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Optimiser la validité des comportements observés sur simulateur de conduite : étude des interactions entre immersion, présence et comportement / Optimizing the validity of behaviors observed on driving simulator : study of the interactions between immersion, presence and behaviorDeniaud, Christophe 08 December 2017 (has links)
Les simulateurs de conduite permettent d’étudier le comportement humain dans différentes conditions fixées expérimentalement. Un avantage majeur de la simulation est de ne pas exposer le sujet à un risque objectif et que les conditions de test sont "facilement" mises en œuvre et manipulées. Le recours à la simulation pose néanmoins la question de la généralisation et transposition des comportements observés en simulation à la situation réelle de conduite. En effet, il est nécessaire de s’assurer que le simulateur mesure précisément l’objet d’étude sans le modifier ou l’influencer. L’évaluation du degré de validité est donc cruciale dans toute étude sur simulateur qui cherche à susciter des comportements réalistes de conducteurs. Le postulat de notre travail repose donc sur l’idée que la présence est un concept clé pour évaluer la représentativité des comportements de conduite observés en simulation. Toutefois plusieurs difficultés seront à résoudre. Une des plus cruciales repose sur le fait que la présence est difficilement mesurable en temps réel puisque le fait même de chercher à la mesurer peut rompre l’état de présence plus ou moins existant. Ainsi obtenir des indicateurs comportementaux de la présence constitue un véritable enjeu pour caractériser la nature d’un phénomène qui à l’heure actuelle est davantage fantasmé à l’aide de mesures post-expérimentation que concrètement démontré par la mise en évidence de comportements spécifiques reproductibles. / Driving simulators make it possible to study human behavior in different experimentally determined conditions. A major benefit of simulation is that it does not expose the subject to an objective risk and that test conditions are "easily" implemented and manipulated. The use of simulation nevertheless raises the question of the generalization and transposition of the behaviors observed in simulation to the actual driving situation. Indeed, it is necessary to ensure that the simulator accurately measures the object of study without modifying or influencing it. Assessing the degree of validity is therefore crucial in any simulator study that seeks to create realistic driver behaviors. The postulate of our work is therefore based on the idea that presence is a key concept for assessing the representativeness of driving behaviors observed in simulation. However, several difficulties will have to be solved. One of the most crucial is the fact that presence is difficult to measure in real time because the very fact of trying to measure it can break the more or less existing presence state. Thus, to obtain behavioral indicators of presence is a real challenge to characterize the nature of a phenomenon which at present is more fantasized by post-experimental measures than concretely demonstrated by the demonstration of specific reproducible behaviors.
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Neužitečné věci / Useless ThingsMaloušková, Drahomíra Unknown Date (has links)
Useless things. I normally use trash things like pattern in painting still life. My father suffers from obsessive compulsive disorder – accumulation of things. In addition to painting, I also work with objects themselves. My interest also closely related to how the concepts of the subject, object and artifact are appliing in contemporary art. There are the tradition of imitation fact, principle of ready-made, the issue of technical reproducibility and virtual reality of things in history of art. As a central theme of my thesis, I selected the part of bodywork Tatra 613, which carries all the testimony about ,,useless and hopeless "situation in which it is located. It is also an object monumental and visually very aesthetic. Yet it is not my intention to settle for the principle of redy-made. Asked about artwork as intermediaries art and its seemingly useless producing and reproducing, I want to try to create another such usless situation. That's why I make a cardboard copy (1: 1) of this object. I also make video with motive 3D copy of the same object. I like to create some voltage between that useless object and valuable art practice. I think, it does not just mean such futility when these objects will be viewed as an art.
