Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of th...Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of the molecules,using anoxia/hypoglycemia-induced cell injury model and thereby to explore the structure-effect relationship thereto.Methods The cell injury model was established by HEK293 cells cultured in vitro with Na2S2O3 plus sugar-free Earle's fluid as incubation medium.Cell survival rate(CSR),total antioxidant capacity(TAC),SOD and LDH levels were determined.The effect intensity of the 3 flavonoids was compared by means of IC50,the concentration required to achieve 50% inhibition of the changes in the above indices in injured cells.Results Q,I and R all concentration-dependently elevated CSR,TAC and SOD and reduced LDH level.The all of IC50s for the above indices were ranked in order of IC50,Q<IC50,I<IC50,R,namely,the effect intensity should be Q>I >R.Conclusions The 3 structurally similar flavoloids all have significant and concentration-dependent anti-free radical and cyto-protective effects with the intensity being in order of aglycone>monoglucoside>diglucoside;the substitution of-OH by sugar group at C-3 position of flavoloids and increase in the sugar-substituent number are associated with the effect intensity reduced;namely,the intensity of these effects of flavonoids is negatively related the substutution by sugar group at C-3 position.展开更多
It was reported that hemispheric corrosion occurred in copper tubes in an acetic acid environment. When hemispheric corrosion occurred, corrosion could easily progress if water then flowed into the copper pipe, and co...It was reported that hemispheric corrosion occurred in copper tubes in an acetic acid environment. When hemispheric corrosion occurred, corrosion could easily progress if water then flowed into the copper pipe, and countermeasures were needed. Therefore, we studied the copper corrosion caused by acetic acid. The present work investigated the relationship between the corrosion form of copper and acetic acid concentration using phosphorous-deoxidized copper, and reported that hemispherical corrosion was observed at acetic acid concentrations of 0.01 to 1 vol.% (0.002 to 0.2 mol·L<sup>-1</sup>) in the immersion test. In this study, the effects of acetic acid and phosphate on copper corrosion were examined using oxygen-free copper in immersion tests. The results suggested that different concentrations of phosphate in acetic acid solutions and the presence or absence of acetic acid and phosphate affected the corrosion of copper, resulting in different corrosion forms and corrosion progress.展开更多
AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope ...AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. METHODS: LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation,such as diameters of arterioles and venules,velocity of RBCs in venules,leukocyte rolling,adhesion and emigration,free radicals released from post-capillary venules,FITC- albumin leakage and mast cell degranulation,were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile,the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils,and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. RESULTS: The continuous infusion with LPS resulted in a number of responses in microcirculation,including a significant increase in the positive region of venulestained with Monastral blue B,rolling and adhesion of leukocytes,production of oxygen radical in venular wall,albumin efflux and enhanced mast cell degranulation in vivo,all of which,except for the leukocyte rolling,were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils,and the expression of ICAM-1 in HUVECs were increased by exposure to LPS,and they were attenuated by compound Danshen injection. CONCLUSION: These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance.展开更多
