M. Aoki

Simultaneous Determination of Carboxyhemoglobin and Methemoglobin in Victims of Carbon Monoxide Poisoning

Concentrations of methemoglobin (Met-Hb) and carboxyhemoglobin (HbCO) were simultaneously determined in blood samples from the victims of city gas poisoning, fires, and exhaust fumes poisoning. All the samples contained concentrations of HbCO, although the concentrations for victims of city gas poisoning were significantly higher than those for victims of fires or exhaust fumes poisoning. Only negligible amounts of Met-Hb were detected in the samples from cases of city gas poisoning, while 4.9 to 31.6% of Met-Hb were found in all but one (1.8%) of the samples of the other two cases. Heat denaturation was considered to be the main cause of Met-Hb production in cases of fires, and inhalation of oxides of nitrogen in cases of exhaust fumes poisoning.

A practical method for the accurate determination of methemoglobin in blood containing carboxyhemoglobin

Kinetics of the oxidation of carboxyhemoglobin (HbCO) by potassium ferricyanide was studied photometrically in a weakly acid solution. An increase in the absorbance at 630 nm reached a maximum within 10 min when over a 100-fold excess of ferricyanide to hemoglobin iron was used. A slight decrease in the absorbance was observed after completion of the reaction when over a 500-fold excess of the reagent was used. In the presence of 0.4% Sterox SE, the absorbance began to decrease without complete oxidation. From these findings, a simple, rapid and accurate method for the determination of methemoglobin (Met-Hb) in blood was devised. The method was compared with two other methods, using 11 blood samples containing various amounts of HbCO, and proved to be suitable for blood containing elevated HbCO as well as for ordinary blood.

Forensic application of rapid analysis of carboxyhemoglobin in blood using an oxygen electrode.

Blood carboxyhemoglobin (HbCO) levels in forensic victims were measured by a new and rapid oxygen-electrode method for successive determinations of HHb, HbO2 and HbCO. It was found that the method is applicable to old denatured blood when combined with the cyanmethemoglobin method. Methemoglobin (Met-Hb) in blood was also estimated by subtracting the sum of HHb, HbO2 and HbCO from total hemoglobin (total Hb.) Blood Met-Hb levels in six victims of city gas poisoning were practically negligible, while those in five victims of fire were 13.5-26.3%.

A simple spectrophotometric method for the determination of carboxyhemoglobin in blood

The spectrophotometric method for the determination of carboxyhemoglobin (HbCO) in blood reported by Fretwurst and Meinecke was modified so as to give the same values of percentage HbCO (HbCO%) as those determined by the oxygen electrode method. Values of HbCO% of nine practical samples determined by both the oxygen electrode method and the present method were nearly identical regardless of the presence of methemoglobin (Met-Hb) in blood. The present method is suitable for forensic practice.

Long-term storage of blood samples at freezing temperatures in the presence of a cryoprotectant for hemiglobin assay

Changes in Hi levels in experimentally prepared blood samples during storage at various temperatures were studied. When whole blood in which Hi levels were elevated by sodium nitrite was stored unfrozen, rapid reduction of Hi was observed within 24 hr even at 0 degrees C. When whole blood or a diluted hemolysate was stored frozen for a week or longer, considerable formation of Hi by autoxidation was observed, the formation at -20 degrees C being much more significant than that at -30 degrees C. On the other hand, addition of an equal volume of the cryoprotectant solution of Rowe et al. to blood almost completely inhibited this Hi formation during freezing storage until at least 30 days. Thus, a new method for long-term storage of blood samples for Hi assay was devised.