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Přeshraniční srovnávací analýza motorických schopností dětí mladšího školního věku - pilotní studieBenešová, Daniela, Lange, Uwe, Oelze, Janine, Salcman, Václav, Schulz, Henry, Schuster, Simone, Valach, Petr January 2014 (has links)
Vzrůstající nedostatek pohybu dětí a mladistvých v průmyslových státech se v minulých desetiletích rozvinul ve zdravotně-politický problém. V souladu s touto problematikou zároveň klesá i úroveň motorických schopností a dovedností, což představuje citelné omezení dětského vývoje, fyzické i psychické komponenty. Důsledkem jsou rostoucí náklady na zdravotní péči, které posléze výrazně zatěžují zdravotnictví v jednotlivých zemích. Cílem vědeckých týmů Západočeské Univerzity v Plzni a Technické Univerzity Chemnitz je v rámci pilotní studie pod názvem „Přeshraniční srovnávací analýza motorických schopností dětí mladšího školního věku“ stanovit a porovnat aktuální zdravotní situaci školáků v České republice a Německu. / Der gestiegene Bewegungsmangel der Kinder und Jugendlichen in den Industriestaaten hat sich in den vergangenen Jahrzehnten zu einem gesundheitspolitischen Problem entwickelt. Das darüber hinaus sinkende Niveau motorischer Fähigkeiten und Fertigkeiten zieht Beeinträchtigungen der kindlichen Entwicklung auf physischer und psychischer Ebene mit entsprechenden Folgekosten für die Gesundheitssysteme der Länder nach sich. Die Wissenschaftler der Westböhmischen Universität Pilsen und der Technischen Universität Chemnitz haben sich aus diesem Grund zum Ziel gesetzt, in der Pilotstudie „Grenzüberschreitende Vergleichsanalyse der motorischen Fähigkeiten von Kindern des jüngeren Schulalters“ die gesundheitliche Situation von Schulanfängern in der Tschechischen Republik und in Deutschland zu untersuchen und gegenüber zu stellen. / The increased sedentary lifestyle of children and adolescents in industrialized countries has evolved into a public health problem over the past decades. In addition, the declining level of motor abilities and skills draws impairment of children development on physical and psychological level, with appropriate follow-up costs for the health systems of countries. Scientists at the University of West Bohemia Pilsen and the Chemnitz University of Technology have for this reason the goal to investigate and to contrast the health situation of children starting school in the Czech Republic and in Germany with the pilot study "Cross-border comparative analysis of the motor skills of children of younger school age".
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Gesundheitsrelevante Charakteristika von Führung an Hochschulen aus Mitarbeiter- und Vorgesetztenperspektive: Eine Untersuchung des wissenschaftlichen und nicht-wissenschaftlichen Personals am Fallbeispiel einer Technischen UniversitätRöhr, Kristin Helga 13 April 2021 (has links)
Innerhalb der vorliegenden Arbeit wurden die gesundheitsrelevanten Charakteristika von Führung an Hochschulen aus Mitarbeiter- und Vorgesetztenperspektive untersucht. Auf Grundlage einer umfassenden einleitenden Betrachtung des Forschungsstandes zu den Themen Führung und Gesundheit, sowie der Betrachtung der Studienlage zu Führungsfaktoren an Hochschulen zeigt sich u.a., dass Vorgesetzte in vielerlei Hinsicht eine Schlüsselposition bei der Gesunderhaltung ihrer Mitarbeitenden einnehmen. Die theoretische Auseinandersetzung mit dem direkten und indirekten Führungseinfluss und den bestehenden Modellen zur gesundheitsförderlichen Führung ergab die Identifikation von intra- und interindividuellen Faktoren der Selbst- und Mitarbeiterführung. Zudem konnten vielfältige führungsseitige strukturelle und personelle Einflussmöglichkeiten im Hinblick auf die Arbeits- und Organisationsgestaltung und die Bereichskultur aufgezeigt werden. Innerhalb des empirischen Teils der Arbeit wurde das entwickelte Modell mittels verschiedener Analyseinstrumente der qualitativen Sozialforschung, einer schrittweisen induktiven Erweiterung und einer gleichzeitigen Spezifizierung für den Hochschulkontext unterzogen. Innerhalb des sich anschließenden Diskussionsteils wurden die Forschungsfragestellungen näher beleuchtet und methodische Limitationen erörtert. Die Arbeit schließt mit der Generierung von Implikationen für die Führungspraxis der hochschulbezogenen wissenschaftlichen und nicht-wissenschafflichen Bereiche.:1 Einleitung
2 Theoretischer Bezugsrahmen
3 Methodik
4 Ergebnisse
5 Diskussion
6 Schlussbetrachtungen
7 Anhang / In the present work, the health-related characteristics of leadership at universities were examined from the perspective of employees and superiors. Based on a comprehensive examination of the state of research on the topics of leadership and health, as well as management factors at universities, it has been shown that superiors play a key role in keeping their employees healthy in different ways. The theoretical examination of the direct and indirect influence of leadership and the existing models for health-promoting leadership resulted in the identification of intra- and inter-individual factors of self-leadership and employee leadership. In addition, it was also possible to identify a wide range of management-related structural and personnel influence options with regard to work and organizational design and culture within different areas of the university. Within the empirical part of the work, the developed model was subjected to a step-wise inductive expansion and a simultaneous specification for the university context using various analytical instruments of qualitative social research. In the subsequent discussion, the research questions are examined in more detail and methodological limitations are discussed. The work concludes with the generation of implications for management practice in university-related scientific and non-scientific areas.:1 Einleitung
2 Theoretischer Bezugsrahmen
3 Methodik
4 Ergebnisse
5 Diskussion
6 Schlussbetrachtungen
7 Anhang
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Application of the FITT framework to evaluate a prototype health information systemHonekamp, Wilfried, Ostermann, Herwig 24 June 2011 (has links)
We developed a prototype information system with an integrated expert system for headache patients. The FITT (fit between individual, task and technology) framework was used to evaluate the prototype health information system and to determine which deltas to work on in future developments. We positively evaluated the system in all FITT dimensions. The framework provided a proper tool for evaluating the prototype health information system and determining which deltas to work on in future developments.
