Design and implementation of a 150 GHz single-channel millimeter wave interferometer on Joint TEXT tokamak

A simple, single-channel millimeter-wave interferometer system has been designed, fabricated, and installed on the J-TEXT tokamak. For the plasma density anticipated on J-TEXT, a solid-state source operating at 150 GHz has been chosen to minimize errors due to both vibration along the beam path and refraction in the plasma. The new aspect of the interferometer design is to use a subharmonic mixer for detection with a frequency doubled 150 GHz source. It employs a single source which is bias-tuned and modulated with a sawtooth wave form up to 100 kHz in order to generate the intermediate frequency. The 12.5 GHz voltage-controlled oscillator is multiplied to 75 GHz before a final doubler raises it to 150 GHz. A portion of the 75 GHZ power is used for the local oscillator (LO) and is directly connected to the LO input of the subharmonic mixer. The phase is evaluated by a digital phase comparator using a software-based algorithm. Detection noise limits the minimum resolvable phase change with the interferometer to ±0.05 fringe, which corresponds to an averaged electron density change along the chord of ±1.1 × 10(17) m(-2). The maximum measurable electron density is expected to be ∼9 × 10(19) m(-3). A comparison of preliminary results from the millimeter wave interferometer with that from the far-infrared hydrogen cyanide laser (wavelength of 337 μm) interferometer shows good agreement during the pulse flat-top period. The millimeter wave interferometer system will be used as a part of the density feedback control system in the future.

Paradoxical role of autophagy in the dysplastic and tumor-forming stages of hepatocarcinoma development in rats

Many reports have shown that autophagy has a role as both a promoter and inhibitor in tumor development. However, the mechanism of this paradox is unknown. Tumor development is a multistep process. Therefore, we investigated whether the role of autophagy in hepatocarcinoma formation depended on the stage of tumor development. Based on our results, autophagy inhibition by chloroquine had a tumor-promotive effect in the rat model with N-diethylnitrosamine-induced hepatocarcinogenesis in its dysplastic stage (Ds) and a tumor-suppressive effect in its tumor-forming stage (Ts). In the Ds, autophagy inhibition enhanced cell proliferation, DNA damage and inflammatory cytokines expression in liver. These changes were dependent on the upregulation of reactive oxygen species (ROS) that was resulted from autophagy inhibition, and ultimately accelerated the process of hepatocarcinogenesis. However, in the Ts, autophagy inhibition restrained tumor formation by decreasing tumor cell survival and proliferation. In this stage, autophagy inhibition led to excessive ROS accumulation in the tumor, which promoted cell apoptosis, and prominently suppressed tumor cell metabolism. Taken together, our data suggested that autophagy suppressed hepatocarcinogenesis in the Ds by protecting normal cell stability and promoted hepatocarcinogenesis in the Ts by supporting tumor cells growth. Autophagy always had a role as a protector throughout the process of hepatocarcinoma development.

Prediction for relapse and prognosis of newly diagnosed epilepsy

OBJECTIVE

The objective of this study was to investigate the timing of therapy initiation and other clinical factors as potential predictors for relapse and prognosis of epilepsy, based on hospital-based prospective observational data in China.

METHODS

One hundred and seventy-one newly diagnosed patients with one or more seizures were recruited and followed for at least 2 years. Kaplan-Meier survival analysis was used for calculating recurrence and remission rates. Univariate and multivariate analyses for risk factors were performed using Cox proportional hazards model.

RESULTS

Among the 171 patients analyzed, more patients had partial (54.4%) than generalized seizures (45.6%). The range of patients' age was 6-70 years, but 70% were under 16 years of age. Multiple seizure types (HR = 2.01; 95% CI, 1.31-3.10), epileptiform electroencephalogram (EEG) abnormality (HR = 1.95; 95% CI, 1.09-3.49), and >1 seizure monthly before treatment (HR = 2.74; 95% CI, 1.69-4.51) were predictors of seizure recurrence. The best negative predictors of remission were as follows: relapse (HR = 0.13; 95% CI, 0.07-0.23) and epileptiform EEG within 1 year of treatment (HR = 0.61; 95% CI, 0.39-0.97). Delayed treatment after three or more seizures did not significantly increase the risk of recurrence (P = 0.70) or remission (P = 0.31) compared with early treatment after one or two seizures.

