Publications by authors named "Jihoon Kim"

305 Publications

Improved Contact Resistance by a Single Atomic Layer Tunneling Effect in WS /MoTe Heterostructures.

Adv Sci (Weinh) 2021 Jun 15;8(11):e2100102. Epub 2021 Mar 15.

School of Electronic and Electrical Engineering, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.

Manipulation of Ohmic contacts in 2D transition metal dichalcogenides for enhancing the transport properties and enabling its application as a practical device has been a long-sought goal. In this study, n-type tungsten disulfide (WS ) single atomic layer to improve the Ohmic contacts of the p-type molybdenum ditelluride (MoTe ) material is covered. The Ohmic properties, based on the lowering of Schottky barrier height (SBH) owing to the tunneling barrier effect of the WS monolayer, are found to be unexpectedly excellent at room temperature and even at 100 K. The improved SBH and contact resistances are 3 meV and 1 MΩ µm, respectively. The reduction in SBH and contact resistance is confirmed with temperature-dependent transport measurements. This study further demonstrates the selective carrier transport across the MoTe and WS layers by modulating the applied gate voltage. This WS /MoTe heterostructure exhibits excellent gate control over the currents of both channels (n-type and p-type). The on/off ratios for both the electron and hole channels are calculated as 10 and 10 , respectively, indicating good carrier type modulation by the electric field of the gate electrode. The Ohmic contact resistance using the tunneling of the atomic layer can be applied to heterojunction combinations of various materials.
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http://dx.doi.org/10.1002/advs.202100102DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8188188PMC
June 2021

Prevalence, awareness, treatment, and control of diabetes mellitus by depressive symptom severity: a cross-sectional analysis of NHANES 2011-2016.

BMJ Open Diabetes Res Care 2021 06;9(1)

Department of Biomedical Sciences, Seoul National University Hospital, Seoul, Korea (the Republic of)

Introduction: Despite extensive studies on the relationship between diabetes mellitus (DM) and depression, the associations of depressive symptom severity with prevalence, awareness, treatment, and control of diabetes remain unclear. We aimed to investigate changes in these outcomes of diabetes as depressive symptoms aggravate.

Research Design And Methods: We conducted a cross-sectional analysis of 14 328 participants in the 2011-2016 National Health and Nutrition Examination Survey. Participants were classified into depressive symptom groups of none, mild, moderate, moderately severe, and severe depending on their Patient Health Questionnaire-9 scores. Multivariate logistic regression analyses were conducted in three models adjusted for expanding confounders to evaluate the associations between severity of depressive symptoms and prevalence, awareness, treatment, and control of DM.

Results: As depressive symptom severity worsened, both prevalence and awareness of DM increased regardless of models (p value for trend <0.01 in all models for prevalence and awareness; adjusted OR (aOR) 2.14, 95% CI 1.29 to 3.56 for prevalence in the severe group, model 1; aOR 2.43, 95% CI 1.27 to 4.64 for awareness in the moderately severe group, model 1). Notwithstanding higher awareness of diabetes in the moderately severe and severe groups (84.5% and 86.2%, respectively, vs 71.3% in the none group), these groups were treated less (aOR 0.25, 95% CI 0.11 to 0.55 in the severe group, model 3) or inadequately controlled (aOR 0.51, 95% CI 0.27 to 0.98 in the moderately severe group, model 3).

Conclusions: The gap between patients' higher awareness and lower treatment rate or control of diabetes among individuals with severe depressive symptoms highlights the unmet needs for postdiagnostic multidisciplinary care for patients with comorbid depression and DM.
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http://dx.doi.org/10.1136/bmjdrc-2021-002268DOI Listing
June 2021

Kawasaki Disease Patient Stratification and Pathway Analysis Based on Host Transcriptomic and Proteomic Profiles.

Int J Mol Sci 2021 May 26;22(11). Epub 2021 May 26.

Faculty of Medicine, Imperial College London, London SW7 2AZ, UK.

The aetiology of Kawasaki disease (KD), an acute inflammatory disorder of childhood, remains unknown despite various triggers of KD having been proposed. Host 'omic profiles offer insights into the host response to infection and inflammation, with the interrogation of multiple 'omic levels in parallel providing a more comprehensive picture. We used differential abundance analysis, pathway analysis, clustering, and classification techniques to explore whether the host response in KD is more similar to the response to bacterial or viral infections at the transcriptomic and proteomic levels through comparison of 'omic profiles from children with KD to those with bacterial and viral infections. Pathways activated in patients with KD included those involved in anti-viral and anti-bacterial responses. Unsupervised clustering showed that the majority of KD patients clustered with bacterial patients on both 'omic levels, whilst application of diagnostic signatures specific for bacterial and viral infections revealed that many transcriptomic KD samples had low probabilities of having bacterial or viral infections, suggesting that KD may be triggered by a different process not typical of either common bacterial or viral infections. Clustering based on the transcriptomic and proteomic responses during KD revealed three clusters of KD patients on both 'omic levels, suggesting heterogeneity within the inflammatory response during KD. The observed heterogeneity may reflect differences in the host response to a common trigger, or variation dependent on different triggers of the condition.
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http://dx.doi.org/10.3390/ijms22115655DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8198135PMC
May 2021

Recent Advances in High-Throughput Nanomaterial Manufacturing for Hybrid Flexible Bioelectronics.

Materials (Basel) 2021 May 31;14(11). Epub 2021 May 31.

Center for Human-Centric Interfaces, George W. Woodruff School of Mechanical Engineering, Engineering at the Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA 30332, USA.

Hybrid flexible bioelectronic systems refer to integrated soft biosensing platforms with tremendous clinical impact. In this new paradigm, electrical systems can stretch and deform with the skin while previously hidden physiological signals can be continuously recorded. However, hybrid flexible bioelectronics will not receive wide clinical adoption until these systems can be manufactured at industrial scales cost-effectively. Therefore, new manufacturing approaches must be discovered and studied under the same innovative spirit that led to the adoption of novel materials and soft structures. Recent works have taken mature manufacturing approaches from the graphics industry, such as gravure, flexography, screen, and inkjet printing, and applied them to fully printed bioelectronics. These applications require the cohesive study of many disparate parts. For instance, nanomaterials with optimal properties for each specific application must be dispersed in printable inks with rheology suited to each printing method. This review summarizes recent advances in printing technologies, key nanomaterials, and applications of the manufactured hybrid bioelectronics. We also discuss the existing challenges of the available nanomanufacturing methods and the areas that need immediate technological improvements.
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http://dx.doi.org/10.3390/ma14112973DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8197924PMC
May 2021

Privacy-protecting, reliable response data discovery using COVID-19 patient observations.

