Search PubMed⌕ Search

Biomedical subjects

W Hornebeck

Publications and source records attributed to W Hornebeck.

At least 127 records · Page 7Linked to original sources
PubMed1983

Elastase-type activity of human serum. Its variation in chronic obstructive lung diseases and atherosclerosis.

Human serum was found to contain enzyme activities hydrolyzing succinyl trialanine paranitroanilide and 3H-kappa-elastin Sepharose substrates. Both types of activities could be partly abolished by serine active site titrants (phenylmethanesulfonylfluoride, diisopropylphosphorofluoridate) and partly by neutral chelating agents (EDTA; 1-10-phenanthroline). The combination of phenylmethanesulfonylfluoride and EDTA gave a complete inhibition of human serum elastase-type activities indicating the presence of at least two different types of elastases (serine and metalloproteases) in human serum. In nonsmokers, the average serum elastase-type activity on succinyl trialanine paranitroanilide was found equal to 78.1 ng/ml porcine pancreatic elastase equivalents and on 3H-kappa-elastin sepharose beads equal to 688.8 ng/ml. No statistically significant differences were observed in elastase levels in the sera of individuals presenting clinical symptoms of atherosclerosis. The sera of patients suffering from chronic obstructive lung diseases contained, however, higher amounts of elastase-type activities, respectively equal to 237.2 ng/ml on succinyl trialanine paranitroanilide and 1,096 ng/ml on 3H-kappa-elastin Sepharose beads and was quantitatively significant when compared with control subjects.

Adult↗
PubMed1982

Isolation and partial characterization of an elastase-type protease in human vulva fibroblasts: its possible involvement in vulvar elastic tissue destruction of patients with lichen sclerosus et atrophicus.

A complete disappearance of orcein positive material was observed in the superficial dermis of patients suffering from Lichen sclerosus et atrophicus. An elastase-type protease was isolated and partially purified from Triton X-100 extracts of human vulvar fibroblasts by gel permeation chromatography. It presents the characteristics of a metalloenzyme hydrolyzing Succinoyl-tri-alanine paranitroanilide maximally at pH 8.0 and is also active towards insoluble elastin. When partially purified enzyme is directly applied on to rabbit skin sections or when injected intradermally to young rabbits, it produces appreciable degradation of elastic fibers. The involvement of this protease in the disappearance of elastic fibers in Lichen sclerosus et atrophicus is postulated.

Adult↗
PubMed1982

Variation of elastase-type protease activity and elastin biosynthesis in rabbit aorta induced by cholesterol diet and immunization with elastin peptides.

Elastase-type proteases were shown to be produced by arterial smooth muscle cells and fibroblasts in culture and are probably involved in the development of the arterio-atherosclerotic process (1-4). The present investigation was aimed at the quantitative determination of the elastase-type enzyme activity in the aortas of rabbits submitted to two different athero-arteriosclerosis inducing treatments: high cholesterol diet and immunization with kappa-elastin peptides. Simultaneously we determined the incorporation of 14C-lysine in cross-linked elastin peptides by the surviving aorta extracts, determined with a synthetic substrate (Suc-(Ala)3-pNA) increased two fold after 1.5 month cholesterol diet, and three fold after 8 weeks of immunization with kappa-elastin in complete Freund's adjuvant. The incorporation of 14C-lysine in cross-linked elastin slightly increased (+20%) in cholesterol-fed aorta-explants and strongly decreased (-65%) in the immunized aorta-explants, on a DNA basis. These results confirm our contention that atherogenic stimuli produce an increase of elastase-type enzyme activity in the arterial wall. This increase appears to be correlated with elastic fibers degradation. It may also be accompanied by a decrease of elastin biosynthesis as in the kappa-elastin induced immuno-arteriosclerosis model.

Animals↗
PubMed1982

Effect of different elastase inhibitors on leukocyte elastase pre-adsorbed to elastin.

The effect of three elastase inhibitors (MeO-Suc-Ala-Ala-Pro-Val-CH2Cl, eglin c and alpha 1-proteinase inhibitor) on the hydrolysis of [3H]elastin was determined. The low-molecular mass inhibitors inactivated elastase nearly completely, regardless of whether or not the enzyme was adsorbed to its substrate elastin prior to the addition of the inhibitors. In contrast, elastase preadsorbed to elastin was much less sensitive to the inhibitory effect of alpha 1-proteinase inhibitor than the free elastase.

Elastin↗
PubMed1981

[A simple method for detection of functional and genetics alpha-1-antitrypsin deficiencies of human serum (author's transl)].

