413 results on '"Ahn SK"'
Search Results
2. Abstract PD05-07: Detection of fusion transcripts among 100 breast cancer samples by next generation sequencing
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Kim, J, primary, Han, W, additional, Moon, H-G, additional, Ahn, SK, additional, In, Y-H, additional, Kim, S, additional, Lee, H-S, additional, Lee, JW, additional, Kim, JY, additional, Kim, T, additional, Kim, MK, additional, and Noh, D-Y, additional
- Published
- 2012
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3. Abstract P1-01-08: A Nomogram for predicting two or less axillary lymph node involvement for breast cancer
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Ahn, SK, primary, Kim, JS, additional, Kim, Mk, additional, Lee, JW, additional, Kim, T, additional, Kim, JY, additional, Moon, HG, additional, Han, W, additional, and Noh, D-Y, additional
- Published
- 2012
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4. P3-14-19: Impact of Chemotherapy-Induced Amenorrhea on Response to Neoadjuvant Chemotherapy in Breast Cancer.
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Ahn, SK, primary, Moon, HG, additional, Kim, JS, additional, You, JM, additional, Shin, HC, additional, Han, W, additional, and Noh, D-Y, additional
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- 2011
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5. P5-23-01: The Impact of Primary Tumor Resection on the Survival of Patients with Stage IV Breast Cancer According to Molecular Subtype.
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Ahn, SK, primary, Moon, H-G, additional, Kim, JS, additional, You, JM, additional, Shin, HC, additional, Han, W, additional, and Noh, D-Y, additional
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- 2011
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6. Abstract P4-09-15: Preoperative TPS as Valuable Prognostic Marker for Breast Cancer
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Ahn, SK, primary, Moon, HG, additional, Shin, HC, additional, Kim, HS, additional, Yom, CK, additional, Han, W, additional, and Noh, D-Y., additional
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- 2010
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7. Abstract P3-10-19: Breast Cancer Risk Prediction Model in Korean Women Using Five Polymorphisms Identified in Genome Wide Association Studies
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Han, W, primary, Woo, JH, additional, Yu, J-H, additional, Ahn, SK, additional, Kim, HS, additional, Shin, HC, additional, Yom, CK, additional, Moon, H-G, additional, and Noh, D-Y, additional
- Published
- 2010
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8. Endoscopic intranasal reduction of the orbit in isolated blowout fractures.
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Jeon S, Kwon JH, Kim JY, Ahn SK, Park JJ, Hur DG, and Seo SW
- Abstract
Conclusion. Endoscopic intranasal reduction of the orbital floor with a detachable temporary balloon, or of the medial orbital wall with a silastic sheet and Merocel(R) packing, provided good functional results and definite advantages. We suggest that these techniques are another surgical alternative for isolated orbital floor or medial wall blowout fractures that do not accompany any associated fractures of the orbital rim. Objectives. Extended applications of endoscopic sinus surgery have reported endoscopic intranasal reduction or reconstruction of the orbital wall with good functional and cosmetic results. We present our experience with endoscopic intranasal reduction of the orbit in isolated orbital floor and/or medial wall blowout fractures, treated by reduction of the orbital floor with a detachable temporary balloon, or of the medial orbital wall with a silastic sheet and Merocel packing. Subjects and Methods. Floor reduction: After creating a wide middle meatal antrostomy, herniated orbital contents and fracture-displaced floor are mobilized and reduced. The orbital floor is supported by a saline filled balloon, which is connected with an infant feeding catheter and passed through the middle meatal antrostoma. After confirming the reduction of the orbital floor by postoperative CT, the catheter is ligated and cut in short to keep it in the nasal cavity. Medial wall reduction: After completing an intranasal ethmoidectomy, herniated orbital contents and fractured lamina papyracea are mobilized and reduced. The shape of the medial orbital wall is fixed by a silastic sheet and Merocel(R) packing saturated with an antibiotic solution. Surgery was performed when the eye function could be accurately assessed, usually at 7 to 10 days following the injury. Temporary supporting of the orbital wall with a detachable temporary balloon, or a silastic sheet and Merocel(R) packing was removed 4 weeks after surgery in the out-patient clinic. Results. We have experienced 40 cases of endoscopic intranasal reduction of the orbit in blowout fractures. CT scan confirmed isolated orbital floor fracture in 11 patients, isolated medial wall fracture in 17 patients, and combined fractures of the orbital floor and the medial wall in 12 patients. Twenty five patients had diplopia, 20 patients had limitation of eye movement, and 14 patients developed enophthalmos. Thirty three of the 40 patients recovered completely without any residual eye symptoms or complications. [ABSTRACT FROM AUTHOR]
- Published
- 2007
9. Scalable CIGS Solar Cells Employing a New Device Design of Nontoxic Buffer Layer and Microgrid Electrode.
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Hwang I, Lee M, Lee A, Jeong I, Song S, Shin D, Park J, Cho A, Eo YJ, Yoo JS, Ahn SK, Gwak J, Ahn S, Seo K, and Kim K
- Abstract
The efficiency of copper indium gallium selenide (CIGS) solar cells that use transparent conductive oxide (TCO) as the top electrode decreases significantly as the device area increases owing to the poor electrical properties of TCO. Therefore, high-efficiency, large-area CIGS solar cells require the development of a novel top electrode with high transmittance and conductivity. In this study, a microgrid/TCO hybrid electrode is designed to minimize the optical and resistive losses that may occur in the top electrode of a CIGS solar cell. In addition, the buffer layer of the CIGS solar cells is changed from the conventional CdS buffer to a dry-processed wide-band gap ZnMgO (ZMO) buffer, resulting in increased device efficiency by minimizing parasitic absorption in the short-wavelength region. By optimizing the combination of ZMO buffer and the microgrid/TCO hybrid electrode, a device efficiency of up to 20.5% (with antireflection layers) is achieved over a small device area of 5 mm × 5 mm (total area). Moreover, CIGS solar cells with an increased device area of up to 20 mm × 70 mm (total area) exhibit an efficiency of up to 19.7% (with antireflection layers) when a microgrid/TCO hybrid electrode is applied. Thus, this study demonstrates the potential for high-efficiency, large-area CIGS solar cells with novel microgrid electrodes.
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- 2024
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10. Developing a PmSLP3-based vaccine formulation that provides robust long-lasting protection against hemorrhagic septicemia-causing serogroup B and E strains of Pasteurella multocida in cattle.
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Fegan JE, Waeckerlin RC, Tesfaw L, Islam EA, Deresse G, Dufera D, Assefa E, Woldemedhin W, Legesse A, Akalu M, Bayissa B, Nguyen QH, Ng D, Ahn SK, Schryvers AB, Tefera TA, Moraes TF, and Gray-Owen SD
- Subjects
- Animals, Cattle, Mice, Female, Serogroup, Pasteurella Infections prevention & control, Pasteurella Infections veterinary, Pasteurella Infections immunology, Pasteurella Infections microbiology, Adjuvants, Immunologic administration & dosage, Immunoglobulin G blood, Immunoglobulin G immunology, Mice, Inbred BALB C, Vaccination, Pasteurella multocida immunology, Hemorrhagic Septicemia prevention & control, Hemorrhagic Septicemia veterinary, Hemorrhagic Septicemia immunology, Hemorrhagic Septicemia microbiology, Bacterial Vaccines immunology, Bacterial Vaccines administration & dosage, Cattle Diseases prevention & control, Cattle Diseases immunology, Cattle Diseases microbiology, Antibodies, Bacterial blood, Antibodies, Bacterial immunology
- Abstract
Background: Pasteurella multocida is a bacterial pathogen that causes a variety of infections across diverse animal species, with one of the most devastating associated diseases being hemorrhagic septicemia. Outbreaks of hemorrhagic septicemia in cattle and buffaloes are marked by rapid progression and high mortality. These infections have particularly harmful socio-economic impacts on small holder farmers in Africa and Asia who are heavily reliant on a small number of animals kept as a means of subsistence for milk and draft power purposes. A novel vaccine target, PmSLP-3, has been identified on the surface of hemorrhagic septicemia-associated strains of P. multocida and was previously shown to elicit robust protection in cattle against lethal challenge with a serogroup B strain., Methods: Here, we further investigate the protective efficacy of this surface lipoprotein, including evaluating the immunogenicity and protection upon formulation with a variety of adjuvants in both mice and cattle., Results: PmSLP-3 formulated with Montanide ISA 61 elicited the highest level of serum and mucosal IgG, elicited long-lasting serum antibodies, and was fully protective against serogroup B challenge. Studies were then performed to identify the minimum number of doses required and the needed protein quantity to maintain protection. Duration studies were performed in cattle, demonstrating sustained serum IgG titres for 3 years after two doses of vaccine and full protection against lethal serogroup B challenge at 7 months after a single vaccine dose. Finally, a serogroup E challenge study was performed, demonstrating that PmSLP-3 vaccine can provide protection against challenge by the two serogroups responsible for hemorrhagic septicemia., Conclusion: Together, these data indicate that PmSLP-3 formulated with Montanide ISA 61 is an immunogenic and protective vaccine against hemorrhagic septicemia-causing P. multocida strains in cattle., Competing Interests: TM, AS, and SG-O are co-authors on a patent, “Slam polynucleotides and polypeptides and uses thereof” - Patent Number: WO2017136947A1. EI, JF, AS, SG-O, and TM are coauthors on a provisional patent, “Veterinary vaccines and methods for the treatment of Pasteurella multocida infections in food production animals” - United States Provisional Application No. 63/332,966 or WO/2023/201434 and PCT/CA2023/050537., (Copyright © 2024 Fegan, Waeckerlin, Tesfaw, Islam, Deresse, Dufera, Assefa, Woldemedhin, Legesse, Akalu, Bayissa, Nguyen, Ng, Ahn, Schryvers, Tefera, Moraes and Gray-Owen.)
