• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.3
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• pp.55-66
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• 2020

Near-inertial waves (NIW) which are primarily generated by wind can contribute to vertical mixing in the ocean. The energetic NIW can be generated by typhoon due to its strong wind and preferable wind direction changes especially on the right-hand side of the typhoon. Here we investigate the generation and distribution of NIW using the output of a real-time ocean forecasting system. Five-year model outputs during 2013-2017 are analyzed with a focus on cases of energetic NIW generation by the passage of three typhoons (Halong, Goni, and Chaba) over the East Sea. Calculations of wind energy input (${\bar{W}}_I$), and horizontal kinetic energy in the mixed layer (${\bar{HKE}}_{MLD}$) reveal that the spatial distribution of ${\bar{HKE}}_{MLD}$, which is strengthened at the right-hand side of typhoon tracks, is closely related with ${\bar{W}}_I$. Horizontal kinetic energy in the deep layer (${\bar{HKE}}_{DEEP}$) shows patch-shaped distribution mainly located at the southern side of the East Sea. Spatial distribution of ${\bar{HKE}}_{DEEP}$ shows a close relationship with negative relative vorticity regions caused by warm eddies in the upper layer. Monthly-mean ${\bar{HKE}}_{MLD}$ and ${\bar{HKE}}_{DEEP}$ during a typhoon passing over the East Sea shows about 2.5-5.7 times and 1.2-1.6 times larger values than those during summer with no typhoons, respectively. In addition, their magnitudes are respectively about 0.4-1.0 and 0.8-1.0 times from those during winter, suggesting that the typhoon-induced NIW can provide a significant energy to enhance vertical mixing at both the mixed and deep layers during summer.

• Journal of the Korean Society for information Management
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• v.39 no.2
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• pp.233-254
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• 2022

Link reduction algorithms such as pathfinder network are the widely used methods to overcome problems with the visualization of weighted networks for knowledge domain analysis. This study proposed NetRSQ, an indicator to measure the goodness of fit of a link reduction algorithm for the network visualization. NetRSQ is developed to calculate the fitness of a network based on the rank correlation between the path length and the degree of association between entities. The validity of NetRSQ was investigated with data from previous research which qualitatively evaluated several network generation algorithms. As the primary test result, the higher degree of NetRSQ appeared in the network with better intellectual structures in the quality evaluation of networks built by various methods. The performance of 4 link reduction algorithms was tested in 40 datasets from various domains and compared with NetRSQ. The test shows that there is no specific link reduction algorithm that performs better over others in all cases. Therefore, the NetRSQ can be a useful tool as a basis of reliability to select the most fitting algorithm for the network visualization of intellectual structures.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.84-99
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• 2021

As the micro-mobility market grows, the demand for route guidance, that includes uphill information as well, is increasing. Since the climbing angle depends on the electric motor uesed, it is necessary to establish an uphill road DB according to the threshold standard. Although road alignment information is a very important element in the basic information of the roads, there is no information currently on the longitudinal slope in the road digital map. The High Definition(HD) map which is being built as a preparation for the era of autonomous vehicles has the altitude value, unlike the existing standard node link system. However, the HD map is very insufficient because it has the altitude value only for some sections of the road network. This paper, hence, intends to propose a method to generate the road longitudinal slope using currently available data. We developed a method of computing the longitudinal slope by combining the digital elevation model and the standard link system. After creating an altitude at the road link point divided by 4m based on the Seoul road network, we calculated individual slope per unit distance of the road. After designating a representative slope for each road link, we have extracted the very steep road that cannot be climbed with personal mobility and the slippery roads that cannot be used during heavy snowfall. We additionally described errors in the altitude values due to surrounding terrain and the issues related to the slope calculation method. In the future, we expect that the road longitudinal slope information will be used as basic data that can be used for various convergence analyses.

