Objective To develop a new vascular xenograft and to compare the in vivo behavior of thrombogenicity and intimal hyperplasia in the heparin-treated and the non-heparin-treated decellularized xenografts.Methods Canine ...Objective To develop a new vascular xenograft and to compare the in vivo behavior of thrombogenicity and intimal hyperplasia in the heparin-treated and the non-heparin-treated decellularized xenografts.Methods Canine common carotid arteries were decellularized by enzymatic and detergent extraction procedures.Then a part of decellularized vascular grafts were covalently linked with heparin.Xenografts with(n=24)and without(n=24)heparin treatment were implanted in rabbits' left and right carotid artery respectively as bypass grafts.Graft patency were checked by Duplex ultrasonography at 3 and 6 months after implantation.Twelve rabbits were euthanized randomly at 3 and 6 months respectively and bilateral grafts were explanted.Histological examination and immunohistochemical staining were performed to observe the vascular remodeling.The efficiency of heparin release was demonstrated with toluidine blue staining.HE staining and micrograph analysis system were used for valuating the intima hyperplasia(IH)of bilateral grafts.Results During implantation,thrombosis rate was 4% in the heparin-treated xenografts and 25% in the non-heparin-treated xenografts after 3 weeks(P<0.05).After 6 months,it was 8% versus 58% respectively(P<0.01).Both xenografts of two groups harvested at the end of 3 or 6 months showed a satisfactory cellular reconstruction of either smooth muscle cells or endothelial cells.Intimal hyperplasia in the heparin-treated vascular was less than in the non-heparin treated xenografts.In addition,intimal hyperplasia was liable to appear close to the proximal and distal anastomotic stoma.Toluidine blue staining demonstrated that heparin was slowly released during 6 months.Conclusion This study provides a new strategy to develop a small-caliber vascular xenograft through enzymatic-detergent extraction and heparin treatment.Heparin treatment of the decellularized xenograft is helpful for improving bypass graft patency and reducing intimal hyperplasia.If there was no thrombus,bilateral bypass grafts will undergo a vessel remodeling procedure.Canine common carotid artery treated by detergent and enzymatic extraction and heparin treatment may be used as a new small-caliber vascular xenograft.展开更多
目的研究低分子肝素对大鼠高脂血症性胰腺炎胰腺微循环的作用机制。方法将72只健康SD大鼠随机分成假手术组、模型组和治疗组各24只,每组再随机分成四个亚组。先采用高脂饮食建立高脂血症模型,模型组和治疗组制作大鼠急性胰腺炎模型,制...目的研究低分子肝素对大鼠高脂血症性胰腺炎胰腺微循环的作用机制。方法将72只健康SD大鼠随机分成假手术组、模型组和治疗组各24只,每组再随机分成四个亚组。先采用高脂饮食建立高脂血症模型,模型组和治疗组制作大鼠急性胰腺炎模型,制模成功后治疗组分别于0、6、12、18 h开始使用低分子肝素皮下注射,各亚组均间隔6 h重复皮下注射一次,每亚组均干预4次;模型组和假手术组同时间点皮下注射等量生理盐水对照。结果大鼠胰腺血流速度模型组低于假手术组,治疗组高于模型组(P<0.05);胰腺组织病理学评分模型组高于假手术组,治疗组低于模型组(P<0.05);模型组各亚组胰腺血管内皮生长因子(VEGF)蛋白表达、VEGF m RNA表达水平均高于假手术组,而治疗组均低于模型组(P<0.05)。结论大鼠高脂血症性胰腺炎,VEGF与微循环障碍密切相关;低分子肝素可能通过下调胰腺组织VEGF水平来改善胰腺微循环障碍,减轻胰腺组织进一步损害,且早期干预价值更大。展开更多
文摘Objective To develop a new vascular xenograft and to compare the in vivo behavior of thrombogenicity and intimal hyperplasia in the heparin-treated and the non-heparin-treated decellularized xenografts.Methods Canine common carotid arteries were decellularized by enzymatic and detergent extraction procedures.Then a part of decellularized vascular grafts were covalently linked with heparin.Xenografts with(n=24)and without(n=24)heparin treatment were implanted in rabbits' left and right carotid artery respectively as bypass grafts.Graft patency were checked by Duplex ultrasonography at 3 and 6 months after implantation.Twelve rabbits were euthanized randomly at 3 and 6 months respectively and bilateral grafts were explanted.Histological examination and immunohistochemical staining were performed to observe the vascular remodeling.The efficiency of heparin release was demonstrated with toluidine blue staining.HE staining and micrograph analysis system were used for valuating the intima hyperplasia(IH)of bilateral grafts.Results During implantation,thrombosis rate was 4% in the heparin-treated xenografts and 25% in the non-heparin-treated xenografts after 3 weeks(P<0.05).After 6 months,it was 8% versus 58% respectively(P<0.01).Both xenografts of two groups harvested at the end of 3 or 6 months showed a satisfactory cellular reconstruction of either smooth muscle cells or endothelial cells.Intimal hyperplasia in the heparin-treated vascular was less than in the non-heparin treated xenografts.In addition,intimal hyperplasia was liable to appear close to the proximal and distal anastomotic stoma.Toluidine blue staining demonstrated that heparin was slowly released during 6 months.Conclusion This study provides a new strategy to develop a small-caliber vascular xenograft through enzymatic-detergent extraction and heparin treatment.Heparin treatment of the decellularized xenograft is helpful for improving bypass graft patency and reducing intimal hyperplasia.If there was no thrombus,bilateral bypass grafts will undergo a vessel remodeling procedure.Canine common carotid artery treated by detergent and enzymatic extraction and heparin treatment may be used as a new small-caliber vascular xenograft.
文摘目的研究低分子肝素对大鼠高脂血症性胰腺炎胰腺微循环的作用机制。方法将72只健康SD大鼠随机分成假手术组、模型组和治疗组各24只,每组再随机分成四个亚组。先采用高脂饮食建立高脂血症模型,模型组和治疗组制作大鼠急性胰腺炎模型,制模成功后治疗组分别于0、6、12、18 h开始使用低分子肝素皮下注射,各亚组均间隔6 h重复皮下注射一次,每亚组均干预4次;模型组和假手术组同时间点皮下注射等量生理盐水对照。结果大鼠胰腺血流速度模型组低于假手术组,治疗组高于模型组(P<0.05);胰腺组织病理学评分模型组高于假手术组,治疗组低于模型组(P<0.05);模型组各亚组胰腺血管内皮生长因子(VEGF)蛋白表达、VEGF m RNA表达水平均高于假手术组,而治疗组均低于模型组(P<0.05)。结论大鼠高脂血症性胰腺炎,VEGF与微循环障碍密切相关;低分子肝素可能通过下调胰腺组织VEGF水平来改善胰腺微循环障碍,减轻胰腺组织进一步损害,且早期干预价值更大。