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Angeleitete internetbasierte Patienteninformation: Studie zur Effektivität eines Informationssystems für KopfschmerzpatientenHonekamp, Wilfried 14 June 2011 (has links)
Eine stetig wachsende Zahl von Nutzern sucht im Internet nach Gesundheitsinformationen. Hierzu steht ihnen eine Vielzahl ganz unterschiedlicher Anbieter zur Verfügung, die bei divergierenden Interessen gesundheitsrelevante Angebote im Internet vorhalten. Abgesehen von der Informationsflut, mit der die Nutzer bei der Suche überhäuft werden, erhalten sie auch falsche, irreführende, veraltete und sogar gesundheitsgefährdende Informationen. In den letzten zehn Jahren haben verschiedene Wissenschaftler die Anforderungen an ein ideales Gesundheitsinformationssystem ermittelt. Im Rahmen des in diesem Beitrag beschriebenen Projekts wurde ein Gesundheitsinformationssystem
als Prototyp zur anamnesebezogenen, internetbasierten Patienteninformation entwickelt und anhand einer Studie evaluiert. Dabei wird die Untersuchung auf deutschsprachige Erwachsene mit Kopfschmerzen eingegrenzt. Insgesamt wird die Hypothese überprüft, dass eine angeleitete, anamnesebezogene Internetsuche für den Patienten bessere Ergebnisse liefert, als dies durch die herkömmliche Nutzung von Gesundheitsportalen oder Suchmaschinen erreicht werden kann.
Zur Evaluation wurde eine kontrollierte Zweigruppenstudie mit insgesamt 140 Teilnehmern in zwei Studienabschnitten durchgeführt. Dabei wurde im ersten Abschnitt festgestellt, dass bei einfach strukturierten Krankheitsfällen das Informationssystem gleichgute Ergebnisse liefert wie die herkömmliche Suche. Im zweiten Abschnitt konnte allerdings festgestellt werden, dass bei komplexen Kopfschmerzfällen mit Hilfe des Prototyps signifikant (P=0,031) bessere Diagnosen gestellt werden konnten als ohne. Medizinische Expertensysteme in Kombination mit einer Meta-Suche nach maßgeschneiderten qualitätsgesicherten Informationen erweisen sich als probate Möglichkeit, den Ansprüchen an eine geeignete Versorgung mit Gesundheitsinformationen gerecht zu werden. / A steadily increasing number of users search for health information online. Therefore, a multitude of totally different providers with diverging interests offer information. Apart from the information overload the users are flooded with, they may access false, misleading or even life threatening information. In the last 10 years scientists have determined the requirements of an ideal health information system.
In the study described in this paper a prototype health information system providing anamnesis related internet-based consumer health information is evaluated. In total, the hypothesis that a computer-aided anamnesis-related internet search provides better results than the use of conventional search engines or health portals is evaluated.
For evaluation a randomised controlled study with 140 participants has been conducted in two study sections. In the first section it was found, that for a less complex diagnosis the prototype information system did equally well as the conventional information retrieval. In the second study section it was found, that dealing with complex headache cases participants using the prototype determined significantly better (P=0.031) diagnoses than the control group did without prototype support.
