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《Journal of endodontics》2019,45(7):890-897
IntroductionThe aim was to assess the association of inducible costimulator (ICOS) and ICOS ligand with bone destruction in apical periodontitis (AP).MethodsSpecimens from patients presenting with AP were obtained during apicoectomy and subjected to histopathologic analysis and molecular assessment of ICOS/ICOS ligand. In addition, the experimental AP was induced by exposing the pulp of first mandibular molars of rats. Histologic and radiographic examinations were performed to validate the periapical lesions. The immunolocalization and messenger RNA expression of ICOS/ICOS ligand were evaluated by immunofluorescence staining and quantitative real-time polymerase chain reaction. The osteoclastic activities in periapical lesions, including the lesion size and the expression of tartrate-resistant acid phosphatase and the receptor activator of nuclear factor kappa B ligand, were recorded and followed by correlation analysis with ICOS/ICOS ligand expression.ResultsIn excisional specimens from AP patients, a significantly increased expression of ICOS/ICOS ligand was found compared with the healthy control. In the experimental AP samples, the expression of ICOS/ICOS ligand, tartrate-resistant acid phosphatase, and receptor activator of nuclear factor kappa B ligand was significantly elevated in inflamed periapical tissues (AP group) when compared with the healthy control. The number of ICOS+/ICOS ligand+ cells was highly correlated with the periapical lesion size (r = 0.892, P < .01 and r = 0.930, P < .01, respectively).ConclusionsThe increased expression of ICOS/ICOS ligand in periapical lesions was associated with the inflammatory infiltration and alveolar bone destruction of AP. 相似文献
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目的观察丙丁酚对载脂蛋白E-/-小鼠主动脉粥样硬化斑块形成及主动脉凝集素样氧化型低密度脂蛋白受体1表达的影响,以探讨丙丁酚调节血脂以外的可能的抗动脉粥样硬化作用机制。方法将21只4周龄的雄性载脂蛋白E-/-小鼠随机分成基础饮食对照组、高脂饮食对照组和高脂饮食加丙丁酚组 相似文献
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肠缺血/再灌注致肺损伤时肺内HO-1/CO与iNOS/NO相互作用的研究 总被引:4,自引:1,他引:3
目的观察肠缺血/再灌注(I/R)致肺损伤时肺内HO-1/CO与iNOS/NO的相互作用。方法采用肠缺血/再灌注模型。32只Wistar大鼠随机分为假手术组(Sham组)、肠缺血1 h再灌注6 h组(I/R组)、氨基胍组(AG组)和血晶素组(hemin组)。检测肺组织中HO-1和iNOS的表达,观察肺组织丙二醛(MDA)、血清一氧化氮(NO)及动脉血中氧血红蛋白(Hb-CO)的含量,同时观察肺组织病理形态学改变。结果与Sham组比较,I/R组HO-1和iNOS表达显著增强(均P<0.01);AG组HO-1和iNOS表达较I/R组明显降低(均P<0.05);Hemin组iNOS表达较I/R组明显降低而HO-1表达明显升高(均P<0.05);I/R组肺组织MDA、血清NO、血中HbCO较Sham组显著增加(P<0.05或P<0.01);与I/R组比较,AG组、Hemin组肺组织MDA、血清NO显著降低(P<0.05或P<0.01)。AG组的HbCO明显降低而Hemin组的HbCO明显升高(P<0.05)。病理学检查显示,AG组与Hemin组肺组织损伤程度较I/R组明显减轻。结论NO及CO对肠I/R肺组织具有保护作用,两者之间存在着相互作用,肺内HO-1/CO的大量生成具有使NO产生减少的作用,同时iNOS/NO的过量生成具有上调HO-1表达使CO产生增多的作用。 相似文献
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ZHONG LIANG DENG YI MOU WU YAN HUA ZENG LI LI CHEN MIN JUN YUInstitute of Pathogenic Biology College of Medicine Nanhua University Hengyang P. R. China 《中华微生物学和免疫学杂志(英文版)》2005,3(4):260-265
U.urealyticumisthesmallestprokaryoticorgan ismcapableofself replication.Thetinymicroor ganismcouldbeisolatedfromurogenital,placen tasandtherespiratorytractsofpreterminfants.Moreover,U.urealyticuminfectionmaybein volvedinnon specificurethritis(NSU),prostati tis,postpartumfever,infertility,pelvicinflamma torydisease,neonatalpneumoniaandevenchronic lungdisease(CLD)[1].ItisknownthatU.urealyticumlackscellwallstructureandcontains abundantmembraneproteins,butitspathogenicity isstillunknownclearly.… 相似文献
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Kazuya Takeda Shuhei Sakakibara Kazuo Yamashita Daisuke Motooka Shota Nakamura Marwa Ali El Hussien Jun Katayama Yohei Maeda Masanobu Nakata Shigeyuki Hamada Daron M. Standley Masaki Hayama Takashi Shikina Hidenori Inohara Hitoshi Kikutani 《The Journal of allergy and clinical immunology》2019,143(3):1163-1175.e15
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Chromogranin A (CgA) is associated with microglial activation cascades implicated in neurodegeneration in Alzheimer's, Pick's and Parkinson's diseases. In primary rat microglia, CgA-mediated inducible nitric oxide (iNOS) expression, nitric oxide (NO) production, mitochondrial depolarisation and apoptosis were inhibited by PP2 (Src kinase inhibitor). CgA-mediated iNOS expression and NO production were also inhibited by U0126 (MEK inhibitor), but mitochondrial depolarisation and apoptosis were not. PP2 inhibited ERK phosphorylation; therefore, Src mediates CgA-induced ERK phosphorylation leading to iNOS expression and NO production. Glutamate release induced by CgA was independent of both pathways. These findings provide insights into the way microglia are activated by CgA and the microglial signalling mechanisms associated with neurological disorders such as Alzheimer's disease. 相似文献
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Kang MK Yoon YE Yang JY Kwon KB Park JW Jhee EC 《Mechanisms of ageing and development》2004,125(7):483-490
Cytokines produced by immune cells in pancreatic islets infiltrating are important mediators of beta-cell destruction in insulin-dependent diabetes mellitus. In this study, the effects of retinoic acid (RA) on cytokine-induced beta-cell dysfunction were examined. RA significantly protected interleukin-1 beta (IL-1) and interferon-gamma (IFN-gamma)-mediated cytotoxicity of rat insulinoma cell (RINm5F), and also reduced in IL-1 and IFN-gamma-induced nitric oxide (NO) production, which correlated well with reduced levels of the inducible form of NO synthase (iNOS) mRNA and protein. The molecular mechanism, by which RA inhibited iNOS gene expression, appeared to involve the inhibition of NF-kappa B activation. Our results suggest possible therapeutic value of RA for the prevention of diabetes mellitus progression. 相似文献