Background: Despite advancements in laboratory animal facility management, pinworm infections remain a persistent issue in immunodeficient mouse colonies. Rapid diagnosis and treatment are crucial to mitigating potential scientific and economic consequences. Effective control requires both the administration of anthelmintic agents and rigorous environmental decontamination. However, the safety and efficacy of these treatments in genetically modified mouse models remains uncertain.Case presentation Aspiculuris tetraptera infestation was identified in multiple immunodeficient mouse models housed in a laboratory facility. Diagnosis was confirmed through fecal flotation for egg detection and necropsy for adult worm examination in the large intestines. Mice received three subcutaneous ivermectin injections at two-week intervals, coupled with environmental decontamination using ivermectin spray for four consecutive weeks. Following treatment, all colonies tested negative for A. tetraptera without any mortality. Conclusions A combination of subcutaneous ivermectin injection and environmental spray application effectively eradicated A. tetraptera infestation in immunodeficient mouse colonies. The treatment protocol led to the complete elimination of eggs and adult worms, offering a practical strategy for managing pinworm infections in genetically modified mouse models. Limitations include the small sample size, and the lack of a comprehensive evaluation of physiological and metabolic safety in immunodeficient mice. Further validation will be required to confirm the broader applicability of this approach.

Objective: Because of the possible therapeutic benefit of removing occult tumor cells, a source of recurrence and chemoresistance, total parietal peritonectomy (TPP) is an alternative treatment for advanced epithelial ovarian/fallopian tube/primary peritoneal cancer. Interventional studies comparing TPP with selective parietal peritonectomy (SPP) are in progress. Since surgeons skilled in TPP are essential for such trials to be conducted, this nationwide survey aimed to examine current peritonectomy practice among gynecologic oncologists in Korea. Methods: A 17-item questionnaire, developed by a surgery committee and reviewed by the scientific review board of the Korean Gynecology Oncology Group (KGOG), was distributed to 144 KGOG members. The questionnaire was divided into 3 categories: respondent demographics, peritonectomy practice during primary debulking surgery (PDS), and peritonectomy practice during interval debulking surgery (IDS). Results: We received 88 (61.1%) valid responses. Of the valid respondents, 98.9% and 93.8% performed SPP during PDS and IDS, respectively. Only 4.9% of the respondents performed TPP during IDS. Most respondents performed peritonectomy in cases where optimal postoperative outcomes were expected. Approximately 50.6% of the respondents had performed peritonectomy independently, while the others did so in cooperation with non-gynecologic surgeons. The primary reasons for not performing TPP were concerns about morbidity and uncertainty about the clinical benefits of the procedure. Conclusion SPP is the predominant technique used in both PDS and IDS in Korea. A small percentage (4.9%) of gynecologic oncologists have performed TPP during IDS. Accordingly, a study regarding the feasibility of TPP should be conducted before proceeding with a prospective clinical trial.

Patients with end-stage kidney disease (ESKD) are more susceptible to viral epidemics and are known to have higher incidence and death rates of coronavirus disease 2019 (COVID-19) compared to the general population. We determined COVID-19 incidence and mortality among chronic hemodialysis (HD), peritoneal dialysis (PD), and kidney transplantation (KT) patients in Korea. Methods: We conducted a retrospective cohort study and data regarding Korean ESKD adults (aged ≥18 years) were obtained from the National Health Insurance Service of Korea from October 2020 to December 2021. We examined and compared the incidence of COVID-19–related infections and deaths among the patients receiving HD, PD, and KT. Results: Of all ESKD patients, 85,018 (68.1%) were on HD, 8,399 (6.7%) on PD, and 31,343 (25.1%) on KT. The COVID-19 incidence was 1.3% for HD, 1.2% for PD, and 1.5% for KT. COVID-19 mortality was 16.3% for HD, 12.2% for PD, and 4.7% for KT. PD patients had a lower incidence of infection compared to HD patients (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.607–0.93), but KT patients had a significantly higher risk of infection (OR, 1.28; 95% CI, 1.13–1.44). Compared with HD, the risk of COVID-19–related death was not different for PD patients but was significantly lower for KT patients (hazard ratio, 0.55; 95% CI, 0.35–0.88). Conclusion: COVID-19 incidence was lower in PD patients than in HD patients, but mortality was not different between them. KT was associated with a higher risk of COVID-19 infection but lower mortality compared to HD.

