463 research outputs found

    Borders, Common Currencies, Trade, and Welfare: What Can We Learn from the Evidence?

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    Recent evidence indicates that the intensity of economic exchange within and across borders is significantly different: linkages are much tighter within, than among, nation-states. These findings, however, do not necessarily imply that borders and separate national currencies represent significant barriers to trade that should be removed, since the evidence is also consistent with the alternative hypothesis, that domestic exchange is more efficient because domestic producers are better able to satisfy the requirements of local consumers, owing to common tastes and institutions and the existence of local information and social networks. Focusing primarily on trade linkages within and between Canada and the United States, the authors review the evidence on the extent to which national borders lessen the intensity of international economic linkages, primarily trade in goods and services, and the effects on domestic welfare. They also examine the evidence on the impact of common currencies on trade and welfare. They determine that, since the empirical models employed to date in this research cannot distinguish between alternative explanations of the evidence, it is not yet possible to draw firm conclusions for policy-making.

    Report on a survey of the terrestrial ecological resources of the Qawra/Dwejra area, Western Gozo, commissioned by Nature Trust (Malta)

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    The present survey of the terrestrial ecological resources of the Qawra/Dwejra area, Western Gozo has been commissioned by Nature Trust (Malta). The report describes the late dry-season terrestrial environment within an area that follows the boundaries of the proposed Qawra/Dwejra Heritage Park and evaluates the ecological and conservation significance of the biotic assemblages present within this area. The present study is being carried out in the context of the Dwejra LIFE project, awarded to Nature Trust (Malta) under the LIFE-Third Countries component of the European Union’s LIFE programme (Commission Reference: LIFE03 TCY/MT/000047). The Project was awarded to Nature Trust (Malta) in 2003 and runs from 1st April 2004 to 31st March 2007. Project partners include the Malta Environment and Planning Authority and Associazione Italiana per il WWF. The general aims of the project are as follows: Development of a restoration / conservation and management plan. Establishment of a framework for environmental management. Strengthening of current administrative and enforcement capacities. Implementation of environmental education programmes through the creation of an eco-tourism and environmental education site. Use of the project as a demonstration for the creation of further coastal nature reserves. Creation of a Coastal Nature Reserve which conforms with the objectives of the Coastal Zone Management Subject Plan, as well as the Structure Plan for Malta and Gozo.peer-reviewe

    The mutual relationship between heart failure and atrial fibrillation

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    Atrial fibrillation (AF) and Heart Failure (HF) are evolving epidemies, together responsible for substantial human suffering and health-care expenditure. The simultaneous co-existence of the two conditions is associated with higher mortality rates than those observed in individuals with only one or none of them. Patients with concomitant HF and AF suffer from even worse symptoms and poorer prognosis, yet evidence-based evaluation and management of this group of patients is lacking. In this review, we evaluate the common mechanisms for the development of AF in HF patients and vice versa, focusing on the evidence for potential treatment strategies. Recent data have suggested that these patients may respond differently if compared to those with HF or AF alone. These results highlight the clear clinical need to identify and treat these diseases according to best evidence, in order to prevent adverse outcomes and reduce the huge burden er that HF and AF are expected to have on global healthcare systems in the future

    Psychological impact of lung cancer screening using a novel antibody blood test followed by imaging : the ECLS randomized controlled trial

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    This work was supported by the Scottish Government and Oncimmune Ltd. Follow-up data collection for psychological outcome measures was supported by Oncimmune Ltd.Background: The Early CDT®-Lung antibody blood test plus serial computed tomography scans for test-positives (TPGs) reduces late-stage lung cancer presentation. This study assessed the psychological outcomes of this approach. Methods: Randomized controlled trial (n = 12 208) comparing psychological outcomes 1-12 months post-recruitment in a subsample (n = 1032) of TPG, test-negative (TNG) and control groups (CG). Results: Compared to TNG, TPG had lower positive affect (difference between means (DBM), 3 months (3m: -1.49 (-2.65, - 0.33)), greater impact of worries (DBM 1m: 0.26 (0.05, 0.47); 3m: 0.28 (0.07, 0.50)), screening distress (DBM 1m: 3.59 (2.28, 4.90); 3m: 2.29 (0.97, 3.61); 6m: 1.94 (0.61, 3.27)), worry about tests (odds ratio (OR) 1m: 5.79 (2.66, 12.63) and more frequent lung cancer worry (OR 1m: 2.52 (1.31, 4.83); 3m: 2.43 (1.26, 4.68); 6m: 2.87 (1.48, 5.60)). Compared to CG, TPG had greater worry about tests (OR 1m: 3.40 (1.69, 6.84)). TNG had lower negative affect (log-transformed DBM 3m: -0.08 (-0.13, -0.02)), higher positive affect (DBM 1m: 1.52 (0.43, 2.61); 3m: 1.43 (0.33, 2.53); 6m: 1.27 (0.17, 2.37)), less impact of worries (DBM 3m: -0.27 (-0.48, -0.07)) and less-frequent lung cancer worry (OR 3m: 0.49 (0.26, 0.92)). Conclusions: Negative psychological effects in TPG and positive effects in TNG were short-lived and most differences were small.Publisher PDFPeer reviewe

