13 research outputs found

    HadA is an atypical new multifunctional trimeric coiled-coil adhesin of Haemophilus influenzae biogroup aegyptius, which promotes entry into host cells.

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    Summary The Oca (Oligomeric coiled-coil adhesin) family is a subgroup of the bacterial trimeric autotrans- porter adhesins, which includes structurally related proteins, such as YadA of Yersinia entero- colitica and NadA of Neisseria meningitidis. In this study, we searched in silico for novel members of this family in bacterial genomes and identified HadA (Haemophilus adhesin A), a trimeric autotransporter expressed only by Haemophilus influenzae biogroup aegyptius causing Brazilian purpuric fever (BPF), a fulminant septicemic disease of children. By comparative genomics and sequence analysis we predicted that the hadA gene is harboured on a mobile genetic element unique to BPF isolates. Biological analysis of HadA in the native background was limited because this organism is not amenable to genetic manipulation. Alternatively, we demonstrated that expression of HadA confers to a non-invasive Escherichia coli strain the ability to adhere to human cells and to extracellular matrix proteins and to induce in vitro bacterial aggregation and microcolony formation. Intriguingly, HadA is pre- dicted to lack the typical N-terminal head domain of Oca proteins generally associated with cellular receptor binding. We propose here a structural model of the HadA coiled-coil stalk and show that the N-terminal region is still responsible of the binding activity and a KGD motif plays a role. Interestingly, HadA promotes bacterial entry into mammalian cells. Our results show a cytoskeleton re-arrangement and an involvement of clathrin in the HadA-mediated internalization. These data give new insights on the structure-function relationship of oligomeric coiled-coil adhesins and suggest a potential role of this protein in the pathogenesis of BPF

    Be social, be agile: team engagement with Redmine

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    System engineering and project-team management are essential tools to ensure the project success and the Redmine is a valuable platform for the work organization and for a system engineered approach. We review in this work the management needs related to our project, and suggest the possibility that they fit to many research activities with a similar scenario: small team, technical difficulties (or unknowns), intense activity sprints and long pauses due to external schedule management, a large degree of shared leadership. We will then present our implementation with the Redmine, showing that the use of the platform resulted in a strong engagement and commitment of the team. The explicit goal of this work is also to rise, at least internally, the awareness about team needs and available organizational tools and methods; and to highlight a shareable approach to team management and small scale system engineering

    Evaluation of the in vitro activity of ceftobiprole against clinical isolates of Staphylococcus aureus

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    Background and aims: Ceftobiprole is a new cephalosporin characterized by a potent activity against Gram-positive and Gram-negative bacterial pathogens. It is noting that ceftobiprole has a strong affinity for penicillin binding proteins including PBP 2A, which mediates resistance to beta-lactams in methicillin (oxacillin)-resistant coagulase- negative staphylococci and Staphylococcus aureus (MRSA). The aim of the current study was to examine the antimicrobial activity of ceftobiprole against clinical isolates of S. aureus recently collected at our institution. Materials and methods: One hundred and forty blood isolates of S. aureus were evaluated, including methicillin-susceptible (MSSA, n=70) and MRSA (n=70) strains. Twenty additional MRSA isolates obtained from different sites (including skin and soft tissues, blood, and lower respiratory tract) and characterized by borderline susceptibility to vancomycin were also studied to assess the ability of ceftobiprole to overcome this worrisome trait. MIC values of ceftobiprole were determined by Etest strips and results were interpreted according to EUCAST guidelines. Results and conclusions: Study isolates were consistently susceptible to ceftobiprole, with MIC values ranging from 0.125 mg/L to 2 mg/L. Overall, MIC50 and MIC90 were 0.25 mg/L and 0.5 mg/L, respectively. Ceftobiprole showed in vitro activity against all S. aureus isolates, with small differences among groups selected on the basis of resistance to methicillin and/or reduced susceptibility to vancomycin. Thus, ceftobiprole appears a valid choice for treating infections caused by S. aureus, even when susceptibility results are not yet available. Additionally, ceftobiprole may be a valid option in the case of reduced susceptibility to vancomycin

    Perceived Anxiety, Coping, and Autonomic Function in Takotsubo Syndrome Long after the Acute Event

