Analysis of head motions during food intake in Japanese adults using a new motion capture system.

OBJECTIVE: A new motion capture system was developed to verify the hypothesis that "during food intake, head motion changes according to the properties of the food." DESIGN: Twenty healthy males and 20 healthy females with right-handed and normal occlusion participated in this study. The motion capture system used consisted of a Microsoft Xbox One Kinect Sensor® and a newly-developed program. Meatballs (solid), yogurt (paste), and water (fluid) were used as food samples. Head motion distance, head turning angle, and head forward angle were measured during food intake. Unpaired t-tests were used to analyze each head motion and compare the sexes. A one-way repeated measures analysis of variance was used to analyze each head motion for different food samples. RESULTS: Head motion distance was significantly smaller in females for the meatball and yogurt, but not for water. There were no significant differences between the sexes for head turning angle or head forward angle. Head motion distance and head forward angle were significantly larger for water than for meatballs and yogurt. The head turning angle was significantly smaller for the meatball than for yogurt and water. CONCLUSIONS: The results indicated that females tend to consume food without moving their heads when eating solid and paste foods. As the fluidity of the food increased, the head moved in a turning motion to avoid spilling the food, and the heads tilted forward. The motion capture system used in this study was also effective in analyzing head motion during eating.

A Qualitative Study on the Development of Professionalism Among Japanese Dental Students.

BACKGROUND: Professionalism is believed to vary depending on factors such as era and culture. Therefore, clarifying the meaning of professionalism in each country, region, and workplace is essential. However, how professionalism is cultivated among dental students in Japanese schools has yet to be fully elucidated. Therefore, this study examined whether professionalism among Japanese dental students changes by year. This research will contribute to effective professional education. PARTICIPANTS AND METHODS: The participants included six fourth-year dental students and nine fifth-year dental students. Semi-structured interviews were conducted from November 2018 to January 2019, and verbatim transcripts were created from the recorded data. Based on these verbatim transcripts, thematic analysis was utilized to examine and identify professionalism components for each academic year. RESULTS: Three themes based on 14 constituent concepts were obtained for fourth-year students. Three themes based on 20 constituent concepts were obtained for fifth-year students. Fourth-year students primarily focused on technical aspects. In contrast, fifth-year students placed greater emphasis on attitude and communication skills. CONCLUSION: From fourth-year students, who primarily focus on classroom learning and practical training, to fifth-year students who gain clinical experience, the constituent elements of professionalism became more complex. However, this study did not examine other aspects of healthcare professionalism, such as interprofessional collaboration. A comprehensive education program tailored to the clinical setting is necessary for cultivating professionalism.

Comparison of mouth rinsing performance between adults and children using a contactless vital sensing camera.

BACKGROUND: Evaluating mouth rinsing skills is useful for assessing oral function, however current evaluation methods are subjective. OBJECTIVES: This study compared mouth rinsing between adults and children using a contactless camera to capture lip motion. METHODS: The subjects comprised 16 adults and 13 children with no oral dysfunction. A compact vital sensing camera adapted from a Microsoft Xbox One Kinect Sensor® (Kinect) was placed 100 cm from the floor and 120 cm from the subject; 5, 10 and 15 ml of water were used as samples. Participants were instructed to hold the sample in the oral cavity, close the lips and move the sample alternatively left and right for 15 s. Maximum/minimum displacement from the reference plane and rinsing cycle for each sample were analysed by one-way analysis of variance. RESULTS: In adults, there was no significant difference in the maximum/minimum displacement between the left and right sides of the angulus oris due to differences in sample amount. In children, the right maximum significantly differed between the 5- and 15-ml and 10- and 15-ml samples, while the left maximum significantly differed between the 5- and 10-ml and 5- and 15-ml samples. The right minimum significantly differed between the 5- and 10-ml samples, as did the duration of mouth rinsing between the 5- and 15-ml samples. CONCLUSIONS: In children, lip movement and mouth rinsing duration tended to decrease with increasing sample volume. Evaluating lip movement using a contactless vital sensing camera is useful for assessing children's development of oral function.

Relationship between lip motion detected with a compact 3D camera and swallowing dynamics during bolus flow swallowing in Japanese elderly men.

Clinical application of a swallowing function evaluation system that is minimally invasive and enables an objective evaluation is necessary. We constructed a system that can synchronise and analyse lip motion with a three-dimensional (3D) camera and swallowing dynamics with videofluoroscopy (VF) and clarified the relationship between lip movement and swallowing dynamics. A compact 3D camera was adapted to Microsoft XBox One Kinect Sensor® . We examined Kinect's accuracy and repeatability and analysed the highest measurement accuracy and repeatability of the distance between anguli oris muscles. The constructed system simultaneously measured, synchronised and analysed lip motion by Kinect and swallowing dynamics by VF. Fourteen elderly men without dysphagia were included. Barium turbid solution (5, 10, 15 and 20 mL) was used for swallowing. Measurement parameters were the 3D distance between angulus oris displacement (TDDD), swallowing quantity (SQ), oral transit time (OTT), stage transit duration (STD), pharyngeal transit time (PTT) and total swallowing duration (TSD). Statistical analyses were performed. The measurement accuracy and reproducibility were optimum within a 10° horizontal imaging angle at a 120-cm measurement distance. SQ, TDDD, OTT, STD, PTT and TSD showed significant differences, and correlation was found between TDDD and OTT. SQ affected TDDD, OTT, STD, PTT and TSD; OTT could be predicted from TDDD. Improvement in the system and analysis method was considered to enable prediction of swallowing dynamics from body surface movement of the head and neck, including realisation of measurement conditions with higher precision and reproducibility, and from lip motion.

Snail modulates cell metabolism in MDCK cells.

Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP(+)-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of key enzymes. This results in enhanced glucose dependency and leads to cell death under low-glucose conditions. On the other hand, the reduced requirements for oxygen and nutrients from the surrounding environment, might confer the resistance to cell death induced by hypoxia and malnutrition.