267 research outputs found

    Gliding on Ice in search of accurate and cost-effective computational methods for Astrochemistry on Grains: the puzzling case of the HCN isomerization

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    The isomerization of hydrogen cyanide to hydrogen isocyanide on icy grain surfaces is investigated by an accurate composite method (jun-Cheap) rooted in the coupled cluster ansatz and by density functional approaches. After benchmarking density functional predictions of both geometries and reaction energies against jun-Cheap results for the relatively small model system HCN···(H2O)2, the best performing DFT methods are selected. A large cluster containing 20 water molecules is then employed within a QM/QM′ approach to include a realistic environment mimicking the surface of icy grains. Our results indicate that four water molecules are directly involved in a proton relay mechanism, which strongly reduces the activation energy with respect to the direct hydrogen transfer occurring in the isolated molecule. Further extension of the size of the cluster up to 192 water molecules in the framework of a three-layer QM/QM′/MM model has a negligible effect on the energy barrier ruling the isomerization. Computation of reaction rates by the transition state theory indicates that on icy surfaces, the isomerization of HNC to HCN could occur quite easily even at low temperatures thanks to the reduced activation energy that can be effectively overcome by tunneling

    Empathy through the Pandemic: Changes of Different Emphatic Dimensions during the COVID-19 Outbreak

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    Growing evidence suggests that empathy is a relevant psychological trait to face the challenges imposed by the COVID-19 pandemic, but at the present very little is known on whether this multi-dimensional construct has been affected by the pandemic outbreak differently in its separate components. Here, we aimed at filling this gap by capitalizing on the opportunity of having collected data from different self-report measures and cognitive tasks assessing the main dimensions of empathy immediately before the beginning of the global pandemic and about one year later. The results showed a detrimental impact of the pandemic outbreak on empathic social skills but not on both cognitive (perspective-taking) and emotional empathy that instead significantly improved. Thus, reduced empathic social skills could be a weakness to be targeted in psychological interventions to help people cope with the mental health challenges related to COVID-19 pandemic, whereas the ability of understanding another’s mental states and emotions could represent a strength in dealing with the current long-lasting crisis

    Fecal Calprotectin Predicts Mucosal Healing in Patients With Ulcerative Colitis Treated With Biological Therapies: A Prospective Study

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    INTRODUCTION: Biological therapies are widely used for the treatment of ulcerative colitis. However, only a low proportion of patients achieve clinical remission and even less mucosal healing. There is currently scarce knowledge about the early markers of therapeutic response, with particular regard to mucosal healing. The aim of this prospective study was to evaluate the role of fecal calprotectin (FC) as early predictor of mucosal healing. METHODS: A prospective observational study was conducted on patients with ulcerative colitis, who started biological therapy with infliximab, adalimumab, golimumab, or vedolizumab at our center. All patients underwent colonoscopy, performed by 2 blinded operators, at baseline and week 54 or in case of therapy discontinuation because of loss of response. FC was assessed at baseline and week 8 and evaluated as putative predictor of mucosal healing at week 54. RESULTS: We enrolled 109 patients, and 97 were included in the analysis. Twenty-six patients (27%) experienced loss of response. Over 71 patients (73%) with clinical response at week 54, clinical remission was obtained in 60 patients (61.9%) and mucosal healing in 45 patients (46.4%). After 8 weeks of treatment, FC predicted mucosal healing at week 54 (P < 0.0001). Sensitivity, specificity, positive predictive value, and negative predictive value were estimated to be 75%, 88.9%, 86.6%, and 75.5%, respectively, based on a cutoff of 157.5 mg/kg. DISCUSSION: The present study suggests that FC assessment after 8 weeks of treatment with all the biological drugs could represent a promising early marker of response to therapy in terms of mucosal healing

    Risk and resilience factors for specific and general psychopathology worsening in people with Eating Disorders during COVID-19 pandemic: a retrospective Italian multicentre study

