Background: This study was performed to establish a rabbit model for esophageal surgery in the treatment of cervical esophageal diseases. The necessary steps for postoperative treatment and esophageal examination were detailed. Methods: This study aimed to confirm the feasibility of the surgical procedure in rabbits and develop a postoperative management protocol. Six New Zealand White rabbits underwent esophagectomy and end-to-end anastomosis of the cervical esophagus under general anesthesia. Postoperatively, the rabbits were fed a specially formulated therapeutic liquid diet for 3 to 7 days. Recovery was monitored for 8 weeks, after which the rabbits were euthanized. Esophagography and endoscopy were conducted during the first postoperative week to assess healing. Results: Of the six rabbits that underwent surgery, two died from nonsurgical complications within 7 days after the operation. Of the remaining rabbits, two were diagnosed with esophageal stricture via esophagography and underwent endoscopy after the first postoperative week. The final two rabbits completed the 8-week postoperative period without complications. Conclusions Esophageal surgery and postoperative treatment in rabbits require careful attention. We anticipate that this study will provide valuable and practical information for researchers conducting esophageal studies using rabbits.

Idiopathic pulmonary fibrosis (IPF) is characterized by maladaptive epithelial–mesenchymal crosstalk and progressive extracellular matrix accumulation, whereas currently available antifibrotic agents merely decelerate functional decline.This study investigated whether exosomes derived from human mesenchymal stem cells derived from embryonic stem cells (ESC-MSCs) restore epithelial stress responses and attenuate fibrotic remodeling. Human IPF lung transcriptomes were integrated with a bleomycin-induced murine model analyzed by RNA sequencing and protein signaling, together with cigarette smoke extract-induced injury in A549 epithelial cells. ESC-MSCs-derived exosomes exhibited typical morphology and size distribution, enrichment of tetraspanins, and absence of endoplasmic reticulum contamination, consistent with high-purity preparations. Across human IPF and bleomycin-injured lungs, transcriptomic profiling revealed prominent enrichment of extracellular matrix and cytoskeletal gene programs, whereas mitogen-activated protein kinase (MAPK) and Smad families displayed only modest alterations at the mRNA level. In vivo administration of exosomes during the fibrotic remodeling phase, via either intravenous or intratracheal delivery, resulted in improved body weight, reduced lung weight-to-body weight ratios, and decreased collagen deposition and Ashcroft scores. These structural and functional improvements were accompanied by suppression of profibrotic and mesenchymal markers and selective attenuation of activator protein-1 (AP-1) activity. In epithelial injury models, ESC-MSCs-derived exosomes enhanced cell viability, restored redox homeostasis, and constrained stress-induced mesenchymal gene expression and MAPK phosphorylation in both co-treatment and post-treatment settings. Collectively, these data support an epithelial-centered mechanism in which ESC-MSCs-derived exosomes re-establish oxidative balance and selectively restrict AP-1-driven stress signaling, thereby secondarily limiting extracellular matrix accumulation and fibrotic remodeling.

Purpose: Based on the KEYNOTE-522 study, neoadjuvant pembrolizumab plus chemotherapy has become the standard treatment for early-stage triple-negative breast cancer (TNBC).This study evaluated the real-world efficacy, safety, and predictors of pathologic complete response (pCR) in Korean patients. Methods: We conducted a retrospective cohort study of 174 patients with early-stage TNBC who received the KEYNOTE-522 regimen (neoadjuvant pembrolizumab plus paclitaxel and carboplatin, followed by doxorubicin and cyclophosphamide) at a tertiary cancer center between August 2022 and July 2024. We assessed the primary endpoints, including pCR rate and event-free survival (EFS). We performed univariable and multivariable logistic regression analyses to identify independent predictors of pCR. Results: The median patient age was 50 years (range, 24–74 years). The clinical stages were II and III in 79.3% and 20.1% of patients, respectively, and 10.9% had clinical N3 disease. The overall pCR rate was 62.1%, and the N3 subgroup had a pCR rate of 47.4%. On multivariable analysis, high baseline Ki-67 expression (≥ median, 75%) was significantly associated with pCR (odds ratio, 2.84; 95% confidence interval, 1.45 to 5.66; p = 0.002). At a median followup of 18.4 months, the 12-month EFS rate was 97.4%, with significantly superior outcomes observed in patients who achieved pCR compared with those who did not achieve pCR (100% vs. 93.1%, p = 0.007). The treatment completion rate was 92.0%, and immune-related adverse events occurred in 13.8% of patients. Conclusion In this real-world analysis of one of the largest Asian cohorts of patients with earlystage TNBC treated with neoadjuvant pembrolizumab, the KEYNOTE-522 regimen demonstrated substantial efficacy and manageable toxicity, consistent with the original trial findings.

