肾缺血再灌注细胞内钙水平与氧化应激损伤研究

目的 观察肾细胞中游离钙([Ca~(2+)]i)及氧自由基在缺血再灌注损伤过程中的改变情况,探讨二者在再灌注肾损伤中发生作用机制。方法 摘除Wistar大鼠左肾,钳夹右侧肾蒂,建立急性缺血再灌注肾损伤模型,应用Fura-2/AM荧光指示剂测定缺血再灌注大鼠肾细胞内[Ca~(2+)]i浓度的变化,同时测定谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果 缺血再灌注不同时期肾细胞内[Ca~(2+)]i浓度均有不同程度增高,与对照组相比差异有显著意义,各实验组SOD活力水平降低,与对照组相比差异有显著意义,MDA生成高于对照组,GSH-Px在再灌注早期活力减弱,明显低于对照组,晚期活力基本恢复。结论 1.缺血再灌注不同时期大鼠肾细胞内[Ca~(2+)]i超载和不同程度的氧化侵袭,在缺血再灌注肾损伤病理过程中起重要作用;2.再灌注时间与肾细胞内[Ca~(2+)]i超载呈正相关,提示再灌注损伤通过不同机制加重细胞钙超载。     

基于C-V模型和MRF的脑部MRI分割

为准确分割脑部磁共振图像(MRI)的灰质、白质和背景,提出一种基于C-V模型和马尔可夫随机场的全自动分割方法。采用C-V模型与形态学相结合的方法对脑MRI进行预处理,去除多余脑组织,获得待分割图像。引入灰度场局部熵的思想对惩罚因子进行估计,利用马尔可夫随机场模型建模实现脑灰白质的分割,并运用形态学方法获得最终分割结果。对96幅IBSR图像和46幅临床图像进行实验,结果表明,该方法能够实现脑部MRI灰白质的全自动分割,且具有较好的分割精度和较快的处理速度。     

Simulation of the Impact Between Head and Seat Head Restraint During REC Under Consideration of the Multiphase and Nonlinear Features

The impact process between car drivers head and seat head restraint during a car rear end collision is simulated, where the multiphase and nonlinear features of the human brain tissues and the foam material of the seat head restraint are considered. Using the FEM-software LS-DYNA, the brain tissue deformation caused by a car REC is calculated. The purpose of this work is to supply references for improving the design of the head protective devices. The results show that the maximum shear strain appears near the boundaries of different phases and there is a great shear strain gradient in the brain tissues.     

Evaluation of PLGA/chitosan/HA conduits for nerve tissue reconstruction

A micro-envioment for nerve cells and tissue growth were designed and constructed via surface modification of poly(L-lactide-co-glycolide)(PLGA) with chitosan and hydroxyapatite(HA). The poly(L-lactide-co-glycolide)/chitosan/hydroxyapatite (PLGA/chitosan/HA) conduits were manufactured by a combined solvent casting and particulate leaching technique. The conduits were highly porous with an interconnected pore structure and 76.5% porosity. Micropores with 50–100 micrometer diameter were formed in the conduits. In vivo application of PLGA/chitosan/HA conduits for reconstruction of 10 mm sciatic nerve defect was assessed by the walking track analysis, the quantifying of the wet weight of tibialis anterior muscle and the histological assessment. The conduits in host rats in vivo can not only be an effective in promoting regenerating of nerves but can also lead to favorable nerve functional recovery. Funded by the National Natural Science Foundation of China(No.50774096)     

Design and preparation of bone tissue engineering scaffolds with porous controllable structure

A novel method of designing and preparing bone tissue engineering scaffolds with controllable porous structure of both macro channels and micro pores was proposed. The CAD software UG NX3.0 was used to design the macro channels’ shape, size and distribution. By integrating rapid prototyping and traditional porogen technique, the macro channels and micro pores were formed respectively. The size, shape and quantity of micro pores were controlled by porogen particulates. The sintered β-TCP porous scaffolds possessed connective macro channels of approximately 500 μm and micro pores of 200–400 μm. The porosity and connectivity of micro pores became higher with the increase of porogen ratio, while the mechanical properties weakened. The average porosity and compressive strength of β-TCP scaffolds prepared with porogen ratio of 60wt% were 78.12% and 0.2983 MPa, respectively. The cells’ adhesion ratio of scaffolds was 67.43%. The ALP activity, OCN content and cells micro morphology indicated that cells grew and proliferated well on the scaffolds. Funded by the Postdoctor Science Fund of China (No. 20070410715) and Shanghai Excellent Youth Special Fund (No. 17014)     

