• Title/Summary/Keyword: Adhesion Factor

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Control of Platelet Rolling and Adhesion

  • Moskowitz, Samuel E.
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.77.1-77
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    • 2002
  • Platelets arrest bleeding and repair damaged blood vessels. The purpose of this paper is to formulate a mathematical model for the control of platelet adhesion within the vasculature consistent with experimental findings, particularly those of Frenette, Ruggeri , Savage, Yuan, Lawrence and Springer. In addition to providing some, albeit rudimentary, insight into the behavior of platelets, a numerical simulation of this theoretical model may be useful in a systematic study of pathological cases. Glycoprotein receptor complex (GPIb/V/IX), found on the platelet surface membrane, binds to the adhesive protein and ligand von Willebrand factor (vWf), located within the sub-endothelium. The binding...

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EFFECT OF CARBON FIBER SURFACE PROPERTIES ON FIBER-MATRIX ADHESION OF THE COMPOSITES

  • Kim Mun-Han;Park Su-Jin;Lee Jae-Rak;Choe Seon-Ung
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 1999.11a
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    • pp.40-43
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    • 1999
  • Electrochemical surface treatment of PAN-based carbon fibers in acidic electrolyte has been studied in increasing the surface functional groups on fiber surfaces for the improvement of fiber-matrix adhesion of the resulting composites. According to the FT-IR and XPS measurements, it reveals that the oxygen functional groups on fibers are largely influence on the composite mechanical behaviors, whereas the nitrogen functional groups are not affected in the system. In this work, a good correlation between surface functionality and mechanical properties is established.

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Protein tyrosine phosphatase PTPN21 acts as a negative regulator of ICAM-1 by dephosphorylating IKKβ in TNF-α-stimulated human keratinocytes

  • Cho, Young-Chang;Kim, Ba Reum;Cho, Sayeon
    • BMB Reports
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    • v.50 no.11
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    • pp.584-589
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    • 2017
  • Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-${\alpha}$, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-${\alpha}$. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of ${\kappa}B$ ($I{\kappa}B$)-kinase ${\beta}$ ($IKK{\beta}$) at Ser177/181. This dephosphorylation led to the stabilization of $I{\kappa}B{\alpha}$ and inhibition of NF-${\kappa}B$ activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation in the skin by dephosphorylating p-$IKK{\beta}$ and inhibiting NF-${\kappa}B$ signaling.

Albumin and Antioxidants Inhibit Serum-deprivation-induced Cell Adhesion in Hematopoietic Cells

  • Han, Mi-Jin;Lim, Sung-Mee;Kim, Yu-Lee;Kim, Hyo-Lim;Kim, Kye-Ok;Sacket, Santosh J.;Jo, Ji-Yeong;Bae, Yoe-Sik;Okajima, Fumikazu;Im, Dong-Soon
    • Biomolecules & Therapeutics
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    • v.16 no.4
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    • pp.410-415
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    • 2008
  • Previously, we identified albumin as an inhibitory factor in serum for cell adhesion of T cells such as human Jurkat T and primary cultured human T cells. In the present study, we found that other hematopoietic cell lines including U-937 human monocytes, THP-1 human monocytes, K-562 promyelocytic leukemia cells, and HL-60 human leukemia cells, also adhere to tissue culture flasks when serum is withdrawn, and albumin exerts an inhibitory effect on cell adhesion by those cells, implying that this inhibition is a common phenomenon in hematopoietic cells. Furthermore, we found that cell adhesion is inhibited by antioxidants such as (-)-epigallocatechin- 3-gallate (EGCG), morin, and a-tocopherol. Our results suggest that albumin may inhibit basal cell adhesion of hematopoietic cells and that the oxidative balance in the plasma may be important for cell adhesion of hematopoietic cells in vivo.

A New Technique to Improve ZnO-based FBAR Device Performances

  • Mai, Linh;Lee, Jae-Young;Pham, Van Su;Yoon, Gi-Wan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.437-440
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    • 2007
  • This paper presents the improvement of the resonance characteristics of film bulk acoustic-wave resonator (FBAR) devices fabricated on multilayer Bragg reflectors (BRs) based on inserting ultra-thin chromium (Cr) adhesion layers into BRs and post-annealing processes. The measurements show excellent improvement of return loss $(S_{11})$ and Q-factor by the combined use of Cr adhesion layers and thermal treatments particularly for 120 minutes at $200^{\circ}C$.

