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Step junctions are often present in layered materials, i.e. where single-layer regions meet multilayer regions, yet their effect on thermal transport is not understood to date. Here, we measure heat flow across graphene junctions (GJs) from monolayer-to-bilayer graphene, as well as bilayer to four-layer graphene for the first time, in both heat flow directions. The thermal conductance of the monolayer-bilayer GJ ranges from ∼0.5 to 9.1 × 108 W m-2 K-1 between 50 K to 300 K. Atomistic simulations of such a GJ device reveal that graphene layers are relatively decoupled, and the low thermal conductance of the device is determined by the resistance between the two distinct graphene layers. In these conditions the junction plays a negligible effect. To prove that the decoupling between layers controls thermal transport in the junction, the heat flow in both directions was measured, showing no evidence of thermal asymmetry or rectification, within experimental error bars. For large-area graphene applications, this signifies that small bilayer (or multilayer) islands have little or no contribution to overall thermal transport.

Purpose: The study purpose was to prospectively determine the accuracy of contrast-enhanced CT in diagnosing fatty liver using same-day biopsy as the reference standard.Materials and Methods: One hundred seventy-nine potential living liver donors underwent unenhanced and portal-phase contrast-enhanced hepatic CT and subsequent liver biopsy on the same day. Attenuation difference between the liver and the spleen on unenhanced (( pre ) L-S) and contrast-enhanced (( post ) L-S) images and blood-subtracted hepatic attenuation on contrast-enhanced images (( post ) L-B), calculated by [L - 0.3 x (0.75 x P + 0.25 x A)]/0.7 where L, P and A represent the attenuation of the liver, main portal vein and abdominal aorta, respectively, were obtained. The accuracy of these indices in diagnosing fatty liver according to various threshold levels, 5%-30% histological steatosis in increments of 5%, was compared using ROC analysis.Results: The area under the ROC curve for ( pre ) L-S, ( post ) L-S and ( post ) L-B was 0.663-0.918, 0.712-0.847 and 0.821-0.923, respectively, depending on the threshold levels of hepatic steatosis. The accuracy of ( pre ) L-S and ( post ) L-S did not differ (P >or= 0.054), despite a trend towards a lower accuracy with ( post ) L-S. ( post ) L-B yielded higher accuracy than ( pre ) L-S at threshold levels of 5% and 10% (P or= 0.144).Conclusion: Portal-phase contrast-enhanced CT has a similar, or even greater, accuracy than unenhanced CT in diagnosing fatty liver. [ABSTRACT FROM AUTHOR]

Background: Bacteroides fragilis group (BFG) isolates are the most frequently isolated gram-negative anaerobic bacteria and exhibit higher levels of antimicrobial resistance than other anaerobic bacteria. Reliable susceptibility testing is needed because of reports of resistance to the most active antibiotics. Recently, the European Committee on Antimicrobial Susceptibility Testing (EUCAST) introduced disk zone diameter breakpoints. We evaluated the disk diffusion test (DDT) for susceptibility testing of BFG isolates compared with the agar dilution method., Methods: In total, 150 BFG isolates were collected from three institutes in Korea. The agar dilution method was conducted according to the CLSI guidelines. DDT was performed following the EUCAST guideline. Fastidious anaerobe agar supplemented with 5% defibrinated horse blood was used as the culture medium. Nine antimicrobials were evaluated: penicillin, cefoxitin, cefotetan, imipenem, meropenem, piperacillin-tazobactam, clindamycin, moxifloxacin, and metronidazole., Results: The categorical agreement (CA) between the two methods was >90.0% for imipenem, meropenem, clindamycin, and metronidazole. However, the CA for piperacillintazobactam was low, at 83.2%. Major errors were found: 5.4% for imipenem, 7.4% for meropenem, and 12.8% for piperacillin-tazobactam. All minor errors were <10%. We propose using the area of technical uncertainty (ATU) zone-overlapping area for susceptible and resistant strains to reduce errors in the DDT. Outside the ATU, the CAs of cefoxitin, cefotetan, and piperacillin-tazobactam were >90.0%, whereas that of moxifloxacin was increased to 88.5%., Conclusions: The DDT can be a useful alternative antimicrobial susceptibility test for BFG isolates when using the ATU zone to reduce errors.

Rapid detection of SARS-CoV-2 is essential for clinical management in the emergency department during the COVID-19 pandemic. We evaluated the clinical performance of the recently developed cartridge-based rapid RT-PCR assay (STANDARD M10 SARS-CoV-2) in patients visiting the emergency department from July 2022 to January 2023, which was when the Omicron BA.5 sublineage was predominant in Korea. A total of 534 specimens were subjected to the STANDARD M10 and standard RT-PCR (Allplex SARS-CoV-2) assays. The overall, positive, and negative percent agreements between these two assays were 99.6%, 100%, and 99.6%, respectively. The results showed that compared with the established RT-PCR assay, the STANDARD M10 SARS-CoV-2 assay is a reliable and useful tool for SARS-CoV-2 detection during the study period. The new rapid RT-PCR will expand the diversity in rapid diagnostics and can help resolve the global imbalance associated with the supply of diagnostic resources., 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 © 2024 Elsevier Inc. All rights reserved.)

Introduction: The diagnosis of myocardial infarction (MI) needs to be swift and accurate, but definitively diagnosing it based on the first test encountered in clinical practice, the electrocardiogram (ECG), is not an easy task. The purpose of the study was to develop a deep learning (DL) algorithm using multitask learning method to differentiate patients experiencing MI from those without coronary artery disease using image-based ECG data., Methods: A DL model was developed based on 11,227 ECG images. We developed a new ECG interpretation algorithm through signal-guided multitask learning, building on a previously published single-task algorithm. The utility of this model was evaluated by testing 51 physicians in interpreting ECGs with and without the assistance of the DL model., Results: The proposed model demonstrated superior performance, achieving 90.56% accuracy, 83.82% sensitivity, 93.02% specificity, 81.44% precision, and an F1 score of 82.61% in discriminating MI ECG. Overall, the median accuracy of ECG interpretation improved from 62% to 68% with the DL algorithm. Trainees and specialists in internal medicine experienced significant accuracy increases (60-66% for trainees, 72-80% for specialists). In the MI group, NSTEMI accuracy was notably lower than STEMI (33% vs. 80%, p < 0.001), but the DL algorithm improved interpretative capabilities in both NSTEMI and STEMI., Conclusions: Signal-guided multitask DL algorithm demonstrated superior performance compared with previous single-task algorithm. The DL algorithm supports the physicians' decision discriminating MI ECGs from non-MI ECGs. The improvement was consistent in subgroups of STEMI and NSTEMI., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

The precise characterization and control of single-electron wave functions emitted from a single-electron source are essential for advancing electron quantum optics. Here, we introduce a method for tailoring a single-electron emission distribution using energy filtering, enabling selective control of the distribution under various energy barrier conditions of the filter. The tailored electron is studied by reconstructing its Wigner distribution in the time-energy phase space using the continuous-variable tomography method. Our results reveal that the filtering cuts the portion of the distribution below the energy-barrier height of the filter in the time-energy space. While the filtering is demonstrated in a classical regime of the emitted electrons, we expect that this study significantly contributes to the design and implementation of advanced experiments toward quantum information processing based on single electrons.

