Purpose: This study aimed to develop and test a structural equation model of respiratory infection prevention behaviors among elementary school teachers based on the Information–Motivation–Behavioral Skills model. Methods: This study included 250 teachers who were currently working in elementary schools and had experience as homeroom teachers. Data were collected from December 18 to December 31, 2023 using self-reported questionnaires. The proposed model included school organizational culture as the exogenous variable and respiratory infection prevention knowledge, respiratory infection prevention attitude, social support, self-efficacy, and respiratory infection prevention behavior as endogenous variables. Data were analyzed using IBM SPSS for Windows ver. 24.0 and Smart PLS ver. 4.1. Results: Of the 19 hypothesized paths in the research model, five were statistically significant. School organizational culture had a significant direct effect on respiratory infection prevention knowledge (β=.20, p=.041), social support had a significant direct effect on self-efficacy (β=.33, p=.001), and self-efficacy had a significant direct effect on respiratory infection prevention behaviors (β=.22, p=.021). Respiratory infection prevention attitude (direct: β=.23, p=.029; total: β=.26, p=.008) and school organizational culture (direct: β=.22, p=.017; total: β=.30, p=.002) had significant direct and total effects on respiratory infection prevention behaviors. Conclusion To enhance respiratory infection prevention behaviors among elementary school teachers, interventions should focus on strengthening positive attitudes toward infection prevention and improving self-efficacy. Organizational-level strategies, including establishing supportive school organizational cultures, promoting peer support among teachers, and sharing infection prevention practices within schools, are also needed to facilitate and sustain preventive behaviors.

This review summarizes the establishment of the 2025 Dietary Reference Intakes for Koreans (KDRIs), the third national standard for nutrient reference values in Korea. The 2025KDRIs build on lessons from revisions in 2010, 2015, and 2020, and chart a path forward by addressing 4 priorities: upgrading the scientific evidence base through systematic evaluation, strengthening intake monitoring using national survey data, advancing international harmonization, and responding to changes in the nutrition and health environment, including those associated with the coronavirus disease 2019 (COVID-19) pandemic. The scientific basis of the KDRIs was advanced by systematically evaluating the findings across exposure indicators, health assessment indicators, and the health outcomes, and reorganizing the indicators to estimate the nutrient requirements. Adequate Intake was set using explicit criteria when an Estimated Average Requirement could not be derived, data gaps, uncertain outcomes, and limited representativeness were documented. Key inputs, including coefficients of variation and uncertainty factors, as well as life stage estimation procedures, were re-evaluated in alignment with current evidence and international standards. The 2025 KDRIs incorporate intake evidence from the Korea National Health and Nutrition Examination Survey to inform policy and practice and support intake monitoring. For international harmonization, the NUQUEST-based literature framework was updated, and recent DRIs from other countries were compared. The shifts in anthropometric characteristics and dietary intake patterns observed during the COVID-19 pandemic were considered to reflect a changing context. The review identified remaining challenges for future revisions, including validating Koreanspecific indicators, developing evidence for infants and older adults, stronger translation of reference values into policy and practice, prioritizing of nutrients for future review within the 5-year revision cycle. Together, these advances will position the 2025 KDRIs as a science-based national reference integrating policy, practice, and evidence to support implementation aimed at improving nutritional status and healthy life expectancy in Korea.

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.

Objective: To evaluate the performance of supplemental automated breast ultrasound (ABUS) added to mammography-based breast cancer screening for women with nondense breasts. Materials and Methods: A retrospective search of radiology databases at two tertiary institutions identified asymptomatic women with nondense breasts who underwent breast cancer screening using both digital mammography (DM) and supplemental ABUS between January 2020 and December 2023. We excluded women without sufficient follow-up data or those without an established final diagnosis, including histopathologic results. The performance measures of DM alone and ABUS combined with DM (ABUS plus DM) were compared. The primary outcome was the cancer detection rate (CDR), and the secondary outcomes were sensitivity and specificity. Subgroup analyses were performed for women with scattered fibroglandular density and almost entirely fatty breasts. Results: A total of 2,904 pairs of screening examinations were performed in 1,683 women (59 ± 10 years), detecting 26 cancers. In comparison with DM alone, ABUS plus DM showed higher CDR (9.0 vs. 7.9 per 1,000 examinations, P < 0.001), higher sensitivity (100% [26/26] vs. 88.5% [23/26], P < 0.001), and lower specificity (95.0% [2,735/2,878] vs. 97.9% [2,817/2,878], P < 0.001). In women with scattered fibroglandular density, ABUS increased the CDR from 7.4 to 8.5 per 1,000 examinations and improved the sensitivity from 87.0% [20/23] to 100% [23/23] (P < 0.001). In women with almost entirely fatty breasts, ABUS plus DM showed the same CDR (16.4 per 1,000 examinations) and sensitivity (100% [3/3]) as DM alone. Three cancers (11.5% [3/26]), all of which were stage T1N0, were detected only by supplemental ABUS. Conclusion Supplemental ABUS improved cancer detection and sensitivity in women with nondense breasts, with the benefits primarily observed in those with scattered fibroglandular density.

