• Animal cells and systems
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• v.4 no.4
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• pp.389-394
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• 2000

The Tcf-1 (1-cell factor-1) protein binds to the T-cell specific enhancer sequences and plays an architectural role in the assembly of transcriptional machinery. One of the Tcf family proteins, Tcf-4, was found to be an important regulator for colon cancer development where it activates specific genes upon binding to $\beta$-catenin following Wnt signaling. We were interested in the transcriptional regulatory activities of Tcf-1 and Tcf-4 proteins in T-cells and colon cancer cells. Transactivation assay was developed using a reporter plasmid containing luciferase gene under the control of Tcf responsive elements. Luciferase activity was determined following co-transfection of the reporter along with Tcf-1 and/or $\beta$-catenin expressing plasmids. Transcription was significantly induced by $\beta$-catenin expression in all cells. Tcf-1 by itself did not induce transcription in the mature T-cell lines, but overexpressed Tcf-1 greatly activated transcription in the immature T-cell line. In addition, transfected $\beta$-catenin induced apoptosis, but co-transfected Tcf-1 suppressed apoptosis in HEK293 cells. These results suggest that Tcf-1 and $\beta$-catenin differently regulate transcription and apoptosis.

• The Zoological Society Korea : Newsletter
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• v.18 no.1
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• pp.16-25
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• 2001

Wnt signaling의 주요 분자인 $\beta$-catenin의 기능과 조절에 관한 연구, 특히 TCF family 단백질과 함께 작용하는 신호전달에 관한 연구가 최근에 활발히 진행되고 있다. $\beta$-catenin 단백질은 Drosophila나 Xenopus의 발생초기에 중요한 역할을 한다는 것이 알려져 있고 Wnt (Wingless) 단백질에 의하여 활성화되는 신호전달 과정에 관여한다고 알려져 있으므로, TCF 단백질들이 Wnt signalling pathway에 작용한다는 것을 의미한다. 즉, $\beta$-catenin/TCF complex는 발생초기의 세포의 운명을 결정하는 세포의 분화에 중요하리라 생각된다. 또한 $\beta$-catenin/TCF complex는 세포의 암화에도 중요하다는 것이 보고되었다. 정상세포의 경우, $\beta$-catenin은 APC 라는 tumor suppressor에 의하여 결합하고 단백질의 분해가 유도되어 핵 안의 TCF와 결합하지 못하는데, 암세포의 경우 APC가 결실되었거나 $\beta$-catenin의 양이 과도하게 발현되어 암세포화 되는 것으로 보인다. 즉, $\beta$-catenin은 일종의 oncogene으로 작용하는 단백질이며, 그 작용에 필수적인 전사인자가 TCF라는 것이다. 특히, 대장암세포에서 이 $\beta$-catenin/TCF complex에 의해 활성화되는 유전자로서 c-myc과 cyclin Dl 등이 있는 것으로 보아, $\beta$-catenin/TCF 단백질은 세포의 증식 및 사멸에 관여하는 단백질들의 발현을 조절하는 매우 중요한 인자라고 생각된다.

• Journal of fish pathology
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• v.35 no.1
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• pp.93-102
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• 2022

This study performed a trichlorfon (TCF) residue and pharmacokinetic analysis with Japanese eels, Anguilla japonica, to obtain baseline data to establish the maximum residue level (MRL) of TCF in A. japonica. After dipping A. japonica in 30 ppm and 150 ppm of TCF at 28℃ and 18℃, drug residue in the body was analyzed with LC-MS/MS, and these results were further analyzed with the PK solver program to obtain the pharmacokinetic parameters of TCF in the serum, muscles, and liver. The maximum concentrations (C_max) in the serum, muscles, and liver were 25.87-357.42, 129.91-1043.73, and 40.47-375.20, respectively, and the time to maximum concentration (T_max) was 0.13-1.32h, 1.17-3.34h, and 0.14-5.40h, respectively. The terminal elimination half-life (T_1/2) was 2.13-3.92h, 5.30-10.35h, and 0.65-13.81h, respectively. In the 30 mg/L concentration group, TCF was not detected in the serum of eels 96 hours after bathing, and was below the detection limit after 336 hours in muscle and liver. On the other hand, in the 150 mg/L concentration group, TCF was not detected in the serum of eels 336 hours after bathing, but was detected in muscle and liver at 336 hours. In conclusion, the results of this study would be useful in establishing the MRL of TCF in farmed A. japonica.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.474-475
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• 2009

As a substitute of ITO material, carbon nanotube (CNT) is widely studied for transparent conductive film (TCF). Current sheet resistance of CNT-TCF is about 100 ${\Omega}$/sq at 80% transmittance. But CNT-TCF performance in manufacturable level is about 500 ${\Omega}$/sq at 83% based on the Topnanosys Co's result. Therefore, critical issue in CNT-TCF research is to reduce the sheet resistance with manufacturing reliability. In this report, recent developments using CNT-TCF are introduced. Touch panel, transparent LED signboard, transparent speaker and transparent heater are representative examples. Also I describe the future issues and prospect of CNT-TCF for the flexible display.

