosonde path from radiosonde measured relative humidity and temperature. A parameterization for aerosol backscatter and extinction along the radiosonde path is presented based on a climatological aerosol backscatter profile and radiosonde relative humidity. The resulting high-resolution database of atmospheric wind and optical properties serves as input for Aeolus wind simulations. It is shown that Aeolus wind error variance grows quadratically with bin size and the wind-shear over the bin. Strong scattering aerosol or cloud layers may cause biases exceeding 1 ms-1 for typical tropospheric conditions and 1 km Mie channel bin size, i.e., substantially larger than the mission bias requirement of 0.4 ms-1. Advanced level-2 processing of Aeolus winds including estimation of atmosphere optical properties is needed to detect regions with large heterogeneity, potentially yielding biased winds. Besides applicable for Aeolus the radiosonde database of co-located high-resolution wind and cloud information can be used for the validation of atmospheric motion wind vectors (AMV) or to correct their height assignment errors. [ABSTRACT FROM AUTHOR]

Mercury pollution in the Second Songhua River (SSR) was serious in the last century due to effluent from a chemical corporation. Effects of riverine self-purification on mercury removal were studied by comparing monitoring data of mercury concentrations varieties in water, sediment, and fish in the past, about 30 years. The present work suggested that a river of such a size like the SSR possessed the potential ability to recover from mercury pollution under the condition that mercury sources were cut off, though it needs a very long time, which might be several decades or even a century of years. During the 30 years with no effluent containing mercury input, total mercury (T-Hg) of water and sediment in some typical segments, mostly near the past effluent outlet, had decreased radically but still higher than the background values, though the decrease amplitudes were over 90% compared with that in 1975. T-Hg had decreased by more than 90% in most fishes, but some were still not suitable for consumption. Methylmercury concentrations (MeHg) of water, sediment, and fish were higher or close to the background levels in 2004. In the coming decades, the purification processes in the SSR would be steady and slow for a long period. [ABSTRACT FROM AUTHOR]