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.

This study was conducted to identify educational needs for infection prevention and control (IPC) among staff in long-term care hospitals and to determine education priorities using the Borich model, importance-performance analysis (IPA), and the Locus for Focus (LFF) model. Methods: A descriptive crosssectional survey was conducted with 162 staff members from two long-term care hospitals in Gyeongsangbuk-do, Republic of Korea (January 5 to 16, 2026). A 32-item instrument across eight IPC domains was developed and refined based on the fourth cycle long-term care hospital accreditation standards and the national healthcareassociated infection surveillance manual. Participants rated the importance and perceived performance of each item. Data were analyzed using descriptive statistics, paired t-tests, Borich need scores, IPA, and LFF, with crosshairs based on the overall mean values. Results: Across all eight IPC domains, importance scores exceeded performance scores in both healthcare professionals and allied health personnel. At the domain level, priorities varied by occupation: overall, standard precautions and transmission-based precautions were the highest priorities. Among healthcare professionals, transmission-based precautions ranked first, followed by standard precautions, whereas among allied health personnel, standard precautions and multidrug-resistant organisms (MDRO) and antibiotic stewardship were identified as top priorities. Conclusion: IPC education in long-term care hospitals should be delivered as an integrated, role- and competency-based training system that standardizes facility-wide core practices-particularly standard precautions and transmission-based precautions-while providing job-specific advanced modules aligned with occupational scope and work processes, and should be supported by organizational measures such as monitoring, feedback, and ensuring access to IPC resources.

Background: and Purpose: To assess the long-term effectiveness, safety, and economic viability of recently approved Alzheimer’s disease (AD) therapies, as well as to evaluate the real-world application of novel diagnostics among AD patients with diverse comorbidities, comprehensive real-world data (RWD) analysis is essential. The Korean JOint RegistrY for ALZheimer’s Treatment and Diagnostics (JOY-ALZ) endeavors to create a registry of RWD derived from clinical practice on new diagnostic methods and therapeutic agents for AD introduced in Korea since 2021. Methods: Participants must fulfill all the following: 1) be at least 19 years old; 2) be actively receiving, scheduled to initiate, or undergoing evaluation for any AD disease-modifying treatment; 3) have completed amyloid positron emission tomography or cerebrospinal fluid AD immunoassay (a positive result is not essential for participation); 4) have a clinical classification of cognitively unimpaired, mild cognitive impairment, or probable AD dementia. Data generated during routine care is segmented into a minimum dataset, extended dataset, and research-only dataset requiring extra consent. Assessments encompass clinical, cognitive, functional, neurobehavioral, neuroimaging, and biomarker evaluations, in addition to systematic monitoring of new AD treatments and their safety.Data are collected and monitored at baseline, at semiannual intervals during the initial 2 years, and then annually up to 2034. To date, 46 medical centers will participate in JOY-ALZ. Conclusions JOY-ALZ is expected to promote understanding of the long-term clinical outcomes, safety, and cost-effectiveness of recently introduced diagnostics and treatments for AD, thereby supporting the progress of precision medicine in AD care and diagnosis.

Background: Nonalcoholic fatty liver disease, a progressive condition caused by the accumulation of fat in the liver, begins with simple steatosis and can potentially progress to metabolic dysfunction-associated steatohepatitis (MASH) in the presence of inflammation and fibrosis, ultimately leading to cirrhosis or hepatocellular carcinoma. Increasing evidence indicates that sodiumglucose cotransporter 2 (SGLT2) inhibitors effectively alleviate MASH in mouse models. However, there is a lack of research on the effects of enavogliflozin on liver disease. In the present study, we investigated the effects of SGLT2 inhibitors on MASH induced by a high-fat, high-cholesterol (HFHC) diet in mice. Methods: Male C57BL/6 mice were fed a normal chow diet, HFHC diet, or HFHC diet with enavogliflozin for 12 weeks. LX-2 and HepG2 cells were treated with enavogliflozin in the presence of various pathological stimuli. Results: The HFHC diet induced excessive hepatic lipid accumulation, inflammation, and severe fibrosis. Administration of enavogliflozin not only ameliorated hepatic steatosis and fibrotic conditions but also suppressed the production of inflammatory cytokines. Positive outcomes were also observed in in vitro experiments, where enavogliflozin demonstrated the ability to impede the activation of hepatic stellate cells and alleviate lipid accumulation in hepatocytes. The potential pathway through which enavogliflozin attenuated liver fibrosis development may be associated with the transforming growth factor β1/Smad signaling pathway. Conclusion Our results suggest that enavogliflozin is effective in a mouse model of MASH by attenuating hepatic steatosis, suppressing inflammation, and improving liver fibrosis.

BACKGROUND: Exogenous Cushing’s syndrome, which results from prolonged glucocorticoid treatment, is associated with metabolic abnormalities. Previously, we reported the inhibitory effect of tonsil-derived mesenchymal stem cell conditioned medium (T-MSC CM) on glucocorticoid signal transduction. In this study, we investigated the therapeutic efficacy of T-MSCs in a mouse model of exogenous Cushing’s syndrome. METHODS: Exogenous Cushing’s syndrome model mice was generated by corticosterone administration in the drinking water for 5 weeks, and T-MSCs were injected intraperitoneally twice during the third week. Serum lipid profiles were measured using a chemistry analyzer. HepG2 cells were treated with dexamethasone and co-cultured with T-MSCs.Expression levels of genes involved in cholesterol metabolism were examined using real-time PCR. Low-density lipoprotein receptor (LDLR) protein levels were determined using western blotting and immunohistochemistry. Liver RNA extracted from the CORT and CORT ? MSC mouse groups was used for transcriptome sequencing analysis and protein– protein interaction analysis. RESULTS: Weight reduction and improvements in dyslipidemia by T-MSC administration were observed only in female mice. T-MSCs reduce circulating LDL cholesterol levels by downregulating liver X receptor a (LXRa) and inducible degrader of LDLR (IDOL) expression, thereby stabilizing LDLRs in the liver. Transcriptome analysis of liver tissue revealed pathways that are regulated by T-MSCs administration. CONCLUSION Administration of MSCs to female mice receiving chronic corticosterone treatment reduced the circulating LDL cholesterol level by downregulating the LXRa–IDOL axis in hepatocytes. These results suggest that T-MSCs may offer a novel therapeutic strategy for managing exogenous Cushing’s syndrome by regulating cholesterol metabolism.

