The current state of workers' pneumoconiosis in relationship to dusty working environments in Okayama Prefecture, Japan.

This study involved the examination of 1,006 chest x-ray films of workers from the industries devoted to shipyard welding, stone grinding, and refractory crushing in southern Okayama prefecture. Of the reviewed films, analysis was focused on subjects with a profusion rate of 0/1 as well as pneumoconiotic subjects (exhibiting profusion rates of 1/0 or greater) in order to discover cases in the beginning stages. One-hundred-and-seventy-four films illustrated a profusion rate of 0/1 or greater, and the proportion of this profusion rate was revealed to be highest in shipyard welders. Even some workers under 40 years of age were found to have already developed pneumoconiosis. Of these 1,006 subjects, 30 volunteers permitted us to measure their personal dust exposure concentrations. The measured concentration of the shipyard welders' dust exposure (respirable dust; 3.3 86.3 mg/m3, total dust; 7.5-117.0 mg/m3) was higher than those of the other 2 industries. Statistical differences among the industries were observed in the respirable dust concentrations. A statistically significant positive correlation was demonstrated between the working duration in dusty environments and the rate of profusion. The present findings suggest the need for taking adequate measures in Okayama in order to prevent workers from developing, or to help retard the progression of, pneumoconiosis.</p

The role of fibronectin in bronchoalveolar lavage fluid of asthmatic patients.

Allergic and chronic inflammation of the airway is regarded as the main pathogenesis of bronchial asthma, in which adhesion of inflammatory cells requires the expression of adhesion molecules. Thus, to clarify the role of fibronectin (FN) in the airway inflammation of bronchial asthma, FN levels in plasma and bronchoalveolar lavage fluid (BALF) from bronchial asthmatics were determined. FN concentrations in plasma and BALF were measured by enzyme-linked immunosorvent assay (ELISA) in 17 asthmatic patients and 10 healthy controls to elucidate the role of FN in allergic inflammation. The mean FN/albumin (Alb) level in the BALF of asthmatic patients was 2.973 micrograms/mg, which was significantly higher than that of healthy controls (0.727 microgram/mg). Non-atopic asthmatics showed a significantly higher level of FN in their BALF in comparison with atopic asthmatics, although the ratio of FN to albumin showed no significant difference. FN levels in BALF correlated significantly with total cell density (r = 0.71, P &#60; 0.05) and alveolar macrophage density (r = 0.64, P &#60; 0.05). FN levels in plasma did not correlate with those in BALF. In conclusion, increased FN in BALF, which was produced locally in the airways of asthmatic patients, is actively involved in the regulation of allergic inflammation.</p

Plasma fibronectin in asthmatic patients and its relation to asthma attack.

This study investigated the relation between asthma attacks and levels of plasma fibronectin (FN) and serum eosinophilic cationic protein (ECP) in patients with bronchial asthma in order to clarify the role of FN in the airway inflammation of bronchial asthma. Plasma levels of FN were significantly higher (P &#60; 0.025) in patients with bronchial asthma than in healthy controls. They were also significantly higher (P &#60; 0.05) in non-atopic asthmatics than in atopic asthmatics. Furthermore, plasma FN was lower during the attack than the non-attack stage (P &#60; 0.025), and a significant increase of plasma FN was noted (P &#60; 0.05) in asthmatics who had more severe and more frequent attacks. Serum levels of ECP were significantly higher during the attack than the non-attack stage (P &#60; 0.005). An increase of plasma FN in the non-attack stage after attacks showed a significant correlation (P &#60; 0.05) with a decrease of serum ECP. These observations clearly indicate that the decrease in plasma FN associated with attacks is closely related to aggravation of airway inflammation, and that the increase in plasma FN in the non-attack stage reflects chronic airway inflammation. These results suggest that the fluctuation in plasma levels of FN may be one of the factors affecting allergic inflammation and attacks in bronchial asthma.</p

Studies on clincopathological changes in interstitial lung diseases. II. Gallium-67 kinetics in the chest and cells obtained by bronchoalveolar lavage.

Gallium-67 citrate ((67)Ga) is known to accumulate in inflammatory areas. Though the exact mechanism of the transportation and localization of (67)Ga citrate in foci of inflammaion is still obscure, (67)Ga scintgraphy has been used clinically to evaluate patients with interstitial pneumonia with regard to disease activity and progression. Quantitative analysis using (67)Ga scintigraphy has been attempted several times, but the results have been inadequate, even with computer analysis. In this study, the combination of (67)Ga scintigraphy and bronchoalveolar lavage (BAL) was applied to patients with various types of interstitial pneumonia to estimate quantatively (67)Ga accumlation in the lungs. The radio activity of BAL fluid and peripheral blood were measured directly, and the ratio of radioactivity of BAL fluid/peripheral blood was calculated for each of the patients. Radioactivity in the peripheral blood was contained mainly in the plasma. On the other hand, most radioactivity in BAL fluid was shown to be located in the cellular component. The cellular component of BAL fluid was separated by culture in plastic culture plates into adherent cells (macrophage-enriched fraction) and non-adherent cells (lymphocyte-enriched fraction). Comparison of radioactivity of each cell fraction proved that alveolar macrophages contained most of the (67)Ga citrate in BAL fluid. Therefore, the high (67)Ga uptake in scintigrams of patients with interstitial pneumonia represents the increased number or activated state of alveolar macrophages in the lungs. The direct measurement of (67)Ga radioactivity in BAL fluid could be a useful method to analyze quantatively (67)Ga scintigrams of interstitial pneumonia patients

Studies on clinicopatholgical changes in interstitial lung diseases. I. Fibronectin in bronchoalveolar lavage fluid.

Fibronectin (FN) is known to promote fibroblast proliferation and attachment of collagen fibers at the site of tissue repair or fibrosis. Although increaed levels of FN were shown in bronchoalveolar lavage (BAL) fluid of patients with interstitial pneumonia, the source of FN and the role of FN in the pathogenesis of interstitial pneumonia are still obscure. BAL fluid of patients with various types of interstitial pneumonia were obtained to measure FN and albumin (Alb) levels and to examine the cellular components. Because of the different recovery rate of BAL fluid, the FN/Alb ratio of the BAL fluid was evaluated as the real FN level in the lungs. A high FN/Alb ratio was shown in patients with idiopathic interstitial pneumonia, interstitial pneumonia with rheumatoid arthritis, hypersensitivity pneumonitis, and sarcoidosis in comparison with normal volunteers. Patients with impaired pulmonary function or acute and progressive interstitial pneumonia were shown to have a higher FN/Alb ratio than patients with normal pulmonary function or inactive interstitial penumonia. The levels of FN in BAL fuid showed a statistically significant correlation with total cell, alveolar macrophage and neutrophil concentrations of BAL fluid, but not with the lymphocyte concentration. Alveolar macrophages, isolated as adhesive cells by a brief incubation in plastic culture plates, were cultured for 48 hours, and the level of FN in the culture medium was measured. FN production by alveolar macrophages was greater in patients with interstitial pneumonia than in norman volunteers. These data suggest that the local increased production of FN might accelerate the fibrotic process in the alveolar wall, following the accumulation of alveolar macrophages and other cellular components