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Aims/Introduction An efficient screening strategy for identification of cognitive dysfunction remains a clinical issue in the management of elderly adults with diabetes. A magnetic resonance imaging voxel‐based specific regional analysis system for Alzheimer’s disease (VSRAD) has been developed as an automated brain morphometry system that includes the hippocampus. We carried out a multicenter retrospective study to evaluate the utility of VSRAD for screening cognitive dysfunction in diabetes outpatient clinics. Materials and Methods We enrolled patients with diabetes aged >65 years who underwent brain magnetic resonance imaging scans for the purpose of a medical checkup between November 2018 and May 2019. Patients who were already suspected or diagnosed with mild cognitive impairment and/or dementia as well as those with a history of cerebrovascular disease were excluded. Results A total of 67 patients were enrolled. Five patients were diagnosed with mild cognitive impairment or dementia (clinical cognitive dysfunction). Patients with clinical cognitive dysfunction showed a significantly higher z‐score in VSRAD analysis (2.57 ± 0.47 vs 1.15 ± 0.55, P, We evaluated the utility of the voxel‐based specific regional analysis system of Alzheimer's disease, an automated brain morphometry system that includes the hippocampus, for screening unrecognized cognitive dysfunction in elderly patients with diabetes. This is the first report to assess the association between hippocampal atrophy and cognitive dysfunction by an automated voxel‐based morphometry system in clinical diabetes practice. The results suggest that the voxel‐based specific regional analysis system of Alzheimer's disease can be useful for early identification of cognitive dysfunction in the elderly with diabetes.

In this study, it is discussed how the cutting conditions for drilling deep holes in austenite stainless steel affect the machining accuracy of the hole straightness and the cutting temperature rise. As a result, it is possible to reduce the thrust force and make the machining time short by the combination of the step-feed amount and the feed rate. By changing the drill in incremental step from short drill length to long drill length, the straightness was improved. It was also found that the temperature rise of the drill was around 10 K regardless of the cutting speed when the small step-feed amount of 10 μm was given.

The effect of an imperfect interface on the dispersive behavior of in-plane time-harmonic symmetric waves in a pre-stressed incompressible symmetric layered composite, was analyzed recently by Leungvichcharoen and Wijeyewickrema (2003) . In the present paper the corresponding case for time harmonic anti-symmetric waves is considered. The bi-material composite consists of incompressible isotropic elastic materials. The imperfect interface is simulated by a shear-spring type resistance model, which can also accommodate the extreme cases of perfectly bonded and fully slipping interfaces. The dispersion relation is obtained by formulating the incremental boundary-value problem and using the propagator matrix technique. The dispersion relations for anti-symmetric and symmetric waves differ from each other only through the elements of the propagator matrix associated with the inner layer. The behavior of the dispersion curves for anti-symmetric waves is for the most part similar to that of symmetric waves at the low and high wavenumber limits. At the low wavenumber limit, depending on the pre-stress for perfectly bonded and imperfect interface cases, a finite phase speed may exist only for the fundamental mode while other higher modes have an infinite phase speed. However, for a fully slipping interface in the low wavenumber region it may be possible for both the fundamental mode and the next lowest mode to have finite phase speeds. For the higher modes which have infinite phase speeds in the low wavenumber region an expression to determine the cut-off frequencies is obtained. At the high wavenumber limit, the phase speeds of the fundamental mode and the higher modes tend to the phase speeds of the surface wave or the interfacial wave or the limiting phase speed of the composite. The bifurcation equation obtained from the dispersion relation yields neutral curves that separate the stable and unstable regions associated with the fundamental mode or the next lowest mode. Numerical examples of dispersion curves are presented, where when the material has to be prescribed either Mooney–Rivlin material or Varga material is assumed. The effect of imperfect interfaces on anti-symmetric waves is clearly evident in the numerical results.

