心肌组织工程种子细胞的研究进展

目的 综述组织工程心肌种子细胞来源的研究现状与存在的问题,并展望其前景.方法 广泛查阅近十年来有关组织工程心肌种子细胞的文献,并进行综述.结果 心肌组织工程的替代治疗具有极其诱人的前景,但还处于起步阶段,仍然需要通过大量的实验找到最佳的细胞来源.结论 组织工程心肌有广阔潜在的临床应用前景,其细胞来源值得进一步研究.     

组织工程化子宫片层构建的实验研究

目的利用组织工程方法体外构建了与子宫壁内膜和肌层相近的子宫片层。方法将分离培养的兔子宫平滑肌细胞和基质细胞分别与液态Ⅰ型胶原支架材料混合,依次接种于自制静态力学拉伸模具中,再将上皮细胞接种在基质层上,形成组织工程化子宫组织。采用组织学和免疫组织化学方法观察所构建的组织工程化子宫的组织学特征,扫描电镜检测上皮细胞微结构。结果分离培养的兔子宫平滑肌细胞、基质细胞和内膜上皮细胞的纯度均达到95％以上。在静态力学拉伸下培养14天后,在胶原凝胶上生长的平滑肌细胞和基质细胞按拉伸方向有序排列,上皮细胞生长在最上层。激素处理后,扫描电镜观察显示上皮细胞表面有羽状突或纤毛,并且附有大量的微绒毛。结论由平滑肌细胞、基质细胞、上皮细胞和Ⅰ型液态胶原构建,并经静态力学拉伸构建的组织工程化子宫片层能较好地模拟自然子宫的形态结构和功能。     

筛选适宜于构建工程化肝组织的凝胶材料支架

目的使用不同可注射性凝胶支架体外进行新生大鼠肝细胞立体培养,为后期体内植入筛选相容性较好的支架材料。方法使用胰酶冷消化法分离新生大鼠肝细胞。将肝细胞分别与纤维蛋白胶、壳聚糖凝胶、鼠尾胶原、透明质酸钠支架材料复合,形成工程化肝组织凝胶,接种于培养板中,并通过定期光镜来观察大鼠肝细胞,四唑盐(MTT)比色法评价细胞活性。溴甲酚绿法测上清白蛋白含量,脲酶比色法测定上清尿素含量。结果四组均可形成三维生长的工程化类肝样组织。培养第4天,生物蛋白胶及壳聚糖组的培养上清液中尿素含量达到高峰,分别为培养第1天的1.31倍和1.28倍,随后含量缓慢下降。培养第7天,新生大鼠肝细胞在纤维蛋白凝胶及壳聚糖凝胶中密集生长,同时MTT显示细胞活性及白蛋白分泌达到高峰,OD值分别为培养初期的1.11倍和1.17倍,上清白蛋白含量分别是初期的1.13倍和1.15倍。而在透明质酸钠及鼠尾胶原凝胶中则细胞生长缓慢,白蛋白及尿素含量持续下降。结论 4种可注射性支架中,壳聚糖和生物蛋白胶对于新生大鼠肝细胞生物相容性较好,透明质酸和鼠尾胶原较差,前两者更适合用于工程化肝组织的构建。     

犬肺移植中供体肺组织形态学与超微结构计量学研究

目的：观察改进EC液低温灌注犬肺离体保存肺组织随保存时间变化而产生的结构变化。方法：4℃EC液灌注6只健康成年杂种犬肺并离体低温保存，灌注结束后保存30、60、120、180、240min取材制作组织标本，观察不同时点肺组织形态学变化，测试肺组织湿干重比(W／D)与肺泡上皮细胞核的体积密度(vv)、表面积密度(Sv)、表面积与体积比(Rsv)，并以灌注前为对照组。结果：随保存时间延长肺组织细胞水肿渐趋明显，肺组织W／D、肺泡上皮细胞核的Vv、Sv、Rsv实验组与对照组相比差异无显著性(P＞0．05)。结论：Vv、5v、Rsv可作为肺保存过程中评价损伤程度的客观指标，改进后的EC保存液可用于供体肺保存。     

