缬沙坦和培哚普利对大鼠肝纤维化模型肠通透性的影响

目的 观察血管紧张素受体阻滞剂缬沙坦和血管紧张素转换酶抑制剂培哚普利对四氯化碳诱导大鼠肝纤维化模型的疗效及对其肠通透性的影响。方法 将大鼠分为A组(正常对照组)、B组(模型对照组)、C组(缬沙坦治疗组)和D组(培哚普利治疗组)，于造模第4周C组开始用缬沙坦(10mg／kg)，D组开始用培哚普利(0.5mg／kg)治疗，共4周，进行肝组织及小肠组织苏木精-伊红染包，检测血浆D乳酸、DAO和内毒素浓度。结果经治疗后肝纤维化大鼠肝小叶结构趋于正常，纤维间隔变薄，血浆D-乳酸、DAO和内毒素浓度下降。结论 培哚普利和缬沙坦能有效地减轻四氯化碳诱导肝纤维化大鼠的损伤及纤维化程度，减轻肠源性内毒素血症和肠通透性增加。     

肿瘤坏死因子及磷脂酶A2与实验性急性肝衰竭

目的：为探讨肿瘤坏死因子（ＴＮＦ）及磷脂酶Ａ＿２（ＰＬＡ＿２）在急性肝衰竭（ＡＨＦ）时的作用及关系。方法：用Ｄ－氨基半乳糖及内毒素复制急性肝衰竭动物模型，检测其血清中ＴＮＦ含量及肝组织匀浆中ＰＬＡ、活性。结果：ＡＨＦ组鼠血清中ＴＮＦ含量及肝组织匀浆中ＰＬＡ＿２活性明显高于正常对照组（Ｐ值＜０．０５，Ｐ值＜０．０１），ＰＬＡ＿２活性与ＴＮＦ含量呈正相关关系。结论：ＴＮＦ可能激活ＰＬＡ＿２，后者与ＴＮＦ所致的肝损伤有关。     

2010—2013年潍坊市医院透析用水与透析液微生物污染状况调查

目的了解2010—2013年潍坊市医院透析用水和透析液微生物污染状况,为保障血液透析安全和医院感染控制提供理论依据。方法以透析机反渗水输水管末端透析用水与透析器出口透析液为样本,对潍坊市2010年15家、2011年20家、2012年22家、2013年24家医疗机构展开每年一次的定期监测。对样本采用鲎试剂检测法测定内毒素含量,采用营养琼脂倾注平板法测定菌落总数。计数资料采用χ2检验,P0.05为差异有统计学意义。结果 2010—2013年共检测透析用水81份,总合格率为91.4%,逐年合格率分别为100.0%、95.0%、77.3%、95.8%。其中2012年合格率最低,各年比较差异有统计学意义(P0.05)。共检测透析液81份,总合格率为93.8%,逐年合格率分别为100.0%、95.0%、81.8%、100.0%。其中2012年合格率最低,各年比较差异有统计学意义(P0.05)。2010—2013共检测全市5家市级医院、19家县级医院透析用水和透析液162份,其中市级医院合格率为100.0%,县级医院总合格率为88.7%,其差异有统计学意义(χ2=6.847,P0.05)。结论 2010—2013年潍坊市部分医院透析用水和透析液微生物指标存在不合格现象,县级医院问题突出,建议相关部门加强监督管理,保障血液透析安全。     

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.     

Human endothelial cell-based assay for endotoxin as sensitive as the conventional Limulus Amebocyte Lysate assay

Endotoxin, also known as lipopolysaccharide (LPS) produced by bacteria can be present in any liquid or on any biomaterial even if the material is sterile. Endotoxin in mammals can cause fever, inflammation, cell and tissue damage and irreversible septic shock and death. In the body, endothelial cells making up the blood vasculature and endothelial cells in vitro rapidly react to minute amounts of endotoxin resulting in a rapid induction of the cell adhesion molecule E-selectin. In this study we have used immunofluorescent staining to evaluate the expression of E-selectin on human microvascular endothelial cells from the skin (HDMEC) and human umbilical vein endothelial cells (HUVEC) exposed to various concentrations of LPS. In addition, the sensitivity of detection was compared with the most widely used assay for the presence of endotoxin, the Limulus Amebocyte Lysate assay (LAL). The detection of E-selectin on endothelial cells in the presence of LPS for 4 h was found to be at least as sensitive in detecting the same concentration using the LAL assay. A cell adhesion molecule-enzyme immunosorbent assay was also developed and used to quantify LPS using the endothelial cell model. A comparison of LAL and the immunofluorescent staining method was carried out with solutions, nanoparticles, biomaterial extracts and endothelial cells grown directly on biomaterials. Under all conditions, the endothelial/E-selectin model system was positive for the test samples that were positive by LAL. Thus, we propose the use of this highly sensitive, rapid, reproducible assay for the routine testing of endotoxin in all steps in the manufacturing process of materials destined for use in humans. This can give a rapid feedback and localization of bacterial contamination sources with the LAL being reserved for the testing of the final product.     

