• Animal cells and systems
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• v.1 no.4
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• pp.657-663
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• 1997

The CD4 and CDS coreceptors, in conjunction with the T cell receptor (TCR) , make important contributions to the differentiation of thymocytes. They have been shown to be involved in the clonal deletion and positive selection processes during T cell development in thymus. To further analyze the role of CD4 and CDS proteins during T cell differentiation, we have generated transgenic mice constitutively expressing high levels of a native CD4 and a CD4{CDSa hybrid protein. The hybrid protein is composed of CD4 extracellular domain linked to the CD8a transmembrane region and cytoplasmic tail. The transgenes were driven by human beta-actin promoter, and therefore, they were expressed in all tissues examined including thymus, spleen, and lymph nodes. The resulting CD4 and CD4{CD8${\alpha}$transgenic mice were found to express the CD4 and CD4{CD8${\alpha}$ respectively, in developing thymocytes and peripheral T cells. The expression levels of transgenic proteins were 5-10 times higher than that of endogenous CD4 in thymus. However, total surface CD4 expression (CD4 or CD4{CD8${\alpha}$ transgenic protein plus endogenous CD4) of the transgenic mice were main. tained at similar levels compared to control littermates. Surface CD4 expression on CDS T cells, however, was significantly lower than that on cells expressing endogenous CD4. These results suggest that a total avidity between developing thymocytes and thymic stromal cells is impor. tant for differentiation of thymocytes.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.323-328
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• 2019

Tuberculosis, a chronic bacterial infection caused by Mycobacterium tuberculosis (MTB), differs in its status latency and activity because of the characteristics of MTB, immune status of the host, and genetic susceptibility. The host defense mechanism against MTB is caused mainly by interactions between macrophages, T cells, and dendritic cells. CD44 is expressed in activated T cells when infected with MTB and regulates lymphocyte migration. In addition, CD44 mediates leukocyte adhesion to the ECM and plays a role in attracting macrophages and $CD4^+$ T cells to the lungs. Therefore, genetic polymorphism of the CD44 gene will inhibit the host cell immune mechanisms against MTB. This study examined whether the genetic polymorphism of the CD44 gene affects the susceptibility of tuberculosis. A total of 237 SNPs corresponding to the CD44 genes were analyzed using the genotype data of 443 tuberculosis cases and 3,228 healthy controls from the Korean Association Resource (KARE). Of these, 17 SNPs showed a significant association with the tuberculosis case. The most significant SNP was rs75137824 (OR=0.231, CI: 1.51~3.56, $P=1.3{\times}10^{-4}$). In addition, rs10488809, one of the 17 significant SNPs, is important for the tuberculosis outbreak can bind to the JUND and FOS transcription factors and can affect CD44 gene expression. This study suggests that polymorphism of the CD44 gene modulates the host susceptibility to tuberculosis in a variety of ways, resulting in differences in the status of tuberculosis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.59-61
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• 1989

The cell parameters of the sintered CdS/CdTe solar cells in which te CuCl$_2$was added in the carbon paste after the sintering of the CdS/CdTe composites an were annealed at 35$0^{\circ}C$ for 10 min in nitrogen are investigated. Voc and FF do not change significantly as the CuCl$_2$increasing up to 500 ppm, Jsc increases with futher increase in copper. The hole concentration, determined by C-V measurement, increases to $1.5\times$10$^{16}$ ㎤ as the copper increased to 25 ppm and then stays at about the same value with further increase in copper.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.222-227
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• 2018

Mycobacterium tuberculosis (MTB)-originated lipid antigen is presented on the antigen-presenting cell surface with CD1b. When monocyte-derived dendritic cells phagocytosed MTB H37Rv (Multiplicity of infection 10, infectivity: 46.89%), the CD1b expression level decreased slowly. Since this was just a live MTB-mediated phenomenon, it was not detected from heat-killed MTB or mycolic acid, which is a unique antigen of MTB. We confirmed that the phosphorylation of CD1b molecules using 2D electrophoresis with staining could phosphorylate and induce the presentation of the lipid antigen using the phagocytosis assay.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.620-628
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• 2008

Cadmium sulphide (CdS) thin film, which is used as a window layer of heterojunction solar cell, on the glass substrate was deposited by vacuum evaporation. Effects of deposition conditions such as the source and substrate temperature on electrical and optical properties of CdS films was investigated. As the source temperature was increased, the deposition rate of CdS films was increased. In addition, the optical transmittance and the electrical resistivity of CdS films were decreased as the source temperature was increased. This results were attributed to the increase of excess Cd amount in the film. The crystal structure of CdS films exhibited the hexagonal phase with preferential orientation of the (002) plane. As the substrate temperature was increased, the crystal structure of CdS films was improved and the resistivity of the films was increased due to the decrease of excess Cd in film.

