The photo-Fenton reaction is a key source of the highly reactive hydroxyl radical（HOU） that is produced by the reaction of simultaneous photo-induced generation of Fe^（2＋）-dissolved organic matter（DOM） with H_2...The photo-Fenton reaction is a key source of the highly reactive hydroxyl radical（HOU） that is produced by the reaction of simultaneous photo-induced generation of Fe^（2＋）-dissolved organic matter（DOM） with H_2O_2 in sunlit surface waters as well as in the treatment of organic pollutants in the advanced oxidation processes（AOPs）.Concentrations of both H_2O_2 and Fe^（2＋）-DOM were dependent on time and total solar intensity flux,and their levels were highest in the diurnal samples collected at noon compared with the samples collected during the period before sunrise and after sunset.H_2O_2 and Fe^（2＋）-DOM concentrations during monthly readings were also found higher in comparison with the diurnal samples,shortly before sunrise or after sunset.A π-electron bonding system is formed between Fe and the functional groups in DOM（Fe-DOM）,through electron donation from the functional groups of DOM to an empty d-orbital of Fe.The π-electron is loosely bound and is highly susceptible to a rapid excitation upon light exposure that will provide better understanding of the formation of aqueous electrons,superoxide radical anions,H_2O_2 and finally,photo-Fenton reactions,too.Our results imply that simultaneous generation of H_2O_2 and Fe^（2＋）-DOM upon sunlight exposure during the daytime is most likely to be the key photo-Fenton reaction pathway,taking place in surface waters.展开更多
The development of an excellent,bioabsorbable hemostatic material for deep wound remains a challenge.In this work,a biodegradable cotton-like biomimetic fibrous mat of poly(L-lactic acid)(PLLA)was made by melt spinnin...The development of an excellent,bioabsorbable hemostatic material for deep wound remains a challenge.In this work,a biodegradable cotton-like biomimetic fibrous mat of poly(L-lactic acid)(PLLA)was made by melt spinning.Subsequently,SD composite was prepared by cross-linking sodium alginate(SA)with dopamine(DA).It was immobilized on the fibre surface,which inspired by mussel byssus.Finally,Fe^(3+)was loaded onto the 0.5SD/PLLA composite by chelation with the carboxyl of alginate and phenolic hydroxy of dopamine.The haemostasis experiment found that the hemostatic time 47 s in vitro.However,the bleeding volume was 0.097 g and hemostatic time was 23 s when 20Fe^(3+)-0.5SD/PLLA was applied in the haemostasis of the rat liver.As a result of its robust hydrophilicity and bouffant cotton-like structure,it could absorb a large water from blood,which could concentrate the component of blood and reduce the clotting time.Furthermore,the addition of Fe^(3+)in the 0.5SD/PLLA had a significant effect on improve hemostatic property.It also displayed excellent antibacterial property for Escherichia coli and Staphylococcus aureus.Notably,it possesses superior hemocompatibility,cytocompatibility and histocompatibility.Hence,20Fe^(3+)-0.5SD/PLLA has high potential application in haemostasis for clinical settings due to its outstanding properties.展开更多
目的:研究Fe^(3+)和Cys对CHO细胞表达免疫球蛋白G(IgG)电荷异构体比例的影响。方法:在补料分批培养外泌表达IgG的CHO细胞株中,以不同的策略单独或联合添加不同浓度的Fe^(3+)或Cys;培养14 d后离心得上清液,通过生化分析仪测定上清液中Ig...目的:研究Fe^(3+)和Cys对CHO细胞表达免疫球蛋白G(IgG)电荷异构体比例的影响。方法:在补料分批培养外泌表达IgG的CHO细胞株中,以不同的策略单独或联合添加不同浓度的Fe^(3+)或Cys;培养14 d后离心得上清液,通过生化分析仪测定上清液中IgG的含量,利用Protein A MagBeads亲和纯化该抗体,通过糖基化修饰、阳离子亲和层析(CEX)、非还原十二烷基硫酸钠毛细管电泳(nrCE-SDS)、硼酸亲和层析(BAC)及疏水相互作用色谱(HIC)进行鉴定。结果:Fe^(3+)的添加可提高IgG酸性异构体比例,并且Cys可增强Fe^(3+)的提升效果,仅添加Cys对酸性异构体的比例没有影响;电荷异构体表征表明酸性异构体含量提高主要源于唾液酸修饰、片段、Fc段氨基酸位点氧化修饰以及糖化水平的增加。结论:Fe^(3+)与Cys通过提高唾液酸修饰、片段的丰度、糖化水平以及某些氨基酸位点的氧化,导致IgG酸性异构体比例显著增加。展开更多
