Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegra...Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegradable property of silicone stents and nickel-titanium memory alloy stents take the primary responsibility for drawbacks including stimulating local granulation tissue proliferation,displacement,and stent-related infections.Permanent tracheobronchial stent will be a persistent foreign object for a long time,causing excessive secretion of tracheal mucosa,ulceration and even perforation,which is particularly unsuitable for young children with persistent tracheal growth.In this study,the degradation and biocompatibility performance of three typical biodegradable metals were investigated as potential tracheobronchial stent materials.The results exhibited that these materials showed different degradation behaviors in the simulating respiratory fluid environment compared with SBF.Except for pure iron group,high purity magnesium and zinc showed favorable cell adhesion and proliferation in three culture methodologies(direct culture,indirect culture and extraction culture).The proper corrosion rate and good biocompatibility indicated that high purity magnesium and zinc may be good candidates as tracheobronchial stent materials.展开更多
A well designed coating for polyetheretherketone(PEEK)implants can provide enough support to overcome crucial medical challenges,which are insufficient osseointegration and high rate of infection.Herein,we utilize the...A well designed coating for polyetheretherketone(PEEK)implants can provide enough support to overcome crucial medical challenges,which are insufficient osseointegration and high rate of infection.Herein,we utilize the co-deposition of polydopamine(PDA)and copper-citrate nanoclusters to construct a p H-responsive coating on porous PEEK for synergistic bone regeneration,vascular formation and anti-infection.Specifically,this PDA coating released high dose of copper and citrate at lower p H value,which increased intracellular copper content,boosted production of reactive oxygen species and severe damage of protein,leading to killing of 93%planktonic bacterial and eradication of adherent bacteria.At p H of 7.4,the release of copper and citrate were in a slow and sustained behavior,synergistically enhanced vascular formation potential and osteodiffereration of Ad-MSC in vitro.After implanted in rabbit tibia for 6 and 12 weeks,the micro-CT evaluation and histological analysis consistently highlighted the ability of this PDA coating to increase new bone formation adjacent to coated PEEK implant and enhance bone-implant interfacial integration.These results were proven to be related to the synergistic effect that citrate facilitated a 2-fold influx of copper into cells,which not only enhanced the bacteria-killing ability but also encouraged bone regeneration of implants.This present work provides an effective method to control infections while promoting osseointegration simultaneously,which will show tremendous clinical application and can be a solution to current challenges facing orthopedics.展开更多
基金the Grant from Ministry of Science and Technology of China(2016YFB1101501)and researchfinancial support from the Beijing AKEC Medical Co.,Ltd.Medical Research Center of Peking University Third Hospital
基金supported by National Natural Science Foundation of China(No.31670974,No.31370954).
文摘Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegradable property of silicone stents and nickel-titanium memory alloy stents take the primary responsibility for drawbacks including stimulating local granulation tissue proliferation,displacement,and stent-related infections.Permanent tracheobronchial stent will be a persistent foreign object for a long time,causing excessive secretion of tracheal mucosa,ulceration and even perforation,which is particularly unsuitable for young children with persistent tracheal growth.In this study,the degradation and biocompatibility performance of three typical biodegradable metals were investigated as potential tracheobronchial stent materials.The results exhibited that these materials showed different degradation behaviors in the simulating respiratory fluid environment compared with SBF.Except for pure iron group,high purity magnesium and zinc showed favorable cell adhesion and proliferation in three culture methodologies(direct culture,indirect culture and extraction culture).The proper corrosion rate and good biocompatibility indicated that high purity magnesium and zinc may be good candidates as tracheobronchial stent materials.
基金financially supported by the National Key Research and Development Project(2018YFC1106600)National Natural Science Foundation of China(No.31670974,No.31370954,No.51901003)。
文摘A well designed coating for polyetheretherketone(PEEK)implants can provide enough support to overcome crucial medical challenges,which are insufficient osseointegration and high rate of infection.Herein,we utilize the co-deposition of polydopamine(PDA)and copper-citrate nanoclusters to construct a p H-responsive coating on porous PEEK for synergistic bone regeneration,vascular formation and anti-infection.Specifically,this PDA coating released high dose of copper and citrate at lower p H value,which increased intracellular copper content,boosted production of reactive oxygen species and severe damage of protein,leading to killing of 93%planktonic bacterial and eradication of adherent bacteria.At p H of 7.4,the release of copper and citrate were in a slow and sustained behavior,synergistically enhanced vascular formation potential and osteodiffereration of Ad-MSC in vitro.After implanted in rabbit tibia for 6 and 12 weeks,the micro-CT evaluation and histological analysis consistently highlighted the ability of this PDA coating to increase new bone formation adjacent to coated PEEK implant and enhance bone-implant interfacial integration.These results were proven to be related to the synergistic effect that citrate facilitated a 2-fold influx of copper into cells,which not only enhanced the bacteria-killing ability but also encouraged bone regeneration of implants.This present work provides an effective method to control infections while promoting osseointegration simultaneously,which will show tremendous clinical application and can be a solution to current challenges facing orthopedics.
