ABSTRACT
Objectives: This study aimed to objectively evaluate the water-jet-functioned electrosurgical knife injection performances in a desktop experiment. Methods: Five types of water-jet-functioned electrosurgical knives, including two injection styles of sheath-type (A: DualKnife J, KD-655L; B: FlushKnife, DK2620-J-B20S; C: Splash M-Knife, DN-D2718B; D: ISSEN, SN1650-20) and tip-type (E: ORISE ProKnife, M00519361) were evaluated. These knives were compared with an injection needle (Control: SuperGrip 25G) as a control. The injection speed under constant pressure and the injection efficiency for each knife against prepared porcine stomach mucosa were evaluated. The additional clear gel injections using an injection needle were observed using an indigo blue-colored gel to evaluate the difference between the locations of water-jet holes. Results: Four types of knives, except for A, showed significantly higher water-jet speeds (A: 0.79 ± 0.03 g/20 s, B: 2.56 ± 0.05 g/20 s, C: 3.09 ± 0.06 g/20 s, D: 2.86 ± 0.05 g/20 s, and E: 1.79 ± 0.03 g/20 s) compared to that of the control (1.21 ± 0.03 g/20 s). Meanwhile, significantly higher efficacy of injection was found in the tip-type water-jet function knife, second to the injection needle (Control: 37.2% ± 35.5%, A: 20.9% ± 20.2%, B: 1.1% ± 2.2%, C: 6.2% ± 12.6%, D: 12.5% ± 15.6%, and E: 33.3% ± 32.2%). An additional injection experiment revealed that the injection with a piercing tip into the gel could achieve sufficient additional injection inside the stacked clear gel. Conclusions: The tip-type water-jet function electrosurgical knife is preferable for effective submucosal injection during endoscopic treatments.
ABSTRACT
At present, the most reliable method for creating genetically modified chickens is the modification of the DNA sequence of primordial germ cells (PGCs). However, during embryogenesis, only a small number of chicken PGCs can be obtained. Therefore, in vitro PGC culturing is necessary to obtain sufficient cells for further genetic engineering. Previously reported PGC culturing methods lack versatility. We report here a new protocol for stable and efficient culturing of chicken PGCs using small-molecule inhibitors. The growth rate of PGCs was investigated following the addition of three small-molecule inhibitors, including blebbistatin, into the culture medium. Chicken PGC survival and proliferation rates increased after the addition of small-molecule inhibitors, compared with the untreated control. Blebbistatin was shown to be the most effective inducer of PGC growth. Long-term culturing of PGCs with blebbistatin maintained the morphology of typical PGCs, and these cells expressed marker proteins such as chicken vasa homolog (CVH) and NANOG. Additionally, PGCs transfected with a fluorescent protein gene were shown to migrate into the gonads of the recipient embryo, and progeny derived from PGCs cultured by this method were efficiently obtained. These results demonstrate that small-molecule inhibitors represent a useful tool for stable and efficient chicken PGC culturing.
