Spinner dolphins (Stenella longirostris subsp.) occupy the nearshore waters of several Hawaiian Islands. Due to their constrained behavioral pattern and genetic isolation, they are vulnerable to anthropogenic threats.
View Article and Find Full Text PDFNanotopographic materials provide special biophysical stimuli that can regulate epithelial tight junctions and their barrier function. Through the use of total internal reflection fluorescence microscopy of live cells, we demonstrated that contact of synthetic surfaces with defined nanotopography at the apical surface of epithelial monolayers increased paracellular permeability of macromolecules. To monitor changes in tight junction morphology in live cells, we fluorescently tagged the scaffold protein zonula occludens-1 (ZO-1) through CRISPR/Cas9-based gene editing to enable live cell tracking of ZO-1 expressed at physiologic levels.
View Article and Find Full Text PDFPurpose: To develop a planar, asymmetric, micro-scale oral drug delivery vehicle by i) fabricating microdevice bodies with enteric materials, ii) efficiently and stably loading sensitive drug molecules, and iii) capping microdevices for controlled drug release.
Methods: Picoliter-volume inkjet printing was used to fabricate microdevices through additive manufacturing via drop-by-drop deposition of enteric polymer materials. Microdevice bodies with reservoirs are fabricated through deposition of an enteric polymer, Eudragit FS 30 D.
Oral delivery of therapeutics is the preferred route for systemic drug administration due to ease of access and improved patient compliance. However, many therapeutics suffer from low oral bioavailability due to low pH and enzymatic conditions, poor cellular permeability, and low residence time. Microfabrication techniques have been used to create planar, asymmetric microdevices for oral drug delivery to address these limitations.
View Article and Find Full Text PDFUnderstanding the phenotypic development of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) is a prerequisite to advancing regenerative cardiac therapy, disease modeling, and drug screening applications. Lack of consistent hiPSC-CM in vitro data can be largely attributed to the inability of conventional culture methods to mimic the structural, biochemical, and mechanical aspects of the myocardial niche accurately. Here, we present a nanogrid culture array comprised of nanogrooved topographies, with groove widths ranging from 350 to 2000 nm, to study the effect of different nanoscale structures on the structural development of hiPSC-CMs in vitro.
View Article and Find Full Text PDFThe oral route of drug administration is most preferred due to its ease of use, low cost, and high patient compliance. However, the oral uptake of many small molecule drugs and biotherapeutics is limited by various physiological barriers, and, as a result, drugs suffer from issues with low solubility, low permeability, and degradation following oral administration. The flexibility of micro- and nanofabrication techniques has been used to create drug delivery platforms designed to address these barriers to oral drug uptake.
View Article and Find Full Text PDFWe have examined the effects of surface nanotopography and hyaluronic acid (HA) on in vitro chondrogenesis of dental pulp stem cells (DPSCs). Ultraviolet-assisted capillary force lithography was employed to fabricate well-defined nanostructured scaffolds of composite PEG-GelMA-HA hydrogels that consist of poly(ethylene glycol) dimethacrylate (PEGDMA), methacrylated gelatin (GelMA), and HA. Using this microengineered platform, we first demonstrated that DPSCs formed three-dimensional spheroids, which provide an appropriate environment for in vitro chondrogenic differentiation.
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