PubMed Health⌕ Search

Biomedical subjects

R Penttinen

Publications and source records attributed to R Penttinen.

At least 37 records · Page 2Linked to original sources
PubMed1986

Lysyl oxidase activity and synthesis of desmosines in cultured human aortic cells and skin fibroblasts: comparison of cell lines from control subjects and patients with the Marfan syndrome or other annulo-aortic ectasia.

The activity of lysyl oxidase, the cross-linking enzyme of elastin and collagen, was measured in culture media of human skin fibroblasts, human aortic medial smooth muscle cells (SMCs) and adventitial fibroblasts using [3H]lysine-labelled elastin substrate. In addition, biosynthesis of isodesmosine and desmosine, the cross-linking amino acids of elastin, was studied by metabolic labelling with [14C]lysine and subsequent amino acid chromatography of protein hydrolysates. Lysyl oxidase activity in culture media of skin fibroblasts and aortic smooth muscle cells increased with the growth of the cell population and was at the highest level in cultures of high cell density. Lysyl oxidase activity in the aortic cell cultures was about three times that of skin fibroblasts. Aortic smooth muscle cells synthesized at least 100 times more desmosines than skin or adventitial fibroblasts. No differences were observed in lysyl oxidase activity and synthesis of desmosines between aortic smooth muscle cells or skin fibroblasts from patients with the Marfan syndrome or other annulo-aortic ectasia (dilatation of the ascending aorta) and the corresponding controls.

Adolescent↗
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

The borohydride-reducible compounds of human aortic elastin. Demonstration of a new cyclic amino acid in alkali hydrolysate, and changes with age and in patients with annulo-aortic ectasia including one with Marfan syndrome.

Human aortic elastin reduced with [3H]borohydride was analysed by ion-exchange chromatography after alkali or acid hydrolysis. Alkali hydrolysates of elastins contained a radioactive peak that was eluted between proline and leucine. This peak was not present in foetal elastin, but its proportion increased steadily during aging. Aortic samples from patients with annulo-aortic ectasia (aneurysm of the ascending aorta), including one with classical Marfan syndrome, contained less elastin (CNBr-insoluble material) than did the age-matched controls. The proportion of radioactivity in the new peak of all these aortas was low when compared with age-matched controls. Gas-chromatographic/mass-spectrometric analysis suggested that it contained a cyclic derivative of a hydrated aldol-condensation product. The concentration of the cross-link precursors, lysine aldehyde and aldol-condensation product (estimated from the acid-hydrolysis product 6-chloronorleucine and the acid-degradation product of reduced aldol-condensation product) was high in very young aortas but remained quite stable after childhood. No differences were observed in cross-link profiles of acid hydrolysates between pathological and control aortas. A low proportion of radioactivity in the new peak may indicate the presence of young or immature elastin in the pathological aortas.

Adult↗
PubMed1985

Changes in intramuscular collagen and fibronectin in denervation atrophy.

The distribution of collagen types I, III, and V and fibronectin was investigated by means of immunofluorescent techniques in denervated and normal rat skeletal muscle. During a period of 28 days, a distinct atrophy developed in the denervated gastrocnemius muscle and was accompanied by an increase in types I and III collagen in the endomysium and perimysium. The amount of type V collagen showed little change, whereas fibronectin increase closely parallelled types I and III collagen. The results indicate that denervation atrophy in muscles is accompanied by striking fibrotic changes due to mesenchymal types I and III collagen.

Animals↗
PubMed1985

Synthesis of glycosaminoglycans and collagen in skin fibroblasts cultured from a patient with lichen myxedematosus.

A patient is described with typical skin lesions of lichen myxedematosus and IgG-type lambda paraproteinemia. Fibroblasts cultured from the skin of the patient and from the skin of control persons were used to study glycosaminoglycan and collagen synthesis; the cultures were labelled with 3H-glucosamine and 3H-proline, respectively. Fibroblasts from the patient grew to a cell density which was lower than that of the control fibroblasts. The production of glycosaminoglycans was increased in lichen myxedematosus cultures, so that the ratio of hyaluronic acid to sulphated glucosaminoglycans was higher in the patient's cultures than in control cultures. Collagen production in the patient's cultures was about half of that in control cultures, whereas the ratio of type III to type I collagen was normal.

