Janousek S.J.,National Institute of Public Health |
Rosa L.,Kralovske Vinohrady Faculty Hospital |
Jirova D.,National Institute of Public Health |
Kejlova K.,National Institute of Public Health
International Journal of Laboratory Hematology | Year: 2010
Washed red blood cells (RBCs), supplemented or non-supplemented with sodium azide (to inhibit catalase activity), were exposed to different concentrations of hydrogen peroxide as well as ascorbic acid. Strikingly, catalase within RBCs protected the cells against exogenic hydrogen peroxide even at millimolar concentrations. However, the activity of the erythrocytic catalase failed to protect the RBCs when they were exposed to an oxidative burst of stimulated polymorphonuclear cells (PMNCs) in the presence of several reactive species in addition to peroxide. Oxyhemoglobin, with an excess of hydrogen peroxide, formed oxidized hemoglobin species and caused protein denaturation as well as the rise of heme degradation products which was suspected to falsify zinc protoporphyrin/heme (ZPP/heme) ratio as assessed by hematofluorometry. Our experiments may thus imply that the non-fluorescent hemoglobin background can be modified by reactive oxygen species (ROS) and this can lead to a spurious ZPP/heme ratio. We discuss this phenomenon with respect to ZPP quantification in clinical practice.
Naar J.,Na Homolce Hospital |
Malek F.,Na Homolce Hospital |
Lang O.,Kralovske Vinohrady Faculty Hospital |
Belohlavek O.,Na Homolce Hospital |
And 4 more authors.
Vnitrni Lekarstvi | Year: 2014
Study objective: To compare parameters of diastolic function as assessed by radionuclide ventriculography (RNVG) and Doppler echocardiography (ECHO) in the patients with chronic heart failure and reduced ejection fraction (HF REF). Patients and methods: RNVG and ECHO were performed on the same day in 40 patients with systolic chronic HF, NYHA II and III, with LV EF < 50% and sinus rhythm, followed at tertiary HF clinic. Diastolic function was assessed by RNVG using parameters: PFR (peak filling rate [% SV/sec]), TFR - time to peak filling rate (ms), and by ECHO using pulse Doppler parameters: the peak Doppler velocities of early (E) and late diastolic flow (A), the E/A ratio, the calculated mean of the early (E′) diastolic velocity of septal and lateral mitral annulus measured by tissue Doppler imaging, and the E/E′ ratio. Results: The mean PFR was 421.7 (median 371.0) % SV/sec and TPF was 198.7 ms (median 169.5), the mean E/A ratio was 1.21 (median 0.85) and the E/E′ ratio was 9.0 (median 8.40). TPF correlated significantly (inverse correlation) with the E/A ratio (r = -0.34, p = 0.030), and not significantly with E′ (r = -0.27, p = 0.082), the PFR/age ratio correlated with the E/E′ ratio (r = -0.31, p = 0.05). Conclusion: Significant correlations of parameters of diastolic function as assessed by radionuclide and Doppler studies were identified in the HF REF patients.