    Lineage-Specific Methyltransferases Define the Methylome of the Globally Disseminated Escherichia coli ST131 Clone.

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    UNLABELLED: Escherichia coli sequence type 131 (ST131) is a clone of uropathogenic E. coli that has emerged rapidly and disseminated globally in both clinical and community settings. Members of the ST131 lineage from across the globe have been comprehensively characterized in terms of antibiotic resistance, virulence potential, and pathogenicity, but to date nothing is known about the methylome of these important human pathogens. Here we used single-molecule real-time (SMRT) PacBio sequencing to determine the methylome of E. coli EC958, the most-well-characterized completely sequenced ST131 strain. Our analysis of 52,081 methylated adenines in the genome of EC958 discovered three (m6)A methylation motifs that have not been described previously. Subsequent SMRT sequencing of isogenic knockout mutants identified the two type I methyltransferases (MTases) and one type IIG MTase responsible for (m6)A methylation of novel recognition sites. Although both type I sites were rare, the type IIG sites accounted for more than 12% of all methylated adenines in EC958. Analysis of the distribution of MTase genes across 95 ST131 genomes revealed their prevalence is highly conserved within the ST131 lineage, with most variation due to the presence or absence of mobile genetic elements on which individual MTase genes are located. IMPORTANCE: DNA modification plays a crucial role in bacterial regulation. Despite several examples demonstrating the role of methyltransferase (MTase) enzymes in bacterial virulence, investigation of this phenomenon on a whole-genome scale has remained elusive until now. Here we used single-molecule real-time (SMRT) sequencing to determine the first complete methylome of a strain from the multidrug-resistant E. coli sequence type 131 (ST131) lineage. By interrogating the methylome computationally and with further SMRT sequencing of isogenic mutants representing previously uncharacterized MTase genes, we defined the target sequences of three novel ST131-specific MTases and determined the genomic distribution of all MTase target sequences. Using a large collection of 95 previously sequenced ST131 genomes, we identified mobile genetic elements as a major factor driving diversity in DNA methylation patterns. Overall, our analysis highlights the potential for DNA methylation to dramatically influence gene regulation at the transcriptional level within a well-defined E. coli clone

    Multiple evolutionary trajectories for non-O157 Shiga toxigenic Escherichia coli

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    AbstractBackgroundShiga toxigenic Escherichia coli (STEC) is an emerging global pathogen and remains a major cause of food-borne illness with more severe symptoms including hemorrhagic colitis and hemolytic-uremic syndrome. Since the characterization of the archetypal STEC serotype, E. coli O157:H7, more than 250 STEC serotypes have been defined. Many of these non-O157 STEC are associated with clinical cases of equal severity as O157. In this study, we utilize whole genome sequencing of 44 STEC strains from eight serogroups associated with human infection to establish their evolutionary relationships and contrast this with their virulence gene profiles and established typing methods.ResultsOur phylogenomic analysis delineated these STEC strains into seven distinct lineages, each with a characteristic repertoire of virulence factors. Some lineages included commensal or other E. coli pathotypes. Multiple independent acquisitions of the Locus for Enterocyte Effacement were identified, each associated with a distinct repertoire of effector genes. Lineages were inconsistent with O-antigen typing in several instances, consistent with lateral gene transfer within the O-antigen locus. STEC lineages could be defined by the conservation of clustered regularly interspaced short palindromic repeats (CRISPRs), however, no CRISPR profile could differentiate STEC from other E. coli strains. Six genomic regions (ranging from 500 bp - 10 kbp) were found to be conserved across all STEC in this dataset and may dictate interactions with Stx phage lysogeny.ConclusionsThe genomic analyses reported here present non-O157 STEC as a diverse group of pathogenic E. coli emerging from multiple lineages that independently acquired mobile genetic elements that promote pathogenesis.</jats:sec

