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Biomedical subjects

K Arashidani

Publications and source records attributed to K Arashidani.

At least 37 records · Page 2Linked to original sources
PubMed1993

Effect of side-stream cigarette smoke on the hepatic cytochrome P450.

The effect of inhalation of side-stream cigarette smoke on the hepatic microsomal cytochrome P450 was investigated Rats were placed in a chamber of 0.1 m3 in volume, in which cigarettes were burned at the rate of 1, 3, or 5 cigarettes per h, 8 h/day for 5 days. Cytochrome P450 and NADPH-cytochrome c reductase showed no significant changes; however, cytochrome b5 increased significantly. On the other hand, the activity of aryl hydrocarbon hydroxylase (AHH) decreased in the rats treated with a high concentration of cigarette smoke. In order to study the changes of isoforms of cytochrome P450, western blot analyses were performed. The inductions of three kinds of isoforms, cytochromes P450IA1, IA2, and IIB1, were demonstrated immunochemically. However, there were disagreements between the results of the western blot analyses and the measurements of total cytochrome P450 content and AHH activity.

Animals↗
PubMed1993

Personal exposure to nitrogen dioxide from indoor heaters and cooking stoves.

The personal exposure to NO2 generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO2 filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO2 concentration during the study period was 13.5-13.7 micrograms/m3. Smoking and the usage of electric heaters did not affect the exposure to NO2. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO2 concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 micrograms/m3, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO2 levels during cooking were calculated to be 290 micrograms/m3. Using these calculated values of NO2 concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO2 were associated with the increase of urinary HOP/C.

Adult↗
PubMed1993

Biological monitoring of toluene and DNA polymorphism in humans.

The effects of genetic polymorphism in aldehyde dehydrogenase 2 (ALDH2) on alcohol intakes and toluene metabolism were studied in workers who handle toluene. The genotypes of ALDH2 were divided into three groups, which were the homozygous genotype of normal ALDH2 (NN), the homozygous genotype of an inactive one (DD) and the heterozygous genotype of normal and inactive ones (ND), using the polymerase chain reaction (PCR) method in a solution containing ddGTP. The alcohol intake of the DD group was very small. On the other hand, the alcohol intake of NN group was higher than that of DD group. That of ND group was about half way between those of NN group and DD group. The alteration of toluene metabolism by the polymorphism of ALDH2 was not clear because the exposure levels of the workers to toluene were low.

Adult↗
PubMed1993

[Effects of methyl tertiary-butyl ether on hepatic lipid peroxidation in mice].

The effect of one-shot or repeated treatment with methyl tertiary-butyl ether (MTBE) on lipid peroxidation and cytochrome P-450 in mouse liver was examined. One-shot treatment at the 500 mg/kg dose level caused a transient decrease in leukocyte number after 24 h. An increased level of lipid peroxide was observed in the liver homogenates 24 h after one-shot treatment and four weeks of repeated 200 mg/kg treatment. The hepatic cytochrome P-450 content increased after one and four weeks of repeated treatment (50, 200 mg/kg). On the other hand, the treatment did not affect glutathione content and glutathione-S-transferase activity. These results indicate that MTBE treatment caused lipid peroxidation in the liver homogenate and induction of hepatic microsomal cytochrome P-450 content.

Animals↗
PubMed1992

The effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic gamma-glutamyl transpeptidase.

In this paper, we determined whether ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (diEGME) induce hepatic gamma-glutamyl transpeptidase activity. Male adult Wistar rats weighing 220 g were used as experimental animals. EGME (100, 300 mg/kg per day) and diEGME (500, 1000, 2000 mg/kg per day) were administered by gavage for 1, 2 or 5 days or 4 weeks. In the 4-week study, experimental animals were administered EGME or diEGME once a day orally, 5 days/week. EGME treatment increased the serum gamma-glutamyl transpeptidase (GGT) level significantly, however, diEGME did not. The activities of three other enzymes (SGOT, SGPT and ALP) in serum were not altered by EGME or diEGME treatment and thus there was no biochemical indices of hepatic damage by EGME or diEGME. EGME treatment increased the GGT activities in the liver and lungs. Of the organs examined, the induction of GGT was the greatest in the liver. The inducibility in the liver was 216% for the 5-day treatment and 460% for the 4-week treatment. A dose-dependent increase of hepatic microsomal GGT activity by EGME was observed. On the other hand, renal GGT activities were declined to 72% and 60% of control by the 5-day and 4-week EGME treatments, respectively. DiEGME did not affect the GGT activities in any of the tissues except those of the brain. In the histochemical study, most hepatocytes at the periportal zones were stained with GGT staining after the 4-week treatment. However, the hepatocytes at the central zones were negative.