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- 2024
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11. Temporal trends and the association between self-rated oral health and falls in community-dwelling older adults in South Korea: a secondary analysis of survey data.
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Seo HJ, Ahn SK, and Choi MJ
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- Humans, Republic of Korea epidemiology, Female, Male, Aged, Cross-Sectional Studies, Aged, 80 and over, Logistic Models, Health Surveys, Risk Factors, Accidental Falls statistics & numerical data, Oral Health trends, Independent Living, Self Report
- Abstract
Objective: This study aims to examine temporal trends and the association between falls and self-rated oral health (SROH) status in community-dwelling older Korean adults., Design: Secondary analysis of a serial cross-sectional study., Methods: We analysed biennial data from 314 846 older adults in South Korea from 2011 to 2019 using data from the Korea Community Health Survey. Self-reported fall experience data came from the injury questionnaire question, 'Have you fallen in the past year (slipping, tripping, stumbling and falling)?'. For SROH, the participants were asked, 'How do you feel about your oral health, such as teeth and gums, in your own opinion?'. The association between SROH and falls was examined using a weighted multivariable logistic regression model adjusted for sociodemographic characteristics, health status and behaviours, and psychological factors., Results: Those who reported poor SROH had a lower declining slope than the other groups, although all groups showed a significantly decreasing trend in both men and women from 2011 to 2019 (p for trend<0.001). Older adults who reported having poor SROH had a more significant history of fall accidents than the good SROH groups, controlling for potential confounding variables (adjusted OR 1.16 (95% CI 1.10 to 1.21) in men; adjusted OR 1.17 (95% CI 1.13 to 1.21) in women)., Conclusions: Older adults with poor SROH, especially women, had more fall accidents, making them a priority target for fall prevention strategies. This study suggests considering SROH status when identifying fall risk factors in community-dwelling older adults., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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12. The Factors Influencing Chronic Kidney Disease Incidence: Database from the Korean National Health Insurance Sharing Service (NHISS).
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Ko HJ, Ahn SK, Han S, Kim MJ, Na KR, Park H, and Choi DE
- Abstract
Background: The global prevalence of chronic kidney disease (CKD) is increasing, with diabetes accounting for the highest proportion. We analyzed the influence of clinical factors on the incidence of CKD according to the renal function, primary focusing on patients with diabetes. Methods: We used the Sample Cohorts Database provided by the National Health Insurance Sharing Service (NHISS) in Korea. Participants aged ≥ 40 years who underwent a health checkup in 2009 were categorized into six groups based on their eGFR values (<60 mL/min, 60-89 mL/min, ≥90 mL/min) and the presence of diabetes. And all patients with CKD at 2009 screening were excluded. The participants were tracked from 2010 to 31 December 2019. The CKD incidence rate according to the eGFR values and the effect of the accompanying factors on CKD incidence were confirmed. Results: 148,089 people without CKD were analyzed. The CKD incidence rate was highest in those with eGFR < 60 mL/min with diabetes and lowest in those with eGFR ≥ 90 mL/min without diabetes. The CKD incidence rates were similar between the eGFR < 60 mL/min group without diabetes and the eGFR 60-89 mL/min group with diabetes. Compared to under 44 years of age, the hazard ratio of CKD incidence was 8 times higher in over 75 years of age. Men had a 1.7-fold higher risk of developing CKD than women. Current smoker, hypertension, dyslipidemia, myocardial infarction history, and atrial fibrillation and flutter increased the risk of CKD incidence. Age, diabetes, and baseline eGFR are important factors in the occurrence of CKD. As age increases, the risk of developing CKD in men increases compared to women. Conclusions: These results will be helpful in predicting risk groups for CKD and establishing strategies to lowering CKD incidence.
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- 2024
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13. Application of Bifacial Semitransparent CuInSe 2 Absorber to the Bottom Cell in Bifacial Semitransparent Perovskite/CuInSe 2 Tandem Solar Cell for Albedo Environment.
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An JG, Tran H, Kim D, Lee SM, Lee A, Ahn SK, Cho JS, Gwak J, Kim T, Jeong I, and Park JH
- Abstract
Although various types of bifacial solar cells exist, few studies have been conducted on bifacial semitransparent CuInSe
2 solar cells (BS-CISe SCs) despite the attractive potential in power generation from both sides in an albedo environment. The optimized BS-CISe SCs with 300 and 800 nm-thick absorber via a streamlined single-stage co-evaporation process exhibit a power conversion efficiency (PCE) of 6.32% and 10.6%, respectively. When double-sided total 2.0 sun illumination is assumed in an albedo environment, the bifacial power generation densities (BPGD) of them increases to 9.41% and 13.9%. Four-terminal bifacial semitransparent tandem solar cells (4T-BST SCs) are fabricated to increase the BPGD by mechanically stacking a BS-perovskite (PVK) top cell on top of a BS-CISe bottom cell with the 300 and 800 nm-thick absorber layers. When summed up, the best top and bottom cell PCEs of the 4T-BST SC with 300 and 800 nm-thick BS-CISe SC are 18.8% and 21.1%, respectively. However, the practical BPGD values of the 4T-BST SC under total 2 sun illumination are interestingly 23.4% and 24.4%, respectively. This is because the BS-CISe bottom cell's thickness affects how much rear-side illumination is transmitted to the BS-PVK top cell, increasing its current density and BPGD., (© 2023 Wiley-VCH GmbH.)- Published
- 2024
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14. Increased Blood Pressure Variability Over a 16-Year Period Is Associated With Left Ventricular Diastolic Dysfunction in a Population-Based Cohort.
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Park JH, Ahn SK, Cho GY, Sung KC, Lee SK, Kim SH, and Shin C
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- Humans, Female, Adult, Middle Aged, Blood Pressure physiology, Echocardiography, Heart Rate, Diastole physiology, Ventricular Dysfunction, Left diagnostic imaging, Ventricular Dysfunction, Left epidemiology, Hypertension
- Abstract
Background: Left ventricular diastolic dysfunction (LVDD) is often associated with elevated blood pressure (BP). It is prevalent among hypertensive patients. Additionally, increased BP variability has been linked to LVDD. However, the precise connection between LVDD and BP variability within the general population remains unclear. Thus, this study aimed to evaluate this association in a general population., Methods: A total of 2,578 participants(1,311 females) with a mean age of 47.8 ± 6.7 years who had echocardiographic data from the Korean Genome and Epidemiology study with 16 years of follow-up were analyzed. LVDD was identified through the last echocardiography during the follow-up period. BP variability was assessed using mean, standard deviation (SD), and coefficient of variance (CV)., Results: LVDD was detected in 249 individuals. The cohort was divided into an LVDD group and a normal LV diastolic function group. The LVDD group had a higher percentage of females, more advanced age, higher body mass index (BMI), higher BP and BUN levels, lower heart rate, lower hemoglobin, and lower serum creatinine than the normal LV diastolic function group. Remarkably, LVDD was associated with higher BP variability. In the multivariate analysis, LVDD was associated with increased age, female sex, increased BMI, hypertension, and increased BUN. Elevated mean systolic and diastolic BPs, SD of systolic BP, mean pulse pressure (PP), SD of PP, and CV of PP were significantly linked to LVDD even after adjusting for other significant variables in the multivariate analysis., Conclusions: LVDD was identified in 249 (9.7%) participants. Increased long-term BP variability was significantly associated with LVDD in this population-based cohort., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Journal of Hypertension, Ltd. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2024
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15. Trends and regional distribution in health-related quality of life across sex and employment status: a repeated population-based cross-sectional study.
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Ahn SK, Seo HJ, and Choi MJ
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- Humans, Male, Cross-Sectional Studies, Female, Adult, Middle Aged, Republic of Korea, Sex Factors, Unemployment statistics & numerical data, Unemployment psychology, Health Surveys, Aged, Health Status, Young Adult, Prevalence, Quality of Life, Employment statistics & numerical data
- Abstract
Objectives: This study investigated the association between sex and health-related quality of life (HRQoL) based on employment status., Methods: This was a population-based cross-sectional study. Data were collected from 1 996 153 adults aged ≥19 years who participated in the Korea Community Health Survey from 2011 to 2019. Low HRQoL was classified based on separate cutoff points (males: 0.92, females: 0.90) on the European Quality of Life-5 Dimensions index. Multivariable logistic regression analyses were used to estimate odds ratios (ORs) and 95% CIs., Results: From 2011 to 2019, the trend of the prevalence of low HRQoL levels was consistently high in the order of unemployed males, unemployed females, employed males, and employed females. Regarding the regional distribution of unemployed males, the prevalence of low HRQoL was 29.5% to 43.5%. Unemployed males had a higher prevalence of low HRQoL (OR: 1.15; 95% CI: 1.12-1.24) than employed males., Conclusions: This study suggests that the prevalence of low HRQoL levels among unemployed males was consistently high at the annual trend and regional levels. Further research considering comprehensive health determinants and multidimensional public health interventions is required to prevent deterioration of HRQoL during unemployment., (© The Author(s) [2024]. Published by Oxford University Press on behalf of Journal of Occupational Health.)
