清燥救肺汤及其分解剂对肺炎支原体感染小鼠肺部炎症相关因子的影响

目的 探讨清燥救肺汤(QJD)及其分解剂对肺炎支原体(MP)感染小鼠血清中TNF-α、INF-γ含量及肺组织中MPN372、P1、AQP5表达的影响,明确其抗MP感染的分子机制。方法 将144只SPF级BABL/c小鼠随机分成正常组(A组)、模型组(B组)、QJD组(C组)、QJD分解剂I组(D组)、QJD分解剂II组(E组)及阿奇霉素组(F组),每组24只。除A组外,对其余5组小鼠进行MP感染模型处理,造模后分别予对应分组药物灌胃治疗,于造模后第3、7、10、14天进行取材。镜下观察小鼠肺组织病理切片,对小鼠肺组织病理炎症程度进行评分;并计算小鼠肺指数及干湿比;采用q PCR法对MPN372、P1基因含量进行测定;酶联免疫吸附试验(ELISA)测定各组小鼠血清TNF-α、INF-γ水平变化;Western blot法检测AQP5蛋白的表达。结果 MP感染后,镜下可见肺泡间隔增厚,细支气管壁增厚,大量炎症细胞浸润;其肺指数升高,干湿比降低;TNF-α、INF-γ的含量呈升高趋势,并于第7天达到峰值;AQP5的蛋白表达呈回落趋势,于第14天开始逐渐升高;与B组比较,从第7天开始,C组能够下调MPN372、P1及TNF-α的表达水平,上调INF-γ、AQP5的表达水平;其中D组的作用主要表现在下调MPN372、P1、TNF-α的表达,E组的作用主要表现在上调INF-γ、AQP5的表达。结论 QJD可以控制MP感染后肺部炎症,减少MP毒素MPN372的产生和P1黏附蛋白的表达;上调INF-γ、AQP5蛋白表达,下调TNF-α的表达,是其作用机制之一。     

IL-1、IL-6、TNF-α及IFN-γ在脾肾阳虚型溃疡性结肠炎模型大鼠血清及组织中的表达

目的通过对脾肾阳虚型溃疡性结肠炎(UC)模型大鼠血清及结肠组织中IL-1、IL-6、TNF-α及IFN-γ表达水平的检测,探讨它们在UC发生发展过程中的作用。方法采用灌服大黄水煎液+肌肉注射氢化可的松并结合TNBS(2,4,6-三硝基苯磺酸)+乙醇灌肠建立脾肾阳虚型UC动物模型。将60只大鼠随机分为空白组、脾肾阳虚型UC模型7、14d及21d组,采用酶联免疫法检测各组大鼠血清及结肠组织中IL-1、IL-6、TNF-α及IFN-γ的含量。结果与空白组比较,脾肾阳虚型UC模型组大鼠血清及结肠组织中IL-1、IL-6、TNF-α及IFN-γ含量明显升高(P0.05);尤以模型21d组最为明显。结论促炎性细胞因子IL-1、IL-6、TNF-α及IFN-γ在脾肾阳虚型UC发病过程中起重要作用。     

水浸束缚应激模型在小鼠结肠损伤研究中的探索与实践

目的 探索不同造模时间对水浸束缚应激(water immersion restraint stress, WIRS)模型小鼠结肠损伤程度的影响，对比研究病理损伤程度和肠道菌群构成。方法 本研究共用34只KM小鼠，首先将18只小鼠随机分为对照组和WIRS4 h、12 h、24 h、36 h、48 h组，造模结束后，通过HE染色观察不同造模时间的结肠损伤程度。评估出较优的造模时间后，将16只小鼠随机分为对照组和WIRS24 h组，使用ELISA法检测结肠肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-6(interleukin-6,IL-6)、γ干扰素(interferon-γ,IFN-γ)含量，使用16S rRNA测序检测结肠内容物的菌群组成改变。结果 WIRS各组结肠腔均出现不同程度弥漫性充血和泛红，HE染色显示WIRS小鼠出现炎症细胞浸润等病理改变。WIRS24 h组损伤较明显，与WIRS36 h、48 h组相比小鼠成活率高，TNF-α、IL-6、IFN-γ水平均显著升高(P<0.0001)。与对照组相比，WIRS24 h组小鼠结肠菌...     

