Rats were fed diets prepared with soybean oil (SO), perilla oil (PO), or fish oil (FO) for 4 weeks, and some of the rats received daily s.c. injections (100mg/kg) of p-chlorophenoxyisobutyric acid (clofibric acid) for 1 week before being killed. The levels of serum triacylglycerol and cholesterol were conspicuously lower in FO-fed rats than in SO-fed rats. The administration of clofibric acid further decreased serum levels of triacylglycerol and cholesterol in SO-fed rats, but not in FO-fed rats. The decreased level of these serum lipids with FO-feeding alone were comparable to those observed in SO-fed rats which had received clofibric acid. The activity of peroxisomal β-oxidation in the liver of FO-fed rats was significantly higher (2.48 times) than that of SO-fed rats. The treatment of FO-fed rats with clofibric acid caused an additional increase in activity, as compared to the SO-fed control. The activity of peroxisomal β-oxidation in SO-fed rats treated with clofibric acid was 3.74 times that of the FO-fed control. In contrast to peroxisomal β-oxidation, the activities of catalase, glutathione (GSH) peroxidase towards hydrogen peroxide and GSH reductase were not increased by clofibric acid, regardless of the type of oil ingested. Moreover, the activities of GSH S-transferases towards 1-chloro-2, 4-dinitrobenzene (CDNB) and 1, 2-dichloro-4-nitrobenzene (DCNB) were both depressed to the same level by the administration of clofibric acid, regardless of the type of dietary oil, although FO-feeding significantly increased the activity of GSH S-transferase towards CDNB. PO comprises essentially the same effects on the parameters tested, to a lesser extent, compared with FO. Consequently, FO-feeding can reduce the dose of clofibric acid required to lower serum lipids, which concomitantly may prevent hepatocytes from oxidative stress that might be caused by an imbalance of hydrogen peroxide metabolism due to the increased activity of peroxisomal β-oxidation and to the decrease in the activities of detoxification by GSH S-transferase.

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Diesel-engine exhaust and airborne particulates were collected in downtown and suburban areas and five mutagenic nitroarenes (2-nitrofluoranthene (NF), 1-, 2- and 4-nitropyrenes (NPs) and 6-nitrochrysene (NC) in benzene-ethanol extracts were determined by high-performance liquid chromatography with chemiluminescence detection. 1- and 4-NPs and 6-NC were found in diesel-engine exhaust particulates, however, 2-NF and 2-NP were not detected. On the other hand, all five nitroarenes were found in airborne particulates. Diurnal concentration patterns of 4-NP and 6-NC in the downtown area were similar to the pattern of 1-NP, but the patterns of 2-NF and 2-NP were different from the pattern of 1-NP. These results strongly suggested that 2-NF and 2-NP are formed in the atmosphere. Of the five nitroarenes, 2-NF had the largest suburban / downtown concentration ratio. 2- and 4-NPs and 6-NC all showed larger ratios than did 1-NP. These results showed that 2-NF and 2-NP were formed in the atmosphere, but that the secondary formation of 4-NP and 6-NC were not known. Taking mutagenic activity and the atmospheric concentration into consideration, the mutagenic contribution of 2-NF was estimated to be comparable with that of 1-NP in the downtown area, and more than that of 1-NP in the suburban area. This result suggested that the mutagenic contribution of the minor nitroarenes formed in urban air might not be negligible.

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The effect of soybean saponin on bone components in the femoral tissues of rats was investigated. Rats were orally administered saponin (100μg/ml/100g body weight) for 10 d. The administration caused a significant increase in calcium content, alkaline phosphatase activity, and deoxyribonucleic acid (DNA) content in the diaphyseal and metaphyseal tissues of the femur in the animals. When bone tissues were cultured for 24h in a medium containing either vehicle or saponin (10μg/ml of medium), the presence of saponin caused a significant rise in calcium content, alkaline phosphatase activity, and DNA content in the femoral-diaphyseal and metaphyseal tissues. The effect of saponin in increasing bone components was completely prevented by the presence of cycloheximide (10^-6M), suggesting that the saponin effect is partly based on a newly synthesized protein component. This study demonstrates that soybean saponin has an anabolic effect on bone components in rats, suggesting its role as a nutritional factor in the prevention of osteoporosis.

