Objective To investigate the effect and mechanism of epigallocatechin-3-gallate (EGCG) on restenosis of the vein graft. Methods Totally 90 Sprague-Dawley rats were randomly divided a the control group, a vein graft group and an EGCG+vein graft group. At week 1, 2 and 4, the intimal and tunica thickness of the venous graft wall was evaluated by hematoxylin-eosin staining, and the expression of Ki-67 was assessed by immunohistochemistry analysis, and then the expression of hairy and enhancer of split-1 (HES1) was measured by Western blot assay. Results At week 2, the intimal thickness (46.76±4.89 μmvs. 8.93±0.82 μm, 46.76±4.89 μmvs. 34.24±3.57 μm), tunica thickness (47.28±4.37vs. 16.33±1.52 μm, 47.28±4.37vs. 36.27±3.29 μm), positive cell rate of Ki-67 (21.59%±2.29%vs. 1.12%±0.22%, 21.59%±2.29%vs. 15.38%±1.30%), expression of HES1 respectively increased in the experimental group than those in the control group and the EGCG+vein graft group (P<0.05, respectively). At week 4, the intimal thickness (66.38±6.23 μmvs. 8.29±0.79 μm, 66.38±6.23 μmvs. 48.39±4.23 μm), tunica thickness (63.27±6.18 μmvs. 15.29±1.49 μm, 63.27±6.18 μmvs. 44.63±4.49 μm), positive cell rate of Ki-67 (33.19%±3.03%vs. 1.09%±0.19%, 33.19%±3.03%vs. 24.37%±2.73%), expression of HES1 increased in the experimental group than those in the control group and EGCG+vein graft group (P<0.05, respectively). Conclusion EGCG may inhibite restenosis of vein graft by inhibiting Notch signal pathway.
ObjectiveTo investigate the effect of simvastatin and mechanical pretreatment on intimal hyperplasia of venous graft and its mechanism.MethodsTwelve New Zealand rabbits were selected and randomly divided into 4 groups: a blank control group, a simvastatin topical treatment group, a mechanical precondition group and a combined group (n=3 in each group). Ultrasound was used to evaluate the changes of graft wall and blood flow velocity in the graft, and pathological section was used to evaluate the intimal hyperplasia. Human umbilical cord endodermal cells were cultured in vitro. A simvastatin group and a solvent control group were set to detect YAP phosphorylation, downstream target gene expression and cell proliferation.ResultsVascular ultrasound showed that except the simvastatin topical treatment group, the flow velocity in vein grafts in the other three groups significantly increased 21 days after surgery compared with 7 days after surgery (P<0.01). Pathological sections showed that the thickness of new intima in the simvastatin topical treatment group, mechanical precondition group, combined group and blank control group were 45.56±4.11 μm, 201.28±16.71 μm, 143.57±7.82 μm, 249.45±13.33 μm, respectively, and there were statistical differences compared with the blank control group (P<0.05). In vitro results showed that compared with the solvent control group, cell death was observed in high concentration simvastatin (5 mmol/L) group, cell proliferation was inhibited in low concentration simvastatin (2.5 mmol/L) group (P<0.05), the expression of YAP protein in the simvastatin group was unchanged, but the expression of phosphorylated YAP protein significantly increased (P<0.05), and the expression of downstream target gene ccn1 was down-regulated (P<0.001).ConclusionIntravascular local application of simvastatin and mechanical preconditioning alone or in combination can inhibit intimal hyperplasia of venous graft. High concentration of simvastatin has cytotoxicity, while low concentration of simvastatin has inhibitory effect on cell proliferation. Simvastatin can inhibit the formation of new intima by inhibiting the entry of YAP into the nucleus and reducing the transcription of cell proliferation-related target gene ccn1.
ObjectiveTo assess the effects of Radix Salviae Miltiorrhizae (RSM) on patency and proliferation lesion of autologous vein to artery grafts in the earlymiddle stage.MethodsAutologous jugular vein was grafted into abdominal artery in the rats. The rats were divided into two groups: RSM group and control group. The rats in RSM group were fed with RSM ［24 g/(kg·d )］,which began 1 day before operation and continued until harvesting. Vein grafts were harvested at 1,3 days, 1, 2, 4 and 8 weeks after surgery for examining the patency, thickness of intimamedia and expression of proliferating cell nuclear antigen (PCNA). ResultsNo significant differences existed in patency of vein grafts between the two groups (Pgt;0.05). The intimamedia thickness of the vein grafts in RSM group decreased 1/3 compared with control group at 2, 4 and 8 weeks (P＜0.01). The PCNA positive cells in RSM group reduced significantly as compared to the control group (P＜0.01). ConclusionRSM can inhibit proliferation lesion of vein grafts but has no influence on patency of vein grafts in the earlymiddle stage.
In order to prevent tendon adhesion following operation, autogenous great saphenous vein graft was used to reconstruct the tendon sheath. The operation was performed under microsurgical technique. This method was used to repair 23 tendons and 17 tendon sheaths. The early functional exercises were carried out after operation. Follow up from 10 months to 4 years, the prognosis was good except in 3 fingers, in which, the wounds were infected resulting the necrosis of the grafted veins and exposure of the repaired tendons. The details of the operation were introduced. It was emphasized that non-traumatic handling of the tissues was essential in preventing tendon from adhesion.
In order to solve the defect of blood vessel in tissue transplantation and complicated palmar amputation, bridge by "Y" type vein had been used from Jan. 1990 to Jul. 1996. Twenty-three cases were treated. In this series, there were 16 males and 7 females, with ages ranged from 10 to 42 years old. Six cases were the defect of lower legs anterior skin and tibia, 3 cases were the femur fracture with injury of femoral artery and tissue’s defect, 2 cases were defect of five fingers, 12 cases were complicated palmar amputation. RESULT: 15 cases with tissue transplantation and 12 cases with limb replantation were all survival without infection or necrosis. After the following-up for 3 years (ranged from 1 to 5 years), the function of injured limbs were satisfactory, 19 patients had resumed their original work. So, to bridge by "Y" type vein is a good method for repairing the defect of blood vessels in tissue transplantation and complicated palmar amputation, but skilled microsurgery technique is required.