• Natural Product Sciences
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• v.18 no.1
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• pp.60-66
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• 2012

Human skin is the first line of defense for the protection of the internal organs of the body from different stimuli. Ultraviolet B (UVB) irradiation induces skin damage and inflammation through the secretion of various cytokines, which are immune regulators produced by cells. To prevent the initiation of skin inflammation, keratinocytes that have been irreversibly damaged by radiation must be removed through the apoptotic mechanism. Ixeris dentata (family: Asteraceae) is a perennial medicinal herb indigenous to Korea. It has been used in Korea, China, and Japan to treat in digestion, pneumonia, diabetes, hepatitis, and tumors. To gain insight into the anti-inflammatory effects of I. dentata, we examined its influence on UVB-induced pro-inflammatory cytokine production in human keratinocytes (HaCaT cells), by observing cells that were stimulated with UVB in the presence or absence of I. dentata. In the present study, pro-inflammatory cytokine production was determined by performing enzyme-linked immunosorbent assay, reverse transcription polymerase chain reaction, and western blot analysis to measure the activation of mitogen-activated protein kinase (MAPKs). I. dentata inhibited UVBinduced production of the pro-inflammatory cytokine interleukin (IL)-6 in a dose-dependent manner. Further, I. dentata inhibited the UVB-induced expression of cyclooxygenase (COX)-2. Furthermore, I. dentata inhibited the phosphorylation of c-Jun NH2-terminal kinase and p38 MAPKs, suggesting that it inhibits the secretion of the pro-inflammatory cytokines IL-6 and IL-8, and COX-2 expression, by blocking MAPK phosphorylation. These results suggest that I. dentate can potentially protect against UVB-induced skin inflammation.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.300-308
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• 2000

The Fibroblast growth factors(FGFs) plays an important role in the control of osteogenesis during skeletal development. Especially, FGF-2 is a potent mesodermal inducer during embryogenesis and FGF receptors (FGFRs) messages are strongly expressed in developing bones. In this study, we investigated the effect of bFGF on osteopontin(OPN) gene expression in ST-2 cells and tried to elucidate the mechanism of its stimulatory effects. The obtain results were as follows; The treatment of bFGF(1ng/ml) upregulates OPN, fibronectin mRNA levels and downregulates type I collagen mRNA levels. But, there was no remarkable difference in alkaline phosphatase mRNA levels between two groups. The OPN gene expression increased in a dose-dependent manner up to 10ng/ml and OPN gene began to occur at around 3h with continuous increase up to 24h then decreased to basal level at 48h. 30 minutues pretreatment with cycloheximide (500ng/ml), a protein synthesis inhibitor, prior to addition bFGF resulted in blocking bFGF induced OPN expression. These results suggest that bFGF increased the level of OPN mRNA in a dose and time-dependent manner via the synthesis of certain transcriptional regulatory proteins.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.129-136
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• 2020

A Cut Out Switch (COS) is used for line protection and pole transformer protection in power systems. The COS used to protect the pole transformer is installed on the power side of the pole transformer to protect the electric equipment from fault currents. The COS is composed largely of a body and a fuse holder, and when the fault current is energized, the element of the fuse link in the fuse holder is melted to block the fault current. The arc generated when the COS fuse link is blown causes fire and noise, causing discomfort to residents in the surrounding area, and the arc flame can cause secondary damage to the peripheral device. In this study, a current-limiting COS fuse with improved overcurrent blocking performance rather than explosion type was developed to solve the arc and noise problems during COS operation. The overcurrent breaking performance of the current-limiting COS improves the reliability by developing a striker and COS fuse bracket. In addition, this study aimed to verify the performance of the developed current-limiting COS fuse through a test at an authorized institution.

• Journal of Life Science
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• v.27 no.11
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• pp.1269-1275
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• 2017

Tenebrio molitor samples were investigated as novel biomaterials and sources of food in several recent studies. However, the insects' effects on hair growth were not sufficiently researched. To develop novel and natural materials for preventing alopecia and promoting hair growth, this study investigated the antioxidant activities and hair-growth promotion effects of TMEs. To determine the antioxidant activities, the TMEs' DPPH radical- and nitrite-scavenging activities were examined. To determine hair-growth promotion effects, proliferations of human dermal papilla cells (DPCs) and the murine fibroblast cell line NIH3T3 were evaluated by using an MTS assay. In addition, estimations were made for cell viabilities against cell death induced by dihydrotesterone (DHT) in DPCs and inhibitory effects against potassium channel blocking induced by tolbutamide (TBM) in NIH3T3 cells. The DPPH radical scavenging activity was 81.17%, and the nitrite scavenging activity was 43.69%; the activities were similar to the activities of blueberry extracts. Moreover, the TMEs promoted the proliferation of human DPCs and NIH3T3 cells, which were concentrated dependently. The TMEs prevented not only DHT-induced DPC cytotoxicity but also TBM's action as a potassium channel blocker in NIH3T3 cells. The results suggested that TME could be used as a functional therapeutic alopecia reagent, to prevent hair loss and to promote hair growth.

