Relationship between the floating toe and the center-of-pressure position in an upright posture among students.

[Purpose] The incidence of floating toes in children is increasing. Although the anteroposterior center of pressure in children is present posteriorly, its relationship with the floating toe is unclear. This study aimed to clarify the relationship between the position of the anteroposterior center of pressure and the floating toe in an upright posture in children. [Participants and Methods] In this cross-sectional study, a Win-Pod (Medicapteurs) platform was used to measure the position of the anteroposterior center of pressure in 208 boys and 195 girls from Japanese elementary schools. Using images of the plantar footprint, floating toes were assessed and the floating toe score was calculated. [Results] The anteroposterior center of pressure position was situated 32.3 ± 8.2% from the heel. The floating toe score of all the participants was 3.5 ± 2.4, with a very high rate of 98%. The floating toe score had a significant, moderate correlation with age, height, weight, and the anteroposterior center-of-pressure position. Multivariate analysis revealed an association between the floating toe score and the anteroposterior center-of-pressure position, height, and weight. [Conclusion] There is significant relationship between the anteroposterior center-of-pressure position and the floating toe score in an upright posture in Japanese elementary school students.

Molecular design of potent, hydrophilic tyrosinase inhibitors based on the natural dihydrooxyresveratrol skeleton.

In this study, dihydrooxyresveratrol glucosides 3-6 were synthesized for the first time to the best of our knowledge by the Wittig reaction and Schmidt glycosylation as key steps for the purpose of developing novel hydrophilic tyrosinase inhibitors. Results obtained from inhibitory studies revealed 50% inhibitory concentration (IC50) values of 12.80 µM and 2.63 µM for 4-resorcinol glucosides 3 and 4, respectively. The IC50 value of 4 was approximately 4 times greater than that of kojic acid, which is a typical tyrosinase inhibitor. In contrast, 5-resorcinol glucosides 5 and 6 exhibited tyrosinase-inhibitory activity; however their IC50s were not estimated within 100 µM. These results suggested that the discovering 4-resorcinol structure of dihydrooxyresveratrol glucoside is crucial for inducing potent tyrosinase-inhibitory activity.