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Experimental evidence has demonstrated the ability of transient pulses of electric fields to alter mammalian cell behavior. Strategies with these pulsed electric fields (PEFs) have been developed for clinical applications in cancer therapeutics, in-vivo decellularization, and tissue regeneration. Successful implementation of these strategies involve understanding how PEFs impact the cellular structures and, hence, cell behavior. The caveat, however, is that the PEF parameter space (i.e., comprising different pulse widths, amplitudes, number of pulses) is large, and design of experiments to explore all possible combinations of pulse parameters is prohibitive from a cost and time standpoint. In this study, a scaling law based on the Ising model is introduced to understand the impact of PEFs on the outer cell lipid membrane so that an understanding developed in one PEF pulse regime may be extended to another. Combining non-Markovian Monte Carlo techniques to determine density-of-states with a novel non-equilibrium thermodynamic framework based on the principle of steepest entropy ascent, the applicability of this scaling model to predict the behavior of both thermally quenched and electrically perturbed lipid membranes is demonstrated. A comparison of the predictions made by the steepest-entropy-ascent quantum thermodynamic (SEAQT) framework to experimental data is performed to validate the robustness of this computational methodology and the resulting scaling law 

Abstract Problem-based learning (PBL) has been effectively used within BME education, though there are several challenges in its implementation within courses with larger enrollments. Furthermore, the sudden transition to online learning from the COVID-19 pandemic introduced additional challenges in creating a similar PBL experience in an online environment. Online constrained PBL was implemented through asynchronous modules and synchronous web conferencing with rotating facilitators. Overall, facilitators perceived web conferencing facilitation to be similar to in-person, but noted that students were more easily “hidden” or distracted. Students did not comment on web conferencing facilitation specifically, but indicated the transition to online PBL was smooth. Course instructors identified that a fully synchronous delivery as well as modifications of Group Meeting Minutes assignments as potential modifications for future offerings. Future work will aim to address the perceptions and effectiveness of web conferencing facilitation for PBL courses within an undergraduate BME curriculum, as web conferencing could prove to be another significant breakthrough in addressing challenges of problem-based learning courses. 

Glioblastoma (GBM), characterized by high infiltrative capacity, is the most common and deadly type of primary brain tumor in adults. GBM cells, including therapy‐resistant glioblastoma stem‐like cells (GSCs), invade the healthy brain parenchyma to form secondary tumors even after patients undergo surgical resection and chemoradiotherapy. New techniques are therefore urgently needed to eradicate these residual tumor cells. A thiol‐Michael addition injectable hydrogel for compatibility with GBM therapy is previously characterized and optimized. This study aims to develop the hydrogel further to capture GBM/GSCs through CXCL12‐mediated chemotaxis. The release kinetics of hydrogel payloads are investigated, migration and invasion assays in response to chemoattractants are performed, and the GBM‐hydrogel interactions in vitro are studied. With a novel dual‐layer hydrogel platform, it is demonstrated that CXCL12 released from the synthetic hydrogel can induce the migration of U251 GBM cells and GSCs from the extracellular matrix microenvironment and promote invasion into the synthetic hydrogel via amoeboid migration. The survival of GBM cells entrapped deep into the synthetic hydrogel is limited, while live cells near the surface reinforce the hydrogel through fibronectin deposition. This synthetic hydrogel, therefore, demonstrates a promising method to attract and capture migratory GBM cells and GSCs responsive to CXCL12 chemotaxis.

 

Electroresponsive hydrogels possess a conducting material component and respond to electric stimulation through reversible absorption and expulsion of water. The high level of hydration, soft elastomeric compliance, biocompatibility, and enhanced electrochemical properties render these hydrogels suitable for implantation in the brain to enhance the transmission of neural electric signals and ion transport. This review provides an overview of critical electroresponsive hydrogel properties for augmenting electric stimulation in the brain. A background on electric stimulation in the brain through electroresponsive hydrogels is provided. Common conducting materials and general techniques to integrate them into hydrogels are briefly discussed. This review focuses on and summarizes advances in electric stimulation of electroconductive hydrogels for therapeutic applications in the brain, such as for controlling delivery of drugs, directing neural stem cell differentiation and neurogenesis, improving neural biosensor capabilities, and enhancing neural electrode‐tissue interfaces. The key challenges in each of these applications are discussed and recommendations for future research are also provided.