• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.151-164
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• 2006

We monitored the current macrozoobenthic community structure after the Sea Prince oil spill around Keumo-do and Sori-do, Korea. Macrobenthic animals were collected seasonally around Sori-Keumo do using a van Veen grab ($0.1m^2$) from October 1999 to April 2000. In total, 196 species were identified at 46 sites around Keumho-do. The mean density was 1,460 individuals/$m^2$, and polychaetes comprised 80% of the total density of the macrozoobenthic. Dominant species were the polychaete Tharyx sp. (51%), the echinoderm Amphioplus megapomus (5%) and the polychaete Lumbrineris longifolia (3%). We identified 176 macrobenthic species at 36 sites around Sori-do. The mean density was 1,068 individuals/$m^2$, and polychaetes was the most abundant faunal group, comprising 41%, followed by mollusks (24%) and echinoderms (20%). Dominant species in Sori-do were the mollusk Potamocorbula amurensis (23%), the chinoderm Amphioplus megapomus (14%), and the polychaete Tharyx sp. (10%). The overall community structures in the study area showed few seasonal changes, although there was a gradual change in the species composition within each benthic community. Tharyx sp. was the most abundant species in the study area. Because this species has not been found in the other coastal areas except during recent investigations, it is considered to have increased during the course of community succession after the oil spill. The macrozoobenthic around Keumo-do showed little change in species richness, whereas around Sori-do, it showed a few increases in species richness after the summer of 1998. The overall density showed the same trend as species richness. Based on improved community indices, we suggest that the macrozoobenthic communities around Sori-Keumo Islands are gradually recovering from the oil-spill damagecaused by the oil spill.

• The Korean Journal of Petroleum Geology
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• v.1 no.1 s.1
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• pp.1-13
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• 1993

The diagenetic history of the carbonate rocks of the Mungok Formation near Machari area, Kangwondo, was investigated based on textural, isotopic, and chemical data. Paragenetic relationship among diagenetic minerals, coupled with their distinct geochemical contents, shows that the Mungok Formation have undergone several stages of diagenetic events: 1) shallow marine, 2) meteoric, 3) shallow to intermediate burial, and 4) deep burial diagenesis. Shallow marine diagenesis includes fibrous calcite cementation, micritization, and framboidal pyritization, and meteoric diagenesis involved dissolution and recrystallization of unstable allochems (both aragonite and HMC), syntaxial overgrowth on echinoderm fragments, and equant calcite cementation. During shallow to intermediate burial, idiotopic dolomite and chert formed, and xenotopic dolomitization took place before stylolitization of the rocks. After the rocks were deeply buried, saddle dolomitization, second stage of silicification, and dedolomitization occurred.

• Journal of Biomedical Engineering Research
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• v.45 no.1
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• pp.20-25
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• 2024

Extracellular vesicles (EVs) are nano-sized lipid bilayer vesicles released by cells. EVs act as messengers for cell-to-cell communication. Inside, it contains various substances that show biological activity, such as proteins, lipids, nucleic acids, and metabolites. The study of EVs extracted from terrestrial organisms and stem cells on inflammatory environments and tissue regeneration have been actively conducted. However, marine organisms-derived EVs are limited. Therefore, we have extracted EVs from sea urchins belonging to the Echinoderm group with their excellent regenerative ability. First, we extracted extracellular matrix (ECM) from sea urchin gonads treated with hypotonic buffer, followed by collagenase treatment, and filtration to collect ECM-bounded EVs. The size of sea urchin gonad-derived EVs (UGEVs) is about 20-100 nm and has a round shape. The protein content was higher after EVs burst than before, which is evidence that proteins are contained inside. In addition, proteins of various sizes are distributed inside. PKH-26 was combined with UGEVs, which means that UGEVs have a lipid membrane. PHK-26-labeled UGEVs were successfully uptaken by cells. UGEVs can be confirmed to have the same characteristics as traditional EVs. Finally, it was confirmed that Schwann cells were not toxic by increasing proliferation after treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3927-3932
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• 2014