Animals↗
PubMed1992

[A simple method for measuring cleaning solvent in air by gas detector tube for ethyl acetate].

A simple method for measuring cleaning solvent in air by gas detector tube for ethyl acetate was evaluated with regard to basic performance such as sensitivity, precision, discolor tone and effect of temperature. Satisfactory results were obtained with regard to sensitivity, precision, discolor tone in the indicator and stability of discolored length. Range of measurable concentration by the present method was about 25-800 mg/m3. It was found necessary in the present method to make temperature correction. It was concluded from these results that the present method is useful for measuring cleaning solvent in air. However, positive effect on discolored length was found by vapor of toluene and ethyl acetate when they coexisted. No effect on discolored length was found by vapor of acetone, methanol or trichloroethylene.

Acetates↗
PubMed1990

Effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic metabolizing enzymes.

Glycol ethers have been extensively used in industry over the past 40-50 years. Numerous studies on the toxicity of glycol ethers have been performed, however, the effects of glycol ethers on the hepatic drug metabolizing enzymes are still unknown. We studied the changes of the putative metabolic enzymes, that is, the hepatic microsomal mixed function oxidase system and cytosolic alcohol dehydrogenase, by the oral administration of diEGME and EGME. Adult male Wistar rats were used. DiEGME was administered orally; 500, 1000, 2000 mg/kg for 1, 2, 5 or 20 days and EGME was 100, 300 mg/kg for 1, 2, 5 or 20 days. Decreases in liver weights were produced by highest doses of diEGME (2000 mg/kg body wt/day for 20 days) and EGME (300 mg/kg body wt/day for 20 days). DiEGME increased hepatic microsomal protein contents and induced cytochrome P-450, but not cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was not affected by diEGME administration. On the other hand, EGME did not change cytochrome P-450, cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was increased by repeated EGME treatment. Therefore it is suspected that the enzyme which takes part in the metabolism of diEGME is different from that of EGME, although diEGME is a structural homologue of EGME.

Administration, Oral↗
PubMed1987

[Determination of 1-nitropyrene by high performance liquid chromatography--an analysis of diesel engine soot].

In the present paper, a method is described for the determination of nitroarene, (nitrated polynuclear aromatic hydrocarbons) in pollutants. Organic compounds in diesel engine soot samples were extracted with 10 ml ethanol and 40 ml benzene for 10 minutes by using a ultrasonic apparatus. The aromatic nitro compounds extracted were redissolved in methanol and converted to aromatic amines by using hydrochloric acid and zinc powder for 15 minutes. The reduced aromatic amines were extracted with benzene, and the extract was completely evaporated under nitrogen gas and then the residue was redissolved in cyclohexane. The reduced fraction in cyclohexane was chromatographed on a silica gel column and divided into two portions. The aromatic amino compounds were contained in the second fraction, which was eluted with benzene and was completely evaporated under nitrogen gas. On the other hand, the residue was redissolved in acetonitrile. The aromatic amino compounds in acetonitrile were separated and determined by means of high performance liquid chromatograph equipped with a UV and fluorescence detectors. In diesel engine soot samples, 1-nitropyrene, 9-nitroanthracene, and 1-nitrofluorene were detected. 1-nitropyrene could be determined and its content was 59-1020 ng/g. By this method, 1-nitropyrene in pollutants could be analyzed easily.

Air Pollutants↗
PubMed1986

[Distribution and morphological characterization of chemical substances in environment. 1. Simplified analytical methods and distribution of environmental pollutants in Kitakyushu City].

This paper describes an analytical method for determining polynuclear aromatic hydrocarbons (PAHs) and nitroarene as well as the distribution of chemical substances in airborne particulates, soils and sediments. Our paper consists of the following chapters. Introduction Separation and determination of PAHs Purification and determination of PAHs in airborne particulates. Mutagenicity of airborne particulates. Monitoring of air pollutants in Kitakyushu city. Analysis of 1-nitropyrene. Analysis and determination of PAHs in soils and sediments.

Air Pollutants↗