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HL-2A plasmas heated by neutral beam injection (NBI) regularly exhibit n = 1 long-lived saturated magnetohydrodynamic instabilities. A reduction in the electron density and plasma stored energy and an increase in fast ion losses are usually observed in the presence of such perturbations. The observed long-lived saturated internal mode (LLM) occurs when the safety factor profile has a weak shear in a broad range of the plasma centre with qmin around unity. It is found that the ideal interchange mode can become marginally stable due to the weak magnetic shear reaching a critical value. The LLM, due to its pressure-driven feature, is destabilized by the strong interaction with fast ions in the low-shear region during the NBI. Furthermore, for the first time it is clearly observed that the LLMs can be suppressed by electron cyclotron resonant heating (ECRH), or by supersonic molecular beam injection in HL-2A plasmas. Low-n sidebands observed during the LLM are also suppressed by increasing the ECRH power. The control of LLMs is due to the change in the magnetic shear or in the pressure profile induced by the local heating or fuelling. [ABSTRACT FROM AUTHOR]

In this paper, we describe the behavior of impurity transport in the HL-2A electron cyclotron resonance heating (ECRH) L-mode plasma. The neon as a trace impurity is injected by the supersonic molecular beam injection (SMBI) technique, which is used for the first time to study the impurity transport in HL-2A. The progression of neon ions is monitored by the soft X-ray camera and bolometer arrays with good temporal and spatial resolutions. The convection and diffusion process of the neon ions are investigated with the one-dimensional impurity transport code STRAHL. The results show that the diffusion coefficient D of neon ions is a factor of four larger than the neoclassical value in the central region. The value of D is larger in the outer region of the plasma (ρ > 0.6) than in the central region of the plasma (ρ < 0.6). The convective velocity directs inwards with a value of ∼ −1.0 m/s in the Ohmic discharge, but it reverses to direct outwards with a value of ∼ 8.0 m/s in the outer region of the plasma when ECRH is applied. The result indicates that the impurity transport is strongly enhanced with ECRH. [ABSTRACT FROM AUTHOR]

Five new derivatives (2-6) were semi-synthesized using compound 1, a dihydro-ß-agarofuran sesquiterpene with C-2 ketone obtained from Parnassia wightiana, as the starting material by acylation, oxidation, reduction, esterification, and amination, respectively. Structures of 2-6 were confirmed by 1D- and 2D-NMR and HR-ESI-MS spectra. In addition, antifeedant activities of these compounds (1-6) were tested against the 3rd-instar larvae of Mythimna separata. Antifeedant effects of compounds 2 and 4 were greater than the parent compound 1 whereas other compounds exhibited low to no feeding deterrent effects against third instar M. separata larvae in lab bioassays. Therefore, our results suggest that acylated and reduced derivatives at C-8 and C-2, respectively, of 1 may improve the antifeeding effect. This preliminary information will be useful in designing new insect control agents against M. separata and other important pests. [ABSTRACT FROM AUTHOR]

The article offers an analysis of the chemical and biological literature that has appeared in the literature up to September 2012 regarding the isolation, structure elucidation, biological activities, biosynthesis, and chemical synthesis of azaphilone derivatives from nature. It demonstrates the structural and biological diversity of fungal polyketide azaphilones excreted from ascomycetous fungi.

The article discusses a study which describes the activity-guided isolation of antioxidant agents from tartary buckwheat bran (TBB). It informs that chemicals used in the study were obtained from Sigma AB. It mentions that TBB used in the study was the byproduct of flour processing using Chuanqiao 1, a type of buckwheat. The result of the study showed that all the tested extracts of TBB revealed antioxidant capacities and ethyl acetate fraction (EAF) had the highest antioxidant capacities.

Two tartary buckwheat samples (Xingku No.2 and Diqing) grown at three locations were analyzed for free and bound phenolic content and antioxidant properties. Moreover, the relative contributions of variety and growing environment to phenolic content and antioxidant properties were determined, as well as correlations of these properties to growing conditions. The total phenolic contents varied from 5,150 to 9,660 μmol of gallic acid equivalents per 100 gram of dry weight (DW) of tartary buckwheat and the free phenolics accounted for 94% to 99%. Rutin content was in the range from 518.54 to 1,447.87 mg per 100 gram of DW of tartary buckwheat. p-Hydroxybenzoic, ferulic and protocatechuic acids were the prominent phenolic acids and other phenolics, including p-coumaric, gallic, caffeic, vanillic and syringic acids were also detected. Tartary buckwheat exhibited higher DPPH• and ABTS•+ scavenging activities and was more effective at preventing the bleaching of β-carotene in comparison with reference antioxidant and plant phenolics constituents. Additionally, growing conditions and the interaction between variety and environment may have more contribution than variety to individual phenolics and antioxidant properties of tartary buckwheat. Environmental parameters such as higher altitudes may also have an increasing effect on rutin and phenolic acids. This study suggests that tartary buckwheat has potential health benefits because of its high phenolic content and antioxidant properties. These components could also be enhanced by optimizing the growing conditions of a selected variety. [ABSTRACT FROM AUTHOR]

