目的研究芍药苷-6-氧-苯磺酸酯(CP-25)通过抑制GRK2活性对骨关节炎(osteoarthritis,OA)小鼠膝关节软骨的保护作用。方法内侧半月板失稳(destabilization of the medial meniscus,DMM)手术诱导构建小鼠骨关节炎模型,实验分为假手术组、...目的研究芍药苷-6-氧-苯磺酸酯(CP-25)通过抑制GRK2活性对骨关节炎(osteoarthritis,OA)小鼠膝关节软骨的保护作用。方法内侧半月板失稳(destabilization of the medial meniscus,DMM)手术诱导构建小鼠骨关节炎模型,实验分为假手术组、模型组、CP-25给药组和帕罗西汀给药组。术后开始灌胃给药。给药12周处死动物,Micro-CT成像观察膝关节软骨退变、骨重塑异常等情况,番红固绿染色观察小鼠关节组织病理,免疫组化、免疫荧光检测软骨组织相关分子表达水平的影响。Western blot检测CP-25用药后软骨细胞的膜蛋白及总蛋白表达水平。结果模型小鼠关节软骨严重退变。CP-25可显著降低关节软骨骨赘数量及软骨下板厚度,促进软骨基质再生,减少软骨基质降解蛋白表达,对膝关节软骨有明显的保护作用。免疫组化和免疫荧光结果显示,CP-25治疗可显著降低膝关节组织中GRK2、ADAMTS5、MMP13的表达,并且升高膝关节组织中ColⅡ、Aggrecan表达。体外实验结果表明,CP-25给药可以显著降低GRK2的膜蛋白及总蛋白表达水平,升高EP4膜蛋白水平,降低MMP13水平。结论CP-25给药可显著促进OA小鼠关节软骨基质再生,减少软骨基质降解,对OA具有治疗作用,其机制与抑制GRK2介导的软骨基质代谢有关。展开更多
Polyoxymethylene dimethyl ethers are recognized as the prospective diesel additive to decrease the pollutant emission from the light-duty vehicles,which can be polymerize form the monomer of dimethoxymethane(DMM).The ...Polyoxymethylene dimethyl ethers are recognized as the prospective diesel additive to decrease the pollutant emission from the light-duty vehicles,which can be polymerize form the monomer of dimethoxymethane(DMM).The industrial synthesis of DMM is mainly involved two-step process:methanol is oxidized to form the formaldehyde in fixed bed reactor and then reacted with the generated formaldehyde through acetalization in continuous stirred-tank reactor.Due to huge energy consumption,this typical synthesis route of DMM needs to be upgraded and more green routes should be determined.In this review,four state-of-the-art one-step direct synthetic routes,including two upgrading routes(methanol direct oxidation and direct dehydrogenation)and two green routes(methanol diethyl ether direct oxidation and carbon oxides direct hydrogenation),have been summarized and compared.Combination with the reaction mechanism and catalytic performance on the different catalysts,the challenges and opportu nities for every synthetic route are proposed.The relationships between catalyst structu re and property in different synthesis strategy are also investigated and then the suggestions of the design of catalyst are given about future research directions that efforts should be made in.Hopefully,this review can bridge the gap between newly developed catalysts and synthesis technology to realize their commercial applications in the near future.展开更多
The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40（40%）/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modifi...The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40（40%）/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modification of H3PW12O40（40%）/SiO2 gave the most promising result of 20% dimethyl ether conversion and 34.8% dimethoxymethane selectivity. Dimethoxymethane could be synthe- sized via methoxy groups decomposed from dimethyl ether through the synergistic effect between the acid sites and the redox sites of Cs modified H3PW12O40（40%）/SiO2.展开更多
Experimental investigation was conducted to convert dimethyl ether (DME) in the presence of steam using dielectric barrier discharge (DBD) at atmospheric pressure and 373 K. The flow rate of DME was 20 ml/min. The int...Experimental investigation was conducted to convert dimethyl ether (DME) in the presence of steam using dielectric barrier discharge (DBD) at atmospheric pressure and 373 K. The flow rate of DME was 20 ml/min. The introduction of steam resulted in an increase in the DME conversion and the selectivity of oxygenates. Plasma steam-enhanced dimethyl ether (DME) conversion led to a direct synthesis of DMMT and DMET, with a high selectivity of 5.78% and 17.99%, respectively. The addition of steam promoted the formation of 'plasma aerosol' that was favored for the formation of liquid oxygenates. The reaction pathway of plasma DME conversion was proposed.展开更多
