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F Dupuit

Publications and source records attributed to F Dupuit.

7 recordsLinked to original sources

Modulations of the epithelial phenotype and functional activity of cultured bovine tracheal gland cells: dependence on the culture medium and passage number.

Bovine tracheal gland (BTG) cells in culture show an epithelial-fibroblastoid transition after several passages. To investigate these BTG cell phenotype changes, we studied the effects of both the culture medium and passage number on the expression of epithelial cytoskeletal proteins and glandular serous cell markers. We also analyzed the intracellular cAMP level in the basal state and after adrenergic stimulation. Three culture media were used: 1) serum-free defined medium (SFDM); 2) medium supplemented with 2% Ultroser G; and 3) medium supplemented with 10% fetal calf serum (FCS). Using immunofluorescence microscopy, we showed that, in the first 4 passages whatever the culture conditions, BTG cells expressed immunoreactivities to cytokeratin filaments and desmoplakins I and II, whereas vimentin filaments were not detected. After four passages, BTG cells cultured in 10% FCS or 2% Ultroser G became progressively fibroblastoid and showed immunoreactivities to both vimentin and cytokeratin intermediate filaments. No immunoreactivity to vimentin filaments was observed on BTG cells cultured in a SFDM. Using biochemical analysis, we showed that basal levels of cAMP in cultured BTG cells and lysozyme secretion by these cells vary according to the culture medium and passage number. It was higher in BTG cells cultured in a SFDM compared to that recovered from cells cultured in medium supplemented with Ultroser G or FCS. Whatever the culture medium, BTG cells responded to stimulation by isoproterenol. However, the results of stimulation in a SFDM were higher than in Ultroser G or FCS supplemented medium. We conclude that the BTG epithelial cell organization and the regulation of biosynthesis of secretory proteins by these cells in culture depend on both the culture medium and passage number.(ABSTRACT TRUNCATED AT 250 WORDS)

1-Methyl-3-isobutylxanthine

Production of lipocortin-like proteins by cultured human tracheal submucosal gland cells.

Evidence is obtained for the presence of lipocortin-like proteins in human tracheal gland cells in culture. Using polyclonal antibodies to lipocortin I, indirect immunofluorescence studies demonstrate that lipocortin I is mainly confined to the tracheal gland cell surface. From cell membranes, four Ca2(+)-dependent proteins (35, 40, 45 and 67 kDa) were identified as lipocortin related proteins by using immunoblotting and fluorography following [35S]methionine metabolic labeling experiments. A strong immunoreactivity for the 35 kDa protein was observed. In addition, lipocortin-like proteins with apparent Mr33, 35, 37 and 67 kDa, respectively, were released in the apical culture medium by tracheal gland cells cultured on microporous membrane of a double chamber culture system.

Annexins

Modulation of albumin-like protein and lysozyme production by bovine tracheal gland serous cells. Dependence on culture conditions.

Bovine tracheal submucosal gland serous cells were cultured in medium supplemented with either 10% fetal calf serum or 2% Ultroser G, a commercial serum substitute for cell culture. The proteins synthesized and secreted into the culture medium during [35S]methionine pulse, chase and isoproterenol-stimulated periods were analyzed. Marked differences in the patterns of secretory radiolabeled proteins with Mr values ranging from 15,000 to 95,000 were observed between pulse and chase media of cells cultured in fetal calf serum and Ultroser G. In the presence of Ultroser G, albumin-like protein production was inhibited 95% as compared to cultures incubated with fetal calf serum. A bovine lysozyme-type enzymatic activity was detected only in medium from stimulated cells cultured in Ultroser G. The results suggest that bovine tracheal serous cells synthesize different proteins according to the composition of culture medium and release certain proteins when adrenergically stimulated.

Albumins

[Annulo-aortic ectasia].

On the basis of a literature review and the study of 18 cases, the authors examine annuloaortic ectasia, which involves dilatation of the fibrous ring of the heart at the aortic orifice, marked by aortic regurgitation and dystrophic aneurysm of the ascending aorta. The authors noted a predominantly muscular disorder (14 males, 4 females) often detected from an assessment of aortic regurgitation without clinical, radiologic or specific electrical features. The value of echocardiography and Doppler echocardiography is clearly apparent from the diagnosis of the disease, monitoring of progress, selection of patients for invasive pre-operative explorations and post-operative surveillance. The developing gravity of this disease is stressed, rapid repercussions in the left ventricle intervening more than complications due to ectasia itself. This indicates the urgency of complete replacement of the whole ascending aorta and of the aortic valve with reimplantation of coronary arteries as in the Bentall or Bentall-Cabrol surgical intervention, seven cases of which have been reported with satisfactory results.

Adult

Growth and characterization of isolated bovine tracheal gland cells in culture. Influence of a reconstituted basement membrane matrix.

We describe a method for establishing the culture of bovine tracheal submucosal gland (BTG) cells, in which we have also examined the influence of a reconstituted basement membrane matrix derived from the Engelbreth-Holm-Swarm tumor (EHS) on the growth and morphological differentiation of these cells. BTG cells have been isolated by tissue enzymatic digestion using trypsin, deoxyribonuclease I, elastase, hyaluronidase and EGTA for 1 hr at 37 degrees C. Afterwards, cells and tissue were collected by centrifugation and were incubated for 15 min with 15% newborn calf serum to inactivate the proteolytic enzymes. Enzymatic digestion using only trypsin, centrifugation and inactivation steps were repeated three times. Using this protocol, we obtained 15 +/- 4 (X 10(6] cells per g of tracheal submucosa with 72 +/- 2% (n = 5) cell viability. On microscopic observation, isolated cells were mainly composed of serous type glandular cells. Cells were cultured in a 1:1 medium of Dulbecco's Modified Eagle's/Ham's F12 supplemented with 10% fetal calf serum and subcultured in either plastic flasks or flasks coated with EHS matrix. On the plastic, the BTG cells exhibited at confluency an epithelioid appearance. They stained positively with the immunofluorescent anticytokeratin antibody and contained PAS-staining granules. By electron microscopy, lactoferrin, a protein marker specific to the serous cells, was demonstrated immunocytochemically in small secretory vesicles. BTG cells cultured on EHS matrix revealed a significantly increased growth in comparison to those cultured on plastic. In post-confluent culture of BTG cells on EHS matrix, we observed numerous dome-like structures formed by differentiated cells which were joined together around luminal spaces.

Animals

[Structure and secretory functions of the respiratory epithelium].

Airway secretions actively participate in respiratory epithelium protection. Apart from its main participation in transport of inhaled microorganisms and particles by mucociliary clearance, respiratory mucus also contributes to other protective purposes such as the control of airway humidification. Biochemical components found in secretions, such as mucins, lipids, antibacterial agents (secretory IgA, lysozyme, lactoferrin), antioxidant and antiprotease components, contribute significantly to the airway epithelium defense.

Cells, Cultured