• KSBB Journal
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• v.22 no.6
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• pp.414-420
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• 2007

Nanomaterials have been applied to various fields due to their advantageous characteristics such as high surface area, rapid diffusion, high specific surface areas, reactivity in liquid or gas phase, and a size close to biomacromolecules. Up to date, increased manufacturing and frequently use of the materials, however, revoke people's concerns on their hazard impact including toxicity the materials. Many research groups have carried out different protocols to evaluate toxic effects of nanomaterilas on different organisms, and consequently, nanomaterials are known to cytotoxicity. In this paper, we reviewed some of the most reports on toxic effects of several nanoparticles specifically on bacteria. There are numbers of reports focused on antibacterial effect of nanoparticles based on bacterial cell viability. Therefore, the application of each nanomaterial should be concerned with its toxicity and its toxic effect should be evaluated in terms of concentrations and sizes of the nanomaterials used, prior to use of a nanomaterial.

• Journal of Marine Life Science
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• v.3 no.2
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• pp.74-80
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• 2018

Mercury (Hg) poses a threat to marine ecosystem due to continuous inflow from various industries and bioaccumulation to higher trophic level via food web. Mercury can adversely affect growth, development, reproduction and metabolism to aquatic organisms. In the present study, acute toxicity and oxidative stress markers (total glutathione content, and activities of GST, GR and GPx) were investigated in brackish water flea Disphanosoma celebensis exposed to HgCl₂ for 24 h. As results, Hg showed negative effect in survival of D. celebensis. 24 h-LC₅₀ value was determined as 0.589 mg/l (95% C.I. 0.521~0.655 mg/l). After exposure to Hg (0.08 and 0.4 mg/l) for 24 h, total glutathione content was significantly decreased, whereas GST, GPx and GR activities were enhanced. These findings indicate that Hg induced oxidative stress in D. celebensis, and oxidative stress markers may be involved in cellular defense against Hg - mediated toxicity. This study provides a better understanding of molecular mode of action of Hg toxicity in this specie and potent of molecular markers for heavy metal monitoring in marine ecosystem.

• Journal of Preventive Medicine and Public Health
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• v.55 no.3
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• pp.280-288
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• 2022

Objectives: One of the most widely used pesticides today is chlorpyrifos (CPF). Cytochrome P450 (CYP)2B6, the most prominent catalyst in CPF bioactivation, is highly polymorphic. The objective of our study was to evaluate the role of CYP2B6^*6, which contains both 516G>T and 785A>G polymorphisms, in CPF toxicity, as represented by the concentration of 3,5,6-trichloro-2-pyridinol (TCPy), among vegetable farmers in Central Java, Indonesia, where CPF has been commonly used. Methods: A cross-sectional study was conducted among 132 vegetable farmers. Individual socio-demographic and occupational characteristics, as determinants of TCPy levels, were obtained using a structured interviewer-administered questionnaire and subsequently used to estimate the cumulative exposure level (CEL). TCPy levels were detected with liquid chromatography-mass spectrometry. CYP2B6^*6 gene polymorphisms were analyzed using a TaqMan^® SNP Genotyping Assay and Sanger sequencing. Linear regression analysis was performed to analyze the association between TCPy, as a biomarker of CPF exposure, and its determinants. Results: The prevalence of CYP2B6^*6 polymorphisms was 31% for ^*1/^*1, 51% for ^*1/^*6, and 18% for ^*6/^*6. TCPy concentrations were higher among participants with CYP2B6^*1/^*1 than among those with ^*1/^*6 or ^*6/^*6 genotypes. CYP2B6^*6 gene polymorphisms, smoking, CEL, body mass index, and spraying time were retained in the final linear regression model as determinants of TCPy. Conclusions: The results suggest that CYP2B6^*6 gene polymorphisms may play an important role in influencing susceptibility to CPF exposure. CYP2B6^*6 gene polymorphisms together with CEL, smoking habits, body mass index, and spraying time were the determinants of urinary TCPy concentrations, as a biomarker of CPF toxicity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.817-822
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• 1998

The biweekly monitoring of paralytic shellfish toxin on wild mussels (Mytilus corsucus) was carried out at Jangmok Bay, near Koje Island from Feb, 1996 to Feb. 1997. Toxicity and toxin composition were monitored by means of the mouse bioassay and HPLC. Paralytic shellfish toxin was detected from 27 March to 27 May and 28 November. This is the first record of paralytic shellfish toxin during autumn in Korean waters. Toxin composition between the two different season was similar and was composed of 5$\~$8 toxin fractions as GTXs STXs and PXs. The major toxin component in affected musssels shifted from GTXs in spring to PXs in autumn.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.156-157
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• 2003

