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211.
试验旨在研究大肠杆菌(E.coli)对奶牛子宫内膜上皮细胞(bovine endometrial epithelial cells,BEECs)的体外炎性损伤,探究大肠杆菌引发炎性反应的最佳浓度、作用时间及机制。首先,用不同浓度的大肠杆菌(5×104、5×105、1×106、2.5×106、5×106 CFU/mL)诱导刺激细胞3、6和9 h,通过倒置显微镜观察细胞形态、CCK-8法测D450 nm值,检测大肠杆菌对细胞活性的影响;其次,用不同浓度的大肠杆菌(5×104、5×105 CFU/mL)处理细胞3、6和9 h,用ELISA方法检测细胞上清液中白介素-1β(IL-1β)、IL-6、IL-8和肿瘤坏死因子-α(TNF-α)的分泌量;最后,用不同浓度的大肠杆菌(5×104、5×105 CFU/mL)处理细胞6和9 h,用Western blotting检测核因子κB抑制蛋白α(IκBα)和p65蛋白的磷酸化水平。结果显示,与对照组相比,大肠杆菌感染细胞9 h后,1×106、2.5×106和5×106 CFU/mL大肠杆菌组细胞活性均极显著降低(P<0.01),5×105 CFU/mL大肠杆菌组显著降低(P<0.05);大肠杆菌感染细胞9 h后,5×105 CFU/mL大肠杆菌组IL-1β、IL-6、IL-8和TNF-α极显著升高(P<0.01);大肠杆菌感染细胞6 h后,5×105 CFU/mL大肠杆菌组IκBα、p65蛋白磷酸化水平和IL-6均极显著升高(P<0.01),5×104 CFU/mL大肠杆菌组IκBα和p65蛋白磷酸化水平显著升高(P<0.05)。结果表明,大肠杆菌可以刺激奶牛子宫内膜上皮细胞产生炎性反应,且当细胞与5×105 CFU/mL大肠杆菌作用6 h或与5×104 CFU/mL大肠杆菌作用9 h为最佳。 相似文献
212.
为探究Ⅳ型分泌系统在布鲁氏菌(Brucella)感染过程中的作用,深入了解布鲁氏菌Ⅳ型分泌系统在疫苗开发中的潜力,本研究以牛种布鲁氏菌A19疫苗株为研究对象,使用A19 VirB启动子缺失株感染小鼠树突状细胞(DCs),通过菌落计数(CFU)评估Ⅳ型分泌系统对布鲁氏菌黏附侵袭及胞内生存的影响,同时对感染的细胞进行RNA和总蛋白的提取,分别通过实时荧光定量PCR和Western blotting检测自噬基因Beclin-1的转录和表达情况;收集感染后的细胞上清液,利用ELISA检测炎症因子白细胞介素-6(IL-6)和IL-10的分泌水平。黏附侵袭结果显示,布鲁氏菌VirB启动子缺失株与亲本株A19的黏附侵袭水平无显著差异(P>0.05);胞内生存试验发现,感染的4 h,布鲁氏菌VirB启动子缺失株的胞内存活能力显著低于亲本株A19(P<0.05),感染后0、24和48 h极显著低于亲本株A19(P<0.01);实时荧光定量PCR和Western blotting结果显示,感染后4、8和12 h,布鲁氏菌VirB启动子缺失株刺激细胞产生Beclin-1的水平极显著高于亲本株A19(P<0.01);ELISA结果显示,感染后8和12 h,布鲁氏菌VirB启动子缺失株刺激细胞产生IL-6的水平显著高于亲本株A19(P<0.05),而在感染后8和12 h,布鲁氏菌VirB启动子缺失株刺激细胞分泌IL-10的水平显著低于亲本株A19(P<0.05),感染24 h时极显著低于亲本株A19(P<0.01)。综上所述,当VirB启动子缺失后,布鲁氏菌对DCs的黏附侵袭能力并未明显改变,但显著降低了布鲁氏菌在DCs内的存活能力,提升了DCs的自噬水平,促进了DCs IL-6的分泌,抑制了IL-10的分泌。本研究初步探究了布鲁氏菌Ⅳ型分泌系统在感染DCs过程中的生物学作用,为后续布鲁氏菌疫苗改造研究奠定了理论基础。 相似文献
213.
214.
Sina Marsilio Shelley J. Newman James Scot Estep Paula R. Giaretta Jonathan A. Lidbury Emma Warry Andi Flory Paul S. Morley Katy Smoot Erin H. Seeley Matthew J. Powell Jan S. Suchodolski Jörg M. Steiner 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):669-677
215.
〔摘要〕目的探讨金英胶囊对慢性盆腔炎湿热证(湿热蕴结、湿热疲结)的临床疗效〔方法多中心临床观察
分两期进行,II期232例患者随机分为2组,对照组115例,治疗组117例;III期480例患者随机分为2组,对照
组120例,治疗组360例,对照组均}}服妇炎净胶囊和妇炎净模拟药,治疗组}}服金英胶囊,4周为1个疗程,1个
疗程后统计疗效,观察两组临床疗效及安全性〔结果经PP , I1"1''分析与对照组患者比较,临床症状明显改善,疗效
显著,差异无统计学意义(P>0.05)。结论金英胶囊对慢性盆腔炎属湿热证(湿热蕴结、湿热疲结)疗效安全可靠〔 相似文献
216.
