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Ahn S, Ahn S, Jang H, Eom K, Kim YJ, Hwang JE, Chung JI, Park JY, Nam S, Choi YH, Joung H. Validation of resonance Raman spectroscopy-measured skin carotenoid status as a biomarker for fruit and vegetable intake in Korean adults. Br J Nutr 2023; 130:1993-2001. [PMID: 37184085 DOI: 10.1017/s0007114523001058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Blood carotenoid concentration measurement is considered the gold standard for fruit and vegetable (F&V) intake estimation; however, this method is invasive and expensive. Recently, skin carotenoid status (SCS) measured by optical sensors has been evaluated as a promising parameter for F&V intake estimation. In this cross-sectional study, we aimed to validate the utility of resonance Raman spectroscopy (RRS)-assessed SCS as a biomarker of F&V intake in Korean adults. We used data from 108 participants aged 20-69 years who completed SCS measurements, blood collection and 3-d dietary recordings. Serum carotenoid concentrations were quantified using HPLC, and dietary carotenoid and F&V intakes were estimated via 3-d dietary records using a carotenoid database for common Korean foods. The correlations of the SCS with serum carotenoid concentrations, dietary carotenoid intake and F&V intake were examined to assess SCS validity. SCS was positively correlated with total serum carotenoid concentration (r = 0·52, 95 % CI = 0·36, 0·64, P < 0·001), serum β-carotene concentration (r = 0·60, 95 % CI = 0·47, 0·71, P < 0·001), total carotenoid intake (r = 0·20, 95 % CI = 0·01, 0·37, P = 0·04), β-carotene intake (r = 0·30, 95 % CI = 0·11, 0·46, P = 0·002) and F&V intake (r = 0·40, 95 % CI = 0·23, 0·55, P < 0·001). These results suggest that SCS can be a valid biomarker of F&V intake in Korean adults.
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Affiliation(s)
- Seoeun Ahn
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul08826, Republic of Korea
| | - Sungmo Ahn
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Hyeongseok Jang
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Kunsun Eom
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Yoon Jae Kim
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Jeong-Eun Hwang
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul08826, Republic of Korea
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Ji In Chung
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul06351, Republic of Korea
| | - Jin-Young Park
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Sunghyun Nam
- Advanced Sensor Lab, Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., Suwon16678, Republic of Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul06351, Republic of Korea
| | - Hyojee Joung
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul08826, Republic of Korea
- Institute of Health and Environment, Seoul National University, Seoul08826, Republic of Korea
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Park JH, Moon HS, Jung HI, Hwang J, Choi YH, Kim JE. Deep learning and clustering approaches for dental implant size classification based on periapical radiographs. Sci Rep 2023; 13:16856. [PMID: 37803022 PMCID: PMC10558577 DOI: 10.1038/s41598-023-42385-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 09/09/2023] [Indexed: 10/08/2023] Open
Abstract
This study investigated two artificial intelligence (AI) methods for automatically classifying dental implant diameter and length based on periapical radiographs. The first method, deep learning (DL), involved utilizing the pre-trained VGG16 model and adjusting the fine-tuning degree to analyze image data obtained from periapical radiographs. The second method, clustering analysis, was accomplished by analyzing the implant-specific feature vector derived from three key points coordinates of the dental implant using the k-means++ algorithm and adjusting the weight of the feature vector. DL and clustering model classified dental implant size into nine groups. The performance metrics of AI models were accuracy, sensitivity, specificity, F1-score, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC-ROC). The final DL model yielded performances above 0.994, 0.950, 0.994, 0.974, 0.952, 0.994, and 0.975, respectively, and the final clustering model yielded performances above 0.983, 0.900, 0.988, 0.923, 0.909, 0.988, and 0.947, respectively. When comparing the AI model before tuning and the final AI model, statistically significant performance improvements were observed in six out of nine groups for DL models and four out of nine groups for clustering models based on AUC-ROC. Two AI models showed reliable classification performances. For clinical applications, AI models require validation on various multicenter data.
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Affiliation(s)
- Ji-Hyun Park
- Department of Prosthodontics, Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul, 03722, Korea
| | - Hong Seok Moon
- Department of Prosthodontics, Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul, 03722, Korea
| | - Hoi-In Jung
- Department of Preventive Dentistry and Public Oral Health, Yonsei University College of Dentistry, Seoul, 03722, Korea
| | - JaeJoon Hwang
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Dental Research Institute, Pusan National University, Busan, 50612, Korea
| | - Yoon-Ho Choi
- School of Computer Science and Engineering, Pusan National University, Busan, 46241, Korea
| | - Jong-Eun Kim
- Department of Prosthodontics, Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul, 03722, Korea.
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Lee D, Cho S, Park C, Park KR, Lee J, Nam J, Ahn K, Park C, Jeon K, Yuh H, Choi W, Lim CH, Kwon T, Min YH, Joo M, Choi YH, Lee JS, Kim C, Kwon S. Fluidic self-assembly for MicroLED displays by controlled viscosity. Nature 2023:10.1038/s41586-023-06167-5. [PMID: 37438523 DOI: 10.1038/s41586-023-06167-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/04/2023] [Indexed: 07/14/2023]
Abstract
Displays in which arrays of microscopic 'particles', or chiplets, of inorganic light-emitting diodes (LEDs) constitute the pixels, termed MicroLED displays, have received considerable attention1,2 because they can potentially outperform commercially available displays based on organic LEDs3,4 in terms of power consumption, colour saturation, brightness and stability and without image burn-in issues1,2,5-7. To manufacture these displays, LED chiplets must be epitaxially grown on separate wafers for maximum device performance and then transferred onto the display substrate. Given that the number of LEDs needed for transfer is tremendous-for example, more than 24 million chiplets smaller than 100 μm are required for a 50-inch, ultra-high-definition display-a technique capable of assembling tens of millions of individual LEDs at low cost and high throughput is needed to commercialize MicroLED displays. Here we demonstrate a MicroLED lighting panel consisting of more than 19,000 disk-shaped GaN chiplets, 45 μm in diameter and 5 μm in thickness, assembled in 60 s by a simple agitation-based, surface-tension-driven fluidic self-assembly (FSA) technique with a yield of 99.88%. The creation of this level of large-scale, high-yield FSA of sub-100-μm chiplets was considered a significant challenge because of the low inertia of the chiplets. Our key finding in overcoming this difficulty is that the addition of a small amount of poloxamer to the assembly solution increases its viscosity which, in turn, increases liquid-to-chiplet momentum transfer. Our results represent significant progress towards the ultimate goal of low-cost, high-throughput manufacture of full-colour MicroLED displays by FSA.
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Affiliation(s)
- Daewon Lee
- Department of Electronics Engineering, Myongji University, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Seongkyu Cho
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Cheolheon Park
- Bio-MAX Institute, Seoul National University, Seoul, Republic of Korea
| | - Kyung Ryoul Park
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea
| | - Jongcheon Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea
| | - Jaewook Nam
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Kwangguk Ahn
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Changseo Park
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Kiseong Jeon
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Hwankuk Yuh
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Wonseok Choi
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Chung Hyun Lim
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Taein Kwon
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Young Hwan Min
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Minho Joo
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Jeong Soo Lee
- Materials and Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Changsoon Kim
- Department of Intelligence and Information, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea.
- Inter-University Semiconductor Research Center, Seoul National University, Seoul, Republic of Korea.
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea.
- Bio-MAX Institute, Seoul National University, Seoul, Republic of Korea.
- Inter-University Semiconductor Research Center, Seoul National University, Seoul, Republic of Korea.
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Choi YH, Kim JS, Byun G. Source localization based on steered frequency-wavenumber analysis for sparse array. J Acoust Soc Am 2023; 153:3065. [PMID: 37222575 DOI: 10.1121/10.0019552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/06/2023] [Indexed: 05/25/2023]
Abstract
When using a sparse array, locating the target signal of a high-frequency component is difficult. Although forecasting the direction in a sparse situation is challenging, the frequency-wavenumber (f-k) spectrum can simultaneously determine the direction and frequency of the analyzed signal. The striation of the f-k spectrum shifts along the wavenumber axis in a sparse situation, which reduces the spatial resolution required to determine the target's direction using the f-k spectrum. In this study, f-k spectra of a high-frequency signal were used for near-field source localization. Snapping shrimp sounds (5-24 kHz) from SAVEX15 (a shallow-water acoustic variability experiment conducted in May 2015) were used as the data source, and a simulation was used to evaluate the proposed method. Beam steering was performed before creating the f-k spectrum to improve spatial resolution. We found that the spatial resolution was improved, and the location of the sound source could be determined when a signal with beam steering was utilized. The shrimp sound from SAVEX15, a near-field broadband signal, was used to determine the shrimp's location (range, 38 m; depth, 100 m) and the tilt of the vertical line array. These results suggest that the proposed analysis helps to accurately estimate the location of sound source.
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Affiliation(s)
- Y H Choi
- Department of Ocean Engineering, Korea Maritime and Ocean University, Busan 49112, Republic of Korea
| | - J S Kim
- Department of Ocean Engineering, Korea Maritime and Ocean University, Busan 49112, Republic of Korea
| | - Gihoon Byun
- Department of Convergence Study on the Ocean Science and Technology, Korea Maritime and Ocean University, Busan 49112, Republic of Korea
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Chang W, Kim J, Kim M, Lee MW, Lim CH, Kim G, Hwang S, Chang J, Min YH, Jeon K, Kim S, Choi YH, Lee JS. Concurrent self-assembly of RGB microLEDs for next-generation displays. Nature 2023; 617:287-291. [PMID: 37138079 DOI: 10.1038/s41586-023-05889-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 02/24/2023] [Indexed: 05/05/2023]
Abstract
MicroLED displays have been in the spotlight as the next-generation displays owing to their various advantages, including long lifetime and high brightness compared with organic light-emitting diode (OLED) displays. As a result, microLED technology1,2 is being commercialized for large-screen displays such as digital signage and active R&D programmes are being carried out for other applications, such as augmented reality3, flexible displays4 and biological imaging5. However, substantial obstacles in transfer technology, namely, high throughput, high yield and production scalability up to Generation 10+ (2,940 × 3,370 mm2) glass sizes, need to be overcome so that microLEDs can enter mainstream product markets and compete with liquid-crystal displays and OLED displays. Here we present a new transfer method based on fluidic self-assembly (FSA) technology, named magnetic-force-assisted dielectrophoretic self-assembly technology (MDSAT), which combines magnetic and dielectrophoresis (DEP) forces to achieve a simultaneous red, green and blue (RGB) LED transfer yield of 99.99% within 15 min. By embedding nickel, a ferromagnetic material, in the microLEDs, their movements were controlled by using magnets, and by applying localized DEP force centred around the receptor holes, these microLEDs were effectively captured and assembled in the receptor site. Furthermore, concurrent assembly of RGB LEDs were demonstrated through shape matching between microLEDs and receptors. Finally, a light-emitting panel was fabricated, showing damage-free transfer characteristics and uniform RGB electroluminescence emission, demonstrating our MDSAT method to be an excellent transfer technology candidate for high-volume production of mainstream commercial products.
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Affiliation(s)
- Wonjae Chang
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea.
| | - Jungsub Kim
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Myoungsoo Kim
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Min Woo Lee
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Chung Hyun Lim
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Gunho Kim
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Sunghyun Hwang
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Jeeyoung Chang
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Young Hwan Min
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Kiseong Jeon
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Soohyun Kim
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea
| | - Jeong Soo Lee
- Materials & Devices Advanced Research Center, LG Electronics, Seoul, Republic of Korea.
