Objective: Cognitive impairment is common in patients with Parkinson’s disease (PD), and few pharmacological options are available for treating this condition. We evaluated the effects of a digital cognitive training program (SUPERBRAIN), which was previously shown to be effective in populations at risk of Alzheimer’s disease, on cognitive function in individuals with PD. Methods: Twenty-three individuals with PD and mild cognitive impairment (PD-MCI) from four clinics were randomized to the intervention (n=16) or control (n=7) groups. The intervention group completed a 12-week, home-based, tablet-based cognitive training program (25–30 min/day, 7 days/week). Cognitive outcomes were assessed using the Seoul Neuropsychological Screening Battery pre- and post-intervention. Results: The adherence rate was 79.36%. The intervention group showed significant improvements in the Seoul Verbal Learning Test (SVLT) delayed recall and the Controlled Oral Word Association Test, while no changes were observed in the control group. Analysis of covariance confirmed greater SVLT improvement in the intervention group (F statistic=7.15, p=0.015, partial η2=0.28). Conclusion SUPERBRAIN is feasible and can improve cognitive function in individuals with PD-MCI.

Background: To evaluate the association between pulmonary hypertension and hospital admission rates in patients with bronchiectasis. Methods: We retrospectively analyzed data from 130 bronchiectasis patients at the National Medical Center, Korea (November 2012 to October 2022). Pulmonary hypertension was evaluated using high-resolution computed tomography (CT) and echocardiography. Patients were categorized into two groups based on the diameter of the main pulmonary artery (mPA). Logistic regression analysis was performed to identify risk factors associated with hospitalization. Results: Forty patients had suspected pulmonary hypertension on echocardiography. A higher percentage of patients with mPA diameter >29 mm (n=61) had a history of previous exacerbations, elevated echocardiographic parameters related to pulmonary hypertension, and reduced lung function, compared to those with mPA diameter ≤29 mm (n=69). In univariate analysis, the hospitalization group showed increased mPA diameter; pulmonary artery to aorta ratio; involvement of lung lobes, cavities, and nodules; and increased systolic pulmonary artery pressure and peak tricuspid regurgitation velocity. In multivariate analysis, mPA diameter >29 mm (adjusted odds ratio [OR], 2.47; 95% confidence interval [CI], 1.14 to 5.32) and the involvement of more than two lobes (adjusted OR, 2.57; 95% CI, 1.14 to 5.77) were significant risk factors for hospitalization. Conclusion The CT parameters demonstrated comparable accuracy to models that incorporated echocardiographic data to predict hospitalization in bronchiectasis patients.

Background: Catecholamines play a crucial role in muscle biogenesis, but their persistent elevation is linked to muscle wasting, which is poorly understood. This study aimed to investigate the association between catecholamine levels and age-related muscle loss. Methods: This retrospective study evaluated the plasma levels of two catecholamines, metanephrine and normetanephrine, and the clinical characteristics of 830 patients with adrenal incidentaloma on computed tomography (CT). Cross-sectional CT data at the L3 lumbar vertebrae were used to measure muscle areas. In vitro studies on C2C12 myotubes were conducted to examine β-adrenergic receptor signaling pathways and their role in myogenesis. Results: Men had significantly higher mean metanephrine levels of 0.17 nmol/L and normetanephrine levels of 0.63 nmol/L than women (P<0.05). Total abdominal muscle area was negatively correlated with catecholamine levels in both men and women, with the strongest negative correlation between normetanephrine levels and total abdominal muscle area in men (r=–0.31, P<0.001). Similarly, the strongest negative correlation between visceral fat area and metanephrine was observed in men (r=–0.25, P=0.004). Clenbuterol, a β-adrenergic receptor agonist, inhibited myogenesis, including myotube formation by extracellular signal-regulated kinase (ERK) suppression in C2C12 myoblasts. Conversely, β-blockers increased myogenesis via increasing ERK phosphorylation in C2C12 cells. These findings suggest that β-adrenergic modulation influences skeletal muscle differentiation, with ERK phosphorylation. Conclusion Catecholamine levels are associated with age, sex, muscle mass, and fat mass. Monitoring catecholamine levels, particularly in older men and in individuals with reduced muscle mass, may help manage age-related muscle loss and lead to individualized treatment strategies.

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.

