Clinical use of small-diameter vascular grafts remains a challenging issue in neovessel regeneration in view of thrombosis and intimal hyperplasia.Developing a vascular graft with structure and function similar to tho...Clinical use of small-diameter vascular grafts remains a challenging issue in neovessel regeneration in view of thrombosis and intimal hyperplasia.Developing a vascular graft with structure and function similar to those of the native vessels necessitates a major direction of vascular tissue regeneration.Thus,this study sought to design and fabricate a range of tri-phasic scaffolds(0,2,and 5 wt%gastrodin-polyurethane(PU))with spatiotemporally defined structure and gastrodin-release for regulating the highly coordinated processes in growth of the intima and media.While the small pores of inner layer guided infiltration of human umbilical vein endothelial cells(HUVECs),the bigger pores of medial layer could offer smooth muscle cell(SMC)-friendly habitat,and external fibers conferred adequate mechanical properties.Correspondingly,spatial distribution and differential regulation of key proteins in HUVECs and SMCs were mediated by hierarchical release of gastrodin,of which rapid release in inner layer elicited enhanced HUVEC proliferation and migration against those of the SMC via activated endothelial nitric oxide synthase(eNOS)and heat shock protein 70(HSP70)signal.Of note,superior anti-coagulation was reflected in 2 wt%gastrodin-PU ex vivo extracorporeal blood circulation experiment.After in vivo implantation for 12 weeks,there was no formation of obvious thrombosis and intimal hyperplasia in 2 wt%gastrodin-PU.The scaffold maintained high patency and improved vascular remodeling,including the formation of thin endothelialization in lumen and dense extracellular matrix deposition in medial layer.Taken together,the results demonstrate the positive function of hierarchical releasing system that responded to tri-phasic structure,which not only suppressed intimal thickening but also tightly controlled tissue regeneration.展开更多
In this paper,a reduced globus pallidus internal(GPI)-corticothalamic(GCT)model is developed,and a tri-phase delay stimulation(TPDS)with sequentially applying three pulses on the GPI representing the inputs from the s...In this paper,a reduced globus pallidus internal(GPI)-corticothalamic(GCT)model is developed,and a tri-phase delay stimulation(TPDS)with sequentially applying three pulses on the GPI representing the inputs from the striatal D_(1)neurons,subthalamic nucleus(STN),and globus pallidus external(GPE),respectively,is proposed.The GPI is evidenced to control absence seizures characterized by 2 Hz–4 Hz spike and wave discharge(SWD).Hence,based on the basal ganglia-thalamocortical(BGCT)model,we firstly explore the triple effects of D_(1)-GPI,GPE-GPI,and STN-GPI pathways on seizure patterns.Then,using the GCT model,we apply the TPDS on the GPI to potentially investigate the alternative and improved approach if these pathways to the GPI are blocked.The results show that the striatum D_(1),GPE,and STN can indeed jointly and significantly affect seizure patterns.In particular,the TPDS can effectively reproduce the seizure pattern if the D_(1)-GPI,GPE-GPI,and STN-GPI pathways are cut off.In addition,the seizure abatement can be obtained by well tuning the TPDS stimulation parameters.This implies that the TPDS can play the surrogate role similar to the modulation of basal ganglia,which hopefully can be helpful for the development of the brain-computer interface in the clinical application of epilepsy.展开更多
Carbon monoxide(CO)stands as one of the most valuable and economically viable products in the electrochemical reduction of CO_(2).In this study,we introduced high-surface-area porous carbon and anion-exchange ionomer ...Carbon monoxide(CO)stands as one of the most valuable and economically viable products in the electrochemical reduction of CO_(2).In this study,we introduced high-surface-area porous carbon and anion-exchange ionomer to silver nanoparticles,rapidly constructing a tri-phase interface that enhances CO_(2)transport and proton conduction.The ionomer-encapsulated tri-phase interface further improves reaction selectivity by increasing HCO_(3)^(-)concentration.Flow cell tests revealed that the 80%Ag/C catalyst doubles the partial current density of CO as compared to commercial Ag nanoparticles.To integrate the synthesized 80%Ag/C into industrial-scale membrane electrode assembly(MEA)electrolyzers(10 cm×10 cm),we developed a comprehensive evaluation system incorporating CO selectivity,cell voltage,and actual gas conversion ratio(λ_(act))with only one piece of MEA.This approach allowed systematic evaluation of current density and gas flow rate effects,followed by operational parameter optimization to 300 mA·cm^(-2)and 1000 standard cubic centimeters per minute(sccm).Under optimal conditions,the 80%Ag/C catalyst demonstrated stable operation for over 60 h with a cell voltage of 3 V.The observed CO Faradaic efficiency decay rate suggests a projected operational lifetime exceeding 500 h.This work not only presents an efficient modification strategy to enhance the CO_(2)reduction performance of silver-based catalysts,but also establishes a design-of-experiment(DOE)methodology for industrial-scale testing conditions optimization,thereby facilitating the advancement of CO_(2)reduction reaction(CO_(2)RR)toward practical industrial applications.展开更多
基金funded by National Natural Science Foundation of China(grant no.82260088,81960251,82260366)Yunnan Provincial Innovative Research Team in Basic and Clinical Study of Coronary Heart Disease of Yunnan Revitalization Talent Support Program(202305AS350030)+2 种基金Yunnan Science and Technology Program(202401AY070001-030,202201AT070136,202301AY070001-032,202001AY070001-014)Bai Xiaochun expert workstation(YSZJGZZ-2020040)Major Program of Kunming Science and Technology Innovation Center(2019-1-N-25318000003568).