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Uplift Capacity and Creep Behavior of Concrete Pile Driven in Clay (점토지반에 타입된 콘크리트 말뚝의 인발저항 및 크리프 거동)

  • 신은철;김종인;박정준;이학주
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.371-378
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    • 2001
  • The working load at pile is sometimes subjected to not only compression load but also lateral load and uplift forces. Pile foundation is essential and uplift load can be applied because of buoyancy, a typhoon, wind or seismic forces. This study was carried out to determine the uplift capacity of concrete pile foundation driven in clay. Pile was driven in clay, between pile and clay adhesion factor was estimated, and it is the mean value between the cast-in-situ-pile and steel pipe pile. When pile foundation is loaded for long time, creep behavior occurs. The behavior of creep is originated from the clay creep contacted with pile. The creep behavior of pile foundation embedded in clay is heavily depended on the thickness of clay around the pile shaft, pore water pressure in clay, and creep behavior of clay.

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High-Q factor ZnO-based Film Bulk Acoustic Resonator Devices

  • Yoon, Gi-Wan;Mai, Linh
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.61-65
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    • 2008
  • In this paper, we studied a ZnO-based film bulk acoustic resonator (FBAR) device fabricated on a specially designed multi-layerd Bragg reflector part. Very thin chromium adhesion layers (0,03um thick) were additionally deposited to improve the quality of the Bragg reflector and some thermal treatments were performed to improve the resonant characteristics of the device. At the operating frequency of ${\sim}2.7GHz$, excellent resonant characteristics were observed in terms of return loss and quality factor, and effective electromechanical coupling coefficient. These findings are expected to be highly promising and effective for improving the performance of the FBAR devices at high frequency.

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Thermal Improvements for 2.75 GHz-FBAR Devices

  • Mai, Linh;Lee, Jae-Young;Pham, Van-Su;Kabir, S. M. Humayun;Dong, Hoai-Bac;Yoon, Gi-Wan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.10a
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    • pp.196-199
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    • 2007
  • In this paper, we studied a ZnO-based film bulk acoustic wave resonator (FBAR) device fabricated on top of a novel multi-layered Bragg reflector with chromium adhesion layers $(0.03{\mu}m-thick)$ inserted. The performance of FBAR device could be significantly improved using proper thermal treatments. At ${\sim}2.75$ GHz, we could achieve good return loss and quality factor (Q). This device fabrication technique will be useful for the future mobile WiMAX applications.

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Diethyldithiocarbamate Suppresses an NF-κB Dependent Metastatic Pathway in Cholangiocarcinoma Cells

  • Srikoon, Pattaravadee;Kariya, Ryusho;Kudo, Eriko;Goto, Hiroki;Vaeteewoottacharn, Kulthida;Taura, Manabu;Wongkham, Sopit;Okada, Seiji
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.7
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    • pp.4441-4446
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    • 2013
  • Cholangiocarcinoma (CCA) is a tumor of biliary ducts, which has a high mortality rate and dismal prognosis. Constitutively activation of the transcription factor nuclear factor kappa-B (NF-${\kappa}B$) has been previously demonstrated in CCA. It is therefore a potential target for CCA treatment. Effects of diethyldithiocarbamate (DDTC) on NF-${\kappa}B$-dependent apoptosis induction in cancer have been reported; however, anti-metastasis has never been addressed. Therefore, here the focus was on DDTC effects on CCA migration and adhesiond. Anti-proliferation, anti-migration and anti-adhesion activities were determined in CCA cell lines, along with p65 protein levels and function. NF-${\kappa}B$ target gene expression was determined by quantitative RT-PCR. DDTC inhibited CCA cell proliferation. Suppression of migration and adhesion were observed prior to anti-CCA proliferation. These effects were related to decreased p65, reduction in NF-${\kappa}B$ DNA binding, and impaired activity. Moreover, suppression of ICAM-1 expression supported NF-${\kappa}B$-dependent anti-metastatic effects of DDTC. Taken together, DDTC suppression of CCA migration and adhesion through inhibition of NF-${\kappa}B$ signaling pathway is suggested from the current study. This might be a promising treatment choice against CCA metastasis.