Background: Rapid pathogen identification and antibiotic-susceptibility tests (ASTs) are important for treating bloodstream infections. We compared the performance of the QMAC-dRAST and BD Phoenix M50 direct AST (dPhoenix) systems using bacterial pellets prepared from positive blood culture broth and evaluated their impact on treatment modification. Methods: Direct AST results for 106 Enterobacterales isolates were retrospectively reviewed. Conventional broth microdilution was used to calculate categorical agreement (CA), very major error (VME), major error (ME), and minor error (mE). For isolates showing high VMEs in both methods, supplementary tests were performed. Clinical impact was evaluated by calculating the time required to obtain AST results (time-to-result) and observing changes in antibiotics prescribed after performing ASTs. Results: Both systems showed acceptable overall CA, VME, ME, and mE values (QMACdRAST: 93.6%, 1.6%, 0.9%, and 5.3%, respectively; dPhoenix: 93.1%, 0.9%, 0.6%, and 6.2%, respectively). Piperacillin–tazobactam showed high VMEs with QMAC-dRAST (4/20, 20.0%) and dPhoenix (3/20, 15.0%). Colony AST on 13 isolates revealed that QMACdRAST testing yielded lower minimal inhibitory concentrations (MICs) for piperacillin–tazobactam with three isolates, whereas dPhoenix testing yielded higher MICs with two isolates and lower MICs with two isolates. The average time-to-result was 20.8 hr and 30.1 hr for QMAC-dRAST and dPhoenix, respectively (P < 0.001). After AST, the number of optimal treatments increased from 43 (46.7%) to 72 (78.3%) (P < 0.001). Conclusions The QMAC-dRAST and dPhoenix systems provided reliable AST results with a short time-to-result. However, we recommend performing complementary tests, such as the disk diffusion test, for piperacillin–tazobactam.

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.

Purpose: Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative. Methods: As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers. Results: The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting. Conclusion This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.

Purpose: Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, necessitating the identification of novel therapeutic targets. The E3 ubiquitin ligase WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) has been implicated in various cancers, yet its specific role and underlying molecular mechanisms in CRC are poorly understood. This study aimed to investigate the functional role of WWP2 in CRC progression and to elucidate its regulatory mechanisms. Methods: WWP2 expression was evaluated in CRC patient tissues and cell lines using immunohistochemistry, quantitative real-time polymerase chain reaction, and western blotting. The biological functions of WWP2 were assessed using in vitro assays for cell proliferation, migration, and invasion following adenovirus-mediated overexpression. The molecular mechanism was investigated by analyzing the protein expression levels of p53 and its downstream target, p21, via western blot. An in vivo xenograft mouse model was used to confirm the oncogenic role of WWP2. Results: WWP2 expression was significantly upregulated in CRC tissues. Overexpression of WWP2 promoted CRC cell proliferation, migration, and invasion. Mechanistically, increased WWP2 expression led to a marked reduction in the protein levels of the tumor suppressor p53. Consequently, the expression of the p53 downstream target, the cell cycle inhibitor p21, was also suppressed. In the xenograft model, WWP2 overexpression significantly enhanced tumor growth. Conclusion Our findings demonstrate that WWP2 functions as an oncogene in CRC. It promotes cancer progression by destabilizing the tumor suppressor p53 and downregulating p21. This study highlights the WWP2-p53-p21 axis as a potential novel therapeutic target for CRC.

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.

Purpose: Older cancer patients face unique challenges due to age-related physiological changes, increasing their vulnerability to treatment-related toxicities. Geriatric assessment (GA) is a validated tool for optimizing care, yet there is no consensus on integrating geriatric interventions into oncology. This study evaluates the feasibility of a tailored onco-geriatric intervention model incorporating the KG-7 screening tool. Materials and Methods: This prospective study included 30 patients aged ≥ 70 years with solid tumors undergoing adjuvant or palliative chemotherapy. Patients scoring ≤ 5 of KG-7 were eligible. Tailored interventions incorporating KG-7 included polypharmacy, functional status, mobility, nutrition, cognition, emotional well-being, insomnia, social support, and medical problem. KG-7, GA, and quality of life (QoL) were followed at 12 weeks. Results: Participants (median age, 79.5 years) had colon (43.3%), pancreatic (23.3%), or gastric cancer (23.3%). At baseline, most patients showed independent activities of daily living (100%)/instrumental activities of daily living (90%). However, 93.3% had abnormal GA. Particularly, 86.7% were either malnourished or at risk of malnutrition. The most frequently identified intervention needs included polypharmacy (70.0%), nutritional support (60.0%), and emotional well-being (50.0%) with high adherence (100.0%, 88.9%, and 46.7%, respectively). At 12 weeks, KG-7 scores improved in 43.8% of patients, and 69.2% of GA domains were improved. QoL analysis revealed modest improvement in Global Health Status (mean difference, 6.3; p=0.176). One-year survival rates were 92.3% and 79.4% for adjuvant and palliative groups, respectively. Conclusion The onco-geriatric intervention model incorporating KG-7 demonstrated high feasibility and potential to enhance clinical outcomes. Future studies should validate this approach in randomized trials to optimize care for older cancer patients.