肠源性内毒素血症在硫代乙酰胺所致肝损伤发病中的作用

目的探讨肠源性内毒素血症在硫代乙酰胺（thioacetamide,TAA）所致肝损伤模型发病机制中的地位和作用。方法选用雄性Wistar大鼠26只,随机分为4组,即正常组（N）及结肠切除（C）对照组;TAA损伤组（T）和结肠切除+TAA组（C+T）。采用生化检测法测定血浆内毒素含量和ALT活性。结果单纯给予TAA组,血浆内毒素水平和ALT活性显著高于其它三个组;而结肠切除+TAA组的血浆内毒素水平与结肠切除对照组和正常对照组相比无明显升高,ALT活性结肠切除组+TAA组和正常对照组比较明显升高,但比TAA组却明显减低。T组与C+T组血浆内毒素水平与ALT活性变化之间呈正相关关系（r＝0.985,P＜0.01）。结论TAA所导致的内毒素血症是肠源性内毒素血症;TAA本身有直接致肝细胞损伤的作用,但其所形成的肠源性内毒素血症造成的肝损伤更为严重。     

Changes in biologic markers of oxidative stress and plasma endotoxin levels in gynecologic cancer patients treated with pelvic radiotherapy: a pilot study

Objective

We conducted a pilot study to evaluate the effects of pelvic radiotherapy on biologic markers of oxidative stress and plasma endotoxin levels, and to assess the relationship between the changes of such factors and radiotherapy-related complications.

Methods

Twelve gynecologic cancer patients who were treated via pelvic radiotherapy with or without concurrent chemotherapy were enrolled in this study. Biologic markers of oxidative stress, such as glutathione (GSH) and oxidized glutathione (GSSG), as well as endotoxin levels, were measured weekly during treatment. Subjective symptoms were assessed using the Korean version of the EORTC QLQ-C30 at the baseline and on the 5th week of radiotherapy.

Results

No changes were noted in the level of GSH in whole blood, but the GSH/GSSG ratio was reduced dramatically after the initiation of radiotherapy. The mean plasma endotoxin for all patients tended to increase and persisted during radiotherapy, and the number of patients who evidenced clinically significant endotoxin levels (defined as >0.005 EU/mL) also increased. Nausea/vomiting and diarrhea were significantly changed (p=0.019 and p<0.001, respectively). A significant relationship was noted to exist between the changes in the endotoxin level and nausea/vomiting (p=0.001). However, such symptoms did not correlate with the changes of oxidative stress markers.

Conclusion

Pelvic radiotherapy oxidized the GSH redox system and increased plasma endotoxin. Further investigations containing interventional and longitudinal studies will be required to assess the effects of the changes in oxidative stress markers and endotoxin on radiotherapy-related adverse events.     

肠内免疫微生态营养对重症急性胰腺炎全身炎性反应及预后的影响

目的 探讨肠内免疫微生态营养对重症急性胰腺炎(SAP)全身炎性反应及预后的影响.方法 57例SAP患者在人院48 h内采用随机数字表法被随机分为肠外营养组(PN组)28例和肠内免疫微生态营养组(EIN组)29例,分别进行相应的营养支持7d.入院时及营养后1、3、5、7 d分别检测外周血内毒素、TNF-α、IL-1β、IL-6、IL-10及单核细胞NF-κB活性,并统计两组治疗结果.结果 入院时EIN组内毒素、TNF-α、IL-1β、IL-6、IL-10及单核细胞NF-κB活性与PN组比较差异无统计学意义;营养后7 d,EIN组内毒素、TNF-α、IL-1β、IL-6、IL-10及单核细胞NF-κB活性分别为(2.70±O.13)ng/L、(30.13 4±8.12)ng,L、(20.17±8.04)ng,L、(36.43±8.24)ng,L、(86.45 ±14.54)ng/L、(70.4±3.2)%,均较PN组的(3.25±0.32)ndL、(313.42±144.35)ng/L、(155.29±32.78)ng/L、(324.15±31.47)ng/L、(472.72±48.55)ng/L、(88.4±5.3)%明显下降(P<0.05或<0.01).结论 早期肠内免疫微生态营养能有效减轻内毒素血症,减低NF-κB活性及细胞因子浓度,维持促抗炎反应平衡,改善患者病情及预后.     