组织工程心肌研究中心肌肌钙蛋白T及细胞间隙连接蛋白43免疫组化检测结果的观察与分析

目的 建立组织工程心肌研究中系统观察免疫组化检测结果的程序与方法.方法 取新生大鼠心脏制作石蜡组织切片;用0.25%胰酶消化法分离原代新生大鼠心肌细胞,一部分进行细胞爬片培养,一部分与液态胶原混合构建组织工程心肌并施加力学拉伸刺激,制作组织工程心肌石蜡组织切片.对三者分别进行心肌肌钙蛋白T(cTnT)及细胞间隙连接蛋白43(Cx43)抗体的免疫组化染色.比较观察天然心肌组织、体外培养心肌细胞及组织工程心肌组织免疫组化的检测结果,对其形态结构的变化进行综合分析.分别选取5个不同视野对细胞总数和cTnT阳性细胞进行计数,计算百分比.在细胞和再造心肌组织培养过程中观察自发收缩的细胞区域与cTnT着色区域的关系.结果 天然心肌和组织工程心肌切片分别反映了天然在体心肌和体外构建心肌的细胞形态和组织结构特征;心肌细胞爬片显示了体外心肌细胞与非心肌细胞的形态,以及随体外培养时间的延长其形态和数量比例的改变.细胞在体外培养时间越长,成纤维细胞比例越高.尽早将分离的原代新生大鼠心肌细胞与液态胶原混合体外再造心肌组织进行三维拉伸培养有助于抑制其中的成纤维细胞的增殖速度.将分离细胞爬片培养4h后可相继观察到能自发收缩的细胞,其收缩区域与染色片中cTnT的着色区域基本相符;再造的组织工程心肌的收缩自拉伸后48h开始,逐渐从单个细胞到肌柬再到整条再造心肌,频率逐渐加快,从1～2/min到5～10/min.结论 建立了观察与分析组织工程心肌免疫组化结果的程序和方法,为优化实验设计与条件提供了客观参数,也为构建其他组织的形态学观察与分析方法提供了有利借鉴.     

模拟微重力动态培养构建组织工程化软骨修复猪关节软骨缺损研究

目的:通过大型动物实验探讨模拟微重力动态培养系统构建组织工程化软骨修复关节软骨缺损的效果。方法:10~12月龄的五指山猪8头,分别在每头猪髌骨切迹上建立4个软骨缺损模型,左右膝关节各2个缺损,共32个,取缺损位置的软骨组织进行细胞分离培养扩增后复合三维Ⅰ型胶原上,分别置于旋壁式生物反应器与培养板中培养7 d,一方面取适量的样本进行HE染色、DAPI染色检测;另一方面将复合物回植修复猪关节缺损。每头猪关节缺损随机分为4组:微重力动态培养组(A)、普通静态培养组(B)、单纯支架组(C)、空白对照组(D),每个膝关节随机分配两组。术后12周处死实验动物,取实验标本进行核磁共振(MRI)、大体观察及组织学检测。结果:MOCART核磁共振评分:A组为74.37±3.90、B组为66.87±4.96、C组为58.75±3.30、D组为43.12±3.47,差异具有统计学意义(P<0.05);O’Driscoll组织学评分:A组为16.00±1.41、B组为12.37±1.69、C组为8.37±0.83、D组为3.25±1.26,各组之间差异具有统计学意义(P<0.05)。结论:模拟微重力动态培养模式构建的组织工程化软骨较普通培养更有利于软骨缺损的修复。     

骨髓基质细胞与钙磷陶瓷复合构建组织工程化骨组织

目的：利用组织工程学原理和方法新生骨组织,为骨组织工程选择适宜的细胞来源与细胞载体,方法：将免骨髓基质细胞（bone marrow stromal cell,BMSc)进行体外培养,通过表态学观察和组织化学检测,分为生物活性玻璃陶瓷（hioactive galss ceramic,BGC)复合细胞组和单纯细胞性,进行细胞增残,碱性磷权酶检测,将两者复合后植入免自体肌袋内,分单纯材料接种组和复合材料接种组,于不同时间取材,ＨＥ染色,观察其成骨过程,结果：骨髓基质细胞在体外培养时表现出与成骨细胞相似的形态学与功能表现,ＢＧＣ利用细胞的生长繁残,对细胞的功能表现无明显影响,ＢＭＳc与ＢＧＣ复合植入体内可产生成熟骨组织,结论：利用ＢＧＣ与ＢＭＳc复合可产生组织工程化新生骨组织。     

