384 research outputs found

    Permissive role for mGlu1 metabotropic glutamate receptors in excitotoxic retinal degeneration

    Get PDF
    Neuroprotection is an unmet need in eye disorders characterized by retinal ganglion cell (RGC) death, such as prematurity-induced retinal degeneration, glaucoma, and age-related macular degeneration. In all these disorders excitotoxicity is a prominent component of neuronal damage, but clinical data discourage the development of NMDA receptor antagonists as neuroprotectants. Here, we show that activation of mGlu1 metabotropic glutamate receptors largely contributes to excitotoxic degeneration of RGCs. Mice at postnatal day 9 were challenged with a toxic dose of monosodium glutamate (MSG, 3g/kg), which caused the death of >70% of Brn-3a+ RGCs. Systemic administration of the mGlu1 receptor negative allosteric modulator (NAM), JNJ16259685 (2.5mg/kg, s.c.), was largely protective against MSG-induced RGC death. This treatment did not cause changes in motor behavior in the pups. We also injected MSG to crv4 mice, which lack mGlu1 receptors because of a recessive mutation of the gene encoding the mGlu1 receptor. MSG did not cause retinal degeneration in crv4 mice, whereas it retained its toxic activity in their wild-type littermates. These findings demonstrate that mGlu1 receptors play a key role in excitotoxic degeneration of RGCs, and encourage the study of mGlu1 receptor NAMs in models of retinal neurodegeneration

    Effects of sex hormones on bronchial reactivity during the menstrual cycle

    Get PDF
    Background: Many asthmatic women complain of symptom exacerbations in particular periods, i.e. during pregnancy and menstrual cycles (perimenstrual asthma: PMA)". The goal of this study was to study the effect of the luteal and follicular phases of the menstrual cycle on bronchial reactivity (BR) in a group of asthmatic women. Methods: For this purpose, 36 pre-menopausal women were enrolled and underwent testing for resting pulmonary function, measurement of the diffusing capacity of the lung for carbon monoxide (DLCO), and airway responsiveness to methacholine in the follicular and luteal phases of their menstrual cycles. We also measured plasma hormone levels and levels of cyclic adenosine monophosphate (cAMP; a mediator of bronchial smooth muscle contraction) and testosterone in induced sputum samples. Results: Our study showed that about 30% of the asthmatic women had decreased PC20FEV1.0 in the follicular phase of menstrual cycle with a significant correlation between PC20FEV1.0 and serum testosterone levels. Moreover, marked increases in sputum testosterone levels (mean = 2.6-fold increase) together with significant increases in sputum cAMP concentrations (mean = 3.6-fold increases) were observed during the luteal phase of asthmatic patients, suggesting that testosterone contributes to the pathophysiology of PMA. We excluded the possibility that testosterone directly inhibits phosphodiesterase (PDE) activity as incubating PDE with testosterone in vitro did not reduce PDE catalytic activity. Conclusions: In conclusion, our data show that PC20FEV1.0 was decreased in the follicular phase of the menstrual cycle in about 30% of women and was associated with lower cAMP levels in sputum samples, which may contribute to bronchoconstriction. Our results also suggest a link between PMA and testosterone levels. However, whether these findings are of clinical significance in terms of the management of asthma or asthma worsening during the menstrual cycle needs further investigation

    Phosphodiesterases S-sulfhydration contributes to human skeletal muscle function

    Get PDF
    The increase in intracellular calcium is influenced by cyclic nucleotides (cAMP and cGMP) content, which rating is governed by phosphodiesterases (PDEs) activity.Despite it has been demonstrated a beneficial effect of PDEs inhibitors in different pathological conditions involving SKM, not much is known on the role exerted by cAMP-cGMP/PDEs axis in human SKM contractility. Here, we show that Ssulfhydration of PDEs modulates human SKM contractility in physiological and pathological conditions. Having previously demonstrated that, in the rare human syndrome Malignant Hyperthermia (MH), there is an overproduction of hydrogen sulfide (H2S) within SKM contributing to hyper-contractility, here we have used MH negative diagnosed biopsies (MHN) as healthy SKM, and MH susceptible diagnosed biopsies (MHS) as a pathological model of SKM hypercontractility. The study has been performed on MHS and MHN human biopsies after diagnosis has been made and on primary SKM cells derived from both MHN and MHS biopsies. Our data demonstrate that in normal conditions PDEs are S-sulfhydrated in both quadriceps' biopsies and primary SKM cells. This post translational modification (PTM) negatively regulates PDEs activity with consequent increase of both cAMP and cGMP levels. In hypercontractile biopsies, due to an excessive H2S content, there is an enhanced Ssulfhydration of PDEs that further increases cyclic nucleotides levels contributing to SKM hyper-contractility. Thus, the identification of a new endogenous PTM modulating PDEs activity represents an advancement in SKM physiopathology understanding