• IMMUNE NETWORK
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• v.15 no.3
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• pp.121-124
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• 2015

Now, it has been being accepted that reverse signaling through CD137 ligand (CD137L) plays an important role in vivo during hematopoiesis and in immune regulation. However, due to technical difficulty in dissecting both directional signaling events simultaneously in vivo, most biological activities caused by CD137-CD137L interactions are considered as results from signaling events of the CD137 receptor. To make the story more complex, $CD137^{-/-}$ and $CD137L^{-/-}$ mice have increased or decreased immune responses in a context-dependent manner. In this Mini review, I will try to provide a plausible explanation for how CD137L signaling is controlled during immune responses.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.700-704
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• 1993

The photocatalytic alanine and hydrogen production reaction were studied by using CdS as a semiconductor photocatalysts. The rate of alanine and hydrogen production depends strongly on the temperature in heat treatment of CdS powder. In particular, the rate of alanine production, which was observed using Pt/CdS(A)-(CdS from Mitsuwa), was increased about six times than that of using Pt/CdS(B)-(CdS from Furruchi) under the same heat treatment condition at 500$^{\circ}$C. And the photocatalytic activity for alanine production using bare CdS(A) or Pt/CdS(A) was almost same with increasing temperature in heat treatment in the range of 100-600$^{\circ}$C. From X-ray diffraction data and photoluminescence spectrum, we conclude that the crystal structure changes of CdS(A) or strong interaction at interface of Pt and CdS contribute to increasing the rate of alanine and hydrogen production reaction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.239-242
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• 2004

A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by hot wall epitaxy(HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$ respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. From the optical absorption measurement, the temperature dependence of energy band gap on $CdIn_2S_4$ single crystal thin films was found to be $E_g(T)\;=\;2.7116\;eV\;-\;(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. After the as-grown $CdIn_2S_4$ single crystal thin films was annealed in Cd-, S-, and In-atmospheres, the origin of point defects of $CdIn_2S_4$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3610-3613
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• 2011

CdS nanoparticles (NPs) were synthesized in an aqueous phase in order to investigate their spectral behaviors as efficient fluorescence resonance energy transfer (FRET) donors for various organic dye acceptors. Our prepared CdS NPs exhibiting strong and broad emission spectra between 480-520 nm were able to transfer energy in a wide wavelength region from green to red fluorescence dyes. Rhodamine 6G (Rh6G), rhodamine B (RhB), and sulforhodamine 101 acid (Texas red) were tested as acceptors of the energy transfer from the CdS NPs. The three dyes and synthesized CdS NPs exhibited good FRET behaviors as acceptors and donors, respectively. Energy transfers from the CdS NPs and organic Cy3 dye were compared to the same acceptor Texas red dye at different concentrations. Our prepared CdS NPs appeared to exhibit better FRET behaviors comparable to those of the Cy3 dye. These CdS NPs in an aqueous solution may be efficient FRET donors for various organic dyes in a wide wavelength range between green and red colors.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.325-329
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• 1996

We report on p-type arsenic doping of metalorganic vapor phase epitaxially (MOVPE) grown HgCdTe on (100) GaAs. HgCdTe was grown at $370^{\circ}C$ in a horizontal reactor with using dimethy-cadmium, diisoprophyltelluride, and elemental Hg. We used tris-dimethylaminoarsenic (DMAAs) as the metalorganic for p-doping. 4micron thick CdTe and subsequently 10micron thick HgCdTe were grown on (100) GaAs substrate. Interdiffused multilayer process in which thin CdTe and HgTe layers are grown alternately and interdiffused to obtain homogeneous HgCdTe alloys was used. Arsenic was doped during CdTe growth cycle. After growth HgCdTe was annealed at $415^{\circ}C$ for 15 min and then annealed again at $220^{\circ}C$ for 3 hr, both with Hg-saturate condition. We could obtain p-doping from 2.5$\times$$10^{16}$ to 6.6$\times$$10^{17}$$cm^{-3}$, depending on the DMAAs partial pressure. With the dual Hg-annealing, activation of arsenic was aboutt 90%, which was confirmed by SIMS measurement. With only low temperature annealing at $220^{\circ}C$ for 3hr, activation efficiency was about 50%.