新型显色基质法鲎试验对肺部革兰氏阴性菌感染患者的诊断意义

应用新型显色基质法鲎试验（ＮＣＬＡ）测定４１例肺部革兰阴性（Ｇ＾－）细菌感染患者）Ｇ组）；３２例肺部非革兰氏阴性细菌感染患者（非Ｇ组）；４２例无细菌感染的肺病患者（无感染组）的血浆内毒素浓度、并与１００例健康者（对照）比较，Ｇ组血浆内毒素水平明显高于对照组，非Ｇ组及无感染组（Ｐ均〈０．０１）。提示新型显色基质法鲎试验有助于肺部Ｇ细菌感染作出快速，灵敏的诊断。     

Hypersensitivity to endotoxin hepatotoxicity in rats with inflammatory lesions

Summary The ratio of sinusoidal nonparenchymal cells to hepatocytes in rat liver was significantly increased following induction of inflammation, and decreased after subsequent exposure to endotoxin, particularly in the region around the terminal portal venules. Rats with inflammatory lesions were more sensitive to endotoxin hepatocytotoxicity than normal controls, as judged from the dose-dependent increase in activity of serum transaminases and from the extent of liver tissue injury. In addition, these animals, which were already in a state of depletion of hepatic glycogen, demonstrated marked hyperglycemia 24 h after endotoxin administration in small doses of less than 2 mg/kg.     

Parenteral soya bean fat emulsions potentiate the hepatotoxicity ofE. coli endotoxin in suckling rats

Summary A dose of soy bean fat emulsion which was injected i.v. in suckling rats accumulated in the cells of liver parenchyma, both in hepatocytes and in reticuloendothelial cells. Subsequent i.p. injection ofE. coli endotoxin was followed by extensive liver tissue necrosis and increased activities of serum aspartic and alanine aminotransferase. These signs of liver damage were markedly more pronounced than those observed after the administration ofE. coli endotoxin only.     

细菌内毒素对血液流变学特性影响的研究进展

通过分析血液流变特性对病理生理变化的影响,内毒素在导致内毒素血症和多器官功能衰竭中扮演的角色,以及内毒素血症中血液流变特性的变化,由此提示革兰氏阴性菌产生的内毒素与血液流变学特性变化之间关系密切,因此及时降低血液中内毒素的水平对于有效治疗内毒素血症及相关病症具有重大意义.临床上对于内毒素血症的治疗缺乏有效药物,利用固定化多粘菌素B聚苯乙烯微球进行血液灌流可特异地吸附血液中内毒素,降低血液中内毒素的水平,改善血液流变学特性,在急救医学治疗中具有广阔前景.     

感染根管治疗过程中内毒素含量的变化

目的：为了评价根管治疗在清除内毒素方面的作用。方法：采用产色基质法鲎试验对３３例根尖周炎治疗前后根管内的内毒素含量变化进行了检测。结果：有症状的牙和无症状的牙根管内毒素含量有显著差异;治疗前后相比较内毒素含量明显减低;有渗出液的根管经治疗后仍能 检测出少量内毒素存在。结论：根管治疗是消除感染根管内毒素一种有效方法;内毒素与根管渗出液产生有关。     

细菌内毒素对基因免疫小鼠存活率和产仔率的影响

作为第三代疫苗,核酸疫苗具有易操作、低成本等优点,但是其内在危险性还有待进一步研究和排除,在其制备过程中可能掺入的细菌内毒素就是影响因素之一.细菌内毒素是革兰氏阴性菌细胞壁外膜结构中的脂多糖,体内释放后会引起发热、休克等多种病理变化.国外已有体外实验证明内毒素会对小鼠的生殖系统产生影响,本研究旨在通过在体实验探讨内毒素对免疫小鼠的存活率和产仔率的影响.采用常规方法(碱裂解法)、试剂盒2种方法,提取2种pCR3.1-Sry质粒(2种质粒的区别在于是否去除内毒素,其浓度和纯度均经过琼脂糖凝胶电泳和紫外分光光度法分析和控制).作为核酸疫苗对小鼠进行免疫:全程统计免疫小鼠的存活率和产仔率,同时注射灭菌ddH2O作为对照.分子生物学实验结果显示,所制备疫苗具有适宜的浓度和较高的纯度;免疫实验和数字统计结果显示,未去除内毒素实验组小鼠较去除内毒素组的存活率由93%下降到84%、产仔率由87.5%下降到35.7%,而去除内毒素组却与对照组没有明显差异.总之,核酸疫苗制备过程中掺入的细菌内毒素会对免疫小鼠造成较大不良影响,特别是生殖系统,体现在产仔率大幅降低.     

