Effects of endotoxin on intestinal hemodynamics, glutamine metabolism, and function

The purpose of this study was to investigate the intestinal hemodynamics and gut glutamine metabolism during endotoxemia, and their correlation with altered intestinal absorptive capacity and permeability. Seventeen Sprague-Dawley rats were used in the study. The endotoxin group (ENDO) recieved endotoxin (10 mg/kg intraperitoneally,n=9), while the control group (CONT,n=8) received saline injection. Twelve hours later, D-xylose (0.5 g/kg) and fluorescein isothiocyanate-dextran (FITC-dextran, 750 mg/kg) were given by oral gavage. One hour later abdominal aortic (AA) blood flow, superior mesenteric venous (SMV) flow, mean arterial pressure (MAP), central venous pressure (CVP), and SMV pressure (SMVP) were also measured. The MAP, AA, and SMV blood flow decreased (P<0.05), while the CVP and SMVP increased (P<0.05) in the ENDO group as compared with the CONT group. The ENDO group showed significant decreases for both intestinal glutaminase activity and net intestinal glutamine uptake (P<0.05). The D-xylose concentration in SMV decreased significantly (P<0.05) in the ENDO group as compared with the CONT group. However, the plasma FITC-dextran concentration showed no significant difference between the groups. Endotoxin produced a hypodynamic effect in rats 12h after intraperitoneal administration in association with both a decreased intestinal glutamine metabolism and an absorptive capacity.     

Bacterial colonization and infection in an intensive care unit

One hundred and one patients, nursed in an intensive care unit for at least 24h, were monitored for bacterial colonization and infection. The infection rates were similar to those in other reports. Patients were not generally colonized with common environmental strains in the unit. Bacterial dissemination between patients was uncommon. No gentamicin resistant gram negative or Staphylococcus aureus strains were observed, nor methicillin resistant Staphylococcus aureus strains. the hypothesis that these favourable conditions are partly related to the excellent isolation and barrier nursing facilities in the unit cannot be fully substantiated.     

Endotoxin-induced uveitis (EIU) in the rat: A study of inflammatory and immunological mechanisms

Endotoxin-induced uveitis (EIU) can be produced by systemic injection of endotoxin (ET). It is not clear yet why exclusive ocular involvement occurs in this model. To clarify this question and to establish the sequence of inflammatory events, EIU was induced in Lewis rats by footpad injection of Salmonella ET. Ocular inflammatory response (anterior chamber cells and proteins), aqueous inflammation mediators (thromboxane B₂, prostaglandin E₂, leukotriene B₄ and substance P) and MHC class 2 (Ia) antigen expression in the ciliary body were monitored for 72 hours. Thromboxane B₂ was detected early in the aqueous humor, peaking already 1 hour after ET injection. Prostaglandin E₂ & leukotriene B₄ peaks and a second peak of thromboxane B₂ were recorded 18 hours after ET-injection, at the time of maximal ocular inflammation. MHC-class 2 expression was first detected in the ciliary body stroma at the vascular level 6 hours after ET injection and was massively expressed in the ciliary body epithelium at 18 and 72 hours. It is hypothetized that ciliary body endothelium is particularly sensitive to the effect of ET and is the site of thrombocyte adherence. Vascular damage leads in succession to cellular infiltration, release of inflammation mediators and disruption of blood-ocular barrier. MHC-class 2 expression is a secondary phenomenon and is probably at the origin of additional tissue damage from immune effector mechanisms.     

Is it possible to prevent bacterial adhesion onto ureteric stents?

The aim of this study was to determine whether the use of bactericidal coatings or immersion in antibiotic solution reduces or prevents bacterial adhesion onto ureteric stents. Precut segments of full silicone, silver-coated and hydrogel-coated ureteric stents were incubated with two uropathogenic bacterial strains with and without previous immersion in antibiotic solution. Tobramycin, ceftriaxone and ciprofloxacin solutions were used, as these antibiotics are commonly administered for the prophylaxis and treatment of urinary tract infection (UTI). Microbiological analysis showed that immersion of ureteric stents in ceftriaxone and ciprofloxacin yielded a significant reduction of bacterial adhesion, whereas immersion in tobramycin did not. The surface material of the stents had no direct influence on bacterial adhesion. In this experimental study, neither the silver nor the hydrogel coat reduced bacterial adhesion onto ureteric stents whereas immersion in a suitable antibiotic solution significantly reduced and even prevented this phenomenon, probably due to the adhesion of the antibiotic onto the stent surface. Prevention of bacterial adhesion onto ureteric stents is essential to reduce the risk of UTI in connection with these devices.     

