目的探讨间歇性增加脑部逆灌压对深低温停循环脑保护的作用。方法 15头山羊随机分为深低温停循环组（A组,N=5）、深低温低压逆灌组（L组,N=5）和深低温间歇性高压逆灌组（H组,N=5）。三组动物均经历深低温（15-18℃）停循环2 h,期间A组...目的探讨间歇性增加脑部逆灌压对深低温停循环脑保护的作用。方法 15头山羊随机分为深低温停循环组（A组,N=5）、深低温低压逆灌组（L组,N=5）和深低温间歇性高压逆灌组（H组,N=5）。三组动物均经历深低温（15-18℃）停循环2 h,期间A组未行脑部逆行灌注,L组和H组经上腔静脉逆行灌注,L组逆灌压控制在20-25 mm Hg,H组基础逆灌压为20-25 mm Hg,每隔10 min用40-45 mm Hg的逆灌压灌注5 min,随后恢复至基础逆灌压。分别在体外循环前,深低温停循环前,复温开始,体外循环结束时记录平均动脉压、脑脊液压力和静脉血气值。用眼底镜观察羊的视网膜动静脉充盈情况。留取脑脊液标本,检测S-100含量。结果三组转流过程中平均动脉压、脑脊液压力、颈静脉血氧饱和度没有显著差异。三组颈静脉血乳酸值含量总体差异显著,H组低于L组和A组（P〈0.05）。配对t检验显示A组和L组体外循环结束后S-100含量明显高于体外循环前水平（P〈0.05）,但是H组没有显著变化。A组眼底视网膜血管没有血流,L组视网膜血管不充盈,H组在高流量灌注时视网膜血管充盈。结论间歇性增加脑逆灌压能够增加深低温停循环期间脑组织灌注,减少无氧代谢,对脑组织有保护作用。展开更多
Background Our previous study showed the 150 mg/mL fetal cardiac supernatant （FCS） could induce differentiation of BMSCs into cardiomyocye-like cells without cardiomyocyte touch,but differentiation efficiency is not...Background Our previous study showed the 150 mg/mL fetal cardiac supernatant （FCS） could induce differentiation of BMSCs into cardiomyocye-like cells without cardiomyocyte touch,but differentiation efficiency is not high enough.Inhibition of glycogen synthase kinase-3 enhanced the proliferation and survives of stem cells.We tested if 6-bromoindirubin-3-oxime （BIO,glycogen synthase kinase-3 inhibitor） enhances the effects of FCS on differentiation of BMSCs and explore the growth factors in FCS.Methods BMSCs were isolated from the femur and tibia of four-week-old male Sprague-Dawley rats and co-cultured with FCS （150 mg/mL） that was made from fetal hearts from nineteen-day pregnant Wistar rats.BIO with different concentration （0,1,10,and 100 nM） was introduced in culture dishes.Transforming growth factor beta 1 （TGF-β1）,bone morphogenetic protein 2 （BMP-2） and Akt in cardiac supernatant and culture medium were assayed with ELISA methods.Results After co-culturing with FCS,beating myotubes were observed in 25.9 % BMSCs dishes after 1 to 2 weeks＇ culture.The levels of TGF-β1 and BMP-2 in FCS concentrations were no more than that in young and adult cardiac supernatant.All BIO groups significantly enhanced the effects of FCS on differentiation of BMSCs into the cardiomyocyte-like cells （1 nM,83 %;10 nM,73 %;100 nM,100 %）.Akt levels were higher in BMSCs cultural medium with FCS.Conclusions FCS could induce the differentiation of BMSCs into the cardiomyocyte-like cells.TGF-β1 and BMP-2 might not play a role in the differentiation of BMSCs induced by FCS.BIO enhanced the effects of FCS on the differentiation of BMSCs into cardiomyocyte-like cells,which might involve the Akt pathway.展开更多
Background Currently used heart valve prostheses are associated with anticoagulation complications or limited durability. The advancement of stem cell study and tissue-engineered heart valve research may offer a relat...Background Currently used heart valve prostheses are associated with anticoagulation complications or limited durability. The advancement of stem cell study and tissue-engineered heart valve research may offer a relatively ideal solution to these problems. Methods Bone marrow was aspirated from sternum of lamb goats to isolate BMCs. Cells were identified by flow cytometry and its capacity of differentiation. Cellular viability was assessed with Rhdomine 123 staining. 1 × 10^7cells were seeded on a patch of PGA sheet. After two-day in vitro culture, autologous cell/ scaffold sheets were used to replace the right posterior pulmonary valve leaflets under cardiopulmonary bypass. The leaflets were explanted at 2 days, 2, 6, 8 and 10 weeks after implantation. The samples were examined macroscopically, histologically, immunohistochemically, and by Scanning Electron Microscope （SEM）. Two goats were implanted with acellular sheets and established as a control group. Results BMCs exhibited fibroblastoid morphology with good viability. Flow cytometry showed negative CD14 and CD45 expression. In vitro cultured BMCs demonstrated the potential to differentiate into adipocytes. The explanted leaflets resembled the characteristics of native extracellular matrix was leaflets macroscopicaIly in the cellular group. Histology showed synthesized and cells were distributed in the single-layered leaflets.Immunohistochemistry revealed positive staining for yon Willebrand factor, α-SMA, vimentin. A confluent cell surface was formed on the explanted TEHLs. No calcium deposited on the leaflets. In control group, the acellular scaffolds were completely degraded, without leaflet remained at 8 weeks. Conclusions It is possible to create tissue-engineered heart valves in vivo using autologous bone marrow-derived cells.展开更多
