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Context. Dual-field interferometric observations with VLTI/GRAVITY sometimes require the use of a binary calibrator. This is a binary star whose individual components remain unresolved by the interferometer, with a separation between 400 and 2000 mas for observations with the Unit Telescopes (UTs), or 1200–3000 mas for the Auxiliary Telescopes (ATs). The separation vector also needs to be predictable to within 10 mas for a proper pointing of the instrument. Aims. No list of properly vetted calibrators was available so far for dual-field observations with VLTI/GRAVITY on the UTs. Our objective is to compile such a list and make it available to the community. Methods. We identified a list of candidates from the Washington Double Star (WDS) catalogue, all with appropriate separations and brightness, scattered over the southern sky. We observed them as part of a dedicated calibration programme, determined whether these objects were true binaries (excluding higher multiplicities resolved interferometrically, but unseen by imaging), and extracted measurements of the separation vectors. We combined these new measurements with those available in the WDS to determine updated orbital parameters for all our vetted calibrators. Results. We compiled a list of 13 vetted binary calibrators for observations with VLTI/GRAVITY on the UTs, and we provide orbital estimates and astrometric predictions for each of them. We show that our list guarantees that there are always two binary calibrators at least at an airmass < 2 in the sky over the Paranal observatory at any point in time. Conclusions. Any principal investigator wishing to use the dual-field mode of VLTI/GRAVITY with the UTs can now refer to this list to select an appropriate calibrator. We encourage the use of whereistheplanet to predict the astrometry of these calibrators, which seamlessly integrates with p2Gravity for VLTI/GRAVITY dual-field observing material preparation. [ABSTRACT FROM AUTHOR]

Context. The GRAVITY+ upgrade implies a complete renewal of its adaptive optics (AO) systems. Its complex design, featuring moving components between the deformable mirrors and the wavefront sensors, requires the monitoring and auto-calibrating of the lateral mis-registrations of the system while in operation. Aims. For preset and target acquisition, large lateral registration errors must be assessed in open loop to bring the system to a state where the AO loop closes. In closed loop, these errors must be monitored and corrected, without impacting the science. Methods. With respect to the first requirement, our method is perturbative, with two-dimensional modes intentionally applied to the system and correlated to a reference interaction matrix. For the second requirement, we applied a non-perturbative approach that searches for specific patterns in temporal correlations in the closed loop telemetry. This signal is produced by the noise propagation through the AO loop. Results. Our methods were validated through simulations and on the GRAVITY+ development bench. The first method robustly estimates the lateral mis-registrations, in a single fit and with a sub-subaperture resolution while in an open loop. The second method is not absolute, but it does successfully bring the system towards a negligible mis-registration error, with a limited turbulence bias. Both methods proved to robustly work on a system still under development and not fully characterised. Conclusions. Tested with Shack-Hartmann wavefront sensors, the proposed methods are versatile and easily adaptable to other AO instruments, such as the pyramid, which stands as a baseline for all future AO systems. The non-perturbative method, not relying on an interaction matrix model and being sparse in the Fourier domain, is particularly suitable to the next generation of AO systems for extremely large telescopes that will present an unprecedented level of complexity and numbers of actuators. [ABSTRACT FROM AUTHOR]

The detection of low-mass planets orbiting the nearest stars is a central stake of exoplanetary science, as they can be directly characterized much more easily than their distant counterparts. Here, we present the results of our long-term astrometric observations of the nearest binary M-dwarf Gliese 65 AB (GJ65), located at a distance of only 2.67 pc. We monitored the relative astrometry of the two components from 2016 to 2023 with the VLTI/GRAVITY interferometric instrument. We derived highly accurate orbital parameters for the stellar system, along with the dynamical masses of the two red dwarfs. The GRAVITY measurements exhibit a mean accuracy per epoch of 50−60 ms in 1.5 h of observing time using the 1.8 m Auxiliary Telescopes. The residuals of the two-body orbital fit enable us to search for the presence of companions orbiting one of the two stars (S-type orbit) through the reflex motion they imprint on the differential A–B astrometry. We detected a Neptune-mass candidate companion with an orbital period of p = 156 ± 1 d and a mass of mp = 36 ± 7 M⊕. The best-fit orbit is within the dynamical stability region of the stellar pair. It has a low eccentricity, e = 0.1 − 0.3, and the planetary orbit plane has a moderate-to-high inclination of i > 30° with respect to the stellar pair, with further observations required to confirm these values. These observations demonstrate the capability of interferometric astrometry to reach microarcsecond accuracy in the narrow-angle regime for planet detection by reflex motion from the ground. This capability offers new perspectives and potential synergies with Gaia in the pursuit of low-mass exoplanets in the solar neighborhood. [ABSTRACT FROM AUTHOR]