Background: There is limited research on the intra-individual efficacy of ventricular pacing minimization algorithms developed by Biotronik-the Ventricular Pace Suppression algorithm (VpS) and the Intrinsic Rhythm Support plus algorithm (IRSplus) (BIOTRONIK SE & Co. KG, Berlin, Germany). We performed a randomized pilot trial that evaluated the efficacy of two algorithms in patients with symptomatic sinus node dysfunction (SND) who received a dual-chamber pacemaker., Methods: The trial was conducted in 11 tertiary hospitals in South Korea. The patients were randomized to either the VpS or IRSplus algorithm group after a 3-month period of fixed atrioventricular (AV) delay. The primary outcome was the ventricular pacing percentage (Vp%) at each follow-up visit. The secondary outcomes were the occurrence of heart failure (HF) and atrial fibrillation (AF) during the study period., Results: Data from 131 patients were analyzed. Initially, their average Vp% over 3 months with a fixed AV interval was 14.1 ± 19.4%. Patients were randomly assigned to VpS and IRSplus groups, with 66 and 65 in each. Algorithms reduced average Vp% to 4.0 ± 11.3% at 9 months and 6.7 ± 14.9% at 15 months. These algorithms were more effective for patients with paced AV delay (PAVD) ≤300 ms compared to those with PAVD >300 ms. Both algorithms were equally effective in reducing Vp%. Clinical AF or HF hospitalization was not observed during the study period., Conclusion: The VpS and IRSplus algorithms are effective and safe in minimizing unnecessary ventricular pacing in patients with SND., Competing Interests: Authors declare no conflict of interests for this article., (© 2024 The Author(s). Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of Japanese Heart Rhythm Society.)

Imaging modalities for percutaneous coronary intervention (PCI), such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT), have increased in the current PCI era. However, their clinical benefits in acute myocardial infarction (AMI) have not been fully elucidated. This study investigated the long-term outcomes of image-guided PCI in patients with AMI using data from the Korean Acute Myocardial Infarction Registry. A total of 9,271 patients with AMI, who underwent PCI with second-generation drug-eluting stents between November 2011 and December 2015, were retrospectively examined, and target lesion failure (TLF) at 3 years (defined as the composite of cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization) was evaluated. From the registry, 2,134 patients (23.0%) underwent image-guided PCI (IVUS-guided: n = 1,919 [20.6%]; OCT-guided: n = 215 patients [2.3%]). Based on propensity score matching, image-guided PCI was associated with a significant reduction in TLF (hazard ratio: 0.76; 95% confidence interval: 0.59-0.98, p = 0.035). In addition, the TLF incidence in the OCT-guided PCI group was comparable to that in the IVUS-guided PCI group (5.3% vs 4.7%, p = 0.903). Image-guided PCI, including IVUS and OCT, is associated with favorable clinical outcomes in patients with AMI at 3 years post-intervention. Additionally, OCT-guided PCI is not inferior to IVUS-guided PCI in patients with AMI., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kwon 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.)

Developmental dysplasia of the hip (DDH) is a broad-spectrum disorder. Early diagnosis and treatment are important for improved prognosis and a lower risk of long-term complications. Selecting high-risk infants is important for the early diagnosis of DDH using ultrasonography; however, there are no standard international guidelines. This study aimed to identify the usefulness of universal ultrasound before hospital discharge in breech-born neonates and proposes selective ultrasound for high-risk patients. A retrospective chart review was conducted to identify breech-born neonates who underwent hip ultrasonography before discharge for the detection of DDH between 2019 and 2023. Patients were categorized into DDH and non-DDH groups according to the ultrasound results. We compared sex, gestational age, birth weight, first-born status, twin pregnancy, associated anomalies, presence of symptoms, physical examination results, and timing of the first hip ultrasound. The medical records of the mothers were reviewed to identify the amount of amniotic fluid and duration of breech presentation. This study included 102 patients, of whom 62 and 40 were assigned to the non-DDH and DDH groups, respectively. Congenital anomalies, positive symptoms, and positive physical examination results were significant risk factors. However, female sex, first-born status, and oligohydramnios were not statistically significant. The duration of breech presentation during pregnancy was not significant. Additionally, the risk of Pavlik harnesses was higher in patients who underwent a positive physical examination. Universal ultrasonography before discharge is not recommended for the early diagnosis of DDH in all breech-born neonates because of the high rate of overdiagnosis. We recommend that ultrasonography be performed in patients with congenital anomalies, except for foot problems, or in those with a positive physical examination conducted by trained specialists., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Life satisfaction among Korean students is declining substantially, and multifaceted improvement efforts are required., Methods: We analyzed longitudinal change trajectories for exercise, grit, and life satisfaction levels among Korean adolescents using latent growth modeling with longitudinal data from the Korean Children and Youth Panel Surveys of 2,142 students (male: 1,070, female: 1,072) from sixth grade (2020) through eighth grade (2022)., Results: The model, which tracked linear changes in the students' exercise, grit, and life satisfaction, showed consistent declines over three school years for all variables. We also identified a longitudinal causal relationship among exercise, grit, and life satisfaction. A higher grit intercept was associated with higher intercept for-and a partial mediating effect between-exercise and life satisfaction. The grit slope was positively related to the life satisfaction slope, and both the intercept and exercise slope had positive effects on life satisfaction. Moreover, grit had a longitudinal mediating effect between exercise and life satisfaction., Conclusions: We discuss the longitudinal change trajectories of exercise, grit, and life satisfaction, the causal and mediating effects among them, and the implications of the findings. These findings bolster our understanding of Korean adolescents' life satisfaction and have practical significance for designing programs to improve their quality of life., (© 2024. The Author(s).)

In recent years, the development and use of various devices for the screening of atrial fibrillation (AF) have significantly increased. Such devices include 12-lead electrocardiogram (ECG), photoplethysmography systems, and single-lead ECG and ECG patches. This review outlines several studies that have focused on the feasibility and efficacy of such devices for AF screening, and summarizes the risks and benefits involved in the initiation of anticoagulant therapy after early detection of AF. We also describe several ongoing trials on unresolved issues associated with AF screening. Overall, this review provides a comprehensive summary of the current state of AF screening and its implications for patient care.

Background: Boston Scientific INGEVITY+ pacing lead (Boston Scientific, Marlborough, MA, USA) has been upgraded to INGEVITY. The performance of the INGEVITY+ pacing lead has not yet been reported. This study aimed to evaluate the short- and long-term safety, effectiveness, and handling experience of INGEVITY+ leads., Methods: Consecutive patients were included from 9 institutions in Korea, where 400 leads (200 right ventricular active fixation leads and 200 right atrial active fixation leads) were implanted or attempted in 200 subjects., Results: During the implantation, only one patient required a lead change because of lead screw failure. The handling questionnaires of the lead received very positive feedback with 88% of operators agreeing that it is easy for leads to pass through small vessels or vessels with multiple leads. At the 3-month follow-up, 95.7% of RA leads and 99.5% of RV leads had pacing thresholds less than 1.5 V. A total of 92.4% of atrial leads had amplitudes greater than 1.5 mV, and 96.5% of ventricular leads had sensing amplitudes greater than 5 mV at 3 months. A total of 99.8% had impedances between 300 and 1,300 ohms. The lead-related complication-free rate for all leads during follow-up was 100%, and the overall rates of lead dislodgment, perforation, and pericardial effusion were all 0.0%., Conclusions: The INGEVITY+ pacing lead exhibited exceptional clinical performance, with a high complication-free rate throughout the 3-month follow-up period. In addition, the lead displayed excellent electrical characteristics, and the lead-handling experience was reported to be very good., Competing Interests: BJ has provided speaking engagements for Bayer, BMS/Pfizer, Medtronic, and Daiichi-Sankyo and has received research grants from Medtronic, Boston and Abbott, Korea. No personal or direct payments were received., (Copyright © 2024 Boyoung Joung et al.)

In emergency departments, rapid screening of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was important for arranging limited isolation resources and patient care during the coronavirus disease 2019 (COVID-19) pandemic. STANDARD M10 SARS-CoV-2 (SD Biosensor) is a recently developed cartridge-based RT-PCR that provides a turnaround time of 1 h, which is shorter than that for conventional RT-PCR. This study evaluated the clinical performance of STANDARD M10 in patients visiting an emergency department. From March to June 2022, two specimens were collected from patients visiting an emergency department. Each specimen comprised one nasopharyngeal and one oropharyngeal swab. Respective specimens underwent rapid RT-PCR using STANDARD M10 and conventional RT-PCR using Allplex SARS-CoV-2 (Seegene). When discordant results occurred, specimens undergoing the STANDARD M10 were retested with the Allplex to exclude specimen variations. Retest results replaced initial results of the Allplex. Clinical performance of STANDARD M10 was compared with Allplex. The study enrolled 1971 patients. COVID-19 prevalence was 6.2% based on the Allplex. Compared with the Allplex, overall agreement, positive percent agreement, and negative percent agreement of STANDARD M10 were 99.5% (95% CI: 99.1%-99.8%), 95.9% (95% CI: 90.8%-98.3%), and 99.8% (95% CI: 99.4%-99.9%), respectively. Nine discordant results were all positive on droplet digital PCR, except for one specimen that was positive with STANDARD M10. The STANDARD M10 showed reliable diagnostic performance for detecting SARS-CoV-2 from patients visiting in emergency departments and is a useful tool in emergency healthcare systems because of its easy-to-use cartridge-based assay and short resulting time for detecting SARS-CoV-2., (© 2023 Wiley Periodicals LLC.)

