Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032273 (pneumoconiosis)
 1,578 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lipid peroxidation parameters, such as malonic dialdehyde and antioxidant defense (superoxide dismutase and catalase activities) were studied in healthy individuals, miners of different occupations, working at mines of different altitudes. The studies showed that increased lipid peroxidation and decreased antioxidant defense are connected with the altitude of work and exposure to the quartz-containing dust combined with hypobaric hypoxia. Malonic dialdehyde, the final toxic product of peroxidation, is accumulated as a result of it. Increased membranous lipid peroxidation results in death and lysis of cells. It becomes the principal pathogenetic component of pneumoconiosis formation and clarifies the mechanism of its early development, comparatively fast progressing, frequency of nodular forms in miners from the high and middle altitudes. That testifies the ability of hypobaric hypoxia to produce silicosis.
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PMID:[The mechanisms of the formation of pneumoconiosis under high-altitude conditions]. 142 41

Activity of purine metabolism enzyme, adenosine deaminase (ADA) in lymphocytes and erythrocytes from patients with pneumoconiosis and chronic bronchitis was determined. ADA activity decrease was found in lymphocytes and erythrocytes for both decreases. The observed decrease of ADA activity indicates that after the long term work in mineral dust industry damage of purine metabolism takes place, that is similar to the disturbance observed under secondary immunodeficiency. Changes in activity of superoxide dismutase and catalase show some decrease of functional activity of anti-radical protection. Therefore the results obtained can be used for the selection of a group with highest risk of predisposition to these diseases.
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PMID:[Changes in adenosine deaminase and antioxidative enzyme activity in patients with lung diseases of dust etiology]. 179 56

We have examined superoxide anion (O2-) release by alveolar inflammatory cells recovered by bronchoalveolar lavage from the lower respiratory tract of 10 healthy nonsmokers and 25 nonsmoking pneumoconiotic patients, 11 with radiographic changes of simple pneumoconiosis (SP) and 14 with changes of progressive massive fibrosis (PMF). Significant increased number of cells was recovered from the lower respiratory tract from both patients with SP or with PMF. Alveolitis was made up predominantly of alveolar macrophages (AM) and an increased percentage of neutrophils in patients with PMF (3.3 +/- 0.7%). O2- release was evaluated using a superoxide dismutase (SOD)-inhibitable lucigenin-dependent chemiluminescence method. Spontaneous O2- generation by alveolar inflammatory cells from pneumoconiotic patients with SP was three to four times greater than that from 10 age-matched, healthy control subjects. O2- release by alveolar inflammatory cells from patients with PMF was dramatically increased when compared with that in patients with SP and with that in control subjects and was observed before and after stimulation by phorbol myristate acetate (PMA) (p less than 0.001). The increased O2- release was not due to a lack of enzyme antioxidant system within AM since intracellular superoxide dismutase was not lower in AM from patients than in AM from control subjects (p less than 0.05). Alteration of DLCO correlated with PMA-induced superoxide release by alveolar inflammatory cells in patients with PMF (p less than 0.05). Our data demonstrate that alveolar inflammatory cells from pneumoconiotic patients with PMF are in the activated state and release more oxygen-reactive species that do those from patients with SP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Superoxide anion generation by alveolar inflammatory cells in simple pneumoconiosis and in progressive massive fibrosis of nonsmoking coal workers. 215 52

Electron spin resonance (ESR) measurements show that grinding of quartz particles in air produces silicon-based (Si. and SiO.) radicals which decay with aging in air. ESR spin trapping measurements provide evidence for the generation of hydroxyl and possibly superoxide radicals from a suspension of fresh quartz particles. The hydroxyl radical generation potential of the fresh quartz particles decreases on storing in ambient air and on the addition of catalase, superoxide dismutase, desferroxamine, or DMSO. Silica-induced lipid peroxidation also decreases on storing the fresh particles in ambient air. These findings suggest that oxygenated radicals play a role in the biochemical mechanism of pneumoconiosis in general and acute silicosis in particular.
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PMID:ESR spin trapping and cytotoxicity investigations of freshly fractured quartz: mechanism of acute silicosis. 216 64