Aims. The goal of this work is to characterize the polarization effects of the beam path of the Very Large Telescope Interferometer (VLTI) and the GRAVITY beam combiner instrument. This is useful for two reasons: to calibrate polarimetric observations with GRAVITY for instrumental effects and to understand the systematic error introduced to the astrometry due to birefringence when observing targets with a significant intrinsic polarization. Methods. By combining a model of the VLTI light path and its mirrors and dedicated experimental data, we constructed a full polarization model of the VLTI Unit Telescopes (UTs) and the GRAVITY instrument. We first characterized all telescopes together to construct a universal UT calibration model for polarized targets with the VLTI. We then expanded the model to include the differential birefringence between the UTs. With this, we were able to constrain the systematic errors and the contrast loss for highly polarized targets. Results. Along with this paper, we have published a standalone Python package that can be used to calibrate the instrumental effects on polarimetric observations. This enables the community to use GRAVITY with the UTs to observe targets in a polarimetric observing mode. We demonstrate the calibration model with the Galactic Center star IRS 16C. For this source, we were able to constrain the polarization degree to within 0.4% and the polarization angle to within 5° while being consistent with the literature values. Furthermore, we show that there is no significant contrast loss, even if the science and fringe-tracker targets have significantly different polarization, and we determine that the phase error in such an observation is smaller than 1°, corresponding to an astrometric error of 10 µas. Conclusions. With this work, we enable the use by the community of the polarimetric mode with GRAVITY/UTs and outline the steps necessary to observe and calibrate polarized targets with GRAVITY. We demonstrate that it is possible to measure the intrinsic polarization of astrophysical sources with high precision and that polarization effects do not limit astrometric observations of polarized targets. [ABSTRACT FROM AUTHOR]

The motion of S2, one of the stars closest to the Galactic Centre, has been measured accurately and used to study the compact object at the centre of the Milky Way. It is commonly accepted that this object is a supermassive black hole, but the nature of its environment is open to discussion. Here, we investigate the possibility that dark matter in the form of an ultralight scalar field 'cloud' clusters around Sgr A*. We use the available data for S2 to perform a Markov Chain Monte Carlo analysis and find the best-fit estimates for a scalar cloud structure. Our results show no substantial evidence for such structures. When the cloud size is on the order of the size of the orbit of S2, we are able to constrain its mass to be smaller than 0.1 % of the central mass, setting a strong bound on the presence of new fields in the galactic centre. [ABSTRACT FROM AUTHOR]

We present new astrometric and polarimetric observations of flares from Sgr A* obtained with GRAVITY, the near-infrared interferometer at ESO's Very Large Telescope Interferometer (VLTI), bringing the total sample of well-covered astrometric flares to four and polarimetric flares to six. Of all flares, two are well covered in both domains. All astrometric flares show clockwise motion in the plane of the sky with a period of around an hour, and the polarization vector rotates by one full loop in the same time. Given the apparent similarities of the flares, we present a common fit, taking into account the absence of strong Doppler boosting peaks in the light curves and the EHT-measured geometry. Our results are consistent with and significantly strengthen our model from 2018. First, we find that the combination of polarization period and measured flare radius of around nine gravitational radii (9Rg ≈ 1.5RISCO, innermost stable circular orbit) is consistent with Keplerian orbital motion of hot spots in the innermost accretion zone. The mass inside the flares' radius is consistent with the 4.297 × 106M⊙ measured from stellar orbits at several thousand Rg. This finding and the diameter of the millimeter shadow of Sgr A* thus support a single black hole model. Second, the magnetic field configuration is predominantly poloidal (vertical), and the flares' orbital plane has a moderate inclination with respect to the plane of the sky, as shown by the non-detection of Doppler-boosting and the fact that we observe one polarization loop per astrometric loop. Finally, both the position angle on the sky and the required magnetic field strength suggest that the accretion flow is fueled and controlled by the winds of the massive young stars of the clockwise stellar disk 1–5″ from Sgr A*, in agreement with recent simulations. [ABSTRACT FROM AUTHOR]

