250 results on '"Hwang, Kyung-A"'
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102. Symmetric Identities for Carlitz-Type Higher-Order Degenerate (p,q)-Euler Numbers and Polynomials.
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Hwang, Kyung-Won and Ryoo, Cheon Seoung
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POLYNOMIALS , *EULER polynomials , *EULER number - Abstract
The main goal of this paper is to investigate some interesting symmetric identities for Carlitz-type higher-order degenerate (p , q) -Euler numbers, and polynomials. At first, the Carlitz-type higher-order degenerate (p , q) -Euler numbers and polynomials are defined. We give few new symmetric identities for Carlitz-type higher-order degenerate (p , q) -Euler numbers and polynomials. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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103. Some Properties for Multiple Twisted (p, q)-L-Function and Carlitz's Type Higher-Order Twisted (p, q)-Euler Polynomials.
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Hwang, Kyung-Won and Ryoo, Cheon Seoung
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EULER polynomials , *POLYNOMIALS , *GENERATING functions , *INTEGRAL representations , *ZETA functions - Abstract
The main goal of this paper is to study some interesting identities for the multiple twisted (p , q) -L-function in a complex field. First, we construct new generating functions of the new Carlitz-type higher order twisted (p , q) -Euler numbers and polynomials. By applying the Mellin transformation to these generating functions, we obtain integral representations of the multiple twisted (p , q) -Euler zeta function and multiple twisted (p , q) -L-function, which interpolate the Carlitz-type higher order twisted (p , q) -Euler numbers and Carlitz-type higher order twisted (p , q) -Euler polynomials at non-positive integers, respectively. Second, we get some explicit formulas and properties, which are related to Carlitz-type higher order twisted (p , q) -Euler numbers and polynomials. Third, we give some new symmetric identities for the multiple twisted (p , q) -L-function. Furthermore, we also obtain symmetric identities for Carlitz-type higher order twisted (p , q) -Euler numbers and polynomials by using the symmetric property for the multiple twisted (p , q) -L-function. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
104. Effects of Fludioxonil on the Cell Growth and Apoptosis in T and B Lymphocytes.
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Lee, Gun-Hwi, Hwang, Kyung-A, and Choi, Kyung-Chul
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T cells , *CELL growth , *CELL survival , *B cells , *APOPTOSIS , *HUMAN T cells , *BCL-2 proteins - Abstract
Fludioxonil is fungicide used in agriculture, which is present in fruits and vegetables. In this study, the effects of fludioxonil on human immune cell viability, apoptosis, cell cycle arrest, and mitochondrial membrane potential were examined in human immune cells, such as Jurkat T cells and Ramos B cells. To examine the cell viability, Jurkat T cells and Ramos B cells were treated with fludioxonil (10−9–10−5 M) for 24 h and 48 h. Water soluble tetrazolium salt assay showed that fludioxonil decreased Jurkat T cell and Ramos B cell viability. Jurkat T cell viability decreased at 24 and 48 h, but Ramos B cell viability decreased only at 48 h. JC-1 dye revealed decreased mitochondrial membrane potential in fludioxonil-treated Jurkat T cells and Ramos B cells. To evaluate apoptosis, annexin-V conjugated FITC, AF488, and propidium iodide (PI) were used and to evaluate cell cycle arrest PI was used. Apoptosis and cell cycle arrest were induced by fludioxonil (10−7–10−5 M) in the Jurkat T cells at 24 and 48 h and Ramos B cells at 48 h. Moreover, the protein levels of pro-apoptotic proteins, such as p53, BAX, and cleaved caspase 3, were increased and anti-apoptotic protein Bcl-2 was decreased by fludioxonil. Expression of the Fas receptor related to the extrinsic apoptosis pathway was increased by fludioxonil. Additionally, cyclin D1 and cyclin E1 were decreased by fludioxonil. In the present study, fludioxonil induced immunotoxicity in human T cells and B cells through apoptosis and cell cycle arrest. Therefore, the present study suggests that fludioxonil induces the cellular toxicity in immune cells. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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105. Differential Equations Arising from the Generating Function of the (r, β)-Bell Polynomials and Distribution of Zeros of Equations.
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Hwang, Kyung-Won, Ryoo, Cheon Seoung, and Jung, Nam Soon
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GENERATING functions , *DIFFERENTIAL equations , *POLYNOMIALS , *IDENTITIES (Mathematics) , *EQUATIONS - Abstract
In this paper, we study differential equations arising from the generating function of the (r , β) -Bell polynomials. We give explicit identities for the (r , β) -Bell polynomials. Finally, we find the zeros of the (r , β) -Bell equations with numerical experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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106. Eligibility and Cost-Utility Analysis of Dapagliflozin in Patients with Heart Failure Across the Whole Spectrum of Ejection Fraction in South Korea.
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Kim, Eui-Soon, Park, Sun-Kyeong, Cho, Daniel Sung-ho, Youn, Jong-Chan, Lee, Hye Sun, Lee, Hae-Young, Cho, Hyun-Jai, Choi, Jin-Oh, Jeon, Eun-Seok, Lee, Sang Eun, Kim, Min-Seok, Kim, Jae-Joong, Hwang, Kyung-Kuk, Cho, Myeong-Chan, Chae, Shung Chull, Kang, Seok-Min, Park, Jin Joo, Choi, Dong-Ju, Yoo, Byung-Su, and Cho, Jae Yeong
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STATISTICAL models , *VENTRICULAR ejection fraction , *COST effectiveness , *RESEARCH funding , *DAPAGLIFLOZIN , *HEART failure , *COST benefit analysis , *DESCRIPTIVE statistics , *ELIGIBILITY (Social aspects) , *MEDICAL care costs , *COMORBIDITY - Abstract
Background: The DAPA-HF and DELIVER trials demonstrated the clinical benefits of dapagliflozin in heart failure (HF) patients across the entire ejection fraction (EF) spectrum. However, further investigation is needed for the real-world application of dapagliflozin in HF patients. This study examines the proportion of real-world HF patients eligible for dapagliflozin and evaluates the cost-effectiveness of adding dapagliflozin to current HF therapy. Methods: Data from the nationwide prospective registry, the Korean Acute Heart Failure (KorAHF) registry, were used to determine dapagliflozin eligibility based on the enrollment criteria of the DAPA-HF/DELIVER trials. A cost-utility analysis was conducted using a Markov model to assess the cost-effectiveness of dapagliflozin by comparing it to the standard of care. Results: Out of 5178 KorAHF patients, 48.7% met the enrollment criteria of the DAPA-HF/DELIVER trials, while 89.5% met the label criteria (US Food and Drug Administration, European Medicines Agency, and Korean Ministry of Food and Drug Safety). Eligibility was highest among HF patients with preserved EF (55.3% vs. HF with mildly reduced EF and HF with reduced EF 46.4%). Dapagliflozin proved to be cost-effective, with an incremental cost-effectiveness ratio (ICER) of 4557 US dollar (US$) per quality-adjusted life year, which falls below the US$18,182 willingness-to-pay threshold. The cost-effectiveness benefit was more pronounced in patients with a left ventricular EF (LVEF) ≤ 40% (ICER US$3279 for LVEF ≤ 40% vs. US$8383 for LVEF > 40%). Conclusions: Discrepancies in dapagliflozin eligibility were observed between real-world data and clinical trial results. The addition of dapagliflozin to HF therapy proved to be highly cost-effective across the entire EF spectrum. [ABSTRACT FROM AUTHOR]
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- 2024
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107. Association between body mass index and three-year outcome of acute myocardial infarction.
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Park, Soyoon, Kim, Dae-Won, Lee, Kyusup, Park, Mahn-Won, Chang, Kiyuk, Jeong, Myung Ho, Ahn, Young Keun, Chae, Sung Chull, Ahn, Tae Hoon, Rha, Seung Woon, Kim, Hyo-Soo, Gwon, Hyeon Cheol, Seong, In Whan, Hwang, Kyung Kuk, Kim, Kwon-Bae, Cha, Kwang Soo, Oh, Seok Kyu, and Chae, Jei Keon
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BODY mass index , *OBESITY paradox , *PERCUTANEOUS coronary intervention - Abstract
Body mass index (BMI), as an important risk factor related to metabolic disease. However, in some studies higher BMI was emphasized as a beneficial factor in the clinical course of patients after acute myocardial infarction (AMI) in a concept known as the "BMI paradox." The purpose of this study was to investigate how clinical outcomes of patients treated for AMI differed according to BMI levels. A total of 10,566 patients in the Korea Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH) from May 2010 to June 2015 were divided into three BMI groups (group 1: BMI < 22 kg/m2, group 2: ≥ 22 and < 26 kg/m2, and group 3: ≥ 26 kg/m2). The primary outcome was major adverse cardiac and cerebrovascular event (MACCE) at 3 years of follow-up. At 1 year of follow-up, the incidence of MACCE in group 1 was 10.1% of that in group 3, with a hazard ratio (HR) of 2.27, and 6.5% in group 2, with an HR of 1.415. This tendency continued up to 3 years of follow-up. The study demonstrated that lower incidence of MACCE in the high BMI group of Asians during the 3-year follow-up period compared to the low BMI group. The results implied higher BMI could exert a positive effect on the long-term clinical outcomes of patients with AMI undergoing percutaneous coronary intervention (PCI). [ABSTRACT FROM AUTHOR]
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- 2024
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108. Understanding the effect of co-reactants on ketonization of carboxylic acids in the aqueous-phase pyrolysis oil of wood.
