537 research outputs found

    Klebsiella pneumoniae-OMVs activate death-signaling pathways in Human Bronchial Epithelial Host Cells (BEAS-2B)

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    : The programmed cell death pathways of apoptosis are important in mammalian cellular protection from infections. The activation of these pathways depends on the presence of membrane receptors that bind bacterial components to activate the transduction mechanism. In addition to bacteria, these mechanisms can be activated by outer membrane vesicles (OMVs). OMVs are spherical vesicles of 20-250 nm diameter, constitutively released by Gram-negative bacteria. They contain several bacterial determinants including proteins, DNA/RNA and proteins, that activate different cellular processes in host cells. This study focused on Klebsiella pneumoniae-OMVs in activating death mechanisms in human bronchial epithelial cells (BEAS-2B). Characterization of purified OMVs was achieved by scanning electron microscopy, nanoparticle tracking analysis and protein profiling. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay while apoptotic induction was measured by flow cytometry and confirmed by western blotting. The OMVs produced showed a spherical morphology, with a diameter of 137.2 Ā± 41 nm and a vesicular density of 7.8 Ć— 109 particles/mL Exposure of cell monolayers to 50 Ī¼g of K. pneumoniae-OMV for 14 h resulted in approximately 25 % cytotoxicity and 41.15-41.14 % of cells undergoing early and late apoptosis. Fluorescence microscopy revealed reduced cellular density, the presence of apoptotic bodies, chromatin condensation, and nuclear membrane blebbing in residual cells. Activation of caspases -3 and -9 and dysregulation of BAX, BIM and Bcl-xL indicated the activation of mitochondria-dependent apoptosis. Furthermore, a decrease in the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase involved endoplasmic reticulum stress with the potential formation of reactive oxygen species. These findings provide evidence for the role of OMVs in apoptosis and involvement in the pathogenesis of K. pneumoniae infections

    Antimicrobial and antibiofilm activities of new synthesized Silver Ultra-NanoClusters (SUNCs) against Helicobacter pylori

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    Helicobacter pylori colonizes approximately 50% of the world\u2019s population and it is the cause of chronic gastritis, peptic ulcer disease and gastric cancer. The increase of antibiotic resistance is one of the biggest challenges of our century due to its constant increase. In order to identify an alternative or adjuvant strategy to the standard antibiotic therapy, the in vitro activity of newly synthesized Silver Ultra-NanoClusters (SUNCs), characterized by an average size inferior to 5 nm, against clinical strains of Helicobacter pylori, with different antibiotic susceptibilities, was evaluated in this study. MICs and MBCs were determined by the broth microdilution method, whereas the effect of drug combinations by the checkerboard assay. The Minimum Biofilm Eradication Concentration (MBEC) was measured using AlamarBlue (AB) assay and Colony Forming Unit (CFU) counts. The cytotoxicity was evaluated by performing the MTT assay on AGS cell line. The inhibitory activity was expressed in terms of bacteriostatic and bactericidal potential, with MIC50, MIC90, and MBC50 of 0.33 mg/L against planktonic Helicobacter pylori strains. Using the fractional inhibitory concentration index, SUNCs showed synergism with metronidazole in one clinical strain, and very close to synergistic effect on the reference strain; the combination with clarythromicin evidenced an effect very close to synergism on both strains considered. The biofilm eradication was obtained after treatment with 2X, 3X and 4X MIC value. Moreover, SUNCs showed low toxicity on human cells and was effective in eradicating a mature biofilm produced by H. pylori. The data presented in this study demonstrate that SUNCs could represent a novel strategy for the treatment of H. pylori infections either alone or in combination with metronidazole

    A Multivariate Analysis of Depression Prevalence in Psoriasis Patients: A Cohort Study

