Background Donor-pretreatment with ulinastatin may influence the liver graft during cold preservation. The aim of this research was to determine whether pretreatment of donor liver with Ulinastatin can attenuate cold ...Background Donor-pretreatment with ulinastatin may influence the liver graft during cold preservation. The aim of this research was to determine whether pretreatment of donor liver with Ulinastatin can attenuate cold preservation injury,and to explore the mechanism by which Ulinastatin affects the donor liver graft.Methods One hundred and forty-four Wistar rats were divided into the Ulinastatin treatment group （T group） pretreated with Ulinastatin 50 000 U/kg and control group （C group） treated with 0.9% normal saline via peritoneal injection prior to the anesthetization. After the abdominal cavity was opened and perfused with cold Ringer＇s lactate solution, the liver was harvested. The harvested liver was preserved in cold Ringer＇s lactate solution for 0, 2, 6, 24 hours, at which time the liver tissue was sampled for determination of dry weight and wet weight, Na＋-K＋-ATPase and Ca2＋-ATPase activity, lactic acid dehydrogenase （LDH） activity, lactic acid and malondialdehyde levels. Light microscopy and electron microscopy were used to observe liver morphology. The liver cold-preservation solution was taken for measurement of aspartate aminotransferase （AST） and alanine transaminase （ALT） levels. Correlation between ATPase activity and lactic acid level was analyzed by SPSS 13.0 for Windows.Results The morphology in the T group had improved cell boundaries vs. The C group at each time point. Dry weight to wet weight in the T group was lower than in the C group at 6 hours （P 〈0.05）, but the difference was not significant at 24 hours. ALT levels in the T group were lower than that in the C group at 6 hours （P 〈0.05） and 24 hours （P 〈0.01）. AST levels in the T group were lower than those in the C group at 2 hours （P〈0.05）, 6 hours （P 〈0.01） and 24 hours （P 〈0.01）.Na＋-K＋-ATPase activity in the T group was higher than in the C group and the mean difference between two groups was significant at 0 hour （P 〈0.05） and 2 hours （P 〈0.05）. Ca2＋展开更多
During the production of the inner walls of ovens,pit defects were formed on the surface of the enamel layer that was enameled on the cold-rolled steel via electrostatic powder spraying and sintering.The paper elabora...During the production of the inner walls of ovens,pit defects were formed on the surface of the enamel layer that was enameled on the cold-rolled steel via electrostatic powder spraying and sintering.The paper elaborates on the microstructure and element distribution of the enamel-steel interface and the enamel layer.Optical microscopy,scanning electron microscopy,and energy-dispersive spectroscopy were adopted to investigate the microstructure of a longitudinal section of the defect,and the pit-forming causes were analyzed.The results show that rusty spots lead to pit defects.During high-temperature firing,there is an inadequate fusion and reaction between iron oxides of the rusty spots and the enamel glaze.The rusty spots are closely related to pretreatment process;thus,to avoid their occurrence,electrostatic powder spraying and sintering should be performed timely after forming,degreasing,and thorough drying of the metal sheets.展开更多
基金This research was supported by a grant from the Provincial Natural Science Foundation of Gansu, China （No. 3ZS051-A25- 104）.
文摘Background Donor-pretreatment with ulinastatin may influence the liver graft during cold preservation. The aim of this research was to determine whether pretreatment of donor liver with Ulinastatin can attenuate cold preservation injury,and to explore the mechanism by which Ulinastatin affects the donor liver graft.Methods One hundred and forty-four Wistar rats were divided into the Ulinastatin treatment group （T group） pretreated with Ulinastatin 50 000 U/kg and control group （C group） treated with 0.9% normal saline via peritoneal injection prior to the anesthetization. After the abdominal cavity was opened and perfused with cold Ringer＇s lactate solution, the liver was harvested. The harvested liver was preserved in cold Ringer＇s lactate solution for 0, 2, 6, 24 hours, at which time the liver tissue was sampled for determination of dry weight and wet weight, Na＋-K＋-ATPase and Ca2＋-ATPase activity, lactic acid dehydrogenase （LDH） activity, lactic acid and malondialdehyde levels. Light microscopy and electron microscopy were used to observe liver morphology. The liver cold-preservation solution was taken for measurement of aspartate aminotransferase （AST） and alanine transaminase （ALT） levels. Correlation between ATPase activity and lactic acid level was analyzed by SPSS 13.0 for Windows.Results The morphology in the T group had improved cell boundaries vs. The C group at each time point. Dry weight to wet weight in the T group was lower than in the C group at 6 hours （P 〈0.05）, but the difference was not significant at 24 hours. ALT levels in the T group were lower than that in the C group at 6 hours （P 〈0.05） and 24 hours （P 〈0.01）. AST levels in the T group were lower than those in the C group at 2 hours （P〈0.05）, 6 hours （P 〈0.01） and 24 hours （P 〈0.01）.Na＋-K＋-ATPase activity in the T group was higher than in the C group and the mean difference between two groups was significant at 0 hour （P 〈0.05） and 2 hours （P 〈0.05）. Ca2＋
文摘During the production of the inner walls of ovens,pit defects were formed on the surface of the enamel layer that was enameled on the cold-rolled steel via electrostatic powder spraying and sintering.The paper elaborates on the microstructure and element distribution of the enamel-steel interface and the enamel layer.Optical microscopy,scanning electron microscopy,and energy-dispersive spectroscopy were adopted to investigate the microstructure of a longitudinal section of the defect,and the pit-forming causes were analyzed.The results show that rusty spots lead to pit defects.During high-temperature firing,there is an inadequate fusion and reaction between iron oxides of the rusty spots and the enamel glaze.The rusty spots are closely related to pretreatment process;thus,to avoid their occurrence,electrostatic powder spraying and sintering should be performed timely after forming,degreasing,and thorough drying of the metal sheets.