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Choi, Il-Ho, Lee, Hye-Jin, and Hwang, Kyung-Ran
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CARBOXYLIC acids , *FURFURAL , *PYROLYSIS , *ACETIC acid , *HYDROXYPROPANONE , *CATALYTIC activity , *WOOD - Abstract
Ketonization of carboxylic acids is one of the crucial reactions to produce sustainable bio-fuel and bio-chemicals from the pyrolysis oil of wood. Ketonization using different mixed solutions of carboxylic acids, furfural, and hydroxyacetone has been explored to understand the influence of co-feed reactants on the performance of ketonization of carboxylic acid over the selected CeZrOx catalyst. Furfural (7% in water) inhibited the catalytic activity for ketonization of acetic acid (20% solution) with reversible blocking of active sites, but for a mixed solution of hydroxyacetone (7%) and acetic acid (20%), both reactants influenced each other, resulting in very low conversions and slow and uncompleted recovery to 50% after removing hydroacetone from the mixture. For the mixed solution (20% acetic acid + 7% furfural + 7% hydroxyacetone in water), hydroxyacetone was the most reactive compound on CeZrOx and the conversions of reactants reached below 10%, due to the inhibition of co-existing carbonyl components. This work provides guidance for ketonization of carboxylic acids in the aqueous-phase pyrolysis oil. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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109. Rules of the House: Family Law and Domestic Disputes in Colonial Korea.
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Hwang, Kyung Moon
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DOMESTIC relations , *NONFICTION ,JAPANESE occupation of Korea, 1910-1945 - Published
- 2019
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110. Some Symmetric Identities for Degenerate Carlitz-type (p, q)-Euler Numbers and Polynomials.
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Hwang, Kyung-Won and Ryoo, Cheon Seoung
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EULER polynomials , *EULER number , *POLYNOMIALS , *EULER characteristic - Abstract
In this paper we define the degenerate Carlitz-type (p , q) -Euler polynomials by generalizing the degenerate Euler numbers and polynomials, degenerate Carlitz-type q-Euler numbers and polynomials. We also give some theorems and exact formulas, which have a connection to degenerate Carlitz-type (p , q) -Euler numbers and polynomials. [ABSTRACT FROM AUTHOR]
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- 2019
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111. Some Symmetric Identities for the Multiple (p, q)-Hurwitz-Euler eta Function.
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Hwang, Kyung-Won and Ryoo, Cheon Seoung
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EULER polynomials , *IDENTITIES (Mathematics) , *EULER number , *POLYNOMIALS - Abstract
The main purpose of this paper is to find some interesting symmetric identities for the (p , q) -Hurwitz-Euler eta function in a complex field. Firstly, we define the multiple (p , q) -Hurwitz-Euler eta function by generalizing the Carlitz's form (p , q) -Euler numbers and polynomials. We find some formulas and properties involved in Carlitz's form (p , q) -Euler numbers and polynomials with higher order. We find new symmetric identities for multiple (p , q) -Hurwitz-Euler eta functions. We also obtain symmetric identities for Carlitz's form (p , q) -Euler numbers and polynomials with higher order by using symmetry about multiple (p , q) -Hurwitz-Euler eta functions. Finally, we study the distribution and symmetric properties of the zero of Carlitz's form (p , q) -Euler numbers and polynomials with higher order. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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112. Connection Problem for Sums of Finite Products of Legendre and Laguerre Polynomials.
- Author
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Kim, Taekyun, Hwang, Kyung-Won, Kim, Dae San, and Dolgy, Dmitry V.
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LAGUERRE polynomials , *GEGENBAUER polynomials , *ORTHOGONAL polynomials , *JACOBI polynomials , *HYPERGEOMETRIC functions - Abstract
The purpose of this paper is to represent sums of finite products of Legendre and Laguerre polynomials in terms of several orthogonal polynomials. Indeed, by explicit computations we express each of them as linear combinations of Hermite, generalized Laguerre, Legendre, Gegenbauer and Jacobi polynomials, some of which involve terminating hypergeometric functions 1 F 1 and 2 F 1 . [ABSTRACT FROM AUTHOR]
- Published
- 2019
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113. Examining the Use, Perception, and Motivation of Cord-Cutting: A Consumer Segment Approach.
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Kim, Hun, Chan-Olmsted, Sylvia M., Hwang, Kyung-Ho, and Chang, Byeng-Hee
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CABLE television subscription cancellations , *CABLE television viewers , *CABLE television , *CABLE television industry , *SENSORY perception , *MOTIVATION (Psychology) - Abstract
This study investigates the factors affecting the cord-cutting behavior of media consumers. Adopting the frameworks of diffusion of innovations, uses and gratifications theory (U&G), channel repertoire, and media usage/segmentation, we conducted an online survey of 860 respondents in the United States to examine the use, perception, and motivation of cord-cutting behavior among three different consumer segments: cord-cutters, cord-loyalists, and cord-couplers. The results show that cord-cutting is predicted by eudaimonic and exploration motivators, perceived compatibility and complementarity, and age. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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114. Critical Point Drying: An Effective Drying Method for Direct Measurement of the Surface Area of a Pretreated Cellulosic Biomass.
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Kang, Kyu-Young, Hwang, Kyung-Ran, Park, Ji-Yeon, Lee, Joon-Pyo, Kim, Jun-Seok, and Lee, Jin-Suk
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PORE size distribution , *CELLULOSIC ethanol , *CRITICAL point (Thermodynamics) , *BIOMASS , *HYDROGEN bonding - Abstract
The surface area and pore size distribution of
Eucalyptus samples that were pretreated by different methods were determined by the Brunauer–Emmett–Teller (BET) technique. Three methods were applied to prepare cellulosic biomass samples for the BET measurements, air, freeze, and critical point drying (CPD). The air and freeze drying caused a severe collapse of the biomass pore structures, but the CPD effectively preserved the biomass morphology. The surface area of the CPD preparedEucalyptus samples were determined to be 58–161 m2/g, whereas the air and freeze dried samples were 0.5–1.3 and 1.0–2.4 m2/g, respectively. The average pore diameter of the CPD preparedEucalyptus samples were 61–70 Å. The CPD preserved theEucalyptus sample morphology by replacing water with a non-polar solvent, CO2 fluid, which prevented hydrogen bond reformation in the cellulose. [ABSTRACT FROM AUTHOR]- Published
- 2018
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115. Catalytic steam reforming of glycerol over Ni–La2O3–CeO2/SBA-15 catalyst for stable hydrogen-rich gas production.
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Moogi, Surendar, Lee, In-Gu, and Hwang, Kyung-Ran
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CATALYSTS , *NICKEL catalysts , *STEAM reforming , *CATALYTIC reforming , *MESOPOROUS silica , *GLYCERIN , *TRANSMISSION electron microscopy - Abstract
Ni-based catalysts (Ni, Ni–La 2 O 3 , and Ni–La 2 O 3 –CeO 2) on mesoporous silica supports (SBA-15 and KIT-6) were prepared by an incipient wetness impregnation and tested in glycerol steam reforming (GSR) for hydrogen-rich gas production. The catalysts were characterized by the N 2 -physisorption, TPD, X-ray diffraction (XRD), SEM-EDS, and TEM techniques. N 2 -physisorption results of calcined catalysts highlight that adding of La 2 O 3 increased surface area of the catalyst by preventing pore mouth plugging in SBA-15, which was frequently observed due to the growth of NiO crystals. A set of GSR experiments over the catalysts were performed in an up-flow continuous packed-bed reactor at 650 °C and atmospheric pressure. The highest hydrogen concentration of 62 mol% was observed with a 10%Ni–5%La 2 O 3 –5%CeO 2 /SBA-15 catalyst at a LHSV of 5.8 h−1. Adding of CeO 2 to the catalyst appeared to increase catalytic stability by facilitating the oxidative gasification of carbon formed on/near nickel active sites of Ni–La 2 O 3 –CeO 2 /SBA-15 and Ni–La 2 O 3 –CeO 2 /KIT-6 catalyst during the glycerol steam reforming reaction. Image 1 • Ni-based catalysts on mesoporous silica were prepared for GSR reaction. • Adding of La 2 O 3 to Ni/SBA-15 catalyst suppressed crystalline growth of Ni. • Adding of CeO 2 to Ni–La 2 O 3 /SBA-15 catalyst facilitate carbon removal. • 10% Ni–5%La 2 O 3 –5%CeO 2 /SBA-15 catalyst showed the highest hydrogen yield. [ABSTRACT FROM AUTHOR]
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- 2020
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116. Characterization of canine adipose tissue‐derived mesenchymal stem cells immortalized by SV40‐T retrovirus for therapeutic use.
