54 results on '"Se-Il Park"'
Search Results
2. Distribution characteristics on indoor radon concentration of multiple-use facilities in Gwangju area
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Min-Jin Kim, Se-Il Park, Young-Gwan Cho, Gwang-yeob Seo, Sang-Su An, Jong Min Kim, Min-Cheol Cho, and Seok-jin Bae
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Multiple use ,Distribution (number theory) ,chemistry ,Environmental science ,chemistry.chemical_element ,Radon ,Atmospheric sciences - Published
- 2019
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3. Evaluation of Luminance Distribution by Advertising Lighting Type in Commercial Area of Gwangju
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Min-Cheol Cho, Jeong-Won Jang, Yoonkook Lee, Se-Il Park, Yeonhee Kim, Dae-Haeng Lee, and Young-Gwan Cho
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geography ,geography.geographical_feature_category ,Commercial area ,Light pollution ,Environmental science ,Luminance ,Luminance distribution ,Remote sensing ,Residential area - Published
- 2018
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4. Anti-Inflammatory Effect for Atherosclerosis Progression by Sodium-Glucose Cotransporter 2 (SGLT-2) Inhibitor in a Normoglycemic Rabbit Model
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Oh Hyun Lee, Choongki Kim, Darae Kim, Chul Min Ahn, Donghoon Choi, Yangsoo Jang, Byeong Keuk Kim, Young Guk Ko, Seul Gee Lee, Se-Il Park, Jung Sun Kim, Myeong Ki Hong, Jung Jae Lee, Jaewon Oh, Seung Jun Lee, Yong Ho Lee, Sung Jin Hong, and Ok-Hee Jeon
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medicine.medical_specialty ,Normal diet ,Sodium-glucose transporter-2 ,030204 cardiovascular system & hematology ,Nitric oxide ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Sodium-glucose transporter 2 inhibitors ,Internal Medicine ,medicine ,030212 general & internal medicine ,Dapagliflozin ,Receptor ,business.industry ,Macrophages ,Balloon catheter ,medicine.disease ,Atherosclerosis ,Endocrinology ,Atheroma ,chemistry ,Sodium/Glucose Cotransporter 2 ,Tumor necrosis factor alpha ,Original Article ,Cardiology and Cardiovascular Medicine ,business - Abstract
BACKGROUND AND OBJECTIVES We sought to investigate an anti-atherosclerotic and anti-inflammatory effect of sodium-glucose cotransporter-2 (SGLT-2) inhibitors in normoglycemic atherosclerotic rabbit model. METHODS Male New Zealand white rabbits (n=26) were fed with a 1% high-cholesterol diet for 7 weeks followed by normal diet for 2 weeks. After balloon catheter injury, the rabbits were administered with the Dapagliflozin (1mg/kg/day) or control-medium for 8 weeks (n=13 for each group). All lesions were assessed with angiography, optical coherence tomography (OCT), and histological assessment. RESULTS Atheroma burden (38.51±3.16% vs. 21.91±1.22%, p
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- 2019
5. Preclinical assessment of a modified Occlutech left atrial appendage closure device in a canine model
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Sanghoon Shin, Sung Kyung Bong, Donghoon Choi, Sung Yu Hong, Jai Wun Park, Se-Il Park, Yangsoo Jang, Chi Young Shim, Seul Gee Lee, Geu Ru Hong, and Jung Sun Kim
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medicine.medical_specialty ,Septal Occluder Device ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Pericardial effusion ,Prosthesis Implantation ,03 medical and health sciences ,Dogs ,0302 clinical medicine ,Left atrial ,Internal medicine ,Atrial Fibrillation ,Occlusion ,medicine ,Animals ,Fluoroscopy ,Atrial Appendage ,030212 general & internal medicine ,Embolization ,medicine.diagnostic_test ,business.industry ,Atrial fibrillation ,medicine.disease ,Stroke ,Disease Models, Animal ,Angiography ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Canine model - Abstract
Background LAA occlusion has a similar stroke prevention efficacy compared to anticoagulation treatment for non-valvular atrial fibrillation. Objective The objective of this study was to assess the feasibility and safety of a modified Occlutech® left atrial appendage (LAA) closure device in a canine model. Methods The device was implanted in 10 dogs (33±1kg) using fluoroscopy and transesophageal echocardiography (TEE) guidance. The modified Occlutech® LAA occlusion device was compared with the current version, the Watchman device, and the Amplazter cardiac plug (ACP). LAA occlusion and anchoring to the LAA were evaluated. All dogs were assessed using angiography, TEE, and a gross anatomy examination. Results The 10 LAA occlusion devices were to be implanted into 10 dogs (5 modified Occlutech devices, 3 current version of Occlutech devices, 1 Watchman, and 1 ACP). LAA implantation was not performed in one dog due to transeptal puncture failure. The three current version of Occlutech devices were embolized immediately after implantation, so three modified devices of the same size were implanted securely without embolization. The mean implant size was 20.1±2.0mm. The devices chosen were a mean of 23.3±10.6% larger than the measured landing zone diameters. Post-implant angiography and TEE revealed well-positioned devices without pericardial effusion or impingement on surrounding structures. Conclusions The results of this acute animal study suggested that a modified Occlutech® LAA occlusion device was feasible and had greater anchoring performance in canines. Additional large clinical studies are needed to evaluate safety and efficacy.
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- 2016
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6. Effects of sampling method using moisture condensation tube (MCT) on the detected odor concentration
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Se-Il Park, Eun-Sun Kim, Nan-Hee Kim, Hee-yoon Jeong, Jeong-Won Jang, Youn-Goog Lee, Dong-Soo Kim, and Young-Gwan Cho
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Chromatography ,Materials science ,Odor ,Moisture condensation ,Tube (fluid conveyance) - Published
- 2016
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7. Synergistic protective effects of a statin and an angiotensin receptor blocker for initiation and progression of atherosclerosis
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Se Hoon Kim, Seul Gee Lee, Choongki Kim, Myeong Ki Hong, Jaewon Oh, Donghoon Choi, Byeong Keuk Kim, Jung Sun Kim, Sang Hak Lee, Se-Il Park, Nguyen Viet Phuong Thuy, Sungha Park, Seung Jun Lee, Ok Hee Lee, Young Guk Ko, Jung Jae Lee, Yangsoo Jang, Oh Hyun Lee, Chul Min Ahn, and Sung Jin Hong
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0301 basic medicine ,Male ,Angiotensin receptor ,Physiology ,Positive control ,Tetrazoles ,Angiotensin II Receptor Blockers ,030204 cardiovascular system & hematology ,Pharmacology ,Vascular Medicine ,Biochemistry ,Diagnostic Radiology ,chemistry.chemical_compound ,Mice ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Immune Physiology ,Medicine and Health Sciences ,Rosuvastatin Calcium ,Tomography ,Mammals ,Innate Immune System ,Multidisciplinary ,Pharmaceutics ,Radiology and Imaging ,Imidazoles ,Cell Polarity ,Drugs ,Eukaryota ,Drug Synergism ,Animal Models ,Lipids ,Treatment Outcome ,Cholesterol ,Experimental Organism Systems ,Vertebrates ,Leporids ,Medicine ,Cytokines ,Rabbits ,Cellular Types ,Olmesartan ,medicine.drug ,Research Article ,Statin ,Drug Administration ,medicine.drug_class ,Imaging Techniques ,Science ,Immune Cells ,Immunology ,Research and Analysis Methods ,03 medical and health sciences ,Angiotensin Receptor Antagonists ,Pharmacotherapy ,Drug Therapy ,Diagnostic Medicine ,medicine ,Animals ,Rosuvastatin ,cardiovascular diseases ,Blood Cells ,business.industry ,Macrophages ,Statins ,Organisms ,Biology and Life Sciences ,Cell Biology ,Molecular Development ,Atherosclerosis ,Disease Models, Animal ,030104 developmental biology ,RAW 264.7 Cells ,chemistry ,Immune System ,Amniotes ,Animal Studies ,business ,Developmental Biology - Abstract
AimAlthough the atheroprotective effects of statins and angiotensin II receptor blockers (ARBs) are well-established, little is known about their additive effects, especially during the early period of atherosclerosis. The aim of this study was to investigate whether combination of a statin and an ARB exerts synergistic anti-atherosclerotic effects, and to elucidate the mechanisms of combined effects.MethodsAtherosclerotic plaques were developed in arteries of 23 rabbits using a high-cholesterol diet (HCD) and intra-arterial balloon inflation. Rabbits received one of five different treatment strategies for 4 weeks: positive control [n = 5, HCD]; negative control [n = 3, regular chow diet]; statin [n = 5, HCD and rosuvastatin 10 mg]; ARB [n = 5, HCD and olmesartan 20 mg]; and combination [n = 5, HCD and statin+ARB].ResultsHistological analysis demonstrated that development of atherosclerotic plaques was inhibited more in combination group than in statin group (P = 0.001). Although macrophage infiltration identified by RAM11 staining was not significantly different between combination and individual treatment groups (31.76±4.84% [combination] vs. 38.11±6.53% [statin; P = 0.35] or 35.14±2.87% [ARB; P = 0.62]), the relative proportion of pro-inflammatory M1-macrophages was significantly lower in combination group than in ARB group (3.20±0.47% vs. 5.20±0.78%, P = 0.02). Furthermore, M2-macrophage polarization was higher in combination group than in statin group (17.70±3.04% vs. 7.86±0.68%, P = 0.001).ConclusionCombination treatment with a statin and an ARB produced synergistic protective effects for atherosclerosis initiation and progression, which may be attributed to modulation of macrophage characteristics in the early period of atherosclerosis.
