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V C Duance

Publications and source records attributed to V C Duance.

At least 55 records · Page 3Linked to original sources
PubMed1987

Type I and III collagen content and fibre distribution in normal human skin during ageing.

The content of type I and III collagen in normal human skin from subjects of different ages was studied by means of a new high performance liquid chromatography method and by SDS-polyacrylamide gel electrophoresis and scanning electron microscopy. The ratio of types I and III collagen in covered skin remained constant throughout childhood and young adult life and the proportion of type III was shown to be the same as previously reported. However, in the elderly, the proportion of type III collagen in the dermis increased to a variable degree. Scanning electron microscopic examination showed a decrease in the number of collagen fibre bundles with age. Average bundle width varied significantly with age. These results may reflect an impaired synthesis of type I collagen in aged skin.

Adolescent↗
PubMed1986

Light microscopic immunolocalization of laminin, type IV collagen, nidogen, heparan sulphate proteoglycan and fibronectin in the enteric nervous system of rat and guinea pig.

The localization of the extracellular matrix components laminin, fibronectin and type IV collagen in the enteric nervous system and the surrounding smooth muscle was investigated by immunohistochemical methods, using tissue sections of rat and guinea pig large intestine. None of these molecules were detectable inside the enteric ganglia. In contrast, they were easily demonstrable in association with the basement membrane of satellite cells within sensory and sympathetic ganglia. All of these molecules were, however, present in or nearby the basement membrane that surrounds each enteric ganglion. This agrees with previous ultrastructural observations that, in small mammals, neither basement membranes nor large connective tissue spaces are found inside enteric ganglia. The matrix molecules under study were also detected in the basement membrane of the nearby smooth muscle cells that make up the muscle layer of the gut wall. Fibronectin was frequently observed as a broad staining pattern suggesting its localization in the lamina reticularis rather than in the lamina densa. In addition, nidogen and heparan sulphate proteoglycan were demonstrated in the basement membrane of both enteric ganglia and Schwann cells.

Animals↗
PubMed1986

Distribution and biosynthesis of connective tissue components by synovial fibroblasts cultured with mononuclear inflammatory cells.

Two main cell types, spindle-shaped and large flattened cells, were identified in fibroblast cultures from synovial tissue explants. Type I collagen and fibronectin were visualized by indirect immunofluorescence and the hyaluronic acid coat around the cells by the erythrocyte exclusion method. Collagen was detected as intracellular granules which varied greatly in their number with no correlation to the cell shape. Hyaluronic acid coat was seen only around the spindle-shaped cells, whereas the intercellular fibronectin was found throughout the cultures. Morphological alterations in synovial fibroblasts were detected when subjected to mononuclear cells isolated from peripheral blood. The fibroblast became thinner and branched and stellate cells with numerous extensions appeared. Hyaluronic acid synthetase activity increased by about 50% and was obviously related to the appearance of the stellate cells, whereas no evident change was detected in collagen synthesis. The stellate cells were full of collagen granules. The hyaluronic acid coat around these cells did not differ from that around normal spindle-shaped cells. Synovial fibroblasts cocultured with mononuclear cells lost the intercellular fibronectin network, but other main cell surface glycoproteins studied with the periodate-borohydride method and electrophoresis remained unaltered in spite of morphological alterations.

Arthritis, Rheumatoid↗
PubMed1985

Lipoid proteinosis: an inherited disorder of collagen metabolism?

The dermal collagen of a patient with lipoid proteinosis was investigated by immunohistochemistry and biochemical analysis. The affected skin was found to contain significantly less collagen per unit dry weight than normal dermis but showed elevated levels of type 3 collagen with respect to type I. Purification of collagen types from affected skin after pepsin digestion showed no novel forms, but a doubling in the yield of type 5 collagen. These results correlated well with those of immunohistochemistry which showed a patchy, diffuse, widely distributed type 3 collagen and an increase in types 4 and 5 collagens associated with 'onion skin' endothelial basement membrane thickening. Estimation of collagen cross-links showed an abnormal pattern with a preponderance of the keto-imine form not normally associated with skin. These results strongly suggest that lipoid proteinosis involves a primary perturbation of collagen metabolism.

Adolescent↗
PubMed1985

Collagen and fibronectin in a healing skeletal muscle injury. An immunohistological study of the effects of physical activity on the repair of injured gastrocnemius muscle in the rat.

