Non-alcoholic fatty liver disease(NAFLD)is a common liver disease in Western populations.Nonalcoholic steatohepatitis(NASH)is a more debilitating form of NAFLD characterized by hepatocellular injury and inflammation,w...Non-alcoholic fatty liver disease(NAFLD)is a common liver disease in Western populations.Nonalcoholic steatohepatitis(NASH)is a more debilitating form of NAFLD characterized by hepatocellular injury and inflammation,which significantly increase the risk of end-stage liver and cardiovascular diseases.Unfortunately,there are no available drug therapies for NASH.Bile acids are physiological detergent molecules that are synthesized from cholesterol exclusively in the hepatocytes.Bile acids circulate between the liver and intestine,where they are required for cholesterol solubilization in the bile and dietary fat emulsification in the gut.Bile acids also act as signaling molecules that regulate metabolic homeostasis and inflammatory processes.Many of these effects are mediated by the bile acid-activated nuclear receptor farnesoid X receptor(FXR)and the G protein-coupled receptor TGR5.Nutrient signaling regulates hepatic bile acid synthesis and circulating plasma bile acid concentrations,which in turn control metabolic homeostasis.The FXR agonist obeticholic acid has had beneficial effects on NASH in recent clinical trials.Preclinical studies have suggested that the TGR5 agonist and the FXR/TGR5 dual agonist are also potential therapies for metabolic liver diseases.Extensive studies in the past few decades have significantly improved our understanding of the metabolic regulatory function of bile acids,which has provided the molecular basis for developing promising bile acid-based therapeutic agents for NASH treatment.展开更多
The Sr2 CeO4:Ln3+(Ln=Eu,Dy)fine phosphor particles were prepared by a facile wet chemical approach,in which the consecutive hydrothermal-combustion reaction was performed.The doping of Ln3+into Sr2 CeO4 has little inf...The Sr2 CeO4:Ln3+(Ln=Eu,Dy)fine phosphor particles were prepared by a facile wet chemical approach,in which the consecutive hydrothermal-combustion reaction was performed.The doping of Ln3+into Sr2 CeO4 has little influence on the structure of host,and the as-prepared samples display wellcrystallized spherical or elliptical shape with an average particle size at about 100-200 nm.For Eu3+ions-doped Sr2 CeO4,with the increase of Eu3+-doping concentration,the blue light emission band with the maximum at 468 nm originating from a Ce4+→O2-charge transfer of the host decreases obviously and the characteristic red light emission of Eu3+(5 D0→7 F2 transition at 618 nm)is enhanced gradually.Simultaneously,the fluorescent lifetime of the broadband emission of Sr2 CeO4 decreases with the doping of Eu3+,indicating an efficient energy transfer from the host to the doping Eu3+ions.The ene rgy transfer efficiency from the host to Eu3+was investigated in detail,and the emitting color of Sr2 CeO4:Eu3+can be easily tuned from blue to red by varying the doping concentration of Eu3+ions.Moreover,the luminescence of Dy3+-doped Sr2 CeO4 was also studied.Similar energy transfer pheno menon can be observed,and the incorporation of Dy3+into Sr2 CeO4 host leads to the characteristic emission of 4 F9/2→6 H15/2(488 nm,blue light)and 4 F9/2→6 H13/2(574 nm,yellow light)of Dy3+.The Sr2 CeO4:Ln3+fine particles with tunable luminescence are quite beneficial for its potential applications in the optoelectronic fields.展开更多
Molecular structures of adsorbed waters at metal surfaces are essential to understanding the widespread processes ranging from ice nucleation,to water involved catalytic surface reactions,to many phenomena of biologic...Molecular structures of adsorbed waters at metal surfaces are essential to understanding the widespread processes ranging from ice nucleation,to water involved catalytic surface reactions,to many phenomena of biological and astrochemical importance.Instead of providing a comprehensive literature survey,we focus in this review on detailed structural information,such as water orientations and occupation sites,of intact waters at low temperatures and ultrahigh vacuum conditions investigated by various surface techniques.Despite progresses made in direct imaging the surface waters at high resolutions,as exemplified in a close-packed（e.g.Pd（111）） and an open metal surfaces（e.g.Cu（110）） supported waters,structural mysteries remain at diverse metal surfaces.We highlight experimental challenges and discuss structural mysteries in elucidating surface water structures at molecular levels.展开更多
基金This work was supported in part by an American Diabetes Association Junior Faculty Award 7-12-JF-35National Institutes of Health grants 1R01DK102487-01 and P20GM103549&P30GM118247.
