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961.
962.
CD146 as a new marker for an increased chondroprogenitor cell sub‐population in the later stages of osteoarthritis
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Xinlin Su Wei Zuo Zhihong Wu Jun Chen Nan Wu Pei Ma Zenan Xia Chao Jiang Zixing Ye Sen Liu Jiaqi Liu Guangqian Zhou Chao Wan Guixing Qiu 《Journal of orthopaedic research》2015,33(1):84-91
Cartilage‐derived mesenchymal stem cells (MSCs) have been isolated with different methods. In this study lateral and medial femoral condyles were respectively collected from patients with late‐stage osteoarthritis during the total knee arthroplasty. After digestion of the cartilage tissues with type II collagenase and analysis by fluorescence‐activated cell sorting (FACS) with CD146, a chondroprogenitor cell sub‐population were isolated and purified. The expression of other MSC‐associated markers in the CD146+ chondroprogenitors was analyzed by flow cytometry. Multi‐lineage differentiation capacity of CD146+ chondroprogenitors was compared with that of unsorted chondrocytes and adipose‐derived MSCs (ADMSCs). Higher percentage of CD146+ chondroprogenitors isolated from the medial femoral condyles was observed than that from the lateral. CD146+ chondroprogenitors expressed high levels of MSC‐specific surface antigens, and showed higher chondrogenesis capacity than ADMSCs and unsorted chondrocytes in a 3D cell pellet culture model. Thus CD146 might be a new cell surface marker for cartilage progenitor cell population in the late‐stage osteoarthritis. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:84–91, 2015. 相似文献
963.
964.
The derived relational repertoire of a teenager with autism spectrum disorder was tested in two slightly different contexts using a multiple treatments reversal design. Both contexts involved match-to-sample training and testing with abstract stimuli, but one involved referring to the stimuli as the names and sounds of “animals.” In the latter context, training of baseline relations was more efficient and derivation was shown to be more likely. This demonstrates the importance of contextual control over derived relational responding and suggests that the animal context may be a useful one for assessing and training derived relations for individuals in which the derived relational repertoire is not as robustly established across contexts. 相似文献
965.
利用全细胞膜片钳技术,观察不同浓度地塞米松急性灌洗大鼠肾上腺嗜铬细胞(AMCC)后钙通道电流和烟碱受体通道电流(INIC)的变化,地塞米松对大鼠AMCC的急性作用为明显抑制INIC而对电刺激所诱发的钙通道电流无明显影响,提示糖皮质激素对大鼠AMCC分泌儿茶酚胺的急性效应可能与烟碱受体直接相关。 相似文献
966.
阿托伐他汀对不稳定型心绞痛患者树突状细胞功能的影响 总被引:16,自引:0,他引:16
目的 研究不稳定型心绞痛患者(UAP)树突状细胞(DC)的功能及阿托伐他汀对其的影响。方法 将27例UAP分为常规治疗组(12例)和常规加阿托伐他汀治疗组(15例),分别于治疗前及治疗后2周取血分离外周血单个核细胞,在含粒细胞巨噬细胞集落刺激因子和白细胞介素(IL)4的培养条件下制备DC。用流式细胞仪检测DC表面共刺激分子CD86(B7-2)的表达;混合淋巴细胞反应(MLR)检测DC对同种异体T淋巴细胞的刺激能力;ELISA法测定MLR上清液中的细胞因子;探讨CD86表达与冠心病危险因素及C反应蛋白(CRP)的相关性。结果 与正常对照组比较,UAP者DC表面CD86的表达明显增高;对T淋巴细胞刺激的能力增强;经DC刺激的淋巴细胞分泌致炎细胞因子(IL-1β,IL-6,肿瘤坏死因子α)增多,抑炎细胞因子(IL-10)减少;用药前CD86的表达与血LDL-C水平正相关;阿托伐他汀抑制DC功能的同时显著降低血CRP水平;且CD86与CRP水平正相关。结论 (1)UAP者DC的功能亢进,由此启动的T淋巴细胞的增殖和炎性细胞因子分泌可能是UAP者动脉斑块不稳定的原因,(2)LDL-C可能是其刺激因素;(3)阿托伐他汀抑制斑块炎症的机制之一是其对DC的抑制。 相似文献
967.
