堀 秀生

Abstract Introduction Indoxyl sulfate (IS) is a protein‐bound uremic toxin that causes uremic sarcopenia. IS has poor dialysis clearance; however, the addition of a binding competitor improves its removal efficiency. Methods Dialysis experiments were performed using N‐acetyl‐l‐tryptophan (L‐NAT) instead of l‐tryptophan (Trp) using pooled sera obtained from dialysis patients. The molecular structures of L‐NAT and Trp were similar to that of IS. Therefore, we examined whether Trp and L‐NAT were involved in muscle atrophy in the same manner as IS by performing culture experiments using a human myotube cell line. Results The removal efficiency of L‐NAT was the same as that of Trp. However, L‐NAT concentrations in the pooled sera increased at the end of the experiment. Trp (1 mM) decreased the area of human myocytes, similar to IS, whereas L‐NAT did not. Conclusion L‐NAT is a binding competitor with the ability to remove protein‐bound IS while preventing sarcopenia.

It has been a strong tendency to use information communication technology (ICT) to construct various education/training systems to help students or other learners to master necessary skills more easily, among which such systems with operational practice are particularly welcome in addition to the conventional e-learning ones mainly for obtaining textbook-like knowledge. In this study, we propose a medical training system for the operation of heart-lung machine. Two training contents, i.e., one for the basic operations and another for troubleshooting, are considered in the system.