Background: Epidermal growth factor (EGF) is widely applied in dermatology for its regenerative effects; however, its clinical utility is limited by low stability and high production costs.To overcome these limitations, we developed a novel probiotic-derived epidermal growth factor (pEGF) by engineering Pediococcus pentosaceus CBT SL4 to express and secrete EGF. Objective: To investigate the anti-photoaging effects of topical pEGF in a ultraviolet B (UVB)-irradiated mice by assessing histological and molecular changes related to collagen synthesis, extracellular matrix (ECM) remodeling, oxidative stress, and inflammation. Methods: SKH1 hairless mice were exposed to UVB for twelve weeks to induce photoaging and treated with topical 10% pEGF cream from week 9 to 12. Skin samples were analyzed using dermoscopy, histology, immunohistochemistry, quantitative real-time polymerase chain reaction, western blotting, and proteomics to evaluate morphological and molecular alterations in ECM components and inflammatory markers. Results: Topical pEGF treatment improved skin texture and reduced wrinkles. Histological evaluation revealed that EGF significantly attenuated UVB-induced epidermal thickening and restored collagen density, with the strongest effects observed in the pEGF group. Molecular analysis showed downregulation of matrix metalloproteinases (MMPs; MMP-1, MMP-3), upregulation of collagen (type I collagen, type III collagen) and tissue inhibitors of metalloproteinases (TIMPs; TIMP-1, TIMP-2). Additionally, pEGF reduced pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β) and oxidative stress markers. Conclusion pEGF demonstrated potent anti-photoaging effects through ECM restoration, inflammation modulation, and barrier reinforcement. These findings support the therapeutic potential of pEGF as a stable, cost-effective alternative to conventional EGF in dermatological applications.

Purpose: Human epidermal growth factor receptor 2 (HER2) is amplified or overexpressed in various malignancies, including breast and gastric cancers, and is associated with poor prognosis. Although HER2-targeted therapies, such as trastuzumab, improve outcomes in HER2-positive tumors, resistance often develops, and HER2-low tumors remain largely untargeted. Trastuzumab deruxtecan (T-DXd; DS-8201a) is a HER2-targeted antibody-drug conjugate with potent activity in HER2-positive and HER2-low tumors. This study evaluates its antitumor mechanisms and efficacy in HER2-positive, HER2-low, and homologous recombination deficiency (HRD)–associated models. Materials and Methods: Effects of T-DXd were assessed in cancer cell lines with diverse HER2 expression and HRD status. In vivo efficacy was evaluated using a xenograft model derived from HER2-low SNU-601 gastric cancer cells. Results: T-DXd reduced HER2 phosphorylation and downstream signaling (AKT, ERK) in HER2-positive cells. It induced DNA damage accumulation, as evidenced by increased γH2AX and p-Chk1 expression, and triggered apoptosis through cleaved poly(ADP-ribose) polymerase and caspase-3 activation, confirmed by annexin V staining. Similar effects were observed in HER2-low cells, with greater sensitivity in HRD cells. In xenografts, T-DXd reduced tumor volume by up to 80% at 4 mg/kg and 10 mg/kg. Histological analyses showed decreased Ki-67 and increased apoptosis. Furthermore, T-DXd induced G2/M cell cycle arrest and nuclear anaplasia, suggesting disruption of chromosomal stability as a potential antitumor mechanism. No significant toxicity, including body weight loss, was observed. Conclusion These findings highlight T-DXd’s effectiveness in HER2-low and HRD tumors, supporting its broader clinical application, including strategies targeting DNA damage repair pathways.

Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

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.

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.

Objectives: Assessing healthcare quality at the national level is essential for evaluating health system performance and identifying areas requiring improvement. This study examined long-term trends in healthcare quality in Korea from 2008 to 2023 using internationally comparable indicators. Methods: We conducted a trend analysis of healthcare quality in Korea using the Organization for Economic Cooperation and Development (OECD) Health Care Quality and Outcomes framework and quality indicators. Indicators across multiple domains, including acute care, primary care, prescribing in primary care, mental healthcare, and patient experiences, were analyzed and compared with OECD averages. Results: Healthcare quality in Korea improved across several domains. Thirty-day mortality for acute myocardial infarction decreased from 14.2% in 2008 to 10.2% in 2023, while mortality for ischemic stroke declined from 8.7% to 5.5%. Avoidable hospitalizations decreased substantially, with hospitalizations for chronic obstructive pulmonary disease declining by 59.7%. The proportion of patients with diabetes receiving cholesterol-lowering treatment increased from 44.1% to 82.5%. However, the proportion of broad-spectrum antibiotic prescriptions remained substantially higher than the OECD average (40.3 vs. 15.5%). In mental healthcare, excess mortality ratios increased from 4.3 in 2010 to 4.9 in 2023 for schizophrenia and from 3.5 to 4.3 for bipolar disorder, while post-discharge suicide rates showed little improvement. Patient experience indicators related to patient-physician communication improved and approached OECD averages. Conclusions Healthcare quality in Korea improved substantially between 2008 and 2023, particularly in acute care outcomes and chronic disease management. However, persistent challenges remain in areas such as antibiotic use, polypharmacy, and mental healthcare. These findings provide internationally comparable evidence to inform future health policy and healthcare quality improvement efforts.

