Hemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons,which is life-threatening in severe cases.Because microhemorrhage is difficult to visually monitor and pre-treat in vi...Hemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons,which is life-threatening in severe cases.Because microhemorrhage is difficult to visually monitor and pre-treat in vivo,it is necessary to establish in vitro prediction methods to study the hemostasis mechanism in different physiological environments.In this study,a microfluidic bleeding model was developed to investigate the effect of blood flow shear on microvascular hemostasis.The results indicated that the regulation of blood shear rate on platelet aggregation affected the growth and morphology of hemostatic thrombus,and finally regulated the process of hemostasis.This in vitro model is significant to studies on hemostatic mechanisms,a reliable prediction of microhemorrhages,and an adjustment of the treatment scheme.展开更多
Hydrophilic polymer coatings can improve the surface characteristics of artificial implants.However,because they are used in vivo,they inevitably come into contact with biomolecules that affect their interfacial tribo...Hydrophilic polymer coatings can improve the surface characteristics of artificial implants.However,because they are used in vivo,they inevitably come into contact with biomolecules that affect their interfacial tribological properties.In this paper,the friction behaviors of poly(vinylphosphonic acid)(PVPA)-modified Ti6Al4V and polytetrafluorethylene balls were analyzed using albumin,globulin,aggrecan,and hyaluronic acid as lubricants.The interaction properties and dynamic adsorption characteristics of the biomolecules and PVPA molecules were explored by a quartz crystal microbalance to identify the cause of the friction difference.It was found that protein molecules disturbed the superlubricity of the PVPA-phosphate-buffered saline system because of the formation of a stable adsorption film,which replaced the interfacial characteristics of the PVPA coating.Polysaccharides,with their excellent hydration properties and polymer structure,had an unstable dynamic interaction or zero adsorption with PVPA molecules,and hardly changed the superlubricity of the PVPA and phosphate-buffered-saline system.The influence mechanism of the specific friction of proteins and polysaccharides was analyzed.Interactions were observed among different biomolecules.Polysaccharides can potentially reduce protein adsorption.The result of the synergistic regulation of the friction coefficient for PVPA-modified Ti6Al4V is approximately 0.017.The results of this study will provide a theoretical basis for the use of polymer coatings in vivo.展开更多
基金This study was supported by the National Natural Science Foundation of China(No.51875304)the National Key R&D Program of China(No.2018YFE0114900).
文摘Hemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons,which is life-threatening in severe cases.Because microhemorrhage is difficult to visually monitor and pre-treat in vivo,it is necessary to establish in vitro prediction methods to study the hemostasis mechanism in different physiological environments.In this study,a microfluidic bleeding model was developed to investigate the effect of blood flow shear on microvascular hemostasis.The results indicated that the regulation of blood shear rate on platelet aggregation affected the growth and morphology of hemostatic thrombus,and finally regulated the process of hemostasis.This in vitro model is significant to studies on hemostatic mechanisms,a reliable prediction of microhemorrhages,and an adjustment of the treatment scheme.
基金This work was supported by the National Natural Science Foundation of China(51705010,51875303)the Beijing Natural Science Foundation(3192003)+2 种基金the General Project of Science and Technology Plan from Beijing Educational Committee(KM201810005013)the Tribology Science Fund of State Key Laboratory of Tribology(STLEKF16A02,SKLTKF19B08)the training program of Rixin talent and outstanding talent from Beijing University of Technology.
文摘Hydrophilic polymer coatings can improve the surface characteristics of artificial implants.However,because they are used in vivo,they inevitably come into contact with biomolecules that affect their interfacial tribological properties.In this paper,the friction behaviors of poly(vinylphosphonic acid)(PVPA)-modified Ti6Al4V and polytetrafluorethylene balls were analyzed using albumin,globulin,aggrecan,and hyaluronic acid as lubricants.The interaction properties and dynamic adsorption characteristics of the biomolecules and PVPA molecules were explored by a quartz crystal microbalance to identify the cause of the friction difference.It was found that protein molecules disturbed the superlubricity of the PVPA-phosphate-buffered saline system because of the formation of a stable adsorption film,which replaced the interfacial characteristics of the PVPA coating.Polysaccharides,with their excellent hydration properties and polymer structure,had an unstable dynamic interaction or zero adsorption with PVPA molecules,and hardly changed the superlubricity of the PVPA and phosphate-buffered-saline system.The influence mechanism of the specific friction of proteins and polysaccharides was analyzed.Interactions were observed among different biomolecules.Polysaccharides can potentially reduce protein adsorption.The result of the synergistic regulation of the friction coefficient for PVPA-modified Ti6Al4V is approximately 0.017.The results of this study will provide a theoretical basis for the use of polymer coatings in vivo.
