• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.7-16
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• 2012

Combustion Toxic Effects among several factors of risk encountered during fire are important in the evacuation and final survival, and they are broader and fatal than the direct damages caused by flame. Most studies on fire toxicity until the present are limited to fatality, mainly deaths by fire through pathological research. In this study, it is conducted as a fundamental experiment to address 3 principles of animal experiment and to provide an alternative test to animal testing that is regulated by national building codes and it was conducted through approval by the animal testing ethics committee. Hence, in this study average time of activity stop was measured after directly inhaling toxic gases (HCN) to laboratory animals (mice) through gas toxicity test (KS F 2271) for major asphyxiating gases(HCN) which are produced during fire combustion. effects of Combustion toxic gases on body were quantitatively analyzed through changes in internal organs and hematological analysis, and electrophoresis of a single cell of these laboratory animals. Biological conclusion of combustion toxicology is drawn through approaches (pathological examination, blood test, blood biochemical test, electrophoresis analysis of single cell) which could not confirmed in existing gas toxicity test.

• The Korean Journal of Applied Statistics
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• v.33 no.2
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• pp.123-136
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• 2020

It is common to encounter correlated multiple outcomes measured on the same subject in various research fields. In developmental toxicity studies, presence of malformed pups and fetal weight are measured on the pregnant dams exposed to different levels of a toxic substance. Joint analysis of such two outcomes can result in more efficient inferences than separate models for each outcome. Most methods for joint modeling assume a normal distribution as random effects. However, in developmental toxicity studies, the response distributions may change irregularly in location and shape as the level of toxic substance changes, which may not be captured by a normal random effects model. Motivated by applications in developmental toxicity studies, we propose a Bayesian joint model for binary and continuous outcomes. In our model, we incorporate a skewed logit model for the binary outcome to allow the response distributions to have flexibly in both symmetric and asymmetric shapes on the toxic levels. We apply our proposed method to data from a developmental toxicity study of diethylhexyl phthalate.

• Journal of Environmental Health Sciences
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• v.42 no.1
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• pp.27-33
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• 2016

Objectives: Alumina nanoparticles ($Al_2O_3$, Al-NPs) are used for various purposes, including as coating agents and paint additives. Their potential toxicity has raised concern for human health. This study focuses on exploring the toxic effects on the brain and kidneys caused by Al-NPs exposure in rats. Methods: The animals were orally administered Al-NPs at 10, 50 and 100 mg/kg body weight for 28 days following OECD TG 407. To determine the targeted toxicity of Al-NPs, histopathological examination and gene expression analysis were conducted on the rats. Results: The Al-NPs treatment induced kidney tubular dilatation. In the rat cerebrums, the expression levels of 126 genes experienced two-fold or greater increases in response to Al-NPs, including other genes encoding proteins involved in cell differentiation, transcription and signal transduction. In the rat kidneys, the expression levels of 152 genes also showed two-fold or greater increases in response to Al-NPs, including other genes encoding proteins involved in apoptosis, transcription and signal transduction. Conclusion: These results suggest that exposure to Al-NPs influences cellular signal pathways of kidney and cerebrum, and it can be a toxic indicators of nanometrials.

• Korean Journal of Pharmacognosy
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• v.40 no.1
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• pp.6-12
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• 2009

