Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.4 (chondroitinase)
 2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proteoglycans were identified and localized histochemically and ultrastructurally in normal and hyperplastic arterial intimas in nonhuman primates (Macaca nemestrina). These regions were consistently more alcianophilic than the adjacent medial layers and this alcianophilia was absent after treatment with glycosaminoglycan-degradative enzymes. Ultrastructurally, the intimal intercellular matrix consisted of numerous, irregularly shaped, 200-500-A diameter granules possessing 30--60-A diameter filamentous projections, and these granules were dispersed between collagen and elastic fibers. The granules exhibited a marked affinity for ruthenium red and were interconnected via their filamentous projections. The ruthenium red-positive granules were intimately associated with the plasma membrane of intimal smooth muscle cells and attached to collagen fibrils and elastic fibers. The matrix granules were completely removed after testicular hyaluronidase or chondroitinase ABC digestion but only partially removed after leech hyaluronidase treatment. These results suggest that the matrix granules contain some hyaluronic acid and one or more isomers of chondroitin sulfate. In addition to the large ruthenium red-positive matrix granules, a smaller class of ruthenium red-positive granule (100--200-A diameter) was present within the basement membranes beneath the endothelium and surrounding the smooth muscle cells. Ruthenium red also exhibited an affinity for the surface coat of the smooth muscle cells. The potential importance of proteoglycans in arterial intimal hyperplasia is discussed.
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PMID:Proteoglycans in primate arteries. I. Ultrastructural localization and distribution in the intima. 5 34

Diseased skin of dogs was stained using the critical electrolyte concentration-Alcian Blue method, PAS methods, and the high iron diamine technique. Digestion with testicular hyaluronidase and chondroitinase was also used to evaluate the staining results. Diseased skin exhibits a tendency for the glycosaminoglycans to revert to the condition seen in juvenile normal skin: epidermal glycoprotein content falls, total glycosaminoglycan content and the proportion undigested by hyaluronidase rises, and sulphation falls. In collagen, both hyaluronidase-stable material and sulphation increase, but follicle basement membrane does not show this trend towards the juvenile state.
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PMID:Glycosaminoglycan staining in diseasesed dog skin. 6 Nov 90

The proteoglycans of cartilage are complex molecules in which chondroitin sulphate and keratan sulphate chains are covalently linked to a protein core, forming a polydisperse population of proteoglycan monomers. By interaction with hyaluronic acid and link proteins, the monomers form large macromolecular complexes. In vivo the proteoglycans mainly occur in such aggregates. In the electron microsope, the cartilaginous matrix can be seen to be made up of thin collagen fibrils and polygonal granules about 10-50 nm in diameter Addition of the polyvalent cationic dye Ruthenium Red to glutaraldehyde and osmium tetroxide fixatives yields a dense selective staining of the matrix granules. Following a short digestion of cartilage slices with either of the chondroitin sulphate-degrading enzymes hyaluronidase and chondroitinase or with the proteolytic enzyme papain, the matrix granules were few in number or completely absent and the proteoglycan content, measured as hexosamine, decreased by up to 90%. Similarly, extraction of the cartilage with 4 M guanidine-HCl removed all matrix granules and most of the proteoglycans. From these findings, it can be concluded that the matrix granules represent proteoglycans, most probably in aggregate form, and that Ruthenium Red staining may be used to study the distribution of these macromolecules in thin sections. As a complement to chemical studies on proteoglycan structure, it is also possible to observe and measure individual molecules in the electron microscope after spreading them into a monomolecular layer with cytochrome c. This technique has been applied in investigations on proteoglycans isolated from bovine nasal cartilage and other hyaline cartilages. The molecules in the monomer fractions appeared as an extended central core filament to which about 25--30 side-chain filaments were attached at various intervals. The core filament, averaging about 300 nm in length, was interpreted as representing the polysaccharide binding part of the protein core and the side-chain filaments, averaging about 45 nm in length, as representing the clusters of chondroitin sulphate chains. Statistical treatment of the collected data indicated that no distinct subpopulations existed within the monomer fractions. The electron microscopic results correlated well with chemical data for the corresponding fractions and together with recent observations on various aggregate fractions strongly support present concepts of proteoglycan structure.
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PMID:Electron microscopy of cartilage proteoglycans. 6 24

