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Acceleration and transport of relativistic electrons in the jets of the microquasar SS 433. Science 2024; 383:402-406. [PMID: 38271522 DOI: 10.1126/science.adi2048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 12/04/2023] [Indexed: 01/27/2024]
Abstract
SS 433 is a microquasar, a stellar binary system that launches collimated relativistic jets. We observed SS 433 in gamma rays using the High Energy Stereoscopic System (H.E.S.S.) and found an energy-dependent shift in the apparent position of the gamma-ray emission from the parsec-scale jets. These observations trace the energetic electron population and indicate that inverse Compton scattering is the emission mechanism of the gamma rays. Our modeling of the energy-dependent gamma-ray morphology constrains the location of particle acceleration and requires an abrupt deceleration of the jet flow. We infer the presence of shocks on either side of the binary system, at distances of 25 to 30 parsecs, and that self-collimation of the precessing jets forms the shocks, which then efficiently accelerate electrons.
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Multi-material spectral photon-counting micro-CT with minimum residual decomposition and self-supervised deep denoising. OPTICS EXPRESS 2022; 30:42995-43011. [PMID: 36523008 DOI: 10.1364/oe.471439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 09/05/2022] [Indexed: 06/17/2023]
Abstract
Spectral micro-CT imaging with direct-detection energy discriminating photon counting detectors having small pixel size (< 100×100 µm2) is mainly hampered by: i) the limited energy resolution of the imaging device due to charge sharing effects and ii) the unavoidable noise amplification in the images resulting from basis material decomposition. In this work, we present a cone-beam micro-CT setup that includes a CdTe photon counting detector implementing a charge summing hardware solution to correct for the charge-sharing issue and an innovative image processing pipeline based on accurate modeling of the spectral response of the imaging system, an improved basis material decomposition (BMD) algorithm named minimum-residual BMD (MR-BMD), and self-supervised deep convolutional denoising. Experimental tomographic projections having a pixel size of 45×45 µm2 of a plastinated mouse sample including I, Ba, and Gd small cuvettes were acquired. Results demonstrate the capability of the combined hardware and software tools to sharply discriminate even between materials having their K-Edge separated by a few keV, such as e.g., I and Ba. By evaluating the quality of the reconstructed decomposed images (water, bone, I, Ba, and Gd), the quantitative performances of the spectral system are here assessed and discussed.
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Search for Dark Matter Annihilation Signals in the H.E.S.S. Inner Galaxy Survey. PHYSICAL REVIEW LETTERS 2022; 129:111101. [PMID: 36154418 DOI: 10.1103/physrevlett.129.111101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 01/17/2022] [Accepted: 07/13/2022] [Indexed: 06/16/2023]
Abstract
The central region of the Milky Way is one of the foremost locations to look for dark matter (DM) signatures. We report the first results on a search for DM particle annihilation signals using new observations from an unprecedented γ-ray survey of the Galactic Center (GC) region, i.e., the Inner Galaxy Survey, at very high energies (≳100 GeV) performed with the H.E.S.S. array of five ground-based Cherenkov telescopes. No significant γ-ray excess is found in the search region of the 2014-2020 dataset and a profile likelihood ratio analysis is carried out to set exclusion limits on the annihilation cross section ⟨σv⟩. Assuming Einasto and Navarro-Frenk-White (NFW) DM density profiles at the GC, these constraints are the strongest obtained so far in the TeV DM mass range. For the Einasto profile, the constraints reach ⟨σv⟩ values of 3.7×10^{-26} cm^{3} s^{-1} for 1.5 TeV DM mass in the W^{+}W^{-} annihilation channel, and 1.2×10^{-26} cm^{3} s^{-1} for 0.7 TeV DM mass in the τ^{+}τ^{-} annihilation channel. With the H.E.S.S. Inner Galaxy Survey, ground-based γ-ray observations thus probe ⟨σv⟩ values expected from thermal-relic annihilating TeV DM particles.
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Abstract
Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material slams into the companion star's wind can accelerate particles. We report very-high-energy (VHE, [Formula: see text]) gamma rays from the recurrent nova RS Ophiuchi, up to a month after its 2021 outburst, observed using the High Energy Stereoscopic System. The VHE emission has a similar temporal profile to lower-energy GeV emission, indicating a common origin, with a two-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic-rays to very high energies.
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Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow. Science 2021; 372:1081-1085. [PMID: 34083487 DOI: 10.1126/science.abe8560] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 04/07/2021] [Indexed: 11/02/2022]
Abstract
Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.
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P6589Genetic risks for arrhythmia phenotypes in dilated cardiomyopathy. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.1177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Background
Genotype-phenotype correlations in dilated cardiomyopathy (DCM) and in particular the effects of gene variants on clinical outcomes remain poorly understood.
Purpose
To investigate the prognostic role of genetic variant carrier status in a large cohort of DCM patients.
Methods
We analyzed 487 DCM patients by next-generation sequencing and categorized the disease genes into functional gene groups. The following composite outcome measures were assessed: 1) all-cause mortality, heart transplantation or left ventricular assist device (D/HTx/VAD); 2) sudden cardiac death or malignant ventricular arrhythmias (SCD/MVAs); 3) heart failure related death, heart transplantation or left ventricular assist device implantation (DHF/HTx/VAD).