J Am Med Inform Assoc 2021 May 29. Epub 2021 May 29.

UC San Diego Health Department of Biomedical Informatics, University of California San Diego, La Jolla, California, USA.

Objective: To utilize, in an individual and institutional privacy-preserving manner, electronic health record (EHR) data from 202 hospitals by analyzing answers to COVID-19-related questions and posting these answers online.

Materials And Methods: We developed a distributed, federated network of 12 health systems that harmonized their EHRs and submitted aggregate answers to consortia questions posted at https://www.covid19questions.org. Our consortium developed processes and implemented distributed algorithms to produce answers to a variety of questions. We were able to generate counts, descriptive statistics, and build a multivariate, iterative regression model without centralizing individual-level data.

Results: Our public website contains answers to various clinical questions, a web form for users to ask questions in natural language, and a list of items that are currently pending responses. The results show, for example, that patients who were taking angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, within the year before admission, had lower unadjusted in-hospital mortality rates. We also showed that, when adjusted for, age, sex, and ethnicity were not significantly associated with mortality. We demonstrated that it is possible to answer questions about COVID-19 using EHR data from systems that have different policies and must follow various regulations, without moving data out of their health systems.

Discussion And Conclusions: We present an alternative or a complement to centralized COVID-19 registries of EHR data. We can use multivariate distributed logistic regression on observations recorded in the process of care to generate results without transferring individual-level data outside the health systems.
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http://dx.doi.org/10.1093/jamia/ocab054DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8194878PMC
May 2021

Prognosis of Myocardial Injury After Non-Cardiac Surgery in Adults Aged Younger Than 45 Years.

Circ J 2021 May 12. Epub 2021 May 12.

Division of Cardiology, Department of Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine.

Background: This study compared myocardial injury after non-cardiac surgery (MINS) and mortalities between patients under and over the age of 45 years.Methods and Results:From January 2010 and June 2019, patients with cardiac troponin measurement within 30 days after non-cardiac surgery were enrolled and divided into groups according to age: >45 (≥45 years) and <45 (<45 years). Further analyses were conducted only in patients who were diagnosed with MINS. The outcomes were MINS and 30-day mortality. Of the 35,223 patients, 31,161 (88.5%) patients were in the >45-year group and 4,062 (11.5%) were in the <45-year group. After adjustment with inverse probability of weighting, the <45-years group showed a lower incidence of MINS and cardiovascular mortality (16.6% vs. 11.7%; odds ratio, 0.77; 95% confidence interval [CI], 0.69-0.84; P<0.001 and 0.4% vs. 0.2%; hazard ratio [HR], 0.41; 95% CI, 0.19-0.88; P=0.02, respectively). In a comparison of only the <45-years group, MINS was associated with increased 30-day mortality (0.7% vs. 10.3%; HR, 10.48; 95% CI, 6.18-17.78; P<0.001), but the mortalities of patients with MINS did not differ according to age.

Conclusions: MINS has a comparable prognostic impact in patients aged under and over 45 years; therefore, future studies need to also consider patients aged <45 years regarding risk factors of MINS and screening of perioperative troponin elevation.
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http://dx.doi.org/10.1253/circj.CJ-21-0106DOI Listing
May 2021

An AI-guided invariant signature places MIS-C with Kawasaki disease in a continuum of host immune responses.

bioRxiv 2021 Apr 12. Epub 2021 Apr 12.

A significant surge in cases of multisystem inflammatory syndrome in children (MIS-C, also called Pediatric Inflammatory Multisystem Syndrome - PIMS) has been observed amidst the COVID-19 pandemic. MIS-C shares many clinical features with Kawasaki disease (KD), although clinical course and outcomes are divergent. We analyzed whole blood RNA sequences, serum cytokines, and formalin fixed heart tissues from these patients using a computational toolbox of two gene signatures, i.e., the 166-gene viral pandemic (ViP) signature, and its 20-gene severe (s)ViP subset that were developed in the context of SARS-CoV-2 infection and a 13-transcript signature previously demonstrated to be diagnostic for KD. Our analyses revealed that KD and MIS-C are on the same continuum of the host immune response as COVID-19 but diverge with two different cardiac phenotypes. The ViP signatures helped unravel the nature of the host immune response (IL15-centric) in MIS-C and KD, reveal unique targetable cytokine pathways in MIS-C, place MIS-C farther along in the spectrum in severity compared to KD and pinpoint key clinical (reduced cardiac function) and laboratory (thrombocytopenia and eosinopenia) parameters that can be useful to monitor severity.
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http://dx.doi.org/10.1101/2021.04.11.439347DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8057241PMC
April 2021

Preoperative Right Ventricular Free-Wall Longitudinal Strain as a Prognosticator in Isolated Surgery for Severe Functional Tricuspid Regurgitation.

J Am Heart Assoc 2021 May 17;10(9):e019856. Epub 2021 Apr 17.

From the Cardiovascular Center Seoul National University Hospital Seoul Republic of Korea.

Background Severe tricuspid regurgitation (TR) should be intervened before the development of irreversible right ventricular (RV) dysfunction. However, current guidelines do not provide criterion related to RV systolic function to guide optimal surgical timing. We investigated the prognostic value of RV longitudinal strain in patients undergoing isolated surgery for severe functional TR. Methods and Results We enrolled 115 consecutive patients (aged 62±10 years; 23.5% men; 62.6% [n=72] with previous left-sided valve surgery) who underwent isolated surgery for severe functional TR at 2 tertiary centers. Preoperative clinical and echocardiographic parameters, including RV free-wall longitudinal strain (RVFWSL), were collected. The primary end point was a composite of cardiac death and unplanned readmission attributable to cardiovascular causes 5 years after surgery. Forty patients (34.8%) reached the primary end point during 333 person-years of follow-up. There were 11 cardiac deaths and 34 unplanned readmissions attributable to cardiovascular causes, with 5 patients experiencing both. An absolute preoperative RVFWSL <24% was associated with the primary end point (hazard ratio, 2.30; 95% CI, 1.22-4.36; =0.011), independent of clinical risk factors, including European System for Cardiac Operative Risk Evaluation II and hemoglobin levels. Meanwhile, other conventional echocardiographic measures of RV systolic function were not significant. The addition of an absolute RVFWSL <24% provided incremental prognostic value to the clinical model for predicting the primary end point. Conclusions Preoperative RVFWSL as an indicator of RV dysfunction was an independent prognosticator in patients undergoing isolated surgery for severe functional TR. Thus, preoperative RVFWSL could help determine the optimal surgical timing for severe functional TR.
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http://dx.doi.org/10.1161/JAHA.120.019856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8200727PMC
May 2021

Effects of Gamification on Behavioral Change in Education: A Meta-Analysis.