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- 2019
8. Viability assessment after conventional coronary angiography using a novel cardiovascular interventional therapeutic CT system: Comparison with gross morphology in a subacute infarct swine model
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Byunghwan Jeon, Hyuk Jae Chang, Hackjoon Shim, Se-Il Park, Bríain ó Hartaigh, Hoyup Jung, Youngtaek Hong, Namsik Chung, Yangsoo Jang, Seongmin Ha, Iksung Cho, Sanghoon Shin, James K. Min, and Yeonggul Jang
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Coronary angiography ,medicine.medical_specialty ,Swine ,medicine.medical_treatment ,Myocardial Infarction ,Contrast Media ,Anterior Descending Coronary Artery ,Coronary Angiography ,Radiography, Interventional ,Revascularization ,Multimodal Imaging ,Sensitivity and Specificity ,Article ,Hounsfield scale ,Multidetector Computed Tomography ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,Myocardial Stunning ,Tissue Survival ,business.industry ,Delayed hyperenhancement ,Reproducibility of Results ,medicine.disease ,Invasive coronary angiography ,Female ,Gross morphology ,Radiology ,Cardiology and Cardiovascular Medicine ,Nuclear medicine ,business - Abstract
Given the lack of promptness and inevitable use of additional contrast agents, the myocardial viability imaging procedures have not been used widely for determining the need to performing revascularization.This study is aimed to evaluate the feasibility of myocardial viability assessment, consecutively with diagnostic invasive coronary angiography (ICA) without use of additional contrast agent, using a novel hybrid system comprising ICA and multislice CT (MSCT).In all, 14 Yucatan miniature swine models (female; age, 3 months; weight, 28-30 kg) were subjected to ICA followed by balloon occlusion (90 minutes) and reperfusion of the left anterior descending coronary artery. Two weeks after induction of myocardial infarction, delayed hyperenhancement (DHE) images were obtained, using a novel combined machine comprising ICA and 320-channel MSCT scanner (Aquilion ONE, Toshiba), after 2, 5, 7, 10, 15, and 20 minutes after conventional ICA. The heart was sliced in 10-mm consecutive sections in the short-axis plane and was embedded in a solution of 1% triphenyltetrazolium chloride (TTC). Infarct size was determined as TTC-negative areas as a percentage of total left ventricular area. On MSCT images, infarct size per slice was calculated by dividing the DHE area by the total slice area (%) and compared with histochemical analyses.Serial MSCT scans revealed a peak CT attenuation of the infarct area (222.5 ± 36.5 Hounsfield units) with a maximum mean difference in CT attenuation between the infarct areas and normal myocardium of at 2 minutes after contrast injection (106.4; P for difference = 0.002). Furthermore, the percentage difference of infarct size by MSCT vs histopathologic specimen was significantly lower at 2 (8.5% ± 1.8%) and 5 minutes (9.5% ± 1.9%) than those after 7 minutes. Direct comparisons of slice-matched DHE area by MSCT demonstrated excellent correlation with TTC-derived infarct size (r = 0.952; P.001). Bland-Altman plots of the differences between DHE by MSCT and TTC-derived infarct measurements plotted against their means showed good agreement between the 2 methods.The feasibility of myocardial viability assessment by DHE using MSCT after conventional ICA was proven in experimental models, and the optimal viability images were obtained after 2 to 5 minutes after the final intracoronary injection of contrast agent for conventional ICA.
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- 2015
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9. Feasibility of Selective Catheter-Directed Coronary Computed Tomography Angiography Using Ultralow-Dose Intracoronary Contrast Injection in a Swine Model
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Ji Min Sung, Byunghwan Jeon, Sunghee Jung, Seongmin Ha, Hyung Bok Park, Hackjoon Shim, Bríain O. Hartaigh, Sanghoon Shin, Youngtaek Hong, Yeonggul Jang, Se-Il Park, Reza Arsanjani, Byoung Kwon Lee, and Hyuk Jae Chang
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Cardiac Catheterization ,medicine.medical_specialty ,medicine.medical_treatment ,Contrast Media ,Wine ,Coronary Angiography ,Sensitivity and Specificity ,Iopamidol ,Coronary artery disease ,Radiation Protection ,Hounsfield scale ,medicine.artery ,Image Interpretation, Computer-Assisted ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Saline ,Dose-Response Relationship, Drug ,business.industry ,Reproducibility of Results ,General Medicine ,Image Enhancement ,medicine.disease ,Catheter ,Contrast medium ,Right coronary artery ,Feasibility Studies ,Female ,Radiology ,Tomography ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,medicine.drug - Abstract
Objective Selective catheter-directed intracoronary contrast injected coronary computed tomography angiography (selective CCTA) has recently been introduced for on-site evaluation of coronary artery disease during coronary artery catheterization. In this study, we aimed to develop a feasible protocol for selective CCTA using ultralow-dose contrast medium as compared with conventional intravenous CCTA (IV CCTA). Materials and methods A novel combined system incorporating coronary angiography and a 320-detector row computed tomographic scanner was used to study 4 swine (35-40 kg) under animal institutional review board approval. A selective CCTA scan was simultaneously performed with an injection of 13.13 mgI/mL of modulated contrast medium at multiple different injection rates including 2, 3, and 4 mL/s and different total injection volumes of either 20 or 30 mL. Intravenous CCTA was performed with 60 mL of contrast medium, followed by 30 mL of saline chaser at 5 mL/s. Coronary mean and peak intensity, transluminal attenuation gradient, as well as 3-dimensional maximum intensity projections were obtained. Results Attenuation values (mean ± standard error, in Hounsfield units [HUs]) of selective CCTA for the left anterior descending (LAD) and right coronary artery (RCA) using the various combinations of injection rates and total injection volumes were as follows: 20 mL at 2 mL/s (LAD, 270.3 ± 20.4 HU; RCA, 322.6 ± 7.4 HU), 20 mL at 3 mL/s (LAD, 262.9 ± 20.4 HU; RCA, 264.7 ± 7.4 HU), 30 mL at 3 mL/s (LAD, 276.8 ± 20.4 HU; RCA, 274.0 ± 7.4 HU), 20 mL at 4 mL/s (LAD, 268.0 ± 20.4 HU; RCA, 277.7 ± 7.4 HU), and 30 mL at 4 mL/s (LAD, 251.3 ± 20.4 HU; RCA, 334.7 ± 7.4 HU). The representative protocol of the selective CCTA studies produced results within the optimal enhancement range (approximately 250-350 HU) for all segments, and comparison of transluminal attenuation gradient data with selective CCTA and IV CCTA studies demonstrated that the former method was more homogenous (-1.5245 and -1.7558 for LAD as well as 0.0459 and 0.0799 for RCA, respectively). Notably, the volume of iodine contrast medium used for selective CCTA was reported to be 1.09% (0.2 g) of IV CCTA (24 g). Conclusions The current findings demonstrate the feasibility of selective CCTA using ultralow-dose intracoronary contrast injection. This technique may provide additional means of coronary evaluation in patients who may require strategic planning before a procedure using a combined modality system.
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- 2015
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10. Air Environmental Characteristics of a Greenway Park in Gwangju
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Kyoung-Woo Min, Se-Il Park, Do-Sool Kim, Kyoung-Soek Lee, Ok-hyun Park, Won-Sam Jeung, Young-Gwan Cho, Dae-Hang Lee, and Kwan-Ju Yoon
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Hydrology ,Air pollutants ,Urban forest ,Air temperature ,Environmental engineering ,Environmental science ,Health related ,Noise level ,Particulates ,Air quality index - Abstract
Objectives: This study aimed to survey the characteristics of air quality and meteorological conditions in a greenway park. Methods: We measured meteorological and health related factors, including noise, particulate matter () and selected gaseous air pollutants at three locations in a greenway park and on a general roadside as comparison. The measurements were repeated four times from April to October 2014. Results: The average air temperature in the greenway park was which was lower than on the general roadside. The average concentration in the greenway park was , a level 2-3 times lower than that at the roadside. The noise level at the greenway site was 4.4 dB(A)- 23.0 dB(A) lower than at the roadside. The average CO, , and NOx concentrations in the greenway park were lower than at the roadside. The average phytoncide and anions concentrations in the greenway park were higher than at the roadside. Conclusions: The urban forest of the greenway park may have some impact on air quality and meteorological conditions.
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- 2015
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11. Generation of Equine-Induced Pluripotent Stem Cells and Analysis of Their Therapeutic Potential for Muscle Injuries
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Eun-Joo Lee, Eun-Mi Lee, Ssang-Goo Cho, Ah Young Kim, Se-Il Park, Jin-Kyu Park, Hong Kyun Kim, Kyu-Shik Jeong, and Shin-Yoon Kim
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0301 basic medicine ,Male ,Pathology ,medicine.medical_specialty ,Cellular differentiation ,Induced Pluripotent Stem Cells ,Biomedical Engineering ,lcsh:Medicine ,Gene Expression ,Mice, Transgenic ,Embryoid body ,Biology ,Muscular Dystrophies ,03 medical and health sciences ,Kruppel-Like Factor 4 ,Mice ,SOX2 ,medicine ,Animals ,Regeneration ,Horses ,Induced pluripotent stem cell ,Muscle, Skeletal ,Cells, Cultured ,Embryoid Bodies ,Elapid Venoms ,Transplantation ,Regeneration (biology) ,Stem Cells ,lcsh:R ,PAX7 Transcription Factor ,Cell Differentiation ,Cell Biology ,Cellular Reprogramming ,Cell biology ,Mice, Inbred C57BL ,030104 developmental biology ,Adipose Tissue ,Mice, Inbred mdx ,Myogenin ,Stem cell ,Reprogramming ,Transcription Factors - Abstract
Horse health has become a major concern with the expansion of horse-related industries and sports; the importance of healthy muscles for horse performance and daily activities is undisputed. Here we generated equine-induced pluripotent stem cells (E-iPSCs) by reprogramming equine adipose-derived stem cells (E-ADSCs) into iPSCs using a polycistronic lentiviral vector encoding four transcription factors (i.e., Oct4, Sox2, Klf4, and c-Myc) and then examined their pluripotent characteristics. Subsequently, established E-iPSCs were transplanted into muscle-injured Rag/ mdx mice. The histopathology results showed that E-iPSC-transplanted mice exhibited enhanced muscle regeneration compared to controls. In addition, E-iPSC-derived myofibers were observed in the injured muscles. In conclusion, we show that E-iPSCs could be successfully generated from equine ADSCs and transplanted into injured muscles and that E-iPSCs have the capacity to induce regeneration of injured muscles.