    Nine-year nationwide environmental surveillance of hepatitis E virus in urban wastewaters in Italy (2011–2019)

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    Hepatitis E virus (HEV) is an emerging causative agent of acute hepatitis worldwide. To provide insights into the epidemiology of HEV in Italy, a large-scale investigation was conducted into urban sewage over nine years (2011–2019), collecting 1374 sewage samples from 48 wastewater treatment plants located in all the 20 regions of Italy. Broadly reactive primers targeting the ORF1 and ORF2 regions were used for the detection and typing of HEV, followed by Sanger and next generation sequencing (NGS). Real-time RT-qPCR was also used to attempt quantification of positive samples. HEV RNA detection occurred in 74 urban sewage samples (5.4%), with a statistically significant higher frequency (7.1%) in central Italy. Fifty-six samples were characterized as G3 strains and 18 as G1. While the detection of G3 strains occurred in all the surveillance period, G1 strains were mainly detected in 2011–2012, and never in 2017–2019. Typing was achieved in 2 samples (3f subtype). Viral concentrations in quantifiable samples ranged from 1.2 × 103 g.c./L to 2.8 × 104 g.c./L. Our results suggest the considerable circulation of the virus in the Italian population, despite a relatively small number of notified cases, a higher occurrence in central Italy, and a noteworthy predominance of G3 strains

    A novel method of serum resistance by Escherichia coli that causes urosepsis

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    Uropathogenic Escherichia coli (UPEC) is the most common cause of urinary tract infection, which in some patients can develop into life-threatening urosepsis. Serum resistance is a key virulence trait of strains that cause urosepsis. Recently, we identified a novel method of serum resistance in patients with Pseudomonas aeruginosa lung infections, where patients possessed antibodies that inhibited complement-mediated killing (instead of protecting against infection). These inhibitory antibodies were of the IgG2 subtype, specific to the O-antigen component of lipopolysaccharide (LPS) and coated the bacterial surface, preventing bacterial lysis by complement. As this mechanism could apply to any Gram-negative bacterial infection, we hypothesized that inhibitory antibodies may represent an uncharacterized mechanism of serum resistance in UPEC. To test this, 45 urosepsis patients with paired blood culture UPEC isolates were screened for serum titers of IgG2 specific for their cognate strain’s LPS. Eleven patients had sufficiently high titers of the antibody to inhibit serum-mediated killing of UPEC isolates by pooled healthy control sera. Depletion of IgG or removal of O-antigen restored sensitivity of the isolates to the cognate patient serum. Importantly, the isolates from these 11 patients were more sensitive to killing by serum than isolates from patients with no inhibitory antibodies. This suggests the presence of inhibitory antibodies may have allowed these strains to infect the bloodstream. The high prevalence of patients with inhibitory antibodies (24%) suggests that this phenomenon is an important mechanism of UPEC serum resistance. LPS-specific inhibitory antibodies have now been identified against three Gram-negative pathogens that cause disparate diseases.Despite improvements in the early detection and management of sepsis, morbidity and mortality are still high. Infections of the urinary tract are one of the most frequent sources of sepsis with Escherichia coli the main causative agent. Serum resistance is vital for bacteria to infect the bloodstream. Here we report a novel method of serum resistance found in patients with UPEC-mediated sepsis. Antibodies in sera usually protect against infection, but here we found that 24% of patients expressed “inhibitory antibodies” capable of preventing serum-mediated killing of their infecting isolate. Our data suggest that these antibodies would allow otherwise serum-sensitive UPEC strains to cause sepsis. The high prevalence of patients with inhibitory antibodies in this cohort suggests that this is a widespread mechanism of resistance to complement-mediated killing in urosepsis patients, invoking the potential for the application of new methods to prevent and treat sepsis

    Electron/pion separation with an Emulsion Cloud Chamber by using a Neural Network

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    We have studied the performance of a new algorithm for electron/pion separation in an Emulsion Cloud Chamber (ECC) made of lead and nuclear emulsion films. The software for separation consists of two parts: a shower reconstruction algorithm and a Neural Network that assigns to each reconstructed shower the probability to be an electron or a pion. The performance has been studied for the ECC of the OPERA experiment [1]. The e/Ď€e/\pi separation algorithm has been optimized by using a detailed Monte Carlo simulation of the ECC and tested on real data taken at CERN (pion beams) and at DESY (electron beams). The algorithm allows to achieve a 90% electron identification efficiency with a pion misidentification smaller than 1% for energies higher than 2 GeV
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