• Title/Summary/Keyword: Lyn

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SW Lyncis-Advances and Questions

  • Kim, Chun-Hwey;Kim, Ho-Il;Yoon, Tae-Seog;Han, Won-Yong;Lee, Jae-Woo;Lee, Chung-Uk;Kim, Jin-Hyung;Koch, Robert H.
    • Journal of Astronomy and Space Sciences
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    • v.27 no.4
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    • pp.263-278
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    • 2010
  • Many filtered CCD measures form the basis of six new light curves of the eclipsing system SW Lyn. From these measures and additional observations for eclipse timing, 47 new times of minimum light over the time-interval of about 13 years have been calculated. The complex period variability can be sorted into a linear period improvement with 5.8-year and 33.9-year periodic terms. The shorter cyclic term of these is ascribed to a cool companion of the eclipsing pair but the longer one has no testable interpretation at present. The new light curves are synthesized by the 2003 version of the Wilson-Devinney differential corrections computer code. The results incorporate a source of "third light" which comes from the cool companion star that had been identified by the cycling of the period of the eclipsing pair and also had previously been identified spectroscopically. There is a measure of satisfaction with current understanding of the SW Lyn eclipsing system because of consistent syntheses of all historical light curves. This agreeable convergence, however, comes partly at the expense of an unanticipated temperature of the hot star and of a photospheric spot that has no obvious basis in the detached character modeled for the binary. We offer predictions of changes in the stellar parameters if the modeled detached-configuration should be wrong. The SW Lyn stellar system is still difficult to understand.

Anti-allergic Effect of Graviola Leaf Extract in Human Mast Cells (인간 비만세포에서 그라비올라 잎 추출물의 항알러지 효과)

  • Kim, Dae-Yong
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.6
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    • pp.1764-1772
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    • 2020
  • This study is aimed at determining whether graviola (Annona muricata) beneficially influences immunoglobulin (Ig) E-mediated allergic reactions in human mast cells (LUVA cells). To examine the anti-allergic effect of graviola leaf extract (GLE), we treated antigen/IgE sensitized mast cells with extracts of various concentrations. In this study, the results of the in vitro model of IgE-mediated mast cell degranulation showed that GLE significantly inhibited the release of histamine, β-hexosaminidase, TNF-α, IL-4 and IL-6 in LUVA cells. Pretreatment with GLE suppressed the phosphorylation of antigen-induced Lyn and Syk, thus suppressing the downstream MAPKs pathways. The above results indicate GLE could suppress mast cell activation and allergic responses. Accordingly, it can be supported that GLE has the potential to be used as functional cosmetic material.

S100A8 and S100A9 Secreted by Allergens in Monocytes Inhibit Spontaneous Apoptosis of Normal and Asthmatic Neutrophils via the Lyn/Akt/ERK Pathway (단구에서 분비되는 S100A8과 S100A9의 Lyn/Akt/ERK 경로를 통한 정상인과 천식질환 호중구의 세포고사 억제 효과)

  • Kim, In Sik;Lee, Ji-Sook
    • Korean Journal of Clinical Laboratory Science
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    • v.49 no.2
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    • pp.128-134
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    • 2017
  • Der p 1 and Der p 2 are essential allergens of house dust mite associated with the development of asthma. In the present study, we examined whether Der p 1 and Der p 2 induce a release of S100A8 and S100A9 in monocytes, which are involved in the regulatory mechanism of neutrophil apoptosis. We found that Der p 1 and Der p 2 significantly increased the secretion of S100A8 and S100A9 in normal monocytes. Moreover, S100A8 and S100A9 strongly suppressed the spontaneous apoptosis of normal and asthmatic neutrophils. The inhibitory effect of S100A9 was stronger than that of S100A8, and asthmatic neutrophils showed a higher inhibitory effect than normal neutrophils. S100A8 and S100A9 induced activation of Lyn, Akt, and ERK in a time-dependent manner. These findings elucidate the roles of Der p 1 and Der p 2 in the interaction between monocytes and neutrophils, as well as contributing to our knowledge of the pathogenesis of allergic diseases.

