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61.
湖北青砖茶对IBS-D模型大鼠肠道敏感性的影响   总被引:1,自引:0,他引:1  
研究了湖北青砖茶对腹泻型肠易激综合征(IBS-D)模型大鼠肠道的影响。结果表明,与正常组相比,模型组的痛阈值明显降低,血清中炎症因子前列腺素2(PGE2)、肿瘤坏死因子(TNF-α)、类胰蛋白酶的含量明显增加;与模型组比较,湖北青砖茶低剂量组、高剂量组能够显著升高痛阈值,而血清中炎症因子PGE2、TNF-α、类胰蛋白酶的含量显著降低,且具有剂量依赖性。由此表明湖北青砖茶可降低IBS-D模型大鼠的肠道敏感性,其作用机制可能与血清中PGE2、TNF-α和类胰蛋白酶含量的降低有关。  相似文献   
62.
AIM: To investigate the effect of growth hormone receptor (GHR) knockdown on nuclear factor-κB (NF-κB) activity and inflammatory cytokine production stimulated by growth hormone (GH) in 3T3-L1 adipocytes. METHODS: The specific siRNA for GHR was transfected into 3T3-L1 adipocytes to silence GHR expressions. The effects of GH on NF-κB activation and inflammatory cytokine production in 3T3-L1 adipocytes transfected with siRNA-GHR or siRNA-control were measured by dual-luciferase system analysis, real-time RT-PCR and ELISA. RESULTS: The protein expression of GHR was diminished after transfection with GHR specific siRNA. Dual-luciferase reporter system analysis revealed that GHR knockdown resulted in attenuation of GH-stimulated NF-κB activation in the 3T3-L1 adipocytes. GHR knockdown ameliorated the GH-induced production of inflammatory cytokines TNF-α, IL-1β, IL-6, MCP-1 and MIP-1α in the 3T3-L1 adipocytes. CONCLUSION: Knockdown of GHR might be efficacious to prevent GH-induced inflammatory responses in the 3T3-L1 adipocytes.  相似文献   
63.
在建立犊牛原代肝细胞体外培养模型的基础上,通过培养液中添加不同浓度的非酯化脂肪酸(Nonesterifiedfatty acids,NEFAs),运用实时荧光定量PCR和ELISA方法,测定NEFAs对肝细胞中炎性因子TNFα、IL-6和IL-1β的mRNA表达及其活性的影响。结果显示,NEFAs作用肝细胞9h后,与对照组相比,高浓度NEFAs(1.8mmol/L)组肝细胞中TNFα、IL-1β的mRNA表达水平显著增加(P〈0.05),IL-6的mRNA表达水平在2.4retool/L时极显著增加(P〈0.01),低浓度NEFAs(0.6、1.2mmol/L)组肝细胞中TNFα、IL-1β和IL-6的mRNA表达水平无显著差异(P〉0.05);并且TNFα、IL-1G的活性在NEFAs浓度达到1.8、2.4mmol/L显著高于对照组(P〈0.01),且呈剂量依赖性作用,IL-6的活性在在NEFAs浓度达到1.8mmol/L显著高于对照组(P〈0.01),在2.4mmol/L也高于对照组,但差异不显著。结果表明,高浓度NEFAs在-定程度上能引起或加剧奶牛肝细胞炎性反应,可能是导致产后奶牛肝功能炎性损伤主要因素。  相似文献   
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旨在初步探究非洲猪瘟病毒(African swine fever virus,ASFV)多基因家族MGF360-13L基因的功能。使用生物信息学软件对MGF360-13L基因进行分析;构建真核表达质粒pVAX1-MGF360-13L并转染至293T细胞进行表达;利用同源重组方法构建基因缺失毒株ASFV-ΔMGF360-13L,以相同的感染复数(MOI=0.01)在猪肺泡巨噬细胞(PAMs)中感染基因缺失毒株和亲本毒株(ASFV CN/GS/2018)后,利用红细胞吸附试验(HAD)计算病毒滴度并绘制体外生长曲线;以MOI=1将ASFV-ΔMGF360-13L和ASFV CN/GS/2018分别感染猪骨髓巨噬细胞(BMDM),利用qPCR和ELISA测定细胞炎性因子IL-1β、IL-6和TNF-α的表达水平。结果表明,MGF360-13L基因在ASFV基因Ⅱ型中相对保守,编码蛋白属于非分泌型、无跨膜区、亲水性好;构建的真核表达质粒pVAX1-MGF360-13L被293T细胞表达;成功获得MGF360-13L单基因缺失毒株ASFV-ΔMGF360-13L,与ASFV CN/GS/2018相比,其体外复制没有显著性差异;在ASFV-ΔMGF360-13L感染BMDM后,IL-1β、IL-6和TNF-α炎性细胞因子在转录和分泌水平都显著高于ASFV CN/GS/2018。本研究成功制备了ASFV的MGF360-13L基因缺失毒株,并证实了MGF360-13L基因作为ASFV复制非必需基因具有抑制炎性因子表达的功能,这为进一步注释ASFV MGF360-13L基因功能提供了线索。  相似文献   
66.
