• Journal of Mechanical Science and Technology
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• 제18권12호
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• pp.2104-2113
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• 2004

Surface degreasing method with premixed flame is proposed as the removal method of adherent impurities on materials. Effects of adherent molecular thickness and surface potential energy on evaporation rate of adherent molecules and molecular evaporation mechanism were investigated and discussed in the present study. Evaporation processes of adherent molecules on surface molecules were simulated by the molecular dynamics method to understand thermal phenomena on evaporation processes of adherent molecules by using high temperature gas like burnt gas. The calculation system was composed of a high temperature gas region, an adherent molecular region and a surface molecular region. Both the thickness of adherent molecules and potential parameters affceted the evaporation rate of adherent molecules and evaporation mechanism in molecular scale.

• International Journal of Automotive Technology
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• 제7권2호
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• pp.121-128
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• 2006

The interaction between adherent molecules and gas molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand evaporation and removal processes of adherent molecules on metallic surface using high temperature gas flow. Methanol molecules were chosen as adherent molecules to investigate effects of adhesion quantity and gas molecular collisions because the industrial oil has too complex structures of fatty acid. Effects of adherent quantity, gas temperature, surface temperature and adhesion strength for the evaporation rate of adherent molecules and the molecular removal mechanism were investigated and discussed in the present study. Evaporation and removal rates of adherent molecules from metallic surface calculated by the molecular dynamics method showed the similar dependence on the surface temperature shown in the experimental results.

• Journal of Advanced Marine Engineering and Technology
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• 제31권8호
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• pp.932-938
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• 2007

The interaction between adherent molecules and gas molecules was modeled in molecular scale and simulated by the molecular dynamics method in order to understand the evaporation and removal processes of adherent molecules on metallic surface using high temperature gas flow. Methanol molecules were chosen as adherent molecules to investigate effects of adhesion quantify and gas molecular collisions because the industrial oil has too complex structures of fatty acid. The effects of adherent quantify, gas temperature and surface temperature for the evaporation rate of adherent molecules and the molecular removal mechanism were investigated and discussed in the present study. Evaporation and removal rates of adherent molecules from metallic surface calculated by the molecular dynamics method showed the similar dependence on surface temperature shown in the experimental results.

• Biomolecules & Therapeutics
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• 제11권2호
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• pp.85-90
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• 2003

Microtubule-binding molecules have been developed as anti-cancer agents to overcome the toxicities of current chemotherapeutics and also have potential for use as anti-angiogenic agents. In this work, we examined the effect of novel triazine compounds, Tubulyzines (microTUBUle LYsing triaZINE), derived from the orthogonal synthesis of a triazine library, on endothelial progenitor cell differentiation. When mononuclear cells isolated from human cord blood were cultured on fibronectin-coated plates for 7 days, all the Tubulyzine compounds A, B, and C (TA, TB, and TC) tested decreased the number of adherent cells in a dose-dependent manner in a coo. centration ranges of 2-5 to $80\mu\textrm{M}$. TA ($IC_{50}$=$20\mu\textrm{M}$) showed slightly more potent activity than TB and TC. Adherent cells treated with TA also exhibited a lower level of ability to ac-LDL uptake, with low ratios of positive cells out of total adherent cells, in a dose-dependent manner and weak expression of endothelial lineage markers, KDR, CD31, and vWF at $20\mu\textrm{M}$. Therefore, these results suggest that tubulyzine A (TA) can be effectively used for the inhibition of new vessel growth by inhibiting differentiation of endothelial progenitor cells.

