Experimental human endotoxemia enhances brain activity during social cognition

Acute peripheral inflammation with corresponding increases in peripheral cytokines affects neuropsychological functions and induces depression-like symptoms. However, possible effects of increased immune responses on social cognition remain unknown. Therefore, this study investigated the effects of experimentally induced acute inflammation on performance and neural responses during a social cognition task assessing Theory of Mind (ToM) ability. In this double-blind randomized crossover functional magnetic resonance imaging study, 18 healthy right-handed male volunteers received an injection of bacterial lipopolysaccharide (LPS; 0.4 ng/kg) or saline, respectively. Plasma levels of pro- and anti-inflammatory cytokines as well as mood ratings were analyzed together with brain activation during a validated ToM task (i.e. Reading the Mind in the Eyes Test). LPS administration induced pronounced transient increases in pro- (IL-6, TNF-α) and anti-inflammatory (IL-10, IL-1ra) cytokines as well as decreases in mood. Social cognition performance was not affected by acute inflammation. However, altered neural activity was observed during the ToM task after LPS administration, reflected by increased responses in the fusiform gyrus, temporo-parietal junction, superior temporal gyrus and precuneus. The increased task-related neural responses in the LPS condition may reflect a compensatory strategy or a greater social cognitive processing as a function of sickness.     

Tempol 对肝硬化大鼠肝门阻断后肠道菌群移位及内毒素血症的作用

目的：探讨4-羟基-2,2,6,6-四甲基哌啶（Tempol）对肝硬化大鼠肝门阻断后肠道细菌移位和内毒素血症的作用。方法选择SD大鼠30只,采用四氯化碳诱导行肝硬化建模,将建模大鼠随机均分为假手术组（不阻断肝门）、对照组（阻断肝门）、实验组（阻断肝门前后静注Tempol ）。3组均取门静脉、腔静脉血检测血清内毒素,取肠系膜淋巴结、肝组织、肺组织行细菌培养,以及小肠黏膜形态与细胞凋亡检测。结果与假手术组及对照组比较,实验组可明显减少肝门阻断后的肠道细菌移位及血清内毒素水平（ P均＜0．05）。结论 Tempo1可有效地预防肝硬化大鼠肝门阻断后的肠道细菌移位和内毒素血症。     

新生儿感染相关性胆汁淤积症血清内毒素检测及其临床意义

目的：分析感染相关性胆汁淤积症新生儿患儿血清内毒素水平及临床意义.方法：对42例诊断为感染相关性胆汁淤积症的新生儿进行内毒素测定,比较治疗前及病情好转后血清内毒素水平变化情况;同时以30例明确存在感染但未出现胆汁淤积的新生儿作为对照组,比较两组之间内毒素水平差异.结果：胆汁淤积症患儿治疗前血清内毒素水平为（28.25±9.08） pg/ml,明显高于对照组（9.33±2.05） pg/ml,（P＜0.05）,而治疗好转后血清内毒素水平为（10.32±3.21） pg/ml,明显低于治疗前（P＜0.05）.血渍内毒素水平与肝功能指标间呈线性关系,回归系数具有统计学意义（P＜0.05）.早产儿及低出生体重儿更容易出现感染相关性胆汁淤积症.结论：内毒素是导致新生儿感染相关性胆汁淤积的重要因素之一.进行抗内毒素治疗,可以缩短病程改善预后,具有重要的临床意义.     

Using intestinal flora to distinguish non-alcoholic steatohepatitis from non-alcoholic fatty liver

ObjectiveTo explore specific flora in mouse models of non-alcoholic steatohepatitis (NASH) to improve NASH diagnostic protocols.MethodsSixty mice were divided into normal diet (ND, 20 mice) and high-fat/high-sugar diet (HFSD) groups (40 mice). After 8 weeks of feeding, 10 mice in the ND group and 20 mice in the HFSD group were sacrificed to create the short-term ND and non-alcoholic fatty liver (NAFL) groups, respectively. After 16 weeks of feeding, the remaining mice were sacrificed to create the long-term ND and NASH groups, respectively. We then examined fecal flora, serum biochemical indices, and lipopolysaccharide and tumor necrosis factor-α levels and analyzed liver tissue.ResultsThe relative abundance of Lactobacillus, Desulfovibrio, Ruminiclostridium 9, and Turicibacter differed between NASH and NAFL mice, and the areas under the receiver operating characteristic curve of the four genera for diagnosing NASH were 0.705, 0.734, 0.737, and 0.937. The non-alcoholic fatty liver disease activity score was positively correlated with the relative abundance of Desulfovibrio (r = 0.353), Ruminiclostridium 9 (r = 0.431), and Turicibacter (r = 0.688).ConclusionsThe relative abundance of Lactobacillus, Desulfovibrio, Ruminiclostridium, and Turicibacter may help distinguish NASH from NAFL.     

