Synthesis of Highly Dispersible Functionalized Carbon Nanotubes as Conductive Material through a Facile Drying Process for High-Power Lithium-ion Batteries.

Herein, surface-functionalized carbon nanotubes (CNTs) were successfully synthesized by dry ball milling that facilitates industrial application. The optimal conditions were determined by analyzing the physicochemical characteristics of CNTs, including the content of the carboxyl group (-COOH) induced on the surface of CNTs by co-existing dry ice based on the ball milling time. Among them, 30 s ball milling (CNTs-30s) showed a high dispersibility in N-methyl-2-pyrrolidone (NMP) while retaining most carboxyl groups and maintaining the intrinsic high conductivity. In the evaluation of rate capability and 5 C/5 C cyclability applied to the Li1+x (Ni1-y-z Coy Mnz )1-x O2 with 60 % Ni (NCM622) cathode, CNTs-30s showed excellent performance based on a well-formed conductive network. Regarding improved dispersion properties and electrochemical performance, the optimal surface functionalization conditions, dispersibility, and electrode properties according to the processing time were analyzed; based on these, the correlation with electrochemical performance was confirmed.

Body CT and PET/CT detection of extracranial lymphoma in patients with newly diagnosed central nervous system lymphoma.

BACKGROUND: We aimed to investigate the detection rate of body CT or PET/CT for sites of extracranial disease in patients with a new pathological diagnosis of CNS DLBCL and to identify factors associated with sites of extracranial disease. METHODS: An international multicenter cohort study of consecutive immunocompetent patients with a new diagnosis of CNS DLBCL confirmed by brain biopsy who underwent CT and/or PET/CT to evaluate for sites of extracranial disease between 1998 and 2019. The primary outcome was the detection rate of extracranial lymphoma by CT or PET/CT. Subgroup analyses according to age and EBV status were also performed. Logistic regression analyses were performed to determine factors related to sites of extracranial disease. Detection rates of CT and PET/CT were compared. RESULTS: One thousand and forty-three patients were included. The overall detection rate of CT or PET/CT was 2.6% (27/1043). The treatment approach was adjusted in 74% of these patients. Multivariable analysis demonstrated that age >61 years (OR, 3.10; P = .016) and EBV positivity (OR, 3.78; P = .045) were associated with greater odds of extracranial lymphoma. There was no statistically significant difference in detection rate between CT and PET/CT (P = .802). In patients ≤61 years old, the false-referral rates were significantly higher than the detection rates (P < .001). CONCLUSION: Our results showed increased odds of extracranial lymphoma in patients with older age or EBV-positive lymphoma. Treatment was adjusted in a majority of patients diagnosed with extracranial lymphoma, thereby supporting the current guidelines for the use of contrast-enhanced body CT or PET/CT in patients with newly diagnosed CNS DLBCL.

Efficacy and Safety of Surgical Resection in Elderly Patients with Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis1

Background/Aims@#With increased life expectancy, the management of elderly hepatocellular carcinoma (HCC) patients became a crucial issue, yet it is still challenging due to comorbidities and high surgical risks. While surgical resection is considered as primary treatment for eligible HCC patients, systematic evidence on its outcomes in elderly patients remains scarce. In this review, we aimed to analyze the efficacy and safety outcomes of surgical resection in elderly HCC patients. @*Methods@#The studies included in this meta-analysis were selected from Ovid-MEDLINE, OvidEmbase, CENTRAL, KoreaMed, KMbase, and KISS databases following a predefined protocol.Efficacy outcomes included overall survival and disease-free survival, while the safety outcomes included postoperative mortality and complications. @*Results@#Patients in the elderly group (≥65 years) who underwent surgery exhibited non-inferior overall survival (hazard ratio [HR], 1.26; 95% confidence interval [CI], 0.92 to 1.74) and diseasefree survival (HR, 1.03; 95% CI, 0.99 to 1.08) compared to the non-elderly group. Overall postop-erative mortality exhibited no statistical difference (odds ratio [OR], 1.07; 95% CI, 0.87 to 1.31), but 30-day, 90-day, and in-hospital mortality were higher in the elderly group. The incidence of overall complications was higher in the elderly group (OR, 1.44; 95% CI, 1.22 to 1.69). Sensitivity analysis for the super elderly group (≥80 years) showed significantly higher in-hospital mortality compared to the non-super elderly group (OR, 2.51; 95% CI, 1.16 to 5.45). @*Conclusions@#The efficacy outcome of surgical resection in the elderly HCC patients was not worse than that in the non-elderly HCC patients, while in-hospital mortality and complications rates were higher. Therefore, surgical resection should be purposefully considered in the elderly population, with careful candidate selection.

