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目的:探讨体外培养的破骨细胞在自制牛股骨磨片和细胞爬片中扫描电镜制备方法。方法:实验分两组,一组采用新鲜牛股骨制备成5mm×5mm大小的薄片,作为共培养之需;另一组,采用盖玻片制成5mm×5mm的细胞爬片。分别以5×104种植于骨磨片和爬片,培养5天后进行扫描电镜的制备并观察。结果:破骨细胞在牛骨磨片表面生长良好,充分伸展,有细胞突起伸入到实验组材料深部,并形成骨陷窝;在爬片表面生长的破骨细胞,细胞生长良好,粘附性强,细胞之间相互连接较紧密,细胞表面突起明显。结论:牛股骨磨片与破骨细胞在体外相容良好,材料有利于破骨细胞的生长及细胞功能的表达,而破骨细胞爬片更适于细胞外形的观察。将两种方法结合既能反映破骨细胞的形态结构又能展示其破骨功能。 相似文献
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目的:探讨体外培养的破骨细胞在自制牛股骨磨片和细胞爬片中扫描电镜制备方法。方法:实验分两组,一组采用新鲜牛股骨制备成5mm×5mm大小的薄片,作为共培养之需;另一组,采用盖玻片制成5mm×5mm的细胞爬片。分别以5×104种植于骨磨片和爬片,培养5天后进行扫描电镜的制备并观察。结果:破骨细胞在牛骨磨片表面生长良好,充分伸展,有细胞突起伸入到实验组材料深部,并形成骨陷窝;在爬片表面生长的破骨细胞,细胞生长良好,粘附性强,细胞之间相互连接较紧密,细胞表面突起明显。结论:牛股骨磨片与破骨细胞在体外相容良好,材料有利于破骨细胞的生长及细胞功能的表达,而破骨细胞爬片更适于细胞外形的观察。将两种方法结合既能反映破骨细胞的形态结构又能展示其破骨功能。 相似文献
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天然细胞外基质和生物体软组织固有的黏弹性是调控细胞行为和组织修复与再生过程的关键因素.基于动态建构化学反应交联得到的动态高分子水凝胶材料可有效模拟在体细胞或组织的黏弹性力学微环境,为体外调控细胞命运、揭示其力学生物学响应机制提供了重要工具,也为组织修复与再生提供了仿生支架材料.本综述在介绍天然细胞外基质及生物体软组织黏弹性的基础上,重点对仿生黏弹性水凝胶材料的设计思路、性能表征及影响因素等进行了概括和总结,并揭示了黏弹性水凝胶调控细胞、组织行为的规律及机制,最后,分析了目前该领域研究中所存在的问题并对未来发展方向进行了展望.本综述将有助于启发高分子水凝胶的仿生功能化设计思路及材料生物学效应研究,进一步拓展高分子水凝胶材料的生物医学应用. 相似文献
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基于骨陷窝和骨小管的生理结构特性,并考虑到它们内部骨细胞的存在,研究了它们内部组织液的流动。得到了它们内部压力与流量的关系式,为进一步研究密质骨内力敏(mechanosensory)问题提供了依据。 相似文献
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细胞微环境是一个多因素组成的、时空可变的复杂集合,对细胞的行为和功能发挥起着决定性作用。但传统的细胞生物学研究方法很难在体外为细胞提供这样一个复杂的、微尺度的生长环境,致使许多体外研究结果与在体情况相差甚远。近年来,微流控技术与细胞培养技术的结合为细胞微环境的模拟和控制提供了可能。文章通过提炼微环境的重要参数及其特征,介绍微流控技术是如何满足这些参数的需求,探讨了微流控技术在体外模拟细胞微环境的可行性,并总结了近年来该技术在微环境体外模拟研究中取得的成果,对微流控技术在细胞微环境构建中的发展方向和应用前景进行了展望。 相似文献
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细胞微环境与细胞的相互作用日益成为细胞生物学领域研究热点。微环境中物理信号(如基底的力学性能、形貌和牵张力)在控制细胞命运中的作用更不容忽视。其中力学刺激常以不均一的梯度形式参与调节发育、炎症、伤口愈合以及癌症过程中不同细胞的增殖、迁移和分化等行为。水凝胶是模拟细胞外基质(extracellular matrix, ECM)二维/三维组织支架的理想材料。先进的微纳制造技术已被广泛应用于支撑或包裹细胞的仿生水凝胶的合成和微环境的个性化定制研究中。本文阐述了体内细胞力学微环境中刚度和拉压应力刺激的构建方法与表征手段的研究现状,并着重综述了近年来水凝胶在细胞梯度力学微环境体外构建中的应用研究,同时也对未来研究中所面临的挑战提出了新的展望。这些工作对于组织工程及再生医学具有重要意义。 相似文献
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心肌细胞是心脏结构和功能的基本单位,约占心脏细胞总数的三分之一,是心脏发育、生理病理研究的重点对象,然而传统的在体和体外研究技术存在诸多困难,无法实现细胞微环境的有效控制和生理功能的实时动态监测,制约着心肌细胞功能研究的快速发展。近年来迅速发展的微加工技术,尤其是微流控芯片技术为心肌细胞功能研究提供了便利。微流控芯片技术具有微米尺度的细胞及其微环境的时空控制功能,有效提高了体外细胞研究的组织相关性,是心肌细胞生理功能和力学特性研究的重要工具,如实时监测单个心肌细胞的代谢活性、表征细胞的电生理特性和力学特性、研究细胞微环境和力学微环境对心肌细胞形态和功能的影响。本文从前述几个方面对微流控芯片在心肌细胞生理功能研究中的应用进行综述和对其应用前景进行了展望。 相似文献
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肿瘤微环境是决定肿瘤细胞行为的主要影响因素,有别于正常细胞与其周围组织所形成的微环境,组织缺氧和酸中毒、间质高压形成、大量生长因子和蛋白水解酶的产生及免疫炎性反应等构成了肿瘤组织代谢环境的生物学特征,这种特性在肿瘤的发生、进展、转移中扮演重要的角色。胃癌早期症状不典型、转移迅速、死亡率高,是消化系统最常见的恶性肿瘤,目前,关于肿瘤微环境的研究尚处于起步阶段,对胃癌肿瘤微环境的研究有助于我们进一步认识胃癌发生发展的机制,并为临床诊断、治疗胃癌提供依据。因此,本文就近年来在胃癌肿瘤微环境方面的研究进展作一综述。 相似文献
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Pieter H. Anborgh Jennifer C. Mutrie Alan B. Tuck Ann F. Chambers 《Journal of cellular and molecular medicine》2010,14(8):2037-2044
Osteopontin (OPN) is a secreted protein present in bodily fluids and tissues. It is subject to multiple post‐translational modifications, including phosphorylation, glycosylation, proteolytic cleavage and crosslinking by transglutamination. Binding of OPN to integrin and CD44 receptors regulates signalling cascades that affect processes such as adhesion, migration, invasion, chemotaxis and cell survival. A variety of cells and tissues express OPN, including bone, vasculature, kidney, inflammatory cells and numerous secretory epithelia. Normal physiological roles include regulation of immune functions, vascular remodelling, wound repair and developmental processes. OPN also is expressed in many cancers, and elevated levels in patients’ tumour tissue and blood are associated with poor