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81.
目的:探讨哮喘患儿体内嗜酸性粒细胞(eosinophil,EOS)、免疫球蛋白E(IgE)、白介素4(IL-4)及γ干扰素(IFN-γ)水平的检测及临床意义,为临床疾病的诊断和治疗提供依据。方法抽选湖北省鄂州市鄂钢医院2012年11月至2013年6月收治的95例哮喘患儿(哮喘组,其中急性发作期47例、缓解期48例),并抽选同期在本院体检的79例健康患者为对照研究(健康组),采用肺功能仪测定两组的肺功能,并采用痰液诱导、酶联免疫吸附法( ELISA)分别测定患儿痰液中的EOS百分率及血清中IgE、IL-4、IFN-γ水平。结果哮喘组患儿的1秒用力呼气容积(FEV1)/用力肺活量(FVC)的比值(FEV1%)为(69.67±6.63)%,明显低于健康组的(102.27±11.93)%,差异具有统计学意义(t=22.750,P<0.001);哮喘组患儿的FEV1占预计值百分比为(70.45±9.62),明显低于健康组的(90.13±6.34),差异有统计学意义(t=15.582,P<0.001)。哮喘组患儿的痰EOS百分率、血清中IgE、IL-4水平均高于健康组(t值分别为321.962、82.644、76.913,均P<0.05),哮喘组患儿的IFN-γ水平明显低于健康组(t=30.207,P<0.001)。急性发作期哮喘患儿的痰EOS百分率及血清中IgE、IL-4水平均高于缓解期哮喘患儿的(t值分别为15.752、40.762、31.162,均P<0.05),急性发作期哮喘患儿的IFN-γ水平明显低于缓解期哮喘患儿的(t=35.892,P<0.05)。结论血清中IL-4、IgE水平及痰液中EOS百分率升高、血清IFN-γ水平降低,与哮喘的发生、发展密切相关,对其治疗及病情判断具有重要价值。 相似文献
82.
目的:观察反式白藜芦醇( TR)对β-淀粉样肽(Aβ25-35)致痴呆大鼠海马旁回的保护作用。方法先将SD大鼠分为3,20月龄2大组,然后再分为假手术组、模型组、低与高剂量实验组。用Aβ25-35制痴呆模型后,实验组灌胃给TR 10,40 mg? kg-1? d-1,假手术组、模型组均给予0.9%NaCl(1 mL/100 g),连续10 d。用实时定量PCR法检测8组大鼠海马及皮质半胱氨酸蛋白酶-3(caspase-3)、DNA聚合酶γ的表达。结果模型组与假手术组的caspase-3、DNA聚合酶γ表达水平比较差异有统计学意义( P<0.01),说明造模成功。 TR对caspase-3、DNA聚合酶γ表达水平的下调非常显著( P<0.01)。模型组3月龄较20月龄大鼠的caspase-3表达量明显增高( P<0.05)。实验组3月龄与20月龄大鼠caspase-3表达量差别有统计学意义( P<0.05)。结论 TR对损伤的大鼠海马周围皮层神经元有保护作用。 相似文献
83.
ObjectiveThe study was aimed to explore the hepatocellular protective functions of cafestol during hepatic ischemia-reperfusion injury and the possible mechanisms.MethodsNinety male Balb/c mice were randomly divided into seven groups, including normal control group, L-cafestol(20mg/kg) group, H-cafestol(40mg/kg) group, sham group, IR group, L-cafestol(20mg/kg) + IR group, H-cafestol(40mg/kg) + IR group. Serum liver enzymes (ALT, AST), inflammation mediators, proteins associated with apoptosis and autophagy, indicators linked with ERK/PPARγ pathway, and liver histopathology were measured using ELISA, qRT-PCR, immunohistochemical staining, and western blotting at 2, 8, and 24 hours after reperfusion.ResultsOur findings confirmed that cafestol preconditioning groups could reduce the levels of ALT and AST, alleviate liver pathological damage, suppress the release of inflammation mediators, inhibit the production of pro-apoptosis protein including caspase-3, caspase-9 and Bax, decrease the expression of autophagy-linked protein including Beclin-1 and LC3, increase anti-apoptosis protein Bcl-2, and restrain the activation of ERK and PPARγ.ConclusionCafestol preconditioning could attenuate inflammatory response, apoptosis and autophagy on hepatic ischemia reperfusion injury by suppressing ERK/PPARγ pathway. 相似文献
84.
目的 探讨灵芝多糖(GLP)对外周血淋巴细胞免疫分群的影响及其作用机制.方法 取肿瘤患者和正常人的外周血,分离外周血单个核细胞(PBMC)后,用不同剂量的GLP(10 ng/ml、50ng/ml和100 ng/ml)刺激后,用流式细胞仪检测DC细胞表面分子(HLA-DR、CD83和CD11c)、Th1细胞、Th2细胞和NK(CD3-CD56+)细胞数;并进一步用免疫磁珠分选出正常人外周血CD4+ Th细胞后用不同浓度GLP刺激24h后,荧光实时定量Q-PCR检测Th1和Th2细胞因子的表达水平,Westernblot分析Th1分化相关的转录因子水平.结果 灵芝多糖可以在体外呈浓度依赖性增加外周血中Th1细胞亚群和DC共刺激分子的表达(P<0.01),并且增加STAT4的表达和IL-12、IFN-γ和TNF-α的mRNA的表达水平(P<0.01).结论 灵芝多糖可能通过增加Th细胞STAT4的表达水平,促进其向Th1细胞分化,并增加Th1的分泌细胞因子. 相似文献
85.
