目的:研究党参水提物对D-半乳糖致衰老模型小鼠肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性和线粒体结构的影响,探讨党参在延缓衰老中的作用及其机制。方法:将100只小鼠随机分为正常对照组、模型对照组和党参水提物低、中、高剂量组5组。除...目的:研究党参水提物对D-半乳糖致衰老模型小鼠肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性和线粒体结构的影响,探讨党参在延缓衰老中的作用及其机制。方法:将100只小鼠随机分为正常对照组、模型对照组和党参水提物低、中、高剂量组5组。除正常对照组外,其余4组每日每只小鼠颈背部皮下注射5%D-半乳糖溶液,注射量为0.025 m L/g,正常对照组注射同体积生理盐水。党参低、中、高剂量组每日上午依次按相当于生药量5,10,15 g/kg个剂量给致衰老小鼠灌服党参水煎液,与造模同步,连续服药42 d。采用分光光度法测定肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性,电镜观察肝、肾线粒体结构损伤。结果:党参水提物中、高剂量组小鼠肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性均升高,其中高剂量组的肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性与模型对照组对比,差别有统计学意义(P<0.01)。党参水提物高剂量组小鼠肝、肾线粒体结构异常变化明显改善,党参水提物高剂量组肝、肾线粒体损伤程度显著低于模型对照组(P<0.05)。结论:高剂量的党参水提物能通过某种机制减缓或阻止线粒体结构的异常改变,改善或维持其正常功能的执行,起到延缓衰老的作用,具体的机制还有待进一步的研究。展开更多
TiO2-coated activated carbon surface （TAs） composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow （AY） was investigated under UV radiation to es...TiO2-coated activated carbon surface （TAs） composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow （AY） was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate.展开更多
Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding sy...Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively.展开更多
Vanadium compounds show potential in diabetes and cancer treatment, although the toxicity remains a great concern. Previous studies have shown that vanadium-induced oxidative stress affecting mitochondrial function is...Vanadium compounds show potential in diabetes and cancer treatment, although the toxicity remains a great concern. Previous studies have shown that vanadium-induced oxidative stress affecting mitochondrial function is intensively responsible for the toxicity. In this work, we investigated the effects of the vanadium compounds sodium metavanadate （NaVO3） and vanadyl acetylacetonate （VO（acac）2） on mitochondrial ROS generation and respiratory complex activities. The experimental results showed that vanadium compounds affected the ROS generation and complex activities in different patterns depending on the chemical species. NaVO3 inhibited mitochondrial complexes Ⅰ and Ⅱ activities and stimulated ROS generation at low concentration range; while VO（acac）2 promoted complex Ⅱ activity but resulted in electron leakage from the complex Ⅰ-involved pathway. The present results provide new evidence for understanding the toxicity of antidiabetic vanadium compounds.展开更多
文摘目的:研究党参水提物对D-半乳糖致衰老模型小鼠肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性和线粒体结构的影响,探讨党参在延缓衰老中的作用及其机制。方法:将100只小鼠随机分为正常对照组、模型对照组和党参水提物低、中、高剂量组5组。除正常对照组外,其余4组每日每只小鼠颈背部皮下注射5%D-半乳糖溶液,注射量为0.025 m L/g,正常对照组注射同体积生理盐水。党参低、中、高剂量组每日上午依次按相当于生药量5,10,15 g/kg个剂量给致衰老小鼠灌服党参水煎液,与造模同步,连续服药42 d。采用分光光度法测定肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性,电镜观察肝、肾线粒体结构损伤。结果:党参水提物中、高剂量组小鼠肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性均升高,其中高剂量组的肝、肾线粒体呼吸链复合体Ⅰ、Ⅳ酶活性与模型对照组对比,差别有统计学意义(P<0.01)。党参水提物高剂量组小鼠肝、肾线粒体结构异常变化明显改善,党参水提物高剂量组肝、肾线粒体损伤程度显著低于模型对照组(P<0.05)。结论:高剂量的党参水提物能通过某种机制减缓或阻止线粒体结构的异常改变,改善或维持其正常功能的执行,起到延缓衰老的作用,具体的机制还有待进一步的研究。
基金Project(50802034) supported by the National Natural Science Foundation of ChinaProject(11A093) supported by the Key Project Foundation by the Education Department of Hunan Province,China
文摘TiO2-coated activated carbon surface （TAs） composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow （AY） was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate.
文摘Orthogonal-test-design method has been used to determine the optimal formula by phase behavior and interfacial tension studies, respectively. The effect of each component of two alkaline/surfactant/polymer flooding systems on interfacial tension is discussed, in which a low-price natural mixed carboxylate (SDC) is used as the major surfactant. The results indicate that the optimal composition is SDC (0.5%), alkaline NaHCO3/Na2CO3 with mass ratio of 1 (1.0%), and hydrolyzed polyacrylamide(0.1%). In the coreflood experiment, their oil recovery is increased by about 25.2% and 26.8% original oil in place, respectively.
基金National Natural Science Foundation of China (Grant No.20671008/20971008)
文摘Vanadium compounds show potential in diabetes and cancer treatment, although the toxicity remains a great concern. Previous studies have shown that vanadium-induced oxidative stress affecting mitochondrial function is intensively responsible for the toxicity. In this work, we investigated the effects of the vanadium compounds sodium metavanadate （NaVO3） and vanadyl acetylacetonate （VO（acac）2） on mitochondrial ROS generation and respiratory complex activities. The experimental results showed that vanadium compounds affected the ROS generation and complex activities in different patterns depending on the chemical species. NaVO3 inhibited mitochondrial complexes Ⅰ and Ⅱ activities and stimulated ROS generation at low concentration range; while VO（acac）2 promoted complex Ⅱ activity but resulted in electron leakage from the complex Ⅰ-involved pathway. The present results provide new evidence for understanding the toxicity of antidiabetic vanadium compounds.