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    Background: Anxiety and depressive disorders represent predisposing factors for the autonomic dysfunctions that characterize the acute phase of Takotsubo syndrome (TS). However, there is insufficient data on this relationship after the acute event. The present study aimed at evaluating the psychological and autonomic status of patients with a history of TS. Methods: Ten TS patients whose acute event occurred at least 1 year prior to the evaluation and nine healthy age- and sex-matched subjects were evaluated. The cardiovascular assessment included a clinical examination, beat-to-beat heart rate monitoring to assess heart rate variability, and a psychological examination using the 16 Personality Factors-C Form (16PF), the Acceptance and Action Questionnaire-II, the Coping Orientations to Problems Experienced (COPE), the Beck Depression Inventory-II, and the State-Trait Anxiety Inventory (STAI). Results: TS patients scored significantly higher on the STAI (i.e., Anxiety Trait), 16PF (i.e., Tension), and COPE (i.e., Transcendental Orientation). TS patients also showed lower heart rate variability. Moreover, a significant inverse correlation was found between sympathetic tone (LF/HF ratio) and coping orientation. Conclusions: Long after the acute event, TS patients are characterized by elevated anxiety, high tension, and a specific religious coping strategy

    Fire-smart solutions for sustainable wildfire risk prevention: Bottom-up initiatives meet top-down policies under EU green deal

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    Fuel management for wildfire risk prevention generally lacks economic sustainability. In marginal areas of southern Europe, this limits fuel treatment programs from reaching the critical mass of required treated area to modify landscape flammability, the fire regime and its impacts. This study investigates key fuel management initiatives for wildfire risk prevention in southern EU countries. We compared local approaches through a bottom-up selection of 38 initiatives, which we analyzed systematically through a set of fire-smart criteria: sustainability, cost-benefit ratio, synergies and inter-sectoral cooperation, integration between strategic prevention planning and multiple land governance goals (e.g., rural development, biodiversity conservation, energy supply), innovation and knowledge transfer, and adaptive management. We summarized lessons learned from the most innovative initiatives, by identifying solutions and functional approaches for building sustainable fuel management at the landscape scale, under fire-smart management principles. These make synergistic use of private, public and European resources to activate value chains that valorize the products, by-products and services generated by fuel management activities and their positive externalities on ecosystem services. The multiple mechanisms include fire-marketing, Payment for Ecosystem Services schemes, specific taxes, or environmental compensatory measures. These mechanisms catalyze the interest of multiple stakeholders (economic actors, private owners, land and fire management agencies) improving the cost-efficiency of landscape fuel management. We contend that the EU Green Deal offers the political backing and framework (mainstreaming of EU strategies and funding opportunities) to enable the replication of documented fire-smart models and functional approaches to wildfire risk prevention.17s

    Quantitative Detection of Epstein-Barr Virus DNA in Cerebrospinal Fluid and Blood Samples of Patients with Relapsing-Remitting Multiple Sclerosis

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    <div><p>The presence of Epstein-Barr Virus (EBV) DNA in cerebrospinal fluid (CSF) and peripheral blood (PB) samples collected from 55 patients with clinical and radiologically-active relapsing-remitting MS (RRMS) and 51 subjects with other neurological diseases was determined using standardized commercially available kits for viral nucleic acid extraction and quantitative EBV DNA detection. Both cell-free and cell-associated CSF and PB fractions were analyzed, to distinguish latent from lytic EBV infection. EBV DNA was detected in 5.5% and 18.2% of cell-free and cell-associated CSF fractions of patients with RRMS as compared to 7.8% and 7.8% of controls; plasma and peripheral blood mononuclear cells (PBMC) positivity rates were 7.3% and 47.3% versus 5.8% and 31.4%, respectively. No significant difference in median EBV viral loads of positive samples was found between RRMS and control patients in all tested samples. Absence of statistically significant differences in EBV positivity rates between RRMS and control patients, despite the use of highly sensitive standardized methods, points to the lack of association between EBV and MS disease activity.</p></div

    EBV <i>EBNA-1</i> gene prevalence and viral loads in CSF and blood samples of 55 RRMS and 51 controls (OIND + NIND) patients.

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    <p>PBMC  =  peripheral blood mononuclear cells; CSF  =  cerebrospinal fluid; V.L.  =  viral load; RRMS relapsing-remitting multiple sclerosis; OIND  =  other inflammatory neurological diseases; NIND  =  non-inflammatory neurological diseases or normal findings; OR  =  odd ratio.</p><p>*Median refers to positive samples.</p
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