Context. In the Milky Way the central massive black hole, SgrA, coexists with a compact nuclear star cluster that contains a sub-parsec concentration of fast-moving young stars called S-stars. Their location and age are not easily explained by current star formation models, and in several scenarios the presence of an intermediate-mass black hole (IMBH) has been invoked. Aims. We use GRAVITY astrometric and SINFONI, KECK, and GNIRS spectroscopic data of S2, the best known S-star, to investigate whether a second massive object could be present deep in the Galactic Centre (GC) in the form of an IMBH binary companion to SgrA. Methods. To solve the three-body problem, we used a post-Newtonian framework and consider two types of settings: (i) a hierarchical set-up where the star S2 orbits the SgrA-IMBH binary and (ii) a non-hierarchical set-up where the IMBH trajectory lies outside the S2 orbit. In both cases we explore the full 20-dimensional parameter space by employing a Bayesian dynamic nested sampling method. Results. For the hierarchical case we find the strongest constraints: IMBH masses >2000 M on orbits with smaller semi-major axes than S2 are largely excluded. For the non-hierarchical case, the chaotic nature of the problem becomes significant: the parameter space contains several pockets of valid IMBH solutions. However, a closer analysis of their impact on the resident stars reveals that IMBHs on semi-major axes larger than S2 tend to disrupt the S-star cluster in less than a million years. This makes the existence of an IMBH among the S-stars highly unlikely. Conclusions. The current S2 data do not formally require the presence of an IMBH. If an IMBH hides in the GC, it has to be either a low-mass IMBH inside the S2 orbit that moves on a short and significantly inclined trajectory or an IMBH with a semi-major axis >100. We provide the parameter maps of valid IMBH solutions in the GC and discuss the general structure of our results and how future observations can help to put even stronger constraints on the properties of IMBHs in the GC. [ABSTRACT FROM AUTHOR]

The spin of the supermassive black hole that resides at the Galactic Center can, in principle, be measured by accurate measurements of the orbits of stars that are much closer to Sgr A* than S2, the orbit of which recently provided the measurement of the gravitational redshift and the Schwarzschild precession. The GRAVITY near-infrared interferometric instrument combining the four 8m telescopes of the VLT provides a spatial resolution of 2–4 mas, breaking the confusion barrier for adaptive-optics-assisted imaging with a single 8–10m telescope. We used GRAVITY to observe Sgr A* over a period of six months in 2019 and employed interferometric reconstruction methods developed in radio astronomy to search for faint objects near Sgr A*. This revealed a slowly moving star of magnitude 18.9 in the K-band within 30 mas of Sgr A*. The position and proper motion of the star are consistent with the previously known star S62, which is at a substantially greater physical distance, but in projection passes close to Sgr A*. Observations in August and September 2019 detected S29 easily, with K-magnitude of 16.6, at approximately 130 mas from Sgr A*. The planned upgrades of GRAVITY, and further improvements in the calibration, offer greater chances of finding stars fainter than K-magnitude of 19. [ABSTRACT FROM AUTHOR]

We study the time-variable linear polarisation of Sgr A* during a bright near-infrared flare observed with the GRAVITY instrument on July 28, 2018. Motivated by the time evolution of both the observed astrometric and polarimetric signatures, we interpret the data in terms of the polarised emission of a compact region ("hotspot") orbiting a black hole in a fixed, background magnetic field geometry. We calculated a grid of general relativistic ray-tracing models, created mock observations by simulating the instrumental response, and compared predicted polarimetric quantities directly to the measurements. We take into account an improved instrument calibration that now includes the instrument's response as a function of time, and we explore a variety of idealised magnetic field configurations. We find that the linear polarisation angle rotates during the flare, which is consistent with previous results. The hotspot model can explain the observed evolution of the linear polarisation. In order to match the astrometric period of this flare, the near horizon magnetic field is required to have a significant poloidal component, which is associated with strong and dynamically important fields. The observed linear polarisation fraction of ≃30% is smaller than the one predicted by our model (≃50%). The emission is likely beam depolarised, indicating that the flaring emission region resolves the magnetic field structure close to the black hole. [ABSTRACT FROM AUTHOR]

