Objective To elucidate the molecular mechanism of sirtuin-3 (SIRT3) in regulating mitochondrial biogenesis in human renal tubular epithelial cells. Methods Cells were stimulated with different concentrations of H₂O₂ and divided into four groups: control (NC), 50 μmol/L H₂O₂, 110 μmol/L H₂O₂ and 150 μmol/L H₂O₂. SIRT3 protein expression was then measured. SIRT3 was knocked down with siRNA, and cells were further assigned to five groups: control (NC), negative-control siRNA (NCsi), SIRT3-siRNA (siSIRT3), NCsi+H₂O₂, and siSIRT3+H₂O₂. After 24 h, cellular adenosine triphosphate (ATP) and mitochondrial superoxide anion (O₂•⁻) levels were determined, together with mitochondrial expression of SIRT3, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), superoxide dismutase 2 (SOD2), acetylated-SOD2 and adenosine monophosphate activated protein kinase α1 (AMPKα1). Results The 110 and 150 μmol/L H₂O₂ decreased SIRT3 protein (both P<0.05). ATP and mitochondrial O₂•⁻ did not differ between NC and NCsi groups (both P>0.05). Compared to the NCsi group, the siSIRT3 group exhibited elevated O₂•⁻ level, decreased SIRT3 protein and increased expression levels of SOD2 and acetylated SOD2 protein (all P<0.05). Compared to the NCsi group, the NCsi+H₂O₂ group exhibited decreased cellular ATP levels, elevated mitochondrial O₂•⁻ levels, and reduced protein expression levels of SIRT3, SOD2, TFAM, AMPKα1, PGC-1α and NRF1 (all P<0.05). Compared with the siSIRT3 group, the siSIRT3+H₂O₂ group showed a decrease in cellular ATP levels, an increase in mitochondrial O₂•⁻ levels, a decrease in SIRT3, SOD2, TFAM, AMPKα1, PGC-1α and NRF1 protein expression levels and a decrease in acetylated SOD2 protein expression levels (all P<0.05). Compared with the NCsi+H₂O₂ group, the siSIRT3+H₂O₂ group showed a decrease in cellular ATP levels, an increase in mitochondrial O₂•⁻ levels, a decrease in SIRT3, AMPKα1, PGC-1α and NRF1, TFAM protein expression levels, and an increase in SOD2 and acetylated SOD2 protein expression levels (all P<0.05). Conclusions SIRT3 promotes mitochondrial biogenesis in tubular epithelial cells via the AMPK/PGC-1α/NRF1/TFAM axis, representing a key mechanism through which SIRT3 ameliorates oxidative stress-induced mitochondrial dysfunction.

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: Dual anti–human epidermal growth factor receptor 2 (HER2) drugs have become the standard regimen for neoadjuvant systemic treatment (NST) to HER2-positive breast cancer patients. However, the efficacy varies greatly among patients with different HER2 protein expression levels. Materials and Methods: A total of 575 HER2-positive breast cancer patients from multiple centers throughout China from 2013 to 2022 were retrospectively analyzed. We compared clinicopathological features in different HER2 immunohistochemistry classes (HER2 2+/in situ hybridization [ISH] + or HER2 3+), and their difference in response to NST and survival with single or dual anti-HER2 drugs. Drug sensitivity assays were used to evaluate different efficacy of anti-HER2 drugs in vitro. Results: Compared to HER2 3+ subgroup, the HER2 2+/ISH+ group had a higher proportion of hormone receptor–positive status (48.7% vs. 76.1%, p < 0.001), more HER2 protein loss after NST, lower pathological complete response (pCR) rate (46.07% vs. 16.24%, p < 0.001), and tended to have worse disease-free survival (DFS). In HER2 2+/ISH+ patients, treated with pertuzumab and trastuzumab in combination had no significant improvement in pCR (19.12% vs. 12.24%, p=0.287) and DFS (p=0.908) than using alone. Drug sensitivity assay showed poor efficacy with dual anti-HER2 drugs in HER2 2+/ISH+ cell lines; however, fam-trastuzumab deruxtecan drugs had a satisfactory effect. Conclusion Owing to the differences in clinicopathological features and treatment efficacy, we considered the HER2 2+/ISH+ group to be a distinct subtype and defined it as the HER2-moderate–positive subgroup. In this subgroup, dual anti-HER2 drugs did not exert significant improvement in pCR and DFS. Therefore, treatment optimization is warranted, with antibody-drug conjugate drugs as potential options.

Objective: Prolonged fasting has been reported to have a negative effect on patient outcomes. Although fasting is routinely practiced in the emergency department (ED), there is limited evidence on the current status and appropriateness of fasting in the ED. This study examined the status and appropriateness of fasting in the ED and identified the characteristics of patients who experienced unnecessary fasting. Methods: A retrospective observational study was performed at an urban ED in Seoul, Korea. The fasting status and characteristics of adult patients who visited the ED and were admitted or discharged between April 1 and April 30, 2022, were analyzed. A checklist for discontinuing fasting in the ED was used to screen for unnecessary fasting. Results: Among 2,292 patients who met the study inclusion criteria, all patients were instructed to begin fasting upon ED arrival. Fasting was discontinued by the physician’s order in 300 patients (13.1%). Patients remained fasting for 92.0%±23.2% of their total ED length of stay. Of the 1,577 patients eligible for fasting discontinuation according to the checklist, 249 patients (15.8%) were ordered to discontinue fasting, and 1,328 patients (84.2%) experienced unnecessary fasting. Conclusion ED patients spent significant time fasting during their ED length of stay. A high prevalence of unnecessary fasting was identified in the ED.