采用温敏性壳聚糖水凝胶体外构建组织工程化软骨的实验研究

目的 验证自行制备的温敏性壳聚糖水凝胶作为软骨细胞支架材料构建组织工程化软骨的可行性.方法 以壳聚糖、β-甘油磷酸钠和羟乙基纤维素为原料,制备温敏性壳聚糖水凝胶,通过SD大鼠肌内注射植入,进行组织相容性检测.在此基础上,将其与软骨细胞复合构建组织工程化软骨,观察软骨细胞在壳聚糖水凝胶中的存活情况,并于体外培养3周后,作相关组织形态学检测.结果 制备的壳聚糖水凝胶具有温度敏感性,即室温时为液态,37℃时10～15min可发生交联反应成为固态凝胶.SD大鼠肌内注射不同时间点组织相容性检测表明,该材料具有良好的组织相容性,植入体内2、4周时有少量炎性细胞浸润,6周时材料降解明显,8周时已经基本降解.采用该材料构建的组织工程化软骨体外培养3周后取材,通过组织学检查,HE染色可观察到软骨陷窝样结构,甲苯胺蓝染色、番红O染色及免疫组化染色结果显示软骨细胞具有分泌细胞外基质的功能.结论 本研究自行制备的温敏性壳聚糖水凝胶材料具有良好的组织相容性,将其与软骨细胞复合后,可以在体外再造组织工程化软骨,是一种有广泛应用前景的软骨组织工程支架材料.     

组织工程化人工胆管材料学研究进展

近年来,随着临床对胆道远端Oddi括约肌功能的逐步重视,各种形式的胆道修复术得到了发展.目前国内开展的多为自体组织修复,如带血管蒂胆囊瓣、胃瓣、空肠瓣等胆道修复.但由于自体组织必须取自健康部位,增加了创伤,且远期疗效尚不肯定,而同种异体或异种移植又存在难以避免的免疫排斥,人工材料因此成为克服组织缺损的第三种选择.随着高分子材料学及组织工程学技术的不断发展,学者们开始致力于新型胆道修复材料的基础研究及动物实验.     

A real-time system for multi-image gated cardiac studies

A minicomputer-based system is described that allows real-time construction and simultaneous display, in flicker-free movie format, of a cardiac-cycle-spanning sequence of ECG-gated scintigraphic images. In as little as 2 min, the endless-loop flicker-free movier clearly displays cardiac anatomy, time-dependent volume variations of cardiac chambers, and abnormalities of cardiac wall motion that would be difficult or impossible to detect from static gated images. Simultaneously, a time-activity curve with high temporal resolution can be generated from a previously defined region of interest, thereby quantifying additional parameters of cardiac function. Because the movie and time-activity curve are displayed in real time and require only a short data-collection interval to achieve statistical reliability, the physician can use the system interactively, modifying the form, intensity, or duration of diagnostic and therapeutic interventions based on the observed response. This system is well suited for intervention studies, for continuous cardiac monitoring, and for the rapid screening of patients with suspected cardiac disease.     

骨组织工程的研究进展

本文涉及骨组织工程的四个方面：（1）种子细胞的来源、性质；（2）细胞外基质替代物的开发；（3）适宜的培养环境；（4）组织工程化骨组织的应用。在此笔者对骨组织工程的进展作一综述，并探讨其存在的问题和发展前景。     

A tissue engineered osteochondral plug: an in vitro morphological evaluation

Articular cartilage lesions have a poor intrinsic healing potential. The repair tissue is often fibrous, having insufficient biomechanical properties, which could frequently lead to the development of early osteoarthritis. In the last decade, tissue engineering approaches addressed this topic in order to restore joint function with a differentiated and functional tissue. Many biomaterials and techniques have been proposed and some of them applied in clinical practice, even though several concerns have been raised on the quality of the engineered tissue and on its integration in the host joint. In this study, we focused on engineering in vitro a biphasic composite made of cellular fibrin glue and a calcium–phosphate scaffold. Biphasic composites are the latest products of tissue engineering applied to articular cartilage and they seem to allow a more efficient integration of the engineered tissue with the host. However, a firm in vitro bonding between the two components of the composite is a necessary condition to validate this model. Our study demonstrated a gross and microscopic integration of the two components and a cartilage-like quality of the newly formed matrix. Moreover, we noticed an improvement of this integration and GAGs production during the in vitro culture.     