It has been shown, that medical expert systems in combination with a meta-search for tailored quality controlled information represents a feasible strategy to provide reliable health information.
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An assets based approach to health promotion with young people in EnglandFenton, Catherine Meghan January 2013 (has links)
Introduction The health of young people in England is an area of concern, nationally and internationally. This has prompted a range of strategies and policies to try to address how health may be improved. However, there has not necessarily been agreement as to how this should best be done. There appeared a case for consideration of alternative or additional approaches to health promotion. Aim This research aimed to construct an assets based model to shape health promotion practice and policy for young people in England. Methods A narrative synthesis was undertaken and highlighted the lack of information regarding which assets might be important for young people’s health in England. This programme of research was developed from those initial findings. Quantitative and qualitative methods were employed to gain a more comprehensive understanding than could be gained by individual methods. This mixed methods research involved secondary data analysis of the Health Behaviours in School Aged Children (HBSC) dataset using regression analysis to identify the assets associated with life satisfaction for English youth. Focus groups and interviews were employed to capture the views of young people regarding assets, health and health promotion. Findings were discussed with practitioners to gather their ideas as to the potential of an assets approach. The different research methods were drawn together by the underpinning theoretical frameworks provided by Assets models and the New Social Studies of Childhood. Results Two themes emerged from the narrative synthesis providing suggestions for health promotion; the ecological approach acknowledged the range of settings that young people inhabit, whilst the holistic approach recognised the interrelationship between risks and assets. Critical discussion consolidated the research findings to propose a list of health promoting assets for young people in England; constructive relationships, safety, positive attributes, independence and opportunity. These findings were brought together into a descriptive model to guide health promotion policy and practice (Figure 1). Constructive relationships appeared as a core asset, providing a foundation from which young people could develop. Having positive attributes was also fundamental to this process, which emphasises the importance of promoting physical and mental health simultaneously. Safety was the third core asset identified through the research strands. There was variation between young people regarding the definition of, and priority assigned to, the additional assets of independence and opportunity. Figure 1: Assets model to shape health promotion with young people Conclusion This research contributes to previous work in the field of assets models by providing new insight into the relatively little researched area of assets approaches to health promotion with young people in England. The complex interrelationships between mental health and assets have been highlighted; providing challenge to frameworks that focus on the quantitative accumulation of assets. The inclusion of young people’s perspectives provided new depth to previous theoretical models and interpretation of quantitative findings. The variation highlighted within this research raises implications for tackling health inequalities. This assets based model provides a framework to shape professional practice and policy thus providing the potential to improve young people’s health and wellbeing in a sustainable and non-stigmatising way.
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Bases mécanistiques des effets d'un insecticide agrovétérinaire, le fiproni, et/ou de ses métabolites sur la fonction thyroïdienne chez le rat / Mechanistic basis of the effects of an agroveterinary insecticide, the fipronil, and/or its metabolites on the thyroid function in ratRoques, Beatrice 12 December 2012 (has links)
