Materials and Methods: Animal studies were approved by the Institutional Administrative Panel on Laboratory Vactosertib price Animal Care. A heterodimeric peptide that binds to human KDR with low nanomolar affinity

(K(D) = 0.5 nmol/L) was coupled onto the surface of perfluorobutane-containing lipid-shelled MBs (MB(KDR)). Binding specificity of MB(KDR) to human KDR and cross-reactivity with murine vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) were tested in cell culture under flow shear stress conditions (at 100 sec 2 1). In vivo binding specificity of MB(KDR) to VEGFR2 was tested in human LS174T colon cancer xenografts in mice with a 40-MHz ultrasonographic (US) transducer. Targeted contrast material-enhanced US imaging signal by using MB(KDR) was longitudinally measured during 6 days in tumors with (n = 6) and without (n = 6) antiangiogenic treatment (anti-VEGF antibody). Ex vivo VEGFR2 staining and microvessel density analysis were performed. Significant differences were Selleck Birinapant evaluated (t, Mann-Whitney, or Wilcoxon test).

Results: Cell

culture experiments showed four times greater binding specificity of MB(KDR) to human KDR and cross-reactivity to murine VEGFR2 (P <= .01). In vivo imaging signal was more than three times higher (P = .01) with MB(KDR) compared with control MBs and decreased significantly (approximately fourfold lower, P = .03) following in vivo receptor blocking with anti-VEGFR2 antibody. One day after initiation of antiangiogenic therapy, imaging signal was significantly decreased (approximately 46% lower, P = .02) in treated versus untreated tumors; it remained significantly lower (range, 46%-84% decreased; P = .038) during the following 5 days. Microvessel density was significantly reduced (P = .04) in treated (mean, 7.3 microvessels Sapanisertib per square millimeter +/- 4.7 [standard deviation]) versus untreated tumors (mean, 22.0 microvessels per square millimeter 6 9.4); VEGFR2 expression was significantly decreased (>50% lower, P = .03) in treated tumors.

Conclusion: Human MB(KDR) allow

in vivo imaging and longitudinal monitoring of VEGFR2 expression in human colon cancer xenografts. (C) RSNA, 2010″
“A network analyzer connected to a high pressure vessel was used to measure the conductance spectrum in a wide range of frequency (1-250 MHz) of an AT-cut quartz crystal resonator of nominal frequency 3 and 5 MHz totally immersed in a fluid under pressure ranging from atmospheric pressure to 80 MPa. Measurements carried out with several gases (methane, nitrogen, argon, carbon dioxide) and various hydrocarbon liquids (toluene, heptane, nonane, decane, dodecane) show that quartz resonators correctly work when they are fully immersed in pressurized fluids whatever the state gas or liquid and whatever the pressure.