Results
A total of 187 pathogenic/likely pathogenic variants were found in 180 patients (37%): 55 (11%) TTN; 19 (4%) LMNA; 24 (5%) structural cytoskeleton-Z disk genes; 16 (3%) desmosomal genes; 47 (10%) sarcomeric genes; 8 (2%) ion channels genes; 11 (2%) other genes. The occurrence of D/HTx/VAD was no different between variant carriers and non-carriers (p=0.17). However, carriers of desmosomal and LMNA variants experienced the highest rate of SCD/MVA, which was independent of the left ventricular ejection fraction.
Conclusions
Desmosomal and LMNA gene variants identify the subset of DCM patients at greatest risk for SCD and life-threatening ventricular arrhythmias, regardless the left ventricular ejection fraction.
Acknowledgement/Funding
National Institutes of Health grants R01 HL69071, HL116906, and AHA17GRNT33670495
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Towards In Vivo K-Edge X-Ray Micro-CT with the Pixirad-I/Pixie-III Detector. IFMBE PROCEEDINGS 2019. [DOI: 10.1007/978-981-10-9035-6_22] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A. Science 2018; 361:science.aat1378. [DOI: 10.1126/science.aat1378] [Citation(s) in RCA: 451] [Impact Index Per Article: 75.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 06/08/2018] [Indexed: 11/02/2022]
Abstract
Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017, we detected a high-energy neutrino, IceCube-170922A, with an energy of ~290 tera–electron volts. Its arrival direction was consistent with the location of a known γ-ray blazar, TXS 0506+056, observed to be in a flaring state. An extensive multiwavelength campaign followed, ranging from radio frequencies to γ-rays. These observations characterize the variability and energetics of the blazar and include the detection of TXS 0506+056 in very-high-energy γ-rays. This observation of a neutrino in spatial coincidence with a γ-ray–emitting blazar during an active phase suggests that blazars may be a source of high-energy neutrinos.
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Search for γ-Ray Line Signals from Dark Matter Annihilations in the Inner Galactic Halo from 10 Years of Observations with H.E.S.S. PHYSICAL REVIEW LETTERS 2018; 120:201101. [PMID: 29864326 DOI: 10.1103/physrevlett.120.201101] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 03/05/2018] [Indexed: 06/08/2023]
Abstract
Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy γ rays. The central region of the Milky Way halo is one of the most promising targets given its large amount of DM and proximity to Earth. We report on a search for a monoenergetic spectral line from self-annihilations of DM particles in the energy range from 300 GeV to 70 TeV using a two-dimensional maximum likelihood method taking advantage of both the spectral and spatial features of the signal versus background. The analysis makes use of Galactic center observations accumulated over ten years (2004-2014) with the H.E.S.S. array of ground-based Cherenkov telescopes. No significant γ-ray excess above the background is found. We derive upper limits on the annihilation cross section ⟨σv⟩ for monoenergetic DM lines at the level of 4×10^{-28} cm^{3} s^{-1} at 1 TeV, assuming an Einasto DM profile for the Milky Way halo. For a DM mass of 1 TeV, they improve over the previous ones by a factor of 6. The present constraints are the strongest obtained so far for DM particles in the mass range 300 GeV-70 TeV. Ground-based γ-ray observations have reached sufficient sensitivity to explore relevant velocity-averaged cross sections for DM annihilation into two γ-ray photons at the level expected from the thermal relic density for TeV DM particles.
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The role of extracorporeal membrane oxygenation in severe pulmonary coccidioidomycosis. Heart Lung 2018; 47:261-263. [PMID: 29622277 DOI: 10.1016/j.hrtlng.2018.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/16/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Severe coccidioidal pneumonia with acute respiratory distress syndrome (ARDS) is associated with high mortality. Extracorporeal membrane oxygenation (ECMO) has been applied successfully to other severe fungal pneumonia associated with ARDS. We review our experience with the use of ECMO in severe coccidioidal ARDS. OBJECTIVES To review indications and outcome of ECMO in severe pulmonary coccidioidomycosis. METHODS Three cases of severe ARDS caused by coccidioidomycosis are presented. All were managed with ECMO. Clinical course, complications, antifungal therapy and outcome are reviewed. RESULTS Three cases of severe coccidioidal ARDS survived after treatment with ECMO. Common complications included bacterial pneumonia, encephalopathy and critical illness myopathy. They received liposomal amphotericin during ECMO, and transitioned to azole therapy. All required prolonged hospitalization and rehabilitation. CONCLUSIONS ECMO was life-saving in cases of coccidioidal ARDS. Common complications included pneumonia, encephalopathy and critical illness myopathy. All cases were successfully managed with liposomal amphotericin followed by azole therapy. They required prolonged hospitalization and rehabilitation.
