Protective effects of taurine against endotoxin-induced acute liver injury after hepatic ischemia reperfusion.

Hepatic ischemia reperfusion (HIR) not only results in liver injury, but also leads to endotoxemia, which aggravates HIR-induced liver injury and dysfunction, or even causes liver failure. Taurine has been shown to protect organs from ischemia reperfusion or endotoxin by its anti-oxidant and anti-inflammatory activities. The aim of this study was to investigate whether taurine could attenuate endotoxin-induced acute liver injury after HIR. Wistar rats subjected to 30 min of hepatic ischemia followed by reperfusion and lipopolysaccharide (LPS) (0.5 mg/kg) administration, exhibited liver dysfunction (elevated serum levels of ALT, AST and LDH) and hepatic histopathological alteration. The serum levels of TNF-alpha and production of myeloperoxidase (MPO) and malondialdehyde (MDA) in liver tissues and apoptosis of hepatocytes were also increased after the combination of HIR and LPS. However, pre-administration of taurine protected livers from injury induced by the combination of HIR + LPS as the histological score, apoptotic index, MPO activity and production of MDA in liver tissues, and serum levels of AST, ALT, LDH and TNF-alpha, were significantly reduced. The expression of caspase-3, Fas and Fas ligand was upregulated in homogenates of livers from rats subjected to HIR and LPS, and this elevated expression could be inhibited by taurine. In summary, the results further emphasize the potential utilization of taurine in protecting livers against endotoxin-induced injury especially after HIR, by its anti-inflammatory, anti-oxidative and anti-apoptotic activities.

Physical models and limits of radionuclides for decorative building materials.

In the past, the external exposure dose model for soil (the soil's physical model) was used to calculate the doses of decorative building materials because there was no materials model. In this paper, physical models are proposed to calculate the absorbed dose rates in air from decorative building materials by Monte Carlo simulation with the EGSnrc code. The physical models of this paper greatly differ from physical models for soil. The good agreement between simulations and measured absorbed dose rate in indoor air indicates that the results obtained by the Monte Carlo simulations are realistic. The absorbed dose rates in air calculated by physical models for soil are much higher than the measured dose rates. According to the reports of UNSCEAR 2000 and ICRP 1999, the limits of radionuclides in some kinds of decorative building materials were deduced by using the physical models for materials presented in our work. The limits of every kind of decorative building material from our work are different.