• Title/Summary/Keyword: $A_{\alpha}$-matrix

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Formation of Cyclodextrin Adsorbent Using Fatty Acid as a Ligand and Fractionation of $\alpha$-, $\beta$- and ${\gamma}$-cyclodextrins (Fatty Acid를 Ligand로한 Cyclodextrin Adsorbent의 제조와 $\alpha$-, $\beta$-, ${\gamma}$-Cyclodextrin의 분획)

  • 정승환;박동찬이용현
    • KSBB Journal
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    • v.10 no.5
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    • pp.491-498
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    • 1995
  • In order to fraclionate ${\alpha}$-, ${\beta}$- and ${\gamma}$-cyclodextrins(CDs) from CD reaction mixture, various CD adsorbents were manufactured using fatty acids as the ligand molecules and anion exchange resins as matrix. Among several anion exchange resins, DEAE Cellulose was found to be the most suitable matrix for binding fatty acid. The binding stability between DEAE Cellulose and capric acid was tested under the various operation conditions, such as temperature, ethanol concentration, and ionic strength. Specific CD adsorbents manufactured with different chain-length fatty acids, saturated and unsaturated, were compared in terms of the recovery yield and selectivity of ${\alpha}$-, ${\beta}$- and ${\gamma}$-CDs. Stearic acid (C18, saturated) was identified as the most effective ligand for fractionation of ${\alpha}$-CD, and linoleic acid ((C18, unsaturated ) for ${\beta}$-CD. The spacer length between the matrix and ligand was required for effective adsorption of CDs, and the double bond in fatty acid molecules was also acted as an important factor determining recovery yield and selectivity. The elusion patterns of ${\alpha}$- and ${\alpha}$-, ${\beta}$-CD from column packed with stearic acid and linoleic acid CD adsorbents were also investigated at the various elusion conditions for fractionation of ${\alpha}$- and ${\beta}$-CD.

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Immunohistochemical Study for the Angiogenesis Factors and Vascular Wall Matrix Proteins in Intracranial Aneurysms (뇌동맥류에서 혈관형성 인자와 혈관벽 기질 단백에 대한 면역조직화학적 연구)

  • Kim, Jae Hong;Yim, Man Bin;Lee, Chang Young;Kim, Sang Pyo
    • Journal of Korean Neurosurgical Society
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    • v.29 no.12
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    • pp.1584-1591
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    • 2000
  • Objective : Until now, it has been little known about the biological mechanisms associated with the genesis, growth, and rupture of intracranial aneurysm. This study was performed to investigate and understand a part of these mechanisms. Materials and Methods : Immunohistochemical stains for angiogenesis growth factors(basic fibroblast growth factor (bFGF) and vascular endothelial growth factor(VEGF)) and selected vascular wall matrix proteins(alpha smooth muscle actin(${\alpha}SMA$) and collagen Type IV) were performed in fixed sections from a normal circle of Willis artery which was taken from the autopsy specimen as a control vessel and 17 aneurysmal wall specimens which was taken during surgical clipping of aneurysms. The staining intensity and distribution of immunoreactivity to angiogenesis growth factors and selected wall matrix proteins in control vessel and aneurysmal wall were examined and compared with each other. The difference of staining intensity according to the size of aneurysm was also investigated. Results : There was no immunoreactivity to bFGF and VEGF in the control vessel. bFGF immunoreactivity was exhibited in 15 of 17 aneurysm specimens around smooth muscle cells within the media of aneurysm. VEGF immunoreactivity was also exhibited in all aneurysm specimens in patches or diffusely affecting all layers of the aneurysmal wall. The degrees of intensity of bFGF and VEGF immunoexpression were proportionate roughly to the size of aneurysm. Strong immunoexpression of both factors were noticed in large aneurysm. A regularly arranged and defined band of immunoreactivity of ${\alpha}SMA$ was noticed in the media of the control vessel, whereas diffuse, faint, irregularly arranged ${\alpha}SMA$ was noticed in the aneurysmal wall. A regularly defined band of collagen Type IV immunoreactivity was also noticed in the subendothelium of the control vessel, whereas diffuse disorganized immunoreactivity of collagen Type IV was noticed in the entire wall of the aneurysm. Conclusion : These results indicate substantial evidences of abnormal expression of angiogenesis factors and changes of selected vascular wall matrix proteins in the wall of intracranial aneurysm. The unbalanced changes of angiogenesis factors and vascular wall matrix proteins in the wall of aneurysm may be one of the biological mechanisms for the growth and rupture of aneurysm.

