• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.294-305
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• 1989

Basedon statistical data of pomfret (Pampus spp.) catches by the stow net during $1970\~1985$, the distribution and migration of pomfrets and fishing conditions were investigated in relation to oceanographic conditions, in the East China Sea and the Yellow Sea. The main fishing grounds of Pomfrets were formed around the Great Yangtze Sand Bank which locates between the Cheju Island and the mouth of the Yangtze River. Its area occupied only 11 percent of all fishing grounds, and about 70 percent of total catch was found there. The coefficient of variation(CV) in catch was below 0.01 in the whole fishing grounds and that of tile main fishing grounds (14 fishing areas) was $0.001\~0.003$. This area was indicated markedly by the inflow of Yellow Sea Warm Current from spring to autumn, and this mixing area which formed the oceanic front among the China Continental Shelf Water, the Yellow Sea Bottom Cold Water and the Tsushima Warm Current. The pomfrets migrates to south-north according to the expansion and contraction of the Tsushima Warm Current including the Yellow Sea Warm Current and the Yellow Sea Bottom Cold Water. Therefore, it migrates to north of the Yellow Sea in summer and to southern part of the East China Sea in winter. The most frequent range of the water type for high catch was $10\~12^{\circ}C$ in temperature and $32.4\~33.4\%_{circ}$ in salinity. The ranges was occupied more than 70 percent of total catch on fishing season. The frequency range of the water type was not different between the abundant fishing periods and the poor fishing periods in terms of the maximum catches.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5873-5878
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• 2014

Hypoxia and autophagy are known to facilitate tumor progression. We here aimed to investigate the role of hypoxia-associated autophagy in cholangiocarcinoma (CCA) survival and metastasis. Immunostaining of hypoxic-responsive proteins (HIF-$1{\alpha}$ and BNIP3) and a key regulator of autophagy (PI3KC3) were examined in CCA tissues and their expression levels were compared with clinicopathological parameters. A hypoxia mimicking condition ($CoCl_2$ treatment) was also tested regarding CCA cell functions. Our results showed that HIF-$1{\alpha}$ (66%), BNIP3 (44%) and PI3KC3 (46%) showed strong staining in human CCA tissues. Positive expression of HIF-$1{\alpha}$ (p=0.033), BNIP3 (p=0.040) and PI3KC3 (p=0.037) was significantly correlated with lymph node metastasis. HIF-$1{\alpha}$ was well associated with BNIP3 (r=0.3, p<0.01) and PI3KC3 (r=0.2, p<0.01). The survival rates of patients who were positive with HIF-$1{\alpha}$ (p=0.047) or co-expressed HIF-$1{\alpha}$ and BNIP3 (p=0.032) or HIF-$1{\alpha}$ and PI3KC3 (p=0.043) were significantly greater than in the negative groups. CCA cells treated with $CoCl_2$ showed an increase in HIF-$1{\alpha}$, BNIP3, PI3KC3 and LC3-II, with increased cell migration and pFAK levels. These data suggest that hypoxia associated autophagy enhances CCA metastasis, resulting in a poor prognosis of CCA.

• Korean Journal of Head & Neck Oncology
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• v.33 no.1
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• pp.21-29
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• 2017

Methylation of CpG islands in the promoter region of genes acts as a significant mechanism of epigenetic gene silencing in head and neck squamous cell carcinoma (HNSCC). DNA methylation markers are particularly advantageous because DNA methylation is an early event in tumorigenesis, and the epigenetic modification, 5-methylcytosine, is a stable mark. In the present study, we assessed the genome-wide preliminary screening and were to identify novel methylation biomarker candidate in HNSCC. Genome-wide methylation analysis was performed on 10 HNSCC tumors using the Methylated DNA Isolation Assay (MeDIA) CpG island microarray. Validation was done using immunohistochemistry using tissue microarray of 135 independent HNSCC tumors. In addition, in vitro proliferation, migration/invasion assays, RT-PCR and immunoblotting were performed to elucidate molecular regulating mechanisms. Our preliminary validation using CpG microarray data set, immunohisto-chemistry for HNSCC tumor tissues and in vitro functional assays revealed that methylation of the Homeobox B5 (HOXB5) and H6 Family Homeobox 2 (HMX2) could be possible novel methylation biomarkers in HNSCC.

