The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) releas...The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(II) is significantly higher than that of the cells treated with Fe(III) (P<0.05). Fe(II) at a concentration >1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(III). LDH release investigation suggests that Fe(II) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(II) were higher than those of the cells treated with Fe(III), although both of them increased with raising iron supply levels. The results indicate that both Fe(II) and Fe(III) could reduce the cellular antioxidase gene expression at high levels.展开更多
Effects of SO2 in ambient air on the performance and durability of solid oxide fuel cell（SOFC） cathode were evaluated by galvanostatic measurement. Comparison between two cathode materials was made to consider the c...Effects of SO2 in ambient air on the performance and durability of solid oxide fuel cell（SOFC） cathode were evaluated by galvanostatic measurement. Comparison between two cathode materials was made to consider the cathode degradation mechanisms. The degradation performance is associated with a slow decomposition of the La0.6Sr0.4Co0.2Fe0.8O3（LSCF） due to the segregation of strontium oxide. Negligible deterioration for （La0.7Sr0.3）MnO3 （LSM） cathode was caused by SO2 poisoning under a current density of 200 mA/cm2. Metal sulphate formation may explain a slight deterioration under increasing high the concentration of SO2. It was verified that the poisoning mechanism for the two cathode materials resulted from the gradual decomposition of the cathode materials.展开更多
基金the International Cooperative Project from the Ministry of Science and Technology of China (No. 2006DFA31030)the Bureau of Science and Technology of Zhejiang Province (No. 2006C32019)+1 种基金 HarvestPlus-China (No. 8022)the Program for Changjiang Scholars and Innovative Research Team in University of China (No. IRT0536)
文摘The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(II) is significantly higher than that of the cells treated with Fe(III) (P<0.05). Fe(II) at a concentration >1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(III). LDH release investigation suggests that Fe(II) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(II) were higher than those of the cells treated with Fe(III), although both of them increased with raising iron supply levels. The results indicate that both Fe(II) and Fe(III) could reduce the cellular antioxidase gene expression at high levels.
基金Supported by the National Natural Science Foundation of China(No.50872041)the Research Funds of Industrial Technology Research and Development Projects of Jilin Province, China(No.JF2012C024)+1 种基金the Natural Science Foundation of Jilin Province,China(No.201215109)the Science and Technology Research Projects of Education Department of Jilin Province, China(No.2011205)
文摘Effects of SO2 in ambient air on the performance and durability of solid oxide fuel cell（SOFC） cathode were evaluated by galvanostatic measurement. Comparison between two cathode materials was made to consider the cathode degradation mechanisms. The degradation performance is associated with a slow decomposition of the La0.6Sr0.4Co0.2Fe0.8O3（LSCF） due to the segregation of strontium oxide. Negligible deterioration for （La0.7Sr0.3）MnO3 （LSM） cathode was caused by SO2 poisoning under a current density of 200 mA/cm2. Metal sulphate formation may explain a slight deterioration under increasing high the concentration of SO2. It was verified that the poisoning mechanism for the two cathode materials resulted from the gradual decomposition of the cathode materials.
