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81.
目的 探讨类风湿关节炎(RA)合并间质性肺病( ILD)患者的临床特点和转化生长因子(TGF)-β1、骨形成蛋白(BMP)-4在血清中的水平.方法 人选28例RA-ILD患者、32例单纯RA患者和20名健康对照,RA-ILD组进一步分为早期组(16例)和中晚期组(12例),酶联免疫吸附试验(ELISA)法测定血清中TGF-β1、BMP-4水平,并分析血清TGF-β1、BMP-4水平与实验室指标的相关性.采用t检验、单因素方差分析及Spearman相关分析法进行数据分析.结果 与单纯RA患者相比,RA-ILD组患者初次发生关节炎时年龄较大,关节功能优于单纯RA组患者,血清类风湿因子(RF)滴度高(P<0.05,P<0.05,P<0.01),出现肺间质病变时间为2~6年,平均(3.0±1.2)年.TGF-β1水平在RA-ILD组稍增高,但3组相比差异无统计学意义(P>0.05).早期RA-ILD组患者TGF-β1血清水平明显增高,与中晚期RA-ILD组及单纯RA组、健康对照组相比较差异均有统计学意义(P<0.01).RA-ILD组患者BMP-4水平低于单纯RA组及健康对照组,差异有统计学意义(P<0.05),且早期RA-ILD组患者BMP-4水平显著下降,与中晚期RA-ILD组及单纯RA组、健康对照组相比较差异均有统计学意义(P<0.05).血清BMP-4水平与TGF-β1水平之间无相关性(P>0.05),血清TGF-β1、BMP-4水平与实验室指标红细胞沉降率、C反应蛋白、RF、抗环瓜氨酸肽(CCP)抗体等均无明显相关性(P均>0.05).结论 在早期RA-ILD患者中血清TGF-β1水平增高,BMP-4水平减低,二者可能参与了RA患者ILD的发生.  相似文献   
82.
目的:研究rhVEGF和rhBMP-7对成骨细胞分化能力的影响.方法:取大鼠颅盖骨组织块,采用改良组织块混合酶消化法培养成骨细胞,将不同浓度的rhVEGF和rhBMP-7加入第四代成骨细胞的培养基继续进行细胞培养,用碱性磷酸酶试剂盒检测定细胞在第1、3、5天的磷酸酶的活性,分析不同浓度的rhVEGF和rhBMP-7对成骨细胞分化的影响.结果:rhVEGF和rhBMP-7能促进成骨细胞的分化,其中,3.125ng/mlrhVEGF和50.000ng/ml rhBMP-7单独或者两者联合作用并于第3天时,对成骨细胞碱性磷酸酶活性的影响最明显.结论:一定剂量的rhVEGF和rhBMP-7可明显促进成骨细胞的分化.  相似文献   
83.
目的使用慢病毒介导兔BMP-2基因转染兔滑膜间充质于细胞(SMSCs),检测其安全性,并在体外定向诱导至软骨细胞。方法通过构建包含BMP-2基因的慢病毒载体,转染SMSCs后行安全性分析;各项检测和MicroRNA分析判断转染后的SMSCs是否进入软骨细胞分化谱系。结果贴块法获得的SMSCs在经分离纯化后,表现出间充质干细胞应有的结构和表面标志物,具有多向分化潜能。增殖动力学、核型分析、致瘤型分析等证实被慢病毒转染的SMSCs安全。Westernblot、免疫荧光等证实且能稳定表达BMP-2蛋白。14d后,免疫组化、MicroRNA检测等证实在不需外加外源性BMP-2的体外环境下SMSCs可自发向软骨细胞分化。结论经重组慢病毒载体感染的兔SMSCs足够安全,能稳定表达BMP-2,体外能自发向软骨细胞分化。  相似文献   
84.
85.
