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Abstract: Aim: Lactate is produced in and released from skeletal muscle cells. Lactate receptor, G‐protein‐coupled receptor 81 (GPR81), is expressed in skeletal muscle cells. However, a physiological role of extracellular lactate on skeletal muscle is not fully clarified. The purpose of this study was to investigate extracellular lactate‐associated morphological changes and intracellular signals in C2C12 skeletal muscle cells. Methods: Mouse myoblast C2C12 cells were differentiated for 5 days to form myotubes. Sodium lactate (lactate) or GPR81 agonist, 3,5‐dihydroxybenzoic acid (3,5‐DHBA), was administered to the differentiation medium. Results: Lactate administration increased the diameter of C2C12 myotubes in a dose‐dependent manner. Administration of 3,5‐DHBA also increased myotube diameter. Not only lactate but also 3,5‐DHBA upregulated the phosphorylation level of mitogen‐activated protein kinase kinase 1/2 (MEK1/2), p42/44 extracellular signal‐regulated kinase‐1/2 (ERK1/2) and p90 ribosomal S6 kinase (p90RSK). MEK inhibitor U0126 depressed the phosphorylation of ERK‐p90RSK and increase in myotube diameter induced by lactate. On the other hand, both lactate and 3,5‐DHBA failed to induce significant responses in the phosphorylation level of Akt, mammalian target of rapamycin, p70 S6 kinase and protein degradation‐related signals. Conclusion: These observations suggest that lactate‐associated increase in the diameter of C2C12 myotubes is induced via activation of GRP81‐mediated MEK/ERK pathway. Extracellular lactate might have a positive effect on skeletal muscle size. [ABSTRACT FROM AUTHOR]

The authors are reporting for the first time the fabrication of GaN‐based fully‐vertical high‐power metal‐oxide‐semiconductor field effect transistors on Si. The electrical measurements of the fabricated device exhibited both vertical and lateral modes of operation. The transfer characteristics of the device in vertical mode showed a peak trans‐conductance (Gm,max) of 23.6 mS/mm with a threshold voltage (Vth) of −19.6 V. The maximum current drain density (ID,max) of 249.3 mA/mm was observed with ON‐resistance (RON) of 44.2 Ω‐mm. The electrical results obtained in the vertical mode were also compared with the laterally oriented devices. The comparison of the electrical results indicates a relatively higher ON‐resistance of the device in the vertical configuration, due to the contribution of the series resistance of the buffer layers in the epi‐structure. [ABSTRACT FROM AUTHOR]

Aim The effects of heat shock transcription factor 1 ( HSF1) deficiency on the fibre type composition and the expression level of nuclear factor of activated T cells ( NFAT) family members ( NFATc1, NFATc2, NFATc3 and NFATc4), phosphorylated glycogen synthase kinase 3 α (p- GSK3 α) and p- GSK3 β, micro RNA-208b (miR-208b), miR-499 and slow myosin heavy chain (My HC) m RNAs (Myh7 and Myh7b) of antigravitational soleus muscle in response to unloading with or without reloading were investigated. Methods HSF1-null and wild-type mice were subjected to continuous 2-week hindlimb suspension followed by 2- or 4-week ambulation recovery. Results In wild-type mice, the relative population of slow type I fibres, the expression level of NFATc2, p- GSK3 ( α and β), miR-208b, miR-499 and slow My HC m RNAs (Myh7 and Myh7b) were all decreased with hindlimb suspension, but recovered after it. Significant interactions between train and time (the relative population of slow type I fibres; P = 0.01, the expression level of NFATc2; P = 0.001, p- GSK β; P = 0.009, miR-208b; P = 0.002, miR-499; P = 0.04) suggested that these responses were suppressed in HSF1-null mice. Conclusion HSF1 may be a molecule in the regulation of the expression of slow My HC as well as miR-208b, miR-499, NFATc2 and p- GSK3 ( α and β) in mouse soleus muscle. [ABSTRACT FROM AUTHOR]

A study of metal-organic chemical vapor deposition (MOCVD) grown AlN nucleation layer (NL) on breakdown characteristics for GaN-on-Si is presented. It is widely believed that AlN NL can act as an insulator because of its large band gap ∼6.2 eV. On contrary, this study of AlN NL/Si reveals conductive nature and shows high vertical leakage. The structural examinations along with electrical characterization show AlN NL/Si quality depends on the growth temperature. The surface morphology and presence of unintentional oxygen impurities govern the vertical leakage of AlN NL/Si. Interestingly, the AlN NL influences the growth of subsequent epitaxial layers as well as their vertical breakdown voltages (BVs). Further, it is found that AlGaN intermediate layer and multipairs of AlGaN/AlN strained layer superlattice (SLS) grown over AlN NL with better surface properties enhances the vertical BV. A high BV of 1.3 kV is achieved for SLS multipairs with a total thickness of 4.4 μm and the translated breakdown field strength is 2.8 MV cm−1 for MOCVD grown GaN-on-Si. [ABSTRACT FROM AUTHOR]

