Measurement of D* Meson Cross Sections at HERA and Determination of the Gluon Density in the Proton using NLO QCD

With the H1 detector at the ep collider HERA, D* meson production cross sections have been measured in deep inelastic scattering with four-momentum transfers Q^2>2 GeV2 and in photoproduction at energies around W(gamma p)~ 88 GeV and 194 GeV. Next-to-Leading Order QCD calculations are found to describe the differential cross sections within theoretical and experimental uncertainties. Using these calculations, the NLO gluon momentum distribution in the proton, x_g g(x_g), has been extracted in the momentum fraction range 7.5x10^{-4}< x_g <4x10^{-2} at average scales mu^2 =25 to 50 GeV2. The gluon momentum fraction x_g has been obtained from the measured kinematics of the scattered electron and the D* meson in the final state. The results compare well with the gluon distribution obtained from the analysis of scaling violations of the proton structure function F_2.Comment: 27 pages, 9 figures, 2 tables, submitted to Nucl. Phys.

Investigating the inclusion properties of aromatic amino acids complexing beta-cyclodextrins in model peptides

Cyclodextrins are commonly used as complexing agents in biological, pharmaceutical, and industrial applications since they have an effect on protein thermal and proteolytic stability, refolding yields, solubility, and taste masking. β-cyclodextrins (β-CD), because of their cavity size are a perfectly suited complexing agent for many common guest moieties. In the case of peptide-cyclodextrin and protein-cyclodextrin host-guest complexes the aromatic amino acids are reported to be the principal responsible of the interaction. For these reasons, we have investigated the inclusion properties of nine designed tripeptides, obtained permuting the position of two l-alanines (Ala, A) with that of one l-tryptophan (Trp, W), l-phenylalanine (Phe, F), or l-tyrosine (Tyr, Y), respectively. Interestingly, the position of the aromatic side-chain in the sequence appears to modulate the β-CD:peptide binding constants, determined via UV-Vis and NMR spectroscopy, which in turn assumes values higher than those reported for the single amino acid. The tripeptides containing a tyrosine showed the highest binding constants, with the central position in the Ac-AYA-NH2 peptide becoming the most favorite for the interaction. A combined NMR and Molecular Docking approach permitted to build detailed complex models, highlighting the stabilizing interactions of the neighboring amino acids backbone atoms with the upper rim of the β-CD

Insight into the structural and functional features of myoglobin from Hystrix cristata L. and Rangifer tarandus L.

The amino acid sequence, structural and functional features of two novel myoglobins (Mbs) isolated from a crested porcupine (Hystrix cristata L.) and reindeer (Rangifer tarandus L.) were determined. The primary structure was achieved by using a combined approach based on de novo sequencing by ESI-Q-TOF MS/MS and peptide mapping by MALDI-TOF MS. This strategy allowed us to determine the primary structure of crested porcupine and reindeer Mbs. To go deeper, 3D modeling studies followed by structural characterization by NMR on both myoglobins demonstrate that reindeer Mb shows slightly different orientation of F, G and H a-helices. As a consequence, reindeer Mb may differently modulate the heme environment, facilitating oxygenation as well as ensuring that the heme iron remains in a ferrous state. Finally, reindeer Mb shows a less stable conformation with respect to crested porcupine Mb (Tm 353.7 K vs. Tm 356.3 K, respectively).The amino acid sequence, structural and functional features of two novel myoglobins (Mbs) isolated from a crested porcupine (Hystrix cristata L.) and reindeer (Rangifer tarandus L.) were determined. The primary structure was achieved by using a combined approach based on de novo sequencing by ESI-Q-TOF MS/MS and peptide mapping by MALDI-TOF MS. This strategy allowed us to determine the primary structure of crested porcupine and reindeer Mbs. To go deeper, 3D modeling studies followed by structural characterization by NMR on both myoglobins demonstrate that reindeer Mb shows slightly different orientation of F, G and H a-helices. As a consequence, reindeer Mb may differently modulate the heme environment, facilitating oxygenation as well as ensuring that the heme iron remains in a ferrous state. Finally, reindeer Mb shows a less stable conformation with respect to crested porcupine Mb (Tm 353.7 K vs. Tm 356.3 K, respectively)

Coenzyme Q10, Rosuvastatin, and Clinical Outcomes in Heart FailureA Pre-Specified Substudy of CORONA (Controlled Rosuvastatin Multinational Study in Heart Failure)

Objectives The purpose of this study was to determine whether coenzyme Q(10) is an independent predictor of prognosis in heart failure. Background Blood and tissue concentrations of the essential cofactor coenzyme Q(10) are decreased by statins, and this could be harmful in patients with heart failure. Methods We measured serum coenzyme Q(10) in 1,191 patients with ischemic systolic heart failure enrolled in CORONA (Controlled Rosuvastatin Multinational Study in Heart Failure) and related this to clinical outcomes. Results Patients with lower coenzyme Q(10) concentrations were older and had more advanced heart failure. Mortality was significantly higher among patients in the lowest compared to the highest coenzyme Q(10) tertile in a univariate analysis (hazard ratio: 1.50, 95% confidence interval: 1.04 to 2.6, p = 0.03) but not in a multivariable analysis. Coenzyme Q(10) was not an independent predictor of any other clinical outcome. Rosuvastatin reduced coenzyme Q(10) but there was no interaction between coenzyme Q(10) and the effect of rosuvastatin. Conclusions Coenzyme Q(10) is not an independent prognostic variable in heart failure. Rosuvastatin reduced coenzyme Q(10), but even in patients with a low baseline coenzyme Q(10), rosuvastatin treatment was not associated with a significantly worse outcome

Effectiveness of the combination elvitegravir/cobicistat/tenofovir/emtricitabine (EVG/COB/TFV/FTC) plus darunavir among treatment-experienced patients in clinical practice : A multicentre cohort study

Background: The aim of this study was to investigate the effectiveness and tolerability of the combination elvitegravir/cobicistat/tenofovir/emtricitabine plus darunavir (EVG/COB/TFV/FTC + DRV) in treatment-experienced patients from the cohort of the Spanish HIV/AIDS Research Network (CoRIS). Methods: Treatment-experienced patients starting treatment with EVG/COB/TFV/FTC + DRV during the years 2014-2018 and with more than 24 weeks of follow-up were included. TFV could be administered either as tenofovir disoproxil fumarate or tenofovir alafenamide. We evaluated virological response, defined as viral load (VL) < 50 copies/ml and < 200 copies/ml at 24 and 48 weeks after starting this regimen, stratified by baseline VL (< 50 or ≥ 50 copies/ml at the start of the regimen). Results: We included 39 patients (12.8% women). At baseline, 10 (25.6%) patients had VL < 50 copies/ml and 29 (74.4%) had ≥ 50 copies/ml. Among patients with baseline VL < 50 copies/ml, 85.7% and 80.0% had VL < 50 copies/ml at 24 and 48 weeks, respectively, and 100% had VL < 200 copies/ml at 24 and 48 weeks. Among patients with baseline VL ≥ 50 copies/ml, 42.3% and 40.9% had VL < 50 copies/ml and 69.2% and 68.2% had VL < 200 copies/ml at 24 and 48 weeks. During the first 48 weeks, no patients changed their treatment due to toxicity, and 4 patients (all with baseline VL ≥ 50 copies/ml) changed due to virological failure. Conclusions: EVG/COB/TFV/FTC + DRV was well tolerated and effective in treatment-experienced patients with undetectable viral load as a simplification strategy, allowing once-daily, two-pill regimen with three antiretroviral drug classes. Effectiveness was low in patients with detectable viral loads