A new reagent for the rapid determination of total hemoglobin as hemiglobincyanide in blood containing carboxyhemoglobin

Kinetics of conversion of HbCO to HiCN with various K3Fe(CN)6-KCN reagents was examined photometrically. Complete conversion of HbCO to HiCN required about 8 hr, 150 min, and 50 min with Drabkins reagent, that of van Kampen and Zijlstra, and that of Taylor and Miller, respectively. The absorbance at 540 nm was stabilized practically in 5 min even in CO-saturated blood when a reagent containing a 1600-fold excess of K3Fe(CN)6 to Hb iron was used. A slight increase in the absorbance was observed around 504 nm in the HiCN solution produced with the reagent. The absorbance at 540 nm in the solution, however, was stable until at least 120 min after mixing. From these findings, a reagent containing a 1600-fold excess of K3Fe(CN)6 to Hb iron and an incubation time of 5 min were used for the complete conversion of HbCO to HiCN. The stabilization of the absorbance at 540 nm was often prolonged to 10 min when the reagent was stored over 2 weeks. The reagent was compared with two other reagents, using 20 blood samples containing various amounts of HbCO, and proved to be suitable for the determination of total Hb in blood containing elevated HbCO as well as in ordinary blood.

Hyperuricemia in rats during acute carbon monoxide poisoning.

The effect of carbon monoxide (CO) inhalation on plasma levels of uric acid and hypoxanthine in rats was investigated. Exposure to 3% CO caused respiratory arrest within about 2 minutes. The plasma uric acid level of CO-treated rats increased to 157% above that of ether-treated rats. When rats were exposed to 1% or 0.8% CO, the exposure periods until the onset of respiratory arrest were prolonged, and plasma uric acid levels at respiratory arrest were further elevated. Plasma uric acid levels at respiratory arrest increased with prolongation of the exposure periods. Under our experimental conditions, hypoxanthine or xanthine was not detected in plasma of CO-treated rats. These results are discussed in relation to the hyperuricemia in hemorrhagic shock or hypoxemia: CO-induced hyperuricemia can be attributed to the stimulated degradation of adenine nucleotides under tissue anoxia, and thus could be an excellent parameter of tissue anoxia.

Liver damage in rats during acute carbon monoxide poisoning

Plasma leucine aminopeptidase (LAP) levels and respiration rates of isolated liver mitochondria were studied in carbon monoxide (CO)-poisoned rats sampled at respiratory arrest. An increase in LAP levels paralleled a decrease in the respiratory control ratio and the ADP/O ratio. The results suggest that the damage to mitochondria closely correlates with the liver damage in rats during acute CO poisoning.

Phosphoglucomutase1and 6-Phosphogluconate Dehydrogenase Types in Human Skin and Adipose Tissue

Attempts were made to detect phenotypes of the enzymes phosphoglucomutase 1(PGM1) and phosphogluconate dehydrogenase (PGD) in human skin and adipose tissues. Both enzymes could be typed using approximately 3 mg wet weight of tissue. Phenotypes could be distinguished after up to 15 days of aging for PGM1 and ten days of aging for PGD. Analysis of isoenzymes is potentially useful for mediolegal identification of human skin and adipose tissue.

A simple and accurate method for measurement of the hemoglobin content in blood by colorimetric iron determination

SummaryA simple and accurate determination of iron in blood involving acid digestion in a heating block is described. The digestion requires little attention and permits the handling of large numbers of samples. The diluted digest is used for the colorimetric determination of iron using o-phenanthroline, and the equivalent hemoglobin in blood is calculated. There was a good correlation between the results of the present method and the cyanmethemoglobin method with 21 standard blood samples containing 4.9–26.8 g/dl of hemoglobin.ZusammenfassungEs wird eine einfache und genaue Methode zur Bestimmung von Eisen im Blut unter Verwendung von Säureaufschluß im Heizblock beschrieben. Der Aufschluß benötigt wenig Mühe und erlaubt die Verarbeitung einer großen Zahl von Proben. Der verdünnte Aufschluß wird zur kolorimetrischen Eisenbestimmung mittels o-Phenanthrolin benutzt und die entsprechende Hämoglobinkonzentration im Blut berechnet. Es zeigte sich eine gute Korrelation der Ergebnisse mit der beschriebenen und der Cyanmethämoglobin-Methode anhand von 21 Standardproben, die 4,9 bis 26,8 g/dl Hämoglobin enthielten.