Background: Activin A is involved in the inflammatory response, wound repair, and skin fibrosis. Serum activin A concentrations change during the menstrual cycle, and this can lead to periodic exacerbation of atopic dermatitis. Objective: To determine the effect of activin A on the cytokine expression profiles of human fibroblasts and keratinocytes under atopic dermatitis-like conditions. Methods: Cultured human fibroblasts and keratinocytes were treated with activin A in combination with interleukin (IL)-4 and IL-13 to determine the changes in cytokine concentrations. Results: Activin A decreased the expression of IL-1β and IL-23 mRNA in fibroblasts. IL-4 and IL-13 increased the expression of IL-6 and IL-16 and decreased the expression of IL-1α, IL-1β, IL-8, IL-10, and IL-23 in fibroblasts. In keratinocytes, IL-4 and IL-13 increased the expression of IL-1α and IL-1β and decreased the expression of IL-8. Activin A treatment in combination with IL-4 and IL-13 significantly increased the expression of IL-1α, IL-6, IL-8, IL-10, IL-16, and IL-23 and decreased the expression of IL-1β in fibroblasts. In keratinocytes, only IL-8 expression was significantly increased following treatment with activin A, IL-4, and IL-13. Conclusion Activin A modulates cytokine expression in a cell type dependent manner under conditions mimicking atopic dermatitis, suggesting its potential involvement in cutaneous inflammatory regulation.

Background: Non-thermal atmospheric pressure plasma (NTAP) generates reactive oxygen species, reactive nitrogen species, and ultraviolet radiation, which can inactivate microorganisms.Onychomycosis treatment is challenging, and its prognosis is poor owing to mixed infections and dermatophytosis. Although NTAP has shown in vitro antifungal effects against dermatophytes and yeast, its efficacy against non-dermatophyte molds (NDMs) and in clinical or nail model studies remains poorly understood. Objective: We evaluated the effects of NTAP on fungi, including NDMs, and infected nail plates. Methods: For the in vitro experiments, Trichophyton rubrum, Candida albicans, Aspergillus fumigatus, and Fusarium oxysporum strains were exposed to NTAP. After NTAP exposure (2,4 and 6 minutes), growth curve, cell viability, and biofilm biomass were assessed by absorbance wavelength of 600 nm, XTT assay, and crystal violet staining, respectively. For the ex vivo experiments, infected nail plates were analyzed using a scanning electron microscope. Results: T. rubrum and C. albicans showed greater growth inhibition with increasing NTAP exposure time, whereas A. fumigatus showed enhanced growth after 6 minutes exposure. Many fungal elements within the subungual hyperkeratosis of the ex vivo specimen were all damaged following NTAP exposure. Conclusion NTAP has antifungal effects on dermatophytes, yeast, and NDMs. We suggest that the intensity and time of NTAP application should be adjusted according to each strain and can be more effective when NTAP directly reaches the hyphae on the nail bed or subungual hyperkeratosis.

Background: As nationwide government-led whole-genome sequencing (WGS) projects progress, optimizing the clinical integration of large-scale WGS results is crucial. We explored how the initial analysis from Korea’s First WGS Pilot Study for Rare Diseases was applied in clinical practice, and then we reanalyzed the data comprehensively at Samsung Medical Center (SMC) Seoul, Korea. Methods: A prospective cohort study designed to collect WGS data under a Korean national initiative was conducted from August 2020 to December 2021. We focused on patients with rare diseases recruited from 16 university hospitals. The participants included 5,000 individuals (2,200 probands and 2,800 family members). The initial WGS data and diagnostic reference reports (from 682 probands and 484 family members), generated based on the First Korean WGS Pilot Study for Rare Diseases, were subsequently reanalyzed by SMC. Results: The initial analysis of the First Korean WGS Pilot Study data revealed a diagnostic rate of 17%. Upon receiving these results, the SMC conducted two rounds of reanalysis, increasing the diagnostic rate from 15% in the first analysis, to 18% in the second, and finally to 24% in the third (P = 1.6 × 10 −5 ). Key factors in improving the genetic diagnosis included increased detection of novel (likely) pathogenic variants (P = 1.0 × 10 −4 ), improved diagnostic rates with larger family recruitment (P = 0.004), and refined clinical information for more precise genotype–phenotype correlation analysis (40%). Conclusions Although national WGS projects lay a foundation for rare disease diagnosis, hospital-level reanalysis and multidisciplinary collaborations are crucial for optimizing diagnostic outcomes.