Additional nodules detected using EOB-MRI in patients with resectable single hepatocellular carcinoma: an implication for active treatment strategy

Background@#/Aim: Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOBMRI) further enhances the identification of additional hepatic nodules compared with computed tomography (CT) alone; however, the optimal treatment for such additional nodules remains unclear. We investigated the long-term oncological effect of aggressive treatment strategies for additional lesions identified using EOB-MRI in patients with hepatocellular carcinoma (HCC). @*Methods@#Data from 522 patients diagnosed with solitary HCC using CT between January 2008 and December 2012 were retrospectively reviewed. Propensity score-matched (PSM) analysis was used to compare the oncologic outcomes between patients with solitary HCC and those with additional nodules on EOB-MRI after aggressive treatment (resection or radiofrequency ablation [RFA]). @*Results@#Among the 383 patients included, 59 had additional nodules identified using EOB-MRI. Compared with patients with solitary HCC, those with additional nodules on EOB-MRI had elevated total bilirubin, aspartate transaminase, and alanine transaminase; had a lower platelet count, higher MELD score, and highly associated with liver cirrhosis (P<0.05). Regarding long-term outcomes, 59 patients with solitary HCC and those with additional nodules after PSM were compared. Disease-free survival (DFS) and overall survival (OS) were comparable between the two groups (DFS, 60.4 vs. 44.3 months, P=0.071; OS, 82.8 vs. 84.8 months, P=0.986). @*Conclusion@#The aggressive treatment approach, either resection or RFA, for patients with additional nodules identified on EOBMRI was associated with long-term survival comparable with that for solitary HCC. However, further studies are required to confirm these findings.

Transradial Versus Transfemoral Access for Bifurcation Percutaneous Coronary Intervention Using SecondGeneration Drug-Eluting Stent

Background@#The benefits of transradial access (TRA) over transfemoral access (TFA) for bifurcation percutaneous coronary intervention (PCI) are uncertain because of the limited availability of device selection. This study aimed to compare the procedural differences and the in-hospital and long-term outcomes of TRA and TFA for bifurcation PCI using secondgeneration drug-eluting stents (DESs). @*Methods@#Based on data from the Coronary Bifurcation Stenting Registry III, a retrospective registry of 2,648 patients undergoing bifurcation PCI with second-generation DES from 21 centers in South Korea, patients were categorized into the TRA group (n = 1,507) or the TFA group (n = 1,141). After propensity score matching (PSM), procedural differences, in-hospital outcomes, and device-oriented composite outcomes (DOCOs; a composite of cardiac death, target vessel-related myocardial infarction, and target lesion revascularization) were compared between the two groups (772 matched patients each group). @*Results@#Despite well-balanced baseline clinical and lesion characteristics after PSM, the use of the two-stent strategy (14.2% vs. 23.7%, P = 0.001) and the incidence of in-hospital adverse outcomes, primarily driven by access site complications (2.2% vs. 4.4%, P = 0.015), were significantly lower in the TRA group than in the TFA group. At the 5-year follow-up, the incidence of DOCOs was similar between the groups (6.3% vs. 7.1%, P = 0.639). @*Conclusion@#The findings suggested that TRA may be safer than TFA for bifurcation PCI using second-generation DESs. Despite differences in treatment strategy, TRA was associated with similar long-term clinical outcomes as those of TFA. Therefore, TRA might be the preferred access for bifurcation PCI using second-generation DES.

