长江三峡的演化问题一直是地学界争论的焦点和热点。近年来,不少学者通过锆石、石榴子石、角闪石等重矿物的同位素和微量元素组成来判断长江物源,取得了较好的成果,但将单颗粒铁质重矿物作为物源指示矿物并应用于三峡贯通方面研究较少...长江三峡的演化问题一直是地学界争论的焦点和热点。近年来,不少学者通过锆石、石榴子石、角闪石等重矿物的同位素和微量元素组成来判断长江物源,取得了较好的成果,但将单颗粒铁质重矿物作为物源指示矿物并应用于三峡贯通方面研究较少。因此作者运用电子探针、扫描电镜和能谱仪对湖北宜昌地区第四纪沉积物中的铁质重矿物进行化学特征和形貌分析,并与可能的物源区样品进行对比,来分析物源演化过程及判定三峡贯通时间。研究结果显示,宜昌地区第四纪沉积铁质重矿物的主要源岩为位于三峡以西的攀枝花钒钛磁铁矿、峨眉山玄武岩和位于三峡以东的黄陵花岗岩,在善溪窑组沉积结束以后,宜昌地区第四纪沉积物的物源发生了明显改变,出现来自三峡以西的物质,表明长江三峡此时发生了贯通。结合ESR测年数据和前人研究结果可知,长江三峡的贯通发生在0.75—0.73 Ma B.P.。展开更多
Objective:To interpret the pharmacology of quercetin in treatment of atherosclerosis(AS).Methods:Fourteen apolipoprotein E-deficient(ApoE^(-/-))mice were divided into 2 groups by a random number table:an AS model(ApoE...Objective:To interpret the pharmacology of quercetin in treatment of atherosclerosis(AS).Methods:Fourteen apolipoprotein E-deficient(ApoE^(-/-))mice were divided into 2 groups by a random number table:an AS model(ApoE^(-/-))group and a quercetin treatment group(7 in each).Seven age-matched C57 mice were used as controls(n=7).Quercetin[20 mg/(kg·d)]was administered to the quercetin group intragastrically for 8 weeks for pharmacodynamic evaluation.Besides morphological observation,the distribution of CD11b,F4/80,sirtuin 1(Sirt1)and P21 was assayed by immunohistochemistry and immunofluorescence to evaluate macrophage infiltration and tissue senescence.Ultra-performance liquid chromatography/tandem mass spectrometry(UPLC-MSC/MS)was performed to study the pharmacology of quercetin against AS.Then,simultaneous administration of an apelin receptor antagonist(ML221)with quercetin was conducted to verify the possible targets of quercetin.Key proteins in apelin signaling pathway,such as angiotensin domain type 1 receptor-associated proteins(APJ),AMP-activated protein kinase(AMPK),peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α),tissue plasminogen activator(TPA),uncoupling protein 1(UCP1)and angiotensinⅡreceptor 1(AT1R),were assayed by Western blot.Results:Quercetin administration decreased lipid deposition in arterial lumen and improved the morphology of ApoE^(-/-)aortas in vivo.Quercetin decreased the densities of CD11b,F4/80 and P21 in the aorta and increased the level of serum apelin and the densities of APJ and Sirt1 in the aorta in ApoE^(-/-)mice(all P<0.05).Plasma metabolite profiling identified 118 differential metabolites and showed that quercetin affected mainly glycerophospholipids and fatty acyls.Bioinformatics analysis suggested that the apelin signaling pathway was one of the main pathways.Quercetin treatment increased the protein expressions of APJ,AMPK,PGC-1α,TPA and UCP1,while decreased the AT1R level(all P<0.05).After the apelin pathway was blocked by ML221,the effect of quercetin was abated significantly,confirming that quercetin attenuated AS by modulating the apelin signaling pathway(all P<0.05).Conclusion:Quercetin alleviated AS lesions by up-regulation the apelin signaling pathway.展开更多
文摘长江三峡的演化问题一直是地学界争论的焦点和热点。近年来,不少学者通过锆石、石榴子石、角闪石等重矿物的同位素和微量元素组成来判断长江物源,取得了较好的成果,但将单颗粒铁质重矿物作为物源指示矿物并应用于三峡贯通方面研究较少。因此作者运用电子探针、扫描电镜和能谱仪对湖北宜昌地区第四纪沉积物中的铁质重矿物进行化学特征和形貌分析,并与可能的物源区样品进行对比,来分析物源演化过程及判定三峡贯通时间。研究结果显示,宜昌地区第四纪沉积铁质重矿物的主要源岩为位于三峡以西的攀枝花钒钛磁铁矿、峨眉山玄武岩和位于三峡以东的黄陵花岗岩,在善溪窑组沉积结束以后,宜昌地区第四纪沉积物的物源发生了明显改变,出现来自三峡以西的物质,表明长江三峡此时发生了贯通。结合ESR测年数据和前人研究结果可知,长江三峡的贯通发生在0.75—0.73 Ma B.P.。
基金Supported by Shandong Province'Taishan Scholar'Construction Project Funds (No.2018-35)。
文摘Objective:To interpret the pharmacology of quercetin in treatment of atherosclerosis(AS).Methods:Fourteen apolipoprotein E-deficient(ApoE^(-/-))mice were divided into 2 groups by a random number table:an AS model(ApoE^(-/-))group and a quercetin treatment group(7 in each).Seven age-matched C57 mice were used as controls(n=7).Quercetin[20 mg/(kg·d)]was administered to the quercetin group intragastrically for 8 weeks for pharmacodynamic evaluation.Besides morphological observation,the distribution of CD11b,F4/80,sirtuin 1(Sirt1)and P21 was assayed by immunohistochemistry and immunofluorescence to evaluate macrophage infiltration and tissue senescence.Ultra-performance liquid chromatography/tandem mass spectrometry(UPLC-MSC/MS)was performed to study the pharmacology of quercetin against AS.Then,simultaneous administration of an apelin receptor antagonist(ML221)with quercetin was conducted to verify the possible targets of quercetin.Key proteins in apelin signaling pathway,such as angiotensin domain type 1 receptor-associated proteins(APJ),AMP-activated protein kinase(AMPK),peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α),tissue plasminogen activator(TPA),uncoupling protein 1(UCP1)and angiotensinⅡreceptor 1(AT1R),were assayed by Western blot.Results:Quercetin administration decreased lipid deposition in arterial lumen and improved the morphology of ApoE^(-/-)aortas in vivo.Quercetin decreased the densities of CD11b,F4/80 and P21 in the aorta and increased the level of serum apelin and the densities of APJ and Sirt1 in the aorta in ApoE^(-/-)mice(all P<0.05).Plasma metabolite profiling identified 118 differential metabolites and showed that quercetin affected mainly glycerophospholipids and fatty acyls.Bioinformatics analysis suggested that the apelin signaling pathway was one of the main pathways.Quercetin treatment increased the protein expressions of APJ,AMPK,PGC-1α,TPA and UCP1,while decreased the AT1R level(all P<0.05).After the apelin pathway was blocked by ML221,the effect of quercetin was abated significantly,confirming that quercetin attenuated AS by modulating the apelin signaling pathway(all P<0.05).Conclusion:Quercetin alleviated AS lesions by up-regulation the apelin signaling pathway.
