However, the sulphuric acid treatment resulted in the degradation of the TBP-AE and the silica column fractionation resulted in the loss of BEH-TEBP and the elution of PBB-Acr and TBBPA-BME in the unsuitable fraction. High recoveries of DBE-DBCH (α+β), EHTBB, BTBPE, BEH-TEBP, and PBB-Acr were attributed to matrix effects, suggesting the need to use isotope-labelled surrogate standards of the target compounds. The optimisation of the silica column chromatography, GPC, and Partisil fractionation is described and discussed to afford easy implementation of the method. The method using GPC followed by Partisil fractionation is more efficient and more reproducible than the sulphuric acid-silica procedure. The application of this method to marine biota reference materials revealed the presence of relatively high concentrations of DBE-DBCH isomers and BDE-47 in fish samples. The method detection limits comply with the recommendations of the European Commission.The use of Chinese mitten crabs for human consumption is controversial due to their uptake of heavy metals, such as cadmium (Cd). We developed a formula for quantification of benefit and risk assessment (hazard quotient) for the intake of a product containing essential polyunsaturated fatty acids versus heavy metals. A total of 70 samples (2100 individuals) of crabs were collected from 6 representative basins in Jiangsu province to determine Cd levels. Cd levels ranged from 0.028 to 5.015 mg kg-1, and the levels among the basin regions were similar (p > 0.05). To determine the nutritional differences between crabs fed with iced trash fish and formulated feed, we conducted a comparative aquaculture experiment. We simulated the cultivation conditions of crabs in China and found that the nutritional content in the trash fish group (28.724 ± 2.301 mg kg-1) was significantly higher than in the formulated food group (19.278 ± 3.556 mg kg-1; p  0.05). The average hazard quotient of iced trash fish feed culture was 0.023 ± 0.019, compared with the formulated feed culture (0.034 ± 0.028). Formulated feed and iced trash fish produce similar results as culture food for the Chinese mitten crab. In terms of cadmium exposure risk, the appropriate daily consumption of crabs is less than eight. These data can help justify culture using formulated food and the sustainable development of the Chinese mitten crab industry.Arsenic exposure is well documented to cause serious health hazards, such as cardiovascular abnormalities, neurotoxicity and nephrotoxicity. In the present study, we intended to explore the role of bosentan, an endothelial receptor antagonist, against sodium arsenite-induced nephrotoxicity and hepatotoxicity in rats. Sodium arsenite (5 mg/kg, oral) was administered for 4 weeks to induce renal dysfunction in rats. Sodium arsenite intoxicated rats were treated with bosentan (50 and 100 mg/kg, oral) for 4 weeks. Arsenic led renal damage was demonstrated by significant increase in serum creatinine, urea, uric acid, potassium, fractional excretion of sodium, microproteinuria and decreased creatinine clearance in rats. Sodium arsenite resulted in marked oxidative stress in rat kidneys as indicated by profound increase in lipid peroxides, and superoxide anion generation alongwith decrease in reduced glutathione levels. Hydroxyproline assay highlighted arsenic-induced renal fibrosis in rats. Hematoxylin-eosin staining indicated glomerular and tubular changes in rat kidneys. Picrosirius red staining highlighted collagen deposition in renal tissues of arsenic treated rats. Immunohistological results demonstrated the reduction of renal eNOS expression in arsenic treated rats. Notably, treatment with bosentan attenuated arsenic-induced renal damage and resisted arsenic-led reduction in renal eNOS expression. In addition, sodium arsenite-induced alteration in hepatic parameters (serum aspartate aminotransferase, alanine transferase, alkaline phosphatase, bilirubin), oxidative stress and histological changes were abrogated by bosentan treatment in rats. Hence, we conclude that bosentan treatment attenuated sodium arsenite-induced oxidative stress, fibrosis and reduction in renal eNOS expression in rat kidneys. Moreover, bosentan abrogated arsenic led hepatic changes in rats.Panzhihua City, a typical eco-fragile region for agro-sylvo-pastoral industry in China, is located in the dry-hot valley of the Jinsha River, characterized by its big landform undulation, great elevation difference, uneven hydrothermal conditions, and complex geological structure.  https://www.selleckchem.com/products/bromelain.html  As a crucial ecological barrier in upper reaches of the Yangtze River, this area is abundant in water resources and mineral resources, such as vanadium and titanium. However, due to its over-development for nonnatural urban economy in the mining industry, agriculture, and animal husbandry, ecological problems are getting worse. Such problems as soil erosion and groundwater pollution have led obvious ecological degeneration in Panzhihua city. Therefore, for protecting the eco-environment and planning construction, it is significant to scientifically recognize that how eco-environment changes based on spatial-temporal, and how the driving mechanism affects Panzhihua city. Nowadays, there are some theories and methods that study eco-en fragility of Panzhihua City is steadily increasing from northwest to southeast. The overall ecological quality is moderate, and regional differences are obvious. Places of moderate vulnerability or above are distributed in central and eastern regions of frequent human activities; places of mild vulnerability or below are distributed in the regions of Yanbian County and Miyi County. (2) The comparison of the changing rates based on vulnerability levels is severe > potential > moderate > mild > slight. The overall vulnerability changes within a small trend, showing a balanced two-way transition state between adjacent vulnerability levels. The comprehensive index for overall ecological vulnerability decreases period by period. (3) The interactions between each two factors toward spatial differentiation and explanatory power by ecological vulnerability show a two-factor-enhanced relation, indicating that multiple factors form the ecological vulnerability of Panzhihua City.