Aim Effects of heat shock transcription factor 1 ( HSF1) deficiency on heat stress-associated increase in slow soleus muscle mass of mice were investigated. Methods Both HSF1-null and wild-type mice were randomly assigned to control and heat-stressed groups. Mice in heat-stressed group were exposed to heat stress (41 °C for 60 min) in an incubator without anaesthesia. Results Significant increase in wet and dry weights, and protein content of soleus muscle in wild-type mice was observed seven days after the application of the heat stress. However, heat stress had no impact on soleus muscle mass in HSF1-null mice. Neither type of mice exhibited much effect of heat stress on HSF mRNA expression ( HSF1, HSF2 and HSF4). On the other hand, heat stress upregulated heat shock proteins ( HSPs) at the mRNA ( HSP72) and protein ( HSP72 and HSP110) levels in wild-type mice, but not in HSF1-null mice. The population of Pax7-positive nuclei relative to total myonuclei of soleus muscle in wild-type mice was significantly increased by heat stress, but not in HSF1-null mice. Furthermore, the absence of HSF1 gene suppressed heat stress-associated phosphorylation of Akt and p70 S6 kinase (p-p70S6K) in soleus muscle. Conclusion Heat stress-associated increase in skeletal muscle mass may be induced by HSF1 and/or HSF1-mediated stress response that activates muscle satellite cells and Akt/p70S6K signalling pathway. [ABSTRACT FROM AUTHOR]

Caffeine activates 5′AMP-activated protein kinase (AMPK), a signalling intermediary implicated in the regulation of glucose, lipid and energy metabolism in skeletal muscle. Skeletal muscle expresses two catalytic α subunits of AMPK, α1 and α2, but the isoform specificity of caffeine-induced AMPK activation is unclear. The aim of this study was to determine which α isoform is preferentially activated by caffeine in vitro and in vivo using rat skeletal muscle. Rat epitrochlearis muscle was isolated and incubated in vitro in the absence or presence of caffeine. In another experiment, the muscle was dissected after intravenous injection of caffeine. Isoform-specific AMPK activity, the phosphorylation status of AMPKα Thr and acetyl-CoA carboxylase (ACC) Ser, the concentrations of ATP, phosphocreatine (PCr) and glycogen, and 3- O-methyl--glucose (3MG) transport activity were estimated. Incubation of isolated epitrochlearis muscle with 1 m of caffeine for 15 min increased AMPKα1 activity, but not AMPKα2 activity; concentrations of ATP, PCr and glycogen were not affected. Incubation with 3 m of caffeine activated AMPKα2 and reduced PCr and glycogen concentrations. Incubation with 1 m of caffeine increased the phosphorylation of AMPK and ACC and enhanced 3MG transport. Intravenous injection of caffeine (5 mg kg) predominantly activated AMPKα1 and increased 3MG transport without affecting energy status. Our results suggest that of the two α isoforms of AMPK, AMPKα1 is predominantly activated by caffeine via an energy-independent mechanism and that the activation of AMPKα1 increases glucose transport and ACC phosphorylation in skeletal muscle. [ABSTRACT FROM AUTHOR]

The surface passivation for InGaN/GaN multilayer solar cells was investigated, and it was confirmed that the device with an atomic‐layer‐deposited (ALD) Al2O3 passivation film showed high internal and external quantum efficiencies of 99 and 84%, respectively, along with a high energy conversion efficiency of 1.31% under a 1‐sun air‐mass 1.5 global illumination. The current−voltage characteristics indicated that the ALD Al2O3 film improved the surface electrical stability. The carrier lifetime measurements revealed that the ALD Al2O3 film reduced the surface carrier recombination rate and thereby contributed to the improvement of the solar cell performance in a short wavelength region. [ABSTRACT FROM AUTHOR]

The article discusses research done on phosphorylated chitin (P-chitin), a material which has potential biomedical applications related to tissue regeneration. The P-chitin was synthesized using the H3PO4/P2O5/ET3PO4/hexanol method, the article states. Topics include the unique polysaccharide architecture of chitin, the structural similarity of chitin to cellulose, and the generation of new bifunctional materials by means of chemically modifying chitin. Also discussed is the selection of the synthesis process in order to obtain products free of biologically hazardous chemical compounds.