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Anti-aging Effect of Cycloheterophyllin in UVA-irradiated Dermal Fibroblasts (자외선 조사에 의해 노화된 섬유아세포에서 Cycloheterophyllin의 항노화 효능)

  • Shim, Joong Hyun
    • Korean Journal of Pharmacognosy
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    • v.50 no.4
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    • pp.285-290
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    • 2019
  • This study was carried out to identify the skin anti-aging effect of cycloheterophyllin on dermal fibroblasts. To elucidate anti-aging effects of cycloheterophyllin on dermal fibroblasts, I measured cell viability, mRNA expressions, and Collagen, type I/matrix metallopeptidase 1(MMP1)-ELISA assay. In this study, I investigated the effects of cycloheterophyllin on Collagen, type I, alpha 1(COL1A1)/Collagen, type III, alpha 1(COL3A1)/MMP1/Superoxide dismutases/Catalase(CAT) mRNA expressions and Collagen, type I/MMP1 protein production. Quantitative Real-time RT-PCR showed that cycloheterophyllin increased mRNA level of COL1A1/COL3A1/CAT genes and collagen, type I protein by ELISA assay compared to UVA-treated dermal fibroblasts. Furthermore MMP1 mRNA and protein expressions were decreased by cycloheterophyllin treatment. These observations revealed that cycloheterophyllin increased anti-aging effects in dermal fibroblasts. Therefore, I identified the anti-aging effects of cycloheterophyllin, and these results showed that the cycloheterophyllin can be a considerable potent ingredient for skin anti-aging. Based on this, I anticipated further researches about cycloheterophyllin for mechanism to develop not only cosmetics but for healthcare food or medicine.

Inhibitory Effects of Carex humilis Extract on Elastase Activity and Matrix Metalloproteinase-1 Expression (산거울 추출물의 Elastase 활성 저해 및 Matrix Metalloproteinase-1 발현 억제 효과)

  • Park, Sun-Hee;Lee, Kang-Hyuk;Han, Chang-Sung;Kim, Ki-Ho;Kim, Young-Heui
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.36 no.2
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    • pp.129-136
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    • 2010
  • In order to evaluate anti-wrinkle activity of Carex humilis extract, free radical scavenging activity, elastase inhibitory activity and reduction of expression Matrix metalloproteinase-1 (MMP-1) mRNA and MMP-1 protein were investigated. The roots of Carex humilis were extracted with 95 % ethanol and successively partitioned with organic solvents with increasing polarity of the solvents. Each fraction of organic solvent were investigated by using free radical scavenging activity and elastase inhibitory activity test. Among them, EtOAc fraction showed antioxidant activity ($SC_{50}$=4.89 ${\mu}g/mL$) and elastase inhibitory activity ($IC_{50}$=23.5 ${\mu}g/mL$). EtOAc fraction was developed on silica gel by open-column chromatography and consecutively re-developed on C18 resin by prep-HPLC to give ${\alpha}$-viniferin as a major component, which was confirmed by spectrometric analysis. In the assay on expression of MMP-1 mRNA by RT-PCR and protein by western-blot, EtOAc layer (10 ~ 100 ${\mu}g/mL$) was reduced about 50 ~ 60 %, 50 ~ 65 % respectively and ${\alpha}$-viniferin (0.5 ~ 2 ${\mu}g/mL$) was inhibited about 60 ~ 75 %, 55 ~ 65 % respectively in human fibroblast. Therefore, our findings suggest that EtOAc layer of Carex humilis containing ${\alpha}$-viniferin can be useful as an active ingredient for cosmeceuticals of anti-wrinkle effects.

