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A Kadouri

Publications and source records attributed to A Kadouri.

27 records · Page 2Linked to original sources
PubMed1990

Phosphatidylinositol liposomes increase calcium uptake and tissue plasminogen activator secretion by fetal human lung fibroblasts.

PtdIns liposomes, at a concentration of 40 microM, induced in FLF the synthesis of t-PA-Ag, and enhanced 45Ca2+ uptake. The induction of t-PA-Ag biosynthesis by PtdIns liposomes in FLF was inhibited by 5-15 microM verapamil, an inhibitor of Ca2+ uptake via the so-called "slow channels" by 0.5-10 microM TFP, an inhibitor of Ca2+ transport ATPase, and by 10-90 microM TMB-8, an inhibitor of intracellular Ca2+ mobilization. t-PA-Ag secretion was inhibited by decreasing the Ca2+ concentration less than 1.2 mM. On the other hand, addition of 0.08 microM of calcium ionophore A23187 increased t-PA-Ag biosynthesis after 72 hr of incubation by 247% (P less than 0.01). These data support previous results and indicate that the synthesis of t-PA in FLF is Ca2+ dependent. Thus, it is suggested that PtdIns liposomes increase t-PA biosynthesis by affecting calcium metabolism.

Calcimycin↗
PubMed1990

Tissue plasminogen activator levels in different types of polycythemia.

The plasma level of tissue plasminogen activator antigen (t-PA-Ag) was examined in 86 patients with polycythemia (29 polycythemia vera, 11 secondary polycythemia and 46 with spurious polycythemia) and 24 healthy volunteers. Tissue plasminogen activator antigen was significantly decreased in patients with polycythemia vera in comparison with healthy controls. On the other hand, in patients with spurious polycythemia and secondary polycythemia t-PA-Ag concentration was significantly increased. There was no significant difference in t-PA-Ag levels in polycythemic patients with or without thromboembolic disease. A significant correlation was detected between t-PA-Ag level and hemoglobin or hematocrit concentration in patients with polycythemia vera (p = 0.02, r = 0.43). However, in patients with secondary polycythemia and spurious polycythemia, no significant correlation between t-PA-Ag and hemoglobin level was found. Plasminogen activator inhibitor (PAI) levels in patients with polycythemia vera and healthy volunteers did not differ significantly.

Aged↗
PubMed1988

Adaptation of culture methods for NMR studies of anchorage-dependent cells.

Two methods for growing anchorage-dependent cells were adapted for nuclear magnetic resonance (NMR) measurements: growing cells on agarose polyacrolein microsphere beads and on "filters" made of nonwoven polyester fabric. Both were found to be convenient and most suitable for NMR studies in any conventional spectrometer without probe modification. These methods were employed in studies of human breast cancer T47D-A11 cells, using scanning electron microscopy and 31P NMR spectroscopy. The results show that the contents per cell of phosphorylcholine, phosphorylethanolamine, and their glycerol derivatives depend on the mode of cell assembly and decrease gradually with the increase in cell-cell interaction along the growth curve.

Cell Adhesion↗
PubMed1985

Factors affecting the production of plasminogen activator in cultures of normal fibroblasts.

Plasminogen activator (PA) is a serine protease with a proven medical application as a fibrinolytic drug. PA is a normal constituent of animal tissues and is found in low concentration 1-10 U/ml in the supernatant of various cells in culture. We found that certain strains of untransformed human diploid fibroblasts can be adapted to produce PA at levels of 100 U/ml or more by culture with specific combinations of serum and coated substrates. Once the cells are adapted, they continue to produce the enzyme in a medium devoid of serum in which cell proliferation is minimal. The time course of enzyme production revealed that its formation is controlled by negative feedback and stops when its level in the medium reaches a critical concentration. However on removal of the enzyme by continuously replacing the medium, the cells continue to produce enzyme at a constant rate for a period of several weeks. Possible biotechnological configurations for large scale production of this enzyme are now under study. The PA purified from the spent medium of these cells was identified as tissue type activator similar to the melanoma type PA.

Cells, Cultured↗
PubMed1975

Satellite-rich DNA in cucumber: hormonal enhancement of synthesis and subcellular identification.

Cucumber hypocotyl DNA in neutral CsCl distributes into a mainband comprising 59% of the total, and two large satellite bands which contribute 41% to the DNA pattern. Organelle enrichment studies show that the densities of mitochondrial and chloroplast DNA coincide with those of the satellite bands. At least 12-19% of total cucumber DNA is associated with the cytoplasmic organelles. These values, which are several times larger than those usually quoted for higher plants, are correlated with an unusually low amount of DNA per haploid nucleus in cucumber. Synthesis of the satellite DNAs, as well as mainband DNA, is appreciably stimulated in vivo by application of the plant hormone, gibberellin. Endogenous and hormone-enhanced synthesis of the satellite DNAs is proportionately greater in target tissue showing a high rate of organelle synthetic activity.

Journal Article↗