Background: The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse. Methods: For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.1)1Enge/J mouse (allogeneic mouse, ALLO). For syngeneic control (SYN), skin grafts were transferred from C57BL/6 to C57BL/6. We performed single-cell RNA-sequencing analysis on splenocytes isolated from ALLO and SYN and compared the gene expression between them. Results: We generated 9,190 and 8,890 single-cell transcriptomes from ALLO and SYN, respectively. Five major cell types (B cells, T cells, natural killer cells, macrophages, and neutrophils) and their transcriptome data were annotated according to the representative differentially expressed genes of each cell cluster. The percentage of B cells was higher in ALLO than it was in SYN. Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the highly expressed genes in the B cells from ALLO were mainly associated with antigen processing and presentation pathways, allograft rejection, and the Th17 cell differentiation pathway. Upregulated genes in the T cells of ALLO were involved in the interleukin (IL)-17 signaling pathway. The ratio of Th17 cluster and Treg cluster was increased in the ALLO. On flow cytometry, the percentage of Th17 (IL-17+/CD4+ T) cells was higher and regulatory T cells (FOXP3+/CD4+ T) was lower in the ALLO compared to those in the SYN. Conclusion Our results indicate that not only the B cell lineage but also the Th17 cells and their cytokine (IL-17) are involved in the sensitization to HLA.

The evaluation of respiratory chemical substances has been mostly performed in animal tests (OECD TG 403, TG 412, TG 413, etc.). However, there have been ongoing discussions about the limited use of these inhalation toxicity tests due to differences in the anatomical structure of the respiratory tract, difficulty in exposure, laborious processes, and ethical reasons. Alternative animal testing methods that mimic in vivo testing are required. Therefore, in this study, we established a co-culture system composed of differentiated epithelial cells under an air-liquid interface (ALI) system in the apical part and fibroblasts in the basal part. This system was designed to mimic the wound-healing mechanism in the respiratory system. In addition, we developed a multi-analysis system that simultaneously performs toxicological and functional evaluations. Several individual assays were used sequentially in a multi-analysis model for pulmonary toxicity. Briefly, cytokine analysis, histology, and cilia motility were measured in the apical part, and cell migration and gel contraction assay were performed by exposing MRC-5 cells to the basal culture. First, human airway epithelial cells from bronchial (hAECB) were cultured under air-liquid interface (ALI) system conditions and validated pseudostratified epithelium by detecting differentiation-related epithelial markers using Transepithelial Electrical Resistance (TEER) measurement, Hematoxylin and Eosin (H&E) staining, and immunocytochemistry (ICC) staining. Afterward, the co-culture cells exposed to Transforming growth factor-beta 1 (TGF-β1), a key mediator of pulmonary fibrosis, induced significant toxicological responses such as cytotoxicity, cell migration, and gel contraction, which are wound-healing markers. In addition, cilia motility in epithelial cells was significantly decreased compared to control. Therefore, the multi-analysis model with a 3D epithelial-fibroblast co-culture system is expected to be useful in predicting pulmonary toxicity as a simple and efficient high-throughput screening method and as an alternative to animal testing.