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- 2024
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16. Electrostatically Powered Multimode Liquid Crystalline Elastomer Actuators.
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Saeed MH, Choi MY, Kim K, Lee JH, Kim K, Kim D, Kim SU, Kim H, Ahn SK, Lan R, and Na JH
- Abstract
Soft actuators based on liquid crystalline elastomers (LCEs) are captivating significant interest because of their unique properties combining the programmable liquid crystalline molecular order and elasticity of polymeric materials. For practical applications, the ability to perform multimodal shape changes in a single LCE actuator at a subsecond level is a bottleneck. Here, we fabricate a monodomain LCE powered by electrostatic force, which enables fast multidirectional bending, oscillation, rotation, and complex actuation with a high degree of freedom. By tuning the dielectric constant and resistivity in LCE gels, a complete cycle of oscillation and rotation only takes 0.1 s. In addition, monodomain actuators exhibit anisotropic actuation behaviors that promise a more complex deployment in a potential electromechanical system. The presented study will pave the way for electrostatically controllable isothermal manipulation for a fast and multimode soft actuator.
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- 2023
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17. Identification of an Optimized Receptor-Binding Domain Subunit Vaccine against SARS-CoV-2.
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Yu H, Worrall LJ, Berger T, Petric M, Lin BH, Vuckovic M, Robb CS, Le Q, Kenward C, Dai C, Wakeham A, Liu S, Snow B, Tobin C, Budylowski P, Guvenc F, You-Ten A, Haight J, Silvester J, Singh RP, Ahn SK, Sultana A, Poon B, Lam J, Christie-Holmes N, Ostrowski M, Gray-Owen SD, Kubli S, Mak T, Strynadka NCJ, and Brunham RC
- Subjects
- Humans, Animals, Mice, SARS-CoV-2, COVID-19 Vaccines, Aluminum Hydroxide, Spike Glycoprotein, Coronavirus, Vaccines, Subunit, Antibodies, Viral, Antibodies, Neutralizing, Mammals, COVID-19, Viral Vaccines
- Abstract
Current vaccine efforts to combat SARS-CoV-2 are focused on the whole spike protein administered as mRNA, viral vector, or protein subunit. However, the SARS-CoV-2 receptor-binding domain (RBD) is the immunodominant portion of the spike protein, accounting for 90% of serum neutralizing activity. In this study, we constructed several versions of RBD and together with aluminum hydroxide or DDA (dimethyldioctadecylammonium bromide)/TDB (d-(+)-trehalose 6,6'-dibehenate) adjuvant evaluated immunogenicity in mice. We generated human angiotensin-converting enzyme 2 knock-in mice to evaluate vaccine efficacy in vivo following viral challenge. We found that 1) subdomain (SD)1 was essential for the RBD to elicit maximal immunogenicity; 2) RBDSD1 produced in mammalian HEK cells elicited better immunogenicity than did protein produced in insect or yeast cells; 3) RBDSD1 combined with the CD4 Th1 adjuvant DDA/TDB produced higher neutralizing Ab responses and stronger CD4 T cell responses than did aluminum hydroxide; 4) addition of monomeric human Fc receptor to RBDSD1 (RBDSD1Fc) significantly enhanced immunogenicity and neutralizing Ab titers; 5) the Beta version of RBDSD1Fc provided a broad range of cross-neutralization to multiple antigenic variants of concern, including Omicron; and 6) the Beta version of RBDSD1Fc with DDA/TDB provided complete protection against virus challenge in the knock-in mouse model. Thus, we have identified an optimized RBD-based subunit vaccine suitable for clinical trials., (Copyright © 2023 by The American Association of Immunologists, Inc.)
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- 2023
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18. Comparative Analysis of Anticancer and Antibacterial Activities among Seven Trametes Species.
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Nguyen HTK, Lee J, Park Y, Park HJ, Ahn SK, Kim JK, Kang DK, Kim M, Ahn C, Kim C, and Choi J
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Species in the genus Trametes ( Basidiomycota, Polyporales ) have been used in natural medicine for a long time. Many studies reported that mycelia or fruiting bodies of Trametes spp. exhibited effects of antioxidant, anti-inflammatory, anticancer, and antimicrobial activities. However, comparative analysis in this genus is scarce due to limitation of morphological identification and the sample number. In this study, the 19 strains of seven Trametes species were chosen to generate a five-gene-based phylogeny with the 31 global references. In addition, 39 culture extracts were prepared for 13 strains to test for anticancer and antibacterial activities. Strong anticancer activities were found in several extracts from T. hirsuta and T. suaveolens . Anticancer activities of T. suaveolens , T. cf. junipericola and T. trogii were first described here. The antibacterial ability of T. versicolor and T. hirsuta extracts has been confirmed. The antibacterial activities of T. suaveolens have been reported at the first time in this study. These results suggest an efficient application of the genus Trametes as the drug resources especially for anticancer agents., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the Korean Society of Mycology.)
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- 2023
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19. Treatment Efficacy of Various Maneuvers for Lateral Canal Benign Paroxysmal Positional Vertigo With Apogeotropic Nystagmus: A Randomized Controlled Trial.
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Lee HJ, Jeon EJ, Nam S, Mun SK, Yoo SY, Bu SH, Choi JW, Chung JH, Hong SM, Lee SH, Kim MB, Koo JW, Kim HJ, Seo JH, Ahn SK, Park SN, Kim M, and Chung WH
- Abstract
Objectives: The aim of this study was to determine the most effective treatment approach by comparing the impacts of various otolith reduction techniques in patients with apogeotropic lateral semicircular canal benign paroxysmal positional vertigo (LC-BPPV)., Methods: We performed a multicenter randomized prospective study from January to December 2015, involving 72 consecutive patients with apogeotropic LC-BPPV. The patients were divided into three treatment groups: therapeutic head-shaking (group A), the Gufoni-Appiani maneuver (group B), and the cupulolith repositioning maneuver (CuRM; group C). Each group underwent evaluation and treatment up to the fourth week. Treatment success was defined as the disappearance of positional vertigo and nystagmus., Results: This study included 72 patients (49 male and 23 female), with a mean (±standard deviation) age of 55.4±13.5 years. The mean duration of vertigo experienced prior to treatment was 3.9±4.4 days. The mean latency and duration of nystagmus were 2.7±3.0 seconds and 47.9±15.8 seconds, respectively. The overall treatment frequency was 2.0±0.9. The number of treatments differed significantly among the three groups (P<0.05). After 4 weeks, the success rates for groups A, B, and C were 90.5%, 92.3%, and 100%, respectively. No significant difference was observed in the success rate across treatment., Methods: and periods (P>0.05). However, CuRM was the only method with a 100% treatment success rate., Conclusion: While no clear difference was observed among the three treatments for LC-BPPV, CuRM was found to be superior to the other approaches in the long term.
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- 2023
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20. Inhibition of GLI Transcriptional Activity and Prostate Cancer Cell Growth and Proliferation by DAX1.
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Hong SP, Kim KW, and Ahn SK
- Abstract
The Hedgehog (Hh) signaling pathway plays an essential role in the initiation and progression of prostate cancer. This is mediated by transcriptional factors belonging to the GLI (glioma-associated oncogene) family, which regulate downstream targets to drive prostate cancer progression. The activity of GLI proteins is tightly controlled by a range of mechanisms, including molecular interactions and post-translational modifications. In particular, mitogenic and oncogenic signaling pathways have been shown to regulate GLI protein activity independently of upstream Hh pathway signaling. Identifying GLI protein regulators is critical for the development of targeted therapies that can improve patient outcomes. This study aimed to identify a novel protein that directly regulates the activity of GLI transcription factors in prostate cancer. We performed gene expression, cellular analyses, and reporter assays to demonstrate that DAX1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1) interacts with GLI1 and GLI2, the master regulators of Hh signaling. Interestingly, DAX1 overexpression significantly inhibited Hh signaling by reducing GLI1 and GLI2 activity, prostate cancer cell proliferation, and viability. Our results shed light on a novel regulatory mechanism of Hh signaling in prostate cancer cells. The interaction between DAX1 and GLI transcription factors provides insight into the complex regulation of Hh signaling in prostate cancer. Given the importance of Hh signaling in prostate cancer progression, targeting DAX1-GLI interactions may represent a promising therapeutic approach against prostate cancer. Overall, this study provides new insights into the regulation of the Hh pathway and its role in prostate cancer progression. The findings suggest that DAX1 could serve as a potential therapeutic target for the treatment of prostate cancer.