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    Purpose: The COVID-19 pandemic restrictions had negative impact on the psychopathology of people with Eating Disorders (EDs). Factors involved in the vulnerability to stressful events have been under-investigated in this population. We aimed to assess which factors contributed to COVID-19-induced worsening in both general and specific psychopathology. Methods: Three-hundred and twelve people with a clinically defined diagnosis of an ED and undergoing a specialist ED treatment in different Italian ED services before the spreading of COVID-19 pandemic filled in an online survey. ED specific and general psychopathology changes after COVID-19 quarantine were retrospectively evaluated. Factors related to COVID-19 concerns (financial condition, fear of contagion, perceived social isolation/support, satisfaction in peer, family or sentimental relationships), illness duration and treatment-related variables (type of treatment provided, type of access to care, satisfaction with therapeutic relationships) were included as predicting factors in a structural equational model, which included latent variables consisting of general and ED psychopathology items as outcomes. Results: A perceived low quality of therapeutic relationships, fear of contagion and increased isolation were positively associated with psychopathology worsening. Reduced satisfaction with family and with friends’ relationships and reduced perceived social support were associated with ED and general symptoms deterioration, respectively. No significant effect emerged for intimate relationships, illness duration, economic condition and type of treatment. Conclusions: This study provides a comprehensive evaluation of clinical variables associated with psychopathological changes during the COVID-19 lockdown period highlighting potential risk and resilience factors and, possibly, informing treatment as well as prevention strategies for EDs. Level of evidence IV: Evidence obtained from multiple time series analysis such as case studies

    Risk and resilience factors for specific and general psychopathology worsening in people with Eating Disorders during COVID-19 pandemic: a retrospective Italian multicentre study

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    Purpose: The COVID-19 pandemic restrictions had negative impact on the psychopathology of people with Eating Disorders (EDs). Factors involved in the vulnerability to stressful events have been under-investigated in this population. We aimed to assess which factors contributed to COVID-19-induced worsening in both general and specific psychopathology. Methods: Three-hundred and twelve people with a clinically defined diagnosis of an ED and undergoing a specialist ED treatment in different Italian ED services before the spreading of COVID-19 pandemic filled in an online survey. ED specific and general psychopathology changes after COVID-19 quarantine were retrospectively evaluated. Factors related to COVID-19 concerns (financial condition, fear of contagion, perceived social isolation/support, satisfaction in peer, family or sentimental relationships), illness duration and treatment-related variables (type of treatment provided, type of access to care, satisfaction with therapeutic relationships) were included as predicting factors in a structural equational model, which included latent variables consisting of general and ED psychopathology items as outcomes. Results: A perceived low quality of therapeutic relationships, fear of contagion and increased isolation were positively associated with psychopathology worsening. Reduced satisfaction with family and with friends\u2019 relationships and reduced perceived social support were associated with ED and general symptoms deterioration, respectively. No significant effect emerged for intimate relationships, illness duration, economic condition and type of treatment. Conclusions: This study provides a comprehensive evaluation of clinical variables associated with psychopathological changes during the COVID-19 lockdown period highlighting potential risk and resilience factors and, possibly, informing treatment as well as\ua0prevention strategies for EDs. Level of evidence IV: Evidence obtained from multiple time series analysis such as case studies

    Complexity and dynamics of the winemaking bacterial communities in berries, musts, and wines from apulian grape cultivars through time and space

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    Currently, there is very little information available regarding the microbiome associated with the wine production chain. Here, we used an amplicon sequencing approach based on high-throughput sequencing (HTS) to obtain a comprehensive assessment of the bacterial community associated with the production of three Apulian red wines, from grape to final product. The relationships among grape variety, the microbial community, and fermentation was investigated. Moreover, the winery microbiota was evaluated compared to the autochthonous species in vineyards that persist until the end of the winemaking process. The analysis highlighted the remarkable dynamics within the microbial communities during fermentation. A common microbial core shared among the examined wine varieties was observed, and the unique taxonomic signature of each wine appellation was revealed. New species belonging to the genus Halomonas were also reported. This study demonstrates the potential of this metagenomic approach, supported by optimized protocols, for identifying the biodiversity of the wine supply chain. The developed experimental pipeline offers new prospects for other research fields in which a comprehensive view of microbial community complexity and dynamics is desirable.Peer ReviewedPostprint (published version