The role of Kupffer cells in hepatic diseases

Kupffer cells (KCs) constitute 80–90% of the tissue macrophages present in the body. Essential to innate and adaptive immunity, KCs are responsible for the swift containment and clearance of exogenous particulates and immunoreactive materials which are perceived as foreign and harmful to the body. Similar to other macrophages, KCs also sense endogenous molecular signals that may result from perturbed homeostasis of the host. KCs have been implicated in host defense and the pathogenesis of various hepatic diseases, including endotoxin tolerance, liver transplantation, nonalcoholic fatty liver disease, and alcoholic liver disease. In this review, we summarized some novel findings associated with the role of KCs in hepatic diseases, such as the origin and mechanisms KCs polarization, molecular basis for caspase-1 activation called “non-canonical inflammasome pathway” involving the cleavage of Gsdmd by caspase-11, the important role of microRNA in liver transplantation, and so on. A better understanding of KCs biological characteristics and immunologic function in liver homeostasis and pathology may pave the way to investigate new diagnostic and therapeutic approaches for hepatic diseases.     

NF-κB诱骗寡核苷酸对内毒素性肝损伤的保护作用和机制

目的探讨NF-κB诱骗寡脱氧核苷酸对大鼠内毒素性肝损伤的保护作用及其机制。方法60只SD大鼠随机分为对照组、内毒素(LPS)组、诱骗寡核苷酸(decoy ODNs)处理组。取各组大鼠肝组织检测NF-κB蛋白结合活性(EMSA),观察组织病理学改变(光镜)及肝细胞凋亡(TUNEL)。取静脉血检测AST(自动生化仪)以及TNF-α,IL-6的表达水平(ELISA)。结果与对照组相比,内毒素组NF-κB活性明显升高,诱发大量肝细胞凋亡,肝脏损伤明显;同时血清AST,TNF-α及IL-6明显升高(P0.01)。与内毒素组相比,NF-κB诱骗寡核苷酸处理组NF-κB活性受抑制(P0.01)、肝脏组织病理学改变和肝细胞凋亡明显减轻,血清中TNF-α和AST表达水平降低(P0.01),但IL-6表达与内毒素组差异无统计学意义(P0.05)。结论NF-κB诱骗策略能高效抑制NF-κB的活性,抑制其下游有害细胞因子的产生,从而减轻内毒素性肝损伤。     

Intrinsic functional connectivity of insular cortex and symptoms of sickness during acute experimental inflammation

Task-based fMRI has been used to study the effects of experimental inflammation on the human brain, but it remains unknown whether intrinsic connectivity in the brain at rest changes during a sickness response. Here, we investigated the effect of experimental inflammation on connectivity between areas relevant for monitoring of bodily states, motivation, and subjective symptoms of sickness. In a double-blind randomized controlled experiment, 52 healthy volunteers were injected with 0.6 ng/kg LPS (lipopolysaccharide) or placebo, and participated in a resting state fMRI experiment after approximately 2 h 45 min. Resting state fMRI data were available from 48 participants, of which 28 received LPS and 20 received placebo. Bilateral anterior and bilateral posterior insula sections were used as seed regions and connectivity with bilateral orbitofrontal and cingulate (anterior and middle) cortices was investigated. Back pain, headache and global sickness increased significantly after as compared to before LPS, while a non-significant trend was shown for increased nausea. Compared to placebo, LPS was followed by increased connectivity between left anterior insula and left midcingulate cortex. This connectivity was significantly correlated to increase in back pain after LPS and tended to be related to increased global sickness, but was not related to increased headache or nausea. LPS did not affect the connectivity from other insular seeds. In conclusion, the finding of increased functional connectivity between left anterior insula and middle cingulate cortex suggests a potential neurophysiological mechanism that can be further tested to understand the subjective feeling of malaise and discomfort during a sickness response.     

头孢他啶诱导内毒素释放及清开灵注射液抗内毒素作用的体外试验研究

目的:探讨头孢他啶对大肠埃希菌内毒素释放的影响因素及清开灵注射液体外抗内毒素活性。方法:采用二倍稀释法测定头孢他啶对大肠埃希菌的最小抑菌浓度(MIC),确定不同浓度的清开灵注射液对MIC的影响;观察2、10、50、250×MIC头孢他啶对处于对数生长期不同浓度大肠埃希菌产生内毒素的影响及125倍、250倍、500倍稀释的清开灵注射液与头孢他啶联合应用后的抗内毒素作用。结果:头孢他啶对大肠埃希菌的MIC为0.125μg·mL-1,清开灵注射液各稀释浓度对此值无影响。在较高菌浓度时,头孢他啶在杀菌的同时可诱导产生大量内毒素;在较低菌浓度时,各浓度头孢他啶抑制内毒素释放。清开灵注射液可显著对抗内毒素的产生,但无剂量依赖性。结论:头孢他啶对大肠埃希菌内毒素产生的影响与二者的浓度有关,清开灵注射液具有一定的抗内毒素作用。     

CD14在胆道阻塞所致继发性肝损伤中的作用

目的研究胆总管阻塞小鼠肝脏CD14表达的变化及其影响。方法应用小鼠胆总管阻塞模型,观察胆总管阻塞7、14、28d后血浆内毒素水平(LPS)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、肝组织肿瘤坏死因子(TNF)-α及肝脏CD14表达。结果胆总管阻塞7、14、28d后小鼠出现明显的肝损害,表现为ALT、AST、LPS水平、肝组织TNF-α的增高,肝组织CD14表达水平随着阻塞时间的延长而逐渐增高。结论胆道阻塞后小鼠发生了肠源性内毒素血症(IETM)及肝损害,肝组织CD14表达水平显著升高并发挥了重要的作用。