Cells, Cultured↗
PubMed1985

Disturbed metabolism of copper and zinc in aspartylglycosaminuria: possible involvement with connective tissue changes.

In aspartylglycosaminuria (AGU), a lysosomal storage disorder of glycoprotein degradation, there are some abnormalities in collagen and proteoglycan metabolism. Because of earlier observations suggesting a disturbance of copper balance, the metabolism of copper and zinc was studied in more detail to find out if possible trace metal disturbances could be correlated with connective tissue disorder. Highly elevated copper concentrations in the hair and significantly reduced zinc levels in serum and urine were detected in AGU patients indicating a disturbance of trace element balance. However, the patients had normal serum copper levels, and the concentrations of zinc and copper in cultured fibroblasts did not differ from those of control cells. Normal lysyl oxidase activities in cell culture indicate that collagen cross-link formation is not affected. The changes in copper and zinc balance are probably secondary to the basic enzyme deficiency, and may contribute to the development of the clinical signs and symptoms of AGU although the mechanisms involved are not yet understood.

Acetylglucosamine↗
PubMed1985

Elastin and collagen in the aortic wall: changes in the Marfan syndrome and annuloaortic ectasia.

Elastin and collagen concentrations were determined in intimal-medial samples of ascending aortas from healthy controls of different ages and from 20 patients with annuloaortic ectasia (AAE). Five patients had the Marfan syndrome. In controls the highest elastin concentrations (estimated from desmosine concentrations or insoluble residues after hot-alkali extraction) were found in children. During aging until 60 years, elastin concentration decreased when determined by the hot-alkali extraction method while desmosine concentration changed less. Aorta samples from the Marfan-syndrome patients showed a great variation of elastin concentration from total lack to normal values. Samples from the other AAE patients could be divided into two groups. One contained clearly less elastin and more collagen than the controls whereas in the other group this difference was less marked. Histological examination of the aortic wall of the first group also showed marked fibrosis accompanied by severe elastin fragmentation and acellularity. From the 15 non-Marfan patients 14 were men. By means of clinical examination these patients could also be divided into "familial" and "nonfamilial" groups, because increased diameter of the aortic root was found in relatives of almost half of the patients. However, there were no differences in elastin and collagen concentrations between the familial and nonfamilial cases. As well, no correlation was found between biochemical findings and diameters of the aortic roots. These results point to altered elastin and/or collagen metabolism in the aortic wall of AAE patients.

Adolescent↗
PubMed1984

Electrostimulation of rat callus cells and human lymphocytes in vitro.

Asymmetrical pulsing low voltage current was supplied via electrodes to cultured rat fracture callus cells and human peripheral blood lymphocytes. The [3H]thymidine incorporation of the callus cells and 5-[125I]iodo-2'-deoxyuridine incorporation of the lymphocytes were determined. The growth pattern of callus cells (estimated by cellular density) did not respond to electrical stimulation. However, the uptake of [3H]thymidine was increased at the early phase of cell proliferation and inhibited at later phases of proliferation. The [3H]thymidine uptake of confluent callus cell cultures did not respond to electrical stimulation. Lymphocytes reacted in a similar way; stimulated cells took up more DNA precursor than control cells at the early phase of stimulation. During cell division, induced by the mitogens phytohemagglutinin and Concanavalin-A, the uptake of DNA precursor by stimulated cells was constantly inhibited. The results suggest that electrical stimuli affect the uptake mechanisms of cell membranes. The duality of the effect seems to be dependent on the cell cycle.

Animals↗
PubMed1984

Neurofibromatosis tumor and skin cells in culture. II. Structural proteins with special reference to the cytoskeletal and cell surface components.

