4,351 research outputs found

    Simultaneous VLBI Astrometry of H2O and SiO Masers toward the Semiregular Variable R Crateris

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    We obtained, for the first time, astrometrically registered maps of the 22.2 GHz H2O and 42.8, 43.1, and 86.2 GHz SiO maser emission toward the semiregular b-type variable (SRb) R Crateris, at three epochs (2015 May 21, and 2016 January 7 and 26) using the Korean Very-long-baseline Interferometry Network. The SiO masers show a ring-like spatial structure, while the H2O maser shows a very asymmetric one-side outflow structure, which is located at the southern part of the ring-like SiO maser feature. We also found that the 86.2 GHz SiO maser spots are distributed in an inner region, compared to those of the 43.1 GHz SiO maser, which is different from all previously known distributions of the 86.2 GHz SiO masers in variable stars. The different distribution of the 86.2 GHz SiO maser seems to be related to the complex dynamics caused by the overtone pulsation mode of the SRb R Crateris. Furthermore, we estimated the position of the central star based on the ring fitting of the SiO masers, which is essential for interpreting the morphology and kinematics of a circumstellar envelope. The estimated stellar coordinate corresponds well to the position measured by Gaia

    Selection of high berberine yielding phellodendron insulare nak. lines and the antimicrobial activity of their extracts

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    High berberine yielding Phellodendron insulare Nak. lines were selected by aggregate cloning method and the antimicrobial activity of their extracts was assessed. The berberine producing cork tree lines were selected by adopting a colorimetric method. In all 300 high berberine producing lines were selected with a colorimetric reagent containing 5M HCl and H2O2 and established from dissociated cell aggregates. The crude extracts from these lines showed antibacterial activities against tested Escherichia coli, Staphylococcus aureus, Salmonella typhimulium, and Listeria monocytogenes. The cork tree extracts were found to be inhibitory to these test organisms. Further the antimicrobial activity of plant extracts was on par with the berberine isolated from the extracts from native cork trees. These results have potential for developing alternative plant products as antimicrobial substances for application in agriculture and food industry

    Non-Invasive Follow-up Evaluation of Post-Embolized AVM with Time-Resolved MRA: A Case Report

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    We report the hemodynamic assessment in a patient with cerebral arteriovenous malformation using time-resolved magnetic resonance angiography (TR-MRA), a non-invasive modality, and catheter-based digital subtraction angiography (DSA), before and after embolization. Comparison of the results showed that TR-MRA produced very fast dynamic images and the findings closely matched those obtained at DSA. For initial work-up and follow-up studies in patients with vascular lesions, TR-MRA and DSA are therefore comparable

    Bee venom attenuates neuroinflammatory events and extends survival in amyotrophic lateral sclerosis models

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    <p>Abstract</p> <p>Background</p> <p>Amyotrophic lateral sclerosis (ALS) is a disease affecting the central nervous system that is either sporadic or familial origin and causing the death of motor neurons. One of the genetic factors contributing to the etiology of ALS is mutant SOD1 (mtSOD1), which induces vulnerability of motor neurons through protein misfolding, mitochondrial dysfunction, oxidative damage, cytoskeletal abnormalities, defective axonal transport, glutamate excitotoxicity, inadequate growth factor signaling, and neuroinflammation. Bee venom has been used in the practice of Oriental medicine and evidence from the literature indicates that BV plays an anti-inflammatory or anti-nociceptive role against inflammatory reactions associated with arthritis and other inflammatory diseases. The purpose of the present study was to determine whether bee venom suppresses motor neuron loss and microglial cell activation in hSOD1<sup>G93A </sup>mutant mice.</p> <p>Methods</p> <p>Bee venom (BV) was bilaterally injected (subcutaneously) into a 14-week-old (98 day old) male hSOD1<sup>G93A </sup>animal model at the Zusanli (ST36) acupoint, which is known to mediate an anti-inflammatory effect. For measurement of motor activity, rotarod test was performed and survival statistics were analyzed by Kaplan-Meier survival curves. The effects of BV treatment on anti-neuroinflammation of hSOD1<sup>G93A </sup>mice were assessed via immunoreactions using Iba 1 as a microglia marker and TNF-Ī± antibody. Activation of ERK, Akt, p38 MAP Kinase (MAPK), and caspase 3 proteins was evaluated by western blotting.</p> <p>Results</p> <p>BV-treated mutant hSOD1 transgenic mice showed a decrease in the expression levels of microglia marker and phospho-p38 MAPK in the spinal cord and brainstem. Interestingly, treatment of BV in symptomatic ALS animals improved motor activity and the median survival of the BV-treated group (139 Ā± 3.5 days) was 18% greater than control group (117 Ā± 3.1 days). Furthermore, we found that BV suppressed caspase-3 activity and blocked the defects of mitochondrial structure and cristae morphology in the lumbar spinal cord of hSOD1<sup>G93A </sup>mice at the symptomatic stage.</p> <p>Conclusion</p> <p>From these findings, our research suggests BV could be a potential therapeutic agent for anti-neuroinflammatory effects in an animal model of ALS.</p

    Catalytic Performance for Hydrocarbon Production from Syngas on the Promoted Co-Based Hybrid Catalysts; Influence of Pt Contents

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    Fischer-Tropsch synthesis (FTS) reaction from syngas was investigated on the Pt-promoted cobalt-based hybrid catalysts prepared by co-precipitation method in a slurry of ZSM-5 (Si/Al=25). The hybrid catalysts were compared with each other for the different content of Pt as a promoter and are characterized using BET, XRD, H2-TPR and NH3-TPD. Their physicochemical properties were correlated with the activity and selectivity of the catalysts. As results, all hybrid catalysts show the C5-C9 yield (%) higher than that of Co-Al2O3/ZSM-5 catalyst. The Pt-promoted hybrid catalysts were found to be more promising towards production of the hydrocarbons of gasoline range and over C10.

    Potassium chloride elicits enhancement of bilobalide and Ginkgolides production by Ginkgo biloba cell cultures

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    This study investigated the ability of potassium chloride (KCl) to elicit the production of bilobalide (BB), ginkgolide A (GA) and ginkgolide B (GB) by Ginkgo biloba cell suspension cultures. The salt stress by KCl treatments increased production of BB, GA and GB in both suspended cells and cultured medium. Especially, treatment of KCl 800 mM of highest concentration was stimulated emission into cultured medium BB, GA and GB compounds accumulated in cells. Although KCl 800 mM severely inhibited cells growth, the maximum content of GA and GB in cells was obtained in the treatment of KCl 800 mM, which was 1.9 and 4.0 times higher than the control. These results thus suggest that salt stress can afford enhanced production of secondary metabolites by plant cell cultures
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