Glymphatic Magnetic Resonance Imaging: Part I—Methodologies for Evaluation of the Glymphatic System

Glymphatic magnetic resonance imaging (MRI) is an advanced technique for visualizing the glymphatic system of the brain. We reviewed recent research findings that utilized glymphatic MRI techniques to elucidate the intricate physiological processes of the glymphatic system. We introduce the significance of assessing the glymphatic system by exploring various MRI methodologies, each possessing unique advantages and limitations.Some of these methodologies involve the use of gadolinium-based contrast agents to map the distribution within the brain, while others do not require the use of contrast agents. These approaches offer distinct insights and constraints, enabling researchers to investigate the glymphatic system using MRI. Eventually, glymphatic MRI methodologies will provide invaluable insights to enhance our understanding of the complex pathophysiology of the brain. These findings are expected to contribute significantly to our knowledge and treatment of brain disorders, particularly neurodegenerative diseases. Glymphatic MRI is a crucial reference for exploring promising research avenues in which MRI techniques can play a pivotal role in comprehending and visualizing the brain’s glymphatic system.

Glymphatic Magnetic Resonance Imaging: Part II—Applications in Sleep and Neurodegenerative Diseases

The glymphatic system plays a crucial role in brain waste clearance, with glymphatic magnetic resonance imaging (MRI) techniques highlighting its significance in understanding neurodegenerative diseases. This review emphasizes the intricate relationship between sleep, the glymphatic system, and the onset of conditions such as Alzheimer's disease (AD), idiopathic normal pressure hydrocephalus (iNPH), Parkinson's disease (PD), and other neurological diseases. Key findings revealed that sleep disruptions can impair the glymphatic system and potentially accelerate the progression of neurodegenerative diseases. In AD, amyloid β plaque accumulation correlates with glymphatic dysfunction, while in iNPH, impaired glymphatic functionality may result in waste accumulation, such as amyloid-beta accumulation in AD. Research on PD has underscored the potential role of the glymphatic system in α-synuclein clearance. In conclusion, as we delve into the glymphatic system using MRI techniques, we anticipate a richer understanding of neurodegenerative diseases, offering prospects for innovative therapeutic interventions.

Giant Coronary Artery Aneurysm with Thrombosis Complicated in a Patient with Idiopathic Hypereosinophilic Syndrome

Idiopathic hypereosinophilic syndrome (iHES) is a rare systemic disease that is characterized by persistent peripheral eosinophilia (absolute eosinophil count ≥1500/uL) for more than 6 months, with end-organ damage and absence of a primary cause for eosinophilia. Coronary artery aneurysm (CAA) is a rare but life-threatening complication. Here, we report a case of CAA with thrombosis in a patient with iHES in whom the disease activity was well-controlled (eosinophil count <500/uL) for several years. Despite modest control of the disease activity, giant CAA can be associated with iHES; and therefore, close surveillance and monitoring for the development of complications is warranted.

Assessment of Esophageal Reconstruction via Bioreactor Cultivation of a Synthetic Scaffold in a Canine Model

Objectives@#. Using tissue-engineered materials for esophageal reconstruction is a technically challenging task in animals that requires bioreactor training to enhance cellular reactivity. There have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in initial epithelialization in the special environment of peristalsis. The purpose of this study was to evaluate the potential of an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a double-layered polymeric scaffold and a custom-designed mesenchymal stem cell-based bioreactor system in a canine model. @*Methods@#. We fabricated a novel double-layered scaffold as a tissue-engineered esophagus using an electrospinning technique. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. After 3 days of cultivation using the bioreactor system, tissue-engineered artificial esophagus was transplanted into a partial esophageal defect (5×3 cm-long resection) in a canine model. @*Results@#. Scanning electron microscopy (SEM) showed that the electrospun fibers in a tubular scaffold were randomly and circumferentially located toward the inner and outer surfaces. Complete recovery of the esophageal mucosa was confirmed by endoscopic analysis and SEM. Esophagogastroduodenoscopy and computed tomography also showed that there were no signs of leakage or stricture and that there was a normal lumen with complete epithelialization. Significant regeneration of the mucosal layer was observed by keratin-5 immunostaining. Alpha-smooth muscle actin immunostaining showed significantly greater esophageal muscle regeneration at 12 months than at 6 months. @*Conclusion@#. Custom-designed bioreactor cultured electrospun polyurethane scaffolds can be a promising approach for esophageal tissue engineering.