清开灵对内毒素性发热家兔下丘脑cAMP及腹中隔区AVP含量的影响

目的:探讨清开灵(QKL)注射液的解热机制。方法:建立家兔内毒素(ET)性发热模型,观察清开灵对家兔体温的影响和用放免法检测下丘脑cAMP及腹中隔区AVP含量的变化。结果:①ET组的△T为(1.68±0.46)℃、TRI₆为29.59±10.39、下丘脑cAMP含量为(2.90±0.40)nmol/g、腹中隔区AVP含量为(47.32±3.77)ng/g,分别显著高于NS组的△T、TRI₆(-0.15±4.29)、下丘脑cAMP含量,腹中隔区AVP含量及QKL+ET组的△T、TRI₆(13.71±3.29)、下丘脑cAMP含量、腹中隔区AVP含量(P＜0.01)。②四组下丘脑cAMP含量变化与体温变化呈明显正相关(r=0.904,P＜0.01)。结论:清开灵的解热机制可能是通过抑制下丘脑cAMP生成,同时通过腹中隔AVP而发挥作用。     

内毒素血症在肝癌发生发展中的作用

目的:探讨内毒素血症在肝癌发生发展中作用。方法:利用饮水中加入0.03%TAA,4个月形成肝硬化,6个月形成肝癌动物的模型。TAA+LPS组从第5个月开始皮下注射内毒素,至实验结束。在肝癌发生发展过程中进行血浆内毒素水平、γ-GT活性、DNA指数、增殖指数,并对N-ras、p53基因点突变进行分析。结果:内毒素可增加bcl-2与p53蛋白过度表达与增加N-ras、p53基因的点突变,增加自由基生成与降低抗氧化酶活性,加重DNA损伤。结论:内毒素能够促进TAA诱发肝癌变的过程。     

肠源性内毒素血症所致肝微循环障碍在肝损伤中的作用

目的　探讨肠源性内毒素血症诱导的肝微循环障碍在肝损伤中的作用。方法　用硫代乙酰胺(TAA)构建肠源性内毒素血症大鼠模型。25只雄性Wistar大鼠分为4组生理盐水组,肝素对照组,TAA组,TAA+肝素组。采用生化检测方法　、组织化学方法　和电镜技术,检测实验各组血浆内毒素、丙氨酸转氨酶(ALT)和丙二醛(MDA)水平的变化及肝组织形态学改变。结果　TAA组血浆内毒素为(0.1899±0.0540)EU/ml、ALT为(1006.80±9182)U/L、MDA为(636±1.96)nmol/ml;对照组分别为(0.0911±0.0068)EU/ml、(31.15±10.58)U/L、(366±0.86)nmol/ml,两组相比TAA组明显升高(P<0.05);TAA+肝素组与TAA组相比,内毒素(0.1597±0.0357)略有下降(P＞005),ALT(586.69±221.97)和MDA(3.64±0.95)显著降低(P＜005)。肝组织形态学改变,苏木精-伊红染色显示TAA组肝坏死面积达50%,纤维素染色TAA组肝窦及微血管内可见大量蓝色丝状团块样的微血栓;电镜结果　显示TAA组窦腔内红细胞聚集、白细胞粘附贴壁,肝窦内皮细胞窗孔数目减少,而TAA+肝素组上述改变明显减轻。结论　肠源性内毒素血症可诱导肝微循环障碍导致缺血、缺氧性肝损伤,肝素可明显改善肠源性内毒素血症所致的肝微循环障碍,从而使缺血、缺氧所致的肝损伤明显减轻。     

一种制备医药用高纯水的新方法

目的 清除水中细菌内毒素、细菌、颗粒、总有机碳及二氧化硅,以提高医药用水质量。方法 用双级反渗透复合膜进行反渗透脱盐和消除水中细菌内毒素,用连续电渗法去离子以脱盐;用双级反渗透加185nm紫外线照射以降低总有机碳,以带正电荷的膜过滤去除细菌;用以上方法可去除或降低水中细菌内毒素、细菌、颗粒、总有机碳及SiO2。并与其他制水方法进行对比。结果 细菌内毒素含量＜0．03EU／ml, 细菌0个／ml,颗粒0个／ml(直径＞0．5μm）,总有机碳＜5μg/L。结论 用该系统制备的高纯医药用水的水质,经测试全部符合国内外药典规定的医药用水标准。     