Flow cytometric lymphocyte subset analysis (FCLSA) is essential for assessing immune status across various diseases and clinical settings. We surveyed current clinical laboratory practices related to FCLSA to establish a baseline reference for future standardization in Korea. Nine university hospitals actively performing FCLSA responded to the 22-question survey, which covered seven categories of laboratory practice. These hospitals used commercial reagent antibody kits from either Beckton Dickinson Biosciences (N = 4) or Beckman Coulter Diagnostics (N = 5). Most hospitals performed daily instrument setup and scheduled maintenance every 2–6 months. Two levels of commercial quality control materials were routinely used each day. Sample and reagent antibody volumes varied across hospitals, even when the same reagent kit was used. Acquired cell counts ranged from 5 × 10 3 to 5 × 10 4 cells, with two hospitals adjusting counts based on the cell type analyzed. Most laboratories reported percentages and general opinions; some additionally reported white blood cell and lymphocyte counts, along with lymphocyte percentages. This is the first comprehensive survey on the clinical laboratory practice of FCLSA in Korea.Standardization of FCLSA should be accelerated to ensure reliable and reproducible results.

The Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) is widely used for risk stratification in pheochromocytoma and paraganglioma (PPGL), but its clinical utility is limited by inter-observer variability of its parameters and inconsistent predictive performance. Methods: We conducted a multicenter retrospective study of 1,518 patients with PPGL from five tertiary referral centers in Korea. Prognostic utility of PASS system was assessed using logistic regression, Kaplan-Meier analysis, and receiver operating characteristic (ROC) curve analysis. Inter-observer variability was inferred by comparing area under the ROC curve (AUCs) across institutions. Simplified PASS systems were developed based on multivariable analysis of key histopathological parameters. Results: The PASS system was a significant predictor of adverse events and recurrence-free survival. Although the PASS system demonstrated only modest discriminative ability (AUC, 0.673), it showed a high negative predictive value (NPV, 0.885), supporting its usefulness as a screening tool for benign behavior. However, there was significant inter-institutional variability in PASS performance (AUC; range, 0.513 to 0.727; p < .05). The 3-factor Simple PASS, which incorporates necrosis, spindling, and mitotic figures, exhibited less inter-observer variation. The 4-factor Simple PASS, which adds vascular invasion to the 3-factor model, also showed reduced inter-observer variability and improved AUC and NPV compared to the original PASS system. Conclusions: In this multicenter cohort, the PASS system demonstrated high NPV and screening potential, but significant inter-observer variability remains a challenge. Simplification of the PASS system and enhanced pathologist training may improve reproducibility and clinical utility in PPGL risk stratification.

This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.

Recurrent difficulty securing emergency department (ED) acceptance and delayed interfacility transfer, often resulting in multiple sequential transfer attempts (“round-robin” hospital seeking), in the Republic of Korea reflect a patient safety failure across the emergency care continuum, spanning Emergency Medical Services from emergency calls and prehospital care to ED stabilization, definitive treatment, and secondary transfer. We argue that the governance split between the National Fire Agency–led prehospital response and the Ministry of Health and Welfare–led emergency medical system fragments accountability and data, undermining sustainable quality management. We describe a “double bind” in which clinicians face medico-legal risk regardless of acceptance decisions, distorting transfer behavior. We propose an outcome-linked Quality Improvement system—integrated metrics, interoperable data linkage, operational medical control, and routine feedback—to strengthen Continuity of Patient Care. This requires functional integration of the dual command structure; transferring ambulance service functions to the Ministry of Health and Welfare, or an equivalently strong joint-governance model, should be evaluated. Regionally, responsibility-based systems should be implemented through councils that set transfer principles and resource allocation, supported by stable financing and performance review, with the regional emergency medical situation room providing medical control and real-time coordination. For mass-casualty incidents, preparedness should align standardized triage, integrated command and communication, training, and after-action review. Legal reform is a necessary starting point, but trust and sustained patient safety depend more on cultivating a learning-oriented safety culture grounded in patient experience and public deliberation throughout policy design and implementation.

Myopia, particularly high myopia, is a significant risk factor for several ocular pathologies including cataract, glaucoma, and retinal detachment. Excessive axial elongation associated with high myopia can induce biomechanical stretching, increasing the risk of serious complications like posterior staphyloma and myopic maculopathy. Global meta-analyses estimate that approximately 10 million people were visually impaired due to myopic maculopathy in 2015, with 3 million being blind. Recent nationwide surveys in South Korea revealed a prevalence of 65.4% for myopia and 6.9% for high myopia in children and adolescents, highlighting the urgent need for effective management. Delaying the onset and slowing the progression of myopia during childhood and adolescence is crucial for reducing the potential lifetime risk of these complications. This consensus statement, prepared by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus (KAPOS), reviews the current evidence for myopia control interventions and provides management strategies applicable to the South Korean clinical setting. Key interventions covered include lifestyle modifications (outdoor time, near work adjustment), optical methods (myopia-control spectacle lenses, dual-focus soft contact lenses, orthokeratology), and pharmacologic treatment (low-concentration atropine), as well as combination therapies. The statement also addresses patient selection, treatment outcome evaluation using spherical equivalent and axial length changes, and the crucial aspects related to treatment cessation and the rebound effect.