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Ayala‐Cuellar, Ana Patricia, Kim, Cho‐Won, Hwang, Kyung‐A, Kang, Ji‐Houn, Lee, Gabsang, Cho, Jaejin, and Choi, Kyung‐Chul
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MESENCHYMAL stem cells , *ADIPOSE tissues , *STEM cells , *CELL lines - Abstract
Canine mesenchymal stem cells (cMSCs) are gaining popularity in the veterinary field as a regenerative therapy. But, their limited culture lifespan makes it an obstacle for preclinical investigation and therapeutic use. In this study, primary canine adipose tissue‐derived MSCs (PCAT‐MSCs) were isolated from adipose tissue and were transfected with the SV40‐T retrovirus resulting in a life‐extended immortalized canine adipose tissue‐derived MSCs (ICAT‐MSCs). A comparison was made through the characterization of both PCAT‐MSCs and ICAT‐MSCs. Both showed a fibroblastic morphology; ICAT‐MSCs showed a higher potential of colony formation compared with PCAT‐MSCs and a reduced population doubling time; stem cell markers SOX2 and NANOG were expressed in both cell lines; karyotyping analysis showed no abnormalities in both PCAT‐MSCs and ICAT‐MSCs; both cell lines were CD90+, CD44 +, and CD45 −; both generated chondrogenic pellet; in osteogenic differentiation both showed upregulation of Osterix, a master transcriptome of osteogenesis, but in PCAT‐MSCs, an upregulation of SOX2 was also observed. In conclusion, ICAT‐MSCs showed similar characteristics with PCAT‐MSCs, thus established as an easy to access platform for studies on better understanding about cMSCs nature. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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117. Effects of cigarette smoke extracts on apoptosis and oxidative stress in two models of ovarian cancer in vitro.
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Kim, Cho-Won, Go, Ryeo-Eun, Hwang, Kyung-A, Bae, Ok-Nam, Lee, Kyuhong, and Choi, Kyung-Chul
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PHYSIOLOGICAL effects of tobacco , *WOMEN'S health , *CANCER cells , *OXIDATIVE stress , *APOPTOSIS - Abstract
Abstract Cigarette smoke contains thousands of harmful components, many of which exert toxic effects on reproductive organs, including the ovaries, and their development. In this study, we investigated the effects of cigarette smoke extract (CSE) on cell proliferation, apoptosis and oxidative stress in the SKOV3 and OVCAR3 ovarian cancer cell lines. A water soluble tetrazolium (WST) assay revealed that the cell proliferation of both ovarian cells was significantly inhibited by three types of CSE in a concentration-dependent manner. Western blot analysis showed that the inhibition of cell proliferation was related to regulation of cell cycle-related protein expression. To determine the effects of cigarette smoke on the death of ovarian cells, we conducted a TUNEL assay, which revealed a time-dependent increase in TUNEL-stained cells in response to CSE exposure. Moreover, the protein expression of the Bcl-2 family signaling pathway observed upon Western blot analysis were consistent with the results of the TUNEL assay. We also examined the reactive oxygen species (ROS) generation in two ovarian cell lines using DCF-DA (5(6)-Carboxy-2′,7′-dichlorofluorescein diacetate) assay and ROS-Glo™ H 2 O 2 assay to investigate the oxidative stress caused by CSE. Both ROS detection assays demonstrated an increase in the amount of ROS by CSE in ovarian cells, which was consistent with the results observed for the Keap1-Nrf2 pathway upon Western blot analysis. Taken together, these results suggest that CSE may induce cell proliferation inhibition and oxidative stress in ovarian cells. Highlights • Cigarette smoke extract (CSE) may inhibit the cell proliferation. • CSE can induce cell death by regulating Bcl-2 family in ovarian cancer. • CSE induced oxidative stress by increasing ROS in ovarian cancer. • CSE induced ROS by regulating Keap1-Nrf2 pathway. • CSE may exert cytotoxicity by inducing oxidative stress and apoptosis. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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118. Effects of Conventional Synthetic Disease-Modifying Antirheumatic Drugs on Response to Periodontal Treatment in Patients with Rheumatoid Arthritis.
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Jung, Gyu-Un, Han, Ji-Young, Hwang, Kyung-Gyun, Park, Chang-Joo, Stathopoulou, Panagiota G., and Fiorellini, Joseph P.
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METHOTREXATE , *NONSTEROIDAL anti-inflammatory agents , *STEROID drugs , *CHLOROQUINE , *ANTIRHEUMATIC agents , *SULFONAMIDES , *DENTAL scaling , *HEMORRHAGE , *LONGITUDINAL method , *PERIODONTITIS , *RHEUMATOID arthritis , *STATISTICS , *TOOTH root planing , *DATA analysis , *TREATMENT effectiveness , *SEVERITY of illness index , *THERAPEUTICS - Abstract
Rheumatoid arthritis (RA) and periodontitis are common chronic inflammatory diseases and periodontitis is known to be more common and more severe in patients with RA. Based on a paucity of studies about the relationship between common conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and periodontitis, this prospective study aimed to evaluate the adjunctive effect of csDMARDs on response to nonsurgical periodontal treatment in patients with RA. Thirty-two patients with RA (RA group) and 32 systemically healthy patients (control group) with periodontitis were included in this study. The RA group patients were treated with csDMARDs, such as methotrexate, hydroxychloroquine, and sulfasalazine. Conventional nonsurgical periodontal treatment with scaling and root planing was performed in both groups. The extent and severity of periodontitis were evaluated by plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) at baseline and 4 weeks after periodontal treatment. There was no statistically significant difference of periodontal parameters between the RA and control groups at baseline. Four weeks after scaling and root planing, PD reduction, and CAL gain were higher in the RA group treated with csDMARDs compared to the control group, and the difference was statistically significant (P = 0.006 and 0.003, respectively). A post hoc analysis of the RA group showed no statistically significant difference on the response to nonsurgical periodontal treatment in multiple csDMARDs therapy and addition of NSAIDs and/or steroids to csDMARDs. In patients with RA, csDMARDs showed beneficial effect on periodontal clinical parameters following the nonsurgical periodontal treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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119. Correction: Light-penetration and light-scattering effects in dye-sensitised solar cells.
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Hwang, Kyung-Jun, Kim, Dajung, Park, Ju-Young, An, Jongdeok, Jin, Sungho, Kang, Sang Ook, Cho, Dae Won, and Im, Chan
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LIGHT scattering , *DYE-sensitized solar cells - Abstract
Correction for ‘Light-penetration and light-scattering effects in dye-sensitised solar cells’ by Kyung-Jun Hwang et al., New J. Chem., 2014, 38, 6161–6167. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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120. Correlation between depressive symptoms and subjective mastication ability and ability to pronunciation among Korean elderly.
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Park, Min Sun, Hwang, Kyung-Gyun, and Choi, Bo Youl
- Abstract
Objectives: The present study examines the relationship between depressive symptoms and subjective chewing and pronunciation ability in Korean seniors. Our goal is to provide the data required to develop appropriate oral health interventions programs for seniors.Methods: The Center for Epidemiologic Studies-Depression Scale (CES-D) is widely used depressive symptoms assessment. A Korean version was used for the 2009 Community Health Survey, which was consulted to extract the present study's participants comprising 50,694 Korean seniors (males, 20,582; females, 30,112) aged ≥65 years. Those with a CES-D score ≥16 were rated 'depressed.' SAS version 9.3 was used for the data analysis.Results: Prevalence of depressive symptoms increased as the participants socioeconomic status decreased, number of health issues increased, health behavior worsened, and chewing and pronunciation discomfort increased. Males with chewing difficulties were found to have 1.45 times (95% confidence interval [CI], 1.29 to 1.63) greater risk of depressive symptoms than those without, while males with pronunciation discomfort were found to have 1.97 times greater risk of depressive symptoms than those without (95% CI, 1.76 to 2.20). Females with chewing difficulty were found to have 1.50 times (95% CI, 1.39 to 1.61) greater risk of depressive symptoms than those without, and females with pronunciation discomfort were found to have 1.55 times greater risk of depressive symptoms than those without (95% CI, 1.44 to 1.67).Conclusions: Intervention programs designed to help with oral health management and alleviate depressive symptoms in seniors are urgently needed. As the prevalence of depressive symptoms may vary geographically, research examining potential variance at city, district, and town levels would be beneficial. [ABSTRACT FROM AUTHOR]- Published
- 2016
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121. A note on convex subsets of
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Hwang, Kyung-Won and Sheikh, Naeem N.
