• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.358-365
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• 2000

To evaluate the influences of stocking and removal of silver carp on plankton communities and physicochemical parameters, fish biomanipulation was conducted in six enclosures constructed on the coast of a hypertrophic lake during the summer of 1997. Of these, three enclosures were established for the fish-stocking experiment; one fishless enclosure used as a control and two enclosures with high and low densities of fish. The other three enclosures for the fish-removal experiment were prepared in an entirely converse process compared to that for fish stocking. The results of randomized intervention analysis (${\alpha}=0.05$) showed significant changes in several physicochemical parameters and plankton communities after fish stocking and removal. Fish stocking decreased water transparency, DO, pH and chi-a (> $40\;{\mu}m$), while increasing the concentration of nitrogen and chi-a (<$2\;{\mu}m$). However, water transparency did not increase by fish removal. Small plankton communities, such as picocyanobacteria, eukaryotic picoplankton and ciliates (<$2\;{\mu}m$) showed significant reciprocal changes after both fish treatments: increase by the presence of fish and decrease by the absence of fish. No count of large sized phytoplankton and zooplankton showed significant change in the presence of fish, while large zooplankton, Diaphanosoma, Cyclopida and nauplii were significantly increased by fish removal. Although the frequent heavy-winds and endless supply of phosphorus from the lake sediment strongly disturbed the fish behavior and enclosure management, the stocking and removal of silver carp showed an obvious reciprocal influences on plankton communities and its physico-chemical parameters in a shallow-hypertrophic lake.

• Biomedical Science Letters
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• v.3 no.2
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• pp.83-88
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• 1997

In septic patients, disseminated intravascula. coagulation (DIC) occurs frequently and is a pathologic condition associated with a variety of critical illness. DIC may complicate the already complex clinical situations and contribute to the high mortality. Nevertheless, its pathogenic mechanisms are not completely elucidated. Present study was prospectively designed to understand the pathogenetic mechanisms involved in the development of DIC. 15 rats were subjected to study and according to the aim, they were divided into three groups： group I, control (not treated-endotoxin, n=5)； group II (12 hours after endotoxin injection, n=5)； group III (24 hours after endotoxin injection, n=5). Experimental DIC was induced in rats by a bolus injection of endotoxin (1mg/kg, E. coli serotype 055:B5). Blood was collected by direct puncture of the heart. Platelet count, fibrinogen and plasminogen concentration, antithrombin III, D-dimer and complement components (C3 and C4) were measured in all subjects. In group II and III, there were apparent signs of DIC, including thrombocytopenia, decreased fibrinogen (but increase in group III), reduced C3 and antithrombin III, and elevated D-dimer. These data indicated that endotoxin might induce the activation of several pathways such as coagulation, fibrinolytic and complement cascade, causing DIC and subsequent multiple organ failures. Ultimately, the increased knowledge of the various pathogenetic mechanisms of coagulation activation and fibrinolysis in endotoxin-induced DIC may have prophylactic or therapeutic implications.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5199-5205
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• 2013

Background/Aim: The Hippo signaling pathway is a newly discovered and conserved signaling cascade, which regulates organ size control by governing cell proliferation and apoptosis. This study aimed to investigate its effects in human gastric cancer. Methods: Tumor tissues (n=60), adjacent non-tumor tissues (n=60) and normal tissues (n=60) were obtained from the same patients with primary gastric cancer (GC). In addition, 70 samples of chronic atrophic gastritis (CAG) tissues were obtained from patients with intestinal metaplasia (IM) by endoscopic biopsy. Hippo signaling molecules, including Mst1, Lats1, YAP1, TAZ, TEAD1, Oct4 and CDX2, were determined by quantitative polymerase chain reaction (qPCR). Protein expression of Mst1, Lats1, YAP1, TEAD1 and CDX2 was assessed by immunohistochemistry and Western blotting. Results: Mst1, Lats1 and Oct4 mRNA expression showed an increasing tendency from GC tissues to normal gastric tissues, while the mRNA expression of YAP1, TAZ and TEAD1 was up-regulated (all P<0.01). Mst1 and Lats1 protein expression presented a similar trend with their mRNA expression. In addition, YAP1 and TEAD1 protein expression in GC was significantly higher than in the other groups (all P<0.01). CDX2 mRNA and protein expression in the CAG group were higher than in the other groups (all P<0.01). In GC, mRNA expression of Mst1, Lats1, Oct4, YAP1, TAZ, TEAD1 and CDX2 had a close correlation with lymphatic metastasis and tumor TNM stage (all P<0.01). Furthermore, protein expression of Mst1, Lats1, YAP1, TAZ, TEAD1 and CDX2 had a close correlation between each other (P<0.05). Conclusion: The Hippo signaling pathway is involved in the development, progression and metastasis of human gastric cancer. Therefore, manipulation of Hippo signaling molecules may be a potential therapeutic strategy for gastric cancer.