• Journal of the Korean Ceramic Society
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• v.45 no.1
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• pp.43-47
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• 2008

The photocatalyst of $TiO_2$ coated on a fly ash composites (TCF) was prepared from precipitant dropping method to remove the acetaldehyde by photocatalytic reaction. The TCF were characterized by crystal aize, crystal structure and specific surface area. The photodegradation of acetaldehyde has been investigated using a UV-illuminated fixed photocatalytic reactor with TCF catalyst and P-25 catalyst in gas phase. The effect of photodegradation reaction conditions, such as initial concentration of acetaldehyde, concentration of oxidant in mixed gas and the light intensity on the photodegradation of acetaldehyde were investigated. P-25 catalyst showed the highest photodegradation of acetaldehyde and anatase $TiO_2$ coated TCF showed higher decomposition rate than rutile coated TCF. The photodegradation rate of acetaldehyde increased with the decrease of flow rate, initial concentration of acetaldehyde ($C_i$) and water vapor, however, it was increased with the increas of UV light intensity. The optimum conditions were weight of TCF=10 g, flow rate=50 ml/min $C_i$=100 ppm, concentration of oxygen=20%, concentration of water vapor=100 ppm.

• The Journal of Korean Medicine
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• v.32 no.3
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• pp.35-43
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• 2011

Objectives: This study was performed to screen target-specific inhibitors of ${\beta}$-catenin/TCF signaling whose functional activation plays an important role in early events in carcinogenesis. Methods: To investigate the activation or suppression of ${\beta}$-catenin/TCF transcription, we established a transiently transfected cell line with a constitutively active ${\beta}$-catenin mutant gene whose product is not degraded. This cell line was also co-transfected with luciferase reporter gene constructs containing either an optimized (TOPflash) or mutant (FOPflash) TCF-binding element. We investigated cytotoxic effects using a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt (MTS) assay. To find effective inhibitors of ${\beta}$-catenin/TCF signaling from medicinal herbs, the crude extracts of 99 types of medicinal herbs were screened using a luciferase assay system in HEK-293 and SH-SY5y cells. Results: At a concentration of $50{\mu}g$/ml, extracts of Angelica koreanae radix, Cannabis sativa semen, Ephedrae intermedia Schrenk radix, and Vitis rotundifolia fruit showed the following inhibitory effects on ${\beta}$-catenin/TCF signaling: $40{\pm}5.6%$, $23{\pm}6.1%$, $8{\pm}5.1%$, and $22{\pm}9.8%$ in ${\beta}$-catenin-activated HEK-293 cells and $9{\pm}4.7%$, $39{\pm}8.1%$, $39{\pm}6.4%$, and $42{\pm}10.1%$ in ${\beta}$-catenin-activated SH-SY5y cells, respectively. Crude extracts of E. radix were isolated by silica gel column chromatography, and two non-polar fractions of these extracts showed inhibitory effects on ${\beta}$-catenin/TCF signaling. Conclusions: In this study, we established a transiently transfected cell line as a screening system and found that various medicinal herb extracts had inhibitory effects on ${\beta}$signaling.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.3
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• pp.79-81
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• 2008

A single-wall carbon nanotube (SWNT) transparent conductive film (TCF) was fabricated using a simple inkjet printing method. The TCF could be selectively patterned by controlling the dot size to diameters as small as $34{\mu}m$. In this repeatable and scalable process, we achieved 71% film transmittance and a resistance of 900 ohm/sq sheet with an excellent uniformity, about ${\pm}5%$ deviation overall. Inkjet printing of SWNT is substrate friendly and the TCF is printed on a flexible substrate. This method of fabrication using direct printing permits mass production of TCF in a large area process, reducing processing steps and yielding low-cost TCF fabrications on a designated area using simple printing.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.236-237
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• 2007

A single-wall carbon nanotube (SWNT) transparent conductive film (TCF) was fabricated using a simple inkjet printing method. The TCF could be selectively patterned by controlling the dot size to diameters as small as 34${\mu}m$. In thisrepeatable and scalable process, we achieved 71% film transmittance and a resistance of 900 ohm/sq sheet with an excellent uniformity, about $\pm$5% deviation overall. Inkjet printing of SWNT is substrate friendly and the TCF is printed on a flexible substrate. This method of fabrication using direct printing permits mass production of TCF in a large area process, reducing processing steps and yielding low-cost TCF fabrications on a designated area using simple printing.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1257-1260
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• 2007

A single-wall carbon nanotube (SWNT) transparent conductive film (TCF) was fabricated using a simple inkjet printing method. The TCF could be selectively patterned by controlling the dot size to diameters as small as $34\;{\mu}m$. In this repeatable and scalable process, we achieved 71% film transmittance and a resistance of 900 ohm/sq sheet with an excellent uniformity, about ${\pm}\;5%$ deviation overall. Inkjet printing of SWNT is substrate friendly and the TCF is printed on a flexible substrate. This method of fabrication using direct printing permits mass production of TCF in a large area process, reducing processing steps and yielding low-cost TCF fabrications on a designated area using simple printing.

• Bulletin of the Korean Chemical Society
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• v.21 no.10
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• pp.1049-1051
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• 2000

A chromia-pillared clay has been prepared by ion exchange type intercalation reaction between the sodium ion in montmorillonite and the trimeric chromium oxyformate (TCF) ion, and by subsequent heat-treatment. The structural and thermal properties have been systematically studied by thermal analysis, powder XRD, IR spec-troscopy, and XAS. The gallery height of~6.8 $\AA$ upon intercalation of the TCF ion suggests that the $Cr_3O$ plane is parallel to the aluminosilicate layers. Even though the basal spacing of TCF intercalated clay decreases slightly upon heating, the layer structure was retained up to $550^{\circ}C$ as confirmed by XRD and TG/DTA. Ac-cording to the EXAFS spectroscopic analysis, it is identified that the (Cr-Cr) distance of 3.28 $\AA$ between vertex-linked CrO6 octahedra in TCF splits into 2.64 $\AA$, 2.98 $\AA$, and 3.77 $\AA$ due to the face-, edge-, and corner-shared CrO6 octahedra after heating at $400^{\circ}C$, implying that a nano-sized chromium oxide phase was stabilized within the interlayer space of clay.