Context. Methods used to detect giant exoplanets can be broadly divided into two categories: indirect and direct. Indirect methods are more sensitive to planets with a small orbital period, whereas direct detection is more sensitive to planets orbiting at a large distance from their host star. This dichotomy makes it difficult to combine the two techniques on a single target at once. Aims. Simultaneous measurements made by direct and indirect techniques offer the possibility of determining the mass and luminosity of planets and a method of testing formation models. Here, we aim to show how long-baseline interferometric observations guided by radial-velocity can be used in such a way. Methods. We observed the recently-discovered giant planet β Pictoris c with GRAVITY, mounted on the Very Large Telescope Interferometer. Results. This study constitutes the first direct confirmation of a planet discovered through radial velocity. We find that the planet has a temperature of T = 1250 ± 50 K and a dynamical mass of M = 8.2 ± 0.8 MJup. At 18.5 ± 2.5 Myr, this puts β Pic c close to a 'hot start' track, which is usually associated with formation via disk instability. Conversely, the planet orbits at a distance of 2.7 au, which is too close for disk instability to occur. The low apparent magnitude (MK = 14.3 ± 0.1) favours a core accretion scenario. Conclusions. We suggest that this apparent contradiction is a sign of hot core accretion, for example, due to the mass of the planetary core or the existence of a high-temperature accretion shock during formation. [ABSTRACT FROM AUTHOR]

Infrared observations of Sgr A* probe the region close to the event horizon of the black hole at the Galactic center. These observations can constrain the properties of low-luminosity accretion as well as that of the black hole itself. The GRAVITY instrument at the ESO VLTI has recently detected continuous circular relativistic motion during infrared flares which has been interpreted as orbital motion near the event horizon. Here we analyze the astrometric data from these flares, taking into account the effects of out-of-plane motion and orbital shear of material near the event horizon of the black hole. We have developed a new code to predict astrometric motion and flux variability from compact emission regions following particle orbits. Our code combines semi-analytic calculations of timelike geodesics that allow for out-of-plane or elliptical motions with ray tracing of photon trajectories to compute time-dependent images and light curves. We apply our code to the three flares observed with GRAVITY in 2018. We show that all flares are consistent with a hotspot orbiting at R ~ 9 gravitational radii with an inclination of i ~ 140°. The emitting region must be compact and less than ~5 gravitational radii in diameter. We place a further limit on the out-of-plane motion during the flare. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR) was used to investigate the interaction between N-methyl mesoporphyrin IX (NMM) and different G-quadruplex (G4) topologies. The study was associated with circular dichroism analysis (CD) to assess the topology of the G4s when they interacted with NMM. We demonstrate the high selectivity of NMM for the parallel G4 structure with a dissociation constant at least ten times lower than those of other G4 topologies. We also confirm the ability of NMM to shift the G4 conformation from both the hybrid and antiparallel topologies toward the parallel structure. [ABSTRACT FROM AUTHOR]

Context. The tip-tilt stabilisation system of the 1.8 m Auxiliary Telescopes of the Very Large Telescope Interferometer was never dimensioned for robust fringe tracking, except when atmospheric seeing conditions are excellent. Aims. Increasing the level of wavefront correction at the telescopes is expected to improve the coupling into the single-mode fibres of the instruments, and enable robust fringe tracking even in degraded conditions. Methods. We deployed a new adaptive optics module for interferometry (NAOMI) on the Auxiliary Telescopes. Results. We present its design, performance, and effect on the observations that are carried out with the interferometric instruments. [ABSTRACT FROM AUTHOR]

We present a 0.16% precise and 0.27% accurate determination of R0, the distance to the Galactic center. Our measurement uses the star S2 on its 16-year orbit around the massive black hole Sgr A* that we followed astrometrically and spectroscopically for 27 years. Since 2017, we added near-infrared interferometry with the VLTI beam combiner GRAVITY, yielding a direct measurement of the separation vector between S2 and Sgr A* with an accuracy as good as 20 μas in the best cases. S2 passed the pericenter of its highly eccentric orbit in May 2018, and we followed the passage with dense sampling throughout the year. Together with our spectroscopy, in the best cases with an error of 7 km s−1, this yields a geometric distance estimate of R0 = 8178 ± 13stat. ± 22sys. pc. This work updates our previous publication, in which we reported the first detection of the gravitational redshift in the S2 data. The redshift term is now detected with a significance level of 20σ with fredshift = 1.04 ± 0.05. [ABSTRACT FROM AUTHOR]