CONCLUSIONS

Multiple seizure types, epileptiform EEG abnormality, and >1 seizure monthly before treatment predict seizure recurrence. Relapse and epileptiform EEG within 1 year of treatment predict adverse seizure outcome. Early treatment does not affect relapse or prognosis.

Antiemetic effects of combined methylprednisolone and tropisetron in mastectomy

BACKGROUND

Combined dexamethasone and tropisetron have been reported more effective than a single drug therapy in preventing postoperative nausea and vomiting (PONV). However, the safety use of dexamethasone has been questioned recently because of the risk of secondary adrenal deficiency. Therefore, we hypothesized that combined tropisetron and methylprednisolone, a short-lasting corticoid, might provide effective prophylaxis of PONV with less effect on endogenous cortisol level.

METHODS

In this study, 224 women undergoing modified radical mastectomy under general anesthesia were randomly divided into three groups: 1) receiving 10 mg tropisetron alone (T, N.=76); 2) 10 mg tropisetron and 8 mg dexamethasone (TD, N.=73); or 3) 10 mg tropisetron and 40 mg methylprednisolone (TM, N.=75) intravenously. Serum cortisol level, episodes of PONV and the need for rescue antiemetic medication were recorded during first 3 days after surgery.

RESULTS

Serum cortisol significantly decreased in group TD (5.42±1.87 μg/dL), compared with group TM (14.38±2.01 μg/dL, P<0.01) and group T (19.52±1.53 μg/dL, P<0.001) in the first day postoperatively. In the first 24 hours, the incidence of vomiting was significantly higher in group T (15.8%), compared with group TD (5.5%, P<0.05) and group TM (5.3%, P<0.05), respectively. The overall request for a rescue antiemetic of group T was significantly higher, compared with group TD and group TM (P<0.05).

CONCLUSION

Methylprednisolone-tropisetron combination is more effective than tropisetron alone, and as equally effective as dexamethasone-tropisetron combination for preventing acute PONV in mastectomy.

Selenoprotein P and Yunnan endemic sudden cardiac death--an ecological study

The aim of the present study was to explore the role of selenoprotein P (SePP) in the etiology of the endemic sudden cardiac death in Yunnan, China. The levels of SePP of 124 subjects and glutathione peroxidase (GPx) of 119 subjects were measured. The subjects were from the old and new endemic areas and non-endemic areas. The levels of SePP and GPx of the subjects of the old endemic area were significantly higher than those of the subjects of the new endemic area and the non-endemic areas, respectively. The Pearson's correlation among SePP, GPx, and the number of the incident cases of the disease were statistically significant. These correlations show that there is an inverse relationship among the number of patients and the levels of SePP (r  =  - 0.9800, P  =  0.0200) and GPx (r  =  - 0.961, P  =  0.009). The results show that selenium deficiency might play an important role in the incidence of the disease.

Fabrication and Evaluation of Curcumin-loaded Nanoparticles Based on Solid Lipid as a New Type of Colloidal Drug Delivery System

Curcumin has very broad spectrum of biological activities; however, photodegradation, short half-life and low bioavailability have limited its clinical application. Curcumin-loaded solid lipid nanoparticles were studied to overcome these problems. The aim of this study was to optimize the best formulation on curcumin-loaded solid lipid nanoparticles. Emulsion-evaporation and low temperature-solidification technique was applied with monostearin as lipid carriers. The single factor analysis and orthogonal design were used to optimize formulation and various parameters were investigate. By the optimisation of a single factor analysis and orthogonal test, the particles size, polydispersity index, zeta potential, encapsulation efficiency and drug loading capacity of the optimised formulation were 99.99 nm, 0.158, -19.9 mV, 97.86%, and 4.35%, respectively. The differential scanning calorimetry and X-ray diffraction analysis results demonstrated new structure was formed in nanoparticles. The release kinetics in vitro demonstrated curcumin-loaded solid lipid nanoparticles can control drug release. These studies confirmed that curcumin-loaded solid lipid nanoparticles could be prepared successfully with high drug entrapment efficiency and loading capacity. Curcumin-loaded solid lipid nanoparticles may be a promising drug delivery system to control drug release and improve bioavailability.