The goal of this study is to develop a biomarker used in monitoring abnormal behaviors of Japanese medaka (Oryzias latipes) as a model organism caused by hazardous chemicals. Japanese medaka was treated under appropriate sublethal concentrations of copper and the fish were subjected to copper treatment after starvation for 48 hr. The untreated individuals showed common behavioral characteristics (i.e., smooth and linear movements with small curvatures) in the movement behaviors.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.484-490
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• 1999

Various materials including sodium alginate, k-carrageenan, collagen and polyacrylamide were studied in order to maintain the stability of bioluminescence of Photobacterium for the monitoring of volatile toxic substances. Kinetic parameters of specific rate($\mu$), and gamma(${\gamma}$) value were determined for the relationship between bioluminescence of immobilized P. phosphoreum and toxic substances. The bioluminescence intensity was found to be proportional to the concentration of toxic substances and the free cells were shown to be more sensitive than immobilized cells when volatile substances were exposed to the cells. Bioluminescence increased slightly after several minutes, which was due to the volatility of toxic compounds. Furthermore, P. phosphoreum immobilized on strontium alginate was better than cells immobilized on sodium alginate for the response to substances used.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.91-99
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• 1986

The single treatment of mice with steam distillate, non-volatile ether extract and methanol extract from mace (Arils of Myristica fragrans) caused a significant prolongation of hexobarbital-induced narcosis and increase in strychnine toxicity as well as a significant decrease in hepatic microsomal drug metabolizing enzyme activities. On 7 consecutive daily administrations, however, the duration of hypnosis was markedly shortened and significant increases in the hepatic enzyme activities were shown. With systematic fractionation by $SiO_2$ column chromatography of non-volatile ether fraction monitoring by animal tests a new lignan (mp $70{\sim}72^{\circ}$, MW 328, $[{\alpha}]^{20}_D+5.28$) was isolated as an active principle and its structure was elucidated as (2R, 3S)-1-(3,4-methylendioxyphenyl)-2,3 dimethyl-4-(4-hydroxy-3-methoxyphenyl) butane.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.1
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• pp.58-60
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• 2006

The venom gland of Toad contains large quantities of cardiac glycosides, and toad venom poisoning is similar to digitalis toxicity and carries a high mortality. Sometimes after ingestion of aphrodisiac pills which contain dried toad, a patient develops gastrointestinal symptoms and bradycardia, psychoneurologic symptoms. We have experienced 2 cases of toad venom intoxication, who ingested asian toads. Patients were presented to our ED with nausea, vomiting, and abdominal pain. The patients were peformed monitoring and conservative treatment and were fully recovered. Toad venom intoxication should be considered in patients with clinical manifestation of gastrointestinal irritation, cardiac arrhythmias, hyperkalemia, and detectable serum digoxin level without current medication of digoxin.

• Toxicological Research
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• v.1 no.1
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• pp.17-30
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• 1985

Mycotoxins are a group of toxicants giving a risk potential to human health in connection with the daily food intake. Food commodities once contaminated with mycotoxins can not be detoxified by any economic means and prevention was suggested as the only measure. In order to minimize the economic loss and health hazard posed by mycotoxins and toxicoses, systematic and toxicological studies on the subject should be undertaken. Most reports in Korea were concentrated on the mycological studies of relatively easy techniques and the confirmation or quantitation of mycotoxins was rarely done. Research topics to be undertaken in future may be exemplifid below: (1) Establishing assay methods for individual or multi-residue of mycotoxins (2) Monitoring of mycotoxins for suspicious food or feed samples in Korea (3) Epidemiological survey of mycotoxicoses (4) Etiological survey of disease outbreaks associated with mycotoxins (5) Accumulation of testing method and data on the toxicity of mycotoxins (6) Legal regulation to control mycotoxins and development of their detoxification / elimination methods

• Toxicological Research
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• v.29 no.1
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• pp.1-6
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• 2013

The process of drug discovery and development requires substantial resources and time. The drug industry has tried to reduce costs by conducting appropriate animal studies together with molecular biological and genetic analyses. Basic science research has been limited to in vitro studies of cellular processes and ex vivo tissue examination using suitable animal models of disease. However, in the past two decades new technologies have been developed that permit the imaging of live animals using radiotracer emission, X-rays, magnetic resonance signals, fluorescence, and bioluminescence. The main objective of this review is to provide an overview of small animal molecular imaging, with a focus on nuclear imaging (single photon emission computed tomography and positron emission tomography). These technologies permit visualization of toxicodynamics as well as toxicity to specific organs by directly monitoring drug accumulation and assessing physiological and/or molecular alterations. Nuclear imaging technology has great potential for improving the efficiency of the drug development process.