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    The literature reported higher depression rates in psoriasis patients compared to the general population. Our study aimed to verify whether variability in depression prevalence was due to using different diagnostic tools. We also aimed to determine whether dysfunctional coping strategies might increase the depression burden. We assessed psoriasis severity by the Psoriasis Area Severity Index (PASI) and PSOdisk. We analyzed mental alterations of 120 outpatients by Hamilton Depression and Anxiety Rating Scales (HAM-D and HAM-A), Symptom Checklist-90-Revised (SCL-90-R), plus coping strategies and quality of life by Coping Orientation to Problems Experienced (COPE) Inventory and 36-Item Short Form Health Survey (SF-36). We divided our cohort into five subgroups from minimal to severe psoriasis using the PSOdisk total score. Depression prevalence varied according to the assessment criteria for specificity, frequency, and severity. Different mood disorders other than major depression emerged when we used DSM-IV-TR criteria. Correlation analysis of the criteria we used to diagnose depression or depressed mood indicated that a dysfunctional coping strategy was highly and positively correlated only in patients of the severe subgroup. Differently, a negative correlation emerged between the SF-36 Mental Summary Component (MSC) and behavioral disengagement, thus suggesting that psychopathological distress might induce patients with a marked/severe psoriasis to adopt dysfunctional coping strategies. Dermatologists are fundamental in detecting comorbid depression, referring psoriasis patients to mental health specialists to achieve adequate treatments, and preventing suicide risk

    Ankyrin-B Syndrome: Enhanced Cardiac Function Balanced by Risk of Cardiac Death and Premature Senescence

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    Here we report the unexpected finding that specific human ANK2 variants represent a new example of balanced human variants. The prevalence of certain ANK2 (encodes ankyrin-B) variants range from 2 percent of European individuals to 8 percent in individuals from West Africa. Ankyrin-B variants associated with severe human arrhythmia phenotypes (eg E1425G, V1516D, R1788W) were rare in the general population. Variants associated with less severe clinical and in vitro phenotypes were unexpectedly common. Studies with the ankyrin-B+/āˆ’ mouse reveal both benefits of enhanced cardiac contractility, as well as costs in earlier senescence and reduced lifespan. Together these findings suggest a constellation of traits that we term ā€œankyrin-B syndromeā€, which may contribute to both aging-related disorders and enhanced cardiac function

    Safety of mRNA COVID-19 Vaccines in Patients with Inborn Errors of Immunity: an Italian Multicentric Study

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    Purpose: Little is known about vaccine safety in inborn errors of immunity (IEI) patients during the current vaccination campaign for COVID-19. To better investigate the reactogenicity and adverse event profile after two, three, and four doses of mRNA vaccines, we conducted an observational, multicentric study on 342 PID patients from four Italian Referral Centres. Methods: We conducted a survey on self-reported adverse reactions in IEI patients who received mRNA vaccine by administering a questionnaire after each dose. Results: Over the whole study period, none of the patients needed hospitalization or had hypersensitivity reactions, including anaphylaxis and delayed injection site reaction. After two vaccination doses, 35.4% of patients showed only local reactogenicity-related symptoms (RrS), 44.4% reported both systemic and local RrS, and 5% reported only systemic RrS. In more than 60% of cases, local or systemic RrS were mild. After the first and second booster doses, patients showed fewer adverse events (AEs) than after the first vaccination course. Patients aged 50 years and older reported adverse events and RrS less frequently. Among AEs requiring treatment, one common variable immune deficiency patient affected by T cell large granular lymphocytic leukemia developed neutropenia and one patient had Bellā€™s paralysis perhaps during herpes zoster reactivation. Conclusion: Although our follow-up period is relatively short, the safety data we reported are reassuring. This data would help to contrast the vaccine hesitancy often manifested by patients with IEI and to better inform their healthcare providers

    A Genome-Wide Screening and SNPs-to-Genes Approach to Identify Novel Genetic Risk Factors Associated with Frontotemporal Dementia