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CONVEX sets , *INTERSECTION theory , *INTEGERS , *CARDINAL numbers , *MAXIMA & minima , *DIMENSIONS , *LATTICE theory - Abstract
Abstract: R. Graham, M. Simonovits, and V.T. Sós [R. Graham, M. Simonovits, V.T. Sós, A note on the intersection properties of subsets of integers, J. Combin. Theory, Ser. A 28 (1980) 106–110] in 1980 posed the following question. Suppose is a convex subset of and let be a family of subsets of such that is convex and nonempty for . If is a family of maximum cardinality with this property, is it true that is also non-empty? In this paper, we answer this question in the negative by exhibiting a set, , and a family of subsets of for every dimension . [Copyright &y& Elsevier]
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- 2009
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122. The impact of angiotensin-converting-enzyme inhibitors versus angiotensin receptor blockers on 3-year clinical outcomes in elderly (≥ 65) patients with acute myocardial infarction without hypertension.
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Ahn, Woo Jin, Rha, Seung-Woon, Choi, Byoung Geol, Jeong, Myung Ho, Ahn, Tae Hoon, Yoon, Junghan, Kim, Hyo‐Soo, Seung, Ki‐Bae, Gwon, Hyeon‐Cheol, Chae, Shung Chull, Kim, Chong‐Jin, Cha, Kwang Soo, Lee, Jung‐Hee, Chae, Jei Keon, Joo, Seung‐Jae, Yoon, Chang‐Hwan, Hur, Seung‐Ho, Seong, In‐Whan, Hwang, Kyung‐Kuk, and Kim, Doo‐Il
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ANGIOTENSIN-receptor blockers , *MYOCARDIAL infarction , *MAJOR adverse cardiovascular events , *OLDER patients , *PERCUTANEOUS coronary intervention , *OLDER people - Abstract
Objective: This study aimed to investigate the impact of angiotensin-converting-enzyme inhibitors (ACEI) and angiotensin II type 1 receptor blockers (ARB) on 3-year clinical outcomes in elderly (≥ 65) acute myocardial infarction (AMI) patients without a history of hypertension who underwent successful percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: A total of 13,104 AMI patients who were registered in the Korea AMI registry (KAMIR)-National Institutes of Health (NIH) were included in the study. The primary endpoint was 3-year major adverse cardiac events (MACE), which was defined as the composite of all-cause death, recurrent myocardial infarction (MI), and any repeat revascularization. To adjust baseline potential confounders, an inverse probability weighting (IPTW) analysis was performed. Results: The patients were divided into two groups: the ACEI group, n = 872 patients and the ARB group, n = 508 patients. After IPTW matching, baseline characteristics were balanced. During the 3-year clinical follow-up, the incidence of MACE was not different between the two groups. However, incidence of stroke (hazard ratio [HR], 0.375; 95% confidence interval [CI], 0.166–0.846; p = 0.018) and re-hospitalization due to heart failure (HF) (HR, 0.528; 95% CI, 0.289–0.965; p = 0.038) in the ACEI group were significantly lower than in the ARB group. Conclusion: In elderly AMI patients who underwent PCI with DES without a history of hypertension, the use of ACEI was significantly associated with reduced incidences of stroke, and re-hospitalization due to HF than those with the use of ARB. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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123. Heterologous vaccination utilizing viral vector and protein platforms confers complete protection against SFTSV.
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Kim, Jae-Yong, Jeon, Kyeongseok, Hong, Jung Joo, Park, Sang-In, Cho, Hyeonggon, Park, Hyo-Jung, Kwak, Hye Won, Park, Hyeong-Jun, Bang, Yoo-Jin, Lee, Yu-Sun, Bae, Seo-Hyeon, Kim, So-Hee, Hwang, Kyung-Ah, Jung, Dae-Im, Cho, Seong Hoo, Seo, Sang Hwan, Kim, Green, Oh, Hanseul, Lee, Hwal-Yong, and Kim, Ki Hyun
- Subjects
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GENETIC vectors , *VIRAL proteins , *EMERGING infectious diseases , *FEVER , *VACCINATION , *ANTIBODY titer , *T cells - Abstract
Severe fever with thrombocytopenia syndrome virus was first discovered in 2009 as the causative agent of severe fever with thrombocytopenia syndrome. Despite its potential threat to public health, no prophylactic vaccine is yet available. This study developed a heterologous prime-boost strategy comprising priming with recombinant replication-deficient human adenovirus type 5 (rAd5) expressing the surface glycoprotein, Gn, and boosting with Gn protein. This vaccination regimen induced balanced Th1/Th2 immune responses and resulted in potent humoral and T cell-mediated responses in mice. It elicited high neutralizing antibody titers in both mice and non-human primates. Transcriptome analysis revealed that rAd5 and Gn proteins induced adaptive and innate immune pathways, respectively. This study provides immunological and mechanistic insight into this heterologous regimen and paves the way for future strategies against emerging infectious diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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124. Book Review: A Family of No Prominence: The Descendants of Pak Tŏkhwa and the Birth of Modern Korea.
- Author
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Hwang, Kyung Moon
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FAMILIES , *NONFICTION , *KOREAN history - Published
- 2015
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125. Cigarette smoke impaired maturation of ovarian follicles and normal growth of uterus inner wall of female wild-type and hypertensive rats.
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Lee, Hae-Miru, Kim, Cho-Won, Hwang, Kyung-a., Sung, Jae-Hyuck, Lee, Jin-Kyu, and Choi, Kyung-Chul
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CIGARETTE smoke , *OVARIAN follicle , *UTERUS , *ENDOPLASMIC reticulum , *HYPERTENSION , *PATIENTS - Abstract
Cigarette smoke (CS) is well known to be very harmful to human body functions such as fertility, reproduction, and development. CS is considered to more affect patients with hypertension (HT). To estimate the effect of CS associated with female rat’s fertility, we examined the histopathological characteristics of the uterus and ovary which were obtained from the female rats exposed to smoke of the standard cigarette (3R4F) for 4 weeks (10 h a week) according to the OECD guidelines. The female wild-type Wistar Kyoto (WK) rats (WTR) and spontaneously hypertensive WK rats (SHR) were used to compare the effect of CS on healthy and hypertensive rats. After CS exposure, we manufactured tissue slides from uterine and ovarian samples and evaluated the maturation of follicles of ovary and cell proliferation in the uterus by H&E staining and immunohistochemistry (IHC). In IHC analysis on ovarian tissues, the expression of proliferating cell nuclear antigen (PCNA) and the number of follicles were decreased by CS exposure. On the contrary, PCNA expression and cell proliferation in the uterine inner layers were increased by CS exposure. The protein expression of C/EBP homologous protein (CHOP), an endoplasmic reticulum (ER)-stress marker, and BAX, a pro-apoptotic protein, was decreased by CS exposure. This phenomenon was more exacerbated in SHR rats than in WTR rats. Taken together, acute exposure to CS induced the decreased maturation of ovarian follicles and abnormal over-growth of uterine inner wall, leading to a harmful effect on female rat’s normal function. In addition, this harmful effect of CS may be displayed more seriously in rats with HT. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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126. Benzo(a)pyrene induced cell cycle arrest and apoptosis in human choriocarcinoma cancer cells through reactive oxygen species-induced endoplasmic reticulum-stress pathway.
- Author
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Kim, Soo-Min, Lee, Hae-Miru, Hwang, Kyung-A., and Choi, Kyung-Chul
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BENZOPYRENE , *APOPTOSIS , *CHORIOCARCINOMA , *REACTIVE oxygen species , *ENDOPLASMIC reticulum , *PHYSIOLOGICAL stress - Abstract
Cigarette smoke (CS) contains over 60 well established carcinogens. In this study, we examined the effects of benzo(a)pyrene (B(a)P), a main CS component, on the viability and apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cell lines. An MTT assay confirmed that B(a)P decreased the cell viability of JEG-3 and BeWo cells in a dose-dependent manner. Additionally, Western blot (WB) assay revealed that protein expression of cyclin D and cyclin E decreased, while protein expression of p21 and p27 was increased in response to B(a)P treatment for 48 h. The changes in reactive oxygen species (ROS) levels in JEG-3 and BeWo cells exposed to B(a)P were also measured by a dichlorofluorescein diacetate (DCF-DA) assay, which revealed that ROS levels increased in response to B(a)P treatment for 48 h. WB assay also confirmed that each B(a)P treatment of JEG-3 and BeWo cells for 4 h promoted the expression of phosphorylated eukaryotic initiation factor 2 alpha protein (p-eIF2α) and C/EBP homologous protein (CHOP), which are known to be involved in ROS-mediated endoplasmic reticulum stress (ER-stress) related apoptosis. Overall, the protein expression of Bax (a pro-apoptosis marker) increased, while the expression of Bcl-xl (an anti-apoptotic marker) decreased and the number of apoptotic cells increased in response to B(a)P treatment for 48 h. Taken together, these results suggest that B(a)P has the potential to induce apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cells by increasing the ROS level and simultaneously activating ER-stress. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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127. Stem Cell Oriented Exosomes Regulate Cell Proliferation in Hepatoma Carcinoma.
