Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Most measures taken to prevent atherosclerosis still aim at lowering the cholesterol content of the plasma lipoproteins by dietary and pharmacological means. This approach has only proved successful to a limited extent. Diseases secondary to atherosclerosis are still the commonest cause of death in western industrialized countries. As all metabolic processes are regulated by opposing processes of equilibrium, i.e. by processes directed towards performance and recovery, we asked ourselves whether the fatty degeneration and sclerosis of the arteries could be causally related to a continuous dysregulation of these processes. We consider this to be the case, with a continuous deficiency of glycosaminoglycans (heparin, heparinoids) on the endothelial surface of the vessels. Numerous studies indicate that in the case of thinning of the anionic glycosaminoglycan film on the endothelial surface, the lipoprotein-lipase and antithrombin III activity induced by heparin is reduced, as result of which hyperlipoproteinaemia and increased tendency to thrombosis can only by compensated for to an inadequate extent. The formation of glycosaminoglycans is a characteristic of all mesenchymal cells, whereby the exogenous introduction of glycosaminoglycans into the extracellular space is of decisive importance for adequate glycosaminoglycan synthesis. Since Engelberg reported outstanding results obtained with heparin injections in the prevention and treatment of atherosclerotic disorders of the cardiac circulation, we considered it appropriate to use the well-proven dietary supplement of glycosaminoglycans in rheumatology, in the treatment of arthrosis, as well as in the prevention and treatment of atherosclerosis.
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PMID:The pathogenesis and prevention of atherosclerosis. 895 6

Polycaprolactone is susceptible to enzymatic biodegradation via ester bond cleavage. This study examined the susceptibility of Resilon, a polycaprolactone-based root filling material to enzymatic hydrolysis. Resilon, gutta-percha, and polycaprolactone disks, prepared by compression molding, were incubated in phosphate-buffered saline, lipase PS or cholesterol esterase at 37 degrees C for 96 h. They were retrieved at different time intervals for gravimetric analysis and scanning electron microscopy. The materials exhibited slight weight gains when incubated in phosphate-buffered saline that can be attributed to water sorption. Gutta-percha showed similar weight gains in the two enzymes. Conversely, Resilon and polycaprolactone exhibited extensive surface thinning and weight losses after incubation in lipase PS and cholesterol esterase. Glass filler particles in Resilon were exposed following surface dissolution of the polymer matrix, creating rough surface topography. Biodegradation of Resilon by bacterial and salivary enzymes warrants further investigation of their activities using cultures of endodontically relevant microbes and human saliva extracts.
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PMID:Susceptibility of a polycaprolactone-based root canal filling material to degradation. II. Gravimetric evaluation of enzymatic hydrolysis. 1618 53

The use of Pickering emulsions for biocatalytical applications has recently received increased attention in cases where hydrophobic reactants are involved. For process applications, knowledge of the emulsion's rheology is crucial for the fluid dynamical design of equipment and selection of operating conditions. Colloidal silica nanoparticle stabilized Pickering emulsions usually exhibit shear-thinning behavior caused by a complex particle-particle network. While this has been observed by many authors, no publication has yet dealt with the rheology of silica nanoparticle stabilized Pickering emulsions containing enzymes. Thus, the aim of this study was to investigate the impact of the commonly used biocatalyst lipase (type and concentration), the dispersed phase volume fraction and the silica particle concentration on the rheological behavior of water-in-oil Pickering emulsions. For this purpose, the impact of the named parameters on the viscosity curves were measured. Lipases reduced the viscosities and transferred the rheological behavior from shear-thinning to Newtonian, which might be due to interactions of the lipase molecules via the formation of intermolecular disulfide bonds, which disturb the hydrogen-bond based silica particle-particle network. However, by increasing the dispersed phase volume fraction or the silica particle concentration the rheological behavior of emulsions became again shear-thinning. This work will help to produce bioactive Pickering emulsions with tailor-made characteristics.
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PMID:The impact of lipases on the rheological behavior of colloidal silica nanoparticle stabilized Pickering emulsions for biocatalytical applications. 3173 92