正常淋巴液对内毒素休克小鼠内毒素增敏系统的作用

目的:观察正常肠淋巴液对内毒素休克小鼠内毒素增敏系统的作用,探讨正常淋巴液干预内毒素休克小鼠器官损伤的作用机制。方法:36只SPF级BALC/c雄性小鼠18只采用常规方法引流正常肠淋巴液,另外18只分为假休克组(SS组)、内毒素休克模型组(ES组)和肠淋巴液干预组(NML+ES组),每组6只。后两组应用腹腔注射脂多糖(LPS,35mg/Kg)方法复制小鼠ES模型;60min后,NML+ES组小鼠经股动脉注射正常肠淋巴液(全血量的1/15);6h后摘取各组小鼠的肝、心肌和肺组织,制备组织匀浆,采用ELISA检测脂多糖结合蛋白(LBP)、脂多糖受体(CD14)、肿瘤坏死因子(TNF-α)和白介素6(IL-6)含量。结果:ES组肺、肝、心肌匀浆的LBP、CD14、TNF-α、IL-6含量均显著高于SS组(P0.05);NML+ES组肺组织LBP和TNF-α、肝组织TNF-α和IL-6以及心肌组织LBP、CD14、TNF-α、IL-6含量均较ES组明显降低(P0.05),但肝组织CD14及TNF-α、心肌组织CD14仍高于SS组。结论:正常肠淋巴液可降低内毒素休克小鼠肺、心肌组织内毒素增敏系统的LBP、CD14水平,从而降低炎症反应。     

Endotoxin exposure-response in a fiberglass manufacturing facility

Peak expiratory flow (PEF) and workplace exposure to endotoxin, phenolic resin, and formaldehyde were measured to investigate asthma symptoms and medication use among employees in a fiberglass wool manufacturing plant. Self-recorded PEF was obtained from 37 workers, for a total of 181 days off work and 187 days at work with concurrent personal exposure monitoring. Pre- and post-shift spirometry were obtained on at least 2 days. The 8 hr time-weighted average personal exposure ranges were endotoxin, 0.4–759 ng/m³; phenolic resin, 5.7–327 μg/m³; and formaldehyde, 1.2–265 μg/m³. Amplitude percent mean peak flow was associated with years since starting regular work in the highest endotoxin exposure area, although current assignment in that area was associated with reduced amplitude—evidence for a healthy worker effect. Exposure-response was analyzed by regression of lung function change on exposure using generalized estimating equations with robust variance estimates. Endotoxin exposure above 4 ng/m³ (8 hr time-weighted average) was associated with a decline in lung function across the work shift, and with drops in lung function 16–20 hr after exposure. Phenolic resin exposure was not consistently associated with decrements, and formaldehyde was not associated with decrements in lung function. © 1996 Wiley-Liss, Inc.     

内毒素预处理对大鼠全脑缺血/再灌注后炎性反应影响的实验研究

目的探讨内毒素预处理对大鼠全脑缺血/再灌注后炎性细胞因子的影响及意义.方法采用大鼠全脑缺血/再灌注模型,动态观察内毒素预处理对脑组织髓过氧化物酶(MPO)、肿瘤坏死因子(TNF-α)、白细胞介素1-β(L-1β)活性的影响及海马CA1区神经元计数的变化.结果内毒素预处理后脑组织MPO、TNF-α、IL-1 β活性显著降低,海马CA1区神经元计数下降幅度减少.结论内毒素预处理减轻了全脑缺血/再灌注后的炎性反应,对海马神经有明显保护作用.     

在线血液透析滤过液中细菌内毒素定量法研究

目的 应用动态比浊法鲎实验定量测定血液透析滤过液中的细菌内毒素含量。方法对血液透析滤过液中定量添加标准内毒素进行干扰预试验,将血液透析滤过液原液及稀释成5、10、20倍液,定量添加标准内毒素,其回收率分别为58．17％、106．7％、99．00％和98．79％;从中筛选出最佳的稀释倍数为10倍,进行3个批号血液透析滤过液（040408、040511、040527）正式干扰试验,血液透析滤过液中定量添加标准内毒素,其回收率分别为76．32％、99．00％和96．24％。结果 标准内毒素使用1．00、0．125、0．0156Eu／ml,将血液透析滤过液稀释成10倍,滤过液中定量添加标准内毒素,回收率均为50％-200％,认为血液透析滤过液对试验无干扰作用,可用于样品检查。结论 动态比浊法可以测定血液透析滤过液的细菌内毒素含量。     

重肝内毒素血症发生机制与证治浅述

重肝内毒素血症病机为"毒"和"瘀"。内毒素可激活各种炎性因子,导致全身炎症反应要充分重视内毒素血症危害,及时处理"毒"瘀"病理因素,减少肠源性内毒素的产生和吸收,达到清除内毒素的目的。     

黄芩苷降解细菌内毒素的定量分析测定

目的比较不同浓度黄芩苷降解内毒素的作用。方法采用连续倍比稀释的方法,依次选取6.250、3.125、1.562、0.781 μg/mL黄芩苷溶液,分别与1 EU/mL内毒素工作标准品混合,分别于（37±1）℃恒温水浴15、30、60 min,应用鲎实验检测反应液中内毒素含量。结果6.250 μg/mL黄芩苷对1 EU/mL的细菌内毒素的降解作用最强,15 min内完全降解。3.125、1.562 μg/mL黄芩苷分别在30 min和60 min内完全降解。在同一时间段内,4种不同浓度的黄芩苷降解内毒素的作用依次减弱。结论黄芩苷降解内毒素的作用有浓度依赖性和时间依赖性,随黄芩苷浓度升高,降解内毒素作用逐渐增强;随作用时间延长,黄芩苷降解内毒素作用增强。该结果提示黄芩苷有较好的降解细菌内毒素的作用。