• Molecules and Cells
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• v.40 no.2
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• pp.109-116
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• 2017

Soybean agglutinin (SBA) is an anti-nutritional factor of soybean, affecting cell proliferation and inducing cytotoxicity. Integrins are transmembrane receptors, mediating a variety of cell biological processes. This research aims to study the effects of SBA on cell proliferation and cell cycle progression of the intestinal epithelial cell line from piglets (IPEC-J2), to identify the integrin subunits especially expressed in IPEC-J2s, and to analyze the functions of these integrins on IPEC-J2 cell cycle progression and SBA-induced IPEC-J2 cell cycle alteration. The results showed that SBA lowered cell proliferation rate as the cell cycle progression from G0/G1 to S phase (P < 0.05) was inhibited. Moreover, SBA lowered mRNA expression of cell cycle-related gene CDK4, Cyclin E and Cyclin D1 (P < 0.05). We successfully identified integrins ${\alpha}2$, ${\alpha}3$, ${\alpha}6$, ${\beta}1$, and ${\beta}4$ in IPEC-J2s. These five subunits were crucial to maintain normal cell proliferation and cell cycle progression in IPEC-J2s. Restrain of either these five subunits by their inhibitors, lowered cell proliferation rate, and arrested the cells at G0/G1 phase of cell cycle (P < 0.05). Further analysis indicated that integrin ${\alpha}2$, ${\alpha}6$, and ${\beta}1$ were involved in the blocking of G0/G1 phase induced by SBA. In conclusion, these results suggested that SBA lowered the IPEC-J2 cell proliferation rate through the perturbation of cell cycle progression. Furthermore, integrins were important for IPEC-J2 cell cycle progression, and they were involved in the process of SBA-induced cell cycle progression alteration, which provide a basis for further revealing SBA anti-proliferation and anti-nutritional mechanism.

• Journal of Animal Science and Technology
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• v.64 no.5
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• pp.922-936
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• 2022

5-Hydroxytryptamine (5-HT), a monoamine, as a local regulator in the mammary gland is a chemical signal produced by the mammary epithelium cell. In cows, studies have shown that 5-HT is associated with epithelial cell apoptosis during the degenerative phase of the mammary gland. However, studies in other tissues have shown that 5-HT can effectively promote cell viability. Whether 5-HT could have an effect on mammary cell viability in dairy cows is still unknown. The purpose of this study was to determine: (1) effect of 5-HT on the viability of bovine mammary epithelial cells and its related signaling pathways, (2) interaction between prolactin (PRL) and 5-HT on the cell viability. The bovine mammary alveolar cell-T (MAC-T) were cultured with different concentrations of 5-HT for 12, 24, 48 or 72 hours, and then were assayed using cell counting kit-8, polymerase chain reaction (PCR) and immunobloting. The results suggested that 20 μM 5-HT treatment for 12 or 24 h promote cell viability, which was mainly induced by the activation of 5-HT receptor (5-HTR) 1B and 4, because the increase caused by 5-HT vanished when 5-HTR 1B and 4 was blocked by SB224289 and SB204070. And protein expression of mammalian target of rapamycin (mTOR), eukaryotic translation elongation factor 2 (eEF2), janus kinase 2 (JAK2) and signal transducer and activator of transcription 5 (STAT5) were decreased after blocking 5-HT 1B and 4 receptors. When MAC-T cells were treated with 5-HT and PRL simultaneously for 24 h, both the cell viability and the level of mTOR protein were significantly higher than that cultured with 5-HT or PRL alone. In conclusion, our study suggested that 5-HT promotes the viability of MAC-T cells by 5-HTR 1B and/or 4. Furthermore, there is a reciprocal relationship between PRL and 5-HT.

• The Korea Journal of Herbology
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• v.32 no.2
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• pp.107-114
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• 2017

Objectives : Tribulus terrestris $Linn{\acute{e}}$ (Tribuli Fructus; TF) has been used to treat hypochondrium, agalactia, nebula, itching and vitiligo in traditional Korean medicine. In this study, we investigated the effects of TF 30% ethanol extract on inflammatory responses in IgE-stimulated RBL-2H3 mast cells. Methods : TF extract was prepared by 30% ethanol. RBL-2H3 cells, a rat mast cell line, were treated with TF extract at different concentrations for 1 hr and then stimulated with DNP-IgE/HSA for indicated times. Cell viability was measured by WST-1 assay. The expression of inflammatory cytokines (IL-4, IL-13 and $IFN-{\gamma}$) mRNA was determined by reverse transcriptase-PCR, and the phosphorylation of ERK1/2, p38 and JNK MAP kinases (MAPKs) was determined by Western blot. The nuclear expression of $NF-{\kappa}B$ p65 in the cells was detected by Western blot and immunocytochemistry, respectively. Results : The treatment of TF extract at 0.1 and $0.2mg/m{\ell}$ significantly decreased the expression of IL-4 and IL-13 mRNA in IgE-stimulated RBL-2H3 mast cells, while significantly increased the expression of $IFN-{\gamma}$ mRNA. TF extract treatment was also inhibited the phosphorylation of ERK1/2, p38 and JNK MAPKs in IgE-stimulated RBL-2H3 mast cells in a dose-dependent manner. In addition, TF extract significantly blocked the translocation of $NF-{\kappa}B$ p65 into the nuclear of cells after IgE stimulation. Conclusions : These results indicate that TF extract inhibits inflammatory response in IgE-stimulated mast cells through blocking MAPKs/$NF-{\kappa}B$ pathway. This suggests that TF extract has an anti-inflammatory activity in mast cell activation.

