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Biomedical subjects

J Kedziora

Publications and source records attributed to J Kedziora.

At least 55 records · Page 3Linked to original sources
PubMed1991

Decreased oxidant-induced proteolysis in erythrocytes with enhanced antioxidative defence enzymes due to Down's syndrome.

Erythrocytes of Down syndrome patients, having increased activity of superoxide dismutase and glutathione peroxidase, showed a similar increase in intracellular proteolysis upon stimulation with 1 mmol/l phenylhydrazine than normal erythrocytes. There were no differences in the magnitude of Heinz body formation following the treatment or in the proteolysis of exogenous oxidized substrate. These results demonstrate a protective role for endogenous antioxidative enzymes in the protein damage by oxidative stress which triggers intracellular proteolysis.

Adult↗
PubMed1991

Whole blood superoxide anion generation and efficiency of some erythrocyte antioxidant systems during recombinant human erythropoietin therapy of uremic anemia.

Six chronic uremic patients on regular hemodialysis treatment were given recombinant human erythropoietin (r-huEPO) in a dose of 50 U/kg of body weight intravenously thrice weekly for 14 weeks. Following r-huEPO therapy, unstimulated whole blood superoxide anion (O2) generation did not change significantly, while opsonized zymosan-stimulated whole blood O2 generation increased. At the same time, erythrocyte superoxide dismutase and, in particular, glutathione peroxidase activities were found to be reducing with concomitant lowering of erythrocyte malonyldialdehyde (MDA) concentrations and increase in plasma MDA concentrations.

Adolescent↗
PubMed1991

Effect of submaximal physical exercise on antioxidative protection of human blood platelets.

The study was performed on healthy volunteers subjected to submaximal physical exercise (75% VO2max). Activities of catalase (CT) (EC 1.11.1.6), glutathione peroxidase (GPO) (EC 1.11.1.9), superoxide dismutase (ZnCu-SOD) (EC 1.15.1.1) and malonyldialdehyde (MDA) concentration in blood platelets before and after physical exercise were estimated. Physical exercise was found to induce a significant increase in the blood platelet enzymes activity accompanied by lowering platelet MDA concentration and platelet aggregability. The obtained results suggest that physical exercise has some effect on platelet reactivity and on platelet antioxidative enzymes.

Adult↗
PubMed1991

[Generation of active oxygen compounds by whole blood granulocytes in patients with chronic renal failure].

In patients with chronic renal failure (crf) on conservative treatment whole blood granulocyte superoxide anion (O2-) generation was significantly decreased. Regular hemodialysis treatment did not induce its significant improvement. As granulocyte O2- generation determines production of other active oxygen compounds, this phenomenon may lead to the impairment of phagocyte bactericidal activity and increased susceptibility to infections in crf. Various methods of determination of active oxygen compounds give incomparable results.

Adolescent↗
PubMed1991

Effect of bed rest on the adenine nucleotides concentration in human blood platelets.

The effect of immobilization in bed on metabolism and function of human blood platelet was studied. Blood platelets taken from patients with bone fractures after long term bed rest (14 days and 28 days) demonstrated significantly reduced concentration of total adenine nucleotides (after 28 days reduction about 30%). This decrease of total platelet adenine nucleotides after immobilization in bed is probably caused by stimulation of platelet secretory process. Thrombin which released from control platelets 58.2% +/- 1.5% of total adenine nucleotides liberated decreased amounts (only 23.1% +/- 3.3% of total) of nucleotides from patient platelets isolated after 28 days of immobilization in bed. Loss of nucleotides from platelets was accompanied by slightly increased extent of platelet aggregation. It is concluded that during bed rest the reactivity of blood platelets (aggregation and release reaction) is stimulated.

Adenine Nucleotides↗
PubMed1990

Superoxide anion generation and lipid peroxidation processes during hemodialysis with reused cuprophan dialyzers.

In 11 chronic uremic patients superoxide anion (O2-.) generation and lipid peroxidation processes were determined during hemodialyses with cuprophan dialyzers used three times. Intradialytic changes observed during the first 20 min of hemodialysis, that is the period of the most marked alterations, with consecutive uses of the same dialyzer included: decreased whole blood O2-. generation at rest and following stimulation with opsonized zymosan, decreased reductions in the erythrocyte superoxide dismutase (SOD-1) activity, increased reductions in the plasma malonyldialdehyde (MDA) concentrations, and unchanged erythrocyte MDA concentrations. However, immediately before hemodialysis with third-used dialyzer whole blood O2-. generation at rest and following opsonized-zymosan stimulation, and erythrocyte SOD-1 activity were slightly, but statistically significantly, lower (p less than 0.05), while plasma MDA concentrations were higher (p less than 0.05) than those before hemodialysis with first-used dialyzer; erythrocyte MDA concentrations remained unchanged. The results seem to indicate that dialyzer reuse may exert beneficial effects on whole blood O2-. generation and protect erythrocyte membrane lipids from peroxidation, but, however, it leads to slightly increasing predialysis plasma lipid peroxidation.

Adult↗
PubMed1989

[Superoxide dismutase activity and malonic dialdehyde level in blood platelets of patients with coronary disease].