Insoluble elastin immobilised in Agar plates was used as substrate to quantitate the elastase inhibitory capacity of human sera. This technique was found valuable to evaluate the genetic deficiency of alpha-1-antitrypsin (Z phenotypes) and also the functional loss of the elastase inhibitory capacity in smokers. A significant decrease of elastase inhibitory capacity was demonstrated in the sera of smokers between 40 and 80 years of age, as compared to non smokers of the same age. This method may be useful for the evaluation of patients suffering from elastic tissue diseases (emphysema, arteriosclerosis).

Elastin↗
PubMed1981

Studies on elastic tissue of aorta in aortic dissections and Marfan syndrome.

Insoluble elastins were isolated from control and aneurytic aortas by a sequential extraction procedure involving the use of purified collagenase. Marked differences in amino acid analyses and susceptibilities to pancreatic elastase were observed between normal and pathological samples. The incorporation of either 14C-lysine or 14C-glucosamine into proteins of the vessel wall was also studied. In addition, high amounts of elastase-type activity was extractable from pathological aorta specimens which may contribute significantly to the loss of elastic tissue evidenced by ultra-structural studies and confirmed by the biochemical technics. We propose therefore that increased elastase-type protease activity in these pathological aortas does significantly contribute to the weakening of the aortic wall and also may well be the main cause of the rupture of aneurysms observed occasionally.

Adult↗
PubMed1980

Interaction of dinitrophenyl-pepstatins with human cathepsin D and with anti-dinitrophenyl antibody. Development of potential reagents for the localization in vivo of active proteinases at sites of tissue injury.

Extracellular cathepsin D has been observed by various cytochemical methods at sites of tissue injury. However, the role of this enzyme in connective tissue matrix degradation is uncertain because there are no histochemical methods for determining whether or not the cathepsin D is active at such sites in living tissues. We considered that the combined use of a labelled tight-binding inhibitor with immunoprecipitation of the enzymes might overcome this problem. We have explored the application of derivatives of the inhibitor pepstatin, as only active cathepsin D binds pepstatin tightly. A series of N-pepstatinyl-N'-dinitrophenyl-alpha, omega-diaminoalkanes were synthesized with alkyl-chain lengths of two, four and six carbon atoms. These compounds were tight-binding inhibitors of human cathepsin D. In fluorescence-quenching titrations the dinitrophenyl groups were also fully available to bind high-affinity anti-dinitrophenyl antibody. It was shown by immunodiffusion in gels and by gel permeation chromatography that N-pepstatinyl-N'-dinitrophenyl-1,6-diaminohexane was a bifunction inhibitor able to bind cathepsin D and anti-dinitrophenyl antibody at the same time.

Antibody Affinity↗
PubMed1980

Isolation and partial characterization of an elastase-type enzyme from human arterial wall by lima-bean trypsin inhibitor affinity chromatography.

A serine protease active on insoluble elastin at neutral pH has been isolated from human aortic media employing a Lima-bean trypsin inhibitor - Sepharose column. It is also hydrolyzed Suc (Ala)3 pna and casein but was found inactive against Benzoyl-Tyr-pna and Benzoyl-Arg-pna. Its apparent molecular weight as determined by SDS-PAGE was 22,300 Daltons. It differs from other elastases of human origin (human pancreatic elastase-1, human pancreatic elastase-2, human leucocyte elastase) on the basis of amino-acid composition and immunological specificity.

Amino Acids↗
PubMed1978

Partial characterisation of an elastase-like enzyme secreted by human and monkey alveolar macrophages.

An elastinolytic activity on soluble and insoluble elastin has been demonstrated in the culture medium of human and monkey alveolar macrophages. This activity is potentiated by latex particles in the medium. An enzyme resembling some other elastases was partially purified and characterised. It differs from other elastases in its affinity for elastin and a synthetic substrate, its susceptibility to various kinds of inhibitors and by its metal ion requirement.

Animals↗
PubMed1978

[Simple methods for the quantification of elastase and its inhibitors in human sera (author's transl)].

Two methods for measuring the elastase activity and the elastase inhibitory capacity of sera or other tissue extracts are described. The elastase inhibitory capacity of 40 human sera is determined using highly purified insoluble elastin in a gelified medium and this value is correlated to the alpha1-antitrypsin concentrations of these sera quantified by radial immunodiffusion. The elastase activity of these sera were determined on high molecular weight soluble kappaelastin peptides immobilized in a gelified medium and we have found a strong dispersion of the individual values. The elastase activity is not correlated either with the inhibitory capacity, the alpha1-antitrypsin or alphai-macroglobulin concentrations of these sera. The sensitivity, specificity and simplicity of these methods render them useful for their application to clinical investigations.

Elastin↗