Background: This study analyzed physical health awareness, self-esteem, and depression as mediation factors in the effect of exercise on school life satisfaction. It compared these between Korean children and adolescents., Methods: Based on the 2020 Survey on the Human Rights of Children and Adolescents in Korea, data were extracted on 2,896 children in grades 4 to 6 and 5,727 adolescents in grades 7 to 12. A structural equation model was designed and multi-mediation analysis was conducted using phantom variables. To verify the differences between children and adolescents, latent means, path coefficients, and mediating effect confidence intervals were analyzed., Results: Structural modeling and bootstrapping revealed that the direct and indirect paths were significant in both groups ( P <0.01). Comparing the mean differences, children showed higher means than adolescents did in all variables. Among the direct paths, the paths of physical health awareness from exercise practice and school life satisfaction from physical health awareness were higher in adolescents ( P <0.01), and the path of school life satisfaction from exercise practice was higher in children ( P <0.01). The indirect paths showed that the mediating effect of health awareness between exercise and school life satisfaction was stronger among adolescents., Conclusion: Physical and mental health directly and indirectly affect school life satisfaction, with different patterns in children and adolescents. This study emphasizes the need for different strategies for children and adolescents who are experiencing physical and mental health problems and difficulties adjusting to school life., (Copyright© 2023 Bae. Published by Tehran University of Medical Sciences.)

Aims: The long-term effect of angiotensin receptor-neprilysin inhibitor (ARNI) remains uncertain in patients who have experienced improvements in left ventricular (LV) systolic function or significant LV reverse remodelling following a certain period of treatment. It is also unclear how ARNI performs in patients who have not shown these improvements. This study aimed to assess the impact of prolonged ARNI use compared with angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) in patients with and without significant treatment response after 1 year of heart failure (HF) treatment., Methods and Results: The present study enrolled patients with HF with reduced ejection fraction (HFrEF) who were treated with either ARNI or ACEIs/ARBs within 1 year of undergoing index echocardiography. After 1 year of treatment, patients were reclassified into the following groups: (i) patients with HF with improved ejection fraction and persistent HFrEF and (ii) patients with and without LV reverse remodelling based on the follow-up echocardiography. The effect of ARNI versus that of ACEIs/ARBs in each group was assessed from the time of categorizing into new groups using the composite event of all-cause mortality and HF hospitalization. A total of 671 patients with HFrEF (age, 66.4 ± 14.1 years; males, 66.8%) were included, and 133 (19.8%) composite events of death and rehospitalization for HF were observed during the follow-up (median follow-up, 44 [interquartile range, 34-51] months). ARNI had a significantly lower event rate than ACEIs/ARBs in patients with HF with improved ejection fraction (7.0% vs. 30.4%, P = 0.020) and those with persistent HFrEF (17.6% vs. 49.7%, P < 0.001). Irrespective of whether patients exhibited LV reverse remodelling (15.8% vs. 31.1%, P = 0.001) or not (15.0% vs. 54.9%, P < 0.001), ARNIs were associated with a significantly lower event rate than ACEIs/ARBs., Conclusions: Regardless of significant treatment response measured by either LVEF or LV reverse remodelling after 1 year of treatment, the extended utilization of ARNI demonstrated a more favourable prognosis than that of ACEIs/ARBs in patients with HFrEF., (© 2023 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Background: Positron emission tomography (PET) viability scan is used to determine whether patients with a myocardial scar on single-photon emission computed tomography (SPECT) may need revascularization. However, the clinical utility of revascularization decision-making guided by PET viability imaging has not been proven yet. The purpose of this study was to investigate the impact of PET to determine revascularization on clinical outcomes., Methods: Between September 2012 and May 2021, 53 patients (37 males; mean age = 64 ± 11 years) with a myocardial scar on MIBI SPECT who underwent PET viability test were analyzed in this study. The primary outcome was a temporal change in echocardiographic findings. The secondary outcome was all-cause mortality., Results: Viable myocardium was presented by PET imaging in 29 (54.7%) patients. Revascularization was performed in 26 (49.1%) patients, including 18 (34.0%) with percutaneous coronary intervention (PCI) and 8 (15.1%) with coronary artery bypass grafting. There were significant improvements in echocardiographic findings in the revascularization group and the viable myocardium group. All-cause mortality was significantly lower in the revascularization group than in the medical therapy-alone group (19.2% vs. 44.4%, log-rank P = 0.002) irrespective of viable (21.4% vs. 46.7%, log-rank P = 0.025) or non-viable myocardium (16.7% vs. 41.7%, log-rank P = 0.046). All-cause mortality was significantly lower in the PCI group than in the medical therapy-alone group (11.1% vs. 44.4%, log-rank P < 0.001)., Conclusion: Revascularization improved left ventricular systolic function and survival of patients with a myocardial scar on SPECT scans, irrespective of myocardial viability on PET scans., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2023 The Korean Academy of Medical Sciences.)

Film-type shape-configurable speakers with tunable sound directivity are in high demand for wearable electronics. Flexible, thin thermoacoustic (TA) loudspeakers-which are free from bulky vibrating diaphragms-show promise in this regard. However, configuring thin TA loudspeakers into arbitrary shapes is challenging because of their low sound pressure level (SPL) under mechanical deformations and low conformability to other surfaces. By carefully controlling the heat capacity per unit area and thermal effusivity of an MXene conductor and substrates, respectively, it fabricates an ultrathin MXene-based TA loudspeaker exhibiting high SPL output (74.5 dB at 15 kHz) and stable sound performance for 14 days. Loudspeakers with the parylene substrate, whose thickness is less than the thermal penetration depth, generated bidirectional and deformation-independent sound in bent, twisted, cylindrical, and stretched-kirigami configurations. Furthermore, it constructs parabolic and spherical versions of ultrathin, large-area (20 cm × 20 cm) MXene-based TA loudspeakers, which display sound-focusing and 3D omnidirectional-sound-generating attributes, respectively., (© 2023 Wiley-VCH GmbH.)

Background: Recently, panel-based molecular diagnostics for the simultaneous detection of respiratory viruses and bacteria in nasopharyngeal swab (NPS) specimens have been highlighted. We identified the distribution of bacterial species in NPS specimens collected from pediatric and adult patients by employing RT-PCR (Allplex respiratory panel 4, RP4, Seegene) to estimate its applicability in a panel-based assay for detecting respiratory viruses. Methods: We used 271 and 173 NPS specimens from pediatric and adult patients, respectively. The results of the Allplex RP4 panel using NPS (NPS-RP4) from adult patients were compared with those of the Seeplex PneumoBacter ACE Detection assay (Seegene), which used sputum for testing (sputum-Seeplex). Results: A total of 147 specimens (54.2%) were positive for the NPS-RP4 panel in pediatric patients. There were 94, 77, 10, 3, 3, and 2 specimens that were positive for Haemophilus influenzae (HI), Streptococcus pneumoniae (SP), Mycoplasma pneumoniae (MP), Chlamydia pneumoniae (CP), Bordetella pertussis (BP), and B. parapertussis (BPP), respectively. Among 173 adult patients, 39 specimens (22.5%) were positive in the NPS-RP4. Thirty specimens were positive for HI, and 13 were positive for SP. One specimen tested positive for both MP and Legionella pneumophila (LP). CP, BP, and BPP results were all negative. However, 126 specimens (72.8%) had positive results with sputum-Seeplex (99 SP, 59 HI, three LP, and two MP), and the overall percentage of agreement between the two assays was 39.3% in the adult patients. Conclusions: Bacterial species in NPS from more than half of pediatric patients were detected. Performing the Allplex RP4 assay with NPS revealed additional respiratory bacteria that are not detected in current clinical practices, which do not include bacterial testing, demanding the use of sputum specimens. However, the use of NPS showed low agreement with standard assays using sputum in adult patients. Thus, more research is needed to develop a reliable RT-PCR method using NPS specimens in adult patients.

