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31.
NEUMANN F. J.; OTT I.; WILHELM A.; KATUS H.; TILLMANNS H.; SCHoMIG A. 《European heart journal》1994,15(2):171-178
The study investigated inflamatory responses in evolving myocardialinfarction. Fifteen patients with acute myocardial infarction,who had undergone balloon recanalization of the infarct-relatedcoronary artery within 4 h after onset of symptoms, were examined.Blood samples were obtained through the guiding catheter andfrom the pulmonary artery before and immediately after successfulrecanalization. After recanalization, plas from the pulmonaryartery was 47% (quartiles: l9%, 78; P =0·001) more chemotacticto neutrophils from normal donors than before recanalization.Furthermore, significant changes in neutrophil function werefound in the pulmonary artery. Compared to the values beforerecanalization, the nitroblue tetrazolium score rose by 31%(quartiles: 4%, 37% P=0·003), FMLP-stimulated superoxideanion production by 10% (quartiles: 0%, 39% P=0·020),and chemotaxis by 46% (quartiles: 0%, 81%, P=0·011),while neutrophil filterability decreased by 28% (quartiles:15%, 47%; P=0·010). No significant changes in neutrophilparameters were found in the arterial blood The study indicatesthat chemoattractants are released in the early reperfusionperiod of evolving myocardial infarction. These chemoattractantsmay act as inflammatory mediators causing neutrophil activation. 相似文献
32.
Acute inflammatory responses to mechanical lesions in the CNS: differences between brain and spinal cord 总被引:7,自引:0,他引:7
Schnell L Fearn S Klassen H Schwab ME Perry VH 《The European journal of neuroscience》1999,11(10):3648-3658
Lesion-induced inflammatory responses in both brain and spinal cord have recently become a topic of active investigation. Using C57BL/6J mice, we compared the tissue reaction in these two central nervous system (CNS) compartments with mechanical lesions of similar size involving both grey and white matter. This evaluation included the quantitative assessment of neutrophils, lymphocytes and activated macrophages/microglia, as well as astrocyte activation, upregulation of vascular cell adhesion molecules (ICAM-1, VCAM-1, PECAM) and the extent of blood-brain barrier (BBB) breakdown. Time points analysed post-lesioning included 1, 2, 4 and 7 days (as well as 10 and 14 days for the BBB). We found clear evidence that the acute inflammatory response to traumatic injury is significantly greater in the spinal cord than in the cerebral cortex. The numbers of both neutrophils and macrophages recruited to the lesion site were significantly higher in the spinal cord than in the brain, and the recruitment of these cells into the surrounding parenchyma was also more widespread in the cord. The area of BBB breakdown was substantially larger in the spinal cord and vascular damage persisted for a longer period. In the brain, as in spinal cord, the area to which neutrophils were recruited correlated well with the area of BBB breakdown. It will be of interest to determine the extent to which the infiltration of inflammatory cells contributes, either directly or indirectly, to the vascular permeability and secondary tissue damage or, conversely, to local tissue repair in the brain and the spinal cord. 相似文献
33.
Hiroyasu Ishikura Yasunari Uedono Kazunobu Yamagami Takashi Arai Naoshi Takeyama Takaya Tanaka 《Surgery today》1996,26(9):694-699
We examined the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cefmetazole sodium on survival, neutrophil count, and neutrophil function in rats with peritonitis produced by cecal ligation and puncture. Rats with peritonitis received either rhG-CSF (50 or 100 g/kg) with or without cefmetazole (50 mg/kg) for 3 days, cefmetazole alone, or no treatment and were evaluated as controls. The mortality rate of all treated rats was significantly lower than that of the untreated rats. The survival rate was 57.1% for the rats given both rhG-CSF and cefmetazole, but there was no significant improvement of survival as compared with cefmetazole therapy alone. Treatment with rhG-CSF at 100 |Gmg/kg caused the circulating neutrophil count to increase significantly. The phagocytic activity for latex beads and neutrophil H2O2 production showed a greater enhancement by phorbol myristate acetate (PMA) in the untreated rats, thus indicating that neutrophils from treated rats were more activated. These findings show that rhG-CSF can improve survival and neutrophil function in rats with peritonitis, while combined therapy with cefmetazole was also found to be beneficial. 相似文献
34.