军事医学的工程思维与工程系统管理

论文的研究目的是建立军事医学的工程思维方式与工程系统管理范式。作者运用系统论的思想方法,论述了军事医学工程思维的必要性、特点和应用;研究提出了军事医学工程系统管理的内涵、特点、应用和实施策略;探讨了军事医学的工程创新。     

Clinical application of scaffolds for cartilage tissue engineering

The purpose of this paper is to review the basic science and clinical literature on scaffolds clinically available for the treatment of articular cartilage injuries. The use of tissue-engineered grafts based on scaffolds seems to be as effective as conventional ACI clinically. However, there is limited evidence that scaffold techniques result in homogeneous distribution of cells. Similarly, few studies exist on the maintenance of the chondrocyte phenotype in scaffolds. Both of which would be potential advantages over the first generation ACI. The mean clinical score in all of the clinical literature on scaffold techniques significantly improved compared with preoperative values. More than 80% of patients had an excellent or good outcome. None of the short- or mid-term clinical and histological results of these tissue-engineering techniques with scaffolds were reported to be better than conventional ACI. However, some studies suggest that these methods may reduce surgical time, morbidity, and risks of periosteal hypertrophy and post-operative adhesions. Based on the available literature, we were not able to rank the scaffolds available for clinical use. Firm recommendations on which cartilage repair procedure is to be preferred is currently not known on the basis of these studies. Randomized clinical trials and longer follow-up periods are needed for more widespread information regarding the clinical effectiveness of scaffold-based, tissue-engineered cartilage repair.     

组织工程在创伤修复中的应用

创伤修复涉及到自体、同种异体组织移植及人工材料替代。上世纪80年代中期出现的组织工程学,为创伤修复提供了新的方向,即用活的细胞接种在可降解支架材料上,经体外培养后植入体内,修复组织缺损,重建功能。本文根据最新文献,介绍了组织工程的主要基础研究成果及临床应用的经验。     

A longitudinal analysis of morphological characteristics and body proportionality in young elite sprint paddlers

ABSTRACT

Introduction: There are certain anthropometric attributes common to most high-level paddlers and among the determinants for optimal performance consecution in senior categories.

Objective: The present investigation aimed to determine the evolution of morphological characteristics of elite paddlers during adolescence and to compare them with the values exhibited by Olympic competitors.

Methods: In a longitudinal study, thirteen young elite paddlers (seven boys and six girls) completed a battery of anthropometric tests (heights, weight, girths, lengths, and sum of skinfolds) and on-water performance assessments (200 and 500 m) during three consecutive years.

Results: Body mass and upper body sizes significantly change over the years (p < .05), especially in boys. Both male and female paddlers presented significant differences and large effect sizes in muscle mass and skin mass values (η²_p > .64) whereas bone mass and fat mass remained stable from the 1st to the 3rd year. Proportionality analysis revealed girths and breadths differences in arm and chest variables as well as large effect sizes in biacromial breadth among all years (η²_p > .62; p < .05), particularly in boys. Similarly, significant improvements in 200-m performance times were observed for both sexes.

Conclusions: The findings of the current investigation might suggest a tendency towards a leaner and more robust morphological profile of elite paddlers in the transition from young to senior categories. In addition, the presence of superior relative body dimensions from young categories seems to be paramount in the evolution to later successful paddling.     

组织工程技术修复骨缺损的研究现状及进展

骨缺损的治疗是困扰骨科临床的难点，传统的治疗方法极为困难。随着组织工程学的迅速发展，通过对种子细胞进行基因修饰、构建复合支架材料及促进组织工程骨早期血管化等方法，使应用组织工程技术治疗骨缺损成为目前研究的热点，作者对其研究现状及进展进行了综述。     

血管组织工程基质材料及管形支架的制备

目的：几种血管基质材料的制作及比较。方法：采用EDC交联胶原和粘多糖材料；采用戊二醛和热交联得到明胶加壳聚糖材料；应用去垢剂，渗透压改变和核酸酶消化的方法，对猪主动脉进行去细胞处理，得到完整的去细胞纤维支架。采用直接模具成型，形成多种管形支架。结果：得到明胶加壳聚糖、完整的猪主动脉去细胞纤维支架等几种基质材料；管形支架外径1cm，内径0．6～0．8cm，放置培养液中10d，可保持管腔形状，不塌陷，不变形。结论：明胶加壳聚糖三维结构好，主动脉脱细胞基质仍显致密，采用模具直接成型、冷冻干燥技术相结合，可以得到多种管状的可降解基质支架。