文摘Non-alcoholic fatty liver disease(NAFLD)is a common liver disease in Western populations.Nonalcoholic steatohepatitis(NASH)is a more debilitating form of NAFLD characterized by hepatocellular injury and inflammation,which significantly increase the risk of end-stage liver and cardiovascular diseases.Unfortunately,there are no available drug therapies for NASH.Bile acids are physiological detergent molecules that are synthesized from cholesterol exclusively in the hepatocytes.Bile acids circulate between the liver and intestine,where they are required for cholesterol solubilization in the bile and dietary fat emulsification in the gut.Bile acids also act as signaling molecules that regulate metabolic homeostasis and inflammatory processes.Many of these effects are mediated by the bile acid-activated nuclear receptor farnesoid X receptor(FXR)and the G protein-coupled receptor TGR5.Nutrient signaling regulates hepatic bile acid synthesis and circulating plasma bile acid concentrations,which in turn control metabolic homeostasis.The FXR agonist obeticholic acid has had beneficial effects on NASH in recent clinical trials.Preclinical studies have suggested that the TGR5 agonist and the FXR/TGR5 dual agonist are also potential therapies for metabolic liver diseases.Extensive studies in the past few decades have significantly improved our understanding of the metabolic regulatory function of bile acids,which has provided the molecular basis for developing promising bile acid-based therapeutic agents for NASH treatment.
基金Project supported by National Natural Science Foundation of China(51972097)This work was financially supported by the Science Foundation of Hebei Normal University,China(L2019K11).This work was also financially supported by the project WINLEDS—POCI-01-0145-FEDER-030351 and developed within the scope of the project CICECO-Aveiro Institute of Materials,FCT Ref.UID/CTM/50011/2019,financed by national funds through the FCT/MCTES.
文摘The Sr2 CeO4:Ln3+(Ln=Eu,Dy)fine phosphor particles were prepared by a facile wet chemical approach,in which the consecutive hydrothermal-combustion reaction was performed.The doping of Ln3+into Sr2 CeO4 has little influence on the structure of host,and the as-prepared samples display wellcrystallized spherical or elliptical shape with an average particle size at about 100-200 nm.For Eu3+ions-doped Sr2 CeO4,with the increase of Eu3+-doping concentration,the blue light emission band with the maximum at 468 nm originating from a Ce4+→O2-charge transfer of the host decreases obviously and the characteristic red light emission of Eu3+(5 D0→7 F2 transition at 618 nm)is enhanced gradually.Simultaneously,the fluorescent lifetime of the broadband emission of Sr2 CeO4 decreases with the doping of Eu3+,indicating an efficient energy transfer from the host to the doping Eu3+ions.The ene rgy transfer efficiency from the host to Eu3+was investigated in detail,and the emitting color of Sr2 CeO4:Eu3+can be easily tuned from blue to red by varying the doping concentration of Eu3+ions.Moreover,the luminescence of Dy3+-doped Sr2 CeO4 was also studied.Similar energy transfer pheno menon can be observed,and the incorporation of Dy3+into Sr2 CeO4 host leads to the characteristic emission of 4 F9/2→6 H15/2(488 nm,blue light)and 4 F9/2→6 H13/2(574 nm,yellow light)of Dy3+.The Sr2 CeO4:Ln3+fine particles with tunable luminescence are quite beneficial for its potential applications in the optoelectronic fields.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.YYYJ-0912)
文摘Molecular structures of adsorbed waters at metal surfaces are essential to understanding the widespread processes ranging from ice nucleation,to water involved catalytic surface reactions,to many phenomena of biological and astrochemical importance.Instead of providing a comprehensive literature survey,we focus in this review on detailed structural information,such as water orientations and occupation sites,of intact waters at low temperatures and ultrahigh vacuum conditions investigated by various surface techniques.Despite progresses made in direct imaging the surface waters at high resolutions,as exemplified in a close-packed（e.g.Pd（111）） and an open metal surfaces（e.g.Cu（110）） supported waters,structural mysteries remain at diverse metal surfaces.We highlight experimental challenges and discuss structural mysteries in elucidating surface water structures at molecular levels.
