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201.
为明确PYY对巨噬细胞炎性细胞因子分泌的调节作用,本试验分离培养健康小鼠腹腔巨噬细胞,不同浓度PYY预处理后,以LPS刺激。ELISA方法检测细胞培养上清中TNF-α、IL-6含量,半定量PCR方法检测细胞中TNF-α、IL-6mRNA表达变化。结果显示:高浓度的PYY1-36(10-9-10-7 mol/L)和PYY3-36(10-8-10-7 mol/L)对LPS诱导小鼠腹腔巨噬细胞TNF-α分泌具有显著抑制作用(P〈0.05);PYY1-36对LPS诱导小鼠腹腔巨噬细胞IL-6分泌无明显作用(P〉0.05);不同浓度PYY3-36(10-11-10-7 mol/L)对LPS诱导小鼠腹腔巨噬细胞IL-6分泌均具有显著抑制作用(P〈0.05)。表明PYY对LPS诱导小鼠腹腔巨噬细胞炎性细胞因子TNF-α及IL-6的分泌具有一定的抑制作用,提示PYY可能通过抑制炎性细胞因子的分泌而抑制炎症性疾病的发生发展。  相似文献   
202.
本试验旨在研究聚乙二醇(PEG)修饰猪胰高血糖素样肽-2(pGLP-2)对结肠炎小鼠肠道紧密连接蛋白和炎性因子基因表达的影响.试验选取24只BALB/C小鼠,随机分为4组,葡聚糖硫酸钠(DSS)组小鼠饮用3% DSS建立小鼠结肠炎模型,DSS +pGLP-2组和DSS+ PEG-pGLP-2组饮用3% DSS且在试验第8天腹腔分别注射pGLP-2和PEG-pGLP-2,饮水组小鼠正常饮水.试验期10 d.结果表明:与饮水组相比,DSS组小鼠结肠紧密连接闭锁小带基因(ZO-1)的mRNA相对表达量极显著降低(P<0.01);与DSS组相比,注射pGLP-2对ZO-1的mRNA相对表达量没有改善(P>0.05),而注射PEG-pGLP-2可极显著增加ZO-1的mRNA相对表达量(P<0.01).与饮水组相比,DSS组小鼠结肠白细胞介素-6(IL-6)、白细胞介素-10(IL-10)和干扰素-γ基因(INF-γ)的mRNA相对表达量极显著增加(P<0.01);与DSS组相比,注射pGLP-2和PEG-pGLP-2可极显著降低IL-6、IL-10和IFN-γ的mRNA相对表达量(P<0.01).结果提示,PEG-pGLP-2通过增加肠道紧密连接蛋白的表达、降低结肠炎小鼠炎性细胞因子的表达抑制其炎性病变,且作用效果优于pGLP-2.  相似文献   
203.
Japanese Black (JB) calves are more susceptible to infectious diseases compared to Holstein (Hol) calves. To clarify the immunological differences between JB and Hol calves, expression of cytokine messenger RNA (mRNA) was examined using peripheral CD4+, CD8+ and γδ T cells. Healthy calves, 24 from each species, were examined. Blood samples were obtained from calves at 1 week, 1 month and 3 months old, eight calves for each age of each species. Peripheral blood mononuclear cells were stimulated with phytohemagglutin (PHA), and T cell subsets were isolated by positive selection using magnetic cell sorting (MACS). Levels of interlekin (IL)‐2, IL‐4, IL‐10 and interferon (IFN)‐γ mRNA in three T cell subsets were analyzed. WC1‐N1+ γδ T cell percentages were significantly lower in JB calves at 1 week and 1 month of age compared to Hol calves. In addition JB calves had significantly lower IL‐2, IL‐10 and IFN‐γ mRNA in WC1‐N1+ γδ T cells at 1 and 3 months of age, whereas there were no significant differences in cytokine mRNA of CD4+ and CD8+ cells between the two groups. Decreased cytokine mRNA and cell number of peripheral γδ T cells may affect negatively on the immune system of JB calves.  相似文献   
204.