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- 2023
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21. Dr. Donald S. Mattson and His Service in Gangwon Province.
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Lee SH, Lee S, Yoon JW, Koh SB, and Ahn SK
- Abstract
Competing Interests: The authors have no potential conflicts of interest to disclose.
- Published
- 2023
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22. One-Pot Synthesis of 1,3,4-Oxadiazines from Acylhydrazides and Allenoates.
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Kim SB, Maiti S, Park ES, Kim GY, Choun Y, Ahn SK, Kim JK, and Kim J
- Abstract
The framework of 1,3,4-oxadiazine is crucial for numerous bioactive molecules, but only a limited number of synthetic methods have been reported for its production. In 2015, Wang's group developed a 4-(dimethylamino)pyridine (DMAP)-catalyzed [2 + 4] cycloaddition of allenoates with N -acyldiazenes, which provided an atom-efficient route for 1,3,4-oxadiazines. However, the practicality of this method was limited by the instability of N -acyldiazenes as starting materials. Building upon our ongoing research about the aerobic oxidation of hydrazides and their synthetic applications, we hypothesized that aerobic oxidative cycloadditions using acylhydrazides instead of N -acyldiazenes may provide a more practical synthetic route for 1,3,4-oxadiazines. In this manuscript, we describe a one-pot synthetic protocol for 1,3,4-oxadiazines from acylhydrazides and allenoates. The developed one-pot protocol consists of aerobic oxidations of acylhydrazides into N -acyldiazenes using NaNO
2 and HNO3 , followed by the DMAP-catalyzed cycloaddition of allenoate with the generated N -acyldiazenes. A variety of 1,3,4-oxadiazines were produced in good to high yields. In addition, the practicality of the developed method was demonstrated by a gram-scale synthesis of 1,3,4-oxadiazine.- Published
- 2023
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23. Targeting Mitochondrial Oxidative Stress as a Strategy to Treat Aging and Age-Related Diseases.
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Lee YH, Kuk MU, So MK, Song ES, Lee H, Ahn SK, Kwon HW, Park JT, and Park SC
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Mitochondria are one of the organelles undergoing rapid alteration during the senescence process. Senescent cells show an increase in mitochondrial size, which is attributed to the accumulation of defective mitochondria, which causes mitochondrial oxidative stress. Defective mitochondria are also targets of mitochondrial oxidative stress, and the vicious cycle between defective mitochondria and mitochondrial oxidative stress contributes to the onset and development of aging and age-related diseases. Based on the findings, strategies to reduce mitochondrial oxidative stress have been suggested for the effective treatment of aging and age-related diseases. In this article, we discuss mitochondrial alterations and the consequent increase in mitochondrial oxidative stress. Then, the causal role of mitochondrial oxidative stress on aging is investigated by examining how aging and age-related diseases are exacerbated by induced stress. Furthermore, we assess the importance of targeting mitochondrial oxidative stress for the regulation of aging and suggest different therapeutic strategies to reduce mitochondrial oxidative stress. Therefore, this review will not only shed light on a new perspective on the role of mitochondrial oxidative stress in aging but also provide effective therapeutic strategies for the treatment of aging and age-related diseases through the regulation of mitochondrial oxidative stress.
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- 2023
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24. In Memory of Dr. Robert Frank Roth: Founder of Plastic Surgery in the Gangwon Province.
- Author
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Kim IY, Lee SH, Lee S, Yoon JW, Koh SB, and Ahn SK
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- 2023
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25. Reverse vaccinology-based identification of a novel surface lipoprotein that is an effective vaccine antigen against bovine infections caused by Pasteurella multocida.
- Author
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Islam EA, Fegan JE, Tefera TA, Curran DM, Waeckerlin RC, Ng D, Ahn SK, Lai CHR, Nguyen QH, Shah M, Tesfaw L, Adamu K, Medhin WW, Legesse A, Deresse G, Getachew B, Rawlyk N, Evans B, Potter A, Schryvers AB, Gray-Owen SD, and Moraes TF
- Subjects
- Cattle, Animals, Mice, Phylogeny, Vaccinology, Bacterial Vaccines, Disease Models, Animal, Immunoglobulin G, Pasteurella multocida, Hemorrhagic Septicemia microbiology, Hemorrhagic Septicemia prevention & control, Hemorrhagic Septicemia veterinary, Pasteurella Infections microbiology, Pasteurella Infections prevention & control, Pasteurella Infections veterinary
- Abstract
Pasteurella multocida can infect a multitude of wild and domesticated animals, with infections in cattle resulting in hemorrhagic septicemia (HS) or contributing to bovine respiratory disease (BRD) complex. Current cattle vaccines against P. multocida consist of inactivated bacteria, which only offer limited and serogroup specific protection. Here, we describe a newly identified surface lipoprotein, PmSLP, that is present in nearly all annotated P. multocida strains isolated from cattle. Bovine associated variants span three of the four identified phylogenetic clusters, with PmSLP-1 and PmSLP-2 being restricted to BRD associated isolates and PmSLP-3 being restricted to isolates associated with HS. Recombinantly expressed, soluble PmSLP-1 (BRD-PmSLP) and PmSLP-3 (HS-PmSLP) vaccines were both able to provide full protection in a mouse sepsis model against the matched P. multocida strain, however no cross-protection and minimal serum IgG cross-reactivity was identified. Full protection against both challenge strains was achieved with a bivalent vaccine containing both BRD-PmSLP and HS-PmSLP, with serum IgG from immunized mice being highly reactive to both variants. Year-long stability studies with lyophilized antigen stored under various temperatures show no appreciable difference in biophysical properties or loss of efficacy in the mouse challenge model. PmSLP-1 and PmSLP-3 vaccines were each evaluated for immunogenicity in two independent cattle trials involving animals of different age ranges and breeds. In all four trials, vaccination with PmSLP resulted in an increase in antigen specific serum IgG over baseline. In a blinded cattle challenge study with a recently isolated HS strain, the matched HS-PmSLP vaccine showed strong efficacy (75-87.5% survival compared to 0% in the control group). Together, these data suggest that cattle vaccines composed of PmSLP antigens can be a practical and effective solution for preventing HS and BRD related P. multocida infections., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: TFM, ABS, and SGO are co-authors on a patent, “Slam polynucleotides and polypeptides and uses thereof” - Patent Number: WO2017136947A1. EAI, JEF, ABS, SGO and TFM are co-authors on a provisional patent, “Veterinary vaccines and methods for the treatment of Pasteurella multocida infections in food production animals” - United States Provisional Application No. 63/332,966., (Copyright: © 2023 Islam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2023
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26. Hugh A. Rose (1926- ), A Missionary Pioneer and the Cornerstone of Ophthalmology at Wonju Union Christian Hospital.
- Author
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Lim SH, Lee S, Yoon JW, Koh SB, and Ahn SK
- Subjects
- Humans, History, 19th Century, Hospitals, Missionaries, Ophthalmology, Religious Missions
- Published
- 2023
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27. Engineered multi-scale roughness of carbon nanofiller-embedded 3D printed spacers for membrane distillation.
- Author
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Jeong S, Gu B, Choi S, Ahn SK, Lee J, Lee J, and Jeong S
- Subjects
- Distillation, Membranes, Artificial, Polyesters, Printing, Three-Dimensional, Graphite, Nanotubes, Carbon, Water Purification
- Abstract
Membrane distillation (MD) transfers heat and mass simultaneously through a hydrophobic membrane. Hence, it is sensitive to both concentration and temperature polarisation (CP and TP) effects. In this study, we fabricated feed spacers to improve MD efficiency by alleviating the polarisation effects. First, a 3D printed spacer design was optimised to show superior performance amongst the others tested. Then, to further enhance spacer performance, we incorporated highly thermally stable carbon nanofillers, including carbon nanotubes (CNT) and graphene, in the fabrication of filaments for 3D printing. All the fabricated spacers had a degree of engineered multi-scale roughness, which was relatively high compared to that of the polylactic acid (PLA) spacer (control). The use of nanomaterial-incorporated spacers increased the mean permeate flux significantly compared to the PLA spacer (27.1 L/m
2 h (LMH)): a 43% and 75% increase when using the 1% graphene-incorporated spacer (38.9 LMH) and 2% CNT incorporated spacer (47.5 LMH), respectively. This could be attributed to the locally enhanced turbulence owing to the multi-scale roughness formed on the spacer, which further increased the vaporisation rate through the membrane. Interestingly, only the CNT-embedded spacer markedly reduced the ion permeation through the membrane, which may be due to the effective reduction of CP. This further decreased with increasing CNT concentration, confirming that the CNT spacer can simultaneously reduce the CP and TP effects in the MD process. Finally, we successfully proved that the multi-scale roughness of the spacer surface induces micromixing near the membrane walls, which can improve the MD performance via computational fluid dynamics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
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28. Non-linear relationship between body mass index and self-rated health in older Korean adults: body image and sex considerations.