AIM: The purpose of this study was to develop a 32-item scale to assess postoperative dysfunction in patients who underwent surgery for gastric and oesophageal cancer and to evaluate its reliability and validity. BACKGROUND: For the objective assessment of postoperative dysfunction in patients with upper gastointestinal cancer, we performed a preliminary survey by mail using a 34-item questionnaire as a initial version. The results of the survey were assessed by item analysis of the scale. The scale items were further refined by researchers and specialists, and a 32-item scale for the assessment of postoperative dysfunction (initial scale) was developed. METHODS: Using this 32-item scale (initial scale), a mail survey was performed of 379 subjects selected by random sampling. RESULTS: The questionnaire was returned by 292 patients (77.1%) and 283 responses (74.7%) were valid. Of these, 221 respondents had gastric cancer and 62 oesophageal cancer. The mean age of respondents was 64.9 SD 9.8 (range 35-89) years. The mean total score of the 32-items on the initial version for the assessment of postoperative dysfunction was 60.8 SD 16.7. The mean total score for gastric cancer patients and oesophageal cancer patients was 58.1 SD 15.8 and 70.1 SD 16.7 respectively. After the elimination of scale items regarded as irrelevant based on statistical considerations and the judgement of experts, factor analysis was performed. Seven factors were valid: 'regurgitation reflux', 'limited activity because of decreased food consumption', 'passage dysfunction immediately after eating', 'dumping-like symptoms', 'transfer dysfunction', 'hypoglycaemic symptoms' and 'diarrhoea-like symptoms'. The cumulative proportion of variance by scale reliability was confirmed by a Cronbach's alpha-coefficient of 0.926. The Cronbach's alpha-coefficient for all 32 items on the initial version was 0.926, the Cronbach's alpha-coefficient for sub-items was 0.705-0.856, and Pearson's correlation coefficient of re-test for the total score of the 32 items was 0.865, which confirmed a high degree of internal consistency. The construct validity of the scale was confirmed using the known-group technique by operative procedures, and from the result of factorial validity. This scale was named 'Postoperative Dysfunction for Upper Gastrointestinal Cancer 32; PODUGC-32'. CONCLUSION: This scale is sufficiently reliable and valid and will be useful clinically. Relevance to clinical practice. We can use the new scale to assess postoperative dysfunction in patients with upper gastointestinal cancer for nursing practice. [ABSTRACT FROM AUTHOR]

Background and Purpose: We previously demonstrated that chronic hyperinsulinaemia induced by drinking high levels of fructose augments adrenergic nerve-mediated vasoconstriction and suppresses vasodilatation mediated by calcitonin gene-related peptide (CGRP)-containing (CGRPergic) vasodilator nerves. In this study, the effects of pioglitazone on vascular responses induced by stimulation of adrenergic nerves, CGRPergic nerves and vasoactive agents were investigated in pithed rats given 15% fructose solution to drink (FDR).Experimental Approach: To assess the effect of pioglitazone on the altered vascular responsiveness in the hyperinsulinaemic state in vivo, changes in vascular responses to spinal cord stimulation (SCS) and intravenous bolus injections of noradrenaline, angiotensin II and CGRP were evaluated in pithed control rats and FDR either untreated or treated with pioglitazone.Key Results: In the pithed FDR, vasoconstrictor responses to SCS and to injections of noradrenaline and angiotensin II were significantly greater than those of pithed control rats. In pithed FDR with artificially increased blood pressure and blockade of the autonomic ganglia, the vasodilator responses to SCS and CGRP injection were significantly smaller than those of pithed control rats. Oral administration of pioglitazone to FDR for two weeks markedly decreased plasma levels of insulin, triglycerides and blood glucose. In FDR pioglitazone diminished the augmented vasoconstrictor responses to SCS, noradrenaline and angiotensin II, and ameliorated the decrease in vasodilator responses to SCS.Conclusions and Implications: The present results suggest that pioglitazone improves not only insulin resistance, but also the dysfunctions in vascular control regulated by adrenergic and CGRPergic nerves in the hyperinsulinaemic state. [ABSTRACT FROM AUTHOR]

A high current gain cutoff frequency (fT) of 90 GHz and a peak maximum oscillation frequency (fMAX) as high as 150 GHz are reported for a rectangular‐shaped gate AlGaN/GaN high‐electron mobility transistor (HEMT) on a high resistive silicon (HR‐Si) substrate. The combined high fT/fMAX values for 100 nm unpassivated gate device demonstrate the high‐quality heterostructure on silicon substrate. The reported high‐performance RF device characteristics are comparable and even superior to the existing passivated AlGaN/GaN HEMTs of similar gate length. In addition, good DC characteristics have been recorded with the drain current density and an extrinsic transconductance of 0.6 A/mm and 157 mS/mm, respectively. [ABSTRACT FROM AUTHOR]

