Background: Malaria remains the world’s most devastating human parasitic infection. Our goal was to assess the capacity of increasing concentrations of five antimalarial drugs (Fansidar, Halfan, Quinine, Coartem and Chloroquine phosphate) to elicit the generation of methemoglobin in three human erythrocyte genotypes (Hb AA, Hb AS and Hb SS). Materials and Methods: Spectrophotometric method was ...

In vitro studies have demonstrated pro-oxidant effect of ascorbic acid on sheep erythrocyte hemolysate and on purified ruminant hemoglobin preparations. Methemoglobin formation was concentration dependent over ca. 3.4 through 34 μmole ascorbic acid with sheep hemolysate (r=0.97, p<0.01, n= 3 each) and over ca. 5.68 through 22.7 μmole ascorbic acid with purified ruminant Hb preparations (r >0.99...

BACKGROUND A new eight-wavelength pulse oximeter is designed to measure methemoglobin and carboxyhemoglobin, in addition to the usual measurements of hemoglobin oxygen saturation and pulse rate. This study examines this device's ability to measure dyshemoglobins in human volunteers in whom controlled levels of methemoglobin and carboxyhemoglobin are induced. METHODS Ten volunteers breathed 50...

BACKGROUND AND OBJECTIVE One goal of anesthesia for renal transplantation is to avoid an excess load to be imposed on the newly functioning kidney, by using appropriate agents and dosages in the perioperative management. The purpose of this study was to investigate the effect of prilocaine on serum methemoglobin levels when used as the local anesthetic in epidural anesthesia for renal transplan...

The reaction of nitrite with deoxyhemoglobin results in the production of nitric oxide and methemoglobin, a reaction recently proposed as an important oxygen-sensitive source of vasoactive nitric oxide during hypoxic and anoxic stress, with several animal studies suggesting that nitrite may have therapeutic potential. Accumulation of toxic levels of methemoglobin is suppressed by reductase enzy...

The electrophoretic mobility of erythrocyte NADH methemoglobin reductase in five hereditary methemoglobinemia patients from three Puerto Rican kindreds was 118% of normal at pH 8.6. The methemoglobin ferrocyanide reductase activity of the enzyme in erythrocyte hemolysates was 3.2-6.4% of normal. Electrophoresis of hemolysates prepared from the blood of patients from two different families at si...

Oxyhemoglobin in erythrocyte hemolysates interferes with the Jendrassik-Grof assay. Destruction of azobilirubin occurs when oxyhemoglobin is oxidized to methemoglobin during diazotization or to alkaline hematin with addition of alkaline tartrate. The most probable mechanism is by oxidation with an agent such as hydrogen peroxide or a related species resulting from hemoglobin oxidation. Methemog...

By PHILIP L. TOWNES AND MARTIN MomusoN A VARIANT of hereditary methemoglobinemia exhibiting dominant inheritance of normal methemoglobin has recently been reported? Although the TPN and DPN methemoglobin reductases were found to be normal, an inability to utilize glucose for the reduction of methemoglobin was demonstrated. The present report describes further attempts to define more definitely ...

IT IS \VELL KNO\VN that a number of chemical agents, w’hieh under certain circumstances cause intravascular hemolvsis an(l the development of hemolytic anemia, also produce methemoglobinemia. Some examples of these agents are stllfanilam ide, phenylhydrazine, aniline , acetanilid, p-aminophenol , plasmochin, etc. Such a correlation may lead to the inference that intracorpu.scular methemoglobin ...

The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The...