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Utaliyeva A, Shin J, Choi YH. Task-Specific Adaptive Differential Privacy Method for Structured Data. Sensors (Basel) 2023; 23:1980. [PMID: 36850576 PMCID: PMC9966464 DOI: 10.3390/s23041980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Data are needed to train machine learning (ML) algorithms, and in many cases often include private datasets that contain sensitive information. To preserve the privacy of data used while training ML algorithms, computer scientists have widely deployed anonymization techniques. These anonymization techniques have been widely used but are not foolproof. Many studies showed that ML models using anonymization techniques are vulnerable to various privacy attacks willing to expose sensitive information. As a privacy-preserving machine learning (PPML) technique that protects private data with sensitive information in ML, we propose a new task-specific adaptive differential privacy (DP) technique for structured data. The main idea of the proposed DP method is to adaptively calibrate the amount and distribution of random noise applied to each attribute according to the feature importance for the specific tasks of ML models and different types of data. From experimental results under various datasets, tasks of ML models, different DP mechanisms, and so on, we evaluate the effectiveness of the proposed task-specific adaptive DP method. Thus, we show that the proposed task-specific adaptive DP technique satisfies the model-agnostic property to be applied to a wide range of ML tasks and various types of data while resolving the privacy-utility trade-off problem.
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Kim TJ, Pyo JH, Lee H, Choi SC, Min YW, Min BH, Lee JH, Rhee PL, Song M, Choi YH, Kim JJ. Outcomes of Endoscopic Resection for Early Gastric Cancer in Very Elderly Patients: A Nationwide Population-Based Study. Gut Liver 2022:gnl210430. [PMID: 36578192 DOI: 10.5009/gnl210430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 08/20/2022] [Accepted: 08/26/2022] [Indexed: 12/30/2022] Open
Abstract
Background/Aims Few studies have investigated the long-term outcomes of endoscopic resection for early gastric cancer (EGC) in very elderly patients. The aim of this study was to determine the appropriate treatment strategy and identify the risk factors for mortality in these patients. Methods Patients with EGC who underwent endoscopic resection from 2006 to 2017 were identified using National Health Insurance Data and divided into three age groups: very elderly (≥85 years), elderly (65 to 84 years), and non-elderly (≤64 years). Their long- and short-term outcomes were compared in the three age groups, and the survival in the groups was compared with that in the control group, matched by age and sex. We also evaluated the risk factors for long- and short-term outcomes. Results A total of 8,426 patients were included in our study: 118 very elderly, 4,583 elderly, and 3,725 non-elderly. The overall survival and cancer-specific survival rates were significantly lower in the very elderly group than in the elderly and the non-elderly groups. Congestive heart failure was negatively associated with cancer-specific survival. A significantly decreased risk for mortality was observed in all groups (p<0.001). The very elderly group had significantly higher readmission and mortality rates within 3 months of endoscopic resection than the non-elderly and elderly groups. Furthermore, the cerebrovascular disease was associated with mortality within 3 months after endoscopic resection. Conclusions Endoscopic resection for EGC can be helpful for very elderly patients, and it may play a role in achieving overall survival comparable to that of the control group.
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Affiliation(s)
- Tae Jun Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hyuk Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Chul Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yang Won Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Byung-Hoon Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jun Haeng Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Poong-Lyul Rhee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Minku Song
- Department of Digital Health, Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Samsung Medical Center, Sungkyunkwan University, Seoul, Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae J Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Jae SY, Kim HJ, Lee KH, Kunutsor SK, Heffernan KS, Choi YH, Kang M. Joint Associations of Obesity and Cardiorespiratory Fitness With Coronary Artery Calcium Composition: IS THERE EVIDENCE FOR FAT-BUT-FIT? J Cardiopulm Rehabil Prev 2022; 42:202-207. [PMID: 35135962 DOI: 10.1097/hcr.0000000000000631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION The purpose of this study was to examine the individual and joint associations of obesity and cardiorespiratory fitness (CRF) with indices of coronary artery calcification (CAC) in 2090 middle-aged men. METHODS Obesity was defined as a body mass index (BMI) ≥25 kg/m2 and a waist circumference (WC) ≥90 cm. Cardiorespiratory fitness was operationally defined as peak oxygen uptake (V˙o2peak) directly measured using gas analysis. Participants were then divided into unfit and fit categories based on age-specific V˙o2peak percentiles. Agatston scores >100 and volume and density scores >75th percentile were defined as indices of CAC, signifying advanced subclinical atherosclerosis. RESULTS Obese men had increased CAC Agatston, volume, and density scores, while higher CRF was associated with lower Agatston and volume scores after adjusting for potential confounders. In the joint analysis, unfit-obese men had higher CAC Agatston and CAC volume. The fit-obesity category was not associated with CAC Agatston (OR = 0.91: 95% CI, 0.66-1.25, for BMI and OR = 1.21: 95% CI, 0.86-1.70, for WC) and CAC volume (OR = 1.14: 95% CI, 0.85-1.53, for BMI and OR = 1.23: 95% CI, 0.90-1.69, for WC), which were similar to estimates for the fit-normal weight category. CONCLUSIONS These findings demonstrate that while obesity is positively associated with the prevalence of moderate to severe CAC scores, CRF is inversely associated with the prevalence of moderate to severe CAC scores. Additionally, the combination of being fit and obese was not associated with CAC scores, which could potentially reinforce the fat-but-fit paradigm.
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Affiliation(s)
- Sae Young Jae
- Department of Sport Science, University of Seoul, Seoul, South Korea (Drs Jae and Kim); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Mr Lee and Drs Choi and Kang); National Institute for Health Research Bristol Biomedical Research Centre, University Hospitals Bristol and Weston NHS Foundation Trust and the University of Bristol, Bristol, UK (Dr Kunutsor); Translational Health Sciences, Bristol Medical School, University of Bristol, Learning & Research Building (Level 1), Southmead Hospital, Bristol, UK (Dr Kunutsor); Department of Exercise Science, Syracuse University, Syracuse, New York (Dr Heffernan); and Division of Urban Social Health, Graduate School of Urban Public Health, University of Seoul, Seoul, South Korea (Dr Jae)
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Park D, Cho SJ, Kim K, Woo H, Kim JE, Lee JY, Koh J, Lee J, Choi JS, Chang DK, Choi YH, Chung JI, Cha WC, Jeong OS, Jekal SY, Kang M. Prediction Algorithms for Blood Pressure Based on Pulse Wave Velocity Using Health Checkup Data in Healthy Korean Men: Algorithm Development and Validation. JMIR Med Inform 2021; 9:e29212. [PMID: 34889753 PMCID: PMC8701706 DOI: 10.2196/29212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/06/2021] [Accepted: 09/24/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pulse transit time and pulse wave velocity (PWV) are related to blood pressure (BP), and there were continuous attempts to use these to predict BP through wearable devices. However, previous studies were conducted on a small scale and could not confirm the relative importance of each variable in predicting BP. OBJECTIVE This study aims to predict systolic blood pressure and diastolic blood pressure based on PWV and to evaluate the relative importance of each clinical variable used in BP prediction models. METHODS This study was conducted on 1362 healthy men older than 18 years who visited the Samsung Medical Center. The systolic blood pressure and diastolic blood pressure were estimated using the multiple linear regression method. Models were divided into two groups based on age: younger than 60 years and 60 years or older; 200 seeds were repeated in consideration of partition bias. Mean of error, absolute error, and root mean square error were used as performance metrics. RESULTS The model divided into two age groups (younger than 60 years and 60 years and older) performed better than the model without division. The performance difference between the model using only three variables (PWV, BMI, age) and the model using 17 variables was not significant. Our final model using PWV, BMI, and age met the criteria presented by the American Association for the Advancement of Medical Instrumentation. The prediction errors were within the range of about 9 to 12 mmHg that can occur with a gold standard mercury sphygmomanometer. CONCLUSIONS Dividing age based on the age of 60 years showed better BP prediction performance, and it could show good performance even if only PWV, BMI, and age variables were included. Our final model with the minimal number of variables (PWB, BMI, age) would be efficient and feasible for predicting BP.
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Affiliation(s)
- Dohyun Park
- Department of Digital Health, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea
| | - Soo Jin Cho
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Kyunga Kim
- Department of Digital Health, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea.,Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Hyunki Woo
- Data Science Team, Evidnet Inc, Gyeonggi-do, Republic of Korea
| | - Jee Eun Kim
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jin-Young Lee
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Janghyun Koh
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - JeanHyoung Lee
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jong Soo Choi
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dong Kyung Chang
- Department of Digital Health, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea.,Division of Gastroenterology, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Ji In Chung
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Won Chul Cha
- Department of Digital Health, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea.,Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Department of Emergency Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Ok Soon Jeong
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Se Yong Jekal
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Mira Kang
- Department of Digital Health, Samsung Advanced Institute of Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea.,Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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10
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Goszczynski DE, Tinetti PS, Choi YH, Hinrichs K, Ross PJ. Genome activation in equine in vitro-produced embryos. Biol Reprod 2021; 106:66-82. [PMID: 34515744 DOI: 10.1093/biolre/ioab173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/17/2021] [Accepted: 09/07/2021] [Indexed: 11/13/2022] Open
Abstract
Embryonic genome activation is a critical event in embryo development, in which the transcriptional program of the embryo is initiated. The timing and regulation of this process are species-specific. In vitro embryo production is becoming an important clinical and research tool in the horse; however, very little is known about genome activation in this species. The objective of this work was to identify the timing of genome activation, and the transcriptional networks involved, in in vitro-produced horse embryos. RNA-Seq was performed on oocytes and embryos at eight stages of development (MII, zygote, 2-cell, 4-cell, 8-cell, 16-cell, morula, blastocyst; n = 6 per stage, 2 from each of 3 mares). Transcription of seven genes was initiated at the 2-cell stage. The first substantial increase in gene expression occurred at the 4-cell stage (minor activation), followed by massive gene upregulation and downregulation at the 8-cell stage (major activation). An increase in intronic nucleotides, indicative of transcription initiation, was also observed at the 4-cell stage. Co-expression network analyses identified groups of genes that appeared to be regulated by common mechanisms. Investigation of hub genes and binding motifs enriched in the promoters of co-expressed genes implicated several transcription factors. This work represents, to the best of our knowledge, the first genomic evaluation of embryonic genome activation in horse embryos.
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Affiliation(s)
- D E Goszczynski
- Department of Animal Science, University of California, Davis, CA, USA
| | - P S Tinetti
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Y H Choi
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - K Hinrichs
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - P J Ross
- Department of Animal Science, University of California, Davis, CA, USA
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11
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Goszczynski DE, Tinetti PS, Choi YH, Ross PJ, Hinrichs K. Allele-specific expression analysis reveals conserved and unique features of preimplantation development in equine ICSI embryos. Biol Reprod 2021; 105:1416-1426. [PMID: 34515759 DOI: 10.1093/biolre/ioab174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/17/2021] [Accepted: 09/10/2021] [Indexed: 12/30/2022] Open
Abstract
Embryonic genome activation and dosage compensation are major genetic events in early development. Combined analysis of single embryo RNA-seq data and parental genome sequencing was used to evaluate parental contributions to early development and investigate X-chromosome dynamics. In addition, we evaluated dimorphism in gene expression between male and female embryos. Evaluation of parent-specific gene expression revealed a minor increase in paternal expression at the 4-cell stage that increased at the 8-cell stage. We also detected eight genes with allelic expression bias that may have an important role in early development, notably NANOGNB. The main actor in X-chromosome inactivation, XIST, was significantly upregulated at the 8-cell, morula, and blastocyst stages in female embryos, with high expression at the latter. Sexual dimorphism in gene expression was identified at all stages, with strong representation of the X-chromosome in females from the 16-cell to the blastocyst stage. Female embryos showed biparental X-chromosome expression at all stages after the 4-cell stage, demonstrating the absence of imprinted X-inactivation at the embryo level. The analysis of gene dosage showed incomplete dosage compensation (0.5 < X:A < 1) in MII oocytes and embryos up to the 4-cell stage, an increase of the X:A ratio at the 16-cell and morula stages after genome activation, and a decrease of the X:A ratio at the blastocyst stage, which might be associated with the beginning of X-chromosome inactivation. This study represents the first critical analysis of parent- and sex-specific gene expression in early equine embryos produced in vitro.