Background: The prevalence of diabetes mellitus and early-onset dementia (EOD), defined as dementia diagnosed at an age <65 years, is increasing worldwide, with significant socioeconomic implications. We investigated the association between diabetes, prediabetes, and EOD, focusing on the influence of diabetes duration on EOD risk. Methods: Using the Korean National Health Insurance Service database, we analyzed data from 1,979,509 patients aged 40–60 years who underwent health checkups in 2009. Patients were categorized into five groups: normal, impaired fasting glucose (IFG), newly diagnosed diabetes, diabetes duration <5 years, and diabetes duration ≥5 years. Cox proportional hazard models were used to estimate the adjusted hazard ratios (aHRs) for EOD after adjusting for demographic and clinical covariates. Results: During the observation period (mean 7.75 years), 8,921 patients with EOD were identified. The diabetes group demonstrated a significantly higher incidence of EOD compared to the normal group (aHR, 1.334; 95% confidence interval [CI], 1.226 to 1.451). EOD risk increased with longer diabetes duration, with the highest risk observed in patients with diabetes ≥5 years (aHR, 1.543; 95% CI, 1.368 to 1.741). No significant difference was observed between the IFG and normal groups (aHR, 0.989; 95% CI, 0.938 to 1.043). Additionally, the hypertension group exhibited a significantly higher incidence of EOD compared to the non-hypertension group (aHR, 1.364; 95% CI, 1.291 to 1.442). Conclusion Diabetes is independently associated with increased risk of EOD, and this risk increases with longer diabetes duration. This association remained significant regardless of the presence and duration of hypertension.

Purpose: This study aimed to develop and implement an antimicrobial stewardship education program for physician assistant nurses and to evaluate its effects on their knowledge and clinical performance. Methods: A quasi-experimental, single-group pre-post design was conducted with 50 physician assistant nurses at a university hospital in Seoul, Republic of Korea. The antimicrobial stewardship education program, developed using the ADDIE model, consisted of 12 sessions including lectures and case-based learning (CBL)-based discussions.Knowledge was measured before and immediately after the intervention, while performance was assessed pre-intervention and four weeks post-program. Data were analyzed using paired t-tests, Wilcoxon signed-rank tests, and analysis of covariance (ANCOVA). Results: Knowledge scores significantly improved from 44.65±7.45 to 58.50±10.11 (p<.001), and all subdomains showed significant increases (p<.001). Performance scores increased from 3.68±0.77 to 4.28±0.68 (p<.001). Knowledge gain did not differ significantly between the medical and surgical departments (p=.710). Likewise, after adjusting for pre-test scores, no significant difference in performance improvement was observed between the two departments (ANCOVA, p=.170). These results indicate that the program was effective across both departments regardless of their characteristics. Conclusion The antimicrobial stewardship education program improved both knowledge and performance among physician assistant nurses. This program may contribute to the standardization of antimicrobial stewardship education and to appropriate antimicrobial use and the reduction of antimicrobial resistance.

Objective: This study aimed to evaluate the survival of removable partial dentures (RPDs) abutment teeth that had undergone root canal treatment (RCT) and to identify the factors influencing survival. Materials and Methods: Records from the Veterans Health Service Medical Center were reviewed to identify patients who received RPDs between 2014 and 2015 and had root canal-treated abutment teeth. Preoperative variables included patient demographics, tooth location, and periapical radiolucency, while postoperative variables included RPD classification, opposing dentition, crown-root ratio (CRR), root canal filling quality, post placement, and restoration type. Statistical analysis was performed using the Kaplan-Meier method and Cox proportional hazards models. Results: A total of 776 root canal-treated abutment teeth from 341 patients using RPDs (mean age, 72.03 years) were included. In the multivariate analysis, tooth-related conditions such as arch type and tooth location, presence of a periapical lesion, and presence of a core were significantly associated with poor prognosis. Kaplan-Meier survival analysis revealed that the 3-, 5-, 7-, and 10-year survival rates for all teeth were 93.5%, 84.4%, 77.1%, and 60.0%, respectively. Conclusion Arch type and tooth position, preoperative periapical radiolucency, and type of restoration are significantly associated with prognosis in patients with RPDs in whom the abutment teeth have previously undergone RCT.

Objective: Medication adherence is crucial for long-term outcomes in bipolar disorder. Despite the rising use of aripiprazole, a longacting injectable for bipolar disorder, once monthly to improve adherence and manage side effects, research on its effects in South Korean patients with bipolar disorder is limited. Methods: In this non-interventional, retrospective study, medical records were used to analyze aripiprazole once monthly treatment from its initiation in routine clinical settings. The data were collected at 1, 3, 6, 9, and 12 months. Functional level and symptom severity were measured using the Global Assessment of Functioning (GAF), Clinical Global Impression–Bipolar–Severity (CGI-BP-S), Young Mania Rating Scale (YMRS), Korean version of the Montgomery–Åsberg Depression Rating Scale (K-MADRS), and Hamilton Anxiety Rating Scale (HAM-A). Additionally, the dosages and number of pills of mood stabilizers and antipsychotics, and the total number of medications, were recorded. Results: Among 24 patients with bipolar disorder, significant functional improvement and symptom relief were observed over 1 year, with a significant reduction in total pill count and dosages of mood stabilizers and antipsychotics. Specifically, the GAF score increased by 25.7% (p=0.001), while CGI-BP-S, YMRS, K-MADRS, and HAM-A scores decreased by 24.4% (p=0.001), 81.2% (p=0.001), 36.2% (p=0.002), and 36.1% (p=0.003), respectively. Six patients reported side effects such as akathisia, tremors, weight gain, and headache, but no severe adverse effects were noted. Conclusion This study showed significant improvement in functional outcomes and mood symptoms with monthly aripiprazole treatment in bipolar disorder. Mood stabilizer and antipsychotic dosages were also reduced. The results highlight the proactive role of longacting injectable antipsychotics in enhancing functioning, symptoms, and quality of life in bipolar disorder.