Intraindividual Comparison of MRIs with Extracellular and Hepatobiliary Contrast Agents for the Noninvasive Diagnosis of Hepatocellular Carcinoma Using the Korean Liver Cancer Association–National Cancer Center 2022 Criteria / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The aim of the present study was to evaluate the per-lesion sensitivity and specificity of the Korean Liver Cancer Association–National Cancer Center (KLCA-NCC) 2022 criteria for the noninvasive diagnosis of hepatocellular carcinoma (HCC), with intraindividual comparison of the diagnostic performance of magnetic resonance imaging with extracellular agents (ECA-MRI) and hepatobiliary agents (HBA-MRI). @*Materials and Methods@#Patients at high risk for HCC who were referred to a tertiary academic institution for hepatic lesions with size ≥ 10 mm between July 2019 and June 2022 were enrolled. A total of 91 patients (mean age, 58.1 years; 76 men and 15 women) with 118 lesions who underwent both ECA-MRI and HBA-MRI were eligible for final analysis. The per-lesion sensitivities and specificities of the KLCA-NCC 2022 criteria using ECA-MRI and HBA-MRI were compared using McNemar’s test. @*Results@#The 118 lesions were 93 HCCs, 4 non-HCC malignancies, and 21 benign lesions. On HBA-MRI, the “definite” HCC category showed significantly higher sensitivity than ECA-MRI (78.5% vs. 58.1%, p 0.999). For “probable” or “definite” HCC categories, there were no differences in the sensitivity (84.9% vs. 84.9%, p > 0.999) and specificity (84.0% vs. 84.0%, p > 0.999) between ECA-MRI and HBA-MRI. @*Conclusion@#The “definite” HCC category of the KLCA-NCC 2022 criteria showed higher sensitivity in diagnosing HCC on HBA-MRI compared with ECA-MRI, without compromising specificity. There were no significant differences in the sensitivity and specificity of “probable” or “definite” HCC categories according to ECA-MRI and HBA-MRI.

Clinical Characteristics and Outcomes of Children With SARS-CoV-2 Infection During the Delta and Omicron VariantDominant Periods in Korea

Background@#Data on the clinical characteristics of pediatric patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant infection are limited. We aimed to evaluate the clinical features and outcomes of children with SARS-CoV-2 infection before and after omicron variant dominance in Korea. @*Methods@#A multicenter retrospective cohort study was conducted in hospitalized patients aged ≤ 18 years with laboratory-confirmed SARS-CoV-2 infection at five university hospitals in South Korea. The study periods were divided into the delta (from August 23, 2021 to January 2, 2022) and omicron (from January 30 to March 31, 2022). @*Results@#In total, 612 hospitalized patients were identified (211, delta; 401, omicron). During the omicron and delta periods, the proportions of individuals with serious illness (moderate, severe, and critical severity) were 21.2% and 11.8%, respectively (P = 0.034). Compared with the delta period, the proportions of patients with moderate illness increased significantly in the age groups of 0–4 years (14.2% vs. 3.4%) and 5–11 years (18.6% vs. 4.2%) during the omicron period. During the two periods, the proportions of patients with complex chronic diseases (delta, 16.0% vs. 4.3%, P = 0.040; omicron, 27.1% vs. 12.7%; P= 0.002), respiratory diseases except for asthma (delta, 8.0% vs. 0.0%, P = 0.013; omicron, 9.4% vs. 1.6%; P = 0.001), and neurologic diseases (delta, 28.0% vs. 3.2%, P < 0.001; omicron, 40.0% vs. 5.1%, P < 0.001) were significantly higher in patients with serious illness than in those with nonserious illness. During the delta period, the risk for serious illness was higher among patients with obesity (adjusted odds ratio [aOR], 8.18; 95% confidence interval [CI], 2.80–27.36) and neurologic diseases (aOR, 39.43; 95% CI, 6.90–268.3) and aged 12–18 years (aOR, 3.92; 95% CI, 1.46–10.85). However, the presence of neurologic disease (aOR, 9.80; 95% CI, 4.50–22.57) was the only risk factor for serious illness during the omicron period. During the omicron period, the proportions of patients with croup (11.0% vs. 0.5%) and seizures (13.2% vs. 2.8%) increased significantly compared with the delta period. @*Conclusion@#Compared with the delta period, the proportions of young children and patients with complex comorbidities were higher during the omicron period in Korea. Patients

Etiology and Risk Factors of Community-Acquired Pneumonia in Hospitalized Children During the COVID-19 Pandemic in South Korea