Aims. To date, infrared interferometry at best achieved contrast ratios of a few times 10−4 on bright targets. GRAVITY, with its dual-field mode, is now capable of high contrast observations, enabling the direct observation of exoplanets. We demonstrate the technique on HR 8799, a young planetary system composed of four known giant exoplanets. Methods. We used the GRAVITY fringe tracker to lock the fringes on the central star, and integrated off-axis on the HR 8799 e planet situated at 390 mas from the star. Data reduction included post-processing to remove the flux leaking from the central star and to extract the coherent flux of the planet. The inferred K band spectrum of the planet has a spectral resolution of 500. We also derive the astrometric position of the planet relative to the star with a precision on the order of 100 μas. Results. The GRAVITY astrometric measurement disfavors perfectly coplanar stable orbital solutions. A small adjustment of a few degrees to the orbital inclination of HR 8799 e can resolve the tension, implying that the orbits are close to, but not strictly coplanar. The spectrum, with a signal-to-noise ratio of ≈5 per spectral channel, is compatible with a late-type L brown dwarf. Using Exo-REM synthetic spectra, we derive a temperature of 1150 ± 50 K and a surface gravity of 104.3 ± 0.3 cm s2. This corresponds to a radius of 1.17−0.11+0.13RJup 1. 17 − 0.11 + 0.13 R Jup $ 1.17^{+0.13}_{-0.11}\,R_{\mathrm{Jup}} $ and a mass of 10−4+7MJup 10 − 4 + 7 M Jup $ 10^{+7}_{-4}\,M_{\mathrm{Jup}} $ , which is an independent confirmation of mass estimates from evolutionary models. Our results demonstrate the power of interferometry for the direct detection and spectroscopic study of exoplanets at close angular separations from their stars. [ABSTRACT FROM AUTHOR]

We present the first optical observation of the microquasar SS 433 at sub-milliarcsecond (mas) scale obtained with the GRAVITY instrument on the Very Large Telescope interferometer (VLTI). The 3.5-h exposure reveals a rich K-band spectrum dominated by hydrogen Br and He i lines, as well as (red-shifted) emission lines coming from the jets. The K-band-continuum-emitting region is dominated by a marginally resolved point source (<1 mas) embedded inside a diffuse background accounting for 10% of the total flux. The jet line positions agree well with the ones expected from the jet kinematic model, an interpretation also supported by the consistent sign (i.e., negative/positive for the receding/approaching jet component) of the phase shifts observed in the lines. The significant visibility drop across the jet lines, together with the small and nearly identical phases for all baselines, point toward a jet that is offset by less than 0.5 mas from the continuum source and resolved in the direction of propagation, with a typical size of 2 mas. The jet position angle of ~80° is consistent with the expected one at the observation date. Jet emission so close to the central binary system would suggest that line locking, if relevant to explain the amplitude and stability of the 0:26c jet velocity, operates on elements heavier than hydrogen. The Br profile is broad and double peaked. It is better resolved than the continuum and the change of the phase signal sign across the line on all baselines suggests an East-West-oriented geometry similar to the jet direction and supporting a (polar) disk wind origin. [ABSTRACT FROM AUTHOR]

GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130m diameter angular resolution and a collecting area of 200m². The instrument comprises fiber fed integrated optics beam combination, high resolution spectroscopy, built-in beam analysis and control, near-infrared wavefront sensing, phasetracking, dual-beam operation, and laser metrology. GRAVITY opens up to optical/infrared interferometry the techniques of phase referenced imaging and narrow angle astrometry, in many aspects following the concepts of radio interferometry. This article gives an overview of GRAVITY and reports on the performance and the first astronomical observations during commissioning in 2015/16. We demonstrate phase-tracking on stars as faint as mK ≈ 10 mag, phase-referenced interferometry of objects fainter than mK ≈ 15 mag with a limiting magnitude of mK ≈ 17 mag, minute long coherent integrations, a visibility accuracy of better than 0:25%, and spectro-differential phase and closure phase accuracy better than 0:5°, corresponding to a differential astrometric precision of better than ten microarcseconds (µas). The dual-beam astrometry, measuring the phase difference of two objects with laser metrology, is still under commissioning. First observations show residuals as low as 50 µas when following objects over several months. We illustrate the instrument performance with the observations of archetypical objects for the different instrument modes. Examples include the Galactic center supermassive black hole and its fast orbiting star S2 for phase referenced dual-beam observations and infrared wavefront sensing, the high mass X-ray binary BP Cru and the active galactic nucleus of PDS 456 for a few µas spectro-differential astrometry, the T Tauri star S CrA for a spectro-differential visibility analysis, ζ Tel and 24 Cap for high accuracy visibility observations, and η Car for interferometric imaging with GRAVITY. [ABSTRACT FROM AUTHOR]