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- 2016
12. Study on Security Transmission of Personal Patient Information in Aerial Emergency Medical Environments
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Se-Il Park, Yong-Hee Lee, Ho-Young Jeong, Soon-Seok Kim, and Dong-Ho Kim
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Scheme (programming language) ,Process (engineering) ,business.industry ,International standard ,Gateway (computer program) ,Computer security ,computer.software_genre ,Transmission (telecommunications) ,Patient information ,Medicine ,Basic service ,business ,Secure transmission ,computer ,computer.programming_language - Abstract
The basic service model is to be process transmting patient health information from various medical devices to evacuation hospital through gateway collecting it in aerial emergency medicine environments. In this paper, we study on the most secure transmission scheme in case that personal patient informations are transmitted from medical devices to gateway. Moreover we compare and analyze existing methods on secure transmission and suggest an optimal alternative on the basis of international standard, ISO/IEEE 11073.
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- 2012
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13. Time-sequential modulation in expression of growth factors from platelet-rich plasma (PRP) on the chondrocyte cultures
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Sun Hee Do, Myun-Whan Ahn, Se-Il Park, Sukyoung Kim, and Hye-Rim Lee
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Male ,Transcription, Genetic ,medicine.medical_treatment ,Clinical Biochemistry ,Chondrocyte ,chemistry.chemical_compound ,Chondrocytes ,medicine ,Animals ,Platelet ,Cell Shape ,Collagen Type II ,Molecular Biology ,Cells, Cultured ,Aggrecan ,Cell Proliferation ,Platelet-Rich Plasma ,Growth factor ,Cartilage ,Cell Biology ,General Medicine ,Culture Media ,Cell biology ,Vascular endothelial growth factor ,medicine.anatomical_structure ,Gene Expression Regulation ,chemistry ,Platelet-rich plasma ,Immunology ,Intercellular Signaling Peptides and Proteins ,Rabbits ,Wound healing - Abstract
Platelets are involved in hemostasis, wound healing, and tumor growth. Autologous blood products are commonly used to facilitate healing in a variety of clinical surgery applications. Recently, it was shown that platelet-rich plasma (PRP) has more specific growth factors that participate in the healing process. This study investigated the expression of PRP growth factors and evaluated their potential role in the cartilage regeneration using primary isolated chondrocytes. PRP obtained from New Zealand White rabbit by low speed centrifugation. Extracted PRPs contained 6-10 × 10(6) platelet/μl and concentration of platelets was slightly variable. Primary isolated chondrocytes from the same rabbits were cultured and treated with 0.1-20% PRP. The cells were collected and examined by reverse transcription-polymerase chain reaction and cytochemical staining. The expression of sex determining region Y-box 9, transforming growth factor-beta, vascular endothelial growth factor, and chondromdulin-I was increased in chondrocyte cultures with 10% PRP by time-dependent manner. To maintain the integrity of the cartilage, the proteoglycan contents were also up-regulated from the mRNA of aggrecan and positive Safranin-O staining in PRP concentration- and time-dependent manner. PRP provides crucial growth factors related to chondrocyte proliferation and differentiation through time-sequential modulation. Controlled in vivo trials for cartilage regeneration are needed.
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- 2011
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14. Systemic transplantation of human adipose-derived stem cells stimulates bone repair by promoting osteoblast and osteoclast function
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Kyung Hee Lee, Jin-Man Kim, Hong In Shin, Yong Jin Kim, Chang Yong Ko, Joseph Kwon, Keuk Jun Kim, Se-Il Park, Jae Ho Jeong, Jae Ryong Kim, Dong Won Bae, Hyun Sook Lim, Hansung Kim, Daewon Jeong, Young mi Moon, and Hyun-Soo Kim
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medicine.medical_specialty ,Bone Regeneration ,MAP Kinase Kinase 4 ,Gene Expression ,Osteoclasts ,Bone healing ,Biology ,Bone tissue ,Mice ,Paracrine signalling ,Osteoclast ,Internal medicine ,Adipocytes ,medicine ,Animals ,Humans ,Extracellular Signal-Regulated MAP Kinases ,systemic transplantation ,Bone regeneration ,Cells, Cultured ,Cell Proliferation ,adipose-derived stem cell ,Osteoblasts ,Stem Cells ,Cell Differentiation ,Osteoblast ,Articles ,Cell Biology ,osteoporosis ,Transplantation ,medicine.anatomical_structure ,Endocrinology ,Culture Media, Conditioned ,osteoclast ,osteoblast ,Cancer research ,Molecular Medicine ,Stem cell ,Signal Transduction ,Stem Cell Transplantation - Abstract
Systemic transplantation of adipose-derived stem cells (ASCs) is emerging as a novel therapeutic option for functional recovery of diverse damaged tissues. This study investigated the effects of systemic transplantation of human ASCs (hASCs) on bone repair. We found that hASCs secrete various bone cell-activating factors, including hepatocyte growth factor and extracellular matrix proteins. Systemic transplantation of hASCs into ovariectomized mice induced an increased number of both osteoblasts and osteoclasts in bone tissue and thereby prevented bone loss. We also observed that conditioned medium from hASCs is capable of stimulating proliferation and differentiation of osteoblasts via Smad/extracellular signal-regulated kinase (ERK)/JNK (c-jun NH(2) -terminal kinase) activation as well as survival and differentiation of osteoclasts via ERK/JNK/p38 activation in vitro. Overall, our findings suggest that paracrine factors secreted from hASCs improve bone repair and that hASCs can be a valuable tool for use in osteoporosis therapy.
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- 2011
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15. Morphological abnormalities, impaired fetal development and decrease in myostatin expression following somatic cell nuclear transfer in dogs
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Woo-Suk Hwang, Mi-Ran Ki, Ji-Hyun Lee, Eun-Mi Lee, Il-Hwa Hong, Ah Young Kim, Taeyoung Shin, Yeonwoo Jeong, Se-Il Park, Sang-Hwan Hyun, Sang-Young You, Jin-Kyu Park, Seon-Young Han, and Kyu-Shik Jeong
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Fetus ,medicine.medical_specialty ,biology ,Somatic cell ,Offspring ,Embryogenesis ,Cell Biology ,Myostatin ,Muscle hypertrophy ,Endocrinology ,Internal medicine ,Genetics ,medicine ,biology.protein ,Macroglossia ,Somatic cell nuclear transfer ,medicine.symptom ,Developmental Biology - Abstract
Several mammals, including dogs, have been successfully cloned using somatic cell nuclear transfer (SCNT), but the efficiency of generating normal, live offspring is relatively low. Although the high failure rate has been attributed to incomplete reprogramming of the somatic nuclei during the cloning process, the exact cause is not fully known. To elucidate the cause of death in cloned offspring, 12 deceased offspring cloned by SCNT were necropsied. The clones were either stillborn just prior to delivery or died with dyspnea shortly after birth. On gross examination, defects in the anterior abdominal wall and increased heart and liver sizes were found. Notably, a significant increase in muscle mass and macroglossia lesions were observed in deceased SCNT-cloned dogs. Interestingly, the expression of myostatin, a negative regulator of muscle growth during embryogenesis, was down-regulated at the mRNA level in tongues and skeletal muscles of SCNT-cloned dogs compared with a normal dog. Results of the present study suggest that decreased expression of myostatin in SCNT-cloned dogs may be involved in morphological abnormalities such as increased muscle mass and macroglossia, which may contribute to impaired fetal development and poor survival rates.
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- 2011
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16. Fetal death of dogs after the ingestion of a soil conditioner
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Se-Il Park, Seung-Keun Lee, Jin-Kyu Park, Mi-Ran Ki, Kyu-Shik Jeong, Tae-Eog Kwon, and Il-Hwa Hong
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Diarrhea ,endocrine system ,medicine.medical_specialty ,Veterinary medicine ,Vomiting ,Ricin ,Toxicology ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Dogs ,Republic of Korea ,medicine ,Animals ,Ingestion ,Dog Diseases ,biology ,business.industry ,Stomach ,Ricinus ,food and beverages ,Cell Biology ,General Medicine ,biology.organism_classification ,Surgery ,carbohydrates (lipids) ,Soil conditioner ,enzymes and coenzymes (carbohydrates) ,medicine.anatomical_structure ,chemistry ,Castor oil ,Toxicity ,medicine.symptom ,Agrochemicals ,Gastrointestinal Hemorrhage ,business ,medicine.drug - Abstract
Castor beans (Ricinus communis) contain ricin, which is one of the most toxic substances of plant origin. Ricin toxicosis has been reported in different countries with usually ingestion of castor beans or plants in both animals and humans. However, ricin toxicosis by ingestion of some products containing castor oil cake has rarely been reported. This paper describes outbreaks of dog death by ricin toxicosis after accidental ingestion of the same soil conditioner. Fifteen dogs showed toxic symptoms such as severe vomiting, abdominal pain and hemorrhagic diarrhea, and then thirteen dogs died in a few days. The soil conditioner dogs ingested consisted of 10% castor oil cake containing ricin. On the basis of clinical signs, laboratory and pathologic findings, a diagnosis of ricin toxicosis was established in the present case. In comparison with previous cases by ingestion of castor beans, the dogs' morbidity was very high in the present case. The ingestion of castor oil cake may be more dangerous to life than the castor beans. It is because mortality by ingestion of castor beans depends on the degree of mastication of the beans, whereas ricin in oil cake is easily absorbed from the stomach and the intestines. As ricin is a heat-labile toxin, products containing ricin or oil cake should be properly treated with heat and have written caution sentences about toxicosis, and be kept out of reach of domestic animals and children.