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Yoon SJ, Jung JG, Ahn SK, Kim JS, and Hong JH
- Subjects
- Male, Humans, Female, Aged, Body Mass Index, Overweight, Republic of Korea epidemiology, Body Image, Health Status
- Abstract
Objectives: The purpose of this study was to investigate the association between body mass index (BMI) and self-rated health (SRH) in older adults aged over 65 years while examining the influence of self-perceived body image (SBI) and sex., Methods: Raw data were obtained from the Korea Community Health Survey, which included BMI measurements of Koreans aged over 65 years (n=59,628). Non-linear relationships between BMI and SRH were analyzed separately for each sex using restricted cubic splines while controlling for SBI and other confounding variables., Results: Men showed a reverse J-shaped association, while women showed a J-shaped association between BMI and poor SRH. However, including SBI in the model changed this association for men to an inverted U-shape showing a negative direction, with the highest risk of poor SRH observed in the underweight to overweight range. For women, a nearly linear positive relationship was observed. Regardless of BMI, those who perceived their weight as not "exactly the right weight" had a higher risk of poor SRH than those who perceived their weight as "exactly the right weight" in both men and women. Older men who thought they were much too fat or too thin had similar highest risks of poor SRH, whereas older women who thought they were too thin had the highest risk of poor SRH., Conclusions: The findings of this study emphasize the importance of considering sex and body image perceptions when assessing the relationship between BMI and SRH in older adults, especially in men.
- Published
- 2023
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29. ROS- and pH-Responsive Polydopamine Functionalized Ti 3 C 2 T x MXene-Based Nanoparticles as Drug Delivery Nanocarriers with High Antibacterial Activity.
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Zhang WJ, Li S, Vijayan V, Lee JS, Park SS, Cui X, Chung I, Lee J, Ahn SK, Kim JR, Park IK, and Ha CS
- Abstract
Premature drug release and poor controllability is a challenge in the practical application of tumor therapy, which may lead to poor chemotherapy efficacy and severe adverse effects. In this study, a reactive oxygen species (ROS)-cleavable nanoparticle system (MXene-TK-DOX@PDA) was designed for effective chemotherapy drug delivery and antibacterial applications. Doxorubicin (DOX) was conjugated to the surface of (3-aminopropyl)triethoxysilane (APTES)-functionalized MXene via an ROS-cleavable diacetoxyl thioketal (TK) linkage. Subsequently, the surfaces of the MXene nanosheets were coated with pH-responsive polydopamine (PDA) as a gatekeeper. PDA endowed the MXene-TK-DOX@PDA nanoparticles with superior biocompatibility and stability. The MXene-TK-DOX@PDA nanoparticles had an ultrathin planar structure and a small lateral size of approximately 180 nm. The as-synthesized nanoparticles demonstrated outstanding photothermal conversion efficiency, superior photothermal stability, and a remarkable extinction coefficient (23.3 L g
-1 cm-1 at 808 nm). DOX exhibited both efficient ROS-responsive and pH-responsive release performance from MXene-TK-DOX@PDA nanoparticles due to the cleavage of the thioketal linker. In addition, MXene-TK-DOX@PDA nanoparticles displayed high antibacterial activity against both Gram-negative Escherichia coli ( E. coli ) and Gram-positive Bacillus subtilis ( B. subtilis ) within 5 h. Taken together, we hope that MXene-TK-DOX@PDA nanoparticles will enrich the drug delivery system and significantly expand their applications in the biomedical field.- Published
- 2022
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30. Atom-Scale Chemistry in Chalcopyrite-Based Photovoltaic Materials Visualized by Atom Probe Tomography.
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Kim K, Jung C, Yim K, Jeong I, Shin D, Hwang I, Song S, Ahn SK, Eo YJ, Cho A, Cho JS, Park JH, Choi PP, Yun JH, and Gwak J
- Abstract
Chalcopyrite-based materials for photovoltaic devices tend to exhibit complex structural imperfections originating from their polycrystalline nature; nevertheless, properly controlled devices are surprisingly irrelevant to them in terms of resulting device performances. The present work uses atom probe tomography to characterize co-evaporated high-quality Cu(In,Ga)Se
2 (CIGS) films on flexible polyimide substrates either with or without doping with Na or doping with Na followed by K via a post-deposition treatment. The intent is to elucidate the unique characteristics of the grain boundaries (GBs) in CIGS, in particular the correlations/anti-correlations between matrix elements and the alkali dopants. Various compositional fluctuations are identified at GBs irrespective of the presence of alkali elements. However, [Cu-poor and Se/In,Ga-rich] GBs are significantly more common than [Cu-rich and Se/In,Ga-poor] ones. In addition, the anti-correlations between Cu and the other matrix elements are found to show not only regular trends among themselves but also the association with the degree of alkali segregation at GBs. The Na and K concentrations exhibited a correlation at the GBs but not in the intragrain regions. Density functional theory calculations are used to explain the compositional fluctuations and alkali segregation at the GBs. Our experimental and theoretical findings not only reveal the benign or beneficial characteristics of the GBs of CIGS but also provide a fundamental understanding of the GB chemistry in CIGS-based materials.- Published
- 2022
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31. Dual (pH- and ROS-) Responsive Antibacterial MXene-Based Nanocarrier for Drug Delivery.
- Author
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Zhang WJ, Li S, Yan YZ, Park SS, Mohan A, Chung I, Ahn SK, Kim JR, and Ha CS
- Subjects
- Doxorubicin pharmacology, Doxorubicin chemistry, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Drug Liberation, Spectroscopy, Fourier Transform Infrared, Hydrogen-Ion Concentration, Escherichia coli, Drug Delivery Systems
- Abstract
In this study, a novel MXene (Ti
3 C2 Tx )-based nanocarrier was developed for drug delivery. MXene nanosheets were functionalized with 3, 3'-diselanediyldipropionic acid (DSeDPA), followed by grafting doxorubicin (DOX) as a model drug to the surface of functionalized MXene nanosheets (MXene-Se-DOX). The nanosheets were characterized using scanning electron microscopy, atomic force microscopy (AFM), transmission electron microscopy, energy-dispersive X-ray spectroscopy (EDX), nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and zeta potential techniques. The drug-loading capacity (17.95%) and encapsulation efficiency (41.66%) were determined using ultraviolet-visible spectroscopy. The lateral size and thickness of the MXene nanosheets measured using AFM were 200 nm and 1.5 nm, respectively. The drug release behavior of the MXene-Se-DOX nanosheets was evaluated under different medium conditions, and the nanosheets demonstrated outstanding dual (reactive oxygen species (ROS)- and pH-) responsive properties. Furthermore, the MXene-Se-DOX nanosheets exhibited excellent antibacterial activity against both Gram-negative E. coli and Gram-positive B. subtilis .- Published
- 2022
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32. Human-muscle-inspired single fibre actuator with reversible percolation.
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Kim IH, Choi S, Lee J, Jung J, Yeo J, Kim JT, Ryu S, Ahn SK, Kang J, Poulin P, and Kim SO
- Subjects
- Animals, Humans, Mammals, Graphite chemistry, Robotics
- Abstract
Artificial muscles are indispensable components for next-generation robotics capable of mimicking sophisticated movements of living systems. However, an optimal combination of actuation parameters, including strain, stress, energy density and high mechanical strength, is required for their practical applications. Here we report mammalian-skeletal-muscle-inspired single fibres and bundles with large and strong contractive actuation. The use of exfoliated graphene fillers within a uniaxial liquid crystalline matrix enables photothermal actuation with large work capacity and rapid response. Moreover, the reversible percolation of graphene fillers induced by the thermodynamic conformational transition of mesoscale structures can be in situ monitored by electrical switching. Such a dynamic percolation behaviour effectively strengthens the mechanical properties of the actuator fibres, particularly in the contracted actuation state, enabling mammalian-muscle-like reliable reversible actuation. Taking advantage of a mechanically compliant fibre structure, smart actuators are readily integrated into strong bundles as well as high-power soft robotics with light-driven remote control., (© 2022. The Author(s).)
- Published
- 2022
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33. A Novel Diamine Containing Ester and Diphenylethane Groups for Colorless Polyimide with a Low Dielectric Constant and Low Water Absorption.
- Author
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Lee JS, Yan YZ, Park SS, Ahn SK, and Ha CS
- Abstract
In this study, a novel diamine monomer containing ester and phenyl moieties, 1,2-diphenylethane-1,2-diyl bis(4-aminobenzoate) (1,2-DPEDBA), was synthesized through a three-step reaction. Using this diamine, a novel polyimide (PI) film was prepared with 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6-FDA) as a counter dianhydride through a typical two-step chemical imidization. For comparison, poly(pyromellitic dianhydride-co-4,4'-oxydianiline) (PMDA-ODA PI) was also synthesized via thermal imidization. The resulting 6-FDA-DPEDBA PI film was not only soluble in common polar solvents with high boiling points, such as N,N-dimethylacetamide (DMAc) and N,N-dimethylformamide (DMF), but also soluble in common low-boiling-point polar solvents, such as chloroform (CHCl
3 ) and dichloromethane (CH2 Cl2 ), at room temperature. The resulting novel PI showed a 5% weight loss temperature (T5 d ) at 360 °C under a nitrogen atmosphere. The resulting PI film was colorless and transparent with a transmittance of 87.1% in the visible light region ranging from 400 to 760 nm. The water absorption of the novel PI film was of 1.78%. The PI film also possessed a good moisture barrier and hydrophobicity. Furthermore, the resulting PI film displayed a low dielectric constant of 2.17 at 106 Hz at room temperature. In conclusion, the novel PI film exhibited much better optical transparency, lower moisture absorption, and a lower dielectric constant as well as better solubility than the PMDA-ODA PI film, which is insoluble in any solvent, although its thermal stability is not better than that of PMDA-ODA PI.- Published
- 2022
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34. Does the morphology of the umbilicus influence the incidence of surgical site infections in transumbilical single-incision laparoscopic appendectomy?