new transmission-based Fourier transform infrared (FTIR) spectroscopic method for the direct determination of free fatty acids (FFA) in edible oils has been developed using the developed spectral reconstitution (SR) technique. Conventional neat-oil and SR calibrations were devised by spiking hexanoic acid into FFA-free canola oil and measuring the response to added FFA at 1,712 cm referenced to a baseline at 1,600 cm(1,712 cm/1,600 cm). To compensate for the known oil dependency of such calibration equations resulting from variation of the triacylglycerol ester (C═O) absorption with differences in oil saponification number (SN), a correction equation was devised by recording the spectra of blends of two FFA-free oils (canola and coconut) differing substantially in SN and correlating the intensity of the ester (C═O) absorption at the FFA measurement location with the intensity of the first overtone of this vibration, measured at 3,471 cm/3,427 cm. Further examination of the spectra of the oil blends by generalized 2D correlation spectroscopy revealed an additional strong correlation with an absorption in the near-infrared (NIR) combination band region, which led to the development of a second correction equation based on the absorbance at 4,258 cm/4,235 cm. The NIR-based correction equation yielded superior results and was shown to completely eliminate biases due to variations in oil SN, thereby making a single FFA calibration generally applicable to oils, regardless of SN. FTIR methodology incorporating this correction equation and employing the SR technique has been automated. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Sulfonated (SO3H-bearing) activated carbon (AC-SO3H) was synthesized by an aryl diazonium salt reduction process. The obtained material had a SO3H density of 0.64 mmol·g-1 and a specific surface area of 602 m±·g-1. The catalytic properties of ACSO3H were compared with that of two commercial solid acid catalysts, Nafion NR50 and Amberlyst-15. In a 10-h esterification reaction of acetic acid with ethanol, the acid conversion with AC-SO3H (78%) was lower than that of Amberlyst-15 (86%), which could be attributed to the fact that the SO3H density of the sulfonated carbon was lower than that of Amberlyst-15 (4.60 mmol·g-1). However, AC-SO3H exhibited comparable and even much higher catalytic activities than the commercial catalysts in the esterification of aliphatic acids with longer carbon chains such as hexanoic acid and decanoic acid, which may be due to the large specific surface area and mesoporous structures of the activated carbon. The disadvantage of AC-SO3H is the leaching of SO3H group during the reactions. [ABSTRACT FROM AUTHOR]

AbstractAim:To investigate the role of chemokine receptor CXCR3 in cigarette smoking (CS)-induced pulmonary damage.Methods:CXCR3 knockout (CXCR3-/-) mice were used. Differences in airspace enlargement, mRNA expression of matrix metalloproteinases (MMPs), transforming growth factor (TGF) β1, CXCL10 in lung homogenates, and CXCL10 content in bronchoalveolar lavage (BAL) fluids and homogenates were compared between CXCR3-/- mice and wild-type (WT) mice three days after three-day CS exposures.Results:The linear intercept was significantly less in CXCR3-/- mice than in WT mice (30.1±0.9 μm vs 40.3±2.4 μm, P<0.01). Morphologically, collagen was deposited less around airways and vessels in CXCR3-/- mice. The lung hydroxyproline content was significantly lower in CXCR3-/- mice than in WT mice (6.0±1.0 μg/mL vs 12.0±1.6 μg/mL, P<0.05). Profoundly lower mRNA expression of MMP2, MMP12, TGFβ1, and CXCL10 was seen in lung homogenates from CXCR3-/- mice. CXCL10 concentrations in BAL fluid and lung homogenates were significantly lower in CXCR3-/- mice than in WT mice (BAL fluid: 19.3±1.4 pg/mL vs 24.8±1.6 pg/mL, P<0.05; lung homogenates: 76.6±7.0 pg/mL vs 119.5±15.9 pg/mL, P<0.05).Conclusion:CXCR3 is important in mediating lung tissue damage and airway remodeling following a short-term CS insult, possibly through up-regulation of CXCL10 and inducement of mRNA expression of MMPs. Targeting CXCR3 may be helpful for prevention of CS-induced pulmonary pathology. [ABSTRACT FROM AUTHOR]