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Karima, Gul, Shin, Kyusoon, Jeong, Jaemin, Choi, Dongho, Hwang, Kyung-Gyun, and Hong, Jong Wook
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STEM cells , *CELL proliferation , *EXOSOMES , *LIVER cells , *HEPATOCELLULAR carcinoma - Abstract
Reprogrammed hepatic stem cells can generate a variety of extracellular vesicular particles including exosomes with similar therapeutic potential. However, their functional application in cancer therapy is restricted due to a poor understanding of their physical properties, anti-proliferative effects, and the underlying mechanism. Here, we explore reprogrammed stem cells that can release vesicular particles with physical properties of exosomes that can exert anti-proliferative effects by regulating cell proliferation-related genes. We obtain vesicular particles with properties of exosomes expressing CD81 and CD63 with the size distribution peak observed at 155 nm. We analyze that as compared to non-treated conditions, vesicular particles have reduced cell proliferation of Hep G2 by 93.6% after 72 h. Furthermore, we also identify that B-cell lymphoma 2 has been reduced by 89.64% and activation of caspase-3 has occurred in treated conditions via the mitochondrial pathway. Therefore, our results may highlight the potential of exosomes from hepatic stem cells to play a vital role in treating liver pathologies. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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128. Eosinophil‐derived interferon‐γ drives transmembrane protein 119–induced new bone formation in chronic rhinosinusitis with nasal polyps.
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Jo, Sungsin, Jin, Bong Joon, Lee, Seung Hoon, Jo, Hye‐Ryeong, Park, Joo Mi, Hwang, Kyung‐Gyun, Rho, Mina, Kim, Tae‐Hwan, and Cho, Seok Hyun
- Subjects
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NASAL polyps , *MEMBRANE proteins , *BONE growth , *BONE cells , *SINUSITIS , *GENE expression , *NASAL mucosa - Abstract
Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory sinonasal disease characterized by eosinophilic infiltration and new bone formation. These changes indicate the severity and prognosis of CRSwNP and may be closely linked to each other. Methods: We performed RNA sequencing to screen specific osteogenic molecules and validated transmembrane protein 119 (TMEM119) expression by quantitative polymerase chain reaction (qPCR) and immunohistochemistry analyses. TMEM119 knockdown was performed to observe the downregulation of bone mineralization. We validated the bone‐forming activity of interferon‐γ (IFN‐γ) and its signaling pathways in cultured primary sinus bone cells. Cellular sources of IFN‐γ were identified using immunohistochemistry and immunofluorescence analyses. Interleukin‐4–eosinophil–IFN‐γ axis and the effect of dupilumab were investigated in Eol‐1 cells. Results: We observed elevated IFN‐γ levels and eosinophils in the nasal fluid and predominantly eosinophil‐derived IFN‐γ in the sinus mucosa of patients with CRSwNP. TMEM119 expression and bone‐forming activities were increased in the osteitic and primary sinus bone cells of CRSwNP. IFN‐γ treatment enhanced bone mineralization and TMEM119 expression via signal transducer and activator of transcription 1 (STAT1) signaling. Moreover, TMEM119 knockdown inhibited sinus bone cell mineralization and dupilumab attenuated IFN‐γ secretion by IL4‐stimulated Eol‐1 cells. Conclusion: Eosinophil‐derived IFN‐γ promotes the bone‐forming activities of sinus bone cells via the STAT1–TMEM119 signaling pathway. Interleukin‐4–eosinophil–IFN‐γ axis may be crucial for TMEM119‐mediated new bone formation in CRSwNP. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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129. Kaempferol, a phytoestrogen, suppressed triclosan-induced epithelial-mesenchymal transition and metastatic-related behaviors of MCF-7 breast cancer cells.
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Lee, Geum-A, Choi, Kyung-Chul, and Hwang, Kyung-A
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PHYTOESTROGENS , *BREAST cancer , *CANCER cell proliferation , *COMEDO carcinoma , *MAMMOGRAMS - Abstract
As a phytoestrogen, kaempferol is known to play a chemopreventive role inhibiting carcinogenesis and cancer progression. In this study, the influences of triclosan, an anti-bacterial agent recently known for an endocrine disrupting chemical (EDC), and kaempferol on breast cancer progression were examined by measuring their effects on epithelial-mesenchymal transition (EMT) and metastatic-related behaviors of MCF-7 breast cancer cells. Morphological changes of MCF-7 cells were observed, and a wound-healing assay was performed after the treatment of triclosan and kaempferol. The effects of triclosan and kaempferol on protein expression of EMT-related markers such as E-cadherin, N-cadherin, Snail, and Slug and metastasis-related markers such as cathepsin B, D, MMP-2 and −9 were investigated by Western blot assay. In microscopic observations, triclosan (10 −6 M) or E2 (10 −9 M) induced transition to mesenchymal phenotype of MCF-7 cells compared with the control. Co–treatment of ICI 182,780 (10 −8 M), an ER antagonist, or kaempferol (25 μM) with E2 or triclosan restored the cellular morphology to an epithelial phenotype. In a wound-healing scratch and a transwell migration assay, triclosan enhanced migration and invasion of MCF-7 cells, but co-treatment of kaempferol or ICI 182,780 reduced the migration and invasion ability of MCF-7 cells to the control level. In addition, kaempferol effectively suppressed E2 or triclosan-induced protein expressions of EMT and metastasis promoting markers. Taken together, triclosan may be a distinct xenoestrogenic EDC to promote EMT, migration, and invasion of MCF-7 breast cancer cells through ER. On the other hand, kaempferol can be an alternative chemopreventive agent to effectively suppress the metastatic behavior of breast cancer induced by an endogenous estrogen as well as exogenous xenoestrogenic compounds including triclosan. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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130. Hydro-isomerization of n-dodecane on Pt–La/Beta catalyst for the production of high quality bio-jet fuel: Effect of La addition.
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Choi, Il-Ho, Lee, Hye-Jin, and Hwang, Kyung-Ran
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FUEL quality , *BRONSTED acids , *CATALYSTS , *ISOMERIZATION , *JET fuel - Abstract
A series of Pt–La/B38 catalysts were prepared for low-temperature isomerization of n- dodecane and the effects of La addition on the textural properties, metal dispersion, acid properties, and catalytic performance were investigated. La co-impregnated with Pt on B38 significantly reduced the Pt size and notably enhanced the uniformity in Pt size. A higher ratio of accessible Pt and medium-strength Brønsted acid sites and a shorter distance between two Pt particles of Pt–La10/B38 resulted in the maximum iso- C 12 yield (59.2–56.2%) in the range of 200–250 °C, due to the reasonable arrangement of active sites caused by La loading. [Display omitted] • Pt–La/HBeta (Si/Al = 38) for low-temperature hydro-isomerization of n-dodecane. • La inhibits agglomeration of Pt and facilitates uniform nano-size Pt dispersion. • Reasonable arrangement of active metal and acid sites caused by La addition. • Pt–La10/HB showed maximum iso-C 12 yield of 59.2–56.2% in a range of 200–250 °C. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
131. In-hospital glycemic variability and all-cause mortality among patients hospitalized for acute heart failure.
- Author
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Chun, Kyeong-Hyeon, Oh, Jaewon, Lee, Chan Joo, Park, Jin Joo, Lee, Sang Eun, Kim, Min-Seok, Cho, Hyun-Jai, Choi, Jin-Oh, Lee, Hae-Young, Hwang, Kyung-Kuk, Kim, Kye Hun, Yoo, Byung-Su, Choi, Dong-Ju, Baek, Sang Hong, Jeon, Eun-Seok, Kim, Jae-Joong, Cho, Myeong-Chan, Chae, Shung Chull, Oh, Byung-Hee, and Kang, Seok-Min
- Subjects
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MORTALITY , *HEART failure , *BLOOD sugar measurement , *HEART failure patients - Abstract
Background: High glycemic variability (GV) is a poor prognostic marker in cardiovascular diseases. We aimed to investigate the association of GV with all-cause mortality in patients with acute heart failure (HF). Methods: The Korean Acute Heart Failure registry enrolled patients hospitalized for acute HF from 2011 to 2014. Blood glucose levels were measured at the time of admission, during hospitalization, and at discharge. We included those who had 3 or more blood glucose measurements in this study. Patients were divided into two groups based on the coefficient of variation (CoV) as an indicator of GV. Among survivors of the index hospitalization, we investigated all-cause mortality at 1 year after discharge. Results: The study analyzed 2,617 patients (median age, 72 years; median left-ventricular ejection fraction, 36%; 53% male). During the median follow-up period of 11 months, 583 patients died. Kaplan–Meier curve analysis revealed that high GV (CoV > 21%) was associated with lower cumulative survival (log-rank P < 0.001). Multivariate Cox proportional analysis showed that high GV was associated with an increased risk of 1-year (HR 1.56, 95% CI 1.26–1.92) mortality. High GV significantly increased the risk of 1-year mortality in non-diabetic patients (HR 1.93, 95% CI 1.47–2.54) but not in diabetic patients (HR 1.19, 95% CI 0.86–1.65, P for interaction = 0.021). Conclusions: High in-hospital GV before discharge was associated with all-cause mortality within 1 year, especially in non-diabetic patients with acute HF. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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132. Heterogeneous ruthenium dye adsorption on nano-structured TiO2 films for dye-sensitized solar cells
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Hwang, Kyung-Jun, Jung, Sung-Hoon, Park, Dong-Won, Yoo, Seung-Joon, and Lee, Jae-Wook
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TITANIUM dioxide , *THIN films , *NANOCRYSTALS , *RUTHENIUM , *ADSORPTION (Chemistry) , *DYE-sensitized solar cells , *ENERGY conversion , *PHOTOELECTRICITY - Abstract
Abstract: TiO2 particles of single-phase anatase nanocrystallites were prepared by the hydrolysis of titanium-tetraisopropoxide under acidic condition and characterized by XRD, FE-SEM, and BET analysis. The adsorption isotherms of dye molecule on TiO2 particles were obtained at three different temperatures (298.15, 313.15, 333.15K) and the experimental data were correlated with Sips isotherm model. Also the isosteric enthalpies of dye adsorption were calculated by the Clausius–Clapeyron equation. The influence of heterogeneous adsorption of cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)-ruthenium(II) bis-tetrabutylammonium dye (N719) on the energy conversion efficiency of solar cell was investigated on the basis of photocurrent–potential curves. The results showed that the conversion efficiency of dye-sensitized solar cell was highly dependent on the heterogeneous adsorption properties of N719 dye on TiO2 films. [Copyright &y& Elsevier]
- Published
- 2010
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133. Increased proliferative activity in endometrium with endometriosis.