Int J Environ Res Public Health 2021 03 29;18(7). Epub 2021 Mar 29.

Health Behavior & Health Education, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX 78712, USA.

Background: Gamified reward systems, such as providing digital badges earned for specific accomplishments, are related to student engagement in educational settings. The purpose of this study was to conduct a meta-analytic review to quantify the effects of gamified interventions on student behavioral change.

Methods: A meta-analysis was performed using the following databases: The Academic Search Complete, Communication & Mass Media Complete, Education Source, ERIC, Library Information Science & Technology Abstracts, and PsycINFO. Inclusion in the review required: (a) peer-reviewed conducted between 2010 and 2019, (b) experimental controlled design, (c) gamification elements, and (d) educational setting.

Results: Using a random-effects model, a statistically significant (Cohen's d (ES) = 0.48, 95% CI = 0.33, 0.62) gamification effect was evidenced by moderate and positive grand effects sizes (ES). Gamification effects were higher with adults in higher education (ES = 0.95) than K-12 students (ES = 0.92). Brief interventions delivered in days or less than 1 week were significantly more effective (ES = 1.57) than interventions lasting up to 20 weeks (ES = 0.30). Interventions incorporating gamification elements across years (ES = -0.20) was adversely associated with behavioral change.

Conclusions: Findings suggest that short-term over longer-term gamified interventions might be a promising way to initiate changes in learner's behaviors and improve learning outcome.
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http://dx.doi.org/10.3390/ijerph18073550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8037535PMC
March 2021

Bombesin-Tethered Reactive Oxygen Species (ROS)-Responsive Nanoparticles for Monomethyl Auristatin F (MMAF) Delivery.

Bioengineering (Basel) 2021 Mar 29;8(4). Epub 2021 Mar 29.

Yong Loo Lin School of Medicine and Faculty of Engineering, National University of Singapore, Singapore 117597, Singapore.

Dolastatin derivatives, represented by monomethylauristatin E (MMAE), have been translated in clinic with a form of antibody-drug conjugate; however, their potential in nanoparticle systems has not been well established due to the potential risk of immature release of extremely high cytotoxic dolastatin drugs during blood circulation. Herein, we rationally propose monomethylauristatin F (MMAF), a dolastatin-derived, loaded nanoparticle system composed of bombesin (BBN)-tethered ROS-responsive micelle system (BBN-PEG-PPADT) to achieve efficient anticancer therapy with targeted and efficient delivery of MMAF. The developed MMAF-loaded BBN-PEG-PPADT micelles ([email protected]) exhibited improved cellular uptake via interactions between BBN and gastrin-releasing peptide receptors on the cancer cells and the intracellular burst release of MMAF, owing to the ROS-responsive disruption, which allowed the efficient anticancer effects of MMAF in vitro. This study suggests the potential of nanoparticle systems in the delivery of dolastatin drugs.
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http://dx.doi.org/10.3390/bioengineering8040043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8066503PMC
March 2021

Identification of novel locus associated with coronary artery aneurysms and validation of loci for susceptibility to Kawasaki disease.

Eur J Hum Genet 2021 Mar 26. Epub 2021 Mar 26.

Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK.

Kawasaki disease (KD) is a paediatric vasculitis associated with coronary artery aneurysms (CAA). Genetic variants influencing susceptibility to KD have been previously identified, but no risk alleles have been validated that influence CAA formation. We conducted a genome-wide association study (GWAS) for CAA in KD patients of European descent with 200 cases and 276 controls. A second GWAS for susceptibility pooled KD cases with healthy paediatric controls from vaccine trials in the UK (n = 1609). Logistic regression mixed models were used for both GWASs. The susceptibility GWAS was meta-analysed with 400 KD cases and 6101 controls from a previous European GWAS, these results were further meta-analysed with Japanese GWASs at two putative loci. The CAA GWAS identified an intergenic region of chromosome 20q13 with multiple SNVs showing genome-wide significance. The risk allele of the most associated SNV (rs6017006) was present in 13% of cases and 4% of controls; in East Asian 1000 Genomes data, the allele was absent or rare. Susceptibility GWAS with meta-analysis with previously published European data identified two previously associated loci (ITPKC and FCGR2A). Further meta-analysis with Japanese GWAS summary data from the CASP3 and FAM167A genomic regions validated these loci in Europeans showing consistent effects of the top SNVs in both populations. We identified a novel locus for CAA in KD patients of European descent. The results suggest that different genes determine susceptibility to KD and development of CAA and future work should focus on the function of the intergenic region on chromosome 20q13.
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http://dx.doi.org/10.1038/s41431-021-00838-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7994355PMC
March 2021

Associations Between Preoperative Glucose and Hemoglobin A1c Level and Myocardial Injury After Noncardiac Surgery.

J Am Heart Assoc 2021 Apr 17;10(7):e019216. Epub 2021 Mar 17.

Department of Anesthesiology and Pain Medicine Samsung Medical CenterSungkyunkwan University School of Medicine Seoul Korea.

