Image fty720 PP2a acquisition Imaging was performed on a 3-Tesla Trio MR scanner (Siemens Medical Systems, Erlangen, Germany) in the Institute of Neuroscience and Biophysics—Medicine, Research Center Jülich. Subjects for the scans were chosen due to their genotype. Head movements were minimized by immobilizing the head during the scanning procedure using foam cushions. Images were acquired with a diffusion-weighted (DW) double spin-echo echo planar imaging sequence (echo time 89 msec; 1.8 mm isotropic resolution). A
12-channel phased-array coil was used and the sequence Inhibitors,research,lifescience,medical utilized twofold acceleration with the GRAPPA parallel imaging technique (Griswold et al. 2002). Sixty different gradient directions distributed over the unit sphere according to the Jones-scheme were acquired with a b-value of 800 sec/mm2, in addition seven interleaved acquisitions of non-DW images (b = 0). The protocol was acquired four times Inhibitors,research,lifescience,medical and, after individual motion correction, the DW images
were averaged to increase the signal-to-noise-ratio. In addition, an anatomical T1-weighted magnetization Inhibitors,research,lifescience,medical prepared rapid gradient echo sequence was acquired (1 mm isotropic resolution). Image preprocessing We selleck bio followed the standard protocol by Smith and colleagues (Smith et al. 2007). First, data sets were corrected for head motion and eddy currents. Then, a diffusion tensor model was fit to the set Inhibitors,research,lifescience,medical of diffusion-weighted images, before calculating FA maps for each subject. All FA images were visually checked for artefacts, intensity range problems, and general data quality. TBSS analysis After visual assessment, we used the FSL TBSS scripts (http://www.fmrib.ox.ac.uk/fsl/tbss) on the individual
FA maps (Smith et al. 2006, 2007). All individual FA maps were nonlinearly registered to each other to determine the “most typical” subject of each group. After identification of the “most typical” subject as the target, all other FA images were aligned to it and then transformed into 1 × 1 × 1 mm3 MNI152 space. All subsequent processing was carried out using this space and resolution. The Inhibitors,research,lifescience,medical transformed images were averaged to create a mean FA image, which was then fed into the tract skeleton generation, resulting in an FA skeleton aiming to represent all fiber tracts common to all subjects included in the study. To restrict further analysis to the white matter, a Drug_discovery skeleton threshold of FA > 0.2 was applied (Smith et al. 2007). Then, the nearest local FA maxima of each individual FA image were projected onto the mean FA skeleton. This process of registration helps to increase sensitivity and interpretability of results yielded by DT imaging. For example, ventricular enlargement caused by a pathophysiological process can notably mislead the interpretation of the results of a voxel-based voxel-based morphometry (VBM)-style DTI analysis (Smith et al. 2007).