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Hwang, Kyung Joo, Park, Dong Wook, Kim, Mi Ran, Kim, Young Ah, Ahn, Seong Hee, and Ryu, Hee Sug
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ENDOMETRIOSIS , *NUCLEAR proteins , *CELL proliferation , *GENE expression , *IMMUNOSTAINING , *IN vitro studies - Published
- 2003
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134. Production of jet-fuel range precursors from carbonyl model compounds in aqueous-phase pyrolysis oil of wood over La-based mixed oxides.
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Lee, Hye-Jin, Choi, Il-Ho, and Hwang, Kyung-Ran
- Subjects
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CARBONYL compounds , *LEWIS pairs (Chemistry) , *OXIDES , *PYROLYSIS , *ACETIC acid , *FURFURAL , *SOLID oxide fuel cells - Abstract
Medium-chain oxygenates as jet-fuel range precursors were produced from carbonyl model compounds in aqueous phase pyrolysis oil via aldol-condensation reaction on La-based mixed oxides. LaCeOx with high medium-strength basic site density related to the tight metal‑oxygen pairs of mixed oxides produced a larger amount of adducts as compared with commercial MgO and LaOx. Water in the reactant appears to have a positive effect on LaCeOx catalyst having tight Lewis acid-base pairs with carbon balance up to 100%. Acetic acid in the solution affected the furfural conversion and the amount of adduct due to competitive adsorptions on active sites. [Display omitted] • Aldol-condensation reaction of aqueous solution of furfural and acetone. • Production of medium-chain oxygenates from small carbonyl compounds on LaCeOx. • Better catalytic activity of LaCeOx due to the tighter Lewis acid-base pairs. • Water dissociative adsorption on acid sites provides active sites for α‑hydrogen extraction. • Acetic acid affected the aldol-condensation due to competitive adsorption on active sites. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
135. A Randomized Controlled Trial of Guided Bone Regeneration for Peri-Implant Dehiscence Defects with Two Anorganic Bovine Bone Materials Covered by Titanium Meshes.
- Author
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Lim, JaeHyung, Jun, Sang Ho, Tallarico, Marco, Park, Jun-Beom, Park, Dae-Ho, Hwang, Kyung-Gyun, and Park, Chang-Joo
- Subjects
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GUIDED bone regeneration , *RANDOMIZED controlled trials , *CONE beam computed tomography , *TITANIUM , *BOS , *BONE density - Abstract
The aim of this study is to compare two low-temperature sintered anorganic bovine bone materials (ABBMs), Bio-Oss (Geistlich, Wolhusen, Switzerland) and A-Oss (Osstem, Seoul, Korea), for GBR in dehiscence defects. A single implant was placed simultaneously with GBR in the buccal or bucco-proximal osseous defect by double-layering of inner allograft and outer ABBM, covered by a preformed ultrafine titanium mesh and an absorbable collagen membrane. Grafted volume changes were evaluated by cone-beam computed tomography, taken preoperatively (T0), immediately after implant surgery (T1), after re-entry surgery (T2), and after delivery of the final restoration (T3). The density of the regenerated bone was assessed by measuring the probing depth on the buccal mid-center of the mesh after removing the mesh at T2. Postoperative sequelae were also recorded. Grafted volume shrinkage of 46.0% (0.78 ± 0.37 cc) and 40.8% (0.79 ± 0.33 cc) in the Bio-Oss group (8 patients) and A-Oss group (8 patients), respectively, was observed at T3 (p < 0.001). There were no significant differences in grafted volume changes according to time periods or bone density between the two groups. Despite postoperative mesh exposure (3 patients), premature removal of these exposed meshes and additional grafting was not necessary, and all implants were functional over the 1-year follow-up period. Both ABBMs with titanium meshes showed no significant difference in the quantity and density of the regenerated bone after GBR for peri-implant defects. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
136. Three components of cigarette smoke altered the growth and apoptosis of metastatic colon cancer cells via inducing the synthesis of reactive oxygen species and endoplasmic reticulum stress.
- Author
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Lee, Hae-Miru, Kim, Cho-Won, Hwang, Kyung-A, Choi, Dal-Woong, and Choi, Kyung-Chul
- Subjects
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PHYSIOLOGICAL effects of tobacco , *COLON cancer risk factors , *APOPTOSIS , *CANCER cells , *REACTIVE oxygen species , *ENDOPLASMIC reticulum - Abstract
Cigarette smoke (CS) is a well-known risk factor for carcinogenesis and has been found to be related to the occurrence and development of colon cancer. In this study, the effect of formaldehyde (FA), benzene (Bz), and isoprene (IP), which are included in main components of CS, on cell viability and apoptosis of SW620 colorectal cancer cells was examined to identify the connection between CS components and colon cancer. In cell viability assay, FA, Bz, and IP decreased cell viability of SW620 cells in a dose dependent manner. In Western blot assay, the protein expression of cell cycle related genes, cyclin D1 & E1, was decreased by FA, Bz, and IP, which corresponded to their inhibitory effect on cell viability. In addition, FA, Bz, and IP increased the protein expression of pro-apoptotic genes, C/EBP homologous protein (CHOP) and Bax, and reduced the protein expression of anti-apoptotic gene, Bcl-2. In reactive oxygen species (ROS) assay using dichlorofluorescin diacetate (DCFH-DA), FA, Bz, and IP increased the ROS production in SW620 cells. In the measurement of apoptotic cells, the numbers of apoptotic cells were increased by the treatment of FA, Bz, and IP. As CHOP is an endoplasmic reticulum (ER)-stress related apoptosis marker of which production is induced by ROS, it was considered that these CS components induce apoptosis of SW620 cells by increasing ROS synthesis and ER-stress. Taken together, these results showed that CS components, i.e., FA, Bz, and IP, inhibited the cell viability of SW620 cells by down-regulating the protein expression of cyclin D1 & E1 and induced apoptosis of SW620 cells by increasing ROS production and simultaneously activating ER-stress. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
137. Some identities of Laguerre polynomials arising from differential equations.
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Kim, Taekyun, Kim, Dae, Hwang, Kyung-Won, and Seo, Jong
- Subjects
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LAGUERRE polynomials , *POLYNOMIALS , *DIFFERENTIAL equations , *IDENTITIES (Mathematics) , *CALCULUS - Abstract
In this paper, we derive a family of ordinary differential equations from the generating function of the Laguerre polynomials. Then these differential equations are used in order to obtain some properties and new identities for those polynomials. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
138. Influence of hexabromocyclododecane and 4-nonylphenol on the regulation of cell growth, apoptosis and migration in prostatic cancer cells.