Automated software was developed to analyze the molecular formula of organic molecules and peptides based on high-resolution MS/MS spectroscopic data. The software was validated with 96 compounds including a few small peptides in the mass range of 138–1569 Da containing the elements carbon, hydrogen, nitrogen and oxygen. A Micromass Waters Q-TOF Ultima Global mass spectrometer was used to measure the molecular masses of precursor and fragment ions. Our software assigned correct molecular formulas for 91 compounds, incorrect molecular formulas for 3 compounds, and no molecular formula for 2 compounds. The obtained 95% success rate indicates high reliability of the software. The mass accuracy of the precursor ion and the fragment ions, which is critical for the success of the analysis, was high, i.e.the accuracy and the precision of 850 data were 0.0012 Da and 0.0016 Da, respectively. For the precursor and fragment ions below 500 Da, 60% and 90% of the data showed accuracy within ≤0.001 Da and ≤0.002 Da, respectively. The precursor and fragment ions above 500 Da showed slightly lower accuracy, i.e.40% and 70% of them showed accuracy within ≤0.001 Da and ≤0.002 Da, respectively. The molecular formulas of the precursor and the fragments were further used to analyze possible mass spectrometric fragmentation pathways, which would be a powerful tool in structural analysis and identification of small molecules. The method is valuable in the rapid screening and identification of small molecules such as the dereplication of natural products, characterization of drug metabolites, and identification of small peptide fragments in proteomics. The analysis was also extended to compounds that contain a chlorine or bromine atom. [ABSTRACT FROM AUTHOR]

Aim:Human CXCR3, a seven-transmembrane segment (7TMS), is predominantly expressed in Th1-mediated responses. Interferon-γ-inducible protein 10 (IP-10) is an important ligand for CXCR3. Their interaction is pivotal for leukocyte migration and activation. Tyrosine sulfation in 7TMS is a posttranslational modification that contributes substantially to ligand binding. We aimed to study the role of tyrosine sulfation of CXCR3 in the protein's binding to IP-10.Methods:Plasmids encoding CXCR3 and its mutants were prepared by PCR and site-directed mutagenesis. HEK 293T cells were transfected with plasmids encoding CXCR3 or its variants using calcium phosphate. Transfected cells were labeled with [35S]-cysteine and methionine or [35S]-Na2SO3 and then analyzed by immunoprecipitation to measure sulfation. Experiments with 125I-labeled IP-10 were carried out to evaluate the affinity of CXCR3 for its ligand. Calcium influx assays were used to measure intercellular signal transduction.Results:Our data show that sulfate moieties are added to tyrosines 27 and 29 of CXCR3. Mutation of these two tyrosines to phenylalanines substantially decreases binding of CXCR3 to IP-10 and appears to eliminate the associated signal transduction. Tyrosine sulfation of CXCR3 is enhanced by tyrosyl protein sulfotransferases (TPSTs), and it is weakened by shRNA constructs. The binding ability of CXCR3 to IP-10 is increased by TPSTs and decreased by shRNAs.Conclusions:This study identifies two sulfated tyrosines in the N-terminus of CXCR3 as part of the binding site for IP-10, and it underscores the fact that tyrosine sulfation in the N-termini of 7TMS receptors is functionally important for ligand interactions. Our study suggests a molecular target for inhibiting this ligand-receptor interaction.Acta Pharmacologica Sinica (2009) 30: 193–201; doi: 10.1038/aps.2008.24; published online 19th January 2009 [ABSTRACT FROM AUTHOR]

Aim: CXCR3, via binding its specific ligand CXCL10, plays an important role in cigarette smoke (CS)-induced pulmonary inflammation. CXCR3 is preferentially expressed in activated T cells (chiefly CD8+ T cells). The purpose of this study was to investigate the role of CXCR3 in CS-induced pulmonary injury using CXCR3 gene-deficient (CXCR3−/−) mice. Methods: Differences in the infiltration of inflammatory cells and CD8+ T cells and the expression of inflammatory mediators and chemokines in the bronchoalveolar lavage fluid and lungs at the mRNA and protein levels were compared between CXCR3−/− mice and wild-type (WT) mice at 2 h after 3 d of CS exposure. Results: Compared with their WT counterparts, the CXCR3−/− mice showed alleviated inflammation, as evidenced by fewer inflammatory cells, particularly cytotoxic CD8+ T cells, in bronchoalveolar lavage fluid and lung tissues. At both the mRNA and protein levels, there were significantly lower levels of inflammatory and chemotactic cytokines, including TNF-α, interleukin-8, interferon-γ, transforming growth factor-β1, and CXCL10 in the CXCR3−/− mice. Conclusion: Our data show that CXCR3 is important in recruiting inflammatory cells (particularly CD8+ T cells) into the airways and lungs, as well as initiating inflammatory and fibrotic cytokines release at 2 h following a short-term CS insult. CXCR3 could be a novel target for the treatment of pulmonary inflammation induced by CS. [ABSTRACT FROM AUTHOR]