The ultrastructural identification and characterization of lung proteoglycans was studied using the polycationic dye, ruthenium red. Treating lung parenchyma with the detergent Triton X-100 increased epithelial permeability and allowed the dye to penetrate alveolar walls and stain the alveolar basement membrane and lung collagen. Ruthenium red stained numerous 10- to 40-nm granules concentrated at the lamina surface of basement membrane and attached to the major doublet collagen band. The granules attached to collagen were digested by chondroitinase ABC and papain, indicating that they represent proteoglycan aggregates containing chondroitin or dermatan sulfate. Granules observed on the alveolar basement membrane were resistant to digestion by collagenase and by all glycosidases, suggesting that heparin or heparan sulfate is the predominant glycosaminoglycan in epithelial basement membrane. Ruthenium red in association with tannic acid also stained a fine network of 3- to 10-nm filaments in which collagen was enmeshed, forming the interfibrillar matrix. This network was resistant to collagenase and glycosidase digestion but was removed after papain digestion, suggesting that it was a protein or glycoprotein that did not contain glycosaminoglycans. These methods have allowed visualization of lung proteoglycans and have identified a structure that does not contain glycosaminoglycan that is intimately associated with collagen. This technique can now be applied to explore the potential role of proteoglycans in lung development and in restructuring the lung in various disease states.
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PMID:Ultrastructural localization and characterization of proteoglycans in the pulmonary alveolus. 9 9

Electron microscopy of ruthenium red stained bovine aorta before and after chondroitinase digestion demonstrates proteoglycans on and between collagen fibrils. The collagen-associated proteoglycans include a proteoglycan previously purified from this tissue as demonstrated by immunocytochemistry and are extractable with high molar guanidine HC1. In loci rich in proteoglycans such as areas of turbulent flow in calves, more proteoglycan can be demonstrated morphologically, and these molecules also coat elastin.
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PMID:The ground substance of the arterial wall. Part 2. Electron-microscopic studies. 13 92

The sulfated proteoglycans synthesized by definitive chondroblasts in cultured 10-day chick vertebral or epiphyseal cartilages were characterized by their sedimentation profile in a sucrose gradient and their susceptibility to chondroitinase ABC (EC 4.2.2.4; chondroitin ABC lyase). These sulfated proteoglycans were indistinguishable from those synthesized by definitive chondroblasts that emerge from older cultures of somites plus notochord or in older cultures of limb buds. The sulfated proteoglycans of these definitive chondroblasts are readily distinguished from those synthesized by their mother cells, the presumptive chondroblasts, or those synthesized by dedifferentiated or bromodeoxyuridine-suppressed chondroblasts. However, the sulfated proteoglycans synthesized by presumptive chondroblasts or by dedifferentiated or bromodeoxyuridine-suppressed chondroblasts cannot be dintinguished by these techniques from those synthesized by (i) blastodisc cells, (ii) fibroblasts, (iii) spinal cord cells, or (iv) skeletal, cardiac, or smooth muscle cells. Addition of glycosaminoglycans or collagen to the medium did not induce somite or limb presumptive chondroblasts to synthesize the chondroblast-unique sulfated proteoglycans. Cells moving from the presumptive chondroblast compartment into the chondroblast compartment acquire not only the option to initiate the synthesis of chondroblast-unique collagen chains, but also the capacity to synthesize chondroblast-unique sulfated proteoglycans.
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PMID:Differences among sulfated proteoglycans synthesized in nonchondrogenic cells, presumptive chondroblasts, and chondroblasts. 13 59

