组织工程软骨生物反应器的设计

目的 根据流体力学原理优化反应器内腔结构,并设计一套组织工程软骨生物反应器.方法 采用计算机仿真的方法对反应器内腔流场进行仿真计算,通过流场分析确定内腔结构,最终构建一套完整的生物反应器系统.结果 确定了生物反应器的内腔结构,生物反应器由控制系统和细胞培养室两部分构成,能置于培养箱中对软骨细胞材料复合物进行动态培养.结论 反应器内腔的结构是合理的.整个生物反应器系统运行可靠.     

组织工程软骨生物反应器的设计

目的 根据流体力学原理优化反应器内腔结构,并设计一套组织工程软骨生物反应器.方法 采用计算机仿真的方法对反应器内腔流场进行仿真计算,通过流场分析确定内腔结构,最终构建一套完整的生物反应器系统.结果 确定了生物反应器的内腔结构,生物反应器由控制系统和细胞培养室两部分构成,能置于培养箱中对软骨细胞材料复合物进行动态培养.结论 反应器内腔的结构是合理的.整个生物反应器系统运行可靠.     

182例造血干细胞移植患者入住附带千级卫生间的百级层流病房满意度调查分析

目的:通过调查分析入住附带千级卫生间的百级层流病房患者的满意度,以达到层流病房设计的合理化,人性化,为层流病房的建设提供依据。方法:对2009年1月～2011年12月入住附带千级卫生间的百级层流病房的造血干细胞移植患者182例进行问卷调查分析。结果:182例患者96%以上对附带千级卫生间的百级层流病房的人性化设计满意,能满足患者人性化的需求。结论:附带千级卫生间的百级层流病房设计合理,能满足患者人性化的需要,患者满意,可以推广建设使用。     

碟形血泵内部流场的数值仿真与优化

目的优化儿童用碟形血泵的血液动力学性能。方法应用计算流体仿真技术(computational fluid dynamics,CFD)对儿童用碟形血泵内的流场进行数值模拟,通过分析数值计算结果对其产生的血栓和溶血现象进行系统的分析研究,根据流场分析结果对现有血泵结构方面的不足实施改进。结果选取2 500 rpm、3 000 rpm和4 000 rpm三个不同转速对血泵流场进行了CFD模拟,每个转速下选取5个不同的流量出口边界条件,仿真结果与实验数据吻合;血泵的增加效果良好,但在低转速区域叶片表面存在流动分离的情况增加。剪切力的最大值基本维持在100 Pa以内。结论该设计碟形血泵流体力学性能较好,流线控制较好,对血栓和溶血的控制理想。但有流叶分离的情况发生,有进一步改进的空间。     

高速分件供送螺杆装置的理论与设计

本文着重阐述高速分件供送螺杆装置的有关理论与设计的一些关键性问题。其中包括:合理设计变螺距螺杆的新的分析计算方法,以及被供送物件或容器实现稳定运动的可控条件。     

整理箱应用于手术室器械台的整理布局与无菌保持

目的:探讨手术间层流不同角度与方式对手术间的无菌保持要求以及层流手术间无菌保持要求对植入术无菌管理的影响。方法:将不同级别层流手术间采取相同方法检测无菌状态。结果:层流手术室不同布局对于层流无菌的保持有显著差异。结论:层流手术室不同布局(手术室器械台整理箱应用)有益于层流无菌的保持。     

