Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034067 (emphysema)
 11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prolonged exposure to formaldehyde induces in the rabbit lung reactional and dystrophic changes involving the intrapulmonary bronchi, the bronchioli and the lung tissue. These changes are represented by bronchial cell hyperplasia with hypermucigenesis, extrusion of bronchial cells, bronchiolar hypermucigenesis, parcellary squamous metaplasia or necrobiosis of epithelia, thickening of bronchial and bronchiolar walls by subepithelial cell accumulations, destruction of musculo-elastic structures with stenosis or ectasia; the vascular reactions are hyperhaemic and proliferative with an obstructive and fibrous tendency; the parenchymal lesions are atelectasias, intralobular emphysema, and cellular thickening of alveolar walls and interlobular areas. The acid phosphatase, Tween-60-esterase, naphthol-AS-D-acetate-esterase, proline-oxidase and hydroxyproline-2-epimerase activities are increasing, while the leucyl-aminopeptidase and beta-glucuronidase ones are decreasing. The qualitative observations are completed and sustained by quanitative studies of mucous cell kinetics, of cell accumulations and differentiations.
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PMID:Experimental chronic obstructive lung disease. I. Bronchopulmonary changes induced in rabbits by prolonged exposure to formaldehyde. 15 Dec 23

The occurrence of emphysema in people deficient in alpha1-antitrypsin and the production of emphysema in experimental animals with elastolytic enzymes suggest proteolysis as a mechanism for the development of emphysema. To investigate the possible role of pulmonary alveolar macrophages in the pathogenesis of emphysema, we measured elastase, acid protease, and elastase-like esterase activities in macrophages from patients with chronic obstructive lung disease and attempted to correlate the level of enzyme activity with the severity of pulmonary function abnormality measured in these patients. Compared to values for cigarette smokers with normal pulmonary function, these macrophage enzyme activities were not increased in patients with chronic obstructive lung disease, and there was no correlation of high elastase activity with more severe degrees of pulmonary function abnormality. These findings lead us to believe that the absolute level of proteolytic enzymes in pulmonary alveolar macrophages is not in itself a determinant of emphysema.
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PMID:Human alveolar macrophage proteolytic enzyme activities in chronic obstructive pulmonary disease. Lack of correlation with functional abnormalities. 63 Sep 33

Proteolysis (or more specifically, elastolysis) of the lung may be involved in the pathogenesis of pulmonary emphysema. To investigate the human alveolar macrophage as a potential mediator of lung damage, elastase-like esterase and protease activity was determined in these cells as well as in alveolar lavage fluid and in peripheral blood leukocytes. Bronchoalveolar lavage was used to obtain alveolar cells and fluid in normal volunteers who were divided into two groups according to cigarette smoking history, nonsmokers and smokers. Results of these studies revealed that human alveolar macrophages possess a high activity of both elastase-like esterase and protease. Furthermore, the alveolar macrophages of cigarette smokers has a significantly greater elastase-like esterase and protease activity than those of nonsmokers. When the 4- to 5-fold increase in the number of macrophages found cigaretts smokers is taken into account there was approximately 10 times more elastase-like esterase activity and 18 times more protease activity within macrophages in the alveolar spaces of cigarette smokers' lungs. This makes the alveolar macrophage a poten potential source of proteolytic enzymes in man.
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PMID:Comparison of proteolytic enzyme activity in pulmonary alveolar macrophages and blood leukocytes in smokers and nonsmokers. 113 Jul 51

Studies were designed to explore the possibility that human polymorphonuclear leukocyte granule constituents in addition to elastase (HLE) had the potential to cause emphysema. A two-step purification of three serine proteinases was developed. Granule extract proteins were initially separated by dye-ligand affinity chromatography. Fractions eluted were divided into four pools. Hamsters were given a single intratracheal instillation of saline +/- 0.1 mg protein of each pool. While pool 2 contained HLE and cathepsin G, the most dramatic bullous emphysema developed in animals treated with pool 4. The esterase from pool 4, designated proteinase 3 (PR-3) was purified, characterized in vitro, and tested for its ability to cause emphysema. PR-3 is a neutral serine proteinase with isoenzyme forms. Its ability to degrade elastin at pH 6.5 is slightly greater than that of HLE, but it is less active than HLE at pH 7.4 or 8.9. PR-3 has weak activity against azocasein. Its ability to degrade hemoglobin is intermediate to that of HLE and cathepsin G at pH 7.4. PR-3 has no activity against chromogenic substrates specific for HLE or cathepsin G. Its pI is substantially less than HLE or cathepsin G. It is also immunologically distinct from HLE. It induces emphysema in hamsters commensurate with that of HLE. We conclude that PR-3 may be important in the pathogenesis of human emphysema.
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PMID:Proteinase 3. A distinct human polymorphonuclear leukocyte proteinase that produces emphysema in hamsters. 319 60