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    Frontotemporal dementia (FTD) is the second most prevalent form of early onset dementia after Alzheimerā€™s disease (AD). We performed a case-control association study in an Italian FTD cohort (n = 530) followed by the novel SNPs-to-genes approach and functional annotation analysis. We identified two novel potential loci for FTD. Suggestive SNPs reached p-values ~10-7 and OR > 2.5 (2p16.3) and 1.5 (17q25.3). Suggestive alleles at 17q25.3 identified a disease-associated haplotype causing decreased expression of -cis genes such as RFNG and AATK involved in neuronal genesis and differentiation, and axon outgrowth, respectively. We replicated this locus through the SNPs-to-genes approach. Our functional annotation analysis indicated significant enrichment for functions of the brain (neuronal genesis, differentiation and maturation), the synapse (neurotransmission and synapse plasticity), and elements of the immune system, the latter supporting our recent international FTD-GWAS. This is the largest genome-wide study in Italian FTD to date. Although our results are not conclusive, we set the basis for future replication studies and identification of susceptible molecular mechanisms involved in FTD pathogenesis

    Lack of replication of genetic associations with human longevity

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    The exceptional longevity of centenarians is due in part to inherited genetic factors, as deduced from data that show that first degree relatives of centenarians live longer and have reduced overall mortality. In recent years, a number of groups have performed genetic association studies on long-living individuals (LLI) and young controls to identify alleles that are either positively or negatively selected in the centenarian population as consequence of a demographic pressure. Many of the reported studies have shown genetic loci associated with longevity. Of these, with the exception of APOE, none have been convincingly reproduced. We validated our populations by typing the APOE locus. In addition, we used 749 American Caucasian LLI, organized in two independent tiers and 355 American Caucasian controls in the attempt to replicate previously published findings. We tested Klotho (KL)-VS variant (rs952706), Cholesteryl Ester Transfer Protein (CETP) I405V (rs5882), Paraoxonase 1 (PON1) Q192R (rs662), Apolipoprotein C-III (APOC3) -641C/A (rs2542052), Microsomal Transfer Protein (MTP) -493G/T (rs2866164) and apolipoprotein E (APOE) epsilon2 and epsilon4 isoforms, (rs7412 and rs429358) haplotypes respectively. Our results show that, at present, except for APOE, none of the selected genes show association with longevity if carefully tested in a large cohort of LLI and their controls, pointing to the need of larger populations for case-control studies in extreme longevity

    A Complete Meteo/Hydro/Hydraulic Chain Application to Support Early Warning and Monitoring Systems: The Apollo Medicane Use Case

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    Because of the ongoing changing climate, extreme rainfall eventsā€™ frequency at the global scale is expected to increase, thus resulting in high social and economic impacts. A Meteo/Hydro/Hydraulic forecasting chain combining heterogeneous observational data sources is a crucial component for an Early Warning System and is a fundamental asset for Civil Protection Authorities to correctly predict these events, their effects, and put in place anticipatory actions. During the last week of October 2021 an intense Mediterranean hurricane (Apollo) affected many Mediterranean countries (Tunisia, Algeria, Malta, and Italy) with a death toll of seven people. The CIMA Meteo/Hydro/Hydraulic forecasting chain, including the WRF model, the hydrological model Continuum, the automatic system for water detection (AUTOWADE), and the hydraulic model TELEMAC-2D, was operated in real-time to predict the Apollo weather evolution as well as its hydrological and hydraulic impacts, in support of the early warning activities of the Italian Civil Protection Department. The WRF model assimilating radar data and in situ weather stations showed very good predictive capability for rainfall timing and location over eastern Sicily, thus supporting accurate river flow peak forecasting with the hydrological model Continuum. Based on WRF predictions, the daily automatic system for water detection (AUTOWADE) run using Sentinel 1 data was anticipated with respect to the scheduled timing to quickly produce a flood monitoring map. Ad hoc tasking of the COSMO-SkyMed satellite constellation was also performed to overcome the S1 data latency in eastern Sicily. The resulting automated operational mapping of floods and inland waters was integrated with the subsequent execution of the hydraulic model TELEMAC-2D to have a complete representation of the flooded area with water depth and water velocity
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