https://scholarworks.korea.ac.kr/kumedicine/handle/2020.sw.kumedicine/510 2026-04-09T12:39:40Z https://scholarworks.korea.ac.kr/kumedicine/handle/2021.sw.kumedicine/78689 Title: Identification of microRNA-Related Target Genes for the Development of Otic Organoids Authors: Lee, Sehee; Park, Sungjin; Park, Euyhyun; Im, Gi Jung; Chang, Jiwon Abstract: Mammalian hearing loss is typically permanent due to the inability to replace damaged cochlear hair cells. However, the neonatal mice inner ear demonstrates regenerative capacity, with cochlear floor cells proliferating and differentiating into organoids containing new hair cells and supporting cells, yet the governing molecular mechanisms remain poorly understood. Here, we isolated extracellular vesicles (EVs) from inner ear organoids at proliferation and differentiation stages, characterized their EV miRNA profiles through sequencing, and validated findings using public transcriptomic datasets to elucidate miRNA-mediated regulatory mechanisms during inner ear development. Inner ear organoids were successfully developed from cochlear duct cells, expressing otic progenitor marker SOX2 and hair cell marker Myo7A and demonstrating functional mechano-transduction activity through FM1-43 uptake. Small RNA sequencing identified 35 differentially expressed EV miRNAs between developmental stages. Integrated analysis with public transcriptome datasets revealed 18 genes with significant differential expression, leading to identification of three key regulatory genes-Trp53, Ezh2, and Zbtb4-that exhibited dynamic spatiotemporal expression during inner ear maturation. Pathway analysis demonstrated that these genes are associated with DNA Repair, P53, and Wnt/beta-Catenin signaling with remarkable cell-type specificity. Our results demonstrate that EV miRNAs are temporally regulated during organoid development, with predominant downregulation during differentiation. These findings provide crucial insights into developmental mechanisms that could optimize organoid-based models and guide EV miRNA-based therapeutic strategies for hearing restoration. 2025-10-01T00:00:00Z https://scholarworks.korea.ac.kr/kumedicine/handle/2021.sw.kumedicine/78455 Title: Novel Polycaprolactone Based Coating for Catheters: Sustained Antibiotic Release for Enhanced Infection Prevention Authors: Kim, Kyungmi; Kim, Eung Hwi; Yoon, Seung Zhoo; Lee, Suk Joong Abstract: Healthcare-associated infections are a serious concern, particularly in patients with intravascular catheters. In this study, we developed a novel ampicillin-loaded polycaprolactone (PCL)-coated polyurethane catheter (PUC) wherein polymethylhydrosiloxane (PMHS) enhanced the adhesion between PCL and PUC, ensuring coating durability. PUC were first treated with PMHS, followed by PCL coatings containing 1, 3, or 6 wt% ampicillin. Antibacterial activity against Listeria innocua and Escherichia coli was evaluated using the plate counting method over 40 d. Scanning electron microscopy confirmed that the coating was uniform and stable for over 40 d. Furthermore, antibacterial efficacy was maintained for 10, 30, and 40 d for the 1, 3, and 6 wt% ampicillin coatings, respectively. Compared to the uncoated controls, the bacterial counts were reduced by over 99.9%. Thus, PMHS pretreatment of a catheter coated with ampicillin-loaded PCL exhibited sustained antibacterial activity. Our findings show PMHS enhances the coating adhesion and ensures gradual uniform degradation of the PCL layer. 2025-09-01T00:00:00Z https://scholarworks.korea.ac.kr/kumedicine/handle/2021.sw.kumedicine/77105 Title: A Comparative Study of Convolutional Neural Network and Recurrent Neural Network Models for the Analysis of Cardiac Arrest Rhythms During Cardiopulmonary Resuscitation Authors: Lee, Sijin; Lee, Kwang-Sig; Park, Hyun-Joon; Han, Kap Su; Song, Juhyun; Lee, Sung Woo; Kim, Su Jin Abstract: To develop and evaluate deep learning models for cardiac arrest rhythm classification during cardiopulmonary resuscitation (CPR), we analyzed 508 electrocardiogram (ECG) segments (each 4 s in duration, recorded at 250 Hz) from 131 cardiac arrest patients. Compression-affected segments were recorded during chest compressions, while non-compression segments were extracted during compression pauses or immediately after return of spontaneous circulation (ROSC) declaration. One-dimensional convolutional neural network (1D-CNN) and recurrent neural network (RNN) models were employed for four binary classification tasks: (1) shockable rhythms (VF and pVT) versus non-shockable rhythms (asystole and PEA) in all ECG segments; (2) the same classification in compression-affected ECG segments; (3) pulse-generating rhythms (ROSC rhythm) versus non-pulse-generating rhythms (asystole, PEA, VF and pVT) in all ECG segments; and (4) the same classification in compression-affected ECG segments. The 1D-CNN model consistently outperformed the RNN model across all classification tasks. For shockable versus non-shockable rhythm classification, the 1D-CNN achieved accuracies of 91.3% and 89.8% for all ECG segments and compression-affected ECG segments, respectively, compared to 50.6% and 54.5% for the RNN. In detecting pulse-generating rhythms, the 1D-CNN demonstrated accuracies of 90.9% and 85.7% for all ECG segments and compression-affected ECG segments, respectively, while the RNN achieved 92.2% and 84.4%. The 1D-CNN model demonstrated superior performance in cardiac arrest rhythm classification, maintaining high accuracy even with compression-affected ECG data. 2025-04-01T00:00:00Z https://scholarworks.korea.ac.kr/kumedicine/handle/2021.sw.kumedicine/67037 Title: Effects of intravenous inflammasome inhibitor (NuSepin) on suppression of proinflammatory cytokines release induced by cardiopulmonary bypass in swine model: a pilot study Authors: Yoon, Seung Zhoo; Park, Jeong Jun; Jung, Jae Seung; Kim, Ji Eon; Lee, Seung Hyong; Lee, Jeonghoon; Kim, Eung Hwi Abstract: The systemic inflammatory response syndrome can occur due to an inflammatory reaction to the release of cytokines, and it has been linked to the circulation of pro- and anti-inflammatory cytokines. The cardiopulmonary bypass (CPB) system is known to activate numerous inflammatory pathways. Applying CPB in large animals for an extended period may be useful as a controlled experimental model for systemic inflammatory responses. The authors hypothesized that 0.2 mg/kg NuSepin® would inhibit CBP-induced proinflammatory cytokine release, and attenuate CPB-induced vasoplegia. CPB was maintained for 2 h in 8 male Yorkshire pigs. Ten ml of saline was administered intravenously to the control group, while the study group received 10 ml of NuSepin® (0.2 mg/kg), before start of CPB. Blood samples were collected at four different time points to evaluating the level of cytokine (TNF-α, IL-1β, IL-6, IL-8) release during and after CBP. All vital signals were recorded as continuous waveforms using the vital recorder®. Our study demonstrated that IL-6 increased in both groups during CPB remained unchanged. However, in the Nusepin group, IL-6 levels rapidly decreased when CPB was stopped and the proinflammatory reaction subsided. Furthermore, the dose of norepinephrine required to maintain a mean pressure of 60 mmHg was also lower in the Nusepin group. © The Author(s) 2024. 2024-06-01T00:00:00Z