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11
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A Framework for Iterative Reconstruction in Phase-Contrast Computed Tomography Dedicated to the Breast. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2017. [DOI: 10.1109/trpms.2017.2749059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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12
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Size and specimen-dependent strategy for x-ray micro-ct and tem correlative analysis of nervous system samples. Sci Rep 2017; 7:2858. [PMID: 28588216 PMCID: PMC5460131 DOI: 10.1038/s41598-017-02998-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 03/30/2017] [Indexed: 11/08/2022] Open
Abstract
Correlative approaches are a powerful tool in the investigation of biological samples, but require specific preparation procedures to maintain the strength of the employed methods. Here we report the optimization of the embedding protocol of nervous system samples for a correlative synchrotron X-ray computed microtomography (micro-CT) and transmission electron microscopy (TEM) approach. We demonstrate that it is possible to locate, with the micrometric resolution of micro-CT, specific volumes of interest for a further ultrastructural characterization to be performed with TEM. This approach can be applied to samples of different size and morphology up to several cm. Our optimized method represents an invaluable tool for investigating those pathologies in which microscopic alterations are localized in few confined regions, rather than diffused in entire tissues, organs or systems. We present a proof of concept of our method in a mouse model of Globoid Cells Leukodistrophy.
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Optimization of propagation-based x-ray phase-contrast tomography for breast cancer imaging. Phys Med Biol 2017; 62:2315-2332. [DOI: 10.1088/1361-6560/aa5d3d] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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H.E.S.S. Limits on Linelike Dark Matter Signatures in the 100 GeV to 2 TeV Energy Range Close to the Galactic Center. PHYSICAL REVIEW LETTERS 2016; 117:151302. [PMID: 27768338 DOI: 10.1103/physrevlett.117.151302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Indexed: 06/06/2023]
Abstract
UNLABELLED A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l=-1.5°, b=0° and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S. RESULTS No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.
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Search for Dark Matter Annihilations towards the Inner Galactic Halo from 10 Years of Observations with H.E.S.S. PHYSICAL REVIEW LETTERS 2016; 117:111301. [PMID: 27661677 DOI: 10.1103/physrevlett.117.111301] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Indexed: 06/06/2023]
Abstract
The inner region of the Milky Way halo harbors a large amount of dark matter (DM). Given its proximity, it is one of the most promising targets to look for DM. We report on a search for the annihilations of DM particles using γ-ray observations towards the inner 300 pc of the Milky Way, with the H.E.S.S. array of ground-based Cherenkov telescopes. The analysis is based on a 2D maximum likelihood method using Galactic Center (GC) data accumulated by H.E.S.S. over the last 10 years (2004-2014), and does not show any significant γ-ray signal above background. Assuming Einasto and Navarro-Frenk-White DM density profiles at the GC, we derive upper limits on the annihilation cross section ⟨σv⟩. These constraints are the strongest obtained so far in the TeV DM mass range and improve upon previous limits by a factor 5. For the Einasto profile, the constraints reach ⟨σv⟩ values of 6×10^{-26} cm^{3} s^{-1} in the W^{+}W^{-} channel for a DM particle mass of 1.5 TeV, and 2×10^{-26} cm^{3} s^{-1} in the τ^{+}τ^{-} channel for a 1 TeV mass. For the first time, ground-based γ-ray observations have reached sufficient sensitivity to probe ⟨σv⟩ values expected from the thermal relic density for TeV DM particles.
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16
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Phase-sensitive breast CT with monochromatic beam towards the clinical trial. Phys Med 2016. [DOI: 10.1016/j.ejmp.2016.07.553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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17
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Comparison among iterative reconstruction techniques for phase-sensitive breast tomography. Phys Med 2016. [DOI: 10.1016/j.ejmp.2016.07.729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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18
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Abstract
The aim of the SYRMA-CT collaboration is to set-up the first clinical trial of phase-contrast breast CT with synchrotron radiation (SR). In order to combine high image quality and low delivered dose a number of innovative elements are merged: a CdTe single photon counting detector, state-of-the-art CT reconstruction and phase retrieval algorithms. To facilitate an accurate exam optimization, a Monte Carlo model was developed for dose calculation using GEANT4. In this study, high isotropic spatial resolution (120 μm)(3) CT scans of objects with dimensions and attenuation similar to a human breast were acquired, delivering mean glandular doses in the range of those delivered in clinical breast CT (5-25 mGy). Due to the spatial coherence of the SR beam and the long distance between sample and detector, the images contain, not only absorption, but also phase information from the samples. The application of a phase-retrieval procedure increases the contrast-to-noise ratio of the tomographic images, while the contrast remains almost constant. After applying the simultaneous algebraic reconstruction technique to low-dose phase-retrieved data sets (about 5 mGy) with a reduced number of projections, the spatial resolution was found to be equal to filtered back projection utilizing a four fold higher dose, while the contrast-to-noise ratio was reduced by 30%. These first results indicate the feasibility of clinical breast CT with SR.