AIM:To investigate the effect of total salvianolic acid(TSA) on ischemia-reperfusion(I/R)-induced rat mesenteric microcirculatory dysfunctions.METHODS:Male Wistar rats were randomly distributed into 5 groups(n = 6 eac...AIM:To investigate the effect of total salvianolic acid(TSA) on ischemia-reperfusion(I/R)-induced rat mesenteric microcirculatory dysfunctions.METHODS:Male Wistar rats were randomly distributed into 5 groups(n = 6 each):Sham group and I/R group(infused with saline),TSA group,TSA + I/R group and I/R + TSA group(infused with TSA,5 mg/kg per hour).Mesenteric I/R were conducted by a ligation of the mesenteric artery and vein(10 min) and subsequent release of the occlusion.TSA was continuously infused either starting from 10 min before the ischemia or 10 min after reperfusion.Changes in mesenteric microcirculatory variables,including diameter of venule,velocity of red blood cells in venule,leukocyte adhesion,free radicals released from venule,albumin leakage and mast cell degranulation,were observed through an inverted intravital microscope.Meanwhile,the expression of adhesion molecules CD11b/CD18 on neutrophils was evaluated by flow cytometry.Ultrastructural evidence of mesenteric venules damage was assessed after microcirculation observation.RESULTS:I/R led to multiple responses in mesenteric post-capillary venules,including a significant increase in the adhesion of leukocytes,production of oxygen radicals in the venular wall,albumin efflux and enhanced mast cell degranulation in vivo.All the I/R-induced manifestations were significantly reduced by pre-or post-treatment with TSA,with the exception that the I/R-induced increase in mast cell degranulation was inhibited only by pre-treatment with TSA.Moreover,preor post-treatment with TSA significantly attenuated the expression of CD11b/CD18 on neutrophils,reducing the increase in the number of caveolae in the endothelial cells of mesentery post-capillary venules induced by I/R.CONCLUSION:The results demonstrated that TSA protects from and ameliorates the microcirculation disturbance induced by I/R,which was associated with TSA inhibiting the production of oxygen-free radicals in the venular wall and the expression of CD11b/CD18 on neutrophils.展开更多
为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化...为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化物歧化酶（SOD）活性及丙二醛（MDA）的含量.结果表明,模拟高原低氧暴露4,24 h 可引起胃肠组织中线粒体呼吸链四种复合酶的活性明显降低（P 〈0.01）,而在72 h 后恢复为接近对照组水平（P 〉0.05）.低氧处理后胃肠组织的线粒体 SOD 活性明显低于对照组（P 〈0.01）,MDA 含量高于对照组（P 〈0.01）.因此,高原低氧可抑制大鼠胃肠线粒体呼吸链组分的酶活性,该效应可能与低氧的直接作用和由此引起的氧化应激损伤有关.展开更多
文摘Objective To comparatively study anti-free radical and cytoprotective effects of quercetin(Q)and its monoglucoside isoquercetin(I),diglucoside rutin(R),which differs only in glycosyl-substitution at C-3 position of the molecules,using anoxia/hypoglycemia-induced cell injury model and thereby to explore the structure-effect relationship thereto.Methods The cell injury model was established by HEK293 cells cultured in vitro with Na2S2O3 plus sugar-free Earle's fluid as incubation medium.Cell survival rate(CSR),total antioxidant capacity(TAC),SOD and LDH levels were determined.The effect intensity of the 3 flavonoids was compared by means of IC50,the concentration required to achieve 50% inhibition of the changes in the above indices in injured cells.Results Q,I and R all concentration-dependently elevated CSR,TAC and SOD and reduced LDH level.The all of IC50s for the above indices were ranked in order of IC50,Q<IC50,I<IC50,R,namely,the effect intensity should be Q>I >R.Conclusions The 3 structurally similar flavoloids all have significant and concentration-dependent anti-free radical and cyto-protective effects with the intensity being in order of aglycone>monoglucoside>diglucoside;the substitution of-OH by sugar group at C-3 position of flavoloids and increase in the sugar-substituent number are associated with the effect intensity reduced;namely,the intensity of these effects of flavonoids is negatively related the substutution by sugar group at C-3 position.
文摘It was reported that hemispheric corrosion occurred in copper tubes in an acetic acid environment. When hemispheric corrosion occurred, corrosion could easily progress if water then flowed into the copper pipe, and countermeasures were needed. Therefore, we studied the copper corrosion caused by acetic acid. The present work investigated the relationship between the corrosion form of copper and acetic acid concentration using phosphorous-deoxidized copper, and reported that hemispherical corrosion was observed at acetic acid concentrations of 0.01 to 1 vol.% (0.002 to 0.2 mol·L<sup>-1</sup>) in the immersion test. In this study, the effects of acetic acid and phosphate on copper corrosion were examined using oxygen-free copper in immersion tests. The results suggested that different concentrations of phosphate in acetic acid solutions and the presence or absence of acetic acid and phosphate affected the corrosion of copper, resulting in different corrosion forms and corrosion progress.
