• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
• /
• pp.310-312
• /
• 1999

• Toxicological Research
• /
• 제14권3호
• /
• pp.321-328
• /
• 1998

This study was performed to evaluate the effect of liver damage on toluene metabolism in rats pretreated with carbon tetachloride. Liver damage in rats was induced by administration of 0.1ml of carbon tetrachloride per 100g of body wight intraperitoneally every day for four weeks except the last day before sacrifice. One day before sacrifice, toluene was administered to the animals instead of carbon tetrachloride. Rats were sacrificed at the 1st, the 2nd, the 3rd and the 4th week after the first administration of carbon tetachloride. Based on the histopathological findings, liver weight and serum alanine aminotransferase, the $CCl_4$-preteated group was found to have gradual severe liver damage. Especially the degree of liver injury became increasingly severe throughout the whole course of the experiment. The contnts of hippuric acid in urine lower in the all groups pretreated with $CCl_4$than that of the control. The contents of hepatic cytochrome P450(CYP), benzylalcohol dehydrogenase and benzaldehyde dehydrogenase activities were decreased in $CCl_4$-pretreated rats than those of the control. The $CCl_4$treated animals showed the gradual decreased activities of these enzyme as injection times elapsed. Km values of the benzylalcohol dehydrogenase in pooled liver samples from $CCl_4$-pretreated or control groups were similar. On the other hand, Vmax values of the $CCl_4$-pretreated group was lower than of the control. Therefore, it can be concluded that reduction of the toluene metabolism in damaged rat liver induced with $CCl_4$was due to the inhibition of CYP content, bezylalcohol and benzaldehyde dehydrogenase activities which related with toluene metabolic enzyme system.

• 한국산업보건학회지
• /
• 제21권1호
• /
• pp.49-54
• /
• 2011

In order to develop the methods for exposure assessment and find susceptibility markers for the workers who are exposed to low doses of toluene, xylene and other chemical in petroleum industries, we investigated the application of P-450 expression in human lymphocytes utilizing mouse monoclonal anti-rat CYP2B1/2, the levels of toluene and xylene in air and their metabolite levels in urine with the levels of expressed CYP2B1/2 proteins. The general characteristics such as age, smoking and drinking habit were no significant difference between the control and exposed workers, but the working durations and working hours were significantly different. Workers in exposed group were exposed to the mean of 2.1 ppm (range, 0.00-4.54) of toluene and 0.3 ppm (rang, 0.00-1.23) of xylene. The mean concentration of urinary hippuric acid was low and less than 1/5 of the biological exposure index recommended by the Ministry of Employment and Labor Korea. Methyl hippuric acid in urine was not detected in control and exposed workers. Also, there were no significant differences in the levels of the urinary metabolites between the control and exposed group. When chemiluminescence dot blottings were carried out utilizing mouse monoclonal antibody against CYP2B1/2, the strong density dots corresponding to a mouse monoclonal antibody was observed in the human lymphocytes from the exposed workers. These results suggested that the chemiluminescence dot blot assay for CYP of lymphocytes should be valuable for identifying CYP expression as biomarkers in the workers exposed to toluene and xylene.

• Journal of Preventive Medicine and Public Health
• /
• 제25권2호
• /
• pp.157-161
• /
• 1992

톨루엔의 폭로가 인체의 면역기능에 미치는 영향에 대해 알아 보기 위하여 톨루엔 취급자 21명과 일반 사무직 근로자 12명에 대하여 혈액 및 말초혈액 림프구의 subpopulation에 대하여 조사하였다. 혈액소견은 두 군 모두 정상범위로 통계적으로 유의한 차이가 없었다. CD4 림프구 세포의 비율은 두 군에서 유사하였으며 T와 B림프구 및 CD8 림프구 세포의 비율은 폭로군에서 약간 낮았으나, 두 군 모두 정상 범위로 통계적으로 유의한 차이가 없었다. 폭로군에서 T 림프구 및 CD4 세포의 비율은 근무기간이 길수록 통계적으로 유의하게 증가하였다(P<0.05). 본 연구의 폭로군에서 림프구의 subpopulation은 전반적으로 비폭로군보다 약간 낮은 경향은 있었지만, 정상범위에 해당하였으므로 톨루엔에 폭로되었을 때 인체에 대한 면역기능은 큰 영향이 없는 것으로 생각되어진다. 그러나 폭로기간에 따라 면역기능이 변동하는 것으로 보아 톨루엔이 인체의 면역기능에 미치는 영향에 관한 지속적인 연구가 이루어져야 하겠다.

• Archives of Pharmacal Research
• /
• 제17권2호
• /
• pp.66-70
• /
• 1994

The condensation reactions of hippuric acid and tis furyl derivative with salicyladehydes or that of salicylhippuric acid analogues with furadehyde led to the comesponding oxazoles. These wre subsequently treated with hydrazine hydrate, hydroxylamine or subjected to alkaline hydrolysis to yield new o-hydroxyaryl or salicyl containing derivatives. 5-Substituted salicylanilides were treated with piperidine and formaldehyde in a Mannich type reaction affording the corresponding 3-(N-piperidinomethyl) salicylanilides. It was noticed that the presence of an electron donating group in in position 3 in the salicylanilide moiety decrease the mollusicidal activity.

• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1997년도 추계 학술대회 연제집
• /
• pp.210-211
• /
• 1997

• Safety and Health at Work
• /
• 제2권3호
• /
• pp.229-235
• /
• 2011

Objectives: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a $31^{st}$ round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. Methods: One hundred and eighteen laboratories participated in the $31^{st}$ round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. Results: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. Conclusion: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.