Effects of subacute exposure to 1,2-dichloroethane on mouse behavior and the related mechanisms

The aim of this study was to explore the effects of subacute exposure to 1,2-dichloroethane (1,2-DCE) on mouse behavior and the related mechanisms focusing on alteration of oxidative stress and amino acid neurotransmitters in the brain. Mouse behavior was examined by open field test. Levels of nitric oxide (NO), malondialdehyde (MDA) and nonprotein sulfhydryl (NPSH) and activity of inducible nitric oxide synthase (iNOS) and superoxide dismutase (SOD) were determined by colorimetric method. Contents of glutamate (Glu), aspartate (Asp) and gamma-aminobutyric acid (GABA) were evaluated by high-performance liquid chromatography. Reduced locomotor and exploratory activities and increased anxiety were found in 0.45 and 0.9 g/m3 1,2-DCE-treated mice. In contrast, increased excitability was found in 0.225 g/m3 1,2-DCE-treated mice. Compensatory antioxidant status and increased NOS activity and NO level in the brain were found in 1,2-DCE-treated mice. Moreover, Glu contents in 1,2-DCE-treated mice and GABA contents in 0.9 g/m3 1,2-DCE-treated mice increased, whereas GABA contents in 0.225 g/m3 1,2-DCE-treated mice decreased significantly compared with control. Taken together, our results suggested that mouse behavior could be disturbed by subacute exposure to 1,2-DCE, and the changes of amino acid neurotransmitter in the brain might be related to the behavioral effects.

Final follow-up of the Multicentre Aneurysm Screening Study (MASS) randomized trial of abdominal aortic aneurysm screening

BACKGROUND

The long-term effects of abdominal aortic aneurysm (AAA) screening were investigated in extended follow-up from the UK Multicentre Aneurysm Screening Study (MASS) randomized trial.

METHODS

A population-based sample of men aged 65-74 years were randomized individually to invitation to ultrasound screening (invited group) or to a control group not offered screening. Patients with an AAA (3·0 cm or larger) detected at screening underwent surveillance and were offered surgery after predefined criteria had been met. Cause-specific mortality data were analysed using Cox regression.

RESULTS

Some 67 770 men were enrolled in the study. Over 13 years, there were 224 AAA-related deaths in the invited group and 381 in the control group, a 42 (95 per cent confidence interval 31 to 51) per cent reduction. There was no evidence of effect on other causes of death, but there was an overall reduction in all-cause mortality of 3 (1 to 5) per cent. The degree of benefit seen in earlier years of follow-up was slightly diminished by the occurrence of AAA ruptures in those with an aorta originally screened normal. About half of these ruptures had a baseline aortic diameter in the range 2·5-2·9 cm. It was estimated that 216 men need to be invited to screening to save one death over the next 13 years.

CONCLUSION

Screening resulted in a reduction in all-cause mortality, and the benefit in AAA-related mortality continued to accumulate throughout follow-up.

REGISTRATION NUMBER

ISRCTN37381646 (http://www.controlled-trials.com).

Recent progress of the HCN interferometer on J-TEXT tokamak

A multichannel far-infrared HCN laser interferometer has been developed to measure plasma electron density for the J-TEXT tokamak. Initial operation of a seven chords system with 7 cm spacing and a 0.1 ms temporal resolution is described. Density modulation experiments in J-TEXT show that it is possible to obtain information on particle transport by precise measurement of the density perturbation amplitude and phase spatial variation. An optical configuration upgrade has been implemented in order to improve phase resolution.

First results from the J-TEXT high-resolution three-wave polarimeter-interferometer

A laser-based far-infrared polarimeter-interferometer system utilizing the three-wave technique has been implemented on the J-TEXT tokamak. The polarimeter determines the Faraday effect by measuring the phase difference between two collinear, counter-rotating, circularly polarized laser beams. The first results of the polarimeter-interferometer designed for J-TEXT have been obtained in the most recent J-TEXT experimental campaign. Simultaneous polarimetric and interferometric measurement is achieved, with phase resolution up to 0.1°, at bandwidth of 50 kHz. The temporal resolution, which is dependent on the laser's frequency offset, is ∼1 μs. Continual spatial measurement covering 45 cm (80% of the plasma cross-section) is realized by utilizing 1D parabolic beam expansion optics. Three initial test chords are installed and future plans call for expansion up to 30 chords with 1.5 cm chord spacing, providing high spatial resolution for measurement of electron density and current density profiles. Reliability of both polarimetric and interferometric measurement is confirmed by comparison with computation and data from a hydrocyanic acid (HCN) interferometer. With the high temporal and phase resolution, perturbations associated with the sawtooth cycle and MHD activity have been observed.