Le fipronil, insecticide largement utilisé, est un perturbateur thyroïdien chez le rat modulant le catabolisme hépatique des hormones thyroïdiennes. Ses effets chez le mouton, considéré comme un modèle plus pertinent que le rat pour étudier une régulation de la fonction thyroïdienne chez l'Homme, sont plus limités. Le but de cette thèse était de caractériser au niveau hépatique le mode d'action du fipronil sur la fonction thyroïdienne en s'intéressant 1) au rôle potentiel du principal métabolite du fipronil formé in vivo, le fipronil sulfone, et 2) aux différences interspécifiques de métabolisme du fipronil et/ou de sensibilité à la perturbation thyroïdienne qui peuvent préjuger de la pertinence des différents modèles animaux pour l'analyse du risque du fipronil pour la santé humaine. L'efficacité du fipronil sulfone à induire l'expression et/ou l'activité d'enzymes responsables du métabolisme hépatique des hormones thyroïdiennes ou du fipronil était la même que celle du fipronil autant in vivo chez le rat que in vitro sur hépatocytes. L'utilisation d'un modèle de souris déficientes pour des récepteurs nucléaires xénosenseurs suggérait fortement une implication des récepteurs nucléaires Constitutive Androstane Receptor et/ou Pregnane X Receptor dans la perturbation thyroïdienne induite par le fipronil / The widely used insecticide fipronil is a thyroid disruptor in rat acting on thyroid hormone hepatic metabolism. In sheep, a more relevant species for the human thyroid regulation, fipronil-induced thyroid-disruption is much more limited. The goal of this thesis was to characterize the mode of action of fipronil on thyroid function at the hepatic level focusing on 1) the potential role of fipronil sulfone, the main fipronil metabolite formed in vivo, and on 2) interspecific differences in terms of fipronil metabolism and/or sensitivity to thyroid disruption that can prejudge of the relevance of the different animal models for the risk assessment of fipronil for human health. Fipronil sulfone was as efficient as fipronil to induce the expression and/or activity of enzymes involved in thyroid hormone or fipronil hepatic metabolism both in vivo in rat and in vitro on hepatocytes. The use of knock-out mice for xenosensors nuclear receptors strongly suggested an implication of the nuclear receptor Constitutive Androstane Receptor and/or Pregnane X Receptor on fipronil-induced thyroid disruption
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Outils d'évaluation d'une intervention d'éducation pour la santé environnementale périnatale / Assessment tools of a perinatal environmental health education interventionRouillon, Steeve 11 September 2018 (has links)
De nombreuses affections chez l’enfant et l’adulte sont associées à une exposition in utero à des perturbateurs endocriniens (PE). Pour réduire cette exposition, des programmes d’éducation pour la santé environnementale périnatale se développent. Ils font évoluer des dimensions psychosociales que sont la perception du risque (PR) et la croyance en l’action de réduction de l’exposition (CAR), mais peu d’entre eux sont évaluésL’étude de recherche interventionnelle PREVED a pour objectif d’évaluer l’efficacité d’un programme d’éducation pour la santé environnementale pour des femmes enceintes, visant à diminuer leur exposition aux PE.Les objectifs de ces travaux métrologiques étaient de développer des outils (i) analytiques et (ii) épidémiologiques en vue d’évaluer l’efficacité du programme. Ainsi, (i) des méthodes analytiques ultrasensibles par LC-MS/MS permettant de doser les fractions non conjuguées de PE dans les urines et le colostrum ont été développées et validés sur des prélèvements recueillis dans le cadre de la cohorte périnatale EDDS; (ii) un questionnaire psychosocial explorant la PR, la CAR et les connaissances des femmes enceintes au moyen de scores a été conçu.Ces travaux s’inscrivent dans une approche interdisciplinaire de santé environnementale. Ils proposent des méthodes analytiques fiables pour mesurer l’exposition aux PE étudiés d’une part, et un questionnaire évaluant connaissances, attitudes et pratiques des femmes enceintes sur la question des PE d’autre part. Ces outils permettront de mesurer l’impact du programme d’éducation pour la santé environnementale périnatale. / Childhood and adulthood diseases are associated to in utero exposure to endocrine disrupting chemicals (EDCs). To reduce this exposure, environmental health education programs dedicated to perinatal period are implemented. These programs change psychosocial dimensions such as risk perception (RP) and belief in the action of exposure reduction (BAR), but few are assessed.The interventional research PREVED study aims to assess efficacy of a perinatal environmental health education program to reduce pregnant women exposure to EDC.The objectives of this work were to develop analytical (i) and (ii) epidemiological tools to evaluate the efficacy of the program. Thus, (i) ultrasensitive LC-MS/MS analytical methods were developed to determine unconjugated fractions of EDCs in urine and colostrum and validated using samples collected from the EDDS perinatal cohort; (ii) a psychosocial questionnaire exploring RP, BAR and knowledge of pregnant women by means of scores was developed.This work, part of an interdisciplinary approach to environmental health, proposes reliable analytical methods to assess exposure to the studied EDCs on the one hand, and a questionnaire assessing knowledge, attitudes and practices of pregnant women about EDCs on the other hand. The impact of the perinatal environmental health education program will be assessed using these tools.