The Chemokine SDF-1α Suppresses Fibronectin-mediated In Vitro Lymphocytes Adhesion

  • Ji, LiLi;Sheng, YuChen;Wang, ZhengTao
    • Molecules and Cells
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    • v.22 no.3
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    • pp.308-313
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    • 2006
  • Stromal cell-derived factor (SDF-1) is a CXC chemokine that selectively activates the CXCR4 chemokine receptor. Fibronectin is an intracellular matrix component that binds integrin and mediates cell-matrix adhesion. Activation of the integrin receptor can occur in two ways: by ligand binding (outside-in signaling), and in response to intracellular events (inside-out signaling). In the current study we showed that SDF-$1{\alpha}$ inhibited adhesion of T lymphocyte Jurkat cells resulting from binding high concentrations of fibronectin as well as that of THP-1 monocytes. The effect of SDF-$1{\alpha}$ on fibronectin-mediated adhesion was partly reversed by the CXCR4 receptor antagonist T140. Our results suggest that an SDF-1/CXCR4 signal pathway modulates fibronectin-mediated lymphocytes adhesion.

Study on the Effect of Crystal Morphology on Mechanical Property in Cu-Zn-Al Shape Memory Alloy (Cu-Zn-Al 형상기억합금에서 기계적 성질에 미치는 결정형상의 영향에 관한 연구;주조조직과 재결정처리에 따른 기계적 성질과 형상기억능의 변화)

  • Hwang, Sung-Jun;Lee, Jin-Hyung;Hong, Jong-Hwi
    • Journal of Korea Foundry Society
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    • v.9 no.1
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    • pp.58-66
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    • 1989
  • The effect of heat treating temperature and ${\alpha}$ phase In the ${\beta}$ phase matrix were investigated for ${\beta}-CuZnAl$ shape memory alloys by tension test, fatigue test, and shape memory effect test. After heat treatment at $677^{\circ}C$, $750^{\circ}C$, $800^{\circ}C$ and $850^{\circ}C$ for 10 min. respectively, static fracture stress(${\sigma}_f$), fatigue fracture stress(${\tau}_{max}$) at $10^6$ cycle, and elongation(${\epsilon}_f$) was $24.2kg/mm^2$, $17.21kg/mm^2$ and 11.8%, respectively. As heat treating temperature decreased, fracture surfaces of the specimens were changed from the intergranular to the transgranular fracture mode. Especially, the a phase precipitated in the ${\beta}$ phase matrix had an effect on crack propagation and the fracture surface was characterized by dimple-like pattern when crack propagated in transgranular cracking mode. Precipitation of the ${\alpha}$ phase in the ${\beta}$ phase matrix lowered the transformation temperature by $10^{\circ}C$, and about 2.5 vol.% ${\alpha}$ phase did not affect the shape memory effect examined by the bending test.

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Physical Property and Phase Transformation in a Commercial Dental Casting High Gold Alloy (시판치과주조용 고금합금의 물리적 성질 및 상변태)

  • Lee, Hee-Kyung;Park, Myoung-Ho;Lee, Hwa-Sik
    • Journal of Technologic Dentistry
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    • v.28 no.1
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    • pp.27-41
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    • 2006
  • The physical property and phase transformation in a commercial dental casting high gold alloy was investigated as a function of ageing temperature and time using microvickers hardness tester, X-ray diffraction, optical and electron microscopy and EPMA analyser. 1. With increasing ageing time, the hardness of solution-treated gold alloys increased slowly at the initial stage of ageing treatment at an ageing temperature of $300{\sim}400^{\circ}C$, and it reached a maximum value of hardness at the medium stage. Finally, it decreased gradually during further ageing. The maximum value of hardness at was similar with that of the conventional materials and suitable for using as the crown & bridge. 2. During isothermal ageing at a temperature range of $300{\sim}400^{\circ}C$, three phases consisting of the Au-rich ${\alpha}_1$phase with a face-centered cubic structure, the Pt3Zn ${\alpha}_2$phase with an ordered AuCu3(L12) type(f.c.c.) and the Pt-rich ${\alpha}_3$phase with face-centered cubic structure in solution-treated gold alloys were transformed into different three phases consisting of the ${\alpha}_1$phase, the ${\alpha}_3$phase and the PtZn $\beta$phase with an ordered AuCu I(L10) type. 3. The hardening of gold alloys was attributed to the lattice strains of the matrix resulting from the transformation of the ${\alpha}_2$phase to the $\beta$phase. 4. The softening of gold alloys during over-ageing was attributed to the coarsening of the nodules consisting of the $\beta$phase and ${\alpha}_1$matrix.