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Affiliation(s)
- D E Goszczynski
- Department of Animal Science, University of California, Davis, CA, USA
| | - P S Tinetti
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Y H Choi
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - P J Ross
- Department of Animal Science, University of California, Davis, CA, USA
| | - K Hinrichs
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
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12
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Kang D, Kim JY, Kim JY, Mun HS, Yoon SJ, Lee J, Han G, Im YH, Shin SY, Lee SK, Yu JH, Lee KH, Kim M, Park D, Choi YH, Jeong OS, Lee JH, Jekal SY, Choi JS, Guallar E, Chang Y, Ryu S, Cho J, Kang M. The Relationship Between Breast Density Change During Menopause and the Risk of Breast Cancer in Korean Women. Cancer Prev Res (Phila) 2021; 14:1119-1128. [PMID: 34507971 DOI: 10.1158/1940-6207.capr-20-0542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/14/2021] [Accepted: 08/12/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND The aim of this study was to investigate the relationship between changes in breast density during menopause and breast cancer risk. METHODS This study was a retrospective, longitudinal cohort study for women over 30 years of age who had undergone breast mammography serially at baseline and postmenopause during regular health checkups at Samsung Medical Center. None of the participants had been diagnosed with breast cancer at baseline. Mammographic breast density was measured using the American College of Radiology Breast Imaging Reporting and Data System. RESULTS During 18,615 person-years of follow-up (median follow-up 4.8 years; interquartile range 2.8-7.5 years), 45 participants were diagnosed with breast cancer. The prevalence of dense breasts was higher in those who were younger, underweight, had low parity or using contraceptives. The cumulative incidence of breast cancer increased 4 years after menopause in participants, and the consistently extremely dense group had a significantly higher cumulative incidence (CI) of breast cancer compared with other groups [CI of extremely dense vs. others (incidence rate per 100,000 person-years): 375 vs. 203, P < 0.01]. CONCLUSION Korean women whose breast density was extremely dense before menopause and who maintained this density after menopause were at two-fold greater risk of breast cancer. PREVENTION RELEVANCE Extremely dense breast density that is maintained persistently from premenopause to postmenopause increases risk of breast cancer two fold in Korean women. Therefore, women having risk factors should receive mammography frequently and if persistently extremely dense breast had been detected, additional modalities of BC screening could be considered.
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Affiliation(s)
- Danbee Kang
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea.,Center for Clinical Epidemiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ji-Yeon Kim
- Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ji-Young Kim
- Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Han Song Mun
- Health Promotion Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sook Ja Yoon
- Health Promotion Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jieun Lee
- Health Promotion Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Gayeon Han
- Center for Clinical Epidemiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young-Hyuck Im
- Division of Hematology and Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Soo-Young Shin
- Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea.,Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Se Kyung Lee
- Department of Breast Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jong-Han Yu
- Department of Breast Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyung-Hyun Lee
- Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Mincheol Kim
- Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Dohyun Park
- Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Yoon-Ho Choi
- Health Promotion Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ok Soon Jeong
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jean Hyoung Lee
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Se Yong Jekal
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jong Soo Choi
- Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Eliseo Guallar
- Department of Epidemiology and Medicine, and Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Yoosoo Chang
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea.,Department of Occupational and Environmental Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.,Center for Cohort Studies Total Healthcare Center Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea
| | - Seungho Ryu
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea.,Department of Occupational and Environmental Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.,Center for Cohort Studies Total Healthcare Center Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea
| | - Juhee Cho
- Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea. .,Center for Clinical Epidemiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Mira Kang
- Health Promotion Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. .,Digital Innovation Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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13
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Pyo JH, Kim TJ, Lee H, Choi SC, Cho SJ, Choi YH, Min YW, Min BH, Lee JH, Kang M, Lee YC, Kim JJ. Proton pump inhibitors use and the risk of fatty liver disease: A nationwide cohort study. J Gastroenterol Hepatol 2021; 36:1235-1243. [PMID: 32886822 DOI: 10.1111/jgh.15236] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 08/03/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIM Proton pump inhibitor (PPI)-induced hypochondria can change the composition of the gut microbiota, inducing overgrowth of small bowel bacteria, which has been suggested to promote the development of fatty liver disease through the gut-liver axis. In this study, we aimed to investigate the association between PPI use and the risk of fatty liver disease. METHODS A retrospective cohort study was conducted using the Korean National Health Insurance Service-National Sample Cohort, a nationwide population-based representative sample, from January 1, 2002, to December 31, 2015. PPI use was identified from treatment claims and considered as a time-varying variable. RESULTS During 1 463 556 person-years of follow-up, 75 727 patients had at least one PPI prescription, and 3735 patients developed fatty liver disease. The hazard ratio for fatty liver disease comparing PPI users with non-PPI users was 1.68 (95% confidence interval, 1.61-1.75). When adjusted for multiple confounders, including age, sex, body mass index, smoking, alcohol intake, exercise, income level, and comorbidities, the association was still significant (hazard ratio, 1.50; 95% confidence interval, 1.44-1.57). After considering the amounts of PPIs stratified by cumulative defined daily dose, the dose-response effect was observed until 180 days. Subgroup analysis also revealed that PPI use was correlated to an increased risk of fatty liver disease. CONCLUSIONS This current national wide cohort study suggests that PPI use was associated with an increased risk of fatty liver disease compared with non-use of PPIs. Clinicians should consider fatty liver as a potential risk when prescribing PPI.
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Affiliation(s)
- Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Tae Jun Kim
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Hyuk Lee
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Sung Chul Choi
- Center for Health Promotion, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Soo-Jin Cho
- Center for Health Promotion, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Yang Won Min
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Byung-Hoon Min
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Jun Haeng Lee
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Minwoong Kang
- Department of Digital Health, SAIHST, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Yeong Chan Lee
- Department of Digital Health, SAIHST, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Jae J Kim
- Department of Medicine, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea
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14
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Jung BO, Lee W, Kim J, Choi M, Shin HY, Joo M, Jung S, Choi YH, Kim MJ. Enhancement in external quantum efficiency of AlGaInP red μ-LED using chemical solution treatment process. Sci Rep 2021; 11:4535. [PMID: 33633206 PMCID: PMC7907351 DOI: 10.1038/s41598-021-83933-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/02/2021] [Indexed: 11/30/2022] Open
Abstract
To investigate the effects of their surface recovery and optical properties, extremely small sized (12 µm × 12 µm mesa area) red AlGaInP micro light emitting diodes (\documentclass[12pt]{minimal}
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\begin{document}$$\upmu$$\end{document}μ LED) were fabricated using a diluted hydrofluoric acid (HF) surface etch treatment. After the chemical treatment, the external quantum efficiencies (EQEs) of \documentclass[12pt]{minimal}
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\begin{document}$$\upmu$$\end{document}μ-LED at low and high injection current regions have been improved by 35.48% and 12.86%, respectively. The different phenomena of EQEs have a complex relationship between the suppression of non-radiative recombination originating from the etching damage of the surface and the improvement of light extraction of the sidewalls. The constant enhancement of EQE at a high injection current it is attributed to the expansion of the active region’s sidewall surface area by the selective etching of AlInP layers. The improved EQE at a low injection current is related to the minimization of the surface recombination caused by plasma damage from the surface. High-resolution transmission electron microscopy (HR-TEM) revealed physical defects on the sidewall surface, such as plasma-induced lattice disorder and impurity contamination damage, were eliminated using chemical treatment. This study suggests that chemical surface treatment using diluted HF acid can be an effective method for enhancing the \documentclass[12pt]{minimal}
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Affiliation(s)
- Byung Oh Jung
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea.
| | - Wonyong Lee
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Jeomoh Kim
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Myungshin Choi
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Hui-Youn Shin
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Minho Joo
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Sukkoo Jung
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Yoon-Ho Choi
- Materials & Devices Advanced Research Institute, LG Electronics, LG Science Park, 10, Magokjungang 10-ro, Gangseo-gu, Seoul, 07796, South Korea
| | - Moon J Kim
- Department of Materials Science and Engineering, The University of Texas at Dallas, 800 W Campbell Rd., Richardson, TX, 75080, USA
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15
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Roh YH, Yoo SJ, Choi YH, Yang HC, Nam KW. Effects of Inflammatory Disease on Clinical Progression and Treatment of Ischiogluteal Bursitis: A Retrospective Observational Study. Malays Orthop J 2021; 14:32-41. [PMID: 33403060 PMCID: PMC7752025 DOI: 10.5704/moj.2011.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Introduction: The symptoms of Ischiogluteal Bursitis (IGB) are often nonspecific and atypical, and its diagnosis is more challenging. Moreover, it is difficult to predict cases of chronic progression or poor treatment response. Therefore, the aim of this study was to investigate the clinical course of IGB patients and identify factors that are predictive of failure of conservative treatment. Materials and Methods: Our study consisted of IGB patients diagnosed between 2010 March and 2016 December who had been followed-up for at least one year. Structured questionnaires and medical records were reviewed to analyse demographic characteristics, lifestyle patterns, blood tests, and imaging studies. We categorized the cases into two groups based on the response to conservative treatment and the need for surgical intervention. Results: The most common initial chief symptoms were buttock pains in 24 patients (37.5%). Physical examinations showed the tenderness of ischial tuberosity area in 59 (92.2%) patients, but no specific findings were confirmed in 5 patients (7.8%). 51 patients (79.7%) responded well to the conservative management, 11 patients (17.2%) needed injection, and 2 patients (3.1%) had surgical treatment performed due to continuous recurrence. There was no difference in demographic and blood lab data between the two groups. However, the incidence of inflammatory diseases (response group: 10.3% vs non-response group: 66.7%, p=0.004) was significantly different between the two groups. Conclusion: The diagnosis of IGB can be missed due to variations in clinical symptoms, and cautions should be exercised in patients with inflammatory diseases as conservative treatment is less effective in them, leading to chronic progression of IGB.
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Affiliation(s)
- Y H Roh
- Department of Orthopaedics, Jeju National University Hospital, Jeju City, Republic of Korea
| | - S J Yoo
- Department of Orthopaedics, Jeju National University Hospital, Jeju City, Republic of Korea
| | - Y H Choi
- Department of Orthopaedics, Jeju National University Hospital, Jeju City, Republic of Korea
| | - H C Yang
- Department of Orthopaedics, Jeju National University Hospital, Jeju City, Republic of Korea
| | - K W Nam
- Department of Orthopaedics, Jeju National University Hospital, Jeju City, Republic of Korea
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16
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Ko D, Choi SH, Ahn S, Choi YH. Robust Indoor Localization Methods Using Random Forest-Based Filter against MAC Spoofing Attack. Sensors (Basel) 2020; 20:s20236756. [PMID: 33255976 PMCID: PMC7730504 DOI: 10.3390/s20236756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/09/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
With the development of wireless networks and mobile devices, interest on indoor localization systems (ILSs) has increased. In particular, Wi-Fi-based ILSs are widely used because of the good prediction accuracy without additional hardware. However, as the prediction accuracy decreases in environments with natural noise, some studies were conducted to remove it. So far, two representative methods, i.e., the filtering-based method and deep learning-based method, have shown a significant effect in removing natural noise. However, the prediction accuracy of these methods severely decreased under artificial noise caused by adversaries. In this paper, we introduce a new media access control (MAC) spoofing attack scenario injecting artificial noise, where the prediction accuracy of Wi-Fi-based indoor localization system significantly decreases. We also propose a new deep learning-based indoor localization method using random forest(RF)-filter to provide the good prediction accuracy under the new MAC spoofing attack scenario. From the experimental results, we show that the proposed indoor localization method provides much higher prediction accuracy than the previous methods in environments with artificial noise.
