目的:研究新合成产物乙酰半胱氨酸镁盐-甘草酸环状样二聚体(acetylcysteine magnesiumglycyrrhizin fine antipode dimers,GFA-NAC·Mg)治疗大鼠肝纤维化的效果。方法:25%四氯化碳(CCl4)制备大鼠肝纤维化模型,GFA-NAC·Mg按25...目的:研究新合成产物乙酰半胱氨酸镁盐-甘草酸环状样二聚体(acetylcysteine magnesiumglycyrrhizin fine antipode dimers,GFA-NAC·Mg)治疗大鼠肝纤维化的效果。方法:25%四氯化碳(CCl4)制备大鼠肝纤维化模型,GFA-NAC·Mg按25、50、100mg/kg剂量每日分别腹腔注射进行肝纤维化治疗,给药8周后处死大鼠,用肝纤维化网格染色观察肝纤维化情况,ELISA法测定血清羟脯氨酸(Hyp)和肝组织丙二醛(MDA)、超氧化物歧化酶(SOD)、转化生长因子-β1(TGF-β1)、血小板衍生生长因子(PDGF)。结果:大鼠肝组织病理结果显示其肝纤维化处于Ⅲ-Ⅳ期;与模型组比较,GFA-NAC·Mg治疗后血清Hyp明显降低;肝组织抗氧化指标SOD显著升高,MDA明显下降;肝纤维化指标TGF-β1、PDGF在组织含量下降;GFA-NAC·Mg各组网格染色显示肝纤维化好转。结论:GFA-NAC·Mg对肝纤维化大鼠有较好实验治疗作用,可能通过抑制PDGF和TGF-β1的表达而实现。展开更多
AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jej...AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jejunal APP mRNA levels,liver and jejunal glutathione concentrations were measured before and one,three and seven days after turpentine injection in 4 groups of control,protein-restricted,protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height,and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil,glutamine supplementation restored villus heights and glutathione concentration (3.24 ± 1.05 vs 1.72 ± 0.46 μmol/g tissue,P < 0.05) in the jejunum,whereas in the liver glutathione remained low. Glutamine markedly increased jejunal α1-acid glycoprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. CONCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model.展开更多
The interaction between citrate capped silver nanoparticles and two different thiols, mercaptohexanol （MH） and cysteine, was investigated. The thiols interacted with silver nanoparticles in a significantly contrasti...The interaction between citrate capped silver nanoparticles and two different thiols, mercaptohexanol （MH） and cysteine, was investigated. The thiols interacted with silver nanoparticles in a significantly contrasting manner. With MH, a sparingly soluble silver（1） thiolate complex AgSRm （Rm = -（CH2）6OH） was formed on the silver nanoparticle surface. Cyclic voltammograms and UV-vis spectra were used to infer that the AgSRm complex on the nanoparticle surface undergoes a phase transition to give a mixture of AgSRm and Ag2S-like complexes. In contrast, when silver nanoparticles were exposed to cysteine, the citrate cap- ping agent on the silver nanoparticles was replaced by cysteine to give cysteine capped nanoparticles. As cysteine capped nanoparticles form, the electrochemical data displayed a decrease in oxidative peak charge but the UV-vis spectra showed a constant signal. Therefore, cysteine capped nanoparticles were suggested to have either inactivated the silver surface or else pro- moted detachment from the electrode surface.展开更多
文摘目的:研究新合成产物乙酰半胱氨酸镁盐-甘草酸环状样二聚体(acetylcysteine magnesiumglycyrrhizin fine antipode dimers,GFA-NAC·Mg)治疗大鼠肝纤维化的效果。方法:25%四氯化碳(CCl4)制备大鼠肝纤维化模型,GFA-NAC·Mg按25、50、100mg/kg剂量每日分别腹腔注射进行肝纤维化治疗,给药8周后处死大鼠,用肝纤维化网格染色观察肝纤维化情况,ELISA法测定血清羟脯氨酸(Hyp)和肝组织丙二醛(MDA)、超氧化物歧化酶(SOD)、转化生长因子-β1(TGF-β1)、血小板衍生生长因子(PDGF)。结果:大鼠肝组织病理结果显示其肝纤维化处于Ⅲ-Ⅳ期;与模型组比较,GFA-NAC·Mg治疗后血清Hyp明显降低;肝组织抗氧化指标SOD显著升高,MDA明显下降;肝纤维化指标TGF-β1、PDGF在组织含量下降;GFA-NAC·Mg各组网格染色显示肝纤维化好转。结论:GFA-NAC·Mg对肝纤维化大鼠有较好实验治疗作用,可能通过抑制PDGF和TGF-β1的表达而实现。
文摘AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jejunal APP mRNA levels,liver and jejunal glutathione concentrations were measured before and one,three and seven days after turpentine injection in 4 groups of control,protein-restricted,protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height,and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil,glutamine supplementation restored villus heights and glutathione concentration (3.24 ± 1.05 vs 1.72 ± 0.46 μmol/g tissue,P < 0.05) in the jejunum,whereas in the liver glutathione remained low. Glutamine markedly increased jejunal α1-acid glycoprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. CONCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model.
基金supported by the National Research Foundation Singapore under its National Research Foundation(NRF)Environmental and Water Technologies(EWT)PhD Scholarship Programme and administered by the Environment and Water Industry Programme Office(EWI)supported by a Marie Curie Intra European Fellowshipfunding from the European Union’s Seventh Framework Programme(FP/2007-2013)/ERC Grant Agreement n.[320403]
文摘The interaction between citrate capped silver nanoparticles and two different thiols, mercaptohexanol （MH） and cysteine, was investigated. The thiols interacted with silver nanoparticles in a significantly contrasting manner. With MH, a sparingly soluble silver（1） thiolate complex AgSRm （Rm = -（CH2）6OH） was formed on the silver nanoparticle surface. Cyclic voltammograms and UV-vis spectra were used to infer that the AgSRm complex on the nanoparticle surface undergoes a phase transition to give a mixture of AgSRm and Ag2S-like complexes. In contrast, when silver nanoparticles were exposed to cysteine, the citrate cap- ping agent on the silver nanoparticles was replaced by cysteine to give cysteine capped nanoparticles. As cysteine capped nanoparticles form, the electrochemical data displayed a decrease in oxidative peak charge but the UV-vis spectra showed a constant signal. Therefore, cysteine capped nanoparticles were suggested to have either inactivated the silver surface or else pro- moted detachment from the electrode surface.
