1,259 research outputs found

    Induction of humoral immunity with plasmid DNA encoding an immunogenic fragment of Pasteurella haemolytica A1 leukotoxin

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    Pneumonic pasteurellosis is an acute respiratory disorder that results from infection of the bovine lung by Pasteurella haemolytica A1. The primary virulence determinant is a secreted, ruminant-specific leukotoxin (LktA). The leukotoxin is a pore forming toxin that promotes inflammation and bacterial proliferation in the airways of infected animals. Studies continue to show that leukotoxin-neutralizing antibodies are required for significant levels of protective immunity. This laboratory has focused on characterizing this toxin in an attempt to define important immunogenic epitopes which could be incorporated into an effective vaccine. These studies were undertaken to explore the ability of a novel vaccination approach to elicit protective leukotoxin-specific antibodies in immunized mice. A plasmid encoding the immunogenic LktA fragment corresponding to amino acids 715-953 was used in a DNA-based vaccine and was examined for its efficacy in generating a leukotoxin-specific immune response in mice. In addition, the potential immunostimulatory peptides, human IL-1β 163-171 and human acidic isoferritin 172-185, were incorporated into DNA-based vaccines and into GSTfusion- protein vaccines, and monitored for the ability to augment the developing antibody response. Results from these studies indicated 1) the leukotoxin-encoding plasmid used in DNA-based vaccination is capable of generating protein-specific antibodies, however, these antibodies are not neutralizing; 2) the adjuvant peptides are capable of augmenting the immune response when incorporated in a DNA-based vaccine, although they do not contribute to the development of neutralizing antibodies; and 3) the adjuvant peptides do not display immunostimulatory effects when incorporated between the GST moiety and the LktA fragment in recombinant protein vaccines

    Neisseria cinerea Expresses a Functional Factor H Binding Protein Which Is Recognized by Immune Responses Elicited by Meningococcal Vaccines

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    Neisseria meningitidis is a major cause of bacterial meningitis and sepsis worldwide. Capsular polysaccharide vaccines are available against meningococcal serogroups A, C, W, and Y. More recently two protein-based vaccines, Bexsero and Trumenba, against meningococcal serogroup B strains have been licensed; both vaccines contain meningococcal factor H binding protein (fHbp). fHbp is a surface-exposed lipoprotein that binds the negative complement regulator complement factor H (CFH), thereby inhibiting the alternative pathway of complement activation. Recent analysis of available genomes has indicated that some commensal Neisseria species also contain genes that potentially encode fHbp, although the functions of these genes and how immunization with fHbp-containing vaccines could affect the commensal flora have yet to be established. Here, we show that the commensal species Neisseria cinerea expresses functional fHbp on its surface and that it is responsible for recruitment of CFH by the bacterium. N. cinerea fHbp binds CFH with affinity similar to that of meningococcal fHbp and promotes survival of N. cinerea in human serum. We examined the potential impact of fHbp-containing vaccines on N. cinerea. We found that immunization with Bexsero elicits serum bactericidal activity a gainst N. cinerea, which is primarily directed against fHbp. The shared function of fHbp in N. cinerea and N. meningitidis and cross-reactive responses elicited by Bexsero suggest that the introduction of fHbp-containing vaccines has the potential to affect carriage of N. cinerea and other commensal species

    ICPSR Working Paper 2

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    This report reviews best practices for using data resources from ICPSR, its projects, and its collaborating partners for measuring the impact of epidemics. The report summarizes resources to identify measures of well-being, social connectedness, and other constructs to measure the social and behavioral effects of the COVID-19 epidemic on population health outcomes. The report suggests data resources to identify pre-crisis measures of social distancing, social networks, consumer confidence, unemployment, and the use of social media.https://deepblue.lib.umich.edu/bitstream/2027.42/154682/1/Best Practices Measuring Impact of Epidemics Version April 3, 2020.pdfDescription of Best Practices Measuring Impact of Epidemics Version April 3, 2020.pdf : White pape

    Ontogenetic Investigation of Underwater Hearing Capabilities in Loggerhead Sea Turtles (Caretta caretta) Using a Dual Testing Approach