• Journal of Life Science
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• v.33 no.4
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• pp.349-356
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• 2023

Gout, a chronic inflammatory arthritic disease, is characterized by hyperuricemia. Gout can be induced by an inflammatory response to monosodium urate (MSU) crystals mediated by pro-inflammatory cytokine release following activation of the NOD-like receptor protein 3 (NLRP3) inflammasome. Many sulfur-containing phytochemical compounds in garlic (Allium sativum L.) are considered active ingredients because of their potential pharmacological benefits for various diseases, but their efficacy in NLRP3 inflammasome activation-mediated gout has not been demonstrated. In this study, we investigated whether diallyl disulfide (DADS) and diallyl trisulfide (DATS), representative garlic-derived sulfur compounds, have an inhibitory effect on MSU-induced NLRP3 inflammasome activation. Our results showed that under non-cytotoxic conditions, DADS and DATS significantly blocked nitric oxide production and interleukin (IL)-1β release in response to MSU in lipopolysaccharide (LPS)-primed RAW 264.7 macrophages. DADS and DATS also attenuated enhanced expression of NLRP3 and its adapter protein, apoptosis-associated speck-like protein, which was associated with downregulation of and caspase-1 p20 and IL-1β expression, suggesting that MSU-induced LRP3 inflammasome activation was counteracted by DADS and DATS. Furthermore, DADS and DATS blocked oxidative stress, an upstream event for NLRP3 inflammasome activation, as evidenced by the fact that they scavenged reactive oxygen species (ROS) production. Taken together, our findings demonstrate that DADS and DATS suppressed NLRP3 inflammasome activation by inhibiting the ROS/NLRP3 pathway and that they have potential as treatments for NLRP3-dependent gouty arthritis.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.466-477
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• 2018

In this study, the anti-inflammatory activities of the extracts of different parts of Hovenia dulcis such as leaves, stems, and roots were investigated. Among them, the roots extract (RE) showed the most potent suppressive effect against pro-inflammatory mediators in LPS-stimulated mouse macrophage cells. RE induced dose-dependent reduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and concomitantly reduced the production of NO and $PGE_2$. Additionally, pre-treatment with RE significantly suppressed the production of inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6, as well as mRNA levels. Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-kB) were also strongly attenuated by RE in RAW264.7 cell. Furthermore, RE induced HO-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and increase HO-1 activity in RAW264.7 macrophages. Therefore, these results indicate that RE strongly inhibits LPS-induced inflammatory responses by blocking NF-kB activation, inhibiting MAPKs phosphorylation, and enhancing HO-1 expression in macrophages, suggesting that RE of H. dulicis and a major component, 27-O-protocatechuoylbetulinic acid could be applied as a valuable natural anti-inflammatory material.

• Journal of Life Science
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• v.31 no.12
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• pp.1110-1119
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• 2021

The purpose of this study was to investigate whether the inflammatory response in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages could be promoted by particulate matter 2.5 (PM_2.5) stimulation. To this end, the levels of inflammatory parameters, reactive oxygen species (ROS) and inflammation-regulating genes were investigated in RAW 264.7 cells treated with PM_2.5 in the presence or absence of LPS. Our results showed that the production levels of pro-inflammatory mediators (nitric oxide and prostaglandin E₂) and cytokines (interleukin-6 and -1β) were significantly increased by PM_2.5 stimulation in LPS-treated RAW 264.7 cells, which was correlated with increased expression genes involved in their production. In addition, when LPS-treated RAW 264.7 cells were exposed to PM_2.5, nuclear factor-kappaB (NF-κB) expression was further increased in the nucleus, and the expression of inhibitor of NF-κB as well as NF-κB in the cytoplasm was decreased. These results suggest that the co-treatment of PM_2.5 and LPS further increases the activation of the NF-κB signaling pathway compared to each treatment alone, thereby contributing to the promotion of transcriptional activity of inflammatory genes. Furthermore, although the generation of ROS was greatly increased by PM_2.5 in LPS-treated RAW 264.7 cells, the NF-κB inhibitor did not reduce the generation of ROS. In addition, when the generation of ROS was artificially suppressed, the production of inflammatory mediators and the activation of NF-κB were both abolished. Therefore, our results suggest that the increase in the NF-κB-mediated inflammatory response induced by PM_2.5 in LPS-treated RAW 264.7 macrophages was a ROS generation-dependent phenomenon.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1450-1457
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• 2015

The anti-inflammatory effect of ethanol extracts from Hizikia fusiformis fermented with and without lactic acid bacteria was compared in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophages. The fermentation was done using Weissella sp. SH-1 and Lactobacillus casei in a mixture of glucose and lactate source at $30^{\circ}C$ for 30 days. As a result, we confirmed that the fermentation of H. fusiformis with lactic acid bacteria inhibited LPS-stimulated nitric oxide (NO) production and the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, interleukin (IL)-6, tumor necrosis factor ${\alpha}$, and IL-$1{\beta}$ as important inflammatory factors. During a comparison analysis, we found that L. casei fermented groups significantly suppressed NO production by regulating iNOS and COX-2 expression. Also, the effective suppression of pro-inflammatory cytokine and LPS-induced activation of mitogen- activated protein kinase indicated that the fermentation using Weissella sp. SH-1 and L. casei may provide an increment towards the extraction of active components, which are effective anti-inflammatory agents.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.179-183
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• 2010

