Publications by authors named "Jason R Roberts"

Background: Preservative-free tobramycin is commonly used as aerosolized therapy for ventilator associated pneumonia. The comparative delivery profile of the formulations of two different concentrations (100 mg/ml and 40 mg/ml) is unknown. This study aims to evaluate the aerosol characteristics of these tobramycin formulations in a simulated adult mechanical ventilation model.

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Here we demonstrate an approach to stabilize enzymes through the orthogonal covalent attachment of albumin on the single-enzyme level. Albuminated glycoenzymes (AGs) based upon glucose oxidase and catalase from Aspergillus niger were prepared in this manner. Gel filtration chromatography and dynamic light scattering support modification, with an increase in hydrodynamic radius of ca.

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Background: Continuous glucose monitors (CGMs) require percutaneous wire probes to monitor glucose. Sensors based on luminescent hydrogels are being explored as fully implantable alternatives to traditional CGMs. Our previous work investigated hydrogel matrices functionalized with enzymes and oxygen-quenched phosphors, demonstrating sensitivity to glucose, range of response, and biofouling strongly depend on the matrix material.

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The role of artificial sweeteners in the management of obesity is controversial. Observational data have suggested that nonnutritive sweeteners (NNSs) may promote weight gain through poorly understood mechanisms of cravings, reward phenomenon, and addictive behavior via opioid receptors. Interventional studies suggest the opposite that substitution of NNS for sugar-sweetened beverages (SSBs) results in reduced caloric intake and modest degrees of weight loss.

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Endoscopy plays an important role in both the diagnosis and the initial management of recurrent acute pancreatitis, as well as the investigation of refractory disease, but it has known limitations and risks. Sound selective use of these therapies, complemented with other lines of investigation such as genetic testing, can dramatically improve frequency of attacks and associated quality of life. Whether endoscopic therapy can reduce progression to chronic pancreatitis, or reduce the risk of malignancy, is debatable, and remains to be proven.

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This study demonstrates the successful manufacture and functional characterization of alginate hydrogels containing a variety of encapsulates within polyelectrolyte multilayer-coated micropores. These microporous alginate (MPA) hydrogels are prepared one-step internal ionotropic gelation of the alginate using polyelectrolyte multilayer-coated CaCO microspheres along with the weak acid glucono-δ-lactone. Here, successful encapsulation of a model macromolecule and fluorescent nanoparticles within microcapsules-distributed throughout the larger alginate hydrogel-is confirmed with confocal microscopy, while the porous morphology of the MPA hydrogels is examined with scanning electron microscopy.

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Targeted PEGylation of glucose oxidase at its glycosylation sites was investigated to determine the effect on enzymatic activity, as well as the bioconjugate's potential in an optical biosensing assay. Methoxy-poly(ethylene glycol)-hydrazide (4.5kDa) was covalently coupled to periodate-oxidized glycosylation sites of glucose oxidase from Aspergillus niger.

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Background: Continuous glucose monitoring is crucial to developing a successful artificial pancreas. However, biofouling and host response make in vivo sensor performance difficult to predict. We investigated changes in glucose diffusivity and sensor response of optical enzymatic glucose sensors due to biological exposure.

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