prognosis. Tumour growth is regulated by interactions between tumour cells and their tissue microenvironment. Within a tumour mass, OPN can be expressed by both tumour cells and cellular components of the tumour microenvironment, and both tumour and normal cells may have receptors able to bind to OPN. OPN can also be found as a component of the extracellular matrix. The functional roles of OPN in a tumour are thus complex, with OPN secreted by both tumour cells and cells in the tumour microenvironment, both of which can in turn respond to OPN. Much remains to be learned about the cross‐talk between normal and tumour cells within a tumour, and the role of multiple forms of OPN in these interactions. Understanding OPN‐mediated interactions within a tumour will be important for the development of therapeutic strategies to target OPN. 相似文献
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Ya Qi Cheng Shou Bi Wang Jia Hui Liu Lin Jin Ying Liu Chao Yang Li Ya Ru Su Yu Run Liu Xuan Sang Qi Wan Chang Liu Liu Yang Zhi Chong Wang 《Cell proliferation》2020,53(8)
The tumour microenvironment (TME) plays a pivotal role in tumour fate determination. The TME acts together with the genetic material of tumour cells to determine their initiation, metastasis and drug resistance. Stromal cells in the TME promote the growth and metastasis of tumour cells by secreting soluble molecules or exosomes. The abnormal microenvironment reduces immune surveillance and tumour killing. The TME causes low anti‐tumour drug penetration and reactivity and high drug resistance. Tumour angiogenesis and microenvironmental hypoxia limit the drug concentration within the TME and enhance the stemness of tumour cells. Therefore, modifying the TME to effectively attack tumour cells could represent a comprehensive and effective anti‐tumour strategy. Normal cells, such as stem cells and immune cells, can penetrate and disrupt the abnormal TME. Reconstruction of the TME with healthy cells is an exciting new direction for tumour treatment. We will elaborate on the mechanism of the TME to support tumours and the current cell therapies for targeting tumours and the TME—such as immune cell therapies, haematopoietic stem cell (HSC) transplantation therapies, mesenchymal stem cell (MSC) transfer and embryonic stem cell‐based microenvironment therapies—to provide novel ideas for producing breakthroughs in tumour therapy strategies. 相似文献
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Derubeis AR Mastrogiacomo M Cancedda R Quarto R 《European journal of cell biology》2003,82(4):175-181
Evidence is mounting that an increasing number of cell populations in the adult organism already committed and/or differentiated retain the ability to reprogram themselves and give rise to a different phenotype. Bone marrow stromal cells have long been recognized as early progenitor cells for osteoblasts, chondrocytes, hematopoietic-supportive fibroblasts and adipocytes. Recent reports though have demonstrated a potential of cell populations outside the bone marrow environment to sustain bone formation under specific circumstances. The formation of bone nodules in the spleen of IL-5 transgenic mice has been recently reported (Macias et al. (2001): J. Clin. Invest. 