Purpose@#This study aimed to identify the etiology and risk factors of community-acquired pneumonia (CAP) requiring hospitalization in Korean children during the coronavirus disease 2019 (COVID-19) pandemic. @*Methods@#Clinical information of children admitted with CAP to Seoul National University Children’s Hospital (SNUCH) between January 1, 2021, and February 28, 2022, was retrospectively collected and analyzed. In addition, the etiologic diagnosis and demographic data of children with CAP who were discharged at the other seven hospitals between January and February 2022 were collected. Pneumonia was diagnosed using strict criteria comprising clinical symptoms, physical examination findings, and chest radiographic findings. @*Results@#Among 91 children hospitalized with CAP at SNUCH during the 14-month period, 68.4% were aged <5 years and 79.1% had underlying diseases. Among the 95 CAP cases, respiratory assistance was required in 70.5%, and the use of a ventilator was required in 20.0%.A total of five patients expired, all of whom were either immunocompromised or had underlying neurological diseases. Neurological diseases and immunosuppression were significantly correlated with respiratory assistance (P=0.003) and death (P=0.014). A total of 55% of the detected respiratory pathogens were viruses, the most common of which was rhinovirus at 35.9%. Among the 169 children hospitalized for CAP at the eight institutions, ≥1 respiratory virus was detected in 92.3%, among which respiratory syncytial virus (79.8%) was the most prevalent. @*Conclusions@#Even during the COVID-19 pandemic, Korean children were hospitalized with CAP caused by seasonal respiratory viral pathogens. Although atypical and pyogenic bacteria were not detected, continuous clinical monitoring and further prospective studies should be conducted.

Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996–2020

Background@#The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI). @*Methods@#A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed. @*Results@#A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (rs = −0.430, P = 0.036), H. influenzae (rs = −0.922, P 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

Safety and Efficacy of Everolimus-Eluting Bioresorbable Vascular Scaffold Versus Second-Generation Drug-Eluting Stents in Real-World Practice

Background@#The risk of device thrombosis and device-oriented clinical outcomes with bioresorbable vascular scaffold (BVS) was reported to be significantly higher than with contemporary drug-eluting stents (DESs). However, optimal device implantation may improve clinical outcomes in patients receiving BVS. The current study evaluated mid-term safety and efficacy of Absorb BVS with meticulous device optimization under intravascular imaging guidance. @*Methods@#The SMART-REWARD and PERSPECTIVE-PCI registries in Korea prospectively enrolled 390 patients with BVS and 675 patients with DES, respectively. The primary endpoint was target vessel failure (TVF) at 2 years and the secondary major endpoint was patientoriented composite outcome (POCO) at 2 years. @*Results@#Patient-level pooled analysis evaluated 1,003 patients (377 patients with BVS and 626 patients with DES). Mean scaffold diameter per lesion was 3.24 ± 0.30 mm in BVS group.Most BVSs were implanted with pre-dilatation (90.9%), intravascular imaging guidance (74.9%), and post-dilatation (73.1%) at proximal to mid segment (81.9%) in target vessel.Patients treated with BVS showed comparable risks of 2-year TVF (2.9% vs. 3.7%, adjusted hazard ratio [HR], 1.283, 95% confidence interval [CI], 0.487–3.378, P = 0.615) and 2-year POCO (4.5% vs. 5.9%, adjusted HR, 1.413, 95% CI, 0.663–3.012,P = 0.370) than those with DES. The rate of 2-year definite or probable device thrombosis (0.3% vs. 0.5%, P = 0.424) was also similar. The sensitivity analyses consistently showed comparable risk of TVF and POCO between the 2 groups. @*Conclusion@#With meticulous device optimization under imaging guidance and avoidance of implantation in small vessels, BVS showed comparable risks of 2-year TVF and device thrombosis with DES.