Park J‐C, Kim J.C, Kim B‐K, Cho K‐S, Im G‐I, Kim B‐S, Kim C‐S. Dose‐ and time‐dependent effects of recombinant human bone morphogenetic protein‐2 on the osteogenic and adipogenic potentials of alveolar bone‐derived stromal cells. J Periodont Res 2012; 47: 645–654. © 2012 John Wiley & Sons A/S Background and Objective: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a well‐known growth factor that can induce robust bone formation, and recent studies have shown that rhBMP‐2‐induced osteogenesis is closely related to adipogenesis. The aim of the present study was to determine the dose‐ and time‐dependent effects of rhBMP‐2 on the osteogenic and adipogenic differentiation of human alveolar bone‐derived stromal cells (hABCs) in vivo and in vitro. Material and Methods: hABCs were isolated and cultured, and then transplanted using a carrier treated either with or without rhBMP‐2 (100 μg/mL) into an ectopic subcutaneous mouse model. Comprehensive histologic and histometric analyses were performed after an 8‐wk healing period. To further understand the dose‐dependent (0, 10, 50, 200, 500 and 1000 ng/mL) and time‐dependent (0, 3, 5, 7 and 14 d) effects of rhBMP‐2 on osteogenic and adipogenic differentiation, in vitro osteogenic and adipogenic differentiation of hABCs were evaluated, and the expression of related mRNAs, including those for alkaline phosphatase, osteocalcin, bone sialoprotein, peroxisome‐proliferator‐activated receptor gamma‐2 and lipoprotein lipase, were assessed using quantitative RT‐PCR. Results: rhBMP‐2 significantly promoted the osteogenic and adipogenic differentiation of hABCs in vivo, and gradually increased both the osteogenic and adipogenic potential in a dose‐ and time‐dependent manner with minimal deviation in vitro. The expression of osteogenesis‐ and adipogenesis‐associated mRNAs were concomitantly up‐regulated by rhBMP‐2. Conclusion: The findings of the present study showed that rhBMP‐2 significantly enhanced the adipogenic as well as the osteogenic potential of hABCs in dose‐ and time‐dependent manner. The control of adipogenic differentiation of hABCs should be considered when regenerating the alveolar bone using rhBMP‐2.  相似文献   
86.
目的 探索骨形态发生蛋白7(bone morphogenetic protein 7,BMP7)对2型糖尿病小鼠糖代谢的影响及其机制.方法 将8周龄雄性C57BL/6小鼠,采用小剂量链脲佐菌素注射联合高脂喂养建立2型糖尿病小鼠模型.将建模成功的小鼠分为4组(n=20)∶2型糖尿病模型组,PBS对照组(PBS腹腔注射),BMP7低剂量组(BMP7,100 μg/kg,隔日腹腔注射),BMP7高剂量组(BMP7,200 μg/kg,隔日腹腔注射).4周后,分别检测血糖、血总胆固醇、甘油三酯、血清胰岛素水平、体质量的变化,并计算胰岛素分泌指数HOMA-β和胰岛素抵抗指数HOMA-IR.取小鼠胰腺,Western blot检测蛋白激酶D1(protein kinase D1,PKD1)及磷酸化PKD1的表达变化.结果 与2型糖尿病模型组和PBS对照组相比,BMP7高剂量组和低剂量组的血糖、甘油三酯均明显降低(P<0.05),而血清胰岛素水平、HOMA-β均显著升高(P<0.05).BMP7低剂量组和BMP7高剂量组的体质量均低于对照组(P<0.05),BMP7高剂量组的HOMA-IR低于对照组(P<0.05).Western blot检测发现BMP7处理组的PKD1蛋白表达量与对照组相比差异均无统计学意义(P>0.05),但磷酸化PKD1水平均明显升高(P<0.05).结论 BMP7可以促进2型糖尿病小鼠的胰岛素分泌和改善其胰岛素敏感性,从而降低血糖,其改善胰岛素分泌作用可能与增加PKD1磷酸化有关.  相似文献   
87.
T-cell differentiation is driven by a complex network of signals mainly derived from the thymic epithelium. In this study we demonstrate in the human thymus that cortical epithelial cells produce bone morphogenetic protein 2 (BMP2) and BMP4 and that both thymocytes and thymic epithelium express all the molecular machinery required for a response to these proteins. BMP receptors, BMPRIA and BMPRII, are mainly expressed by cortical thymocytes while BMPRIB is expressed in the majority of the human thymocytes. Some thymic epithelial cells from cortical and medullary areas express BMP receptors, being also cell targets for in vivo BMP2/4 signalling. The treatment with BMP4 of chimeric human-mouse fetal thymic organ cultures seeded with CD34+ human thymic progenitors results in reduced cell recovery and inhibition of the differentiation of human thymocytes from CD4- CD8- to CD4+ CD8+ cell stages. These results support a role for BMP2/4 signalling in human T-cell differentiation.  相似文献   
88.
