1,107 research outputs found

    The current status of radiological clinical audit and feedback on the ESR Guide to Clinical Audit in Radiology and the ESR Clinical Audit Tool (Esperanto) – an ESR Survey of European Radiology Departments

    Get PDF
    Clinical audit “according to national procedures” is a legal requirement as defined within the recently implemented European Council Basic Safety Standards Directive (BSSD), 2013/59/Euratom. A survey was undertaken in 2019 to assess the current status of clinical audit in European radiology departments and for feedback on the recently published “ESR Guide to Clinical Audit in Radiology” and the “ESR Clinical Audit Tool (Esperanto)”. The survey was distributed within the European Society of Radiology (ESR) EuroSafe Imaging Star network and also to European national radiological societies which are institutional members of the ESR

    Resveratrol reduces oxidative stress and cell death and increases mitochondrial antioxidants and XIAP in PC6.3-cells.

    Get PDF
    Resveratrol, a polyphenol derived e.g. from red grapes, has been shown to mediate several positive biological actions such as protection of cells against oxidative stress. It can also influence cell signaling, but the mechanisms behind its antioxidant properties are largely unknown. Here we show that RSV reduces oxidative stress and enhances cell survival in PC6.3 cells depending on the concentration. In these cells, RSV increased the levels of antioxidants, SOD2 and TRX2, and of X chromosome-linked inhibitor of apoptosis protein. RSV also activated NFκB signaling as shown using luciferase reporter constructs. These findings show that RSV regulates oxidative stress and mitochondrial antioxidants in neuronal cells. This may contribute to cell protection in various brain disorders

    New insights into the exploitation of vitis vinifera l. Cv. aglianico leaf extracts for nutraceutical purposes

    Get PDF
    The leaves of Vitis vinifera L. have been used for a long time in traditional medicine for the treatment of many ailments. Grape polyphenols, indeed, have been demonstrated to be able to defend against oxidative stress, responsible for various disorders such as cancer, diabetes and neurodegenerative diseases. The effects of different extraction techniques, Soxhlet (SOX), Accelerated Solvent (ASE 40, ASE 50) and Ultrasound Assisted Extraction (UAE) were studied in this work to evaluate their impact on the chemical profile and bioactive potential of Vitis vinifera L. (cv. Aglianico) leaf extracts. The phytochemical profile was investigated by HPLC-DAD and 9 phenolic compounds were identified and quantified in the extract. Moreover, the antioxidant, anticholinesterase and antityrosinase activities were evaluated. In detail, the total polyphenol content and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl, Oxygen Radical Absorbance Capacities and β-Carotene Bleaching assays) were evaluated and compared to assess the Relative Antioxidant Capacity Index (RACI). To test the inhibitory activity of extracts towards cholinesterases, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition assays were performed. SOX and ASE 50 have shown the highest value of RACI, 0.76 and 0.65, respectively. Regarding enzymatic inhibitory activity, ASE 50 (IC50 = 107.16 ± 8.12 µg/mL) and SOX (IC50 = 171.34 ± 12.12 µg/mL) extracts exhibited the highest AChE and BChE inhibitory activity, respectively, while UAE (IC50 = 293.2 ± 25.6 µg/mL, followed by SOX (IC50 = 302.5 ± 38.3 µg/mL) showed the highest tyrosinase inhibition value. Our results demonstrated for the first time that Aglianico leaves are important sources of phenols that could be used to prevent oxidative stress and be potentially helpful in diseases treatable with tyrosinase and cholinesterase inhibitors, like myasthenia gravis or Alzheimer’s

    identifying allosteric networks to fight antibiotics resistance

    Get PDF
    The rise of multi-drug resistance in bacterial pathogens is one of the grand challenges facing medical science. A major concern is the speed of development of β-lactamase-mediated resistance in Gram-negative species, thus putting at risk the efficacy of the most recently approved antibiotics and inhibitors, including carbapenems and avibactam, respectively. New strategies to overcome resistance are urgently required, which will ultimately be facilitated by a deeper understanding of the mechanisms that regulate the function of β-lactamases such as the Klebsiella Pneumoniae carbapenemases (KPCs). Using enhanced sampling computational methods together with site-directed mutagenesis, we report the identification of two “hydrophobic networks” in the KPC-2 enzyme, the integrity of which has been found to be essential for protein stability and corresponding resistance. Present throughout the structure, these networks are responsible for the structural integrity and allosteric signaling. Disruption of the networks leads to a loss of the KPC-2 mediated resistance phenotype, resulting in restored susceptibility to different classes of β-lactam antibiotics including carbapenems and cephalosporins. The ”hydrophobic networks” were found to be highly conserved among class-A β-lactamases, which implies their suitability for exploitation as a potential target for therapeutic intervention

    The GAPS Programme with HARPS-N@TNG IX. The multi-planet system KELT-6: detection of the planet KELT-6 c and measurement of the Rossiter-McLaughlin effect for KELT-6 b

    Get PDF
    Aims. For more than 1.5 years we monitored spectroscopically the star KELT-6 (BD+312447), known to host the transiting hot Saturn KELT-6b, because a previously observed long-term trend in radial velocity time series suggested the existence of an outer companion. Methods. We collected a total of 93 new spectra with the HARPS-N and TRES spectrographs. A spectroscopic transit of KELT-6b was observed with HARPS-N, and simultaneous photometry was obtained with the IAC-80 telescope. Results. We proved the existence of an outer planet with a mininum mass Mp_{\rm p}sini=3.71±\pm0.21 MJup_{\rm Jup} and a moderately eccentric orbit (e=0.210.036+0.039e=0.21_{-0.036}^{+0.039}) of period P\sim3.5 years. We improved the orbital solution of KELT-6b and obtained the first measurement of the Rossiter-McLaughlin effect, showing that the planet has a likely circular, prograde, and slightly misaligned orbit, with a projected spin-orbit angle λ\lambda=-36±\pm11 degrees. We improved the KELT-6b transit ephemeris from photometry, and we provided new measurements of the stellar parameters. KELT-6 appears as an interesting case to study the formation and evolution of multi-planet systems.Comment: Letter, 4 figures, accepted for publication in A&A. Some language editing and numbering of the paper series changed (from X to IX