Bin Cao Xiao-Ping Chen Peng Zhu Lei Ding Jian Guan Zuo-Liang Shi 《World journal of gastroenterology : WJG》2008,14(44):6802-6807
AIM: To evaluate the effects of interferon-α-2b (IFN- α-2b) on expression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in human hepatocellular carcinoma (HCC) inoculated in nude mice and to study the underlying mechanism of IFN-α- 2b against HCC growth. METHODS: Thirb/-two nude mice bearing human HCC were randomly divided into four groups (n = 8). On the 10th day after implantation of HCC cells, the mice in test groups (groups A, B and C) received IFN-α- 2b at a serial dose (10000 IU for group A, 20000 IU for group B, 40000 IU for group C sc daily) for 35 d. The mice in control group received normal saline (NS). The growth conditions of transplanted tumors were observed. Both genes and proteins of COX-2 and VEGF were detected by RT-PCR and Western blot. Apoptosis of tumor cells in nude mice was detected by TUNEL assay after treatment with IFN-α-2b. RESULTS: Tumors were significantly smaller and had a lower weight in the IFN-α-2b treatment groups than those in the control group (P 〈 0.01), and the tumor growth inhibition rate in groups A, B and C was 27.78%, 65.22% and 49.64%, respectively. The expression levels of both genes and proteins of COX-2 and VEGF were much lower in the IFN-α-2b treatment groups than in the control group (P 〈 0.01). The apoptosis index (AI) of tumor cells in the IFN-α-2b treatment groups was markedly higher than that in the control group (P 〈 0.01). Group B had a higher inhibition rate of tumor growth, a lower expression level of COX-2 and VEGF and a higher AI than groups A and C (P 〈 0.05), but there was no significant difference between groups A and C. CONCLUSION: The inhibitory effects of IFN-α-2b on implanted tumor growth and apoptosis may be associated with the down-regulation of COX-2 and VEGF expression. There is a dose-effect relationship. The medium dose of IFN-α-2b for inhibiting tumor growth is 20 000 IU/d. 相似文献
968.
969.
目的研究花生四烯酸细胞色素P450(cytochrome P450,CYP)表氧化酶代谢产物表氧二十碳三烯酸(epoxyeicosatrienoic acid,EET)对牛主动脉内皮细胞(bovine endothelial cells,BAEC)、对血管生成的影响及其机制.方法分离BAEC培养,给予外源性EET刺激、重组腺相关病毒介导的各种CYP表氧化酶(CYP2J2,CYP2C11,CYPF87V)转染后,采用细胞计数、噻唑蓝比色法检测细胞增殖改变,用流式细胞仪检测对细胞增殖周期的影响,同时检测细胞趋化移行的改变,比较对Matrigel中毛细血管样结构形成的影响,观察表氧化酶过度表达对鸡胚尿囊绒毛膜血管生成和大鼠缺血后肢毛细血管生成的影响.结果各种EET刺激或表氧化酶病毒转染均显著促进BAEC的增殖、趋化和移行,并使Matrigel中毛细血管样结构的形成明显增加,且EET呈剂量依赖性效应,而合用一氧化氮合酶抑制剂、丝裂原激活的蛋白激酶(mitogen-activated protein kinase,MAPK)抑制剂或磷脂酰肌醇-3激酶(phosphatidylinositol 3-kinase,PI3K)抑制剂均可显著抑制上述效应,另外表氧化酶病毒转染尚能明显促进CAM小血管和大鼠缺血后肢毛细血管的生成.结论花生四烯酸细胞色素P450(CYP)表氧化酶及其代谢产物EET可显著促进血管的生成,可改善局部组织的缺血,其作用由MAKP和PI3K介导,部分效应由其对一氧化氮的上调作用介导. 相似文献
970.
Zhe Yang Li Mei Fei Xia Qingming Luo Ling Fu Hui Gong 《Biomedical optics express》2015,6(5):1797-1811
In vivo functional imaging at single-neuron resolution is an important approach to visualize biological processes in neuroscience. Light sheet microscopy (LSM) is a cutting edge in vivo imaging technique that provides micron-scale spatial resolution at high frame rate. Due to the scattering and absorption of tissue, however, conventional LSM is inadequate to resolve cells because of the attenuated signal to noise ratio (SNR). Using dual-beam illumination and confocal dual-slit detection, here a dual-slit confocal LSM is demonstrated to obtain the SNR enhanced images with frame rate twice as high as line confocal LSM method. Through theoretical calculations and experiments, the correlation between the slit’s width and SNR was determined to optimize the image quality. In vivo whole brain structural imaging stacks and the functional imaging sequences of single slice were obtained for analysis of calcium activities at single-cell resolution. A two-fold increase in imaging speed of conventional confocal LSM makes it possible to capture the sequence of the neurons’ activities and help reveal the potential functional connections in the whole zebrafish’s brain.OCIS codes: (180.2520) Fluorescence microscopy, (110.0110) Imaging systems, (170.3880) Medical and biological imaging, (170.2945) Illumination design, (180.1790) Confocal microscopy 相似文献