- Author
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Lee DJ, Kim KY, Ahn SK, Yoon SN, Cho JW, Lee SY, Jung BH, Kim BC, and Hwang JW
- Abstract
Background: Transumbilical laparoscopic appendectomy (TULA) may be a feasible alternative to conventional laparoscopic appendectomy. However, a transumbilical incision may increase incisional surgical site infections (SSIs) compared to conventional laparoscopic appendectomy. This study aimed to investigate the relationship between the morphology of the umbilicus and the incidence of SSIs in patients who underwent TULA., Patients and Methods: This retrospective study analysed the medical records of consecutive patients who underwent surgery for acute appendicitis at our institution from June 2016 to October 2020. The patients were assigned to the SSI group (those with an SSI) or the non-SSI group. The morphology of the umbilicus was calculated by measuring its width and depth on preoperative computed tomography images and was compared between the SSI and non-SSI groups., Results: The SSI group included 23 patients, while the non-SSI group included 252 patients. The width of the umbilicus was significantly shorter in the SSI group than in the non-SSI group (29 ± 10 mm vs. 34 ± 9 mm, P = 0.027). The umbilicus was slightly deeper in the SSI group than in the non-SSI group; however, the difference was not significant (16 mm vs. 15 mm, P = 0.384)., Conclusions: This was the first study investigating the correlation between the morphology of the umbilicus and SSI development in TULA. SSIs tended to occur more commonly in a narrow and deep umbilicus. An extension of the umbilical incision may help prevent SSI in patients with this umbilical morphology., Competing Interests: None
- Published
- 2022
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35. Correction to: Psychological Impact of Type of Breast Cancer Surgery: A National Cohort Study.
- Author
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Ahn SK, Oh S, Kim J, Choi JS, and Hwang KT
- Published
- 2022
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36. Psychological Impact of Type of Breast Cancer Surgery: A National Cohort Study.
- Author
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Ahn SK, Oh S, Kim J, Choi JS, and Hwang KT
- Subjects
- Axilla pathology, Cohort Studies, Female, Humans, Lymph Node Excision, Lymphatic Metastasis, Mastectomy, Sentinel Lymph Node Biopsy, Breast Neoplasms pathology, Breast Neoplasms surgery, Sleep Initiation and Maintenance Disorders surgery
- Abstract
Background: The present study assessed the impact of different types of breast surgery on rates of psychological disorders in breast cancer patients., Methods: This nationwide cohort study, based on Korean Health Insurance Review and Assessment Service claims data, included 26,259 breast patients who underwent surgery from June 1, 2017, to December 31, 2018. Associations between the incidence of psychological disorders and variables were evaluated by time dependent Cox regression analyses., Results: Of the 26,259 patients, 9394 (35.8%) underwent total mastectomy (TM) and 16,865 (64.2%) underwent partial mastectomy (PM); of the former, 4056 (43.2%) underwent breast reconstruction surgery (RS). A total of 4685 patients (17.84%) were newly diagnosed with psychological disorders after surgery. Multivariable analysis showed that axillary lymph node dissection was significantly associated with increased rates of overall psychological disorders (p < 0.0001), depression (p = 0.0462), anxiety (p < 0.0001) and insomnia (p < 0.0001). The rates of overall psychological disorders (p = 0.0002) and insomnia (p = 0.01) were significantly lower in patients who underwent TM than PM. RS tended to associated with reduced rates of overall psychological disorders in patients who underwent TM. Subgroup analysis showed that, compared with PM, RS after TM significantly associated with a reduced incidence of overall psychological disorders and insomnia in younger patients (< 50 years) and those who underwent sentinel lymph node biopsy., Conclusion: In contrast to general belief, rates of overall psychological disorders and insomnia were lower in patients who underwent TM than PM. Moreover, RS after TM confers psychological benefit in younger patients with early stage breast cancer compared with PM., (© 2022. The Author(s).)
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- 2022
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37. Adsorption mechanisms on perfluorooctanoic acid by FeCl 3 modified granular activated carbon in aqueous solutions.
- Author
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Ahn SK, Park KY, Song WJ, Park YM, and Kweon JH
- Subjects
- Adsorption, Caprylates, Fluorocarbons, Humans, Kinetics, Water, Charcoal chemistry, Water Pollutants, Chemical analysis
- Abstract
Perfluorooctanoic acid (PFOA) is an emerging organic pollutant that is persistent in the environmental, and has been detected in humans, and wildlife. Several technologies, such as activated carbon (AC) adsorption have been used to remove PFOA from water. In this study, Fe-impregnation with/without post-thermal treatment of AC was applied to improve the adsorption of PFOA. The adsorption mechanisms were evaluated using three kinetic models: pseudo-first-order model, pseudo-second-order model, and intra-particle diffusion models. Interpretation of experimental results with the kinetic models revealed that chemical interactions, such as electrostatic attraction or complexation were suggested as the adsorption mechanisms along with physical adsorption. Two isotherm models demonstrated that the modified ACs (171.0-189.9 mg g
-1 ) had increases in adsorption capacities than the unmodified AC (164.9 mg g-1 ), which indicated that modification improved the maximum achievable surface concentrations and adsorption affinity to some extent. The evenly distributed iron content on the modified ACs was visualized using an energy dispersive X-ray spectroscopy. The Fe-impregnated AC showed a reduction in the specific surface area and total pore volume; however, post-thermal treatment largely recovered the pore structures. The isotherms normalized by the accessible surface area revealed the importance of the Fe-impregnated surfaces on PFOA adsorption. Comparable pH values of the point of zero charge and chemical compositions of the ACs implied that an increase in Fe-impregnated surface was crucial to improve PFOA adsorption. Thus, substantial enhancement of PFOA removal can be achieved by implementing a proper strategy for AC modification, especially using Fe-impregnation., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
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38. An Evaluation of a New Quantitative Point-of Care Diagnostic to Measure Glucose-6-phosphate Dehydrogenase Activity.
- Author
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Bahk YY, Ahn SK, Jeon HJ, Na BK, Lee SK, and Shin HJ
- Subjects
- Glucosephosphate Dehydrogenase therapeutic use, Humans, Point-of-Care Systems, Primaquine, Reagent Kits, Diagnostic, Antimalarials therapeutic use, Glucosephosphate Dehydrogenase Deficiency diagnosis, Glucosephosphate Dehydrogenase Deficiency epidemiology, Malaria epidemiology, Malaria, Vivax epidemiology
- Abstract
Malaria continues to be one of the most crucial infectious burdens in endemic areas worldwide, as well as for travelers visiting malaria transmission regions. It has been reported that 8-aminoquinolines are effective against the Plasmodium species, particularly primaquine, for anti-hypnozoite therapy in P. vivax malaria. However, primaquine causes acute hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Therefore, G6PD deficiency testing should precede hypnozoite elimination with 8-aminoquinoline. Several point-of-care devices have been developed to detect G6PD deficiency. The aim of the present study was to evaluate the performance of a novel, quantitative G6PD diagnostics based on a metagenomic blue fluorescent protein (mBFP). We comparatively evaluated the sensitivity and specificity of the G6PD diagnostic modality with standard methods using 120 human whole blood samples. The G6PD deficiency was spectrophotometrically confirmed. The performance of the G6PD quantitative test kit was compared with that of a licensed control medical device, the G6PD strip. The G6PD quantitative test kit had a sensitivity of 95% (95% confidence interval (CI): 89.3-100%) and a specificity of 100% (95% CI: 94.3-100%). This study shows that the novel diagnostic G6PD quantitative test kit could be a cost-effective and time-efficient, and universally mandated screening tool for G6PD deficiency.
- Published
- 2022
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39. Slidable Cross-Linking Effect on Liquid Crystal Elastomers: Enhancement of Toughness, Shape-Memory, and Self-Healing Properties.
- Author
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Choi S, Kim B, Park S, Seo JH, and Ahn SK
- Abstract
The network structures of liquid crystal elastomers (LCEs) are crucial to impart rubbery behavior to LCEs and enable reversible actuation. Most LCEs developed to date are covalently linked, implying that the cross-links are fixed at a particular position. Herein, we report a new class of LCEs integrating polyrotaxanes (PRs) as slidable cross-links (PR-LCEs). Interestingly, the incorporation of a low loading (0.3-2.0 wt %) of the PR cross-linkers to the LCE causes a significant impact on various properties of the resulting PR-LCEs due to the pulley effect. The optimum PR loading is determined to be 0.5 wt %, at which point the toughness and damping behavior are maximized. The robust mechanical properties of the PR-LCE offers a superior actuation performance to that of the pristine LCE along with an excellent quadruple shape-memory effect. Furthermore, the incorporation of PR is useful to enhance the efficiency of shape-memory-assisted self-healing when heating above the nematic-isotropic transition.