防风不同极性部位对腹泻大鼠的止泻作用和结肠不同亚型AQP的调控

为了观察防风不同极性部位对腹泻大鼠止泻作用和对结肠不同亚型水通道蛋白(aquaporin, AQP)影响的比较,将80只SD大鼠随机分为正常组、模型组、地芬诺酯组、防风石油醚萃取部位组、乙酸乙酯萃取部位组、正丁醇萃取部位组、水溶性部位组和总提取物组,每组10只、除正常组外其余各组每天灌胃番泻叶水煎液,连续7天,于第8天开始各组大鼠上午灌胃番泻叶,下午灌胃相应药物,正常组与模型组给予等体积的2%吐温-80溶液,连续给药7天。观察大鼠排便情况,检测大鼠血清中电解质含量和二胺氧化酶(diamine oxidase, DAO)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、Na~+-K~+-ATPase水平,苏木精-伊红(hematoxylin-eosin, HE)染色观察结肠病理形态学变化,Western blot分析结肠中不同亚型AQP的表达情况。结果显示防风石油醚萃取部位、正丁醇萃取部位和总提取物组可降低大鼠的腹泻指数,增加血清中Na~+和K~+浓度及结肠组织中Na~+-K~+-ATPase的活性,降低血清DAO和TNF-α的水平,改善结肠黏膜损伤,上调结肠组织中AQP-3、AQP-4和AQP-8的蛋白表达;防风石油醚部位还可下调结肠组织中AQP-9的蛋白表达水平。综上表明,防风具有较好的止泻作用,石油醚部位和正丁醇部位是其止泻的活性部位,且二者对肠道不同亚型的AQP调控具有差异。     

肠道菌群变化对肠上皮细胞Myd88蛋白及 炎症因子的影响

目的研究肠道菌群变化对体外培养的正常大鼠肠黏膜上皮细胞Myd88蛋白水平及其下游TNF-α等炎症因子的影响。方法选取10只健康大鼠,实验室适应性喂养5d后继续常规喂养7d并处死,取结肠组织进行细胞培养得到原代肠黏膜上皮细胞,将所得细胞分为5组,分别用正常细胞培养液(A组)、正常大鼠肠腔菌溶液(B组)、正常大鼠黏膜菌溶液(C组)、溃疡性结肠炎大鼠肠腔菌溶液(D组)、溃疡性结肠炎大鼠黏膜菌溶液(E组)培养,通过蛋白质印迹法检测各组细胞中Myd88蛋白含量,通过酶联免疫吸附法检测TNF-α和IL-6含量。结果 D组、E组与A组比较,细胞中Myd88蛋白及TNF-α、IL-6水平显著增高(Ps0.01),D、E组与B、C组比较Myd88蛋白及TNF-α、IL-6水平亦显著增高(Ps0.01),而B组、C组相较于A组差异无统计学意义(Ps0.05)。进一步比较D组与E组、B组与C组间Myd88蛋白及TNF-α、IL-6水平差异亦无统计学意义(Ps0.0.5)。结论 (1)肠道菌群结构的改变可引起肠黏膜细胞Myd88通路的激活及炎症因子的释放。(2)肠道中细菌种类、数量、分布位置等因素的综合变化与肠黏膜炎症反应的发生关系密切。     