Background Perioperative blood glucose level has shown an association with postoperative outcomes. We compared the incidences of myocardial injury after noncardiac surgery (MINS) and 30-day mortality, according to preoperative blood glucose and hemoglobin A1c (HbA1c) levels. Methods and Results The patients were divided according to blood glucose level within 1 day before surgery. The hyperglycemia group was defined with fasting glucose >140 mg/dL or random glucose >180 mg/dL. In addition, we compared the outcomes according to HbA1c >6.5% among patients with available HbA1c within 3 months before surgery. The primary outcome was MINS, and 30-day mortality was also compared. A total of 12 304 patients were enrolled and divided into 2 groups: 8324 (67.7%) in the normal group and 3980 (32.3%) in the hyperglycemia group. After adjustment with inverse probability of weighting, the hyperglycemia group exhibited significantly higher incidences of MINS and 30-day mortality (18.7% versus 27.6%; odds ratio, 1.29; 95% CI, 1.18-1.42; <0.001; and 2.0% versus 5.1%; hazard ratio, 2.00; 95% CI, 1.61-2.49; <0.001, respectively). In contrast to blood glucose, HbA1c was not associated with MINS or 30-day mortality. Conclusions Preoperative hyperglycemia was associated with MINS and 30-day mortality, whereas HbA1c was not. Immediate glucose control may be more crucial than long-term glucose control in patients undergoing noncardiac surgery. Registration URL: https://www.cris.nih.go.kr; Unique identifier: KCT0004244.
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http://dx.doi.org/10.1161/JAHA.120.019216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8174354PMC
April 2021

Dimension Effect of Sapphire Substrate in Current-Switching Device Based on Vanadium Dioxide Thin Film Controlled by Photothermal Effect.

J Nanosci Nanotechnol 2021 Aug;21(8):4285-4292

School of Electrical Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Korea.

The switching characteristics of a vanadium dioxide (VO₂) thin-film device, in which the current flowing through the device can be switched through the photothermal effect using focused laser pulses, were investigated according to the dimensions of the sapphire substrate on which the VO₂ thin film was deposited through simulation using COMSOL Multiphysics. The physical properties of the VO₂ device, modeled for the simulation, were determined according to the structural and electrical properties and photothermally controlled current-switching characteristics of fabricated VO₂ devices. For a variety of substrate dimensions of the modeled VO₂ device, we explored transient variations in the temperature of some specific regions and the device current switched by laser irradiation. The investigation results revealed that the stability of the bidirectional current-switching operation triggered on and off by laser illumination tends to increase as the area of the substrate increases with its thickness fixed. However, above a certain substrate area, the rate of improvement in the switching stability decreases rapidly and approaches zero.
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http://dx.doi.org/10.1166/jnn.2021.19402DOI Listing
August 2021

Simultaneous Measurement of pH and Temperature with Phase-Shifted Long-Period Fiber Grating Inscribed on High-Birefringence Fiber by CO₂ Laser Pulses.

J Nanosci Nanotechnol 2021 Aug;21(8):4268-4276

Industry 4.0 Convergence Bionics Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Korea.

We propose an optical fiber grating sensor capable of simultaneously measuring pH and temperature based on a phase-shifted long-period fiber grating (PS-LPFG) inscribed on high-birefringence fiber (HBF). The PS-LPFG was fabricated on HBF with CO₂ laser pulses, and a phase shift was induced by inserting a grating-free fiber region (GFFR) between two identical LPFGs with a grating period of ˜510 m. The length of the GFFR was set as half of the grating period to induce a phase shift. With the spectral characteristics of a -PS-LPFG exhibiting two split attenuation bands, the PS-LPFG written on HBF, which is referred to as the HB-PS-LPFG, can create two polarization-dependent transmission spectra with dual-resonance dips at different wavelengths according to two orthogonal input polarization states, e.g., linear horizontal polarization (LHP) and linear vertical polarization (LVP). For simultaneous measurement of pH and temperature with the fabricated HB-PS-LPFG as a sensor head, the inter-resonance wavelength separation of the dual-resonance dips in each transmission spectrum obtained for an LHP or LVP input signal was exploited as a sensor indicator. By investigating the wavelength changes of the two sensor indicators, which were induced by pH and temperature variations, linear and independent spectral responses to both pH and temperature variations were experimentally confirmed in a pH range from 1 to 11 and a temperature range from 25 to 65 °C. Owing to the unique pH and temperature responses of the fabricated HB-PS-LPFG, ambient variations in pH and temperature could be simultaneously estimated from the measured wavelength changes and sensitivities of the two sensor indicators.
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http://dx.doi.org/10.1166/jnn.2021.19404DOI Listing
August 2021

Simultaneous Measurement of Torsion and Temperature Based on -Phase-Shifted Long-Period Fiber Grating Inscribed on Double-Clad Fiber.

J Nanosci Nanotechnol 2021 Aug;21(8):4243-4251

Industry 4.0 Convergence Bionics Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Korea.

In this work, we experimentally demonstrated an optical fiber sensor capable of performing simultaneous measurement of torsion and temperature using a -phase-shifted long-period fiber grating (LPFG) inscribed on double-clad fiber (DCF), referred to as a PS-DC-LPFG. The fabricated PSDC- LPFG showed split attenuation bands near its resonance wavelength, and the two dips in these bands were selected as sensor indicators, denoted as Dips A and B, for the simultaneous measurement of torsion and temperature. The torsion and temperature responses of the two indicators were investigated in a twist angle range from -360° to 360° and a temperature range from 30 to 120 °C, respectively. When the twist angle increased from 0° to 360° (clockwise) at room temperature, both Dips A and B showed redshifts. On the contrary, when the twist angle decreased from 0° to -360° (counterclockwise), the two dips showed blueshifts. In terms of temperature responses, both dips showed redshifts with increasing ambient temperature while the sensor head (i.e., the PS-DC-LPFG) remained straight without any applied torsion. Owing to their linear and independent responses to torsion and temperature, the changes in torsion and temperature applied to the PSDC- LPFG could be simultaneously estimated from the measured wavelength shifts and calculated sensitivities of the two indicator dips.
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http://dx.doi.org/10.1166/jnn.2021.19403DOI Listing
August 2021

Crosslinked Hydrogel Depot for Sustained Antibody Release Improves Immune Checkpoint Blockade Cancer Immunotherapy.

Nanomaterials (Basel) 2021 Feb 12;11(2). Epub 2021 Feb 12.

Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 315 Ferst Dr NW, Atlanta, GA 30332, USA.