选用24只3月龄、体质量(13.0±l.0)kg的雄性波尔山羊,随机分为4组,每组6只。试验期为60d。其中Ⅰ组为对照组,饲料添加微量元素;Ⅱ组(低剂量组)、Ⅲ组(中剂量组)、Ⅳ组(高剂量组)分别按0.5、1.0、2.omL/kg肌肉注射“生命元”。试验前1d、试验后15、30、45、60d分别测定波尔山羊的采食量、日增重、血液生理生化指标以及血清IgG、IgM、IgA、IL-2、IL-6的含量。结果表明:(1)试验期0-60d内,与Ⅰ组波尔山羊相比,Ⅲ组能显著(P〈0.05)提高成产性能。(2)60d时,与Ⅰ组相比,Ⅱ组、Ⅲ组和Ⅳ组均能显著(P〈0.05)提高波尔山羊红细胞数和血红蛋白含量。(3)与Ⅰ组相比,“生命元”能明显改善波尔山羊基础代谢水平,提高波尔山羊血糖、总蛋白含量,但Ⅲ组能显著(P〈0.05)降低血清尿素氮含量(45d)、降低总胆固醇含量(60d)。(4)试验组波尔山羊血清IgG、IgM、IgA含量在各个时期内显著或极显著高于对照组(P〈0.05或P〈0.01)。(5)试验组波尔山羊血清中IL-2含量均高于对照组,但差异不显著;试验组在注射后15d血清IL-6含量显著高于对照组。结论:复方微量元素注射液“生命元”能提高波尔山羊生产性能、红细胞数和血红蛋白含量,改善糖、蛋白质和脂肪代谢,并能提高波尔山羊血清中IgG、IgM、IgA及IL-2、IL-6的含量。其中以1.0mL/kg肌肉注射效果最好。  相似文献   
67.
动物黏膜免疫与细胞因子的研究进展   总被引:1,自引:0,他引:1  
黏膜免疫系统是机体抵抗病原微生物的第一道防线,而黏膜相关趋化性细胞因子在生理病理过程中也发挥重要作用,其对研究黏膜免疫系统的特殊功能和独特性质具有重要意义.本文概述了黏膜免疫的特点、机制、途径及与之相关的几类重要的细胞因子.  相似文献   
68.
Persson Waller, K., Colditz, I.G., Flapper, P. and Seow, H.-F., 1997. Leukocyte and cytokine accumulation in the ovine teat and udder during endotoxin-induced inflammation. Veterinary Research Communications, 21 (2), 101-115The accumulation of leukocytes, ovine serum albumin and the cytokines interleukin-1 (IL-1), tumour necrosis factor- (TNF-), interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon- (IFN-) was studied during endotoxin-induced inflammation in lactating and dry ovine udders, and in the teat cisterns of dry ewes after surgical closure of the passage between the teat and udder cisterns. Samples were taken before infusion and hourly up to 10 h after infusion of 0.1, 1 or 10 µg of endotoxin, or infusion of pyrogen-free saline (PFS) as a control. Rectal temperatures were measured.A significant dose- and time-dependent accumulation of leukocytes, mainly neutrophils, was observed in the lactating udders and in the teat cisterns. In the dry udders, the leukocyte accumulation was significant for time but not for dose. Peak numbers of cells were reached at 3-4 h in the dry udders and in the teat cisterns, but not until 10 h after infusion in the lactating udders. The changes in the ovine serum albumin concentrations mostly paralleled changes in leukocyte numbers.A role was indicated for TNF-, IL-8 and GM-CSF, but not for IL-1 and IFN-, during endotoxin-induced inflammation in the ovine udder. Release of TNF-, IL-8 and GM-CSF was most prominent in lactating udders, peaking at 2 or 3 h after infusion, but was also detected in dry udders and teat cisterns. Detectable levels of IL-1 and IFN- were occasionally found in all three groups.  相似文献   
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70.
The purpose of this study was to investigate the effects of recombinant 10 kDa culture filtrate protein (CFP10) of Mycobacterium tuberculosis on the inflammatory responses mediated by Toll-like receptor (TLR) signaling in A549 cells. The recombinant plasmid pCzn1-CFP10 was obtained by amplifying the cfp10 gene fragment using PCR and cloning it into the prokaryotic expression vector pCzn1. The obtained recombinant plasmid pCzn1-CFP10 was transformed into Escherichia coli BL21(DE3) and induced by IPTG to express the recombinant protein CFP10 (rCFP10). The purified rCFP10 protein was preserved after endotoxin was removed and desalted before use. The effect of rCFP10 treatment on the survival rate of A549 cells was detected by MTT assay. A549 cells were treated with rCFP10 to detect changes of key molecules of TLR signaling pathway and downstream inflammatory factors in A549 cells by qRT-PCR,Western blot and ELISA. The results showed that the recombinant expression vector pCzn1-CFP10 was successfully constructed and the high-purity rCFP10 protein was expressed and purified in this study. MTT assay showed that rCFP10 could inhibit the survival rate of A549 cells in a time- and concentration-dependent manner. In addition, rCFP10 could significantly (P<0.05) up-regulate the key molecules of TLR pathways TLR2, TLR4, MyD88, TRAF6, NF-κBp65 and downstream inflammatory cytokines IL-6 and TNF-α in A549 cells as compared to the control group. The recombinant Mycobacterium tuberculosis protein CFP10 could promote the secretion of cytokines by activating TLR receptor signaling pathway in A549 cells, which will provide a theoretical basis for further understanding of the pathogenesis of Mycobacterium tuberculosis.  相似文献   
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