458 research outputs found

    The O antigen is a critical antigen for the development of a protective immune response to Bordetella parapertussis

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    Despite excellent vaccine coverage in developed countries, whooping cough is a reemerging disease that can be caused by two closely related pathogens, Bordetella pertussis and B. parapertussis. The two are antigenically distinct, and current vaccines, containing only B. pertussis-derived antigens, confer efficient protection against B. pertussis but not against B. parapertussis. B. pertussis does not express the O antigen, while B. parapertussis retains it as a dominant surface antigen. Since the O antigen is a protective antigen for many pathogenic bacteria, we examined whether this factor is a potential protective antigen for B. parapertussis. In a mouse model of infection, immunization with wild-type B. parapertussis elicited a strong antibody response to the O antigen and conferred efficient protection against a subsequent B. parapertussis challenge. However, immunization with an isogenic mutant lacking the O antigen, B. parapertussis Δwbm, induced antibodies that recognized other antigens but did not efficiently mediate opsonophagocytosis of B. parapertussis. The passive transfer of sera raised against B. parapertussis, but not B. parapertussis Δwbm, reduced B. parapertussis loads in the lower respiratory tracts of mice. The addition of 10 μg of purified B. parapertussis lipopolysaccharide (LPS), which contains the O antigen, but not B. parapertussis Δwbm LPS drastically improved the efficacy of the acellular vaccine Adacel against B. parapertussis. These data suggest that the O antigen is a critical protective antigen of B. parapertussis and its inclusion can substantially improve whooping cough vaccine efficacy against this pathogen.Centro de Investigación y Desarrollo en Fermentaciones Industriale

    The O antigen is a critical antigen for the development of a protective immune response to<i> Bordetella parapertussis</i>

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    Despite excellent vaccine coverage in developed countries, whooping cough is a reemerging disease that can be caused by two closely related pathogens, Bordetella pertussis and B. parapertussis. The two are antigenically distinct, and current vaccines, containing only B. pertussis-derived antigens, confer efficient protection against B. pertussis but not against B. parapertussis. B. pertussis does not express the O antigen, while B. parapertussis retains it as a dominant surface antigen. Since the O antigen is a protective antigen for many pathogenic bacteria, we examined whether this factor is a potential protective antigen for B. parapertussis. In a mouse model of infection, immunization with wild-type B. parapertussis elicited a strong antibody response to the O antigen and conferred efficient protection against a subsequent B. parapertussis challenge. However, immunization with an isogenic mutant lacking the O antigen, B. parapertussis Δwbm, induced antibodies that recognized other antigens but did not efficiently mediate opsonophagocytosis of B. parapertussis. The passive transfer of sera raised against B. parapertussis, but not B. parapertussis Δwbm, reduced B. parapertussis loads in the lower respiratory tracts of mice. The addition of 10 μg of purified B. parapertussis lipopolysaccharide (LPS), which contains the O antigen, but not B. parapertussis Δwbm LPS drastically improved the efficacy of the acellular vaccine Adacel against B. parapertussis. These data suggest that the O antigen is a critical protective antigen of B. parapertussis and its inclusion can substantially improve whooping cough vaccine efficacy against this pathogen.Centro de Investigación y Desarrollo en Fermentaciones Industriale

    The O antigen is a critical antigen for the development of a protective immune response to Bordetella parapertussis

    Get PDF
    Despite excellent vaccine coverage in developed countries, whooping cough is a reemerging disease that can be caused by two closely related pathogens, Bordetella pertussis and B. parapertussis. The two are antigenically distinct, and current vaccines, containing only B. pertussis-derived antigens, confer efficient protection against B. pertussis but not against B. parapertussis. B. pertussis does not express the O antigen, while B. parapertussis retains it as a dominant surface antigen. Since the O antigen is a protective antigen for many pathogenic bacteria, we examined whether this factor is a potential protective antigen for B. parapertussis. In a mouse model of infection, immunization with wild-type B. parapertussis elicited a strong antibody response to the O antigen and conferred efficient protection against a subsequent B. parapertussis challenge. However, immunization with an isogenic mutant lacking the O antigen, B. parapertussis Δwbm, induced antibodies that recognized other antigens but did not efficiently mediate opsonophagocytosis of B. parapertussis. The passive transfer of sera raised against B. parapertussis, but not B. parapertussis Δwbm, reduced B. parapertussis loads in the lower respiratory tracts of mice. The addition of 10 μg of purified B. parapertussis lipopolysaccharide (LPS), which contains the O antigen, but not B. parapertussis Δwbm LPS drastically improved the efficacy of the acellular vaccine Adacel against B. parapertussis. These data suggest that the O antigen is a critical protective antigen of B. parapertussis and its inclusion can substantially improve whooping cough vaccine efficacy against this pathogen.Centro de Investigación y Desarrollo en Fermentaciones Industriale