Impact of Atrial Fibrillation on Patients Undergoing Transcatheter Aortic Valve Implantation (TAVI): The K-TAVI Registry

Purpose@#The incidence and prognostic implications of atrial fibrillation (AF) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI) are controversial, especially for Korean patients. Furthermore, the pattern of antithrombotic therapy for these patients is unknown. The present study sought to identify the impact of AF on Korean patients undergoing TAVI and demonstrate the status of antithrombotic therapy for these patients. @*Materials and Methods@#A total of 660 patients who underwent TAVI for severe AS were recruited from the nationwide K-TAVI registry in Korea. The enrolled patients were stratified into sinus rhythm (SR) and AF groups. The primary endpoint was all-cause death at 1-year. @*Results@#AF was recorded in 135 patients [pre-existing AF 108 (16.4%) and new-onset AF 27 (4.1%)]. The rate of all-cause death at 1 year was significantly higher in patients with AF than in those with SR [16.2% vs. 6.4%, adjusted hazard ratio (HR): 2.207, 95% confidence interval (CI): 1.182–4.120, p=0.013], regardless of the onset timing of AF. The rate of new pacemaker insertion at 1 year was also significantly higher in patients with AF than in those with SR (14.0% vs. 5.5%, adjusted HR: 3.137, 95%CI: 1.621–6.071, p=0.001).Among AF patients, substantial number of patients received the combination of multiple antithrombotic agents (77.8%), and the most common combination was that of aspirin and clopidogrel (38.1%). @*Conclusion@#AF was an independent predictor of 1-year mortality and new pacemaker insertion in Korean patients undergoing TAVI.

Risk Factors for Severe COVID-19 in Children: A Systematic Review and Meta-Analysis

Background@#Coronavirus disease 2019 (COVID-19) has been the most important global issue since December 2019. Although the clinical course of COVID-19 is known to be milder in children than in adults, associated hospitalizations among children have increased since the emergence of contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and the achievement of a high vaccination rate in adults. Considering these global and domestic situations, we believe that risk stratification in children with COVID-19 is urgently needed for decision making regarding hospitalization priority in children infected with SARS-CoV-2 and vaccination priority against COVID-19. @*Methods@#This systematic review and meta-analysis was performed by comprehensively searching the PubMed, EMBASE, Scopus and KoreaMed databases through August 25, 2021.The criteria for enrollment were “severe COVID-19” as poor outcomes (intensive care unit admission, invasive mechanical ventilation, and/or death) and underlying comorbidities before SARS-CoV-2 infection. @*Results@#Among 872 screened studies, 17 articles were included in the systematic review, and 10 articles were included in the meta-analysis. Neonate (risk ratio [RR], 2.69; 95% confidence interval [CI], 1.83–3.97), prematurity in young infants (RR, 2.00; 95% CI, 1.63–2.46), obesity (RR, 1.43; 95% CI, 1.24–1.64), diabetes (RR, 2.26; 95% CI, 1.95–2.62), chronic lung disease (RR, 2.62; 95% CI, 1.71–4.00), heart disease (RR, 1.82; 95% CI, 1.58–2.09), neurologic disease (RR, 1.18; 95% CI, 1.05–1.33), and immunocompromised status (RR, 1.44; 95% CI, 1.01–2.04) were significant risk factors for severe COVID-19 in children. In the subgroup analysis, age younger than 3 months (RR, 0.26; 95% CI, 0.11–0.66), asthma (RR, 1.08; 95% CI, 0.98–1.20), and neurodevelopmental disorders (RR, 0.88; 95% CI, 0.75–1.04) were not risk factors for severe COVID-19. @*Conclusion@#Children with comorbidities such as obesity, diabetes, heart disease, chronic lung diseases other than asthma, seizure disorders, and an immunocompromised status had a high prevalence of severe COVID-19. Neonate and premature infants had a high risk of severe COVID-19. Defining the high-risk group for severe COVID-19 could help to guide hospital admission and priority for vaccination against SARS-CoV-2.

Delphi Survey for COVID-19 Vaccination in Korean Children Between 5 and 11 Years Old

