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
Density functional theory （DFT） plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential （USPP） method, the crystal...Density functional theory （DFT） plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential （USPP） method, the crystal structures of α,β,γ, and 5-Bi2O3 were optimally calculated for the total density of states （TDOS） and the partial density of states （PDOS） of Bi, O atoms. The calculation for Ti（IV） doped Bi2O3 supercell was carried out. The effects of Ti（IV）-doping on the electron structures and light absorption properties of various Bi2O3 were analyzed. The results showed that Ti 3d orbital appeared in the forbidden band of Bi2O3 and hybridized with O 2p, Bi 6p orbitals. The narrowed band gap （Eg） and red-shift of light absorption edge are responsible for the enhanced photoeatalytic activity of Bi2O3. The Ⅱ-Bi2O3 and Ti-doped β-Bi2O3 were prepared by a hydrotherrnal synthesis method. The improvement of the photoeatalytic activity of Bi2O3 has also been verified by the characteristics of the UV-vis diffuse reflection spectrum and the experimental evaluation of the photocatalytic degradation of crystal violet in aqueous solution.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supported by the National High Technology Research and Development Program (863 program, 2006AA06Z323)National Key Technology R&D Program (2008BAC32B06-3) of Chinaspecial fund of State Key Laboratory of Water Environment Simulation (08ESPCT-Z)
文摘Density functional theory （DFT） plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential （USPP） method, the crystal structures of α,β,γ, and 5-Bi2O3 were optimally calculated for the total density of states （TDOS） and the partial density of states （PDOS） of Bi, O atoms. The calculation for Ti（IV） doped Bi2O3 supercell was carried out. The effects of Ti（IV）-doping on the electron structures and light absorption properties of various Bi2O3 were analyzed. The results showed that Ti 3d orbital appeared in the forbidden band of Bi2O3 and hybridized with O 2p, Bi 6p orbitals. The narrowed band gap （Eg） and red-shift of light absorption edge are responsible for the enhanced photoeatalytic activity of Bi2O3. The Ⅱ-Bi2O3 and Ti-doped β-Bi2O3 were prepared by a hydrotherrnal synthesis method. The improvement of the photoeatalytic activity of Bi2O3 has also been verified by the characteristics of the UV-vis diffuse reflection spectrum and the experimental evaluation of the photocatalytic degradation of crystal violet in aqueous solution.