We prospectively investigated whether the characteristics of lymphocyte subsets at diagnosis in acute myeloid leukemia (AML) patients are different from healthy controls and affect treatment outcomes. A total of 91 AML patients classified into 3 genetic risk subgroups (favorable/intermediate/poor) according to 2022 NCCN guidelines were enrolled. We measured lymphocyte subsets by flow cytometry with peripheral blood samples at diagnosis and compared results with healthy controls. Influences of lymphocyte subsets on complete remission (CR) rates and survivals were also evaluated. AML patients had significantly lower numbers and proportions of CD56 dim CD16 + natural killer (NK) cells, central memory T cells, and regulatory T cells than healthy controls. Higher proportion of helper/inducer T cells, CD4 + CD31 + naïve T cells, and decreased proportion of NK cells significantly increased CR rates in 65 non-promyelocytic leukemia patients (P = 0.034, 0.027, and 0.019, respectively), and it was also significant in multivariable analysis with age/risk adjusted (P = 0.014, 0.016, and 0.045, respectively). NK cells < 4.8% of lymphocytes demonstrated significantly shorter relapse free survivals (RFS) in both univariate and multivariate analyses with risk adjusted (P = 0.006 and 0.037, respectively). AML patients showed significant lower numbers of CD56 dim CD16 + NK cells, central memory T cells, and regulatory T cells than healthy controls at diagnosis. Higher proportion of helper/inducer T cells and CD4 + CD31 + naïve T cells and decreased proportion of NK cells at diagnosis were independent factor of increasing probability of CR, and proportion of NK cells < 4.8% at diagnosis had adverse impact in RFS., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Enterovirus infections frequently occur in children worldwide. Molecular assays are widely used to detect enterovirus. Nasopharyngeal swabs (NPS) and throat swabs (TS) are common specimen types used in clinical practice. Here, the reliability of TS for detecting enterovirus in pediatric patients was compared with that of NPS using real-time reverse transcription polymerase chain reaction (RT-rPCR)., Methods: Results obtained using the Allplex Respiratory Panel 2 (Seegene, Korea) for NPS (NPS-RP) and Accu-Power EV Real-time RT-PCR (Bioneer, Korea) for TS (TS-EV), which were performed simultaneously between September 2017 to March 2020, were initially compared. Cross examination (Allplex Respiratory Panel 2 assay using TS and AccuPower EV assay with NPS) was performed for specimens collected between July 2019 to March 2020 to evaluate the performance of the enterovirus assays based on each specimen type., Results: Among the 742 case results of initial tests, 597 cases (80.5%) tested negative in both assays, and 91 cases (12.6%) tested positive in both assays. Fifty-four discrepant results were observed: 39 cases (5.3%) tested positive in TS-EV and negative in NPS-RP, and 15 cases (2.0%) tested positive in NPS-RP and negative in TS-EV. The overall percent agreement was 92.7%. In the 99 cases cross examined, overall percent agreements were 98.0%, 94.9%, 92.9%, and 89.9% for TS-EV vs. TS-RP, NPS-RP vs. NPS-EV, TS-EV vs. NPS-EV, and NPS-RP vs. TS-RP, respectively., Conclusions: TS yields a high agreement rate with NPS in detecting enterovirus, regardless of single-plex or multiplex RT-rPCR assays. Thus, TS could be a good alternative specimen in pediatric patients who are reluctant to NPS sampling.

The mechanism of premature ventricular complexes (PVC) occurring in the ventricular outflow tract (OT) is related to an intracellular calcium overload and delayed afterdepolarizations that lead to triggered activity. The guidelines recommend using beta-blockers and flecainide for idiopathic PVCs, but they also acknowledge the limited evidence supporting this recommendation. We conducted a multicenter, randomized, open-label pilot study comparing the effect of carvedilol and flecainide on OT PVC, which are widely used to treat this arrhythmia. Patients with a 24 h Holter recording a PVC burden ≥ 5%, which showed positive R waves in leads II, III, and aVF, and without structural heart disease were enrolled. They were randomly assigned to the carvedilol or flecainide group, and the maximum tolerated dose was administered for 12 weeks. A total of 103 participants completed the protocol: 51 with carvedilol and 52 with flecainide. After 12 weeks of treatment, the mean PVC burden significantly decreased in both groups: 20.3 ± 11.5 to 14.6 ± 10.8% with carvedilol ( p < 0.0001) and 17.1 ± 9.9 to 6.6 ± 9.9% with flecainide ( p < 0.0001). Both carvedilol and flecainide effectively suppressed OT PVCs in patients without structural heart disease, with flecainide showing a superior efficacy compared to carvedilol.

Background: The epidemiology of pathogenic bacteria varies according to the socioeconomic status and antimicrobial resistance status. However, longitudinal epidemiological studies to evaluate the changes in species distribution and antimicrobial susceptibility of pathogenic bacteria nationwide are lacking. We retrospectively investigated the nationwide trends in species distribution and antimicrobial susceptibility of pathogenic bacteria over the last 20 years in Korea., Methods: From 1997 to 2016, annual cumulative antimicrobial susceptibility and species distribution data were collected from 12 university hospitals in five provinces and four metropolitan cities in South Korea., Results: The prevalence of Staphylococcus aureus was the highest (13.1%) until 2012 but decreased to 10.3% in 2016, consistent with the decrease in oxacillin resistance from 76.1% in 2008 to 62.5% in 2016. While the cefotaxime resistance of Escherichia coli increased from 9.0% in 1997 to 34.2% in 2016, E. coli became the most common species since 2013, accounting for 14.5% of all isolates in 2016. Pseudomonas aeruginosa and Acinetobacter baumannii rose to third and fifth places in 2008 and 2010, respectively, while imipenem resistance increased from 13.9% to 30.8% and 0.7% to 73.5% during the study period, respectively. Streptococcus agalactiae became the most common pathogenic streptococcal species in 2016, as the prevalence of Streptococcus pneumoniae decreased since 2010. During the same period, pneumococcal penicillin susceptibility decreased to 79.0%, and levofloxacin susceptibility of S. agalactiae decreased to 77.1% in 2016., Conclusion: The epidemiology of pathogenic bacteria has changed significantly over the past 20 years according to trends in antimicrobial resistance in Korea. Efforts to confine antimicrobial resistance would change the epidemiology of pathogenic bacteria and, consequently, the diagnosis and treatment of infectious diseases., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2023 The Korean Academy of Medical Sciences.)

Background: Anticoagulant therapy has been important for stroke prevention in patients with atrial fibrillation (AF). However, it was not recommended due to its relatively higher risk of bleeding than its lower risk of stroke in patients with a CHA 2 DS 2 -VASc score of 0., Hypothesis: This study aimed to evaluate the predictors of stroke in AF patients with very low risk of stroke., Methods: Between 1990 and 2020, 542 patients with non-valvular AF (NVAF) with a CHA 2 DS 2 -VASc score of 0 followed up for at least 6 months were enrolled. Patients with only being woman as a risk factor were included as a CHA 2 DS 2 -VASc score of 0 in this study. The primary outcome was stroke or systemic embolism., Results: The primary outcome rate was 0.78%/year. In Cox hazard model, age of ≥50 years at diagnosis (hazard ratio [HR] 6.710, 95% confidence interval [CI] 1.811-24.860, p = .004), LVEDD of ≥46 mm (HR 4.513, 95% CI 1.038-19.626, p = .045), and non-paroxysmal AF (HR 5.575, 95% CI 1.621-19.175, p = .006) were identified as independent predictors of stroke or systemic embolism. Patients with all three independent predictors had a higher risk of stroke or systemic embolism (4.21%/year), whereas those without did not have a stroke or systemic embolism., Conclusion: The annual stroke or systemic embolism rate in NVAF patients with CHA 2 DS 2 -VASc score of 0 was 0.78%/year, and age at AF diagnosis, LVEDD, and non-paroxysmal AF were independent predictors of stroke or systemic embolism in patients considered to have a very low risk of stroke., (© 2023 The Authors. Annals of Noninvasive Electrocardiology published by Wiley Periodicals LLC.)

