American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Feb 1996
Comparative StudyDifferences in interleukin-8 and tumor necrosis factor-alpha in induced sputum from patients with chronic obstructive pulmonary disease or asthma.
Asthma and chronic obstructive pulmonary disease are characterized by chronic airway inflammation. Studies using bronchoalveolar lavage (BAL) have shown an increased proportion of eosinophils in the BAL fluid from asthmatics compared with that from normal subjects, whereas studies of chronic obstructive pulmonary disease (COPD) have shown increased numbers of neutrophils. Induced sputum allows sampling of respiratory tract secretions from patients and control subjects, providing a noninvasive method of studying airway secretions and allowing characterization of cells and measurement of soluble markers. ⋯ We found a significant increase in neutrophils and increased concentrations of tumor necrosis factor-alpha (TNF alpha) and interleukin-8 (IL-8) in the patients with COPD compared with the smoking and nonsmoking control subjects. Interleukin-8, but not TNF alpha, was significantly higher in the COPD group than in the asthmatic group. We conclude that the cytokines TNF alpha and IL-8 may be involved in the inflammation in COPD.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Occupational disease trends in black South African gold miners. An autopsy-based study.
The change in prevalence in silicosis and pulmonary tuberculosis in black South African gold miners dying from unnatural causes from 1975 to 1991 was studied. Data were analyzed for 16,454 black gold miners. Information on age at death, duration of service, year of autopsy examination, and the prevalence of silicosis and tuberculosis was collected. ⋯ A significant trend for tuberculosis, for year of autopsy, remained after adjustment for the other variables in the model, such as age and duration of service (p = 0.0046). In view of current labor stabilization in the South African mines, one can expect further increases in the prevalence of tuberculosis and silicosis. Lowering of dust levels in the mines is urgently required to prevent the increase of disease burden.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Comparative StudyExogenous surfactants in a piglet model of acute respiratory distress syndrome.
Evidence for surfactant dysfunction in acute respiratory distress syndrome (ARDS) suggests a role for exogenous surfactant which contains apoprotein for resistance to protein inhibition. We compared the effects of KL-4-Surfactant, an artificial preparation containing a synthetic 21 amino acid peptide with SP-B-like activity, with Exosurf, an artificial protein-free surfactant, and Survanta, a bovine protein-containing surfactant, in a saline lung lavage model of ARDS in neonatal piglets. Two sequential series of lung lavages were performed to lower PaO2 < 100 mm Hg, each followed by administration of surfactant or air and a 90-min observation period. ⋯ Only KL-4-Surfactant demonstrated greater pressure-volume characteristics and lower bronchoalveolar protein than those of Controls. We conclude that the physiologic effects of KL-4-Surfactant are more like Survanta in this model. We speculate that KL-4-Surfactant may improve pulmonary function, reduce alveolar protein leak, and thus be efficacious in the treatment of ARDS.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Hypothalamic-pituitary-adrenal axis in corticosteroid-resistant bronchial asthma.
We have examined whether the lack of clinical response to corticosteroids seen in corticosteroid resistant (CR) bronchial asthma is reflected in abnormalities of endogenous cortisol secretion and in the sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis in CR subjects by using a modification of the standard dexamethasone suppression test (DST) in response to 0.25 and 1 mg oral dexamethasone. Five corticosteroid-sensitive (CS) and five CR asthmatic subjects were studied on two occasions 1 mo apart. In the first limb of the study subjects received 0.25 mg of oral dexamethasone, and in the second limb they received 1 mg. ⋯ The levels of urinary free cortisol (nmol/24 h) and predose plasma ACTH (ng/L) and cortisol (nmol/L) were 199 +/- 42, 27.4 +/- 5.7, and 300 +/- 48 (mean +/- SEM), respectively, in the CS group, and 210 +/- 74, 23.4 +/- 6.7, and 263 +/- 32 (mean +/- SEM), respectively, in the CR group (p > 0.05 for all comparisons). Plasma ACTH and cortisol concentrations were not significantly suppressed in either group after 0.25 mg dexamethasone, but were equally suppressed in both groups to undetectable levels by 1 mg dexamethasone. We conclude that CR asthma is not reflected in an altered secretory rate of endogenous cortisol or in an altered sensitivity of the HPA axis to dexamethasone suppression.
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Am. J. Respir. Crit. Care Med. · Feb 1996
Bedside prediction of mortality from bacteremic sepsis. A dynamic analysis of ICU patients.
The prognosis in patients with sepsis depends on severity of acute illness, underlying chronic diseases, and complications associated with infection. Adjusting for these factors is essential for evaluation of new therapies. The purpose of the present study was to determine variables readily identifiable at the bedside that predict mortality in intensive care unit (ICU) patients with sepsis and positive blood cultures. ⋯ The best two independent prognostic factors were the APACHE II score at the onset of sepsis (OR, 1.13 per unit; CI95, 1.08 to 1.17; p = 0.0016) and the number of organ dysfunctions developing thereafter (OR, 2.39; CI95, 2.02 to 2.82; p < 0.001). In ICU patients with sepsis and positive blood cultures, outcome can be predicted by the severity of illness at onset of sepsis and the number of vital organ dysfunctions developing subsequently. These variables are easily assessed at the bedside and should be included in the evaluation of new therapeutic strategies.