243 research outputs found

    Genetic deletion of α7 nicotinic acetylcholine receptors induces an age-dependent Alzheimer's disease-like pathology.

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    The accumulation of amyloid-beta peptide (Aβ) and the failure of cholinergic transmission are key players in Alzheimer's disease (AD). However, in the healthy brain, Aβ contributes to synaptic plasticity and memory acting through α7 subtype nicotinic acetylcholine receptors (α7nAChRs). Here, we hypothesized that the α7nAChR deletion blocks Aβ physiological function and promotes a compensatory increase in Aβ levels that, in turn, triggers an AD-like pathology. To validate this hypothesis, we studied the age-dependent phenotype of α7 knock out mice. We found that α7nAChR deletion caused an impairment of hippocampal synaptic plasticity and memory at 12 months of age, paralleled by an increase of Amyloid Precursor Protein expression and Aβ levels. This was accompanied by other classical AD features such as a hyperphosphorylation of tau at residues Ser 199, Ser 396, Thr 205, a decrease of GSK-3β at Ser 9, the presence of paired helical filaments and neurofibrillary tangles, neuronal loss and an increase of GFAP-positive astrocytes. Our findings suggest that α7nAChR malfunction might precede Aβ and tau pathology, offering a different perspective to interpret the failure of anti-Aβ therapies against AD and to find novel therapeutical approaches aimed at restoring α7nAChRs-mediated Aβ function at the synapse

    LTP and memory impairment caused by extracellular A\u3b2 and Tau oligomers is APP-dependent

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    The concurrent application of subtoxic doses of soluble oligomeric forms of human amyloid-beta (oA\u3b2) and Tau (oTau) proteins impairs memory and its electrophysiological surrogate long-term potentiation (LTP), effects that may be mediated by intra-neuronal oligomers uptake. Intrigued by these findings, we investigated whether oA\u3b2 and oTau share a common mechanism when they impair memory and LTP in mice. We found that as already shown for oA\u3b2, also oTau can bind to amyloid precursor protein (APP). Moreover, efficient intra-neuronal uptake of oA\u3b2 and oTau requires expression of APP. Finally, the toxic effect of both extracellular oA\u3b2 and oTau on memory and LTP is dependent upon APP since APP-KO mice were resistant to oA\u3b2- and oTau-induced defects in spatial/associative memory and LTP. Thus, APP might serve as a common therapeutic target against Alzheimer's Disease (AD) and a host of other neurodegenerative diseases characterized by abnormal levels of A\u3b2 and/or Tau

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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    Activation of Serotonin 5-HT7 Receptors Modulates Hippocampal Synaptic Plasticity by Stimulation of Adenylate Cyclases and Rescues Learning and Behavior in a Mouse Model of Fragile X Syndrome

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    We have previously demonstrated that activation of serotonin 5-HT7 receptors (5-HT7R) reverses metabotropic glutamate receptor-mediated long term depression (mGluR-LTD) in the hippocampus of wild-type (WT) and Fmr1 Knockout (KO) mice, a model of Fragile X Syndrome (FXS) in which mGluR-LTD is abnormally enhanced. Here, we have investigated intracellular mechanisms underlying the effect of 5-HT7R activation using patch clamp on hippocampal slices. Furthermore, we have tested whether in vivo administration of LP-211, a selective 5-HT7R agonist, can rescue learning and behavior in Fmr1 KO mice. In the presence of an adenylate cyclase blocker, mGluR-LTD was slightly enhanced in WT and therefore the difference between mGluR-LTD in WT and Fmr1 KO slices was no longer present. Conversely, activation of adenylate cyclase by either forskolin or Pituitary Adenylate Cyclase Activating Polypeptide (PACAP) completely reversed mGluR-LTD in WT and Fmr1 KO. 5-HT7R activation reversed mGluR-LTD in WT and corrected exaggerated mGluR-LTD in Fmr1 KO; this effect was abolished by blockade of either adenylate cyclase or protein kinase A (PKA). Exposure of hippocampal slices to LP-211 caused an increased phosphorylation of extracellular signal regulated kinase (ERK), an intracellular effector involved in mGluR-LTD, in WT mice. Conversely, this effect was barely detectable in Fmr1 KO mice, suggesting that 5-HT7R-mediated reversal of mGluR-LTD does not require ERK stimulation. Finally, an acute in vivo administration of LP-211 improved novel object recognition (NOR) performance in WT and Fmr1 KO mice and reduced stereotyped behavior in Fmr1 KO mice. Our results indicate that mGluR-LTD in WT and Fmr1 KO slices is bidirectionally modulated in conditions of either reduced or enhanced cAMP formation. Activation of 5-HT7 receptors reverses mGluR-LTD by activation of the cAMP/PKA intracellular pathway. Importantly, a systemic administration of a 5-HT7R agonist to Fmr1 KO mice corrected learning deficits and repetitive behavior. We suggest that selective 5-HT7R agonists might become novel pharmacological tools for FXS therapy