Purpose: To identify the prevalence and risk factors of coronavirus disease 2019 (COVID-19) reinfection in patients with rheumatoid arthritis (RA). Materials and Methods: This study retrospectively analyzed patients with RA with a documented COVID-19 infection between January 2021 and December 2022 at a tertiary hospital in Seoul, South Korea. Reinfection was defined as a subsequent positive test result for severe acute respiratory syndrome coronavirus 2 at least 3 months after the initial infection. Cox proportional hazards models with backward elimination were employed to assess the association between potential risk factors and risk of reinfection. Results: Of 351 included patients with RA {female, 81.5%; median age, 58.0 years [interquartile range (IQR), 48.0–66.0]}, 252 (71.8%) were treated with methotrexate and 12 (3.4%) received leflunomide during the initial infection. Over a median follow-up of 1.5 (IQR, 1.1–1.6) years, 43 (12.3%) patients experienced reinfection, equating to an incidence rate of 8.97 per 100 patient-years.The median time interval between infections was 0.8 (IQR, 0.6–1.2) years. Among the risk factors, leflunomide use showed a significant association with reinfection (hazard ratio, 2.968; 95% confidence interval, 1.057–8.335; p=0.039). However, no significant changes occurred in disease activity following reinfection [disease activity score using 28 joints: baseline median, 2.3 (IQR, 1.9– 2.8); post-reinfection median, 2.3 (IQR, 1.8–2.6), p for change=0.895]. Conclusion In this retrospective cohort study of patients with RA with COVID-19 infection, approximately 12% of patients experienced reinfection without significant change in disease activity. Leflunomide use was associated with a higher risk of reinfection.

Background/Aims: Quick sequential organ failure assessment (qSOFA) is believed to identify patients at risk of poor outcomes in those with suspected infection. We aimed to evaluate the ability of modified qSOFA (m-qSOFA) to identify high-risk patients among those with acutely deteriorated chronic liver disease (CLD), especially those with acute-onchronic liver failure (ACLF). Methods: We used data from both the Korean Acute-on-Chronic Liver Failure (KACLiF) and the Asian Pacific Association for the Study of the Liver ACLF Research Consortium (AARC) cohorts. qSOFA was modified by replacing the Glasgow Coma Scale with hepatic encephalopathy, and an m-qSOFA ≥2 was considered high. Results: Patients with high m-qSOFA had a significantly lower 1-month transplant-free survival (TFS) in both cohorts and higher organ failure development in KACLiF than those with low m-qSOFA (Ps<0.05). Subgroup analysis by ACLF showed that patients with high m-qSOFA had lower TFS than those with low m-qSOFA. m-qSOFA was an independent prognostic factor (hazard ratios, HR=2.604, 95% confidence interval, CI 1.353–5.013, P=0.004 in KACLiF and HR=1.904, 95% CI 1.484– 2.442, P<0.001 in AARC). The patients with low m-qSOFA at baseline but high m-qSOFA on day 7 had a significantly lower 1-month TFS than those with high m-qSOFA at baseline but low m-qSOFA on day 7 (52.6% vs. 89.4%, P<0.001 in KACLiF and 26.9% vs. 61.5%, P<0.001 in AARC). Conclusions Baseline and dynamic changes in m-qSOFA may identify patients with a high risk of developing organ failure and short-term mortality among CLD patients with acute deterioration.

Background/Aims: Although guidelines exist regarding the evaluation and management of patients with chronic constipation (CC), little is known about real-world clinical practice patterns. This study aimed to evaluate the various practices used to manage CC patients in various clinical settings in South Korea. Methods: A nationwide web-based survey was conducted, randomly selecting gastroenterologists and non-gastroenterologists. The 25-item questionnaire included physicians’ perceptions and practices regarding the available options for diagnosing and managing CC patients in Korea. Results: The study participants comprised 193 physicians (86 gastroenterologists, 44.6%) involved in the clinical management of CC patients. The mean clinical experience was 12 years. Only 21 of 193 respondents (10.9%) used the Rome criteria when diagnosing CC. The Bristol Stool Form Scale was used by 29% of the respondents (56/193), while the digital rectal examination was performed by 11.9% of the respondents (23/193). Laboratory testing and colonoscopies were performed more frequently by gastroenterologists than by non-gastroenterologists (both p=0.001). Physiologic testing was used more frequently by gastroenterologists (p=0.046), phy-sicians at teaching hospitals, and physicians with clinical experience ≤10 years (both p<0.05). There were also significant differences in the preference for laxatives depending on the type of hospital. Conclusions There were discrepancies in the diagnosis and management of CC patients depending on the clinical setting. The utilization rates of the Bristol Stool Form Scale and digital rectal examination by physicians are low in real-world clinical practice. These results imply the need for better and more practical training of physicians in the assessment and management of CC.