肾移植后细菌败血症治疗过程中内毒素血症和菌血症的动态变化

为研究败血症时细菌溶解的程度对内毒素血症的影响,本文对肾移植术后怀疑为革兰氏阴性杆菌败血症患者的血中内毒素和细菌进行了定量检查。13名患者中有4人血中细菌定量>50cfu/ml,其血中内毒素水平由开始检查到最高峰时相差2～35倍,有一名患者在使用抗生素治疗过程中突然发生休克,最后由于呼吸、循环衰竭而死亡,其血中内毒素明显升高。本文结果表明:对于感染发病率很高的肾移植患者,如何控制和处理抗生素治疗后的高内毒素血症是一个值得研究的问题。血中内毒素和细菌的定量检查可以为及时采取针对性措施,防治内毒素血症提供依据。     

Clinical evaluation of technetium-99m infecton for the localisation of bacterial infection

The aim of the study was to distinguish infection from inflammation in patients with suspected infection using technetium-99m Infecton. Ninety-nine patients (102 studies) referred for infection evaluation underwent imaging with 400 MBq^99mTc-Infecton at 1 and 4 h. Most patients had appropriate microbiological tests and about half (56) had radiolabelled white cell scans as well. No adverse effects were noted in any patient. The clinical efficacy of^99mTc-Infecton depended in part on whether imaging was undertaken during intibiotic therapy for infection or not. In consultation with the microbiologist, 5–14 days of appropriate and successful antibiotic therapy was considered adequate to classify some results as true-negatives. The figures for sensitivity and specificity of^99mTc-Infecton for active or unsuccessfully treated infection were 83% and 91% respectively. It is concluded that^99mTc-Infecton imaging contributed to the differential diagnosis of inflammation. It is being used as the first imaging modality when bacterial infection is suspected.     

亚胺培南/西司他丁与头孢他啶治疗中、重度细菌感染疗效费用分析比较研究

对我院４５例确诊为中、重度细菌感染住院患者进行了亚胺培南／西司他丁与头孢他啶疗效费用分析比较研究。结果表明：２组病例有效率、死亡率无显著性差异；头孢他啶组较亚胺培南／西司他丁组疗程明显延长。亚胺培南／西司他丁每日所需费用明显高于头孢他啶；治疗结束时，前者全部费用并未超过后者；全部住院费用无明显差异。作者认为：决定２种药物全部费用的因素，除与药物单价和每日费用有关，还与药物疗程密切相关。选用药物抗菌作用越强，用药时间即相应缩短，住院时间必然缩短；最终患者住院费用降低     

舒胆合剂防治阻塞性黄疸肾功能障碍的作用机制

目的 探讨在阻塞性黄疸(OJ)时舒胆合剂的抗内毒素及对肾功能的保护作用。方法 SD大鼠胆总管结扎后分3组，每组10只，分别用2mL舒胆合剂、乳果糖液(每100mL含乳果糖67g)、生理盐水灌胃，连用9d。假手术组10只，用2mL生理盐水灌胃。观察内毒素、血和肾组织中内皮素(ET)、一氧化氮(NO)的含量、一氧化氮合酶(NOS)活性及肾功能的变化。结果 舒胆合剂组与乳果糖组血内毒素、血和肾组织ET水平较生理盐水组明显降低，血和肾组织N0、NOS活性、内生肌酐清除率、肾皮质血流量较生理盐水组明显升高。结论 在OJ时，中药舒胆合剂有抗内毒素作用，并通过减少体内内毒素水平来降低体内ET水平，升高N0水平起到保护肾功能的作用。     

纳洛酮与山莨菪碱、躯体刺激对内毒素休克狗血流动力学影响的比较

静脉给予纳洛酮2mg/kg期间可使内毒素休克狗的平均动脉压(MAP)、左心室收缩压(LVSP)及其一阶导数(±dp/dt max)和心力环面积(CFU)增加,但对肾血流量(RBF)、尿量及20h的存活率无明显影响。将本实验结果与山莨菪碱、躯体刺激效应进行比较,表明三者中山莨菪碱对休克动物的循环改善作用最明显。     

Gram-negative bacterial pneumonia with secondary aspergillosis in an AIDS patient

Summary A 40-year-old, HIV-infected female patient received antibiotic treatment for a urinary tract infection. After the initial success of therapy and a symptom-free period, she developed pneumonia with septic shock and adult respiratory distress syndrome (ARDS). In spite of intensive care and respirator therapy with positive end-expiratory pressure (PEEP), she died of infectious toxic shock. Autopsy findings showed relapsing, gramnegative, bacterial pneumonia (morphologically compatible with Klebsiella pneumonia) and secondary, invasive aspergillosis. The pathogenesis and epidemiology of these unusual complications of AIDS are discussed.Abbreviations AIDS acquired immunodeficiency syndrome - ARDS adult respiratory distress syndrome - CDC Centers for Disease Control - HIV human immunodeficiency virus - PEEP positive end-expiratory pressure