呼吸机相关性肺炎患者病原菌分布及IL 35的炎症控制机制

目的探讨呼吸机相关性肺炎(VAP)患者病原菌分布及白细胞介素35(IL-35)的炎症控制机制。方法回顾性分析2016年12月至2018年12月在我院重症监护病房(ICU)行机械通气的152例患者的临床资料,根据是否发生VAP将其分为VAP组(n=70)和对照组(n=82)。收集VAP患者痰液进行细菌培养及药敏实验,检测并比较两组患者外周血单个核细胞(PBMCs)中CD4~+CD25~+CD127dim/-调节性T细胞(Tregs)比例及血清中白细胞介素35(IL-35)、肿瘤坏死因子α(TNF-α)、干扰素-γ(IFN-γ)水平;同时检测并比较经佛波酯和重组人IL-35刺激后的Tregs细胞培养液上清中IL-35、IFN-γ、TNF-α水平。结果 70例VAP患者共检出病原菌128株,其中革兰阴性菌占82.81%,革兰阳性菌占14.84%,真菌占2.34%。鲍曼不动杆菌对头孢西丁的耐药率最高,对头孢哌酮的耐药率最低。铜绿假单胞菌对头孢西丁的耐药率最高,对亚胺培南的耐药率最低。肺炎克雷伯菌对头孢西丁的耐药率最高,对头孢哌酮的耐药率最低。VAP组患者PBMCs中CD4~+CD25~+CD127dim/-Tregs比例及血清中IL-35、IFN-γ、TNF-α水平显著高于对照组(t=12.675、36.631、13.464、8.482,均P0.001)。经重组人IL-35刺激后的Tregs细胞培养液上清中IL-35水平显著高于佛波酯刺激后(t=8.886,P0.001)。经重组人IL-35刺激后的Tregs细胞培养液上清中IFN-γ、TNF-α水平显著低于佛波酯刺激后(t=14.091、7.588、均P0.001)。结论呼吸机相关性肺炎病原菌以革兰阴性菌为主,呈现多药耐药性,临床应合理使用抗菌药物以防治呼吸机相关性肺炎。IL-35可通过调控Tregs功能降低促炎因子分泌从而在呼吸机相关性肺炎发病过程中发挥抗炎症作用,提示IL-35可能为呼吸机相关性肺炎的治疗提供新的方向。     

免疫致敏结合局部乙酸刺激法建立大鼠溃疡性结肠炎模型

目的结肠黏膜组织致敏法加乙酸局部刺激法建立复合大鼠溃疡性结肠炎模型。方法30只Wistar大鼠随机分为正常对照组、模型对照组、用药组(各10只),用结肠黏膜组织致敏法加乙酸局部刺激法建立大鼠复合溃疡性结肠炎模型后,用药组给予SASP灌胃,模型对照组和正常对照组给予生理盐水,均灌胃2周后处死大鼠,分离其结肠组织和血清。生化法检测各组结肠中MDA、SOD、GSH-PX、NO、TNOS和iNOS值,放免法测定大鼠血清及结肠IL-4及TNF-α含量变化,酶联免疫法测定大鼠血清IFN-γ含量变化。结果与空白对照组比较,模型组大鼠结肠组织MDA、NO、TNOS及iNOS含量升高,SOD、GSH-Px水平显著降低。与模型组比较,SASP组SOD、GSH-Px计数水平显著升高,组织MDA、NO、TNOS及iNOS含量降低。模型组血清和结肠IL-4含量较对照组明显降低,而模型大鼠血清和结肠TNF-α含量明显升高,模型组大鼠血清IFN-γ含量明显升高。SASP组IL-4含量升高,TNF-α和IFN-γ含量明显降低。结论改进的复合造模方法,可以较好的模拟人类UC病变的慢性活动性特点,适合药效观察和评价。     

地榆对急性溃疡性结肠炎大鼠肠道菌群的影响

本实验旨在从肠道菌群角度探讨地榆对急性溃疡性结肠炎(UC)的保护作用及其初步机制。大鼠随机分为正常组、模型组及地榆低、高剂量组。采用3.5%葡聚糖硫酸钠(DSS)诱导急性UC模型,并予以灌胃给药。记录大鼠DAI疾病评分,HE染色观察组织形态变化,ELISA法检测炎症因子含量,高通量测序技术检测肠道菌群。结果显示,地榆可显著降低UC大鼠DAI疾病评分(P0.05),修复其结肠粘膜损伤,降低血清及结肠组织IL-6、IL-1β、TNF-α含量(P0.05);改善UC大鼠肠道菌群多样性,恢复菌群平衡。研究结果提示地榆可通过调节UC大鼠肠道菌群,修复结肠粘膜屏障,进而发挥治疗急性UC的作用。     