To investigate the role of the β-cell in the occurrence of diabetes in obesity, longitudinal changes of insulingene expression and pancreatic insulin content were compared among genetically obese diabetic (Wistar fatty) rats, genetically obese nondiabetic (Zucker fatty) rats, and ventromedial hypothalamus (VMH)-lesioned obese rats. Plasma glucose levels were significantly elevated with age in Wistar fatty rats, whereas they were virtually unchanged in VMH-lesioned and Zucker fatty rats. Obesity and hyperinsulinemia were evident in VMH-lesioned rats 1 wk after the operation and in Zucker and Wistar fatty rats at 5 wk of age. In VMHlesioned rats, the pancreatic preproinsulin I mRNA (pplmRNA) level and pancreatic insulin content markedly increased approximately two- to threefold (P < 0.001) with the development of hyperinsulinemia, whereas sham-operated rats showed no significant change. In Zucker and Wistar lean rats, the pplmRNA level and pancreatic insulin content increased with age, corresponding to increases in body weight. In Zucker fatty rats, the pplmRNA level and pancreatic insulin content at 5 and 14 wk of age were significantly higher than those of lean littermates. The pplmRNA level in Zucker fatty rats at 14 wk of age reached 290% of that of their lean littermates (P < 0.001). On the other hand, the pplmRNA level and pancreatic insulin content in Wistar fatty rats at 5 and 14 wk of age did not increase more than those of their lean littermates at the corresponding ages and were therefore significantly lower than in Zucker fatty rats, which had a higher grade of hyperinsulinemia at 14 wk of age. The pplmRNA level in Wistar fatty rats at 14 wk of age was found to be 41% of that of Zucker fatty rats at corresponding age (P < 0.001). Increased pplmRNA level in association with hyperinsulinemia in VMHlesioned and Zucker fatty rats suggests that the activation of insulin-gene expression for adaptation to a large demand for insulin is common to obesity without diabetes (both experimental and genetic). Furthermore, the inability to augment pplmRNA level to meet a large demand for insulin in Wistar fatty rats is associated with the occurrence of diabetes. These findings suggest that obesity induces diabetes only when a primary defect exists in the β-cell.

The effects of four different diets, a balanced (BD), a high protein (HP), a high fat (HF), and a high carbohydrate (HC) diet on glucose tolerance and pancreatic hormone secretion were compared during the ten-week period immediately after weaning in rats having glucose intolerance induced by streptozocin in the neonatal period (NSZ). Feeding HF or HC produced a decrease in calorie intake and a delay in body weight increase. All NSZ rats showed glucose intolerance as adults; the HF rats showed a further deterioration of glucose tolerance and a decreased insulinogenic index after oral glucose loading. Plasma insulin levels of HC rats were lowest. The glucose-induced insulin and somatostatin secretion from the isolated perfused pancreas was almost identical in all four groups. The arginine-induced insulin and glucagon secretion was decreased in HF and HC rats, compared to both HP and BD rats, but somatostatin secretion was not. These results indicate that a high fat or high carbohydrate dietary environment is an important factor in the development of glucose intolerance and in the impairment of pancreatic hormone responsiveness to stimulation.

In order to determine the role of insulin and glucose transporter gene expression in the development of diabetes in obesity, we examined insulin and GLUT2-liver type and GLUT4-muscle-fat type glucose transporter mRNA levels in obese and diabetic rats. Ventromedial hypothalamus-lesioned (VMH), Zucker fatty (ZF), and Wistar fatty (WF) rats were used as models. VMH and ZF rats are most frequently used as models for simple obesity. In contrast, WF rats, which have been established by transferring the fa gene of ZF rats to Wistar Kyoto rats, develop both obesity and diabetes. Pancreatic insulin content of VMH rats at 10 weeks after the operation and of ZF rats at 5 and 14 weeks of age was significantly higher than that of controls. On the other hand, insulin content of WF rats at 5 and 14 weeks of age was not significantly different from that of lean littermates. The insulin mRNA levels of VMH rats were increased progressively and were significantly higher than those in sham-operated animals at 4 and 10 weeks after the operation. In ZF rats, the insulin mRNA levels at 5 and 14 weeks of age were significantly higher than those of their lean littermates. In WF rats, by contrast, the insulin mRNA levels were similar to those of lean littermates at 5 and 14 weeks of age. The insulin mRNA levels of WF rats were about 40% of that of ZF rats at 14 weeks of age. On the other hand, at 14 weeks of age, the GLUT2 mRNA levels of liver were significantly higher in ZF and WF rats than those in their respective littermates, but not at 5 weeks of age. The GLUT4 mRNA levels of skeletal muscle in both ZF and WF rats were not significantly different from those of controls. It is suggested that the inability of WF rats to augment insulin gene expression in response to a large demand for insulin is associated with the occurrence of diabetes, and that the activation of GLUT2 mRNA without the activation of GLUT4 mRNA is common to obesity with and without diabetes.