The presence of the connective tissue components fibronectin and the different types of collagen was demonstrated by histological and immunohistological methods in the granulation and scar tissue of a healing injury in rat muscle. The effects of physical activity on granulation tissue production, scar formation and muscle regeneration at various stages of healing were studied. It was shown that immobilisation after injury accelerates granulation tissue production, but if continued too long, leads to contraction of the scar and to poor structural organisation of the components of regenerating muscle and scar tissue. However, a certain period of immobilisation, about five days for rat muscle, is required to allow newly-formed granulation tissue to cover the injured area and to have sufficient tensile strength to withstand subsequent mobilisation. This mobilisation, at the correct interval, seems essential for the quicker resorption of scar tissue and the better structural organisation of the muscle.

Animals↗
PubMed1984

Isolation and characterization of the precursor of type M collagen.

A 225000-Mr peptide has been purified from rat chondrosarcoma which is immunologically and biochemically related to type M collagen. Rotary shadowing shows this molecule to be twice the length of the type M molecule and has a prominent kink close to one end. We believe this molecule represents parent type M, the form of the molecule in vivo.

Animals↗
PubMed1984

The distribution of types I, III, IV and V collagens in penetrant lesions of the central nervous system of the rat.

The presence and distribution of types I, III, IV and V collagens within open lesions in the rat cerebrum have been demonstrated by immunofluorescent techniques. In the adult animal, types I and III collagens can be identified in the cicatrix from eight days onwards. Types IV and V collagens occur in the basement membrane of the glia limitans formed between the neuropile and the cicatrix and in the basement membranes of the blood vessels. In neonatal animals, less than eight days old at operation and allowed to recover for eight days, no type I or III collagens occur in the lesion and no types IV and V are present along the edge of the neuropile, because a glia limitans is not formed. In animals operated on when eight days old, the adult response is found in the cortex only, but when 16 days old the full adult response occurs in all parts of the lesion.

Animals↗
PubMed1983

Surface of articular cartilage: immunohistological studies.

Using several physical techniques the surface of articular cartilage has been reported to be structurally different from the deeper layers. In this paper using immunohistochemical methods, the surface has been shown to contain a characteristically different collagen, Type I in contrast to Type II which is the major collagen of cartilage. These results support previous proposals for a surface layer, or lamina splendens, the presence of which would be of considerable importance in understanding the degradation of cartilage in arthritides.

Animals↗
PubMed1983

An investigation of the biochemical and histological changes in the collagen of the kidney and skeletal muscle in systemic sclerosis.

Changes in the distribution and quantity of different collagen types in some internal organs was determined in tissues from patients with systemic sclerosis. In addition, sera from patients with systemic sclerosis were assayed for circulating anti-collagen antibodies and were compared with normal sera. The results of a specific immunohistological survey of skeletal muscle and kidney showed a general increase in type I and III collagens in the fibrotic lesions when compared with age matched normal tissue. A thickening of basement membranes was also observed. Biochemical quantitation of the ratio of types I and III collagens in normal and affected kidney showed up to a three-fold increase in type III compared to type I collagen, consistent with the immunohistological data. Finally, quantitation, by the ELISA technique, of circulating anticollagen antibodies in sera from patients with systemic sclerosis demonstrated positive results for types I, III and IV collagens when compared with normal controls. These results are discussed in relation to the clinical progression and possible mechanisms of pathogenesis of the disease.

Adult↗
PubMed1982

Immunofluorescence localization of type-M collagen in articular cartilage.

Normal mammalian articular cartilage has been found to contain several collagenous peptide chains in addition to type-II collagen. We now report the distribution in adult pig cartilage of one of these new peptides, type-M collagen, using type-specific antibodies. Type M is primarily located in the pericellular environment of the cells in the deeper zones of the articular cartilage. The distribution is shown to be distinct from that of type-II collagen. This finding suggests that type-M collagen may play an important role in the metabolism of articular cartilage.

Animals↗
PubMed1982

Collagen types in neuromuscular diseases.