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17
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Nkenyereye L, Adhi Tama B, Shahzad MK, Choi YH. Secure and Blockchain-Based Emergency Driven Message Protocol for 5G Enabled Vehicular Edge Computing. Sensors (Basel) 2019; 20:s20010154. [PMID: 31881766 PMCID: PMC6983214 DOI: 10.3390/s20010154] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/08/2019] [Accepted: 12/23/2019] [Indexed: 11/16/2022]
Abstract
Basic safety message (BSM) are messages that contain core elements of a vehicle such as vehicle’s size, position, speed, acceleration and others. BSM are lightweight messages that can be regularly broadcast by the vehicles to enable a variety of applications. On the other hand, event-driven message (EDM) are messages generated at the time of occurrence such as accidents or roads sliding and can contain much more heavy elements including pictures, audio or videos. Security, architecture and communication solutions for BSM use cases have been largely documented on in the literature contrary to EDM due to several concerns such as the variant size of EDM, the appropriate architecture along with latency, privacy and security. In this paper, we propose a secure and blockchain based EDM protocol for 5G enabled vehicular edge computing. To offer scalability and latency for the proposed scenario, we adopt a 5G cellular architecture due to its projected features compared to 4G tong-term evaluation (LTE) for vehicular communications. We consider edge computing to provide local processing of EDM that can improve the response time of public agencies (ambulances or rescue teams) that may intervene to the scene. We make use of lightweight multi-receiver signcryption scheme without pairing that offers low time consuming operations, security, privacy and access control. EDM records need to be kept into a distributed system which can guarantee reliability and auditability of EDM. To achieve this, we construct a private blockchain based on the edge nodes to store EDM records. The performance analysis of the proposed protocol confirms its efficiency.
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Affiliation(s)
- Lewis Nkenyereye
- Department of Computer and Information Security, Sejong University, Seoul 05006, Korea;
| | - Bayu Adhi Tama
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang 37673, Korea;
| | - Muhammad K. Shahzad
- Department of Computing, National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan;
| | - Yoon-Ho Choi
- School of Computer Science and Engineering, Pusan National University, Busan 46241, Korea
- Correspondence:
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18
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Nkenyereye L, Nkenyereye L, Islam SMR, Choi YH, Bilal M, Jang JW. Software-Defined Network-Based Vehicular Networks: A Position Paper on Their Modeling and Implementation. Sensors (Basel) 2019; 19:s19173788. [PMID: 31480479 PMCID: PMC6749579 DOI: 10.3390/s19173788] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 08/29/2019] [Accepted: 08/30/2019] [Indexed: 11/16/2022]
Abstract
There is a strong devotion in the automotive industry to be part of a wider progression towards the Fifth Generation (5G) era. In-vehicle integration costs between cellular and vehicle-to-vehicle networks using Dedicated Short Range Communication could be avoided by adopting Cellular Vehicle-to-Everything (C-V2X) technology with the possibility to re-use the existing mobile network infrastructure. More and more, with the emergence of Software Defined Networks, the flexibility and the programmability of the network have not only impacted the design of new vehicular network architectures but also the implementation of V2X services in future intelligent transportation systems. In this paper, we define the concepts that help evaluate software-defined-based vehicular network systems in the literature based on their modeling and implementation schemes. We first overview the current studies available in the literature on C-V2X technology in support of V2X applications. We then present the different architectures and their underlying system models for LTE-V2X communications. We later describe the key ideas of software-defined networks and their concepts for V2X services. Lastly, we provide a comparative analysis of existing SDN-based vehicular network system grouped according to their modeling and simulation concepts. We provide a discussion and highlight vehicular ad-hoc networks' challenges handled by SDN-based vehicular networks.
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Affiliation(s)
- Lionel Nkenyereye
- Department of Computer Engineering, Dong-Eui University, Busan 614-714, Korea
| | - Lewis Nkenyereye
- Department of Computer and Information Security, Sejong University, Seoul 05006, Korea.
| | - S M Riazul Islam
- Department of Computer Science and Engineering, Sejong University, Seoul 05006, Korea
| | - Yoon-Ho Choi
- Division of Computer and Electronics Systems Engineering, Hankuk University of Foreign Studies, Yongin-si 17035, Korea
| | - Muhammad Bilal
- School of Computer Science and Engineering, Pusan National University, Busan 46241, Korea
| | - Jong-Wook Jang
- Department of Computer Engineering, Dong-Eui University, Busan 614-714, Korea.
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19
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Shin J, Ko H, Choi YH, Choi I, Song YM. Risk of comorbid cardiovascular disease in Korean long-term cancer survivors. Eur J Cancer Care (Engl) 2019; 28:e13151. [PMID: 31433537 DOI: 10.1111/ecc.13151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 03/11/2019] [Accepted: 03/25/2019] [Indexed: 12/01/2022]
Abstract
BACKGROUND Cardiovascular disease (CVD) is a common cause of death in cancer survivors. We evaluated the risk of comorbid CVD in long-term cancer survivors according to specific cancer site. METHODS Study subjects included 47,171 Koreans aged over 40 years who visited a health promotion centre between 2010 and 2012. Information on CVD and cancer was obtained from self-report. Comorbid CVD was defined as stroke, myocardial infarction or angina pectoris. The risk of comorbid CVD in survivors was compared with that in non-cancer subjects using multiple logistic regression analysis. RESULTS Among cancer survivors (n = 3,753), 330 events of CVD were reported. Age- and sex-adjusted analysis showed that odds ratio (OR) for comorbid CVD in survivors was 1.52 (95% confidence interval: 1.34-1.72) compared to non-cancer subjects (n = 43,418). After adjusting for health-related behaviour and medical history, only lung cancer survivors had 2.44 (1.01-5.89)-fold higher OR for CVD. In stratified analysis, significantly higher OR for CVD was evident in lung cancer survivors with hypertension who did not perform regular physical exercise. CONCLUSIONS Adult cancer survivors may have an increased risk of comorbid CVD that might be mediated in part by known cardiovascular risk factors depending on the specific cancer site.
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Affiliation(s)
- Jinyoung Shin
- Department of Family Medicine, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, South Korea
| | - Hyeonyoung Ko
- Department of Family Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Inyoung Choi
- Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Yun-Mi Song
- Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
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20
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Pyo JH, Lee H, Choi SC, Cho SJ, Choi YH, Min YW, Min BH, Lee JH, Yoo H, Kim K, Kim JJ. Lack of Association between Past Helicobacter pylori Infection and Diabetes: A Two-Cohort Study. Nutrients 2019; 11:nu11081874. [PMID: 31409000 PMCID: PMC6723734 DOI: 10.3390/nu11081874] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/06/2019] [Accepted: 08/09/2019] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori (H. pylori) may be involved in diabetes and other insulin-related processes. This study aimed to investigate the associations between H. pylori infection and the risks of type 2 diabetes, impaired glucose tolerance (IGT), diabetic nephropathy, and poor glycemic control. We retrospectively evaluated 16,091 subjects without diabetes at baseline who underwent repeated health examinations. Subjects were categorized according to whether they were seropositive and seronegative for H. pylori infection. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazard models. The serological results were validated using an independent cohort (n = 42,351) based on a histological diagnosis of H. pylori infection. During 108,614 person-years of follow-up, 1338 subjects (8.3%) developed newly diagnosed diabetes, although the cumulative incidence of diabetes was not significantly related to serological H. pylori status. The multivariate Cox proportional-hazards regression models revealed that H. pylori seropositivity was not significantly associated with diabetes (HR: 1.01, 95% CI: 0.88–1.16; p = 0.854), IGT (HR: 0.98, 95% CI: 0.93–1.04; p = 0.566), diabetic nephropathy (HR: 0.99, 95% CI: 0.82–1.21; p = 0.952), or poor glycemic control (HR: 1.05, 95% CI: 0.90–1.22; p = 0.535). Similarly, histopathological findings of H. pylori infection were not significantly associated with diabetes (p = 0.311), diabetic nephropathy (p = 0.888), or poor glycemic control (p = 0.989). The findings from these large Korean cohorts indicate that there does not appear to be a role for past H. pylori infection in the development of diabetes, IGT, diabetic nephropathy, or poor glycemic control.
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Affiliation(s)
- Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Hyuk Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea.
| | - Sung Chul Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Soo Jin Cho
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Yang Won Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Byung-Hoon Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Jun Haeng Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Heejin Yoo
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
| | - Jae J Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea
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21
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Moon JS, Lee SY, Kim JH, Choi YH, Yang DW, Kang JH, Ko HM, Cho JH, Koh JT, Kim WJ, Kim MS, Kim SH. Synergistic alveolar bone resorption by diabetic advanced glycation end products and mechanical forces. J Periodontol 2019; 90:1457-1469. [PMID: 31294467 DOI: 10.1002/jper.18-0453] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 01/08/2019] [Accepted: 03/01/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The association between diabetes mellitus (DM) and bone diseases is acknowledged. However, the mechanistic pathways leading to the alveolar bone (AB) destruction remain unclear. This study aims to elucidate the mechanical forces (MF)-induced AB destruction in DM and its underlying mechanism. METHODS In vivo periodontal tissue responses to MF were evaluated in rats with diabetes. In vitro human periodontal ligament (PDL) cells were either treated with advanced glycation end products (AGEs) alone or with AGEs and MF. RESULTS In vivo, the transcription of VEGF-A, colony stimulating factor-1 (CSF-1), and Ager was upregulated in diabetes, whereas changes in DDOST and Glo1 mRNAs were negligible. DM induced VEGF-A protein in the vascular cells of the PDL and subsequent angiogenesis, but DM itself did not induce osteoclastogenesis. MF-induced AB resorption was augmented in DM, and such augmentation was morphologically substantiated by the occasional undermining resorption as well as the frontal resorption of the AB by osteoclasts. The mRNA levels of CSF-1 and vascular endothelial growth factor (VEGF) during MF application were highly elevated in diabetes, compared with those of the normal counterparts. In vitro, AGEs treatment elevated Glut-1 and CSF-1 mRNA levels via the p38 and JNK pathways, whereas OGT and VEGF levels remained unchanged. Compressive MF especially caused upregulation of VEGF, CSF-1, and Glut-1 levels, and such upregulation was further enhanced by AGEs treatment. CONCLUSIONS Overloaded MF and AGEs metabolites may synergistically aggravate AB destruction by upregulating CSF-1 and VEGF. Therefore, regulating the compressive overloading of teeth, as well as the levels of diabetic AGEs, may prove to be an effective therapeutic modality for managing DM-induced AB destruction.
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Affiliation(s)
- Jung-Sun Moon
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Su-Young Lee
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jung-Ha Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Yoon-Ho Choi
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Dong-Wook Yang
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jee-Hae Kang
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Hyun-Mi Ko
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jin-Hyoung Cho
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Jeong-Tae Koh
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Won-Jae Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Min-Seok Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
| | - Sun-Hun Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, South Korea
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Choi YH, Li Y, Park D, Lee J, Michael PC, Bascuñàn J, Voccio JP, Iwasa Y, Tanaka H. A Tabletop Persistent-Mode, Liquid Helium-Free 1.5-T MgB2 "Finger" MRI Magnet: Construction and Operation of a Prototype Magnet. IEEE Trans Appl Supercond 2019; 29:4400405. [PMID: 31156321 PMCID: PMC6538265 DOI: 10.1109/tasc.2019.2900057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This paper presents results of construction and operation of a persistent-mode, liquid-helium-free, small-scale prototype magnet for the development of a tabletop 1.5-T "finger" MRI system for osteoporosis screening. The prototype magnet, composed of 2 MgB2 coils, one superconducting joint, and a persistent-current switch (PCS) built from a portion of one coil, was wound with a one continuous ~80-m long unreacted and monofilament MgB2 wire and then reacted. The test magnet was charged successfully and generated the estimated target field of 1.75 T at 5 K with the proposed PCS operation. During initial persistent-mode, the field was slightly decayed due to the index dissipation of the joint; thereafter it sustained the persistent field of 1.7 T for 35 h. The test results validated the joint resistance of < 1.2 × 10-11 as well as the proposed approach involving the PCS coil circuit model.
