The memory deficits associated with Alzheimer's disease result to a great extent from hippocampal network dysfunction. The coordination of this network relies on theta (symbol) oscillations generated in the medial septum. Here, we investigated in rats the impact of hippocampal amyloid beta (Abeta) injections on the physiological and cognitive functions that… (More)
In Alzheimer's disease, amyloid beta peptide (Aβ) accumulation is associated with hippocampal network dysfunction. Intrahippocampal injections of Aβ induce aberrant inhibitory septohippocampal (SH) network activity in vivo and impairment of memory processing. In the present study, we observed, after hippocampal Aβ treatment, a selective loss of neurons… (More)
The memory deficits associated with Alzheimer's disease result to a great extent from hippocampal network dysfunction. The coordination of this network relies on theta () oscillations generated in the medial septum. Here, we investigated in rats the impact of hippocam-pal amyloid ␤ (A␤) injections on the physiological and cognitive functions that depend on… (More)
A method for reconstructing magnetic resonance angiography (MRA) volumes from successive acquisitions is described. The method is based on double oblique acquisitions of highly anisotropic MRA volumes, each of which corresponds to reduced k-space filling. These partial k-spaces are then combined to obtain a 3D k-space adapted to the frequency spread of the… (More)
In the field of color image calibration, several image transformation models are used, among which the linear model, the affine model, or the quadratic model; we show that the linear algebraic model is the most natural model under the usual assumptions on the image formation and we provide the detailed mathematical justification. Then we examine the… (More)
A statistical methodology is proposed to rank several estimation methods of a relevant clinical parameter when no gold standard is available. Based on a regression without truth method, the proposed approach was applied to rank eight methods without using any a priori information regarding the reliability of each method and its degree of automation. It was… (More)
In this paper, a previously developed segmentation algorithm was improved by adding a fully automated definition of a region of interest around the left ventricle.
A fully automated segmentation method of the left ventricle from short-axis cardiac MR images is proposed and evaluated. The segmentation is based on morphological filtering and gradient vector flow snake for which an automatic setting of parameters has already been proposed. The present work focuses on the automatic detection of a region of interest (ROI)… (More)