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Organic halogens (OX) extractable with a water-miscible organic solvent in samples from municipal solid waste incinerators (MSWIs) were determined quantitatively using apparatus for measuring total organic halogens in drinking water. Besides OX, polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in samples from MSWI were analyzed separately to compare their behavior in MSWI. OX was generated both in flue gas and the electrostatic precipitator and exhibited a linear correlation with both PCDD and PCDF, implying that PCDD and PCDF were derived from OX. These results show that OX is a useful surrogate marker for PCDD and PCDF in MSWIs.

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The estrogenic effect of fenthion, an insecticide, in goldfish (Carassius auratus) was examined in terms of the induction of vitellogenin, a biomarker of estrogens in fish. When male goldfish were kept in water containing diethylstilbestrol (0.1mg/l) or nonylphenol (0.5mg/l) for 5 days, a significant level of vitellogenin in the blood was observed. However, vitellogenin was not detected in the blood of male goldfish kept in water containing fenthion (3mg/l) for 5 days. When female goldfish were kept in water containing fenthion for 5 days, the levels of vitellogenin in the blood were not enhanced . Furthermore, fenthion sulfoxide and fenthion sulfone, the oxidized products of fenthion, did not induce vitellogenin in male goldfish. These results suggest that fenthion and its oxidized products do not produce estrogenic activity in goldfish.

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The in vitro metabolism of fenthion, an insecticide, was examined in fish, focusing on the interconversion between fenthion and its sulfoxide (fenthion sulfoxide). When fenthion was incubated with hepatopancreas microsomes of goldfish, Carassius auratus, in the presence of NADPH, the oxidized metabolite, fenthion sulfoxide was formed, but not fenthion sulfone. The oxidase activity was inhibited by SKF 525-A, and partly by α-naphthylthiourea. In contrast, fenthion sulfoxide was reduced back to fenthion by the hepatopancreas cytosol of goldfish in the presence of 2-hydroxypyrimidine, an electron donor for aldehyde oxidase. The activity was markedly inhibited by menadione, an inhibitor for aldehyde oxidase. The interconversion appears to be mediated mainly by the cytochrome P450 system and aldehyde oxidase.

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In the pharmacotherapy of patients receiving hemodialysis, the possible exclusion of an administered drug by hemodialysis should be recognized. The present study was undertaken to predict dialyzability of a drug during hemodialysis using an in vitro dialysis system with three different dialyzers made from high performance membrane. Levofloxacin having relatively low binding-affinity to plasma protein was removed ideally during in vitro dialysis. Amlodipine was also eliminated from the blood, although it is generally believed that such drugs with high binding affinity to plasma protein are removed less efficiently. Examination of the adsorption rate and clearance of the drug revealed that disappearance of amlodipine was due to its adsorption to dialysis membrane and its circuit. Thus, drugs with high protein binding-affinity may possibly be removed by dialyzers with high performance membrane.

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Previously we reported the mutagenicity of drinking water using Salmonella typhimurium TA100 and TA98 with and without S9 mix, and suggested that mutagens might be produced by the chlorination process. It is quite important to determine factors present in our environment affecting the mutagenicity of drinking water. Therefore, as a further study, modifiers of the mutagenicity of drinking water were investigated including dismutagens in order to invent means of the prevention of producing mutagens in drinking water. The mutagenicity of drinking water decreased as the treatment temperature of drinking water samples increased. Freezing and melting treatment of drinking water did not affect the mutagenicity of these samples. The UV irradiations of the samples reduced mutagenicity levels significantly. On the other hand the sunlight did not affect the mutagenicity of drinking water. The mutagenicity of drinking water samples decreased when the samples were treated by reducing agents such as ascorbic acid and glutathion. Especially, glutathion contained in most human tissues, reduced the mutagenicity of drinking water with 100%. It was suggested that the mutagenic compounds in drinking water are electrophilic and the conjugation of electrophiles with glutathion may represent a dismutagenic mechanism.