Background/Aims: The benefits of adjuvant therapy after curative resection (CR) have been demonstrated for bile duct cancer with lymph node (LN) metastasis. However, the putative benefits of adjuvant treatment for bile duct cancer without LN metastasis remain controversial.We aimed to identify recurrence risk factors for distal bile duct cancer (DBC) without LN metastasis following CR and high-risk groups that may benefit from adjuvant treatment. Methods: We retrospectively analyzed recurrence-related factors of patients who underwent surgical resection for DBC at Yonsei University Severance Hospital from January 2010 to June 2019. Results: Of 380 DBC cases receiving CR, 248 (62.8%) were pathologically confirmed as free from LN metastasis. The recurrence rates of all cases and LN metastasis-free cases were similar at 52.4% and 46.8%, respectively. Further, distant metastasis and local recurrence were about equally frequent. Involvement of adjacent organs, the presence of an R1 resection margin (cancer cells present microscopically), lymphovascular invasion (LVI), and perineural invasion (PNI) were identified as risk factors for recurrence (R1 margin OR: 1.642, 95% CI: 1.045–2.578, p = 0.031; LVI OR: 2.049, 95% CI: 1.347–3.115, p = 0.001; PNI OR: 1.901, 95% CI: 1.170–3.088, p = 0.009). Overall survival was also significantly reduced in patients with R1 resection margins (p = 0.018), LVI (p < 0.001), or PNI (p = 0.002). Conclusions The overall risk of LN-negative DBC recurrence remains high after CR. Aggressive systemic adjuvant treatment and active surveillance are required for patients with R1 resection margins, LVI, or PNI.

Purpose: This study aimed to identify factors influencing psychiatric nursing competency among emergency nurses and to examine the mediating role of psychological safety in the relationship between communication self-efficacy and psychiatric nursing competency. Methods: Data were collected from 157 emergency nurses in Korea between November 20 and December 17, 2025, using an online self-administered questionnaire. Data were analyzed using descriptive statistics, t-tests, one-way ANOVA, Pearson's correlation, hierarchical multiple regression, and mediation analysis based on Baron and Kenny's approach (IBM SPSS 27.0). Results: The mean score of psychiatric nursing competency was 3.25±0.31. Psychiatric nursing competency was positively correlated with communication selfefficacy and psychological safety, and communication self-efficacy was also positively correlated with psychological safety. Regression analysis showed that psychological safety (β=.43, p<.001), communication self-efficacy (β=.38, p<.001), and psychiatric nursing education experience (β=.21, p<.001) significantly influenced psychiatric nursing competency, explaining 52.6% of the variance. Psychological safety partially mediated the relationship between communication self-efficacy and psychiatric nursing competency. Conclusion Communication self-efficacy enhances psychiatric nursing competency through psychological safety, highlighting the need for integrated individual and organizational strategies.

Vaccines are highly effective, but rare or delayed adverse events following immunization (AEFIs) require post-licensure surveillance beyond clinical trials. Korea lacks a comprehensive, active, database-based framework, yet key assets exist: nationwide claims databases (National Health Insurance Service/Health Insurance Review and Assessment Service), the national immunization registry (Korea Disease Control and Prevention Agency’s Immunization Registry Information System) for National Immunization Program (NIP) and non-NIP vaccines, and increasingly standardized hospital electronic health records.We propose a federated, code to data architecture with data linkages between these data.Implementation should adopt a common data model (CDM), standardized case definitions, latency accounting, and transparent public reporting under strong privacy governance. Major challenges include multi step administrative approvals for data linkage, incomplete capture of adult non-NIP vaccinations, heterogeneous hospital data structures, and strict data protection constraints. Strategic priorities are to streamline statutory and administrative processes for public health use, mandate or enable claims-based capture of adult vaccinations, enhance CDM based interoperability, and develop secure hubs for aggregated outputs. With these measures, Korea will be well positioned to establish a scalable active surveillance system capable of detecting rare AEFIs, supporting transparent and evidence-based communication, and ensuring equitable injury compensation grounded in domestic data.