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.

Objective: To systematically analyze the revisions content and technological development trends of microbiological standards in the Chinese Pharmacopoeia (ChP) 2025 Edition, and explore its novel requirements in risk-based pharmaceutical product lifecycle management.
Methods: A comprehensive review was conducted on 26 microbiological-related standards to summarize the revision directions and scientific implications from perspectives including the revision overview, international harmonization of microbiological standards, risk-based quality management system, and novel tools and methods with Chinese characteristics.
Results: The ChP 2025 edition demonstrates three prominent features in microbiological-related standards: enhanced international harmonization, introduced emerging molecular biological technologies, and established a risk-based microbiological quality control system.
Conclusion: The new edition of the Pharmacopoeia has systematically constructed a microbiological standard system, which significantly improves the scientificity, standardization and applicability of the standards, providing a crucial support for advancing the microbiological quality control in pharmaceutical industries of China.

Objective To explore enteral nutrition support and analyze its influencing factors in elderly patients with ischemic stroke. Methods A total of 328 patients with ischemic stroke in General Hospital of Western Theater Command were enrolled for nutritional screening between July 2020 and February 2024. Corresponding nutritional support plans were selected to investigate the compliance of patients with enteral nutrition support. Patients were divided into a standard group (n=140) and a non-standard group (n=97) based on whether their calorie intake met the standard. The effects of different clinical characteristics on enteral nutrition support were explored, and logistic analysis was used to analyze the influencing factors of non-standard enteral nutrition support. Results In the 328 patients with ischemic stroke, proportions of total parenteral nutrition support, total enteral nutrition support, and parenteral/enteral nutrition support were 25.30%, 27.74% and 46.95%, respectively. The proportions of vomiting or regurgitation, gastric residual volume >100 mL, mechanical ventilation and use of antibiotics >2 in the non-standard group were higher than those in the standard group (P<0.05). Logistic analysis showed that the above clinical characteristics were risk factors influencing patients with enteral nutrition support and parenteral/enteral nutrition support. Conclusion Vomiting or regurgitation , gastric residual volume, mechanical ventilation, and amount of antibiotics used are important influencing factors of enteral nutrition support in patients. Clinicians should pay attention to the above clinical characteristics.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: Infliximab treatment failure in patients with inflammatory bowel disease may result from sub-optimal infliximab trough level. An understanding of pharmacokinetics (PKs) is important to maintain an optimal trough level. PK studies of the switch to subcutaneous (SC) infliximab from intravenous (IV) infliximab using real-world data are lacking. We aimed to develop a population PK model of IV and SC infliximab to predict individual infliximab exposure during maintenance therapy. Methods: We used data from prospectively collected data on IV and SC infliximab concentrations in patients with inflammatory bowel disease receiving maintenance treatment from February 2020 to December 2022 at Samsung Medical Center. Population PK analysis was conducted by using a two-compartment model with first-order absorption and first-order elimination. Goodness-of-fit plots and visual predictive check were used to evaluate the PK model. Results: A total of 2,132 samples from 181 patients (149 Crohn’s disease and 32 ulcerative colitis) were analyzed. We developed an infliximab population PK model using body mass index, albumin, C-reactive protein level, and the anti-drug antibody level and validated its predictive performance. Conclusions It may be possible to predict the infliximab trough level of both IV and SC infliximab in patients with inflammatory bowel disease during maintenance treatment by using our model in real-world practice.

Objective To investigatethe relationship between gastroesophageal reflux disease (GERD) symptoms and clinicopathological characteristics, p53 expression, and survival of Chinese patients with esophageal adenocarcinoma. Methods A total of 3882 patients with esophageal adenocarcinoma, 970 matched patients with esophageal squamous cell carcinoma, and 970 matched patients with gastric cardia adenocarcinoma were included to compare the incidence of GERD symptoms. Patients with esophageal adenocarcinoma were divided into two groups according to the presence and absence of GERD symptoms. The differences in clinicopathological characteristics and p53 expression between the two groups were compared by chi-square test, and the differences in survival between the two groups were compared by landmark analysis. Results The incidence of GERD symptoms increased successively in esophageal squamous cell carcinoma, esophageal adenocarcinoma, and gastric cardia adenocarcinoma. In patients with esophageal adenocarcinoma, the proportions of male, less than 65 years old, lower thoracic tumors, tumors without squamous cell carcinoma, poorly differentiation, early tumors (stage 0-I), and p53-positive tumors in the group with GERD symptoms were higher than those in the group without GERD symptoms; moreover, the long-term survival (≥15 years) was better. Conclusion GERD symptom is an important clinical sign of esophageal adenocarcinoma. It is closely related to specific clinicopathological characteristics, p53 overexpression, and good long-term prognosis.