We investigated if elevated cardiac troponin I (cTnI) serum levels before non-cardiac surgery were predictors of postoperative cardiac events in patients with end stage renal disease (ESRD) undergoing dialysis. In total, 703 consecutive patients with ESRD undergoing dialysis who underwent non-cardiac surgery were enrolled. Preoperative cTnI serum levels were measured at least once in all patients. The primary endpoint was defined as a composite of cardiac death, myocardial infarction (MI), and pulmonary edema during hospitalization or within 30 days after surgery in patients with a hospitalization longer than 30 days after surgery. Postoperative cardiac events occurred in 48 (6.8%) out of 703 patients (cardiac death 1, MI 18, and pulmonary edema 33). Diabetes mellitus (DM), previous ischemic heart disease, and congestive heart failure were more common in patients with postoperative cardiac events. Peak cTnI serum levels were higher in patients with postoperative cardiac event (180 ± 420 ng/L vs. 80 ± 190 ng/L, p = 0.008), and also elevated peak cTnI levels > 45 ng/L were more common in patients with postoperative cardiac events (66.8% vs. 30.5%, p < 0.001). Multivariate logistic regression analysis showed that DM (odds ratio [OR]  2.509, 95% confidence interval [CI] 1.178-5.345, p = 0.017) and serum peak cTnI levels ≥ 45 ng/L (OR 3.167, 95% CI 1.557-6.444, p = 0.001) were independent predictors for the primary outcome of cardiac death/MI/pulmonary edema. Moreover, cTnI levels ≥ 45 ng/L had an incremental prognostic value to the revised cardiac risk index (RCRI) (Chi-square = 23, p < 0.001), and to the combined RCRI and left ventricular ejection fraction (Chi-square = 12, p = 0.001). Elevated preoperative cTnI levels are predictors of postoperative cardiac events including cardiac death, MI, and pulmonary edema in patients with ESRD undergoing non-cardiac surgery., (© 2022. The Author(s).)

Background: This study aimed to verify the effectiveness of a virtual reality-based physical education program on physical fitness among Korean elementary school students., Methods: The study, conducted at a public school in South Korea in the second semester of 2022, included experimental and control groups of 45 participants each (N=90). All participants underwent physical fitness tests before and after the experiment. The students assigned to the experimental group participated in the virtual reality-based physical education program three times a week for a total of 8 weeks (40 minutes per session), while those assigned to the control group did not participate in any exercise program. The effect size was confirmed using Cohen's d, and a two-way repeated measures analysis of variance was used to analyze changes in physical factors before and after the experiment for each group., Results: Among the male participants, we observed significant differences in overall health-related physical fitness, cardiorespiratory endurance, muscular strength and endurance, and power between the experimental and control groups ( P <0.05). Among the female participants, we observed significant differences in overall health-related physical fitness, cardiorespiratory endurance, flexibility, and muscular strength and endurance between the groups ( P <0.05)., Conclusion: Virtual reality-based physical education may help to improve indicators of physical fitness among elementary school students, especially among those who have experienced deterioration of physical fitness during the COVID-19 pandemic. Our results, therefore, highlight the need to establish virtual reality-based physical education facilities at the elementary school level in Korea., Competing Interests: Conflict of interest The authors declare that there is no conflict of interests., (Copyright © 2023 Bae. Published by Tehran University of Medical Sciences.)

Background: Early extubation success (ES) in preterm infants may reduce various mechanical ventilation-associated complications; however, extubation failure (EF) can cause adverse short- and long-term outcomes. Therefore, the present study aimed to identify differences in risk factors and clinical outcomes between ES and EF in very early preterm infants., Methods: This retrospective study was conducted between January 2017 and December 2021. Premature infants born at 32 weeks' gestational age in whom extubation had failed at least once were assigned to the EF group. Successfully extubated patients with a similar gestational age and birth weight as those in the EF group were assigned to the ES group. EF was defined as the need for re-intubation within 120 h of extubation. Various variables were compared between groups., Results: The EF rate in this study was 18.6% (24/129), and approximately 80% of patients with EF required re-intubation within 90.17 h. In the ES group, there was less use of inotropes within 7 days of life (12 [63.2%] vs. 22 [91.7%], p = 0.022), a lower respiratory severity score (RSS) at 1 and 4 weeks (1.72 vs. 2.5, p = 0.026; 1.73 vs. 2.92, p = 0.010), and a faster time to reach full feeding (18.7 vs. 29.7, p = 0.020). There was a higher severity of bronchopulmonary dysplasia BPD (3 [15.8%] vs. 14 [58.3%], p = 0.018), longer duration of oxygen supply (66.5 vs. 92.9, p = 0.042), and higher corrected age at discharge (39.6 vs. 42.5, p = 0.043) in the EF group. The cutoff value, sensitivity, and specificity of the respiratory severity score (RSS) at 1 week were 1.98, 0.71, and 0.42, respectively, and the cutoff value, sensitivity, and specificity of RSS at 4 weeks were 2.22, 0.67, and 0.47, respectively., Conclusions: EF caused adverse short-term outcomes such as a higher BPD severity and longer hospital stay. Therefore, extubation in very early preterm infants should be carefully evaluated. Using inotropes, feeding, and RSS at 1 week of age can help predict extubation success., (© 2023. The Author(s).)

The magnetic-flux-dependent dispersions of sub-bands in topologically protected surface states of a topological insulator nanowire manifest as Aharonov-Bohm oscillations (ABOs) observed in conductance measurements, reflecting the Berry's phase of π because of the spin-helical surface states. Here, we used thermoelectric measurements to probe a variation in the density of states at the Fermi level of the surface state of a topological insulator nanowire (Sb-doped Bi 2 Se 3 ) under external magnetic fields and an applied gate voltage. The ABOs observed in the magnetothermovoltage showed 180° out-of-phase oscillations depending on the gate voltage values, which can be used to tune the Fermi wave number and the density of states at the Fermi level. The temperature dependence of the ABO amplitudes showed that the phase coherence was kept to T  = 15 K. We suggest that thermoelectric measurements could be applied for investigating the electronic structure at the Fermi level in various quantum materials., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)

Neurological disorders represent a substantial healthcare burden worldwide due to population aging. Acorus gramineus Solander (AG) and Acorus tatarinowii Schott (AT), whose major component is asarone, have been shown to be effective in neurological disorders. This review summarized current information from preclinical and clinical studies regarding the effects of extracts and active components of AG and AT (e.g., α-asarone and β-asarone) on neurological disorders and biomedical targets, as well as the mechanisms involved. Databases, including PubMed, Embase, and RISS, were searched using the following keywords: asarone, AG, AT, and neurological disorders, including Alzheimer's disease, Parkinson's disease, depression and anxiety, epilepsy, and stroke. Meta-analyses and reviews were excluded. A total of 873 studies were collected. A total of 89 studies were selected after eliminating studies that did not meet the inclusion criteria. Research on neurological disorders widely reported that extracts or active components of AG and AT showed therapeutic efficacy in treating neurological disorders. These components also possessed a wide array of neuroprotective effects, including reduction of pathogenic protein aggregates, antiapoptotic activity, modulation of autophagy, anti-inflammatory and antioxidant activities, regulation of neurotransmitters, activation of neurogenesis, and stimulation of neurotrophic factors. Most of the included studies were preclinical studies that used in vitro and in vivo models, and only a few clinical studies have been performed. Therefore, this review summarizes the current knowledge on AG and AT therapeutic effects as a basis for further clinical studies, and clinical trials are required before these findings can be applied to human neurological disorders., Competing Interests: CONFLICT OF INTEREST The authors have no conflicts of interest to declare., (© 2022 Korean Pharmacopuncture Institute.)