A unified consensus statement on medication-related osteonecrosis of the jaw (MRONJ) has not yet been established among the Asian member countries or regions of the Asian Federation of Osteoporosis Societies (AFOS). This study aimed to develop a consensus on MRONJ in patients with osteoporosis across these countries and regions. In this study, the term “Asia-Pacific” refers specifically to the Asian member countries and regions of AFOS. A structured survey consisting of nine MRONJ-related questions was distributed across 10 countries and regions to assess the level of agreement and summarize regional perspectives. In addition, a manual literature review and voting were conducted to evaluate the current evidence on MRONJ. The key aspects of MRONJ, including definition, staging, diagnosis, pathogenesis, risk factors, management, and prevention, were generally consistent among the AFOS countries and regions. The annual incidence and incidence rate of MRONJ associated with low-dose antiresorptive therapy in patients with osteoporosis ranged from 0.025% to 0.136% and 21 to 283 cases per 100,000 person-years, respectively. However, evidence regarding the benefits of drug discontinuation before dental surgery, such as tooth extraction, remains insufficient. Large-scale, multinational studies across AFOS countries and regions are warranted to determine the incidence of MRONJ better and evaluate the impact of antiresorptive drug discontinuation before dental procedures. These findings may contribute to the devel opment of effective evidence-based strategies for preventing MRONJ in patients with osteoporosis.

Dilated cardiomyopathy is the most common form of cardiomyopathy in children and often leads to irreversible myocardial dysfunction. To improve the prognosis, it is critical to identify rare but reversible causes. We report a 12-year-old girl referred to the emergency department for dyspnea on exertion and generalized edema that lasted for 1 month. She gained 20 kg over the past 3 years, which had gone uninvestigated. Transthoracic echocardiography demonstrated left ventricular dysfunction with pericardial effusion. Thyroid function tests revealed concentrations of free T4 and thyroid-stimulating hormone of 0.12 ng/dL (reference value, 0.93-1.7) and 86.9 µIU/mL (0.3-4.2), respectively, with anti-thyroid peroxidase and anti-thyroglobulin antibodies elevated, confirming the presence of autoimmune hypothyroidism. We initiated heart failure management alongside levothyroxine replacement therapy. After 5 months of treatment, a follow-up echocardiography showed improved left ventricular and thyroid function.

Neurodevelopmental disorders (NDDs) comprise a heterogeneous group of conditions characterized by impairments in cognition, language, motor function, behavior, and social communication that originate during the developmental period. Advances in neuroscience, genomics, and digital health have substantially transformed the current understanding of the mechanisms, diagnosis, and management of NDDs. This review summarizes the contemporary conceptual framework of NDDs, highlights advances in etiological diagnosis—particularly those related to genetic and genomic technologies—and discusses emerging therapeutic approaches, including digital therapeutics. Emphasis is placed on the importance of early identification, domain-based assessment, and precision medicine approaches to optimize long-term outcomes.

Background: Erythema multiforme (EM) is typically a self-limited, acute hypersensitivity reaction. However, a subset of patients experiences chronic, recurrent episodes, for which clinical features and treatment strategies differ depending on the underlying etiology, especially in herpes simplex virus (HSV)-associated cases. Objective: To investigate the clinical and phenotypic features of chronic recurrent EM and assess treatment responses, with a focus on differences based on HSV association. Methods: This retrospective study included pathology-confirmed cases of suspected EM from 2010 to 2023. Forty patients with chronic EM (≥3 recurrences or persistent disease for ≥12 months) were included. Clinical, histopathologic, and serologic data were analysed.Patients were stratified into herpes simplex virus-associated erythema multiforme (HAEM) and non-HAEM groups. Clustering analysis was performed to identify clinical phenotypes.Treatment responses to antivirals and immunomodulators were evaluated. Results: Of the 40 patients, 24 (60%) were classified as HAEM. HAEM patients showed more mucosal involvement, smaller targetoid lesions, and acral predominance, while nonHAEM patients had larger, coalescing lesions with more trunk involvement. Cluster analysis supported HSV as the major discriminating factor. Antiviral agents were effective in 87.5% of HAEM cases but ineffective in 76.9% of non-HAEM patients. Immunosuppressants such as cyclosporine and mycophenolate mofetil showed variable responses. Baricitinib induced complete remission in all 3 refractory cases. Conclusion HSV association defines a distinct clinical subtype of chronic recurrent EM, with differences in lesion morphology, distribution, and treatment response. Recognizing these patterns may guide targeted therapeutic strategies, including the potential use of Janus kinase inhibitors in refractory cases.