Arm movements during crawling locomotion of octopus sinensis

The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P6

Effective and Steady Differentiation of a Clonal Derivative of P19CL6 Embryonal Carcinoma Cell Line into Beating Cardiomyocytes

The P19CL6 cell line is a useful model to study cardiac differentiation in vitro. However, large variations were noticed in the differentiation rates among previous reports as well as our individual experiments. To overcome the unstable differentiation, we established P19CL6-A1, a new clonal derivative of P19CL6 that could differentiate into cardiomyocytes more efficiently and stably than the parent using the double stimulation with 5-Aza and DMSO based on the previous report. We also introduced a new software, Visorhythm, that can analyze the temporal variations in the beating rhythms and can chart correlograms displaying the oscillated rhythms. Using P19CL6-A1-derived cardiomyocytes and the software, we demonstrated that the correlograms could clearly display the enhancement of beating rates by cardiotonic reagents. These indicate that a combination of P19CL6-A1 and Visorhythm is a useful tool that can provide invaluable assistance in inotropic drug discovery, drug screening, and toxicity testing

Borrowable Fractional Ownership Types for Verification

Automated verification of functional correctness of imperative programs with references (a.k.a. pointers) is challenging because of reference aliasing. Ownership types have recently been applied to address this issue, but the existing approaches were limited in that they are effective only for a class of programs whose reference usage follows a certain style. To relax the limitation, we combine the approaches of ConSORT (based on fractional ownership) and RustHorn (based on borrowable ownership), two recent approaches to automated program verification based on ownership types, and propose the notion of borrowable fractional ownership types. We formalize a new type system based on the borrowable fractional ownership types and show how we can use it to automatically reduce the program verification problem for imperative programs with references to that for functional programs without references. We also show the soundness of our type system and the translation, and conduct experiments to confirm the effectiveness of our approach.Comment: An extended version of the paper to appear in Proceedings of VMCAI 202

Effect of nalfurafine hydrochloride on the basal pressure of the sphincter of Oddi in anesthetized rabbits

Background: Opioid analgesics, which are classified as μ-opioid receptor agonists, are known to induce spasms or contraction of the sphincter of Oddi (SO), thereby inducing or exacerbating biliary diseases such as biliary obstruction, gallbladder dysfunction, cholelithiasis, pancreatitis, biliary dyskinesia, cholangitis, and cholecystitis. However, effects of κ-opioid receptor agonists on SO contraction have not been clarified. In the present study, we investigated the effect of nalfurafine hydrochloride (nalfurafine), (E)-N-[17-(cyclopropylmethyl)-4,5α-epoxy-3,14-dihydroxymorphinan-6β-yl]-3-(furan-3-yl)-N-methylprop-2-enamide monohydrochloride, a selective κ-opioid receptor agonist, on spontaneous contraction of rabbit SO.Methods: SO contraction was measured using manometry in anesthetized rabbits. Rabbits were anesthetized with intravenous administration of 25 mg/kg sodium pentobarbital. An open tip catheter was inserted into the common bile duct toward the SO ampullae. Saline was perfused through the lumen of the open tip catheter at a constant rate of 6 ml/hr using a syringe pump. Nalfurafine, morphine, and pentazocine were intravenously (i.v.) administered and perfusion pressure was recorded.Results: Morphine (0.3 mg/kg, i.v.) and pentazocine (3 mg/kg, i.v.) were found to increase SO perfusion pressure, suggesting that these opioid analgesics may cause SO contraction. In contrast, nalfurafine (0.2 μg/kg, i.v.) decreased the perfusion pressure, indicating that this κ-opioid receptor agonist suppresses SO contraction.Conclusions: These findings suggest that nalfurafine is unlikely to induce or exacerbate biliary diseases and may be safely used in patients with these disorders