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Chlorogenic acid is an ester of caffeic and quinic acids, and is one of the most widely consumed polyphenols because it is abundant in foods, especially coffee. We explored whether chlorogenic acid and its metabolite, caffeic acid, act directly on skeletal muscle to stimulate 5'-adenosine monophosphate-activated protein kinase (AMPK). Incubation of rat epitrochlearis muscles with Krebs buffer containing caffeic acid (≥0.1 mM, ≥30 min) but not chlorogenic acid increased the phosphorylation of AMPKα Thr(172), an essential step for kinase activation, and acetyl CoA carboxylase Ser(79), a downstream target of AMPK, in a dose- and time-dependent manner. Analysis of isoform-specific AMPK activity revealed that AMPKα2 activity increased significantly, whereas AMPKα1 activity did not change. This enzyme activation was associated with a reduction in phosphocreatine content and an increased rate of 3-O-methyl-d-glucose transport activity in the absence of insulin. These results suggest that caffeic acid but not chlorogenic acid acutely stimulates skeletal muscle AMPK activity and insulin-independent glucose transport with a reduction of the intracellular energy status. [ABSTRACT FROM AUTHOR]

Abstract: The AlGaN/GaN high-electron-mobility transistors (HEMTs) fabrication and its dc characteristics have been performed on both 4-in. diameter Si and sapphire substrates. Due to the high crystalline quality with one order low dislocation density of GaN on sapphire substrate, better 2DEG mobility with high values of drain current density (511mA/mm) and extrinsic transconductance (198mS/mm) were observed. Large OFF-state breakdown voltage (BVgd) with low gate leakage current was observed on sapphire-based HEMTs. Though the sapphire-based HEMTs show better characteristics than Si-based HEMTs, the thermal dissipation from the device is not good enough. The low thermal resistance of Si-based HEMTs leads the existence of high ON-state BVgd. This has been confirmed by measuring the device surface temperature (T D) by infrared microscope camera. Higher value of T D =74°C at V DS =20V and V GS =+1.5V was observed on sapphire-based single finger 400-μm-wide and 2-μm-gate-length HEMTs when compared to the HEMTs on Si (T D =41°C). The measured T D has been directly correlated with the measured drain current reduction (I Dreduc.) due to self-heating. About 83% of high rate of increase in temperature by self-heating was observed on sapphire-based HEMTs when compared to Si-based HEMTs. The device thermal impedance (R th) of Si- and sapphire-based AlGaN/GaN HEMTs are 44 and 139°C/W, respectively. The ratio of R thSi/R thSapp =0.30 obtained from our studies is consistent with the reported values of 0.297. The 4-in. diameter Si has been shown to be a viable alternative substrate for low-cost high-power operating GaN HEMTs. [Copyright &y& Elsevier]

Abstract: GaN/In x Al1−x N quantum wells with varying In composition in the In x Al1−x N barrier and varying GaN well thickness were grown by metal–organic vapor phase epitaxy on a c-plane sapphire. The as-grown samples were characterized by high resolution X-ray diffraction to determinate the composition and the relaxation state. The surface was observed by atomic force microscopy and the photoluminescence was measured at low temperature. A competition between the confinement effect and electric field effect has been evidenced. Under a critical well thickness, the luminescence is blue-shifted with the decrease of the In composition while above this critical thickness, the opposite behavior is observed. [Copyright &y& Elsevier]

AIM OF THE STUDY: Morus alba (mulberry) leaf is a natural therapeutic agent that has been shown to have an antidiabetic effect. We explored the possibility that 5'-AMP-activated protein kinase (AMPK) is involved in metabolic enhancement by the Morus alba leaf. MATERIALS AND METHODS: Isolated rat epitrochlearis muscle was incubated in a buffer containing Morus alba leaf hot water extract (MLE) and the AMPK activation and related events were examined. RESULTS: In response to MLE treatment, the Thr(172) phosphorylation of the catalytic alpha subunit of AMPK, an essential step for full kinase activation increased in a dose- and time-dependent manner. Ser(79) phosphorylation of acetyl CoA carboxylase, an intracellular substrate of AMPK, increased similarly. Analysis of isoform-specific AMPK activity revealed that MLE activated both the alpha1 and alpha2 isoforms of the catalytic subunit. This increase in enzyme activity was associated with an increased rate of 3-O-methyl-D-glucose transport in the absence of insulin and with phosphorylation of AS160, a signaling intermediary leading to glucose transporter 4 translocation. The intracellular energy status, estimated from the ATP and phosphocreatine concentrations, was not affected by MLE. CONCLUSION: MLE stimulates skeletal muscle AMPK activity acutely without changing the intracellular energy status. [ABSTRACT FROM AUTHOR]

Abstract: Δ9-Tetrahydrocannabinol (THC) has been reported to induce catalepsy-like immobilization, but the mechanism underlying this effect remains unclear. In the present study, in order to fully understand the neural circuits involved, we determined the brain sites involved in the immobilization effect in rats. THC dose-dependently induced catalepsy-like immobilization. THC-induced catalepsy-like immobilization is mechanistically different from that induced by haloperidol (HPD), because unlike HPD-induced catalepsy, animals with THC-induced catalepsy became normal again following sound and air-puff stimuli. THC-induced catalepsy was reversed by SR141716, a selective cannabinoid CB1 receptor antagonist. Moreover, THC-induced catalepsy was abolished by lesions in the nucleus accumbens (NAc) and central amygdala (ACE) regions. On the other hand, HPD-induced catalepsy was suppressed by lesions in the caudate putamen (CP), substantia nigra (SN), globus pallidus (GP), ACE and lateral hypothalamus (LH) regions. Bilateral microinjection of THC into the NAc region induced catalepsy-like immobilization. This THC-induced catalepsy was inhibited by serotonergic drugs such as 5-hydroxy-L-tryptophan (5-HTP), a 5-HT precursor, and 5-methoxy-N,N-dimethyltryptamine (5-MeODMT), a 5-HT receptor agonist, as well as by anti-glutamatergic drugs such as MK-801 and amantadine, an N-methyl-d-aspartate (NMDA) receptor antagonist. THC significantly decreased 5-HT and glutamate release in the NAc, as shown by in vivo microdialysis. SR141716 reversed and MK-801 inhibited this decrease in 5-HT and glutamate release. These findings suggest that the THC-induced catalepsy is mechanistically different from HPD-induced catalepsy and that the catalepsy-like immobilization induced by THC is mediated by decreased 5-HT neurotransmission in the nucleus accumbens due to the action of glutamate-containing neurons. [Copyright &y& Elsevier]