- Published
- 2022
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40. Remote-controllable and encryptable smart glasses: a photoresponsive azobenzene molecular commander determines the molecular alignments of liquid crystal soldiers.
- Author
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Rim M, Kang DG, Jung D, Lim SI, Lee KM, Godman NP, McConney ME, De Sio L, Ahn SK, and Jeong KU
- Abstract
For the development of optically encryptable smart glass that can control the molecular alignment of liquid crystals (LCs), an azobenzene-based reactive molecule (ARM) capable of trans-cis photoisomerization is newly designed and synthesized. Photo-triggered LC-commandable smart glasses are successfully constructed by the surface functionalization technique using 3-aminopropyltriethoxysilane (APTMS) coupling agent and an ARM. The surface functionalization with the ARM is verified by spectroscopic analysis and various observations including changes in the wettability and surface morphology. Using the ARM-treated substrate, the LC command cell which can effectively switch the molecular orientation of nematic LC (E7) by the irradiation of UV and visible light is demonstrated. The results of optical investigation demonstrate the directional correlation between light and photoisomerization, revealing the tilt mechanism of azobenzene units. The capability to control the molecular orientation of LCs remotely and selectively allows the development of remote-controllable and encryptable smart glasses.
- Published
- 2022
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41. Practical Enhancements in Current Density and Power Generation of Bifacial Semitransparent Ultrathin CIGSe Solar Cells via Utilization of Wide Bandgap Zn-Based Buffer.
- Author
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Kim D, Shin SS, Jo Y, Lee SM, Ahn SK, Cho JS, Yun JH, Lee HS, and Park JH
- Abstract
Among many building-integrated semitransparent photovoltaics (BISTPVs), semitransparent ultrathin (STUT) Cu(In
x ,Ga1-x )Se2 (CIGSe) solar cells are distinguishable due to their potential high power conversion efficiency (PCE) among other thin-film solar cells, versatile applicability based on thin film deposition processes, high stability consisting of all inorganic compositions, and practical expandability to bifacial applications. However, the fundamental trade-off relationship between PCE and transparency limits the performance of BISTPV because implementing a higher semitransparency lowers the optical budget of incoming light. To expand the available optical budget and to enhance the PCE while maintaining a suitable transparency in STUT CIGSe solar cell with single-stage coevaporated 500-nm-thick absorber, an atomic layer deposited wide bandgap Zn(O,S) buffer is introduced as the replacement of conventional CdS buffer, which partially limits incoming light less than 520 nm in wavelength. As a replacement result, more incoming light becomes valid for power conversion, and the short circuit current density (Jsc ) has increased comparatively by 17%, which has directly lead to a large increase in PCE up to 12.41%. Furthermore, Zn(O,S) buffer in the STUT CIGSe solar cell also has enhanced the bifacial compatible efficiency (BCE), which has increased to 14.44% at 1.3 sun and 19.42% at 2.0 sun., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)- Published
- 2022
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42. Analysis of the Efficacy of Universal Screening of Coronavirus Disease with Antigen-Detecting Rapid Diagnostic Tests at Point-or-Care Settings and Sharing the Experience of Admission Protocol-A Pilot Study.
- Author
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Park JY, Lee JH, Cha BK, Kim BS, Lee HJ, Kim GH, Kang KT, Lee YS, Ahn SK, and Kim SH
- Abstract
Aims: To introduce the admission protocol of a COVID-19 specialized hospital outlined by the government, including the assessment of reverse transcription polymerase chain reaction (RT-PCR), low dose chest computed tomography (CT) and antigen-detecting rapid diagnostic test (Ag-RDT) for patient screening., Materials and Methods: This was a retrospective cohort study of 646 patients who were admitted between December 2020, and February 2021, during the third wave of COVID-19 in Korea. Ag-RDT and RT-PCR were routinely performed on all patients who required admission, and low-dose chest CT was performed on high-risk patients with associated symptoms. Any patients with high-risk COVID-19 infection according to the Ag-RDT test were quarantined alone in a negative pressured room, and those with low-risk COVID-19 infection remained in the preemptive quarantine room with or without negative pressure. The diagnostic values of the Ag-RDT test and associated cycle threshold (Ct) values of the RT-PCR test were subsequently evaluated., Results: In terms of the diagnostic value, the Ag-RDT for COVID-19 had a sensitivity of 68.3%, specificity of 99.5%, positive predictive value (PPV) of 90.3%, and negative predictive value (NPV) of 97.9%. For the 355 symptomatic patients with low-dose chest CT, the diagnostic values of combined evaluations had a sensitivity of 90.2%, specificity of 99.0%, PPV of 86.1%, and NPV of 99.3%. The cut-off Ct value for positive Ag-RDT was ≤25.67 for the N gene (sensitivity: 89.3%, specificity: 100%), which was regarded as a high viable virus in cell culture. There were no patients or medical staff who had COVID-19 in the hospital., Conclusion: Appropriate patient care was possible by definitive triage of the area, according to the symptoms and using diagnostic tests. Screening protocols, including the Ag-RDT test and low-dose chest CT, could be helpful in emergency point-of-care settings.
- Published
- 2022
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43. Decrease of ceramides with long-chain fatty acids in psoriasis: Possible inhibitory effect of interferon gamma on chain elongation.
- Author
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Kim BK, Shon JC, Seo HS, Liu KH, Lee JW, Ahn SK, and Hong SP
- Subjects
- Animals, Epidermis metabolism, Fatty Acids metabolism, Interferon-gamma metabolism, Mice, Peroxisome Proliferator-Activated Receptors metabolism, Ceramides metabolism, Psoriasis drug therapy, Psoriasis metabolism
- Abstract
Reportedly, decreases in fatty acid (FA) chain length of ceramide (CER) are associated with interferon-γ (IFN-γ), which shows increased expression in psoriasis. However, the underlying mechanism of this association remains unclear. Therefore, in this study, we aimed to clarify this association between FA chain length of CER, IFN-γ, and the major transcriptional factors involving psoriasis. CER profiling according to FA chain length and class was performed in murine epidermis (n = 10 BALB/c mice topically treated with imiquimod, n = 10 controls) and human stratum corneum (SC) (n = 12 psoriasis, n = 11 controls). The expression of lipid synthetic enzymes, including elongases (ELOVLs), in murine epidermis was also measured using RT-PCR. Furthermore, the association of IFN-γ with various enzymes and transcription factors involved in the generation of long-chain CERs was also investigated using in vitro keratinocyte. A significant decrease in the percentage of long-chain CERs was observed in psoriasis-like murine epidermis and human psoriatic SC. Additionally, the expression levels of ELOVL1, ELOVL4, and ceramide synthase3 (CerS3) were significantly decreased in psoriasis-like murine epidermis and IFN-γ-treated keratinocyte. There was also a significant decrease in the expression of transcriptional factors, including peroxisome proliferator-activated receptor (PPAR), in IFN-γ treated keratinocyte. Thus, it could be suggested that IFN-γ may regulate ELOVL and CerS levels by down-regulating the transcriptional factors. Additionally, given the possible involvement of PPARs or liver X receptor agonist in the CER elongation process, they may serve as potential therapeutic agents for lengthening the CER FAs in psoriasis., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2022
- Full Text
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44. Targeting regulation of ATP synthase 5 alpha/beta dimerization alleviates senescence.
- Author
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Lee YH, Choi D, Jang G, Park JY, Song ES, Lee H, Kuk MU, Joo J, Ahn SK, Byun Y, and Park JT
- Subjects
- Adenosine Triphosphate metabolism, Cellular Senescence, Dimerization, Protein Binding, 14-3-3 Proteins genetics, Oxidative Phosphorylation
- Abstract
Senescence is a distinct set of changes in the senescence-associated secretory phenotype (SASP) and leads to aging and age-related diseases. Here, we screened compounds that could ameliorate senescence and identified an oxazoloquinoline analog (KB1541) designed to inhibit IL-33 signaling pathway. To elucidate the mechanism of action of KB1541, the proteins binding to KB1541 were investigated, and an interaction between KB1541 and 14-3-3ζ protein was found. Specifically, KB1541 interacted with 14-3-3ζ protein and phosphorylated of 14-3-3ζ protein at serine 58 residue. This phosphorylation increased ATP synthase 5 alpha/beta dimerization, which in turn promoted ATP production through increased oxidative phosphorylation (OXPHOS) efficiency. Then, the increased OXPHOS efficiency induced the recovery of mitochondrial function, coupled with senescence alleviation. Taken together, our results demonstrate a mechanism by which senescence is regulated by ATP synthase 5 alpha/beta dimerization upon fine-tuning of KB1541-mediated 14-3-3ζ protein activity.
