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11.
生物活性陶瓷与细胞外基质骨形成对Ca、P、ALP影响 总被引:2,自引:0,他引:2
目的:通过钙(Ca)、磷(P)及碱性磷酸酶(ALP)评价,探讨生物活性陶瓷及细胞外基质与骨细胞相互作用机理,为骨替代材料成骨效应提供依据。方法:选用多种材料进行蒸馏水及血浆接触,体外成骨细胞培养及体内骨诱导试验。采用原子吸收,钼蓝比色及速率法分析化学性能,血浆、细胞冻溶液及组织匀浆中Ca、P、ALP的变化规律。结果:材料组体内、外接触Ca、P、ALP值高于对照组。细胞外基质复合材料组高于相应的非复合材料组。TGF-β1加材料高于BMP复合材料组,而不同材料有所不同,TCP材料高于其它材料。结论:生物活性陶瓷材料均有不同程度的Ca、P离子释放,细胞外基质及Ca、P离子可提高成骨细胞活性,异位骨形成及ALP活性。 相似文献
12.
目的 研究异体细胞外基质材料在疝修补术中的应用效果.方法 采用脱细胞异体真皮基质组织补片对腹股沟疝行无张力修补,观察其临床应用效果.结果 11例患者术后恢复良好,无并发症出现,随访3年均无不良主诉和复发表现.结论 异体细胞外基质材料可作为无张力疝修补术的理想天然生物材料. 相似文献
13.
为探讨前列腺癌(PCa)细胞的转移机制,应用免疫组织化学ABC法在良性前列腺增生(BPH)及PCa组织中对基膜连接蛋白(LN),胶原Ⅳ型蛋白(COLⅣ),纤维连接蛋白(FN)等细胞外基质(ECM)蛋白的表达进行检测,结果BPH组织中基底膜部位LN,COLⅣ及FN的染色呈连续线状分布,PCa组组织基底膜部位LN,COLⅣ及FN的阳性染色呈碎片状或断线状分布。COLⅣ在BPH与PCa组织中的强阳性率无显著性差异(P>0.05)。结果提示ECM在PCa组织中基底膜部位的明显缺失(非连续线状分布)可能是肿瘤转移的重要因素。 相似文献
14.
Amanda M. Cockshutt Laurent Jonet Jean-Claude Jeanny Marc Vigny Dr. Daniel Raulais 《Developmental dynamics》1994,200(3):198-211
Retinoic acid induced heparin-binding protein (RIHB) is a highly basic, soluble polypeptide of the chick embryonic extracellular matrix. We have examined the expression and localization of RIHB during very early embryogenesis by in situ hybridization and immunohistochemistry. RIHB mRNA is very weakly detectable above background in the blastodiscs of unincubated eggs. The expression increases greatly over the first 24 hours of incubation, and is observed throughout the blastodisc in all three of the germ layers following gastrulation. As neurulation occurs, the expression becomes more restricted to certain areas, notably the ectoderm, the neural folds, and especially the notochord. After the neural tube has formed the expression in the tube itself decreases dramatically, whereas the expression in the head ectoderm and the notochord persists. After 72 hours of incubation expression remains relatively high throughout most of the embryo, with higher levels of expression in regions undergoing organogenesis and lower levels in organs which have already differentiated. RIHB protein is also weakly detectable in unincubated eggs as patches of immunoreactive material between the blastodisc and the vitelline. After 6 hours of incubation small regions of basement membrane are immunoreactive. RIHB is detected in this matrix, apparently before even fibronectin. The amount of RIHB protein increases dramatically over the first 24 hours of incubation. It is found in basement membrane separating the epiblast from the hypoblast, then later in that separating the ectoderm from the mesoderm. It is also detected surrounding individual cells, especially of the ectodermal layer. During neurulation RIHB is observed in the basement membrane surrounding the neural fold and the notochord, and in the lamina separating the ectodermal, mesodermal, and endodermal layers. Later in development, RIHB is detected in the basement membrane under the epidermis, throughout the developing limbs, and in the lamina of various developing organs, such as the eye, the pulmonary bud, the intestine, and the mesonephros. These results demonstrate that RIHB is highly expressed during the early embryonic period, by all three germ layers, and is an important and very early component of the embryonic extracellular matrix. Its very broad expression and localization argue for a more general role in development than its demonstrated weak neurotrophic activity. © 1994 Wiley-Liss, Inc. 相似文献
15.