Steven B Yee Umesh M Hanumegowda Jon A Hotchkiss Patricia E Ganey Robert A Roth 《Toxicological sciences》2003,72(1):43-56
Synergistic liver injury develops in Sprague-Dawley rats from administration of a small, noninjurious dose (7.4 x 10(6) EU/kg) of bacterial lipopolysaccharide (LPS) given 4 h after a nontoxic dose (100 mg/kg) of the pyrrolizidine alkaloid, monocrotaline (MCT). Previous studies demonstrated that liver injury is mediated through inflammatory factors, such as Kupffer cells and tumor necrosis factor alpha (TNF-alpha), rather than through simple interaction between MCT and LPS. In the present study, the hypothesis that neutrophils (polymorphonuclear leukocytes or PMNs) are causally involved in this injury model is tested, and the interdependence between PMNs and other inflammatory components is explored. Hepatic PMN accumulation and the appearance of cytokine-induced neutrophil chemoattractant-1 in plasma preceded the onset of liver injury, suggesting that PMNs contribute to toxicity. Hepatic PMN accumulation was partially dependent on TNF-alpha. Prior depletion of PMNs in MCT/LPS-cotreated animals resulted in attenuation of both hepatic parenchymal cell (HPC) and sinusoidal endothelial cell (SEC) injury at 18 h. PMN depletion did not, however, protect against early SEC injury that occurred before the onset of HPC injury at 6 h. This observation suggests that SEC injury is not entirely dependent on PMNs in this model. In vitro, MCT caused PMNs to degranulate in a concentration-dependent manner. These results provide evidence that PMNs are critical to the HPC injury caused by MCT/LPS cotreatment and contribute to the progression of SEC injury. 相似文献
35.
Effects of remifentanil on neutrophil adhesion, transmigration, and intercellular adhesion molecule expression 总被引:2,自引:0,他引:2
Hofbauer R Frass M Gmeiner B Sandor N Schumann R Wagner O Kaye AD 《Acta anaesthesiologica Scandinavica》2000,44(10):1232-1237
BACKGROUND: Anaesthetic drugs are used for pain therapy and anaesthesia. Neutrophils play a significant role during the process of inflammation. The aim of the current study was to investigate the effects of remifentanil and fentanyl on neutrophil migration through endothelial cell monolayers, and on adhesion molecule expression. METHODS: After isolation of polymorphonuclear neutrophils (PMNL) we used a currently described migration assay. PMNL and/or endothelial cell monolayers (ECM) were pre-treated with remifentanil using clinically relevant, as well as higher and lower concentrations or relevant concentrations of fentanyl. RESULTS: Concentrations of remifentanil (50 ng/mL) similar to the relevant plasma concentration were able to inhibit PMNL migration through ECM significantly (migration compared to the control 82+/-7% SD; P<0.05), when both cell types were treated with the synthetic narcotic remifentanil. Fentanyl (30 ng/mL) showed a stronger inhibitory effect (migration compared to the control 67+/-9.2%; P<0.05). Endothelial cell adhesion molecule expression was reduced after either remifentanil or fentanyl. CONCLUSION: The results of the present investigation indicate that remifentanil influences interaction of ECM against human neutrophils. Compared to fentanyl, remifentanil seems to exhibit minor inhibitory effects on neutrophil migration. 相似文献
36.
大鼠视网膜缺血再灌注后细胞间粘附分子-1的表达 总被引:3,自引:2,他引:3
目的 探讨大鼠视网膜缺血再灌注后不同时间视网膜细胞间粘附分子 1(inter cellularadhesionmolecule 1,ICAM 1)表达和白细胞浸润的变化。方法 选择健康成年Wistar大鼠 70只 ,随机分成 7组 :正常组和再灌注 0、2、6、12、2 4、4 8h组 ,每组 10只。用眼内灌注法建立视网膜缺血再灌注动物模型。制作大鼠视网膜冰冻及石蜡切片 ,分别作免疫组化SP染色和常规HE染色 ,并对SP染色结果作计算机图像分析。结果 ICAM 1在正常视网膜血管内皮细胞胞膜微量表达 ,缺血 6 0min后 ,ICAM 1表达上调 ,至再灌注2 4h达高峰 ,在再灌注 4 8h仍维持较高水平。再灌注 6h ,视网膜开始有白细胞浸润 ,随再灌注时间延长而增多 ,再灌注 2 4、4 8h组 ,视网膜中发现较多浸润的白细胞。结论 视网膜缺血再灌注早期 ,视网膜血管内皮细胞ICAM 1表达上调 ,继而 ,视网膜中白细胞浸润增多 ,这一过程是视网膜缺血再灌注损伤的重要机制之一。 相似文献
37.
抗中性粒细胞胞浆抗体的检测及意义 总被引:1,自引:0,他引:1
目的探讨检测抗中性粒细胞胞浆抗体(ANCA)与ANCA密切相关疾病中的价值。方法应用间接免疫荧光(IIF)法检测255例相关疾病患者血清ANCA的检出率。结果检测255例相关疾病中,韦格纳氏肉芽肿阳性率为80%;未分类血管炎阳性率为58.62%;系统性红斑狼疮阳性率为69.64%;类风湿性关节炎阳性率为38.10%;上、下呼吸道损害阳性率为36%;肾病综合征阳性率为41.79%;急性肾衰阳性率为38.46%;慢性肾衰阳性率为9.38%;过敏性紫癜阳性率为42.86%。结论检测ANCA判断以韦格纳氏肉芽肿为代表疾病的病情诊断具有参考价值。 相似文献
38.