甘氨酸和多粘菌素B合用在体内对内毒素致热性的拮抗作用

目的 :探讨甘氨酸和多粘菌素B在体内对内毒素致热性的拮抗作用。方法 :以内毒素诱导家兔发热 ,实验组预先单独或联合给予相应剂量的甘氨酸和多粘菌素B ,测量各组家兔的直肠体温。结果 :用半剂量的甘氨酸 /多粘菌素B预处理对内毒素致热性有明显的拮抗作用 (P <0 0 5 ) ,并且其效果与预先给予全剂量多粘菌素B者无显著性差异 (P >0 0 5 )。结论 :在家兔体内合用甘氨酸和多粘菌素B预处理可以有效地拮抗内毒素引起的发热 ,并且可以降低单一药物的使用剂量。     

生物医学工程在脓毒症治疗中的应用

探讨生物医学工程技术在治疗革兰氏阴性菌所致脓毒症中的作用。通过分析内毒素的化学结构和内毒素在导致脓毒性休克和多器官功能衰竭（MODS）中扮演的角色，并比较不同生物技术在治疗脓毒症中的效果。显示脓毒症与革兰氏阴性菌产生的内毒素有关，脓毒症的治疗缺乏有效药物。固定化多粘菌素B（PMX－B）血液灌流可特异地吸附血液中内毒素，能有效地降低血液中内毒素和细胞因子浓度，改善血液流变学。利用固定化亲和吸附剂去除血液中内毒素对治疗脓毒症有重要价值。     

Tumor necrosis factor as an antineoplastic agent: pitfalls and promises

The discovery and cloning of the cytokine tumor necrosis factor α (TNF) gave rise to new hopes for a significant victory in the war against cancer. Preclinical in vitro studies in cell cultures and in vivo studies in animal models demonstrated the antitumor capacities of TNF. Although clinical studies were largely made possible by the availability of recombinant TNF, phase I and II clinical trials showed very quickly that the systemic administration of TNF induced severe side effects mainly due to its pleiotropic action on immunocompetent cells. The clinical manifestations of the side effects were similar to those observed during a severe infection and inflammation. Very recently, lessons from these clinical studies yielded refined approaches whereby the toxicity of TNF is limited through local administration, a combination with other therapeutic regimens and targeted gene therapy. These new approaches are slated for larger clinical trials and in the near future might demonstrate the limited but powerful usefulness of TNF as an antineoplastic agent for different types of cancer. Received 7 September 1998; received after revision 15 October 1998; accepted 15 October 1998     

大肠杆菌内毒素对Vero细胞培养的作用研究

将精制大肠杆菌内毒素(E.COliEndotoxin)加入含血清细胞培养液(MEM)中,配制成浓度分别为50、100、200、500EU/mL的细胞培养液 用此培养液对Vero细胞进行培养,测定细胞生长曲线、细胞平均倍增时间、最大增殖浓度及台盼蓝拒染率等指标,研究大肠杆菌内毒素对非洲绿猴肾细胞(Vero)培养的影响 结果显示,内毒素含量为50EU/mL时,Vero细胞仍能正常生长 当内毒素含量逐渐升高,培养时间逐渐延长时,细胞的增殖速度及活率明显下降 这表明,内毒素对Vero细胞的生长及活性具有明显的抑制作用,且该作用具有一定的时间、剂量依赖性