Search

Aims/Introduction Insomnia is associated with type 2 diabetes mellitus, and results in a low quality of life. There are several known relationships between insomnia and personality. Thus, we clarified the association between some personality traits and insomnia among Japanese type 2 diabetes mellitus patients. Materials and Methods The participants were 504 type 2 diabetes mellitus patients (mean age 63.9 ± 12.5 years). Sleep disturbance and personality traits were evaluated using the Pittsburgh Sleep Quality Index‐Japanese version and the Ten‐Item Personality Inventory Japanese version, respectively. Lifestyle factors, glycated hemoglobin levels and depressive status of the patients were also included in the analyses. Results Among the 504 participants with type 2 diabetes mellitus, 154 (30.6%) showed probable insomnia. After adjustment for confounders, being female, living alone, high body mass index and “high neuroticism” were found to be significantly correlated with current insomnia. No other relationships between insomnia and glycated hemoglobin or lifestyle factors, such as smoking, drinking alcohol or exercise frequency, were found. Conclusions The prevalence of insomnia in individuals with type 2 diabetes mellitus was high, and the risk factors included some personality factors. Future prospective studies are required to confirm the therapeutic effects of behavioral interventions for insomnia in patients with type 2 diabetes mellitus.

Aims/Introduction: We studied the mechanisms for the possible insulinotropic action of apolipoprotein (Apo) A-I in mouse insulinoma (MIN6) cells. Materials and Methods: The effects of ApoA-I on cAMP production and glucose-stimulated insulin secretion (GSIS), and the dose dependency (ApoA-I at 5, 10, 25, and 50 μg/ml) were determined using MIN6 cells. The effects of the small-interference ribonucleic acid (siRNA) of ATP-binding cassette transporter A1(ABCA1) and Cell division control protein 42 homolog (Cdc42) on the insulinotropic action of ApoA-I was studied, as well as mRNA and protein levels of ABCA1 and Cdc42. Then, the influence of cAMP inhibitor SQ22536, and the cAMP-dependent protein kinase inhibitor Rp-cAMPS on ApoA-I action were studied. Results: Addition of ApoA-I produced cAMP and increased insulin secretion, dose-dependently in high glucose concentration (25 mmmol/l). and ABCA1 protein and Cdc42 mRNA and protein were also enhanced. Specific ABCA1 and Cdc42 siRNA significantly decreased the effects of ApoA-I on insulin secretion compared with negative controls. Manifestations of ABCA1 and Cdc42 mRNA and protein were less than that of the negative control group. Both cAMP inhibiror (SQ22536) and protein kinases inhibitor (Rp-cAMPS) strongly inhibited the effects of ApoA-I on insulin secretion. Conclusions: We demonstrated that ApoA-I enhances glucose-stimulated insulin release in high glucose at least partially through the ABCA1/Cdc42/cAMP/ Protein kinase A (PKA) pathway.

Aims Cholesterol efflux with high-density lipoprotein (HDL) particles has an important role in the first step of reverse cholesterol transport (RCT). However, HDL function in type 2 diabetes has not been well investigated thoroughly. We measured cholesterol efflux in 36 patients with type 2 diabetes compared with 9 controls without diabetes. Methods The HDL fraction was separated with polyacrylamide gel and recovered using the protein recovery system. Concentration adjusted HDL fraction was used to determine HDL-mediated cholesterol efflux (Efflux-hdl) from THP-1 derived macrophages. We measured paraoxonase-1 (PON 1) activity to determine antioxidation capacity, serum amyloid A protein (SAA) to determine inflammatory response, and carboxymethyl-lysin (CML) to determine antiglucoxidative capacity. Results Efflux-hdl demonstrated no correlation with plasma apoprotein A-1 (ApoA-I) or HDL-cholesterol in patients with diabetes. PON1 activity in the patients’ HDL fraction was positively correlated with Efflux-hdl (r = 0.39, p = 0.02), and showed a negative tendency with HbA1c levels (r = −0.28, p = 0.10). SAA and CML levels did not demonstrate correlation with Efflux-hdl in patients with diabetes. Conclusion We confirmed the functional changes in HDL particles in the patients. Efflux-hdl from macrophages was reduced depending upon the decrease in PON1 activity, which was inversely related to HbA1c levels.

Anodization of single-crystalline silicon was carried out under microwave plasma created by electron cyclotron resonance (ECR), and the anodization characteristic and oxide film property were evaluated. The growth rate of the oxide film depended strongly on the oxygen pressure and the growth rate reached the maximum under relatively high oxygen pressure. Since the plasma parameters and substrate temperature were dependent on the oxygen pressure, the oxidation was thought to be dependent on the supply of oxygen atoms from plasma and the generation of silicon atoms and dangling bonds at the Si-oxide interface. The X-ray photoelectron spectra revealed the formation of stoichiometric SiO2. This result provided insight into the oxide growth process. In addition, the electric conduction in an MOS device formed using this oxide was investigated. As a result, it was found that the dc high field conduction prior to the self-healing breakdown was based on the tunneling of electrons injected by Schottky emission through the oxide. Also, the negative resistance observed after the self-healing breakdown was caused by the formation of space charges caused by the impurity ions.

