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Khlaifat, B.

Publications and source records attributed to Khlaifat, B..

2 recordsLinked to original sources

Pulsed electrical stimulation enhances intestinal permeability

Oral ingestion of drugs remains the most convenient method for pharmacotherapy. However, oral absorption is hampered by digestive enzymes and the intestinal epithelial barrier. Here we investigate the ability of electrical stimuli to biologically modulate intestinal permeability. We demonstrate that pulsed electrical stimulation increases intestinal permeability, facilitating transport of chemical species across the epithelium. We evaluate the effects of several stimulation parameters in silico and subsequently characterize the biological effects in vitro using Caco-2 colorectal cancer cells, and an acute in vivo intestinal model. Our findings suggest that these effects may be mediated through calcium-dependent interactions with tight junction proteins which induce a reversible permeability increase differing based on the total charge delivered, amplitude and frequency of the current delivered. Pulsed electrical stimulation could be a potential strategy for transiently modulating the intestinal barrier.

bioengineering↗

3D Printed Customizable Radiopaque Markers for Assessing Gastrointestinal Transit

Tracking gastrointestinal (GI) transit in preclinical models is essential for assessing gut motility and drug delivery. Current preclinical methods rely on end-to-end transit measurements or emptying studies that require terminal endpoints and organ explanation. Clinically, radiopaque "Sitz" markers are administered orally and their position in the GI tract is assessed through radiography. Sitz markers have been in use since 1969 and are typically mass-produced using industrial molding or extrusion, resulting in a single, fixed geometry with limited tunability. We present a stereolithography (SLA)-based method to fabricate customizable radiopaque markers using additive manufacturing with a barium sulfate (BaSO4)-doped resin. We demonstrate precise control over marker geometry, a key advantage over existing markers. Furthermore, we apply this method in vivo, tracking markers in a live rat model from ingestion to excretion using serial CT imaging. We systematically investigate how changes in marker geometry impact GI residency and transit time. Our results show that 3D printed markers provide a flexible and tunable platform for radiopaque marker fabrication and enable investigation of the fundamental relationship between a markers physical properties and its performance in a dynamic biological environment. This work establishes a novel, tunable platform for GI motility evaluation and drug delivery studies.

bioengineering↗