799 research outputs found
Barley beta-glucan promotes MnSOD expression and enhances angiogenesis under oxidative microenvironment
Manganese superoxide dismutase (MnSOD), a foremost antioxidant enzyme, plays a key role in angiogenesis. Barley-derived (1.3) β-d-glucan (β-d-glucan) is a natural water-soluble polysaccharide with antioxidant properties. To explore the effects of β-d-glucan on MnSOD-related angiogenesis under oxidative stress, we tested epigenetic mechanisms underlying modulation of MnSOD level in human umbilical vein endothelial cells (HUVECs) and angiogenesis in vitro and in vivo. Long-term treatment of HUVECs with 3% w/v β-d-glucan significantly increased the level of MnSOD by 200% ± 2% compared to control and by 50% ± 4% compared to untreated H2O2-stressed cells. β-d-glucan-treated HUVECs displayed greater angiogenic ability. In vivo, 24 hrs-treatment with 3% w/v β-d-glucan rescued vasculogenesis in Tg (kdrl: EGFP) s843Tg zebrafish embryos exposed to oxidative microenvironment. HUVECs overexpressing MnSOD demonstrated an increased activity of endothelial nitric oxide synthase (eNOS), reduced load of superoxide anion (O2-) and an increased survival under oxidative stress. In addition, β-d-glucan prevented the rise of hypoxia inducible factor (HIF)1-α under oxidative stress. The level of histone H4 acetylation was significantly increased by β-d-glucan. Increasing histone acetylation by sodium butyrate, an inhibitor of class I histone deacetylases (HDACs I), did not activate MnSOD-related angiogenesis and did not impair β-d-glucan effects. In conclusion, 3% w/v β-d-glucan activates endothelial expression of MnSOD independent of histone acetylation level, thereby leading to adequate removal of O2-, cell survival and angiogenic response to oxidative stress. The identification of dietary β-d-glucan as activator of MnSOD-related angiogenesis might lead to the development of nutritional approaches for the prevention of ischemic remodelling and heart failure
Human herpesvirus 8-associated primary effusion lymphoma in human immunodeficiency virus-negative patients: a clinico-epidemiologic variant resembling classic Kaposi's sarcoma
No abstract availabl
A-PHOT: a new, versatile code for precision aperture photometry
We present A-PHOT, a new publicly available code for performing aperture
photometry on astronomical images, that is particularly well suited for
multi-band extragalactic surveys. A-PHOT estimates the fluxes emitted by
astronomical objects within a chosen set of circular or elliptical apertures.
Unlike other widely used codes, it runs on predefined lists of positions,
allowing for repeated measurements on the same list of objects on different
images. This can be very useful when forced photometric measurement on a given
position is needed. A-PHOT can also estimate morphological parameters and a
local background flux, and compute on-the-fly individual optimized elliptical
apertures, in which the signal-to-noise ratio is maximized. We check the
performance of A-PHOT on both synthetic and real test datasets: we explore a
simulated case of a space-based high-resolution imaging dataset, investigating
the input parameter space to optimize the accuracy of the performance, and we
exploit the CANDELS GOODS-South data to compare the A-PHOT measurements with
those from the survey legacy catalogs, finding good agreement overall. A-PHOT
proves to a useful and versatile tool for quickly extracting robust and
accurate photometric measurements and basic morphological information of
galaxies and stars, with the advantage of allowing for various measurements of
fluxes at any chosen position without the need of a full detection run, and for
determining the basic morphological features of the sources.Comment: 10 pages, 9 figure
K-edge X-ray absorption spectra in transition metal oxides beyond the single particle approximation: shake-up many body effects
The near edge structure (XANES) in K-edge X-ray absorption spectroscopy (XAS)
is a widely used tool for studying electronic and local structure in materials.
The precise interpretation of these spectra with the help of calculations is
hence of prime importance, especially for the study of correlated materials
which have a complicated electronic structure per se. The single particle
approach, for example, has generally limited itself to the dominant dipolar
cross-section. It has long been known however that effects beyond this approach
should be taken into account, both due to the inadequacy of such calculations
when compared to experiment and the presence of shake-up many-body satellites
in core-level photoemission spectra of correlated materials. This effect should
manifest itself in XANES spectra and the question is firstly how to account for
it theoretically and secondly how to verify it experimentally. By using
state-of-the-art first principles electronic structure calculations and 1s
photoemission measurements we demonstrate that shake-up many-body effects are
present in K-edge XAS dipolar spectra of NiO, CoO and CuO at all energy scales.
We show that shake-up effects can be included in K-edge XAS spectra in a simple
way by convoluting the single-particle first-principles calculations including
core-hole effects with the 1s photoemission spectra. We thus describe all
features appearing in the XAS dipolar cross-section of NiO and CoO and obtain a
dramatic improvement with respect to the single-particle calculation in CuO.
