Fig. 1.

ND infusion and vaporization increases contrast in the pancreas prior to T1D. (A) Size distribution of size-isolated microbubbles prior to condensation and of NDs following condensation. (B) Representative B-mode images of the abdomen, indicating the two regions in which vaporization was performed (pancreas, green; kidney, yellow), as well as the spleen anatomical landmarks used to identify the pancreas. (C) Schematic of ND imaging protocol, where time courses are recorded prior to ND infusion (preinfusion). After ND infusion, acquisition is paused to allow the NDs to accumulate in tissues with permeable microvasculature and clear from the bloodstream. Following the pause, time courses are then recorded for 10 min, during which droplets are vaporized. (D) Representative B-mode and subharmonic contrast images of pancreas (green) and spleen (purple) before ND infusion and 30 min after ND infusion. (E) As in D of the kidney. (F) Time-course of mean contrast signal, normalized to background, in the pancreas and kidney of 10-wk-old female NOD mice following ND infusion and vaporization. (G) Mean contrast signal averaged between 30 and 35 min following ND infusion for the pancreas, kidney, and spleen. Dashed lines in F represent 95% CI, error bars in G represent SEM. Data in F and G are representative of n = 26 mice (pancreas) and n = 13 mice (kidney). The P values in G are 0.0009 (***P < 0.001) comparing pancreas versus kidney and 0.0001 (***P < 0.001) comparing pancreas versus spleen (paired Student’s t test). In G, an outlier data point (pancreas, S−B/B = 10.79) is not shown.