透析用水内毒素含量检测数据调查研究分析

目的符合透析治疗安全的透析用水是血液透析日常治疗开展的基本保障,根据统计分析内毒素含量的变化规律,探索控制透析用水内毒素含量的管理方式。方法对上海市21家血液净化中心(室)2019年3月至2020年2月期间透析用水的内毒素(endotoxin,ET)含量数据进行汇总与统计分析。结果透析用水内毒素含量在全年的春季与夏季中会存在部分偏高的情况,其中春季送检的样本中,ET含量>0.25 EU/ml比例占当季送检样本的0.57%,ET含量在0.03~0.25EU/ml之间的比例占7.34%;在夏季送检的样本中,ET含量>0.25EU/ml比例占当季送检样本的1.13%,ET含量在0.03~0.25EU/ml之间的比例占3.39%,与秋冬两季水平相比,差异有统计学意义(F=11.392,P值<0.001)。结论严格管控透析用水生产、输送过程的每个环节,规范采样流程、加强反渗机日常维护管理、重视水处理系统及配管的日常消毒等措施可减少血液透析相关的不良反应发生,提高患者透析质量。     

Clostridium difficile infection as a cause of severe sepsis

Although colitis is often seen in critically ill patients who have received multiple broad-spectrum antibiotics, there are no reports describing severe sepsis as a result ofClostridium difficile infection. We describe three cases of severe sepsis with local intestinalClostridium difficile infection as the only identifiable etiology. The mechanism of severe sepsis may be a derangement of the gastrointestinal barrier function. This could result in absorption of microbes or endotoxin or activation of inflammatory cascades in the submucosa of the intestine or liver.     

Anti-inflammation effects of naloxone involve phosphoinositide 3-kinase delta and gamma

Background

Phosphoinositide 3-kinase (PI3K) delta and gamma (the p110δ and p110γ isoforms of PI3K) actively participate in the process of inflammation. We sought to elucidate the possible roles of PI3Kδ and PI3Kγ in mediating the anti-inflammation effects of naloxone.

Materials and methods

Murine macrophages were treated with endotoxin, endotoxin plus naloxone, or endotoxin plus naloxone plus the PI3K inhibitors (the PI3Kδ inhibitor IC87114, the PI3Kγ inhibitor AS252424, or IC87114 plus AS252424) and denoted as the LPS, LPS + N, LPS + N + IC, LPS + N + AS, and LPS + N + IC + AS group, respectively. Differences in inflammatory molecules and levels of nuclear factor-κB (NF-κB) activation and Akt activation (indicator of PI3K activity) among these groups were compared.

Results

The concentrations of inflammatory molecules (macrophage inflammatory protein 2, tumor necrosis factor-α, interleukin-1β, and cyclooxygenase-2/prostaglandin E₂) and the levels of NF-κB activation (p-NF-κB p65 and p-inhibitor-κB concentrations and NF-κB-DNA binding activity) of the LPS + N group were significantly lower than those of the LPS group (all P < 0.001). These data confirmed the anti-inflammation effects of naloxone. Moreover, the anti-inflammation effects of naloxone could be counteracted by the inhibitors of PI3Kδ and PI3Kγ, as the concentrations of inflammatory molecules and the levels of NF-κB activation of the LPS + N group were significantly lower than those of the LPS + N + IC, LPS + N + AS, and LPS + N + IC + AS groups (all P < 0.05). In contrast, the concentration of phosphorylated Akt of the LPS + N group was significantly higher than those of the LPS, LPS + N + IC, LPS + N + AS, and LPS + N + IC + AS groups (all P < 0.05).

Conclusions

PI3Kδ and PI3Kγ play crucial roles in mediating the anti-inflammation effects of naloxone.     

Immunological aspects of severe bacterial sepsis

In spite of discovery of new antibiotics and regular progress in intensive care, mortality from severe bacterial sepsis remains high. In this review the importance of cellular and humoral immunity in the pathogenesis and the outcome of severe infection is delineated. Immunological evaluation of patients in Intensive Care Units should be performed almost routinely in order to detect high risk patients with acquired defect in host-defence mechanisms. For these patients in addition to nutritional care, passive or active immunotherapy will help to restore resistance to bacterial infection.     

