PubMed Health⌕ Search

Biomedical subjects

E C Leroy

Publications and source records attributed to E C Leroy.

16 recordsLinked to original sources
PubMed1992

Growth and characterization of fibroblasts obtained from bronchoalveolar lavage of patients with scleroderma.

We describe the detection and the growth of fibroblasts with human smooth muscle cell differentiation features from bronchoalveolar lavage (BAL) fluid of 53% of patients with scleroderma, but not from healthy controls. The binding of alpha-actin, vimentin and desmin antibodies by scleroderma lung fibroblasts exceeded that of normal adult lung fibroblasts, indicating that scleroderma lung fibroblasts express some markers of human smooth muscle cell differentiation (myofibroblasts), which may account for differences in biological behavior. A mesenchymal cell phenotype was documented by mRNA analysis, showing high expression of collagen type I and fibronectin in these cells. Fibronectin is also released in significantly higher amounts by scleroderma alveolar macrophages than by macrophages from healthy donors.

Actins↗
PubMed1991

Fibronectin release by systemic sclerosis and normal dermal fibroblasts in response to TGF-beta.

To determine whether enhanced matrix synthesis by systemic sclerosis (SSc) fibroblasts in vitro is due to increased responsiveness to transforming growth factor-beta (TGF-beta), fibronectin release by SSc and normal fibroblasts (7 pairs) was measured at various concentrations of TGF-beta. In the absence of TGF-beta, SSc fibroblasts released 30 +/- 22% more fibronectin than normal fibroblasts. While both SSc and normal fibroblasts increased fibronectin release at all concentrations of TGF-beta tested, the percentage increases were not statistically greater for the SSc fibroblasts even though 4 of the SSc fibroblasts strains were selectively sensitive to low concentrations of TGF-beta. TGF-beta increased cell numbers of both SSc and normal strains equally. Our data confirm abnormal regulation of fibronectin gene expression in SSc fibroblasts and suggest increased sensitivity to TGF-beta by some SSc fibroblast strains.

Blotting, Western↗
PubMed1987

Ascorbate effects on type I procollagen synthesis by human adult skin fibroblasts: different migration positions of type I procollagen chains on SDS polyacrylamide gel after incubation with ascorbate.

The effects of ascorbate and steroids on type I procollagen synthesis by human skin fibroblasts were studied. Ascorbate treatment (50 micrograms/ml) for 24 hours stimulated a 2-3 fold increase in type I procollagen synthesis and an unexpected shift in the mobility of type I procollagen on SDS polyacrylamide gels. The kinetics of the increase in procollagen synthesis (4 hours) and the shift in electrophoretic mobility (1 hour) were dissimilar, suggesting different controlling mechanisms. This was confirmed by the addition of alpha-alpha'-dipyridyl to ascorbate-treated cultures which eliminated the ascorbate-induced shift in electrophoretic mobility without altering the amount of procollagen synthesis. In contrast, hydrocortisone (1.5 microM) reduced the ascorbate-induced stimulation of type I procollagen synthesis by 80% but did not affect the ascorbate-induced shift in electrophoretic mobility. These studies indicate that the ascorbate-induced increase in type I procollagen synthesis is due to increased levels of type I procollagen mRNA and is independent of the level of hydroxylation of the procollagen.

2,2'-Dipyridyl↗
PubMed1979

DNA binding activity of serum from patients with systemic lupus erythematosus.

The reaction conditions essential for reproducible use of the cellulose ester membrane filter assay for anti-DNA antibody levels in patients with systemic lupus erythematosus are described. A dependence of DNA-binding capacity on serum concentration was observed in the assay, requiring that serum concentrations be comparable in determinations of DNA-binding activity of different sera and when comparing different published studies. The DNA-binding capacity of serum from lupus patients was found to be significantly different from that of healthy controls. However, the binding capacities were not significantly different between lupus patients with and without nephritis. The relative avidity of the anti-DNA antibodies were estimated from plots of 1/DNA bound vs 1/DNA free and these data indicate that the avidities of the antibodies from the two groups of lupus patients are not significantly different. This observation suggests that the tightness of binding between the DNA and the serum anti-DNA antibodies cannot be used to predict immune complex-induced nephritis in lupus patients.

Antibodies↗
PubMed1978

In vivo observations of skin capillaries in workers exposed to vinyl chloride. An English-American comparison.

An unselected sample of vinyl chloride (VC)-exposed individuals, all employees of a polyvinyl chloride production plant in England (129 subjects), were examined by in vivo capillary microscopy. Results were compared with those previously obtained from a similar study in the USA to determine whether an association between VC exposure and capillary abnormalities could be found in different environments. The results showed a similar distribution of capillary abnormalities among the VC workers in both countries (39.5% in England compared with 36% in the USA). These capillary abnormalities were significantly more frequent among VC-exposed subjects than among control industrial workers (7.7%, 6%). In vivo microscopy also showed a higher incidence of papular lesions (13.5%) than had been detected clinically (1%).

Adolescent↗
PubMed1975

Blood viscosity, plasma proteins, and Raynaud syndrome.

The rheology of the blood was studied in 20 patients with Raynaud syndrome. Sixteen patients had scleroderma, two had nonspecific angiitis, one had systemic lupus erythematosus, and one had Raynaud disease. Viscosity measurements were performed on whole blood, plasma, and suspensions of 45% red blood cells (RBCs). In autologous plasma, over a wide range of shear rates. The relative viscosity, an index of RBC aggregation, was obtained by dividing the RBC viscosity in autologous plasma (at a hematocrit value of 45%) by the plasma viscosity. Concentrations of the plasma globulins and fibrinogen were also measured. The mean plasma viscosity was significantly (P less than .01) elevated over established normal controls. The mean RBC viscosity and the relative viscosity were significantly (P less than .01) elevated over normal controls, as were fibrinogen and the globulins. These studies demonstrate increased blood viscosity and red blood cell aggregation, which may constitute an important hindrance to flow.

Adolescent↗
PubMed1972

Connective tissue synthesis by scleroderma skin fibroblasts in cell culture.

Skin fibroblasts from subjects with scleroderma and control subjects were grown in tissue culture to compare the characteristics of connective tissue metabolism. A striking increase in soluble collagen (media hydroxyproline) was observed in eight of nine scleroderma cultures when they were compared with identically handled control cultures matched for the age and sex of the donor and the anatomic site of the donor skin. Glycoprotein content as estimated by hexosamine and sialic acid was also significantly increased in the scleroderma cultures. Estimations of protein-polysaccharide content by uronic acid determinations were low in all cultures and not significantly increased in scleroderma cultures. This report demonstrates the feasibility of using fibroblast cell cultures to study chronic rheumatic and connective tissue disorders. The initial results suggest a net increase in collagen and glycoprotein synthesis in scleroderma fibroblast cultures. The implications of an abnormality of connective tissue metabolism by skin fibroblasts propagated in vitro in the acquired disorder scleroderma are discussed.

Cell Count↗