Aim To compare the in vitro biocompatibility of Biodentine™ and White ProRoot® mineral trioxide aggregate ( MTA®) with MG63 osteoblast-like cells and to characterize the cement surface. Methodology A direct contact model for MG63 osteoblast-like cells with cements was used for 1, 3 and 5 days. Four end-points were investigated: (i) cement surface characterization by atomic force microscopy ( AFM), (ii) cell viability by MTT assay, (iii) protein amount quantification by Bradford assay and (iv) cell morphology by SEM. Statistical analyses were performed by analysis of variance ( anova) with a repetition test method. Results The roughness of the cements was comparable as revealed by AFM analysis. The MTT test for Biodentine™ was similar to that of MTA®. Biodentine™ and MTA® induced a similar but slight decrease in metabolic activity. The amount of total protein was significantly enhanced at day three ( P < 0.05) but slightly decreased at day five for both tested samples. Biodentine™ was tolerated as well as MTA® in all cytotoxicity assays. SEM observations showed improvement of cell attachment and proliferation on both material surfaces following the three incubation periods. Conclusion The biocompatibility of Biodentine™ to bone cells was comparable to MTA®. [ABSTRACT FROM AUTHOR]

Context. A basic principle of long baseline interferometry is that an optical path difference (OPD) directly translates into an astrometric measurement. In the simplest case, the OPD is equal to the scalar product between the vector that links the two telescopes and the normalized vector pointing toward the star. However, in some circumstances, too simple an interpretation of this scalar product leads to seemingly conflicting results, called here "the baseline paradox". Aims. For micro-arcsecond accuracy astrometry, we have to model the metrology measurement in full. It involves a complex system subject to many optical effects: from pure baseline errors to static, quasi-static, and high-order optical aberrations. The goal of this paper is to present the strategy used by the "General Relativity Analysis via VLT InTerferometrY" instrument (GRAVITY) to minimize the biases introduced by these defects. Methods. It is possible to give an analytical formula for how the baselines and tip-tilt errors affect the astrometric measurement. This formula depends on the limit points of three type of baselines: the wide-angle baseline, the narrow-angle baseline, and the imaging baseline. We also numerically include non-common path, higher order aberrations, whose amplitudes were measured during technical time at the Very Large Telescope Interferometer (VLTI). We end by simulating the influence of high-order, common-path aberrations due to atmospheric residuals calculated from a Monte-Carlo simulation tool for adaptive optics (AO) systems. Results. The result of this work is an error budget of the biases caused by the multiple optical imperfections, including optical dispersion. We show that the beam stabilization through both focal and pupil tracking is crucial to the GRAVITY system. Assuming the instrument pupil is stabilized at a 4 cm level on M1 and a field tracking below 0.2 λ/D, we show that GRAVITY will be able to reach its objective of 10 μas accuracy. [ABSTRACT FROM AUTHOR]

We aimed to investigate whether micro-net on stent could preserve the index of msicrocirculatory resistance (IMR) after primary percutaneous coronary intervention (PCI) in patients with acutemyocardial infarction (AMI). Fifty deux patients with AMI were randomized into two groups: primary PCI with micro-net on stent (MGUARD group, n = 25) and primary PCI with any commercially available (DES group, n = 27). As the primary endpoint, IMR was measured immediately after primary PCI using a pressure-temperature sensor-tipped coronary wire. The secondary endpoint was the left ventricular ejection fraction (LVEF) at six-month follow-up. The IMR in MGUARD group was significantly lower than in DES group (39.6 ± 26.2 U vs. 75.4 ± 60.5 U, P = 0.01). No significant differences in baseline EF (56.2 ± 10.3% vs. 54.9 ± 7.73%, P = 0.7), however, there were significant differences in follow-up EF (63.2 ± 3.8% vs. 54.7 ± 7.79%, P = 0.001). A micro-net on stent significantly improved CMVD compared with a traditional DES in primary PCI and appear as a useful technological option to manage the thrombus. [ABSTRACT FROM AUTHOR]