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Imaging collagen packing dynamics during mineralization of engineered bone tissue. Acta Biomater 2015; 23:309-316. [PMID: 26049151 DOI: 10.1016/j.actbio.2015.05.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/08/2015] [Accepted: 05/28/2015] [Indexed: 01/03/2023]
Abstract
The structure and organization of the Type I collagen microfibrils during mineral nanoparticle formation appear as the key factor for a deeper understanding of the biomineralization mechanism and for governing the bone tissue physical properties. In this work we investigated the dynamics of collagen packing during ex-vivo mineralization of ceramic porous hydroxyapatite implant scaffolds using synchrotron high resolution X-ray phase contrast micro-tomography (XPCμT) and synchrotron scanning micro X-ray diffraction (SμXRD). While XPCμT provides the direct 3D image of the collagen fibers network organization with micrometer spatial resolution, SμXRD allows to probe the structural statistical fluctuations of the collagen fibrils at nanoscale. In particular we imaged the lateral spacing and orientation of collagen fibrils during the anisotropic growth of mineral nanocrystals. Beyond throwing light on the bone regeneration multiscale process, this approach can provide important information in the characterization of tissue in health, aging and degeneration conditions. STATEMENT OF SIGNIFICANCE BONE grafts are the most common transplants after the blood transfusions. This makes the bone-tissue regeneration research of pressing scientific and social impact. Bone is a complex hierarchical structure, where the interplay of organic and inorganic mineral phases at different length scale (from micron to atomic scale) affect its functionality and health. Thus, the understanding of bone tissue regeneration requires to image its spatial-temporal evolution (i) with high spatial resolution and (ii) at different length scale. We exploited high spatial resolution X-ray Phase Contrast micro Tomography and Scanning micro X-ray Diffraction in order to get new insight on the engineered tissue formation mechanisms. This approach could open novel routes for the early detection of different degenerative conditions of tissue.
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Clinical application of low-dose phase contrast breast CT: methods for the optimization of the reconstruction workflow. BIOMEDICAL OPTICS EXPRESS 2015; 6:3099-3112. [PMID: 26309770 PMCID: PMC4541534 DOI: 10.1364/boe.6.003099] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/03/2015] [Accepted: 07/06/2015] [Indexed: 05/29/2023]
Abstract
Results are presented of a feasibility study of three-dimensional X-ray tomographic mammography utilising in-line phase contrast. Experiments were performed at SYRMEP beamline of Elettra synchrotron. A specially designed plastic phantom and a mastectomy sample containing a malignant lesion were used to study the reconstructed image quality as a function of different image processing operations. Detailed evaluation and optimization of image reconstruction workflows have been carried out using combinations of several advanced computed tomography algorithms with different pre-processing and post-processing steps. Special attention was paid to the effect of phase retrieval on the diagnostic value of the reconstructed images. A number of objective image quality indices have been applied for quantitative evaluation of the results, and these were compared with subjective assessments of the same images by three experienced radiologists and one pathologist. The outcomes of this study provide practical guidelines for the optimization of image processing workflows in synchrotron-based phase-contrast mammo-tomography.
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Multiple mechanisms of nitrate sensing by Arabidopsis nitrate transceptor NRT1.1. NATURE PLANTS 2015; 1:15015. [PMID: 27246882 DOI: 10.1038/nplants.2015.15] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 01/27/2015] [Indexed: 05/20/2023]
Abstract
In Arabidopsis the plasma membrane nitrate transceptor (transporter/receptor) NRT1.1 governs many physiological and developmental responses to nitrate. Alongside facilitating nitrate uptake, NRT1.1 regulates the expression levels of many nitrate assimilation pathway genes, modulates root system architecture, relieves seed dormancy and protects plants from ammonium toxicity. Here, we assess the functional and phenotypic consequences of point mutations in two key residues of NRT1.1 (P492 and T101). We show that the point mutations differentially affect several of the NRT1.1-dependent responses to nitrate, namely the repression of lateral root development at low nitrate concentrations, and the short-term upregulation of the nitrate-uptake gene NRT2.1, and its longer-term downregulation, at high nitrate concentrations. We also show that these mutations have differential effects on genome-wide gene expression. Our findings indicate that NRT1.1 activates four separate signalling mechanisms, which have independent structural bases in the protein. In particular, we present evidence to suggest that the phosphorylated and non-phosphorylated forms of NRT1.1 at T101 have distinct signalling functions, and that the nitrate-dependent regulation of root development depends on the phosphorylated form. Our findings add to the evidence that NRT1.1 is able to trigger independent signalling pathways in Arabidopsis in response to different environmental conditions.
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Constraints on an annihilation signal from a core of constant dark matter density around the milky way center with H.E.S.S. PHYSICAL REVIEW LETTERS 2015; 114:081301. [PMID: 25768750 DOI: 10.1103/physrevlett.114.081301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Indexed: 06/04/2023]
Abstract
An annihilation signal of dark matter is searched for from the central region of the Milky Way. Data acquired in dedicated on-off observations of the Galactic center region with H.E.S.S. are analyzed for this purpose. No significant signal is found in a total of ∼9 h of on-off observations. Upper limits on the velocity averaged cross section, ⟨σv⟩, for the annihilation of dark matter particles with masses in the range of ∼300 GeV to ∼10 TeV are derived. In contrast to previous constraints derived from observations of the Galactic center region, the constraints that are derived here apply also under the assumption of a central core of constant dark matter density around the center of the Galaxy. Values of ⟨σv⟩ that are larger than 3×10^{-24} cm^{3}/s are excluded for dark matter particles with masses between ∼1 and ∼4 TeV at 95% C.L. if the radius of the central dark matter density core does not exceed 500 pc. This is the strongest constraint that is derived on ⟨σv⟩ for annihilating TeV mass dark matter without the assumption of a centrally cusped dark matter density distribution in the search region.