鹅去氧胆酸对多囊卵巢综合征大鼠内分泌状态及胰岛功能的影响CSCD

目的 探索鹅去氧胆酸（CDCA）对多囊卵巢综合征（PCOS）大鼠内分泌功能及胰岛功能的影响,为进一步完善PCOS的临床治疗提供基础。方法 选取30只SPF级SD大鼠为研究对象,分为对照组（5只）和模型组（25只）,模型组大鼠使用来曲唑—羧甲基纤维素钠混悬液灌胃构建大鼠PCOS模型,造模成功后将模型组大鼠分为PCOS组和PCOS+CDCA组。PCOS组继续予以来曲唑—羧甲基纤维素钠混悬液灌胃,PCOS+CDCA组在PCOS组基础上予以0.3 mL 0.25%鹅去氧胆酸钠灌胃。并在饲养第21天及饲养第42天,采用HE染色观察模型组大鼠的卵巢形态;获取大鼠的尾静脉血,检测其血清睾丸素水平、空腹血糖、空腹胰岛素及炎症因子水平,计算胰岛素抵抗指数的稳态模型评估（HOMA-IR）和β细胞功能的稳态模型评估（HOMA-β）指数;收集模型组大鼠的粪便分析肠道菌群中大肠埃希菌、变形杆菌、链球菌及革兰阳性杆菌的占比。采用Spearman相关性分析评估模型组大鼠肠道菌群与其卵巢囊性卵泡数量、血清睾丸素、HOMA-IR、HOMA-β、肿瘤坏死因子-α(TNF-α)及白介素-6(IL-6)的相关性。结果 模型组大鼠的囊性卵泡数量、血清睾丸素、HOMA-IR水平均显著高于对照组,HOMA-β水平显著低于对照组（均P<0.05）,血清炎症因子水平显著高于对照组（均P<0.05）。PCOS组大鼠的血清睾丸素、HOMA-IR及炎症因子水平显著高于PCOS+CDCA组大鼠,而HOMA-β水平显著低于PCOS+CDCA组大鼠（均P<0.05）。PCOS组大鼠肠道大肠埃希菌比例呈显著上升趋势,而变形杆菌、链球菌及革兰阳性杆菌比例呈显著下降趋势（均P<0.05）。在CDCA的作用下,PCOS+CDCA组大鼠肠道大肠埃希菌比例升高趋势显著减缓,变形杆菌、链球菌及革兰阳性杆菌比例下降趋势显著减缓（均P<0.05）;干预后PCOS+CDCA组大鼠的肠道大肠埃希菌占比显著低于PCOS组大鼠,而变形杆菌、链球菌及革兰阳性杆菌比例均显著高于PCOS组大鼠（均P<0.05）。PCOS组大鼠中,大肠埃希菌占比与囊性卵泡数量、血清睾丸素、HOMA-IR、TNF-α、IL-6均呈正相关,HOMA-β呈负相关（均P<0.05）;变形杆菌、链球菌及革兰阳性杆菌的占比与囊性卵泡数量、血清睾丸素、HOMA-IR、TNF-α、IL-6均呈负相关,与HOMA-β呈正相关（均P<0.05）。在PCOS+CDCA组大鼠中,大肠埃希菌占比与囊性卵泡数量、TNF-α均呈正相关（均P<0.05）,变形杆菌占比与血清睾丸素呈负相关（P<0.05）。结论 CDCA可以在一定程度上缓解PCOS大鼠的内分泌紊乱、胰岛素抵抗及机体炎症水平,而这些疾病状态的改变与肠道菌群的调节具有显著的相关性。     

