• Fisheries and Aquatic Sciences
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• 제9권1호
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• pp.38-43
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• 2006

We developed and evaluated a method of short-term acute toxicity testing based on the feeding behavior of Ceriodaphnia dubia. In prior toxicity tests, neonates of C. dubia were hatched and cultivated with the addition of yeast only for the preparation of the transparent daphnid's gut. Scenedesmus subspicatus was supplied as food after 1 to 6 h of exposure to toxicants. The effects of 1-h and 6-h exposure time on test sensitivity did not significantly differ. A comparison of the short-term l-h acute toxicity test developed in this study to the standard 48-h acute toxicity test using heavy metals, cyanide, and pentachlorophenol indicated that the 1-h test provided an acceptable sensitivity level in toxicity testing of C. dubia..

• 대한한의학회지
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• 제21권3호
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• pp.199-208
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• 2000

Objectives : In order to investigate the toxicity of rats after oral administration of Eumcheonyijin-tang extract. Methods : The experimental animals were subdivided into control, short term administration group, and long term administration group. With changes of gross appearance, the histological changes of liver and kidney were observed. Blood chemical indexes used in this study were AST, ALT, total bilirubin, albumin, BUN and creatinine in serum. Results : In the long term administration group, histological changes were detected in the liver as centrolobular disposition of fatty tissue(adipose cell), and in serum test, AST, ALT increased at 21 days after administration group, serum total bilirubin were increased 21, 28 and 35 days after administration group. So it seems to induce toxicity. Kidneys of the long term administration group revealed histological changes : increasing of connective tissue and pyknosis of glomerulus cell were observed at 28 days after administration group, and in serum test, significant changes of albumin, BUN, and creatinine were admitted. So it seems to induce toxicity. Conclusions : In long term administration of Eumcheonyijin-tang toxicity was induced.

• Environmental Analysis Health and Toxicology
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• 제24권4호
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• pp.311-320
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• 2009

The short term (24-hr) and long term (21 days) effects of copper, cadmium, fenbendazole and sulfathiazole on the survival of the Korean fairy shrimp Branchinella kugenumaensis were evaluated. The 24-hr median lethal concentrations ($LC_{50}$) of copper, cadmium, fenbendazole, and sulfathiazole were 39, 512, 182, and 31,818 ${\mu}g/L$, respectively. The toxicity of copper is highest among 4 chemicals used in this study, while sulfathazole the lowest. After the long term (21 days) exposure experiment, the $LC_{50}$ copper, cadmium, fenbendazole, and sulfathiazole were 1.12, 2.1, 0.1, 6.6 ${\mu}g/L$, respectively. The long term effects of antibiotics were highly enhanced while the short-term effects were not strong. The sensitivities of B. kugenumaensis to copper and cadmium were higher than or comparable to those of other freshwater branchiopods (Streptocephalus spp., Thamnocephalus sp.), and far higher than the marine species (Artemia sp.). There were significant effects on the survival of B. kugenumaensis after long term exposure to relatively lower concentrations of copper, cadmium, fenbendazole and sulfathiazole. Therefore, B. kugenumaensis seems quite a good candidate species for the ecotoxicological assessments of freshwater environments.

• 한국축산식품학회지
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• 제23권2호
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• pp.137-144
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• 2003

