• Korean Journal of Radiology
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• 제19권6호
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• pp.1077-1088
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• 2018

Objective: To correlate CT parameters on detector-based dual-energy CT enterography (DECTE) with Crohn's disease activity index (CDAI) and externally validate quantitative CT parameters. Materials and Methods: Thirty-nine patients with CD were retrospectively enrolled. Two radiologists reviewed DECTE images by consensus for qualitative and quantitative CT features. CT attenuation and iodine concentration for the diseased bowel were also measured. Univariate statistical tests were used to evaluate whether there was a significant difference in CTE features between remission and active groups, on the basis of the CDAI score. Pearson's correlation test and multiple linear regression analyses were used to assess the correlation between quantitative CT parameters and CDAI. For external validation, an additional 33 consecutive patients were recruited. The correlation and concordance rate were calculated between real and estimated CDAI. Results: There were significant differences between remission and active groups in the bowel enhancement pattern, subjective degree of enhancement, mesenteric fat infiltration, comb sign, and obstruction (p < 0.05). Significant correlations were found between CDAI and quantitative CT parameters, including number of lesions (correlation coefficient, r = 0.573), bowel wall thickness (r = 0.477), iodine concentration (r = 0.744), and relative degree of enhancement (r = 0.541; p < 0.05). Iodine concentration remained the sole independent variable associated with CDAI in multivariate analysis (p = 0.001). The linear regression equation for CDAI (y) and iodine concentration (x) was y = 53.549x + 55.111. For validation patients, a significant correlation (r = 0.925; p < 0.001) and high concordance rate (87.9%, 29/33) were observed between real and estimated CDAIs. Conclusion: Iodine concentration, measured on detector-based DECTE, represents a convenient and reproducible biomarker to monitor disease activity in CD.

• Journal of Microbiology and Biotechnology
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• 제34권5호
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• pp.1119-1125
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• 2024

Phytase increases the availability of phosphate and trace elements by hydrolyzing the phosphomonoester bond in phytate present in animal feed. It is also an important enzyme from an environmental perspective because it not only promotes the growth of livestocks but also prevents phosphorus contamination released into the environment. Here we present a novel phytase derived from Turicimonas muris, TmPhy, which has distinctive structure and properties compared to other previously known phytases. TmPhy gene expressed in the Pichia system was confirmed to be 41 kDa in size and was used in purified form to evaluate optimal conditions for maximum activity. TmPhy has a dual optimum pH at pH3 and pH6.8 and exhibited the highest activity at 70℃. However, the heat tolerance of the wildtype was not satisfactory for feed application. Therefore, random mutation, disulfide bond introduction, and N-terminal mutation were performed to improve the thermostability of the TmPhy. Random mutation resulted in TmPhyM with about 45% improvement in stability at 60℃. Through further improvements, a total of three mutants were screened and their heat tolerance was evaluated. As a result, we obtained TmPhyMD1 with 46.5% residual activity, TmPhyMD2 with 74.1%, and TmPhyMD3 with 66.8% at 80℃ heat treatment without significant loss of or with increased activity.

• 대한가정학회지
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• 제47권2호
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• pp.81-95
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• 2009

The purpose of this study is to examine gender equity in the quantity and flow experience of leisure time of urban dual-earner couples having preschool children. The quantity of leisure time is measured by primary activity and the flow experience of leisure time is measured by primary and secondary activities. The data collected by Korean National Statistical Office in 2004 is used. The sample for this study consists of 255 couples, and the statistical methods are frequency, percentage, paired t-test, and one-way ANOVA. The following is a summary of the major findings. The first, the pattern of the leisure time was different between husbands and wives. The quantity of leisure time of husbands was longer than that of wives. The husbands spent more time to perform social activities, media contact, sports and outdoor activities, while women did more in religious activities. The second, husband's leisure flow experience was higher than that of wives. The pure leisure time of wives was shorter than that of husbands and wives experienced more contaminated leisure time by a secondary activity. In other words, wives's leisure is more likely to be interrupted, to involve episodes of shorter duration, and to be associated with personal care and unpaid work.

