• Environmental Mutagens and Carcinogens
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• v.20 no.1
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• pp.7-13
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• 2000

The mechanisms of benzene toxicity is not fully elucidated, although the metabolism of benzene is very well understood. In order to study the mechanism of benzene toxicity, we investigated DNA damage induced by benzene metabolite, 1,2,4-benzenetriol (BT) in HL-60 cells by alkaline comet assay. To investigate the mechanism of cellular DNA damage induced by BT, the cells were treated with antioxidant such as vitamin C, SOD, catalase, and chelating agent such as deferoxamine (DFO), bathocuproinedisulfonic acid (BCDS). BT induced DNA damage in dose-dependent manner at concentration between 10$\mu\textrm{m}$ and 100$\mu\textrm{m}$. The antioxidant vitamin C itself induced DNA damage at higher concentration. The DNA damage induced by BT in HL-60 cells was protected at low concentraiton of vitamin C whereas no protective effect was found at high concentration. In hibitory effect of SOD on DNA damage by BT was observed and this suggested that BT produce superoxide anion (O2-) causing DNA damage. Catalase protected BT-induced DNA damage suggesting that BT produce H2O2 during autooxidation of BT. Both Fe(II)-specific cheiating agent, deferoxamine (DFO) and Cu(I)-specific chelating agent, bathocuproinedisulfonic acid (BCDS) inhibited BT0induced DNA damage. This suggested that DNA damage was caused by active species which was produced DAN damage. This suggested that DNA damage was caused by active species which was produced by the autooxidation of BT in the presence of Cu(II) and Fe(III). These findings suggest that reactive oxygen species play an important role in the mechanism of toxicity induced by benzene metabolites.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.509-517
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• 2008

DNA damage accumulates in cells as a result of exposure to exogenous agents such as benzopyrene, cigarette smoke, ultraviolet light, X-ray, and endogenous chemicals including reactive oxygen species produced from normal metabolic byproducts. DNA damage can also occur during aberrant DNA processing reactions such as DNA replication, recombination, and repair. The major of DNA damage affects the primary structure of the double helix; that is, the bases are chemically modified. These modification can disrupt the molecules'regular helical structure by introducing non-native chemical bonds or bulky adducts that do not fit in the standard double helix. DNA repair genes and proteins scan the global genome to detect and remove DNA damage and damage to single nucleotides. Direct reversal of DNA damage, base excision repair, double strand break. DNA repair are known relevant DNA repair mechanisms. Four different mechanisms are distinguished within excision repair: direct reversal, base excision repair, nucleotide excision repair, and mismatch repair. Genetic variation in DNA repair genes can modulate DNA repair capacity and alter cancer risk. The instability of a cell to properly regulate its proliferation in the presence of DNA damage increase risk of gene mutation and carcinogenesis. This article aimed to review mechanism of excision repair and to understand the relationship between genetic variation of excision repair genes and head and neck cancer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.5
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• pp.445-458
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• 1991

The literatures on meteorological disasters of which reported in Korea and abroad were reviewed and discussed in oilseed crops for refer to stable production and quality improvement of the crops. From the reviews, it was clarified that much of the reported disasters are almost same kinds as the other crops like reported in soybean and rice. However much of the disasters reported in oilseed crops were unconfirmed on their injury mechanisms or damage rate on yield loss and quality deteriorate comparing to the reports on soybean or rice. Among the meteorological disasters reported in oilseed crops, the disaters on sesame and groundnut were the most frequent in the numbers of report and water-flooding damage, drought damage, lodging damage in the kinds of disasters. Such kinds of the above disasters were leading to 90% yield loss in the most serious situation. To reduce the damage of meteorological disasters, it was suggested that the variety improvement of which highly resistant, and vinyl-mulching culture would be also an way to reduce water -logging and drought damage in sesame and groundnut in cultural practice. Further, it was indicated that the emphasis must be put on the oilseed crops to investigate and clarify the damage mechanisms, and reducing method of meteorological disasters in breeding and cultural practice.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.43-43
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• 2002

Mass spectrometric study of oxidant damage: Generation of endogenous oxidizing species have been implicated in the pathogenesis of a wide variety of diseases from cancer to Alzheimer's Disease to Inflammatory bowel diseases. Antioxidant compounds may therefore be useful in treating or preventing these diseases.(omitted)

• Proceedings of the Korean Society of Crop Science Conference
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• 1991.10a
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• pp.18-19
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• 1991

• Clinical and Experimental Pediatrics
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• v.55 no.6
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• pp.185-192
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• 2012

The prevalence of allergic diseases has increased worldwide, a phenomenon that can be largely attributed to environmental effects. Among environmental factors, air pollution due to traffic is thought to be a major threat to childhood health. Residing near busy roadways is associated with increased asthma hospitalization, decreased lung function, and increased prevalence and severity of wheezing and allergic rhinitis. Recently, prospective cohort studies using more accurate measurements of individual exposure to air pollution have been conducted and have provided definitive evidence of the impact of air pollution on allergic diseases. Particulate matter and ground-level ozone are the most frequent air pollutants that cause harmful effects, and the mechanisms underlying these effects may be related to oxidative stress. The reactive oxidative species produced in response to air pollutants can overwhelm the redox system and damage the cell wall, lipids, proteins, and DNA, leading to airway inflammation and hyper-reactivity. Pollutants may also cause harmful effects via epigenetic mechanisms, which control the expression of genes without changing the DNA sequence itself. These mechanisms are likely to be a target for the prevention of allergies. Further studies are necessary to identify children at risk and understand how these mechanisms regulate gene-environment interactions. This review provides an update of the current understanding on the impact of air pollution on allergic diseases in children and facilitates the integration of issues regarding air pollution and allergies into pediatric practices, with the goal of improving pediatric health.