流动激活血管内皮细胞中转录因子核因子-кB和激活蛋白-1的表达

目的比较血管内皮细胞(endothelial cells,ECs)在不同流场中转录因子核因子-кB(nuclear factor-кB,NF-кB)和激活蛋白-1(activator protein-1,AP-1)的表达规律,为力学信号对基因调控模式的影响提供依据。方法将培养的人脐静脉ECs加载于层流和湍流的离体流室模型中,以作用时程的不同分为6个时间点(0.5 h、1 h、2 h、3 h、4 h和5 h),运用共聚焦显微镜,从蛋白水平观察ECs中NF-кB和AP-1在不同流室中表达的时间规律和空间规律。结果层流中NF-кB的表达高峰出现在1 h段(26.49±1.63,P<0.05),随后转行向下;湍流中NF-кB表达在3 h段升至峰值(34.41±6.43,P<0.05);层流中c-Jun/AP-1表达一过性增高,0.5 h到达峰值(18.95±5.38,P<0.05),随即下降至基线水平;湍流中c-Jun/AP-1表达呈持续缓慢上升趋势(P<0.05)。结论湍流流场对血管ECs中NF-кB和AP-1表达的影响不同于层流,湍流对NF-кB和AP-1的持续激活上调作用可能引起了ECs形态结构和功能行为的病理学改变。     

应用牵张成骨技术(DO)整复腭裂实验动物模型的建立

目的:建立长期、稳定的腭裂动物模型,并可用于以DO成骨方式进行畸形矫治。方法:1-1.5岁杂种犬7只为实验对象,其中以2只为实验对照组,以外科手术形成硬腭部8mm×30mm全层洞穿缺损裂隙。8周后观察裂隙软、硬组织形态。5只为实验组,在形成模型的同时放置固定DO装置,并形成骨转移盘,观察模型建立后牵张成骨的可行性。结果:实验犬手术后均成活、健康状况良好,实验对照组犬8周后上腭裂隙仍存在,干骨标本见骨缺损大小形状与手术时无差别,实验组犬安置DO装置后伤口愈合良好,DO装置固定牢靠。结论:通过手术方式建立的腭裂动物模型,经长期观察裂隙不能自行修复,安置DO装置后效果稳定。腭裂DO装置设计较合理,建立的DO矫正腭裂模型具有充分的可行性。     

流动对兔动脉缩窄区域内皮细胞形态的影响

目的：在体考察不同流场环境中血管内皮细胞形态学和完整性的改变，及其与流场的空间相关性。方法：将10只大耳白兔分成动脉缩窄组和对照组，建立兔颈总动脉环缩狭窄，使用脉冲多普勒超声系统考察缩窄下游的湍流流场及对侧血管的层流流场；用扫描电子显微镜探测内皮细胞（ECs)计数、形状指数和定向角等形态学指标。结果：缩窄下游的湍流流场中ECs大量脱落，细胞下基质和胶原组织暴露，ECs变形，无明显定向性。越远离缩窄，ECs的残留率越高，细胞也逐渐重新建立了定向性。结论：缩窄血管下游的湍流流动是导致血管ECs形态结构异常和损伤的重要原因。     

组织工程小血管摩擦力测量方法的研究与应用

目的设计一套用于组织工程小血管内壁摩擦力测量的装置并对组织工程血管的材料进行初步的测量,以验证装置的可靠性和相关结论。方法根据血液动力学的原理,对血管的力学模型进行分析,确定组织工程血管内皮细胞摩擦力的测量方法,从而设计完成整套装置并对弹性元件进行测量,并进行组织工程降解材料聚羟基乙酸PGA构成的管状支架进行摩擦力的测量。结果设计完成了测量组织工程血管内壁摩擦力的实验装置,弹性元件的牵拉力与位移的关系呈良好的线性关系。聚羟基乙酸PGA管状支架的摩擦力随流速的增加而增加。结论测量组织工程血管内壁摩擦力的实验装置是可行的,聚羟基乙酸PGA管状支架的摩擦力与流速基本呈现线性关系。     