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REFLEXIVE PROPERTY SKEWED BY RING ENDOMORPHISMS

  • Kwak, Tai Keun;Lee, Yang;Yun, Sang Jo
    • Korean Journal of Mathematics
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    • v.22 no.2
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    • pp.217-234
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    • 2014
  • Mason extended the reflexive property for subgroups to right ideals, and examined various connections between these and related concepts. A ring was usually called reflexive if the zero ideal satisfies the reflexive property. We here study this property skewed by ring endomorphisms, introducing the concept of an ${\alpha}$-skew reflexive ring, where is an endomorphism of a given ring.

A Study on the High Temperature Deformation and the Cavity Initiation of Gamma TiAl Alloy ($\gamma$-TiAl 합금의 고온변형 및 Cavity 형성 연구)

  • Kim J. H.;Ha T. K.;Chang Y. W.;Lee C. S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.05a
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    • pp.172-175
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    • 2001
  • The high temperature deformation behavior of two-phase gamma TiAl alloy has been investigated with the variation of temperature and ${\gamma}/{\alpha}_2$ volume fraction. For this purpose, a series of load relaxation tests and tensile tests have been conducted at temperature ranging from 800 to $1050^{\circ}C$. In the early stage of the deformation as in the load relaxation test experimental flow curves of the fine-grained TiAl alloy are well fitted with the combined curves of two processes (grain matrix deformation and dislocation climb) in the inelastic deformation theory. The evidence of grain boundary sliding has not been observed at this stage. However, when the amount of deformation is large (${\epsilon}{\approx}$ 0.8), flow curves significantly changes its shape indicating that grain boundary sliding also operates at this stage, which has been attributed to the occurrence of dynamic recrystallization during the deformation. With the increase in the volume fraction of ${\alpha}_2$-phase, the flow stress for grain matrix deformation increases since ${\alpha}_2$-Phase is considered as hard phase acting as barrier for dislocation movement. It is considered that cavity initiation is more probable to occur at ${\alpha}_2/{\gamma}$ interface rather than at ${\gamma}/{\gamma}$ interface.

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The Study on the Effectiveness and Mechanism of Several Herbal Medicines for Development of Osteoarthritis Treatment (퇴행성관절염(退行性關節炎) 치료제 개발을 위한 수종의 한약재활성 검색 및 기전연구)

  • Huh Jeong-Eun;Cho Eun-Mi;Yang Ha-Ru;Kim Dae-Sung;Baek Yong-Hyeon;Lee Jae-Dong;Choi Do-Young;Park Dong-Suk
    • The Journal of Korean Medicine
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    • v.27 no.1 s.65
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    • pp.229-239
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    • 2006
  • Objectives : Articular cartilage is a potential target for drugs designed to inhibit the activity of matrix metalloproteinases (MMPs) to stop or slow the destruction of the proteoglycan and collagen in the cartilage extracelluar matrix. The purpose of this study was to investigate the effects of KHBJs for cartilage-protective effect in human and rabbit articular cartilage explants. Methods : The cartilage-protective effects of KHBJ were evaluated by using glycosaminoglycan degradation assay, collagen degradation assay, colorimetric analysis of MMPs activity, and histological analysis in rabbit and human cartilage explants culture. Results : KHBJs significantly inhibited GAG and collagen release of rabbit and human cartilage explant in a concentration-dependent manner. Also, KHBJs inhibited MMP-3 and MMP-13 activities from IL-$1{\alpha}$-treated cartilage explants cultures. Histological analysis indicated that KHBJ004 reduced the degradation of the cartilage matrix compared with that of IL-$1{\alpha}$-treated cartilage explants. KHBJ004 had no harmful effect on chondrocytes viability or cartilage morphology in cartilage explants. Conclusions : These results indicate that KHBJs inhibits the degradation of proteoglycan and collagen through the downregulation of MMP-3 and MMP-13 activities without affecting the viability or morphology of IL-$1{\alpha}$-stimulated rabbit and human articular cartilage explants.

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