Alan C McLaughlin

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Steady-state arterial spin tagging approaches can provide quantitative images of CBF, but have not been validated in humans. The work presented here compared CBF values measured using steady-state arterial spin tagging with CBF values measured in the same group of human subjects using the H(2)(15)O IV bolus PET method. Blood flow values determined by(More)
The Stern equation, a combination of the Langmuir adsorption isotherm, the Boltzmann relation, and the Grahame equation from the theory of the diffuse double layer, provides a simple theoretical framework for describing the adsorption of charged molecules to surfaces. The ability of this equation to describe the adsorption of divalent cations to membranes(More)
Phase-encoded multishot SPIRAL approaches were used to acquire true 3D cerebral blood flow images of the human head using arterial spin tagging approaches. Multiple-inversion background suppression techniques, which suppress phase noise due to interacquisition fluctuations in the static magnetic field, reduced the temporal standard deviation of true 3D(More)
The electrostatic properties of charged bilayers and the bilayer component of biological membranes are often described theoretically by assuming the charge is smeared uniformly over the surface. This is one of the fundamental assumptions in the Gouy-Chapman-Stern (GCS) theory. However, the average distance between the charged phospholipids in a typical(More)
A method is presented for multislice measurements of quantitative cerebral perfusion based on magnetic labeling of arterial spins. The method combines a pulsed arterial inversion, known as the FAIR (Flow-sensitive Alternating Inversion Recovery) experiment, with a fast spiral scan image acquisition. The short duration (22 ms) of the spiral data collection(More)
PURPOSE To assess the reliability and sensitivity of gradient-echo, isotropic multisection echo-planar magnetic resonance (MR) imaging for within-subject whole-brain mapping. MATERIALS AND METHODS Eight right-handed healthy volunteers underwent gradient-echo, echo-planar MR imaging while they performed a motor task on three occasions over 2-3 months.(More)
"Vascular" artifacts can have substantial effects on human cerebral blood flow values calculated by using arterial spin tagging approaches. One vascular artifact arises from the contribution of "tagged" arterial water spins to the observed change in brain water MR signal. This artifact can be reduced if large bipolar gradients are used to "crush" the MR(More)
We used 17O NMR imaging techniques to measure the H2(17)O concentration in a 0.8-ml voxel in the cat brain following injection of an arterial bolus of enriched H2(17)O and during inhalation of enriched 17O2. We also measured the H2(17)O concentration in arterial blood during 17O2 inhalation. The data from the first measurement were used to calculate the(More)
The effect of the nitric oxide (NO) synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) on the response of cerebrocortical oxygen consumption (CMRO2) and blood flow (CBF) to two levels of hypercapnia (PaCO2 approximately 60 mm Hg and PaCO2 approximately 90 mm Hg) was investigated in ketamine-anesthetized rats. CBF was calculated using the(More)
Electrophoretic mobility and 31P NMR measurements were combined to test whether the combination of the Henry, Boltzmann and Grahame equations is capable of describing the adsorption of divalent cations of phosphatidylcholine membranes. Cobalt was chosen for this study because, of all the common divalent cations, its effects on the 31P NMR spectrum of(More)