Analyse des risques et validation du procédé de production du liquide de substitution de la technique d’hémodiafiltration en ligne

IntroductionOnline hemodiafiltration is a technique of dialysis with many advantages, but its use is limited because of the lack of control of microbiological risks. This work conducts a risk analysis of the process for producing substitution liquid for online hemodiafiltration and validates this process from a microbiological point of view.Material and methodThe risk analysis was carried out following the approach of analysing failure modes, their effects and their criticalities. It identified the “worst case” of the production process being studied. For the validation of this process, we used the limulus amoebocytes lysate assay for bacterial endotoxins and the membrane filtration test for sterility control.ResultsWe identified 17 failure modes, 13 of which were acceptable. Failure modes that exceeded the acceptability threshold were defined as “worst cases”. Sterility monitoring and endotoxin testing, conducted in the “worst case”, verified the microbiological quality of the liquid produced to the required standards and subsequently validated the process used.DiscussionThis approach has resulted in the identification of as many failure modes as possible. Validating in “worst case” is an extreme challenge to the process and its success provides a sufficient basis to conclude that the technique is safe and, therefore, to validate the process.ConclusionThis work has enabled us to validate our production process in extreme cases to promote safer use of the technique.     

Toll样受体4在D-氨基半乳糖/内毒素介导的急性肝损伤中的表达

目的研究D-氨基半乳糖(D-Gal)/内毒素介导的急性肝损伤模型中肝组织细胞Toll样受体4(TLR4)的表达变化,探讨TLR4在识别内毒素、启动炎性肝损伤中的作用.方法 BALB/C小鼠腹内注射D-Gal 900 mg/kg与内毒素(即脂多糖,LPS)10 μg/kg后0～7 h分别检测血清丙氨酸转氨酶(ALT)及天门冬氨酸转氨酶(AST)与血浆肿瘤坏死因子(TNF-α)含量以评价肝功能;另随机取10只小鼠给药后观察致死率.用半定量逆转录-聚合酶链反应(RT-PCR)和Tanon Gis 2.0软件分析不同时间点肝组织中TLR4 mRNA表达,并与血浆TNF-α含量进行相关分析;免疫组织化学观察肝组织TLR4蛋白的表达.实验数据用SAS软件分析.结果给药后4 h,血清转氨酶明显升高(与0h比较,P＜0.05);血浆TNF-α含量逐步上升,在2 h、5 h有两个分泌高峰;7 h小鼠开始死亡,10 h致死率达80%.正常小鼠肝组织少量表达TLR4 mRNA,给药后表达明显增强(与0 h比较,P＜0.05);免疫组织化学也显示TLR4蛋白有类似的变化,尤其肝窦内皮细胞、库普弗细胞表达更为显著.血浆TNF-α含量与肝组织TLR4 mRNA表达呈正相关.结论肝内细胞膜上表达的TLR4可能通过启动下游的炎性应答基因表达及细胞因子释放而诱导出肝组织对LPS的炎性应答.因此,调控TLR4表达可能是感染性疾病防治的一种新策略.     

中度低温对内毒素性急性呼吸窘迫综合征大鼠肺细胞因子表达的影响

目的 研究中度低温对内毒素性急性呼吸窘迫综合征(ARDS)大鼠模型肺细胞因子表达的影响,探讨其用于防治ARDS的可能性。方法 腹腔注射内毒素(LPS)1 ml/kg(0.3 ml),16 h后在机械通气下气管内滴注1 mg(0.5 ml)LPS建立大鼠内毒素性ARDS模型。32只大鼠随机分为ARDS常温组(AN组)、ARDS低温组(AH组)、生理盐水常温组(NN组)及生理盐水低温组(NH组),每组8只。建模成功后3 h处死大鼠,用酶联免疫吸附法测定4组动物支气管肺泡灌洗液(BALF)中肿瘤坏死因子(TNF-α)、白细胞介素-6(IL-6)的浓度。结果 气管内滴注LPS后成功建立大鼠内毒素性ARDS模型。AH组BALF中TNF-α、IL-6的浓度显著低于AN组(P<0.01)。NH组与NN组比较,TNF-α、IL-6的含量差异无显著性(P>0.01)。结论 低温有显著抑制内毒素性ARDS大鼠模型肺表达TNF-α、IL-6的作用,提示中度低温可能成为防治ARDS的辅助方法。