文摘目的探讨间歇性增加脑部逆灌压对深低温停循环脑保护的作用。方法 15头山羊随机分为深低温停循环组（A组,N=5）、深低温低压逆灌组（L组,N=5）和深低温间歇性高压逆灌组（H组,N=5）。三组动物均经历深低温（15-18℃）停循环2 h,期间A组未行脑部逆行灌注,L组和H组经上腔静脉逆行灌注,L组逆灌压控制在20-25 mm Hg,H组基础逆灌压为20-25 mm Hg,每隔10 min用40-45 mm Hg的逆灌压灌注5 min,随后恢复至基础逆灌压。分别在体外循环前,深低温停循环前,复温开始,体外循环结束时记录平均动脉压、脑脊液压力和静脉血气值。用眼底镜观察羊的视网膜动静脉充盈情况。留取脑脊液标本,检测S-100含量。结果三组转流过程中平均动脉压、脑脊液压力、颈静脉血氧饱和度没有显著差异。三组颈静脉血乳酸值含量总体差异显著,H组低于L组和A组（P〈0.05）。配对t检验显示A组和L组体外循环结束后S-100含量明显高于体外循环前水平（P〈0.05）,但是H组没有显著变化。A组眼底视网膜血管没有血流,L组视网膜血管不充盈,H组在高流量灌注时视网膜血管充盈。结论间歇性增加脑逆灌压能够增加深低温停循环期间脑组织灌注,减少无氧代谢,对脑组织有保护作用。
文摘Background Our previous study showed the 150 mg/mL fetal cardiac supernatant （FCS） could induce differentiation of BMSCs into cardiomyocye-like cells without cardiomyocyte touch,but differentiation efficiency is not high enough.Inhibition of glycogen synthase kinase-3 enhanced the proliferation and survives of stem cells.We tested if 6-bromoindirubin-3-oxime （BIO,glycogen synthase kinase-3 inhibitor） enhances the effects of FCS on differentiation of BMSCs and explore the growth factors in FCS.Methods BMSCs were isolated from the femur and tibia of four-week-old male Sprague-Dawley rats and co-cultured with FCS （150 mg/mL） that was made from fetal hearts from nineteen-day pregnant Wistar rats.BIO with different concentration （0,1,10,and 100 nM） was introduced in culture dishes.Transforming growth factor beta 1 （TGF-β1）,bone morphogenetic protein 2 （BMP-2） and Akt in cardiac supernatant and culture medium were assayed with ELISA methods.Results After co-culturing with FCS,beating myotubes were observed in 25.9 % BMSCs dishes after 1 to 2 weeks＇ culture.The levels of TGF-β1 and BMP-2 in FCS concentrations were no more than that in young and adult cardiac supernatant.All BIO groups significantly enhanced the effects of FCS on differentiation of BMSCs into the cardiomyocyte-like cells （1 nM,83 %;10 nM,73 %;100 nM,100 %）.Akt levels were higher in BMSCs cultural medium with FCS.Conclusions FCS could induce the differentiation of BMSCs into the cardiomyocyte-like cells.TGF-β1 and BMP-2 might not play a role in the differentiation of BMSCs induced by FCS.BIO enhanced the effects of FCS on the differentiation of BMSCs into cardiomyocyte-like cells,which might involve the Akt pathway.
基金supported by the grant from Guangdong Nature Science Foundation(7001117)
文摘Background Currently used heart valve prostheses are associated with anticoagulation complications or limited durability. The advancement of stem cell study and tissue-engineered heart valve research may offer a relatively ideal solution to these problems. Methods Bone marrow was aspirated from sternum of lamb goats to isolate BMCs. Cells were identified by flow cytometry and its capacity of differentiation. Cellular viability was assessed with Rhdomine 123 staining. 1 × 10^7cells were seeded on a patch of PGA sheet. After two-day in vitro culture, autologous cell/ scaffold sheets were used to replace the right posterior pulmonary valve leaflets under cardiopulmonary bypass. The leaflets were explanted at 2 days, 2, 6, 8 and 10 weeks after implantation. The samples were examined macroscopically, histologically, immunohistochemically, and by Scanning Electron Microscope （SEM）. Two goats were implanted with acellular sheets and established as a control group. Results BMCs exhibited fibroblastoid morphology with good viability. Flow cytometry showed negative CD14 and CD45 expression. In vitro cultured BMCs demonstrated the potential to differentiate into adipocytes. The explanted leaflets resembled the characteristics of native extracellular matrix was leaflets macroscopicaIly in the cellular group. Histology showed synthesized and cells were distributed in the single-layered leaflets.Immunohistochemistry revealed positive staining for yon Willebrand factor, α-SMA, vimentin. A confluent cell surface was formed on the explanted TEHLs. No calcium deposited on the leaflets. In control group, the acellular scaffolds were completely degraded, without leaflet remained at 8 weeks. Conclusions It is possible to create tissue-engineered heart valves in vivo using autologous bone marrow-derived cells.