Structural proteins of cultured neurofibromatosis (NF) tumor and skin cells were studied with reference to control skin fibroblasts. In polyacrylamide gel electrophoresis (PAGE)/fluorography the banding patterns of the cell lysates were markedly similar. NF tumor cells, however, produced a 60 kD band with a stronger and a 48 kD band with a lighter protein staining and metabolic labeling intensity. Furthermore, skin cells were also characterized by a 26 kD protein and the tumor cells by a 22 kD protein with high metabolic labeling intensity. Neuraminidase/galactose oxidase/NaB3H4-labeled NF skin and control skin cells possessed a 220 kD protein that was less intensively labeled in the tumor cells. The banding pattern of the skin cells was also characterized by a protein with slightly lower molecular weight (86 kD) than that of the tumor cell lysates (90 kD). In all cell lines studied indirect immunofluorescence stainings revealed bright arrays of vimentin type intermediary filaments but no desmin, cytokeratin, glial fibrillary acidic protein (GFAP), or neurofilament proteins. NF skin and control skin cells possessed well developed actin-containing bundles of microfilaments, while those of the tumor cells lacked a typical stress-fiber organization. The general morphology of the tumor cell cultures was also irregular. Transmission electron microscopy revealed no basic differences in the structure of intermediary filaments or microfilaments. The present data provide basic knowledge of neurofibromatosis skin and tumor cells and demonstrate that cultured cells originating from neurofibromas are defective in both their intracellular and extracellular organization.

Actins↗
PubMed1984

Metabolism of collagen in aspartylglycosaminuria: urinary excretion of hydroxyproline.

Aspartylglycosaminuria (AGU) is a lysosomal storage disorder of glycoprotein degradation characterized by severe mental retardation and connective tissue alterations. We have previously described low collagen production in skin fibroblast cultures from AGU patients. In the present work we showed that the urinary excretion of hydroxyproline (total, non-dialysable and free hydroxyproline as indicators of collagen metabolism) was reduced in young AGU patients in comparison with age-matched controls. In adult patients no significant difference was detected. The results support the view that reduced collagen production is associated with the connective tissue abnormalities in this disorder.

Acetylglucosamine↗
PubMed1984

Distribution of different collagen types and fibronectin in neurofibromatosis tumours.

Collagen types I, III, IV and V and fibronectin were localized in neurofibromas from six patients with von Recklinghausen's neurofibromatosis (NF) using indirect immunofluorescence (IIF) and peroxidase anti-peroxidase (PAP) techniques. Type I and III collagens were abundantly and rather evenly present in the tumours and formed a continuous network, but were absent from the capillary endothelial walls and were sparse in the perineurium of the occasional nerve fascicles. The type III/type I + type III collagen ratio in neurofibromas varied from 17.4% to 37.3% when estimated with cyanogen bromide peptide analysis. Fibronectin was detected in areas where type I and III collagens were present but was most intensively stained in the vascular walls and perineurium. Type IV collagen was detected at the dermo-epidermal junction of the skin overlying the tumours, in the endothelial cells of the capillaries, the perineurium and endoneurium. Furthermore, in the tumourous stroma there was plenty of type IV collagen appearing as a discontinuous patchy pattern suggesting abundant basement membrane material associated with cells forming the tumours. Type V collagen distribution was very similar to that of type IV collagen.

Collagen↗
PubMed1984

Xanthoma tendinosum in a normolipemic ectodermal dysplasia patient.

A female patient with congenital ectodermal dysplasia is described, who developed xanthoma tendinosum in her hands simulating rheumatoid arthritis. The serum lipids of this patient were normal. Both ectodermal dysplasia and xanthoma tendinosum in a normolipemic patient are rather uncommon and to our knowledge have not been previously reported in one and the same patient.

Adult↗
PubMed1984

Characterization of plasma membranes and rough endoplasmic reticulum of synovial cells cultured from rheumatoid arthritis patients.

[35S]methionine-labelled plasma membrane (PM) and rough endoplasmic reticulum (RER) proteins were analysed from synovial cell cultures derived from rheumatoid arthritis (RA) and reference patients. Pure RER was prepared by a modification of CsCl-containing sucrose-cushion method. The PM proteins were resolved into 30-35 bands using sodium dodecyl sulphate-electrophoresis in polyacrylamide gradient gels. The major polypeptides had apparent molecular masses of 170, 140, 110, 60, 40, 33, 23 and 14 kilodaltons. The major RER polypeptides had the apparent molecular masses of 170, 74, 58 and 35 kD. No reproducible differences were demonstrated in the polypeptide patterns or in the specific activities of the PM and ER (endoplasmic reticulum) marker enzymes between cells from RA and reference patients. The results reflect similarities of membrane structures in RA and reference cells, although differences have been reported in their metabolism.

Arthritis, Rheumatoid↗
PubMed1984

Abnormal collagen fibrils in aspartylglycosaminuria. Altered dermal ultrastructure in a glycoprotein storage disorder.

