Claire A. Sheldon

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Despite the popularity of Na+-binding benzofuran isophthalate (SBFI) to measure intracellular free Na+ concentrations ([Na+](i)), the in situ calibration techniques described to date do not favor the straightforward determination of all of the constants required by the standard equation (Grynkiewicz G, Poenie M, and Tsien RY. J Biol Chem 260: 3440-3450,(More)
NMDA-type glutamate receptors play a critical role in neuronal synaptogenesis, plasticity, and excitotoxic death. Recent studies indicate that functional NMDA receptors are also expressed in certain glial populations in the normal brain. Using immunohistochemical methods, we detected the presence of the NMDA receptor 2B (NR2B) subunit of the NMDA receptor(More)
Mechanisms that contribute to Na+ influx during and immediately after 5 min anoxia were investigated in cultured rat hippocampal neurons loaded with the Na+-sensitive fluorophore sodium-binding benzofuran isophthalate. During anoxia, an influx of Na+ in the face of reduced Na+,K+-ATPase activity caused a rise in [Na+]i. After the return to normoxia,(More)
Whole-exome sequencing and autozygosity mapping studies, independently performed in subjects with defective combined mitochondrial OXPHOS-enzyme deficiencies, identified a total of nine disease-segregating FBXL4 mutations in seven unrelated mitochondrial disease families, composed of six singletons and three siblings. All subjects manifested early-onset(More)
The ratiometric indicators 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein and Fura-2 were employed to examine, respectively, intracellular pH (pHi) and calcium ([Ca2+]i) changes evoked by anoxia in cultured postnatal rat hippocampal neurons at 37 degrees C. Under both HCO3-/CO2- and HEPES-buffered conditions, 3-, 5- or 10-min anoxia induced a(More)
The reading of text is predominantly a left hemisphere function. However, it is also possible to process text for attributes other than word or letter identity, such as style of font or handwriting. Anecdotal observations have suggested that processing the latter may involve the right hemisphere. We devised a test that, using the identical stimuli, required(More)
We report a method for the concurrent measurement of intracellular [Na+] ([Na+]i) and pH (pHi) in cells co-loaded with SBFI, a Na+-sensitive fluorophore, and either carboxy SNARF-1 or SNARF-5F, H+-sensitive fluorophores. With the optical filters specified, fluorescence emissions from SBFI and either SNARF derivative were sufficiently distinct to allow the(More)
BACKGROUND Current cognitive models propose that multiple processes are involved in reading and writing. OBJECTIVE Our goal was to use linguistic analyses to clarify the cognitive dysfunction behind two classic alexic syndromes. METHODS We report four experiments on two patients, one with alexia without agraphia following occipitotemporal lesions, and(More)
The effect of anoxia on Na+/H+ exchange activity was examined in acutely isolated adult rat hippocampal CA1 neurons loaded with the H+-sensitive fluorophore, BCECF. Five-minute anoxia imposed under nominally HCO3-/CO2-free conditions induced a fall in pHi, the magnitude of which was smaller following prolonged exposure to medium in which(More)
The effects of anoxia on intracellular pH (pH(i)) were examined in acutely isolated adult rat hippocampal CA1 neurons loaded with the H(+)-sensitive fluorophore, 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein. During perfusion with HCO/CO(2)- or HEPES-buffered media (pH 7.35) at 37 degrees C, 5- or 10-min anoxic insults were typified by an(More)