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    Sea turtles reside in different acoustic environments with each life history stage and may have different hearing capacity throughout ontogeny. For this study, two independent yet complementary techniques for hearing assessment, i.e. behavioral and electrophysiological audiometry, were employed to (1) measure hearing in post-hatchling and juvenile loggerhead sea turtles Caretta caretta (19-62 cm straight carapace length) to determine whether these migratory turtles exhibit an ontogenetic shift in underwater auditory detection and (2) evaluate whether hearing frequency range and threshold sensitivity are consistent in behavioral and electrophysiological tests. Behavioral trials first required training turtles to respond to known frequencies, a multi-stage, time-intensive process, and then recording their behavior when they were presented with sound stimuli from an underwater speaker using a two-response forced-choice paradigm. Electrophysiological experiments involved submerging restrained, fully conscious turtles just below the air-water interface and recording auditory evoked potentials (AEPs) when sound stimuli were presented using an underwater speaker. No significant differences in behavior-derived auditory thresholds or AEP-derived auditory thresholds were detected between post-hatchling and juvenile sea turtles. While hearing frequency range (50-1000/1100 Hz) and highest sensitivity (100-400 Hz) were consistent in audiograms pooled by size class for both behavior and AEP experiments, both post-hatchlings and juveniles had significantly higher AEP-derived than behavior-derived auditory thresholds, indicating that behavioral assessment is a more sensitive testing approach. The results from this study suggest that post-hatchling and juvenile loggerhead sea turtles are low-frequency specialists, exhibiting little differences in threshold sensitivity and frequency bandwidth despite residence in acoustically distinct environments throughout ontogeny

    Exploring health professionals’ and women's awareness of models of maternity care evidence

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    A Cochrane systematic review has shown midwife-led continuity models of care provide explicit benefits for mothers and babies compared with other models of maternity care, with a comparable level of safety. The Cochrane review has had much international impact. This study explored the local impact of the review, alongside other midwife-led care evidence and guidelines. Electronic surveys were undertaken exploring women's and health professionals' awareness of models of maternity care evidence, including midwife-led care and homebirth, and how they utilise evidence to guide their choices and practice. A low awareness of much of the available evidence was shown among the women and the professionals. There is a need for better dissemination of information to professionals as they are women's preferred source of information about the options available for place of birth and midwife-led care

    How does Labrador Sea Water enter the deep western boundary current?

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    Author Posting. © American Meteorological Society, 2008. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 38 (2008): 968-983, doi:10.1175/2007JPO3807.1.Labrador Sea Water (LSW), a dense water mass formed by convection in the subpolar North Atlantic, is an important constituent of the meridional overturning circulation. Understanding how the water mass enters the deep western boundary current (DWBC), one of the primary pathways by which it exits the subpolar gyre, can shed light on the continuity between climate conditions in the formation region and their downstream signal. Using the trajectories of (profiling) autonomous Lagrangian circulation explorer [(P)ALACE] floats, operating between 1996 and 2002, three processes are evaluated for their role in the entry of Labrador Sea Water in the DWBC: 1) LSW is formed directly in the DWBC, 2) eddies flux LSW laterally from the interior Labrador Sea to the DWBC, and 3) a horizontally divergent mean flow advects LSW from the interior to the DWBC. A comparison of the heat flux associated with each of these three mechanisms suggests that all three contribute to the transformation of the boundary current as it transits the Labrador Sea. The formation of LSW directly in the DWBC and the eddy heat flux between the interior Labrador Sea and the DWBC may play leading roles in setting the interannual variability of the exported water mass.We are also grateful to the NSF for their support of this research

    The Perceptions And Experiences Of Women With A Body Mass Index ≥ 30 kg m2 Who Breastfeed: A Meta-synthesis

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    Breastfeeding has copious health benefits for both mother and child, but rates of initiation and maintenance amongst women with a BMI ≥30kg/m2 are low. Few interventions aiming to increase these rates have been successful, suggesting that breastfeeding behaviour in this group is not fully understood. Therefore, this review aimed to systematically identify and synthesise the qualitative literature which explored the perceptions and experiences of women with a BMI ≥30kg/m2 who breastfed. The search identified five eligible papers, and a meta-ethnographic approach was taken to synthesise the findings. One theme was identified: ‘weight amplifies breastfeeding difficulties’, revealing that women with a BMI ≥30kg/m2 experience common breastfeeding difficulties to a greater degree. In particular, women with a BMI ≥30kg/m2 struggle with the impact of medical intervention, doubt their ability to breastfeed, and need additional support. These findings can inform understanding of breastfeeding models, future research directions, intervention development and antenatal and postnatal care for women with a BMI ≥30kg/m2

    Independent and Interactive Associations of Negative Affect, Restraint, and Impulsivity in Relation to Binge Eating Among Women

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    There is growing recognition that impulsivity may serve as an underlying risk factor for binge eating. In addition, the association of impulsivity with binge eating may be moderated by other affective and cognitive risk factors. This study examined independent and interactive associations of negative affect, dietary restraint, and facets of impulsivity with binge eating. A diverse sample of 566 undergraduate women completed online questionnaires of study variables. Results revealed a three-way interaction of negative affect, dietary restraint, and attentional impulsivity in relation to binge eating. Women who were high on each of these three variables reported the greatest levels of binge eating. In addition, a two-way interaction was found for negative affect and nonplanning impulsivity in relation to binge eating, such that nonplanning impulsivity strengthened the association between negative affect and binge eating. Attentional and nonplanning facets of impulsivity may function as an underlying trait-level risk factor interacts with affective and/or cognitive risk (e.g., negative affect, dietary restraint) factors to predict elevated binge eating
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