Background/Aims: We investigated how interactions between humans and computer-aided detection (CADe) systems are influenced by the user’s experience and polyp characteristics. Methods: We developed a CADe system using YOLOv4, trained on 16,996 polyp images from 1,914 patients and 1,800 synthesized sessile serrated lesion (SSL) images. The performance of polyp detection with CADe assistance was evaluated using a computerized test module. Eighteen participants were grouped by colonoscopy experience (nurses, fellows, and experts). The value added by CADe based on the histopathology and detection difficulty of polyps were analyzed. Results: The area under the curve for CADe was 0.87 (95% confidence interval [CI], 0.83 to 0.91). CADe assistance increased overall polyp detection accuracy from 69.7% to 77.7% (odds ratio [OR], 1.88; 95% CI, 1.69 to 2.09). However, accuracy decreased when CADe inaccurately detected a polyp (OR, 0.72; 95% CI, 0.58 to 0.87). The impact of CADe assistance was most and least prominent in the nurses (OR, 1.97; 95% CI, 1.71 to 2.27) and the experts (OR, 1.42; 95% CI, 1.15 to 1.74), respectively. Participants demonstrated better sensitivity with CADe assistance, achieving 81.7% for adenomas and 92.4% for easy-to-detect polyps, surpassing the standalone CADe performance of 79.7% and 89.8%, respectively. For SSLs and difficult-to-detect polyps, participants' sensitivities with CADe assistance (66.5% and 71.5%, respectively) were below those of standalone CADe (81.1% and 74.4%). Compared to the other two groups (56.1% and 61.7%), the expert group showed sensitivity closest to that of standalone CADe in detecting SSLs (79.7% vs 81.1%, respectively). Conclusions CADe assistance boosts polyp detection significantly, but its effectiveness depends on the user’s experience, particularly for challenging lesions.

Purpose: To identify the prevalence and risk factors of coronavirus disease 2019 (COVID-19) reinfection in patients with rheumatoid arthritis (RA). Materials and Methods: This study retrospectively analyzed patients with RA with a documented COVID-19 infection between January 2021 and December 2022 at a tertiary hospital in Seoul, South Korea. Reinfection was defined as a subsequent positive test result for severe acute respiratory syndrome coronavirus 2 at least 3 months after the initial infection. Cox proportional hazards models with backward elimination were employed to assess the association between potential risk factors and risk of reinfection. Results: Of 351 included patients with RA {female, 81.5%; median age, 58.0 years [interquartile range (IQR), 48.0–66.0]}, 252 (71.8%) were treated with methotrexate and 12 (3.4%) received leflunomide during the initial infection. Over a median follow-up of 1.5 (IQR, 1.1–1.6) years, 43 (12.3%) patients experienced reinfection, equating to an incidence rate of 8.97 per 100 patient-years.The median time interval between infections was 0.8 (IQR, 0.6–1.2) years. Among the risk factors, leflunomide use showed a significant association with reinfection (hazard ratio, 2.968; 95% confidence interval, 1.057–8.335; p=0.039). However, no significant changes occurred in disease activity following reinfection [disease activity score using 28 joints: baseline median, 2.3 (IQR, 1.9– 2.8); post-reinfection median, 2.3 (IQR, 1.8–2.6), p for change=0.895]. Conclusion In this retrospective cohort study of patients with RA with COVID-19 infection, approximately 12% of patients experienced reinfection without significant change in disease activity. Leflunomide use was associated with a higher risk of reinfection.