    Real-life therapeutic effects of beclomethasone dipropionate/formoterol fumarate/glycopyrronium combined triple therapy in patients with chronic obstructive pulmonary disease

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    Background: The small airway disease has been recognized as a central feature of chronic obstructive pulmonary disease (COPD). Triple fixed combination beclomethasone dipropionate/formoterol fumarate/glycopyrronium (BDP/FF/G) is provided as a pressurized single-dose inhaler based on an extra-fine formulation, which has been approved for patients with COPD experiencing frequent disease exacerbations. Methods: The aim of our real-life single-center observational study was to investigate, in 22 patients with COPD, the effects of BDP/FF/G on lung function, respiratory symptoms, health status, and exacerbation rate. Several clinical and lung functional parameters were evaluated at baseline and after 12 months of treatment with combined inhaled triple therapy. Results: With respect to baseline, after 12 months of treatment with BDP/FF/G, significant changes were recorded with regard to forced expiratory flow at 75% of forced vital capacity (FVC) ( p  < 0.01), forced expiratory flow at 50% of FVC ( p  < 0.01), forced expiratory flow at 25% of FVC ( p  < 0.05), and forced mid-expiratory flow between 25% and 75% of FVC ( p  < 0.01). Moreover, we observed reductions of total resistance ( p  < 0.01), effective resistance ( p  < 0.01), and effective specific resistance ( p  < 0.01). In the same period, residual volume diminished ( p  < 0.01) and forced expiratory volume in 1 s increased ( p  < 0.01). Moreover, in a subgroup of 16 patients, an enhancement of diffusion lung capacity ( p  < 0.01) was also detected. These functional results were paralleled by concomitant clinical effects, as evidenced by the improvements of modified British Medical Research Council (mMRC) dyspnea scale ( p  < 0.001), COPD Assessment Test (CAT) score ( p  < 0.0001), and COPD exacerbations ( p  < 0.0001). Conclusion: In conclusion, the valuable findings of our observational study consist in the corroboration in a real-life context of the therapeutic effects evidenced by randomized controlled trials with regard to the use of the triple inhaled BDP/FF/G therapy in patients with COPD

    D4.1 - Analisi dettagliata dei requisiti dei casi d'uso

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    Scopo del presente documento è quello di fornire una descrizione dettagliata degli “use case” già identificati in fase di preparazione della proposta progettuale, inclusiva di un’analisi dei loro requisiti in termini di infrastruttura necessaria per la loro implementazione. A questo proposito, con riferimento a Technopedia2 e alla tassonomia introdotta da IEEE Computer Society, è stata elaborata una tassonomia di tutti i possibili requisiti dei casi d’uso del progetto già identificati. Lo schema del documento è il seguente. La Sezione 2 introduce la metodologia e l’analisi dei requisiti dei casi d’uso. I lemmi della tassonomia sono riportati nella in quella Sezione e sono poi riassunti per completezza nell’Appendice 1, nella quale ad ogni lemma è associato un codice numerico che è quello poi usato come riferimento nelle Sezioni successive del presente documento. La Sezione 3 presenta il modello di definizione dei casi d’uso in termini dei loro Scenari implementativi che sono poi dettagliati nelle Appendici 2-8. Le Sezioni che vanno dalla 4 alla 10 descrivono infine i 7 “use case” che sono stati già identificati. Per ciascuno di essi, l’informazione fornita è declinata sui seguenti aspetti: introduzione e stato dell’arte; descrizione; rilevanza; requisiti in termini di infrastruttura; prodotti attesi; indicatori di prestazione chiave e analisi dei rischi, che sono trattati in altrettante sotto-sezioni

    Correction to: Tocilizumab for patients with COVID-19 pneumonia. The single-arm TOCIVID-19 prospective trial

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