Vibration mitigation in J-TEXT far-infrared diagnostic systems

Optical structure stability is an important issue for far-infrared (FIR) phase measurements. To ensure good signal quality, influence of vibration should be minimized. Mechanical amelioration and optical optimization can be taken in turn to decrease vibration's influence and ensure acceptable measurement. J-TEXT (Joint Texal Experiment Tokamak, formerly TEXT-U) has two FIR diagnostic systems: a HCN interferometer system for electron density measurement and a three-wave polarimeter-interferometer system (POLARIS) for electron density and Faraday effect measurements. All use phase detection techniques. HCN interferometer system has almost eliminated the influence of vibration after mechanical amelioration and optical optimization. POLARIS also obtained first experimental results after mechanical stability improvements and is expected to further reduce vibration's influence on Faraday angle to 0.1° after optical optimization.

Biomarkers in the lung cancer diagnosis: a clinical perspective

The propensity for tumor biomarkers to be detected in serum at an early disease stage has become an area of interest for clinicians. This study aimed to evaluate the efficiency of 7 tumor biomarkers, namely, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cytokeratin 19 (CYFRA-21-1), alpha-fetoprotein, carbohydrate antigen-125 (CA-125), carbohydrate antigen-19.9 (CA-19.9), and ferritin, independently or in combination for the diagnosis of lung cancer. Electrochemiluminescence immunization was used to determine biomarker levels expressed in 530 patients with pulmonary disease and 229 healthy subjects. The observed levels of CEA, NSE, CYFRA-21-1, CA-125, and CA-19.9 in patients with pathologically confirmed lung cancer were significantly higher than those in patients with benign pulmonary disease or control subjects. Adenocarcinoma, squamous cell carcinoma, and small cell carcinoma of the lung were associated with the highest observed levels of CA-125, CYFRA-21-1, and NSE, respectively. Combining biomarkers successfully led to the diagnosis of lung cancer. CEA + NSE + CA-125 showed the highest sensitivity for small cell carcinoma, at 83.33%, whereas CEA + NSE + CYFRA-21-1 + CA-125 showed 94.11% sensitivity for squamous cell carcinoma. The combination of 6 biomarkers, namely, CEA + NSE + CYFRA-21-1 + CA-125 + ferritin + CA-19.9, showed 80.49% sensitivity for adenocarcinoma. Combining biomarkers significantly aided in the diagnosis of lung cancer. However, this increased sensitivity on combination was accompanied by a decreased specificity for lung cancer subtypes. Combining biomarkers appropriately increases their sensitivity and helps with the diagnosis of lung cancer.

Magnetic field generation by the Rayleigh-Taylor instability in laser-driven planar plastic targets

Magnetic fields generated by the Rayleigh-Taylor instability were measured in laser-accelerated planar foils using ultrafast proton radiography. Thin plastic foils were irradiated with ∼4-kJ, 2.5-ns laser pulses focused to an intensity of ∼10(14)  W/cm(2) on the OMEGA EP Laser System. Target modulations were seeded by laser nonuniformities and amplified during target acceleration by the Rayleigh-Taylor instability. The experimental data show the hydrodynamic evolution of the target and MG-level magnetic fields generated in the broken foil. The experimental data are in good agreement with predictions from 2-D magnetohydrodynamic simulations.

Non-Rayleigh scattering behavior for anisotropic Rayleigh particles

Derived from the light scattering by a radially anisotropic sphere, unusual scattering behavior is exhibited, which breaks the Rayleigh law (scattering efficiency Q(sca)~q(4) as q→0, where q is the size parameter). Under certain conditions, we demonstrate an asymptotical relation between Q(sca) and q, i.e., Q(sca)=Fq(8), which is not realizable for isotropic particles in Rayleigh regime. Moreover, suitable adjustment of the anisotropic parameters can further suppress the coefficient F, resulting in enhanced transparency of the anisotropic particle.

