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Biomedical subjects

R Nanikawa

Publications and source records attributed to R Nanikawa.

At least 19 recordsLinked to original sources
PubMed1990

The movement of blood formaldehyde in methanol intoxication. II. The movement of blood formaldehyde and its metabolism in the rabbit.

The movement of blood formaldehyde in rabbits that were intoxicated with methanol has been investigated by simple headspace gas chromatography-mass spectrometry for the microdetermination of formaldehyde in the blood. When methanol alone was administered to rabbits orally, formaldehyde could not be detected in the blood. Further, in an experiment on the metabolism of methanol in vitro, formaldehyde was not detected in specimen samples but formate was. In contrast, when methanol was orally administered to rabbits that had been pretreated with diethyldithiocarbamate (DDC), an aldehyde dehydrogenase (ALDH) inhibitor, 17 to 33 microM of formaldehyde were detected in the blood 4 hours later. However, formaldehyde was not detected in the blood when methanol was orally administered to rabbits that had been pretreated with pyrazole, an alcohol dehydrogenase (ADH) inhibitor. After rabbits were given an intravenous administration of formaldehyde, and on the addition of formaldehyde to a rabbit liver homogenate and blood, the formaldehyde in both instances was metabolized rapidly. Formaldehyde that was not metabolized within 10 to 15 minutes, however, bound to the tissue proteins. Therefore, according to the results of this study, formaldehyde was seen to be rapidly metabolized to formate without accumulating in the blood or binding to the tissue proteins. Formaldehyde thus appears to have little influence on the symptoms of methanol poisoning.

Animals↗
PubMed1990

Interactive effect of ethanol administration on blood hydroxyzine levels in rabbits.

Mechanism of a rise of blood hydroxyzine concentrations (BHC) due to ethanol administration was investigated used rabbits. When 10 mg/kg hydroxyzine dihydrochloride were orally administered together with 10 ml/kg of 1 to 15% ethanol solution, BHC raised in all rabbits given ethanol solution more than 10%. When 10 ml/kg of 15% ethanol solution were orally administered at 1, 2 or 3 hours before oral administration of hydroxyzine, BHC raised markedly in all cases. BHC raised little or a little when hydroxyzine were orally administered immediately after intravenous administration of 5 ml/kg of 20% ethanol solution. It was considered that the main mechanism of a rise of BHC was not metabolic interaction between hydroxyzine and ethanol, but an enhancement of intestinal absorption of hydroxyzine due to ethanol. It was also found that hydroxyzine in blood distributed rapidly into bodily tissues.

Animals↗
PubMed1990

Effect of ethanol on acute paraquat toxicity in rabbits.

The effects of simultaneous administration of ethanol and paraquat on the blood paraquat levels and fatality in rabbits were investigated to evaluate the role of alcohol ingestion in inducing susceptibility to paraquat intoxication. Paraquat alone and with the combination of ethanol were administered orally to rabbits. Rabbit mortality rates for the 24 h period following the ingestion of paraquat alone and paraquat combined with 2.0 and 3.8 g/kg of ethanol, were 0/8, 4/8 and 8/8 subjects, respectively. Animals which ingested paraquat and ethanol at 2.0 and 3.8 g/kg showed significant elevation of blood paraquat levels. Furthermore, an animal dosed with ethanol 2 h following the ingestion of paraquat, consequently, exhibited a marked increase in paraquat levels in the blood 0.5 h after the administration of the ethanol. On the other hand, the average values of Tmax, Cmax, and AUC 8-8 h of paraquat in rabbits dosed simultaneously with paraquat (200 mg/kg) and ethanol, at 2 g/kg, were 1.38 +/- 0.52 h, 28.11 +/- 14.08 micrograms/ml, and 108.97 +/- 39.54 micrograms/ml.h, and at 3.8 g/kg of ethanol, were 2.20 +/- 1.10 h, 47.61 +/- 19.15 micrograms/ml, and 194.43 +/- 53.82 micrograms/ml.h, respectively. These values were significantly higher than those for the rabbits dosed with 200 mg/kg of paraquat alone (Tmax, Cmax, and AUC 0-8 h were 0.94 +/- 0.18 h, 13.81 +/- 2.71 micrograms/ml, and 44.1 +/- 8.6 micrograms/ml.h, respectively). These results show a close correlation between blood paraquat levels in rabbits dosed simultaneously with ethanol and mortality rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1989

Determination of MN blood group from blood stains by electrophoresis and immunoblotting.

The determination of blood groups from blood stains is extremely important in medicolegal practice, but there is the possibility of an error in the determination of MN phenotypes by the absorption-elution test. We investigated a new method applying electrophoresis and immunoblotting. As a consequence of various experiments, the most appropriate pretreatment of blood stains was as follows. Blood stains were immersed in physiological saline for 0.5 to 1 h and centrifuged. The supernatant was discarded. The sediment was dissolved in sample buffer (TRIS-buffered physiological saline containing 2% sodium dodecyl sulfate) and followed by thermodegradation. It was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After transfer to a nitrocellulose membrane by Western blotting, MN phenotypes could be determined accurately from blood stains by an enzyme immunoassay (EIA) using commercially available polyclonal anti-M and anti-N sera. For blood stains more than 1 month old it was not easy to determine the MN phenotypes.