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Affiliation(s)
- Y H Choi
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Y Li
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - D Park
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - J Lee
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - P C Michael
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - J Bascuñàn
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - J P Voccio
- Department of Mechanical Engineering, Wentworth Institute of Technology, Boston, MA 02115
| | - Y Iwasa
- Francis Bitter Magnet Laboratory/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - H Tanaka
- Research and Development Group, Center for Technology Innovation-Energy, Hitachi Ltd., Hitachi-shi 3191221, Japan
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23
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Kim HJ, Cho MJ, Yoon ES, Choi YH, Jae SY. Association Between Cardiorespiratory Fitness And Continuous Cardiometabolic Syndrome Risk Score In Korean Men. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000562122.19636.ce] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Lee SY, Kang DY, Kim JY, Yoon SH, Choi YH, Lee W, Cho SH, Kang HR. Incidence and Risk Factors of Immediate Hypersensitivity Reactions Associated With Low-Osmolar Iodinated Contrast Media: A Longitudinal Study Based on a Real-Time Monitoring System. J Investig Allergol Clin Immunol 2019; 29:444-450. [PMID: 30676320 DOI: 10.18176/jiaci.0374] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES We investigated the incidence of immediate hypersensitivity reaction (HSR) caused by different types of low-osmolar contrast media (LOCM) and cumulative exposure to LOCM. METHODS This cohort study included all consecutive patients who underwent LOCM-enhanced computed tomography from 2012 through 2014. We assessed 5 LOCM (iobitridol, iohexol, iomeprol, iopamidol, and iopromide). All patients were monitored for adverse events, and new symptoms and signs were recorded in real time using the Contrast Safety Monitoring and Management System (CoSM2oS). RESULTS The overall incidence of immediate HSR to LOCM was 0.97% (2004 events resulting from 205 726 exposures). Incidence differed significantly depending on whether the patient had a previous history of HSR to LOCM (0.80% in patients with no history and 16.99% in patients with a positive history of HSR to LOCM, P=.001). The incidence of HSR to individual LOCM ranged from 0.72% (iohexol) to 1.34% (iomeprol), although there were no significant differences across the 5 LOCM. A longitudinal analysis demonstrated that the incidence of HSR increased gradually with more frequent previous exposure to LOCM (HR=2.006 [95%CI, 1.517-2.653], P<.001). However, this cumulative increase in risk was observed in patients who had experienced HSR to LOCM, but not in those who had not. CONCLUSION The incidence of HSR did not differ significantly across the 5 LOCM assessed in the study. Repeated exposure to LOCM did not increase the risk of HSR among patients who had never experienced HSR to LOCM.
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Affiliation(s)
- S Y Lee
- Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul, Korea.,Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - D Y Kang
- Drug Safety Monitoring Center, Seoul National University Hospital, Seoul, Korea
| | - J Y Kim
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Changwon, Korea
| | - S H Yoon
- Department of Radiology, Seoul National University College of Medicine, Seoul, Korea
| | - Y H Choi
- Department of Radiology, Seoul National University College of Medicine, Seoul, Korea
| | - W Lee
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Changwon, Korea
| | - S H Cho
- Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul, Korea.,Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.,Drug Safety Monitoring Center, Seoul National University Hospital, Seoul, Korea
| | - H R Kang
- Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul, Korea.,Division of Allergy and Clinical Immunology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.,Drug Safety Monitoring Center, Seoul National University Hospital, Seoul, Korea
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25
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Baek JH, Lee H, Myung W, Kim H, Choi YH, Kim DK, Hong KS, Choi H. The association between inflammatory markers and general psychological distress symptoms. Gen Hosp Psychiatry 2019; 56:9-12. [PMID: 30476675 DOI: 10.1016/j.genhosppsych.2018.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 11/11/2018] [Accepted: 11/15/2018] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This study explored the association between low-grade inflammation measured using multiple common inflammatory markers and general psychological distress symptoms. METHOD A total of 68,463 Korean adults were included. White blood cell counts with differential count, fibrinogen, C-reactive protein (CRP), ferritin and rheumatoid factor were measured. General psychological distress symptoms were assessed using 18 questions of psychosocial well-being index short form (PWI-SF). RESULTS Among the eight inflammatory markers measured, WBC count, segmented neutrophil count, monocyte and CRP level were significantly and independently associated with broad psychological symptoms. In contrast, fibrinogen and ferritin showed a weak association with limited number of items. No significant association was detected with lymphocyte and RF. CONCLUSION General psychological distress symptoms were associated with multiple inflammatory markers in Korean adults. The association patterns differed by the types of inflammatory markers. Additional investigation into the relationship between general inflammatory markers and diverse psychological distress symptoms is warranted.
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Affiliation(s)
- Ji Hyun Baek
- Dept. of Psychiatry, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hyewon Lee
- Dept. of Psychiatry, Seoul National University Bundang Hospital, Seongnam, Gyunggi-do, Republic of Korea; Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
| | - Woojae Myung
- Dept. of Psychiatry, Seoul National University Bundang Hospital, Seongnam, Gyunggi-do, Republic of Korea
| | - Ho Kim
- Dept. of Biostatistics and Epidemiology, Seoul National University, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Health Promotion Center, Samsung Medical Center Sungkyunkwan University School of medicine, Seoul, Republic of Korea
| | - Doh Kwan Kim
- Dept. of Psychiatry, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Kyung Sue Hong
- Dept. of Psychiatry, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hong Choi
- Dept. of Psychiatry, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Center for Health Promotion, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
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26
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Pyo JH, Lee H, Min YW, Min BH, Lee JH, Kim KM, Yoo H, Kim K, Choi YH, Kim JJ, Kim S. Effect of age on the clinical outcomes of patients with early gastric cancer with undifferentiated-type histology. Surgery 2018; 165:802-807. [PMID: 30551867 DOI: 10.1016/j.surg.2018.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/05/2018] [Accepted: 11/05/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Undifferentiated-type early gastric cancers account for a large proportion of gastric cancers in younger patients. Therefore, the clinical outcomes of endoscopic resection in younger patients are a major concern. We aimed to investigate the influence of age on lymph node metastasis and long-term survival after surgery for undifferentiated-type early gastric cancers. METHODS We identified 4,236 patients who underwent surgery for undifferentiated-type early gastric cancers. For each T stage, the correlation between age and lymph node metastasis was analyzed using a multivariate logistic regression. Lymph node metastasis rates were compared between younger (<40 years) and older patients (≥40 years) who fulfilled the expanded criteria for endoscopic resection. The Kaplan-Meier method was used to compare long-term survival between younger and older patients. RESULTS Younger age groups (20-29 and 30-39 years) had the highest lymph node metastasis rate within each T stage (5.7% and 5.7% for T1a, 26.3% and 24.1% for T1b, respectively). After adjusting for possible covariates, however, age did not have a significant effect on lymph node metastasis in either T stage (P = .127 for T1a, P = .114 for T1b). Among patients fulfilling the expanded indication for endoscopic resection, younger patients had a slightly higher lymph node metastasis rate compared with older patients (2.7% versus 2.0%), although this difference was not statistically significant. Although younger patients had a significantly better overall survival (P < .001), no significant age-related differences were observed in recurrence-free and disease-specific survival (P = .051 and P = .069) CONCLUSION: Endoscopic resection may be feasible in young patients with undifferentiated-type early gastric cancers because these patients share a similar lymph node metastasis rate and long-term survival outcomes with older patients.
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Affiliation(s)
- Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea
| | - Hyuk Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Yang Won Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Byung-Hoon Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jun Haeng Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyoung-Mee Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Heejin Yoo
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea
| | - Jae J Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Kim
- Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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27
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Park I, Choi JH, Kim EK, Kim SM, Yang JH, Song YB, Hahn JY, Choi SH, Gwon HC, Lee SH, Choi YH, Oh JK. P1790Non-invasive identification of coronary collateral vessels by coronary computed tomography. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p1790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- I Park
- International ST.Mary's Hospital, Department of Internal medicine, Division of Cardiology, Incheon, Korea Republic of
| | - J H Choi
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - E K Kim
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - S M Kim
- Samsung Medical Center, Department of Radiology, Seoul, Korea Republic of
| | - J H Yang
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - Y B Song
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - J Y Hahn
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - S H Choi
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - H C Gwon
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - S H Lee
- Samsung Medical Center, Cardiology, Seoul, Korea Republic of
| | - Y H Choi
- Samsung Medical Center, Department of Radiology, Seoul, Korea Republic of
| | - J K Oh
- Mayo Clinic, Department of Internal medicine, Rochester, United States of America
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28
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Pyo JH, Lee H, Min YW, Min BH, Lee JH, Kim KM, Yoo H, Kim K, Choi YH, Kim JJ, Kim S. Young Age and Risk of Lymph Node Metastasis in Differentiated Type Early Gastric Cancer. Ann Surg Oncol 2018; 25:2713-2719. [PMID: 30006689 DOI: 10.1245/s10434-018-6659-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Indexed: 01/23/2023]
Abstract
BACKGROUND Young patients with gastric cancer reportedly have a worse prognosis than older patients due to delayed diagnosis and more aggressive tumor behavior. However, it is unclear whether this applies to early gastric cancer (EGC), for which endoscopic resection is indicated. We investigated the association between age and lymph node metastasis (LNM). METHODS We identified 4055 patients diagnosed with EGC of differentiated histology who underwent surgery. The association between age and LNM was examined using logistic regression for each T stage separately with adjustments for multiple covariates. We compared LNM rates for each of the Japanese Endoscopic Resection Guidelines criteria in younger (< 40 years) and older patients (40 years). RESULTS The median number of lymph nodes examined was the same for T1a and T1b stages (n = 34). The median number of lymph nodes examined was not significantly different within T1a stage (P = 0.093), but within T1b stage, the number of lymph nodes examined was significantly different (P = 0.019). The highest number was between 50 and 59 years (median = 37), and the lowest number was in the 20 to 49 years and older than 70 age brackets (median = 34). LNM rate and age were not significantly associated within each stage (P values 0.269, 0.783 for T1a and T1b, respectively). Among patients fulfilling endoscopic resection criteria, the LNM rate in younger patients was lower than in older patients. CONCLUSIONS In differentiated-type EGC, young age at diagnosis was not associated with LNM rate. Therefore, endoscopic resection criteria for early gastric cancer can be applied to younger patients.
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Affiliation(s)
- Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, Seoul, Republic of Korea
| | - Hyuk Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
| | - Yang Won Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Byung-Hoon Min
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jun Haeng Lee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Kyoung-Mee Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Heejin Yoo
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Seoul, Republic of Korea
| | - Jae J Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Kim
- Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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29
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Jae SY, Laukkanen JA, Choi YH, Franklin BA. Association Between Cardiorespiratory Fitness and Indices of Coronary Artery Calcification in Men. Mayo Clin Proc 2018; 93:665-666. [PMID: 29728205 DOI: 10.1016/j.mayocp.2018.01.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 01/09/2018] [Accepted: 01/11/2018] [Indexed: 11/25/2022]
Affiliation(s)
| | | | - Yoon-Ho Choi
- Samsung Medical Center, Seoul, Republic of Korea
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Pyo JH, Ha SY, Hong SN, Chang DK, Son HJ, Kim KM, Kim H, Kim K, Kim JE, Choi YH, Kim YH. Identification of risk factors for sessile and traditional serrated adenomas of the colon by using big data analysis. J Gastroenterol Hepatol 2018; 33:1039-1046. [PMID: 29087626 DOI: 10.1111/jgh.14035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIM Little is known about the risk factors associated with serrated polyps, because the early studies, which occurred before the new World Health Organization classification was introduced, included mixtures of serrated polyps. This study aimed to evaluate the risk factors associated with the presence of sessile serrated adenomas (SSAs) and traditional serrated adenomas (TSAs) using big data analytics. METHODS Using a case-control design, we evaluated the risk factors associated with the presence of SSAs and TSAs. Subjects who underwent colonoscopies from 2002 to 2012 as part of the comprehensive health screening programs undertaken at the Samsung Medical Center, Korea, participated in this study. RESULTS Of the 48 677 individuals who underwent colonoscopies, 183 (0.4%) had SSAs and 212 (0.4%) had TSAs. The multivariate analysis determined that being aged ≥ 50 years (odds ratio [OR] 1.91, 95% confidential interval [CI] 1.27-2.90, P = 0.002) and a history of colorectal cancer among first-degree relatives (OR 3.14, 95% CI 1.57-6.27, P = 0.001) were significant risk factors associated with the presence of SSAs and that being aged ≥ 50 years (OR 2.61, 95% CI 1.79-3.80, P < 0.001), obesity (OR 1.63, 95% CI 1.12-2.36, P = 0.010), and a higher triglyceride level (OR 1.63, 95% CI 1.12-2.36, P = 0.010) were independent risk factors associated with the presence of TSAs. CONCLUSIONS We used big data analytics to determine the risk factors associated with the presence of specific polyp subgroups, and individuals who have these risk factors should be carefully scrutinized for the presence of SSAs or TSAs during screening colonoscopies.
