• Journal of Yeungnam Medical Science
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• v.36 no.2
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• pp.85-91
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• 2019

The incidence of gastric mucosa-associated lymphoid tissue (MALT) lymphoma is increasing worldwide, but the diagnosis is difficult. Most patients are asymptomatic or complain of nonspecific gastrointestinal symptoms. As the endoscopic features of gastric MALT lymphoma are variable and nonspecific, the possibility of this condition may be overlooked during esophagogastroduodenoscopy, and it remain undiagnosed. Therefore, this condition needs to be considered when an abnormal mucosa is observed during this procedure. Biopsy performed during endoscopy is the primary diagnostic test, but false negative results are possible; large numbers of samples should be collected from both normal and abnormal mucosae. Endoscopic ultrasonography is useful to assess the depth of invasion and to predict the treatment response. After treatment, follow-up tests are required every 3 months until complete remission is achieved, and annually thereafter. Early diagnosis of gastric MALT lymphoma is difficult, and its diagnosis and follow-up require wide experience and competent endoscopic technique.

• Journal of Species Research
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• v.8 no.1
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• pp.128-135
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• 2019

Two euplotid ciliates, Euplotes encysticus Yonezawa, 1985 and E. rariseta Curds et al., 1974, were isolated from a freshwater pond called Mulgol in Dokdo of the East Sea and from Masan Bay/Jeju Island, Korea, respectively. Both species are redescribed based on live observations and protargol impregnation. Cells of Euplotes encysticus are asymmetrically oval, $63-79{\times}41-61{\mu}m$ in vivo and capable of encystment. The cells have 31-36 adoral zone of membranelles(AZM), 9 fronto-ventral cirri (FVC), 5 transverse cirri (TC), 2-3 caudal cirri (CC), 2 marginal cirri (MC), 7 dorsal kineties (DK), and 19-22 dorsal cilia in middle DK. The cells of Euplotes rariseta has a small ovoid form and are $32-44{\times}23-35{\mu}m$ in vivo, 18-22 AZM, 10 FVC, 5 TC, 2 CC, 1 MC and 6 DK.

• Journal of Species Research
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• v.12 no.4
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• pp.368-373
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• 2023

The genus Acymatopus Takagi is reported for the first time from Korean fauna along with two nominate species, A. minor Takagi, 1965 and A. takeishii Masunaga, Saigusa & Yang, 2005. This genus belonging to the subfamily Hydrophorinae in the family Dolichopodidae. It comprised of only six species in the world and distributed only in Japan and China thus far. The genus is diagnosed by a metallic bluish-green body with thick gray tomentum, lacking black and white markings of mesonotum, 2 pairs of long marginal setae at scutellum and male's dorsally slightly curved fore tarsomere 1. Both adults and larvae of this genus are known to be found on rugged and rocky marine shores of the tidal zone. The authors found the first recorded species in the west seaside of Korea, where many barnacles inhabit. The descriptions and illustrations of external features including male genitalia of newly recorded species are provided in this paper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.695-700
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• 2011

Age, growth, and maturity of Trichiurus lepturus were estimated based on right-handed sagittal otoliths belonging to 1,031 fish collected from January to December 2007 in the East China Sea. The outer margins of the otolith were examined and showed that an opaque zone was formed once per year. Marginal increments in otoliths formed as annual rings between June and August, at the beginning of the spawning season. Fish growth was expressed by the von Bertalanffy growth equation, as follows: $L_t=494.0$ ($1-e^{-0.2453(t+-0.4822)}$) for females and $L_t=330.4$ ($1-e^{-0.4292(t+0.7513)}$) for males, where $L_t$ is the total length in mm and t is age in years. The growth rates of males and females were significantly different (P<0.05).The age composition ranged mostly between ages 2 and 4, and the oldest individuals were 4 years old in males and 6 years old in females. Finally, the age composition of largehead hairtail was compared with data from the 1970s and is discussed in the context of environmental changes.

