This study examined the effects of the time-length of intermittent insertions of a standing posture on the subjective fatigue and lower-leg swelling in continuous deskwork. The subjects were required to do a computer task for 120 min under the following conditions: 1) Two-times repetition of 10-min standing - 50-min sitting, 2) Two-times repetition of 40-min standing - 20- min sitting, 3) 120-min continuous sitting. Lower-leg swelling, subjective fatigue and task-performance were recorded. The results revealed that the condition with the insertions of 10-min standing showed lessening of swelling of the lower leg and reduction of the strain of the buttocks and the low back compared to the continuous sitting. In the condition with the insertion of 40-min standing, fatigue of the feet and swelling of the lower leg were prominent. Taking into account these results and the results of previous studies, the duration of 10 to 30 minutes is suggested as an appropriate time range for inserting a standing position in deskwork considering the short-term effects on the strain to low-back and the lower feet.
An infant disorder, so-called meningitis in infancy (SCMI), was reported by Sukehiko Itoh et al. in the 28th year of the Meiji Era (1895) in Japan. Twenty-eight years later, Ikutaro Hirai, a professor at the Kyoto University, reported in the 12th year of the Taisho Era (1923) that SCMI was a chronic lead-poisoning disease caused by white lead included in the mothers’ cosmetic powder. Then, a ministerial ordinance about regulation of white lead was declared in the 5th year of the Showa Era (1930) and implemented in the 10th year of the Showa Era (1935). In this review, we have provided a sketch of SCMI researches during this period from the perspective of experimental studies. There were 19 publications including four original articles, nine presentations, three proceedings and three Japanese abstracts. We summarized the four original articles here. (1) Suma suggested that sodium thiosulfate would be an effective medi cine for lead-poisoning disease based on his clinical experiences and animal experiments. (2) Tatsumi found no significant difference in the transfer of fuchsine from blood to cerebral spinal fluid between control and lead-poisoned rabbits, (3) Yasu reported that several factors (age, type of the bones) were related to lead concentrations in the bones of the animals affected by experimental lead poisoning, (4) Yasu also reported that different routes of lead administration (oral ingestion or subcutaneous injection) caused differential lead concentrations in the blood and liver of the lead-poisoned animals. The findings of the two studies reported by Yasu are still valuable now.