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- 2011
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17. Facile Preparation of a Hybrid Nanoprobe for Triple-Modality Optical/PET/MR Imaging
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Gwang Il An, Mi Kyung Yu, Hong Joo Kim, Yongmin Chang, Kyu-Shik Jeong, Sangyong Jon, Il-Hwa Hong, Michael J. Welch, Yeong Su Ha, Jeongsoo Yoo, Jungmin Oh, Eun Kyung Wang, Jeong Chan Park, Joo-Hyun Kim, Se-Il Park, and Tae Hyun Choi
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medicine.medical_specialty ,Materials science ,Modality (human–computer interaction) ,medicine.diagnostic_test ,Optical Devices ,Nanoprobe ,General Chemistry ,Magnetic Resonance Imaging ,Biomaterials ,Positron emission tomography ,Positron-Emission Tomography ,medicine ,Nanotechnology ,General Materials Science ,Medical physics ,Pet mr imaging ,Algorithms ,Biotechnology ,Biomedical engineering - Published
- 2010
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18. Fabrication of Carbon Microneedle Arrays with High Aspect Ratios and The Control of Hydrophobicity of These Arrays for Bio-Applications
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Kwang-Cheol Lee, Se Il Park, Seung-Seob Lee, Seok-Woo Lee, and Jung A Lee
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Microelectromechanical systems ,Materials science ,Fabrication ,chemistry ,Mechanical Engineering ,chemistry.chemical_element ,Nanotechnology ,Carbon - Abstract
A. Winkleman 등은 건식 식각(Reactive ion etching)을 이용해 나노 팁을 가지는 실리콘 어레이를 제조한 후† Corresponding Author 표면처리(Silanization)를 하였고, B. Cortese 등은 PDMS Key Words : Carbon Nanotip(탄소 나노팁), HAR Carbon Microneedle(고종횡비 탄소 마이크로니들), MEMS(멤스), Hydrophobicity Control(소수성 제어) 초록: 본 논문에서는 뒷면 노광법과 감광제의 열분해법을 이용하여 다양한 형상을 가지는 탄소 마이크로니들의 제조방법과 제조된 마이크로니들을 사용하여 소수성 표면제어에 대한 연구를 수행하였다. SU-8이 도포된 표면마스크 뒷면으로부터 자외선을 조사하여 다양한 지름, 간격, 그리고 높이를 가지는 폴리머 마이크로니들을 제조하였다. 이 니들은 이후 열처리공정을 통해서 수축, 열변형 등의 형상변화를 거치면서 10이상의 높은 종횡비와 나노사이즈의 뾰족한 팁을 가지는 탄소 재질의 마이크로니들로 변하게 된다. 탄소 마이크로니들을 가지는 석영기판은 친수성 표면을 가지고 있기 때문에 표면에너지가 낮은 물질을 처리하여 소수성 정도를 제어하였다. HMDS처리는 SU-8 니들보다는 탄소 니들의 경우에 표면의 소수성 조절에 효과가 있음을 접촉각의 측정과 XPS 측정결과로부터 확인할 수 있었다. 본 논문에서 제시하는 탄소 마이크로니들의 제조기술과 표면처리기술은 세포분석 및 바이오분야 그리고 자기세정분야 등에서 유용하게 사용될 수 있다. Abstract: This paper reports the fabrication of geometry-controlled carbon microneedles by a backside exposure method and pyrolysis. The SU-8 microneedles are a polymer precursor in a carbonization process, which geometries such as base diameter, spacing, and aspect ratio can be controlled in a photolithography step. Using this fabrication method, highly reproducible carbon microneedles, which have high aspect ratios of more than 10 and very sharp nanotips, can be realized. The quartz surface with carbon microneedles becomes very hydrophilic and its wettability is adjusted by carrying out the silane treatment. In the carbon microneedle array (3 μm × 3 μm), the contact angle is extremly enhanced (~180°); this will be advantageous in developing low-drag microfluidics and labs-on-a-chip as well as in other bio-applications.
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- 2010
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19. Sudden Death Caused by Clostridium perfringens Type D Enterotoxemia in Feedlot Cattle
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Kyu-Shik Jeong, Dongmi Kwak, Se-Il Park, Seong-Jun Jang, Tae-Hwan Kim, Jin-Kyu Park, Yu-Jeong Cho, Sun Hee Do, Sang-Joon Park, Mi-Ran Ki, Il-Hwa Hong, and Ae Ri Ji
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Pathology ,medicine.medical_specialty ,Spleen ,Ileum ,Biology ,Clostridium perfringens ,medicine.disease ,medicine.disease_cause ,Sudden death ,Enterotoxemia ,Enteritis ,medicine.anatomical_structure ,Lymphatic system ,medicine ,Colostrum - Abstract
Sudden deaths have occurred in feedlot cattle with marked necro-hemorrhagic enteritis of the jejunum, ileum and colon. Suckling beef calves are the most frequently affected. Over-consumption of large amounts of milk, inadequate colostrum intake, chilling and stress are conducive to the development of enterotoxemia. Enterotoxemia caused by Clostridium perfringens type D mostly occurs following a sudden change of diet, particularly to feeds made richer in order to grow the cattle to market weight in feedlots. During July 2006, sudden deaths of cattle occurred in the Youngcheon regional area of Gyeongbuk province. There were no significant clinical signs except anorexia, depression, intermittent diarrhea and mild respiratory failure. Histological findings revealed a prominent intranuclear inclusion as well as infiltration of the globular leukocytes in various organs including the heart, kidneys, liver, spleen and lymph nodes. Spleen and lymphatic tissues showed lymphatic necrosis and a starry sky appearance. In the submucosa of the small intestines, basophilic aggregation was detected with massive infiltration of the globular leukocytes and eosinophils. Gram staining for the tissue sections containing inclusions of the small intestines revealed a positive histochemical reaction. Taken together, we suggest that Clostridium perfringens type D-induced enterotoxemia is determined to be the cause of sudden death of feedlot cattle.
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- 2010
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20. Macrophage polarization and acceleration of atherosclerotic plaques in a swine model
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Seul Gee Lee, Se Hoon Kim, Sungha Park, Jaewon Oh, Jung Sun Kim, Se-Il Park, Sung Kyung Bong, Sang Hak Lee, and Yangsoo Jang
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0301 basic medicine ,Pathology ,Swine ,lcsh:Medicine ,Apoptosis ,030204 cardiovascular system & hematology ,Pathology and Laboratory Medicine ,Vascular Medicine ,Diagnostic Radiology ,White Blood Cells ,0302 clinical medicine ,Animal Cells ,Medicine and Health Sciences ,HMGB1 Protein ,lcsh:Science ,Immune Response ,Tomography ,Coronary Arteries ,Multidisciplinary ,Cell Death ,biology ,medicine.diagnostic_test ,CD68 ,Radiology and Imaging ,Arteries ,Tunica intima ,Plaque, Atherosclerotic ,Pathophysiology ,medicine.anatomical_structure ,Cell Processes ,Swine, Miniature ,Tumor necrosis factor alpha ,Cellular Types ,Anatomy ,Research Article ,medicine.medical_specialty ,Imaging Techniques ,Immune Cells ,Inflammatory Diseases ,Immunology ,Macrophage polarization ,Research and Analysis Methods ,HMGB1 ,03 medical and health sciences ,Signs and Symptoms ,Diagnostic Medicine ,medicine ,Animals ,Immunohistochemistry Techniques ,Inflammation ,Blood Cells ,Tumor Necrosis Factor-alpha ,business.industry ,Macrophages ,lcsh:R ,Balloon catheter ,Biology and Life Sciences ,Cell Biology ,Atherosclerosis ,Histochemistry and Cytochemistry Techniques ,Disease Models, Animal ,030104 developmental biology ,Angiography ,Cardiovascular Anatomy ,Immunologic Techniques ,biology.protein ,Blood Vessels ,lcsh:Q ,Tunica Intima ,business - Abstract
Aims Atherosclerosis is a well-known cause of cardiovascular disease and is associated with a variety of inflammatory reactions. However, an adequate large-animal model of advanced plaques to investigate the pathophysiology of atherosclerosis is lacking. Therefore, we developed and assessed a swine model of advanced atherosclerotic plaques with macrophage polarization. Methods Mini-pigs were fed a 2% high-cholesterol diet for 7 weeks followed by withdrawal periods of 4 weeks. Endothelial denudation was performed using a balloon catheter on 32 coronary and femoral arteries of 8 mini-pigs. Inflammatory proteins (high-mobility group box 1 [HMGB1] or tumor necrosis factor alpha (TNF-α) were injected via a micro-infusion catheter into the vessel wall. All lesions were assessed with angiography and optical coherence tomography and all tissues were harvested for histological evaluation. Results Intima/plaque area was significantly higher in the HMGB1- and TNF-α-injected groups compared to the saline-injected group (p = 0.002). CD68 antibody detection and polarization of M1 macrophages significantly increased in the inflammatory protein-injected groups (p
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- 2018
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21. Vitamin C deficiency attenuates liver fibrosis by way of up-regulated peroxisome proliferator-activated receptor-gamma expression in senescence marker protein 30 knockout mice
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Se-Il Park, Ae-Ri Ji, Kyu-Shik Jeong, Sung-Eun Yoo, Hae Young Chung, Il-Hwa Hong, Hye-Rim Lee, Jin-Kyu Park, Akihito Ishigami, Mi-Ran Ki, and Ji Min Kim
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Liver Cirrhosis ,Male ,Vitamin ,medicine.medical_specialty ,Peroxisome proliferator-activated receptor ,Smad Proteins ,Ascorbic Acid ,Mice ,chemistry.chemical_compound ,Internal medicine ,Hepatic Stellate Cells ,medicine ,Animals ,Mice, Knockout ,chemistry.chemical_classification ,Hepatology ,biology ,Carbon Tetrachloride Poisoning ,Calcium-Binding Proteins ,Intracellular Signaling Peptides and Proteins ,Transforming growth factor beta ,Ascorbic acid ,PPAR gamma ,Endocrinology ,chemistry ,Apoptosis ,Knockout mouse ,Hepatic stellate cell ,biology.protein ,Hepatic fibrosis - Abstract
Senescence marker protein 30 (SMP30), an important aging marker molecule that is highly expressed in the liver, has been known to protect hepatocytes from apoptosis by the synthesis of vitamin C. To explore the function of SMP30 in liver fibrosis, the effect of SMP30 deficiency on liver fibrosis was investigated in SMP30 knockout (KO) mice. Moreover, the in vivo results were further confirmed by way of hepatic stellate cell (HSC) isolation. We demonstrated that carbon tetrachloride (CCl4)-induced liver fibrosis and the nuclear translocation of p-Smad2/3, the immediate downstream of transforming growth factor beta (TGF-β), were significantly inhibited in the liver of SMP30 KO mice compared with wildtype (WT) mice. We also confirmed that both WT and SMP30 KO HSCs did not express SMP30. Finally, we further confirmed that up-regulation of peroxisome proliferator-activated receptor-gamma (PPAR-γ) caused by a lack of vitamin C was the pivotal factor in the mechanisms for attenuated liver fibrosis of SMP30 KO mice, and feeding with vitamin C restored CCl4-induced liver fibrosis in SMP30 KO mice. Conclusion: Vitamin C deficiency by SMP30 depletion attenuated liver fibrosis by way of up-regulated PPAR-γ expression in SMP30 KO mice. Our results provide, for the first time, the possible mechanisms underlying inhibition of HSC activation associated with vitamin C and PPAR-γ up-regulation in liver fibrosis of SMP30 KO mice. (HEPATOLOGY 2010.)