• Journal of the Korean earth science society
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• v.29 no.6
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• pp.454-465
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• 2008

Benthic foraminiferal assemblage and AMS radiocarbon dating of core sediments from the northern shelf of the East China Sea were analyzed in order to understand the paleoenvironment and sedimentary environmental changes around the Korean marginal seas since the last glacial maximum (LGM). The core sediments, containing continuous records of the last 16,000 years, reveal a series of well-defined vertical changes in number of species (S), P/T ratio and species diversity (H) as well as foraminiferal assemblage. Such down-core variations display a sharp change at a core depth of approximately 240 cm, which corresponds to ca. 10,000 year B.P. The sediments of the lower part of the core (240${\sim}$560 cm, Zone I), including the well-developed tide-influenced sedimentary structures, are characterized by high abundances of Ammonia beccarii and Elphidium clavatum (s.l.) and low values in number of species, P/T ratio and diversity. These tide-influenced signatures and foraminiferal assemblage characters suggest that the sediments of Zone I were deposited in a coastal environment (water depths of 20${\sim}$30 m) such as tidal estuary with an influence of the paleo-rivers (e.g., old-Huanghe and Yangtze rivers) during the early phase of the sea-level rise (ca. 16,000 to 10,000 years) since the LGM. In contrast, the upper core sediments (0${\sim}$240 cm, Zone II) are characterized by abundant Eilohedra nipponica and Bolivina robusta with a minor contribution of A. ketienziensis angulata and B. marginata. and high values in number of species, P/T ratio and diversity. Based on relative abundance of these assemblage, Zone II can be divided into two subzones (IIa and IIb). Zone IIa is interpreted to be deposited under the inner-to-middle shelf environment during the marine transgression in the early Holocene (after ca. 9,000 yr B.P.) when sea level rapidly increased. The sediments of zone IIb most likely deposited after 6,000 yr B.P. under the outer shelf environment (80${\sim}$100 m water depth), which is similar to modem depositional environments. The muddy sediments of zone IIb were probably transported from the old-Huanghe and Yangtze Rivers during the late Holocene. We suggest that the present-day oceanographic conditions over the Yellow and the East China Seas have been established after ca. 7,000${\sim}$6,000 yr B.P. when the Kuroshio Current began to influence this area.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.23-25
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• 2008

Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.

• Animal Systematics, Evolution and Diversity
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• no.nspc5
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• pp.71-79
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• 2005

Two hypotrichous ciliates inhabiting the representative terrestrial habitats of Jindo Island, Holostichides chardezi Foissner, 1987 and Rigidocortex octonucleatus (Foissner, 1988) are found from Jindo Island. These two species are newly recorded from Korea. The description was based on the observation of living specimens, protargol impregnated specimens and biometric analysis. The morphological variations among the populations of these species were investigated with morphometry. The diagnostic characteristics of these species are as follows: Holostichides chardezi : elongate body flexible and twisted, yellowish subpellicular granules scattered entire cortex, adoral zone of membranelles covering about $28\%$ of body length, left and right rows of mid-ventral cirri paired, left row ended at buccal vertex and right row extending to center of body, no transverse cirri, both marginal rows of cirri not confluent at posterior end, 28-42 macronuclei and 1-5 micronuclei scattered entire body. 3 caudal cirri and 4 dorsal kineties. Rigidocortex octonucleatues: elongate-oval body rigid and not contractile, yellowish cytoplasmic crystals and fat globules densely packed, adoral zone of membranelles covering about $40\%$ of body length, 5 transverse cirri, both marginal rows of cirri not confluent at posterior end, 8 macronuclei longitudinally arranged in median of cell, 3 caudal cirri and 7-10 fragmented dorsal kineties.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.559-564
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• 1997