Reasons for performing study: Efficacy of medications for recurrent airway obstruction is typically tested using clinical, cytological and lung function examinations of severely affected animals. These trials are technically challenging and may not adequately reflect the spectrum of disease and owner complaints encountered in clinical practice. Objective: To determine if owners of horses with chronic airway disease are better able to detect drug efficacy than a veterinarian who clinically examines horses infrequently. Method: In a double‐blinded randomised controlled trial, owners and a veterinarian compared the efficacy of dexamethasone (0.1 mg/kg bwt per os, q. 24 h, for 3 weeks; n = 9) to placebo (n = 8) in horses with chronic airway disease. Before and after treatment, owners scored performance, breathing effort, coughing and nasal discharge using a visual analogue scale (VAS). The clinician recorded vital parameters, respiratory distress, auscultation findings, cough and nasal discharge, airway mucus score, bronchoalveolar lavage fluid (BALF) cytology and arterial blood gases. Results: The VAS score improved significantly in dexamethasone‐ but not placebo‐treated horses. In contrast, the clinician failed to differentiate between dexamethasone‐ and placebo‐treated animals based on clinical observations, BALF cytology or endoscopic mucus score. Respiratory rate (RR) and arterial oxygen pressure (PaO2) improved with dexamethasone but not placebo. Conclusions and clinical relevance: In the design of clinical trials of airway disease treatments, more emphasis should be placed on owner‐assessed VAS than on clinical, cytological and endoscopic observations made during brief examinations by a veterinarian. Quantifiable indicators reflecting lung function such as RR and PaO2 provide a good assessment of drug efficacy. 相似文献
217.
目的:研究金银花及其不同提取物对炎性反应细胞模型抗炎作用。方法:将金银花及其不同提取物按一定浓度添加到用大肠杆菌滤过液制作的炎性反应细胞模型中,观察细胞形态的变化。结果:金银花黄酮类致使细胞全部裂解破碎;金银花绿原酸类及其水提液组细胞生长旺盛,形态规整,与对照组基本相同。在高浓度菌液中,金银花绿原酸类炎性反应细胞模型的细胞形态有不同程度的改变,稀疏,聚集,较对照组差,随后有圆形细胞产生,而加有金银花水提液的细胞与对照组基本相同。结论:大肠杆菌滤过液随着浓度的升高对细胞形态的改变愈加显著。金银花黄酮类物质对细胞有损害作用,而金银花绿原酸类物质及其水提液在体外有很强的抗炎性反应作用。在高浓度菌液中,金银花水提液的抗炎效果比金银花绿原酸类好。 相似文献
218.
【目的】以葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)小鼠为模型,探究辣木叶总黄酮(MOLF)对UC的防治作用。【方法】将50只BALB/c小鼠随机分为5组:对照组、DSS组(模型组)和MOLF-L(25 mg/kg)、MOLF-M(50 mg/kg)、MOLF-H(100 mg/kg)处理组,每组10只。小鼠通过饮用4%DSS诱导UC模型,各MOLF处理组灌胃相应剂量药物0.2 mL,对照组和DSS组灌以等体积的生理盐水,每天1次,连续7 d。每天记录各组疾病活动指数(DAI),在末次给药的次日经眼眶静脉丛采血,分离血清测定白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、白细胞介素-10(IL-10)、高迁移率族蛋白B1(HMGB1)和内毒素(LPS)含量;小鼠脱颈处死后取结肠组织进行HE染色观察组织形态、PAS染色观察组织杯状细胞数量变化;实时荧光定量PCR法检测结肠组织中IL-1β、TNF-α、IL-10、HMGB1 mRNA表达水平;免疫荧光法检测肠黏膜闭锁连接蛋白-1(ZO-1)和闭合蛋白(Occludin)表达情况;Western blotting分析凋... 相似文献
219.
Natalya N. Besednova Boris G. Andryukov Tatyana S. Zaporozhets Tatyana A. Kuznetsova Sergey P. Kryzhanovsky Svetlana P. Ermakova Irina V. Galkina Mikhail Yu. Shchelkanov 《Marine drugs》2022,20(4)
Inflammatory reactions are part of a complex biological response that plays a vital role in the appearance of various stimuli resulting from tissue and cell damage, the invasion of pathogenic bacteria, and the formation of the subsequent adaptive immune response. The production of many triggers and mediators of inflammation, which are inducers of pro-inflammatory factors, is controlled by numerous differentiation programs, through which inflammation is resolved and tissue homeostasis is restored. However, prolonged inflammatory responses or dysregulation of pro-inflammatory mechanisms can lead to chronic inflammation. Modern advances in biotechnology have made it possible to characterize the anti-inflammatory activity of phlorotannins, polyphenolic compounds from brown seaweed, and the mechanisms by which they modulate the inflammatory response. The purpose of this review is to analyze and summarize the results of numerous experimental in vitro and in vivo studies, illustrating the regulatory mechanisms of these compounds, which have a wide range of biological effects on the body. The results of these studies and the need for further research are discussed. 相似文献
220.
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