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- 2009
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22. Sputter Deposition of ${\rm MoSi}_{2}$ Film as a Barrier for Nb-Based Josephson Junction
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Yonuk Chong, Se Il Park, and Kyu Tae Kim
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Josephson effect ,Materials science ,business.industry ,Niobium ,chemistry.chemical_element ,Sputter deposition ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,chemistry ,Sputtering ,Silicide ,Deposition (phase transition) ,Optoelectronics ,Electrical and Electronic Engineering ,Thin film ,business ,Sheet resistance - Abstract
Recently, sputter-deposited MoSi2 films have been successfully used as a barrier material in Nb/MoSi2/Nb Josephson junctions. In this report, we present our study on the deposition conditions of MoSi2 film for electronics application. We investigated the film stress and sheet resistance as a function of deposition conditions. We also studied the micro-structural change in the film according to the deposition conditions using electron microscopes. We suggest that the thermal strain need to be considered in order to get a reliable junction.
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- 2009
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23. An electrochemical impedance biosensor with aptamer-modified pyrolyzed carbon electrode for label-free protein detection
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Kwang-Cheol Lee, Seongpil Hwang, Juhyoun Kwak, Seung S. Lee, Se Il Park, and Jung A Lee
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Working electrode ,Materials science ,technology, industry, and agriculture ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,Photoresist ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Dielectric spectroscopy ,Carbon film ,Chemical engineering ,chemistry ,Electrode ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation ,Biosensor ,Carbon ,Pyrolysis - Abstract
We present an electrochemical impedance biosensor utilizing pyrolyzed carbon film as a working electrode material for aptamer-based thrombin detection. Batch-fabricated, smooth thin film carbon electrodes, which are fabricated by photolithography and photoresist thermal decomposition at high temperatures in inert ambient, are obtained for integrated electrochemical biosensors. To confirm the suitability of pyrolyzed carbon for use in an electrochemical biosensor, physical and electrical properties of carbon film pyrolyzed with a positive photoresist, AZ9260, were studied. Film thickness after pyrolysis was between 19% and 15% relative to the initial photoresist thickness and the cross-section was changed from rectangular to round shape due to the photoresist reflow characteristics. Resistivity of carbon thin film pyrolyzed at 1000 °C was 3 mΩ cm, which is comparable to that of highly boron-doped polysilicon. The pyrolysis temperature of 1000 °C was chosen in order to obtain carbon film with high conductivity for use as a working electrode. Thrombin aptamer was grafted onto the pyrolyzed carbon surface using carbodiimide-mediated chemistry, followed by Triton-X 100 and BSA treatment to reduce non-specific binding of thrombin. Electron-transfer resistance changes due to thrombin binding onto the carbon surface were measured using electrochemical impedance spectroscopy techniques. Thrombin concentrations between 0.5 nM and 500 nM were detected by electrochemical measurement. Pyrolyzed carbon can provide a new approach for miniaturization, integration, and low-cost fabrication in electrochemical biosensors.
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- 2008
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24. Fabrication and Characterization of Pyrolyzed Carbon for Use as an Electrode Material in Electrochemical Biosensor
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Jung A Lee, Juhyoun Kwak, Se Il Park, Kwang-Cheol Lee, Seung-Seob Lee, and Seongpil Hwang
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Electrode material ,Fabrication ,Materials science ,chemistry ,Mechanical Engineering ,Electrochemical biosensor ,chemistry.chemical_element ,Nanotechnology ,Pyrolysis ,Carbon ,Characterization (materials science) - Published
- 2007
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25. Fabrication and characteristics of micro-machined thermoelectric flow sensor
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Young-Hwa Lee, Sung-Cheoul Roh, Kwang-Chul Lee, Kook-Jin Kim, Se Il Park, Yong-Moon Choi, Pil-Sun Na, and Young-Eon Ihm
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Bulk micromachining ,Materials science ,Fabrication ,Thermocouple ,Semiconductor device fabrication ,business.industry ,Thermoelectric effect ,Electrical engineering ,Optoelectronics ,Wafer ,business ,Volumetric flow rate ,Voltage - Abstract
A thermoelectric flow sensor for small quantity of gas flow rate was fabricated using silicon wafer semiconductor process and bulk micromachining technology. Evanohm R alloy heater and chromel-constantan thermocouples were used as a generation heat unit and sensing parts, respectively. The heater and thermocouples are thermally isolated on the laminated membrane. The characteristics of this sensor were observed in the flow rate range from 0.2 slm to 1.0 slm and the heater power from 0.72 mW to 5.63 mW. The results showed that the sensitivities : voltage difference, : flow rate) were increased in accordance with heater power rise and decreasing of flow rate.
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- 2005
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26. Fabrication and Characteristics of Chromel-Constantan Multijunction Thermal Converter with Evanohm R Alloy Heater
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Young-Eon Ihm, Young-Hwa Lee, Se Il Park, Sung-Won Kwon, and Kook-Jin Kim
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Chromel ,Bulk micromachining ,Materials science ,Fabrication ,business.industry ,Constantan ,Thermocouple ,Electrical engineering ,Optoelectronics ,Wafer ,business ,500 kHz ,Temperature coefficient - Abstract
A thin-film multijunction thermal converter was fabricated through the process using 6 inch silicon wafer semiconductor process and bulk micromachining. Evanohm R alloy and chromel-constantan were used as a heater and thermocouple materials, respectively. The temperature coefficient of resistance of Evanohm R heater was about 75.12 ppm/ and the voltage sensitivity of the thermal converter indicated about 5.75 mV/mW in air. The transfer differences, measured by FRDC-DC method in the frequency range from 20 Hz to 10 kHz, showed the value under about 1.36 ppm, 0.83 ppm for the film thickness of 500, 200 nm, respectively. And in case of a 200 nm-thick thermal converter, the AC-DC transfer differences seems to be stabilized below the value of 1 ppm in the frequency range from 1 kHz to 500 kHz.
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- 2004
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27. Chromel-Alumel Thermoelectric Flow Sensor Fabricated on Dielectric(Si3N4/SiO2/Si3N4) Membrane
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Jung-Hee Lee, Hyung-Ju Lee, Yeo-Hwan Kim, Yong-Moon Choi, Jin-Sup Kim, and Se Il Park
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Chromel ,Thermal conductivity ,Alumel ,Materials science ,Thermocouple ,Seebeck coefficient ,Thermoelectric effect ,Analytical chemistry ,engineering ,Dielectric ,Composite material ,engineering.material ,Temperature coefficient - Abstract
A chromel-alumel thermoelectric flow sensor using thermal isolation membrane was fabricated. Temperature coefficient of resistance of thin film Pt-heater was about , and Seebeck coefficient of chromel-alumel thermocouple was about . The sensor showed that thermoelectric voltage decreased as thermal conductivity of gas increased, and -flow sensitivity increased as heater voltage increased or the distance between heater and thermocouple decreased. When heater voltage was about 2.5 V, -flow sensitivity and thermal response time of the sensor were about and 0.18 sec., respectively. Linear range in flow sensitivity of the flow sensor was wider than that of Bi-Sb flow sensor.
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- 2003
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28. Development of 10-v josephson series arrays
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Se Il Park and Hyun Kwon Hong
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Josephson effect ,Materials science ,business.industry ,Attenuation ,Electrical engineering ,Pi Josephson junction ,Optoelectronics ,Superconducting tunnel junction ,Electrical and Electronic Engineering ,business ,Instrumentation ,Stripline ,Microwave ,Voltage ,Electronic circuit - Abstract
Developed a new fabrication process for 10-V Josephson junction series arrays (JJAs). A plasma nitridation process is employed for reducing the microwave attenuation in the Josephson microstripline. Improvements of microwave attenuation are about 2 dB for test arrays of 2000, 3000, and 4000 Josephson junctions in a single stripline. We obtained stable quantized voltage steps up to 12 V at 76.4 and 86.8 GHz with step amplitudes of more than 5 /spl mu/A and stability times of more than 5 min. The circuits used 14 648 junctions arranged in 8 parallel paths.
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- 2003
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29. Fabrication of Thick Silicon Dioxide Air-Bridge and Coplanar Waveguide for RF Application Using Complex Oxidation Process and MEMS Technology
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Bong-Hee Lee, Dongin Lee, Jeong-Yong Park, Yong-Hok Bae, Se Il Park, Jong-Hyun Lee, and Kook-Jin Kim
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Microelectromechanical systems ,Thermal oxidation ,Materials science ,Silicon ,business.industry ,Coplanar waveguide ,chemistry.chemical_element ,Substrate (electronics) ,Surface micromachining ,chemistry ,Etching (microfabrication) ,Electronic engineering ,Optoelectronics ,Insertion loss ,business - Abstract
This paper proposes a thick oxide air-bridge structure which can be used as a substrate for RF circuits. The structure was fabricated by anodic reaction, complex oxidation and micromachining technology using TMAH etching. High quality films were obtained by combining low temperature thermal oxidation (, 1 hr at ) and rapid thermal oxidation (RTO) process (, 2 min). This structure is mechanically stable because of thick oxide layer up to and is expected to solve the problem of high dielectric loss of silicon substrate in RF region. The properties of the transmission line formed on the oxidized porous silicon (OPS) air-bridge were investigated and compared with those of the transmission line formed on the OPS layers. The insertion loss of coplanar waveguide (CPW) on OPS air-bridge was (about 2dB) lower than that of CPW on OPS layers. Also, the return loss of CPW on OPS air-bridge was less than about -20 dB at measured frequency region for 2.2 mm. Therefore, this technology is very promising for extending the use of CMOS circuitry to higher RF frequencies.