The New Hebrides Basin is an inactive non back-arc basin located at the convergent boundary of the Pacific and Info-Australian plates. This basin was formed from 46 Ma to 60 Ma. The basin has two spreading episodes with rates of 34 mm/a for 42 to 47 Ma and 17 mm/a for 47 to 60 Ma. The sediments covered in the basin has uniform thickness of 0.65 sec. The age-depth correlation curve of the New Hebrides Basin can be represented by the following equation: $Depth(m)=2689+312\sqrt{Age}(Ma)$ The coefficient of 312 in this equation is close to that for major oceans, 350. This suggests that the cooling processes of the lithospheres in the New Hebrides Basin and major oceans are similar to each other. Free-air gravity anomalies of the basin varying from -22.3 mgal to +59.0 mgal. The mean value is +30.2 mgal higher than those of the normal oceans. Moderately large free-air gravity anomalies in the New Hebrides Basin are presumably owing to its location on a marginal swell along the New Hebrides Trench. It is generally observed that the ocean floor is very gently uplifted in a zone about 200 km oceanward of the trench axis. Positive free-air gravity anomalies amounting to $50{\sim}60$ mgal are usually observed on the crest of the swell. This topography is presumably by bending of the oceanic lithosphere so as to dynamically maintain nonisostatic states for some duration.

• Economic and Environmental Geology
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• v.32 no.3
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• pp.217-225
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• 1999

Nine cauldrons have been recognized in the PVD (Pusan- Taegu Volcano-tectonic Depression) zone covering an area of nearly 7,000 $km^{2}$. They form characteristic landscape features with various mountains in the southeastern Kyongsang basin. Economically important ore deposits are also developed either in the ring fracture zone or the central pluton within the resurgent cauldrons or in the marginal area of the PVD, suggesting that these cauldrons played a major role in the distribution of ore deposits in the southeastern Kyongsang basin. Furthermore, the cauldron subsidences were more frequent with the more felsic volcano-plutonic complex, possibly indicating that the amounts of water and volatile components also acted as a controlling factor to cause the caldera subsidence and to concentrate the ore-forming elements in economic concentrations. The review of the relationship and variations of ore mineralization and cauldron subsidence is rather sketchy, but it provides a skeleton to carry out more detailed and quantitative studies related to temporal and spatial relationships between each cauldron subsidence accompanying its own ore mineralization. In the southeastern Kyongsang basin, additional calderas and associated ore deposits undoubtedly can be discovered through future detailed studies. The concept that cauldron subsidence are an important control for the formation of ore deposits will appear to be vindicated.

• Economic and Environmental Geology
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• v.19 no.spc
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• pp.175-191
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• 1986

The Geodo granodiorite intruded into the Joseon Supergroup is fine-grained at the marginal part, and medium-grained and more leucocratic at the central part. The Quartz monzonite porphyry intruded inte Precambrian granite and Geodo granodiorite has abundant plagioclase phenocryst. The Imog granite intruded into the Yulri Group and the Joseon Supergroup is mediumgrained biotite granite with partly pinkish feldspar phenocryst. The K/Ar ages obtained from the biotite of the Geodo granodiorite and Imog granite are Early ($111{\pm}1{\sim}107{\pm}1$ Ma) and Late ($93{\pm}1{\sim}92{\pm}1$ Ma) Cretaceous, respectively. The K/Ar sericite age of the quartz-sericite zone of the lower Jangsan quartzite occuring in the western area gave much younger age (about 170 Ma) than that of the Jangsan quartzite, that might be reset due to the regional metamorphism of the Daebo orogeny. The granitic rocks of the area are felsic to mafic, metaluminous to peraluminous, calc-alkalic (alkali-lime index${\fallingdotseq}$ 57) and I-type (magnetite-series) based on the chemical data_ And they appear to have been fractionated at the order of Geodo granodiorite, Quartz monzonite porphyry and Imog granite. In terms of mineralogy, geochemistry and K/Ar biotite age, a rock suite of monzodiorite, quartz monzodiorite and quartz monzonite-granodiorite in the Geodo stock was fractionally differentiated from a magmatic body from its margin to inward.