Publications by authors named "Randy L Tyson"

We present the design of an integrated system for performing both real and virtual (simulated) magnetic resonance imaging (MRI) experiments. We emphasize the approaches used to maximize the level of integration and also the benefits that tight real-virtual integration brings for a scientific instrument. The system has been implemented for both low field (0.

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Objective: To study the effect of hypothermia on metabolic compartmentalization in an animal model.

Methods: [1-(13)C] glucose, [2-(13)C] glucose, [3-(13)C] lactate, and [2-(13)C] acetate were infused into male Sprague-Dawley rats. The (13)C label was detected using (13)C-edited H magnetic resonance spectroscopy or (13)C magnetic resonance spectroscopy to determine the isotopic enrichment of both glutamate and glutamine.

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There is a misconception that hypoglycemic nerve cell death occurs easily, and can happen in the absence of coma. In fact, coma is the prerequisite for neuronal death, which occurs via metabolic excitatory amino acid release. The focus on nerve cell death does not explain how most brain neurons and all glia survive.

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[1-13C]Glucose, [2-13C]acetate and [3-13C]lactate were infused into male Sprague-Dawley rats (150-170 g) for periods of 3-100 min (n=4 per time) and neocortex extracts were analyzed using 13C-edited 1H magnetic resonance (MR) spectroscopy. The time dependence of the [4-13C]glutamine/[4-13C]glutamate labeling ratio was significantly different for all three substrates infused (p<0.001) and showed that acetate is primarily utilized by glia and lactate by neurons, whereas glucose is ubiquitous.

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