This paper describes the plasma anodization of aluminum thin films in microwave‐discharge oxygen plasma with electron‐cyclotron‐resonance conditions from the following two points of view. First, the change in the current efficiency with the anodizing conditions and the factors affecting the oxide growth are examined. The current efficiency depends on the microwave input power, the magnetic field, the distance between the specimen and the location where the plasma is generated, the pressure of oxygen gas, and the presence of ozone. Second, some considerations are given on the generation of the atomic oxygen that closely relates to the growth of the oxide film. The generation process was calculated with a simple model and an approximation. The result suggests that atomic oxygen is generated when electrons and positive ions are extinguished by dissociative recombination in the course of ambipolar diffusion in the plasma. In addition, on the supposition that only the rate of atomic oxygen supplied to the surface of the specimen limits the growth rate of the oxide film, the minimum density of atomic oxygen necessary for the oxide growth was estimated. It was found to be maximal under the appropriate conditions of oxygen gas pressure and position of the specimen. However, the atomic oxygen density is also a complicated function of other conditions such as the electron density, the molecular oxygen density, and the electron energy.

In plasma anodization the oxide growth rate decreases with time during constant current anodization. This phenomenon has been studied noting that the surface potential of specimens is closely related to the current efficiency. The oxide growth rate during the plasma anodization of aluminum wires or films is observed to vary depending on the dimensions of specimens and also on the thickness of a wet‐anodic Al2O3 film previously grown on the specimen surface. It turns out that the surface potential changes not only because the plasma‐anodic Al2O3 film itself is not uniform in thickness but also because the surface potential of the oxide film is floating in a plasma. The change of the surface potential was observed using a sounding probe. It is concluded that a difference in the surface potential exists between the central part and the peripheral part of the specimen, and that the difference increases with the increase of the forming voltage. The change of the surface potential may be the cause of the rate‐l...

The enhancement of the growth rate of Al2O3 has been observed during plasma anodization accompanied by optical excitation with low‐power visible argon‐ion laser light. The increase of the current efficiency with light is approximately 20% of the efficiency without it. This enhancement of the oxide growth rate is considered to arise from promoting the generation rate of atomic oxygen, which contributes to the anodization as oxidizing species, in the plasma sheath near the specimen and/or on the specimen surface irradiated by the laser light. Although most of the atomic oxygen is regarded to be generated by the dissociation of molecular oxygens colliding with plasma electrons, the laser excitation might help the cumulative dissociation of molecular oxygens.

The enhancement of the growth rate of Al2O3 has been observed during plasma anodization accompanied by optical excitation with low-power visible argon-ion laser light. The increase of the current efficiency with the laser light is approximately 20% of that without. And this enhancement of the oxide growth rate is considered to arise from promoting the generation rate of atomic oxygens, which contribute to the anodization as oxidizing species, in the plasma sheath near the specimen and/or on the specimen surface irradiated by the laser light. Although most of atomic oxygens are regarded to be generated by the dissociation of molecular oxygens colliding with plasma electrons, the laser excitation might help the cumulative dissociation of molecular oxygens.

The behavior of the species of oxidation dominating the oxide growth in plasma anodization of Al is investigated in this paper. The relationship between the current efficiency and the plasma parameters was observed under the different anodizing conditions with changing the construction of the discharge electrodes and the discharge current in order to clarify the factors contributing to the anodization. The formula of the current efficiency was tentatively derived from a rough model of the growth process of the oxide film with an approximation. The formula, in practice, was consistent with the experimental results. Consequently, it was suggested that the rate‐limiting step in the oxide growth is due to the supply of the atomic oxygens from the plasma to the surface of the specimen and also to their ionization.

By analysis of the current-voltage characteristics of Al-plasma-anodized Al 2 O 3 -plasma systems the high field conduction characteristics of plasma-anodized thin Al 2 O 3 films in the plasma were found to be expressed by the equation J s = J f0 exp(BF) (where J s is the specimen current density, F the electric field strength across the oxide film and J f0 and B are constants); in this experiment B and J f0 were (1.1-1.4)×10 -6 cm V -1 and about 10 -8 A cm -2 respectively. It was ascertained that the current efficiency in the plasma anodization of aluminium becomes a maximum when the surface potential of the specimen is equal to the plasma space potential. From this it was deduced that most of the negative oxygen ions contributing to plasma anodization are generated by the ionization of oxygen atoms adsorbed on the surface of the specimen.