No abstract

Ultrasound (US)-mediated gene delivery (UMGD) of nonviral vectors was demonstrated in this study to be an effective method to transfer genes into the livers of large animals via a minimally invasive approach. We developed a transhepatic venous nonviral gene delivery protocol in combination with transcutaneous, therapeutic US (tUS) to facilitate significant gene transfer in pig livers. A balloon catheter was inserted into the pig hepatic veins of the target liver lobes via jugular vein access under fluoroscopic guidance. tUS exposure was continuously applied to the lobe with simultaneous infusion of pGL4 plasmid (encoding a luciferase reporter gene) and microbubbles. tUS was delivered via an unfocused, two-element disc transducer (H105) or a novel focused, single-element transducer (H114). We found applying transcutaneous US using H114 and H105 with longer pulses and reduced acoustic pressures resulted in an over 100-fold increase in luciferase activity relative to untreated lobes. We also showed effective UMGD by achieving focal regions of >10 5 relative light units (RLUs)/mg protein with minimal tissue damage, demonstrating the feasibility for clinical translation of this technique to treat patients with genetic diseases.

The influence of different secondary cooling conditions (air cooling and water cooling) on microstructure, texture and properties of Fe-1.2wt%Si non-oriented silicon strips prepared by twin-roll strip casting were studied. Specimens were examined by OIM, EBSD and X-RD. The microstructures obtained by water cooling are more homogeneous and coarse in grain size than that obtained by air cooling. The dominant {100} texture can be observed in the case of water cooled, while the air cooled strip show a diffuse texture characteristic. The annealed sheets subjected to water cooling than air cooling show higher permeability and lower core loss due to the presence of relatively larger grain size and more ideal fibre components such as Goss and Cube., It seems that rapid secondary cooling of as cast strips can furtherer optimize the microstructure and texture prior to cold rolling and then substantially the final magnetic properties of 1.2wt% Si non-oriented silicon steels.