    Measles in Italy: Viral strains and crossing borders

    Get PDF
    In 2017, Italy experienced one of the largest outbreaks of measles in recent years, with 5404 notified cases and 4347 confirmed cases. A further 2029 cases were notified during the first 6 months of 2018, and 1516 of them were laboratory-confirmed. The B3 and D8 genotypes were identified as those responsible for the outbreak. Possible transmission routes can be established by monitoring the circulating measles virus strains in support of the national health authorities to warn people and travellers

    Temporary dense seismic network during the 2016 Central Italy seismic emergency for microzonation studies

    Get PDF
    In August 2016, a magnitude 6.0 earthquake struck Central Italy, starting a devastating seismic sequence, aggravated by other two events of magnitude 5.9 and 6.5, respectively. After the first mainshock, four Italian institutions installed a dense temporary network of 50 seismic stations in an area of 260 km2. The network was registered in the International Federation of Digital Seismograph Networks with the code 3A and quoted with a Digital Object Identifier ( https://doi.org/10.13127/SD/ku7Xm12Yy9 ). Raw data were converted into the standard binary miniSEED format, and organized in a structured archive. Then, data quality and completeness were checked, and all the relevant information was used for creating the metadata volumes. Finally, the 99 Gb of continuous seismic data and metadata were uploaded into the INGV node of the European Integrated Data Archive repository. Their use was regulated by a Memorandum of Understanding between the institutions. After an embargo period, the data are now available for many different seismological studies.Publishedid 1825T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa

    Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia

    Get PDF

    Measurement of the W gamma Production Cross Section in Proton-Proton Collisions at root s=13 TeV and Constraints on Effective Field Theory Coefficients

    Get PDF
    A fiducial cross section for W gamma production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb(-1) of data collected using the CMS detector at the LHC. The W -> e nu and mu nu decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.Peer reviewe

    Performance of the CMS muon trigger system in proton-proton collisions at √s = 13 TeV

    Get PDF
    The muon trigger system of the CMS experiment uses a combination of hardware and software to identify events containing a muon. During Run 2 (covering 2015-2018) the LHC achieved instantaneous luminosities as high as 2 × 10 cm s while delivering proton-proton collisions at √s = 13 TeV. The challenge for the trigger system of the CMS experiment is to reduce the registered event rate from about 40 MHz to about 1 kHz. Significant improvements important for the success of the CMS physics program have been made to the muon trigger system via improved muon reconstruction and identification algorithms since the end of Run 1 and throughout the Run 2 data-taking period. The new algorithms maintain the acceptance of the muon triggers at the same or even lower rate throughout the data-taking period despite the increasing number of additional proton-proton interactions in each LHC bunch crossing. In this paper, the algorithms used in 2015 and 2016 and their improvements throughout 2017 and 2018 are described. Measurements of the CMS muon trigger performance for this data-taking period are presented, including efficiencies, transverse momentum resolution, trigger rates, and the purity of the selected muon sample. This paper focuses on the single- and double-muon triggers with the lowest sustainable transverse momentum thresholds used by CMS. The efficiency is measured in a transverse momentum range from 8 to several hundred GeV

    Search for long-lived particles decaying to jets with displaced vertices in proton-proton collisions at root s=13 Te V

    Get PDF
    A search is presented for long-lived particles produced in pairs in proton-proton collisions at the LHC operating at a center-of-mass energy of 13 TeV. The data were collected with the CMS detector during the period from 2015 through 2018, and correspond to a total integrated luminosity of 140 fb(-1). This search targets pairs of long-lived particles with mean proper decay lengths between 0.1 and 100 mm, each of which decays into at least two quarks that hadronize to jets, resulting in a final state with two displaced vertices. No significant excess of events with two displaced vertices is observed. In the context of R-parity violating supersymmetry models, the pair production of long-lived neutralinos, gluinos, and top squarks is excluded at 95% confidence level for cross sections larger than 0.08 fb, masses between 800 and 3000 GeV, and mean proper decay lengths between 1 and 25 mm.Peer reviewe

    Search for top squark production in fully hadronic final states in proton-proton collisions at root s=13 TeV

    Get PDF
    A search for production of the supersymmetric partners of the top quark, top squarks, is presented. The search is based on proton-proton collision events containing multiple jets, no leptons, and large transverse momentum imbalance. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 137 fb(-1). The targeted signal production scenarios are direct and gluino-mediated top squark production, including scenarios in which the top squark and neutralino masses are nearly degenerate. The search utilizes novel algorithms based on deep neural networks that identify hadronically decaying top quarks and W bosons, which are expected in many of the targeted signal models. No statistically significant excess of events is observed relative to the expectation from the standard model, and limits on the top squark production cross section are obtained in the context of simplified supersymmetric models for various production and decay modes. Exclusion limits as high as 1310 GeVare established at the 95% confidence level on the mass of the top squark for direct top squark production models, and as high as 2260 GeV on the mass of the gluino for gluino-mediated top squark production models. These results represent a significant improvement over the results of previous searches for supersymmetry by CMS in the same final state.Peer reviewe
    • 

    corecore