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D Lamb

Publications and source records attributed to D Lamb.

150 records · Page 9Linked to original sources
PubMedDate not supplied

Intratracheal injection of crocidolite asbestos depresses the secretion of tumor necrosis factor by pleural leukocytes in vitro.

Tumor necrosis factor (TNF) is a cytokine released predominantly by monocytes/macrophages that has been shown to modulate a variety of different immune and metabolic functions. To understand the regulatory mechanisms of TNF in governing responses in the pleural cavity following deposition of fibrous dust in the airspace of the lung, we studied the capability of leukocytes, lavaged from the pleural cavity, to release TNF in culture. TNF production by lavaged pleural leukocytes was measured using the L-929 TNF-sensitive cell line, after intratracheal instillation of crocidolite asbestos. A high level of TNF activity was found in the supernatants of normal, unstimulated pleural leukocytes; the addition of 100 ng/ml lipopolysaccharide to the culture increased the activity up to threefold. Following intratracheal instillation of 5 mg crocidolite asbestos, the pleural leukocytes secreted less TNF than the control. With increasing mass of intratracheally instilled asbestos, there was a dose-dependent reduction in TNF release. Changes in the population of the pleural leukocytes or their number could not be related to variation in TNF activity. These results suggest that exposure of rat lungs to crocidolite asbestos by intratracheal instillation affects the response of pleural leukocytes without causing changes in the population. Such changes in the bronchoalveolar space may be related to the pleural pathology found in asbestos-exposed individuals.

Animals↗
PubMedDate not supplied

Physiological/pathological correlations in coal workers' pneumoconiosis.

There is remarkably little information about the direct relationship of physiological abnormality in coal workers' pneumoconiosis with structural changes in the lung and there are major difficulties in attempting such a correlation. The general population, including coal workers, has a regrettably high prevalence of pulmonary functional abnormalities attributable to chronic bronchitis or to emphysema occurring either separately or together. The pathological basis for the functional impairment in chronic bronchitis and possible functional sequelae to the anatomical changes of emphysema are not clearly understood, making it extremely difficult to identify separately the functional effects associated with coal workers' pneumoconiosis. Any study of coal workers' pneumoconiosis must take into account the background population. The published investigations relating the functional abnormalities and pathological changes in the lung in coal workers' pneumoconiosis are reviewed. The relationship of functional change to emphysema, chronic bronchitis, cor pulmonale and the specific lesions of coal workers' pneumoconiosis are dealt with. There is great need for further work in this field, both in the form of simple studies of pathological changes in miners' lungs as well as more complex attempts to correlate such pathological surveys with physiological abnormalities in life.

Bronchitis↗