MICROCIRCULATION OF A VENOUS FLAP: AN EXPERIMENTAL STUDY WITH MICROSPHERES IN RABBITS

In recent years, it has been found that maintenance of venous circulation alone may support a small flap with no direct arterial inflow. The clinical application of a venous flap has potential in the field of microsurgery. The purpose of this study was to evaluate the haemodynamics within a pedicled venous flap in rabbits, compared with those of a composite graft. Pedicled venous flaps and composite grafts were raised from the abdominal walls of 30 adult New Zealand rabbits. Flap survival was measured and recorded and blood flow studies with microspheres were done for seven days. The viability of the pedicled venous flaps was much better than that of the composite grafts. At two weeks 24 of the venous flaps (80%) showed more than 75% surviving, but 29 (97%) of the composite grafts had less than 25% surviving. The results suggest that the blood flow through a patent vein maintained in a venous skin flap can provide enough nutrients for the flap to survive during the initial three days until neovascularisation. The venous flap receives more blood flow than a composite graft. We conclude that a venous flap depends on blood supply from the axial vein in addition to neovascularisation to maintain its survival.     

Effect of cyclosporine on oxidative phosphorylation and adenylate energy charge of regenerating rat liver

The effect of cyclosporin A (CyA) on regenerating liver was investigated in subtotal hepatectomized rats treated with CyA in terms of mitochondrial phosphorylative activity, hepatic energy charge, and serum bilirubin levels. In the CyA-treated hepatectomized group, the energy charge decreased from normal control value of 0.857 to 0.782 at 6 h after hepatectomy. The decreased energy charge, however, gradually increased and returned to 0.842 at 48 h after hepatectomy with no significant changes being observed between CyA-treated and untreated hepatectomized groups. Phosphorylation rate in the CyA-untreated group increased to 142% of the normal control at 24 h and then decreased to 114% at 48 h after hepatectomy. By contrast, phosphorylation rate in the CyA-treated group increased to 144% of the normal control at 24 h, but remained at the high value of 132% (P less than 0.01; compared to the CyA-untreated group) even at 48 h after hepatectomy. Serum total bilirubin levels in the CyA-treated group were significantly higher than those in the CyA-untreated group during all experimental periods. We conclude that CyA does not exert a direct detrimental effect on mitochondrial function and that, despite the marked hyperbilirubinemia induced by CyA, the mitochondrial phosphorylative activity increases adaptively to provide sufficient energy for enhanced ATP-utilizing reactions in an early process of liver regeneration.     

借助人工神经修复大鼠坐骨神经缺损的实验研究

目的：研究人工神经－壳聚糖复合胶大气层 管修复大鼠坐骨神经15mm缺损的可行性。方法：借助人工神经修复10只大鼠坐骨神经缺损15mm，神经缺损7只为对照组，术后2个月，4个月行免疫组化，Osmium染色、Bodian染色，运动终板的特异染色、WGA－HRP神经示踪及大体观察。结果：术后2个月再生神经修复了坐骨神经的缺损，实验动物未出现排斥反应及明显的炎症反应。结论：人工神经导管对缺损的坐骨神经修复具有良好的桥梁作用和促神经生长的作用。     

感觉性和运动性神经膜细胞的培养研究

目的对感觉性和运动性神经来源的神经膜细胞进行培养和鉴定,并通过神经生长因子(NGF)的表达间接地研究两种细胞的差别,探讨对神经特异性再生的影响。方法立体显微镜下对SD乳鼠后根神经和股神经运动支进行取材,经2.5g/L胰蛋白酶+0.3g/LIV型胶原酶联合消化,用高糖型DMEM/F12(含100g/LCS)对感觉神经源性和运动神经源性的神经膜细胞进行培养,并经抗S100荧光组织化学染色鉴定。双抗体夹心间接ELISA法测量两种神经膜细胞培养基中NGF的表达。结果培养的两种神经膜细胞经荧光染色证明均为神经膜细胞,光镜观察并手工计数显示两种细胞纯度均超过95%,未见形态学差异,但NGF的表达量和表达模式差异均有显著性意义(F=45.3681,P=0.000)。结论本实验方法可以获得高纯度的感觉性和运动性神经源性神经膜细胞,两者的生物学功能有差异。     

Spontaneous recovery of myocardial function after ligation of Ameroid-stenosed coronary artery

Objectives. We aimed to assess the spontaneous healing of myocardial function after occlusion of a chronically stenosed coronary vessel in a porcine model. Design. Ischemia and infarction was produced by Ameroid constrictor placement and a subsequent ligation of the left circumflex artery. Cardiac MRI and 18FDG-PET were performed one and five weeks later. Ki67 staining was used to identify proliferating cells. Results. Restoration of perfusion defect was detected by MRI (p=0.0065), reduced systolic function of the lateral segment spontaneously recovered (p=0.03). There was also a suggestive raise in impaired ejection fraction (p=0.06). Left ventricular early diastolic filling and peak filling rate were substantially improved (p=0.039 and p=0.0078). Scar size reduced (p=0.03). On the 18FDG-PET, deranged metabolism was alleviated (p=0.03). Cardiomyocytes with positive Ki-67 staining were located principally in the non-infarcted myocardium as compared to the infarction or border areas (p=0.037). Conclusions. We demonstrated spontaneous functional healing of ischemic and infarcted left ventricle, suggesting border zone perfusion recovery. Scar reduction was detected. Different pattern of myocyte proliferation between infarction and non-ischemic myocardium was seen.     