• Asian-Australasian Journal of Animal Sciences
• /
• 제10권3호
• /
• pp.260-264
• /
• 1997

This study was conducted with adult cockerels to determine whether dietary RNA affects feed intake and renal weight and function, and if the responses are similar to dietary adenine. Chickens were ad libitum fed a RNA diet (100 g/kg) or an adenine diet (9.1 g/kg) for 14 d and catheterized in right jugular vein, hepatic portal vein and both urethers, and saline together with para-amino hippuric acid and sodium thiosulfate was continuously infused into them to evaluate renal functions. Dietary RNA reduced feed intake and body weight, and dietary adenine increased kidney weight expressed as a proportion of body weight (P < 0.05). Feed intake and body weight on the adenine diet and kidney weight on the RNA diet showed similar though non significant tendencies. No calculi were detected in the kidney in chickens fed either the RNA or adenine diets. Plasma inorganic phosphate (IP), Ca and 1,25 $(OH)_2$ vitamin $D_3$ concentrations were increased by dietary RNA and adenine, although the increases of IP and Ca in adenine-fed chickens were not significant. Uric acid and urea concentrations in the blood plasma were unaffected by dietary RNA or adenine. Both dietary RNA and adenine increased renal blood flow rates 3.5-3.7 fold, renal plasma flow rates 3.4-3.7 fold and glomerular filtration rates (GFR) 2.9-3.0 fold (p < 0.01). Clearance of urea, IP and Ca were also enhanced by dietary RNA, but not by dietary adenine. However, neither RNA nor adenine affected uric acid clearance. Only IP clearance was significantly augmented at the glomerular level by dietary RNA (p < 0.05). Glomerular filtration of uric acid, urea, IP and Ca and reabsorption of urea, IP and Ca at the renal tubule were increased by dietary RNA and adenine (p < 0.05), whereas tubular secretion of uric acid was decreased by both dietary treatments. It is concluded that dietary adenine is effective in changing renal function and P and Ca metabolism in chickens.

• 한국산업보건학회지
• /
• 제19권1호
• /
• pp.73-79
• /
• 2009

This study was undertaken to investigate the effects of single and combined exposure of toluene (T) and xylene (X) on the cytochrome-450(CYP)-mediated metabolizing capacity, induction of CYP isozymes and the excretion of their metabolites in urine. Animal were adults male Sprague-Dawley (SD) rats and divided into 4 groups such as control, T (treated with 63.7 mg/body kg), X (treated with 65.9 mg/body kg) and TX(T=X). Organic solvents was administrated by intraperitoneal injection for 3 days. The contents of protein and CYP in liver microsomes of control group were $16.48{\pm}0.56 mg/m{\ell}$ and $0.744{\pm}0.025$ nmol/mg protein, respectively, and they contents were significantly lower than in derived from treated groups (p<0.01). The activities of PROD and ${\rho}NPH$ were significantly higher in single treated groups than in control and combined group (TX). When Western immunoblotting were carried out with two monoclonal antibodies (MAb 1-98-1 and MAb 2-66-3) which were specific against CYP2B1/2 and CYP2E1, respectively, a strong signal corresponding to CYP2B1/2 was observed in microsomes obtained from rats treated with X and TX. The color density against CYP2E1 was slightly increased in T and TX groups compared with C and X groups. The amounts of urinary hippuric acid in T single treated group was $3.29{\pm}1.97$ g/g creatinine and TX combined group was $2.91{\pm}1.76$ g/g creatinine, but was not significant. However, amount of urinary methy hippuric acid in X single treated group ($1.62{\pm}0.72$ g/g creatinine) was significantly higher than TX combined group ($0.93{\pm} 0.63$ g/g creatinine)(p<0.01). These results suggested that CYP2E1 isozyme might be responsible for the metabolism of T, and CYP2B1/2 isozyme is for X. And also, difference of metabolites level between single and combined group may be speculated that the intermediates of T and X interacted each other in the process of their metabolite formation reaction.

• 한국산업보건학회지
• /
• 제8권2호
• /
• pp.296-305
• /
• 1998

흰쥐에 있어서 toluene 또는 ethanol 전처치가 toluene 대사에 어떠한 영향을 미치는지를 검토하는 일환으로 흰쥐에 toluene 또는 ethanol을 경시별로 4주간 투여한 다음, 톨루엔을 1회 재투여한 후 처치하여 다음과 같은 결과를 얻었다. 즉, 간조직의 광학 및 전자현미경을 통한 병리조직학적 소견과 체중당 간무게, 혈청 alanine aminotransferase 활성 및 간조직 중 glutathione 함량 변동을 관찰한 결과, toluene 및 ethanol 전처치군 모두 가역적 간손상 정도가 관찰되었으며 톨루엔 및 에탄올 전처치군 간에 간손상 정도 차이는 볼 수 없었다. 이러한 실험동물 모델에서 toluene 및 ethanol 전처치군 모두 요 중 마뇨산 농도가 대조군 보다 높게 나타났으며 toluene 대사에 관여하는 간조직의 cytochrome P-450 함량 및 benzylacohol(BAD) 또는 benzaldehyde dehydrogenase(BzAD) 활성치가 대조군 보다 높게 나타났다. 그리고 요 중 마뇨산 농도와 BAD 및 BzAD 의 활성치는 톨루엔 전처치군이 에탄올 전처치군 보다 전 실험기간 동안 대체로 다소 높게 나타났다. 또한 간조직의 benzylalcohol dehydrogenase의 반응속도를 관찰한 결과 $V_{max}$치는 toluene 및 alcohol 전처치군 모두 대조군 보다 높게 나타났다. 이상 실험결과를 종합해 볼 때 실험동물에 toluene 및 ethanol 전처치가 toluene 대사를 촉진시키며 이는 toluene 대사에 관여하는 효소활성에 영향을 미쳐 나타난 결과로 생각된다.