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Rapid identification and quantification of pesticides in biological samples in cases of poisoning are very important in improving the survival rate in such cases. We previously investigated the effectiveness of a screening and quantification method for fat-soluble pesticides by HPLC equipped with a photo-diode-array detector (HPLC-DAD). In the present study, we investigated a more rapid method of screening and quantitative analysis of 10 important fat-soluble pesticides (propanil(DCPA), fenobucarb(BPMC), pyridaphenthion, napropamide, isoprothiolane, malathion, fenitrothion (MEP), edifenfos(EDDP), diazinon, and isoxathion) employing column-switching HPLC-DAD together with a direct injection method of biological samples. The detection limits of the 10 pesticides were less than 10ng per injection, except for isoxathion in artificial gastric juice and urine. Linear calibration curves for the 10 fat-soluble pesticides in artificial gastric juice were in the range of 1-250μg/ml, and in serum and urine were in the range of 0.1-50μg/ml (except for isoxathion in urine). The recovery rates of all pesticides were greater than 80%, except for fenitrothion and diazinon in artificial gastric juice, edifenfos in serum, and diazinon and isoxathion in urine. This method was applied to three actual cases of acute poisoning, and we were able to provide important information to doctors on the basis of the rapid method of screening and quantitative analysis of pesticides in biological samples. The direct injection method in this paper could shorten analyzing time by 1-1.5h compared to the previous method that necessitating solvent extraction prior to HPLC analysis.

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Three effective ingredients, dl-α-tocopheryl acetate (TA), dipotassium glycyrrhizinate (PG) and β-glycyrrhetinic acid (GA) in aerosol hair growers were determined using a complete closed sampling system connected to a liquid chromatograph. The aerosol solution in the sample aerosol was induced into a six-way valve and then into a drain valve by a Teflon tube. The sample aerosol and the six-way valve were immersed in a water bath at 3±0.3°C. After regulating the drain valve to prevent emerging bubbles from the Teflon tube, the six-way valve was switched, and the aerosol solution in the 7.30μl of loop on the six-way valve was led to the liquid chromatograph. The standard solution containing effective ingredients instead of the sample aerosol solution was injected with a 5ml syringe. A photo-diode array detector was used for qualitative and quantitative liquid chromatographic analysis. By this method, errors originated from the determination could be completely eliminated. These errors arose from the air-borne loss of nebulized sample and the lower weight estimation of the sample solution caused by dissolving propellant, and they were often detected in the sampling procedure of aerosol solution in the conventional way. This method enabled us a constant quantitative sampling by inducing the aerosol solution into the quantitative loop as a liquid . And also by this method the unit of analytical results could be obtained as weight per volume percentage, not as weight per weight percentage of that values which might vary due to the specific gravity of the liquefied propellant or volatile solvents vaporized after the use of aerosol. The recoveries of TA, PG, GA added to commercial aerosol hair growers were 93.3-101.0%. The analytical results of seven commercial aerosol hair growers were 0.02-0.06% (w/v) for TA, 0.04-0.08% (w/v) for PG and 0.02-0.08% (w/v)for GA.

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A method for determinations of sennoside A (SA) and sennoside B (SB) included in "health tea" by capillary electrophoresis (CE) was developed. A 0.02M sodium borate solution adjusted to pH 10.8 was used for the running buffer. SA and SB were detected at UV 260nm. C. V. (%) of migration times for SA and SB were 0.07 and 0.06%, and that of the peak area was 1.3%. The detection limits of SA and SB were 2ppm. As CE has high theoretical plates, the refinement of sample was simplified and the time for analyzing extracts was shortened to about 1/3 of that by HPLC. Six samples of "health tea, " advertised with a likely effect of losing weight, were examined and SA and SB were detected from three of the samples. The total concentrations of SA and SB were 0.11-0.28%.

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