• 한국발생생물학회지:발생과생식
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• 제18권4호
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• pp.225-231
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• 2014

Autophagy is a homeostatic degradation process that is involved in tumor development and normal development. Autophagy is induced in cancer cells in response to chemotherapeutic agents, and inhibition of autophagy results in enhanced cancer cell death or survival. Chloroquine (CQ), an anti-malarial drug, is a lysosomotropic agent and is currently used as a potential anticancer agent as well as an autophagy inhibitor. Here, we evaluate the characteristics of these dual activities of CQ using human colorectal cancer cell line HCT15. The results show that CQ inhibited cell viability in dose- and time-dependent manner in the range between 20 to 80 uM, while CQ did not show any antiproliferative activity at 5 and 10 uM. Cotreatment of CQ with antitumor agent NVP-BEZ235, a dual inhibitor of PI3K/mTOR, rescued the cell viability at low concentrations meaning that CQ acted as an autophagy inhibitor, but CQ induced the lethal effect at high concentrations. Acridine orange staining revealed that CQ at high doses induced lysosomal membrane permeabilization (LMP). High doses of CQ produced cellular reactive oxygen species (ROS) and cotreatment of antioxidants, such as NAC and trolox, with high doses of CQ rescued the cell viability. These results suggest that CQ may exert its dual activities, as autophagy inhibitor or LMP inducer, in concentration-dependent manner.

• Mycobiology
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• 제32권4호
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• pp.173-178
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• 2004

Fifteen Rhizobium spp. from nodules of 6 common pulses collected from 6 districts of Assam were studied for their infectivity, intrinsic antibiotic resistance, nitrogenase activity and effect of dual inoculation with two native Arbuscular Mycorrhizal Fungi viz. Glomus mosseae(GM) and Gigaspora gilmarie(GG). Out of the 15 isolates 9 were found nodulation positive and 6 of them(AR1, BR8, BR12, AR10, UR10 & GR21) were subjected to intrinsic antibiotic sensitivity test of which AR1 showed resistance against all the 9 test antibiotics. Isolates AR1 and GR21 showed the highest(4.25 mole, $gm^{-1}hour^{-1}$) and the lowest(1.05 mole, $gm^{-1}hour^{-1}$) nitrogenase activity respectively. In Most Probable Number count, the maximum Rhizobium population $5.8{\times}10^5$, was found in both Blackgram and Greengram variety of pulses. The maximum dry weight of nodules(3.14 g), dry weight of shoot(10.08 g), nitrogen content(7.68 mg, $plant^{-1}$), chlorophyll content(1.89 mg, $g^{-1}$), phosphorus content of shoot(6.17 mg, $g^{-1}$) and yield(535.67 kg, $Ha^{-1}$) were found when AR1 dually inoculated with GM in Blackgram.

• 대한전자공학회논문지SD
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• 제41권9호
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• pp.57-64
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• 2004

본 논문에서는 비동기식 회로 설계시 2선식(Dual-Rail) 코드를 사용할 때, 회로 구조에서 갖는 신호 천이를 줄여 소비전력을 감소시키는 RZ/NRZ 혼합 데이터 전송 방식을 제안한다. RZ 방식 2선식 코드는 비동기 회로 구현에 많이 사용되고 있으며, 고정 지연을 사용하는 단선구조와는 달리 데이터를 통하여 신호의 유효성을 판별할 수 있다 그러나, 단선 구조에 비해 많은 회로 면적과 모든 신호가 Return-to-Zero의 스위칭에 의해 전력 소비를 가져오므로, 신호 천이의 수를 감소시킬 필요가 있다. 본 논문에서는 RZ/NRZ 방식을 제안하여 스위칭을 약 50% 감소시키며 소비전력을 비교한 결과, 기존의 2선식에 비해 약 23% 정도 감소하는 결과를 얻었다.

• 대한화장품학회지
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• 제39권1호
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• pp.75-81
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• 2013

Chrysin (5,7-dihydroxyflavone)은 프로폴리스, 꿀 같은 음식과 다양한 식물에 존재하는 천연 플라보노이드이다. Chrysin은 항산화, 항노화, 항염, 항암 효과 등 다양한 생물학적 효과를 가진다고 알려져 있다. 이 연구에서, 우리는 사람의 각질형성세포에서 chrysin이 VDR을 통한 transcriptional activity에 미치는 영향을 dual-luciferase assay을 통하여 살펴보았다. Chrysin은 농도 의존적으로 VDR을 통한 transcriptional activity를 증가시켰다. Quantitative real time PCR을 통해 chrysin이 사람의 각질형성세포에서 VDR mRNA의 발현을 증가시킴을 확인하였다. 또한, chrysin이 각질형성세포의 분화 마커인 keratin 10, involucrin 그리고 filaggrin의 mRNA 발현을 증가시킴을 확인하였다. 이러한 연구 결과는 chrysin이 VDR을 통한 transcriptional activity를 조절하여 각질형성세포의 분화를 촉진시킬 수 있다는 것을 시사한다.

