• Title/Summary/Keyword: Subchronic

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A Study on the Development of a Health Risk Assessment Method for the Management of the Health Environment of Residents Living Around Areas Affected by Chemical Accidents (화학사고 주변 지역 거주자의 보건환경 관리를 위한 건강위해성 평가 방법 개발에 관한 연구)

  • Park, Sihyun;Park, Sejung;Park, Taehyun;Yoon, Danki;Jung, Jonghyeon;Gang, Sungkyu;Lee, Dongsoo;Seo, Youngrok;An, Yeonsoon;Lee, Cheolmin
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.28 no.1
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    • pp.1-17
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    • 2018
  • Objectives: This research is part of a study to be conducted over five years starting from 2017 by the Ministry of Environment on the development of technologies to evaluate the impact of chemical accidents on the human body. Methods: For this research, a five-stage specific study method was developed. Results: In brief, the developed health risk assessment method can be summarized as follows. First, a health risk assessment system was built based on the guidelines set forth by the USA NRC/NAS. Second, based on the disease manifestation theory, the health risk assessment method was divided into 1) a carcinogenic health risk assessment method focused on all carcinogens except non-genotoxic carcinogens and 2) a non-carcinogenic health risk assessment method focused on noncarcinogens including non-genotoxic carcinogens. Third, the detailed contents of the health risk assessment method were developed in four stages(hazard identification, dose-response assessment, exposure assessment, and risk determination) through theoretical consideration of the assessment of the level of health risk related to chemical exposure. Finally, a health risk assessment methodology, classified into stages to address acute, subacute/subchronic, and chronic conditions was developed after considering the physicochemical behavior of hazardous chemicals upon implementation of countermeasures after a chemical accident. Conclusions: A method to evaluate the health risks related to toxic chemicals generated by chemical accidents was developed. This study was performed with the purpose of developing a mathematical health risk assessment method to evaluate the health effects of exposure to hazardous chemicals upon implementation of emergency countermeasures after chemical accidents.

Changes of Pulmonary Function and Biopersistence Evaluation of Sepiolite in Sprague-Dawely Rats (랫드에 주입된 세피오라이트에 의한 폐기능 변화 및 생체내구성 평가)

  • Chung, Yong Hyun;Han, Jeong Hee;Sung, Jae Hyuck;Yu, Il Je
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.16 no.4
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    • pp.303-313
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    • 2006
  • Two kinds of sepiolite (sepiolite 1, sepiolite 2), a $500^{\circ}C$ heat treated sepiolite (sepiolite 500), and a $700^{\circ}C$ heat treated sepiolite (sepiolite 700) were analyzed for their physicochemical properties. After these sepiolites were instilled into rat lungs, the effects of these substances on lung function and biochemical changes were evaluated. In addition, the fibers in the lungs were counted and characterized after the lungs were treated for electron microscopical analysis. The lungs instilled with sepiolites increased their weight and tidal volume statistically significantly compared with the unexposed control. The numbers of lymphocytes and polymorphonuclear cells (PMN) in the bronchoalveolar lavage (BAL) fluid also increased compared with the control, indicating the sepiolite induced inflammation. The heat treated sepiolites, however, did not show any toxicological differences from the untreated sepiolites. Although sepiolite showed less change in fiber atomic % compositions ( sepiolite 500, Si 0.9%, p <0.01 ; sepiolite 700, Si 3.7%, p<0.05) than chrysotile (Si 9.7%, p<0.01), the durability of the fibers in the lungs could not be determined in this subchronic experiment.

Anti-Inflammatory Activity of Elsholtzia splendens

  • Kim, Dong-Wook;Son, Kun-Ho;Chang, Hyeun-Wook;Bae, Ki-Hwan;Kang, Sam-Sik;Kim, Hyun-Pyo
    • Archives of Pharmacal Research
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    • v.26 no.3
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    • pp.232-236
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    • 2003
  • Elsholtzia splendens Nakai has been used in North-East Asia as an ingredient of folk medicines for treating cough, headache and inflammation. The present investigation was carried out to establish its in vivo anti-inflammatory activity using several animal models of inflammation and pain. The 75% ethanol extract of the aerial part of E. splendens significantly inhibited mouse croton oil-induced, as well as arachidonic acid-induced, ear edema by oral administration (44.6% inhibition of croton oil-induced edema at 400 mg/kg). This plant material also showed significant inhibitory activity against the mouse ear edema induced by multiple treatment of phorbol ester for 3 days, which is an animal model of subchronic inflammation. In addition, E. splendens exhibited significant analgesic activity against mouse acetic acid-induced writhing (50% inhibition at 400 mg/kg), while indomethacin (5 mg/kg) demonstrated 95% inhibition. E. splendens ($5-100{\;}{\mu}g/mL$) significantly inhibited $PGE_2$ production by pre-induced cyclooxygenase-2 of lipopolysaccharide-treated RAW 264.7 cells, suggesting that cyclooxygenase-2 inhibition might be one of the cellular mechanisms of anti-inflammation.