A new triterpene, taraxast-20(30)-en-3 β,12 β-diol ( 1), and eight known compounds were isolated from the leaves of Craibiodendron yunnanense. Their structures were established on the basis of spectral evidence. [ABSTRACT FROM AUTHOR]

Covering: January 1990 to June 2006 [ABSTRACT FROM AUTHOR]

The article presents a study that investigates the new bioactive substance produced by endophytic fungus alternaria alternata from Maytenus hookeri. The research was conducted by measuring mass spectra of the leaves of Maytenus hookeri collected in China using VG Auto spec-3000 spectrometer and Thermo Finnigan LCQ Advantage wherein the fungus was cultured using a liquid medium and was filtered, isolated and fermented. The infrared spectrum was able to assert the presence of unsaturated aldehyde and ketone and the strains of alternaria were capable of producing a variety of secondary metabolites that are phytotoxic.

The article discusses the isolation and structure elucidation of nine compounds including uridine and adenosine from the endophytic fungus Alternaria alternata of Maytenus hookeri or Celastraceae. It states that these compounds were afforded through further separation of methanol and petroleum ether, ethyl acetate methanol acetic acid extract of A. alternata. It used column chromatography and preparative thin layer chromatography (TLC) on silicon gel and Sephadex LH-20 and reversed-phase RP-18.

A minor novel 1,7-naphthyridine alkaloid with an unprecedented skeleton, named anisopusine (1), was isolated from the CH2Cl2 soluble materials of an acetone extract of the bark of Anisopus mannii (Asclepiadaceae) together with four known compounds 5α-hydroxy-lup-20(29)-en-3β-yl eicosanoate (2), [6]-gingerdione (3), [6]-dehydrogingerdione (4), and ferulic acid (5). Their structures were determined on the basis of spectroscopic data, including 1D and 2D NMR, HR-EI-MS. Compounds (2–5) were characterized for the first time from this genus. Dans les matériaux solubles dans le CH2Cl2, obtenus à partir des produits solides obtenus par extraction de l’écorce d’Anisopus mannii (asclépiadacée) avec de l’acétone, on a isolé un nouvel alcaloïde mineur dont la structure comporte un squelette inconnu jusqu’à maintenant, une 1,7-naphtypyridine, et qui a été dénommé anisopusine (1); à ses côtés, on a aussi retrouvé quatre produits connus, l’eiconinate de 5α-hydroxylup-20(29)-én-3β-yle (2), la [6]-gingerdione (3), la [6]-déhydrogingerdione (4) et l’acide férulique (5). Les structures ont été déterminées sur la base de données spectroscopiques, dont la RMN en 1D et 2D et la spectrométrie de masse à ionisation électronique à haute résolution (SM-IE-HR). La caractérisation des composés 2 à 5 dans ce gène est une première. [ABSTRACT FROM AUTHOR]

The ELMy H-mode plasmas realized with the supersonic molecular beam injection (SMBI) are studied in relation to the energy confinement and the heating power for the L–H transition ( in the HL-2A tokamak. A database is assembled for this study based on the ELMy H-mode discharges during the experimental campaigns in the period 2009–2013 at the HL-2A tokamak. The statistical results show that the SMBI is favourable for reaching the H-mode by reducing the heating power at the L–H transition and for the H-mode performance by improving the energy confinement compared with the ordinary gas puffing (GP). The reduction of is about 20% when the density is low, and the energy confinement enhancement factor of 1.5 is achieved with the SMBI. Note that in the database the density dependence of is non-monotonic with the at which the is minimum. Most of data are on the low density branch where the increases with the decrease in density. The minimum of the in HL-2A is comparable to the ITPA multi-machine threshold power scaling . The physics behind the reduction of the with the SMBI is also investigated in relation to the change of the density gradient at the plasma edge, the gas fuelling efficiency, and the recycling. [ABSTRACT FROM AUTHOR]

The article provides information on the study concerning the bioactive ergosterol derivatives which are isolated from the basidiomycete fungus Lactarius hatsudake in China. The author implies that the fruiting bodies of Lactarius hatsudake have long been utilized as antitumor and antiviral agents in Chinese folk medicine.