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Pursuit Of Diagnosis and Wine in California-When A DVT Is More Than a Blood Clot! Chest 2013. [DOI: 10.1378/chest.1705592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Search for photon-linelike signatures from dark matter annihilations with H.E.S.S. PHYSICAL REVIEW LETTERS 2013; 110:041301. [PMID: 25166149 DOI: 10.1103/physrevlett.110.041301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Indexed: 06/03/2023]
Abstract
Gamma-ray line signatures can be expected in the very-high-energy (E(γ)>100 GeV) domain due to self-annihilation or decay of dark matter (DM) particles in space. Such a signal would be readily distinguishable from astrophysical γ-ray sources that in most cases produce continuous spectra that span over several orders of magnitude in energy. Using data collected with the H.E.S.S. γ-ray instrument, upper limits on linelike emission are obtained in the energy range between ∼ 500 GeV and ∼ 25 TeV for the central part of the Milky Way halo and for extragalactic observations, complementing recent limits obtained with the Fermi-LAT instrument at lower energies. No statistically significant signal could be found. For monochromatic γ-ray line emission, flux limits of (2 × 10(-7) -2 × 10(-5)) m(-2) s(-1) sr(-1) and (1 × 10(-8) -2 × 10(-6)) m(-2) s(-1)sr(-1) are obtained for the central part of the Milky Way halo and extragalactic observations, respectively. For a DM particle mass of 1 TeV, limits on the velocity-averaged DM annihilation cross section ⟨σv⟩(χχ → γγ) reach ∼ 10(-27) cm(3)s(-1), based on the Einasto parametrization of the Galactic DM halo density profile.
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Poster Session 2. Europace 2011. [DOI: 10.1093/europace/eur222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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26
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Search for a dark matter annihilation signal from the galactic center halo with H.E.S.S. PHYSICAL REVIEW LETTERS 2011; 106:161301. [PMID: 21599352 DOI: 10.1103/physrevlett.106.161301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 01/12/2011] [Indexed: 05/30/2023]
Abstract
A search for a very-high-energy (VHE; ≥100 GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards a region of projected distance r∼45-150 pc from the Galactic center. The background-subtracted γ-ray spectrum measured with the High Energy Stereoscopic System (H.E.S.S.) γ-ray instrument in the energy range between 300 GeV and 30 TeV shows no hint of a residual γ-ray flux. Assuming conventional Navarro-Frenk-White and Einasto density profiles, limits are derived on the velocity-weighted annihilation cross section (σv) as a function of the DM particle mass. These are among the best reported so far for this energy range and in particular differ only little between the chosen density profile parametrizations. In particular, for the DM particle mass of ∼1 TeV, values for (σv) above 3×10(-25) cm(3) s(-1) are excluded for the Einasto density profile.
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Chronic antigenic stimuli as a possible explanation for the immunodepression caused by liver cirrhosis. Clin Exp Immunol 2009; 158:219-29. [PMID: 19737142 DOI: 10.1111/j.1365-2249.2009.04005.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The objectives of this work were the analysis of the functional characteristics of circulating monocytes and T lymphocytes in patients with liver cirrhosis, and evaluation of the relationship with an increased exposure to antigens due to bacterial translocation. Forty patients with liver cirrhosis (20 with compensated cirrhosis and 20 with ascitic decompensation) and 20 healthy control subjects were studied. Bacterial translocation was evaluated by serum levels of lipopolysaccharide binding protein (LBP). Macrophage activation was studied by CD40 antigen expression. T lymphocytes were analysed for activation (CD25(+), CD122(+)), effector function (CD8(+)CD45RO(+)CD57(+)), apoptosis (CD95(+)) and regulatory abilities, either by analysis of the membrane expression of co-stimulatory molecules CD80, CD86 and CD28, or by quantification of regulatory T cells CD4(+)CD25(high)forkhead box P3 (FoxP3). The percentage of activated monocytes and T lymphocytes in patients was increased significantly. The proportions of effector senescent cells and of those near to apoptosis were also significantly higher. With respect to these proportions, there were no significant differences between patients in function of the presence or absence of decompensation or in function of the increased or normal values of LBP. Conversely, those patients with elevated levels of LBP presented a significantly higher frequency of regulatory T cells than those with normal levels. In conclusion, patients with liver cirrhosis showed an intensive activation state with a higher percentage of cells committed to activation-induced death, even in non-advanced stages. It is possible that bacterial permeability and endotoxaemia contribute to the expansion of those lymphocyte populations implicated in the prevention of a more severe antigen-induced immunopathology.
