Asbestos Burden In Plaques Compared To Content In Lungs

Asbestos Fibers can be deadly when they broken into tiny pieces and inhaled or swallowed. We must all do our part when it comes to raising public awareness about the terrible diseases associated with asbestos exposure. One interesting study is called, “A comparison of asbestos burden in lung parenchyma, lymph nodes, and plaques” by Dodson, RF, Williams, MG Jr., Corn, CJ, Brollo, A, and Blanch, C - Annals of the New York Academy of Sciences. Vol. 643, pp. 53-58. 1991. Here is an excerpt: “The lack of quantitative studies concerning the asbestos burden in plaques has resulted in the statement that the "asbestos fiber content of plaques and pleura appears to be quite different from that of the lung, and these sites are not useful for mineral analysis." The present study was designed to test this concept. The tissue from occupationally exposed individuals was assessed by light and transmission electron microscopy and the fiber burden, types, and dimensions were recorded. Quantitation of the asbestos burden (ferruginous bodies and uncoated fibers) found in the original site of deposition (lung) was compared with that burden found in relocation sites (lymph nodes and pleura).”

A second study is called, “Cell signaling pathways elicited by asbestos” by B.T. Mossman, S Faux, Y Janssen, L A Jimenez, C Timblin, C Zanella, J Goldberg, E Walsh, A Barchowsky, and K Driscoll - Department of Pathology, University of Vermont College of Medicine, Burlington 05405, USA. - Environ Health Perspect. 1997 September; 105(Suppl 5): 1121–1125. Here is an excerpt: “Abstract - In recent years, it has become apparent that minerals can trigger alterations in gene expression by initiating signaling events upstream of gene transactivation. These cascades may be initiated at the cell surface after interaction of minerals with the plasma membrane either through receptorlike mechanisms or integrins. Alternatively, signaling pathways may be stimulated by active oxygen species generated both during phagocytosis of minerals and by redox reactions on the mineral surface. At least two signaling cascades linked to activation of transcription factors, i.e., DNA-binding proteins involved in modulating gene expression and DNA replication, are stimulated after exposure of lung cells to asbestos fibers in vitro. These include nuclear factor kappa B (NF kappa B) and the mitogen-activated protein kinase (MAPK) cascade important in regulation of the transcription factor, activator protein-1 (AP-1). Both NF kappa B and AP-1 bind to specific DNA sequences within the regulatory or promoter regions of genes that are critical to cell proliferation and inflammation. Unraveling the cell signaling cascades initiated by mineral dusts and pharmacologic inhibition of these events may be important for the control and treatment of mineral-associated occupational diseases.”

A third study is called, “Ventilatory failure due to asbestos pleurisy” by Albert Miller, M.D., Alvin S. Teirstein, M.D., Irving J. Selikoff, M.D.b - Volume 75, Issue 6, Pages 911-919 (December 1983). Here is an excerpt: “Abstract - Seven patients are described who had a distinctive syndrome of chest wall restriction caused by asbestos-induced pleural fibrosis. All had severe dyspnea and predominant pleural disease on radiographic examination, with pulmonary function findings of reduced vital capacity, total lung capacity (measured in five patients), and maximal voluntary ventilation. Five patients had ventilatory failure with carbon dioxide retention; four of these have died and one is close to death. Examination of the thoracic organs in five patients showed minimal or no parenchymal fibrosis in three and less severe involvement of the parenchyma than of the pleura in the remaining two. Neoplasms were suspected in three patients because of extension of the pleural fibrosis into the lung. Two of these patients had pleural uptake of 67-gallium citrate attributable to the inflammatory reaction. With the increasing duration since onset of exposure in the nine million workers who have been exposed to asbestos, as well as in other exposed persons, it is expected that additional cases of ventilatory failure caused by asbestos-induced pleural fibrosis will be encountered.”

If you found any of these studies interesting, please read them in their entirety. We all owe a great deal of thanks to the people who are researching these important issues.

By: Mont Wrobleski

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Monty Wrobleski is the author of this article, for more information please visit the following links Nephrogenic Systemic Fibrosis, Nephrogenic Systemic Fibrosis Lawyer, Mesothelioma Attorneys