BACKGROUND: Bone morphogenetic protein-15 (BMP-15) has been shown to influence oocyte maturation and quality. However, no relationship has been established between BMP-15 and oocyte quality/embryonic development in humans. The aim of this study is to investigate BMP-15 level in human follicular fluid (FF) and its possible role in determining oocyte quality and developmental potential. METHODS: A total of 79 oocytes and their corresponding FF from 79 women undergoing ICSI were examined. Individual oocytes were inseminated and subsequently assessed on the basis of their fertilization, cleavage and preimplantation development. BMP-15, FSH, estradiol (E(2)) and progesterone levels of FF were also analysed via the techniques of western blot or radioimmunoassay. RESULTS: Higher FF BMP-15 levels were observed in the fertilized and cleaved groups versus the unfertilized and uncleaved groups, respectively (P < 0.05). The best (Grade I) embryo morphology was associated with higher FF BMP-15 levels than Grade II or III embryos (P < 0.01). A significant positive correlation was found between BMP-15 and E(2) levels in the same follicle. CONCLUSION: The present study demonstrates that the BMP-15 level in FF appears to be a potential factor in predicting oocyte quality and subsequent embryo development, and is correlated with E(2) level, which may additionally be a valuable predictor of oocyte fertilization.  相似文献   
89.
目的探讨肺泡表面活性物质(PS)联合双水平气道正压通气(BiPAP)治疗新生儿呼吸窘迫综合征(NRDS)的临床疗效及对其血清中转化生长因子-β1(TGF-β1)和骨形态发生蛋白-7(BMP-7)表达水平的影响,为临床诊治提供参考依据。方法将2015年1月-2017年4月佳木斯大学附属第一医院收治的80例NRDS患儿随机分为观察组及对照组;对照组采用BiPAP治疗,观察组在对照组治疗的基础上联合PS治疗;在治疗结束后对临床疗效进行评估;治疗前及治疗结束后1h记录患儿呼吸频率、心率、氧合指数指标,并记录不良反应;治疗前及治疗后24h检测患儿血清中TGF-β1及BMP-7水平。结果观察组临床疗效显著优于对照组,差异有统计学意义(P<0.05);治疗后患儿心率、呼吸显著降低,氧合指数显著升高,且观察组患儿心率、呼吸显著低于对照组,氧合指数显著高于对照组,差异有统计学意义(均P<0.05);治疗后两组患儿血清中TGF-β1及BMP-7水平均显著降低,且观察组显著低于对照组,差异有统计学意义(均P<0.05);观察组不良反应发生率显著低于对照组,差异有统计学意义(P<0.05)。结论采用PS联合BiPAP对NRDS患儿治疗后,可有效提高临床疗效并降低不良反应发生率,并可有效改善血清中TGF-β1及BMP-7水平。  相似文献   
90.
OBJECTIVE: To evaluate the effects of various 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) on ectopic osteoinduction by recombinant human bone morphogenetic protein-2 (rhBMP-2) using different administration methods. MATERIALS AND METHODS: Disks containing 5 mug of rhBMP-2 and type I collagen were implanted into the calf muscles of 6-week-old male rats (n = 64). Either the lactone form of simvastatin (SV), open hydroxy-acid form of simvastatin (SVA), cerivastatin (CVA), or vehicle (control) was then administered per orally (PO group) or subcutaneously (SC group) for 20 days. The disks were removed on day 21 after implantation, and ectopic induced bone formation was evaluated by radiographic, histologic, and biochemical analysis. RESULTS: Both the projected and radiopaque area on X-ray film, and the calcium content of the SV group in the SC group (SV-SC group) were significantly greater than those in the other SC and PO groups. Alkaline phosphatase activity and tartrate-resistant acid phosphatase activity in the SV-SC group were significantly lower than those in the other SC and PO groups. Histologic examination revealed an increase of ectopic induced bone volume in the SV-SC group. CONCLUSION: Subcutaneous administration of SV stimulates ectopic osteoinduction by rhBMP-2 through reduction of bone turnover.  相似文献   
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