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81.
Jee‐Wook Lee Myoung‐Ryul Ok Sangmook Lee Jin Ik Lim 《Microscopy research and technique》2015,78(11):982-988
The morphological and quantitative differences between arthritic fibroblast‐like synoviocytes (FLS) and normal FLS were determined as an effective diagnostic tool for rheumatoid arthritis (RA), and confirmed using atomic force microscopy (AFM). Collagen‐induced arthritic (CIA) mice and normal mice were prepared and FLS were isolated by enzymatic digestion from the synovial tissue of sacrificed mice at 5‐week and 8‐week pathogenesis periods. Analysis of cell morphology using AFM revealed that the surface roughness around the nucleus and around the branched cytoplasm was significantly higher in CIA FLS (P < 0.05) than that in normal FLS. In addition, the roughness of two different sites on the arthritic FLS increased with an increase in the duration of pathogenesis. These results strongly suggest that AFM can be widely used as a diagnostic tool in cytopathology to detect the early signs of RA and various others diseases at the intercellular level. Microsc. Res. Tech. 78:982–988, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
82.
Hsin-Wei Huang Chung-May Yang Chang-Hao Yang 《International journal of molecular sciences》2021,22(13)
Diabetic retinopathy (DR) is a common complication of diabetes that causes severe visual impairment globally. The pathogenesis of DR is related to oxidative stress and chronic inflammation. The fibroblast growth factor type 1 (FGF-1) mitogen plays crucial roles in cell function, development, and metabolism. FGF-1 is involved in blood sugar regulation and exerts beneficial antioxidative and anti-inflammatory effects on various organ systems. This study investigated the antioxidative and anti-inflammatory neuroprotective effects of FGF-1 on high-glucose-induced retinal damage. The results revealed that FGF-1 treatment significantly reversed the harmful effects of oxidative stress and inflammatory mediators in retinal tissue in a streptozotocin-induced diabetic rat model. These protective effects were also observed in the in vitro model of retinal ARPE-19 cells exposed to a high-glucose condition. We demonstrated that FGF-1 attenuated p38 mitogen-activated protein kinase and nuclear factor-κB pathway activation under the high-glucose condition. Our results indicated that FGF-1 could effectively prevent retinal injury in diabetes. The findings of this study could be used to develop novel treatments for DR that aim to reduce the cascade of oxidative stress and inflammatory signals in neuroretinal tissue. 相似文献
83.
探讨了牛胎盘中促进成纤维细胞增殖能力的活性成分的制备及其活性验证.采用超滤法从牛胎盘中制备相对分子质量大于10 000的样品,对其进行促进成纤维细胞的增殖实验,证明其具有显著促进细胞增殖能力.离子层析色谱分析可知,此活性成分由 4 个组分组成,分别验证促进成纤维细胞增殖活性,其中组分二、三有显著促进细胞增殖能力. 相似文献
84.
Koyama S 《Journal of Bioscience and Bioengineering》2011,111(5):574-583
The purpose of this study was to develop the modulation methods for the attachment and detachment of specifically positioned adhesive animal cells cultured on an electrode surface with the application of a weak electrical potential. A patterned indium tin oxide (ITO) optically transparent working electrode was placed on the bottom of a chamber slide with a counter-(Pt) and reference (Ag/AgCl) electrode. The ITO patterning was formed by a reticulate ITO region and arrayed square glass regions of varying size. Using the 3-electrode culture system, the author succeeded in modulation of the attachment and detachment of animal cells on the working electrode surface. Animal cells suspended in serum or sera containing medium were drawn to and attached on a reticulate ITO electrode region to which a +0.4-V vs. Ag/AgCl-positive potential was applied. Meanwhile, the cells were successfully placed on the square glass regions by -0.3-V vs. Ag/AgCl-negative potential application. Animal cells were detached not only from the ITO electrode but also from the square glass regions after the application of a ±10-mV vs. Ag/AgCl, 9-MHz [corrected] rectangular wave potential in PBS(-) for 30-60 min. Rectangular wave potential-induced cell detachment is almost completely noncytotoxic, and no statistical differences between trypsinization and the high frequency wave potential application were observed in HeLa cell growth. The electrical modulation of the specifically positioned cell attachment and detachment techniques holds potential for novel optical microscopic cell sorting analysis in lab-on-chip devices. 相似文献
85.
86.
The normal dermal human fibroblastic cell (NDHF) was used to determine a cellular ageing pattern. Cells were cultured in monolayers until the 30th passage. First of all, the following cell growth characteristics were studied: growth rate, fluorimetric DNA determination, DNA repair after UV irradiation. Secondly, metabolism characteristics were examined: lysosomal enzymatic activity and type I and III collagen biosynthesis. Strains were obtained from 10,30,43 and 69-year-old donors to favour a comparison between in vitro and in vivo ageing.