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Radio Imaging of the Very-High-Energy γ-Ray Emission Region in the Central Engine of a Radio Galaxy. Science 2009; 325:444-8. [PMID: 19574351 DOI: 10.1126/science.1175406] [Citation(s) in RCA: 157] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Prélèvements à coeur arrêté : problèmes organisationnels. Ing Rech Biomed 2008. [DOI: 10.1016/s1959-0318(08)74445-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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[EVAL MATER: Proposal for a paediatric evaluation of linguistic and psychomotor competences during the 1st medical check-up in nursery school]. Arch Pediatr 2008; 15:397-405. [PMID: 18378127 DOI: 10.1016/j.arcped.2008.01.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Accepted: 01/30/2008] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To prevent learning disorders, the authors propose a standardized approach of linguistic competences and psychomotor development in young children. POPULATION AND METHODS Children were evaluated during the systematic examination that was carried out in nursery school between 3 years and 6 months and 4 years and 6 months of age. 2 investigations were led: investigation of prevalence led in 2660 children and evaluation of performance of the tests in 99 children among them. RESULTS The statistical analyses of their results made it possible to determine scores helping with the decision of a request for assessment to diagnostic aiming. The sensitivity and the specificity of the tests increased with the age and were better within the framework of the tests of language. This new assessment was appreciated by the doctors users.
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Cardiovascular risk estimation in Spanish HIV-infected patients: a multicenter cohort study. J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-p92] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Natural History of Compensated and Decompensated HCV-Related Cirrhosis in HIV-Infected Patients: A Prospective Multicentre Study. Antivir Ther 2007; 12:899-907. [DOI: 10.1177/135965350701200605] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Objective To define the course of HIV-HCV-coinfected patients with compensated and decompensated liver cirrhosis and to investigate the survival and the risk factors for death. Patients and methods Ninety-two HIV-infected patients with HCV-related cirrhosis (50 of them without and 42 with previous decompensations) were prospectively followed up during a median period of 20 months. Clinical, biochemical, virological and immunological factors were analysed. Multivariate analyses were performed of those factors associated with decompensations and mortality. Results There were 168 readmissions due to liver-disease-related causes. A Child-Pugh index ≥6 in those without previous decompensations (hazard ratio [HR] 7.94, 95% confidence interval [CI] 1.59–39.58; P=0.014), and Child-Pugh index ≥9 (HR 2.68, 95% CI 1.13–6.33; P=0.003) and absence of HAART (HR 0.44, 95% CI 0.19–0.98; P=0.048) in those with previous decompensations were independently associated with decompensation during the follow up. There were 27 deaths, 22 of them attributable to liver disease. Independent factors associated with liver-related mortality were a Child-Pugh index ≥9 (HR 6.24, 95% CI 2.31–16.85; P<0.001), progression of Child-Pugh index during the follow up (HR 4.27, 95% CI 1.54–11.80; P=0.008), more than one decompensation (HR 24.25, 95% CI 7.27–40.45; P<0.001) and absence of HAART (HR 0.35, 95% CI 0.12–0.98; P=0.002). Conclusions Evolution from compensated to decompensated cirrhosis and death is influenced by markers of liver function and the absence of HAART. The importance of this last element must be adequately stressed.
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T cell receptor excision circles (TRECs), CD4+, CD8+, and their CD45RO+, and CD45RA+, subpopulations in hepatitis C virus (HCV)-HIV-co-infected patients during treatment with interferon alpha plus ribavirin: analysis in a population on effective antiretroviral therapy. Clin Exp Immunol 2007; 146:270-7. [PMID: 17034579 PMCID: PMC1942067 DOI: 10.1111/j.1365-2249.2006.03220.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Interferon (IFN)-alpha induced CD4(+) T lymphopenia is a toxic effect of the treatment of chronic hepatitis C virus (HCV) in human immunodeficiency virus (HIV)-co-infected patients. To increase the knowledge about this secondary effect, we performed an analysis of the evolution of the T cell receptor excision circles (TRECs), CD4(+) and CD8(+) T cells and of their CD45RO(+) and CD45RA(+) subpopulations during the treatment of chronic hepatitis HCV with peginterferon alpha (pegIFN-alpha) + ribavirin. Twenty HCV/HIV-co-infected patients, with undetectable HIV load after highly active antiretroviral therapy (HAART), were treated with pegIFN-alpha + ribavirin. TRECs were determined using real-time polymerase chain reaction. CD4(+) and CD8(+) T cells and their CD45RO(+) and CD45RA(+) subpopulations were analysed by two-colour flow cytometry. Median baseline CD4(+) and CD8(+) T cells were 592 mm(3) and 874 mm(3), respectively. Median baseline CD45RO(+) subpopulation was 48% for CD4(+) T and 57% for CD8(+) T lymphocytes. A progressive decrease in both T cell populations, as well as of their CD45RO(+) and CD45RA(+) subpopulations, was detected, with a difference between the baseline and nadir levels approaching 50%. The evolution of T cell populations and TRECs was independent of the response to the treatment. T lymphocytes and their subpopulations returned to baseline levels at 24 weeks after the end of treatment, with the exception of the T CD4(+) CD45RA(+) subpopulation. The ratio of CD4(+) CD45RO(+)/CD4(+) CD45RA(+) increased from 0.89 (baseline) to 1.44 (24 weeks after the end of the therapy). TRECs/ml did not return to the basal values. In conclusion, a significant reduction of CD4(+) and CD8(+) T cells, and of their CD45RA(+) and CD45RO(+) subpopulations, in HIV/HCV co-infected patients treated with pegIFN-alpha was observed. Both subpopulations increased after the suppression of treatment, but the CD4(+) CD45RA subpopulation did not reach the basal levels as a consequence, at least in part, of a decrease in thymic production.