Background: Epidermal growth factor receptor (EGFR) mutations and echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) define specific molecular subsets of lung adenocarcinomas with distinct clinical features. Our purpose was to analyze clinical features and prognostic value of EGFR gene mutations and the EML4-ALK fusion gene in lung adenocarcinoma. Patients and Methods: EGFR gene mutations and the EML4-ALK fusion gene were detected in 92 lung adenocarcinoma patients in China. Tumor marker levels before first treatment were measured by electrochemiluminescence immunoassay. Results: EGFR mutations were found in 40.2% (37/92) of lung adenocarcinoma patients, being identified at high frequencies in never-smokers (48.3% vs. 26.5% in smokers; P=0.040) and in patients with abnormal serum carcinoembryonic antigen (CEA) levels before the initial treatment (58.3% vs. 28.6%, P=0.004). Multivariate analysis revealed that a higher serum CEA level before the initial treatment was independently associated with EGFR gene mutations (95%CI: 1.476~11.343, P=0.007). We also identified 8 patients who harbored the EML4-ALK fusion gene (8.7%, 8/92). In concordance with previous reports, younger age was a clinical feature for these (P=0.008). Seven of the positive cases were never smokers, and no coexistence with EGFR mutation was discovered. In addition, the frequency of the EML4-ALK fusion gene among patients with a serum CEA concentration below 5ng/ml seemed to be higher than patients with a concentration over 5ng/ml (P=0.021). No significant difference was observed for time to progression and overall survival between EML4-ALK-positive group and EML4-ALK-negative group or between patients with and without an EGFR mutation. Conclusions: The serum CEA level before the initial treatment may be helpful in screening population for EGFR mutations or EML4-ALK fusion gene presence in lung adenocarcinoma patients.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.157-168
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• 2000

Sea urchin S. intermedius occurring in the Korean east coast is a cold water species that belongs to the family Strongylocentrotidae of Echinoidea. Although it is known that there are nine species in the family, species identification criteria, phylogenetic relationships, time and process of evolution of the family members have not been uncovered clearly. In the present study, I tried to find some clues to such problems for S. intermedius by means of DNA sequences. For this, cytochrome c oxidase subunit I (COI), one of the mitochondrial genes that evolve fast and follow maternal inheritance was analyzed. DNA was extracted from the female gonad of S. intermedius, a segment of COI gene amplified by polymerase chain reaction (PCR), and finally a total of 1077 base pair sequence of COI obtained by cloning and sequencing the PCR product. The sequence was compared with homologous genes of other sea urchins and echinoderm species. Phylogenetic trees of the COI gene segment revealed that S. intenedius is a sister species of S. purpuratus which lives along the east coast of the Paciflc. With reference to the fossil records of sea urchins and genetic distances in the molecular phylogenies, it is estimated that the two species were separated about 0.89 million years ago when the earth temperature fluctuated significantly. The current disjunct distribution patterns of the two species and the climate change of the earth at the time of separation suggest that speciation might have occurred by vicariance. The COI gene sequence obtained here now can be used as a molecular character which discerns S. intermedius from the other sea urchin species of Strongylocentrotidae.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.171-180
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• 2009

Based on the constituent analysis of sediments near Dok Island, the origin and sedimentary facies were Investigated. The sediments are mainly from originated from volcanic and volcaniclastic rock fragments derived from Dok Island and carbonate sediments formed by a variety of shallow-dwelling organisms that secreted calcareous skeletons. Carbonate producers include mollusks (bivalves and gastropods), encrusting & branching bryozoans, encrusting & segmented red algae, worm tubes, barnacles, diatoms, sponge spicules and echinoderm fragments. The distribution and relative amount of these constituents are basically dependent upon water depth and grain size even though local variations can be observed within the same depth interval. Five sedimentary facies can be divided: nearshore facies (<20 m), neritic facies ($20{\sim}100m$), upper transitional facies ($100{\sim}200m$), lower transitional facies ($200{\sim}700m$), and hemipelagic facies (>700 m). The sediments that were sampled below the water depth of 2,000 m still contain a significant amount of carbonates (ca. $10{\sim}20%$), implying that the carbonate compensation depth in the East Sea may well exceed this water depth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.161-174
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• 1997