- Author
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Kim, Seung-Hee, Nam, Ki-Hoan, Hwang, Kyung-A, and Choi, Kyung-Chul
- Subjects
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HEXABROMOCYCLODODECANE , *NONYLPHENOL , *APOPTOSIS , *CANCER cell growth regulation , *CANCER cell migration , *PROSTATE cancer , *CANCER invasiveness - Abstract
The aim of the present study was to determine whether hexabromocyclododecane (HBCD) or 4-nonylphenol (NP) may induce prostatic cancer progression in LNCaP cells. Androgenic effects of HBCD and NP were examined in LNCaP prostate cancer cells expressing androgen receptors (ARs). HBCD and NP increased LNCaP cell viability similar to dihydrotestosterone (DHT) by MTT assay. This phenomenon was reversed by treatment with Casodex, an AR antagonist, suggesting that they act as xenoandrogens via AR signaling pathway. In cell migration assay, HBCD and NP also enhanced LNCaP cell migration similar to DHT. To elucidate underlying mechanisms of their actions on LNCaP, transcriptional levels of cell cycle- and apoptosis-related markers, including cyclin D1, cyclin E, p27, bcl-2, and bax, were determined by reverse transcription (RT)-PCR. An increase in expression cyclin D1 and cyclin E and reduction in p27 and bax mRNA levels were observed by their treatments. Western blot assay showed their alterations in translational levels of cyclin D1, cyclin E, p21, bax, and cathepsin D. Expressions of genes related to a G1/S transition of cell cycle and cathepsin D were elevated, while expression of p21 and bax was decreased. Taken together, these results indicate that HBCD and NP may enhance progression of prostate cancer by modulating growth and migration of LNCaP prostate cells by acting on cell cycle, apoptosis, and metastasis. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
139. FREE node for a single layer free-form envelope subjected to bending moment.
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Oh, Jintak, Ju, Young K., Hwang, Kyung-Ju, Kim, Sang-Dae, and Lho, Seung-Hee
- Subjects
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BENDING moment , *AXIAL loads , *FINITE element method , *STRUCTURAL analysis (Engineering) , *PARAMETERS (Statistics) - Abstract
For free-form structures with a single layer envelope, the node is subjected to axial load, as well as moment. The purpose of this paper is to develop and evaluate a new hollow spherical connector, termed the FREE (Flexible, Resilient, Efficient, Economic) node, for single layer free-form spatial envelopes. Reducing material and efficient shape are important points in the space structure node. Therefore, hollow spherical node sections with different holes were proposed and finite element analysis was performed, to determine the prototype among these parameters. The parameters are the size and shape of the hollow sphere. Bending experiments were also performed, to evaluate the structural capacities of the proposed node; and the corresponding test results were compared with finite element analysis. As a result, it may be said the proposed FREE node satisfied the required capacities. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
140. Brief Report: Autistic Traits Predict Spectral Correlates of Vowel Intelligibility for Female Speakers.
- Author
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Bishop, Jason, Zhou, Chen, Antolovic, Katarina, Grebe, Lauren, Hwang, Kyung Hae, Imaezue, Gerald, Kistanova, Ekaterina, Lee, Kyung Eun, Paulino, Katherine, and Zhang, Sichen
- Subjects
- *
STATISTICS , *VOWELS , *SPEECH perception , *NEUROLOGICAL disorders , *INTELLIGIBILITY of speech , *AUDITORY perception , *SPEECH evaluation , *SEX distribution , *AUTISM , *COMMUNICATION , *DESCRIPTIVE statistics , *DATA analysis , *PHENOTYPES - Abstract
A growing body of research finds that neurotypical autistic traits are predictive of speech perception and language comprehension patterns, but considerably less is known about the influence of these traits on speech production. In this brief report, we present an analysis of vowel productions from 74 American English speakers who participated in a communicative speaking task. Results show higher autistic trait load to be broadly and inversely related to spectral correlates of vowel intelligibility. However, the statistical significance of this relationship is specific to autistic traits along the pragmatic communication dimension, and limited to female speakers. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
141. Pseudopathologic vertebral body enhancement in the presence of superior vena cava obstruction on computed tomography.
- Author
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Kim, Yoon Kyung, Sung, Yon Mi, Hwang, Kyung Hoon, Cho, Eun Kyung, and Choi, Hye-Young
- Subjects
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SUPERIOR vena cava syndrome , *INTERVERTEBRAL disk , *COMPUTED tomography , *PATHOLOGICAL physiology , *COLLATERAL circulation - Abstract
Background context Superior vena cava (SVC) obstruction can cause the development of collateral vessels. During contrast-enhanced thoracic computed tomography (CT), contrast material may reflux into the collaterals such as paravertebral venous plexus. However, an unusual pseudopathologic vertebral body enhancement on CT in the presence of SVC obstruction has not been studied previously. Purpose To demonstrate clinical presentation and imaging findings of pseudopathologic vertebral body enhancement in patients with SVC obstruction. Study design Retrospective study of diagnostic CT images examined at our clinic. Patient sample From March, 2009 to September, 2012, a retrospective radiologic database review was performed to identify patients with obstruction of SVC causing contrast reflux into collateral vessels and presented with an unusual vertebral body enhancement on thoracic CT. Thirteen patients (11 men, mean age 51.4 years) with vertebral body enhancement were enrolled. Outcome measures Enhancement patterns of vertebral bodies were classified as nodular enhancement with round shape occupying less than one-third of vertebral body or polygonal enhancement occupying greater than or equal to one-third of vertebral body on axial image. The locations of enhanced areas within vertebral bodies were described using right lateral/central/left lateral, anterior/posterior, and upper/middle/lower in the x-, y-, or z-axis directions, respectively. Materials and methods Enhancement patterns, locations, and the presence of a connection between vertebral body enhancement and the paravertebral venous plexus were evaluated. Results A total of 39 vertebral body enhancements were found in the 13 patients, involving cervical (n=12), thoracic (n=25), or lumbar (n=2) vertebrae. Vertebral body enhancements showed a nodular (n=19) or a polygonal (n=20) pattern. The central portions of vertebral bodies were more frequently involved. The connection to the paravertebral venous plexus was observed in 34 lesions (87.2%). Conclusions Patients with SVC obstruction with extensive collateral vessels might exhibit a pseudopathologic vertebral enhancement. They tended to involve the central portion of the vertebral body, and most of them showed connection to the paravertebral venous plexus. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
142. Enhancement of the barrier performance in organic/inorganic multilayer thin-film structures by annealing of the parylene layer.
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Kim, Namsu, Graham, Samuel, and Hwang, Kyung-Jun
- Subjects
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SILICON oxide , *ORGANIC compounds , *MULTILAYERED thin films , *ANNEALING of metals , *PARYLENE , *CHEMICAL vapor deposition - Abstract
A multilayered barrier structure was fabricated by chemical vapor deposition of parylene and subsequent plasma-enhanced chemical vapor deposition of SiOx or SiNx. The barrier performance against water vapor ingress was significantly improved by annealing the parylene layer before the deposition of either SiOx or SiNx. The mechanism of this enhancement was investigated using atomic force microscopy, Raman spectroscopy, and X-ray diffraction. The surface roughness of the parylene before the deposition of either SiOx or SiNx was found to correlate closely with the barrier performance of the multilayered structures. In addition, removing absorbed water vapor in the film by annealing results in a lower water vapor transmission rate in the transient region and a longer lag time. Annealing the parylene leads to a large decrease in the effective water vapor transmission rate, which reaches 7.2±3.0×10-6g/m2/day. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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143. Populist Collaborators: The Ilchinhoe and the Japanese Colonization of Korea, 1896–1910.
- Author
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Hwang, Kyung Moon
- Subjects
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NONFICTION ,JAPANESE occupation of Korea, 1910-1945 - Published
- 2016
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144. Prognostic Impact and Predictors of New-Onset Atrial Fibrillation in Heart Failure.
- Author
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Choi, Hyo-In, Lee, Sang Eun, Kim, Min-Seok, Lee, Hae-Young, Cho, Hyun-Jai, Choi, Jin Oh, Jeon, Eun-Seok, Hwang, Kyung-Kuk, Chae, Shung Chull, Baek, Sang Hong, Kang, Seok-Min, Choi, Dong-Ju, Yoo, Byung-Su, Kim, Kye Hun, Cho, Myeong-Chan, Oh, Byung-Hee, and Kim, Jae-Joong
- Subjects
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ATRIAL fibrillation , *HEART failure , *PROPORTIONAL hazards models , *PROGNOSTIC models , *HEART valve diseases , *SURVIVAL analysis (Biometry) , *HEART beat - Abstract
Background: The prognostic impact and predictors of NOAF in HF patients are not fully elucidated. This study aims to determine whether new-onset atrial fibrillation (NOAF) affects patient outcome and investigate predictors of atrial fibrillation (AF) in acute heart failure (HF) patients using real-world data. Methods: The factors associated with NOAF in 2894 patients with sinus rhythm (SR) enrolled in the Korean Acute Heart Failure (KorAHF) registry were investigated. Survival was analyzed using AF as a time-dependent covariate. Relevant predictors of NOAF were analyzed using multivariate proportional hazards models. Results: Over 27.4 months, 187 patients developed AF. The median overall survival time was over 48 and 9.9 months for the SR and NOAF groups, respectively. Cox regression analysis with NOAF as a time-dependent covariate showed a higher risk of death among patients with NOAF. Multivariate Cox modeling showed that age, worsening HF, valvular heart disease (VHD), loop diuretics, lower heart rate, larger left atrium (LA) diameter, and elevated creatinine levels were independently associated with NOAF. Risk score indicated the number of independent predictors. The incidence of NOAF was 2.9%, 9.4%, and 21.8% in the low-risk, moderate-risk, and high-risk groups, respectively (p < 0.001). Conditional inference tree analysis identified worsening HF, heart rate, age, LA diameter, and VHD as discriminators. Conclusions: NOAF was associated with decreased survival in acute HF patients with SR. Age, worsening HF, VHD, loop diuretics, lower heart rate, larger LA diameter, and elevated creatinine could independently predict NOAF. This may be useful to risk-stratify HF patients at risk for AF. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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145. Anticancer effects of the engineered stem cells transduced with therapeutic genes via a selective tumor tropism caused by vascular endothelial growth factor toward HeLa cervical cancer cells.
