• Toxicological Research
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• 제32권1호
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• pp.9-14
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• 2016

The National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) provides validation support for US Federal agencies and the US Tox21 interagency consortium, an interagency collaboration that is using high throughput screening (HTS) and other advanced approaches to better understand and predict chemical hazards to humans and the environment. The use of HTS data from assays relevant to the estrogen receptor signaling data pathway is used as an example of how HTS data can be combined with computational modeling to meet the needs of US agencies. As brief summary of US efforts in the areas of biologics testing, acute toxicity, and skin sensitization will also be provided.

• 생약학회지
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• 제40권3호
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• pp.184-189
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• 2009

A simple and reliable reverse phase HPLC method of Coptidis Rhizoma and Salviae Miltiorrhizae Radix were developed to determine pharmacologically active marker compounds. The water-extract of two natural medicines were evaluated by the HPLC methods. The stability test for two extract were examined for five months. However, no significant change in the content of the marker compounds of each extract observed during the time of investigation.

• 한국환경농학회지
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• 제8권2호
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• pp.148-171
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• 1989

• Archives of Pharmacal Research
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• 제22권2호
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• pp.143-150
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• 1999

melatonin (MLT), N-acetyl-5-methoxytryptamine, is mainly secreted by the pineal gland. The ultraviolet (UV), infrared (IR) and 1H-NMR spectra of irradiated and non-irradiated MLT were measured, and phototoxicity tests of MLT, anthracence (positive control) and sodium lauryl sulfate (SLS, negative control) were performed. The methods employed include both in vitro test such as MTS assay using the human fibroblast cell and yeast growth inhibition assay using Candida albicans and in vivo method using the skin of guinea pig. UV absorption spectra and 1H-NMR spectra of MLT were changed by UVA (365 nm, 15 J/$\textrm{cm}^2$), but IR spectra of MLT were not changed. The fifty percent inhibitory concentration (IC50) ratio (UV-/UV+) of MLT was 10. The inhibition zone of irradiated-paper disks treated with MLT was not observed. According to the results of histophathological examination, no pathologic lesion was observed in the non-irradiated group, but slight degeneration of keratinocytes in the epidermis, homorrhage and vasodilation in dermis were observed in the irradiated group. These results indicated that the molecular structure of MLT is altered by UVA to unidentified photoproducts and a moderate phototoxicity of MLT is predicted.

• 생약학회지
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• 제39권3호
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• pp.241-245
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• 2008

Quantitative methods for the marker compounds of Cimicifugae Rhizoma, Achyranthis Radix, Artemisiae Capillaris Herba, Moutan Cortex Radicis and Arecae Semen, respectively, were developed using HPLC-DAD. Using the established methods, each extract of the natural medicines were evaluated. In addition, long term and accelerated stability test in the extracts were examined for six months. No significant change in content of the marker compounds of each extract observed during the time of investigation.

• Toxicological Research
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• 제33권2호
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• pp.107-118
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• 2017

Although alternative test methods based on the 3Rs (Replacement, Reduction, Refinement) are being developed to replace animal testing in reproductive and developmental toxicology, they are still in an early stage. Consequently, we aimed to develop alternative test methods in male animals using mouse spermatogonial stem cells (mSSCs). Here, we modified the OECD TG 489 and optimized the in vitro comet assay in our previous study. This study aimed to verify the validity of in vitro tests involving mSSCs by comparing their results with those of in vivo tests using C57BL/6 mice by gavage. We selected hydroxyurea (HU), which is known to chemically induce male reproductive toxicity. The 50% inhibitory concentration ($IC_{50}$) value of HU was 0.9 mM, as determined by the MTT assay. In the in vitro comet assay, % tail DNA and Olive tail moment (OTM) after HU administration increased significantly, compared to the control. Annexin V, PI staining and TUNEL assays showed that HU caused apoptosis in mSSCs. In order to compare in vitro tests with in vivo tests, the same substances were administered to male C57BL/6 mice. Reproductive toxicity was observed at 25, 50, 100, and 200 mg/kg/day as measured by clinical measures of reduction in sperm motility and testicular weight. The comet assay, DCFH-DA assay, H&E staining, and TUNEL assay were also performed. The results of the test with C57BL/6 mice were similar to those with mSSCs for HU treatment. Finally, linear regression analysis showed a strong positive correlation between results of in vitro tests and those of in vivo. In conclusion, the present study is the first to demonstrate the effect of HU-induced DNA damage, ROS formation, and apoptosis in mSSCs. Further, the results of the current study suggest that mSSCs could be a useful model to predict male reproductive toxicity.

• Toxicological Research
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• 제32권3호
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• pp.259-267
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• 2016

Animal testing was used traditionally in the cosmetics industry to confirm product safety, but has begun to be banned; alternative methods to replace animal experiments are either in development, or are being validated, worldwide. Research data related to test substances are critical for developing novel alternative tests. Moreover, safety information on cosmetic materials has neither been collected in a database nor shared among researchers. Therefore, it is imperative to build and share a database of safety information on toxicological mechanisms and pathways collected through in vivo, in vitro, and in silico methods. We developed the CAMSEC database (named after the research team; the Consortium of Alternative Methods for Safety Evaluation of Cosmetics) to fulfill this purpose. On the same website, our aim is to provide updates on current alternative research methods in Korea. The database will not be used directly to conduct safety evaluations, but researchers or regulatory individuals can use it to facilitate their work in formulating safety evaluations for cosmetic materials. We hope this database will help establish new alternative research methods to conduct efficient safety evaluations of cosmetic materials.

