1,720,991 research outputs found

    Homologous prime boosting based on intranasal delivery of non-pathogenic invasive Escherichia coli expressing MPT64, decreases Mycobacterium tuberculosis dissemination

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    Protein-subunit vaccines as boosting strategies against tuberculosis (TB) infection are currently in the pipeline of TB vaccine research. Their main limitation is represented by their poor immunogenicity, which makes it necessary to couple protein-subunits with adjuvant molecules. In this study, we employed replication-deficient invasive Escherichia coli strains to deliver Mycobacterium tuberculosis proteins to the cytoplasm of non-phagocytic eukaryotic cells using various priming and prime-boosting vaccination protocols. Our results demonstrate that intranasal administration of invasive E. coli expressing the M. tuberculosis protective antigen MPT64 to mice primed with a recombinant BCG strain over-expressing MPT64 on its surface, decrease bacterial burden in mice spleens. Our data suggest that replication-deficient invasive E. coli may represent a suitable platform for BCG/rBCG priming followed by homologous-boosting immunization strategies

    Recombinant paramysin (rec-Sj-97) tested for immunogenicity and vaccine efficacy against Schistosoma japonicum in mice and water buffaloes

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    A primary vaccine candidate antigen against schistosomiasis is paramyosin (pmy), a myofibrillar protein found exclusively in invertebrates. Here we report the results of vaccine trials against the Asian schistosome undertaken on inbred and outbred mice and water buffaloes using a bacterially expressed and purified form of Schistosoma japonicum pmy (rec-Sj-97). Vaccination of the mice resulted in high levels of specific anti-pmy IgG antibodies when compared with adjuvant controls and significant reduction in worm burdens and in liver eggs. Furthermore, a significant reduction in liver eggs was recorded in two of the three water buffalo vaccine trials undertaken and, in all three trials, high levels of specific anti-pmy IgG antibodies were generated. There was no evidence of any toxic effects and the vaccine preparations and Quil A adjuvant were clearly well tolerated. The development of a vaccine intended for livestock animals such as bovines would be beneficial in two ways; directly by blocking transmission of schistosomiasis to humans and economically by contributing to healthier livestock. We are encouraged by the consistent efficacy in the mouse and the buffalo vaccine trials that resulted in a significant decrease in liver eggs. Indeed, predictions from mathematical models indicate that an egg reduction effect of 42-45% in buffaloes would be sufficient when combined with human treatment to control schistosomiasis japonica in the marshes and lakes along the middle and upper reaches of the Yangtze River, the most highly endemic areas for the disease in China

    Differential distribution of ammonia- and nitrite-oxidising bacteria in flocs and granules from a nitrifying/denitrifying sequencing batch reactor

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    A lab-scale sequencing batch reactor was operated with alternating anoxic/aerobic conditions for nitrogen removal. Flocs and granules co-existed in the same reactor, with distinct aggregate structure and size, for over 180 days of reactor operation' Process data showed complete nitrogen removal, with temporary nitrite accumulation before full depletion of ammonia in the aerobic phase. Microbial quantification of the biomass by fluorescence in situ hybridisation showed that granules contained most of the nitrite-oxidising bacteria (NOB) whereas the ammonium-oxidising bacteria (AOB) seemed to be more abundant in the flocs. This was supported by microsensor measurements, which showed a higher potential of NO2- uptake than NH4 uptake in the granules. The segregation is possibly linked to the different growth rates of the two types of nitrifiers and the reactor operational conditions, which produced different sludge retention time for flocs and granules. The apparent physical separation of AOB and NOB in two growth forms could potentially affect mass transfer of NO2- from AOB to NOB, but the data presented here shows that it did not impact negatively on the overall nitrogen removal. (c) 2006 Elsevier Inc. All rights reserved

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Immune responses to ISCOM (R) formulations in animal and primate models

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    ISCOMs(R) are typically 40 nm cage-like structures comprising antigen, saponin, cholesterol and phospholipid. ISCOMs(R) have been shown to induce antibody responses and activate T helper cells and cyrolytic T lymphocytes in a number of animal species, including non-human primates. Recent clinical studies have demonstrated that ISCOMs(R) are also able to induce antibody and cellular immune responses in humans. This review describes the current understanding of the ability of ISCOMs(R) to induce immune responses and the mechanisms underlying this property. Recent progress in the characterisation and manufacture of ISCOMs(R) will also be discussed. (C) 2001 Elsevier Science Ltd. All rights reserved

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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