본 연구에서는 IGFs를 다양한 기능성 유제품에 적용하기 전에 먼저 상업용 IGFs 및 초유로부터 분리.정제된 IGFs의 안전성을 평가하여 새로운 기능성 소재로서의 IGFs의 가능성을 검토해 보고자 하였다. 이를 위하여 독성평가에서 기본적으로 수행되고 있는 단회투여독성시험과 반복투여독성시험을 실시하였다. 단회투여독성시험에서는 R&D Systems사의 Recombinant Human IGF- I 을 시험물질로 하고 생후 4주된 Sprague-Dawley계(♂) 흰쥐(rat)를 실험동물로 하여 개체당 0, 10, 20, 50 $\mu\textrm{g}$씩 투여하는 시험군을 설정한 후, 꼬리정 꼬리정맥에 주사하여 20일간 관찰하면서 체중변화, 식이섭취변화를 측정하고 최종적으로 부검하여 육안검사 및 간장, 신장, 비장에 대한 병리조직검사를 실시한 결과, 명확한 이상소견이 나타나지 않아 모든 시험군에서 급성독성이 확인되지 않았다. 반복투여독성시험에서는 초유로부터 분리.정제된 IGF- I 을 시험물질로 하고 생후 4주된 Sprague-Dawley계(♂) 흰쥐(rat)를 실험동물로 하여 개체당 0, 5, 10, 15 $\mu\textrm{g}$씩 투여하는 시험군을 설정한 후, 14일간 반복적으로 강제경구투여하면서 임상증상을 관찰하면서 체중변화, 식이섭취변화를 측정하였고 최종적으로 부검하여 육안검사 및 간장, 신장, 비장에 대한 병리조직검사를 실시한 결과, 명확한 이상소견이 나타나지 않아 모든 투여농도에서 반복투여독성시험을 비롯한 기본적인 독성평가에 있어서 초유 내 IGF-I의 안전성에는 명확한 이상소견이 없는 것으로 판단되었다.

• 한국수산과학회지
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• 제35권5호
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• pp.534-541
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• 2002

살충제, 살균제 그리고 antifouling 약품 등으로써의 triorganotin의 사용은 지난 30년간 놀라울 정도로 증가해왔다. 이 보고에서는 미세조류 Skeletonema costatum의 성장에 미치는 여러 triorganotin (TBTO, TBTF, CTPT, TBTCI)들의 급성 및 만성 독성효과를 조사하기 위하여, 단기 및 장기 독성실험을 각각 수행하였다. 단기 독성실험에서, 여러 triorganotin들의 S. costatum에 대한 성장저해 효과는 처리농도에 비례하여 증가하였으며, 이 성장저해는 시간 경과에 따라 회복되었다. 그러나 여러 triorganotin의 독성의 성장저해 효과가 접종한 S. costatum의 세포밀도에 따라 다름을 보였다. 접종 세포농도가 높을수록 triorganotin의 독성효과는 감소하였다. 이러한 결과는 triorganotin의 S. costatum에 의한 분해에 의한 것이라고 판단된다. 장기 독성실험에서는 단기 독성실험에서와는 달리 1 $\mu$g/L의 triorganotin의 농도에서도 S. costatum이 사멸하였다. 이러한 사실은 낮은 밀도의 식물성 플랑크톤이 존재하는 해수에서 지속적으로 존재하는 triorganotin의 독성은 훨씬 더 강하게 나타날 수 있음을 보여준다.

• 한국식품과학회지
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• 제31권5호
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• pp.1401-1404
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• 1999

솔잎추출물의 rat에 대한 단기 급성경구독성을 평가하기 위하여 체중 kg당 최고 10g의 솔잎 추출물을 rat의 위에 직접 투입하여 14일간 관찰하였다. 실험 결과 모든 실험군에서 사망예가 관찰되지 않아 $LD_{50}$, 10g/kg B.W. 이상으로 계산되었으며 임상증상이나 체중, 부검에서도 유의할만한 소견이 관찰되지 않았다. 따라서 본 실험의 솔잎 추출물은 rat에 있어서 단기 급성경구독성이나 부작용을 유발하지 않는 소재로 평가되었다.

• 한국환경과학회지
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• 제16권4호
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• pp.425-432
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• 2007

The water flea has been used as a test organism of toxicity test for surface water. Toxicity test with water flea is categorized into two parts. One is acute toxicity test with observing immobility and mortality and the other is chronic toxicity test determined by survival and reproduction of water flea. Heartbeat measurement of water flea was designed as a short-term toxicity test in this study. Direct measurement of heartbeat under microscope by aid of video camera gives and early diagnosis of mortality in short time. Therefore, the effects of measuring illumination, measuring time, and non-feeding during the test on heartbeat of water flea was evaluated to establish a new test approach. Test organisms used in this study are Daphnia magna, a well standardizes toxicity test organism, and Simocephalus mixtus, a newly refined organism $IC_{50}$ values of these test organism by heartbeat measurement were compared and discussed. It was found that toxicity test by heartbeat measurement was a reproducible, easy and simple method accomplished in a few hours.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2002년도 춘계학술대회 논문집
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• pp.21-29
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• 2002

