Staphylococcus aureus Alpha-Toxin in Deep Tracheal Aspirates-Preliminary Evidence for Its Presence in the Lungs of Sepsis Patients.

The pore forming alpha-toxin (hemolysin A, Hla) of Staphylococcus aureus (S. aureus) is a major virulence factor with relevance for the pathogenicity of this bacterium, which is involved in many cases of pneumonia and sepsis in humans. Until now, the presence of Hla in the body fluids of potentially infected humans could only be shown indirectly, e.g., by the presence of antibodies against Hla in serum samples or by hemolysis testing on blood agar plates of bacterial culture supernatants of the clinical isolates. In addition, nothing was known about the concentrations of Hla actually reached in the body fluids of the infected hosts. Western blot analyses on 36 samples of deep tracheal aspirates (DTA) isolated from 22 hospitalized sepsis patients using primary antibodies against different epitopes of the Hla molecule resulted in the identification of six samples from five patients containing monomeric Hla (approx. 33 kDa). Two of these samples showed also signals at the molecular mass of heptameric Hla (232 kDa). Semiquantitative analyses of the samples revealed that the concentrations of monomeric Hla ranged from 16 to 3200 ng/mL. This is, to our knowledge, the first study directly showing the presence of S. aureus Hla in samples of airway surface liquid in human patients.

Intensive insulin therapy and pentastarch resuscitation in severe sepsis.

BACKGROUND: The role of intensive insulin therapy in patients with severe sepsis is uncertain. Fluid resuscitation improves survival among patients with septic shock, but evidence is lacking to support the choice of either crystalloids or colloids. METHODS: In a multicenter, two-by-two factorial trial, we randomly assigned patients with severe sepsis to receive either intensive insulin therapy to maintain euglycemia or conventional insulin therapy and either 10% pentastarch, a low-molecular-weight hydroxyethyl starch (HES 200/0.5), or modified Ringer's lactate for fluid resuscitation. The rate of death at 28 days and the mean score for organ failure were coprimary end points. RESULTS: The trial was stopped early for safety reasons. Among 537 patients who could be evaluated, the mean morning blood glucose level was lower in the intensive-therapy group (112 mg per deciliter [6.2 mmol per liter]) than in the conventional-therapy group (151 mg per deciliter [8.4 mmol per liter], P<0.001). However, at 28 days, there was no significant difference between the two groups in the rate of death or the mean score for organ failure. The rate of severe hypoglycemia (glucose level, < or = 40 mg per deciliter [2.2 mmol per liter]) was higher in the intensive-therapy group than in the conventional-therapy group (17.0% vs. 4.1%, P<0.001), as was the rate of serious adverse events (10.9% vs. 5.2%, P=0.01). HES therapy was associated with higher rates of acute renal failure and renal-replacement therapy than was Ringer's lactate. CONCLUSIONS: The use of intensive insulin therapy placed critically ill patients with sepsis at increased risk for serious adverse events related to hypoglycemia. As used in this study, HES was harmful, and its toxicity increased with accumulating doses. (ClinicalTrials.gov number, NCT00135473.)

Epidemiology of sepsis in Germany: results from a national prospective multicenter study.

OBJECTIVE: To determine the prevalence and mortality of ICU patients with severe sepsis in Germany, with consideration of hospital size. DESIGN: Prospective, observational, cross-sectional 1-day point-prevalence study. SETTING: 454 ICUs from a representative nationwide sample of 310 hospitals stratified by size. Data were collected via 1-day on-site audits by trained external study physicians. Visits were randomly distributed over 1 year (2003). PATIENTS: Inflammatory response of all ICU patients was assessed using the ACCP/SCCM consensus conference criteria. Patients with severe sepsis were followed up after 3 months for hospital mortality and length of ICU stay. MEASUREMENTS AND RESULTS: Main outcome measures were prevalence and mortality. A total of 3,877 patients were screened. Prevalence was 12.4% (95% CI, 10.9-13.8%) for sepsis and 11.0% (95% CI, 9.7-12.2%) for severe sepsis including septic shock. The ICU and hospital mortality of patients with severe sepsis was 48.4 and 55.2%, respectively, without significant differences between hospital size. Prevalence and mean length of ICU stay of patients with severe sepsis were significantly higher in larger hospitals and universities (

Akrinor-induced relaxation of pig coronary artery in vitro is transformed into alpha1-adrenoreceptor-mediated contraction by pretreatment with propranolol.

Akrinor (AKR), a mixture of theodrenaline (TDR) and cafedrine (CDR), is a sympathomimetic agent used to counter transitory hypotension. Although some cases of vascular complications associated with AKR have been reported there are no experimental data about its direct effects on coronary arteries. The effects of AKR, TDR, CDR, and ephedrine (EDR) were studied on the isometric contraction of the ring preparations of pig coronary arteries precontracted with KCl. The influence of endothelium removal and preincubation with nonselective beta-adrenoreceptor antagonist propranolol (PROP), alpha(1)-adrenoreceptor antagonist prazosin, dopamine receptor antagonist SCH 23390, and adenosine receptor antagonist CGS 15943 were also tested. AKR, TDR, and CDR produced relaxation of the preparations. Preparations without endothelium were more sensitive to AKR relaxing effects. EDR produced an increase of vascular ring tonus. AKR, TDR, and EDR produced contraction in preparations pretreated with PROP. Higher concentrations of AKR relaxed PROP-pretreated preparations. AKR-induced contraction could be prevented by pretreatment with prazosin. Dopamine and adenosine receptor antagonists did not influence relaxing effects of AKR. In conclusion, AKR and its constituents induce the relaxation of pig coronary artery preparations precontracted with KCl. The observed contraction in the preparations pretreated with PROP was probably due to stimulation of unmasked alpha(1)-adrenoreceptors.

Thermostatic tissue platform for intravital microscopy: 'the hanging drop' model.

Intravital microscopy imposes the particular problem of the combined control of the body temperature of the animal and the local temperature of the observed organ or tissues. We constructed and tested, in the rat ileum microcirculation preparation, a new organ-support platform. The platform consisted of an organ bath filled with physiological solution, and contained a suction tube, a superfusion tube, an intestine-support hand that was attached to a micromanipulator and a thermometer probe. To cover the intestine we used a cover glass plate with a plastic ring glued on its upper surface. After a routine procedure (anaesthesia, monitoring and surgery), the intestine segment (2-3 cm long) was gently exteriorized and placed on the 'hand' of the organ support. A small part of the intestine formed a small 'island' in the bath that was filled with physiological salt solution. The cover glass was secured in place. The physiological salt solution from the superfusion tube, which was pointed to the lower surface of the cover glass, formed a 'hanging drop'. The objective of the microscope was then immersed into distilled water that was formed by the cover glass plastic ring. The 'hanging drop' technique prevented any tissue quenching, ensured undisturbed microcirculation, provided for stable temperature and humidity, and permitted a clear visual field.