溃疡性结肠炎小鼠肠道通透性改变与TNF-α及NF-κB P65的关系

目的：采用2.5%葡聚糖硫酸钠（DSS）定量灌胃诱导小鼠溃疡性结肠炎（UC）,观察小鼠结肠通透性改变与肿瘤坏死因子α（TNF-α）及NF-κB p65的关系。方法：48只ICR小鼠随机分为2组（n=24）：对照组和模型组。模型组小鼠给予2.5% DSS定量灌胃诱发小鼠急性UC,对照组小鼠予同体积的蒸馏水灌胃代替。记录两组小鼠疾病活动指数（DAI）,9 d后测定两组小鼠结肠组织病理学评分、结肠通透性、TNF-α及NF-κB p65。统计分析DAI、结肠通透性、TNF-α与NF-κB p65之间的相关性。结果：与对照组比较,模型组小鼠DAI、结肠病理学评分、结肠通透性、TNF-α、NF-κB p65均显著增高（P均<0.01）。小鼠DAI增高与结肠通透性密切相关（P均<0.01）,结肠通透性增高与TNF-α、NF-κB p65密切相关（P均<0.01）。结论：与对照组小鼠相比,DSS造模小鼠的结肠通透性显著增高,并与TNF-α、NF-κB p65增高呈正相关。TNF-α、NF-κB p65增高导致结肠通透性增高,进而导致炎症免疫反应过度增强,可能是UC发病的重要环节。     

PA-MSHA引起注射局部急性炎症及白细胞介素17、肿瘤坏死因子α和Toll样受体4的表达改变

为研究皮下注射铜绿假单胞菌甘露糖敏感血凝菌毛株(Pseudomonas aeruginosa mannose sensitive hemagglutinin,PA-MSHA)注射液后局部组织的病理学改变及白细胞介素17(interleukin 17,IL-17)、肿瘤坏死因子α(tumor necrosis factorα,TNF-α)和Toll样受体4(Toll-like receptor 4,TLR4)表达情况,将30只小鼠随机分为两组,分别皮下注射PA-MSHA和生理盐水,在注射后6、12、24、48及72h取注射局部组织,苏木精-伊红(hematoxylin-eosin,HE)染色后观察病理形态改变,并用免疫组化染色和图像分析检测IL-17、TNF-α和TLR4表达水平。结果显示,小鼠皮下注射PA-MSHA后,在给药部位引起以中性粒细胞浸润为主的急性炎症;局部炎症灶中IL-17、TNF-α和TLR4表达在注射后6h升高,24h达到高峰,然后逐渐减低,至72h实验组与对照组无差异;3种炎症因子的表达与炎症反应程度相平行。结果表明,皮下注射PA-MSHA能引起局部组织急性炎症反应,且能改变局部免疫状态。     

Picroside III,an Active Ingredient of Picrorhiza scrophulariiflora,Ameliorates Experimental Colitis by Protecting Intestinal Barrier Integrity

This study aims to explore the protective effects of Picroside III, an active ingredient of Picrorhiza scrophulariiflora, on the intestinal epithelial barrier in tumor necrosis factor-α (TNF-α) induced Caco-2 cells and dextran sulfate sodium (DSS) induced colitis in mice. Results show that Picroside III significantly alleviated clinical signs of colitis including body weight loss, disease activity index increase, colon shortening, and colon tissue damage. It also increased claudin-3, ZO-1 and occludin expressions and decreased claudin-2 expression in the colon tissues of mice with colitis. In vitro, Picroside III also significantly promoted wound healing, decreased the permeability of cell monolayer, upregulated the expressions of claudin-3, ZO-1 and occludin and downregulated the expression of claudin-2 in TNF-α treated Caco-2 cells. Mechanism studies show that Picroside III significantly promoted AMP-activated protein kinase (AMPK) phosphorylation in vitro and in vivo, and blockade with AMPK could significantly attenuate the upregulation of Picroside III in ZO-1 and occludin expressions and the downregulation of claudin-2 expression in TNF-α treated Caco-2 cells. In conclusion, this study demonstrates that Picroside III attenuated DSS-induced colitis by promoting colonic mucosal wound healing and epithelial barrier function recovery via the activation of AMPK.     