• Journal of Life Science
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• v.19 no.12
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• pp.1851-1854
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• 2009

This study correlated changes in the plasma levels of estradiol-$17{\beta}$ (E2) with changes in the gonadosomatic index (GSI) and ovarian development during the annual reproductive cycle of the pike eel Muraenesox cinereus, collected at the Tongyung coast region. Ovarian maturity was classified based on histological observations; the perinucleolus stage (November to February), the oil droplet stage (March to April), the early vitellogenic stage (April to May) and the late vitellogenic stage (June to October). Seasonal changes in the GSI were correlated with water temperature and reflected the degree of ovarian maturity. Plasma E2 levels were correlated with changes in the GSI, which increased from April to a peak in July, and the levels remained comparatively high until October. These data indicated that changes in the GSI and plasma E2 levels are correlated with the annual ovarian activity of the pike eel. In this study, however, female pike eels were not collected during the spawning stage. Therefore, spawning of this species seemed to be closely related to its migration toward the deep sea of offshore.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.85-94
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• 2001

The vertical distribution and activity patterns of fishes during the evening and morning transitions were investigated acoustically and by pelagic trawling on October 2-10, 1997 in the Korean Eastern Sea. The acoustic data were collected from four stations with a scientific echo sounder operating at a frequency of 38 kHz, and the echogram was used to analyze the diel vertical migration of fish. Biological sampling was accomplished by pelagic trawling to identify fish species recorded on the echograms, and the species and length compositions were investigated. Vertical profiles of water temperature, salinity at the trawl station were taken with a CTD system and were related to the diel movement and the depth distribution of fish. During the day, one group of fish mainly distributed above the depth layer of 50 m, the other group was at deeper water, approximately 250 m, but began to migrate toward the surface before sunset with a time difference. During the night, they were dispersed between the surface and the depth of 125 m. Just prior to sunrise, the scattering layer was divided with 2 groups and began to migrate downwards, respectively. Several trials of pelagic trawling for scattering layers suggest that the most dominant scatterer in the survey area of this study was Japanese flying squid, Todarodes pacificus..

• Toxicological Research
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• v.29 no.1
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• pp.43-52
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• 2013

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by several species of Fusarium that are found in cereals and agricultural products. ZEN has been implicated in mycotoxicosis in farm animals and in humans. The toxic effects of ZEN are well known, but the ability of an alkaline Comet assay to assess ZEN-induced oxidative DNA damage in Chang liver cells has not been established. The first aim of this study was to evaluate the Comet assay for the determination of cytotoxicity and extent of DNA damage induced by ZEN toxin, and the second aim was to investigate the ability of N-acetylcysteine amide (NACA) to protect cells from ZEN-induced toxicity. In the Comet assay, DNA damage was assessed by quantifying the tail extent moment (TEM; arbitrary unit) and tail length (TL; arbitrary unit), which are used as indicators of DNA strand breaks in SCGE. The cytotoxic effects of ZEN in Chang liver cells were mediated by inhibition of cell proliferation and induction of oxidative DNA damage. Increasing the concentration of ZEN increased the extent of DNA damage. The extent of DNA migration, and percentage of cells with tails were significantly increased in a concentration-dependent manner following treatment with ZEN toxin (p < 0.05). Treatment with a low concentration of ZEN toxin (25 ${\mu}M$) induced a relatively low level of DNA damage, compared to treatment of cells with a high concentration of ZEN toxin (250 ${\mu}M$). Oxidative DNA damage appeared to be a key determinant of ZEN-induced toxicity in Chang liver cells. Significant reductions in cytolethality and oxidative DNA damage were observed when cells were pretreated with NACA prior to exposure to any concentration of ZEN. Our data suggest that ZEN induces DNA damage in Chang liver cells, and that the antioxidant activity of NACA may contribute to the reduction of ZEN-induced DNA damage and cytotoxicity via elimination of oxidative stress.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.146-156
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• 2018