Résumé Introduction La thérapie intravésicale par le bacille de Calmette et Guérin (BCG) a démontré son efficacité en traitement de première intention pour les cancers urothéliaux non infiltrants. Les principaux effets secondaires sont locaux et rapidement résolutifs. Néanmoins, une dissémination microbienne est possible pouvant se compliquer d’atteintes viscérales potentiellement létales telles que des hépatites, pneumopathies, aortites, et localisation au tissu hématopoïétique. Observation Nous rapportons l’observation d’un patient de 83 ans ayant présenté une hépatite granulomateuse révélant une infection mycobactérienne disséminée consécutive à l’utilisation du BCG en immunothérapie intravésicale 2 ans auparavant. Des atteintes de l’aorte, de la rate et de la moelle osseuse étaient associées. Le délai diagnostique était de 5 mois et l’évolution lentement favorable sous antibiothérapie adaptée. Conclusion La présence de lésions granulomateuses chez un homme traité par BCG-thérapie intravésicale doit faire craindre une infection généralisée, même plusieurs années à distance du traitement. Introduction Intravesical therapy with bacillus Calmette-Guérin (BCG) has proved to be effective in the treatment of superficial bladder tumors. Side-effects include local infections and rarely disseminated BCG infection with multiple end organ complications such as granulomatous hepatitis, pneumonitis, aortitis and bone marrow involvement. Case report We report an 83-year-old man who presented with chronic granulomatous hepatitis. This was related to intravesical BCG therapy received two years earlier for superficial bladder cancer. Aortitis, splenic infarction and hematopoietic involvement were also diagnosed. Outcome was favorable following adapted antibiotic course. Conclusion This case report highlights the possibility of widespread BCG infection following intravesical treatment, and the need for vigilance in patients with a history of such a therapy even several years later. [ABSTRACT FROM AUTHOR]

Aim To compare the in vitro biocompatibility of Biodentine™ and White ProRoot® mineral trioxide aggregate ( MTA®) with MG63 osteoblast-like cells and to characterize the cement surface. Methodology A direct contact model for MG63 osteoblast-like cells with cements was used for 1, 3 and 5 days. Four end-points were investigated: (i) cement surface characterization by atomic force microscopy ( AFM), (ii) cell viability by MTT assay, (iii) protein amount quantification by Bradford assay and (iv) cell morphology by SEM. Statistical analyses were performed by analysis of variance ( anova) with a repetition test method. Results The roughness of the cements was comparable as revealed by AFM analysis. The MTT test for Biodentine™ was similar to that of MTA®. Biodentine™ and MTA® induced a similar but slight decrease in metabolic activity. The amount of total protein was significantly enhanced at day three ( P < 0.05) but slightly decreased at day five for both tested samples. Biodentine™ was tolerated as well as MTA® in all cytotoxicity assays. SEM observations showed improvement of cell attachment and proliferation on both material surfaces following the three incubation periods. Conclusion The biocompatibility of Biodentine™ to bone cells was comparable to MTA®. [ABSTRACT FROM AUTHOR]

Abstract: Reassessment of antibiotic therapy (RA) after 3 days is constitutive of French antibiotic stewardship. This delay is required because of the need for clinical reappraisal and for obtaining microbiological data. Our aim was to determine the factors associated with an effective RA. Patients and method: A prospective study was made in a 350-bed general hospital in which all prescriptions are computerized and validated daily by prescribers. All curative antibiotic therapies were reassessed during 4 weeks. RA was defined as effective if the initial antibiotic treatment was modified. All clinical, biological, and radiological data having contributed to the initial prescription and to RA were recorded during bedside visit with the prescribers, two hospital physicians and one infectious diseases specialist. Results: In one month, 148 antibiotic treatments were reassessed. Pulmonary, digestive, and urinary infections accounted for two thirds of the cases. An effective RA was recorded in 28 cases (19%) and associated with hospitalization in the ICU (P =0.001), imaging supporting the diagnosis (P =0.016), and persistence or aggravation of clinical signs (P =0.007). Microbiological findings were not contributive to an effective RA. Conclusion: RA was associated to hospitalization in the ICU, to an inflammatory syndrome, and to the clinical outcome after 3 days. These results should help to improve the implementation of infectious diseases advice. [Copyright &y& Elsevier]