目的采用微焦点断层扫描(Micro-CT)评价超声骨焊接技术应用过程中超声震荡产热作用下PDLLA材料对骨愈合性能的影响。方法选择SPF级雄性新西兰大白兔36只,随机分为超声骨焊接技术辅助PDLLA材料组(A组)、拧入技术辅助PDLLA材料组(B组)、...目的采用微焦点断层扫描(Micro-CT)评价超声骨焊接技术应用过程中超声震荡产热作用下PDLLA材料对骨愈合性能的影响。方法选择SPF级雄性新西兰大白兔36只,随机分为超声骨焊接技术辅助PDLLA材料组(A组)、拧入技术辅助PDLLA材料组(B组)、假手术组(C组)、空白对照组(D组),各9只。于术后4、8、12周取下颌骨标本,周围骨组织进行HE染色,观察各组植入钉周围情况。对术后4、8、12周的下颌骨大体标本拍摄Micro-CT图,使用VG Studio MAX软件进行三维重建,摆正数据样本,即颌骨颊侧造模处为轴向,动态分析植入钉体积、植入钉周围200μm环状区及骨缺损处的植入材料体积数、相对骨体积分数(BV/TV)、骨小梁厚度(Tb.Th)、骨小梁数(Tb.N)、骨小梁间隙(Tb.Sp)等骨愈合相关指标。结果HE染色结果显示,按3个时间可动态观察到A、B、C组骨缺损处骨性骨痂替代纤维性骨痂,形成类骨质,编织骨的过程符合正常骨损伤愈合的过程。Micro-CT结果显示,A、B组术后3个时间点的材料体积比较差异均无统计学意义(P>0.05);在3个时间点,4组植入钉周围200μm环状区中BV/TV、Tb.Th、Tb.N、Tb.Sp比较差异均无统计学意义(P>0.05);在骨缺损处,A、B、C组三个时间点BV/TV、Tb.Th、Tb.N、Tb.Sp比较差异无统计学意义(P>0.05);术后4周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.N、Tb.Sp差异有统计学意义(P<0.05);与C组比较,A、B组Tb.N差异有统计学意义(P<0.01)。术后8周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.N、Tb.Sp差异有统计学意义(P<0.05);术后12周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.Sp差异有统计学意义(P<0.05)。结论超声骨焊接技术其超声震荡产热作用下PDLLA材料对骨愈合性能无不良影响。展开更多
目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓...目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓度(CMC);采用溶剂蒸发法制备DPT-PM溶液,并将其冷冻干燥;分别采用动态光散射法(DLS)、透射电子显微镜(TEM)、差示扫描量热法(DSC)、高效液相色谱法(HPLC)等手段对胶束形态、粒径与分布、载药量、包封率等进行表征,并采用透析法考察DPT-PM体外释放,并对释放机制进行探讨。结果制备了去氧鬼臼毒素共聚物胶束,透射电镜下观察为近球形,平均粒径为22.0±8.9nm,载药量为20.67%,包封率为99.63%。结论 m PEG-PDLLA聚合物胶束可作为疏水性药物去氧鬼臼毒素的载体,具有较高的载药性能,能一定程度提高去氧鬼臼毒素在水中的溶解度。展开更多
Polyethylene glycol(PEG)was added at different concentrations to the blend of poly(L-lactic acid)(PLLA)and poly(D,L-lactic acid)(PDLLA)to tailor the properties.The differential scanning calorimetry(DSC)measurement sho...Polyethylene glycol(PEG)was added at different concentrations to the blend of poly(L-lactic acid)(PLLA)and poly(D,L-lactic acid)(PDLLA)to tailor the properties.The differential scanning calorimetry(DSC)measurement showed that all blends were miscible due to shifting a single glass transition temperature into a lower temperature for increasing PEG content.The DSC,FTIR,and XRD results implied the crystallinity enhancement for PEG content until 8 wt%,then decreased at 12 wt%PEG.The XRD result indicated the homo crystalline phase formation in all blends and no stereocomplex crystal.The in vitro degradation study indicated that PEG content is proportional to the degradation rate.The highest weight loss after 28 days was achieved at 12 wt%PEG.The FTIR analysis showed a structural evolution overview during hydrolytic degradation,viz.increasing and decreasing crystallinity during 14 days for the blend without and with PEG,respectively.In conclusion,the PEG addition increased crystallinity and degradation rate of the PLLA/PDLLA mixture,but PEG higher amounts led to a decrease in crystallinity,and the weight loss was intensified.This can be useful for tuning PLA-based biomaterials with the desired physicochemical properties and appropriate degradation rates for applications in drug delivery/tissue engineering.展开更多