    Regionally Specific White Matter Disruptions of Fornix and Cingulum in Schizophrenia

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    Limbic circuitry disruptions have been implicated in the psychopathology and cognitive deficits of schizophrenia, which may involve white matter disruptions of the major tracts of the limbic system, including the fornix and the cingulum. Our study aimed to investigate regionally specific abnormalities of the fornix and cingulum in schizophrenia using diffusion tensor imaging (DTI). We determined the fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) profiles along the fornix and cingulum tracts using a fibertracking technique and a brain mapping algorithm, the large deformation diffeomorphic metric mapping (LDDMM), in the DTI scans of 33 patients with schizophrenia and 31 age-, gender-, and handedness-matched healthy controls. We found that patients with schizophrenia showed reduction in FA and increase in RD in bilateral fornix, and increase in RD in left anterior cingulum when compared to healthy controls. In addition, tract-based analysis revealed specific loci of these white matter differences in schizophrenia, that is, FA reductions and AD and RD increases occur in the region of the left fornix further from the hippocampus, FA reductions and RD increases occur in the rostral portion of the left anterior cingulum, and RD and AD increases occur in the anterior segment of the left middle cingulum. In patients with schizophrenia, decreased FA in the specific loci of the left fornix and increased AD in the right cingulum adjoining the hippocampus correlated with greater severity of psychotic symptoms. These findings support precise disruptions of limbic-cortical integrity in schizophrenia and disruption of these structural networks may contribute towards the neural basis underlying the syndrome of schizophrenia and clinical symptomatology

    Streptococcus iniae M-Like Protein Contributes to Virulence in Fish and Is a Target for Live Attenuated Vaccine Development

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    Streptococcus iniae is a significant pathogen in finfish aquaculture, though knowledge of virulence determinants is lacking. Through pyrosequencing of the S. iniae genome we have identified two gene homologues to classical surface-anchored streptococcal virulence factors: M-like protein (simA) and C5a peptidase (scpI).S. iniae possesses a Mga-like locus containing simA and a divergently transcribed putative mga-like regulatory gene, mgx. In contrast to the Mga locus of group A Streptococcus (GAS, S. pyogenes), scpI is located distally in the chromosome. Comparative sequence analysis of the Mgx locus revealed only one significant variant, a strain with an insertion frameshift mutation in simA and a deletion mutation in a region downstream of mgx, generating an ORF which may encode a second putative mga-like gene, mgx2. Allelic exchange mutagenesis of simA and scpI was employed to investigate the potential role of these genes in S. iniae virulence. Our hybrid striped bass (HSB) and zebrafish models of infection revealed that M-like protein contributes significantly to S. iniae pathogenesis whereas C5a peptidase-like protein does not. Further, in vitro cell-based analyses indicate that SiMA, like other M family proteins, contributes to cellular adherence and invasion and provides resistance to phagocytic killing. Attenuation in our virulence models was also observed in the S. iniae isolate possessing a natural simA mutation. Vaccination of HSB with the Delta simA mutant provided 100% protection against subsequent challenge with a lethal dose of wild-type (WT) S. iniae after 1,400 degree days, and shows promise as a target for live attenuated vaccine development.Analysis of M-like protein and C5a peptidase through allelic replacement revealed that M-like protein plays a significant role in S. iniae virulence, and the Mga-like locus, which may regulate expression of this gene, has an unusual arrangement. The M-like protein mutant created in this research holds promise as live-attenuated vaccine
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