The therapeutic inhibition of immune checkpoints, including cytotoxic T lymphocyte-associated protein (CTLA)-4 and programmed cell death 1 (PD-1), through the use of function blocking antibodies can confer improved clinical outcomes by invigorating CD8 T cell-mediated anticancer immunity. However, low rates of patient responses and the high rate of immune-related adverse events remain significant challenges to broadening the benefit of this therapeutic class, termed immune checkpoint blockade (ICB). To overcome these significant limitations, controlled delivery and release strategies offer unique advantages relevant to this therapeutic class, which is typically administered systemically (e.g., intravenously), but more recently, has been shown to be highly efficacious using locoregional routes of administration. As such, in this paper, we describe an crosslinked hydrogel for the sustained release of antibodies blocking CTLA-4 and PD-1 signaling from a locoregional injection proximal to the tumor site. This formulation results in efficient and durable anticancer effects with a reduced systemic toxicity compared to the bolus delivery of free antibody using an equivalent injection route. This formulation and strategy thus represent an approach for achieving the efficient and safe delivery of antibodies for ICB cancer immunotherapy.
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http://dx.doi.org/10.3390/nano11020471DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7918828PMC
February 2021

Effect of a Nitrite/Nitrate-Based Accelerator on the Strength Development and Hydrate Formation in Cold-Weather Cementitious Materials.

Materials (Basel) 2021 Feb 20;14(4). Epub 2021 Feb 20.

Basic Chemicals Department Chemicals Division, Nissan Chemical Corporation, Tokyo 103-6119, Japan.

Recently, there has been increased use of calcium-nitrite and calcium-nitrate as the main components of chloride- and alkali-free anti-freezing agents to promote concrete hydration in cold weather concreting. As the amount of nitrite/nitrate-based accelerators increases, the hydration of tricalcium aluminate (CA phase) and tricalcium silicate (CS phase) in cement is accelerated, thereby improving the early strength of cement and effectively preventing initial frost damage. Nitrite/nitrate-based accelerators are used in larger amounts than usual in low temperature areas below -10 °C. However, the correlation between the hydration process and strength development in concrete containing considerable nitrite/nitrate-based accelerators remains to be clearly identified. In this study, the hydrate composition (via X-ray diffraction and nuclear magnetic resonance), pore structures (via mercury intrusion porosimetry), and crystal form (via scanning electron microscopy) were determined, and investigations were performed to elucidate the effect of nitrite/nitrate-based accelerators on the initial strength development and hydrate formation of cement. Nitrite/nitrate-AFm (aluminate-ferret-monosulfate; AFm) was produced in addition to ettringite at the initial stage of hydration of cement by adding a nitrite/nitrate-based accelerator. The amount of the hydrates was attributed to an increase in the absolute amounts of NO and NO ions reacting with AlO in the tricalcium aluminate (CA phase). Further, by effectively filling the pores, it greatly contributed to the enhancement of the strength of the hardened cement product, and the degree of the contribution tended to increase with the amount of addition. On the other hand, in addition to the occurrence of cracks due to the release of a large amount of heat of hydration, the amount of expansion and contraction may increase, and it is considered necessary to adjust the amount used for each concrete work.
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http://dx.doi.org/10.3390/ma14041006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7924375PMC
February 2021

Physical and Chemical Relationships in Accelerated Carbonation Conditions of Alkali-Activated Cement Based on Type of Binder and Alkali Activator.

Polymers (Basel) 2021 Feb 23;13(4). Epub 2021 Feb 23.

Department of Civil Engineering and Architecture, Muroran Institute of Technology, Hokkaido 050-8585, Japan.

Alkali-activated cements prepared from aluminosilicate powders, such as blast furnace slag and fly ash, are rapidly attracting attention as alternatives to cement because they can significantly reduce CO emissions compared to conventional cement concrete. In this study, we investigated the relationship between the physical and chemical changes by accelerated carbonation conditions of alkali-activated cements. Alkali-activated cements were prepared from binders composed of blast furnace slag and fly ash as well as alkali activators sodium silicate and sodium hydroxide. Physical changes were analyzed from compressive strength, pH, and neutralization depth, and chemical changes were analyzed from XRD, TG-DTG, and Si MAS NMR. The C-(N)-A-S-H structure is noted to change via carbonation, and the compressive strength is observed to decrease. However, in the case of Na-rich specimens, the compressive strength does not decrease by accelerated carbonation. This work is expected to contribute to the field of alkali-activated cements in the future.
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http://dx.doi.org/10.3390/polym13040671DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7926754PMC
February 2021

Intraoperative blood loss may be associated with myocardial injury after non-cardiac surgery.

PLoS One 2021 24;16(2):e0241114. Epub 2021 Feb 24.

Division of Cardiology, Department of Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

Background: This study aimed to evaluate the association between intraoperative blood loss and myocardial injury after non-cardiac surgery (MINS), which is a severe and common postoperative complication.

Methods: We compared the incidence of MINS based on significant intraoperative bleeding, defined as an absolute hemoglobin level < 7 g/dL, a relative hemoglobin level less than 50% of the preoperative measurement, or need for packed red cell transfusion. We also estimated a threshold for intraoperative hemoglobin level associated with MINS.

Results: We stratified a total of 15,926 non-cardiac surgical patients with intraoperative hemoglobin and postoperative cardiac troponin (cTn) measurements according to the occurrence of significant intraoperative bleeding; 13,416 (84.2%) had no significant bleeding while 2,510 (15.8%) did have significant bleeding. After an adjustment with inverse probability weighting, the incidence of MINS was higher in the significant bleeding group (35.2% vs. 16.4%; odds ratio, 1.58; 95% confidence interval, 1.43-1.75; p < 0.001). The threshold of intraoperative hemoglobin associated with MINS was estimated to be 9.9 g/dL with an area under the curve of 0.643.

Conclusion: Intraoperative blood loss appeared to be associated with MINS. Further studies are needed to confirm these findings.

Clinical Registration: The cohort was registered before patient enrollment at https://cris.nih.go.kr (KCT0004244).
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0241114PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7904206PMC
February 2021

Multiplexed CRISPR-Cas9 system in a single adeno-associated virus to simultaneously knock out redundant clock genes.

Sci Rep 2021 Jan 28;11(1):2575. Epub 2021 Jan 28.

Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), E4-311, 333 Technojoongang-daero, Dalseong-gun, Daegu, 42988, South Korea.