铜绿假单胞菌家兔肺部感染模型的建立与评价

目的:建立铜绿假单胞菌(PA,又名绿脓杆菌)肺部感染动物模型,并从病理学及细菌学、影像学等方面进行评价,研究铜绿假单胞菌对肺组织的致病作用。方法:24只健康清洁级新西兰大白兔随机分成2组,实验组采用经皮气管穿刺法,隔日注入铜绿假单胞菌反复感染家兔,对照组施以生理盐水。接种后隔日一次行胸部CT扫描。比较二组家兔的体温、血象及肺组织匀浆菌落计数;观察病理组织改变及胸部CT影像学变化。结果:注菌组家兔白细胞总数显著升高,肺组织匀浆菌落计数显著高于对照组。CT表现为双侧多发斑片状模糊影,部分可见实变及脓肿灶。大体标本可见家兔肺部结节、脓肿及出血灶,病理学镜下观察发现注菌组家兔肺组织内多个脓肿灶形成,大量中性粒细胞浸润,肺泡腔内大量渗出,部分出血,肺泡壁充血及肺水肿。随着注菌次数增多及时间推移,逐渐出现如肺泡间隔增厚、肉芽肿形成、实变等慢性肺部炎症的病理表现。结论:使用经皮气道穿刺法接种铜绿假单胞菌至新西兰兔肺部,可成功建立兔铜绿假单胞菌肺部感染模型。     

乳腺癌术后医院感染患者病原菌分布和危险因素及血清炎症因子水平分析

目的分析乳腺癌术后医院感染患者病原菌分布、危险因素及血清炎症因子水平,并探讨其临床意义。方法收集2016年3月至2018年3月我院诊治的80例乳腺癌术后医院感染患者为观察组。同期选取80例乳腺癌术后未发生感染者为对照组。利用全自动微生物分析仪对感染患者进行病原菌分布检测。对乳腺癌术后医院感染的危险因素进行单因素回归分析,同时检测并比较两组患者血清中白细胞介素-10(IL-10)、干扰素-γ(IFN-γ)及肿瘤坏死因子-α(TNF-α)的水平。结果80例乳腺癌术后医院感染患者共检出病原微生物97株。其中革兰阴性菌55株,以大肠埃希菌及铜绿假单胞菌为主;革兰阳性菌39株,以金黄色葡萄球菌为主(16株);真菌3株。观察组患者血清中IL-10、INF-γ及TNF-α水平均显著高于对照组(均P<0.05)。患者合并疾病情况、引流天数、住院天数及辅助化疗均与乳腺癌术后发生医院感染有密切联系(均P<0.05)。结论乳腺癌术后医院感染病原菌分布较广,以革兰阴性菌为主。患者合并疾病情况、引流天数、住院天数及辅助化疗均为医院感染的危险因素。血清中炎症因子水平可作为乳腺癌术后医院感染的诊断标志物。     

CD8＋CD122＋T细胞在脑缺血过程中作用的研究

目的：探讨CD8＋CD122＋T细胞在脑缺血过程中的作用及其机制。方法：线栓法建立小鼠大脑中动脉栓塞模型（MCAO）;激光共聚焦显微镜检测小鼠脑缺血组织中CD8＋CD122＋T细胞浸润情况;流式细胞仪检测脑缺血组织中CD8＋CD122＋T细胞／CD3＋T细胞的比例及脾和胸腺中CD8＋CD12TT细胞数量变化;RT—PCR方法检测CD8＋CD122＋T细胞对氧糖剥夺（Oxygen—glucosedeprivation,OGD）条件下星形胶质细胞表达TNF-α,IL-1β,IFN-γ的影响。结果：各时间点脑缺血组织中均有CD8＋CD122＋T胞浸润,且随脑缺血时间延长,缺血侧脑组织中CD8＋CD122＋T细胞／CD3＋T细胞比例逐渐增加,5d和7d组差异显著,与非缺血侧相比,P5d〈0．05,P7d〈0．05;MCAO小鼠脾及胸腺中CD8＋CD122＋T细胞呈现先增高后降低的趋势。星形胶质细胞经OGD处理后,与对照组相比,IFN-γ、TNF-α、IL—1β表达显著增高,PIFN-γ〈0．01、PTNF-α〈0．001、PIL-1β〈0．01;CD122-blocked组与CD8＋组相比,IFN-γ、TNF-α、IL-1β表达明显增高,PIFN-γ〈0．05、PINF-α〈0．05、PIL-1β〈0．01;CD8＋组与HBSS组相比,IFN-γ表达降低,P〈0．05;IL-1β表达有降低的趋势。结论：CD8＋CD122可细胞在脑缺血过程中发挥保护性作用,其保护作用通过CD122抑制星形胶质细胞TNF-α,IL-1β,IFN-γ炎症因子表达实现的。     

