Publications by authors named "Jeffrey Muenzer"

Objective: Vancomycin loading doses are recommended; however, the risk of nephrotoxicity with these doses is unknown. The primary objective of this study was to compare nephrotoxicity in emergency department (ED) sepsis patients who received vancomycin at high doses (>20 mg/kg) versus lower doses (≤20 mg/kg).

Methods: A retrospective cohort study was performed in three academic EDs.

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Objectives: Ventricular remodeling after myocardial infarction begins with massive extracellular matrix deposition and resultant fibrosis. This loss of functional tissue and stiffening of myocardial elastic and contractile elements starts the vicious cycle of mechanical inefficiency, adverse remodeling, and eventual heart failure. We hypothesized that stromal cell-derived factor 1α (SDF-1α) therapy to microrevascularize ischemic myocardium would rescue salvageable peri-infarct tissue and subsequently improve myocardial elasticity.

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Background: Experimentally, exogenous administration of recombinant stromal cell-derived factor-1α (SDF) enhances neovasculogenesis and cardiac function after myocardial infarction. Smaller analogs of SDF may provide translational advantages including enhanced stability and function, ease of synthesis, lower cost, and potential modulated delivery via engineered biomaterials. In this study, computational protein design was used to create a more efficient evolution of the native SDF protein.

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This study evaluates a therapy for infarct modulation and acute myocardial rescue and utilizes a novel technique to measure local myocardial oxygenation in vivo. Bone marrow-derived endothelial progenitor cells (EPCs) were targeted to the heart with peri-infarct intramyocardial injection of the potent EPC chemokine stromal cell-derived factor 1α (SDF). Myocardial oxygen pressure was assessed using a noninvasive, real-time optical technique for measuring oxygen pressures within microvasculature based on the oxygen-dependent quenching of the phosphorescence of Oxyphor G3.

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Objectives: Stromal cell-derived factor (SDF)-1α is a potent endogenous endothelial progenitor cell (EPC) chemokine and key angiogenic precursor. Recombinant SDF-1α has been demonstrated to improve neovasculogenesis and cardiac function after myocardial infarction (MI) but SDF-1α is a bulky protein with a short half-life. Small peptide analogs might provide translational advantages, including ease of synthesis, low manufacturing costs, and the potential to control delivery within tissues using engineered biomaterials.

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Background: Myocardial ischemia causes cardiomyocyte death, adverse ventricular remodeling, and ventricular dysfunction. Endothelial progenitor cells (EPCs) have been shown to ameliorate this process, particularly when activated with stromal cell-derived factor-1α (SDF), known to be the most potent EPC chemokine. We hypothesized that implantation of a tissue-engineered extracellular matrix (ECM) scaffold seeded with EPCs primed with SDF could induce borderzone neovasculogenesis, prevent adverse geometric remodeling, and preserve ventricular function after myocardial infarction.

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Objective: Microvascular malperfusion after myocardial infarction leads to infarct expansion, adverse remodeling, and functional impairment. Native reparative mechanisms exist but are inadequate to vascularize ischemic myocardium. We hypothesized that a 3-dimensional human fibroblast culture (3DFC) functions as a sustained source of angiogenic cytokines, thereby augmenting native angiogenesis and limiting adverse effects of myocardial ischemia.

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