methemoglobin


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Related to methemoglobin: methemoglobin test, Methemoglobin reductase

methemoglobin

[met‚hē·mə′glō·bən]
(biochemistry)
References in periodicals archive ?
A co-oxymeter is a spectrophotometer that measures light absorption at four different wavelengths and thus differentiates various forms of hemoglobin (oxyhemoglobin, deoxyhemoglobin, methemoglobin, and carboxyhemoglobin) (6).
(2013), the amount of nitrate ingested and methemoglobin formed influences the period of time between disease progression and death.
Where methemoglobinemia occurs and methemoglobin levels exceed 30%
Methemoglobin - Induced by carcinogenic aminoazo dyes in rats.
Abbreviations CPZ: Chlorpromazine PS: Phosphatidylserine AchE: Acetylcholinesterase RBCs: Red blood cells PB3: Band 3 protein Hb: Hemoglobin GEs: Glycolytic enzymes G6P: Glucose-6-phosphate PPP: Pentose phosphate pathway HOS: High-oxygenation state LOS: Low-oxygenation state DNPH: 2,4-Dinitrophenylhydrazine p-NPP: p-Nitrophenylphosphate Met-Hb: Methemoglobin PMSF: Phenylmethanesulfonylfluoride NBT: Nitroblue tetrazolium PMS: Phenazine methosulphate t-BHT: tert-Butyl-hydroperoxide EDTA: Ethylenediaminetetraacetic acid TBARS: Thiobarbituric acid reactive substances OV: Orthovanadate DNP: Dinitrophenyl FACS: Fluorescence-activated cell sorting SD: Standard deviation pHi: Cytoplasmic pH.
In 2005, Masimo introduced rainbow Pulse CO-Oximetry technology, allowing noninvasive and continuous monitoring of blood constituents that previously could only be measured invasively, including total hemoglobin (SpHb(R)), oxygen content (SpOC(TM)), carboxyhemoglobin (SpCO(R)), methemoglobin (SpMet(R)), and Pleth Variability Index (PVI(R)), in addition to SpO2, pulse rate, and perfusion index (PI).
Methemoglobinemia: Monitor methemoglobin levels in patients with cardiopulmonary disease, hemoglobinopathy, or methemoglobin reductase deficiency Agranulocytosis: Monitor CBC count 4-10 wk after initiation of therapy; stop therapy when WBC count < 4000/[mm.sup.3] Peripheral neuropathy: Periodic neurologic screening examination by dermatologist; any suspected abnormality needs referral for full neurologic examination and electromyogram with nerve conduction studies Psychosis: Manifested by insomnia, irritation, excitability, and even violence; reversible on stopping dapsone CBC count, Complete blood cell count; Hb, hemoglobin; WBC count, white blood cell count, G6PD Glucose-6-phosphate dehydrogenase.
The MRI signal appearance of SDH evolves over time: The acute clot is hypointense on T2-weighted images due to the presence of deoxyhemoglobin, over subsequent weeks, deoxyhemoglobin degrades to methemoglobin which appears bright on both T1 and T2-weighted images, at several months, only hemosiderin remains, and the clot again becomes hypointense on the T1-weighted images.
Nitrate by the enzyme "nitrate reductase" (in the saliva, in the stomach, and everywhere in the human bodywhere pH is low) converts to nitrite; nitrite reacts with hemoglobin and produces methemoglobin which enables transporting of oxygen at the cellular level.
When high levels of nitrite accumulate, they are absorbed into the bloodstream where they change hemoglobin to methemoglobin, a condition known as methemoglobinemia.
Furthermore, manufacturers usually add human methemoglobin to test the effect of "hemoglobin" as an interferent.
When the parent compounds (prilocaine and lidocaine) were incubated with human liver microsomes (HLM), methemoglobin (Met-Hb) formation was lower than when the hydrolyzed metabolites were incubated with HLM.