BSA-based macromolecular contrast material, biotin2-BSA-gadolini-um-DTPA23 (biotin-BSA-GdDTPA; about 82 kDa) was prepared as reported previously and bolus injected through a tail vein catheter (12.4 mg/mouse in 0.2 ml).
A series of precontrast spin echo images, with repetition time (TR) values of 1000, 500, 200, and 100 msec, were acquired to determine the precontrast R1. For dynamic postcontrast imaging, T1 weighted spin echo images were obtained 4-32 min after the contrast agent was administered (TR 200 msec, echo time 10.6 msec, two averages, spectral width 50 000 Hz, field of view 35 mm, slice thickness 1 mm, matrix 256 X 256, in plane resolution 137 |xm, acquisition time 105 sec).
At the end of the MRI measurements, mice were killed by anesthesia overdose, and the grafts were retrieved for histological analysis. canadian pharmacy cialis
Analysis of the Dynamic MR Data
MR data were analyzed on an Indigo-2 O2 work station (Silicon Graphics, Mountain View, CA) using Matlab (MathWorks Inc., Natick, MA). Pixel-by-pixel analysis was used to generate concentration maps of biotin-BSA-GdDTPA from spin-echo data sets as reported.