An application for a transparent gate electrode with surface‐side electroluminescence (EL) observation is proposed for identification of the gate leakage path in AlGaN/GaN high electron mobility transistors. This technique enables surface‐side EL observation throughout the gate electrode, so that the substrate material is unrestricted. Through the transparent gate, a non‐uniformly located spot‐shape EL was clearly observed. By comparing devices with different leakage currents using EL intensity, the location marked by the spot‐shape EL is found and demonstrates a dominant leakage path. [ABSTRACT FROM AUTHOR]

The realisation of a fully vertical gallium nitride (GaN)-on-silicon (Si) Schottky barrier diode (SBD) without using wafer bonding and Si substrate removal process is reported. The SBD presented a turn-on voltage of 0.69 V at 1 A/cm², breakdown voltage of 148 V with a specific on-resistance of 13.9 mO cm². The ideality factor and Schottky barrier height were 1.35 and 0.71 eV, respectively. An effective critical electric field was estimated to be 1.48 MV/cm. The Baliga's figure of merit for the SBD was calculated to be 1.57 MW/cm². These results indicate the great potential of GaNon- Si in achieving cost-effective fully vertical power device. [ABSTRACT FROM AUTHOR]

PURPOSE. To examine the validity of the nursing diagnosis body image disturbance and to specify its major and minor defining characteristics in Japanese culture. METHODS. A qualified sample of 149 RNs with an average of 10 years of clinical experience and knowledge of nursing diagnosis was given a questionnaire consisting of 21 defining characteristics from NANDA, 8 additional items from the literature, and 2 distracting characteristics. FINDINGS. Four major diagnostic content validation (DCV) scores of 0.75 and higher and 15 minor defining characteristics with DCV scores from 0.60 to 0.74 were identified. CONCLUSIONS. This study provides a foundation for further study of culturally appropriate defining characteristics for use in Japan. [ABSTRACT FROM AUTHOR]

Aims: The present study aimed to evaluate the associations between medication use and falls and to identify high risk medications that acted as a trigger for the onset of falls in an acute care hospital setting., Methods: We applied a case-crossover design wherein cases served as their own controls and comparisons were made within each participant. The 3-day period (days 0 to -2) and the 3-day periods (days -6 to -8, days -9 to -11 and days -12 to -14) before the fall event were defined as the case period and the control periods, respectively. Exposures to medications were compared between the case and control periods. Odds ratios (OR) and 95% confidence intervals (CI) for the onset of falls with respect to medication use were computed using conditional logistic regression analyses., Results: A total of 349 inpatients who fell during their hospitalization were recorded on incident report forms between March 2003 and August 2005. The initial use of antihypertensive, antiparkinsonian, anti-anxiety and hypnotic agents as medication classes was significantly associated with an increased risk of falls, and these ORs (95% CI) were 8.42 (3.12, 22.72), 4.18 (1.75, 10.02), 3.25 (1.62, 6.50) and 2.44 (1.32, 4.51), respectively. The initial use of candesartan, etizolam, biperiden and zopiclone was also identified as a potential risk factor for falls., Conclusions: Medical professionals should be aware of the possibility that starting a new medication such as an antihypertensive agent, including candesartan, and antiparkinsonian, anti-anxiety and hypnotic agents, may act as a trigger for the onset of a fall.

We performed periodical foot care intervention including nail drilling combined with topical antifungal application for 6 months or more in 24 diabetic patients with onychomycosis who were not receiving oral antifungals, and evaluated its effects. The type of onychomycosis was superficial white onychomycosis (SWO) in eight patients, and distal-lateral subungual onychomycosis (DLSO) in 16. The state of onychomycosis was evaluated according to the Scoring Clinical Index for Onychomycosis (SCIO). Of the eight patients with SWO, none showed aggravation of the onychomycosis state, and two were cured 6 months after the initiation of intervention and two after 1 year (total of four patients, 50%). In the patients with DLSO, the SCIO score was 18.1 +/- 6.5 before intervention but significantly decreased to 14.6 +/- 6.6 6 months after intervention. In 12 patients who we were able to consecutively follow up for 1 year, the SCIO score also significantly decreased compared with the score before intervention. Thus, foot care intervention including nail drilling combined with topical antifungal application had effects on onychomycosis and achieved cure in some patients with SWO. In addition, intervention increased patients' awareness of foot care, showing educational effects. Therefore, foot care intervention including nail drilling may be useful.

A recombinant form of D-3-hydroxybutyrate dehydrogenase (EC 1.1.1.30) from Pseudomonas fragi has been crystallized by the hanging-drop method using PEG 3000 as a precipitating agent. The crystals belong to the orthorhombic group P2(1)2(1)2, with unit-cell parameters a = 64.3, b = 99.0, c = 110.2 A. The crystals are most likely to contain two tetrameric subunits in the asymmetric unit, with a VM value of 3.29 A3 Da(-1). Diffraction data were collected to a 2.0 A resolution using synchrotron radiation at the BL6A station of the Photon Factory.