文摘目的研究芍药苷-6-氧-苯磺酸酯(CP-25)通过抑制GRK2活性对骨关节炎(osteoarthritis,OA)小鼠膝关节软骨的保护作用。方法内侧半月板失稳(destabilization of the medial meniscus,DMM)手术诱导构建小鼠骨关节炎模型,实验分为假手术组、模型组、CP-25给药组和帕罗西汀给药组。术后开始灌胃给药。给药12周处死动物,Micro-CT成像观察膝关节软骨退变、骨重塑异常等情况,番红固绿染色观察小鼠关节组织病理,免疫组化、免疫荧光检测软骨组织相关分子表达水平的影响。Western blot检测CP-25用药后软骨细胞的膜蛋白及总蛋白表达水平。结果模型小鼠关节软骨严重退变。CP-25可显著降低关节软骨骨赘数量及软骨下板厚度,促进软骨基质再生,减少软骨基质降解蛋白表达,对膝关节软骨有明显的保护作用。免疫组化和免疫荧光结果显示,CP-25治疗可显著降低膝关节组织中GRK2、ADAMTS5、MMP13的表达,并且升高膝关节组织中ColⅡ、Aggrecan表达。体外实验结果表明,CP-25给药可以显著降低GRK2的膜蛋白及总蛋白表达水平,升高EP4膜蛋白水平,降低MMP13水平。结论CP-25给药可显著促进OA小鼠关节软骨基质再生,减少软骨基质降解,对OA具有治疗作用,其机制与抑制GRK2介导的软骨基质代谢有关。
文摘Polyoxymethylene dimethyl ethers are recognized as the prospective diesel additive to decrease the pollutant emission from the light-duty vehicles,which can be polymerize form the monomer of dimethoxymethane(DMM).The industrial synthesis of DMM is mainly involved two-step process:methanol is oxidized to form the formaldehyde in fixed bed reactor and then reacted with the generated formaldehyde through acetalization in continuous stirred-tank reactor.Due to huge energy consumption,this typical synthesis route of DMM needs to be upgraded and more green routes should be determined.In this review,four state-of-the-art one-step direct synthetic routes,including two upgrading routes(methanol direct oxidation and direct dehydrogenation)and two green routes(methanol diethyl ether direct oxidation and carbon oxides direct hydrogenation),have been summarized and compared.Combination with the reaction mechanism and catalytic performance on the different catalysts,the challenges and opportu nities for every synthetic route are proposed.The relationships between catalyst structu re and property in different synthesis strategy are also investigated and then the suggestions of the design of catalyst are given about future research directions that efforts should be made in.Hopefully,this review can bridge the gap between newly developed catalysts and synthesis technology to realize their commercial applications in the near future.
基金Foundation items:the National Natural Science Foundation of China(No.20373085)the Natural Science Foundation of Shanxi Province(No.20051023)
文摘The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40（40%）/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modification of H3PW12O40（40%）/SiO2 gave the most promising result of 20% dimethyl ether conversion and 34.8% dimethoxymethane selectivity. Dimethoxymethane could be synthe- sized via methoxy groups decomposed from dimethyl ether through the synergistic effect between the acid sites and the redox sites of Cs modified H3PW12O40（40%）/SiO2.
基金The project supported by the National Natural Science Foundation of China (No. 20376060)
文摘Experimental investigation was conducted to convert dimethyl ether (DME) in the presence of steam using dielectric barrier discharge (DBD) at atmospheric pressure and 373 K. The flow rate of DME was 20 ml/min. The introduction of steam resulted in an increase in the DME conversion and the selectivity of oxygenates. Plasma steam-enhanced dimethyl ether (DME) conversion led to a direct synthesis of DMMT and DMET, with a high selectivity of 5.78% and 17.99%, respectively. The addition of steam promoted the formation of 'plasma aerosol' that was favored for the formation of liquid oxygenates. The reaction pathway of plasma DME conversion was proposed.