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Affiliation(s)
- Jeung Hui Pyo
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea
| | - Sang Yun Ha
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Noh Hong
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Dong Kyung Chang
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Jung Son
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea.,Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyoung-Mee Kim
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hyeseung Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea
| | - Kyunga Kim
- Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea
| | - Jee Eun Kim
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Seoul, Korea.,Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young-Ho Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Kim MJ, Kim SS, Park KJ, An HJ, Choi YH, Lee NH, Hyun CG. Methyl jasmonate inhibits lipopolysaccharide-induced inflammatory cytokine production via mitogen-activated protein kinase and nuclear factor-κB pathways in RAW 264.7 cells. Pharmazie 2018; 71:540-543. [PMID: 29441852 DOI: 10.1691/ph.2016.6647] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
Methyl jasmonate is an important signaling molecule involved in plant defense as well as in the regulation of plant growth and development. Despite its various functions in plants, its effects on animal cells have not been widely studied and no report has been issued on the molecular aspects of its anti-inflammatory effect. In the present study, we investigated the in vitro anti-inflammatory properties of methyl jasmonate in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methyl jasmonate treatment effectively inhibited LPS-induced production of pro-inflammatory mediators (nitric oxide and prostaglandin E2) and cytokines (tumor necrosis factor-α, interleukin (IL)-1β, and IL-6) in a concentration-dependent manner. Furthermore, it attenuated the LPS-induced activation of nuclear factor-κB (NF-κB) by suppressing the degradation of the inhibitor of κB-α (IκB-α). Additionally, methyl jasmonate dose-dependently blocked the phosphorylation of mitogen-activated protein kinases (MAPKs), i.e., p38 kinase, extracellular signal-regulated kinase (ERK) 1/2, and c-Jun N-terminal kinase (JNK), in these cells. These results suggest that methyl jasmonate attenuated the LPS-induced release of pro-inflammatory mediators and cytokines by suppressing the activation of MAPK (JNK, ERK and p38) and NF-κB signaling. This study not only demonstrated that methyl jasmonate exerts anti-inflammatory activities in macrophages but also revealed its potential as a candidate for the treatment of various inflammation-associated diseases.
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Jae SY, Bunsawat K, Choi YH, Kim YS, Touyz RM, Park JB, Franklin BA. Relation of serum uric acid to an exaggerated systolic blood pressure response to exercise testing in men with normotension. J Clin Hypertens (Greenwich) 2018; 20:551-556. [DOI: 10.1111/jch.13219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/01/2017] [Accepted: 11/07/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Sae Young Jae
- Department of Sport Science; University of Seoul; Seoul South Korea
| | - Kanokwan Bunsawat
- Department of Kinesiology and Nutrition; University of Illinois at Chicago; Chicago IL USA
| | - Yoon-Ho Choi
- Center for Health Promotion; Samsung Medical Center; Sungkyunkwan University School of Medicine; Seoul South Korea
| | - Yeon Soo Kim
- Department of Physical Education; Seoul National University; Seoul South Korea
| | - Rhian M. Touyz
- Institute of Cardiovascular & Medical Sciences; University of Glasgow; Glasgow UK
| | - Jeong Bae Park
- Division of Cardiology; Cheil General Hospital; Dankook University College of Medicine; Seoul South Korea
| | - Barry A. Franklin
- Preventive Cardiology and Cardiac Rehabilitation; William Beaumont Hospital; Royal Oak MI USA
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33
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Nguyen TL, Choi YH, Aung YK, Evans CF, Trinh NH, Li S, Dite GS, Kim MS, Brennan PC, Jenkins MA, Sung J, Song YM, Hopper JL. Breast Cancer Risk Associations with Digital Mammographic Density by Pixel Brightness Threshold and Mammographic System. Radiology 2018; 286:433-442. [DOI: 10.1148/radiol.2017170306] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Tuong L Nguyen
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Yoon-Ho Choi
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Ye K Aung
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Christopher F Evans
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Nhut H Trinh
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Shuai Li
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Gillian S Dite
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Myeong-Seong Kim
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Patrick C Brennan
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Mark A Jenkins
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Joohon Sung
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - Yun-Mi Song
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
| | - John L Hopper
- From the Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, Level 3, 207 Bouverie St, Carlton, VIC 3053, Australia (T.L.N., Y.K.A., C.F.E., N.H.T., S.L., G.S.D., M.A.J., J.L.H.); Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.H.C..); Department of Radiology, National Cancer Center, Goyang-si, South Korea (M.S.K.); Faculty of Health Sciences, University of Sydney, Lidcombe, NSW, Australia (P.C.B.); Department of Epidemiology School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Korea (J.S., J.L.H.); and Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (Y.M.S.)
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Mishra A, Nam GH, Gim JA, Lee HE, Jo A, Yoon D, Oh S, Kim S, Kim A, Kim DH, Kim YC, Jeong HD, Cha HJ, Choi YH, Kim HS. Comparative evaluation of MCP gene in worldwide strains of Megalocytivirus (Iridoviridae family) for early diagnostic marker. J Fish Dis 2018; 41:105-116. [PMID: 28914452 DOI: 10.1111/jfd.12685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/18/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Members of the Iridoviridae family have been considered as aetiological agents of iridovirus diseases, causing fish mortalities and economic losses all over the world. Virus identification based on candidate gene sequencing is faster, more accurate and more reliable than other traditional phenotype methodologies. Iridoviridae viruses are covered by a protein shell (capsid) encoded by the important candidate gene, major capsid protein (MCP). In this study, we investigated the potential of the MCP gene for use in the diagnosis and identification of infections caused Megalocytivirus of the Iridoviridae family. We selected data of 66 Iridoviridae family isolates (53 strains of Megalocytivirus, eight strains of iridoviruses and five strains of Ranavirus) infecting various species of fish distributed all over the world. A total of 53 strains of Megalocytivirus were used for designing the complete primer sets for identifying the most hypervariable region of the MCP gene. Further, our in silico analysis of 102 sequences of related and unrelated viruses reconfirms that primer sets could identify strains more specifically and offers a useful and fast alternative for routine clinical laboratory testing. Our findings suggest that phenotype observation along with diagnosis using universal primer sets can help detect infection or carriers at an early stage.
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Affiliation(s)
- A Mishra
- Genetic Engineering Institute, Pusan National University, Busan, Korea
| | - G-H Nam
- Genetic Engineering Institute, Pusan National University, Busan, Korea
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, Korea
| | - J-A Gim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, Korea
| | - H-E Lee
- Genetic Engineering Institute, Pusan National University, Busan, Korea
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, Korea
| | - A Jo
- Genetic Engineering Institute, Pusan National University, Busan, Korea
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, Korea
| | - D Yoon
- Department of Chemistry, College of Natural Sciences, Pusan National University, Busan, Korea
| | - S Oh
- Department of Chemistry, College of Natural Sciences, Pusan National University, Busan, Korea
| | - S Kim
- Department of Chemistry, College of Natural Sciences, Pusan National University, Busan, Korea
| | - A Kim
- Department of Aquatic Life Medicine, Pukyong National University, Busan, Korea
| | - D-H Kim
- Department of Aquatic Life Medicine, Pukyong National University, Busan, Korea
| | - Y C Kim
- Department of Aquatic Life Medicine, Pukyong National University, Busan, Korea
| | - H D Jeong
- Department of Aquatic Life Medicine, Pukyong National University, Busan, Korea
| | - H-J Cha
- Departments of Parasitology and Genetics, College of Medicine, Kosin University, Busan, Korea
| | - Y H Choi
- Department of Biochemistry, College of Korean Medicine, Dongeui University, Busan, Korea
| | - H-S Kim
- Genetic Engineering Institute, Pusan National University, Busan, Korea
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, Korea
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Abstract
Glyphosate-surfactant is one of the most commonly used herbicides in the world. Its key component, glyphosate, is a competitive inhibitor of the shikimate pathway, a metabolic pathway found only in plants. However, severe intoxication, including lethal cases by ingestion of, glyphosate-surfactant has been reported. We describe the full recovery of two patients from glyphosate-polyoxyethyleneamine surfactant intoxication and multi-organ system failure following continuous renal replacement therapy. Both patients developed persistent shock, acute kidney injury, lactic acidosis, hyperkalaemia and multi-organ failure despite of resuscitation. We believe that continuous renal replacement therapy should be initiated immediately for removal of glyphosate-polyoxyethyleneamine surfactant in patients with signs of cardiopulmonary compromise, lactic acidosis, and renal failure. We propose the addition of glyphosate-polyoxyethyleneamine surfactant to the list of toxins for which early haemodialysis should be indicated.
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Affiliation(s)
- DH Lee
- Chung-ang University Medical Center, Department of Emergency Medicine, Seoul, Korea
| | - YH Choi
- Ewha Womans University, Department of Emergency Medicine, Ewha Womans University Medical Center, 911-1 Mokdong Yangcheon-gu, Seoul, Korea
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Yun HW, Lee DH, Lee JH, Cheon YJ, Choi YH. Serial Serum Cholinesterase Activities as a Prognostic Factor in Organophosphate Poisoned Patients. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791201900203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective Organophosphate poisoning is a serious clinical entity and of considerable morbidity and mortality. Several factors have been identified to predict outcomes of organophosphate poisoning. This investigation aims to identify the relationship between the dynamics of serum cholinesterase (SChE) activity and mortality. Methods In this retrospective study, medical records of all patients with acute organophosphate poisoning were reviewed from January 2001 to December 2009. Clinical features, SChE activity, Glasgow Coma Scale, laboratory findings, electrocardiogram finding, management and their outcomes were examined. Results A total of 169 patients were included in this study. A total of 55 patients were enrolled. Deceased patients were 8 in number. Absence of an increase in SChE activity was related with mortality in organophosphate poisoned patients (p value=0.036; odds ratio, 5.445; 95% confidence interval, 1.121-26.551). Conclusions The absence of an increase in SChE activity is associated with higher mortality in organophosphate poisoning. The SChE dynamic activity can provide a guide to physicians in the evaluation and management of organophosphate poisoned patients.
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Affiliation(s)
| | - DH Lee
- Eulji University, Department of Emergency Medicine, Seoul, South Korea
| | - JH Lee
- Eulji University, Department of Emergency Medicine, Seoul, South Korea
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Cheon YJ, Pyun WB, Lee DH, Choi YH. A Case of Electrocardiographic Change Caused by Subarachnoid Haemorrhage Mimicking Acute Myocardial Infarction. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791201900311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A 60-year-old woman was admitted to the emergency department due to syncope. The electrocardiogram (ECG) revealed normal sinus rhythm with ST segment elevation in leads I, II, and aVL. There was no stenosis or vasospasm in the coronary arteries. Transient electrocardiographic ST segment elevation which is indistinguishable from that associated with acute myocardial infarction has been reported in patients with subarachnoid hemorrhage (SAH). Until now no case was ever reported with the ECG finding with pattern of posterolateral myocardial infarction in SAH patients. So we describe a patient with SAH mimicking acute myocardial infarction.
