Frank E Hospod

Learn More
A reliable, accurate, and accessible method for measuring cerebral blood volume (CBV) has been developed based on T(*) (2)-weighted MRI and a 1-min infusion of gadolinium instead of a bolus. Computer simulations predict that this infusion CBV method will have a signal-to-noise ratio (SNR) 3-5 times greater than that obtained by area-under-the-curve (AUC)(More)
Hypothalamic brain slices, varying in thickness from 400 mu to 1,000 mu, were assessed by studying 2-deoxyglucose (2DG) metabolism, lactate accumulation, inulin spaces, and morphology at the light and ultrastructural levels. Evidence of increased glycolytic flux due to anaerobic metabolism is found at thickness greater than 600 mu in association with a(More)
Estimates of cerebral blood volume (CBV) obtained from dynamic contrast T2(*)-weighted magnetic resonance imaging (MRI) tend to be significantly higher than values obtained by other methods. This may relate to the common assumption that the proportionality constants relating signal change to contrast concentration are equal in tissue and artery. To test(More)
We describe an approach to measuring cerebral blood flow (CBF) based on independent measurements of cerebral blood volume (CBV) and mean transit time (MTT) with calculation of CBF by using the central volume theorem: CBF = CBV / MTT. This permits optimization of the individual acquisitions and analyses. In particular, measurement of CBV during contrast(More)
Hippocampal brain slices are valuable models for studying brain function but are compromised by several artifacts, including significant water gain and histologic injury, which occur under certain incubation conditions. Addition of colloid to Krebs-Ringer buffer (K-R) has been shown to eliminate water gain but has not achieved widespread acceptance. We(More)
Diffusion in the extracellular space (ECS) is important in physiologic and pathologic brain processes but remains poorly understood. To learn more about factors influencing tissue diffusion and the role of diffusion in solute-tissue interactions, particularly during cerebral ischemia, we have studied the kinetics of several radiotracers in control and(More)
An in vitro glucose utilization method, based upon 14C-2-deoxyglucose kinetics in brain slices, has been used to study circadian rhythms in hypothalamic slices containing the suprachiasmatic nucleus (SCN). Spontaneous SCN metabolic activity in vitro is similar to that observed in vivo with higher metabolic rates in subjective daytime and lower rates during(More)
Altered calcium homeostasis is likely to play a pathogenetic role in cerebral ischemia. In order to further understand which factors associated with ischemia contribute to disturbances of calcium metabolism, the influence of 3 isolated insults, 8 mM K+, pH 6.1 and 1 mM glutamate, on total tissue calcium were studied by analysis of steady-state kinetics of(More)
Using a hypothalamic slice preparation containing the suprachiasmatic nucleus (SCN) and measurement of 2-deoxy[14C]glucose (2-DG) uptake by autoradiography, we have demonstrated that, after 1 h in vitro, 2-DG uptake into the SCN is proportional to the rate of glucose utilization present in vivo at the corresponding subjective time of day and that, during an(More)
Brain slices of varying thickness were used to modify retention of metabolic products in an in vitro model of ischemia. Past and present results reveal increased anaerobic glycolysis in 660-microns slices with accumulation of lactate as slice thickness reaches 1,000 microns. Brain slice glucose utilization and lactate content were measured in buffers of(More)