Dasatinib Inhibits Lyn and Fyn Src-Family Kinases in Mast Cells to Suppress Type I Hypersensitivity in Mice

  • Lee, Dajeong;Park, Young Hwan;Lee, Ji Eon;Kim, Hyuk Soon;Min, Keun Young;Jo, Min Geun;Kim, Hyung Sik;Choi, Wahn Soo;Kim, Young Mi
    • Biomolecules & Therapeutics
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    • v.28 no.5
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    • pp.456-464
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    • 2020
  • Mast cells (MCs) are systemically distributed and secrete several allergic mediators such as histamine and leukotrienes to cause type I hypersensitivity. Dasatinib is a type of anti-cancer agent and it has also been reported to inhibit human basophils. However, dasatinib has not been reported for its inhibitory effects on MCs or type I hypersensitivity in mice. In this study, we examined the inhibitory effect of dasatinib on MCs and MC-mediated allergic response in vitro and in vivo. In vitro, dasatinib inhibited the degranulation of MCs by antigen stimulation in a dose-dependent manner (IC50, ~34 nM for RBL-2H3 cells; ~52 nM for BMMCs) without any cytotoxicity. It also suppressed the secretion of inflammatory cytokines IL-4 and TNF-α by antigen stimulation. Furthermore, dasatinib inhibited MC-mediated passive cutaneous anaphylaxis (PCA) in mice (ED50, ~29 mg/kg). Notably, dasatinib significantly suppressed the degranulation of MCs in the ear tissue. As the mechanism of its effect, dasatinib inhibited the activation of Syk and Syk-mediated downstream signaling proteins, LAT, PLCγ1, and three typical MAP kinases (Erk1/2, JNK, and p38), which are essential for the activation of MCs. Interestingly, in vitro tyrosine kinase assay, dasatinib directly inhibited the activities of Lyn and Fyn, the upstream tyrosine kinases of Syk in MCs. Taken together, dasatinib suppresses MCs and PCA in vitro and in vivo through the inhibition of Lyn and Fyn Src-family kinases. Therefore, we suggest the possibility of repositioning the anti-cancer drug dasatinib as a treatment for various MC-mediated type I hypersensitive diseases.

Effects of G-Rh2 on mast cell-mediated anaphylaxis via AKT-Nrf2/NF-κB and MAPK-Nrf2/NF-κB pathways

  • Xu, Chang;Li, Liangchang;Wang, Chongyang;Jiang, Jingzhi;Li, Li;Zhu, Lianhua;Jin, Shan;Jin, Zhehu;Lee, Jung Joon;Li, Guanhao;Yan, Guanghai
    • Journal of Ginseng Research
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    • v.46 no.4
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    • pp.550-560
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    • 2022
  • Background: The effect of ginsenoside Rh2 (G-Rh2) on mast cell-mediated anaphylaxis remains unclear. Herein, we investigated the effects of G-Rh2 on OVA-induced asthmatic mice and on mast cell-mediated anaphylaxis. Methods: Asthma model was established for evaluating airway changes and ear allergy. RPMCs and RBL-2H3 were used for in vitro experiments. Calcium uptake, histamine release and degranulation were detected. ELISA and Western blot measured cytokine and protein levels, respectively. Results: G-Rh2 inhibited OVA-induced airway remodeling, the production of TNF-α, IL-4, IL-8, IL-1β and the degranulation of mast cells of asthmatic mice. G-Rh2 inhibited the activation of Syk and Lyn in lung tissue of OVA-induced asthmatic mice. G-Rh2 inhibited serum IgE production in OVA induced asthmatic mice. Furthermore, G-Rh2 reduced the ear allergy in IgE-sensitized mice. G-Rh2 decreased the ear thickness. In vitro experiments G-Rh2 significantly reduced calcium uptake and inhibited histamine release and degranulation in RPMCs. In addition, G-Rh2 reduced the production of IL-1β, TNF-α, IL-8, and IL-4 in IgE-sensitized RBL-2H3 cells. Interestingly, G-Rh2 was involved in the FcεRI pathway activation of mast cells and the transduction of the Lyn/Syk signaling pathway. G-Rh2 inhibited PI3K activity in a dose-dependent manner. By blocking the antigen-induced phosphorylation of Lyn, Syk, LAT, PLCγ2, PI3K ERK1/2 and Raf-1 expression, G-Rh2 inhibited the NF-κB, AKT-Nrf2, and p38MAPK-Nrf2 pathways. However, G-Rh2 up-regulated Keap-1 expression. Meanwhile, G-Rh2 reduced the levels of p-AKT, p38MAPK and Nrf2 in RBL-2H3 sensitized IgE cells and inhibited NF-κB signaling pathway activation by activating the AKT-Nrf2 and p38MAPK-Nrf2 pathways. Conclusion: G-Rh2 inhibits mast cell-induced allergic inflammation, which might be mediated by the AKT-Nrf2/NF-kB and p38MAPK-Nrf2/NF-κB signaling pathways.

