650 research outputs found

    A novel bacterial l-arginine sensor controlling c-di-GMP levels in Pseudomonas aeruginosa

    Get PDF
    Nutrients such as amino acids play key roles in shaping the metabolism of microorganisms in natural environments and in host–pathogen interactions. Beyond taking part to cellular metabolism and to protein synthesis, amino acids are also signaling molecules able to influence group behavior in microorganisms, such as biofilm formation. This lifestyle switch involves complex metabolic reprogramming controlled by local variation of the second messenger 3′, 5′-cyclic diguanylic acid (c-di-GMP). The intracellular levels of this dinucleotide are finely tuned by the opposite activity of dedicated diguanylate cyclases (GGDEF signature) and phosphodiesterases (EAL and HD-GYP signatures), which are usually allosterically controlled by a plethora of environmental and metabolic clues. Among the genes putatively involved in controlling c-di-GMP levels in P. aeruginosa, we found that the multidomain transmembrane protein PA0575, bearing the tandem signature GGDEF-EAL, is an l-arginine sensor able to hydrolyse c-di-GMP. Here, we investigate the basis of arginine recognition by integrating bioinformatics, molecular biophysics and microbiology. Although the role of nutrients such as l-arginine in controlling the cellular fate in P. aeruginosa (including biofilm, pathogenicity and virulence) is already well established, we identified the first l-arginine sensor able to link environment sensing, c-di-GMP signaling and biofilm formation in this bacterium

    Blood and sputum biomarkers in COPD and asthma: a review

    Get PDF
    Chronic obstructive pulmonary disease (COPD) and asthma are lung inflammatory diseases that represent major public health problems. The primary, and often unique, method to evaluate lung function is spirometry, which reflects disease severity rather than disease activity. Moreover, its measurements strictly depend on patient's compliance, physician's expertise and data interpretation. The limitations of clinical history and pulmonary function tests have encouraged focusing on new possible tracers of diseases. The increase of the inflammatory response in the lungs represents an early pathological event, so biological markers related to inflammation may play key roles in earlier diagnosis, evaluation of functional impairment and prognosis. Biomarkers are measurable indicators associated with the presence and/or severity of a biological or pathogenic process, which may predict functional impairment, prognosis and response to therapy. The traditional approach based on invasive techniques (bronchoalveolar lavage and biopsies) may be replaced, at least in part, by using less invasive methods to collect specimens (sputum and blood), in which biomarkers could be measured. Proteomics, by the association between different protein profiles and pathogenic processes, is gaining an important role in pulmonary medicine allowing a more precise discrimination between patients with different outcomes and response to therapy. The aim of this review was to evaluate the use of biomarkers of airway inflammation in the context of both research and clinical practice

    the combination of a smoking cessation programme with rehabilitation increases stop smoking rate

    Get PDF
    Objective and study design: A parallel group study to investigate the effectiveness of a smoking cessation programme performed during routine rehabilitation practice for outpatients. Patients and methods: The study participants comprised an intervention group of 102 consecutive smokers who underwent a smoking cessation programme in a rehabilitation centre and a control group of 101 consecutive smokers who were referred to a smoking cessation centre in a pulmonary hospital. All participants underwent physical examination, pulmonary function tests and received identical behavioural and/or pharmacological treatment. In addition, the intervention group underwent rehabilitation practice 3 times a week for 3 months. Results: The continuous abstinence rate at 12 months, which was validated by an expired air carbon monoxide concentration of 10 parts per million or less and a household interview, was 68% in the intervention group and 32% in the control group. Multivariable analysis showed that rehabilitation was significantly associated with smoking cessation after ad justing for years of smoking, number of cigarettes smoked, gender and treatment (odds ratio = 4.34, p < 0.001). Conclusion: This study suggests that smoking cessation programmes during routine rehabilitation may be highly effective in helping smoking withdrawal and should be a strongly recommended component of rehabilitation practice

    Alexithymia and obesity: controversial findings from a multimethod assessment

    Get PDF
    OBJECTIVE: The aim of the study is to assess alexithymia levels in obese patients using a multimethod measurement (TAS-20 and TSIA) to evaluate both possible differences between the two instruments and their relationship with body weight. PATIENTS AND METHODS: 54 obese patients, seeking surgical treatment, were enrolled. They completed a socio-demographic questionnaire, 20-items Toronto Alexithymia Scale and the Toronto Structured Interview for Alexithymia. RESULTS: Data analysis showed a significant positive association between TAS-20 and TSIA total scores (r=.28, p&lt;.05), but only the TSIA score was positively related to body weight (r=.39; p&lt;.001). Multivariable linear regression models showed the predictive effects of TSIA total score (beta=.41; p&lt;.001) and difficulty in identifying feelings (DIF) (beta=.56; p&lt;.001) respectively on weight. CONCLUSIONS: The findings showed a different association between body weight and alexithymia according to the instrument employed to evaluate alexithymia, supporting the importance of a multimethod assessment in some clinical conditions

    Creating and Managing Dynamic Cloud Federations

    Get PDF
    Cloud computing has evolved from a promising approach to the service provisioning to the reference model for all new data centres to build. Additionally, an increasing number of companies are choosing to migrate their business in the cloud "ecosystem" adopting the solutions developed by the biggest public Cloud Service Providers (CSPs). Smaller CSPs build their infrastructure on technologies available and to better support user activities and provide enough resources to their users, the federation could be a possible solution. In this work, we present different federation models, showing their strengths and weakness together with our considerations. Beside the highlighted existing federation we show the design of a new implementations under development at INFN aiming at maximising the scalability and flexibility of small and/or hybrid clouds by the introduction of a federation manager. This new component will support a seamless resources renting on the base of acceptance of federation agreements among operators. Additionally, we will discuss how the implementation of this model inside research institutes could help in the field of High Energy Physics with explicit reference at LHC experiments, digital humanities, life sciences and others

    A first attempt to evaluate the toxicity to Phaeodactylum tricornutum Bohlin exposed to rare earth elements

    Get PDF
    The increasing use and demand of rare earth elements in many emerging technologies is leading to a potentially higher input to the marine environment. This study compared for the first time the effect of lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), dysprosium (Dy), and erbium (Er) to the microalga Phaeodactylum tricornutum Bohlin. The algal growth inhibition was investigated after 72 h of exposure. The median effect concentrations (EC50) ranged from 0.98 mg/L to 13.21 mg/L and elements were ranked as follows: Gd > Ce > Er > La > Eu > Nd > Dy > Sm. The comparison of predicted no effect concentrations (PNEC) for hazard and risk assessment with measured environmental concentrations showed that ecological risks deriving from REEs could be present, but limited to specific environments like estuarine waters. The results support evidence of actions to manage the REE impact in seawater environments, looking to improve the monitoring tailored to the different and dynamic nature of ecosystems
    • …
    corecore