文摘目的采用微焦点断层扫描(Micro-CT)评价超声骨焊接技术应用过程中超声震荡产热作用下PDLLA材料对骨愈合性能的影响。方法选择SPF级雄性新西兰大白兔36只,随机分为超声骨焊接技术辅助PDLLA材料组(A组)、拧入技术辅助PDLLA材料组(B组)、假手术组(C组)、空白对照组(D组),各9只。于术后4、8、12周取下颌骨标本,周围骨组织进行HE染色,观察各组植入钉周围情况。对术后4、8、12周的下颌骨大体标本拍摄Micro-CT图,使用VG Studio MAX软件进行三维重建,摆正数据样本,即颌骨颊侧造模处为轴向,动态分析植入钉体积、植入钉周围200μm环状区及骨缺损处的植入材料体积数、相对骨体积分数(BV/TV)、骨小梁厚度(Tb.Th)、骨小梁数(Tb.N)、骨小梁间隙(Tb.Sp)等骨愈合相关指标。结果HE染色结果显示,按3个时间可动态观察到A、B、C组骨缺损处骨性骨痂替代纤维性骨痂,形成类骨质,编织骨的过程符合正常骨损伤愈合的过程。Micro-CT结果显示,A、B组术后3个时间点的材料体积比较差异均无统计学意义(P>0.05);在3个时间点,4组植入钉周围200μm环状区中BV/TV、Tb.Th、Tb.N、Tb.Sp比较差异均无统计学意义(P>0.05);在骨缺损处,A、B、C组三个时间点BV/TV、Tb.Th、Tb.N、Tb.Sp比较差异无统计学意义(P>0.05);术后4周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.N、Tb.Sp差异有统计学意义(P<0.05);与C组比较,A、B组Tb.N差异有统计学意义(P<0.01)。术后8周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.N、Tb.Sp差异有统计学意义(P<0.05);术后12周,与D组比较,A、B、C组BV/TV、Tb.Th、Tb.Sp差异有统计学意义(P<0.05)。结论超声骨焊接技术其超声震荡产热作用下PDLLA材料对骨愈合性能无不良影响。
文摘目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓度(CMC);采用溶剂蒸发法制备DPT-PM溶液,并将其冷冻干燥;分别采用动态光散射法(DLS)、透射电子显微镜(TEM)、差示扫描量热法(DSC)、高效液相色谱法(HPLC)等手段对胶束形态、粒径与分布、载药量、包封率等进行表征,并采用透析法考察DPT-PM体外释放,并对释放机制进行探讨。结果制备了去氧鬼臼毒素共聚物胶束,透射电镜下观察为近球形,平均粒径为22.0±8.9nm,载药量为20.67%,包封率为99.63%。结论 m PEG-PDLLA聚合物胶束可作为疏水性药物去氧鬼臼毒素的载体,具有较高的载药性能,能一定程度提高去氧鬼臼毒素在水中的溶解度。
基金Funding Statement:This work was supported by Universitas Indonesia under Grant PUTI 2020(No.NKB-4325/UN2.RST/HKP.05.00/2020).
文摘Polyethylene glycol(PEG)was added at different concentrations to the blend of poly(L-lactic acid)(PLLA)and poly(D,L-lactic acid)(PDLLA)to tailor the properties.The differential scanning calorimetry(DSC)measurement showed that all blends were miscible due to shifting a single glass transition temperature into a lower temperature for increasing PEG content.The DSC,FTIR,and XRD results implied the crystallinity enhancement for PEG content until 8 wt%,then decreased at 12 wt%PEG.The XRD result indicated the homo crystalline phase formation in all blends and no stereocomplex crystal.The in vitro degradation study indicated that PEG content is proportional to the degradation rate.The highest weight loss after 28 days was achieved at 12 wt%PEG.The FTIR analysis showed a structural evolution overview during hydrolytic degradation,viz.increasing and decreasing crystallinity during 14 days for the blend without and with PEG,respectively.In conclusion,the PEG addition increased crystallinity and degradation rate of the PLLA/PDLLA mixture,but PEG higher amounts led to a decrease in crystallinity,and the weight loss was intensified.This can be useful for tuning PLA-based biomaterials with the desired physicochemical properties and appropriate degradation rates for applications in drug delivery/tissue engineering.