文摘Clinical use of small-diameter vascular grafts remains a challenging issue in neovessel regeneration in view of thrombosis and intimal hyperplasia.Developing a vascular graft with structure and function similar to those of the native vessels necessitates a major direction of vascular tissue regeneration.Thus,this study sought to design and fabricate a range of tri-phasic scaffolds(0,2,and 5 wt%gastrodin-polyurethane(PU))with spatiotemporally defined structure and gastrodin-release for regulating the highly coordinated processes in growth of the intima and media.While the small pores of inner layer guided infiltration of human umbilical vein endothelial cells(HUVECs),the bigger pores of medial layer could offer smooth muscle cell(SMC)-friendly habitat,and external fibers conferred adequate mechanical properties.Correspondingly,spatial distribution and differential regulation of key proteins in HUVECs and SMCs were mediated by hierarchical release of gastrodin,of which rapid release in inner layer elicited enhanced HUVEC proliferation and migration against those of the SMC via activated endothelial nitric oxide synthase(eNOS)and heat shock protein 70(HSP70)signal.Of note,superior anti-coagulation was reflected in 2 wt%gastrodin-PU ex vivo extracorporeal blood circulation experiment.After in vivo implantation for 12 weeks,there was no formation of obvious thrombosis and intimal hyperplasia in 2 wt%gastrodin-PU.The scaffold maintained high patency and improved vascular remodeling,including the formation of thin endothelialization in lumen and dense extracellular matrix deposition in medial layer.Taken together,the results demonstrate the positive function of hierarchical releasing system that responded to tri-phasic structure,which not only suppressed intimal thickening but also tightly controlled tissue regeneration.
基金supported by the National Natural Science Foundation of China(Nos.11932003,12072021,and 11672074)。
文摘In this paper,a reduced globus pallidus internal(GPI)-corticothalamic(GCT)model is developed,and a tri-phase delay stimulation(TPDS)with sequentially applying three pulses on the GPI representing the inputs from the striatal D_(1)neurons,subthalamic nucleus(STN),and globus pallidus external(GPE),respectively,is proposed.The GPI is evidenced to control absence seizures characterized by 2 Hz–4 Hz spike and wave discharge(SWD).Hence,based on the basal ganglia-thalamocortical(BGCT)model,we firstly explore the triple effects of D_(1)-GPI,GPE-GPI,and STN-GPI pathways on seizure patterns.Then,using the GCT model,we apply the TPDS on the GPI to potentially investigate the alternative and improved approach if these pathways to the GPI are blocked.The results show that the striatum D_(1),GPE,and STN can indeed jointly and significantly affect seizure patterns.In particular,the TPDS can effectively reproduce the seizure pattern if the D_(1)-GPI,GPE-GPI,and STN-GPI pathways are cut off.In addition,the seizure abatement can be obtained by well tuning the TPDS stimulation parameters.This implies that the TPDS can play the surrogate role similar to the modulation of basal ganglia,which hopefully can be helpful for the development of the brain-computer interface in the clinical application of epilepsy.
基金supported by the National Natural Science Foundation of China(No.22175127).
文摘Carbon monoxide(CO)stands as one of the most valuable and economically viable products in the electrochemical reduction of CO_(2).In this study,we introduced high-surface-area porous carbon and anion-exchange ionomer to silver nanoparticles,rapidly constructing a tri-phase interface that enhances CO_(2)transport and proton conduction.The ionomer-encapsulated tri-phase interface further improves reaction selectivity by increasing HCO_(3)^(-)concentration.Flow cell tests revealed that the 80%Ag/C catalyst doubles the partial current density of CO as compared to commercial Ag nanoparticles.To integrate the synthesized 80%Ag/C into industrial-scale membrane electrode assembly(MEA)electrolyzers(10 cm×10 cm),we developed a comprehensive evaluation system incorporating CO selectivity,cell voltage,and actual gas conversion ratio(λ_(act))with only one piece of MEA.This approach allowed systematic evaluation of current density and gas flow rate effects,followed by operational parameter optimization to 300 mA·cm^(-2)and 1000 standard cubic centimeters per minute(sccm).Under optimal conditions,the 80%Ag/C catalyst demonstrated stable operation for over 60 h with a cell voltage of 3 V.The observed CO Faradaic efficiency decay rate suggests a projected operational lifetime exceeding 500 h.This work not only presents an efficient modification strategy to enhance the CO_(2)reduction performance of silver-based catalysts,but also establishes a design-of-experiment(DOE)methodology for industrial-scale testing conditions optimization,thereby facilitating the advancement of CO_(2)reduction reaction(CO_(2)RR)toward practical industrial applications.