V. S. Yadav K. P. Mishra D. P. Singh S. Mehrotra Dr. V. K. Singh 《Immunopharmacology and immunotoxicology》2013,35(3):485-497
Curcumin (diferuloylmethane), found in the spice turmeric, exhibits anti-inflammatory, antioxidant, and chemopreventive activities. However, the effect of curcumin on the immunological responses largely remains unknown. In this study we have investigated the effect of curcumin on mitogen (phytohaemagglutinin; PHA) stimulated T-cell proliferation, natural killer (NK) cell cytotoxicity, production of cytokines by human peripheral blood mononuclear cells (PBMCs), nitric oxide (NO) production in mouse macrophage cells, RAW-264.7. Furthermore, we have carried out an electromobility shift assay to elucidate the mechanism of action of curcumin at DNA protein interaction level. We observed that curcumin inhibits PHA-induced T-cell proliferation, interleukin-2 production, NO generation, and lipopolysachharide-induced nuclear factor-κB (NF-κB) and augments NK cell cytotoxicity. Our results suggest that curcumin most likely inhibits cell proliferation and cytokine production by inhibiting NF-κB target genes involved in the induction of these immune parameters. 相似文献
86.
Mariabeatrice Principi Richard Day Stefania Marangi Osvaldo Burattini Vincenzo De Francesco Marcello Ingrosso 《Immunopharmacology and immunotoxicology》2013,35(2):185-195
Tumor necrosis factor alpha (TNFα) in intestinal mucosa plays a key role in the inflammation characterizing Crohn’s disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFα and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFα and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFα and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFα in CD. In conclusion, TNFα and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFα. 相似文献
87.
Moisés Armides Franco-Molina Yareellys Ramos-Zayas Erika Evangelina Coronado-Cerda Edgar Mendoza-Gamboa Pablo Zapata-Benavides Silvia Elena Santana-Krymskaya 《Immunopharmacology and immunotoxicology》2013,35(5):437-443
AbstractObjective: The aim of the present study was to evaluate the therapeutic potential of autologous DCs loaded with whole tumor cell lysate of CTVT generated under a simplified and rapid procedure in vitro production process, in a vulvar submucosal model of CTVT in dogs.Materials and methods: We generated a model of intravulvar CTVT in dogs. A CTVT lysate antigen was prepared according to the method of 1-butanol and after administered with complete Freund's adjuvant via subcutaneous in female healthy dogs and challenge with CTVT cells to corroborate the immunogenicity. Short-time generated dendritic cell pulsed with CTVT whole-lysate was performed, and analyzed by FITC-dextran uptake assay and characterized using anti-canine monoclonal antibodies CD14, CD80, CD83, and DLAII by flow cytometry. Dendritic cell therapy was administered in a frequency of three times every 2 weeks when the CTVT had 4 months of growth and 89?±?5 cm diameter. The CD3+, CD4+ and CD8+ lymphocytes were determined by flow cytometry, and IFN-γ by ELISA assay.Results and discussion: The administration of CTVT whole-lysate resulted in tumor prevention. The short-time generated dendritic cell pulsed with CTVT whole-lysate administration resulted in an efficient reduction and elimination of CTVT, probably due to the increase in lymphocyte populations (CD3+, CD4+, and CD8+), IFN-γ production and tumor infiltrating lymphocytes.Conclusion: In conclusion, this study demonstrates the efficacy of immunotherapy based in short-time generated dendritic cell pulsed with CTVT whole-lysate for the treatment of CTVT, and offer veterinary oncologists new alternative therapies to treat this and another malignancy. 相似文献
88.
Yan Li Yuan-Yi Zhang Li-Teng Yang Jiang-Qi Liu Chuan Zhou Zhi-Qiang Liu Gui Yang Li-Hua Mo Zhi-Gang Liu Bai-Sui Feng Ping-Chang Yang 《European journal of immunology》2021,51(2):459-470
Ulcerative colitis (UC) is a disease that frequently relapses and affects more than 0.1% general population; the underlying mechanism is poorly understood. Published data show that polymorphonuclear neutrophils (PMN) contribute to the pathogenesis of UC. This study aims to identify antigen (Ag)-specific PMNs and investigate their role in UC relapse. In this study, the correlation between PMN activities and UC relapse was assessed in a group of UC patients. A UC mouse model was developed to expand the findings of UC patient study. The results showed that a positive correlation was detected between the high PMN activities and the food Ag-specific IgG amounts in colon biopsies of UC patients. UC patient-derived Ag-specific PMNs could be activated upon exposure to food specific Ag. The Ag/FcγRI complexes were detected on the surface of PMNs in UC patients. Re-exposure of sensitized PMNs to specific Ag triggered PMN activation and induced UC-like inflammation in the mouse colon. We conclude that FcγRI plays a critical role in UC relapse. Inhibition of FcγRI can efficiently inhibits experimental UC. 相似文献
89.