BACKGROUND: Exogenous Cushing’s syndrome, which results from prolonged glucocorticoid treatment, is associated with metabolic abnormalities. Previously, we reported the inhibitory effect of tonsil-derived mesenchymal stem cell conditioned medium (T-MSC CM) on glucocorticoid signal transduction. In this study, we investigated the therapeutic efficacy of T-MSCs in a mouse model of exogenous Cushing’s syndrome. METHODS: Exogenous Cushing’s syndrome model mice was generated by corticosterone administration in the drinking water for 5 weeks, and T-MSCs were injected intraperitoneally twice during the third week. Serum lipid profiles were measured using a chemistry analyzer. HepG2 cells were treated with dexamethasone and co-cultured with T-MSCs.Expression levels of genes involved in cholesterol metabolism were examined using real-time PCR. Low-density lipoprotein receptor (LDLR) protein levels were determined using western blotting and immunohistochemistry. Liver RNA extracted from the CORT and CORT ? MSC mouse groups was used for transcriptome sequencing analysis and protein– protein interaction analysis. RESULTS: Weight reduction and improvements in dyslipidemia by T-MSC administration were observed only in female mice. T-MSCs reduce circulating LDL cholesterol levels by downregulating liver X receptor a (LXRa) and inducible degrader of LDLR (IDOL) expression, thereby stabilizing LDLRs in the liver. Transcriptome analysis of liver tissue revealed pathways that are regulated by T-MSCs administration. CONCLUSION Administration of MSCs to female mice receiving chronic corticosterone treatment reduced the circulating LDL cholesterol level by downregulating the LXRa–IDOL axis in hepatocytes. These results suggest that T-MSCs may offer a novel therapeutic strategy for managing exogenous Cushing’s syndrome by regulating cholesterol metabolism.

Purpose: This study investigated the impact of nusinersen on health-related quality of life (HRQoL), functional performance, and caregiver burden in patients with infantile-onset spinal muscular atrophy (SMA), addressing a growing interest in disease-modifying treatments. Methods: A 14-month observational study was conducted to evaluate changes in HRQoL and functional performance using the Pediatric Quality of Life Inventory (PedsQL) Infant Scales and the Pediatric Evaluation of Disability Inventory Computer Adaptive Test (PEDI-CAT). Caregiver burden was assessed through the Assessment of Caregiver Experience with Neuromuscular Disease (ACEND). Motor function was evaluated using the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND). Correlations between CHOP INTEND scores, functional performance, and caregiver burden were analyzed. Results: Eight patients with infantile-onset SMA and their caregivers participated, with a median treatment initiation age of 4.6 months (range, 1.1 to 15.1). CHOP INTEND scores showed significant improvement (P<0.001), whereas all PedsQL Infant Scale scores declined. Conversely, the PEDI-CAT revealed significant enhancements in daily activities, mobility, and social-cognitive domains (all P<0.001). Caregiver burden lessened across most dimensions (P<0.001), with the exception of the time-related burden (P=0.731). Higher CHOP INTEND scores correlated with improvements in PEDI-CAT domains and a reduction in caregiver burden related to sitting/play and transfer activities. Conclusion The study demonstrates the positive effects of nusinersen on functional performance and caregiver burden in patients with infantile-onset SMA. However, discrepancies were observed in HRQoL outcomes, suggesting a need for further research that includes SMA-specific outcome measures to comprehensively assess the treatment's impact on patients' lives.

Purpose: This study investigated the impact of nusinersen on health-related quality of life (HRQoL), functional performance, and caregiver burden in patients with infantile-onset spinal muscular atrophy (SMA), addressing a growing interest in disease-modifying treatments. Methods: A 14-month observational study was conducted to evaluate changes in HRQoL and functional performance using the Pediatric Quality of Life Inventory (PedsQL) Infant Scales and the Pediatric Evaluation of Disability Inventory Computer Adaptive Test (PEDI-CAT). Caregiver burden was assessed through the Assessment of Caregiver Experience with Neuromuscular Disease (ACEND). Motor function was evaluated using the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND). Correlations between CHOP INTEND scores, functional performance, and caregiver burden were analyzed. Results: Eight patients with infantile-onset SMA and their caregivers participated, with a median treatment initiation age of 4.6 months (range, 1.1 to 15.1). CHOP INTEND scores showed significant improvement (P<0.001), whereas all PedsQL Infant Scale scores declined. Conversely, the PEDI-CAT revealed significant enhancements in daily activities, mobility, and social-cognitive domains (all P<0.001). Caregiver burden lessened across most dimensions (P<0.001), with the exception of the time-related burden (P=0.731). Higher CHOP INTEND scores correlated with improvements in PEDI-CAT domains and a reduction in caregiver burden related to sitting/play and transfer activities. Conclusion The study demonstrates the positive effects of nusinersen on functional performance and caregiver burden in patients with infantile-onset SMA. However, discrepancies were observed in HRQoL outcomes, suggesting a need for further research that includes SMA-specific outcome measures to comprehensively assess the treatment's impact on patients' lives.