Work-related eye symptoms and respiratory symptoms in female cleaners.
(49/1094)
A prospective study was conducted in order to describe the incidence of eye symptoms, nose or throat symptoms, asthma and bronchitis among cleaners compared with former cleaners and according to the 'use of sprayers'. In 1989 and in 1991 questionnaire-based studies were conducted among female cleaners employed at Danish nursing homes, schools and offices. A cohort of 1,011 females was followed over two years. At baseline in 1989, the average age was 45 years and the average of seniority was 10 years. Overall, the cleaners tended to have the same or higher risk of developing respiratory symptoms compared to former cleaners. The 'use of sprayers' during the follow-up period was associated with an increased risk of eye and respiratory symptoms. (+info)
Agarose plug instillation causes goblet cell metaplasia by activating EGF receptors in rat airways.
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We hypothesized that foreign bodies in airways cause inflammation leading to goblet cell metaplasia. Instilled agarose plugs lodged in the bronchi of pathogen-free rats caused a time-dependent increase in Alcian blue-periodic acid-Schiff staining that was detected within 24 h and markedly increased at 72 h. Control bronchi contained no pregoblet or goblet cells, but plugged bronchi contained many pregoblet and goblet cells and a decrease in nongranulated secretory cells. In situ hybridization showed no expression of MUC5AC in control airways, but plugged airways showed a marked expression. Control bronchi showed sparse staining for epidermal growth factor receptor (EGFR) protein, but plugged bronchi showed intense EGFR staining in the epithelium. Pretreatment with an EGFR tyrosine kinase inhibitor (BIBX1522) prevented Alcian blue-periodic acid-Schiff staining and MUC5AC gene expression in plugged bronchi. Pretreatment with tumor necrosis factor-alpha neutralizing antibody or pretreatment with cyclophosphamide abolished plug-induced EGFR protein expression and goblet cell metaplasia. Thus instillation of agarose plugs induces profound goblet cell metaplasia by causing EGFR expression and activation. (+info)
Peripheral airway findings in chronic obstructive pulmonary disease using an ultrathin bronchoscope.
(51/1094)
The authors performed bronchoscopic examination using an ultrathin bronchoscope to determine the characteristics of the peripheral airways in chronic obstructive pulmonary disease (COPD). The study population comprised 13 healthy control subjects, 10 patients with chronic bronchitis without airflow limitation, and 20 patients with COPD. The COPD patients were divided clinically into 10 with chronic bronchitis and 10 with pulmonary emphysema. The peripheral airways were examined using an ultrathin bronchoscope. In chronic bronchitis, peripheral airways of the 11th or 12th generation showed a high frequency of obstruction and mucosal changes such as granulation. In pulmonary emphysema, the peripheral airways frequently showed a net-like appearance of the bronchial epithelium and obstruction at the 11th or 12th generation. Morphological changes of the small airways in chronic obstructive pulmonary disease can be detected by an ultrathin bronchoscope, and this method is likely to be useful for investigating the small airways in vivo. (+info)
International study comparing cefdinir and cefuroxime axetil in the treatment of patients with acute exacerbation of chronic bronchitis.
(52/1094)
OBJECTIVES: To assess the efficacy and tolerability of three antibiotic regimens in patients with acute exacerbation of chronic bronchitis. METHODS: In this double-blind, randomized, multicentered, parallel-group study, patients received once-daily cefdinir 600 mg, twice-daily cefdinir 300 mg, or twice-daily cefuroxime axetil 250 mg for 10 days. Primary efficacy measures were microbiologic eradication rate, by pathogen and by patient, and clinical response rate, by patient. RESULTS: Of 1045 patients, 589 were evaluable for efficacy. At baseline, most patients had moderate or severe cough and sputum production as well as rhonchi, wheezing, and dyspnea. The microbiologic eradication rates by pathogen were 90% with once-daily cefdinir, 85% with twice-daily cefdinir, and 88% with twice-daily cefuroxime. The corresponding values for microbiologic eradication rate by patient were 90% (once-daily cefdinir), 85% (twice-daily cefdinir), and 86% (twice-daily cefuroxime). The respective clinical response rates by patient were 81%, 74%, and 80%. There were no significant differences in the incidence of drug-related adverse events or discontinuations due to adverse events. Diarrhea was the most frequent complaint. CONCLUSIONS: The results indicate that the efficacy and tolerability of cefdinir, once or twice daily, and cefuroxime were comparable with no significant differences between the regimens used. (+info)
Skeletal muscle weakness is associated with wasting of extremity fat-free mass but not with airflow obstruction in patients with chronic obstructive pulmonary disease.
(53/1094)
BACKGROUND: Skeletal muscle weakness is a prominent problem in many patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: The aim of the study was to determine the relation between skeletal muscle function, body composition, and lung function in COPD (emphysema and chronic bronchitis) patients and healthy volunteers. DESIGN: In 50 patients with chronic bronchitis, 49 patients with emphysema, and 28 healthy volunteers, skeletal muscle function was assessed by handgrip and linear isokinetic dynamometry. Whole-body and subregional fat-free mass (FFM) were assessed by dual-energy X-ray absorptiometry. RESULTS: Whole-body and extremity FFM were significantly lower in patients with emphysema (P < 0.001) and chronic bronchitis (P < 0.05) than in healthy volunteers, but trunk FFM was significantly lower only in patients with emphysema (P < 0.001). Extremity FFM was not significantly different between the COPD subtype groups, despite significantly lower values for whole-body and trunk FFM (P < 0.05) in patients with emphysema. Absolute skeletal muscle function (P < 0. 001) and muscle function per kilogram of whole-body FFM were significantly lower in both COPD subtype groups than in healthy volunteers (P < 0.05), but no significant difference was found between patients with chronic bronchitis and those with emphysema. Muscle function per kilogram of extremity FFM was not significantly different between the 3 groups and was not associated with forced expiratory volume in 1 s. CONCLUSION: Skeletal muscle weakness is associated with wasting of extremity FFM in COPD patients, independent of airflow obstruction and COPD subtype. (+info)
Differences in airway responsiveness to acetaldehyde and methacholine in asthma and chronic bronchitis.