Thirty five methanol extracts from 19 natural local plants, which have been used as traditional anti-cancer medicine, were prepared. They were analyzed the cytotoxic effects on primary fibroblast cells and carcinoma cells. The root extract of Solanum nigrum were highly toxic in both cell lines with $IC_{50}$ values of less than $0.01{\mu}g/{\mu}l$, and 26 of 35 extracts were toxic in all cells with $IC_{50}$ values of $0.1{\sim}2{\mu}g/{\mu}l$. Three extracts including the fruit extracts of Solanum nigrum and Morus alba had no cytotoxic activity in both cell lines. Five of 35 extracts were highly toxic in cancer cells than in primary cells. Because primary cells were more resistant on these extracts, the five extracts were selected for anti-cancer agent candidates. Apoptosis or programmed cell death has an essential role in chemotherapy-induced tumor cell killing. Recently, inducers of apoptosis have been used in cancer therapy. When two of 5 cancer cell-specific cytotoxic extracts (Ulmus parvifolia and Zelkova serrata) were treated in concentration of $0.02{\sim}0.1{\mu}g/{\mu}l$, apoptosis were increased at 3-5 times in cancer cell lines. Finally, the apoptotic effects of these extracts were confirmed by cleavages of both poly-(ADP-ribose)-polymerase and caspase-3 as apoptotic markers. In this report, we suggested that two of 35 medicinal herb extracts can be useful anti-cancer drug candidates inducing apoptosis in several carcinoma cell lines.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.306-312
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• 2016

Microalgae are the potential bioindicators of environmental changes, for the environmental risk assessment as well as to set limits for toxic chemical release in the aquatic environment. Here, we evaluated the effects of two endocrine disrupting chemicals (EDCs), namely bisphenol A (BPA) and Aroclor 1016, on the green algae Tetraselmis suecica, diatom Ditylum brightwellii, and dinoflagellate Prorocentrum minimum. Each species showed wide different sensitivity ranges when exposed to these two EDCs; the 72 h effective concentration ($EC_{50}$) for these test species showed that Aroclor 1016 was more toxic than BPA. $EC_{50}$ values for the diatom D. birghtwellii were calculated at 0.037 mg/L for BPA and 0.002 mg/L for Aroclor 1016, representing it was the most sensitive when compared to the other species. In addition, these results suggest that these EDC discharge beyond these concentrations into the aquatic environments may cause harmful effect to these marine species.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1591-1596
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• 2006

Acaricidal effects of materials derived from Caesalpinia sappan heartwoods against Dermatophagoides farinae and D. pteronyssinus were assessed and compared with those evidenced by commercial benzyl benzoate and DEET. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the methanol extracts derived from C. sappan heartwoods were 6.13 and $5.44{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. Furthermore, the ethyl acetate fraction derived from the methanol extract was approximately 8.71 more toxic than DEET against D. farinae, and 4.73 times more toxic against D. pteronyssinus. The biologically active constituent from the ethyl acetate fraction of C. sappan heartwood extract was purified via silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by $GC-MS,\;^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C\;COSY-NMR$, and DEPT-NMR spectroscopy, and identified as juglone (5-hydroxy-l,4-naphthoquinone). Based on the $LD_{50}$ values of juglone and its derivatives, the most toxic compound against D. farinae was juglone ($0.076{\mu}g/cm^3$), followed by benzyl benzoate ($9.143{\mu}g/cm^3$) and 2methyl-l,4-naphthoquinone ($40.0{\mu}g/cm^3$). These results indicate that the acaricidal activity of C. sappan heartwoods is likely to be the result of the effects of juglone. Additionally, juglone treatment was shown to effect a change in the color of the cuticles of house dust mites, from colorless-transparent to dark brownish-black. Accordingly, as a naturally occurring acaricidal agent, C. sappan heartwood-derived juglone should prove to be quite 'useful as a potential control agent, lead compound, and house dust mite indicator.

• Molecular & Cellular Toxicology
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• v.2 no.1
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• pp.35-47
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• 2006

2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) are well known as the most toxic environmental compound in these days. Many researches are reported that dioxin produces multiple toxic effects, such as endocrine toxicity, reproductive toxicity, immunotoxicity and cancer. In this study, we carried to discover novel evidence for previously unknown gene expression patterns in human exposed to dioxin by using radioactive cDNA microarray. 548 workers who were divided into experimental and control groups according to their urinary Naphthol levels were enrolled in our study. Blood mRNA in human was isolated, and the gene expression profiles were analyzed by cDNA microarray. Gene expression analysis identified 52 genes which exhibited a significant change. In our study, most notably, genes involved in cell cycle, cell proliferation, signal transduction and apoptosis in human exposed to dioxin, such as CCND3, TSHR, and EFRN5, were up-regulated. In the current study, we observed gene expression of people that are exposed to dioxin using radioactive cDNA microarray. Through these results, we suggest when objects are exposed to toxic compounds, such as dioxin, the radioactive cDNA microarray may be using in sensitively detecting of cancerous change.