• Maritime Security
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• v.6 no.1
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• pp.1-35
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• 2023

The purpose of this study is to present the direction of development of our navy's response strategy through analysis at the ends, ways, and means level of the Chinese navy's offensive strategy for the West Sea. As a result of the analysis, at the ends level, the Chinese Navy's offensive strategy for the West Sea strategy is being linked to a grand strategy to protect maritime rights and achieve maritime power between the U.S. and China competition, at the ways level, the Chinese Navy is expected to create a foundation for the international community to recognize the West Sea as China's inland sea through "routine entry" and "exercise authority", and in case of emergency, it will try to secure sea control in the West Sea in a short period of time by blocking Korea's maritime transportation route based on the overwhelming preemptive attack capability of aircraft carriers. At the means level, it is accelerating the construction of aircraft carrier warfare units and improving its ability to engage long-range missiles. As a direction of development of the Korean Navy's response strategy in response to this, first, Establishment and Development of National Maritime Security Strategy in conjunction with the Korean Indo-Pacific Strategy. Second, it proposes the development of the concept of effective security operations for the east sea area of the West Sea intermediate line, and third, the development of the concept of combat performance and capacity building to strengthen survival and lethality.

• Progress in Medical Physics
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• v.18 no.2
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• pp.98-106
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• 2007

In June 2005, Yonsei University Medical Center, Severance Hospital upgraded a full-PACS system by adding twenty (5 mega pixels) Totoku ME511L flat panel LCD display devices for diagnostic interpretation purposes. Here we report upon the quantitative (or visual) acceptance testing of the twenty Totoku ME511L display devices for reflection, luminance response, luminance spatial dependency, resolution, noise, veiling glare, and display chromaticity based on AAPM TG 18 report. The tools used in the tests included a telescopic photometer, which was used as a colorimeter, illuminance meter, light sources for reflection assessment, light-blocking devices, and digital TG18 test patterns. For selected 8 flat panel displays, mean diffuse reflection coefficient ($R_d$) was $0.019{\pm}0.02sr^{-1}$. In the luminance response test, luminance ratio (LR), maximum luminance difference ($L_{max}$), and deviation of contrast response were $550{\pm}100,\;2.0{\pm}1.9%\;and\;5.8{\pm}1.8%$, respectively. In the luminance uniformity test, maximum luminance deviation was $14.3{\pm}5.5%$ for the 10% luminance of the TG18-UNL10 test pattern. In the resolution test with luminance measurement method, percent luminance (${\Dalta}L$) at the center was $0.94{\pm}0.64%$. In all cases of noise testing, rectangular target In every square in the three quadrants was visible and all 15 targets except the smallest one in the every corner pattern and the center pattern. The glare ratio (GR) was $12,346{\pm}1,995$. The color uniformity, (u',v'), was $0.0025{\pm}0.0008$. Also, the research results of qualify control guideline of primary disply devices suitable for domestic circumstance are presented All test results are in-line with the criteria recommended by AAPM TG18 report and are thus fully acceptable for diagnostic image interpretation. As a result, the acceptance testing schedule described provides not only an acceptance standard but also guidelines for quality control, optimized viewing conditions, and a means for determining the upgrading time of LCD display devices for diagnostic interpretation.

• Journal of Life Science
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• v.33 no.12
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• pp.1002-1014
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• 2023

The root of Cirsium japonicum var. maackii (Maxim.) has long been used in traditional medicine to prevent the onset and progression of various diseases and has been reported to exert a wide range of physiological effects, including antioxidant activity. However, research on its effects on hepatocytes remains scarce. This study used the human hepatocellular carcinoma HepG2 cell line to investigate the antioxidant activity of ethanol extract of C. japonicum root (EECJ) on hepatocytes. Hydrogen peroxide (H₂O₂) was used to mimic oxidative stress. The results showed that EECJ significantly reverted the decrease in cell viability and suppressed the release of lactate dehydrogenase in HepG2 cells treated with H₂O₂. Moreover, an analysis of changes in cell morphology, flow cytometry, and microtubule-associated protein light chain 3 (LC3) expression showed that EECJ significantly inhibited HepG2 cell autophagy induced by H₂O₂. Furthermore, it attenuated H₂O₂-induced apoptosis and cell cycle disruption by blocking intracellular reactive oxygen species and mitochondrial superoxide production, indicating strong antioxidant activity. EECJ also restored the decreased levels of intracellular glutathione (GSH) and enhanced the expression and activity of superoxide dismutase and GSH peroxidase in H₂O₂-treated HepG2 cells. Although an analysis of the components contained in EECJ and in vivo validation using animal models are needed, these findings indicate that EECJ is a promising candidate for the prevention and treatment of oxidative stress-induced liver cell damage.