107, 949 - 959). We thus postulated that a cell population exists in the spleen that under particular microenvironmental conditions is able to reprogram itself and pursue a fate other than the tissue-specific one. Therefore we isolated and expanded in vitro spleen-derived stromal cells. After expansion, these cells were challenged with culture conditions designed to induce osteogenic differentiation. We hypothesized that the combination of a proliferating factor (fibroblast growth factor 2) and a differentiating hormone (dexamethasone) would allow us to induce spleen-derived stromal cells to proliferate and at the same time to express osteoblast-specific genes. Thus, spleen-derived stromal cells were isolated from rat spleen and expanded in the presence of fibroblast growth factor 2 and dexamethasone. Once primary cultures reached confluence they were either switched to an osteo-inductive medium or implanted in immunodeficient mice. Although no bone formation was observed in in vivo experiments, in vitro spleen-derived stromal cells were able to deposit a mineralized matrix. Gene expression, as revealed by RT-PCR analysis, evidenced that the deposition of a mineralized matrix was concomitant with the expression of CBFA1 and osteocalcin, along with alkaline phosphatase and bone sialoprotein. Our data suggest that rat spleen-derived stromal cells can undergo osteogenic differentiation in a permissive microenvironment. 相似文献
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酸碱微环境对三种黄瓜主要真菌病原菌的影响 总被引:3,自引:0,他引:3
以引起黄瓜灰霉病(Botrytis cinerea)、黑星病(Cladosporium cucumerium)、霜霉病(Pseudoperonospora cubensis)的3种真菌病害病原菌为代表,通过对病菌栖息微环境酸碱度的调节,达到控制病害的目的。研究看出,黄瓜的3种主要病害病原菌在p H=3.4~10 .4间孢子萌发和致病力表现基本一致:偏酸性环境(p H=4 .2~6 .2 )促进孢子萌发率和致病力增强而偏碱性环境(p H=7.5~10 .4 )则对其明显抑制;降低叶面微环境的酸度,大大减轻了病害的发生、扩展,特别是对黄瓜灰霉病菌的防治有明显效果 相似文献
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N. L. Zakharchenko E. A. Ermakova Yu. F. Zuev 《Russian Journal of Bioorganic Chemistry》2008,34(3):364-368
The hydrolysis reaction of N α-benzoyl-L-arginine ethyl ester catalyzed by trypsin from pig pancreas was comparatively studied in an aqueous buffer solution and in the system of reversed micelles of Aerosol OT in octane (pH 8.5) to determine the mechanisms of influence of the enzyme microenvironment on the rate constants of the elementary stages of the enzymatic reaction. The temperature dependences of the catalytic constant k cat and the rate constant of the second order k cat/K m (s, catalysis efficiency) allowed the determination of the rate constants and the activation energy of elementary stages of the enzymatic reaction. It was revealed that a decrease in the efficiency of catalytic action of trypsin in reverse micelles in comparison with an aqueous solution is first of all determined by a decrease in the rate constant of formation of the enzyme-substrate complex k 1. Possible mechanisms of the effect of the microenvironment on the elementary stages of catalytic action of the enzyme are discussed. 相似文献
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Summary The tremendous diversity in techniques, timing, and facilities used to produce woody plant microcuttings for the nursery industry
can result in substantial differences in the quality and performance of the same clones, depending on the producer. Evidence
suggests that relatively minor procedural discrepancies that occur during the in vitro production stages as a consequence
of these different production methods can determine the survival and acceptability of the plants during subsequent production.
This review tracks the influence of methodologic variables during microshoot proliferation and rooting on quality of the plant,
and examines the continuing repercussions for plant performance in the ex vitro environment.
Presented in the Session-in-Depth Applications of Woody Plant Tissue Culture at the 41st Meeting of the Tissue Culture Association,
Houston, Texas, June 10–13, 1990.
This work was supported by the Illinois Agricultural Experiment Station project no. 65-0363, the Lilly Endowment, the International
Plant Propagator’s Society (Eastern Region), and the Horticultural Research Institute. 相似文献