Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0037116 (silicosis)
 1,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report about the release of a soluble mediator(s) from cultured human monocytes/macrophages after exposure to quartz dust DQ12 or coal mine dust TF-1. This mediator(s) activates isolated human polymorphonuclear granulocytes (PMN) to generation of free oxygen radicals. The strong and long-lasting production of reactive oxygen species (ROS), especially of superoxide anion, was measured as lucigenin dependent chemiluminescence (CL). Studies of mediator exposed PMN with the NBT-test (nitroblue-tetrazolium test) also demonstrated the strong activation of PMN. Electromicroscopical studies of mediator exposed PMN showed strong chemotactic changes in a time dependent manner and suggested the release of lysosomal products. According to these properties we called the mediator(s) "granulocyte activating mediator(s)" (GRAM). Biochemical characterisation indicated a protein nature of GRAM. High pressure liquid chromatography (HPLC) gel-filtration suggested that two molecules or two fragments of one molecule with a m.w. of about 20 kda and just below 10 kda resp. were responsible for the observed effects. PMN are potent inflammatory cells, which are known to immigrate in the lung tissue, especially in the early phases of silicosis. ROS released by activated PMN can act tissue destroying, mutagenic and are probably involved in collagene synthesis by regulation of activity of prolylhydroxylase. Mediator induced release of ROS seems to be an important event in development of lung fibrosis and presents a new mechanism of quartz dust and coal mine dust fibrogenicity.
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PMID:Generation of free oxygen radicals from human polymorphonuclear granulocytes by cytokines from human mononuclear cells, treated with quartz dust DQ12 or coal mine dust TF-1--new aspects in pathogenesis of pneumoconiosis. 285 23

The functional capacity of neutrophils was studied using the NBT test in 68 patients with silicosis in various evolutive stages, comparatively with a group of 35 controls. The NBT test showed an initial increase of nonspecific cellular reactivity which decreased as the disease evolved. The results in the control group showed 9 +/- 5% NBT positive neutrophils. The highest proportion of NBT positive neutrophils (17.6 +/- 2.3, p < or = 0.05) was found in stage I of the disease and then decreased gradually with the evolution of the disease. The proportion of NBT positive neutrophils may be considered as a biochemical marker of neutrophil functionality.
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PMID:Demonstration of the neutrophil granulocyte functional capacity in silicosis, using the NBT test. 853 55