Publications by authors named "Vincent A Bourke"

pH plays an important role in tumor proliferation, angiogenesis, metabolic control, and the efficacy of cytotoxic therapy, and accurate noninvasive assessment of tumor pH promises to provide insight into developmental processes and prognostic information. In this paper, we report the design, synthesis, and characterization of two novel pH indicators 6-trifluoromethylpyridoxine 8 and α(4),α(5)-di-O-[3'-O-(β-d-glucopyranosyl)propyl]-6-trifluoromethylpyridoxine 17 and demonstrate 8 as an extracellular (19)F NMR pH probe to assess pH(e) of various tumors in vivo.

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This report evaluates the spatial profile of blood vessel fragments (BVFs) and CD34(+) and CD117(+) hematopoietic stem and progenitor cells (HSPCs) in human cancellous bone. Bone specimens were sectioned, immunostained (anti-CD34 and anti-CD117), and digitally imaged. Immunoreactive cells and vessels were then optically and morphometrically identified and labeled on the corresponding digital image.

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Unlabelled: Current bone marrow dosimetry methods inherently assume that the target cells of interest for the assessment of leukemia risk (stochastic effects) or marrow toxicity (deterministic effects) are uniformly localized throughout the marrow cavities of cancellous bone. Previous studies on mouse femur, however, have demonstrated a spatial gradient for the hematopoietic stem and progenitor cells, with higher concentrations near the bone surfaces. The objective of the present study was to directly measure the spatial concentration of these cells, as well as marrow vasculature structures, within images of human disease-free bone marrow.

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Purpose: To investigate the application of pretreatment oxygenation to the AT1 subline of the Dunning R3327 prostate tumor, which is more hypoxic and faster growing than the H1 subline previously studied.

Methods And Materials: Dunning prostate R3327-AT1 tumors growing on Copenhagen rats were administered 30 Gy of X-ray radiation either with or without oxygen inhalation. Tumor oxygenation was sampled by (19)F nuclear magnetic resonance echo planar imaging relaxometry of the reporter molecule hexafluorobenzene, no more than 24 h before irradiation.

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The simultaneous measurement of three oxygen-sensitive parameters [arterial hemoglobin oxygen saturation (SaO2), tumor vascular-oxygenated hemoglobin concentration ([HbO2]), and tumor oxygen tension (pO2)] in response to hyperoxic respiratory challenge is demonstrated in rat breast tumors. The effects of two hyperoxic gases [oxygen and carbogen (5% CO2 and 95% O2)] were compared, by use of two groups of Fisher rats with subcutaneous 13762NF breast tumors implanted in pedicles on the foreback. Two different gas-inhalation sequences were compared, i.

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