Recent progress in GaN based high electron mobility transistors (HEMTs) has revealed them to be strong candidates for future high power devices with high frequency operation. In order to extract and utilize the favorable GaN material properties, however, there is still a lot to be investigated. Reduction of the gate leakage current is one of the key issues to be solved for their further improvement. A high work function metal such as Pt, Ir, Pd or Mo was inserted to the conventional Ni/Au Schottky contact to n-GaN and AlGaN/GaN epilayers, and the Schottky diodes were studied in detail with respect to the thermal annealing in nitrogen ambient. The electrical characteristics were found to be changed by the thermal treatment in each device. A drastic improvement was attained in the Ni/Pt(Ir)/Au system whereas degradation occurred in Ni/Mo/Au by RTA at 500 °C for 5 min. These phenomena were confirmed to be dependent on the work function of each inserted metal. The role of Ni in the Ni/Pt/Au system was also investigated, and it was found to be essential in obtaining better electrical performance in comparison with the diodes without Ni, such as Pt/Au or Ir/Au Schottky electrodes. The AlGaN/GaN HEMTs were fabricated using Ni/Pt/Au gate contacts. Reduction of the gate leakage current by as much as four orders of magnitude was successfully recorded by thermal annealing without degrading the transconductance of the transistor, and it was concluded that this technique was promising for high power AlGaN/GaN HEMT electronics. [Copyright &y& Elsevier]

Background The emetogenic classification of antineoplastic agents has provided a framework for defining antiemetic treatment recommendations in international guidelines. The most widely used classification schema identified four emetic risk levels. However, information on the emetogenicity of each chemotherapeutic regimen is insufficient. We previously reported that the emetic risk of pemetrexed was higher than that of taxans. Risk factors for chemotherapy-induced nausea and vomiting (CINV) were also assessed in patients with lung cancer receiving carboplatin plus pemetrexed (CBDCA+PTX) or carboplatin plus paclitaxel (CBDCA+PEM), and the CINV incidence was compared between these two regimens. Methods Data were pooled from two prospective studies, and propensity score matching was used to compare the CINV incidence between CBDCA+PTX and CBDCA+PEM groups. Risk factors for CINV were identified using logistic regression models. The pattern of CINV occurrence was evaluated by 7-day patient diary for recording CINV after the commencement of chemotherapy. Results Among 240 evaluable patients, the CINV incidence was higher in the CBDCA+PEM group than in the CBDCA+PTX group at the delayed phase (nausea: 51.1% vs. 36.2%, P = 0.040; vomiting: 23.4% vs. 14.9%, P = 0.138). The pattern of delayed CINV occurrence peaked on days 5 and 4 for CBDCA+PEM and CBDCA+PTX regimens, respectively. Logistic regression analysis identified younger age, female sex, no alcohol consumption, two antiemetics, and CBDCA+PEM regimen as independent risk factors associated with delayed nausea, and female sex and two antiemetics for delayed vomiting. Conclusions The emetic risk of CDBCA+PEM regimen was higher than that of CBDCA+PTX regimen. More aggressive antiemetic prophylaxis such as quadruple therapy, including olanzapine, may be considered in patients receiving CDBCA+PEM regimen. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background Delayed chemotherapy-induced nausea and vomiting (CINV) is not well controlled in patients with colorectal cancer (CRC) treated with oxaliplatin (L-OHP)-based chemotherapy. Whether adding a neurokinin-1 receptor antagonist to a first-generation 5HT3 antagonist (1st-5HT3RA) and dexamethasone (DEX) is beneficial in patients on L-OHP-based chemotherapy is controversial. It is unclear whether palonosetron (PALO) or aprepitant (APR) is more effective in controlling delayed CINV. We, therefore, investigated whether PALO+DEX (PALO group) or 1st-5HT3RA+DEX+APR (APR group) was more effective in controlling delayed CINV, as well as risk factors for delayed CINV, in patients with CRC treated with L-OHP-based chemotherapy. Methods We pooled data from two prospective observational studies in Japan and one phase III clinical trial and compared the incidence of CINV between the PALO and APR groups using propensity score-matched analysis. Risk factors for CINV were identified using logistic regression models. Results Among the 404 eligible patients, those in the PALO group showed a higher incidence of delayed CINV than those in the APR group (nausea: 43.4% vs. 32.4%, P = 0.061; vomiting: 12.5% vs. 4.4%, P = 0.017). The logistic regression analysis identified alcohol consumption, motion sickness, and PALO+DEX regimen as independent risk factors for delayed nausea, and female sex and PALO+DEX regimen as those for delayed vomiting. Conclusions Treatment with the three antiemetics, including APR, was more effective in controlling delayed CINV than prophylactic treatment with the two antiemetics, including PALO. Thus, patients with CRC receiving L-OHP-based chemotherapy should be treated with three antiemetics, including APR. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]