In patients suffering from chronic renal insufficiency (CRI) serotonin (5HT) metabolism is impaired, and plasma 5-hydroxyindoleacetic acid (5HIAA) levels (main metabolite of 5HT) are increased. In this study we aimed to give a detailed... more
In patients suffering from chronic renal insufficiency (CRI) serotonin (5HT) metabolism is impaired, and plasma 5-hydroxyindoleacetic acid (5HIAA) levels (main metabolite of 5HT) are increased. In this study we aimed to give a detailed description of peripheral serotonin metabolism in healthy subjects and patients with CRI, and to evaluate the efficacy of hemodialysis in the elimination of cumulated 5HT and 5HIAA. 5HT (platelet rich plasma, platelet poor plasma, urine, HPLC with electrochemical detection) and 5HIAA (plasma, urine, HPCL with electrochemical detection) levels were evaluated in 14 conservatively treated (CT) and 12 hemodialysed (HD) patients with CRI and were compared to those of 60 healthy volunteers (HV). In patients with CRI accumulation of 5HT and 5HIAA in plasma with no changes in platelet 5HT content was revealed. 5HT renal and fractional excretion (FE) was markedly decreased in CRI. FE-5HT was < 1 in all investigated subjects, indicating its reabsorption in p...
In the present study, the adherence of Staphylococcus aureus (strain 83254) and its RNAIII mutant (WA400) to immobilised fibrinogen and fibronectin, and to human endothelial cells (EC), was studied. [3H]Thymidine-labelled bacteria in... more
In the present study, the adherence of Staphylococcus aureus (strain 83254) and its RNAIII mutant (WA400) to immobilised fibrinogen and fibronectin, and to human endothelial cells (EC), was studied. [3H]Thymidine-labelled bacteria in stationary phase were incubated on the test surfaces for 20 min under static or flow (200/s) conditions. The results showed: (a) increased adherence of the RNAIII mutant to fibrinogen under static conditions, and decreased adherence of the mutant to fibronectin and EC under both static and flow conditions compared with the parental strain; (b) stronger ability of the mutant compared with the parental strain to induce platelet aggregation in suspension; (c) greater adherence of the parental strain and the mutant to EC pre-treated with platelet-rich plasma compared with platelet-poor plasma, and to EC pre-treated with platelet-poor plasma compared with control; (d) increased adherence of S. aureus to EC pre-treated with PMA-activated platelets and decreas...