This study is to characterize the postulated anti-inflammatory effect of the hot water extracts from the Phellinus baumii. RAW264.7, macrophage cell line, was activated by lipopolysaccharide (LPS) and, further, treated with Phellinus baumii's aqueous extract. When the cultured macrophage cells were treated with LPS, they show typical signs of endoplasmic reticulum stress (ERS) and an increment in secretion of inflammatory cytokine compared to the non-treated control: The expression of glucose-regulated protein78 (Grp78), Grp94, and C/EBP homologous protein/GADD 153 (CHOP) increased along with augmented secretion of interlukin-6. Cellular nitric oxide content also significantly went up in comparison to the non-LPS treatment. When the LPS-treated RAW264.7 was treated with the aqueous Phellinus baumii extracts, however, the expression of ERS markers markedly reduced and the release of nitric oxide declined. Also, the expression of induced nitric oxide synthase (iNOS) notably diminished similarly as the NO content. In conclusion, this study strongly indicated that aqueous Phellinus baumii extract can be utilized directly as anti-inflammation agent and serves as a source of functional ingredient to lessen the inflammation.

• Journal of agriculture & life science
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• v.50 no.2
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• pp.139-150
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• 2016

Few studies have been reported that horse-bone extract(HBE) can prevent and treatment of bone diseases. However, HBE' therapeutic activities are still not fully understood. This study determined whether HBE up-regulates hemeoxygenase 1(HO-1) and this mediates its anti-inflammatory effect in murine macrophages.Nitric oxide(NO) assay, MTT assay and DPPH assay were performed. In addition, Western blotting and real time PCR were used to determine protein expression, and gene expression, respectively. HBE significantly inhibited NO production without observable cytotoxicity. In addition, HBE attenuated inducible nitric oxide synthase (iNOS), cyclooxygenase-2(COX-2) and phospho (p)-ERK protein expressions in LPS(0.1㎍/ml) stimulated RAW264.7 cells. On the other hand, HBE alone up-regulated HO-1 and Nrf-2 expressions, which mediated HBE's anti-inflammatory effect in RAW264.7 cells. Finally, HBE up-regulated HO-1 and impaired ERK1/2 signaling pathways, and thus it may provide protection against cellular oxidation and inflammation.

• Journal of Life Science
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• v.27 no.5
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• pp.509-516
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• 2017

Perilla frutescens (L.) Britton var. sprouts (PFS) is a plant of the labiatae family. The purpose of this work was to assess the preventive effects of PFS ethanolic extracts (PFSEs) on cytokine-induced ${\beta}$-cell damage. Cytokines, which are released by the infiltration of inflammatory cells around the pancreatic islets, are involved in the pathogenesis of type 1 diabetes mellitus. The combination of interleukin-$1{\beta}$ (IL-1), interferon-${\gamma}$ (IFN-${\gamma}$), and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) induced formation of reactive oxygen species (ROS). Accumulation of intracellular ROS led to ${\beta}$-cell dysfunction and apoptosis. PFSEs possess antioxidant activity and thus lead to downregulation of ROS generation. Cytokines decrease cell viability, stimulate the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and induce the production of nitric oxide (NO). PFSEs prevented cytokine-induced cell viability in a dose-dependent manner. Incubation with PFSE resulted in significant reduction in cytokine-induced NO production that correlated with reduced levels of the iNOS and COX-2 protein expression. Furthermore, PFSE significantly decreased the activation of nuclear factor ${\kappa}B$ (NF-${\kappa}B$) by inhibition of $I{\kappa}B{\alpha}$ phosphorylation in RINm5F cells. In summary, our results suggest that the protective effects of PFSE might serve to counteract cytokine-induced ${\beta}$-cell destruction. Findings indicate that consumption of Perilla frutescens (L.) Britton var. sprouts alleviates hyperglycemia-mediated oxidative stress and pro-inflammatory cytokine-induced ${\beta}$-cell damage and thus has beneficial anti-diabetic effects.