(54/1094)
Inhaled acetaldehyde may induce bronchoconstriction in asthmatic subjects and provides a new method to investigate airway responsiveness. The objective of the study was to determine whether acetaldehyde was a more specific stimulus than methacholine in differentiating asthma from chronic bronchitis with or without airflow limitation. Bronchial provocation challenges with methacholine and acetaldehyde were performed in 62 asthmatics and in 59 smokers with chronic bronchitis (32 with chronic bronchitis alone and 27 with chronic bronchitis and coexisting chronic obstructive pulmonary disease (COPD)). The response to both bronchoconstrictor agents was measured by the provocative concentration required to produce a 20% fall in forced expiratory volume in one second (FEV1; PC20). The two types of challenge yielded a similarly high level of sensitivity (100% for methacholine and 92% for acetaldehyde) in revealing airway hyperresponsiveness in asthma. However, bronchoprovocation with acetaldehyde yielded considerably greater specificity (95%) than bronchoprovocation with methacholine (24%) in separating asthma from chronic bronchitis. In subjects with asthma, methacholine and acetaldehyde responsiveness were weakly but significantly correlated (r=0.42, p=0.001) but no correlation was found between airway responsiveness to acetaldehyde and baseline FEV1 (r=0.13, p=0.33). These findings suggest that the demonstration of bronchoconstriction in response to acetaldehyde may be a more specific test than methacholine in the differentiation of asthma from chronic bronchitis. Furthermore, methacholine and acetaldehyde hyperresponsiveness are not reflecting the same pathophysiological process in the airways. (+info)
Bronchial inflammation in acute bacterial exacerbations of chronic bronchitis: the role of leukotriene B4.
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Neutrophils recruited to the airways in chronic obstructive pulmonary disease (COPD) are thought to mediate tissue destruction. Neutrophil recruitment is increased during bacterial exacerbations. The inflammatory process was studied in patients with an acute exacerbation of COPD in order to ascertain the role of leukotriene B4 (LTB4). The sputum of eight subjects with a bacterial exacerbation of COPD was analysed for neutrophil products (myeloperoxidase, elastase) and chemoattractants (interleukin-8 (IL-8) and LTB4). The contribution of LTB4 to the chemotactic activity of the sputum sol phase was determined using the LTB4 receptor antagonist LY293111. The concentrations of the serum acute phase proteins alpha1-proteinase inhibitor, alpha1-antichymotrypsin and C-reactive protein were measured. All patients received appropriate broad-spectrum antibiotic treatment for 7-14 days. Initially, the sputum myeloperoxidase activity was high, indicating neutrophil influx; this was associated with high levels of IL-8 and LTB4. All these concentrations fell with treatment (p<0.01). The chemotactic activity of the sputum was raised on presentation and fell with treatment (p<0.01). LTB4 contributed approximately 30% of the total chemotactic activity on presentation; this diminished with therapy. All acute phase proteins were raised on presentation and fell with therapy (p<0.01). These findings suggest that leukotriene B4 contributes to neutrophil influx into the airway in chronic obstructive pulmonary disease and may influence disease progression. (+info)
Antigen-induced airway inflammation and hyper-responsiveness does not enhance airway responses to a subsequent antigen challenge in rats.
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Brown-Norway (BN) rats develop airway hyper-responsiveness and lung eosinophilia 18-24 h after ovalbumin (OA) challenge. We hypothesized therefore that allergen-induced airway inflammation would further enhance airway responses to a subsequent antigen challenge. Animals were sensitized to both OA and bovine serum albumin (BSA) and, 14 days later, challenged by aerosols with both antigens 24 h apart. Measurements of pulmonary resistance (RL) were made for 8 h after the second antigen challenge and bronchoalveolar lavage (BAL) was performed. Animals were divided into three groups and received two challenges as follows: saline-BSA (n=9), OA-saline (n=8) and OA-BSA (n=10). Sensitization was confirmed by measurements of specific OA-IgE and BSA-IgE. Early responses [determined as the highest value of RL within the first 30 min after the challenge] were absent in all study groups. The late responses [determined from the area under the RL versus time curve from 120 to 480 min after the challenge] were significantly greater in animals challenged with BSA (15.16+/-3.86) compared to saline (3.76+/-4.09; P<0.05). However previous exposure to OA did not further increase the late response in animals subsequently challenged with BSA (20.11+/-3.67) despite enhanced airway responsiveness to LTD4 at this time point. BAL eosinophils and lymphocytes were significantly increased following BSA challenge in previously OA-challenged animals, compared to numbers retrieved from animals previously exposed to saline (P<0.05). These data indicate that previous exposure to OA did not further increase the LR to a second antigen challenge despite substantial increases in airway inflammatory cells and airway hyper-responsiveness to LTD4. (+info)