Evaluation of energy dissipation rate as a predictor of mechanical blood damage

A long‐standing goal in the field of biofluid mechanics has been to reliably predict hemolysis across the wide range of flows that can occur in prosthetic cardiovascular devices. A scalar representation of the complex three‐dimensional fluid stresses that are exerted on cells is an attractive alternative for the simplicity that it lends to the computations. The appropriateness of the commonly used von‐Mises‐like scalar stress as a universal hemolysis scaling parameter was previously evaluated, finding that erythrocyte membrane tensions calculated for laminar shear and extensional flows and for three cases of turbulent flow were widely divergent for the same value of scalar stress. The same techniques are applied in this study to laminar and turbulent flows that each have the same energy dissipation rate. Results showed that agreement of membrane tension between laminar shear and turbulent shear inside an eddy was improved relative to the common scalar stress cases, but disagreement between laminar shear and laminar extension remained the same and disagreement between laminar shear and other turbulent flows increased. It is therefore concluded that energy dissipation rate alone is also likely not sufficient to universally scale blood damage across the range of different flows that can be encountered clinically.     

长期体外培养对人脂肪源性间充质干细胞生物学特性的影响

目的通过观察长期体外培养对人脂肪源性间充质干细胞(ADSCs)生物学特性的影响,鉴定ADSCs作为组织工程种子细胞的优越性。方法通过流式细胞技术观察长期体外培养对人ADSCs表面抗原表达和凋亡的影响。通过碱性磷酸酶染色、Von Kossa染色及RT-PCR检测长期体外培养对人ADSCs成骨分化潜能的影响。结果原代ADSCs表面高表达间充质干细胞表面标记物,而不表达血源性细胞表面标记物,标记物不随传代次数变化。早期ADSCs凋亡率为1%～2%,随传代次数增多凋亡率逐渐增加．但幅度不大。碱性磷酸酶染色、Von Kossa染色和RT-PCR检测显示ADSCs传至第8代时仍能保持成骨分化潜能。结论ADSCs生物学特性稳定,是较为理想的组织工程及再生医学研究的种子细胞。     

Response of arterial smooth muscle cells to laminar flow.

This study was designed to determine whether laminar flow influences the proliferation rate and morphology of smooth muscle cells (SMC) in culture. Bovine aortic SMC were subjected to a shear stress of 6 dyne/cm2. The control group was subjected to similar incubation conditions without flow. Flow cytometry demonstrated decreased proliferation rate in SMC subjected to laminar flow. This phenomenon was still evident 24 hours after flow cessation. SMC were examined by light and electron microscopy. SMC subjected to laminar flow aligned along the direction of flow assuming a spheric morphology. These changes were reversible after a 48-hour resting period. The degree of organization of actin, tubulin and other microfilaments was evaluated by indirect immunofluorescence. SMC subjected to shear stress showed a clear reorganization of the cytoskeleton with expression of stress fibres. These changes were reversible after a 48-hour resting period. These findings may contribute to understanding the mechanisms by which SMC in vivo respond to forces generated by blood flowing under pressure.     

Lattice Boltzmann Study of Flow and Temperature Structures of Non-Isothermal Laminar Impinging Streams

Previous works on impinging streams mainly focused on the structures of flow field, but paid less attention to the structures of temperature field, which are very important in practical applications. In this paper, the influences of the Reynolds number (Re) and Prandtl number (Pr) on the structures of flow and temperature fields of non-isothermal laminar impinging streams are both studied numerically with the lattice Boltzmann method, and two cases with and without buoyancy effect are considered. Numerical results show that the structures are quite different in these cases. Moreover, in the case with buoyancy effect, some new deflection and periodic structures are found, and their independence on the outlet boundary condition is also verified. These findings may help to understand the flow and temperature structures of non-isothermal impinging streams further.     

Peyronie's disease cell culture models: phenotypic,genotypic and functional analyses