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Affiliation(s)
| | - WB Pyun
- Ewha Womans University, Department of Cardiology, Seoul, Korea
| | - DH Lee
- Eulji University, Department of Emergency Medicine, Seoul, Korea
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Lee DH, Choi YH. A Case of Pulmonary Pneumatocoele with Splenic Laceration Caused by Vehicular Accident. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791001700512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Traumatic pneumatocoele is an uncommon complication, resulting from air trapping in an area of lung laceration, and may appear a few hours or even immediately after injury. Young adults and children are most commonly affected. Its clinical relevance lies in its rarity, which might mislead emergency physicians to perform unnecessary surgical intervention. We report a 10-year-old boy suffering from traumatic pneumatocoele with spleen laceration caused by blunt trauma. It is important for emergency physicians to be aware of this condition and of its benign course so as to avoid unnecessary operative procedures due to incorrect diagnosis.
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Affiliation(s)
- DH Lee
- Yongsan Hospital, Department of Emergency Medicine, College of Medicine, Chung-ang University, Seoul, Korea
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Affiliation(s)
- YH Choi
- Ewha Womans University, Department of Emergency Medicine, School of Medicine, Seoul, Korea
| | | | - HM Lee
- Soonchunhyang University, Department of Emergency Medicine, College of Medicine, Seoul, Korea
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Lee DH, Choi YH. A 67-Year-Old Man with Epistaxis, Melena, Gross Haematuria and Haemarthrosis. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791502200511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Superwarfarins are widely used as rodenticides. They are similar to warfarin, but they are more potent and act longer. In case of poisoning, they cause severe bleeding, usually from multiple sites. Prolonged treatment with high doses of vitamin K and/or fresh frozen plasma (FFP) transfusions may be necessary. Awareness of the problem of superwarfarin intoxication among physicians remains low and cases may go undiagnosed for days or weeks, resulting in increased morbidity and even mortality. We presented a case of delayed diagnosis of superwarfarin ingestion. The patient presented to emergency department with epistaxis, melena, and gross haematuria. He was treated with vitamin K and the International Normalised Ratio (INR) dropped from >7.0 to 1.4. The patient was discharged. However, 3 weeks later, the patient presented with haemarthrosis. Blood investigation revealed INR value >7.0 again. The patient finally received treatment with FFP and vitamin K. This case illustrates the importance to consider superwarfarin ingestion when patients presented with poisoning with coagulopathy. (Hong Kong j.emerg.med. 2015;22:324-327)
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Affiliation(s)
- DH Lee
- Chung-Ang University Department of Emergency Medicine, College of Medicine, Seoul, Korea
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Kim TJ, Kim JE, Choi YH, Hong SN, Kim YH, Chang DK, Rhee PL, Kim MJ, Jung SH, Son HJ. Obesity-related parameters and colorectal adenoma development. J Gastroenterol 2017; 52:1221-1229. [PMID: 28197803 DOI: 10.1007/s00535-017-1319-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 02/02/2017] [Indexed: 02/04/2023]
Abstract
BACKGROUND Obesity increases the risk of colorectal adenoma and colorectal cancer. However, the obesity-related parameters that are best for assessing the risk of colorectal adenoma development remain unclear. We analyzed the parameters that may best describe the association between obesity and colorectal adenoma development. METHODS In this retrospective cohort study, 3405 individuals underwent screening colonoscopy during routine health examinations. We measured body mass index; waist circumference; and metabolic parameters such as high-density lipoprotein-cholesterol, glucose, triglyceride, and systolic blood pressure. We analyzed the risk of developing colorectal adenoma, relative to obesity-related parameters, over a mean interval of 5.8 years from baseline colonoscopy. RESULTS In a multivariate analysis, waist circumference was the only obesity-related marker associated with an increased risk of metachronous colorectal adenoma. Men with waist circumferences ≥85 cm and women with waist circumference ≥82 cm had a 31% increased risk of metachronous colorectal adenoma compared to those with smaller waist circumferences [odds ratio (OR) 1.31; 95% confidence interval (CI, 1.09-1.57)]. Other factors associated with metachronous colorectal adenoma were age (OR, 1.03; 95% CI 1.02-1.04), male sex (OR 1.49; 95% CI 1.17-1.88), alcohol consumption ≥3/week (OR 1.33; 95% CI 1.10-1.62), the number of adenoma at baseline (OR 1.21; 95% CI 1.10-1.33), and the presence of advanced adenoma at baseline (OR 1.60; 95% CI 1.24-2.06). CONCLUSIONS Our findings suggest that central obesity, represented by waist circumference, is a significant predictor of metachronous colorectal adenoma, independent of body mass index and other metabolic variables.
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Affiliation(s)
- Tae Jun Kim
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jee Eun Kim
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Yoon-Ho Choi
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Noh Hong
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Young-Ho Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dong Kyung Chang
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Poong-Lyul Rhee
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Min-Ji Kim
- Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sin-Ho Jung
- Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee Jung Son
- Center for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
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Kim EJ, Kwak YG, Park SH, Kim SR, Shin MJ, Yoo HM, Han SH, Kim DW, Choi YH, Yoo JH. Trends in device utilization ratios in intensive care units over 10-year period in South Korea: device utilization ratio as a new aspect of surveillance. J Hosp Infect 2017; 100:e169-e177. [PMID: 29042233 DOI: 10.1016/j.jhin.2017.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/10/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND Device-associated infection (DAI) is an important issue related to patient safety. It is important to reduce unnecessary device utilization in order to decrease DAI rates. AIM To investigate the time trend of device utilization ratios (DURs) of voluntarily participating hospitals, collected over a 10-year period through the Korean National Healthcare-associated Infections Surveillance System (KONIS). METHODS DURs from 2006 to 2015 in 190 intensive care units (ICUs) participating in KONIS were included in this study. DURs were calculated as the ratio of device-days to patient-days. The pooled incidences of DAIs and DURs were calculated for each year of participation, and the year-wise trends were analysed. FINDINGS Year-wise ventilator utilization ratio (V-DUR) increased significantly from 0.40 to 0.41 (F = 6.27, P < 0.01), urinary catheter utilization ratio (U-DUR) increased non-significantly from 0.83 to 0.84 (F = 1.66, P = 0.10), and C-line utilization ratio (CL-DUR) decreased non-significantly from 0.55 to 0.51 (F = 1.62, P = 0.11). In the subgroup analysis, 'medical ICU' (F = 2.79, P < 0.01) and 'hospital with >900 beds' (F = 3.07, P < 0.01) were associated with the significant increase in V-DUR. CONCLUSION In Korea, V-DUR showed a significant, year-wise increasing trend. The trends for U-DUR and CL-DUR showed no significant decrease. Efforts are required to ensure the reduction of DURs.
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Affiliation(s)
- E J Kim
- Department of Infectious Diseases, Ajou University School of Medicine, Suwon, Republic of Korea
| | - Y G Kwak
- Department of Internal Medicine, Inje University Ilsan Paik Hospital, Goyang, Republic of Korea
| | - S H Park
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - S R Kim
- Infection Control Office, Korea University Guro Hospital, Seoul, Republic of Korea
| | - M J Shin
- Infection Control Office, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - H M Yoo
- Infection Control Office, Inje University Sanggye Paik Hospital, Seoul, Republic of Korea
| | - S H Han
- Department of Nursing, Soonchunhyang University College of Medicine, Cheonan, Republic of Korea
| | - D W Kim
- Department of Policy Research Affairs, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea
| | - Y H Choi
- Department of Infectious Diseases, Ajou University School of Medicine, Suwon, Republic of Korea.
| | - J H Yoo
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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Nkenyereye L, Kwon J, Choi YH. Secure and Lightweight Cloud-Assisted Video Reporting Protocol over 5G-Enabled Vehicular Networks. Sensors (Basel) 2017; 17:s17102191. [PMID: 28946633 PMCID: PMC5676728 DOI: 10.3390/s17102191] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/17/2017] [Accepted: 09/18/2017] [Indexed: 11/17/2022]
Abstract
In the vehicular networks, the real-time video reporting service is used to send the recorded videos in the vehicle to the cloud. However, when facilitating the real-time video reporting service in the vehicular networks, the usage of the fourth generation (4G) long term evolution (LTE) was proved to suffer from latency while the IEEE 802.11p standard does not offer sufficient scalability for a such congested environment. To overcome those drawbacks, the fifth-generation (5G)-enabled vehicular network is considered as a promising technology for empowering the real-time video reporting service. In this paper, we note that security and privacy related issues should also be carefully addressed to boost the early adoption of 5G-enabled vehicular networks. There exist a few research works for secure video reporting service in 5G-enabled vehicular networks. However, their usage is limited because of public key certificates and expensive pairing operations. Thus, we propose a secure and lightweight protocol for cloud-assisted video reporting service in 5G-enabled vehicular networks. Compared to the conventional public key certificates, the proposed protocol achieves entities’ authorization through anonymous credential. Also, by using lightweight security primitives instead of expensive bilinear pairing operations, the proposed protocol minimizes the computational overhead. From the evaluation results, we show that the proposed protocol takes the smaller computation and communication time for the cryptographic primitives than that of the well-known Eiza-Ni-Shi protocol.
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Affiliation(s)
- Lewis Nkenyereye
- School of Computer Science and Engineering, Pusan National University, Busan 46241, Korea.
| | - Joonho Kwon
- School of Computer Science and Engineering, Pusan National University, Busan 46241, Korea.
| | - Yoon-Ho Choi
- School of Computer Science and Engineering, Pusan National University, Busan 46241, Korea.
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Choi YH, Lim DH, Jeong JH, Park D, Jeong KS, Kim M, Song A, Chung HS, Chung KB, Yi Y, Cho MH. Characterization of Rotational Stacking Layers in Large-Area MoSe 2 Film Grown by Molecular Beam Epitaxy and Interaction with Photon. ACS Appl Mater Interfaces 2017; 9:30786-30796. [PMID: 28809109 DOI: 10.1021/acsami.7b05475] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Transition metal dichalcogenides (TMDCs) are promising next-generation materials for optoelectronic devices because, at subnanometer thicknesses, they have a transparency, flexibility, and band gap in the near-infrared to visible light range. In this study, we examined continuous, large-area MoSe2 film, grown by molecular beam epitaxy on an amorphous SiO2/Si substrate, which facilitated direct device fabrication without exfoliation. Spectroscopic measurements were implemented to verify the formation of a homogeneous MoSe2 film by performing mapping on the micrometer scale and measurements at multiple positions. The crystalline structure of the film showed hexagonal (2H) rotationally stacked layers. The local strain at the grain boundaries was mapped using a geometric phase analysis, which showed a higher strain for a 30° twist angle compared to a 13° angle. Furthermore, the photon-matter interaction for the rotational stacking structures was investigated as a function of the number of layers using spectroscopic ellipsometry. The optical band gap for the grown MoSe2 was in the near-infrared range, 1.24-1.39 eV. As the film thickness increased, the band gap energy decreased. The atomically controlled thin MoSe2 showed promise for application to nanoelectronics, photodetectors, light emitting diodes, and valleytronics.