Considerable progress has been made in the localization of chemical substances within the gas-exchange zones of vertebrate lungs since cytochemical techniques suitable for use with the electron microscope have been developed. The light microscope, an instrument with an effective resolution limit of about 0.2 micron, is ill-suited for studying regions such as these where small tissue elements are arranged in a complex manner. A wide range of acid hydrolases have been detected in the vacuoles and dense bodies of alveolar macrophages by means of cytochemical techniques. The enzymes demonstrated in this way include acid phosphatase, aryl sulphatase, cathepsin D, beta-glucuronidase, acetyl glucosaminidase, nonspecific esterase, dipeptidyl peptidase II and dipeptidyl peptidase IV. Such enzymes are, of course, to be expected in the lysosomes of cells which have a primary phagocytic role. Nevertheless, it must be confessed that very little is yet known about the actual mechanism of phagocytosis or of the fate of the digested material. It is fortunate, however, that some of the tools which are likely to be of value in research on these aspects of macrophage function are currently being developed. Of particular interest in this connection are the immunocytochemical techniques which permit the localization of surface-associated antigens and intracellular contractile proteins. It must be emphasized that phagocytosis is not the only function of macrophages in the gas-exchange zone of the lung. These cells are thought to be involved in the presentation of exogenous antigenic material to the reactive cells of the lymphoid system. Recent research has also indicated that mammalian alveolar macrophages synthesize a diverse range of substances. Furthermore, the elastases associated with pulmonary macrophages are now thought to be involved in the pathogenesis of emphysema. All of the above-mentioned activities are of great biological and clinical significance and, consequently, merit the cytochemists' attention in future. The epithelial lining of the greater part of the pulmonary gas-exchange area is composed of type I pneumonocytes. In terms of ultrastructure, these are very specialized cells; their extensive and highly-attenuated cytoplasmic processes form the outer layer of the air-blood barrier. No special carrier systems have been identified within type I pneumonocytes and this is in keeping with the claims that oxygen is transferred across the alveolar tissue barrier by a process of simple diffusion. Type II pneumonocytes, in contrast, have considerable metabolic activity.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Cytochemistry of the gas-exchange area in vertebrate lungs. 355 66

Proteases have a wide range of functions: digestion (pancreatic proteases), protein catabolism (lysosomal proteases), blood coagulation, immune defences (complement), cellular division and proliferation, generation of biologically active oligopeptides (kinins, hormones) from inactive polypeptide precursors, inactivation of these oligopeptides, etc. The body protects itself against its own proteases, either by confining them to a given compartment (lysosome), by synthesising them in the form of inactive precursors (trypsinogen, prothrombin, etc.), or by synthesising proteins with an antiprotease activity. Any disturbance in one of the elements of this protective system may lead to severe pathological consequences: acute hemorrhagic pancreatitis with shock, coagulation disturbances (deficient hepatic synthesis of coagulation factors, congenital antithrombin III deficiency), angioneurotic oedema (congenital deficiency of C'l esterase inhibitor) pulmonary emphysema (local secretion of leukocyte elastase, congenital deficiency of alpha a-antitrypsin).
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PMID:[Problems in intensive care posed by imbalance in the protease--protease inhibitor system]. 611 Dec 72

The influence of T. canis larvae migration on the lung tissue of paratenic host (inbred mice, strain C57BL6/J) was evaluated. First macroscopic manifestation was already observed on day 2 in the time of the highest larval recovery. Larvae entering the lung tissue caused numerous small extravasations. Their migration from the lungs was manifested from day 6 with an increase in the number and extent of extravasations. The lungs assumed tiger spot appearance (Fig. 1). The larval recovery was decreasing. From day 14 the expressiveness of macroscopic changes was declining. Areas of emphysema and atelectasis were observed on the lungs. The genesis and the process of elimination of extravasations were studied histologically. In the first period, the primary extravasations, caused by larvae migrating to the lung tissue (Fig. 2), were eliminated by monocytes and eosinophilic granulocytes in increasing numbers (Fig. 3). Immunohistochemically macrophages and dendritic cells were already observed in the lungs on day 1 (Fig. 4). Acid phosphatase activity was increasing from day 1 and its highest level was observed on day 84. Alkaline phosphatase activity on days 2-4 was not observed in the areas of extravasations although within the larvae themselves it was high. The extravasations of the second period (caused by larval migration from the lungs) from day 5-6 were eliminated with humoral monocytes and cells of perivascular and peribronchial tissue. Eosinophils were not active in this process. Strong exudation was observed here. The humoral part of extravasations was eliminated primarily. The cytoplasmic volume of activated cells was enlarging. Multinuclear symplasms were originated (Fig. 5). The activities of alkaline phosphatase and nonspecific esterase were increased. Macrophages and dendritic cells were still present in high numbers and from day 14 aggregations of T and B lymphocytes were observed (Fig. 6). Reparative processes were frequently observed on the blood vessels altered by the leaving larvae (Fig. 7). Changes on the lungs caused by migration of larvae always ended in functional regeneration of the lung tissue. On the other hand dead larvae stimulated proliferative forms of inflammatory reactions which led to induration (Fig. 8).
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PMID:[Changes in the lungs in mice caused by migration of Toxocara canis larvae]. 786 76