Peyronie's disease is a fibromatosis of the tunica albuginea. While trauma is believed to be the inciting event, the exact pathophysiology of this condition is unknown. In vitro analysis of cell biology can shed light on the pathogenesis of medical conditions and has been used for many decades as a research tool. We have established a cell culture model, which we have used to study the pathobiology of cells derived from Peyronie's disease plaque tissue. In 10 separate cell cultures derived from different individuals, these cells have demonstrated consistent phenotypic, genotypic and functional alterations. In neither of the control cell cultures, neonatal foreskin fibroblasts and normal tunica-derived fibroblasts have any of the above aberrations been demonstrated. The cells studied have been shown to be fibroblasts in nature with a sub-population of myofibroblasts present in culture. The Peyronie's disease plaque tissue-derived fibroblasts have demonstrated (i) consistent morphologic transformation (ii) increased S-phase on flow cytometry (iii) decreased dependence on culture medium (iv) cytogenic instability (v) excess production of fibrogenic cytokines and (vi) stabilization and dysfunctionalization of p53. Further refinement of this model and future analyses may permit an increased understanding of the pathogenesis of this condition and allow the development of therapeutic strategies.     

不同切应力下血管内皮整合素αVβ3的表达

目的对离体培养血管施加不同水平切应力,观察不同时间点整合素αVβ3(αVβ3-Integrin)的表达水平。方法 (1)建立血管体外应力培养系统,检测不同切应力时流场的稳定性;(2)将家兔50只按完全随机分组方式分为两组(n=25):低切应力组(5 dyn/cm2)和正常切应力组(20 dyn/cm2),每组再完全随机等分为2 h、4 h、8 h、16 h和24 h共5个时间点(n=5),取兔降主动脉并将其置于应力培养系统进行离体培养,采取免疫组织化学染色法观察两组5个不同时间点的整合素αVβ3表达部位及强度。结果建立的体外血管应力培养系统运行稳定,能够提供实验所需的各种切应力。低切应力组的整合素αVβ3在5个时间点都有较高程度的表达,并在16 h时达到高峰,其平均光密度值[MOD=(1.995±0.194)×10-2]明显增高(P<0.05);正常切应力组随时间的增加逐渐减少,2 h[(0.059±0.005)×10-2]、4 h[(0.049±0.002)×10-2]时分别与其他时间点相比差异有统计学意义(P<0.05)。低切应力组的整合素αVβ3MOD值与正常切应力组相同时间点比较明显增高(P=0.000)。结论低切应力可引起αVβ3明显表达,而正常切应力抑制αVβ3的表达。     

绿脓杆菌制剂对人肝癌MHCC97L细胞增殖和侵袭能力的影响

目的 探讨绿脓杆菌制剂(pseudomonas aeruginosa vaccine,PA)对有转移潜能的人肝癌MHCC97L细胞增殖和侵袭能力的影响.方法 采用不同浓度的PA分别作用于MHCC97L细胞,观察细胞增殖、生长曲线、克隆形成率、流式细胞术分析(FCM)、侵袭、运动、迁移、VEGF和MMP2蛋白表达(ELISA法).结果 PA明显抑制MHCC97L细胞增殖和克隆形成,呈良好的剂量-效应关系.PA 48 h和72 h的IC50分别为3.1×108/ml和1. 9×108/ml.PA浓度为0.5×108/ml、1×108/ml和2×108/ml时,其细胞倍增时间依次增加,克隆形成率依次降低(P均＜0.01);FCM显示,G1期细胞比例随PA浓度增加而增加,S+G2期细胞比例随PA浓度增加而降低(P均＜0.01).PA浓度为1×108/ml时,穿过人工基底膜(侵袭实验)和上室底膜(运动实验)的细胞数(分别为4.8±1.3和8.8±2.2)明显低于对照组(8.6±2.1和15.6±1.2)(P均＜0.01);细胞经72 h培养后,对照组划痕逐渐愈合,1×108/ml的PA组细胞划痕依然明显.ELISA法检测发现,1×108/ml的PA组其VEGF蛋白和MMP2蛋白含量和对照组相比均无明显差异(P均＞0.05).结论 在一定条件下,绿脓杆菌制剂可抑制人肝癌MHCC97L细胞增殖和克隆形成,其作用部分是通过使细胞周期阻滞在G1期实现的;绿脓杆菌制剂可以明显抑制MHCC97L细胞的侵袭、运动和迁移能力,其作用和VEGF、MMP2蛋白分泌关系不明显.