211 research outputs found

    Hormone-regulated expression and distribution of versican in mouse uterine tissues

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination.</p> <p>Methods</p> <p>Uteri from mice in all phases of the estrous cycle, and animals subjected to ovariectomy and hormone replacement were collected for immunoperoxidase staining for versican, as well as PCR and quantitative Real Time PCR.</p> <p>Results</p> <p>In diestrus and proestrus, VER was exclusively expressed in the endometrial stroma. In estrus and metaestrus, VER was present in both endometrial stroma and myometrium. In OVX mice, VER immunoreaction was abolished in all uterine tissues. VER expression was restored by E2, MPA and E2+MPA treatments. Real Time PCR analysis showed that VER expression increases considerably in the MPA-treated group. Analysis of mRNA identified isoforms V0, V1 and V3 in the mouse uterus.</p> <p>Conclusion</p> <p>These results show that the expression of versican in uterine tissues is modulated by ovarian steroid hormones, in a tissue-specific manner. VER is induced in the myometrium exclusively by E2, whereas MPA induces VER deposition only in the endometrial stroma.</p

    A new approach to bacterial colony morphotyping by matrix-assisted laser desorption ionization time of flight-based mass spectrometry

    Get PDF
    Matrix assisted laser desorption ionization time of flight mass spectrometry has been explored as a tool to bacterial colony morphotyping.To this end,four colony morphotypes of Pseudomonas aeruginosa and four of Staphylococcus aureus were analysed using intact bacteria.Results suggest that mass spectrometry of intact bacteria could,in some extent,be used to complement the classical morphological classification of bacteria.Financial support from IBB-CEB and Fundacao para a Ciencia e Tecnologia (FCT) and European Community fund FEDER, through Program COMPETE, in the ambit of the FCT project "PTDC/SAU-SAP/113196/2009/ FCOMP-01-0124-FEDER-016012" and Ana Margarida Sousa PhD grant (SFRH/BD/72551/2010), is gratefully acknowledged. Authors also thank Portugal-Spain cooperation action sponsored by the Foundation of Portuguese Universities [E 48/11] and the Spanish Ministry of Science and Innovation [AIB2010PT-00353]

    Mass-Up and Decision Peptide-Driven: two open-source applications for MALDI-TOF MS data analysis and protein quantification

    Get PDF
    Poster presentation at EUBIC Winter School 2017 (10th - 13th January 2017, Sporthotel Semmering, Austria)

    Optical and Near Infrared Monitoring of the Black-Hole X-ray Binary GX 339-4 During 2002-2010

    Get PDF
    We present the optical/infra-red lightcurve (O/IR) of the black hole X-ray binary GX 339-4 collected at the SMARTS 1.3m telescope from 2002 to 2010. During this time the source has undergone numerous state transitions including hard-to-soft state transitions when we see large changes in the near-IR flux accompanied by modest changes in optical flux, and three rebrightening events in 2003, 2005 and 2007 after GX 339-4 transitioned from the soft state to the hard. All but one outburst show similar behavior in the X-ray hardness-intensity diagram. We show that the O/IR colors follow two distinct tracks that reflect either the hard or soft X-ray state of the source. Thus, either of these two X-ray states can be inferred from O/IR observations alone. From these correlations we have constructed spectral energy distributions of the soft and hard states. During the hard state, the near-IR data have the same spectral slope as simultaneous radio data when GX 339-4 was in a bright optical state, implying that the near-IR is dominated by a non-thermal source, most likely originating from jets. Non-thermal emission dominates the near-IR bands during the hard state at all but the faintest optical states, and the fraction of non-thermal emission increases with increasing optical brightness. The spectral slope of the optical bands indicate that a heated thermal source is present during both the soft and hard X-ray states, even when GX 339-4 is at its faintest optical state. We have conducted a timing analysis of the light curve for the hard and soft states and find no evidence of a characteristic timescale within the range of 4-230 days.Comment: Accepted for publication in AJ, Table 3 can be viewed at http://www.astro.yale.edu/buxton/GX339

    TEMPus VoLA: The timed Epstein multi-pressure vessel at low accelerations.