The investigations aimed at evaluating free superoxide radicals generation and the degree of blood platelets cell membrane lipids peroxidation on the base of superoxide dismutase activity and malonic dialdehyde level in patients with ischaemic heart disease. The obtained results have shown that blood platelets superoxide dismutase activity is markedly lower in patients with ischaemic heart disease than in healthy individuals whereas malonic dialdehyde levels are markedly higher.

Adult↗
PubMed1989

Superoxide anion generation, erythrocytes superoxide dismutase activity, and lipid peroxidation during hemoperfusion and hemodialysis in chronic uremic patients.

In 11 chronic uremic patients superoxide anion generation in whole blood, both without and with opsonized zymosan stimulation, was lower than that in 11 healthy controls, while erythrocyte superoxide dismutase (SOD-1) activity and erythrocyte and plasma malonyldialdehyde (MDA) concentrations were elevated. During hemoperfusion (HP) and hemodialysis (HD) superoxide anion generation transiently significantly increased. Changes in the erythrocyte SOD-1 activity and plasma and erythrocyte MDA concentrations during HP suggested that this procedure exerted beneficial effects on lipid peroxidation. On the other hand, during HD erythrocyte membrane lipid peroxidation seemed to be enhanced even further; this phenomenon took place mainly within the dialyzer and a decrease in the erythrocyte SOD-1 activity seemed to be one of the contributing factors. Results of in vitro experiments with cross-incubation of erythrocytes and blood plasma and incubation of whole blood with cuprophan membrane suggest existence of an SOD-1 activator in the uremic blood plasma, which is possibly eliminated during HD.

Adult↗
PubMed1989

[Effect of captopril on superoxide dismutase (SOD-1) activity and malondialdehyde (MDA) level in blood platelets in patients with arterial hypertension].

18 patients aged 40-50 with diagnosed hypertension (II class by WHO) underwent the study. SOD-1 activity, platelets MDA concentration and degree of platelets aggregation were estimated before and after 1.5 and 24 hours of administration of 12.5 mg captopril single dose. Values of evaluated parameters significantly changed after 1.5 hours of captopril administration: SOD-1 activity increased whereas MDA concentration and platelets aggregation decreased; after 24 hours of drug administration values returned to initial ones. It suggests inhibitory effect of captopril on lipids peroxidation and platelets reactivity.

Adult↗
PubMed1988

Down's syndrome: a pathology involving the lack of balance of reactive oxygen species.

Mongolism, or Down's syndrome (DS) is an inborn pathology due to trisomy 21. Apart from mental deficiency and anatomical abnormalities, premature aging is characteristic for this disease. This paper mainly reviews data on the generation of reactive oxygen species (ROS) and antioxidative defense mechanisms in DS, and on the sensitivity of DS cells to model sources of ROS. Changes in the antioxidative defense of DS cells are due mainly to the location of the gene for (Cu,Zn)-superoxide dismutase on chromosome 21. It is suggested that a disturbance of balance of ROS may be a key point in the pathogenesis of DS.

Aging↗
PubMed1987

[Effect of gamma radiation on the 2,3-diphosphoglycerate level of erythrocytes of healthy persons after submaximal physical exertion].

The authors studied the effects of gamma radiation and submaximal physical exercise on 2,3-DFG content in healthy men erythrocytes. Twelve men aged 20-22 were examined. They were loaded by physical exercise (at doses of 2 M/kg body weight) for 15 minutes. Erythrocytes were exposed to gamma radiation (500 Gy doses) from a 60Co source. The concentration of 2,3-DFG in erythrocytes was estimated by Bartlett's method. Gamma radiation at 500 Gy dose was found to decrease 2,3-DFG content in erythrocytes both at rest and after submaximal exercise. Furthermore, submaximal physical exercise was found to decrease 2,3-DFG content in non-irradiated erythrocytes.

2,3-Diphosphoglycerate↗
PubMed1987

[Effect of gamma radiation on fructose-1,6-diphosphate aldolase activity in the erythrocytes of healthy persons after submaximal physical exertion].

The authors studied the effects of gamma radiation and submaximal physical exercise on aldolase activity in healthy men erythrocytes. Twelve men aged 20-22 were examined. They underwent physical exercise at doses of 2 W/kg body weight for 15 minutes. Erythrocytes were exposed to gamma radiation (500 Gy doses) from 60Co source. The activity of aldolase in erythrocytes was estimated by Fermognost test. The submaximal physical exercise was indicated to increase the aldolase activity. Gamma radiation at 500 Gy dose was found to increase aldolase enzymatic activity in erythrocytes both a rest and after submaximal physical exercise.

Adult↗
PubMed1986

Lipid peroxides in blood plasma and enzymatic antioxidative defence of erythrocytes in Down's syndrome.

The level of lipid peroxides was significantly increased in the blood of patients with Down's syndrome. In erythrocytes increased activities of superoxide dismutase and glutathione peroxidase were confirmed while catalase activity was similar to that of healthy controls. The concentration of selenium in erythrocytes of Down's syndrome patients was reduced, in spite of increased glutathione peroxidase activity. These results confirm the hypothesis of an altered oxidative metabolism in Down's syndrome.

Catalase↗