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- 2002
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30. Thin Film Multijunction Thermal Converter for Low Input Voltage with Low Frequency
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Hyung-Ju Lee, Jin-Sup Kim, Sung-Won Kwon, Chan-Soon Hwang, Jung-Hee Lee, and Se Il Park
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Forward converter ,Materials science ,business.industry ,Boost converter ,Thermoelectric effect ,Buck–boost converter ,Ćuk converter ,Electrical engineering ,Optoelectronics ,Low frequency ,Thin film ,business ,Voltage - Abstract
NiCr-heaters with three different thicknesses ranging from 400 nm to 800 nm were fabricated and their characteristics were compared for the purpose of developing a chromel-alumel multijunction thermal converter for low input voltage with low frequency. The thermoelectric effect-induced AC-DC voltage transfer difference of the thermal converter with a built-in NiCr-heater of 400 nm-thickness was in the DC reversing frequency of with appling and the difference was increased to in the frequency of , when both thermoelectric effects and frequency effects were considered, showing the thermal converter would be suitable for the low input voltage application with low frequency.
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- 2002
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31. A planar Bi-Sb multijunction thermal converter with small ac-dc transfer differences
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Hyun-Cheol Lee, Se-Il Park, Jung-Hee Lee, Jong-Hyun Lee, Jin-Sup Kim, and Sung-Won Kwon
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Bulk micromachining ,Materials science ,Silicon ,business.industry ,Bifilar coil ,Electrical engineering ,chemistry.chemical_element ,Substrate (electronics) ,Thermopile ,Responsivity ,chemistry ,Thermoelectric effect ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Instrumentation ,Voltage - Abstract
A planar Bi-Sb multijunction thermal converter was fabricated on the LPCVD Si/sub 3/N/sub 4//SiO/sub 2//Si/sub 3/N/sub 4/-diaphragm, prepared by silicon bulk micromachining, which thermally isolated a bifilar Pt- or NiCr-heater and the hot junctions of a Bi-Sb thermopile from the silicon substrate. The voltage responsivity, the ac-dc transfer difference, and the fluctuations of the output thermoelectric voltage and heater resistance were discussed to investigate the design factors of a thermal converter. The respective voltage responsivities in air and in a vacuum of the thermal converter with a built-in NiCr-heater were about 14.0 mV/mW and 54.0 mV/mW. The ac-dc voltage and the current transfer differences in air were about /spl plusmn/0.60 ppm and /spl plusmn/0.11 ppm in the dc reversing frequency range from 10 Hz to 10 kHz. They are sufficiently small to be used as practical ac standards. Compared to the thermal converter with a built-in Pt-heater, the thermal converter with a built-in NiCr-heater demonstrated a higher voltage responsivity and smaller ac-dc transfer differences, while exhibiting slightly larger fluctuations in output thermoelectric voltage and in heater resistance.
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- 2002
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32. Apoptosis imaging studies in various animal models using radio-iodinated peptide
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Nisarg Soni, Yeong Su Ha, Se-Il Park, Heesu Ahn, In San Kim, Wonjung Kwak, Byung-Heon Lee, Woonghee Lee, Jeongsoo Yoo, and Gwang Il An
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Cancer Research ,Biodistribution ,Pathology ,medicine.medical_specialty ,Programmed cell death ,Lung Neoplasms ,medicine.medical_treatment ,Clinical Biochemistry ,Pharmaceutical Science ,Mice, Nude ,Apoptosis ,Histones ,Iodine Radioisotopes ,Rats, Sprague-Dawley ,In vivo ,Annexin ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Doxorubicin ,Pharmacology ,Chemotherapy ,Mice, Inbred BALB C ,Antibiotics, Antineoplastic ,business.industry ,Biochemistry (medical) ,Cell Biology ,Imaging agent ,Molecular Imaging ,Disease Models, Animal ,Isotope Labeling ,Cancer research ,Heterografts ,business ,Peptides ,Biomarkers ,medicine.drug - Abstract
Apoptosis has a role in many medical disorders and treatments; hence, its non-invasive evaluation is one of the most riveting research topics. Currently annexin V is used as gold standard for imaging apoptosis. However, several drawbacks, including high background, slow body clearance, make it a suboptimum marker for apoptosis imaging. In this study, we radiolabeled the recently identified histone H1 targeting peptide (ApoPep-1) and evaluated its potential as a new apoptosis imaging agent in various animal models. ApoPep-1 (CQRPPR) was synthesized, and an extra tyrosine residue was added to its N-terminal end for radiolabeling. This peptide was radiolabeled with (124)I and (131)I and was tested for its serum stability. Surgery- and drug-induced apoptotic rat models were prepared for apoptosis evaluation, and PET imaging was performed. Doxorubicin was used for xenograft tumor treatment in mice, and the induced apoptosis was studied. Tumor metabolism and proliferation were assessed by [(18)F]FDG and [(18)F]FLT PET imaging and compared with ApoPep-1 after doxorubicin treatment. The peptide was radiolabeled at high purity, and it showed reasonably good stability in serum. Cell death was easily imaged by radiolabeled ApoPep-1 in an ischemia surgery model. And, liver apoptosis was more clearly identified by ApoPep-1 rather than [(124)I]annexin V in cycloheximide-treated models. Three doxorubicin doses inhibited tumor growth, which was evaluated by 30-40% decreases of [(18)F]FDG and [(18)F]FLT PET uptake in the tumor area. However, ApoPep-1 demonstrated more than 200% increase in tumor uptake after chemotherapy, while annexin V did not show any meaningful uptake in the tumor compared with the background. Biodistribution data were also in good agreement with the microPET imaging results. All of the experimental data clearly demonstrated high potential of the radiolabeled ApoPep-1 for in vivo apoptosis imaging.
- Published
- 2014
33. Baicalein inhibits agonist- and tumor cell-induced platelet aggregation while suppressing pulmonary tumor metastasis via cAMP-mediated VASP phosphorylation along with impaired MAPKs and PI3K-Akt activation
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Hyun Dong Ji, Se Il Park, Chang Geun Lee, Kyu Sung Heo, Ji Sue Baik, You Soo Park, Young Ji Lee, Kwangmo Yang, Man Hee Rhee, Sung Dae Kim, Joeng Yoon Han, and Joong Sun Kim
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Male ,Platelet Aggregation ,Biochemistry ,Metastasis ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Mice ,Phosphatidylinositol 3-Kinases ,Random Allocation ,Cell Line, Tumor ,Cyclic AMP ,Medicine ,Animals ,Platelet activation ,Kinase activity ,Enzyme Inhibitors ,Phosphorylation ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Phosphoinositide-3 Kinase Inhibitors ,Pharmacology ,Mice, Inbred BALB C ,biology ,business.industry ,Microfilament Proteins ,biology.organism_classification ,medicine.disease ,Phosphoproteins ,Xenograft Model Antitumor Assays ,Baicalein ,Rats ,Enzyme Activation ,chemistry ,Immunology ,Flavanones ,Cancer research ,Scutellaria baicalensis ,Mitogen-Activated Protein Kinases ,business ,Cell Adhesion Molecules ,Proto-Oncogene Proteins c-akt - Abstract
Recently, the importance of platelet activation in cancer metastasis has become generally accepted. As a result, the development of new platelet inhibitors with minimal adverse effects is now a promising area of targeted cancer therapy. Baicalein is a functional ingredient derived from the root of Scutellaria baicalensis Georgi, a plant used intraditional medicine. The pharmacological effects of this compound including anti-oxidative and anti-inflammatory activities have already been demonstrated. However, its effects on platelet activation are unknown. We therefore investigated the effects of baicalein on ligand-induced platelet aggregation and pulmonary cancer metastasis. In the present study, baicalein inhibited agonist-induced platelet aggregation, granule secretion markers (P-selectin expression and ATP release), [Ca(2+)]i mobilization, and integrin αIIbβ3 expression. Additionally, baicalein attenuated ERK2, p38, and Akt activation, and enhanced VASP phosphorylation. Indeed, baicalein was shown to directly inhibit PI3K kinase activity. Moreover, baicalein attenuated the platelet aggregation induced by C6 rat glioma tumor cells in vitro and suppressed CT26 colon cancer metastasis in mice. These features indicate that baicalein is a potential therapeutic drug for the prevention of cancer metastasis.
- Published
- 2014
34. Salivary Mucocele with Osseous Metaplasia in a Dog
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Jin-Kyu Park, Jung-Youn Han, Ae-Ri Ji, Kyu-Shik Jeong, Dong-Hag Choi, Se-Il Park, Tae-Hwan Kim, Kyung-Sook Hong, Ok-Kyung Hwang, Il-Hwa Hong, and Mi-Ran Ki
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Male ,Metaplasia ,Pathology ,medicine.medical_specialty ,General Veterinary ,Ossification ,business.industry ,Ossification, Heterotopic ,Mucin ,Mucocele ,Granulation tissue ,Connective tissue ,Salivary Gland Diseases ,Anatomy ,Mucus ,Dogs ,medicine.anatomical_structure ,Salivary mucocele ,medicine ,Animals ,Dog Diseases ,Osseous metaplasia ,medicine.symptom ,business - Abstract
A 4-year-old, male, dachshund was referred to a certain local veterinary hospital because of a soft and fluctuant swelling in the left upper cervical region. The swelling was surgically removed and appeared to be filled with bloody mucus. Grossly, the swelling was identified as salivary mucocele and showed small multifocal whitish ossified tissue on its surface. Microscopically, the wall of salivary mucocele appeared as granulation tissue surrounding mucin, which was composed of loose edematous and vascularized connective tissue containing chronic inflammatory cells such as lymphocytes, plasma cells and macrophages. Characteristically, present case had ossifying components formed by metaplastic spindle cells in the wall of salivary mucocele. Therefore, the present case was diagnosed as salivary mucocele with osseous metaplasia in a dog.