运用实时荧光定量RT-PCR检测人正常组织及肿瘤组织中BRDT表达

目的探讨BRDT基因在正常组织及癌组织中的分布及其作为肿瘤治疗靶分子的可能性。方法运用实时荧光定量PCR方法分析BRDT在人正常组织及癌组织中的表达,使用18S rRNA作为内对照。结果在所检测的正常组织中该蛋白的mRNA只存在于睾丸组织中,而在其它组织不表达;在检测的10例胃腺癌组织标本中,有6例mRNA的微弱表达;在检测的10例食管鳞状细胞癌组织标本中,有3例mRNA的微弱表达;在检测的12例子宫颈鳞状细胞癌组织标本中均未有表达;在检测9例子宫内膜腺癌组织标本中,有2例微弱表达;在检测12例脑癌组织标本中,只有1例微弱表达。结论BRDT不可能作为子宫颈鳞状细胞癌、脑癌、子宫内膜腺癌及食管鳞状细胞癌治疗的潜在分子靶点,是否能够做胃腺癌的靶点还需进一步探讨。     

油酸二聚甘油酯的合成及其柔软保湿纸的测试

以油酸缩水甘油酯和甘油为原料，在固体酸催化剂（活性炭负载硫酸）作用下，通过开环反应制得油酸二聚甘油酯。通过FTIR和1HNMR对产物结构进行表征，并将其用作柔软保湿剂涂覆到面巾纸上对纸张的柔软度、保湿性、抗张强度等性能进行测试。结果表明：油酸二聚甘油酯具有优异的柔软保湿性能，在油酸二聚甘油酯添加量为甘油水溶液质量的0.25%时，面巾纸的柔软度（49 mN）优于市面上有机硅柔软剂改性的面巾纸柔软度（68 mN），这是由于大分子柔软剂能够对纤维表面的缺陷进行修复，从而使纤维表面平整度的提升。且在温度为30 ℃，湿度为60%时，油酸二聚甘油酯型柔软保湿剂涂覆后的面巾纸的保水率（98.2%）也略高于有机硅柔软剂涂覆后的面巾纸的保水率（96.5%）。     

基于STM32的植物补光调控系统设计

光照是植物生长和发育的重要环境因子之一,在植物组织培养过程中,为了更好地利用LED光源对组培室内植物进行补光,节约能源和提高补光效率,设计了一种基于STM32的植物补光调控系统;系统采用STM32作为微控制器,设计植物补光总控中心和补光调控节点电路,补光总控中心通过RS485通信模块与安装在组培室内的多个补光调控节点进行指令和数据的通信,补光调控节点根据补光总控中心的任务指令和补光参数,协调补光调控节点的各个电路模块之间相互工作,实现按时、按量对组培室内的植物进行补光;经过实验测试结果表明,该系统环保、易操作且性能稳定可靠,能够实现补光的同时节约能源,进而减少了组培室的育苗成本,为在植物组培室内实现植物的补光提供参考。     

Periodontal ligament cells cultured on the tricalcium phosphate/chitosan scaffolds in vivo and in vitro

To search suitable scaffolds for periodontal tissue regeneration, different ratios of tricalcium phosphate/chitosan(TCP/chitosan) scaffolds were prepared through a freeze-drying process. Human periodontal ligament cells(HPLCs) were incubated on the scaffolds in vitro. Cells were cultured on the scaffolds, detected by scanning electron microscopy (SEM). HPLCs were analyzed by MTT assay and alkaline phosphatase(ALP) activity detection. HPLCs were seeded onto the scaffolds. Then these scaffolds with HPLCs were implanted subcutaneously into athymic mice. The state of periodontal tissue regeneration was detected after 4 weeks. As the ratio of TCP increased, TCP/chitosan scaffolds accelerated HPLCs proliferation significantly higher than the pure chitosan scaffold. HPLCs produced the cementoid tissue in vivo. The periodontal tissue regeneration engineering is able to be applied with TCP/chitosan scaffolds.     

基于交互式图割算法的结肠组织提取

针对腹部CT医学图像中结肠组织自身局部特征的问题,研究了一种基于交互式Graph Cuts结肠组织的分割方法。首先人工标定一部分体素标记为＂目标＂和＂背景＂种子点。然后将图像映射成网络图,通过相邻像素间的灰度特征分配边的权重值,采用26邻域系统实现三维图像的分割。最后使用最大流/最小割方法最小化能量函数,得到结肠区域。实验结果表明,交互式的图割算法能够准确地从三维腹部CT医学图像中提取出结肠组织,体现了结肠数据的局部特征。算法能自动将所有腹部CT切片的结肠组织分割出来,实验获得的结果有利于结肠病变的发现和精确定位。