【作者】 高敏；

【导师】 肖献忠；

【作者基本信息】 中南大学 ， 病理学与病理生理学， 2010， 硕士

【摘要】 脓毒症是感染导致的全身炎症反应综合征(SIRS),是各种严重创伤、烧伤、休克、再灌注损伤及外科大手术后常见的并发症,其死亡率高达30-50%。脓毒症的发生机制极其复杂,其复杂性和非线性的特点导致了对其诊断、预测和治疗的不确定性。这也是当前脓毒症死亡率居高不下的主要原因。因此,研究脓毒症生物标志物,探讨脓毒症诊断、预测、疗效评估的新方法,以指导脓毒症的防治,降低其发病率和死亡率,具有重要的科学意义。本课题采用盲肠结扎穿刺(CLP)制备大鼠脓毒症模型,观察大鼠CLP前后血清炎症介质TNF-α, IL-1β, IL-6,粒细胞-巨噬细胞集落刺激因子(GM-CSF),高迁移率族蛋白1 (HMGB1)和单核细胞趋化蛋白-1(MCP-1)及血尿素氮(BUN),肌酐(Cr),乳酸脱氢酶(LDH),谷丙转氨酶(ALT),谷草转氨酶(AST),肌酸激酶(CK)和血常规的变化,探讨上述指标的改变及其与脓毒症大鼠预后的关系,试图筛选出有意义的指标建立指标集,并采用该指标集对脓毒症大鼠进行预后评估,以改善脓毒症大鼠预后评估的敏感性、特异性和准确度。结果如下：1.大鼠CLP模型复制：大鼠行CLP后,6h开始死亡,12-24h死亡最多,72小时死亡率为59%；血清炎症介质TNF-α, IL-1β, IL-6, GM-CSF及HMGB1水平显著升高；CLP术后12h处死大鼠,发现多个器官(心、肝、肺、脑及肾)发生组织形态学改变。2.根据CLP术后72h是否死亡分为存活组和死亡组。存活组大鼠CLP术后12小时ALT, AST, HMGB1, IL-6以及MCP-1水平高于术前(p<0.05或p<0.01)；白细胞计数、血小板计数、CK及IL-1β水平低于术前(p<0.05或p<0.01)。死亡组大鼠CLP术后12小时体温、红细胞计数、红细胞比积、BUN,ALT,AST,HMGB1,IL6以及MCP1水平高于术前(p<0.05或p<0.01)；白细胞计数、血小板计数、血清肌酸激酶水平低于术前(p<0.05或p<0.01)。3.死亡组CLP术后12小时BUN, Cr, ALT, LDH, CK, IL-6以及MCP-1水平高于存活组(p<0.05或p<0.01)；血小板计数、血清HMGB1及GM-CSF水平低于存活组(p<0.05或p<0.01)。4.CLP术后12小时体温以及血清尿素氮、肌酐、谷丙转氨酶、肌酸激酶、IL-6和MCP-1水平与大鼠存活结局呈负相关,而血小板计数、血清HMGB1及GM-CSF与大鼠存活结局呈正相关。5.为判断各指标在脓毒症预后预测中的价值及选择最优的指标集,采用Logistic回归对上述与脓毒症预后相关的指标进行了分析,发现将尿素氮、肌酐、IL-6.GM-CSF纳入方程,则预测的敏感性(86.2%)、特异性(83.3%)以及准确度(84.7%)均达最高,据此建立下述回归方程：Logit P=-8.367+1.124BUN+1.134Cr+0.003IL6-0.249GM-CSF其中P为死亡与存活概率之比,LogitP为死亡与存活概率之比的自然对数。综上所述,本研究在成功复制了大鼠CLP脓毒症模型基础上,筛选出与大鼠脓毒症预后相关的指标,并选择最优指标集建立了脓毒症预后预测模型。该预测模型显示,脓毒症大鼠血清BUN,Cr,IL-6水平升高及GM-CSF水平降低时预后不良。上述结果为临床脓毒症的预后判断和疗效评估提供了新的实验证据和研究思路。更多还原

