https://scholar.dgist.ac.kr/handle/20.500.11750/10164 2026-07-26T10:50:56Z https://scholar.dgist.ac.kr/handle/20.500.11750/60470 Title: Bioreducible Cu2O cluster-glutathione nanohybrids with multienzyme-mimetic ROS scavenging for cisplatin-induced acute kidney injury Author(s): Lee, Hokyung; Noh, Dahye; Lee, Kyeong-Min; Ahn, Young; Park, Shin Young; Shin, Jiyeon; Shim, Man Kyu; Kim, Sun Hwa; Noh, Tae Il; Kim, Hyun-Chul; Lee, Sangmin; Kim, Kwangmeyung; Han, Hwa Seung; Yoon, Hong Yeol Abstract: Cisplatin (Cis)-induced nephrotoxicity remains a major clinical challenge, largely driven by reactive oxygen species (ROS)-mediated oxidative stress leading to acute kidney injury (AKI). Because effective therapies for AKI remain limited, antioxidants capable of scavenging ROS and selectively accumulating in injured kidney tissue are highly desirable. Artificial nanocatalysts have emerged as promising antioxidant therapeutics owing to their advantages over natural enzymes. Here, we developed bioreducible nanohybrids (GCuNPs) composed of copper(I) oxide (Cu2O) nanocatalysts stabilized by glutathione (GSH), synthesized via the reductive reaction of copper ions in the presence of ascorbic acid and GSH. GCuNPs exhibited enhanced broad-spectrum ROS-scavenging capacity and multi-enzyme-like activities in vitro . Following systemic administration in a Cis-induced AKI mouse model, GCuNPs preferentially accumulated in injured kidneys through an impaired glomerular filtration barrier and loosening of proximal tubular tight junctions. Immunofluorescence analysis revealed that GCuNPs significantly reduced the expression of KIM-1, a proximal tubular injury marker, while preserving HO-1 expression, indicating attenuation of tubular damage and preservation of endogenous antioxidant defense. Furthermore, GCuNP treatment significantly reduced serum creatinine and blood urea nitrogen levels, improved survival, and showed no noticeable toxicity. These findings highlight GCuNPs as a promising therapeutic strategy for mitigating Cis-induced nephrotoxicity and potentially other oxidative stress-associated kidney disorders. 2026-05-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60365 Title: Automating population construction and parallel simulation of biophysical models for neuromuscular cells: An inverse approach Author(s): Kim, Hojeong Abstract: Biophysical modeling and simulation help to promote a comprehensive understanding of the neuromuscular mechanisms underlying muscle force generation and control in normal and pathological states. However, this process is labor intensive and limited to special conditions due to the heterogeneity of neuromuscular cells and the variability in their organization across body parts and ages. We present a methodology to resolve this issue. First, we formulate a building-block approach with an inverse modeling framework for automated population construction and tractable hierarchical analysis under various physiological conditions. Second, we devise a network folder-based approach with a virtual environment technique for efficient parallel simulation that can operate on a multicore computer, a supercomputing system, or a computer network through the internet. Third, we implement the methodology by developing open-source command-line software called pNMS. Finally, we demonstrate that pNMS can replicate experimental and simulation results from different environments and predict the population behaviors of neuromuscular cells depending on their organization and muscle length. With an intuitive, flexible application programming interface, this software tool may offer a solution for promoting efficient investigation and an in-depth understanding of neuromuscular function at cellular resolution under realistic scenarios. 2026-03-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59954 Title: Metixene hydrochloride hydrate mitigates kidney tubulointerstitial fibrosis by inhibiting Smad3 phosphorylation Author(s): Lee, Kyeong-Min; Hwang, Yeo Jin Abstract: Chronic Kidney disease (CKD), in which renal fibrosis is the defining pathological feature, poses significant global health and economic challenges. Despite its high clinical prevalence, effective therapies to prevent or reverse renal fibrosis remain scarce. Metixene hydrochloride hydrate (MHH), an anticholinergic drug once used for Parkinson's disease, has not been evaluated for renal fibrosis. Here, we investigated whether MHH mitigates renal fibrosis in a unilateral ureteral obstruction (UUO) mouse model and evaluated its effects on transforming growth factor-β1 (TGF-β1) signaling in renal cells. MHH did not affect the cell viability of NRK-49F cells at concentrations ranging from 0.5 to 5 μM. In vitro, MHH effectively suppressed TGF-β1-induced PAI-1 expression (both mRNA and protein) and secretion in renal fibroblasts, as well as PAI-1 secretion and protein expression in renal glomerular endothelial cells. Furthermore, TGF-β1 stimulated the mRNA and protein expressions of key renal fibrotic factors, including collagen type I, fibronectin, and alpha-smooth muscle actin, in NRK-49F cells. MMH significantly inhibited the expression of these renal fibrotic factors in these cells. UUO kidneys exhibited markedly increased tubular atrophy and interstitial fibrosis, as well as increased expression of renal fibrotic markers. MHH treatment significantly mitigated these pathological parameters and expression of renal fibrotic markers. Mechanistically, MHH suppressed TGF-β1-induced Smad3 phosphorylation both in vitro and in vivo. Our findings indicate that MHH exerts potent antifibrotic effects by downregulating the TGF-β1/Smad3 signaling pathway and suppressing the expression of fibrotic factors in renal cells and obstructed kidneys. Therefore, MHH could be repositioned as a therapeutic agent for renal fibrosis in various kidney diseases. 2026-02-28T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59401 Title: Synthesis of Block Copolymers Through Melt Polymerization for Compatibilizing PLA/PBAT Blends Author(s): Kwon, Mi Kyung; Lee, Young Jae; Lee, Se Geun; Kim, Sang Gu; Lee, Sung Jun Abstract: Block copolymers, unlike reactive compatibilizers, can stably localize at the interface without reducing biodegradation rate, making them attractive compatibilizers for PLA/PBAT blends. For industrial use, they should be synthesized from commercial PBAT by melt polymerization to lower costs. However, melt polymerization is exposed to ambient moisture, leading to concurrent formation of PLA homopolymer. In this study, PLA-PBAT block copolymers were synthesized by both solution and melt polymerization with different lactide feed ratios. Melt polymerization was performed in an internal mixer as a precursor to reactive extrusion. Products were characterized by NMR, FT-IR, GPC, DSC, and TGA, and performance in blends was evaluated using DSC, SEM, and UTM. Melt samples displayed two cold crystallization peaks. The high-temperature peak corresponded to PLA homopolymer and became more pronounced with increasing lactide feed ratio. This suggests that excess lactide was consumed in homopolymerization. The presence of PLA homopolymer was more clearly observed in DTA than in GPC. In blends, melt samples improved tensile strength gradually with increasing lactide ratio, whereas solution samples showed the highest strength at a 1:1 PBAT-to-lactide ratio. At the ratio, the blend with solution samples exhibited higher tensile strength than that with melt samples. However, this difference was mitigated when melt samples with higher lactide ratios were incorporated at contents of 5 phr or less. The pristine blend formed metastable alpha ' crystals, while melt-sample-containing blends exhibited both alpha and alpha ' structures, with the alpha form becoming more dominant at higher lactide ratios. 2025-11-30T15:00:00Z