Study on Subchronic Inhalation Toxicity of 1, 1-dichloro-1-fluoroethane using S.D. Rats (S.D. Rats를 1, 1-Dichloro-1-fluoroethane의 아만성 흡입독성 연구)

  • 김현영;이성배;임철홍;김철우;정용현;한정희;전윤석;최수영;강대봉
    • Environmental Analysis Health and Toxicology
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    • v.17 no.1
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    • pp.81-93
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    • 2002
  • There were no specific effects for test materials on Sprague-Dawiey (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body 1, 1-Dichloro-1-fluoroethane (used as coolant, metal cleaner and solvents) exposure (0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations. there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration . Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-1-fluoroethane inhalation was evaluated in groups with 3,000 ppm below (S.D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-1-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure.

A Proposal of Dietary Supplement from Choto-san, a Kampo Medicine

  • Watanabe, Hiroshi
    • Biomolecules & Therapeutics
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    • v.12 no.3
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    • pp.138-144
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    • 2004
  • Therapeutic effect of a Kampo medicine, Choto-san, in patients with vascular dementia was demonstrated by a double-blind and placebo-controlled clinical trial. To clarify the therapeutic efficacy of Choto-san, anti-ischemic effect in mice, hypotensive effect in spontaneously hypertensive rats (SHR), anti-oxidative effects in vitro, and N-methyl-D-aspartate (NMDA) receptor-blocking activity using Xenopus oocytes were studied. (1) Pretreatment with Choto-san (0.75-6.O g/kg, P.O.) or a component herb Chotoko (Uncaria genus: 75 - 600 mg/kg, P.O.) prevented ischemia-induced impairment of spatial learning behaviour in mice. Indole alkaloids- and phenolic fractions extracted from Chotoko also improved significantly the learning deficit. (2) Subchronic administration of Choto-san (0.5 g/kg, p.o.) caused a significant hypotensive effects in SHR. (3) Choto-san, Chotoko, and the phenolic constituent, (-) epicatechin, significantly protected the NG108-15 cell injury induced by $H_20_2$ exposure in vitro and also inhibited lipid peroxidation in the brain homogenate. (4) Indole alkaloids, rhynchophylline and isorhynchophylline (1-100 uM), reversibly reduced NMDA-induced current in the receptor-expressed Xenopus oocytes. These results suggest that anti-vascular dementia effects of Choto-san are mainly due to the effect of Chotoko. From these results, it is possible to make a novel dietary supplement through several extraction steps from Chotoko.

Keum-Ryung-Ja-San, an Traditional Herbal Prescription, Ameliorates Depressive Behaviors in Mice

  • Jung Ji-Wook;Lee Seung-Joo;Yoon Byung-Hoon;Kim Dong-Hyun;Ryu Jong-Hoon
    • Biomolecules & Therapeutics
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    • v.14 no.2
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    • pp.114-118
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    • 2006
  • Depression is a very difficult disease to be cured because several nervous systems are involved. In the present study, we evaluated the effects of Keum-Ryung-Ja-San (KRJS), a traditional herbal prescription, on depressive behaviors in mice using the forced swimming test. KRJS was given 1 h prior to the forced swimming test (50, 100, 200, an400 mg/kg, p.o.). The duration of immobility time in the forced swimming test was significantly reduced by KRJS treatment (200 mg/kg, P<0.05) and similar effects were observed with a classical antidepressant, imipramine (15 mg/kg, i.p.). With subchronic administrations of KRJS and its constituents at several doses for 1 week, a decreased duration of immobility time was observed with KRJS and Corydalis ternata (200 mg/kg, p.o. P<0.05). These results suggest that KRJS may have antidedpressive activities and CT may contribute to the antidepressive activity of KRJS.

Effect of Solanum lyratum Extract on the Hepatotoxicity of Carbon Tetrachloride in Rats (백모등 엑스의 간기능개선 효과)

  • Yang, Jae-Heon;Choi, Cheol-Ung;Kim, Dae-Keun;Lee, Kang-Ro;Zee, Ok-Pyo
    • Korean Journal of Pharmacognosy
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    • v.27 no.3
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    • pp.167-172
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    • 1996
  • The studies were attempted to investigate the therapeutic effect of Solanum lyratum extract(SLE) on the liver damage induced by carbon tetrachloride in rats. Male rats (Sprangue-Dawley) were treated with subchronic concentration of $CCl_4$, which was 1 mg/kg of $CCl_4$ via per oral administration daily for three days. The level of serum cholesterol, transaminase, bilirubin and BSP were measured. Treatment of SLE significantly decreased the increment in serum transaminase activities, total cholesterol and enlargement of liver but serum bilirubin was not reduced. The protective effect was observed when SLE was given daily for 4 weeks after $CCl_4$ treated for 3 days. SLE administration to rats prevented the development of fatty change, necrosis, and fibrosis induced by $CCl_4$. The results suggest that SLE has appreciable therapeutic effect on $CCl_4$ induced hepatotoxicity.