周围神经损伤后Schwann细胞与轴突再生关系的超微形态学研究

目的观察大鼠坐骨神经损伤后Schwann细胞和轴突再生关系的超微结构变化。方法切断大鼠双侧坐骨神经，在神经断端间留有3mm间隙构建冲经再生室。分为A组和B组，在A组左侧（A1）神经再生室内注入0．1ml生理盐水，右侧（A2）注入0．05ml丝裂霉素（40μg/ml）和0．05ml层粘连蛋白（10μg／ml）;在B组左侧（B1）神经再生室内注入0．1ml丝裂霉素（40μg/ml），右侧（B2）注入0．1ml层粘连蛋白（10μg／ml），第3天按上述浓度及剂量依次注入，4周进行超微结构观察。结果A1组、A2组和B2组Schwam细胞和轴突再生的超微结构明显优于B1组。结论周围神经损伤后，Schwann细胞和轴突再生之间的关系密不可分，Schwann细胞的存在与否直接影响到轴突的再生，Schwann细胞为轴突的再生提供必要的支持，且外源性层粘连蛋白能够促进Schwann细胞和轴突的再生。     

Urinary Extracellular Vesicles Carrying Klotho Improve the Recovery of Renal Function in an Acute Tubular Injury Model

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In vivo bioluminescence imaging of magnetically targeted bone marrow‐derived mesenchymal stem cells in skeletal muscle injury model

The purpose of this study is to clarify the kinetics of transplanted mesenchymal stem cells (MSCs) in rat skeletal muscle injury model and the contribution of the magnetic cell delivery system to muscle injury repair. A magnetic field generator was used to apply an external magnetic force to the injury site of the tibia anterior muscle, and 1 × 10⁶ MSCs labeled with ferucarbotran–protamine complexes, which were isolated from luciferase transgenic rats, were injected into the injury site. MSCs were injected with and without an external magnetic force (MSC M+ and MSC M? groups, respectively), and phosphate‐buffered saline was injected into injury sites as a control. In vivo bioluminescence imaging was performed immediately after the transplantation and, at 12, 24, and 72 h, and 1 and 4 weeks post‐transplantation. Also, muscle regeneration and function were histologically and electromechanically evaluated. In vivo bioluminescence imaging showed that the photon of the MSC M+ group was significantly higher than that of the MSC M? group throughout the observation period. In addition, muscle regeneration and function in the MSC M+ group was histologically and functionally better than that of the MSC M? group. The results of our study indicated that magnetic cell delivery system may be of use in directing the transplanted MSCs to the injury site to promote skeletal muscle regeneration. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 754–759, 2013     

白质星形胶质细胞内S100A4蛋白对小鼠背根神经节细胞突起生长的影响

目的 研究离体条件下白质星形胶质细胞及其表达的S100A4蛋白对小鼠背根神经节（DRG）细胞突起生长的影响。方法 用对照siRNA或S100A4siRNA转染纯的白质星形胶质细胞，3d后与成年小鼠DRG细胞共同培养6，12，18，24h，采用免疫荧光化学方法观察DRG细胞突起的生长情况。结果 在多聚-L-赖氨酸包被的盖玻片上，成熟的DRG细胞能较好地存活，但在培养24h内未见有突起长出。与白质星形胶质细胞共培养6h，各组DGR细胞均未长出突起；共同培养12，18，24h，各组DGR细胞长出突起，且突起长度随共同培养时间的延长而增加；S100A4siRNA转染组DRG细胞突起明显长于培养相同时间的对照siRNA转染组。结论 白质星形胶质细胞促进小鼠DRG细胞突起生长，而星形胶质细胞内的S100A4蛋白抑制该作用。     

移植神经的端侧吻合动物模型的制作

【目的】确定制作移植神经端侧吻合动物模型的方法并对神经再生情况进行定性检测。【方法】雌性SD大鼠,共12只,分3组建立模型分别为正常对照组、端端吻合组和端侧吻合组。术后四周行电生理检测、钳夹试验以及组织学检测。【结果】三组均有神经纤维再生通过各个吻合口。电生理检测于胫前肌均可记录到复合肌肉动作电位(CMAP),钳夹腓总神经吻合口远端时均出现疼痛避让。【结论】本研究建立了移植神经端侧吻合的动物模型,并证明在术后四周,可有神经纤维再生出现,同时再生的神经纤维具有一定的感觉与运动功能。