The p47phox- and NADPH oxidase organiser 1 (NOXO1)-dependent activation of NADPH oxidase 1 (NOX1) mediates endothelial nitric oxide synthase (eNOS) uncoupling and endothelial dysfunction in a streptozotocin-induced murine model of diabetes

AIMS/HYPOTHESIS

We have previously shown that NADPH oxidase (NOX) lies upstream of uncoupled endothelial nitric oxide synthase (eNOS), which is known to occur in diabetic endothelium. However, it remains unclear which specific NOX isoform(s) is responsible for eNOS uncoupling and endothelial dysfunction in diabetic mouse models. The aim of the present study was to test the hypothesis that one or more NOX isoform(s) mediate(s) diabetic uncoupling of eNOS, which has been shown to occur in patients with diabetes to contribute to endothelial dysfunction.

METHODS

Diabetes was induced by streptozotocin administration. The N (ω)-nitro-L-arginine methyl ester (L-NAME)-sensitive superoxide production of aortic segments, reflective of eNOS uncoupling activity, was determined by electron spin resonance.

RESULTS

The L-NAME-sensitive superoxide production was more than doubled in wild-type diabetic mice, implicating uncoupling of eNOS. This was abolished in diabetic p47 ( phox-/-) (also known as Ncf1 (-/-)) mice, but preserved in Nox2 (-/y) (also known as Cybb (-/-)) mice made diabetic. The eNOS uncoupling activity was markedly attenuated in diabetic mice transfected with Nox1 or Nox1 organiser 1 (Noxo1) short interfering RNA (siRNA), and abolished in Nox1 (-/y) diabetic mice. Diabetes-induced impairment in endothelium-dependent vasorelaxation was also significantly attenuated in the Nox1 (-/y) mice made diabetic. By contrast, Nox4 siRNA, or inhibition of mitochondrial complex I or III with rotenone or siRNA, respectively, had no effect on diabetic uncoupling of eNOS. Overexpression of Dhfr, or oral administration of folic acid to improve dihydrofolate reductase (DHFR) function, recoupled eNOS in diabetes to improve endothelial function.

CONCLUSIONS/INTERPRETATION

Our data demonstrate for the first time that the p47(phox) and NOXO1-dependent activation of NOX1, but not that of NOX2, NOX4 or mitochondrion, mediates diabetic uncoupling of eNOS. NOX1-null mice are protected from diabetic endothelial dysfunction. Novel approaches to inhibit NOX1 and/or improve DHFR function, may prove to have therapeutic potential for diabetic endothelial dysfunction.

Adhesion-mediated cytoskeletal remodeling is controlled by the direct scaffolding of Src from FAK complexes to lipid rafts by SSeCKS/AKAP12

Metastatic cell migration and invasion are regulated by altered adhesion-mediated signaling to the actin-based cytoskeleton via activated Src-FAK complexes. SSeCKS (the rodent orthologue of human Gravin/AKAP12), whose expression is downregulated by oncogenic Src and in many human cancers, antagonizes oncogenic Src pathways including those driving neovascularization at metastatic sites, metastatic cell motility and invasiveness. This is likely manifested through its function as a scaffolder of F-actin and signaling proteins such as cyclins, calmodulin, protein kinase (PK) C and PKA. Here, we show that in contrast to its ability to inhibit haptotaxis, SSeCKS increased prostate cancer cell adhesion to fibronectin (FN) and type I collagen in a FAK-dependent manner, correlating with a relative increase in FAK^poY397 levels. In contrast, SSeCKS suppressed adhesion-induced Src activation (Src^poY416) and phosphorylation of FAK at Y925, a known Src substrate site. SSeCKS also induced increased cell spreading, cell flattening, integrin β1 clustering and formation of mature focal adhesion plaques. An in silico analysis identified a Src-binding domain on SSeCKS (a.a.153–166) that is homologous to the Src binding domain of Caveolin-1, and this region is required for SSeCKS-Src interaction, for SSeCKS-enhanced Src activity and sequestration to lipid rafts, and for SSeCKS-enhanced adhesion of MAT-LyLu and CWR22Rv1 prostate cancer cells. Our data suggest a model in which SSeCKS suppresses oncogenic motility by sequestering Src to caveolin-rich lipid rafts, thereby disengaging Src from FAK-associated adhesion and signaling complexes.