28 research outputs found

    Identification of Immunogenic Salmonella enterica Serotype Typhi Antigens Expressed in Chronic Biliary Carriers of S. Typhi in Kathmandu, Nepal

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    Background: Salmonella enterica serotype Typhi can colonize and persist in the biliary tract of infected individuals, resulting in a state of asymptomatic chronic carriage. Chronic carriers may act as persistent reservoirs of infection within a community and may introduce infection to susceptible individuals and new communities. Little is known about the interaction between the host and pathogen in the biliary tract of chronic carriers, and there is currently no reliable diagnostic assay to identify asymptomatic S. Typhi carriage. Methodology/Principal Findings To study host-pathogen interactions in the biliary tract during S. Typhi carriage, we applied an immunoscreening technique called in vivo-induced antigen technology (IVIAT), to identify potential biomarkers unique to carriers. IVIAT identifies humorally immunogenic bacterial antigens expressed uniquely in the in vivo environment, and we hypothesized that S. Typhi surviving in the biliary tract of humans may express a distinct antigenic profile. Thirteen S. Typhi antigens that were immunoreactive in carriers, but not in healthy individuals from a typhoid endemic area, were identified. The identified antigens included a number of putative membrane proteins, lipoproteins, and hemolysin-related proteins. YncE (STY1479), an uncharacterized protein with an ATP-binding motif, gave prominent responses in our screen. The response to YncE in patients whose biliary tract contained S. Typhi was compared to responses in patients whose biliary tract did not contain S. Typhi, patients with acute typhoid fever, and healthy controls residing in a typhoid endemic area. Seven of 10 (70%) chronic carriers, 0 of 8 bile culture-negative controls (0%), 0 of 8 healthy Bangladeshis (0%), and 1 of 8 (12.5%) Bangladeshis with acute typhoid fever had detectable anti-YncE IgG in blood. IgA responses were also present. Conclusions/Significance: Further evaluation of YncE and other antigens identified by IVIAT could lead to the development of improved diagnostic assays to identify asymptomatic S. Typhi carriers

    Computation of semantic similarity within an ontology of breast pathology to assist inter-observer consensus

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    International audienceComputer-assisted consensus in medical imaging involves automatic comparison of morphological abnormalities observed by physicians in images. We built an ontology of morphological abnormalities in breast pathology to assist inter-observer consensus. Concepts of morphological abnormalities extracted from existing terminologies, published grading systems and medical reports were organized in an taxonomic hierarchy and furthermore linked by the relation “is a diagnostic criterion of” according to diagnostic meaning. We implemented position-based, content-based and mixed semantic similarity measures between concepts in this ontology and compared the results with experts’ judgment. The position-based similarity measure using both taxonomic and non-taxonomic relations performed as well as the other measures and was used for automatic comparison of morphological abnormalities within the IDEM computer-assisted consensus platform

    Intégration de multiples ontologies en anatomie pathologique

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    National audienceLa variabilité diagnostique en anatomie pathologique est en partie liée à l'utilisation de systèmes de classification différents, pouvant être considérés comme des points de vue différents, pour décrire des lésions. Notre objectif est de représenter ces points de vue et de proposer une solution pour permettre leur interopérabilité. L'approche hybride décrite par Wache nous permet de développer un système multi ontologique en trois étapes 1) la représentation des points de vue au sein d'ontologies locales, 2) la construction d'un vocabulaire partagé et 3) le développement d'un outil de traduction. L'évaluation du travail, conduite sur 33 cas, a consisté à évaluer les ontologies locales grâce à un outil de validation sémantique de cas et à évaluer l'outil de traduction. Nos résultats montrent que les pathologistes produisent des descriptions qui ne suivent pas toujours les règles d'interprétation des systèmes de classification auxquels ils se réfèrent. Si 62.5% à 100% des concepts des ontologies locales sont traduisibles, nous avons constaté que la validité des cas n'était pas toujours conservée après traduction
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