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Kim, Hye-Sun, Yi, Bo-Rim, Hwang, Kyung-A, Kim, Seung, and Choi, Kyung-Chul
- Abstract
The aim of the present study was to investigate the therapeutic efficacy of genetically engineered stem cells (GESTECs) expressing bacterial cytosine deaminase (CD) and/or human interferon-beta (IFN-β) gene against HeLa cervical cancer and the migration factors of the GESTECs toward the cancer cells. Anticancer effect of GESTECs was examined in a co-culture with HeLa cells using MTT assay to measure cell viability. A transwell migration assay was performed so as to assess the migration capability of the stem cells to cervical cancer cells. Next, several chemoattractant ligands and their receptors related to a selective migration of the stem cells toward HeLa cells were determined by real-time PCR. The cell viability of HeLa cells was decreased in response to 5-fluorocytosine (5-FC), a prodrug, indicating that 5-fluorouracil (5-FU), a toxic metabolite, was converted from 5-FC by CD gene and it caused the cell death in a co-culture system. When IFN-β was additionally expressed with CD gene by these GESTECs, the anticancer activity was significantly increased. In the migration assay, the GESTECs selectively migrated to HeLa cervical cancer cells. As results of real-time PCR, chemoattractant ligands such as MCP-1, SCF, and VEGF were expressed in HeLa cells, and several receptors such as uPAR, VEGFR2, and c-kit were produced by the GESTECs. These GESTECs transduced with CD gene and IFN-β may provide a potential of a novel gene therapy for anticervical cancer treatments via their selective tumor tropism derived from VEGF and VEGFR2 expressions between HeLa cells and the GESTECs. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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146. The property of hydrogen separation from CO2 mixture using Pd-based membranes for carbon capture and storage (CCS).
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Ryi, Shin-Kun, Park, Jong-Soo, Hwang, Kyung-Ran, Lee, Chun-Boo, and Lee, Sung-Wook
- Subjects
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HYDROGEN , *CARBON dioxide , *PALLADIUM , *CARBON sequestration , *COAL , *CHEMICAL reactions , *MEMBRANE separation , *WATER - Abstract
Abstract: This study investigates the module configuration for upscaling CO2 capture capacity to a bench-scale in hydrogen selective Pd-based composite membranes. In order to confirm effective upscaling, four plate-type membranes of two inch diameter were stacked in a newly designed plate-and-frame type module, reaching a total membrane surface area of 6.64 × 10−3 m2 (66.4 cm2). A pure gas test carried out using H2 and He confirmed that there were no effects of module configuration in gas permeation behavior, indicating that the upscale of the separation capacity by numbering-up of membranes using our module design was successful. The CO2 enrichment test was conducted using a 40%CO2 + 60%H2 mixture (i.e. a similar composition for the coal gasifier after both the shift reaction and H2O removal), under high feed pressure and flow rate, i.e. 600–2100 kPa and 0.48–0.72 N m3 h−1. The mixture gas test confirmed that the bench-scale membrane module could enrich 40% of the CO2 at a feed flow rate of 0.48 N m3 h−1 up to 93% with a hydrogen recovery ratio of >90% at 673 K and a total feed pressure of 2100 kPa, i.e. ∼4 times CO2 enrichment capacity of one membrane. [Copyright &y& Elsevier]
- Published
- 2013
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- View/download PDF
147. Production of synthetic natural gas by means of a catalytic nickel membrane
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Ryi, Shin-Kun, Lee, Sung-Wook, Hwang, Kyung-Ran, and Park, Jong-Soo
- Subjects
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SYNTHETIC natural gas , *NICKEL catalysts , *ARTIFICIAL membranes , *GAS producing machines , *METHANATION , *THERMAL stresses , *CHEMICAL reactors , *HEAT treatment - Abstract
Abstract: In this study, a new method of methanation was developed using a catalytic nickel membrane for synthetic natural gas (SNG) production. The methanation reaction is exothermic, so heat that is generated should be removed from the reactor to prevent the methane yield from being reduced and to minimize deactivation of the catalyst due to thermal stress at hot spots. Since the catalytic nickel membrane was made by uniaxial-pressing and thermal treatment of nickel powder, it could readily remove heat from the reactor. Methanation tests conducted at various temperatures, residence times and pressures revealed that the CO and H2 conversions increased with increasing temperature and pressure and reached a maximum value of 99 and 80% at a temperature, residence time and pressure of 350°C, 94ms and 280kPa, respectively. The CH4 increased with increasing pressure and reached 96% at a temperature of 350°C, residence time of 94ms and pressure of 280kPa. The temperature gradient between the top and bottom of the membrane was within 20°C, indicating that heat was reliably transferred and re-distributed throughout the thin (∼2.0mm) metal membrane. From the methanation tests, a new reactor could be designed for high exothermic reactions. [Copyright &y& Elsevier]
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- 2012
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148. Nanocrystalline TiO2 films treated with acid and base catalysts for dye-sensitized solar cells
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Park, Dong-Won, Choi, Yong-Kook, Hwang, Kyung-Jun, Lee, Jae-Wook, Park, Jai Koo, Jang, Hee Dong, Park, Hyung-Sang, and Yoo, Seung-Joon
- Subjects
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NANOCRYSTALS , *TITANIUM dioxide films , *DYE-sensitized solar cells , *ACID-base chemistry , *POROSITY , *PARTICLE size distribution , *ELECTRON transport , *CATALYSIS - Abstract
Abstract: Crystalline size and porosity of TiO2 films are known to be easily controlled by changing acid or base catalyst concentration. This work investigates the influence of acid/base catalyst treatments of TiO2 nanoparticles on the efficiency of dye-sensitized solar cells (DSSCs). The results indicate that the performance of DSSC fabricated with base-treated TiO2 is remarkably better than that fabricated with acid-treated TiO2 because of different film properties including particle size, shape, film porosity, and surface structure and electron transport phenomena. [Copyright &y& Elsevier]
- Published
- 2011
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149. Repair of Pd-based composite membrane by polishing treatment
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Ryi, Shin-Kun, Park, Jong-Soo, Hwang, Kyung-Ran, Lee, Chun-Boo, and Lee, Seong-Wook
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PALLADIUM compounds , *ARTIFICIAL membranes , *SPUTTERING (Physics) , *HYDROGEN , *SCANNING electron microscopy , *HELIUM , *SURFACE coatings , *SEPARATION (Technology) - Abstract
Abstract: In this study, polishing treatment was introduced to repair Pd-based composite membrane. Some pinholes remained after sputtering with palladium followed by heat-treatment at 723 K for 2 h. The pinholes drastically decreased the hydrogen perm-selectivity of the Pd-based composite membrane. In order to remove the pinholes, we introduced polishing treatment after the palladium sputtering. Scanning election microscopy (SEM) analysis and helium leak tests confirmed the effectiveness of the polishing treatment in removing the pinholes. The helium leaks were drastically decreased by the polishing treatment. Hydrogen permeation and helium leak tests showed that the polishing treatment increased the hydrogen perm-selectivity from 52 to >40,000 with a hydrogen permeation flux of 1.8 × 10−1 mol m−2 s−1 at a pressure difference of 100 kPa and temperature of 673 K. The advantage of our membrane fabrication procedures lies in its simplicity. Our coating and polishing method offers the promise of highly reproducible Pd-based composite membrane. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
150. Module configuration in CO2 capture using Pd-based composite membranes
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Ryi, Shin-Kun, Park, Jong-Soo, Hwang, Kyung-Ran, Lee, Chun-Boo, and Lee, Seong-Wook
- Subjects
- *
CARBON dioxide , *PALLADIUM compounds , *ARTIFICIAL membranes , *POROUS materials , *NICKEL , *HYDROGEN , *CHEMICAL reduction , *MIXTURES , *COAL gas - Abstract
Abstract: In this study, the effect of module configuration on the performance of Pd-based membrane devices was examined using a Pd-Au composite membrane deposited on a porous nickel support. Hydrogen permeation flux, recovery, and CO2 enrichment were experimentally examined using two different modules. The module configuration that had a narrower space between the surface of the membrane and cover plate provided a large linear flow velocity of the gas mixture, which allowed for a reduction in the concentration polarization. The CO2 enrichment capacity of the membrane module with a space distance of 0.4 mm was 4 times higher than the module with a space distance of 2.5 mm. In regards to the process design, the membrane with an effective area of 16.6 cm2 could enrich 40% of the CO2 at a flow rate of 2000 ml min−1 up to 87% with a hydrogen recovery ratio of >90% at 673 K and a total feed pressure of 1600 kPa. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
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