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为了优化岩黄连细胞悬浮培养的条件,研究了在放大培养过程中,岩黄连细胞生长与主要营养成分的代谢动力学,以及生物碱的产生情况。结果表明,在不同培养体系下,细胞生长曲线均呈现"S"型。随着培养体积从50、100 mL放大到500 mL和1 L,培养液中碳源、氮源和磷源的消耗减慢,细胞生物量减少,生物碱产量降低。其中100 mL培养体系所获生物量最高,达到15.2 g/L,生物碱产量也最高,脱氢卡维丁为8.35 mg/mL,小檗碱为4.58 mg/mL。根据本文结果,提出了岩黄连细胞培养条件的优化和大规模细胞培养生产岩黄连生物碱应采取的策略。 相似文献
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黄浩 《中国野生植物资源》2000,19(6):54-56,59
添加活性炭(AC)、抗坏血酸(Vc)、植酸(PA)于红豆杉细胞中进行培养,发现0.1%AC、0.01%PA、高浓度的Vc对红豆杉细胞生长有促进作用,其过氧化物酶活性强,鲜重比大,而多酚氧化酶活性弱,褐变强度小,褐变等级低。 相似文献
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目的:探讨P物质(SP)作用于大鼠腺垂体培养细胞SP受体(SPR)后是否影响第二信使cAMP的水平。方法:应用RIT法测定细胞内cAMP的含量。结果与结论:SP兴奋腺垂体细胞SPR后的生物学反映至少部分是通过刺激第二信使cAMP的生成来完成的。 相似文献
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细胞外基质对体外培养心肌细胞铺展作用的影响 总被引:2,自引:0,他引:2
本研究用分离的新生大鼠心肌细胞,观察不同的细胞外基质,在培养不同时间对心肌细胞铺展的影响。结果表明,不同的细胞外基质影响心肌细胞铺展,在培养8小时即出现差别,48小时差异明显,其中FN促进心肌细胞铺展,而FN的片段延缓心肌细胞的铺展。 相似文献
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诱导子对红豆杉培养细胞紫杉醇产量的影响 总被引:3,自引:0,他引:3
利用红豆杉细胞培养技术生产紫杉醇是目前紫杉醇生产的研究热点之一,并已取得了较大进展,其中如何提高紫杉醇的产量是研究的关键。目前通过促进紫杉醇代谢来提高产量最常用、最重要的方法之一是添加诱导子。这是来源于病原微生物的一类化学物质,具有诱导植物细胞中防卫基因表达诱发植物过敏反应和促进植物细胞中特定次生代谢产物的合成等多种功能。就近年来在红豆杉细胞培养生产紫杉醇方面的研究进展进行简要论述,着重介绍了添加诱导子在促进紫杉醇生物合成中的应用。 相似文献
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本文研究了鸡巯基蛋白酶抑制肽C二型——CPIc-Ⅱ对NC3 H10,TC3 H10,2BS,SHR,WKY和乳鼠心肌细胞的生长的影响,发现CPIc-Ⅱ对所有研究过的细胞都有促生长作用,无一例外。促进作用表现为三方面:(1)促进细胞总蛋白量增加;(2)促进DNA合成:(3)促进细胞数增加。并且转化细胞均比相应的正常细胞对CPIc-Ⅱ更敏感,至此可以得到初步的结论,CPIc-Ⅱ在细胞代谢调节方面是一个正调节因素。 相似文献
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前体物对红豆杉培养细胞中紫杉醇生物合成的影响 总被引:9,自引:1,他引:9
本文报道了添加7种紫杉醇前体物/调节物后,红豆杉(T.chinensis(Pilger)Rehd)TC158细胞系的反应,在红豆杉细胞悬浮培养25天时,分别加入不同浓度乙酸钠,苯甲酸钠,L-苯丙氨酸,甘氨酸,丝氨酸、α-蒎烯,松节油。试验结果表明,各前体物对红豆杉细胞生长无明显影响,均不同程度地促进了紫杉醇的合成。 相似文献
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植酸对红豆杉细胞悬浮培养影响作用的研究 总被引:4,自引:0,他引:4
针对红豆杉细胞培养中经常遇到的褐变问题,以植酸做抗氧化剂,添加到悬浮细胞培养基中,能提高细胞鲜重,明显抑制细胞多酚氧化酶和过氧化物酶活性,从而有效地控制细胞褐变,促进红豆杉悬浮细胞生长。以005%浓度的添加效果最好。 相似文献
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Stem cells are found in naturally occurring 3D microenvironments in vivo, which are often referred to as the stem cell niche. Culturing stem cells inside of 3D biomaterial scaffolds provides a way to accurately mimic these microenvironments, providing an advantage over traditional 2D culture methods using polystyrene as well as a method for engineering replacement tissues. While 2D tissue culture polystrene has been used for the majority of cell culture experiments, 3D biomaterial scaffolds can more closely replicate the microenvironments found in vivo by enabling more accurate establishment of cell polarity in the environment and possessing biochemical and mechanical properties similar to soft tissue. A variety of naturally derived and synthetic biomaterial scaffolds have been investigated as 3D environments for supporting stem cell growth. While synthetic scaffolds can be synthesized to have a greater range of mechanical and chemical properties and often have greater reproducibility, natural biomaterials are often composed of proteins and polysaccharides found in the extracelluar matrix and as a result contain binding sites for cell adhesion and readily support cell culture. Fibrin scaffolds, produced by polymerizing the protein fibrinogen obtained from plasma, have been widely investigated for a variety of tissue engineering applications both in vitro and in vivo. Such scaffolds can be modified using a variety of methods to incorporate controlled release systems for delivering therapeutic factors. Previous work has shown that such scaffolds can be used to successfully culture embryonic stem cells and this scaffold-based culture system can be used to screen the effects of various growth factors on the differentiation of the stem cells seeded inside. This protocol details the process of polymerizing fibrin scaffolds from fibrinogen solutions using the enzymatic activity of thrombin. The process takes 2 days to complete, including an overnight dialysis step for the fibrinogen solution to remove citrates that inhibit polymerization. These detailed methods rely on fibrinogen concentrations determined to be optimal for embryonic and induced pluripotent stem cell culture. Other groups have further investigated fibrin scaffolds for a wide range of cell types and applications - demonstrating the versatility of this approach. 相似文献