• Toxicological Research
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• v.35 no.1
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• pp.1-7
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• 2019

Mycotoxin contamination is a global phenomenon and causes a wide array of negative effects and other complications. This study focused on commonly found mycotoxins in Africa and the possible means of prevention or reduction of their contaminating effects. Mycotoxins are secondary metabolites of mold and fungi; they are generally toxic to living organisms. Hundreds of mycotoxins have been identified thus far, with some, such as aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, and patulin, considered agro-economically important. Several factors contribute to the presence of mycotoxins in food, such as climatic conditions, pest infestation, and poor harvest and storage practices. Exposure to mycotoxins, which occurs mostly by ingestion, leads to various diseases, such as mycotoxicoses and mycoses that may eventually result in death. In light of this, this review of relevant literature focuses on mycotoxin contamination, as well as various methods for the prevention and control of their prevalence, to avert its debilitating consequences on human health. Clear evidence of mycotoxin contamination is present in Africa, and it was therefore recommended that adequate prevention and control of these toxic substances in our food system should be encouraged and that appropriate measures must be taken to ensure food safety as well as the enhanced or long-lifespan of the African populace. Governments, research institutions, and non-governmental organizations should tailor the limited resources available to tackle mycotoxin prevalence, as these will offer the best prospects for successful development of a sustainable food system in Africa.

• Journal of Environmental Health Sciences
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• v.48 no.2
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• pp.106-115
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• 2022

Background: Current research suggests that humans are exposed to microplastics through consumption of foods and beverages, the airway route, and a variety of other means. Objectives: We evaluated oxidative stress and inflammation from polyethylene microplastics (PE-MPs) in the neonatal liver through intragastric administration or intratracheal instillation in pregnant mice. Methods: PE-MPs were administered from gestational day 9 to postnatal day 7. The intragastric administration group (0.01 mg/mouse/day or 0.1 mg/mouse/day) and intratracheal instillation group (6 ㎍/mouse/day or 60 ㎍/mouse/day) of PE-MPs were administered. After sacrifice, the oxidative stress and inflammation of the neonatal livers were measured. Results: As a result of the oxidative stress caused by PE-MPs in the neonatal livers, glutathione peroxidase decreased in a concentration-dependent manner in the intragastric administration group compared to the control group and intratracheal instillation decreased in high concentration PE-MPs. The catalase level increased at high concentrations of intragastric administration and intratracheal instillation. To confirm the level of inflammation caused by PE-MPs, monocyte chemoattractant protein-1 and tumor necrosis factoralpha were increased compared to the control group except for intratracheal intilation-high concentration PEMPs. The C-reactive protein level was decreased by intragastric administration compared to the control group and intratracheal instillation was increased compared to the control group. Conclusions: Despite the difficulty in comparing the toxic intensity between intragastric administration and intratracheal instillation of PE-MPs, our study revealed that oxidative stress and inflammation were induced in the neonatal liver. However, it is necessary to evaluate the toxic effects of microplastics on various organs as well. Overall, the present study indicates that the evaluation of toxic effects of long-term microplastic exposure, potential of microplastic toxicity on next-generation offspring and toxicity mechanism in human should be considered for further investigations.

• Journal of the korean veterinary medical association
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• v.6 no.2
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• pp.10-16
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• 1962

A rodenticide, sodium monofloroacetate, was administered to mice by introducing the rodenticide directly into the stomach, and the following observations were made. 1). Sings of intoxication were : incoordination and wobbly gait due to motor depression, d