가스계 소화약제시스템의 인명안전 또는 기타 안전관련으로 CO2 시스템과 청정약제시스템을 중심으로 기술해보았습니다. 인명에 대한 위험을 최소화하면서 CO2 소화시스템의 혜택을 얻기 위해서는 설계, 시공, 유지관리면에서의 인명안전에 대해 상당한 관심을 기울여야한다. 청정 소화약제를 통상의 거주구역에 사용할 경우의 주요요소는 독성문제이다. 할로겐화탄소약제 테스트에서의 주요 관점은 급성효과, 즉 단기간 노출의 경우이다. 주요급성효과에는 마취성과 심장감작성이 있다. 불활성가스약제의 경우 주요 신체적 영향으로는 산소농도의 저하문제를 들 수 있다.

• 한국물환경학회지
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• 제20권1호
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• pp.48-54
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• 2004

Two methods, a Ceriodaphnia algal uptake suppression test (CAUST) and a new toxicity test based on temperature control (TTBTC) which are based on feeding behaviour and temperature control, respectively, were developed and compared for the adoption as the better methodology for short-term toxicity screening. As previously published by Lee et aI., (1997), the CAUST method is based on the feeding behaviour of C. dubia and requires as little as 1 hour of contact time between C. dubia neonates and toxicant. However, even though CAUST requires only 1 hour of contact time, this method still take many hours for the preparation and measurement. Before the test starts, neonate digestive tracts were cleared by feeding yeast to the daphnids, Neonates were then exposed to toxicant, followed by addition of Scenedesmus subspiatus into the bioassay vessels. Daphnids were examined under the bright-field microscope with the presence of algae (indicated by a green colored digestive tract) or the absence of algae. Uptake indicated no toxic effect, whereas, absence of uptake indicated toxic inhibition. Unlike CAUST, the newly developed method (TTBTC) is based on just temperature control for the toxicity test of C. dubia. Initially, neonates are exposed to toxicants while the temperature of water bath containing media increased to $35.5^{\circ}C$. After 1.25 hour of contact time, the number of the daphnids, either live (no toxic effect) or dead (toxic effect), is counted without the aid of any instrument. In both methods, median effective concentrations ($EC_{50}$ values) were computed based on the results over a range of dosed toxicant concentrations. It showed that TTBTC was as sensitive as the standard 48-hour acute bioassay and CAUST. TTBTC and CAUST were much more sensitive than the I-hour I.Q. test and 30-minute Microtox. This study indicates that TTBTC is an easier and more rapid toxicity test than the standard 48-hour acute bioassay and even CAUST.

• Toxicological Research
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• 제32권4호
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• pp.289-300
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• 2016

Non-genotoxic carcinogens are substances that induce tumorigenesis by non-mutagenic mechanisms and long term rodent bioassays are required to identify them. Recent studies have shown that transcription profiling can be applied to develop early identifiers for long term phenotypes. In this study, we used rat liver expression profiles from the NTP (National Toxicology Program, Research Triangle Park, USA) DrugMatrix Database to construct a gene classifier that can distinguish between non-genotoxic carcinogens and other chemicals. The model was based on short term exposure assays (3 days) and the training was limited to oxidative stressors, peroxisome proliferators and hormone modulators. Validation of the predictor was performed on independent toxicogenomic data (TG-GATEs, Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System, Osaka, Japan). To build our model we performed Random Forests together with a recursive elimination algorithm (VarSelRF). Gene set enrichment analysis was employed for functional interpretation. A total of 770 microarrays comprising 96 different compounds were analyzed and a predictor of 54 genes was built. Prediction accuracy was 0.85 in the training set, 0.87 in the test set and increased with increasing concentration in the validation set: 0.6 at low dose, 0.7 at medium doses and 0.81 at high doses. Pathway analysis revealed gene prominence of cellular respiration, energy production and lipoprotein metabolism. The biggest target of toxicogenomics is accurately predict the toxicity of unknown drugs. In this analysis, we presented a classifier that can predict non-genotoxic carcinogenicity by using short term exposure assays. In this approach, dose level is critical when evaluating chemicals at early time points.