Using dispersion corrected density functional theory,we systematically examined the pressure effect on crystal structure,cell volume,and band gap of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB)to understand its extraord...Using dispersion corrected density functional theory,we systematically examined the pressure effect on crystal structure,cell volume,and band gap of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB)to understand its extraordinary chemical stability.Analysis of the Mulliken population and the electron density of states implied a possible charge transfer in TATB with increasing pressure.Raman and infrared spectra of TATB under hydrostatic pressure up to 30 GPa were simulated.The observed strong coupling between NH_2 groups and NO_(2) groups with increasing pressure,which is considered to have a tendency of energy transfer with these vibrational modes,was analyzed.The pressure-induced frequency shift of selected vibrational modes indicated minor changes of molecular conformation mainly by the rotation of NH_(2) groups.Compression behavior and spectroscopic property studies are expected to shed light on the physical and chemical properties of TATB on an atomistic scale.展开更多
目的探讨藏药莪达夏(OFB)对低氧性肺动脉高压(HPH)的干预作用及机制。方法选取130~150 g SPF级雄性SD大鼠60只,按照随机数字表法将其分为空白组、造模组、红景天组、低剂量组、中剂量组、高剂量组,每组10只。空白组大鼠饲养于青海大学SP...目的探讨藏药莪达夏(OFB)对低氧性肺动脉高压(HPH)的干预作用及机制。方法选取130~150 g SPF级雄性SD大鼠60只,按照随机数字表法将其分为空白组、造模组、红景天组、低剂量组、中剂量组、高剂量组,每组10只。空白组大鼠饲养于青海大学SPF级实验动物房,其余5组大鼠饲养于青海大学低压氧舱构建HPH模型;红景天组灌胃红景天醇提物200 mg/(kg·d),低、中、高剂量组分别灌胃OFB醇提物100、200、400 mg/(kg·d),空白组及造模组灌胃生理盐水,持续4周。比较各组大鼠右心室收缩压(RVSP)及右心肥厚指数(RVHI);评估各组大鼠肺动脉重塑程度;Western blot法及RT-qPCR检测各组大鼠葡萄糖-6-磷酸脱氢酶(G6PD)蛋白和mRNA表达;免疫组织化学染色法观察大鼠肺组织G6PD含量及分布;观察各组大鼠血清G6PD水平及肺组织NADP+/NADPH、总谷胱甘肽/氧化型谷胱甘肽(T-GSH/GSSG)、NADPH氧化酶(NOX)变化。结果造模组RVSP、RVHI高于空白组(P<0.05);低、中、高剂量组RVSP、RVHI低于造模组(P<0.05);中剂量组RVSP高于低剂量组(P<0.05);高剂量组RVSP低于中剂量组,RVHI高于中剂量组(P<0.05)。造模组血管壁面积占总血管面积的百分比(WA%)、血管壁厚度占血管外径的百分率(WT%)高于空白组(P<0.05);低、中、高剂量组WA%低于造模组(P<0.05),中剂量组WT%低于造模组(P<0.05);中剂量组WA%、WT%低于低剂量组(P<0.05)。造模组肺泡周围小血管G6PD阳性面积占比低于空白组(P<0.05);低、中、高剂量组肺泡周围小血管G6PD阳性面积占比低于造模组(P<0.05);高剂量组肺泡周围小血管G6PD阳性面积占比高于低剂量组(P<0.05)。造模组G6PD蛋白和mRNA表达低于空白组(P<0.05);低、中、高G6PD蛋白和mRNA表达低于造模组(P<0.05)。低剂量组肺组织NOX活力低于造模组(P<0.05);中剂量组血清G6PD及肺组织T-GSH/GSSG水平低于造模组(P<0.05);中剂量组血清G6PD水平低于低剂量组(P<0.05);高剂量组肺组织NADP+/NADPH、T-GSH/GSSG水平及NOX活力低于造模组(P<0.05)。结论400 mg/kg浓度OFB醇提物干预HPH效果最佳,其作用机制可能与下调G6PD减少磷酸戊糖途径下游信号传导有关。展开更多
基金Project supported by the Science Challenge Project of China(Grant No.TZ2016001)the National Natural Science Foundation of China(Grant Nos.11674046and 11372053)+2 种基金the Fundamental Research Funds for the Central Universities of China(Grant No.DUT17GF203)the Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,China(Grant No.KFJJ16-01M)the Supercomputing Center of Dalian University of Technology,China
文摘Using dispersion corrected density functional theory,we systematically examined the pressure effect on crystal structure,cell volume,and band gap of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB)to understand its extraordinary chemical stability.Analysis of the Mulliken population and the electron density of states implied a possible charge transfer in TATB with increasing pressure.Raman and infrared spectra of TATB under hydrostatic pressure up to 30 GPa were simulated.The observed strong coupling between NH_2 groups and NO_(2) groups with increasing pressure,which is considered to have a tendency of energy transfer with these vibrational modes,was analyzed.The pressure-induced frequency shift of selected vibrational modes indicated minor changes of molecular conformation mainly by the rotation of NH_(2) groups.Compression behavior and spectroscopic property studies are expected to shed light on the physical and chemical properties of TATB on an atomistic scale.