Spermidine is a naturally occurring polyamine compound that has recently emerged with anti-aging properties and suppresses inflammation and oxidation. However, its mechanisms of action on anti-inflammatory and antioxidant effects have not been fully elucidated. In this study, the potential of spermidine for reducing pro-inflammatory and oxidative effects in lipopolysaccharide (LPS)-stimulated macrophages and zebrafish was explored. Our data indicate that spermidine significantly inhibited the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$), and cytokines including tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$ in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects of spermidine accompanied by a marked suppression in their regulatory gene expression at the transcription levels. Spermidine also attenuated the nuclear translocation of $NF-{\kappa}B$ p65 subunit and reduced LPS-induced intracellular accumulation of reactive oxygen species (ROS) in RAW 264.7 macrophages. Moreover, spermidine prevented the LPS-induced NO production and ROS accumulation in zebrafish larvae and was found to be associated with a diminished recruitment of neutrophils and macrophages. Although more work is needed to fully understand the critical role of spermidine on the inhibition of inflammation-associated migration of immune cells, our findings clearly demonstrate that spermidine may be a potential therapeutic intervention for the treatment of inflammatory and oxidative disorders.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.88-92
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• 2007

Isopropylthioxanthone(ITX) is used as a photoinitiator In UV-cured inks, triggering the radical polymerization of the acrylic component of such inks and thus causing the liquid ink film to cure. Recently ITX was detected in carton packed food in Italy. In order to cope with risk issues of overseas and acquire monitoring data on ITX, we have established the method using HPLC/FLD for ITX analysis after reviewing parameters of the analytical methods. Limit of detection (LOD) and limit of quantification (LOQ) were 0.02 ppb and 0.1 ppb, and linearity and RSD (%) were 0.9991 and 1.09, respectively. We have investigated ITX levels migrated to food on 87 commercial products packed in carton and ITX was not detected any food. Therefore it is supposed that UV-cured ink containing ITX as photoinitiator is not currently used in printing of carton pack in Korea.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.286-294
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• 2017

Development of transportation is rapidly reducing the barriers between countries, but this is causing the easier migration of species than the past. Typically, exotic species are imported for the purpose of food, leather, and pets. However, it has been introduced into the wild through artificially or naturally paths, and recently they are become a main cause of ecosystem disturbance. In this study, we investigated exotic turtle species introduced into the wild and analyzed their distribution characteristics. As a result of filed surveys, totally 4 genus 8 species 62 individuals of exotic turtles were found from 126 reservoirs in Gangwon-do and Gyeongsangnam-do, South Korea. In particular, Trachemys scripta elegans showed relatively high frequency than other turtle species and the natural reproduction of T. s. elegans was confirmed in some areas. On the other hand, the frequency of discovery of exotic turtles except T. s. elegans was relatively low, and the range of the areas was limited. Especially, exotic turtles except T. s. elegans were mainly found in public places such as reservoirs in the park. As a result of analyzing the distribution characteristics of exotic turtles using geographic information system, the turtles' distribution showed a high correlation with the artificial factor such as "urban". In this study, we identified the distribution characteristics of exotic turtles in the Korean wild, and these results will be important data for understanding status the and establishing effective management methods for exotic species.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2465-2477
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• 2015

The number of emigrants along with globalization and internationalization is rapidly increasing. The international migration is creating a new form of acculturation and a new structure of society. Racial or cultural diversity resulting from political, economical, and cultural exchange is drastically increasing. This study aimed to provide policy plans or basic data to improve multicultural acceptability in the future. Accordingly, it was also to set and verify causal effect of multicultural acceptability. For those purposes, a questionnaire was made up based on the literature about acculturation, and a survey was taken in korean. The results are as follows. Dependant variables used in analysis were sub-factors of multicultural acceptability founding three types called 'The Actual Acceptance', 'The Active Acceptance', 'The Passive Acceptance'. It was found that positive effect in multicultural acceptability through media experience was an important factor to reduce discriminant of multicultural community members. Therefore, we need to produce diverse media programs that can improve multicultural acceptability and reduce negative perception of multicultural community members. Additionally, multiculture education to help understanding of other races and other cultures should be developed as subject courses in university.