Objective: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy (ET) constitute the standard systemic treatment for estrogen receptor-positive, human epidermal growth factor 2-negative (ER+/HER2-) metastatic breast cancer (MBC). However, treatment responses remain heterogeneous, highlighting the need for reliable prognostic markers. This study aimed to evaluate the prognostic significance of 18F-fluorodeoxyglucose (FDG) PET/CT findings in this setting. Materials and Methods: This retrospective single-center cohort study included patients with ER+/HER2- MBC who underwent18F-FDG PET/CT before initiating CDK4/6 inhibitors plus ET between 2018 and 2023. Maximum standardized uptake value(SUVmax), whole-body metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured. Progression-free survival (PFS) and overall survival (OS) were evaluated as the primary and secondary outcomes, respectively, using multivariable Cox models. PET parameters (SUVmax, MTV, and TLG) were analyzed as both continuous and dichotomized variables based on median values, adjusting for relevant clinical covariates. Results: Among the 374 patients, 82 (21.9%) presented with de novo metastatic disease, and 357 (95.5%) received CDK4/6 inhibitors as first-line therapy. In multivariable Cox analysis, all continuous PET parameters were independently associated with PFS (adjusted hazard ratio for SUVmax 1.05 [95% confidence interval 1.02–1.08]; log-transformed MTV 1.16 [1.08–1.25]; and log-transformed TLG 1.14 [1.07–1.23]) and OS (SUVmax 1.08 [1.04–1.11]; log-transformed MTV 1.24 [1.12–1.38]; and log-transformed TLG 1.22 [1.11–1.34]) with all P < 0.001. Results based on dichotomized PET parameters were similar to those obtained with continuous values: PFS (adjusted hazard ratio for SUVmax ≥ 7.6, 1.41 [1.08–1.85]; MTV ≥ 21.2 cm 3 , 1.41 [1.08–1.86]; and TLG ≥ 78.9, 1.51 [1.14–1.99]) with P ≤ 0.013 and OS (1.43 [1.01–2.04]; 1.84 [1.28– 2.66]; and 1.73 [1.20–2.50], respectively) with P ≤ 0.046. Conclusion Pretreatment 18F-FDG PET/CT parameters are independent prognostic markers in patients with ER+/HER2- MBC receiving CDK4/6 inhibitors with ET, supporting their potential utility in risk stratification.

BACKGROUND/OBJECTIVES: The illustrated Healthy Eating Practice Questionnaire (HEPQ) was previously developed to assess food preferences, eating behaviors, hand/oral hygiene practices, and nutrition knowledge among Korean preschool children. Nevertheless, the lack of an integrated scoring system has limited its interpretability. This study developed a scoring system and a web-based platform with tailored feedback using a child-parent dyad approach. SUBJECTS/METHODS: The development process consisted of 5 phases: 1) questionnaire preparation for online use, 2) formulation of the scoring system, 3) determination of the cut-off values for three levels of healthy eating practices based on a child-parent survey, 4) technical development of the online platform, and 5) usability evaluation. A scoring system was established by standardizing the domain scores to a 100-point scale. One hundred child– parent pairs participated in the survey to calculate the Healthy Eating Practice Score (HEPS) and determine cut-off values for the HEPS levels. The validity of the cut-off values was examined by a comparison with the Nutrition Quotient for Preschoolers (NQ-P). A web-based platform was developed, and 47 child–parent pairs were used to assess its usability. RESULTS: Significant positive correlations were observed between child and parent HEPS across all domains. The HEPS-based classification showed good discriminative ability because higher HEPS levels were consistently associated with higher NQ-P scores in children and parents. The web-based HEPQ was easy to use and understand, and almost all participants (97.9% of children and 93.6% of parents) reported no difficulties using the platform. CONCLUSION The web-based HEPQ platform with an integrated scoring system provides a valid, user-friendly tool for assessing and interpreting healthy eating practices in preschool children. This platform supports parental engagement in children’s healthy eating practices and provides a practical tool for evaluating the effectiveness of nutrition education in early childcare settings.