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Modifications of haematological series in patients co-infected with human immunodeficiency virus and hepatitis C virus during treatment with interferon and ribavirin: differences between pegylated and standard interferon. Clin Microbiol Infect 2004; 10:1067-74. [PMID: 15606633 DOI: 10.1111/j.1469-0691.2004.01023.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Therapy with interferon and ribavirin for hepatitis C virus (HCV) infection induces a decrease in several haematological population counts. It is unclear whether haematological toxicity is more severe in patients co-infected with HCV and human immunodeficiency virus (HIV). This study analysed the evolution of haematological population counts during and after interferon and ribavirin therapy for chronic HCV infection. Eleven patients co-infected with HIV and HCV and treated with pegylated interferon plus ribavirin, and ten treated with standard interferon plus ribavirin, were analysed. With reference to baseline values, neutrophil counts decreased by an average of 45% (range 18-67%), total lymphocytes by 50% (16-63%), CD4 lymphocytes by 54% (16-61%), haemoglobin by 9% (5-16%) and platelets by 31% (16-45%). The nadir of the decrease was reached in the first weeks of therapy and was maintained while patients were receiving treatment. The reduction in all series was higher with pegylated interferon. Patients recovered their baseline counts after finishing the treatment. No cases of haemorrhage or outstanding infection were detected during follow-up.
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B-13 Contamination microbienne des liquides de conservation des greffons cardiaques et infections chez le transplanté. Med Mal Infect 2004. [DOI: 10.1016/s0399-077x(04)90143-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Cloning of the PpMSH-2 cDNA of Physcomitrella patens, a moss in which gene targeting by homologous recombination occurs at high frequency. Biochimie 2001; 83:1003-8. [PMID: 11879728 DOI: 10.1016/s0300-9084(01)01350-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In the moss Physcomitrella patens integrative transformants from homologous recombination are obtained at an efficiency comparable to that found for yeast. This property, unique in the plant kingdom, allows the knockout of specific genes. It also makes the moss a convenient model to study the regulation of homologous recombination in plants. We used degenerate oligonucleotides designed from AtMSH2 from Arabidopsis thaliana and other known MutS homologues to isolate the P. patens MSH2 (PpMSH2) cDNA. The deduced sequence of the PpMSH2 protein is respectively 60.8% and 59.6% identical to the maize and A. thaliana MSH2. Phylogenic studies show that PpMSH2 is closely related to the group of plant MSH2 proteins. Southern analysis reveals that the gene exists as a single copy in the P. patens genome.
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Abstract
DESIGN Recommendations for triage to intensive care units (ICUs) have been issued but not evaluated. SETTING In this prospective, multicenter study, all patients granted or refused admission to 26 ICUs affiliated with the French Society for Critical Care were included during a 1-month period. Characteristics of participating ICUs and patients, circumstances of triage, and description of the triage decision with particular attention to compliance with published recommendations were recorded. RESULTS During the study period, 1,009 patients were and 283 were not admitted to the participating ICUs. Refused patients were more likely to be older than 65 yrs (odds ratio [OR], 3.53; confidence interval [CI], 1.98-5.32) and to have a poor chronic health status (OR, 3.09; CI, 2.05-4.67). An admission diagnosis of acute respiratory or renal failure, shock, or coma was associated with admission, whereas chronic severe respiratory and heart failure or metastatic disease without hope of remission were associated with refusal (OR, 2.24; CI, 1.38-3.64). Only four (range, 0-8) of the 20 recommendations for triage to ICU were observed; a full unit and triage over the phone were associated with significantly poorer compliance with recommendations (0 [0-2] vs. 6 [2-9], p =.0003; and 1 [0-6] vs. 6 [1-9], p <.0001; respectively). CONCLUSION Recommendations for triage to intensive care are rarely observed, particularly when the unit is full or triage is done over the phone. These recommendations may need to be redesigned to improve their practicability under real-life conditions, with special attention to phone triage and triaging to a full unit.
