ATP-binding cassette (ABC) transporters expressed at the blood-brain barrier (BBB) impede delivery of therapeutic agents to the brain, including agents to treat neurodegenerative diseases and primary and metastatic brain cancers. Two transporters, ABCB1 and ABCG2, are highly expressed at the BBB and are responsible for the efflux of numerous clinically useful chemotherapeutic agents, including irinotecan, paclitaxel, and doxorubicin. Based on a previous mouse model, we have generated transgenic zebrafish in which expression of NanoLuciferase (NanoLuc) is controlled by the promoter of glial fibrillary acidic protein, leading to expression in zebrafish glia.
View Article and Find Full Text PDFGlioblastoma (GBM) is hard to treat due to cellular invasion into functioning brain tissues, limited drug delivery, and evolved treatment resistance. Recurrence is nearly universal even after surgery, chemotherapy, and radiation. Photodynamic therapy (PDT) involves photosensitizer administration followed by light activation to generate reactive oxygen species at tumor sites, thereby killing cells or inducing biological changes.
View Article and Find Full Text PDFATP-binding cassette (ABC) transporters expressed at the blood-brain barrier (BBB) impede delivery of therapeutic agents to the brain, including agents to treat neurodegenerative diseases and primary and metastatic brain cancers. Two transporters, P-glycoprotein (P-gp, ABCB1) and ABCG2, are highly expressed at the BBB and are responsible for the efflux of numerous clinically useful chemotherapeutic agents, including irinotecan, paclitaxel, and doxorubicin. Based on a previous mouse model, we have generated transgenic zebrafish in which expression of NanoLuciferase (NanoLuc) is controlled by the promoter of glial fibrillary acidic protein, leading to expression in zebrafish glia.
View Article and Find Full Text PDFBreast cancer is the most diagnosed cancer type in women, with it being the second most deadly cancer in terms of total yearly mortality. Due to the prevalence of this disease, better methods are needed for both detection and treatment. Reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) are autofluorescent biomarkers that lend insight into cell and tissue metabolism.
View Article and Find Full Text PDFIEEE J Sel Top Quantum Electron
September 2020
The blood-brain barrier (BBB) remains a major obstacle for drug delivery to the central nervous system. In particular, the tight and adherens junctions that join the brain capillary endothelial cells limit the diffusion of various molecules from the bloodstream into the brain. Photodynamic priming (PDP) is a non-cytotoxic modality that involves light activation of photosensitizers to photochemically modulate nearby molecules without killing the cells.
View Article and Find Full Text PDFSignificance: Previous studies have been performed to image photosensitizers in certain organs and tumors using fluorescence laminar optical tomography. Currently, no work has yet been published to quantitatively compare the signal compensation of fluorescence laminar optical tomography with two-dimensional (2-D) imaging in tissues.
Aim: The purpose of this study is to quantify the benefit that fluorescence laminar optical tomography holds over 2-D imaging.
Background: The endothelial cell-cell junctions of the blood-brain barrier (BBB) play a pivotal role in the barrier's function. Altered cell-cell junctions can lead to barrier dysfunction and have been implicated in several diseases. Despite this, the driving forces regulating junctional protein presentation remain relatively understudied, largely due to the lack of efficient techniques to quantify their presentation at sites of cell-cell adhesion.
View Article and Find Full Text PDFNanomaterials (Basel)
January 2020
Liposomes hold great potential as gene and drug delivery vehicles due to their biocompatibility and modular properties, coupled with the major advantage of attenuating the risk of systemic toxicity from the encapsulated therapeutic agent. Decades of research have been dedicated to studying and optimizing liposomal formulations for a variety of medical applications, ranging from cancer therapeutics to analgesics. Some effort has also been made to elucidate the toxicities and immune responses that these drug formulations may elicit.
View Article and Find Full Text PDFFluorescence-guided surgery (FGS) is routinely utilized in clinical centers around the world, whereas the combination of FGS and photodynamic therapy (PDT) has yet to reach clinical implementation and remains an active area of translational investigations. Two significant challenges to the clinical translation of PDT for brain cancer are as follows: (1) Limited light penetration depth in brain tissues and (2) Poor selectivity and delivery of the appropriate photosensitizers. To address these shortcomings, we developed nanoliposomal protoporphyrin IX (Nal-PpIX) and nanoliposomal benzoporphyrin derivative (Nal-BPD) and then evaluated their photodynamic effects as a function of depth in tissue and light fluence using rat brains.
View Article and Find Full Text PDFPhotosensitizing biomolecules (PSBM) represent a new generation of light-absorbing compounds with improved optical and physicochemical properties for biomedical applications. Despite numerous advances in lipid-, polymer-, and protein-based PSBMs, their effective use requires a fundamental understanding of how macromolecular structure influences the physicochemical and biological properties of the photosensitizer. Here, we prepared and characterized three well-defined PSBMs based on a clinically used photosensitizer, benzoporphyrin derivative (BPD).
View Article and Find Full Text PDFSemin Thorac Cardiovasc Surg
November 2018
Erythrocyte storage induces a nonphysiological increase in hemoglobin-oxygen affinity (quantified by low p50, the oxygen tension at 50% hemoglobin saturation), which can be restored through biochemical rejuvenation. The objective was to mathematically model the impact of transfusing up to 3 standard allogeneic units or rejuvenated units on oxygen delivery (DO) and oxygen consumption (VO). Oxygen dissociation curves were generated from additive solution-1 red blood cell (RBC) leukoreduced units (n = 7) before and after rejuvenation following manufacturer's instructions.
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