目的观察补阳还五汤对脑缺血再灌注后中性粒细胞浸润和ICAM-1表达的影响。方法术前7天开始罐胃,然后用线栓法诱导大鼠大脑中动脉阻塞模型,再灌24h后采用神经症状评分和梗死周边区存活神经元数评价脑损伤情况,用髓质过氧化物酶(MPO)和ICAM-1免疫组化方法,评价中性粒细胞浸润和ICAM-1表达情况。结果缺血90min再灌24h后,补阳还五汤能显著改善神经症状(P<0·05或P<0·01),增加缺血半球皮层周边区存活神经元数(P<0·05或P<0·01)。与模型组比较,补阳还五汤显著减少缺血半球皮层MPO阳性细胞数(P<0·01)和ICAM-1阳性血管数(P<0·01)。结论补阳还五汤对脑缺血损伤有保护作用,并能减少中性粒细胞浸润和ICAM-1表达。 相似文献
39.
目的研究雪莲花醇提物(ESLHM)的抗氧化活性。方法用·HO生成系统Fe2+维生素C诱导大鼠心、肝、肾组织匀浆脂质过氧化,用TBA比色法测定MDA含量;用NBT还原法测酵母多糖A刺激大鼠中性粒细胞产生的O2-;用分光光度法测H2O2诱发的大鼠红细胞溶血度。结果对照组大鼠心、肝、肾匀浆经Fe2++维生素C溶液诱发后MDA含量较空白组升高(P<0.01),中性粒细胞受酵母多糖A刺激后O2-生成较空白组升高(P<0.01),红细胞经H2O2诱发后溶血度较空白组升高(P<0.01)。而6.3,12.5,25,50,100,200μ·L-1 ESLHM能不同程度抑制Fe2+维生素C诱导的大鼠心、肝、肾脂质过氧化产物MDA生成,其抑制心、肝、肾MDA生成的IC50分别为29.4,32.9,31.4 μg·L-1,其量效关系均呈负相关,相关系数分别为-0.905, -0.912,-0.908,相关性检验P值均<0.01;能不同程度抑制酵母多糖A刺激中性粒细胞生成O2-,其抑制中性粒细胞生成O2-的IC50为24.6 μg·L-1,其量效关系呈负相关,相关系数为-0.887(P<0 01);能不同程度抑制H2O2诱发的红细胞氧化溶血,其抑制红细胞氧化溶血的IC50为57.6μg·L-1,其量效关系呈负相关,相关系数为-0.905(P<0.01),.结论雪莲花醇提物通过清除·HO,O2-及H2O2发挥抗氧化活性。 相似文献
40.
目的:探讨核苷酸寡聚化结构域样受体家族半胱天冬酶募集结构域蛋白3(nucleotide binding oligomerization domain-like receptor family caspase recruitment domain containing 3,NLRC3)与III期结直肠癌的预后及肿瘤免疫相关指标
的关系。方法:回顾性收集中南大学湘雅医院2012年至2013年122例经手术根治切除的III期结直肠癌患者的相关资
料。利用免疫组织化学法分析NLRC3与CD8+ T细胞的表达情况,利用患者的术前临床资料计算中性粒细胞/淋巴细
胞比值(neutrophil to lymphocyte ratio,NLR),并检测其微卫星稳定性。采用χ2检验分析NLRC3与临床病理因素之间的
关系,采用COX回归模型分析III期结直肠癌的独立预后因素。结果:在III期结直肠癌中,肿瘤组织CD8+ T细胞浸润
分期(χ2=27.79,P<0.01)、NLR值(χ2=6.35,P<0.05)、淋巴结转移分期(χ2=10.12,P<0.01)以及微卫星稳定性(χ2=6.05,
P<0.05)与NLRC3的表达有关。NLRC3(OR=0.066,95% CI:0.020~0.218)、血管癌栓(OR=3.119,95% CI:1.547~6.286)
及NLR(OR=5.103,95% CI:2.465~10.563)对III期结直肠癌的5年总生存期(overall survival,OS)有影响(均P<0.05);另
外,NLRC3(OR=0.144,95% CI:0.055-0.377)、血管癌栓(OR=3.589,95% CI:1.859~6.932)及NLR(OR=2.939,95% CI:
1.509~5.723)对III期结直肠癌的无病生存期(disease free survival,DFS)同样有影响(均P<0.05)。结论:NLRC3,血管癌栓
和NLR是III期结直肠癌的独立预后因素。NLRC3通过抑制系统性炎症、促进局部抗肿瘤免疫而使III期结直肠癌患者
具有良好的预后。 相似文献