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Than, N.

Publications and source records attributed to Than, N..

3 recordsLinked to original sources

Advanced Fabrication Protocol of an Elastic Porous Membrane for Organ-on-a-chip Applications

Elastic porous membranes are essential components of mechanically active organ-on-a-chip and microphysiological system (MPS) platforms, where cyclic strain is required to recapitulate physiologically relevant tissue mechanics. However, existing fabrication methods are often difficult to reproduce, low throughput, or dependent on specialized infrastructure, limiting their adoption across laboratories. Many protocols also lack quality control steps for ensuring device assembling and reproducibility. In this paper, we present a robust and accessible fabrication and quality control workflow for the consistent production of elastic porous PDMS membranes. The method uses commercially available heat presses, release liners, and pre-patterned membrane wafers to enable rapid membrane molding. We describe a quality control framework, including visual verification of porous regions and wettability testing for surface activation, to ensure irreversible PDMS bonding and reliable device assembly. Together, this workflow improves fabrication yield, reduces device failure, and supports reproducible implementation of elastic porous membrane in organ-on-a-chip applications.

bioengineering↗

Probiotic Intervention Mitigates Radiation-Induced Intestinal Injury by Alleviating Oxidative Stress in a Human Gut-on-a-chip

Gastrointestinal acute radiation syndrome (GI-ARS) poses a critical public health concern, necessitating the development of effective medical countermeasures (MCM). Here, we evaluated the therapeutic potential of a commercially available probiotic formulation using human gut-on-a-chip model that mimics physiodynamic intestinal microenvironment. Intestinal epithelial Caco-2 cells were subjected to 8 Gray gamma radiation, targeting the epithelial layer, the culture medium, or both. The irradiated epithelial cells challenged to the irradiated medium resulted in significant DNA damage quantified by the presence of 53BP1 foci, increased cellular injury, and disrupted epithelial morphology. While epithelial irradiation alone did not compromise structural integrity, longitudinal exposure to irradiated medium induced oxidative stress, leading to morphological damage. Administration of the probiotic formulation significantly suppressed reactive oxygen species production, reduced epithelial damage, and preserved microarchitecture, independent of direct modulation of DNA damage. These findings suggest that probiotics may serve as promising live biotherapeutic MCM for mitigating GI-ARS in high-risk radiological exposures.

bioengineering↗

Mechanostimulatory cues determine intestinal fibroblast fate and profibrotic remodeling in a physiodynamic human gut-on-a-chip

Biomechanical cues, including shear stress and mechanical strain, are key regulators of intestinal cellular behavior, yet their mechanostimulatory impact on fibroblasts responses during early fibrotic remodeling remains poorly understood. Using a bioengineered gut-on-a-chip model, we independently modulated flow and mechanical strain to assess fibroblast dynamics under intact or impaired epithelial barriers. Inflammation-associated fibroblasts resisted biomechanical stress, exhibiting myofibroblast-like phenotypes with hypertrophy and elevated -smooth muscle actin aligned with stress fibers. In contrast, normal fibroblasts were highly susceptible to shear stress, undergoing matrix metalloproteinase-dependent apoptotic injury, while mechanical strain alone had minimal effect. Notably, an intact epithelial barrier was both necessary and sufficient to protect fibroblasts from shear-induced damage, suggesting that "good fences make good neighbors". Under barrier dysfunction, prolonged exposure to shear stress induced the formation of stiff fibroblast aggregates composed of mechanoadaptive myofibroblast-like cells. These findings identify mechanostimulatory cues, particularly shear stress, as critical drivers of early fibrotic remodeling in inflammatory bowel disease and underscore epithelial barrier integrity as an essential biomechanical safeguard against pathological fibroblast dysregulation.

bioengineering↗