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G Kyriazis

Publications and source records attributed to G Kyriazis.

5 recordsLinked to original sources
PubMed1997

Clinical evaluation of four different high-flux hemodialyzers under conventional conditions in vivo.

Four types of high-flux hemodialyzers, Primus 2000 (high-flux polysulfone 2.0 m2), Altra-Flux 170 G (cellulose diacetate 1.7 m2), FLX-15 GW (polyester-polymer alloy 1.5 m2) and PAN-85 DX (polyacrylonitrile 1.7 m2) were evaluated in vivo. A total of 12 stable chronic hemodialysis patients participated in the study and each type of dialyzer was tested once in 9 of them. Blood samples for the measurement of BUN, creatinine, phosphate, uric acid, albumin and beta2-microglobulin (beta2M) were drawn before and 5 min after the end of the study dialysis. During dialysis, which was performed in all patients with a blood flow rate of 250 ml/min for 240 min, the dialysate (550-600 ml/min) was collected every hour and samples were drawn for the measurements of all the above substances. The mean total amount of low-molecular substances removed per session by each dialyzer was very close to 19.5 g for urea, 2.0 g for creatinine, 0.9 g for phosphate and 1 g for uric acid. The one-third (30-33%) of the above amounts were removed during the first hour of dialysis. Dialyzers' clearances for creatinine and uric acid were significantly higher in Primus dialyzer comparing to FLX-15 GW (p < 0.05) while the clearance for urea showed a borderline significance (p = 0.055). No difference was found either among Altra-Flux 170 G, FLX-15 GW and PAN-85 DX or between Primus and PAN-85 DX dialyzers. Phosphate clearance did not show any difference among the four dialyzers. The lowest amount of albumin removed per session was 0.75 g by PAN-85 DX and the highest 1.8 g by FLX-15 GW, while the equivalents for beta2M were 80 mg by Altra-Flux 170 G and 142 mg by PAN-85 DX. A significant adsorption of beta2M on these dialysis membranes was indicated by the combination of a satisfactory serum beta2M reduction ratio (post-/predialysis values = 0.52, 0.77, 0.60, 0.55) with a reduced beta2M clearance (23.9, 13.6, 20.2, 25.1 ml/min). During the first hour of dialysis, in comparison to the following time, the highest amounts of albumin and beta2M (expressed as percentage of total) were removed by the Primus 2000 dialyzer. Our results indicate that under conventional conditions small differences in the surface area of the high-flux dialyzers are unimportant regarding the removal of low molecules. However, the composition of the membrane seems to play an important role in the removal of high-molecular substances.

Acrylic Resins↗
PubMed1975

A simple staining method for vaginal smears using red ink.

In adult rhesus monkeys each phase of 37 menstrual cycles was accurately classified by cellular identification of vaginal smears stained with red ink. This technic was simple, quick, and inexpensive, and produced well-stained slides in a few seconds.

Animals↗
PubMedDate not supplied

Comparative efficacy of salbutamol and salmeterol in exercise-induced asthma.

This study compared the protection provided by salbutamol and salmeterol against exercise-induced asthma. Asthmatic patients (n = 12) with exercise-induced asthma were exercised submaximally for 6 min on a treadmill 1, 6 and 12 h after inhalation of 200 micrograms salbutamol or 50 micrograms salmeterol. Each patient also took baseline exercise 1 h after two puffs of placebo. Two days later the drugs were administered in a double-blind trial of crossover design with an interval of 48 h between the two treatments. The main parameters measured were: air flow with a Wright flowmeter and mediator concentrations (histamine, leucotriene and prostaglandin D2 measured by radioimmunoassay) in venous blood, which was withdrawn before and 4 min after each exercise period. The maximum percentage bronchoconstriction recorded following placebo was 29 +/- 4% and following salbutamol inhalation it was 4 +/- 4%, 20 +/- 13%, 27 +/- 10%, respectively, for the exercise periods performed 1, 6 and 12 h after inhalation of the drug. Following salmeterol, the corresponding figures were 3 +/- 4%, 3 +/- 3% and 11 +/- 9%. The concentrations of mediator in plasma were significantly increased after exercise. Salbutamol and salmeterol intake reduced these concentrations both when the patients were at rest and following the exercise period. This effect of both drugs on the mediators corresponded with the protection they provided against exercise-induced asthma and was maintained for 12 h after salmeterol inhalation and for 6 h after salbutamol inhalation.

Administration, Inhalation↗
PubMedDate not supplied

Superoxide dismutase activity in early and advanced Parkinson's disease.

Superoxide dismutase (SOD) is an enzyme system that is implicated in the oxidant stress model of Parkinson's disease (PD) pathogenesis. This study was designed to assess SOD activity in whole blood and red blood cells of PD patients in early and advanced stages of the disease. Fifteen PD patients in stage I and II (group A) and 15 in stage III and IV (group B) as well as 15 normal controls were included in the study. SOD activity was assessed in whole blood and red blood cells. Group B patients showed a statistically significant decrease of SOD activity in whole blood and in red blood cells. A negative correlation between SOD activity and duration of the disease was observed, while there was no relationship between L-Dopa treatment and SOD activity. Our results indicate that a defect in SOD activity develops over time in PD. Whether this is a later manifestation of antioxidant mechanism deterioration or simply an epiphenomenon remains unclear.

Aged↗