• Natural Product Sciences
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• 제9권4호
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• pp.273-277
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• 2003

Salicornia herbacea is an annual herb growing in salt marshes and on muddy seashores. Salicornia herbacea has been used as a fork medicine as well as a seasoned vegetable. In fork medicine, Salicornia herbacea has been used to treat a variety of diseases such as constipation, obesity, diabetes, asthma, arthritis and cancer. However, the biological mechanisms for these activities have not been characterized, nor the active components. The immunomodulatory activity of Salicornia herbacea components were studied in the present study. The components of Salicornia herbacea were prepared from the whole plant by passage through a fine screen, and then dialyzed against PBS overnight. Immunomodulatory activities of the Salicornia herbacea components were examined on a mouse macrophage cell line, RAW 264.7 cells. The Salicornia herbacea components were shown to stimulate cytokine production, nitric oxide release, and expression of surface molecules in a dose dependent manner. The Salicornia herbacea components also induced further differentiation of slightly adherent RAW 264.7 cell into strongly adherent macrophages. These results indicate that Salicornia herbacea contains immunomodulator(s) that induces activation of macrophages.

• Tuberculosis and Respiratory Diseases
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• 제43권2호
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• pp.210-220
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• 1996

식세포인 호중구나 단핵세포는 생체외실험에 사용하기 위한 세포분리법인 플라스틱 표면부착만으로도 세포활성화가 일어나 이후의 실험결과에 영향을 주고 이 과정에 부착분자가 연관되어 있는 것으로 알려져 있다. 폐의 주된 면역세포인 폐포대식세포도 대부분 플라스틱 표면부착에 의해 세포를 분리하므로 사람의 폐포대식세포가 표면부착 자체에 의해 활성화되는지 알아보고 세포활성회에 부착분자와 같은 기전이 관여하는지 밝히기 위해 적어도 한 쪽 폐가 정상인 사람에서 기관지폐포세척술을 통해 얻은 폐포대식세포를 대상으로 표면 부착이 미치는 영향을 과산화수소 분비량 측정으로 분석하여 다음과 같은 결과를 얻었다. 1) 폐포대식세포는 플라스틱 표면에 부착되면 부착 자체에 의해 과산화수소 분비능이 증가하고 이런 상태에서는 PMA나 fMLP와 같은 추가적인 화학자극물질에 의해 과산화수소 분비가 증가되지 않았다. 2) 여러가지 표면중 A549세포단층에 부착될 경우에만 이후의 PMA와 fMLP자극 모두에 의해 과산회수소 분비가 증가하였다. 3) PMA는 세포 부착여부에 관계없이 과산화수소 분비를 자극하지만 fMLP는 폐포대식세포가 표면에 부착된 상태에서만 자극효과가 나타났고 이런 부착세포에서의 fMLP에 의한 과산회수소 분비 효과는 단백합성억제제인 cycloheximide, G단백차 단제인 일해독소와 $\beta_2$ integrin 부착분자에 대한 항체인 항CD18 단세포항체 3가지 모두의 의해 차단되었다. 이상의 결과로 사람의 폐포대식세포는 플라스틱 부착자체에 의해 활성화되므로 부착 이후의 자극물질에 대한 효과가 반감되지만 폐포상피세포와 같은 생물학적 표면에 부착될 경우에는 이후의 세포자극에 민감하게 반응한다는 것을 알 수 있었고, PMA는 세포 부착여부에 관계없이 세포를 자극하는 반면 fMLP는 세포 부착상태에서만 자극효과가 나타나며 이런 부착세포에서의 fMLP에 의한 산소유리기 자극효과는 G단백결합 수용체를 통한 새로운 단백합성 과정으로 이루워지면서 $\beta_2$ integrin을 통한 폐포대식세포와 폐포상피세포의 부착에 의존하는 것으로 사료된다.