    Get PDF
    The field of planetary system formation relies extensively on our understanding of the aerodynamic interaction between gas and dust in protoplanetary disks. Of particular importance are the mechanisms triggering fluid instabilities and clumping of dust particles into aggregates, and their subsequent inclusion into planetesimals. We introduce the timed Epstein multi-pressure vessel at low accelerations, which is an experimental apparatus for the study of particle dynamics and rarefied gas under micro-gravity conditions. This facility contains three experiments dedicated to studying aerodynamic processes: (i) the development of pressure gradients due to collective particle-gas interaction, (ii) the drag coefficients of dust aggregates with variable particle-gas velocity, and (iii) the effect of dust on the profile of a shear flow and resultant onset of turbulence. The approach is innovative with respect to previous experiments because we access an untouched parameter space in terms of dust particle packing fraction, and Knudsen, Stokes, and Reynolds numbers. The mechanisms investigated are also relevant for our understanding of the emission of dust from active surfaces, such as cometary nuclei, and new experimental data will help interpreting previous datasets (Rosetta) and prepare future spacecraft observations (Comet Interceptor). We report on the performance of the experiments, which has been tested over the course of multiple flight campaigns. The project is now ready to benefit from additional flight campaigns, to cover a wide parameter space. The outcome will be a comprehensive framework to test models and numerical recipes for studying collective dust particle aerodynamics under space-like conditions

    Complete proteome of a quinolone-resistant Salmonella Typhimurium phage type DT104B clinical strain

    Get PDF
    Salmonellosis is one of the most common and widely distributed foodborne diseases. The emergence of Salmonella strains that are resistant to a variety of antimicrobials is a serious global public health concern. Salmonella enterica serovar Typhimurium definitive phage type 104 (DT104) is one of these emerging epidemic multidrug resistant strains. Here we collate information from the diverse and comprehensive range of experiments on Salmonella proteomes that have been published. We then present a new study of the proteome of the quinolone-resistant Se20 strain (phage type DT104B), recovered after ciprofloxacin treatment and compared it to the proteome of reference strain SL1344. A total of 186 and 219 protein spots were recovered from Se20 and SL1344 protein extracts, respectively, after two-dimensional gel electrophoresis. The signatures of 94% of the protein spots were successfully identified through matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS). Three antimicrobial resistance related proteins, whose genes were previously detected by polymerase chain reaction (PCR), were identified in the clinical strain. The presence of these proteins, dihydropteroate synthase type-2 (sul2 gene), aminoglycoside resistance protein A (strA gene) and aminoglycoside 6'-N-acetyltransferase type Ib-cr4 (aac(6')-Ib-cr4 gene), was confirmed in the DT104B clinical strain. The aac(6')-Ib-cr4 gene is responsible for plasmid-mediated aminoglycoside and quinolone resistance. This is a preliminary analysis of the proteome of these two S. Typhimurium strains and further work is being developed to better understand how antimicrobial resistance is developing in this pathogen

    Magneto-Fluorescent Mesoporous Nanocarriers for the Dual-Delivery of Ofloxacin and Doxorubicin to Tackle Opportunistic Bacterial Infections in Colorectal Cancer

    Get PDF
    Funding Information: This work was funded by the Associate Laboratory for Green Chemistry—LAQV which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020) as well as the Scientific Society PROTEOMASS (Portugal) for funding support (General Funding Grant 2021). G.M thanks to FCT/MEC (Portugal) for his doctoral grant PD/BD/142865/2018. E.O thanks FCT/MEC (Portugal) for the individual contract, CEECIND/00648/2017. This work was also funded by FCT—Foundation for Science and Technology, I.P., through projects UIDB/04077/2020, UIDP/04077/2020, OrMagNa—PTDC/NAN-MAT/28785/2017, BioISI—UID/Multi/04046/2019, UIDB/04046/2020 and UIDP/04046/2020 Centre grants (BioISI) and NECL infrastructure. Publisher Copyright: © 2022 by the authors.Cancer-related opportunistic bacterial infections are one major barrier for successful clinical therapies, often correlated to the production of genotoxic factors and higher cancer incidence. Although dual anticancer and antimicrobial therapies are a growing therapeutic fashion, they still fall short when it comes to specific delivery and local action in in vivo systems. Nanoparticles are seen as potential therapeutic vectors, be it by means of their intrinsic antibacterial properties and effective delivery capacity, or by means of their repeatedly reported modulation and maneuverability. Herein we report on the production of a biocompatible, antimicrobial magneto-fluorescent nanosystem (NANO3) for the delivery of a dual doxorubicin–ofloxacin formulation against cancer-related bacterial infections. The drug delivery capacity, rendered by its mesoporous silica matrix, is confirmed by the high loading capacity and stimuli-driven release of both drugs, with preference for tumor-like acidic media. The pH-dependent emission of its surface fluorescent SiQDs, provides an insight into NANO3 surface behavior and pore availability, with the SiQDs working as pore gates. Hyperthermia induces heat generation to febrile temperatures, doubling drug release. NANO3-loaded systems demonstrate significant antimicrobial activity, specifically after the application of hyperthermia conditions. NANO3 structure and antimicrobial properties confirm their potential use in a future dual anticancer and antimicrobial therapeutical vector, due to their drug loading capacity and their surface availability for further modification with bioactive, targeting species.publishersversionpublishe

    Disentangling cosmic-ray and dark-matter induced gamma-rays in galaxy clusters?