The pneumoconioses are associated with chronic inflammatory processes during which increased amounts of reactive oxygen species are formed in the lower respiratory tract. To characterize the effect(s) of these processes on the defense system against free radicals, we studied 91 individuals with long-term occupational exposure to coal mine dust. Thirty-one subjects were classified with radiological evidence to be pneumoconiotics, while 58 control miners had no pulmonary disorders. We measured antioxidant parameters in red blood cells, considering the latter to reflect the oxidative stress in the lung. Glutathione levels were significantly decreased (p = 0.04) in red blood cells of miners with coal workers' pneumoconiosis with radiograph classification 0/1 to 2/1, while in miners with classification 3/2 to 3/3, the plasma iron concentrations were significantly decreased (p = 0.04). Moreover, some factors of the anti-oxidant system (superoxide dismutase, catalase, glutathione peroxidase) were correlated in the diseased but not in the control miners. Taken together, all data support the role of the erythrocyte as a circulating anti-oxidant carrier and also that changes in red blood cell anti-oxidant factors reflect the oxidative stress imposed by the pneumoconiotic (inflammatory) processes in the lung.
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PMID:Blood anti-oxidant parameters at different stages of pneumoconiosis in coal workers. 235 Nov 20

Occupational exposure to coal mine dust causes coal workers' pneumoconiosis (CWP) and other pulmonary diseases by mechanisms that remain unclear. Because the hydroxyl radicals (.OH) may play an important role in the pathogenesis of CWP, we studied the potential role of bituminous coal mine dust samples for catalyzing the generation of .OH from hydrogen peroxide (H2O2). These coal mine dusts evaluated represented two geographic areas with diversity in CWP prevalence. Electron spin resonance (ESR), with the aid of spin trapping techniques, was used to measure the .OH radical generation. Bituminous coal mine dusts representing the Pittsburgh seam in the eastern United States and Blind Canyon seam in the mid-western United States were used together with a standard coal dust obtained from the National Institute of Standards and Technology, Gaithersburg, MD. All the coal mine dust samples generated varying levels of .OH radicals from H2O2 in the presence of a .OH spin trap 5,5-dimethyl-l-pyrroline-N-oxide (DMPO). .OH radical generation by the coal from H2O2 was effectively inhibited by deferoxamine and catalase, but only partially inhibited by superoxide dismutase. Metal chelators DETAPAC and EDTA enhanced the radical generation. These results indicated that the Fenton reaction is predominantly involved in the generation of .OH radicals from H2O2. The .OH-generating potential of all the coal dusts showed a positive correlation with the surface iron content of coal mine dusts. In addition, the potential to induce lipid peroxidation by the coal samples exhibited a good correlation with the available surface iron. Based on the results presented here, we propose that higher concentrations of surface iron in coal mine dust may be involved in the generation of increased levels of .OH radicals and may play an important role in the development of CWP in different coal mining areas.
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PMID:Hydroxyl radical generation by coal mine dust: possible implication to coal workers' pneumoconiosis (CWP). 789 64

The authors examined indicators of the effect of free radicals (MDA, SOD, GSHPx, selenium) in 20 patients with notified simple silicosis or miner's pneumoconiosis, in 11 patients with complicated silicosis or miner's pneumoconiosis and in 10 patients exposed to fibrogenic dust without an X-ray finding of pneumoconiosis. No statistically significant differences between individual groups were found. Subsequent investigations should be focused on subjects with incipient pneumoconiosis who are not yet entitled to damages.
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PMID:[Free radial activity in patients with pneumoconioses]. 862 54

This study investigated whether differences in the prevalence and severity of coal workers' pneumoconiosis (CWP) between three coal mines could be related to differences in oxidative stress exposure as evaluated in vivo through red-blood-cell antioxidant enzyme activities. Blood samples were obtained from 229 miners selected according to their occupation and their pneumoconiotic status. The following biomarkers were evaluated: erythrocyte catalase, Cu2+/Zn2+ superoxide dismutase (Cu2+/Zn2+ SOD), and glutathione peroxidase activities. Antioxidant enzyme activities did not differ significantly between the group of surface workers in Lorraine and the group of underground miners without CWP in Lorraine and in the other coal mines. Erythrocyte Cu2+/Zn2+ SOD activity was slightly decreased in the group of active underground miners with simple pneumoconiosis as compared with the group of miners without CWP in Nord/Pas-de-Calais. No effect was seen between retired miners at different stages of CWP. Our findings indicate that differences in the prevalence and severity of CWP do not seem to be related to various oxidative activities of coal dust particles, at least as reflected by measurements of antioxidant enzyme activities in circulating erythrocytes in this study.
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PMID:Erythrocyte antioxidant enzyme activities in coal miners from three French regions. 963 82

