- 著者
- Yu Fukuoka El-Sayed Khafagy Takahiro Goto Noriyasu Kamei Kozo Takayama Nicholas A. Peppas Mariko Takeda-Morishita
- 出版者
- The Pharmaceutical Society of Japan
- 雑誌
- Biological and Pharmaceutical Bulletin (ISSN:09186158)
- 巻号頁・発行日
- vol.41, no.5, pp.811-814, 2018-05-01 (Released:2018-05-01)
- 参考文献数
- 14
- 被引用文献数
- 24
In previous studies we showed that the complexation hydrogels based in poly(methacrylic acid-g-ethylene glycol) [P(MAA-g-EG)] rapidly release insulin in the intestine owing to their pH-dependent complexation properties; they also exhibit a high insulin-loading efficiency, enzyme-inhibiting properties, and mucoadhesive characteristics. Cell-penetrating peptides (CPPs), such as oligoarginines [hexa-arginine (R6), comprising six arginine residues], have been employed as useful tools for the oral delivery of therapeutic macromolecules. The aim of our study was to investigate the combination strategy of using P(MAA-g-EG) hydrogels with R6-based CPPs to improve the intestinal absorption of insulin. A high efficiency of loading into crosslinked P(MAA-g-EG) hydrogels was observed for insulin (96.1±1.4%) and R6 (46.6±3.8%). In addition, immediate release of the loaded insulin and R6 from these hydrogels was observed at pH 7.4 (80% was released in approximately 30 min). Consequently, a strong hypoglycemic response was observed (approximately 18% reduction in blood glucose levels) accompanied by an improvement in insulin absorption after the co-administration of insulin-loaded particles (ILP) and R6-loaded particles (ALP) into closed rat ileal segments compared with that after ILP administration alone. These results indicate that the combination of P(MAA-g-EG) hydrogels with CPPs may be a promising strategy for the oral delivery of various insulin preparations as an alternative to conventional parenteral routes.
- 著者
- Takahiro Goto Yasuhiro Sugimoto Daisuke Nakanishi Keisuke Naniwa Koichi Osuka
- 出版者
- The Institute of Electronics, Information and Communication Engineers
- 雑誌
- Nonlinear Theory and Its Applications, IEICE (ISSN:21854106)
- 巻号頁・発行日
- vol.13, no.4, pp.598-614, 2022 (Released:2022-10-01)
- 参考文献数
- 23
- 被引用文献数
- 1
This study focused on the bifurcation of coordination relationships between McKibben pneumatic actuators (MPA). We aimed to arrive at the control theory of a robot with MPAs by analyzing this bifurcation phenomena. The control law using the MPA tension generates multiple motion modes, and the coordination relationships between MPAs bifurcate depending on parameters reported in a previous study. The bifurcation phenomenon between two of those coordination relationships was analyzed and it was found that despite a similar link movement, the phase oscillators exhibited different coupled modes. The important difference between two coupled modes was determined to be the relationship between the MPA pressure and length. Further, we verified that the angular velocity of the link was the parameter that generated this phenomenon by analyzing it in correspondence with the model of forced oscillation. In addition, we confirmed the bifurcation phenomenon employing a 1-DOF pendulum machine.