The electron spin resonance technique shows that the heat denaturation of oxyhemoglobin involves (a) oxidation to methemoglobin or related material (high spin ferric), (b) conversion to low spin ferric species in an irreversible step, and (c) further changes in these low spin species under drastic conditions. The last two occurrences are observed with methemoglobin. The electron spin resonance ...

Methemoglobinemia and hemolytic anemia are the most prominent side-effects of a wide variety of arylamine drugs including agricultural and industrial chemicals. Symptoms of this hemotoxicity include headache, fatigue, dizziness respiratory and cardiac arrest, and possibly death. Parent compounds are usually converted to their toxic metabolites (N-hydroxylamine) and react with oxyhemoglobin with...

Pyridoxylated normal adult human hemoglobin (HbAo) has been prepared using both oxygenated and deoxygenated HbAo at pH 6.8 and room temperature without the addition of Tris to produce a mixture with P50 of 30 +/- 2 torr and a Hill coefficient of 2.3 +/- 0.1 similar to that of the isolated adult human hemoglobin from the red blood cell. Reduction of the pyridoxylated HbAo in the oxygen-ligated f...

Background: Our paper aimed to investigate whether there was a correlation among the pulse oximetry, cerebral oximetry (CO) and MetHb (methemoglobin) values of a patient with congenital methemoglobinemia who underwent a laparoscopic cholecystectomy operation. Case: The 35year-old male patient with a weight of 70 kg, body massindex (BMI) of 21, American Society of Anesthesia status-2(ASA-2) cate...

Responses to exchange transfusion with red blood cells (RBCs) containing methemoglobin (MetRBC) were studied in an acute isovolemic hemodiluted hamster window chamber model to determine whether oxygen content participates in the regulation of systemic and microvascular conditions during extreme hemodilution. Two isovolemic hemodilution steps were performed with 6% dextran 70 kDa (Dex70) until s...

Nitrite intoxication occurs frequently in ruminants and equines. The most common treatment of this disorder is administration of 1% methylene blue, although the use of some antioxidant agents e.g. vitamins and complementary treatment may also be useful. The aim of this study was to evaluate the in vitro antioxidative effects of some vitamins on methemoglobinemia induced by sodium nitrite. For t...