高迁移率族蛋白1参与脓毒症大鼠急性呼吸窘迫综合征时中性粒细胞的凋亡

目的 探究脓毒症大鼠急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)时高迁移率族蛋白1(high mobility group box 1,HMGB1)参与中性粒细胞(polymorphonuclear neutrophils,PMN)凋亡延迟的相关机制及正丁酸钠(sodium butyrate,SB)的干预效果. 方法 采用随机数字表法将90只健康成年雄性Sprague-Dawley(SD)大鼠随机分为正常对照组(NS组,6只)、内毒素(lipopolysaccharide,LPS)致伤组(LPS组,42只)、HMGB1抑制剂SB干预组(SB组,42只),LPS组、SB组又分为7个时相点(LPS致伤后0.5、1、2、6、12、24、48 h),每个时相点6只动物.LPS组,腹腔注射LPS 5 mg/kg;SB组,腹腔注射LPS 5 mg/kg后0.5 h静脉注射SB,每次剂量500 mg/kg;NS组,腹腔注射生理盐水1 ml.LPS组、SB组于LPS注射后各时点,颈静脉取血检查PMN,取血后左肺灌洗收集支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF),取右肺中叶行HMGB1 mRNA检测;于LPS注射12h时点(NS组大鼠留取颈静脉血、收集BALF、取右肺中叶行HMGB1 mRNA检测),3组大鼠收集左肺BALF后,取右肺下叶检测肺组织湿/干重比(wet/dry weight ratio,W/D),取右肺上叶进行病理组织学检查;于24、48 h时点,LPS组、SB组取右肺下叶检测肺组织W/D、取右肺上叶进行病理组织学检查. 结果 与NS组比较,LPS组肺组织中HMGB1 mRNA表达量明显增高,24 h达最大值,差异有统计学意义(P＜0.05);SB组的HMGB1 mRNA表达量减少,差异有统计学意义(P＜0.05).LPS组BALF中凋亡早期PMN表达量与NS组类似,但凋亡晚期PMN变化则不同,LPS组外周血中凋亡晚期PMN细胞高于NS组(P＜0.05),LPS组BALF中凋亡晚期PMN细胞均低于NS组(P＜0.05).LPS 12 h组BALF的PMN百分比明显高于NS组[(49.1±6.8)、(2.7±0.5)],差异有统计学意义(P＜0.01).LPS组肺组织光镜下可见肺泡腔水肿,支气管壁中发现PMN浸润,肺泡壁毛细血管扩充血.LPS24 h组肺组织的W/D明显高于NS组[(6.71±0.12)、(4.18±0.26)],差异有统计学意义(P＜0.05).SB干预组的HMGB1 mRNA表达量减少,早期凋亡率类似,SB组的BALF晚期凋亡率高于同时点LPS组的BALF,SB外周血组晚期凋亡低于同时点LPS外周血组,差异有统计学意义(P＜0.05).SB组BALF的PMN百分比、肺组织病理损伤程度、W/D均低于LPS组,差异有统计学意义(P＜0.05). 结论 在大鼠ARDS中,HMGB1 mRNA表达较晚,但持续时间长,SB对HMGB1有潜在的治疗作用,HMGB1可能参与PMN凋亡机制的调节.     

Increased expression of 78 kD glucose-regulated protein promotes cardiomyocyte apoptosis in a rat model of liver cirrhosis

Aims: This study was to investigate the role and underlying mechanism of 78 kD glucose-regulated protein (GRP78) in cardiomyocyte apoptosis in a rat model of liver cirrhosis. Methods: A rat model of liver cirrhosis was established with multiple pathogenic factors. A total of 42 male SD rats were randomly divided into the liver cirrhosis group and control group. Cardiac structure analysis was performed to assess alterations in cardiac structure. Cardiomyocytes apoptosis was detected by TdT-mediated dUTP nick end labeling method. Expression of GRP78, CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, nuclear factor kappa-light-chain-enhancer of activated B cells p65 subunit (NF-κB p65) and B cell lymphoma-2 (Bcl-2) was detected by immunohistochemical staining. Results: The ratios of left ventricular wall thickness to heart weight and heart weight to body weight were significantly increased with the progression of liver cirrhosis (P < 0.05). Apoptosis index of cardiomyocytes was significantly increased with the progression of liver cirrhosis (P < 0.05). The expression levels of GRP78, CHOP and caspase-12 were significantly increased in the progression of liver cirrhosis (P < 0.05). The expression levels of NF-κB p65 and Bcl-2 were highest in the 4-wk liver cirrhosis, and they were decreased in the 6-wk and 8-wk in the progression of liver cirrhosis. GRP78 expression levels were positively correlated with apoptosis index, CHOP and caspase-12 expression levels (P < 0.05). CHOP expression levels were negatively correlated with NF-κB p65 and Bcl-2 expression levels (P < 0.05). Conclusion: Increased expression of GRP78 promotes cardiomyocyte apoptosis in rats with cirrhotic cardiomyopathy.     