Previous studies on symptomatic coal miners have shown that alveolar macrophages, recovered by bronchoalveolar lavage (BAL), release excessive amounts of reactive oxygen species (ROS) and inflammatory cytokines. It has been proposed that these secretions may mediate cell injury and initiate the disease process. We hypothesized that acellular bronchoalveolar lavage fluid (BALF) indices in coal miners chronically exposed to coal dust may reflect the status of important homeostatic modulations in the lung that lead to the development of coal workers' pneumoconiosis (CWP). To test this hypothesis, we measured inflammatory status, oxidant burden, antioxidant defenses, cytokines, growth factors, fibronectin, and alpha(1)-antitrypsin (alpha(1)-AT) in the BALF of healthy never-smoker control subjects, never-smoker underground coal miners with negative radiographs (ILO 0/0-1/0), and two miners with moderate changes in the chest radiographs (ILO 2/2). Interestingly, indices of injury and inflammation increased with the progression of disease in coal miners. Antioxidant enzymes, such as catalase, glutathione peroxidase, and superoxide dismutase, showed a 19-fold, 22-fold, and 6-fold increase above control, respectively, in coal miners with category 2/2 CWP. Significant increases in the secretion of IL-1, IL-6, TNF-alpha, TGF-beta, fibronectin, and alpha(1)-AT also were evident in coal miners with disease. This up-regulation of antioxidant defenses and cytokines was not evident in coal miners in the absence of clinically evident radiographic disease. In addition, the concentration of lipid peroxidation by products in the BALF of coal miners without evidence of radiographic disease showed a moderate 3-fold increase, whereas, in coal miners with category 2/2 CWP it showed a 59-fold increase compared to control subjects. These results are in good agreement with our hypothesis that development of CWP and its progression may be correlated with an oxidative stress and up-regulation of cytokines and mediators of growth.
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PMID:Changes in bronchoalveolar lavage indices associated with radiographic classification in coal miners. 1098 13

In miners exposed to coal dusts, coal worker's pneumoconiosis (CWP) can occur. The purpose of the present study is to better understand the relations between coal dust exposure and activities of blood plasma antioxidant enzymes, namely, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation end product malondialdehyde (MDA) concentration in coal workers with early and low grade simple CWP diagnosed by high resolution computed tomography (HRCT). Forty-three coal workers who had profusions of 0/1-2/2 according to ILO 1980 chest X-ray (CXR) classification, 43 coal workers without CWP (control group 1) and 44 healthy subjects (control group 2) who were randomly selected from the population register or recruited from the hospital staff were enrolled. Coal workers were reevaluated by HRCT (Hosoda-Shida classification) due to its higher sensitivity than standard CXR. Then, blood plasma SOD and GSH-Px activities and MDA plasma levels were measured. CWP was found positive in 46 of 89 coal workers by HRCT evaluation. Profusion 0 (P0, CWP not present), profusion 1 (P1, early CWP) and profusion 2 (P2, low grade CWP) were found in 43, 23 and 19 of patients found to have CWP by HRCT, respectively. We had no worker with profusion 3 (P3). Complicated CWP was shown in four of 46 patients and thesecases were excluded as the study was restricted to early and low-grade pneumoconiosis. In respect to the plasma levels of MDA and plasma activities of SOD and GSH-Px, statistically significant differences were found between CWP cases and control groups (p < 0.01, p < 0.01, p < 0.001 respectively). Statistical differences were also obtained for the plasma activities of SOD and GSH-Px and levels of MDA in relation to HRCT profusions (p < 0.05). In conclusion, these findings suggest an oxidative stress due to increased free radicals and reactive oxygen metabolite production in early stages and low grades of simple CWP diagnosed by HRCT.
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PMID:Antioxidant response at early stages and low grades of simple coal worker's pneumoconiosis diagnosed by high resolution computed tomography. 1557 61


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