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Subacute Toxicity Test of Guh Sung Y.L.S.-95 (Guh Sung Y.L.S.-95의 아급성 독성시험)

  • 김판기;왕성호;김대용
    • Journal of Food Hygiene and Safety
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    • v.12 no.3
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    • pp.234-239
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    • 1997
  • Guh Sung Y.L.S.-95 is one of the polyacidic solution of which main component is acetic acid. We investigated the subchronic toxicity of the Guh Sung Y.L.S.-95 using SPF ICR mouse for 4 weeks. The Guh Sung Y.L.S.-95 was administered by gastric intubation, 1.0, 2.5, 5.0 g/kg body weight. The results are as follows: 1. There are no adverse effects on the clinical obserbation and body weight changes. Also, there are some significant changes in organ weight, but it was meaningless because of the absence of dose-response relationships. 2. In the hematological patterns of administered mouse, there are no significant changes between the treated groups. Also, there are no serological enzymatic changes in the treated mouse. In the 1.0 g/kg treated group, ASP activity was increased significnatly compared with control group. But, this level of activity was fall under the normal physiological range of control mouse. 3. Histopathological findings of the brain, liver, heart, spleen, kidneys, stomach, lung, testis, ovary, uterus and thymus were not observed in the treated mouse. From the above results, the Guh Sung Y.L.S.-95 has no toxicity upto the 5.0 g/kg/day of oral dose for 4 weeks.

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Study for Thirteen Weeks Subacute Toxicity of BDR-29 in Rats (BDR-29의 랫트에 대한 13주 반복투여 독성에 관한 연구)

  • Chang, Bo-Yoon;Kang, Dae-Gill;Lee, Ho-Sub;Kim, Sung-Yeon
    • Korean Journal of Pharmacognosy
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    • v.39 no.1
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    • pp.60-67
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    • 2008
  • The subcronic toxicity of BDR-29, a herbal preparation of Cassiae Semen, Prunellae Spica, Tribuli Fructus, and Uncariae Rhamulus et Uncus, was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance at a dose 5 mg/kg, 50 mg/kg and 500 mg/kg intragastrically for 13 weeks. No death and abnormal clinical signs were observed throughout the administration period. There were not significantly different from control group in net body weight gain, food and water consumption, organ weight, gross pathological findings, and urine analysis among the groups rats treated with different doses of the BDR-29. Hematological findings and biochemical examination revealed no evidence of specific toxicity related to BDR-29. From these results, no observation effect level (NOEL) of BDR-29 is 500 mg/kg/day under the condition employed in this study.

Subchronic Oral Dose Toxicity Study of Enterococcus Faecalis 2001 (EF 2001) in Mice

  • Gu, Yeun-Hwa;Yamasita, Takenori;Kang, Ki-Mun
    • Toxicological Research
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    • v.34 no.1
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    • pp.55-63
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    • 2018
  • As a part of general toxicity studies of Enterococcus Faecalis 2001 (EF 2001) prepared using heat-treatment bacillus mort body EF 2001 in mice, this study examined the toxicity of EF 2001 in single and repeated administrations following the previous report in order to apply this product to preventive medicine. The safety of oral ingestion of EF 2001 was examined in 6-week-old male and female ICR mice with 1,000 mg/kg, 3,000 mg/kg and 5,000 mg/kg body weight/day administrated by gavage of the maximum acceptable dose of EF 2001. The study was conducted using distilled water as a control following the methods for general toxicity studies described in the "Guidelines for Non-clinical Studies of Pharmaceutical Products 2002". As a control, 1) observation of general conditions, 2) measurement of body weight, 3) determination of food consumption, 4) determination of water consumption, 5) blood test and urinalysis and 6) pathological examination were performed for the administration of EF 2001. Mice received EF 2001 for 13 weeks and results were compared with those of the control group that received distilled water. The results of the above examinations revealed no significant differences between control and EF 2001 groups for both males and females. Thus, no notable toxicity was confirmed with single and repeated oral administrations of EF 2001. Oral administration in the above doses did not result in abnormal symptoms or death during the observation period. No abnormalities in blood cell count or organ weights were seen. Without any evidence of toxicity to cells and organs, EF 2001 is speculated to not adversely affect living organisms. The 50% lethal dose of EF 2001 with oral administration in mice is estimated to be greater than 5,000 mg/kg body weight/day for both male and female mice. Therefore, $LD_{50}$ value for animals was 5,000 mg/kg or more.