American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Oct 1999
Characteristics of polyclonal endemicity of Pseudomonas aeruginosa colonization in intensive care units. Implications for infection control.
We investigated the endemicity of Pseudomonas aeruginosa in intensive care units (ICUs) through analyses of surveillance cultures (from the rectum, stomach, oropharynx, and trachea; n = 1,089), and clinical cultures (n = 2,393) from 297 consecutive patients. Multiple isolates of P. aeruginosa (n = 353) were genotyped. Variables associated with acquisition of respiratory tract colonization (RTC) were tested in a risk factor analysis. ⋯ In eight patients (21%), no route could be demonstrated for colonization. Antibiotics providing P. aeruginosa with a selective growth advantage were associated with acquired RTC. Endemicity of colonization with P. aeruginosa is characterized by polyclonality, and seems to be maintained by continuous admittance of colonized patients and selection pressure from antibiotics rather than by cross-acquisition.
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Am. J. Respir. Crit. Care Med. · Oct 1999
Compartmentalization of the inflammatory response to inhaled grain dust.
Interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor (TNF)-alpha, and the secreted form of the IL-1 receptor antagonist (sIL-1RA) are involved in the inflammatory response to inhaled grain dust. Previously, we found considerable production of these cytokines in the lower respiratory tract of workers exposed by inhalation to aqueous extracts of corn dust extract. Alveolar macrophages (AM) have long been considered the cell type responsible for producing these cytokines, and only recently has it been realized that airway epithelial cells may also be involved in cytokine production. ⋯ Thus, within 6 h after inhalation exposure to corn dust extract, BE appear to contribute to airway inflammation by producing IL-8. AMs are responsible for most of the IL-1beta and IL-6 production in the alveolar region, whereas AMs and PMNs both produce sIL-1RA. Our findings suggest that the inflammatory response to inhaled grain dust is compartmentalized, involving specific mediators of inflammation released by macrophages, neutrophils, and airway epithelial cells.
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Am. J. Respir. Crit. Care Med. · Oct 1999
Plasma leptin is related to proinflammatory status and dietary intake in patients with chronic obstructive pulmonary disease.
Chronic obstructive pulmonary disease (COPD) is a syndrome of chronic wasting, in part associated with a chronic inflammatory response. The aim of this study was to investigate cross-sectionally and prospectively the potential role of leptin in relation to systemic inflammation in the regulation of the energy balance in COPD. Body composition by deuterium dilution, resting energy expenditure (REE) by indirect calorimetry, and plasma concentrations of leptin and soluble tumor necrosis factor (TNF) receptors (sTNF-R) 55 and 75 by ELISA were measured in 27 male patients with emphysema and 15 male patients with chronic bronchitis (disease-subtype defined by high-resolution computed tomography [HRCT]). ⋯ This proposed cytokine-leptin link in pulmonary cachexia may explain the poor response to nutritional support in some of the cachectic patients with COPD and may open a novel approach in combating this significant comorbidity in COPD. Schols AMWJ, Creutzberg EC, Buurman WA, Campfield LA, Saris WHM, Wouters EFM. Plasma leptin is related to proinflammatory status and dietary intake in patients with chronic obstructive pulmonary disease.