The whole imaging process lasted 180 seconds to capture tumor perfusion of NB agents and was recorded on the hard disk of the scanner for post-imaging review. Images were then saved in the DICOM format. The regions of interests (ROIs) were given as the whole areas of tumors and analyzed by the QLAB software (Figure 5B). The change in NB signal intensity, the size of perfusion areas, and other parameters (arrival time, time to peak, and area under the curve) of the time-intensity curve (TIC) were also uploaded to QLAB for analysis. The average intensity of NBs was repeated three times at each point over the entire protocol. We calculated changes of these parameters before and during the study to compare

their differences statistically. At the end of the protocol (day 8), mice were killed, and

tumor samples were excised, fixed in formalin solution, embedded in paraffin, and then sliced selleckchem into 5-μm sections using a microtome. Samples were stained by hematoxylin LY294002 and eosin to visualize the tumor necrosis within different groups. The anti-murine caspase-3 p11 antibody (Santa Cruz Biotechnology, Inc) was used for histochemistry to detect the cell apoptosis in tumors (Figure 5A). The immunoreaction for caspase-3 and Her-2 (anti–Her-2 antibody; Abcam) in tumor cells was determined by two pathologists (P.Y. and C.R.F.), and the consensus was reached for the final diagnosis. The scores and percentage of tumor cells stained are described as follows [5] and [6]: no positive cells (−), 1% to 10% of the cells stained (+), 11% to 50% of cells stained (++), and 51% to 100% of the cells stained (+++). We then calculated the percentage of number of mice Sunitinib manufacturer with positive caspase-3 and Her-2 expression in each

group and described them by bars. Comparison with the average mean and peak NB intensities analyzed by the software after the treatment was carried out to find the correlation between NB intensities and IHC results. Statistical analyses were performed with SPSS statistical software package (17.0 version; SPSS Inc, Chicago, IL). Data were summarized as means ± standard error. In vitro, count data were analyzed in the assessment of the intergroup comparison with a two-sample independent t-test. Analyses of mouse weight and tumor size or parameters of ultrasound imaging were compared between groups with multiple comparison in analysis of variance (Student-Newman-Keuls test or least significant difference procedure test). A correlation between histologic and imaging experimental data was performed by Pearson correlation test. A P value below .05 was considered significant. As Figure 1B showed, the NBs prepared before was well distributed and uniformed, which was described as a normal distributed curve ( Figure 1A), and the mean sizes of NB was 586 ± 6.0 nm. After the trastuzumab administration, the binding rate of targeted NB with human breast cancer apoptotic cells was higher than that of the control group (79.