【Abstract】 Sepsis is the systemic inflammatory response syndrome (SIRS) induced by infection. It is the common complication of severe trauma, burns, shock, ischemia-reperfusion injury and surgery, and the mortality rate of sepsis is as high as 30-50%. The pathogenesis of sepsis is extremely complicated. Its complexity and nonlinearity lead to the uncertainty of diagnosis, evaluation of prognosis and treatment, which is the main cause of its high mortality. Therefore, to study the biomarkers and find new methods of the diagnosis, prediction, efficacy evaluation of therapies for the guidance of the prevention and treatment, decrease of the morbidity and mortality are of great importance in sepsis.In this study, a sepsis model was made by cecal ligation and puncture (CLP) in rats. The serum levels of inflammatory mediators (TNF-α, IL-1β, IL-6, GM-CSF, HMGB1, MCP-1), BUN, Cr, LDH, ALT, AST, CK and blood routine were detected pre-or post-CLP. The correlation between the changes of these indexes and the outcome of rats were analyzed, the appropriate index set were selected for the assessment of the prognosis of sepsis, with the aims to improve the sensitivity, specificity and accuracy of prognosis evaluation of sepsis. The results were as follows:1. A sepsis model was successfully established by CLP in rats:rats died from 6h post-CLP, the mortality rate was 59%; the serum levels of inflammatory mediators (TNFα, IL-1β, IL-6, GM-CSF, HMGB1) were significantly increased post-CLP; morphological changes were observed in multiple organs at 12h post-CLP, including heart, liver, lung, kidney and brain.2. According to the outcome at 72h post-CLP, the rats were divided into the survival group and non-survival group. In survival group, the serum levels of ALT, AST, HMGB1, IL-6 and MCP-1 were significantly higher at 12 hour post-CLP, compared with pre-CLP (p <0.05 or p<0.01); the white blood cell count, platelet count and serum CK, and IL-1βwere significantly lower at 12 hour post-CLP compared with pre-CLP (p<0.05 or p<0.01). In non-survival group, the body temperature, red blood cell count, hematocrit, serum BUN, ALT, AST, HMGB1, IL-6 and MCP-1 were significantly higher at 12 hour post-CLP compared with pre-CLP (p<0.05 or p<0.01); the white blood count, platelet count, serum CK were significantly lower at 12 hour post-CLP compared with pre-CLP (p<0.05 or p<0.01).3. The serum levels of BUN, Cr, LDH, ALT, CK, IL-6 and MCP-1 were significantly higher in non-survivors compared with survivors (p<0.05 or p<0.01); the platelet count and serum levels of HMGB1 and GM-CSF at 12 hour post-CLP were significantly lower in non-survivors compared with survivors (p<0.05 or p<0.01)4. The body temperature, BUN, Cr, ALT, CK, IL-6 and MCP-1 levels at 12h post-CLP were negatively correlated with rat survival outcome; while the platelet count, HMGB1 and GM-CSF at 12h post-CLP were positively correlated with survival outcome in rats.5. To evaluate the significance of each index and choose the best set of indexes for the prediction of prognosis of sepsis, Logistic regression was used to analyze the above indexes which correlated with sepsis prognosis and it was found that when BUN, Cr, IL-6, GM-CSF were selected into the equation, the predict sensitivity (86.2%), specificity (83.3%) and accuracy (84.7%) of prediction reached the maximum. The regression equation was as follows: Logit P=-8.367+1.124 BUN+1.134Cr+0.003 IL-6-0.249GM-CSF P is the ratio of the probability of non-survival and survival and Logit P is the natural logarithm of P.In summary, in this study a optimal index set was selected for the prediction of prognosis in sepsis by using a CLP model in rats and a prediction model with the best index set was established. It was shown by the prediction model that a poor prognosis in sepsis was associated with a high serum level of BUN, Cr and IL-6 and a low serum level of GM-CSF. These results provided new experimental evidences and research ideas for the prognosis prediction and efficacy evaluation of therapies in sepsis.更多还原