Transcriptomic analysis of a 3D blood-brain barrier model exposed to disturbed fluid flow.

Cerebral aneurysms are more likely to form at bifurcations in the vasculature, where disturbed fluid is prevalent due to flow separation at sufficiently high Reynolds numbers. While previous studies have demonstrated that altered shear stress exerted by disturbed flow disrupts endothelial tight junctions, less is known about how these flow regimes alter gene expression in endothelial cells lining the blood-brain barrier. Specifically, the effect of disturbed flow on expression of genes associated with cell-cell and cell-matrix interaction, which likely mediate aneurysm formation, remains unclear.

Implementation and characterization of a physiologically relevant flow waveform in a 3D microfluidic model of the blood-brain barrier.

Previous in vitro studies interrogating the endothelial response to physiologically relevant flow regimes require specialized pumps to deliver time-dependent waveforms that imitate in vivo blood flow. The aim of this study is to create a low-cost and broadly adaptable approach to mimic physiological flow, and then use this system to characterize the effect of flow separation on velocity and shear stress profiles in a three-dimensional (3D) topology. The flow apparatus incorporates a programmable linear actuator that superposes oscillations on a constant mean flow driven by a peristaltic pump to emulate flow in the carotid artery.

Disturbed flow disrupts the blood-brain barrier in a 3D bifurcation model.

The effect of disturbed flow profiles on the endothelium have been studied extensively in systemic vasculature, but less is known about the response of the blood-brain barrier (BBB) to these flow regimes. Here we investigate the effect of disturbed flow on the integrity of the BBB using a three-dimensional, perfusable bifurcation model consisting of a co-culture of endothelial cells with mural and glial cells. Experimental flow patterns predicted by computational fluid dynamics mimic in vivo flow regimes, specifically the presence of a recirculation zone immediately downstream of the bifurcation.

Hyaluronan Disrupts Cardiomyocyte Organization within 3D Fibrin-Based Hydrogels.

The extracellular matrix in vivo contains variable but often large amounts of glycosaminoglycans that influence cell and tissue function. Hyaluronan (HA) is an abundant glycosaminoglycan within the extracellular matrix of the myocardium during early development and in the aftermath of a myocardial infarction. Its flexible anionic structure has a strong influence on mechanical response and interstitial fluid flow within the matrix.

Impact of Design Changes in Gastrostomy Tube (G-tube) Devices for Patients Who Rely on Home-Based Blenderized Diets for Enteral Nutrition.

Objective: Blenderized diets are gaining increasing popularity among enteral tube users. Connectors in gastrostomy tubes (G-tubes) are undergoing standardization to reduce misconnections. These standardized G-tubes are referred to as ENFit G-tubes.