• 대한의생명과학회지
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• 제3권2호
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• pp.71-76
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• 1997

실험적 자궁암 치료제로서 본 연구소에서 합성한 마이토센유사체를 인체 자궁암세포주인 SiHa, C33A, HeLa, CaSki에 처리하여, 체외 항암활성 측정시 합성 마이토센유사체들은 이 들 세포주에 대하여 대조 항암제들에 비하여 의의있는 세포독성을 보였으며, SiHa 세포주를 이용한 종양클론형성 억제검사에서는 22번 화합물만이 종양성장 억제활성이 가장 우수하였고 다른 화합물들은 대조항암제들에 비하여 활성이 낮았다. 이 마이토센유사체들에 대한 체외 항암감수성결과는 향후 전임상적인 자궁경부암 화합요법제의 기초자료로 유용할것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6301-6306
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• 2014

Cervical cancer is one the most common malignancies among females. In recent years, its incidence rate has shown a rising trend in some countries so that development of anticancer drugs for cervical cancer is an urgent priority. In our recent anticancer drug discovery screen, 1, 2-di (quinazolin-4-yl)diselane (LG003) was found to possess wide spectrum anticancer efficacy. In the present work, the in vitro anticancer activity of LG003 was evaluated in the SiHa cervical cancer cell line. Compared with commercial anticancer drugs 10-hydroxycamptothecin, epirubicin hydrochloride, taxol and oxaliplatin, LG003 showed better anticancer activity. Furthermore, inhibition effects were time- and dose-dependent. Morphological observation exhibited LG003 treatment results in apoptosis like shrinking and blebbing, and cell membrane damage. Lactate dehydrogenase release assay revealed that LG003 exerts such effects in SiHa cells through a physiology pathway rather than cytotoxicity, which suggests that title compound LG003 can be a potential candidate agent for cervical cancer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.184-186
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• 2002

$ITO_{(n)}/Si_{(p)}$ solar cell was fabricated by vaccum deposition method under the resistance heating with substrate temperature kept about 200[$^{\circ}C$] and than their properties are investigated. The cell charateristics can be improved by annealing but are deteriorated at temperature above 650[$^{\circ}C$] for longer than 15[min].

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1325-1331
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• 2012

Tumor formation and growth is dictated by a very small number of tumor cells, called cancer stem cells, which are capable of self-renewal. The genesis of cancer stem cells and their resistance to conventional chemotherapy and radiotherapy via mechanisms such as multidrug resistance, quiescence, enhanced DNA repair abilities and anti-apoptotic mechanisms, make it imperative to develop methods to identify and use these cells as diagnostic or therapeutic targets. Aldehyde dehydrogenase 1 (ALDH1) is used as a cancer stem cell marker. In this study, we evaluated ALDH1 expression in CaSki, HeLa and SiHa cervical cancer cells using the Aldefluor method to isolate ALDH1-positive cells. We showed that higher ALDH1 expression correlated with significantly higher rates of cell proliferation, microsphere formation and migration. We also could demonstrate that SiHa-ALDH1-positive cells were significantly more tumorigenic compared to SiHa-ALDH1-negative cells. Similarly, SiHa cells overexpressing ALDH1 were significantly more tumorigenic and showed higher rates of cell proliferation and migration compared to SiHa cells where ALDH1 expression was knocked down using a lentivirus vector. Our data suggested that ALDH1 is a marker of cervical cancer stem cells and expand our understanding of its functional role.

• Journal of Pharmaceutical Investigation
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• 제35권5호
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• pp.343-348
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• 2005

Recently, siRNA has been emerging as new therapeutic agents for various diseases such as cancers and infectious diseases. However, the evaluation for delivery systems for siRNA has not been fully done. In this study, we designed and delivered siRNA of oncogenic E6 and E7 proteins to several cell lines and tested the delivery efficiencies of various cationic nonviral delivery vectors. Of cationic delivery systems tested in this study, lipid-based Lipofectamine revealed higher delivery efficiency of siRNA to cervical cancer cell line, SiHa, compared to other delivery systems. Notably, the polyethylenimine, which showed the comparable delivery efficiencies in plasmid DNA, did not show significant delivery of siRNA in cervical cancer cells. These results indicate that the mechanisms involved in siRNA delivery might be different from those in plasmid DNA delivery, and that cationic lipid-based delivery vehicles deliver siRNA with higher efficiency to intracellular target sites.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.575-578
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• 2004

The charging tendency of $Zn_2SiO_4:Mn^{2+}$ phosphor surface was modified in order to improve discharging characteristic of green cell in an ac-plasma display panel (ac-PDP). The Zinc-silicate ($Zn_2SiO_4:Mn^{2+}$) green-emitting phosphor was coated with magnesium oxide(MgO), which is viable to have positive charge on the surface. After fabricating the green cell with MgO-coated $Zn_2SiO_4:Mn^{2+}$, the electrical and optical properties in the cell were examined. It was found that the dynamic voltage margin could be increased while the address time was reduced. It may be ascribed to the change of charging tendency of $Zn_2SiO_4:Mn^{2+}$ phosphor by MgO coating, which makes it possible to stable wall-charge accumulation. When $Zn_2SiO_4:Mn^{2+}$ phosphor was coated with 1.3wt%-MgO, the address time was reduced 1.2 ${\mu}s$ and the address voltage lowered 25 V without any misfiring problem, compared to those of typical $Zn_2SiO_4:Mn^{2+}$ phosphor layer. The luminescence intensity of green cell using MgO-coated phosphor layer was also improved by 10%.