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- 2009
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35. All-niobium process for Josephson series array circuits
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Kyu-Tae Kim, Se Il Park, and Rae Duk Lee
- Subjects
Josephson effect ,Materials science ,Fabrication ,business.industry ,Anodizing ,Annealing (metallurgy) ,Niobium ,Electrical engineering ,chemistry.chemical_element ,chemistry ,Optoelectronics ,Critical current ,Electrical and Electronic Engineering ,business ,Instrumentation ,Electronic circuit ,Voltage - Abstract
We have developed a new fabrication process for integrated Nb/Al/sub 2/O/sub 3//Nb Josephson series arrays using the selective niobium anodization process (SNAP), the image reversal technique (IRT) and lift-off. To avoid chaotic behavior, the critical current of the array was decreased by post-fabrication annealing or the in situ multilayer oxidation process. In the frequency range 70-100 GHz, the array containing 2520 junctions produced stable quantized voltage steps up to 2 V with step widths of 40-100 /spl mu/A and stability times of more than 4 h. >
- Published
- 1995
- Full Text
- View/download PDF
36. The fabrication of carbon nanostructures using electron beam resist pyrolysis and nanomachining processes for biosensing applications
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Se Il Park, Kwang-Cheol Lee, Seung S. Lee, and Jung A Lee
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Materials science ,Mechanical Engineering ,technology, industry, and agriculture ,Oxide ,Nanowire ,chemistry.chemical_element ,Bioengineering ,Nanotechnology ,General Chemistry ,chemistry.chemical_compound ,Nanolithography ,chemistry ,Resist ,Mechanics of Materials ,Etching (microfabrication) ,General Materials Science ,Electrical and Electronic Engineering ,Carbon ,Pyrolysis ,Electron-beam lithography - Abstract
We present a facile, yet versatile carbon nanofabrication method using electron beam lithography and resist pyrolysis. Various resist nanopatterns were fabricated using a negative electron beam resist, SAL-601, and they were then subjected to heat treatment in an inert atmosphere to obtain carbon nanopatterns. Suspended carbon nanostructures were fabricated by the wet-etching of an underlying sacrificial oxide layer. Free-standing carbon nanostructures, which contain 130 nm wide, 15 nm thick, and 4 µm long nanobridges, were fabricated by resist pyrolysis and nanomachining processes. Electron beam exposure dose effects on resist thickness and pattern widening were studied. The thickness of the carbon nanostructures was thinned down by etching with oxygen plasma. An electrical biosensor utilizing carbon nanostructures as a conducting channel was studied. Conductance modulations of the carbon device due to streptavidin–biotin binding and pH variations were observed.
- Published
- 2011
37. Achromatic thin-film polarization-preserving beam displacers stable for thickness variations
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Se Il Park
- Subjects
Materials science ,business.industry ,Materials Science (miscellaneous) ,Polarization (waves) ,Industrial and Manufacturing Engineering ,law.invention ,Optics ,Achromatic lens ,law ,Light beam ,sense organs ,Business and International Management ,Thin film ,skin and connective tissue diseases ,business ,Refractive index ,Near infrared radiation - Abstract
A pair of two-layer-coated totally reflecting thin-film systems that mutually compensate for the polarization changes and have a good stability for the thickness errors is investigated.
- Published
- 2010
38. Morphological abnormalities, impaired fetal development and decrease in myostatin expression following somatic cell nuclear transfer in dogs
- Author
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Il-Hwa, Hong, Yeon-Woo, Jeong, Taeyoung, Shin, Sang-Hwan, Hyun, Jin-Kyu, Park, Mi-Ran, Ki, Seon-Young, Han, Se-Il, Park, Ji-Hyun, Lee, Eun-Mi, Lee, Ah-Young, Kim, Sang-Young, You, Woo-Suk, Hwang, and Kyu-Shik, Jeong
- Subjects
Nuclear Transfer Techniques ,Dogs ,Macroglossia ,Cloning, Organism ,Muscles ,Animals ,RNA, Messenger ,Myostatin ,Embryo, Mammalian ,Muscle Development ,Polymerase Chain Reaction - Abstract
Several mammals, including dogs, have been successfully cloned using somatic cell nuclear transfer (SCNT), but the efficiency of generating normal, live offspring is relatively low. Although the high failure rate has been attributed to incomplete reprogramming of the somatic nuclei during the cloning process, the exact cause is not fully known. To elucidate the cause of death in cloned offspring, 12 deceased offspring cloned by SCNT were necropsied. The clones were either stillborn just prior to delivery or died with dyspnea shortly after birth. On gross examination, defects in the anterior abdominal wall and increased heart and liver sizes were found. Notably, a significant increase in muscle mass and macroglossia lesions were observed in deceased SCNT-cloned dogs. Interestingly, the expression of myostatin, a negative regulator of muscle growth during embryogenesis, was down-regulated at the mRNA level in tongues and skeletal muscles of SCNT-cloned dogs compared with a normal dog. Results of the present study suggest that decreased expression of myostatin in SCNT-cloned dogs may be involved in morphological abnormalities such as increased muscle mass and macroglossia, which may contribute to impaired fetal development and poor survival rates.
- Published
- 2010
39. Luminescence imaging using radionuclides: a potential application in molecular imaging
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Eun Kyung Wang, Yeong Su Ha, Jung Young Kim, Se-Il Park, Kyeong Min Kim, Jaetae Lee, Jeongsoo Yoo, Hong Joo Kim, Jeong Chan Park, Michael J. Welch, Gwang Il An, and Jungmin Oh
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Cancer Research ,High energy ,Optical Phenomena ,Arabidopsis ,Antibodies, Monoclonal, Humanized ,Mice ,Optical imaging ,Nuclear magnetic resonance ,Cell Line, Tumor ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Radionuclide Imaging ,Cherenkov radiation ,Radionuclide ,medicine.diagnostic_test ,Chemistry ,Antibodies, Monoclonal ,Trastuzumab ,Molecular Imaging ,Functional imaging ,Positron emission tomography ,Positron-Emission Tomography ,Luminescent Measurements ,Molecular Medicine ,Molecular imaging ,Luminescence - Abstract
Introduction Nuclear and optical imaging are complementary in many aspects and there would be many advantages when optical imaging probes are prepared using radionuclides rather than classic fluorophores, and when nuclear and optical dual images are obtained using single imaging probe. Methods The luminescence intensities of various radionuclides having different decay modes have been assayed using luminescence imaging and in vitro luminometer. Radioiodinated Herceptin was injected into a tumor-bearing mouse, and luminescence and microPET images were obtained. The plant dipped in [ 32 P]phosphate solution was scanned in luminescence mode. Radio-TLC plate was also imaged in the same imaging mode. Results Radionuclides emitting high energy β + /β − particles showed higher luminescence signals. NIH3T6.7 tumors were detected in both optical and nuclear imaging. The uptake of [ 32 P]phosphate in plant was easily followed by luminescence imaging. Radio-TLC plate was visualized and radiochemical purity was quantified using luminescence imaging. Conclusion Many radionuclides with high energetic β + or β − particles during decay were found to be imaged in luminescence mode due mainly to Cerenkov radiation. ‘Cerenkov imaging’ provides a new optical imaging platform and an invaluable bridge between optical and nuclear imaging. New optical imaging probes could be easily prepared using well-established radioiodination methods. Cerenkov imaging will have more applications in the research field of plant science and autoradiography.
- Published
- 2010
40. Fabrication of carbon nanomechanical resonators with embedded single walled carbon nanotube stiffening layers
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Kwang-Cheol Lee, Se Il Park, Bumki Min, Seunghoon Lee, and Seung S. Lee
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Materials science ,Fabrication ,business.industry ,chemistry.chemical_element ,Young's modulus ,Nanotechnology ,Carbon nanotube ,law.invention ,symbols.namesake ,Resist ,chemistry ,law ,Etching (microfabrication) ,symbols ,Optoelectronics ,Dry etching ,business ,Carbon ,Electron-beam lithography - Abstract
This study presents a new fabrication method for high frequency nanomechanical resonators by utilizing carbon layers with embedded single walled carbon-nanotube layers. The carbon layers, fabricated by pyrolysis of photo- or electron beam resists, showed low-density and moderate Young's modulus which is suitable to sensitive nanodevices. The carbon-nanotube layers underneath carbon layers enhanced conductivity and Young's modulus while maintaining low-density of carbon nanoresonators. These two layers are fashioned into doubly clamped nanomechanical beams by electron beam lithography and carbon dry etching processes. Dynamic behaviors such as resonant frequency and Q-factor are investigated using magnetomotive detection method.
- Published
- 2010
- Full Text
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41. Potent neutralization of vacuolating cytotoxin (VacA) of Helicobacter pylori by immunoglobulins against the soluble recombinant VacA
- Author
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Mi-Ran, Ki, Il-Hwa, Hong, Jin-Kyu, Park, Kyung-Sook, Hong, Ok-Kyung, Hwang, Jung-Yuan, Han, Ae-Ri, Ji, Se-Il, Park, Seung-Keun, Lee, Sung-Eun, Yoo, and Kyu-Shik, Jeong
- Subjects
Helicobacter pylori ,Recombinant Fusion Proteins ,Immunoblotting ,Antibodies, Bacterial ,Helicobacter Infections ,Mice, Inbred C57BL ,Mice ,Bacterial Proteins ,Stomach Neoplasms ,Vacuoles ,Tumor Cells, Cultured ,Animals ,Humans ,Female ,Immunization ,Rabbits - Abstract
The recombinant vacuolating cytotoxin (rVacA) of Helicobacter pylori that retains native conformational epitopes was evaluated as a vaccine antigen for anti-H. pylori treatment.s1m1 vacA gene fraction encoding the mature VacA protein was expressed as a soluble protein in E. coli at low temperature. The efficacy of anti-rVacA antibody against VacA or H. pylori was assessed in vitro using AGS cells and in vivo using a murine model.The rabbit antisera against rVacA completely neutralized the vacuolating activity and partially inhibited the cell death induced by VacA in AGS cells. Oral immunization of C57BL/6 mice with rVacA plus CpG-oligodeoxynucleotide (ODN) as an ajuvant stimulated specific anti-VacA antibody and mucosal immune responses which correlated with decreased systemic immune responses and gastric urease activities (p0.05).The rVacA antigen possessing conformational epitopes may have potential as a vaccine component and may be useful in serological and histopathological analysis.