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Affiliation(s)
- Yoon-Ho Choi
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Dong-Hyeok Lim
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Jae-Hun Jeong
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Dambi Park
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Kwang-Sik Jeong
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Minju Kim
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - AeRan Song
- Division of Physics and Semiconductor Science, Dongguk University , Seoul 100-715, Korea
| | - Hee-Suk Chung
- Analytical Research Division, Korea Basic Science Institute , Jeonju, Jeollabuk-do 54907, Korea
| | - Kwun-Bum Chung
- Division of Physics and Semiconductor Science, Dongguk University , Seoul 100-715, Korea
| | - Yeonjin Yi
- Department of Physics, Yonsei University , Seoul 120-749, Korea
| | - Mann-Ho Cho
- Department of Physics, Yonsei University , Seoul 120-749, Korea
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Jae SY, Babu AS, Yoon ES, Kurl S, Laukkanen JA, Choi YH, Franklin BA. Impact of Cardiorespiratory Fitness and Risk of Systemic Hypertension in Nonobese Versus Obese Men Who Are Metabolically Healthy or Unhealthy. Am J Cardiol 2017; 120:765-768. [PMID: 28705382 DOI: 10.1016/j.amjcard.2017.05.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/17/2017] [Accepted: 05/31/2017] [Indexed: 12/13/2022]
Abstract
Few data are available regarding the influence of body phenotype on systemic hypertension (SH) and whether cardiorespiratory fitness (CRF) attenuates this relation. We tested the hypothesis that obesity phenotypes and CRF would predict incident hypertension, evaluating 3,800 Korean men who participated in 2 health examinations in1998 to 2009. All participants were normotensive at baseline and were divided into 4 groups based on body mass index using the Asia-Pacific descriptors for obesity and metabolic health status and the National Cholesterol Education Program's adult treatment panel III (ATP-III) criteria. A metabolically healthy obese (MHO) phenotype was defined as a body mass index of ≥25 kg/m2 with <2 metabolic abnormalities. CRF was directly measured by peak oxygen uptake, and the participants were divided into unfit and fit categories based on age-specific peak oxygen uptake percentiles. Compared with the metabolically healthy nonobese phenotype, MHO and metabolically unhealthy nonobese (MUNO) phenotypes were at increased risk of SH (relative risk [RR] = 1.47; 95% confidence interval [CI], 1.07 to 2.02 and 1.62, 1.21 to 2.16) after adjusting for potential confounders. Joint analysis showed that MHO or MUNO unfit men had 1.91 and 2.27 greater risk of incident SH, respectively. However, MHO fit men had no significant RR of incident SH (RR 1.37; 95% CI, 0.93 to 2.03), whereas MUNO fit men remained at increased risk (RR 1.48; 95% CI, 1.04 to 2.11) compared with their metabolically healthy nonobese fit counterparts. In conclusion, MHO and MUNO men were at increased risk of SH, but these risks were attenuated by fitness.
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Abstract
BACKGROUND We examined whether slow heart rate recovery (HRR) after exercise testing as an estimate of impaired autonomic function is related to coronary artery calcification (CAC), an emerging marker of coronary atherosclerosis. METHODS We evaluated 2088 men who participated in a health-screening program that included measures of CAC and peak or symptom-limited cardiopulmonary exercise testing. HRR was calculated as the difference between peak heart rate (HR) during exercise testing and the HR at 2 min of recovery after peak exercise. We measured CAC using multidetector computed tomography to calculate the Agatston coronary artery calcium score. Advanced CAC was defined as a mean CAC >75th percentile for each age group. RESULTS HRR was negatively correlated with CAC (r = -.14, p < .01). After adjusting for conventional risk factors, participants in the lowest quartile of HRR (<38 bpm) were 1.59 times (95% CI: 1.17-2.18; p < .05) more likely to have advanced CAC than their counterparts in the highest quartile of HRR (>52 bpm). Each 1 bpm decrease in HRR was associated with 1% increase in advanced CAC after adjusting for potential confounders. CONCLUSIONS An attenuated HRR after exercise testing is associated with advanced CAC, independent of coronary risk factors and other related hemodynamic response. KEY MESSAGES Slow heart rate recovery (HRR) after maximal exercise testing, indicating decreased autonomic function, is associated with an increased risk of cardiovascular event and mortality. Slow HRR has been linked with the occurrence of malignant ventricular arrhythmias, but it remains unclear whether slow HRR is associated with an increased risk of coronary artery calcification (CAC), an emerging marker of coronary atherosclerosis. An attenuated HRR after exercise testing was associated with advanced CAC, independent of coronary risk factors and other potential hemodynamic confounder, supporting the hypothesis that slow HRR is related to the burden of atherosclerotic coronary artery disease.
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Affiliation(s)
- Sae Young Jae
- a Department of Sport Science , University of Seoul , Seoul , South Korea
| | - Sudhir Kurl
- b Department of Medicine , Institute of Public Health and Clinical Nutrition, University of Eastern Finland , Kuopio , Finland
| | - Jari A Laukkanen
- b Department of Medicine , Institute of Public Health and Clinical Nutrition, University of Eastern Finland , Kuopio , Finland
| | - Eun Sun Yoon
- a Department of Sport Science , University of Seoul , Seoul , South Korea
| | - Yoon-Ho Choi
- c Center for Health Promotion, Samsung Medical Center , School of Medicine, Sungkyunkwan University , Seoul , South Korea
| | - Bo Fernhall
- d Department of Kinesiology and Nutrition , University of Illinois at Chicago , Chicago , IL , USA
| | - Barry A Franklin
- e Preventive Cardiology and Cardiac Rehabilitation , William Beaumont Hospital , Royal Oak , MI , USA
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Kim TJ, Shin HY, Chang Y, Kang M, Jee J, Choi YH, Ahn HS, Ahn SH, Son HJ, Ryu S. Metabolically healthy obesity and the risk for subclinical atherosclerosis. Atherosclerosis 2017; 262:191-197. [DOI: 10.1016/j.atherosclerosis.2017.03.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 02/27/2017] [Accepted: 03/22/2017] [Indexed: 01/23/2023]
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Lee SM, Cheon JE, Choi YH, Kim IO, Kim WS, Cho HH, Lee JY, Wang KC. Limited Dorsal Myeloschisis and Congenital Dermal Sinus: Comparison of Clinical and MR Imaging Features. AJNR Am J Neuroradiol 2017; 38:176-182. [PMID: 27765739 DOI: 10.3174/ajnr.a4958] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/15/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE While limited dorsal myeloschisis is a distinctive form of spinal dysraphism, it may be confused with congenital dermal sinus. The aim of this study was to describe clinical and MR imaging findings of limited dorsal myeloschisis that can distinguish it from congenital dermal sinus. MATERIALS AND METHODS We retrospectively reviewed the clinical and MR imaging findings of 12 patients with limited dorsal myeloschisis and 10 patients with congenital dermal sinus. Skin abnormalities, neurologic deficits, and infectious complication were evaluated on the basis of clinical information. We evaluated the following MR imaging features: visibility of the tract along the intrathecal course, attachment site of the tract, level of the conus medullaris, shape of the spinal cord, and presence of intradural lesions such as dermoid/epidermoid tumors. RESULTS A crater covered with pale epithelium was the most common skin lesion in limited dorsal myeloschisis (10/12, 83%). Infectious complications were common in congenital dermal sinus (6/10, 60%), whereas none were found in limited dorsal myeloschisis (P = .003). The following MR imaging findings were significantly different between the 2 groups (P < .05): 1) higher visibility of the intrathecal tract in limited dorsal myeloschisis (10/12, 83%) versus in congenital dermal sinus (1/10, 10%), 2) the tract attached to the cord in limited dorsal myeloschisis (12/12, 100%) versus various tract attachments in congenital dermal sinus, 3) dorsal tenting of the cord in limited dorsal myeloschisis (10/12, 83%) versus in congenital dermal sinus (1/10, 10%), and 4) the presence of dermoid/epidermoid tumors in congenital dermal sinus (6/10, 60%) versus none in limited dorsal myeloschisis. CONCLUSIONS Limited dorsal myeloschisis has distinct MR imaging features: a visible intrathecal tract with dorsal tenting of the cord at the tract-cord union. Limited dorsal myeloschisis was not associated with infection and dermoid/epidermoid tumors.
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Affiliation(s)
- S M Lee
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
- Department of Radiology (S.M.L.), Kyungpook National University Medical Center, Daegu, Korea
| | - J-E Cheon
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
| | - Y H Choi
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
| | - I-O Kim
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
| | - W S Kim
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
| | - H-H Cho
- From the Departments of Radiology (S.M.L., J.-E.C., Y.H.C., I.-O.K., W.S.K., H.-H.C.)
- Department of Radiology (H.-H.C.), Ewha Womans University Mokdong Hospital, Seoul, Republic of Korea
| | - J Y Lee
- Anatomy (J.Y.L.)
- Neurosurgery, Division of Pediatric Neurosurgery (J.Y.L., K.-C.W.), Seoul National University College of Medicine, Seoul, Republic of Korea
| | - K-C Wang
- Neurosurgery, Division of Pediatric Neurosurgery (J.Y.L., K.-C.W.), Seoul National University College of Medicine, Seoul, Republic of Korea
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Kim YG, Song JB, Choi YH, Yang DG, Kim SG, Lee HG. Investigation on quench initiation and propagation characteristics of GdBCO coil co-wound with a stainless steel tape as turn-to-turn metallic insulation. Rev Sci Instrum 2016; 87:114701. [PMID: 27910603 DOI: 10.1063/1.4966676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper investigates the quench initiation and propagation characteristics of a metallic insulation (MI) coil by conducting thermal quench tests for a GdBCO single-pancake coil co-wound with a stainless steel tape as the turn-to-turn MI. The test results confirmed that the MI coil exhibited superior thermal and electrical stabilities compared to the conventional coils co-wound with organic insulation material because the operating current could flow along the radial direction due to the existence of a turn-to-turn contact when a local hot spot was generated. The results of the quench test at a heater current (Ih) of 12, 13, and 14 A indicate that the MI coil possesses a self-protecting characteristic resulting from the "current bypass" through the turn-to-turn contact. However, the test coil was not self-protecting at Ih = 15 A because the Joule heat energy generated by the radial current flow was not completely dissipated due to the characteristic resistance of the metallic insulation tape and the non-superconducting materials, including the substrate, stabilizer, and buffer layers within the high-temperature superconductor (HTS) tape. Even though the MI coil possesses superior thermal and electrical stability relative to those of conventional HTS coils co-wound with an organic material as turn-to-turn insulation, it is essential to consider the critical role of the Joule heat energy resulting from the operating current and stored magnetic energy as well as the characteristic resistances in order to further develop self-protective 2G HTS magnets.
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Affiliation(s)
- Y G Kim
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
| | - J B Song
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
| | - Y H Choi
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
| | - D G Yang
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
| | - S G Kim
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
| | - H G Lee
- Department of Materials Science and Engineering, Korea University, Anam-dong 5 ga, Seongbuk-gu, Seoul 136-713, South Korea
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Choi YH, Song JB, Yang DG, Kim YG, Hahn S, Lee HG. A novel no-insulation winding technique of high temperature-superconducting racetrack coil for rotating applications: A progress report in Korea university. Rev Sci Instrum 2016; 87:104704. [PMID: 27802736 DOI: 10.1063/1.4963680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper presents our recent progress on core technology development for a megawatt-class superconducting wind turbine generator supported by the international collaborative R&D program of the Korea Institute of Energy Technology Evaluation and Planning. To outperform the current high-temperature-superconducting (HTS) magnet technology in the wind turbine industry, a novel no-insulation winding technique was first proposed to develop the second-generation HTS racetrack coil for rotating applications. Here, we briefly report our recent studies on no-insulation (NI) winding technique for GdBCO coated conductor racetrack coils in the following areas: (1) Charging-discharging characteristics of no-insulation GdBCO racetrack coils with respect to external pressures applied to straight sections; (2) thermal and electrical stabilities of no-insulation GdBCO racetrack coils encapsulated with various impregnating materials; (3) quench behaviors of no-insulation racetrack coils wound with GdBCO conductor possessing various lamination layers; (4) electromagnetic characteristics of no-insulation GdBCO racetrack coils under time-varying field conditions. Test results confirmed that this novel NI winding technique was highly promising. It could provide development of a compact, mechanically dense, and self-protecting GdBCO magnet for use in real-world superconducting wind turbine generators.
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Affiliation(s)
- Y H Choi
- Department of Materials Science and Engineering, Korea University, Anam-Dong 5 Ga, Seongbuk-Gu, Seoul 136-713, South Korea
| | - J B Song
- Department of Materials Science and Engineering, Korea University, Anam-Dong 5 Ga, Seongbuk-Gu, Seoul 136-713, South Korea
| | - D G Yang
- Department of Materials Science and Engineering, Korea University, Anam-Dong 5 Ga, Seongbuk-Gu, Seoul 136-713, South Korea
| | - Y G Kim
- Department of Materials Science and Engineering, Korea University, Anam-Dong 5 Ga, Seongbuk-Gu, Seoul 136-713, South Korea
| | - S Hahn
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - H G Lee
- Department of Materials Science and Engineering, Korea University, Anam-Dong 5 Ga, Seongbuk-Gu, Seoul 136-713, South Korea
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