Single-electron sources, formed by a quantum dot (QD), are key elements for realizing electron analogue of quantum optics. We develop a new type of single-electron source with functionalities that are absent in existing sources. This source couples with only one lead. By an AC rf drive, it successively emits holes and electrons cotraveling in the lead, as in the mesoscopic capacitor. Thanks to the considerable charging energy of the QD, however, emitted electrons have energy levels a few tens of millielectronvolts above the Fermi level, so that emitted holes and electrons are split by a potential barrier on demand, resulting in a rectified quantized current. The resulting pump map exhibits quantized triangular islands, in good agreement with our theory. We also demonstrate that the source can be operated with another tunable-barrier single-electron source in a series double QD geometry, showing parallel electron pumping by a common gate driving.

Tunable electrical phase transitions based on the structural and quantum-state phase transitions in two-dimensional transition-metal dichalcogenides have attracted attention in both semiconducting electronics and quantum electronics applications. Here, we report gate-voltage-induced reversible electrical phase transitions in Mo 0.67 W 0.33 Se 2 (MoWSe) field-effect transistors prepared on SiO 2 /Si substrates. In gate-induced depletion regions of the 2H phase, an electrical current resumes flow at 150 K < T < 200 K with decreasing T irrespective of the layer number ( n ) for MoWSe when n < 20. The newly appearing electron-doped-type conducting channel again enters the 2H-phase region when the back-gate voltage increases, accompanied by the negative differential transconductance for four-layer and monolayer devices or by a deflection point in the transfer curves for a multilayer device. The thermal activation energies of the new conducting and 2H-phase branches differ by one order of magnitude at the same gate voltage for both the four-layer and monolayer cases, indicating that the electrical band at the Fermi level was modified. The hysteresis measurements for the gate voltage were performed with a five-layer device, which confirms the reversible electrical transition behavior. The possible origins of the nucleated conducting phase in the depletion region of the 2H phase of MoWSe are discussed.

A processing map is required for Ti alloys to find processing parameters securing a high formability. This study adopted the extreme gradient boosting (XGB) approach of machine learning to predict a flow curve and plot a processing map with less experiments for the first time. The optimum XGB model predicted flow curves of Ti-6Al-2Sn-2Zr-2Mo-2Cr-0.15Si at 1073-1273 K and 10 s -1 . The predicted data were used to plot a processing map, which showed a higher accuracy in the instability map as compared with the map without XGB. The XGB model also anticipated the power dissipation map at low strain rates. The low accuracy at high strain rates would be improved by alleviating the bias towards a flow hardening. This work has successfully proven the potential usefulness of XGB for plotting an enhanced processing map in light of a higher accuracy with less experiments., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Background: The lack of physical activity because of restrictions from the pandemic has increased interest in the deterioration of mental and physical health. This is the first study in Korea to investigate how participation in physical activity is correlated with subjective well-being among Koreans in the early stages of the COVID-19 pandemic., Methods: The survey was conducted among those aged >13 years, from August 24 to September 7, 2020. The process included self-reported surveys, telephone surveys, and face-to-face household interviews; 11,604 people (men=7,758 and women=3,846) participated. Frequency, correlation, and one-way analysis of variance were performed to identify differences between age and sex groups according to the physical activity level, while post-hoc Scheffe tests to examine between-group differences when significant results were observed., Results: Statistically significant correlations were observed between life satisfaction, living environment satisfaction, and levels of happiness and anxiety based on sex and age ( P <0.05). There were significant differences between frequency and time spent on physical activity and subjective well-being according to sex and age ( P <0.05)., Conclusion: The study results are highly generalizable considering the analysis of a large-scale sample within a big area in Korea. The findings emphasize that subjective well-being is influenced by sex, age, frequency, and time spent engaged in physical activity. Such basic data can be helpful for establishing policies related to physical activity., Competing Interests: Conflict of interest The author declares that there is no conflict of interests., (Copyright © 2022 Bae. Published by Tehran University of Medical Sciences.)

Background: Simple and effective risk models incorporating biomarkers associated with left main coronary artery (LMCA) stenosis are limited. This study aimed to validate the novel Bio-Clinical SYNTAX score (Bio-CSS) incorporating N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with LMCA stenosis., Methods: Patients who underwent percutaneous coronary intervention (PCI) for LMCA stenosis using a drug-eluting stent ( n = 275) were included in the study. We developed the Bio-CSS incorporating NT-proBNP and validated the ability of the Bio-CSS to predict major adverse cardiac events (MACEs) and compared its performance to that of the SYNTAX score (SS) and SS II. The MACEs were defined as death, non-fatal myocardial infarction (MI), and repeat revascularizations., Results: The Bio-CSS (34.7 ± 18.3 vs. 51.9 ± 28.4, p < 0.001), as well as SS (23.6 ± 7.3 vs. 26.7 ± 8.1, p = 0.003) and SS II (29.4 ± 9.9 vs. 36.1 ± 12.8, p < 0.001), was significantly higher in patients with MACEs. In the Cox proportional hazards model, the log Bio-CSS (hazard ratio 8.31, 95% CI 1.84-37.55) was an independent prognostic factor for MACEs after adjusting for confounding variables. In the receiver operating characteristic curves, the area under the curve of the Bio-CSS was significantly higher compared to those of SS (0.608 vs. 0.706, p = 0.001) and SS II (0.655 vs. 0.706, p = 0.026). Patients were categorized into the three groups based on the tertiles of the Bio-CSS. Patients in the highest tertile of the Bio-CSS had significantly higher MACEs compared to those in the lower two tertiles (log-rank p < 0.001)., Conclusion: In patients who underwent PCI for LMCA stenosis, the novel Bio-CSS improved the discrimination accuracy of established combined scores, such as SS and SS II. The addition of NT-proBNP to the clinical and angiographic findings in the Bio-CSS could potentially provide useful long-term prognostic information in these patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yoon, Lee, Kim, Kim, Jang, Bae, Yang, Park and Cho.)

Background: The study aimed to analyze happiness levels and leisure life satisfaction related to participation in sports leisure activities, and the differences in satisfaction levels by the type of participation events and participants' demographic backgrounds., Methods: This study was based on the 2020 Korea National Leisure Activities Survey using stratified multistage cluster sampling with a population over the age of 15 years and a nationwide survey. Moreover, a household visit interview survey was conducted from September 7 to November 16, 2020. A total of 10,088 people (5,003 males and 5,085 females) responded to the survey. Frequency analysis, chi-square test, independent t- test, and one-way analysis of variance were performed., Results: The analysis of the distribution of participants and the happiness level and overall leisure life satisfaction between participants in sports and non-sports leisure activities showed significant differences ( P <0.05). Participants in sports leisure activities had higher levels of happiness and satisfaction with leisure activities than those in non-sports leisure activities. There were significant differences in satisfaction with participation in sports leisure activities by type of sports, age, educational level, marital status, and household income level ( P < 0.05)., Conclusion: There were significant differences in participation in sports leisure activities by type of sports, age, educational level, marital status, and household income level, and the satisfaction level of participants in sports leisure activities differed according to these factors. This suggests that various educational efforts are required to combine physical education with sports leisure activities in school., (Copyright © 2022 Bae. Published by Tehran University of Medical Sciences.)

