. . . "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."@en . "J\u00EDrov\u00E1, Dagmar" . "Oxidative stress may modify zinc protoporphyrin/heme ratio in hematofluorometry" . "Janou\u0161ek, Stanislav" . . "10"^^ . . "1p2" . . . "3"^^ . . "Rosa, L." . "RIV/75010330:_____/10:00008185" . . "International journal of laboratory hematology" . . "000275511300006" . "oxidative stress; zinc-protoporphyrin"@en . "Oxidative stress may modify zinc protoporphyrin/heme ratio in hematofluorometry"@en . . "Kejlov\u00E1, Kristina" . . . "277879" . "P(NS9802)" . "1751-5521" . "RIV/75010330:_____/10:00008185!RIV11-MZ0-75010330" . "5"^^ . "GB - Spojen\u00E9 kr\u00E1lovstv\u00ED Velk\u00E9 Brit\u00E1nie a Severn\u00EDho Irska" . "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." . . . . "Janou\u0161ek, S. J." . "32" . "Oxidative stress may modify zinc protoporphyrin/heme ratio in hematofluorometry"@en . "[DC904213FD73]" . "Oxidative stress may modify zinc protoporphyrin/heme ratio in hematofluorometry" .