The striking proliferation of connective tissue characteristic of the muscular dystrophies can be attributed predominantly to an increase in endomysial and perimysial type III collagen. Carriers of muscular dystrophy occasionally revealed a slight increase in anti-type III collagen fluorescence, but no abnormalities in collagen disposition were observed in foetuses "at risk" for DMD. In contrast, the proportion of collagen types in neurogenic atrophies appeared normal although anti-type IV and V staining, which delineated the basement membrane, was very intense around atrophied fibres, as was also the case in small fibres in myopathic diseases. The detection of staining with anti-type III, IV and V collagens in splits which are sometimes observed in hypertrophied fibres in the muscular dystrophies supports the suggestion that abnormalities in collagen production, perhaps involving a defective modulation of myoblast-fibroblast expression, may be involved in the pathogenesis of these diseases.

Adolescent↗
PubMed1982

A biochemical and immunohistological study of collagen synthesis in Ewing's tumour.

The synthesis and localization of collagen have been studied on material from a total of 16 primary Ewing's tumours. The predominant collagen extracted from the tissues and synthesized in short-term cultures was type I. The proportion of type III collagen was relatively small and variable (0-8%) in the direct tumour extracts, but a higher proportion (29-38% of the total collagens) was synthesized in culture. Immunofluorescence studies showed that positive staining for all types of collagen tested (types I, III, IV and V) was restricted to stroma; there was no evidence of collagen either within the tumour cells or in their pericellular matrix, a finding endorsed by negative staining for reticulin in the same areas. The absence of any evidence for type IV or V collagen synthesis by Ewing's cells argues against an endothelial origin for the tumour, and indicates that collagen analysis is unlikely to be of value in the diagnosis of this particular sarcoma.

Bone Neoplasms↗
PubMed1981

Identification of two further collagenous fractions from articular cartilage.

Salt fractionation of pepsin-solubilized human and porcine articular cartilage has revealed the presence of two further collagenous fractions, CF1 and CF2, at high salt concentration following the precipitation of Type-II, 1 alpha, 2 alpha, 3 alpha, and Type-M collagens. Both fractions precipitate at 2.0 M NaCl, but higher yields of CF1 are obtained at 3.0 M NaCl. CF1 and CF2 can be separated in the native form using carboxymethyl-cellulose chromatography. Under denaturing conditions, CF1 has an apparent molecular weight of 25 000 and is unaffected by mercaptoethanol, whereas CF2 has a molecular weight of 35 000 before and 12 000 after reduction by mercaptoethanol. These fractions are probably fragments derived from larger collagen molecules, although the cyanogen bromide digest studies suggest that they are derived from a collagenous type other than one of those previously identified in cartilage.

Amino Acids↗
PubMed1980

Amyloid P-component is a constituent of normal human glomerular basement membrane.

Glomerular and other vascular basement membranes were found to contain an antigen that was immunochemically indistinguishable from serum amyloid P-component. There was no immunological cross-reactivity between antisera to serum amyloid P-component and to collagen types I, III, IV, or V. The amyloid P-component antigen was confined to the endothelial aspect, the lamina rara interna, of glomerular basement membrane. It could not be eluted by high-ionic-strength saline, EDTA, dithiothreitol, or either polar or nonpolar detergents, but was released into solution when isolated glomerular basement membrane was digested by highly purified bacterial collagenase. Most of these P-component molecules and their constituent polypeptide chains were of higher molecular weight and lower isoelectric point than serum amyloid P-component. These findings indicate that, as well as being a normal plasma protein and a universal constituent of amyloid deposits, P-component is also a normal matrix glycoprotein of basement membrane in which it is covalently linked to collagen and/or other matrix proteins. This may be relevant both to the pathogenesis of amyloidosis and to other aspects of physiology and pathology of basement membranes.

Amyloid↗
PubMed1980

The distribution of collagen types I, III and V (AB) in normal and atherosclerotic human aorta.

Collagen of types I, III and V has been identified and localised in adult human aorta, coronary arteries and atherosclerotic plaques using an indirect immunofluorescent method with specific antibodies to human collagen antigens. The distribution of the three types of collagen was distinct. Type I collagen was found around smooth muscle cells in the aortic media and in large amounts in the atherosclerotic plaque. Type III collagen was found in dense deposits alongside the elastic laminae in the aortic media and in diffuse intimal thickening. In the aortic media, there appeared to be more type III collagen than type I. The reverse was true in advanced atherosclerotic plaques. Type V collagen was distributed throughout the extracellular matrix in the aortic media and in the subendothelial region of plaques. These findings confirm earlier biochemical studies and suggest that a major shift in the nature of collagen synthesis occurs within advanced atherosclerotic plaques.

Aged↗