目的:观察五味地龙汤对哮喘血清白细胞介素-4(IL-4)水平的影响,以探讨其治疗机制。方法:取豚鼠48只,随机分为正常对照组,哮喘模型组,地塞米松组,小青龙汤组,五味地龙汤大、小剂量组,每组8只。卵白蛋白(OVA)腹腔注射致敏,气道吸入激发建立哮喘动物模型。按豚鼠IL-4 ELISA试剂盒说明,采用双抗夹心ELISA法,测定血清IL-4含量。结果:哮喘模型组豚鼠OVA致敏并激发后出现活动减少,反应迟钝,毛色失去光泽,呼吸次数增加,呼吸困难。IL-4测定结果显示,五味地龙汤大剂量组豚鼠血清IL-4浓度为(9.27±0.86)pg·ml-1,五味地龙汤小剂量组血清IL-4浓度为(10.77±1.17)pg·ml-1,地塞米松组血清IL-4含量(9.40±2.91)pg·ml-1,与哮喘模型组(13.37±1.86)pg·ml-1比较,差异均有显著性(P<0.01)。小青龙汤组血清IL-4含量为(10.94±1.30)pg·ml-1,与哮喘模型组比较,差异亦有显著性(P<0.05)。各药物组与正常对照组(10.45±0.62)pg·ml-1比较,均无统计学意义(P>0.05)。结论:五味地龙汤能降低哮喘动物血清IL-4含量。这可能是五味地龙汤能抑制炎症介质的释放、治疗气道炎症的机制之一。  相似文献   
205.
目的:探讨厚朴酚对5—脂氧合酶活性的影响.以阐明其抗炎机理。方法:以大鼠胸腔白细胞为材料,分别用高效液相色谱法和荧光分光光谱法测定白三烯B4(LTB4),5—羟二十碳四烯酸(5—HETE)的生成和细胞内钙离子水平。结果:厚朴酚对白细胞LTB4和5—HETE的生物合成有较强的抑制作用,其IC50值分别为8.5μmol/L和3.1μmol/L;厚朴酚还可以抑制趋化三肽(fMLP)刺激的白细胞内钙升高.但对静息状态的白细胞内钙离子水平没有明显的影响。结论:厚朴酚可以明显影响白细胞的功能,抑制炎性介质LTB4和5—HETE的生成,提示此功能与其抗炎作用机理有关。  相似文献   
206.
This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions; biochemical, redox status and histopathological alterations; and upregulation of inflammatory cytokines (interleukin (IL)-1β and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens.  相似文献   
207.
208.
Pathogenic infections increase morbidity and reduce performance in livestock, and thus understanding the comprehensive physiological changes associated with infections can benefit production sustainability. In this study, we sought to investigate such physiological responses to an acute immune challenge in lambs. Polypay wethers received single IV injections of 1.5 µg/kg lipopolysaccharide endotoxin (LPS-injected; n = 6) or saline (controls; n = 6). Corneal temperatures (via infrared thermography), rectal temperatures, blood, plasma, and saliva were assessed every 2 hr for 10 hr after injections. Blood was also assessed at 24 hr. LPS-injected lambs exhibited elevated (P < 0.05) corneal and rectal temperatures that peaked at 4 hr but were still slightly greater (P < 0.05) than controls at 10 hr. Circulating total white blood cells, monocytes, and granulocytes were reduced (P < 0.05) in LPS-injected lambs within the first 4 hr but were subsequently greater (P < 0.05) than in controls. Lymphocytes were reduced (P < 0.05) in LPS-injected lambs over the first 8 hr and did not differ from controls thereafter. Red blood cells, hematocrit, and hemoglobin were increased (P < 0.05) in LPS-injected lambs over the first 6 hr, indicating mild dehydration. Blood glucose briefly increased (P < 0.05) in LPS-injected lambs at 2 hr but was less (P < 0.05) than in controls thereafter. Blood lactate was greater (P < 0.05) in LPS-injected lambs between 6 and 10 hr after injections, which together with reduced (P < 0.05) CO2 partial pressure indicated a metabolic shift toward glycolysis. LPS-injected lambs exhibited a transient increase (P < 0.05) in plasma TNFα at 2 and 4 hr only and sustained increases (P < 0.05) in CXCL9 and CXCL10 beginning at 6 and 4 hr, respectively. They also exhibited a mild, paradoxical increase (P < 0.05) in the anti-inflammatory sFRP3. Salivary TNFα was increased (P < 0.05) in LPS-injected lambs at 2 hr only. Regression analyses indicated that rectal temperatures were a generally poor predictor of the other inflammatory components in this study, with the exception of circulating leukocyte populations. Likewise, correlations among the 10 cytokines measured in this study were generally weak, with notable exceptions between CXCL9 and CXCL10 and between IL-21 and IFNγ. These findings demonstrate that physiological changes to even short-lived immune challenges are dynamic in nature and persist beyond the time frame of febrile responses and other common assessments.  相似文献   
209.
BackgroundPseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear.ObjectivesOur study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection.MethodsKunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi.ResultsAt 105–106 TCID50 PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRV-infected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 102 TCID50 of PRV produced a significant inflammatory mediator increase.ConclusionsAn inflammatory model induced by PRV infection was established in mice, and 102 TCID50 PRV was considered as the best concentration for the establishment of the model.  相似文献   
210.
试验旨在探讨不同来源的传染性支气管炎病毒(Infectious bronchitis virus,IBV)诱导SPF鸡发病的免疫机制。选用140只1日龄SPF白来航鸡,随机分为4组,3组攻毒组通过滴鼻点眼途径分别接种鸡源IBV强毒株、鸡源IBV弱毒株和野鸡源IBV毒株3个毒株,对照组以同种方式接种等量灭菌的磷酸盐缓冲液。在感染后12 h、36 h、72 h、7 d和14 d,每组随机选取5只进行剖检,并分别采集法氏囊、肾脏和气管组织,剩余鸡用于观察临床症状、发病及死亡情况。应用实时荧光定量PCR检测攻毒后不同时间点采集的各组织中IBV的病毒载量、Toll样受体(Toll-like receptors,TLRs)及部分细胞因子(白细胞介素(interleukin,IL)和干扰素(interferon,IFN))表达量的变化。结果显示,感染不同来源IBV毒株之后仅鸡源IBV强毒株感染组SPF鸡出现抑郁、翅膀下垂、甩头等典型的临床症状,且在感染后5~10 d共有7只死亡,死亡率为20%。病理剖检发现,感染鸡源IBV强毒株的鸡肾脏肿大、尿酸盐沉积和有花斑样病变,而感染野鸡源IBV毒株、鸡源IBV弱毒株和对照组的鸡无明显的眼观病变。实时荧光定量PCR结果显示,在鸡源IBV强毒株组的法氏囊、肾脏和气管3个组织中均检测到病毒。对照组和野鸡源IBV毒株组中均未检测到病毒,鸡源IBV弱毒株组只在部分组织中检测到病毒。在感染后72 h,鸡源IBV强毒株组与其他各组相比,TLR1、TLR2、TLR3、TLR5、TLR7和TLR15基因在法氏囊中的表达量均显著升高(P<0.05),IL-6和IFN-β参与更强烈的抗病毒免疫反应;在感染后7 d,鸡源IBV弱毒株组与其他各组相比,肾脏中TLR2、TLR3、TLR15、TLR21、IL-6和IL-18基因表达量均显著升高(P<0.05)。野鸡源IBV感染后36 h法氏囊组织中IFN-γ基因表达量显著上调(P<0.05)。综上所述,3个IBV毒株中仅鸡源IBV强毒感染引起SPF鸡典型临床发病症状与可视组织病变,且可提高SPF鸡组织中免疫相关因子的基因表达量。本研究结果揭示,不同来源的IBV对SPF鸡的不同致病性与其感染诱导的免疫反应不同有关。  相似文献   
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