331 research outputs found

    Current treatment goals are achieved by the majority of patients with atopic dermatitis treated with tralokinumab: results from a multicentric, multinational, retrospective, cohort study

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    Background: Tralokinumab is a human monoclonal antibody targeting interleukin-13 that is approved for the treatment of moderate-severe atopic dermatitis. Studies analyzing the efficacy and safety of tralokinumab in a real-world setting are scarce. Research design and methods: A European, multicentric, real-world, retrospective cohort study was defined to assess the effectiveness and safeness profile of tralokinumab, investigating the achievement of pre-specified treatment goals; and to detect potential differences in terms of effectiveness and safeness across some selected patient subcohorts. Results: A total of 194 adult patients were included in this study. A significant improvement in physician-assessed disease severity was detected at each follow-up visit as compared with baseline and similar trend was observed for patient-reported outcomes and quality of life. No meaningful difference in effectiveness was found when considering patient age (<65 versus ≥65 years), neither dissecting patient cohort in dupilumab-naive vs dupilumab-treated subjects. Among tralokinumabtreated patients, 88% achieved at least one currently identified real-world therapeutic goal at week 16. Conclusions: This retrospective multicenter study confirmed the effectiveness and safeness of tralokinumab throughout 32 weeks of observation, showing the achievement of therapeutic goals identified in both trial and real-world settings in a large proportion of tralokinumab-treated patients

    Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up

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    Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated

    Genetic plasticity of the Shigella virulence plasmid is mediated by intra- and inter-molecular events between insertion sequences

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    Acquisition of a single copy, large virulence plasmid, pINV, led to the emergence of Shigella spp. from Escherichia coli. The plasmid encodes a Type III secretion system (T3SS) on a 30kb pathogenicity island (PAI), and is maintained in a bacterial population through a series of toxin:antitoxin (TA) systems which mediate post-segrega tional killing (PSK). The T3SS imposes a significant cost on the bacterium, and strains which have lost the plasmid and/or genes encoding the T3SS grow faster than wild-type strains in the laboratory, and fail to bind the indicator dye Congo Red (CR). Our aim was to define the molecular events in Shigella flexneri that cause loss of Type III secretion (T3S), and to examine whether TA systems exert positional effects on pINV. During growth at 37°C, we found that deletions of regions of the plasmid including the PAI lead to the emergence of CR-negative colonies; deletions occur through intra-molecula r recombination events between insertion sequences (ISs) flanking the PAI. Furthermore, by repositioning MvpAT (which belongs to the VapBC family of TA systems) near the PAI, we demonstrate that the location of this TA system alters the rearrangements that lead to loss of T3S, indicating that MvpAT acts both globally (by reducing loss of pINV through PSK) as well as locally (by preventing loss of adjacent sequences). During growth at environmental temperatures, we show for the first time that pINV spontaneously integrates into different sites in the chromosome, and this is mediated by inter-molecular events involving IS 1294. Integration leads to reduced PAI gene expression and impaired secretion through the T3SS, while excision of pINV from the chromosome restores T3SS function. Therefore, pINV integration provides a reversible mechanism for Shigella to circumvent the metabolic burden imposed by pINV. Intra- and inter-molecular events between ISs, which are abundant in Shigella spp., mediate plasticity of S. flexneri pINV

    Properties of an alkali-thermo stable xylanase from Geobacillus thermodenitrificans A333 and applicability in xylooligosaccharides generation