These materials being prototype correlated magnetic oxides, our work points to
the presence of shake-up effects in K-edge XANES of most correlated transition
metal compounds and shows how to account for them, paving the way to a precise
understanding of their electronic structure.Comment: 6 pages, 4 picture
Design principles for the future internet architecture
Design principles play a central role in the architecture of the Internet as driving most engineering decisions at conception level and operational level. This paper is based on the EC Future Internet Architecture (FIArch) Group results and identifies some of the design principles that we expect to govern the future architecture of the Internet. We believe that it may serve as a starting point and comparison for most research and development projects that target the so-called Future Internet Architecture
Enhanced Optical 13C Hyperpolarization in Diamond Treated by High-Temperature Rapid Thermal Annealing
Methods of optical dynamic nuclear polarization open the door to the replenishable hyperpolarization of nuclear spins, boosting their nuclear magnetic resonance/imaging signatures by orders of magnitude. Nanodiamond powder rich in negatively charged nitrogen vacancy defect centers has recently emerged as one such promising platform, wherein 13C nuclei can be hyperpolarized through the optically pumped defects completely at room temperature. Given the compelling possibility of relaying this 13C polarization to nuclei in external liquids, there is an urgent need for the engineered production of highly “hyperpolarizable” diamond particles. Here, a systematic study of various material dimensions affecting optical 13C hyperpolarization in diamond particles is reported on. It is discovered surprisingly that diamond annealing at elevated temperatures ∼1720 °C has remarkable effects on the hyperpolarization levels enhancing them by above an order of magnitude over materials annealed through conventional means. It is demonstrated these gains arise from a simultaneous improvement in NV− electron relaxation/coherence times, as well as the reduction of paramagnetic content, and an increase in 13C relaxation lifetimes. This work suggests methods for the guided materials production of fluorescent, 13C hyperpolarized, nanodiamonds and pathways for their use as multimodal (optical and magnetic resonance) imaging and hyperpolarization agents
High efficacy of onabotulinumtoxinA treatment in patients with comorbid migraine and depression: a meta-analysis
Background: Migraine and depression are highly prevalent and partly overlapping disorders that cause strong limitations in daily life. Patients tend to respond poorly to the therapies available for these diseases. OnabotulinumtoxinA has been proven to be an effective treatment for both migraine and depression. While many studies have addressed the effect of onabotulinumtoxinA in migraine or depression separately, a growing body of evidence suggests beneficial effects also for patients comorbid with migraine and depression. The current meta-analysis systematically investigates to what extent onabotulinumtoxinA is efficient in migraineurs with depression. Methods: A systematic literature search was performed based on PubMed, Scopus and Web of Science from the earliest date till October 30 th, 2020. Mean, standard deviation (SD) and sample size have been used to evaluate improvement in depressive symptoms and migraine using random-effects empirical Bayes model. Results: Our search retrieved 259 studies, eight of which met the inclusion criteria. OnabotulinumtoxinA injections administered to patients with both chronic migraine and major depressive disorder led to mean reduction of -8.94 points (CI [-10.04,-7.84], p < 0.01) in the BDI scale, of -5.90 points (CI [-9.92,-1.88], p < 0.01) in the BDI-II scale and of -6.19 points (CI [-9.52,-2.86], p < 0.01) in the PHQ-9 scale, when evaluating depressive symptoms. In the case of the migraine-related symptoms, we found mean reductions of -4.10 (CI [-7.31,-0.89], p = 0.01) points in the HIT6 scale, -32.05 (CI [-55.96,-8.14], p = 0.01) in the MIDAS scale, -1.7 (CI [-3.27,-0.13], p = 0.03) points in the VAS scale and of -6.27 (CI [-8.48,-4.07], p < 0.01) migraine episodes per month. Comorbid patients showed slightly better improvements in BDI, HIT6 scores and migraine frequency compared to monomorbid patients. The latter group manifested better results in MIDAS and VAS scores. Conclusion: Treatment with onabotulinumtoxinA leads to a significant reduction of disease severity of both chronic migraine and major depressive disorder in patients comorbid with both diseases. Comparative analyses suggest an equivalent strong effect in monomorbid and comorbid patients, with beneficial effects specifically seen for certain migraine features
Decay Constants of Heavy-Light Mesons
The decay constants of the heavy-light pseudoscalar mesons are studied in a
high statistics run using the Wilson action at and , and
the clover action at . The systematics of discretisation
errors are discussed. Our best estimates of the decay constants are: =
218(9) MeV, = 1.11(1) and we obtain preliminary values for .Comment: at the Dallas Lattice Conference, October 1993. 3 pages in a single
postscript file, uuencoded form. Rome Preprint 93/98
- …