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Photoaffinity labelling with the cytokinin agonist azido-CPPU of a 34 kDa peptide of the intracellular pathogenesis-related protein family in the moss Physcomitrella patens. PLANT MOLECULAR BIOLOGY 2001; 46:539-48. [PMID: 11516147 DOI: 10.1023/a:1010693213437] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
As in higher plants, the development of the moss Physcomitrella patens is regulated by environmental signals and phytohormones. At the protonema level transition from chloronema to caulonema cells is under auxin control. The formation on second sub-apical caulonema cells of buds that will give rise to the leafy gametophore requires cytokinins. Using [3H]azidoCPPU (1-(2-azido-6-chloropyrid-4-yl)-3-(4-[3H])phenylurea), a photoactivatable cytokinin agonist, we have specifically photolabelled a soluble 34 kDa protein of P. patens. Urea derivatives were very efficient competitors of photolabelling while purine-type cytokinins were poor competitors. The protein UBP34 was purified by affinity chromatography and the sequences of six internal peptides obtained. A cDNA encoding UBP34 was cloned by screening a P. patens protonema cDNA library with a probe amplified by PCR using degenerate primers designed from the peptide sequences. The UBP34 amino acid sequence shows an average sequence identity of 42% with both intracellular PR proteins and the BetV1-related family of plant allergens. Recombinant UBP34 expressed in Escherichia coli was confirmed to bind azidoCPPU.
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Bone metastases from a cerebral and sacral ependymoma. Report of a case. Joint Bone Spine 2001; 67:471-4. [PMID: 11143917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
A case of cerebral and sacral ependymoma revealed by cerebellar syndrome and sciatica in a 68-year-old man is reported. Bone metastases were diagnosed seven months after surgical excision of the brain tumor.
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[MRI and CT of parotid diseases in HIV-positive patients]. JOURNAL DE RADIOLOGIE 1996; 77:483-7. [PMID: 8760615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report five cases of HIV patients with parotid pathology during a period of one year. All patients (4 men and 1 woman between the ages of 32 and 47 years) had a MRI or a CT confirmation of the parotid gland lesion. Three patients exhibited parotid gland cysts, one a nonspecific chronic inflammation and one an enlargement of the parotid gland with some benign lymphoepithelial lesions. Two patients underwent ultrasound-guided fine-needle aspiration biopsy. The cytology examination confirmed the benignity of the lesions. Finally, we expose the clinical management of parotid enlargements in HIV-positive patients.
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Validation of high-performance liquid chromatographic methods on two silica base-deactivated reversed phases for the determination of chloroprocaine and bupivacaine. J Pharm Biomed Anal 1996; 14:1251-9. [PMID: 8818042 DOI: 10.1016/0731-7085(95)01700-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The separation of HPLC of basic drugs on silica-based reversed phases remains a major problem because of the interaction between the residual silanol groups of the silica and the amino function of the drug. This paper describes the validation of HPLC methods for the determination of two injectable solutions of basic drugs (two local anaesthetics, chloroprocaine and bupivacaine), with two commercial base-deactivated reversed phases. These columns improve the chromatographic performances without adding a blocking agent to the mobile phase. With a simple aqueous-organic mobile phase, these base-deactivated reversed phases give high theoretical plate numbers (N) and small tailing factors. The optimized methods show good linearity, precision (RSD < 2%) and accuracy (bias < 2% for dosage forms). The limits of detection and quantitation are lower than the maximal accepted limits for impurities. These methods are currently in routine use in stability studies.
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Isolation of gram-positive rods that resemble but are clearly distinct from Actinomyces pyogenes from mixed wound infections. J Clin Microbiol 1993; 31:1127-35. [PMID: 8501213 PMCID: PMC262891 DOI: 10.1128/jcm.31.5.1127-1135.1993] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Beginning in 1990, gram-positive rods resembling Actinomyces pyogenes were found with increasing frequency in mixed cultures from various infectious processes, most of them from patients with otitis, empyema, pilonidal cysts, perianal abscesses, and decubitus ulcers. Ribotyping and hybridization showed that these gram-positive rods could be divided into five groups not related to known Actinomyces species. Biochemical markers for reliable differentiation into these groups, however, could not be found. Therefore, naming new species is not warranted unless parameters are discovered that allow identification without DNA hybridization. These gram-positive rods have been isolated only in mixed cultures with anaerobes, Staphylococcus aureus, Streptococcus "milleri," enterococci, and gram-negative rods. Their exact role in these possibly synergistic infections needs further investigation.
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Abstract
Salmonella typhi splenic abscesses (SA) are traditionally considered to be a rare complication of typhoid fever (TF). Our prospective study in an extensive series of patients was aimed at demonstrating that the incidence of SA was usually underestimated. Four hundred patients were systematically examined by abdominal ultrasound (US) at the time of proven biological diagnosis of TF, which was the 2nd week of admission. Twenty patients with persistent or recurrent symptoms (despite adequate treatment) or with acute lower thoracic pain were followed by US and CT. In eight patients both imaging modalities revealed anomalies compatible with SA.
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[Benign teratoma of the thyroid in one adult]. Presse Med 1988; 17:820-1. [PMID: 2968570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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[Sampling technics in virologic diagnosis. Isolation of the virus and measurement of antiviral antibodies]. SOINS. CHIRURGIE (PARIS, FRANCE : 1982) 1985:7-9. [PMID: 3851505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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[Post-radiotherapy pericardial effusions. Detection by systematic echocardiography after mediastinal irradiation in Hodgkin's disease]. LA NOUVELLE PRESSE MEDICALE 1979; 8:3062. [PMID: 534177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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