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.120-122
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• 2007

All living organisms use numerous signal-transduction pathways to sense and respond to their environments and thereby survive and proliferate in a range of biological niches. Molecular dissection of these signalling networks has increased our understanding of these communication processes and provides a platform for therapeutic intervention when these pathways malfunction in disease states, including infection. Owing to the expanding availability of sequenced genomes, a wealth of genetic and molecular tools and the conservation of signalling networks, members of the fungal kingdom serve as excellent model systems for more complex, multicellular organisms. Here, we employed Cryptococcus neoformans as a model system to understand how fungal-signalling circuits operate at the molecular level to sense and respond to a plethora of environmental stresses, including osmoticshock, UV, high temperature, oxidative stress and toxic drugs/metabolites. The stress-activated p38/Hog1 MAPK pathway is structurally conserved in many organisms as diverse as yeast and mammals, but its regulation is uniquely specialized in a majority of clinical Cryptococcus neoformans serotype A and D strains to control differentiation and virulence factor regulation. C. neoformans Hog1 MAPK is controlled by Pbs2 MAPK kinase (MAPKK). The Pbs2-Hog1 MAPK cascade is controlled by the fungal "two-component" system that is composed of a response regulator, Ssk1, and multiple sensor kinases, including two-component.like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. We also identified and characterized the Ssk2 MAPKKK upstream of the MAPKK Pbs2 and the MAPK Hog1 in C. neoformans. The SSK2 gene was identified as a potential component responsible for differential Hog1 regulation between the serotype D sibling f1 strains B3501 and B3502 through comparative analysis of their meiotic map with the meiotic segregation of Hog1-dependent sensitivity to the fungicide fludioxonil. Ssk2 is the only polymorphic component in the Hog1 MAPK module, including two coding sequence changes between the SSK2 alleles in B3501 and B3502 strains. To further support this finding, the SSK2 allele exchange completely swapped Hog1-related phenotypes between B3501 and B3502 strains. In the serotype A strain H99, disruption of the SSK2 gene dramatically enhanced capsule biosynthesis and mating efficiency, similar to pbs2 and hog1 mutations. Furthermore, ssk2, pbs2, and hog1 mutants are all hypersensitive to a variety of stresses and completely resistant to fludioxonil. Taken together, these findings indicate that Ssk2 is the critical interface protein connecting the two-component system and the Pbs2-Hog1 pathway in C. neoformans.

• KSBB Journal
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• v.24 no.5
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• pp.425-431
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• 2009

Hepatocyte growth factor (HGF) and its receptor play an important role in the formation and progression of glioma. In this study, I investigated the ability of HGF to recover of the PSA siRNA-suppressed cell proliferation, migration and invasion in U-251-MG cells. PSA siRNA-transfected U-251-MG cells showed the reduction of the proliferation, migration and invasion with compared to control. Treatment of HGF on the PSA siRNA-transfected U-251-MG cells recovered the ability of proliferation, migration and invasion. These data suggest that PSA and HGF may use unique and parallel signaling cascade leading to the proliferative, migrative and invasive phenotype of U-251-MG cells. I also showed that PSA cooperated with HGF to a migrative and invasive phenotype via the increased secretion of matrix metalloproteinase-2 (MMP-2) and MMP-9.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.39-45
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• 2016

BACKGROUND: This study aimed to evaluate the combined effects of three components (NPK) of chemical fertilizers with basal application of compost on soil organisms.METHODS AND RESULTS: The soil was treated with five treatments continuously for 15 years: control, PK, NK, NP and NPK. The application of N increased plant growth or biomass, and enhanced organic matter content in the soils. Levels of microbial phospholipid fatty acids (PLFAs) in the soils did not show marked differences among the soils treated with different treatments. However, the principal component analysis showed the changes in the structure of the microbial community in the soil, depending on treatments added. Nitrogen application caused a decrease of pH and an increase of EC in the soils, and these environmental stresses appeared to offset the promoting effect of increased organic matter content on microbial abundance. The abundance of bacterivorous nematodes was the highest in the soils after treating NPK; however, the abundance of fungivorous nematodes was unaffected. There was no significant correlation between the abundances of microbial groups and their feeders. Organic matter content was significantly correlated with the abundance of nematodes in the soils.CONCLUSION: Our results showed that chemical fertilizers affect the soil food chains through both biotic and abiotic factors, and a trophic cascade in the soils may not occur in response to long-term fertilization.