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Methods for culturing mammalian cells ex vivo are increasingly needed to study cell and tissue physiology and to grow replacement tissue for regenerative medicine. Two‐dimensional culture has been the paradigm for typical in vitro cell culture; however, it has been demonstrated that cells behave more natively when cultured in three‐dimensional environments. Permissive, synthetic hydrogels and promoting, natural hydrogels have become popular as three‐dimensional cell culture platforms; yet, both of these systems possess limitations. In this perspective, we discuss the use of both synthetic and natural hydrogels as scaffolds for three‐dimensional cell culture as well as synthetic hydrogels that incorporate sophisticated biochemical and mechanical cues as mimics of the native extracellular matrix. Ultimately, advances in synthetic–biologic hydrogel hybrids are needed to provide robust platforms for investigating cell physiology and fabricating tissue outside of the organism. Biotechnol. Bioeng. 2009;103: 655–663. © 2009 Wiley Periodicals, Inc. 相似文献
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A microfluidic platform to satisfy both 3D cell culture and cell-based assay is required for credible assay results and improved assay concept in drug discovery. In this article, we demonstrate a microvalve-assisted patterning (MAP) platform to provide a new method for investigating cellular dynamics by generating a linear concentration gradient of a drug as well as to realize 3D cell culture in a microenvironment. The MAP platform was fabricated by multilayer soft lithography and several microvalves made it possible to pattern a cell-matrix (scaffold) and to exchange media solutions without breaking cell-matrix structure in a microchannel. This approach provides not only exact fluids control, bubble removal, and stable solution exchange in a microchannel, but also reliable scaffold fabrication and 3D cell culture. In this study, hepatotoxicity tests with human hepatocellular liver carcinoma cells (HepG2) were also performed in real-time monitoring where cell morphologies exposed to different drug concentrations were observed at a time. Compared to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, the MAP platform could be used to reduce drug amount and assay time for cell-based assays as much as 10 and 3 times, respectively. 相似文献
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Sun T Norton D McKean RJ Haycock JW Ryan AJ MacNeil S 《Biotechnology and bioengineering》2007,97(5):1318-1328
There are many variables to be considered in studying how cells interact with 3D scaffolds used in tissue engineering. In this study we investigated the influence of the fiber diameter and interfiber spaces of 3D electrospun fiber scaffolds on the behavior of human dermal fibroblasts. Fibers of two dissimilar model materials, polystyrene and poly-L-lactic acid, with a broad range of diameters were constructed in a specifically developed 3D cell culture system. When fibroblasts were introduced to freestanding fibers, and encouraged to "walk the plank," a minimum fiber diameter of 10 microm was observed for cell adhesion and migration, irrespective of fiber material chemistry. A distance between fibers of up to 200 microm was also observed to be the maximum gap that could be bridged by cell aggregates--a behavior not seen in conventional 2D culture. This approach has identified some basic micro-architectural parameters for electrospun scaffold design and some key differences in fibroblast growth in 3D. We suggest the findings will be of value for optimizing the integration of cells in these scaffolds for skin tissue engineering. 相似文献
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Theoretical analysis of insulin-dependent glucose uptake heterogeneity in 3D bioreactor cell culture
Three-dimensional (3D) cell cultures in bioreactors are becoming relevant as models for biological and physiological in vitro studies. In such systems, mathematical models can assist the experiment design that links the macroscopic properties to single-cell responses. We investigated the relationship between biochemical stimuli and cell response within a 3D cell culture in scaffold with heterogeneous porosity. Specifically, we studied the effect of insulin on the local glucose metabolism as a function of 3D pore size distribution. The multiscale mathematical model combines the mass transport within a 3D scaffold and a signaling pathways model. It considers the scaffold heterogeneity, and it describes spatiotemporal concentration of metabolites, biochemical stimuli, and cell density. The signaling model was integrated into this model, linking the local insulin concentration at cell membrane to the glucose uptake rate through glucose transporter type 4 (GLUT4) translocation from the cytosol to the cell membrane. The integrated model determines the cell response heterogeneities in a single channel, hence the biological response distribution in a 3D system. It also provides macroscopic outcomes to evaluate the feasibility of an experimental measurement of the system response. From our analysis, it became apparent that the flow rate is the most important operative variable, and that an optimum value ensures a fast and detectable cell response. This model on insulin-dependent glucose consumption rate offers insight into the cell metabolism physiology, which is a fundamental requirement for the study metabolic disorder such as Type 2 diabetes mellitus, in which the physiological insulin-dependent glucose metabolism is impaired. 相似文献