Blood Grouping and Crossmatching↗
PubMed1989

Experimental studies on effects of long-term ethanol administration on meprobamate elimination from blood.

When rabbits were administered different amounts of ethanol during 25 and 50 days, the elimination of meprobamate from blood was not accelerated at daily ethanol dose of 0.4g/kg. The elimination was accelerated a little at daily ethanol dose of 0.8g/kg and markedly accelerated at the dose of 1.6g/kg. However, it was not accelerated furthermore at the dose of 2.4g/kg. Thus, accelerative effect of long-term ethanol administration on meprobamate metabolism may be greatly related to ethanol dosage and it is considered that the accelerative effects reach maximum at blood ethanol concentrations more than 1mg/ml. Also, elimination of meprobamate from brain in rats was fairly accelerated by long-term ethanol administration at the daily dose of 0.4g.

Animals↗
PubMed1989

The movement of blood formaldehyde in methanol intoxication. I. A simple headspace gas chromatography-mass spectrometry for determining the amount of formaldehyde in the blood.

A gas chromatographic-mass spectrometric method for determining the amount of formaldehyde in the blood has been investigated. This method is based on the formation of diethoxymethane, which results from the reaction of formaldehyde with ethanol while in an acid state. The calibration curve in blood specimens showed a good linearity in the range of 20 to 100 microM formaldehyde with a correlation coefficient of 0.996. The minimum detectable amount of formaldehyde in the blood was found to be 10 microM and this analytic method was deemed useful for microanalysis of formaldehyde in blood.

Formaldehyde↗
PubMed1989

Interactive effects of acute ethanol administration on meprobamate levels in blood and brain of rabbit and rat.

In the simultaneous administration of meprobamate and ethanol to rabbits, the blood meprobamate concentration (BMC) increased greatly when the maximum blood ethanol concentration (BECmax) exceeded 1.0 mg/ml. Thus, we subjected the rabbits to continuous infusion of ethanol so as to make the blood ethanol concentration (BEC) constant and administered meprobamate by intravenous injection. Elimination of meprobamate became slow at about the BEC of 0.5 mg/ml and the degree reached almost maximum around the BEC of 1.0 mg/ml. The elimination rate did not change any more even when the BEC was raised higher. In the study conducted to elucidate the relationship between the BMC and brain meprobamate concentration (BrMC) using rats, it was found that meprobamate would show similar movements and its level would rise extremely by an acute administration of ethanol. It was indicated that the effect of ethanol on reinforcement of meprobamate activity would appear strongly by potentiation effect.

Animals↗
PubMed1988

Experimental studies on the mechanism of ethanol formation in corpses.

Various in vitro experiments were performed for the purpose of clarifying the mechanism of ethanol production in corpses. Whereas a negligible quantity of ethanol was produced in the blood alone, which was left at room temperature, the quantity of ethanol was slightly increased by addition of glucose to the blood. When saprogens were further added, the quantity was markedly increased. Various materials were added to blood-liver homogenates as specimens, and the mixtures were stored in an incubator at 37 degrees C. As a result of the addition of an antibiotic to the mixture every day, there was hardly any production of ethanol. When alcohol dehydrogenase (ADH) and reduced nicotinamide adenine dinucleotide (NADH) were added, ethanol production was slightly increased. When acetaldehyde was added first, ethanol production was inhibited the next day, but on and after day 2, the quantity of ethanol was more than that in the control material. When pyruvic acid was added first, the results were similar to the above. Pyrazole, cyanamide, and disulfiram completely inhibited the production of ethanol. Ethanol production in corpses is believed to take place through a pathway opposite to that of ethanol metabolism in the living body, under the influence of ADH, ALDH, etc., in saprogens using carbohydrates as substrates.

Acetaldehyde↗
PubMed1984

Genetic polymorphism of factor B (Bf) in Okayama Prefecture, Japan.

The genetic polymorphism of factor B (Bf) was investigated in Okayama Prefecture, Japan. Cellogel immunofixation electrophoresis was employed according to Martin and Ziegler (1981) with minor modifications. In 316 non-blood related Japanese, the Bf was: Bf S, 70.6%; Bf FS, 27.8%; and Bf F, 1.6%. No rare variants were observed. The gene frequencies of Bfs and BfF were 0.845 and 0.155, respectively. The gene frequencies in Okayama Prefecture were quite similar to those in other districts of Japan. Considering the phenotype distribution in Japan, the Bf system might be a useful marker for personal identification and in disputed paternity cases.

Complement Factor B↗