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    An extracellular thermo-alkali-stable and cellulase-free xylanase from Geobacillus thermodenitrificans A333 was purified to homogeneity by ion exchange and size exclusion chromatography. Its molecular mass was 44 kDa as estimated in native and denaturing conditions by gel filtration and SDS-PAGE analysis, respectively. The xylanase (GtXyn) exhibited maximum activity at 70 °C and pH 7.5. It was stable over broad ranges of temperature and pH retaining 88 % of activity at 60 °C and up to 97 % in the pH range 7.5–10.0 after 24 h. Moreover, the enzyme was active up to 3.0 M sodium chloride concentration, exhibiting at that value 70 % residual activity after 1 h. The presence of other metal ions did not affect the activity with the sole exceptions of K+ that showed a stimulating effect, and Fe2+, Co2+ and Hg2+, which inhibited the enzyme. The xylanase was activated by non-ionic surfactants and was stable in organic solvents remaining fully active over 24 h of incubation in 40 % ethanol at 25 °C. Furthermore, the enzyme was resistant to most of the neutral and alkaline proteases tested. The enzyme was active only on xylan, showing no marked preference towards xylans from different origins. The hydrolysis of beechwood xylan and agriculture-based biomass materials yielded xylooligosaccharides with a polymerization degree ranging from 2 to 6 units and xylobiose and xylotriose as main products. These properties indicate G. thermodenitrificans A333 xylanase as a promising candidate for several biotechnological applications, such as xylooligosaccharides preparation

    Differential Gene Repertoire in Mycobacterium ulcerans Identifies Candidate Genes for Patho-Adaptation

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    The emerging human disease Buruli ulcer, caused by Mycobacterium ulcerans, is of increasing challenge for public health systems in many countries, mainly in West and Central sub-Saharan Africa. Genetic differentiation of patient isolates, a prerequisite for scientific studies on and intervention of disease transmission and dispersal, is hampered by an exceptional lack of genetic diversity within this species. Comparative genomics on M. ulcerans of worldwide geographical origin has already allowed for distinguishing several haplotypes separated into two distinct lineages. Differences in prevalence and incidence of Buruli ulcer were already suspected, but biological relevance for this was unclear. Here, we show newly identified hot spot regions of genomic instability, a biased silencing of coding sequences belonging to distinct functional groups, and a differential gene repertoire across M. ulcerans strains. Gene inactivation mediated by different mechanisms in M. ulcerans adds to the concept of anti-virulence genes observed in an increasing number of bacterial species. According to this concept, loss of such genes—in addition to gain of function—may confer a selective advantage for a pathogen radiating into a new niche. In the case of M. ulcerans, a distinct set of disrupted genes may enhance virulence, particularly in the classical lineage

    Host-Pathogen O-Methyltransferase Similarity and Its Specific Presence in Highly Virulent Strains of Francisella tularensis Suggests Molecular Mimicry

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    Whole genome comparative studies of many bacterial pathogens have shown an overall high similarity of gene content (>95%) between phylogenetically distinct subspecies. In highly clonal species that share the bulk of their genomes subtle changes in gene content and small-scale polymorphisms, especially those that may alter gene expression and protein-protein interactions, are more likely to have a significant effect on the pathogen's biology. In order to better understand molecular attributes that may mediate the adaptation of virulence in infectious bacteria, a comparative study was done to further analyze the evolution of a gene encoding an o-methyltransferase that was previously identified as a candidate virulence factor due to its conservation specifically in highly pathogenic Francisella tularensis subsp. tularensis strains. The o-methyltransferase gene is located in the genomic neighborhood of a known pathogenicity island and predicted site of rearrangement. Distinct o-methyltransferase subtypes are present in different Francisella tularensis subspecies. Related protein families were identified in several host species as well as species of pathogenic bacteria that are otherwise very distant phylogenetically from Francisella, including species of Mycobacterium. A conserved sequence motif profile is present in the mammalian host and pathogen protein sequences, and sites of non-synonymous variation conserved in Francisella subspecies specific o-methyltransferases map proximally to the predicted active site of the orthologous human protein structure. Altogether, evidence suggests a role of the F. t. subsp. tularensis protein in a mechanism of molecular mimicry, similar perhaps to Legionella and Coxiella. These findings therefore provide insights into the evolution of niche-restriction and virulence in Francisella, and have broader implications regarding the molecular mechanisms that mediate host-pathogen relationships
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