The mammalian molecular clock is based on a transcription-translation feedback loop (TTFL) comprising the Period1, 2 (Per1, 2), Cryptochrome1, 2 (Cry1, 2), and Brain and Muscle ARNT-Like 1 (Bmal1) genes. The robustness of the TTFL is attributed to genetic redundancy among some essential clock genes, deterring genetic studies on molecular clocks using genome editing targeting single genes. To manipulate multiple clock genes in a streamlined and efficient manner, we developed a CRISPR-Cas9-based single adeno-associated viral (AAV) system targeting the circadian clock (CSAC) for essential clock genes including Pers, Crys, or Bmal1. First, we tested several single guide RNAs (sgRNAs) targeting individual clock genes in silico and validated their efficiency in Neuro2a cells. To target multiple genes, multiplex sgRNA plasmids were constructed using Golden Gate assembly and packaged into AAVs. CSAC efficiency was evident through protein downregulation in vitro and ablated molecular oscillation ex vivo. We also measured the efficiency of CSAC in vivo by assessing circadian rhythms after injecting CSAC into the suprachiasmatic nuclei of Cas9-expressing knock-in mice. Circadian locomotor activity and body temperature rhythms were severely disrupted in these mice, indicating that our CSAC is a simple yet powerful tool for investigating the molecular clock in vivo.
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http://dx.doi.org/10.1038/s41598-021-82287-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7844015PMC
January 2021

Lipid indices as simple and clinically useful surrogate markers for insulin resistance in the U.S. population.

Sci Rep 2021 Jan 27;11(1):2366. Epub 2021 Jan 27.

Department of Internal Medicine, Hallym University, Chuncheon, Republic of Korea.

This study aimed to compare the accuracy of novel lipid indices, including the visceral adiposity index (VAI), lipid accumulation product (LAP), triglycerides and glucose (TyG) index, TyG-body mass index (TyG-BMI), and TyG-waist circumference (TyG-WC), in identifying insulin resistance and establish valid cutoff values. This cross-sectional study used the data of 11,378 adults, derived from the United States National Health and Nutrition Examination Survey (1999-2016). Insulin resistance was defined as a homeostasis model assessment-insulin resistance value above the 75th percentile for each sex and race/ethnicities. The area under the curves (AUCs) were as follows: VAI, 0.735; LAP, 0.796; TyG index, 0.723; TyG-BMI, 0.823, and; TyG-WC, 0.822. The AUCs for TyG-BMI and TyG-WC were significantly higher than those for VAI, LAP, and TyG index (vs. TyG-BMI, p < 0.001; vs. TyG-WC, p < 0.001). The cutoff values were as follows: VAI: men 1.65, women 1.65; LAP: men 42.5, women 42.5; TyG index: men 4.665, women 4.575; TyG-BMI: men 135.5, women 135.5; and TyG-WC: men 461.5, women 440.5. Given that lipid indices can be easily calculated with routine laboratory tests, these values may be useful markers for insulin resistance risk assessments in clinical settings.
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http://dx.doi.org/10.1038/s41598-021-82053-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7840900PMC
January 2021

Predictive Analytics for Glaucoma Using Data From the All of Us Research Program.

Am J Ophthalmol 2021 Jul 23;227:74-86. Epub 2021 Jan 23.

UCSD Health Department of Biomedical Informatics, University of California San Diego, (S.L.B., B.R.S., P.P., J.K., L.B., T.-T.K., L.O.-M.), La Jolla, California; Division of Health Services Research and Development, Veterans Affairs San Diego Healthcare System, La Jolla, California (L.O.-M.), USA.

Purpose: To (1) use All of Us (AoU) data to validate a previously published single-center model predicting the need for surgery among individuals with glaucoma, (2) train new models using AoU data, and (3) share insights regarding this novel data source for ophthalmic research.

Design: Development and evaluation of machine learning models.

Methods: Electronic health record data were extracted from AoU for 1,231 adults diagnosed with primary open-angle glaucoma. The single-center model was applied to AoU data for external validation. AoU data were then used to train new models for predicting the need for glaucoma surgery using multivariable logistic regression, artificial neural networks, and random forests. Five-fold cross-validation was performed. Model performance was evaluated based on area under the receiver operating characteristic curve (AUC), accuracy, precision, and recall.

Results: The mean (standard deviation) age of the AoU cohort was 69.1 (10.5) years, with 57.3% women and 33.5% black, significantly exceeding representation in the single-center cohort (P = .04 and P < .001, respectively). Of 1,231 participants, 286 (23.2%) needed glaucoma surgery. When applying the single-center model to AoU data, accuracy was 0.69 and AUC was only 0.49. Using AoU data to train new models resulted in superior performance: AUCs ranged from 0.80 (logistic regression) to 0.99 (random forests).

Conclusions: Models trained with national AoU data achieved superior performance compared with using single-center data. Although AoU does not currently include ophthalmic imaging, it offers several strengths over similar big-data sources such as claims data. AoU is a promising new data source for ophthalmic research.
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http://dx.doi.org/10.1016/j.ajo.2021.01.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184631PMC
July 2021

Effects of Prolonged Dual Antiplatelet Therapy in ST-Segment Elevation vs. Non-ST-Segment Elevation Myocardial Infarction.

Circ J 2021 May 9;85(6):817-825. Epub 2021 Jan 9.

Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine.

Background: The benefits and risks of prolonged dual antiplatelet therapy (DAPT) have not been studied extensively across a broad spectrum of acute coronary syndromes. In this study we investigated whether treatment effects of prolonged DAPT were consistent in patients presenting with ST-segment elevation myocardial infarction (STEMI) vs. non-STEMI (NSTEMI).Methods and Results:As a post hoc analysis of the SMART-DATE trial, effects of ≥12 vs. 6 months DAPT were compared among 1,023 patients presenting with STEMI and 853 NSTEMI patients. The primary outcome was a composite of recurrent myocardial infarction (MI) or stent thrombosis at 18 months after the index procedure. Compared with the 6-month DAPT group, the rate of the composite endpoint was significantly lower in the ≥12-month DAPT group (1.2% vs. 3.8%; hazard ratio [HR] 0.31, 95% confidence interval [CI] 0.12-0.77; P=0.012). The treatment effect of ≥12- vs. 6-month DAPT on the composite endpoint was consistent among NSTEMI patients (0.2% vs. 1.2%, respectively; HR 0.20, 95% CI 0.02-1.70; P=0.140; P=0.718). In addition, ≥12-month DAPT increased Bleeding Academic Research Consortium (BARC) Type 2-5 bleeding among both STEMI (4.4% vs. 2.0%; HR 2.18, 95% CI 1.03-4.60; P=0.041) and NSTEMI (5.1% vs. 2.2%; HR 2.37, 95% CI 1.08-5.17; P=0.031; P=0.885) patients.