阿如拉-7味散对肠道菌群失调小鼠免疫功能及肠道菌群多样性的影响

目的 研究阿如拉-7味散对抗生素诱导肠道菌群失调小鼠的免疫功能和肠道菌群多样性的影响.方法 选取50只清洁级昆明小鼠,分为正常对照组、自然恢复组、阳性对照组、阿如拉-7味散低剂量组(0.5 g/mL)和阿如拉-7味散高剂量组(1.0g/mL).将所有小鼠用头孢曲松钠和盐酸林可霉素混合药液灌胃制备肠道菌群失调模型,第8天...     

oprM as a new target for reversion of multidrug resistance in Pseudomonas aeruginosa by antisense phosphorothioate oligodeoxynucleotides

Multidrug-resistant Pseudomonas aeruginosa (MDR-PA) is one of the leading Gram-negative organisms associated with nosocomial infections. The increasing frequency of MDR-PA has represented a huge challenge in conventional antibacterial therapy. The loss of effectiveness of commonly used antibiotics calls for the immediate need to develop an alternative strategy for combating MDR-PA infections. The multiantibiotic resistance of MDR-PA is largely attributable to the production of multidrug efflux pumps, MexAB-OprM. OprM forms the antibiotic-ejecting duct and plays a crucial role in exporting incoming chemotherapeutic agents across the membranes. Disruption of the OprM expression may inhibit the function of multidrug efflux pumps and lead to restoration of MDR-PA susceptibility to antibiotics. In this study, we developed a novel anion liposome for encapsulating and delivering specific anti-oprM phosphorothioate oligodeoxynucleotide (PS-ODN617) and polycation polyethylenimine (PEI) complexes. The additions of the encapsulated anti-oprM PS-ODN617/PEI to MDR-PA isolates caused a significant reduction of oprM expression and inhibition of MDR-PA growth in the presence of piperacillin in a concentration-dependent manner. The encapsulated PS-ODN617 treatment also reduced minimal inhibitory concentrations of five most commonly used antibiotics to the sensitive margin values on MDR-PA clinical isolates, respectively. The results of present study firstly indicate that PS-ODN targeted to oprM can significantly restore the susceptibility of MDR-PA to existing antibiotics, which appears to be a novel strategy for treating MDR-PA infections.     

Use of the rotating wall vessel technology to study the effect of shear stress on growth behaviour of Pseudomonas aeruginosa PA01

The biofilm phenotype of Pseudomonas aeruginosa enables this opportunistic pathogen to develop resistance to the immune system and antimicrobial agents. Pseudomonas aeruginosa biofilms are generated under varying levels of shear stress, depending on the infection site. In the lung mucus of cystic fibrosis (CF) patients, P. aeruginosa forms matrix-enclosed microcolonies which cause chronic infections representing the major cause of mortality in CF patients. The lung mucus of CF patients is probably characterized by low fluid shear as the main shear-causing factor, i.e. mucociliary clearance, is absent. In this study, the influence of fluid shear on the growth behaviour of P. aeruginosa PA01 was investigated using a low-shear suspension culture device, the rotating wall vessel (RWV). Cultivation in low shear induced a self-aggregating phenotype of P. aeruginosa PA01, resulting in the formation of biofilms in suspension similar to what has been described in CF mucus. The addition of a ceramic bead to the culture medium in the RWV created a higher-shear condition which led to the formation of surface-attached rather than suspension biofilms. In low-shear culture conditions, a significant increase of the rhl N -butanoyl- l -homoserine lactone (C₄-HSL) directed quorum sensing (QS) system, and the psl polysaccharide synthetic locus was demonstrated using gene expression analysis. Accordingly, the low-shear condition induced a higher production of rhamnolipids, which is controlled by the C₄-HSL QS-system and is known to play a role in CF lung pathology. These results indicate that fluid shear has an impact on the growth phenotype of P. aeruginosa which might play a role in CF lung infections caused by this bacterium.     