• Korean Membrane Journal
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• 제3권1호
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• pp.69-74
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• 2001

Films of TiO$_2$/SiO$_2$ were deposited on the inner surface of the porous glass support tubes by decomposition of tetraisopropyl titanate (TIPT) and tetraethyl orthosilicate (TEOS) at atmospheric pressure. Dense and hydrogen -permselective membranes were formed at 400-600$\^{C}$. The permeation rates of H$_2$ through the membrane at 600$\^{C}$ were 0.2-0.4 ㎤(STP)/min-㎠ atm and H$_2$:N$_2$permeation ratios were above 1000. The permeation properties of the membranes were investigated at various deposition temperatures and TIPT/TEOS concentrations. Decomposition of TIPT alone at temperatures above 400$\^{C}$ produced porous crystalline TiO$_2$ films and they were not H7-selective. Decomposition of TEOS produced H$_2$-permeable SiO$_2$ films at 400-600$\^{C}$ but film deposition rate was very low. Addition of TIFT to the TEOS stream significantly accelerated the deposition rate and produced highly H$_2$-selective films. Increasing the TIPT/TEOS concentration ratio increased the deposition rate. The TiO$_2$/SiO$_2$ membranes formed at 600 $\^{C}$ have the permeation properties comparable to those of SiO$_2$ membranes produced from TEOS.

• 한국전기전자재료학회논문지
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• 제32권2호
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• pp.165-173
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• 2019

Lithium anodes (13, 15, 17, and 20 wt% Li) were fabricated by mixing molten lithium and iron powder, which was used as a binder to hold the molten lithium, at about $500^{\circ}C$ (discharge temp.). In this study, the effect of applied pressure and lithium content on the discharge properties of a thermal battery's single cell was investigated. A single cell using a Li anode with a lithium content of less than 15 wt% presented reliable performance without any abrupt voltage drop resulting from molten lithium leakage under an applied pressure of less than $6kgf/cm^2$. Furthermore, it was confirmed that even when the solid electrolyte is thinner, the Li anode of the single cell normally discharges well without a deterioration in performance. The Li anode of the single cell presented a significantly improved open-circuit voltage of 2.06 V, compared to that of a Li-Si anode (1.93 V). The cut-off voltage and specific capacity were 1.83 V and $1,380As\;g^{-1}$ (Li anode), and 1.72 V and $1,364As\;g^{-1}$ (Li-Si anode). Additionally, the Li anode exhibited a stable and flat discharge curve until 1.83 V because of the absence of phase change phenomena of Li metal and a subsequent rapid voltage drop below 1.83 V due to the complete depletion of Li at the end state of discharge. On the other hand, the voltage of the Li-Si anode cell decreased in steps, $1.93V{\rightarrow}1.72V(Li_{13}Si_4{\rightarrow}Li_7Si_3){\rightarrow}1.65V(Li_7Si_3{\rightarrow}Li_{12}Si_7)$, according to the Li-Si phase changes during the discharge reaction. The energy density of the Li anode cell was $807.1Wh\;l^{-1}$, which was about 50% higher than that of the Li-Si cell ($522.2Wh\;l^{-1}$).

• Radiation Oncology Journal
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• 제30권2호
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• pp.78-87
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• 2012

Purpose: Troglitazone (TRO) is a peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) agonist. TRO has antiproliferative activity on many kinds of cancer cells via G1 arrest. TRO also increases $Cu^{2+}/Zn^{2+}$-superoxide dismutase (CuZnSOD) and catalase. Cell cycle, and SOD and catalase may affect on radiation sensitivity. We investigated the effect of TRO on radiation sensitivity in cancer cells in vitro. Materials and Methods: Three human cervix cancer cell lines (HeLa, Me180, and SiHa) were used. The protein expressions of SOD and catalase, and catalase activities were measured at 2-10 ${\mu}M$ of TRO for 24 hours. Cell cycle was evaluated with flow cytometry. Reactive oxygen species (ROS) was measured using 2',7'-dichlorofluorescin diacetate. Cell survival by radiation was measured with clonogenic assay. Results: By 5 ${\mu}M$ TRO for 24 hours, the mRNA, protein expression and activity of catalase were increased in all three cell lines. G0-G1 phase cells were increased in HeLa and Me180 by 5 ${\mu}M$ TRO for 24 hours, but those were not increased in SiHa. By pretreatment with 5 ${\mu}M$ TRO radiation sensitivity was increased in HeLa and Me180, but it was decreased in SiHa. In Me180, with 2 ${\mu}M$ TRO which increased catalase but not increased G0-G1 cells, radiosensitization was not observed. ROS produced by radiation was decreased with TRO. Conclusion: TRO increases radiation sensitivity through G0-G1 arrest or decreases radiation sensitivity through catalase-mediated ROS scavenging according to TRO dose or cell types. The change of radiation sensitivity by combined with TRO is not dependent on the PPAR ${\gamma}$ expression level.

• 태양에너지
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• 제8권1호
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• pp.41-48
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• 1988

Heterojunction solar cells of $n-Cd_{1-x}Zn_xS/p-Si$ were fabricated by solution growth technique. The crystal structure, spectral response, surface morphology, and I-V characteristics of the $n-Cd_{1-x}Zn_xS/p-Si$ heterojunction solar cells were studied. The $Cd_{1-x}Zn_xS$ layer deposited on a silicon substrate (111) were found to be a cubic structure with the crystal orientation (111), (220) of the CdS and to be a hexagonal structure with crystal orientation (100) of the ZnS. The open-circuit voltage, short-circuit current, fill factor, and conversion efficiency of $n-Cd_{1-x}Zn_xS/p-Si$ heterojunction solar cell under $100mW/cm^2$ illumination were found to be 0.43V, 38mA. 0.76, and 12.4%, respectively.