Conclusions: Compared with 6-month DAPT, ≥12-month DAPT reduced recurrent MI or stent thrombosis regardless of the type of MI at presentation.
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http://dx.doi.org/10.1253/circj.CJ-20-0704DOI Listing
May 2021

Simultaneous Measurement of Liquid Level and Temperature Using In-Fiber Grating-Based Mach-Zehnder Interferometer and Faraday Rotator Mirror.

J Nanosci Nanotechnol 2021 03;21(3):2024-2031

Interdisciplinary Program of Biomedical Mechanical & Electrical Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Korea.

Here we propose an optical fiber sensor capable of simultaneous measurement of liquid level and temperature by utilizing cascaded long-period fiber gratings (LPFGs) inscribed on high-birefringence fiber (HBF) and a Faraday rotator mirror (FRM). Due to the in-fiber Mach-Zehnder interference and birefringence of the HBF, these cascaded LPFGs have polarization-dependent discrete interference spectra, each of which is created within one of the two different attenuation bands obtained in the two orthogonal input polarization states, e.g., linear horizontal polarization (LHP) and linear vertical polarization (LVP). The minimum transmittance dip was selected as a sensor indicator for each interference spectrum obtained for LHP or LVP input signal. To monitor these indicator dips associated with LHP and LVP, referred to as the IDH and IDV, respectively, with one spectral scanning, an FRM was connected to the end of the cascaded LPFGs. Both the IDH and IDV spectrally shifted according to liquid-level or temperature changes and showed very linear responses to them with adjusted ₂ values greater than 0.997. The liquid-level sensitivities of the IDH and IDV were measured as approximately -37.29 and -121.08 pm/mm in a liquid-level range of 0 to 55 mm, respectively. The temperature sensitivities of the IDH and IDV were measured as ˜28.79 and ˜218.21 pm/°C in a temperature range of 30 to 60 °C, respectively. Owing to their linear and independent responses to liquid level and temperature, our sensor can perform temperature-independent liquid-level measurement using their pre-determined liquid-level and temperature sensitivities, even if both liquid level and temperature change simultaneously.
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http://dx.doi.org/10.1166/jnn.2021.18915DOI Listing
March 2021

Bend-Insensitive Discrimination of Strain and Temperature Based on Fiber Transmission Grating Inscribed on High Birefringence Photonic Crystal Fiber.

J Nanosci Nanotechnol 2021 Mar;21(3):1948-1954

School of Electrical Engineering, Pukyong National University, Busan 48513, Korea.

In this paper, we propose a bend-insensitive optical fiber sensor capable of separately measuring strain and temperature by incorporating a fiber transmission grating (FTG) inscribed on high birefringence photonic crystal fiber (HBPCF) with a CO laser. The FTG was fabricated by exposing unjacketed HBPCF to CO laser pulses using the line-by-line technique. The FTG inscribed on HBPCF, referred to as the HBPC-FTG, has two resonance dips with different wavelengths depending on input polarization. These two resonance dips were utilized as sensor indicator dips denoted by a shorter wavelength dip (SD) and a longer wavelength dip (LD). The strain and temperature responses of the SD and LD were investigated in a strain range of 0 to 3105 μ and a temperature range of 30 to 85 °C, respectively. The measured strain sensitivities of the SD and LD at room temperature (25 °C) were approximately -0.46 and -0.58 pm/μ, respectively. Similarly, the measured temperature sensitivities of the SD and LD without applied strain (0 μ) were ˜5.99 and ˜9.89 pm/°C, respectively. Owing to their linear and independent responses to strain and temperature, strain and temperature changes applied to the HBPC-FTG can be simultaneously estimated from the measured wavelength shifts of the two indicator dips (i.e., SD and LD) using their predetermined strain and temperature sensitivities. Moreover, bend-induced spectral variations of the SD and LD were also examined in a curvature range of 0-4.705 m, and it was observed that both dips showed little wavelength shift due to applied bending. Thus, it is concluded from the experimental results that the fabricated HBPC-FTG can be employed as a cost-effective sensor head for bend-insensitive discrimination of strain and temperature.
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http://dx.doi.org/10.1166/jnn.2021.18895DOI Listing
March 2021

Strain-Insensitive Simultaneous Measurement of Bending and Temperature Using Long-Period Fiber Grating Inscribed on Double-Clad Fiber with CO₂ Laser.

J Nanosci Nanotechnol 2021 03;21(3):1883-1889

Interdisciplinary Program of Biomedical Mechanical & Electrical Engineering, Pukyong National University, Busan 48513, Korea.

Here we report an optical fiber sensor capable of performing strain-insensitive simultaneous measurement of bending and temperature using a long-period fiber grating (LPFG) inscribed on doubleclad fiber (DCF) with a CO₂ laser at ˜10.6 μm. The LPFG inscribed on DCF, referred to as a DC-LPFG, was fabricated by scanning CO₂ laser pulses on an unjacketed DCF with a specific period. Due to co-directional mode coupling, the fabricated DC-LPFG has discrete attenuation bands widely distributed over hundreds of nanometers. Among these wavelength-dependent loss dips, adjacent two dips with different resonance wavelengths were selected as sensor indicators for the measurement of bending and temperature. For these two indicator dips designated as dips and , their bending and temperature responses were investigated in a curvature range of 4.90 to 21.91 m and a temperature range of 30 to 110 °C. With increasing bending applied to the DC-LPFG at room temperature, dips and showed different blue shifts. The bending sensitivities of dips and were measured to be approximately -0.77 and 0.51 nm/m, respectively. Unlike the bending response, they showed red shifts of different amounts with increasing ambient temperature, while the sensor head (i.e., the DC-LPFG) remained straight without any applied bending. The temperature sensitivities of dips and were measured to be ˜0.094 and ˜0.078 nm/°C, respectively. Owing to their linear and independent responses to bending and temperature, bending and temperature changes applied to the DC-LPFG could be simultaneously estimated from the measured wavelength shifts of the two indicator dips using their pre-determined bending and temperature sensitivities. Moreover, in a strain range of 0 to 2200 με (step: 200 με), strain-induced spectral variations of dips and were also measured, and the strain sensitivities of dips and were evaluated as approximately -0.028 and -0.013 pm/με, respectively. These strain-induced wavelength shifts were so small that they had little effect on the measurement results of bending and temperature. Thus, it is concluded that the fabricated DC-LPFG can be employed as a cost-effective sensor head for strain-insensitive separate measurement of bending and temperature.
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http://dx.doi.org/10.1166/jnn.2021.18908DOI Listing
March 2021

Reversible 100 mA Current Switching in a VO₂/Al₂O₃-Based Two-Terminal Device Using Focused Far-Infrared Laser Pulses.