- Published
- 2009
42. Enhancement of Coulomb blockade and tunability by multidot coupling in a silicon-on-insulator-based single-electron transistor
- Author
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B. T. Lee, K. S. Park, Jang-Han Kim, Kyu-Tae Kim, C. H. Lee, Kyung Hwa Yoo, Sangchul Oh, Sun-Kyun Lee, Se Il Park, Jong Wan Park, Jin-Gyu Kim, and Jung B. Choi
- Subjects
Physics ,Physics and Astronomy (miscellaneous) ,Condensed matter physics ,Coupling strength ,Transistor ,Coulomb blockade ,Silicon on insulator ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,law.invention ,Nonlinear system ,Coupling (physics) ,Quantum dot ,law ,Quantum tunnelling - Abstract
A dual-gate-controlled single-electron transistor with coupled dot geometry has been fabricated on a silicon-on-insulator structure. Coupled dots are defined by tunable gates which are designed to separately control the tunneling potential barriers to compensate for disorder due to size fluctuation in quantum dots. The Coulomb-blockade phenomena observed in linear and nonlinear transport regimes were found to be enhanced by the multidot coupling. The Coulomb staircase (nonlinear effect) appears more clearly with the increasing number of coupled dots, indicating definite suppression of the inevitable cotunneling process. In the linear regime, the frequency of Coulomb oscillation was able to be tuned by changing the interdot coupling strength. These results indicate that enhancement of the Coulomb blockade and tunability can be achieved through replacing the traditional single dot by gate-controlled multidots in future single-electron devices.
- Published
- 1999
- Full Text
- View/download PDF
43. Development of Advanced Atherosclerotic Plaque by Injection of Inflammatory Proteins in a Rabbit Iliac Artery Model
- Author
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Se Hoon Kim, Yangsoo Jang, Seul Gee Lee, Se-Il Park, Myeong Ki Hong, Jaewon Oh, Sungha Park, Sang Hak Lee, Sung Yu Hong, Young Guk Ko, Donghoon Choi, and Jung Sun Kim
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Pathology ,Cardiac & Cardiovascular Systems ,medicine.medical_treatment ,Sodium Chloride ,030204 cardiovascular system & hematology ,HMGB1 ,Iliac Artery ,Cholesterol, Dietary ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,balloon injury ,In vivo ,medicine ,Animals ,Endothelium ,HMGB1 Protein ,Olive Oil ,Saline ,Rabbit model ,biology ,Tumor Necrosis Factor-alpha ,Cholesterol ,business.industry ,Macrophages ,General Medicine ,inflammatory protein ,Plaque, Atherosclerotic ,Pathophysiology ,Disease Models, Animal ,Catheter ,030104 developmental biology ,Injections, Intra-Arterial ,chemistry ,biology.protein ,Original Article ,Tumor necrosis factor alpha ,Rabbits ,Radiology ,atherosclerosis ,business ,Tomography, Optical Coherence - Abstract
Purpose Appropriate animal models of atherosclerotic plaque are crucial to investigating the pathophysiology of atherosclerosis, as well as for the evaluation of the efficacy and safety of vascular devices. We aimed to develop a novel animal model that would be suitable for the study of advanced atherosclerotic lesions in vivo. Materials and Methods Atherosclerotic plaque was induced in 24 iliac arteries from 12 rabbits by combining a high cholesterol diet, endothelial denudation, and injection into the vessel wall with either saline (n=5), olive oil (n=6), or inflammatory proteins [n=13, high-mobility group protein B1 (HMGB1) n=8 and tumor necrosis factor (TNF)-α n=5] using a Cricket™ Micro-infusion catheter. Optical coherence tomography (OCT) was performed to detect plaque characteristics after 4 weeks, and all tissues were harvested for histological evaluation. Results Advanced plaque was more frequently observed in the group injected with inflammatory proteins. Macrophage infiltration was present to a higher degree in the HMGB1 and TNF-α groups, compared to the oil or saline group (82.1±5.1% and 94.6±2.2% compared to 49.6±14.0% and 46.5±9.6%, p-value
- Published
- 2016
- Full Text
- View/download PDF
44. Pyrolyzed carbon biosenosor for aptamer-protein interactions using electrochemical impedance spectroscopy
- Author
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Seongpil Hwang, Joohan Lee, Se Il Park, Kwang-Cheol Lee, Juhyoun Kwak, and Seung S. Lee
- Subjects
Materials science ,Working electrode ,Aptamer ,Thermal decomposition ,technology, industry, and agriculture ,Analytical chemistry ,chemistry.chemical_element ,Photoresist ,Electrochemistry ,Dielectric spectroscopy ,chemistry ,Chemical engineering ,Carbon ,Biosensor - Abstract
We present an electrochemical biosensor utilizing pyrolyzed carbon as a working electrode for the aptamer-based thrombin detection. The pyrolyzed carbon is fabricated by photolithography and thermal decomposition of photoresist in an N2 atmosphere. Physical and electrical properties of carbon thin film pyrolyzed with a positive photoresist, AZ9260, were studied for the biosensor application. Electron transfer resistance changes due to thrombin binding onto the carbon surface modified with thrombin aptamer were measured using electrochemical impedance spectroscopy techniques. Thrombin concentrations between 0.5 nM and 500 nM were detected by the electrochemical measurements.
- Published
- 2007
- Full Text
- View/download PDF
45. Real-time Detection of Protein Interactions Using Pyrolyzed Carbon
- Author
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Joohan Lee, Se Il Park, Seung-Seob Lee, and Kwang-Cheol Lee
- Subjects
Streptavidin ,Aqueous solution ,Materials science ,Thermal decomposition ,technology, industry, and agriculture ,Analytical chemistry ,chemistry.chemical_element ,Photoresist ,law.invention ,chemistry.chemical_compound ,Biotin ,chemistry ,Chemical engineering ,law ,Photolithography ,Pyrolysis ,Carbon - Abstract
We present label-free, real-time detection of streptavidin binding using the pyrolyzed carbon with a p-type conduction behavior in aqueous solution, which is functionalized with amine-conjugated biotin. Pyrolyzed carbon derived from AZ 5214E are fabricated by photolithography and photoresist thermal decomposition in a N2 atmosphere. The streptavidin-biotin interactions on the pyrolyzed carbon are detected successfully by current change after streptavidin binding.
- Published
- 2006
- Full Text
- View/download PDF
46. Generating Upward Mobility: The Case of Korea and Private Sector Development
- Author
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Se-il Park
- Subjects
Labour economics ,Equity (economics) ,ComputingMilieux_THECOMPUTINGPROFESSION ,Economic inequality ,Private sector development ,Business ,Private sector ,Industrial relations ,Social mobility ,Management - Abstract
Employment creation is the best way to achieve growth and equity at the same time: namely, “shared growth.” Yet it is not the sheer number of jobs, but the quality of newly created jobs, that is most important in the development process. Simply put, what matters is the number of good jobs created. Good jobs imply high-productivity, high-paying jobs with the possibility of promotion. In this regard, and in its particular path of private sector-led development, Korea has abundant lessons to offer.
- Published
- 2003
- Full Text
- View/download PDF
47. A simple 10:1 divider for precision measurement of 10 V by an 1 V standard
- Author
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Sung-Won Kwon, Kyu Tae Kim, Yong Myung Cho, and Se Il Park
- Subjects
Engineering ,business.industry ,Voltage divider ,Calibration ,Electrical engineering ,Zener diode ,Current source ,business ,Clipper (electronics) ,Voltage reference - Abstract
We developed an easy-to-operate 10:1 voltage divider system which enables to calibrate the Zener voltage standard's 10 V output within an uncertainty of a few parts in 10/sup 8/ with well established 1 V standard like 1 V Josephson array. Using a Zener voltage standard for a 10-V current source of the divider, the ratio calibration became simple and easy without losing any significant accuracy. The estimated uncertainty of 10:1 ratio calibration is about 0.006 ppm (1 U/sub c/).
- Published
- 2002
- Full Text
- View/download PDF
48. A 10 V calibration system using 1 V Josephson array at KRISS
- Author
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Sung-Won Kwon, Kyu Tae Kim, Se Il Park, and Rae Duk Lee
- Subjects
Josephson effect ,Engineering ,Resistive touchscreen ,business.industry ,Electrical resistivity and conductivity ,Voltage divider ,Measuring instrument ,Calibration ,Electrical engineering ,business ,Voltage ,Electronic circuit - Abstract
A 10 V calibration system at KRISS is described which allows the measurement of 10 V electronic voltage standards using 1 V Josephson array with the help of an automated 10:1 resistive voltage divider system. The overall uncertainty of a measurement (1/spl sigma/) at 10 V is less than 0.1 ppm. >
- Published
- 2002
- Full Text
- View/download PDF
49. High frequency carbon nanomechanical resonators embedded with carbon nanotube stiffening layers
- Author
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Kwang-Cheol Lee, Seunghoon Lee, Bumki Min, Se Il Park, and Seung S. Lee
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,chemistry.chemical_element ,Stiffness ,Modulus ,Young's modulus ,Carbon nanotube ,Fundamental frequency ,law.invention ,Resonator ,symbols.namesake ,chemistry ,law ,Q factor ,medicine ,symbols ,Composite material ,medicine.symptom ,Carbon - Abstract
We present batch-fabricated carbon-based nanomechanical resonators which are laminated by a pyrolyzed carbon layer and single-walled carbon-nanotube network (C/CNT resonators). The embedded CNT layers simultaneously enhance the electrical conductivity (∼160-fold) and mechanical stiffness (10% higher Young’s modulus) compared to nonstiffened carbon-only resonators. Dynamic behaviors of the fabricated C/CNT and carbon-only resonators, including fundamental frequency, Q-factor, and frequency tuning characteristics show comparable performance to the silicon based resonators.
- Published
- 2010
- Full Text
- View/download PDF
50. The correlation of the number and the phase uncertainties in the loop-type single-electron tunneling device
- Author
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Kyung Hwa Yoo, Jinhee Kim, Sangchul Oh, Jeong O. Lee, Ju Jin Kim, Se Il Park, and Kyu-Tae Kim
- Subjects
Physics ,Josephson effect ,Condensed matter physics ,Magnetoresistance ,Oscillation ,Scanning tunneling spectroscopy ,Coulomb blockade ,Biasing ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Electrical and Electronic Engineering ,Order of magnitude ,Quantum tunnelling - Abstract
The electric and the magnetic transport properties of the loop-type Al/Al 2 O 3 /Al single-electron tunneling device were studied. Even for the sample with charging energy about one order of magnitude greater than the Josephson coupling energy, the magnetoresistance showed h /2 e -oscillation at low bias voltage, attributed to the phase-coherent pair tunneling. The behavior of the magnetoresistance depends on the gate voltage, showing large and noiseless oscillations with the even number of excess charges but small and noisy oscillations with the odd number of excess charges in the metal islands.
- Published
- 2000
- Full Text
- View/download PDF
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