Modified Sequential Algorithm schema for Efficient Digital Image retrieval (Modified Sequential Algorithmic Schema를 이용한 디지털 사진의 효율적인 분류)

  • Lee, Sang-Lyn
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.237-240
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    • 2007
  • 이 논문에서는 수정된 Sequential Algorithmic Schema를 이용해서 여러 장소를 이동하면서 찍은 디지털 이미지를 효율적으로 분류할 수 있는 방법을 제안한다. 제안하는 방법은 이웃 패턴들과 특징 정보의 연속성, 유사성을 가지며 들어오는 입력 패턴에 대해 기존의 모든 군집과 유사도를 비교하는 방법이 아니라 이전 군집의 정보와 유사도를 비교하여 군집에 포함시키거나 동적으로 군집을 생성하는 효율적인 군집화 방법이다. 제안한 방법은 실험을 통해서 기존의 군집화 기법에 성능 및 속도의 효율성을 증명하였다.

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Magnetic beads separation using a multi-layered microfluidic channel (다층구조의 미세유체채널을 이용한 자성입자 분리)

  • Lee, Hye-Lyn;Song, Suk-Heung;Jung, Hyo-Il
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1685-1686
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    • 2008
  • This paper presents the design and experiment results of a multi-layered microsystem for magnetic bead applications. The magneto-microfluidic device is designed for capable of separating magnetic beads. In the presence of the magnetic field, magnetic beads are attracted and moved to high gradient magnetic fields. A multi-layered microfluidic channel consists of top and bottom layers in order to separate magnetic beads in the vertical direction. Our channel is easily integrated magnetic cell sorter, especially on-chip microelectromagnet or permanent magnet device. Fast separation of magnetic beads in top and bottom channels can be used in high throughput screening to monitor the efficiency of blood and drug compounds.

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A Performance Enhancement of Container ISO-code Recognition using Dynamic Time Warping (Dynamic Time Warping을 이용한 컨테이너 식별자 인식 성능 향상)

  • Lee, Sang-Lyn;Koo, Kyung-Mo;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.10a
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    • pp.977-980
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    • 2007
  • 본 논문은 인식된 컨테이너 식별자 문자열과 컨테이너 작업리스트를 비교하여 작업리스트와 인식된 컨테이너 식별자 문자열을 매칭하는 효율적인 방법을 소개하고자 한다. Dynamic Time Warping 기법을 이용하여 오인식되거나 인식이 되지 않은 문자에 대하여 오독률을 최소화할 수 있는 효율적인 방법을 제안한다. 기존의 문자열 비교방식에 비하여 제안하는 방법을 사용하였을 경우 더 나은 성능을 보였다.

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Application of Subgrid Turbulence Model to the Finite Difference Lattice Boltzmann Method (차분 래티스볼츠만법에 Subgrid 난류모델의 적용)

  • Kang Ho-Keun;Ahn Soo-Whan;Kim Jeong-Whan
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.5
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    • pp.580-588
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    • 2006
  • Two-dimensional turbulent flows past a square cylinder and cavity noise are simulated by the finite difference lattice Boltzmann method with subgrid turbulence model. The method, based on the standard Smagorinsky subgrid model and a single-time relaxation lattice Boltzmann method, incorporates the advantages of FDLBM for handling arbitrary boundaries. The results are compared with those by the experiments carried out by Noda & Nakayama and Lyn et al. Numerical results agree with the experimental ones. Besides, 2D computation of the cavity noise generated by flow over a cavity at a Mach number of 0.1 and a Reynolds number based on cavity depth of 5000 is calculated. The computation result is well presented a understanding of the physical phenomenon of tonal noise occurred primarily by well-jet shear layer and vortex shedding and an aeroacoustic feedback loop.