Patients with aspartylglycosaminuria, a lysosomal storage disorder of glycoprotein degradation, express connective tissue signs that refer to impaired mechanical properties of the tissue. We studied the ultrastructure of the dermis of patients with aspartylglycosaminuria to detect possible alterations in the connective tissue matrix, alterations that could explain the clinical findings. The organization of fiber bundles was studied by light microscopy and scanning electron microscopy, and diameters and volume densities of individual collagen fibrils were measured. The histologic organization of the dermis in patients with aspartylglycosaminuria was normal. However, by scanning electron microscopy a looser organization and more irregular orientation of the fiber bundles were detected. Transmission electron microscopy revealed a strikingly abnormal variation in the diameters of individual collagen fibrils (from 20 to 160 nm) in all layers of the dermis, with slight irregularity of shape especially in the thickest fibrils. Occasional giant fibrils (greater than 200 nm) were observed. The distribution of the ruthenium red-positive material around the fibrils was normal. Ultrastructural changes similar to these have been found in the collagen fibrils of some patients with Ehlers-Danlos syndrome as well as certain other disorders affecting dermal connective tissue. Altered collagen fibril formation offers an explanation for the connective tissue lesions in aspartylglycosaminuria.

Acetylglucosamine↗
PubMed1983

Neurofibromatosis tumor and skin cells in culture.

Skin fibroblasts and tumor cells were cultured from four patients with peripheral von Recklinghausen's neurofibromatosis (NF). The cell type enriched in culture from the tumors carried the fibroblastic Thy 1.1. cell surface antigen and produced fibronectin, like fibroblasts from skin of NF-patients or from control persons. In electron micrographs the NF tumor and NF skin cells were similar to the control skin fibroblasts; elongated in shape, contained tubular mitochondria, variable amounts of granular endoplasmic reticulum, numerous lysosomal inclusion bodies and collections of 5 nm filaments. Trypsinized cells were fractionated with centrifugation in a Percoll density gradient. All cell lines produced only one sharp band of viable cells at the buoyant density of 1.03. Compared with the NF skin or control skin fibroblasts the NF tumor cells, however, produced a less well organized peri- and extracellular matrix estimated from fibronectin fluorescence. The nuclear sizes were measured from photographs of the cultures. The nuclei of all four tumor cell lines were larger than those of the skin fibroblasts of the corresponding patients. Neurofibromatosis tumor cells thus resemble skin fibroblasts in their density and in some ultrastructural properties but are different in their growth pattern and synthetic functions.

Adult↗
PubMed1983

Effect of Mycoplasma pulmonis infection on protein and glycosaminoglycan synthesis of cultured connective tissue cells.

Human synovial cells, fetal skin fibroblasts and rat granulation tissue fibroblasts were experimentally infected with Mycoplasma pulmonis, a species identified as a contamination of cell cultures, and studied for collagen, total protein and glycosaminoglycan synthesis. Hyaluronic acid and sulfated glycosaminoglycan synthesis were stimulated in cultures where the infection reduced cell density, while they were retarded in cultures which had proliferated into higher density than the controls. An extra polypeptide with molecular weight of 20 kD was seen in [35S]methionine-labelled cells. Media of rat granulation tissue cells showed a shift of a 39-42 kD polypeptide to 33-36 kD position in [35S]methionine and [3H]proline labellings. Other minor changes were also noticed. Collagen synthesis or procollagen conversion to collagen were, however, not altered.

Animals↗
PubMed1983

Lentil lectin-bound glycoproteins of cultured rheumatoid synovial cells.

Synovial cell lines were cultured from 5 rheumatoid arthritis (RA) patients, from 4 patients with other synovial inflammation and from 4 non-inflammatory controls. Protein synthesis was studied by [35S]methionine labelling. Glycoproteins containing D-glucose or D-mannose were separated by affinity chromatography with immobilized lentil lectin and analysed by SDS-electrophoresis in polyacrylamide gradient gels (SDS-gradient PAGE). About 12% of labelled protein was bound to the lectin column (range 7.9-20.0%). Proteins of RA cells showed no differences in binding compared with proteins of the reference cells. At least 40 glycoproteins were separated by SDS-gradient PAGE. No new or missing bands were observed in RA cells, but several quantitative changes and microheterogeneity of some polypeptide molecular weights were noted.

Adult↗