Purpose@#During the coronavirus disease 2019 (COVID-19) pandemic, we conducted a Delphi survey that included the experts from the field of COVID-19 immunization in children aged 5–11 years. The aim was to organize collective expert opinions on COVID-19 vaccination in young children in the Republic of Korea, and so thus assist the vaccination policy. @*Methods@#The panels included pediatric infectious disease specialists, preventive medicine experts, infectious disease physicians, and COVID-19 vaccine experts consulting the Ministry of Health and Welfare. The Delphi survey was conducted online using a questionnaire from February 14 to February 27, 2022. @*Results@#The Delphi panels agreed that children were vulnerable to COVID-19, and the severity of illness was modest. Furthermore the panels reported that children with chronic illness were more susceptible to a worsening clinical course. There were generally positive opinions on the effectiveness of COVID-19 vaccination in children aged 5–11 years, and experts gathered a slightly positive opinion that the adverse events of pediatric COVID-19 were not numerous. The benefits of COVID-19 vaccination were evaluated at a level similar to the potential risks in children.Currently, the only approved mRNA platform vaccine in children seemed to be sustainable; however, the recombinant protein platform COVID-19 vaccines were evaluated as better options. @*Conclusions@#Due to the surge of the Omicron variant and an increase in pediatric cases, the COVID-19 vaccination in young children may have to be considered. Panels had neutral opinions regarding the COVID-19 vaccination in children aged 5–11 years. Thus monitoring of the epidemiology and the data about the safety of COVID-19 vaccination should be continued.

Therapeutics in the Treatment of COVID-19 for Children and Adolescents

Coronavirus disease 2019 (COVID-19) presents as a mild-to-moderate respiratory illness in most children. However, a small proportion of children with COVID-19 develop severe or critical illnesses. Although pediatric clinical trials for the treatment of COVID-19 are sparse, some drugs are available for children and adolescents with severe COVID-19. This review summarizes clinical data focusing on antiviral agents and immunomodulators for use in treating COVID-19. In addition, current recommendations for therapeutics for children and adolescents with COVID-19 are discussed.

Local Drug Delivery Strategies for Glioblastoma Treatment

Glioblastoma multiforme (GBM) is a brain tumor notorious for its malignancy. The key reason for the limited efficacy of standard treatment is the high recurrence rate of GBM, even after surgical resection. Hence, intensive postsurgical chemical therapies, such as the systemic delivery of various drugs and/ or drug combinations, are typically followed after surgery. However, overcoming the blood-brain barrier by systemic administration to efficiently deliver drugs to the brain tumor remains a daunting goal. Therefore, various local drug delivery methods showing potential for improved therapeutic efficacy have been proposed. In particular, the recent application of electronic devices for the controlled delivery of chemotherapy drugs to GBM tissue has attracted attention. We herein review the recent progress of local drug delivery strategies, including electronics-assisted strategies, at the research and commercial level. We also present a brief discussion of the unsolved challenges and future research direction of localized chemotherapy methods for GBM.

Clavicular Tunnel Complications after Coracoclavicular Reconstruction in Acute Acromioclavicular Dislocation: Coracoid Loop versus Coracoid Tunnel Fixation

Background@#The purpose of this study was to compare clavicular tunnel complications after coracoclavicular (CC) reconstruction between a coracoid loop fixation group and a coracoid tunnel fixation group. We hypothesized that clavicular tunnel complications would be more common in the coracoid loop group. @*Methods@#This retrospective study evaluated 24 patients who underwent CC reconstruction using coracoid tunnel fixation (n = 14) and coracoid loop fixation (n = 10). Radiographic measurements included the CC distance and clavicular tunnel diameter. Clavicular tunnel complications such as tunnel widening and clavicular tunnel fractures were investigated. Clinical outcomes were assessed using the American Shoulder and Elbow Surgeons Shoulder score and the University of California at Los Angeles Shoulder score. @*Results@#The mean follow-up period was 17.5 months (range, 11–38 months). The final clavicular tunnel diameter and the increase in the clavicular tunnel diameter in millimeter and percentage were significantly greater in the coracoid loop group than in the coracoid tunnel group (all p < 0.05). Clavicular tunnel widening more than 100% was found in 5 patients, all belonging to the coracoid loop group. Clavicular tunnel fractures occurred in 3 patients (all in the coracoid loop group). Fracture was associated with severe tunnel widening (more than 100% increase). The mean value of the final clavicular tunnel diameter in patients with fractures was significantly larger than that in patients without (12.7 ± 3.3 mm vs. 8.4 ± 1.5 mm, p = 0.016). @*Conclusions@#Clavicular tunnel complications such as significant tunnel widening and fractures after CC reconstructions in acromioclavicular dislocations were common with the coracoid loop fixation technique. A greater clavicular tunnel widening and resultantly enlarged tunnel diameter might increase the risk of fracture through the clavicular tunnel.