Analysis of Influence of Baicalin Joint Resveratrol Retention Enema on the TNF-α, SIgA,IL-2, IFN-γ of Rats with Respiratory Syncytial Virus Infection

Explore the influence of baicalin joint resveratrol retention enema on TNF-α, SIgA, IL-2, and IFN-γ of rats with respiratory syncytial virus (RSV) infection. The 60 SD rats were randomly divided into normal group, model group, baicalin group, resveratrol group, joint group, and ribavirin group. For model group, baicalin group, resveratrol group, joint group, and ribavirin group, rats were given RSV virus suspension intranasally for 3 days, and model group was not given administration. Baicalin group, resveratrol group, joint group, and ribavirin group were, respectively, given baicalin 100 mg/kg/day, resveratrol 30 mg/kg/day, baicalin joint resveratrol, and ribavirin 1 g/kg/day retention enema. After continuously given administration 7 days, rats were measured in serum TNF-α, IL-2, IFN-γ levels and SIgA levels in bronchoalveolar lavage fluid. Model group, TNF-α, IL-2, IFN-γ, and SIgA were significantly higher than the normal group (P < 0.05); Baicalin group, resveratrol group, ribavirin group, TNF-α, IL-2, IFN-γ, and SIgA were significantly higher than the model group (P < 0.05); TNF-α, IL-2 between baicalin group, resveratrol group, ribavirin group, have no significant difference (P > 0.05); Baicalin group, resveratrol group, joint group, IFN-γ, and SIgA were significantly higher than the ribavirin group (P < 0.05); Joint group TNF-α, IL-2, IFN-γ, and SIgA were significantly higher than baicalin group, resveratrol group, and ribavirin group (P < 0.05). Baicalin joint resveratrol retention enema can increase RSV infection model in rats serum TNF-α, IL-2, IFN-γ levels and SIgA levels in bronchoalveolar lavage fluid, which may anti-virus through this mechanism.     

Cytokines in rats experimentally infected with Trypanosoma evansi

The aim of this study was to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1) and interleukin 6 (IL-6) in the serum of rats experimentally infected with Trypanosoma evansi and to correlate these levels with hematological parameters. Initially, 48 rats (group T) were intraperitoneally inoculated with cryopreserved blood containing 1 × 10⁶ trypomastigotes per animal. Twenty-eight animals (group C) were used as negative controls and received 0.2 mL of saline by the same route. The experimental groups were formed according to the time after infection and the degree of parasitemia as follows: four control subgroups (C3, C5, C10 and C20) with seven non-inoculated animals each and four test subgroups (T3, T5, T10 and T20) with 10 animals each inoculated with T. evansi. The blood samples were collected by cardiac puncture at days 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) and 20 (C20, T20) post-infection (PI) to perform the complete blood count and the determination of IFN-γ, TNF-α, IL-1 and IL-6 levels using an ELISA quantitative sandwich. Infected rats showed normocytic normochromic anemia during the experimental period. T. evansi infection in rats caused a serum increase (P < 0.01) of IFN-γ, TNF-α, IL-1 and IL-6 levels at days 3, 5, 10 and 20 PI compared to the controls. The multiple linear regressions showed a reduction of 24% in the hematocrit as a consequence of the increased IFN-γ, TNF-α and IL-1. Therefore, we conclude that the infection caused by T. evansi causes an increase in the pro-inflammatory cytokines. These results suggest a synergism among IL-1, TNF-α and IFN-γ contributing to the development of anemia. This increase is associated with the regulation of immune responses against the parasite.