• 한국연초학회지
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• 제16권2호
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• pp.144-151
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• 1994

Using a flue-cured tobacco variety, BU 109, effect of growth regulators(Fatty Alcohol and C-MH) on the change of invertase activity and sugar metabolites were investigated. Invertase activity in untreated leaf tissue was decreased along with maturation of leaf, However, a momentary increase of the activity was observed in leaves by the dual treatment of fatty alcohol and C-MH regardless of leaf position while sole C-MH treatment resulted in activity increase by 14 days after the treatment. Similar tendency was observed in stalk. Sugar content in leaf was increased immediately after the treatment but no significant increase at large resulted until 14 days after treatment. After harvest, reducing sugar was increased by the growth regulators. Nevertheless, in case of dual treatment, the total sugar content was not different with that of untreated control. R/T ratio was gradually increased after topping stage and reached maximum at 14 days after treatment of growth regulators. It decreased a little after harvest but the RR ratio was relatively higher due to increase of reducing sugar resulted by the treatment of the chemicals. Upon treatment of growth regulators, reducing sugar content was increased in lugs and leaves compared to untreated control and the content of sugar metabolites was increased by the use of the chemicals either at lower or higher than recommended dose. Key words : MH, FA, invertase activity, total sugar, reducing sugar

• Korean Chemical Engineering Research
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• 제46권1호
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• pp.82-87
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• 2008

Methane의 부분산화에 의하여 일산화탄소를 발생시키고 이를 이용하여 온실가스로 알려져 있는 $N_2O$를 분해시키기 위한 이중 촉매 반응시스템의 반응 특성을 살펴보았다. 일산화탄소를 발생시키기 위한 제1 반응기의 조건은 Co-Rh-Al (1/0.2/1) 촉매를 사용할 때 $500^{\circ}C$의 온도에서 methane과 산소의 비율이 5:1이고 GHSV $8,000h^{-1}$ 일때 가장 적합하였다. 제1 반응기에서 methane을 부분산화시켜 얻은 혼합 가스를 사용하는 이중 반응시스템에서 제2 반응기에 촉매로 Co-Rh-Al(1/0.2/1)과 Co-Rh-Zr-Al(1/0.2/0.3/1)을 사용한 경우 Co-Rh-Al(1/0.2/1) 촉매를 사용한 single bed system 보다 $250^{\circ}C$ 이하의 저온에서 우수한 분해성능을 나타내었다. 두 경우 모두 $250^{\circ}C$ 이상의 온도에서는 $N_2O$가 100% 분해되었다. 또한, 제2 반응기에서 $N_2O$ 분해성능은 NO의 존재 유무에 관계없이 산소의 농도가 증가할수록 감소함을 보여주었다. 다만 NO가 존재할 경우 산소의 농도가 10,000 ppm 이하일 때 100% 분해율을 보이며 그 이상일 경우 급격히 감소하였다.

• BMB Reports
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• 제53권6호
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• pp.335-340
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• 2020

Since cancer is the leading cause of death worldwide, there is an urgent need to understand the mechanisms underlying cancer progression and the development of cancer inhibitors. Signal transducer and activator of transcription 3 (STAT3) is a major transcription factor that regulates the proliferation and survival of various cancer cells. Here, dual-specificity phosphatase 3 (DUSP3) was identified as a regulator of STAT3 based on an interaction screening performed using the protein tyrosine phosphatase library. DUSP3 interacted with the C-terminal domain of STAT3 and dephosphorylated p-Y705 of STAT3. In vitro dephosphorylation assay revealed that DUSP3 directly dephosphorylated p-STAT3. The suppressive effects of DUSP3 on STAT3 were evaluated by a decreased STAT3-specific promoter activity, which in turn reduced the expression of the downstream target genes of STAT3. In summary, DUSP3 downregulated the transcriptional activity of STAT3 via dephosphorylation at Y705 and also suppressed the migratory activity of cancer cells. This study demonstrated that DUSP3 inhibits interleukin 6 (IL-6)/STAT3 signaling and is expected to regulate cancer development. Novel functions of DUSP3 discovered in IL-6/STAT3 signaling regulation would help expand the understanding of cancer development mechanisms.