Fractional exhaled NO and serum pneumoproteins after swimming in a chlorinated pool.

Purpose: The purpose of this study was to examine whether a swimming session performed in a pool sanitized with chlorine-based agents induces lung inflammation, modifies lung epithelium permeability, and alters lung function.

Methods: Eleven volunteers performed two standardized swimming sessions: one in a nonchlorinated indoor swimming pool and the other one in a chlorinated indoor pool. Lung inflammation was assessed by fractional exhaled nitric oxide (FE(NO)).

Intracellular storage of surfactant and proinflammatory cytokines in co-cultured alveolar epithelium and macrophages in response to increasing CO2 and cyclic cell stretch.

Cell stretch stimulates both surfactant and cytokine production. The authors proposed that stretch, through these effects, modifies the pathogenesis of lipopolysaccharide-induced acute lung injury (ALI), and that this is CO(2) dependent. Rat alveolar type II cells and macrophages were co-cultured with lipopolysaccharide in 5%, 10%, or 20% CO(2) +/- stretch (30%, 60 cycles/min) for 6 hours.

Hypercapnic acidosis modulates inflammation, lung mechanics, and edema in the isolated perfused lung.

Objective: Low tidal volume (V(T)) ventilation strategies may be associated with permissive hypercapnia, which has been shown by ex vivo and in vivo studies to have protective effects. We hypothesized that hypercapnic acidosis may be synergistic with low V(T) ventilation; therefore, we studied the effects of hypercapnia and V(T) on unstimulated and lipopolysaccharide-stimulated isolated perfused lungs.

Materials And Methods: Isolated perfused rat lungs were ventilated for 2 hours with low (7 mL/kg) or moderately high (20 mL/kg) V(T) and 5% or 20% CO(2), with lipopolysaccharide or saline added to the perfusate.

Stretch and CO2 modulate the inflammatory response of alveolar macrophages through independent changes in metabolic activity.

Ventilatory-induced strain can exacerbate acute lung injury (ALI). Current ventilation strategies favour low tidal volumes and high end-expiratory volumes to 'rest' the lung, but can lead to an increase in CO2. Alveolar macrophages (AM) play a pivotal role in ALI through the release of inflammatory mediators.

Circulating surfactant protein-B levels increase acutely in response to exercise-induced left ventricular dysfunction.

1. As a result of its enormous surface area and necessary thinness for gas exchange, the alveolocapillary barrier is vulnerable to mechanical disruption from raised pulmonary microvascular pressure (Pmv). 2.

Effect of CO2 on LPS-induced cytokine responses in rat alveolar macrophages.

Alveolar macrophages (AM) may be exposed to a range of CO(2) and pH levels depending on their location in the alveoli and the health of the lung. Cytokines produced by AM contribute to inflammation in acute lung injury (ALI). Current ventilatory practices for the management of ALI favor low tidal volumes, which can give rise to increases in CO(2) and changes in pH of the alveolar microenvironment.

Plasma surfactant protein-B: a novel biomarker in chronic heart failure.

Background: In chronic heart failure (CHF), elevated pulmonary microvascular pressure (P(mv)) results in pulmonary edema. Because elevated P(mv) may alter the integrity of the alveolocapillary barrier, allowing leakage of surfactant protein-B (SP-B) from the alveoli into the circulation, we aimed to determine plasma levels of SP-B in CHF and their relation to clinical status.

Methods And Results: Fifty-three outpatients with CHF had plasma SP-B and N-terminal proBNP (NT-proBNP) assayed, in addition to a formalized clinical assessment at each clinic review over a period of 18 months.

Determinants of serum levels of surfactant proteins A and B and Clara cell protein CC16.

Increased leakage of surfactant proteins A and B (SP-A and SP-B) and Clara cell secretory protein (CC16) from the air spaces into the circulation occurs in a range of respiratory conditions. However, circulating levels depend not only on the rate of entry into the circulation, but also on the rate of clearance. In order to clarify the role of the kidney in the clearance of these proteins, serum levels were related to markers of glomerular filtration in 54 non-smoking patients with varying degrees of renal dysfunction, none of whom had respiratory disease or were receiving dialysis at the time of sampling.

Prolonged alveolocapillary barrier damage after acute cardiogenic pulmonary edema.

Objectives: To determine whether acute cardiogenic pulmonary edema is associated with damage to the alveolocapillary barrier, as evidenced by increased leakage of surfactant specific proteins into the circulation, to document the duration of alveolocapillary barrier damage in this setting, and to explore the role of pulmonary parenchymal inflammation by determining if circulating tumor necrosis factor-alpha is increased after acute cardiogenic pulmonary edema.

Design: Prospective, observational study.

Setting: Critical care, cardiac intensive care, and cardiology wards of a tertiary-care university teaching hospital.

Infarct-induced chronic heart failure increases bidirectional protein movement across the alveolocapillary barrier.

Chronic heart failure (CHF) is associated with adaptive structural changes at the alveolocapillary barrier that may be associated with altered protein permeability. Bidirectional protein movement across the barrier was studied in anesthetized rats with infarct-induced CHF by following (125)I-labeled albumin ((125)I-albumin) flux into the alveoli and the leakage of surfactant protein (SP)-B from the alveoli into the circulation. Three groups were studied: controls [0% left ventricular (LV) infarction], moderate infarct (25-45% LV infarction), and large infarct (>46% LV infarction).

Endotoxin induces respiratory failure and increases surfactant turnover and respiration independent of alveolocapillary injury in rats.

Although endotoxin-induced acute lung injury is associated with inflammation, alveolocapillary injury, surfactant dysfunction, and altered lung mechanics, the precise sequence of these changes is polemic. We have studied the early pathogenesis of acute lung injury in spontaneously breathing anesthetized rats after intravenous infusion of Salmonella abortus equi endotoxin. The animals became hypoxic, and airway resistance, tissue resistance, lung elastance, and static compliance all deteriorated well before any change in alveolar neutrophils, macrophages, lung fluid (99mTc-labeled diethylenetriamine pentaacetic acid), or 125I-albumin flux, which were only appreciably increased at 8.