基金the Japan Society for the Promotion of Science for the financial support through a Grant-in-Aid for Scientific Research (B) (No.18310010)partly supported by the Key Construction Program of the National "985" Project,Tianjin University,China
文摘The photo-Fenton reaction is a key source of the highly reactive hydroxyl radical（HOU） that is produced by the reaction of simultaneous photo-induced generation of Fe^（2＋）-dissolved organic matter（DOM） with H_2O_2 in sunlit surface waters as well as in the treatment of organic pollutants in the advanced oxidation processes（AOPs）.Concentrations of both H_2O_2 and Fe^（2＋）-DOM were dependent on time and total solar intensity flux,and their levels were highest in the diurnal samples collected at noon compared with the samples collected during the period before sunrise and after sunset.H_2O_2 and Fe^（2＋）-DOM concentrations during monthly readings were also found higher in comparison with the diurnal samples,shortly before sunrise or after sunset.A π-electron bonding system is formed between Fe and the functional groups in DOM（Fe-DOM）,through electron donation from the functional groups of DOM to an empty d-orbital of Fe.The π-electron is loosely bound and is highly susceptible to a rapid excitation upon light exposure that will provide better understanding of the formation of aqueous electrons,superoxide radical anions,H_2O_2 and finally,photo-Fenton reactions,too.Our results imply that simultaneous generation of H_2O_2 and Fe^（2＋）-DOM upon sunlight exposure during the daytime is most likely to be the key photo-Fenton reaction pathway,taking place in surface waters.
基金supported by the Jilin Scientific and Technological Development Program(20200404110YY)National Natural Science Foundation of China(51673186).
文摘The development of an excellent,bioabsorbable hemostatic material for deep wound remains a challenge.In this work,a biodegradable cotton-like biomimetic fibrous mat of poly(L-lactic acid)(PLLA)was made by melt spinning.Subsequently,SD composite was prepared by cross-linking sodium alginate(SA)with dopamine(DA).It was immobilized on the fibre surface,which inspired by mussel byssus.Finally,Fe^(3+)was loaded onto the 0.5SD/PLLA composite by chelation with the carboxyl of alginate and phenolic hydroxy of dopamine.The haemostasis experiment found that the hemostatic time 47 s in vitro.However,the bleeding volume was 0.097 g and hemostatic time was 23 s when 20Fe^(3+)-0.5SD/PLLA was applied in the haemostasis of the rat liver.As a result of its robust hydrophilicity and bouffant cotton-like structure,it could absorb a large water from blood,which could concentrate the component of blood and reduce the clotting time.Furthermore,the addition of Fe^(3+)in the 0.5SD/PLLA had a significant effect on improve hemostatic property.It also displayed excellent antibacterial property for Escherichia coli and Staphylococcus aureus.Notably,it possesses superior hemocompatibility,cytocompatibility and histocompatibility.Hence,20Fe^(3+)-0.5SD/PLLA has high potential application in haemostasis for clinical settings due to its outstanding properties.
文摘目的:研究Fe^(3+)和Cys对CHO细胞表达免疫球蛋白G(IgG)电荷异构体比例的影响。方法:在补料分批培养外泌表达IgG的CHO细胞株中,以不同的策略单独或联合添加不同浓度的Fe^(3+)或Cys;培养14 d后离心得上清液,通过生化分析仪测定上清液中IgG的含量,利用Protein A MagBeads亲和纯化该抗体,通过糖基化修饰、阳离子亲和层析(CEX)、非还原十二烷基硫酸钠毛细管电泳(nrCE-SDS)、硼酸亲和层析(BAC)及疏水相互作用色谱(HIC)进行鉴定。结果:Fe^(3+)的添加可提高IgG酸性异构体比例,并且Cys可增强Fe^(3+)的提升效果,仅添加Cys对酸性异构体的比例没有影响;电荷异构体表征表明酸性异构体含量提高主要源于唾液酸修饰、片段、Fc段氨基酸位点氧化修饰以及糖化水平的增加。结论:Fe^(3+)与Cys通过提高唾液酸修饰、片段的丰度、糖化水平以及某些氨基酸位点的氧化,导致IgG酸性异构体比例显著增加。