We compare the adiabatic quantized charge pumping performed in two types of InAs nanowire double quantum dots (DQDs), either with tunnel barriers defined by closely spaced narrow bottom gates, or by well-separated side gates. In the device with an array of bottom gates of 100 nm pitch and 10 μm lengths, the pump current is quantized only up to frequencies of a few MHz due to the strong capacitive coupling between the bottom gates. In contrast, in devices with well-separated side gates with reduced mutual gate capacitances, we find well-defined pump currents up to 30 MHz. Our experiments demonstrate that high frequency quantized charge pumping requires careful optimization of the device geometry, including the typically neglected gate feed lines., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Purpose: This study aimed to examine the changes in the characteristics of community-onset fluoroquinolone-resistant (FQ-R) Escherichia coli isolates causing community-acquired acute pyelonephritis (APN) in South Korea., Methods: Blood or urine samples were prospectively collected from patients aged ≥15 years with community-acquired APN who were admitted to one of the eight Korean hospitals included in this study between September 2017 and August 2018. Phylogenetic typing, multilocus sequence typing, and molecular characterization of β-lactamase resistance and plasmid-mediated quinolone resistance (PMQR) determinants were performed. The data were compared with those from a previous study with the same design conducted in 2010-2011., Results: A total of 300 and 346 isolates were identified in 2010-2011 and 2017-2018, respectively. Among them, 76 (22.0%) and 77 (25.7%) FQ-R isolates were identified in 2010-2011 and 2017-2018, respectively. A significantly higher antimicrobial resistance against third-to fourth-generation cephalosporins, including cefotaxime (23.9% vs. 77.9%, P < 0.001), were observed among FQ-R isolates in 2017-2018 than among those in 2010-2011. A higher proportion of ST131 isolates (27.6% vs. 66.2%, P < 0.001), as well as isolates that had extended-spectrum β-lactamase (ESBL)/plasmid-mediated AmpC β-lactamase (PABL) (23.7% vs. 79.2%, P < 0.001), was observed in 2017-2018 than in 2010-2011. Further, more PMQR determinants (11.8% vs. 40.8%, P < 0.001) were observed in 2017-2018 than in 2010-2011., Conclusions: Among uropathogenic FQ-R E. coli isolates in South Korea, the prevalence of ST131 and the proportion of isolates containing ESBL and/or PMQR determinants have increased., Competing Interests: Declaration of competing interest None declared., (Copyright © 2022. Published by Elsevier B.V.)

Background: It has been known that the fear of contagion during the coronavirus disease 2019 (COVID-19) creates time delays with subsequent impact on mortality in patients with acute myocardial infarction (AMI). However, difference of time delay and clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI) or non-STEMI between the COVID-19 pandemic and pre-pandemic era has not been fully investigated yet in Korea. The aim of this study was to investigate the impact of COVID-19 pandemic on time delays and clinical outcome in patients with STEMI or non-STEMI compared to the same period years prior., Methods: A total of 598 patients with STEMI (n = 195) or non-STEMI (n = 403) who underwent coronary angiography during the COVID-19 pandemic (February 1 to April 30, 2020) and pre-pandemic era (February 1 to April 30, 2017, 2018, and 2019) were analyzed in this study. Main outcomes were the incidence of time delay, cardiac arrest, and in-hospital death., Results: There was 13.5% reduction in the number of patients hospitalized with AMI during the pandemic compared to pre-pandemic era. In patients with STEMI, door to balloon time tended to be longer during the pandemic compared to pre-pandemic era (55.7 ± 12.6 minutes vs. 60.8 ± 13.0 minutes, P = 0.08). There were no significant differences in cardiac arrest (15.6% vs. 10.4%, P = 0.397) and in-hospital mortality (15.6% vs. 10.4%, P = 0.397) between pre-pandemic and the pandemic era. In patients with non-STEMI, symptom to door time was significantly longer (310.0 ± 346.2 minutes vs. 511.5 ± 635.7 minutes, P = 0.038) and the incidence of cardiac arrest (0.9% vs. 3.5%, P = 0.017) and in-hospital mortality (0.3% vs. 2.3%, P = 0.045) was significantly greater during the pandemic compared to pre-pandemic era. Among medications, angiotensin converting enzyme inhibitors/angiotensin type 2 receptor blockers (ACE-I/ARBs) were underused in STEMI (64.6% vs. 45.8%, P = 0.021) and non-STEMI (67.8% vs. 57.0%, P = 0.061) during the pandemic., Conclusion: During the COVID-19 pandemic, there has been a considerable reduction in hospital admissions for AMI, time delay, and underuse of ACE-I/ARBs for the management of AMI, and this might be closely associated with the excess death in Korea., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2022 The Korean Academy of Medical Sciences.)

We proposed a metamaterial which exhibits elastic wave localization at extremely low frequencies. First, we opened an extremely low bandgap via elastic foundations. Subsequently, we investigated wave localization by imposing normal defect, which is widely used to capture waves in conventional wave localization systems. However, there were limitations: wave localization was not achieved when a weak bandgap is generated, and the operating frequency of localization is still in the upper part of the bandgap. To overcome wave localization via the normal defect, we proposed a novel metamaterial with a spiral cavity which can tune the resonating frequency depending on the length of the spiral path. By imposing on the spiral cavity inside the elastic foundation-induced metamaterial, we can shift the resonating frequency of the cavity down. Finally, we carried out wave simulations, not only to support the previous eigenfrequency study for the supercell, but also to verify that the finite-size metamaterial can also achieve wave localization at the extremely low frequencies. Through wave simulations, we could observe wave localization even at 77.3 Hz, which is definitely the lower part of the extremely low bandgap., (© 2022. The Author(s).)

Background: Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs. The purpose of this study was to determine the relationship between the appropriateness of antibiotic prescription and outcomes of community-acquired acute pyelonephritis (CA-APN)., Methods: A multicenter prospective cohort study was conducted at eight hospitals in Korea between September 2017 and August 2018. All hospitalized patients aged ≥ 19 years who were diagnosed with CA-APN on admission were recruited. The appropriateness of empirical and definitive antibiotics, as well as the appropriateness of antibiotic treatment duration and route of administration, was evaluated in accordance with the guideline and expert opinions. Clinical outcomes and medical costs were compared between patients who were administered antibiotics 'appropriately' and 'inappropriately.', Results: A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 10 (2.5%) and 18 (5.7%) were administered 'inappropriately' empirical and definitive antibiotics, respectively. Of the 119 patients whose use of both empirical and definitive antibiotics was classified as 'optimal,' 57 (47.9%) received antibiotics over a longer duration than that recommended; 67 (56.3%) did not change to oral antibiotics on day 7 of hospitalization, even after stabilization of the clinical symptoms. Patients who were administered empirical antibiotics 'appropriately' had shorter hospitalization days (8 vs. 10 days, P = 0.001) and lower medical costs (2381.9 vs. 3235.9 USD, P = 0.002) than those who were administered them 'inappropriately.' Similar findings were observed for patients administered both empirical and definitive antibiotics 'appropriately' and those administered either empirical or definitive antibiotics 'inappropriately'., Conclusions: Appropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs., (© 2022. The Author(s).)

Background: nosocomial sepsis remains a significant source of morbidity and mortality in extremely low birth weight (ELBW) infants. Early and accurate diagnosis is very important, but it is difficult due to the similarities in clinical manifestation between the causative microorganisms. We tried to identify the differences between causative microorganisms in clinical and laboratory findings and to help choose antibiotics, when sepsis was suspected in ELBW infants., Methods: a retrospective study was conducted on preterm infants, born at less than 28 weeks of gestation, with a birth weight of less than 1000 g between January 2009 and December 2019. Clinical and laboratory findings of suspected sepsis, after the first 72 h of life, were assessed. We classified them into four groups according to blood culture results (gram positive, gram negative, fungal, and negative culture groups) and compared them., Results: a total of 158 patients were included after using the exclusion criteria, with 45 (29%) in the gram positive group, 35 (22%) in the gram negative group, 27 (17%) in the fungal group, and 51 (32%) in the negative culture group. There were no significant differences in mean gestational age, birth weight, and neonatal morbidities, except for the age of onset, which was earlier in the fungal group than other groups. White blood cell (WBC) counts were the highest in the gram negative group and the lowest in the fungal group. The mean platelet counts were the lowest in the fungal group. C-reactive protein (CRP) levels were the highest in the gram negative group, while glucose was the highest in the fungal group., Conclusions: in conclusion, we showed that there are some differences in laboratory findings, according to causative microorganisms in the nosocomial sepsis of ELBW infants. Increased WBC and CRP were associated with gram negative infection, while decreased platelet and glucose level were associated with fungal infection. These data may be helpful for choosing empirical antibiotics when sepsis is suspected.

