Regional Variations of Insulin Secretion and Insulin Sensitivity in Japanese Participants With Normal Glucose Tolerance.

Purpose: Regional differences in dietary patterns in Asian countries might affect the balance of insulin response and sensitivity. However, this notion is yet to be validated. To clarify the regional differences in the insulin response and sensitivity and their relationship to nutrients, we compared the insulin secretory response during an oral glucose tolerance test in Japanese participants. Methods: This observational retrospective cohort study analyzed the data from participants with normal glucose tolerance (NGT) from four distinct areas of Japan with regard to the food environment: Fukushima, Nagano, Tokushima, and Okinawa based on data available in the Japanese National Health Insurance database. Results: Although the glucose levels were comparable among the four regions, the insulin responses were significantly different among the regions. This difference was observed even within the same BMI category. The plot between the insulin sensitivity index (Matsuda index) and insulinAUC/glucoseAUC or the insulinogenic index showed hyperbolic relationships with variations in regions. The indices of insulin secretion correlated positively with fat intake and negatively with the intake of fish, carbohydrate calories, and dietary fiber. Conclusions: We found that significant regional differences in insulin response and insulin sensitivity in Japanese participants and that nutritional factors may be linked to these differences independently of body size/adiposity. Insulin response and insulin sensitivity can vary among adult individuals, even within the same race and the same country, and are likely affected by environmental/lifestyle factors as well as genetic traits.

A new flexible piezoelectric pressure sensor array for the noninvasive detection of laryngeal movement during swallowing.

We tried to develop a new device to detect laryngeal movement noninvasively. We made small piezo pressure sensors (length, 1.5 mm, width, 7.0 mm), and five of these were lined up with 3.0-mm intervals and embedded in the middle of a palm-sized urethane resin sheet. This sheet was lightly attached to the ventral surface of the neck near the laryngeal prominence. The first and second peaks obtained from each sensor should correspond to the period when the larynx moves to the upper and lower positions during swallowing. The mean maximum rising velocities for men and women were about 0.08 and 0.11 m/s, respectively. Similarly, the mean maximum lowering velocities for men and women were about 0.09 and 0.11 m/s, respectively. The swallowing latencies for men and women were about 0.49 and 0.53 s, respectively. In conclusion, we succeeded in developing a new device, which will be useful in evaluating the swallowing function.

Subclinical Carotid Atherosclerosis Burden in the Japanese: Comparison between Okinawa and Nagano Residents.

AIM: The prevalence of overweight and a change in atherosclerotic lipid profiles may be linked to region-specific differences in atherosclerotic diseases. We evaluated whether the lipid phenotype could be linked to region- and sex-specific differences in the degree of atherosclerosis. METHODS: Non-diabetic subjects included Okinawa (n=1674) and Nagano (n=1392) residents aged 30-75 years who underwent carotid ultrasonography for the measurement of maximum intima-media thickness (max IMT). RESULTS: Average max IMT was higher in Okinawa men and women, and the increase in max IMT with age was enhanced in men. Multiple regression analysis showed that in addition to age and systolic blood pressure, low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol were IMT determinants only in men for both Okinawa and Nagano. Meanwhile, HDL-cholesterol was a determinant for Okinawa men and women, but not for Nagano men and women. CONCLUSIONS: This is the first report to show region- and sex-specific differences in the determinants for max IMT in a Japanese population. The evaluation of the relationship between lipid profile patterns and region- and sex-specific differences in carotid atherosclerosis burden may be required.