• Journal of Life Science
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• v.25 no.5
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• pp.585-593
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• 2015

Stress fiber (SF) alteration is mediated by cellular receptors, which, upon interaction with the extracellular counterpart, signal to the actin cytoskeleton for remodeling. This association is mediated by a variety of scaffold and signaling factors, which control the mechanical and signaling activities of the interaction site. The heterotrimeric transmembrane lymphotoxin α1β2 (LTα1β2), a member of the tumor necrosis factor (TNF) family of cytokines, including soluble homotrimeric lymphotoxin (LT α), plays an important role in lymphoid tissue architecture. Ligation between LTα1β2 and the lymphotoxin β receptor (LTβR) activates signal-cascade in fibroblastic reticular cells (FRCs). We found LTβR stimulation using an agonistic anti-LTβR antibody alone or combined with LTα or TNFα induced changes in the actin and plasticity of cells. To clarify the involvement of myosin underlying the alteration, we analyzed the effect of myosin light chain kinase (MLCK) with an MLCK inhibitor (ML7), the phosphorylation level of myosin light chains (MLC), and the level of phospho-myosin phosphatase target subunit 1 (MYPT1) after treatment with an agonistic anti-LTβR antibody for cytoskeleton reorganization in FRCs. The inhibition of MLCK activity induced changes in the actin cytoskeleton organization and cell morphology in FRC. In addition, we showed the phosphorylation of MLC and MYPT1 was reduced by LTβR stimulation in cells. A DNA chip revealed the LTβR stimulation of FRC down-regulated transcripts of myosin and actin components. Collectively, these results suggest LTβR stimulation is linked to myosin regarding SF alteration in FRC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.155-162
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• 2007

The purpose of this study is to investigate the anti type I allergic effects and mechanisms of the phyto extract mixture (PEM381) which contains Camellia sinensis (leaf), Psidium guajava (leaf), and Rosa hybrida (flower). PEM381 was tested for its inhibitory effects on arachidonic acid cascade related enzymes (5-lipoxygenase and cyclooxygenase), the mast cell mediated allergic reaction and passive cutaneous anaphylaxis. $IC_{50}$ value of PEM381 against 5-lipoxygenase was $14.11{\pm}0.51ppm$ while that of positive control (nordihy-droguaiaretic acid) was $0.54{\pm}0.08ppm$. PEM381 also exhibited considerable selective inhibition of cyclooxygenase-2. PEM381 could inhibit both degranulation and histamine release in a dose dependent manner from rat peritoneal mast cells activated by compound 48/80. In addition, oral administration of PEM381 showed an inhibitory effect on passive cutaneous anaphylaxis reaction activated by anti-dinitrophenyl IgE antibody in mice. These results suggest that PEM381 may be useful for the prevention and treatment of type Ⅰ allergy related diseases.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.9
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• pp.361-368
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• 2014

The LPR(License plate recognition) system has been developed to efficient control for complex traffic environment and currently be used in many places. However, because of light, noise, background changes, environmental changes, damaged plate, it only works limited environment, so it is difficult to use in real-time. This paper presents a heuristic segmentation algorithm for robust to noise and illumination changes and introduce a real-time license plate recognition system using it. In first step, We detect the plate utilized Haar-like feature and Adaboost. This method is possible to rapid detection used integral image and cascade structure. Second step, we determine the type of license plate with adaptive histogram equalization, bilateral filtering for denoise and segment accurate character based on adaptive threshold, pixel projection and associated with the prior knowledge. The last step is character recognition that used histogram of oriented gradients (HOG) and multi-layer perceptron(MLP) for number recognition and support vector machine(SVM) for number and Korean character classifier respectively. The experimental results show license plate detection rate of 94.29%, license plate false alarm rate of 2.94%. In character segmentation method, character hit rate is 97.23% and character false alarm rate is 1.37%. And in character recognition, the average character recognition rate is 98.38%. Total average running time in our proposed method is 140ms. It is possible to be real-time system with efficiency and robustness.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.1
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• pp.32-48
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• 2018

The mechanisms of $CH_4$ uptake into and release from the ocean are not well understood due mainly to complexity of the biogeochemical cycle and to lack of regional-scale and/or process-scale observations in the marine boundary layers. Without complete understanding of oceanic mechanisms to control the carbon balance and cycles on a various spatial and temporal scales, however, it is difficult to predict future perturbation of oceanic carbon levels and its influence on the global and regional climates. High frequency, high precision continuous measurements for carbon isotopic compositions from dissolved $CH_4$ in the surface ocean and marine atmosphere can provide additional information about the flux pathways and production/consumption processes occurring in the boundary of two large reservoirs. This paper introduces recent advances on optical instruments for real time $CH_4$ isotope analysis to diagnose potential applications for in situ, continuous measurements of carbon isotopic composition of dissolved $CH_4$. Commercially available, three laser absorption spectrometers - quantum cascade laser spectroscopy (QCLAS), off-axis integrated cavity output spectrometer (OA-ICOS), and cavity ring-down spectrometer (CRDS) are discussed in comparison with the conventional isotope ratio mass spectrometry (IRMS). Details of functioning and performance of a CRDS isotope instrument for atmospheric ${\delta}^{13}C-CH_4$ are also given, showing its capability to detect localized methane emission sources.