3.5. Effect of Liposome Concentration on HGF Protein Production by Sonoporated Cardiomyocytes HGF protein concentration in the culture medium was 0.53 ± 0.053ng/mL/mg and was nominally highest when the liposome concentration was 1 × 107particles/mL and insonification consisted of three 30-sec ultrasound exposures,

though it was statistically similar to that obtained with 1 × 106particles/mL. At a higher liposome concentration of 1 × 108particles/mL, HGF protein concentration decreased (Figure 3(e)). 3.6. Effect of HIF activation Repetition of Insonification Inhibitors,research,lifescience,medical on HGF Protein Production by Sonoporated Cardiomyocytes HGF protein concentration in the culture medium was 0.54 ± 0.053ng/mL/mg and was highest when three 30-sec insonifications were given, with a liposome concentration of 1 × 107particles/mL and 60mg DNA. This protein production was statistically higher Inhibitors,research,lifescience,medical than in cells given one or five insonifications (Figure 3(f)). 3.7. Effect of Insonification Time on Cell Viability The percentage of dead cells was 14.7 ± 0.9% and was higher in the cells given five 30-sec insonifications at a liposome concentration of 1 × 107particles/mL (Figure 4(a)). There was no statistical Inhibitors,research,lifescience,medical difference between 30- and 60-sec insonification. Figure 4 (a) Effect of insonification time on cell viability using 60μg of DNA, 1 × 107particles/mL liposome, and

15-min incubation with DNA, and three 30- or 60-sec insonifications. “US alone” represents the percentage … 3.8. Effect of Liposome Concentration on Cell Viability The percentage of dead cells increased with increasing concentrations Inhibitors,research,lifescience,medical of liposome (Figure 4(b)). The dead cell count was 24.8 ± 2.9% and was highest when the liposome concentration was 1 × 108particles/mL and three 30-sec insonifications were used. 3.9. Effect of Number of Insonification Repetitions on Cell

Viability The percentage of dead cells increased as the number of insonification repetitions increased (Figure 4(c)). The dead cell Inhibitors,research,lifescience,medical count was 14.7 ± 0.9 % and was highest when five repetitions of the insonification step were given, with a liposome concentration of 1 × 107particles/mL. 3.10. Scanning Electron Microscopy Observations second of Sonoporated Cardiomyocytes No particular changes were evident on the surfaces of untreated control cultured cardiomyocytes when viewed with the scanning electron microscope at low and high magnification (Figures 5(a) and 5(b)). After sonoporation with a low concentration of liposome (Figure 5(c)) and with a high concentration of liposome (Figure 5(d)), microdimples or pores were observed on the surfaces of the cultured cardiomyocytes. Figure 5 (a) and (b) Scanning electron microscopic images of intact cell surfaces of cultured cardiomyocytes. Scale dots are indicated on the images. (c) Image of a cell surface immediately after sonoporation using 1 × 106particles/mL liposome. … 4.