• BMB Reports
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• v.38 no.5
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• pp.507-516
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• 2005

Antimicrobial peptides (AMPs) have been isolated and characterized from tissues and organisms representing virtually every kingdom and phylum. Their amino acid composition, amphipathicity, cationic charge, and size allow them to attach to and insert into membrane bilayers to form pores by 'barrel-stave', 'carpet' or 'toroidal-pore' mechanisms. Although these models are helpful for defining mechanisms of AMP activity, their relevance to resolving how peptides damage and kill microorganisms still needs to be clarified. Moreover, many AMPs employ sophisticated and dynamic mechanisms of action to carry out their likely roles in antimicrobial host defense. Recently, it has been speculated that transmembrane pore formation is not the only mechanism of microbial killing by AMPs. In fact, several observations suggest that translocated AMPs can alter cytoplasmic membrane septum formation, reduce cell-wall, nucleic acid, and protein synthesis, and inhibit enzymatic activity. In this review, we present the structures of several AMPs as well as models of how AMPs induce pore formation. AMPs have received special attention as a possible alternative way to combat antibiotic-resistant bacterial strains. It may be possible to design synthetic AMPs with enhanced activity for microbial cells, especially those with antibiotic resistance, as well as synergistic effects with conventional antibiotic agents that lack cytotoxic or hemolytic activity.

• Molecules and Cells
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• v.41 no.1
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• pp.35-44
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• 2018

Mitochondria are responsible for supplying of most of the cell's energy via oxidative phosphorylation. However, mitochondria also can be deleterious for a cell because they are the primary source of reactive oxygen species, which are generated as a byproduct of respiration. Accumulation of mitochondrial and cellular oxidative damage leads to diverse pathologies. Thus, it is important to maintain a population of healthy and functional mitochondria for normal cellular metabolism. Eukaryotes have developed defense mechanisms to cope with aberrant mitochondria. Mitochondria autophagy (known as mitophagy) is thought to be one such process that selectively sequesters dysfunctional or excess mitochondria within double-membrane autophagosomes and carries them into lysosomes/vacuoles for degradation. The power of genetics and conservation of fundamental cellular processes among eukaryotes make yeast an excellent model for understanding the general mechanisms, regulation, and function of mitophagy. In budding yeast, a mitochondrial surface protein, Atg32, serves as a mitochondrial receptor for selective autophagy that interacts with Atg11, an adaptor protein for selective types of autophagy, and Atg8, a ubiquitin-like protein localized to the isolation membrane. Atg32 is regulated transcriptionally and post-translationally to control mitophagy. Moreover, because Atg32 is a mitophagy-specific protein, analysis of its deficient mutant enables investigation of the physiological roles of mitophagy. Here, we review recent progress in the understanding of the molecular mechanisms and functional importance of mitophagy in yeast at multiple levels.

• Korean Journal of Exercise Nutrition
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• v.24 no.3
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• pp.39-43
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• 2020

[Purpose] In this literature review we aimed to investigate the effects of curcumin supplementation on delayed onset muscle soreness (DOMS), which occurs after exercise, and evaluate related parameters to propose practical recommendations for the field of exercise physiology. [Methods] Experimental studies conducted on curcumin supplementation and DOMS were systematically reviewed to determine (1) the effect of curcumin supplementation on DOMS, (2) potential mechanisms by which curcumin supplementation may attenuate DOMS, and (3) practical considerations for curcumin supplementation. [Results] While several studies have reported that curcumin supplementation attenuates DOMS after exercise, others have reported that curcumin supplementation has no effect on DOMS. Several mechanisms have been proposed by which curcumin supplementation may attenuate DOMS; the most probable of which is a reduction in inflammatory response. Other potential mechanisms include modulation of transient receptor potential vanilloid 1 (TRPV1) or changes in post-exercise capillary lactate levels; these require further examination. The usual recommended dose of curcumin is 150-1500 mg daily (sometimes up to 5 g), divided into 2-3 portions and taken before and after exercise. It is not necessary to take curcumin together with piperine. [Conclusion] Although conflicting results regarding the effects of curcumin supplementation on DOMS exist in literature, it may be considered as a method of nutritional intervention for reducing post-exercise DOMS.

• Journal of Environmental Policy
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• v.2 no.1
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• pp.107-135
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• 2003

This study reviews the proposed liability and redress regime under the Cartagena Protocol on Biodiversity. Several core elements for the regime are discussed in comparison with those listed in the 1999 Basel Protocol on Liability and Compensation for Damage resulting from the Transboundary Movements of Hazardous Wastes and their Disposal. These are (1) scope of the rules and procedures; (2) channeling of liability; (3) legal standing; (4) definition of damage; (5) standard of care; (6) ancillary sources of compensation; (7) limitation of liability; (8) financial guarantees; and (9) mutual recognition and enforcement of judgments. Korea has given relatively little attention to the issue of liability and redress in the context of LMOs trade. As the Protocol is expected to enter into force soon, Korea needs to develop appropriate implementing domestic mechanisms for the Biosafety Protocol. Establishing an adequate domestic liability and compensation scheme will be one of the most important mechanisms not only to comply the Protocol but to ensure safety of LMOs in general. A further research is needed on the basis of a comparision of relevant legislations in different countries as well as analysis of current laws related to the accidents arising from LMOs trade, such as product liability laws, food safety laws, liability provisions in some environmental legislations.