A study on the distribution of the major domiant species of macrobenthos was carried out in Chinhae Bay from lune 1987 to May 1990. The 13 dominant species, based on the number of individuals and frequency, occupied more than $70\%$ of the total individuals. Of these species, 11 species represented polychaetes $(85\%)$ and 2 species molluscs $(15\%)$. The dominant species included Lumbrineris longifolia, Paraprionospio pinnata and Theora fragilis, with a density of $173.3({\pm}55.4),\;169.3({\pm}257.8)\;and\;81.8({\pm}93.3)\;ind./m^2$, respectively. In terms of biomass these dominant species occupied move than $75\%$ of the total biomass of the macrobenthos. These were composed of 6 species of polychaetes, 7 of molluscs and one echinoderm. The biomass of Macoma tokyoensis, Periglypta cf. puerpera and Paraprionospio pinnata were predominant (more than $45\%$ of the total biomass), and their biomass were $14.69({\pm}30.17),\;8.71({\pm}29.40),\;4.17({\pm}11.93)g/m^2$, respectively. In terms of density, distribution patterns of Lumbrineris iongifolia, Paraprionospio pinnata, Aricidea jeffreysii, Magelona japonica, Sigambra tentaculata, Raetellops pulchella, Glycinde gurjanovae were discussed. In the inner area of the bay with high organic content, Lumbrineris longifolia, Paraprionospio pinnata, Aricides jeffreysii, Sigambra tentaculata, Raetellops pulchella were pvedominant, whereas in the mouth of the bay with low organic content, Magelona japonica, Glycinde gurjanovae, Sternaspis scutata, Theora fragilis were dominant. Lumbrineris longifolia was widly distributed throughout the bay. However, Paraprionospio pinnata, Aricidea jeffreysii and Sigambra tentaculata had high density particularly in the central pan of the bay where there was high organic content in surface sediment, and these species possibly can be used as the potential pollution indicating species.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.153-165
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• 2014

Carbon dioxide capture and storage (CCS) technology is recognizing one of method responding the climate change with reduction of carbon dioxide in atmosphere. In Korea, due to its geological characteristics, sub-seabed geological $CO_2$ storage is regarded as more practical approach than on-land storage under the goal of its deployment. However, concerns on potential $CO_2$ leakage and relevant acidification issue in the marine environment can be an important subject in recently increasing sub-seabed geological $CO_2$ storage sites. In the present study effect data from literatures were collected in order to conduct an effect assessment of elevated $CO_2$ levels in marine environments using a species sensitivity distribution (SSD) various marine organisms such as microbe, crustacean, echinoderm, mollusc and fish. Results from literatures using domestic species were compared to those from foreign literatures to evaluate the reliability of the effect levels of each biological group and end-point. Ecological effect guidelines through estimating level of pH variation (${\delta}pH$) to adversely affect 5 and 50% of tested organisms, HC5 and HC50, were determined using SSD of marine organisms exposed to the $CO_2$-induced acidification. Estimated HC5 as ${\delta}pH$ of 0.137 can be used as only interim quality guideline possibly with adequate assessment factor. In the future, the current interim guideline as HC5 of ${\delta}pH$ in this study will look forward to compensate with supplement of ecotoxicological data reflecting various trophic levels and indigenous species.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.124-133
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• 2009

The study was performed to investigate the community structure of macrobenthic fauna during June 2005, in Hallyeohaesang National Park from Korea Strait. A total of 284 macrobenthic fauna were collected. The overall average macrobenthic density and biomass were 2,002 individuals m$^{-2}$ and 154.92 gWWt m$^{-2}$, respectively. Based on the Lebris (1988) index, there were 20 species accounting for approximately 47.64% of total individuals. And the highest densities were found in the polychaetes Scoletoma longifolia, Isolda pulchella, Mediomastus californiensis, Minuspio multibranchia, Tharyx sp. 1 and the bivalve Theora fragilis. On the other hand, the top twenty species made up 70.47% of the total biomass while the three most abundant, the echinoderms Schizaster lacunosus, Amphiura vadicola and the bivalve Fulvia mutica. The conventional multivariate statistics (cluster analysis and non-metric Multi-Dimensional Scaling) applied to assess spatial variation in macrobenthic assemblages. As a result of cluster analysis and nMDS ordination, this study area was divided into two different groups of stations and species. In case of station, there are two groups: one is a mud dominated station group and the other is dead shell and sand dominated group. And the 2 faunistic groups were established as follows: 1) a group of relatively higher abundances in mud dominated sediment. There were numerically dominated by the polychaetes Magelona japonica, Sternaspis scutata, Paraprionospio pinnata, Tharyx sp. 1 and the amphipods Monocorophium sinense and Eriopisella sechellensis. 2) a group of relatively higher densities dead shell and sand dominated sediment. These groups were characterized by the polychaetes I. pulchella, M. multibranchiata, the amphipods M. acherusicum, Gammaropsis japonicus and the echinoderm A. vadicola.