Purpose: Limited treatment options exist for patients with metastatic castration-resistant prostate cancer (mCRPC) after the failure of taxane-based chemotherapy and novel hormonal therapy. Here, we report the safety and efficacy of ifosfamide and mesna in patients with mCRPC after the failure of taxane-based chemotherapy and novel hormonal therapy (NCT06236789). Materials and Methods: Patients with histologically confirmed prostate cancer who had failed taxane-based chemotherapy and novel hormonal therapy received ifosfamide 2,500 mg/m2 and mesna 1,500 mg/m2 on days 1–3, repeated every 21 days. Safety, objective response rate, disease control rate, reduction in serum prostate-specific antigen (PSA) concentration by >50% (PSA50) or >90% (PSA90), radiographic progression-free survival (rPFS), and overall survival (OS) were analyzed. Results: A total of 47 patients with mCRPC were included in the study. The median number of lines of treatment was 5 (range, 3 to 7). All patients were previously administered docetaxel and novel hormonal therapies including abiraterone (51.1%) and/or enzalutamide (61.7%). Thirty-eight patients (80.9%) were administered cabazitaxel. The objective response and disease control rates were 21.3% and 80.9%, respectively. PSA50 and PSA90 were achieved in 31.9% and 10.6%, respectively. During a median follow-up duration of 54.3 months, rPFS and OS were 5.0 and 9.0 months, respectively. All the patients experienced treatment-related adverse events of any grades; however, no new safety signs were detected. Genomic biomarker analysis revealed that alterations in the TP53 pathway were associated with inferior rPFS and OS. Conclusion Ifosfamide and mesna showed appreciable efficacy and manageable safety profiles in heavily treated patients with mCRPC.

This study examined sleep-related characteristics among university students and the associations between sleep quality, dietary habits, and diet quality.Three hundred and ninety-three university students (206 men and 187 women) enrolled at universities in the Chungcheong region of Korea participated in this study between November and December 2023. Data on the general characteristics, dietary habits, sleep status, and the Nutrition Quotient (NQ) for adults were collected using a structured questionnaire. The sleep quality was assessed using the Pittsburgh Sleep Quality Index– Korean version (PSQI-K). The participants were classified into a good sleeper group (PSQI-K≤5) and a poor sleeper group (PSQI-K≥6). The dietary habits and NQ scores were compared according to the sleep quality. Compared with good sleepers, poor sleepers had a significantly higher prevalence of eating alone at least once per day (P<0.01) and higher scores for unhealthy dietary behaviors, including overeating, eating quickly, a preference for salty food, skipping meals, and irregular meal timing (P<0.05). Although the total NQ scores and balance and practice domain scores did not differ according to sleep quality, the moderation domain scores were significantly lower among poor sleepers, particularly in men (P<0.05). In conclusion, poor sleep quality among university students was associated with unhealthy dietary habits and lower diet quality related to dietary restraint. These findings highlight the importance of improving sleep quality as a part of health education and dietary intervention programs for university students.

Janus kinase (JAK) inhibitors are an important treatment option for ulcerative colitis, providing rapid onset of action, oral administration, and efficacy even after biologic failure. The 3 approved agents—tofacitinib, filgotinib, and upadacitinib—differ in JAK isoform selectivity, leading to clinically meaningful differences in efficacy and safety. Evidence from network meta-analyses, clinical trials, and real-world studies consistently shows that upadacitinib provides the highest efficacy for induction and maintenance of remission, whereas filgotinib demonstrates the most favorable safety profile. The strong efficacy of upadacitinib and tofacitinib is particularly relevant in patients with severe disease, including acute severe ulcerative colitis, and upadacitinib maintains high efficacy regardless of prior advanced therapy exposure. JAK inhibitors also benefit extraintestinal manifestations. Although risks such as herpes zoster, serious infection, thromboembolism, and major cardiovascular events differ among agents, long-term data suggest generally acceptable safety when used appropriately. Intraclass JAK-to-JAK cycling is feasible, with about half of patients achieving steroid-free clinical remission in retrospective cohorts. Based on mechanistic, clinical, and real-world evidence, filgotinib may be a first-line option for patients with lower disease activity or when safety is a priority, whereas upadacitinib or tofacitinib may be preferred in higher disease activity. Strategically selecting agents may improve durability and outcomes.

Objective: Patients with panic disorder (PD) are approximately four times more likely to experience suicidal thoughts and attempts compared to healthy controls (HCs). Despite the elevated risk compared to HCs, the relationship between cortical thickness (CT) in PD and suicidality remains underexplored. Methods: We recruited 161 right-handed participants, including 82 PD patients and 79 HCs, and assessed them using a comprehensive battery of psychological scales, including the Scale for Suicidal Ideation (SSI), Early Trauma Inventory Self Report-Short Form, Neuroticism-Extraversion-Openness Personality Inventory-Neuroticism (NEO-N), State-Trait Anxiety Inventory-Trait Anxiety (STAI-T), Panic Disorder Severity Scale (PDSS), and Beck Depression Inventory. Results: In whole-brain vertex-wise group comparison, patients with PD demonstrated significantly lower CT values in the insula, lateral occipital sulcus, and precentral gyrus compared to HCs. Notably, paradoxical significant positive correlations were observed between SSI total scores and CT in the above-mentioned regions within the PD cohort.Pearson’s correlation analyses further indicated that CT in these regions may be linked to high levels of early trauma, trait anxiety (e.g., NEO-N, STAI-T), panic symptom severity (e.g., PDSS), and treatment response in patients with PD. Conclusion This study suggest that suicidality in PD may be associated with CT in specific EFN regions related to suicidal brain and that CT in these regions could play a critical role in anxiety symptomatology in PD.

In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.