Publications by authors named "Kopelias I"

Urea kinetic modeling (Kt/V) is used to assess adequacy of hemodialysis (HD). However, serial Kt/V measurements may vary with time in the same patient, making the interpretation of the results difficult. The aim of the present study was to find the frequency and the causes that account for these fluctuations of Kt/V.

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A rise in intracellular calcium concentration in erythrocytes has multiple effects on these cells. The purpose of this study was to determine the changes of calcium content in red blood cells (RBCs) and of echinocyte percentages in uremic patients during hemodialysis sessions. In 30 uremic patients under hemodialysis, the calcium content of RBCs and echinocyte percentages were determined in 3 blood samples collected at 0 min hemodialysis (prehemodialysis), 45 min hemodialysis, and 240 min hemodialysis (end hemodialysis) for a 4 h hemodialysis session.

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The purpose of this study was to determine the changes of calcium and potassium content in red blood cells (RBC) from uremic patients during a hemodialysis (HD) session. In 17 uremic patients on HD, the calcium and potassium content of RBC was determined in 3 blood samples collected at 0 min-HD (pre-HD), 45 min-HD, and 240 min-HD (end-HD) during a 4 h HD session. The calcium and potassium content of RBC also was determined in 20 normal subjects (controls).

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It has been reported recently that a number of cytokines, mainly tumor necrosis factor alpha (TNFalpha), interleukin (IL)-1beta, and IL-6, can alter lipid metabolism and produce hyperlipidemia. Studies in hemodialysis (HD) patients have demonstrated increased production of these cytokines during HD. In order to investigate any possible relationship between changes of cytokines and lipid concentrations during HD in the serum of 25 uremic patients on chronic HD using modified cellulose membranes, TNFalpha, IL-1beta, IL-6, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), lipoprotein a (Lp[a]), and total proteins were measured immediately before (pre-HD) and after HD (post-HD), in one session.

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Home hemodialysis (HD) for the treatment of patients with end-stage renal disease (ESRD) was first put into practice about 30 years ago. In this paper we describe the application of telematics monitoring services (TMS) for supporting patients who need home or satellite HD (SHD). For the clinical trials two modified HD machines were located in the renal unit and a central control station (UNIX workstation with multimedia PC-terminal) was located in another room of the hospital.

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Home hemodialysis (HD) for the treatment of end-stage renal disease was first implemented about 30 years ago. In this paper the application of telematics monitoring services for supporting patients who need home HD or satellite HD is described. Two modified HD machines were located in two renal units, and a central control station (CCS, UNIX workstation with multimedia PC terminal) was located in another room of the hospital.

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We measured blood ammonia in pre-angioplasty samples from the renal veins, aorta and inferior vena cava of 15 patients with hypertension due to unilateral renal artery stenosis confirmed by arteriography. Patients with renal insufficiency or small kidneys were excluded. Mean ammonia values were microgram/dl: vein of affected kidney, 106.

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Graft artery stenosis is one of the main causes of hypertension in renal transplant recipients. We present a rare case of severe common iliac artery stenosis, proximal to the graft artery, that was the cause of accelerated hypertension and claudication in a male renal transplant recipient. After percutaneous balloon angioplasty combined with a Palmaz stent implantation, a dramatic improvement of hypertension and claudication was observed during a 10-month follow-up period.

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In this study the ammonia concentration was determined in arterial and venous blood samples pre- and posthemodialysis (HD) in 18 uremic patients and in 18 health subjects (controls). The mean values (+/- SD) of ammonia in the arterial blood of uremic patients pre-HD were 98.32 +/- 26.

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In 18 uremic patients under regular hemodialysis (HD) with bicarbonate dialysate, the echinocytes and erythrocyte sedimentation rates (ESR) were determined in 4 blood samples collected from the arterial line at 0, 45, 120, and 240 min (end-HD) in one HD session by a bioincompatible dialyzer and in another by a biocompatible one. In the HD session by a bioincompatible dialyzer, the mean values (+/- SEM) of echinocytes (%) at 0, 45, 120, and 240 min were 8.89 +/- 1.

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The safety and effectiveness of a low molecular weight heparin (LMWH) of 4500 +/- 1500 Daltons were evaluated in eight hemodialysis (HD) patients, in comparison with unfractionated heparin (UFH). In phase A of the study 3000 +/- 500 anti-factor Xa (AFXa) IU of LMWH were administered in bolus for the three consecutive HD sessions of a week. In phase B, 10000 +/- 2500 IU of UFH were administered to the same patients for the same time.

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Isolated rabbit lungs were perfused with washed and resuspended human red blood cells (RBCs) in the presence of drugs known to change the shape and deformability of RBCs. With sodium salicylate (0.5-2 g/l), which causes echinocytosis and increases RBC deformability, lung diffusing capacity for O2 (DLO2) increased by 21%.

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Abnormal glucose metabolism in uremia may result from a complex interplay between decreased insulin secretion and insulin resistance. Recent studies report beneficial effect of biotin administration in glucose metabolism in diabetic animals and in a small number of patients with diabetes mellitus. The aim of the present study was to evaluate the response of oral glucose tolerance test (OGTT) to the i.

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