1,721,184 research outputs found
Detection of elastase activity with a zymogram method after isoelectric focusing in polyacrylamide gel
No full textA zymogram method for detecting elastase activity following isoelectric focusing in polyacrylamide gel is described. After enzyme activity has been visualized, the gel itself is available for protein staining and for analysis in sodium dodecyl sulfate-polyacrylamide gel electrophoresis in second dimension. The zymogram method is suitable for detecting microgram amounts of elastase and has one step only. It can be used with the purified enzyme as well as with crude extracts of tissue containing elastases showing activity toward succinyl-(Ala)3-p-nitroanilide. By this method a major component of elastase in both porcine and rat pancreas was detected. In addition, two forms of elastase with isoelectric points of 8.2 and 8.8, respectively, were identified in rat leukocyte extracts
Isolamento di attività elastolitiche nell'aorta, nel pancreas, nei granulociti e nelle piastrine di ratto. Confronto tra alcune delle loro proprietà chimico -fisiche ed enzimatiche
No full textPurification and partial characterization of elastase activity from rat alveolar and peritoneal macrophages
No full textMacrophage elastase was purified from conditioned media from alveolar and thioglycollate-elicited peritoneal macrophages. The enzyme was purified to apparent electrophoretic homogeneity by preparative isoelectric focusing after a purification step consisting of low ionic strength dialysis and sequential batch fractionation on DEAE-Sephadex A-50. The proteinase activities isolated from alveolar and peritoneal macrophages showed the same physical and biochemical properties. This fact suggests that the same enzyme activity is present in rat macrophages of two different anatomical sites. The molecular weight and isoelectric point of the enzyme were estimated to be 22,500 and 8.3, respectively. The enzyme, characterized as a metallo proteinase, had elastolytic activity, as well as activity toward Suc-(Ala)3-NA. It is inhibited by o-phenanthroline, chicken ovoinhibitor, and EDTA, but not by phenylmethylsulfonyl fluoride or soybean trypsin inhibitor. The macrophage enzyme possesses biochemical and biophysical properties different from the rat pancreatic and granulocyte elastases (which are serine proteinases), and from the metallo proteinase with elastolytic activity isolated from rat platelets
Isolation and partial characterization of rat elastolytic enzymes from various cells and tissues
No full textDifferent elastolytic enzymes were isolated from rat aorta and platelets, as well as from granulocyte and pancreatic extracts. The active fractions were purified to electrophoretic apparent homogeneity by precipitation with ammonium sulfate, sequential batch fractionation on DEAE-Sephadex A-50, and finally by isoelectric focusing (IF) on Sephadex G-75 Superfine. The molecular weight and the isoelectric point of the isolated enzymes were estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by analytical IF, respectively. All the enzymes have elastolytic activity as well as activity toward Suc-(Ala)3-NA. The inhibition profile of the different isolated enzymes toward various inhibitors indicates that aortic, pancreatic, and granulocyte enzymes all belong to the group of serine proteinases, unlike the platelet elastase which is a metalloproteinase
Isolamento di attività elastolitiche nell'aorta, nel pancreas, nei granulociti e nelle piastrine di ratto.Confronto tra alcune delle loro proprietà chimico-fisiche ed enzimatiche
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Outlook from the soil perspective of urban expansion and food security
Full text linkThe use of soil as support for built-up areas represents only one of its several functions. Farmlands at the fringe of conurbations have more chance of being converted into built-up areas due to the favourable topography and the accessibility to existing infrastructure, being in the vicinity of urban areas. We analysed the global land-take during the period 2000–2014. The data are based on a global dataset describing the spatial evolution of human settlements using the Global Human Settlement Layer, which was derived from Landsat images collected in 1975, 1990, 2000 and 2014. Although the global land-take represents roughly 0.1% of the global terrestrial Earth, it affects 1% of the naturally fertile soils, according to the proposed Soil Productivity Indexes (SPI), based upon the potential soil productivity, calculated on the basis of the Harmonized World Soil Database. We have found that, few large conurbations develop on potentially high productive soil, while scarcely productive soils sustain the expansion of several megalopolises. On a global scale and through the centuries, considered comparatively as individual overall age of settlements, a trend between the intrinsic quality of the soils and its use for settlement purposes as major competitor, was not observed
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