    Financing Direct Democracy: Revisiting the Research on Campaign Spending and Citizen Initiatives

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    The conventional view in the direct democracy literature is that spending against a measure is more effective than spending in favor of a measure, but the empirical results underlying this conclusion have been questioned by recent research. We argue that the conventional finding is driven by the endogenous nature of campaign spending: initiative proponents spend more when their ballot measure is likely to fail. We address this endogeneity by using an instrumental variables approach to analyze a comprehensive dataset of ballot propositions in California from 1976 to 2004. We find that both support and opposition spending on citizen initiatives have strong, statistically significant, and countervailing effects. We confirm this finding by looking at time series data from early polling on a subset of these measures. Both analyses show that spending in favor of citizen initiatives substantially increases their chances of passage, just as opposition spending decreases this likelihood

    Activation in a Frontoparietal Cortical Network Underlies Individual Differences in the Performance of an Embedded Figures Task

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    The Embedded Figures Test (EFT) requires observers to search for a simple geometric shape hidden inside a more complex figure. Surprisingly, performance in the EFT is negatively correlated with susceptibility to illusions of spatial orientation, such as the Roelofs effect. Using fMRI, we previously demonstrated that regions in parietal cortex are involved in the contextual processing associated with the Roelofs task. In the present study, we found that similar parietal regions (superior parietal cortex and precuneus) were more active during the EFT than during a simple matching task. Importantly, these parietal activations overlapped with regions found to be involved during contextual processing in the Roelofs illusion. Additional parietal and frontal areas, in the right hemisphere, showed strong correlations between brain activity and behavioral performance during the search task. We propose that the posterior parietal regions are necessary for processing contextual information across many different, but related visuospatial tasks, with additional parietal and frontal regions serving to coordinate this processing in participants proficient in the task

    The Clinical Outcome Study for dysferlinopathy: An international multicenter study

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    Objective: To describe the baseline clinical and functional characteristics of an international cohort of 193 patients with dysferlinopathy. Methods: The Clinical Outcome Study for dysferlinopathy (COS) is an international multicenter study of this disease, evaluating patients with genetically confirmed dysferlinopathy over 3 years. We present a cross-sectional analysis of 193 patients derived from their baseline clinical and functional assessments. Results: There is a high degree of variability in disease onset, pattern of weakness, and rate of progression. No factor, such as mutation class, protein expression, or age at onset, accounted for this variability. Among patients with clinical diagnoses of Miyoshi myopathy or limb-girdle muscular dystrophy, clinical presentation and examination was not strikingly different. Respiratory impairment and cardiac dysfunction were observed in a minority of patients. A substantial delay in diagnosis was previously common but has been steadily reducing, suggesting increasing awareness of dysferlinopathies. Conclusions: These findings highlight crucial issues to be addressed for both optimizing clinical care and planning therapeutic trials in dysferlinopathy. This ongoing longitudinal study will provide an opportunity to further understand patterns and variability in disease progression and form the basis for trial design

    Convergence of marine megafauna movement patterns in coastal and open oceans

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    Author Posting. © The Author(s), 2017. This is the author's version of the work. It is posted here for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 115 (2018): 3072-3077, doi:10.1073/pnas.1716137115.The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals’ movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyse a global dataset of 2.8 million locations from > 2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared to more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal micro-habitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise and declining oxygen content.Workshops funding granted by the UWA Oceans Institute, AIMS, and KAUST. AMMS was supported by an ARC Grant DE170100841 and an IOMRC (UWA, AIMS, CSIRO) fellowship; JPR by MEDC (FPU program, Spain); DWS by UK NERC and Save Our Seas Foundation; NQ by FCT (Portugal); MMCM by a CAPES fellowship (Ministry of Education)

    Bordetella pertussis Infection or Vaccination Substantially Protects Mice against B. bronchiseptica Infection

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    Although B. bronchiseptica efficiently infects a wide range of mammalian hosts and efficiently spreads among them, it is rarely observed in humans. In contrast to the many other hosts of B. bronchiseptica, humans are host to the apparently specialized pathogen B. pertussis, the great majority having immunity due to vaccination, infection or both. Here we explore whether immunity to B. pertussis protects against B. bronchiseptica infection. In a murine model, either infection or vaccination with B. pertussis induced antibodies that recognized antigens of B. bronchiseptica and protected the lower respiratory tract of mice against three phylogenetically disparate strains of B. bronchiseptica that efficiently infect naïve animals. Furthermore, vaccination with purified B. pertussis-derived pertactin, filamentous hemagglutinin or the human acellular vaccine, Adacel, conferred similar protection against B. bronchiseptica challenge. These data indicate that individual immunity to B. pertussis affects B. bronchiseptica infection, and suggest that the high levels of herd immunity against B. pertussis in humans could explain the lack of observed B. bronchiseptica transmission. This could also explain the apparent association of B. bronchiseptica infections with an immunocompromised state
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