文摘AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. METHODS: LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation,such as diameters of arterioles and venules,velocity of RBCs in venules,leukocyte rolling,adhesion and emigration,free radicals released from post-capillary venules,FITC- albumin leakage and mast cell degranulation,were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile,the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils,and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. RESULTS: The continuous infusion with LPS resulted in a number of responses in microcirculation,including a significant increase in the positive region of venulestained with Monastral blue B,rolling and adhesion of leukocytes,production of oxygen radical in venular wall,albumin efflux and enhanced mast cell degranulation in vivo,all of which,except for the leukocyte rolling,were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils,and the expression of ICAM-1 in HUVECs were increased by exposure to LPS,and they were attenuated by compound Danshen injection. CONCLUSION: These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance.
基金Supported by Production of New Medicine Program of Ministry of Science and Technology of the People's Republic of China,No.2008ZX09401
文摘AIM:To investigate the effect of total salvianolic acid(TSA) on ischemia-reperfusion(I/R)-induced rat mesenteric microcirculatory dysfunctions.METHODS:Male Wistar rats were randomly distributed into 5 groups(n = 6 each):Sham group and I/R group(infused with saline),TSA group,TSA + I/R group and I/R + TSA group(infused with TSA,5 mg/kg per hour).Mesenteric I/R were conducted by a ligation of the mesenteric artery and vein(10 min) and subsequent release of the occlusion.TSA was continuously infused either starting from 10 min before the ischemia or 10 min after reperfusion.Changes in mesenteric microcirculatory variables,including diameter of venule,velocity of red blood cells in venule,leukocyte adhesion,free radicals released from venule,albumin leakage and mast cell degranulation,were observed through an inverted intravital microscope.Meanwhile,the expression of adhesion molecules CD11b/CD18 on neutrophils was evaluated by flow cytometry.Ultrastructural evidence of mesenteric venules damage was assessed after microcirculation observation.RESULTS:I/R led to multiple responses in mesenteric post-capillary venules,including a significant increase in the adhesion of leukocytes,production of oxygen radicals in the venular wall,albumin efflux and enhanced mast cell degranulation in vivo.All the I/R-induced manifestations were significantly reduced by pre-or post-treatment with TSA,with the exception that the I/R-induced increase in mast cell degranulation was inhibited only by pre-treatment with TSA.Moreover,preor post-treatment with TSA significantly attenuated the expression of CD11b/CD18 on neutrophils,reducing the increase in the number of caveolae in the endothelial cells of mesentery post-capillary venules induced by I/R.CONCLUSION:The results demonstrated that TSA protects from and ameliorates the microcirculation disturbance induced by I/R,which was associated with TSA inhibiting the production of oxygen-free radicals in the venular wall and the expression of CD11b/CD18 on neutrophils.
文摘为研究低氧环境对大鼠胃肠线粒体呼吸链复合物活性和自由基代谢的影响,将雄性 Wister 大鼠分别暴露于模拟5000 m 海拔进行4,24,72 h 的低氧处理.取小肠和胃组织,采用分光光度法测定线粒体呼吸链酶复合物 CⅠ~CⅣ活性,检测线粒体超氧化物歧化酶（SOD）活性及丙二醛（MDA）的含量.结果表明,模拟高原低氧暴露4,24 h 可引起胃肠组织中线粒体呼吸链四种复合酶的活性明显降低（P 〈0.01）,而在72 h 后恢复为接近对照组水平（P 〉0.05）.低氧处理后胃肠组织的线粒体 SOD 活性明显低于对照组（P 〈0.01）,MDA 含量高于对照组（P 〈0.01）.因此,高原低氧可抑制大鼠胃肠线粒体呼吸链组分的酶活性,该效应可能与低氧的直接作用和由此引起的氧化应激损伤有关.