Cell growth ability is modified in vitro only for the oldest strain which shows a significant decrease in the cellular density at the 30th passage. The DNA rate and its repairing ability are not changed by in vitro ageing whatever the strain age.
Lysosomal activity increases during in vitro ageing whereas the collagen I synthesis decreases.
In vitro proliferating potentialities do not reflect in vivo ageing. On the other hand, in this study, metabolic potentialities evolve in the same way in vitro as in vivo and could be a good enough pattern to select anti-ageing products. 相似文献
Cell growth ability is modified in vitro only for the oldest strain which shows a significant decrease in the cellular density at the 30th passage. The DNA rate and its repairing ability are not changed by in vitro ageing whatever the strain age.
Lysosomal activity increases during in vitro ageing whereas the collagen I synthesis decreases.
In vitro proliferating potentialities do not reflect in vivo ageing. On the other hand, in this study, metabolic potentialities evolve in the same way in vitro as in vivo and could be a good enough pattern to select anti-ageing products. 相似文献
87.
Bile acids (BAs) are a group of amphiphilic molecules consisting of a rigid steroid core attached to a hydroxyl group with a varying number, position, and orientation, and a hydrophilic side chain. While BAs act as detergents to solubilize lipophilic nutrients in the small intestine during digestion and absorption, they also act as hormones. Farnesoid X receptor (FXR) is a nuclear receptor that forms a heterodimer with retinoid X receptor α (RXRα), is activated by BAs in the enterohepatic circulation reabsorbed via transporters in the ileum and the colon, and plays a critical role in regulating gene expression involved in cholesterol, BA, and lipid metabolism in the liver. The FXR/RXRα heterodimer also exists in the distal ileum and regulates production of fibroblast growth factor (FGF) 15/FGF19, a hormone traveling via the enterohepatic circulation that activates hepatic FGF receptor 4 (FGFR4)-β-klotho receptor complex and regulates gene expression involved in cholesterol, BA, and lipid metabolism, as well as those regulating cell proliferation. Agonists for FXR and analogs for FGF15/19 are currently recognized as a promising therapeutic target for metabolic syndrome and cholestatic diseases. 相似文献
88.
为了测试富锌酵母提取物促进细胞修复与再生的功效,在体外培育安全给药剂量下测试富锌酵母提取物对成纤维细胞增殖和迁移能力的影响。结果表明,0.078%,0.156%,0.313%,0.625%,1.25%,2.5%的富锌酵母提取物可显著促进成纤维细胞增殖;1%和2%的富锌酵母提取物对成纤维细胞也有明显的促迁移作用。 相似文献
89.
目的观察血脂康对血管紧张素Ⅱ(AngⅡ)诱导的新生大鼠心肌成纤维细胞(CFs)增殖及胶原合成的影响,并探讨可能的分子机制。方法采用胰酶消化法分离培养Sprague-Dawley大鼠心肌成纤维细胞,建立AngⅡ诱导CFs增殖的模型,以MTT比色法和流式细胞仪检测细胞周期分析法观察血脂康对CFs数目和细胞周期的影响。AngⅡ及不同浓度血脂康作用48 h后,用天狼星红染色法检测培养上清中胶原的含量;ELISA法检测细胞培养上清液中TGF-β1蛋白表达;RT-PCR法检测胶原和TGF-β1 mRNA表达。结果AngⅡ对CFs增殖有明显促进作用,血脂康可明显抑制AngⅡ诱导的CFs增殖,且呈剂量依赖性;血脂康可增加G0/G1期细胞百分率,降低S、G2/M期细胞百分率,降低胶原含量、TGF-β1蛋白及胶原和TGF-β1 mRNA的表达。结论血脂康能抑制AngⅡ诱导的CFs增殖和胶原的产生,其作用可能是通过抑制TGF-β1表达实现的。 相似文献
90.
Erik Borg Audrey Frenot Pernilla Walkenström Katrin Gisselfält Christina Gretzer Paul Gatenholm 《应用聚合物科学杂志》2008,108(1):491-497
Artelon® (degradable poly(urethane urea) elastomer) was electrospun into scaffolds for tissue engineering. The diameter of the electrospun fibers, studied by scanning electron microscopy, ranged from 100 nm to a few μm, with an average diameter of 750 nm. The molar mass of the polymer had a major influence on the morphology of the scaffold. Furthermore, aging of the polymer solution caused changes in viscosity, as measured by stress sweeps between 13.5–942 Pa that affected the morphology. The electrospun Artelon mats exhibited about the same elongations to break, both exceeding 200%, measured by tensile tests. The degradation study showed similar degradation behavior in electrospun mats and solids. In vitro study showed that human fibroblasts not only adhere to the surface but also migrate, proliferate, and produce components of an extracellular matrix. These results strongly support the use of electrospun Artelon as a scaffold in tissue engineering. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献