    Neutral Iron Emission Lines From The Day-side Of KELT-9b -- The GAPS Programme With HARPS-N At TNG XX

    Get PDF
    We present the first detection of atomic emission lines from the atmosphere of an exoplanet. We detect neutral iron lines from the day-side of KELT-9b (Teq \sim 4, 000 K). We combined thousands of spectrally resolved lines observed during one night with the HARPS-N spectrograph (R \sim 115, 000), mounted at the Telescopio Nazionale Galileo. We introduce a novel statistical approach to extract the planetary parameters from the binary mask cross-correlation analysis. We also adapt the concept of contribution function to the context of high spectral resolution observations, to identify the location in the planetary atmosphere where the detected emission originates. The average planetary line profile intersected by a stellar G2 binary mask was found in emission with a contrast of 84 ±\pm 14 ppm relative to the planetary plus stellar continuum (40 ±\pm 5%\% relative to the planetary continuum only). This result unambiguously indicates the presence of an atmospheric thermal inversion. Finally, assuming a modelled temperature profile previously published (Lothringer et al. 2018), we show that an iron abundance consistent with a few times the stellar value explains the data well. In this scenario, the iron emission originates at the 10310^{-3}-10510^{-5} bar level.Comment: Accepted for publication on ApJL; 19 pages, 4 figures, 3 table

    The GAPS programme at TNG. XL. A puffy and warm Neptune-sized planet and an outer Neptune-mass candidate orbiting the solar-type star TOI-1422

    Get PDF
    Context. Neptunes represent one of the main types of exoplanets and have chemical-physical characteristics halfway between rocky and gas giant planets. Therefore, their characterization is important for understanding and constraining both the formation mechanisms and the evolution patterns of planets.Aims. We investigate the exoplanet candidate TOI-1422 b, which was discovered by the TESS space telescope around the high proper-motion G2 V star TOI-1422 (V = 10.6 mag), 155 pc away, with the primary goal of confirming its planetary nature and characterising its properties.Methods. We monitored TOI-1422 with the HARPS-N spectrograph for 1.5 yr to precisely quantify its radial velocity (RV) variation. We analyse these RV measurements jointly with TESS photometry and check for blended companions through high-spatial resolution images using the AstraLux instrument.Results. We estimate that the parent star has a radius of R star = 1.019(-0.013)( )(+0.014)R(circle dot), and a mass of M star = 0.981(-0.065)(+0.062) M-circle dot. Our analysis confirms the planetary nature of TOI-1422 b and also suggests the presence of a Neptune-mass planet on a more distant orbit, the candidate TOI-1422 c, which is not detected in TESS light curves. The inner planet, TOI-1422 b, orbits on a period of P-b = 12.9972 +/- 0.0006 days and has an equilibrium temperature of T-e(q,b) = 867 +/- 17 K. With a radius of R-b = 3.96(-0.11)(+0.1)(3) R-circle plus, a mass of M-b = 9.0(-2.0)(+2.3) M-circle plus and, consequently, a density of rho(b) = 0.795(-0.2)(35)( )(+0.290)g cm(-3), it can be considered a warm Neptune-sized planet. Compared to other exoplanets of a similar mass range, TOI-1422 b is among the most inflated, and we expect this planet to have an extensive gaseous envelope that surrounds a core with a mass fraction around 10% - 25% of the total mass of the planet. The outer non-transiting planet candidate, TOI-1422 c, has an orbital period of P-c = 29.29(-0.)(20)(+0.21) days, a minimum mass, M-c sin i, of 11.1(-2.3)(+2.6) M-circle plus, an equilibrium temperature of T-eq,T-c = 661 +/- 13 K and, therefore, if confirmed, could be considered as another warm Neptune

    Stereotactic reirradiation for local failure of brain metastases following previous radiosurgery: Systematic review and meta-analysis

    Get PDF
    Introduction: Local failure (LF) following stereotactic radiosurgery (SRS) of brain metastases (BM) may be treated with a second course of SRS (SRS2), though this procedure may increase the risk of symptomatic radionecrosis (RN). Methods: A literature search was conducted according to PRISMA to identify studies reporting LF, overall survival (OS) and RN rates following SRS2. Meta-analysis was performed to identify predictors of RN. Results: Analysis included 11 studies (335 patients,389 metastases). Pooled 1-year LF was 24 %(CI95 % 19–30 %): heterogeneity was acceptable (I2 = 21.4 %). Median pooled OS was 14 months (Confidence Interval 95 %, CI95 % 8.8–22.0 months). Cumulative crude RN rate was 13 % (95 %CI 8 %–19 %), with acceptable heterogeneity (I2 = 40.3 %). Subgroup analysis showed higher RN incidence in studies with median patient age ≥59 years (13 % [95 %CI 8 %–19 %] vs 7 %[95 %CI 3 %–12 %], p = 0.004) and lower incidence following prior Whole Brain Radiotherapy (WBRT, 19 %[95 %CI 13 %–25 %] vs 7%[95 %CI 3 %–13 %], p = 0.004). Conclusions: SRS2 is an effective strategy for in-site recurrence of BM previously treated with SRS
    corecore