Histological aspects of cervical ripening were studied on the human uterine cervix during pregnancy. Cervical specimens were taken from 25 cases of cervical laceration of primiparous women immediately after delivery, 8 primiparous women whose cervixes opened 2-3 cm, and 5 cesarean-sectioned women with unripeness of cervix. The following histochemical techniques were used: alcian blue, azure A, hyaluronidase digestion, and chondroitinase ABC digestion. The collagen bundles disintegrated into fine fibers and also underwent quantitative changes during the ripening process of the cervix. The number of connective tissue cells was increased during pregnancy, but that of mast cells was decreased. In late pregnancy, acid mucopolysaccharides in the cervical ground substance were found to increase.
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PMID:Histological aspects of cervical ripening. 13 67

Reconstituted, acid-extracted collagen was used to prepare a medium to screen proteolytic marine bacteria for their ability to elaborate collagenolytic enzymes. The medium was resistant to solubilization by trypsin, hyaluronidase, chondroitinase ABC, and various marine proteinases, but was readily hydrolyzed by commercial Clostridium collagenases. Eighty-seven marine isolates collected in the vicinity of Bermuda, Oahu (Hawaii), and Stone Harbor and Cape May, N. J., were screened. Approximately 44 per cent of the isolates were capable of elaborating enzymes that hydrolyzed reconstituted collagen gels. Several cultures produced collagenolytic enzymes only when grown in the presence of collagen or degradation products of collagen, and with very few exceptions the presence of collagen in the medium greatly enhanced collagenolytic enzyme production. The enzymes from a collagenolytic Bermuda marine isolate were studied in more detail to illustrate that the enzymes capable of hydrolyzing reconstituted collagen were separable from nonspecific proteinases by zone electrophoresis and that these enzymes were true collagenases by virtue of their ability to hydrolyze native bovine Achilles'tendon obtained from three different sources.
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PMID:Collagenolytic activity of some marine bacteria. 16 14

Soluble 125I-labeled type I collagen binds to cultured fibroblasts but not to cultured epithelia. The binding of the ligand to fibroblasts is reversible, saturable and highly specific for sequences contained within the helical portions of the alpha1 and alpha2 chains. The amount of ligand bound is dependent upon cell number and ligand concentration. Binding is decreased but measurable at 4 degrees C. The steady state binding is greater at 26 degrees than at 37 degrees C due to a more rapid dissociation of the ligand-acceptor complex at 37 degrees C. The half-life of the complex is 46 min at 37 degrees C and approximately 2.5 hr at 26 degrees C. Scatchard plots of binding data indicate a single class of high affinity binding sites (KD = 1.2 X 10(-11) M) with each fibroblast binding approximately 500,000 molecules at saturation. Pretreatment of fibroblasts with bacterial collagenase, chondroitinase ABC or testicular hyaluronidase does not affect the binding reaction, whereas pretreatment of the cells with phospholipase C increases the amount of ligand bound. Ligand binding is decreased but not abolished after fibroblasts are treated with trypsin concentrations which remove surface fibronectin. Fibroblast monolayers treated with antiserum against fibronectin bind the radiolabeled ligand normally. In contrast to collagen, addition of excess fibronectin does not accelerate the dissociation of bound ligand from fibroblasts. Possible functions for surface-bound collagen are discussed.
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PMID:Binding of soluble type I collagen molecules to the fibroblast plasma membrane. 45 36

Antibodies to collagen in the synovial fluid of RA patients were determined by radioimmuno assay using 14-C-labeled collagen and by passive hemagglutination with collagen coated erythrocytes. The effect of various glycosaminoglycans, possibly present in synovial fluid, on these two assays was investigated. None of the glycosaminoglycan preparations tested significantly changed either antibody titers or the amount of 14-C-radioactivity precipitated in radioimmunoassay. Digestion of the synovial fluid with chondroitinase ABC likewise had no effect on the results. It is therefore concluded that the glycosaminoglycans present in synovial fluid do not interact with native or denatured collagen under the experimental conditions existing in the determination of antibodies to collagen.
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PMID:Effect of glycosaminoglycans on the detection of antibodies to collagen in synovial fluid. 73 53


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