• Molecules and Cells
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• 제24권2호
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• pp.153-166
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• 2007

The syndecan family of heparan sulfate proteoglycans is expressed on the surface of all adherent cells. Syndecans interact with a wide variety of molecules, including growth factors, cytokines, proteinases, adhesion receptors and extracellular matrix components, through their heparan sulfate chains. Recent studies indicate that these interactions not only regulate key events in development and homeostasis, but also key mechanisms of the host inflammatory response. This review will focus on the molecular and cellular aspects of how syndecans modulate tissue injury and inflammation, and how syndecans affect the outcome of inflammatory diseases in vivo.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2008년도 Proceedings of the Convention
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• pp.103-115
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• 2008

Hemodynamic shear stress, the dragging force generated by blood flow, is known as an anti-atherogenic factor. We tested whether lysyl-tRNA synthetase (KRS) will be utilized as an agent controlling shear-sensing systems. KRS was previously known to be secreted as a pro-inflammatory agent. Here we found that KRS inhibited various shear-stimulated signaling pathways. We further found that KRS binds to detergent-resistant membrane (DRM), indicating that KRS binding molecules exist in DRM, specialized regions of the plasma membrane. DRM plays important roles in a variety of cellular processes and consists of gangliosides, signaling molecules and cytoskeletons. We then determined that KRS was colocalized with integrins ${\alpha}4$, ${\alpha}5$ and $av{\beta}3$. In addition, KRS was shown to be associated with sialic acid, existing at the end of gangliosides. Interestingly, the adherent effect of KRS was inhibited by pretreatment with sialic acid. Moreover, treatment of endothelial cells with neuraminidase appeared to inhibit both the KRS adhesion to endothelial cells and shear-stimulated signaling. In conclusion, KRS is likely to be utilized as a vascular regulator.

• 공업화학
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• 제16권6호
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• pp.725-730
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• 2005

경조직 대체용 생체재료의 개발에 있어서 재료의 생체적합성 및 골전도성은 가장 중요한 고려사항 중의 하나이다. 인산칼슘 박막은 경조직과 화학적 성분이 매우 유사하기 때문에 재료의 표면에 인산칼슘 박막을 형성함으로써 재료의 생물학적 성질을 매우 증진시킬 수 있다. 생체재료의 성공여부는 재료의 표면에 대한 부착단백질의 작용에 의해 결정되는데, 이는 부착단백질들이 세포의 부착 및 부착된 세포의 생물학적 반응을 유도하기 때문이다. 재료의 표면에 대한 부착단백질들의 흡착기전과 흡착된 입체구조에 따라 조골세포의 부착, 증식, 그리고 분화와 같은 세포반응이 향상되거나 또는 억제된다. 인산칼슘 박막에 의해 개질된 생체재료의 경우 골전도성이 높은 것으로 알려져 있다. 조골세포의 분화 정도가 증가함은 물론 뼈 결절들이 신속하게 형성되는 것이 관찰되었다.

• 한국동물생명공학회지
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• 제38권3호
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• pp.121-130
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• 2023

Background: Coating a culture plate with molecules that aid in cell adhesion is a technique widely used to produce animal cell cultures. Extracellular matrix (ECM) is known for its efficiency in promoting adhesion, survival, and proliferation of adherent cells. Gelatin, a cost-effective type of ECM, is widely used in animal cell cultures including feeder-free embryonic stem (ES) cells. However, the optimal concentration of gelatin is a point of debate among researchers, with no studies having established the optimal gelatin concentration. Methods: In this study, we coated plastic plates with gelatin in a concentration-dependent manner and assessed Young's modulus using atomic force microscopy (AFM) to investigate the microstructure of the surface of each plastic plate. The adhesion, proliferation, and differentiation of the ESCs were compared and analyzed revealing differences in surface microstructure dependent on coating concentration. Results: According to AFM analysis, there was a clear difference in the microstructure of the surface according to the presence or absence of the gelatin coating, and it was confirmed that there was no difference at a concentration of 0.5% or more. ES cell also confirmed the difference in cell adhesion, proliferation, and differentiation according to the presence or absence of gelatin coating, and also it showed no difference over the concentration of 0.5%. Conclusions: The optimum gelatin-coating for the maintenance and differentiation of ES cells is 0.5%, and the gelatin concentration-mediated microenvironment and ES cell signaling are closely correlated.