- Published
- 2022
- Full Text
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45. Preclinical evaluation of a SARS-CoV-2 mRNA vaccine PTX-COVID19-B.
- Author
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Liu J, Budylowski P, Samson R, Griffin BD, Babuadze G, Rathod B, Colwill K, Abioye JA, Schwartz JA, Law R, Yip L, Ahn SK, Chau S, Naghibosadat M, Arita Y, Hu Q, Yue FY, Banerjee A, Hardy WR, Mossman K, Mubareka S, Kozak RA, Pollanen MS, Martin Orozco N, Gingras AC, Marcusson EG, and Ostrowski MA
- Subjects
- Animals, Antibodies, Neutralizing blood, Antibodies, Viral blood, CD4 Lymphocyte Count, CD8-Positive T-Lymphocytes immunology, COVID-19 immunology, COVID-19 Vaccines adverse effects, Canada, Cell Line, Cricetinae, Drug Evaluation, Preclinical, Female, HEK293 Cells, Humans, Immunity, Cellular immunology, Immunity, Humoral immunology, Liposomes pharmacology, Male, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Nanoparticles, Spike Glycoprotein, Coronavirus genetics, Th1 Cells immunology, COVID-19 prevention & control, COVID-19 Vaccines immunology, SARS-CoV-2 immunology, Spike Glycoprotein, Coronavirus immunology, Vaccines, Synthetic immunology, mRNA Vaccines immunology
- Abstract
Safe and effective vaccines are needed to end the COVID-19 pandemic. Here, we report the preclinical development of a lipid nanoparticle–formulated SARS-CoV-2 mRNA vaccine, PTX-COVID19-B. PTX-COVID19-B was chosen among three candidates after the initial mouse vaccination results showed that it elicited the strongest neutralizing antibody response against SARS-CoV-2. Further tests in mice and hamsters indicated that PTX-COVID19-B induced robust humoral and cellular immune responses and completely protected the vaccinated animals from SARS-CoV-2 infection in the lung. Studies in hamsters also showed that PTX-COVID19-B protected the upper respiratory tract from SARS-CoV-2 infection. Mouse immune sera elicited by PTX-COVID19-B vaccination were able to neutralize SARS-CoV-2 variants of concern, including the Alpha, Beta, Gamma, and Delta lineages. No adverse effects were induced by PTX-COVID19-B in either mice or hamsters. Based on these results, PTX-COVID19-B was authorized by Health Canada to enter clinical trials in December 2020 with a phase 2 clinical trial ongoing.
- Published
- 2022
- Full Text
- View/download PDF
46. Secular trends and related factors in leisure-time sedentary behavior among Koreans: an analysis of data from the 2011-2017 Korea Community Health Survey.
- Author
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Seo HJ, Choi MJ, and Ahn SK
- Subjects
- Adult, Female, Health Behavior, Humans, Leisure Activities, Male, Republic of Korea epidemiology, Surveys and Questionnaires, Public Health, Sedentary Behavior
- Abstract
Objectives: Sedentary behavior has gradually increased and has become a public health problem. Therefore, this study investigated trends in weekday leisure-time sedentary behaviors, as well as characteristic socio-demographic and lifestyle correlates in Korean adults., Methods: We analyzed data from 914,946 adults aged ≥19 years who participated in the Korea Community Health Survey (2011, 2013, 2015, and 2017). Leisure-time sedentary behavior was categorized as a binary variable (<4 and ≥4 hr/day). Multivariable regression analysis was used to model the prevalence of sedentary behavior and estimate odds ratios., Results: The prevalence of leisure-time sedentary behavior decreased from 15.2% to 14.4% in men and from 16.6% to 16.0% in women between 2011 and 2017, respectively. However, a significant increase was observed in subjects with an education lower than high school in both genders (β coefficient=0.12 for men and 0.08 for women, p for trend <0.001). Women in the lowest household income level (β coefficient=0.08, p for trend=0.001) and with poor subjective health status (β coefficient=0.05, p for trend=0.013) showed an increasing trend. Other factors associated with sedentary behavior were age, education level, body mass index, household income, walking activity, perceived stress level, and subjective health status in both genders., Conclusions: Identifying the secular trends and correlates of sedentary behavior by gender and associated factors will provide empirical evidence for developing public health campaigns and promotion programs to reduce sedentary behavior in Koreans.
- Published
- 2022
- Full Text
- View/download PDF
47. Incidence and Risk Factors for Progression to Diabetes Mellitus: A Retrospective Cohort Study.
- Author
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Hyun MK, Park JH, Kim KH, Ahn SK, and Ji SM
- Subjects
- Blood Glucose, Female, Follow-Up Studies, Humans, Incidence, Retrospective Studies, Risk Factors, Diabetes Mellitus epidemiology, Diabetes Mellitus, Type 2 epidemiology
- Abstract
(1) Objective: This study examined the incidence and risk factors contributing to the progression to diabetes mellitus (DM) in a seven-year follow-up study of non-diabetic National Health Examinees. (2) Methods: For this retrospective observational cohort study, we used two national representative databases: the National Health Screening (HEALS) database 2009 and the National Health Insurance Service (NHIS) database 2009-2015. The eligible subjects without DM with blood sugar levels of <126 mg/dL were selected using the HEALS database. The subsequent follow-up and clinical outcomes were evaluated using the NHIS database. Cox proportional hazard regression was applied to examine the effects of the covariates on progression to diabetes. (3) Results: Among those who took part in the national health screening in 2009, 4,205,006 subjects who met the eligibility criteria were selected. Of these, 587,015 were diagnosed with DM during the follow-up by 2015. The incidence of progression from non-diabetes to DM was 14.0%, whereas that from impaired fasting glucose (IFG) to DM was 21.9%. Compared to the normal group, the newly diagnosed DM group was more likely to comprise older, female, currently smoking, and high-risk drinking participants and participants with IFG, hypertension, dyslipidemia, and metabolic syndrome. (4) Conclusions: This epidemiological study in the Republic of Korea found risk factors similar to those of other studies, but the incidence of progression to DM was 22.8 per 1000 person-years, which is higher than that previously reported. Hence, more care is needed to prevent DM.
- Published
- 2021
- Full Text
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48. Intranasal HD-Ad vaccine protects the upper and lower respiratory tracts of hACE2 mice against SARS-CoV-2.
- Author
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Cao H, Mai J, Zhou Z, Li Z, Duan R, Watt J, Chen Z, Bandara RA, Li M, Ahn SK, Poon B, Christie-Holmes N, Gray-Owen SD, Banerjee A, Mossman K, Kozak R, Mubareka S, Rini JM, Hu J, and Liu J
- Abstract
Background: The ongoing COVID-19 pandemic has resulted in 185 million recorded cases and over 4 million deaths worldwide. Several COVID-19 vaccines have been approved for emergency use in humans and are being used in many countries. However, all the approved vaccines are administered by intramuscular injection and this may not prevent upper airway infection or viral transmission., Results: Here, we describe a novel, intranasally delivered COVID-19 vaccine based on a helper-dependent adenoviral (HD-Ad) vector. The vaccine (HD-Ad_RBD) produces a soluble secreted form of the receptor binding domain (RBD) of the SARS-CoV-2 spike protein and we show it induced robust mucosal and systemic immunity. Moreover, intranasal immunization of K18-hACE2 mice with HD-Ad_RBD using a prime-boost regimen, resulted in complete protection of the upper respiratory tract against SARS-CoV-2 infection., Conclusion: Our approaches provide a powerful platform for constructing highly effective vaccines targeting SARS-CoV-2 and its emerging variants., (© 2021. The Author(s).)
- Published
- 2021
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49. Medical Staff of Swedish Methodist Hospital.
- Author
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Ahn SK, Koh SB, Yoon JW, Lee SH, and Lee S
- Subjects
- Humans, Medical Staff, Sweden, Hospitals, Protestantism
- Abstract
Competing Interests: The authors have no potential conflicts of interest to disclose.
- Published
- 2021
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- View/download PDF
50. Monitoring of Oxygen in Simulated Electrolytic Reduction Salt of Pyroprocessing Using Laser-Induced Breakdown Spectroscopy.
- Author
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Park SH, Han SK, and Ahn SK
- Abstract
Laser-induced breakdown spectroscopy (LIBS) was explored as a method of monitoring oxygen (O) concentration in electrolytic reduction salt of pyroprocessing. Simulated salt samples were fabricated, and each sample was put in a transparent and sealed vial filled with argon gas. An neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulse was applied to the sample through the vial surface, and the optical emission spectrum was measured. O(I) 777.2 nm lines were clearly identified in the spectrum of a sample containing Li
2 O, and the intensity of the O peak and the intensity ratio of O and lithium (Li) peaks, in which Li was used as the normalization, increased linearly as the O concentration in the salt sample was increased. The limit of detection and root mean square error were calculated for the cases of O peak area, O peak height, peak area ratio of O-Li, and the peak height ratio of O-Li, and all the cases could indicate that the O concentration in the electrolytic reduction salt was out of normal range. Our result shows that LIBS has the possibility to be used as a method for monitoring of O in electrolytic reduction salt.- Published
- 2021
- Full Text
- View/download PDF
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