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As cell culture medium development efforts have progressed towards leaner, serum-free, and chemically defined formulations, it has become increasingly important to ensure that the appropriate concentrations of all nutrients are maintained and delivered at point of use. In light of concurrent efforts to progress to disposable polymeric storage and culture platforms, the characterization and control of medium component interactions with container surfaces can be a key issue in ensuring consistent delivery of these medium formulations. These studies characterize the interactions of lipids with culture surfaces typically encountered in the bioprocess industry using model systems. The extent and kinetics of lipid association with polymeric surfaces were determined using radio-labeled linoleic acid and cholesterol. The effect of methyl-beta-cyclodextrin, a component commonly used to solubilize lipids in culture media, on association kinetics was also examined. In addition, loss of lipids across a sterilizing membrane filter was quantified. We find that there is potential for significant loss of hydrophobic components due to non-specific binding to surfaces at timescales relevant to a typical cell culture process. The extent of loss is dependent on the nature of the hydrophobic component as well as the type of surface. These studies highlight the potential of the extracellular environment to modify medium composition and also emphasize the importance of medium formulation strategies, including those used in the delivery of hydrophobic components. It is noted, however, that the level of loss is very dependent on the specific system including the composition of the culture medium used. 相似文献
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Sorel E. De León Aleta Pupovac Sally L. McArthur 《Biotechnology and bioengineering》2020,117(4):1230-1240
Three-dimensional (3D) cell culture has developed rapidly over the past 5–10 years with the goal of better replicating human physiology and tissue complexity in the laboratory. Quantifying cellular responses is fundamental in understanding how cells and tissues respond during their growth cycle and in response to external stimuli. There is a need to develop and validate tools that can give insight into cell number, viability, and distribution in real-time, nondestructively and without the use of stains or other labelling processes. Impedance spectroscopy can address all of these challenges and is currently used both commercially and in academic laboratories to measure cellular processes in 2D cell culture systems. However, its use in 3D cultures is not straight forward due to the complexity of the electrical circuit model of 3D tissues. In addition, there are challenges in the design and integration of electrodes within 3D cell culture systems. Researchers have used a range of strategies to implement impedance spectroscopy in 3D systems. This review examines electrode design, integration, and outcomes of a range of impedance spectroscopy studies and multiparametric systems relevant to 3D cell cultures. While these systems provide whole culture data, impedance tomography approaches have shown how this technique can be used to achieve spatial resolution. This review demonstrates how impedance spectroscopy and tomography can be used to provide real-time sensing in 3D cell cultures, but challenges remain in integrating electrodes without affecting cell culture functionality. If these challenges can be addressed and more realistic electrical models for 3D tissues developed, the implementation of impedance-based systems will be able to provide real-time, quantitative tracking of 3D cell culture systems. 相似文献
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杜仲细胞悬浮培养生产桃叶珊瑚甙的研究 总被引:1,自引:1,他引:1
对杜仲细胞悬浮培养及其次生代谢产物桃叶珊瑚甙的产生进行了研究,考察了各种理化因子对细胞生长及桃叶珊瑚甙产生的影响。结果表明,在悬浮培养生产桃叶珊瑚甙中,第18天桃叶珊瑚甙的含量达到最大值,培养基为MS、pH为5.8时有利于桃叶珊瑚甙的合成,此时含量高达40.56mg/L。2.0mg/L的2,4-D、NAA及浓度低于1.0mg/L的6-BA均能促使桃叶珊瑚甙的合成,但KT却抑制桃叶珊瑚甙的合成。 相似文献