J Nanosci Nanotechnol 2021 Mar;21(3):1862-1868

School of Electrical Engineering, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 48513, Korea.

In this study, we implemented reversible current switching (RCS) of 100 mA in a two-terminal device based on a vanadium dioxide (VO₂) thin film, which could be controlled by far-infrared (FIR) laser pulses. The VO₂ thin films used for fabrication of two-terminal devices were grown on sapphire (Al₂O₃) substrates using a pulsed laser deposition method. An optimal deposition condition was determined by analyzing the resistance-temperature curves of deposited VO₂ thin films and the current-voltage characteristics of two-terminal devices based on these films, which were suggested in our previous works. The film surface of the VO₂-based device was directly irradiated using focused CO₂ laser pulses, and the insulator-metal transition or metal-insulator transition of the VO₂ thin film could be triggered depending on laser irradiation. Consequently, RCS of up to 100 mA could be accomplished. This on-state current is close to the upper limit of the current flowing through our VO₂ device. The switching contrast, defined as the ratio between on-state and off-state currents, was evaluated and found to be ˜11,962. The average rising and falling times of the switched current were found to be ˜29.2 and ˜71.7 ms, respectively. In comparison with our previous work, the improved heat dissipation structure and the high-quality thin film could maintain the switching contrast at a similar level, although the on-state current was increased by about two times.
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http://dx.doi.org/10.1166/jnn.2021.18905DOI Listing
March 2021

Pre-operative anaemia and myocardial injury after noncardiac surgery: A retrospective study.

Eur J Anaesthesiol 2021 06;38(6):582-590

From the Department of Anesthesiology and Pain Medicine (J-HK, JP, JHL, JJM, ARO, WS), Division of Cardiology, Department of Medicine, Heart Vascular Stroke Institute (S-HL, CWH, J-hC, S-CL, H-CG), Center for Health Promotion (KY), Department of Emergency Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine (J-hC), Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center (KK, JA), Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea (KK).

Background: Pre-operative anaemia is associated with adverse outcomes of noncardiac surgery, but its association with myocardial injury after noncardiac surgery (MINS) has not been fully investigated.

Objective: The association between pre-operative anaemia and MINS.

Design: A single-centre retrospective cohort study.

Setting: Tertiary care referral centre.

Patients: Patients with measured cardiac troponin (cTn) I levels after noncardiac surgery.

Interventions: Patients were separated according to pre-operative anaemia (haemoglobin <13 g dl-1 in men and <12 g dl-1 in women). Anaemia was further stratified into mild and moderate-to-severe at a haemoglobin level threshold of 11 g dl-1.

Main Outcome Measures: The primary outcome was MINS, defined as a peak cTn I level more than 99th percentile of the upper reference limit within 30 postoperative days.

Results: Data from a total of 35 170 patients were collected, including 22 062 (62.7%) patients in the normal group and 13 108 (37.3%) in the anaemia group. After propensity score matching, 11919 sets of patients were generated, and the incidence of MINS was significantly associated with anaemia [14.5 vs. 21.0%, odds ratio (OR) 1.57, 95% confidence interval (CI) 1.47 to 1.68, P < 0.001]. For the entire population, multivariable analysis showed a graded association between anaemia severity and MINS (OR 1.32, 95% CI 1.22 to 1.43, P < 0.001 for mild anaemia and OR 1.80, 95% CI 1.66 to 1.94, P < 0.001 for moderate-to-severe anaemia compared with the normal group) and a significantly higher incidence of MINS for moderate-to-severe anaemia than mild anaemia (18.6 vs. 28.6%, OR 1.37, 95% CI 1.25 to 1.50, P < 0.001). The estimated threshold for pre-operative haemoglobin associated with MINS was 12.2 g dl-1, with an area under the curve of 0.622.

Conclusions: Pre-operative anaemia was independently associated with MINS, suggesting that MINS may be related to the association between anaemia and postoperative mortality.

Trial Registration: SMC 2019-08-048.
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http://dx.doi.org/10.1097/EJA.0000000000001421DOI Listing
June 2021

Elevated high-sensitivity C-reactive protein concentrations may be associated with increased postdischarge mortality in patients with myocardial injury after noncardiac surgery: A retrospective observational study.

Eur J Anaesthesiol 2021 Mar;38(Suppl 1):S33-S40

From the Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (ARO, JP, JHL, JJM, J-hK, J-hC), Division of Cardiology, Department of Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (S-HL, JK, CWH, J-hC,S-CL, H-CG), Department of Emergency Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J-hC), Centers for Health Promotion, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (KY).

Background: Myocardial injury after noncardiac surgery (MINS) is one of the most common cardiovascular complications associated with mortality and morbidity during the first 2 years after surgery. However, the relevant variables associated with mortality after discharge in patients with MINS have not been fully investigated.

Objectives: This study aimed to evaluate the association between persistent inflammation detected by high-sensitivity C-reactive protein (hsCRP) at discharge and postdischarge mortality after MINS.

Design: Retrospective observational analysis of acquired data from Samsung Medical Center Troponin in Noncardiac Operation (SMC-TINCO) registry.

Setting: A tertiary hospital from January 2010 to June 2019.

Patients: Patients who were discharged alive after a diagnosis of MINS.

Main Outcome Measures: The primary endpoint was postdischarge 1-year mortality, and 30-day mortality and the mortality from 30 days to 1 year was also compared.

Results: Data from a total of 4545 adult patients were divided into two groups according to hsCRP concentration at discharge. There were 757 (16.7%) patients in the normal hsCRP group and 3788 (83.3%) patients in the elevated hsCRP group. After inverse probability weighting, 1-year mortality was significantly higher in the elevated group than the normal group (hazard ratio 1.93, 95% CI 1.45 to 2.57, P  < 0.001). Thirty-day mortality and the mortality from 30 days to 1 year were also increased in the elevated group.

Conclusion: In patients with MINS, an elevated hsCRP concentration at discharge appeared to be associated with increased mortality. Further research is needed to determine whether controlling inflammation can be helpful in reducing mortality.
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http://dx.doi.org/10.1097/EJA.0000000000001409DOI Listing
March 2021