Background: It remains uncertain whether intravascular ultrasound (IVUS) use and final kissing balloon (FKB) dilatation would be standard care of percutaneous coronary intervention (PCI) with a simple 1-stent technique in unprotected left main coronary artery (LMCA) stenosis. This study sought to investigate the impact of IVUS use and FKB dilatation on long-term major adverse cardiac events (MACEs) in PCI with a simple 1-stent technique for unprotected LMCA stenosis., Methods: Between June 2006 and December 2012, 255 patients who underwent PCI with 1 drug-eluting stent for LMCA stenosis were analyzed. Mean follow-up duration was 1663 ± 946 days. Long-term MACEs were defined as death, nonfatal myocardial infarction (MI) and repeat revascularizations., Results: During the follow-up, 72 (28.2%) MACEs occurred including 38 (14.9%) deaths, 21 (8.2%) nonfatal MIs and 13 (5.1%) revascularizations. The IVUS examination and FKB dilatation were done in 158 (62.0%) and 119 (46.7%), respectively. IVUS use (20.3 versus 41.2%; log-rank P < 0.001), not FKB dilatation (30.3 versus 26.5%; log-rank P = 0.614), significantly reduced MACEs. In multivariate analysis, IVUS use was a negative predictor of MACEs [hazards ratio 0.51; 95% confidence interval (CI) 0.29-0.88; P = 0.017], whereas FKB dilatation (hazard ratio 1.68; 95% CI, 1.01-2.80; P = 0.047) was a positive predictor of MACEs. In bifurcation LMCA stenosis, IVUS use (18.7 versus 48.0%; log-rank P < 0.001) significantly reduced MACEs. In nonbifurcation LMCA stenosis, FKB dilatation showed a trend of increased MACEs (P = 0.076)., Conclusion: IVUS examination is helpful in reducing clinical events in PCI for LMCA bifurcation lesions, whereas mandatory FKB dilatation after the 1-stent technique might be harmful in nonbifurcation LMCA stenosis., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Abstract: Vitamin D deficiency is common and increases the likelihood of neonatal morbidities in preterm infants. This study assessed vitamin D levels at 1 month of age after 4 weeks of vitamin D supplementation and determined the association between vitamin D levels and neonatal morbidities.This retrospective study included preterm infants with birth weight <1500 g or gestational age <32 weeks born in our hospital between January 2018 and December 2019. They were administered 400 IU of oral vitamin D supplementation after birth according to our policy. The infants were then divided into sufficient (≥20 ng/mL) and deficient (<20 ng/mL) groups according to their serum vitamin D levels at 1 month of age.The vitamin D deficient and sufficient groups included 49 and 41 patients, respectively. The mean gestational age and birth weight. GHT in the vitamin D deficient group were 29.1 ± 2.1 weeks and 1216.1 ± 308.1 g, respectively, and 30.0 ± 1.7 weeks and 1387.6 ± 350.8 g, respectively, in the sufficient group. No significant differences were observed between the 2 groups in demographic and clinical outcomes except for bronchopulmonary dysplasia (BPD), which occurred significantly more often in the vitamin D-deficient group (odds ratio 2.21; 95% confidence interval, 1.85-2.78; P = .02).The results of our study suggest that vitamin D deficiency at 1 month of age is associated with BPD in preterm infants., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

There is insufficient information on the relationship between the N-terminal pro-brain natriuretic peptide (NT-proBNP) level and collateral circulation (CC) formation after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction. We analyzed 857 patients who underwent primary PCI. The serum NT-proBNP levels were measured on the day of admission, and the CC was scored according to Rentrop's classification. Log-transformed NT-proBNP levels were significantly higher in patients with good CC compared to those with poor CC (6.13 ± 2.01 pg/mL versus 5.48 ± 1.97 pg/mL, p < 0.001). The optimum cutoff value of log NT-proBNP for predicting CC was 6.04 pg/mL. Log NT-proBNP ≥ 6.04 pg/mL (odds ratio 2.23; 95% confidence interval 1.51-3.30; p < 0.001) was an independent predictor of good CC. CC development was higher in patients with a pre-TIMI flow of 0 or 1 than those with a pre-TIMI flow of 2 or 3 (22.6% versus 8.8%, p = 0.001). The incidence of left ventricular (LV) dysfunction (< 50%) was greater in patients with a pre-TIMI flow of 0 or 1 (49.8% versus 35.5%, p < 0.001). The release of NT-proBNP was greater in patients with LV dysfunction (34.3% versus 15.6%, p < 0.001). The incidence of good CC was greater in patients with log NT-proBNP levels ≥ 6.04 pg/ml (16.8% versus 26.2%, p = 0.003). The association between NT-proBNP and collateral formation was not influenced by pre-TIMI flow and LV function. NT-proBNP appears to reflect the degree of collateral formation in the early phase of STEMI and might have a new role as a useful surrogate biomarker for collateral formation in patients undergoing primary PCI., (© 2021. The Author(s).)

Myeloid-derived suppressor cells (MDSCs) are heterogeneous populations of immature myeloid cells with immunosuppressive effects that have prognostic potential in patients with malignancies; however, survival analysis studies are sparse. In this study, the prognostic implication of MDSCs was investigated in peripheral blood (PB) and bone marrow (BM) samples from 81 patients with plasma cell myeloma at diagnosis. MDSCs were quantified as monocytic MDSCs (mMDSCs) (CD11b + HLA-DR -/low CD14 + ) and granulocytic MDSCs with neutrophils (gMDSCs-N) (CD11b + HLA-DR -/low CD14 - CD33 + CD15 + ). Serum creatinine and lactate dehydrogenase levels showed a moderate correlation with all MDSC types, except BM-gMDSCs-N; mMDSCs correlated with serum β2-microglobulin level, and PB-mMDSCs showed an inverse correlation with hemoglobin. PB-mMDSC levels were significantly higher in patients with progressive disease than those in patients at diagnosis and complete response. BM-mMDSC levels in patients with progressive disease were also higher than those in patients at diagnosis. Patients with high mMDSCs showed significantly poorer prognosis than patients with low mMDSCs. Multivariate analysis showed high PB-mMDSCs (≥0.3%) as a significant adverse prognostic marker for overall survival. This study demonstrated the independent adverse prognostic impact of PB-mMDSCs in patients with myeloma. PB-mMDSC measurement using whole blood is readily accessible in clinical laboratories, and may be used as a prognostic marker in clinical practice.

The objective of this study was to analyse the genetic relatedness of Clostridioides difficile polymerase chain reaction ribotype 017 (RT017) strains from patients with hospital-acquired C. difficile infection (HA-CDI) in a hospital with a high RT017 prevalence. From 2009 to 2013, 200 RT017 strains (26.8%) were collected from 745 HA-CDI patient isolates. They comprised 64 MLVA types, and 197 (98.5%) strains were genetically related to 5 clonal complexes (CCs). The largest cluster, CC-A, included 163 isolates of 40 MLVA types. CC-A accounted for 20% of RT017 strains in 2009 and sharply increased to 94.9% in 2010, 94% in 2011, 86.2% in 2012, and 73.5% in 2013. The other 4 CCs included 20 isolates with 7 MLVA types. The resistance rates of antimicrobials were as follows: clindamycin 100%, moxifloxacin 99%, rifaximin 88.5%, and vancomycin 1%. All isolates were susceptible to metronidazole and piperacillin/tazobactam. Comparing antibiotic resistance among CCs, the geometric mean of the minimum inhibitory concentrations of moxifloxacin, vancomycin, and piperacillin/tazobactam were significantly higher for CC-A isolates than for the other CCs. RT017 clones constantly evolved over the 5 years studied with regard to genetic relatedness. The levels of antibiotic resistance may contribute to the persistence of organisms in the institution.