    Full text link
    Galaxy clusters are among the best targets for indirect dark matter detection in gamma-rays, despite the large astrophysical background expected from these objects. Detection is now within reach of current observatories (Fermi-LAT or Cerenkov telescopes); however, assessing the origin of this signal might be difficult. We investigate whether the behaviour of the number of objects per `flux' bin (logN-logF) and that of the stacked signal could be used as a signature of the dominant process at stake.We use the CLUMPY code to integrate the signal from decaying or annihilating dark matter and cosmic rays along the line of sight. We assume the standard NFW profile for the dark matter density and rely on a parametrised emissivity for the cosmic-ray component. In this context, the consequences of stacking are explored using the MCXC meta-catalogue of galaxy clusters. We find the value of the slope of the logN-logF power law (or the increase of the signal with the number of stacked objects) to be a clear diagnosis to disentangle decaying dark matter from cosmic-ray induced gamma-rays. For dark matter annihilation, depending on the signal boost from the substructures, it is either similar to the cosmic-ray signal (no boost) or similar to the decay case (large boosts). The shift between the brightest object and its followers also depends on the signal origin. For annihilation, this shift and the stacked signal are poorly constrained because of the large uncertainty affecting the boost. We also underline that the angular dependence of the annihilation signal is not universal because of the substructure contribution.Comment: 7 pages, 3 figures, minor corrections (to match the A&A accepted version

    A tutorial

    Get PDF
    PM003/2016. Publisher Copyright: © 2022 The Author(s)The capabilities of bioanalytical mass spectrometry to (i) detect and differentiate viruses at the peptide level whilst maintaining high sample throughput and (ii) to provide diagnosis and prognosis for infected patients are presented as a tutorial in this work to aid analytical chemists and physicians to gain insights into the possibilities offered by current high-resolution mass spectrometry technology and bioinformatics. From (i) sampling to sample treatment; (ii) Matrix-Assisted Laser Desorption Ionization- to Electrospray Ionization -based mass spectrometry; and (iii) from clustering to peptide sequencing; a detailed step-by-step guide is provided and exemplified using SARS-CoV-2 Spike Y839 variant and the variant of concern SARS-CoV-2 Alpha (B.1.1.7 lineage), Influenza B, and Influenza A subtypes AH1N1pdm09 and AH3N2.publishersversionpublishe

    A population of luminous accreting black holes with hidden mergers

    Full text link
    Major galaxy mergers are thought to play an important part in fuelling the growth of supermassive black holes. However, observational support for this hypothesis is mixed, with some studies showing a correlation between merging galaxies and luminous quasars and others showing no such association. Recent observations have shown that a black hole is likely to become heavily obscured behind merger-driven gas and dust, even in the early stages of the merger, when the galaxies are well separated (5 to 40 kiloparsecs). Merger simulations further suggest that such obscuration and black-hole accretion peaks in the final merger stage, when the two galactic nuclei are closely separated (less than 3 kiloparsecs). Resolving this final stage requires a combination of high-spatial-resolution infrared imaging and high-sensitivity hard-X-ray observations to detect highly obscured sources. However, large numbers of obscured luminous accreting supermassive black holes have been recently detected nearby (distances below 250 megaparsecs) in X-ray observations. Here we report high-resolution infrared observations of hard-X-ray-selected black holes and the discovery of obscured nuclear mergers, the parent populations of supermassive-black-hole mergers. We find that obscured luminous black holes (bolometric luminosity higher than 2x10^44 ergs per second) show a significant (P<0.001) excess of late-stage nuclear mergers (17.6 per cent) compared to a sample of inactive galaxies with matching stellar masses and star formation rates (1.1 per cent), in agreement with theoretical predictions. Using hydrodynamic simulations, we confirm that the excess of nuclear mergers is indeed strongest for gas-rich major-merger hosts of obscured luminous black holes in this final stage.Comment: To appear in the 8 November 2018 issue of Nature. This is the authors' version of the wor
    • …
    corecore