• Toxicological Research
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• 제30권3호
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• pp.185-191
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• 2014

Statistical methods are frequently used in toxicology, yet it is not clear whether the methods employed by the studies are used consistently and conducted based on sound statistical grounds. The purpose of this paper is to describe statistical methods used in top toxicology journals. More specifically, we sampled 30 papers published in 2014 from Toxicology and Applied Pharmacology, Archives of Toxicology, and Toxicological Science and described methodologies used to provide descriptive and inferential statistics. One hundred thirteen endpoints were observed in those 30 papers, and most studies had sample size less than 10, with the median and the mode being 6 and 3 & 6, respectively. Mean (105/113, 93%) was dominantly used to measure central tendency, and standard error of the mean (64/113, 57%) and standard deviation (39/113, 34%) were used to measure dispersion, while few studies provide justifications regarding why the methods being selected. Inferential statistics were frequently conducted (93/113, 82%), with one-way ANOVA being most popular (52/93, 56%), yet few studies conducted either normality or equal variance test. These results suggest that more consistent and appropriate use of statistical method is necessary which may enhance the role of toxicology in public health.

• Safety and Health at Work
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• 제2권1호
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• pp.34-38
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• 2011

Objectives: The antimicrobial activity of silver nanoparticles has resulted in their widespread use in many consumer products. Yet, despite their many advantages, it is also important to determine whether silver nanoparticles may represent a hazard to the environment and human health. Methods: Thus, to evaluate the genotoxic potential of silver nanoparticles, in vivo genotoxicity testing (OECD 474, in vivo micronuclei test) was conducted after exposing male and female Sprague-Dawley rats to silver nanoparticles by inhalation for 90 days according to OECD test guideline 413 (Subchronic Inhalation Toxicity: 90 Day Study) with a good laboratory practice system. The rats were exposed to silver nanoparticles (18 nm diameter) at concentrations of $0.7\;{\times}\;10^6$ particles/$cm^3$ (low dose), $1.4\;{\times}\;10^6$ particles/$cm^3$ (middle dose), and $2.9\;{\times}\;10^6$ particles/$cm^3$ (high dose) for 6 hr/day in an inhalation chamber for 90 days. The rats were killed 24 hr after the last administration, then the femurs were removed and the bone marrow collected and evaluated for micronucleus induction. Results: There were no statistically significant differences in the micronucleated polychromatic erythrocytes or in the ratio of polychromatic erythrocytes among the total erythrocytes after silver nanoparticle exposure when compared with the control. Conclusion: The present results suggest that exposure to silver nanoparticles by inhalation for 90 days does not induce genetic toxicity in male and female rat bone marrow in vivo.

• 한국응용곤충학회지
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• 제31권1호
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• pp.1-6
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• 1992

점박이응애(Tetranychus urticae Koch)에 대한 독성시험방법을 비교하고, 감수성계통을 누대도태하여 in vivo에서 저항성 발달수준과 in vitro에서의 AChE insensitivity의 관계를 실험한 결과는 다음과 같다. 점박이응애의 살비제 저항성 수준결정의 독성시험방법중 slide dip법 (CV=8.7%)은 leaf dip법(CV=12.2%) 이나 leaf disc법(CV=13.6%)보다 변이가 적고 정확도가 높을 뿐만 아니라 처리방법이 간편하고 한가지 농도에 대하여 여러 계통을 동시에 처리할 수 있고 처리 후의 조건을 균일하게 유지시킬 수 있으며 기주식물 없이 시험이 가능하였다. topical application법(CV=8.1%) 역시 정확도는 높았으나 시험 조작이 어렵고 필요한 장비의 구입 비용이 더 들며 시간이 많이 소요되는 단점이 있었다. 두 유기인제에 의한 누대도태결과 22세대 carbophenothion 도태개체군은 동일약제에 156배의 저항성이 발달하였으며, ethion에 대하여 128배의 저항성 반응을 보였다. 24세대 ethion 도태개체군은 동일약제에 64.1배의 저항성 발달이 되었으며, carbophenothion에 대하여도 65배의 저항성 반응을 보였다. 도태개체군의 AChE 활성저해도를 보면 감수성계통에 비하여 carbophenotion 누대계통은 carbohenothion은 3.3배, ethion은 2.7배의 활성저해도를 보였다. 또한 ethion 도태개체군에 대해서는 ethion은 2.6배 carbophenothion은 3.0배의 활성저해도를 나타냈다. 위와 같이 in vivo에서의 저항성 발달 수준과 in vitro에서의 AChE 저해도와는 밀접한 관계가 있는 것으로 보아 유기인계 살비제에 대한 점박이응애의 저항성 발현에는 AChE의 insensitivity가 주요인으로 작용하는 것으로 생각된다.