再次液氮冷冻保存对猪主动脉瓣膜细胞活性及组织结构的影响 总被引:1,自引:0,他引:1
目的了解再次冷冻保存对主动脉瓣膜细胞活性及组织结构的影响,探讨液氮冷冻保存的主动脉瓣解冻后再次冷冻保存使用的可行性.方法将猪主动脉瓣叶在抗菌处理后按随机数字表法分成三组,每组6个瓣叶,组Ⅰ作对照,组Ⅱ、组Ⅲ控制降温速率降至-80℃后在液氮中保存,1个月后融化解冻.组Ⅲ解冻并在室温下放置15分钟后更换保存液,再次降温至-80℃后放入液氮中保存,2个月后再融化解冻.采用XTT比色法测定各组瓣膜细胞活性,用免疫荧光组织化学染色、光学显微镜、透射电子显微镜行组织学检测.结果组Ⅱ冷冻保存后瓣膜细胞活性下降到组Ⅰ的63.97%,组织结构一定程度受损;组Ⅲ瓣膜细胞活性下降至组Ⅰ的38.60%,组织结构损害也进一步加重.结论液氮冷冻保存的猪主动脉瓣一经解冻融化,不宜再次冷冻保存使用. 相似文献
16.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl− did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity. 相似文献
17.
We tested the hypothesis that electric perturbation influences 45Ca incorporation in extracellular matrix (ECM) of cartilage in vitro. Hypertrophic chondroblasts of tibial epiphyses (HC), sternum (SC), and skin fibroblasts (F) were cultured from chick embryos. HC, SC, and F cells were micromass seeded three times per week and maintained at 37.5 degrees C with 5% CO2 for two weeks. Cultures were randomly designated control (C) or exposed (E) to a pulsed electromagnetic field (PEMF). A time course experiment of calcium incorporation for all cultured groups showed that 24 h of exposure produced the largest biological response in chondroblasts. Calcium incorporation required supplemental phosphate. Autoradiography data indicated that the calcium incorporation into macromolecules largely occurred in the ECM. 45Ca steady-state perturbation was enhanced by Streptomyces hyaluronidase (SH) but not by testicular hyaluronidase (TH). 45Ca incorporation experiments tested the effects of phosphate, SH, TH, and PEMF alone and in various combinations on these cultures. Only PEMF or SH plus PEMF with phosphate enhanced 45Ca incorporation. Other experiments examined the effect of rotenone or freeze-thawing on cells exposed to PEMF. PEMF plus freeze-thaw enhanced calcium incorporation in HC only. PEMF appeared to cause disruption of the ECM, enhancing the probability of matrix calcification. 相似文献
18.
目的:观察阿托伐他汀对系膜增殖性肾炎(MsPGN)大鼠肾组织细胞外基质(ECM)和纤溶酶原激活剂抑制物-1(PAI-1)表达的影响,探讨其肾脏保护作用的机制。方法:采用抗胸腺细胞血清诱发的MsPGN大鼠模型,将SD大鼠随机分为正常对照组、肾炎模型组、小剂量阿托伐他汀治疗组(8mg·kg^-1·d^-1)和大剂量阿托伐他汀治疗组(16mg·kg^-1·d^-1)。治疗12d后。检测各组大鼠血总胆固醇(CHOL)、甘油三酯(TG)、血肌酐(Scr)和24h尿蛋白,以及肾组织Ⅳ型胶原(Col Ⅳ)、纤维结合蛋白(FN)和PAI-1的表达。结果:阿托伐他汀治疗组大鼠24h尿蛋白、肾组织Col Ⅳ、FN和PAI-1 mRNA的表达明显下降。肾组织病理改变明显改善,与模型组相比有统计学差异(P〈0.05),且呈剂量依赖关系。其中肾炎模型组尿蛋白(30.34±0.62)mg/d。阿托伐他汀小剂量治疗组(21.17±0.79)mg/d,大剂量治疗组(9.77±0.54)mg/d。同时,各组血脂水平无明显差异(P〉0.05)。结论:阿托伐他汀可显著改善MsPGN大鼠肾脏病变,抑制肾组织ECM成分和PAI-1的表达。 相似文献
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