The pH dependence of the electron paramagnetic resonance (EPR) spectrum and oxygen affinity of cobaltous porphyrin-containing myoglobin (CoMb) have been examined. The hyperfine structures of the EPR spectrum of oxy-CoMb undergo small, reversible pH-dependent changes with pK values of 5.33, 5.55, and 5.25 +/- 0.05 for proto-, meso-, and deutero-CoMb's, respectively, whereas deoxy-CoMb does not e...

BACKGROUND In models of smoke inhalation injury and carbon monoxide poisoning blood carboxy-hemoglobin (COHb) levels decrease faster than predicted by the generally recognized half-life of COHb. We studied the effects of duration of exposure to carbon monoxide (CO) on the subsequent CO elimination. METHODS Each of four sheep were insufflated with CO gas mixtures either for a few minutes (shor...

Proton 1H electron-nuclear double resonance spectra were obtained from cobalt-substituted hemoglobin A. For oxy cobalt-substituted hemoglobin (CoHb), two major couplings were found. One is exchangeable by deuterium and has a coupling of approximately 5.6 MHz which is assigned to the N epsilon 2-proton of the distal histidine (E7), interacting with the ligand. The other splitting (approximately ...

The purpose of this study was to determine if chronic exposure to low levels of carbon monoxide (CO) in man results In tissue hypoxia. For this reason, nine smokers (more than one pack of cigarettes per day) were studied. The presence of hypoxia was assessed by measurement of red cell mass (ACM). The effect of CO on lntraerythrocytic factors involved with oxygen delivery was determined by measu...

Using multiple samples collected via an indwelling venous cannula changes in blood carboxyhaemoglobin (COHb) were studied in five subjects before, during and up to 24 hr after smoking. On average the smoking, with inhalation, of one cigarette in 64 min raised the % COHb by 1-6, compared with 2-2 for 24 min of inhaled cigar smoking and only 0-2 for 20 min of non-inhaled pipe smoking. It is sugge...

Charcoal production is often accompanied with gaseous and particulate emission into the atmosphere and occupationally exposed workers could be affected. This cross sectional comparative study was carried out to assess the levels of carbon monoxide (CO), carbon dioxide (CO2), sulphur dioxide (SO2), nitrogen dioxide (NO2) and particulate matter (PM2.5) generated during the phases of charcoal prod...

We compared cotinine, carboxyhemoglobin, and thiocyanate concentrations in blood sampled from 187 cigarette smokers and 181 non-smokers. All three differed significantly between smokers and non-smokers. Cotinine performed best as a test for assessing smoking status, with a sensitivity of 98% as compared with 94% for carboxyhemoglobin and 80% for thiocyanate, all at a specificity of 95%. These d...