内毒素诱导白血病细胞株HL-60凋亡作用的研究

目的研究革兰氏阴性杆菌内毒素对白血病细胞诱导凋亡作用。方法常规培养急性早幼粒细胞性白血病细胞株HL-60,经不同浓度内毒素作用后,利用流式细胞技术测定白血病细胞的凋亡百分率。结果在孵育到12h出现了凋亡的特征AP波峰,与对照组相比,1μg／mL、5μg／mL、10μg/mL内毒素均有不同程度的诱导凋亡作用,其中以5μg／mL 作用显著。结论细菌内毒素可显著诱导白血病细胞凋亡。     

内毒素对严重烧伤后细胞因子、可溶性粘附分子及sFas/sFasL的影响

目的　探讨内毒素对严重烧伤后细胞因子、可溶性粘附分子及sFas sFasL的影响。方法　选择烧伤总面积 (TBSA) >30 %患者 2 8例 ,健康志愿者 4 0例作为正常对照组。分别于伤后不同时相点 (伤后 1、 3、 5、 7、 14、 2 1、 2 8和 35d)测定患者血中内毒素、细胞因子 (TNF α、IL 1β、IL 6、IL 8、IL 12和IL 18)、可溶性粘附分子 (ICAM 1和VCAM 1)以及sFas sFasL的水平。按内毒素水平将其分为三组 :A组 ,脂多糖 (LPS)为 0～ 0 2 0 0U ml;B组 ,LPS为 0 2 0 0～ 0 4 0 0EU ml;C组 ,LPS >0 4 0 0EU ml。结果　与A组和正常对照组比较 ,B组和C组的TNF α、IL 1β、IL 6、IL 8、IL 18和ICAM 1水平在不同时相点均呈显著性上升 (P <0 0 5～ 0 0 1) ;而B组和C组患者血中VCAM 1和sFas sFasL水平在部分时相点呈升高趋势 ,与正常对照组和A组比较 ,其差异具有显著性意义 (P <0 0 5～ 0 0 1) ;B组和C组患者血中IL 12水平在烧伤早期呈下降的趋势 ,与A组和正常对照组比较 ,其差异具有显著性意义 (P <0 0 5～ 0 0 1) ,但在烧伤中后期则呈上升趋势 ;血浆LPS主要与血清中TNF、IL 1β、IL 6、IL 8、IL 18水平呈显著正相关 (P <0 0 5～0 0 1)。结论　烧伤后内毒素直接或间接影响机体细胞因子、可溶性粘附分子及sFas     

Poly(I:C) source,molecular weight and endotoxin contamination affect dam and prenatal outcomes,implications for models of maternal immune activation

The viral mimetic polyinosinic:polycytidylic acid (poly(I:C)) is increasingly used to induce maternal immune activation (mIA) to model neurodevelopmental disorders (NDDs). Robust and reproducible phenotypes across studies are essential for the generation of models that will enhance our understanding of NDDs and enable the development of improved therapeutic strategies. However, differences in mIA-induced phenotypes using poly(I:C) have been widely observed, and this has prompted the reporting of useful and much needed methodological guidelines. Here, we perform a detailed investigation of molecular weight and endotoxin variations in poly(I:C) procured from two of the most commonly used suppliers, Sigma and InvivoGen. We demonstrate that endotoxin contamination and molecular weight differences in poly(I:C) composition lead to considerable variability in maternal IL-6 response in rats treated on gestational day (GD)15 and impact on fetal outcomes. Specifically, both endotoxin contamination and molecular weight predicted reductions in litter size on GD21. Further, molecular weight predicted a reduction in placental weight at GD21. While fetal body weight at GD21 was not affected by poly(I:C) treatment, male fetal brain weight was significantly reduced by poly(I:C), dependent on supplier. Our data are in agreement with recent reports of the importance of poly(I:C) molecular weight, and extend this work to demonstrate a key role of endotoxin on relevant phenotypic outcomes. We recommend that the source and batch numbers of poly(I:C) used should always be stated and that molecular weight variability and endotoxin contamination should be minimised for more robust mIA modelling.