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Development of molecular-based techniques for the detection, identification and quantification of food-borne pathogensRodríguez Lázaro, David 18 June 2004 (has links)
La presencia de microorganismos patógenos en alimentos es uno de los problemas esenciales en salud pública, y las enfermedades producidas por los mismos es una de las causas más importantes de enfermedad. Por tanto, la aplicación de controles microbiológicos dentro de los programas de aseguramiento de la calidad es una premisa para minimizar el riesgo de infección de los consumidores. Los métodos microbiológicos clásicos requieren, en general, el uso de pre-enriquecimientos no-selectivos,enriquecimientos selectivos, aislamiento en medios selectivos y la confirmación posterior usando pruebas basadas en la morfología, bioquímica y serología propias de cada uno de los microorganismos objeto de estudio. Por lo tanto, estos métodos son laboriosos, requieren un largo proceso para obtener resultados definitivos y, además, no siempre pueden realizarse. Para solucionar estos inconvenientes se han desarrollado diversas metodologías alternativas para la detección identificación y cuantificación de microorganismos patógenos de origen alimentario, entre las que destacan los métodosinmunológicos y moleculares. En esta última categoría, la técnica basada en la reacción en cadena de la polimerasa (PCR) se ha convertido en la técnica diagnóstica más popular en microbiología, y recientemente, la introducción de una mejora de ésta, la PCR a tiempo real, ha producido una segunda revolución en la metodología diagnóstica molecular, como pude observarse por el número creciente de publicaciones científicas y la aparición continua de nuevos kits comerciales. La PCR a tiempo real es unatécnica altamente sensible -detección de hasta una molécula- que permite la cuantificación exacta de secuencias de ADN específicas de microorganismos patógenos de origen alimentario. Además, otras ventajas que favorecen su implantación potencial en laboratorios de análisis de alimentos son su rapidez, sencillez y el formato en tubo cerrado que puede evitar contaminaciones post-PCR y favorece la automatización y un alto rendimiento. En este trabajo se han desarrollado técnicas moleculares (PCR y NASBA) sensibles y fiables para la detección, identificación y cuantificación de bacterias patogénicas de origen alimentario (Listeria spp., Mycobacterium avium subsp. paratuberculosis y Salmonella spp.). En concreto, se han diseñado y optimizado métodos basados en la técnica de PCR a tiempo real para cada uno de estos agentes: L. monocytogenes, L. innocua, Listeria spp. M. avium subsp. paratuberculosis, y también se ha optimizado yevaluado en diferentes centros un método previamente desarrollado para Salmonella spp. Además, se ha diseñado y optimizado un método basado en la técnica NASBA para la detección específica de M. avium subsp. paratuberculosis. También se evaluó la aplicación potencial de la técnica NASBA para la detección específica de formas viables de este microorganismo. Todos los métodos presentaron una especificidad del 100 % con una sensibilidad adecuada para su aplicación potencial a muestras reales de alimentos. Además, se han desarrollado y evaluado procedimientos de preparación de las muestras en productos cárnicos, productos pesqueros, leche y agua. De esta manera se han desarrollado métodos basados en la PCR a tiempo real totalmente específicos y altamente sensibles para la determinación cuantitativa de L. monocytogenes en productoscárnicos y en salmón y productos derivados como el salmón ahumado y de M. avium subsp. paratuberculosis en muestras de agua y leche. Además este último método ha sido también aplicado para evaluar la presencia de este microorganismo en el intestino de pacientes con la enfermedad de Crohn's, a partir de biopsias obtenidas de colonoscopia de voluntarios afectados.En conclusión, este estudio presenta ensayos moleculares selectivos y sensibles para la detección de patógenos en alimentos (Listeria spp., Mycobacterium avium subsp. paratuberculosis) y para una rápida e inambigua identificación de Salmonella spp. La exactitud relativa de los ensayos ha sido excelente, si se comparan con los métodos microbiológicos de referencia y pueden serusados para la cuantificación de tanto ADN genómico como de suspensiones celulares. Por otro lado, la combinación con tratamientos de preamplificación ha resultado ser de gran eficiencia para el análisis de las bacterias objeto de estudio. Por tanto, pueden constituir una estrategia útil para la detección rápida y sensible de patógenos en alimentos y deberían ser una herramienta adicional al rango de herramientas diagnósticas disponibles para el estudio de patógenos de origen alimentario. / The presence of pathogens in foods is among the most serious public health concerns, and the diseases produced by them are a major cause of morbidity. Consequently, the application of microbiological control within the quality assessment programs in the food industry is a premise to minimize the risk of infection for the consumer. Classical microbiological methods involve, in general, the use of a non-selective pre-enrichment, selective enrichment, isolation on selective media, and subsequent confirmation using morphological, biochemical and/or serological tests. Thus, they are laborious, time consuming and not always reliable (e.g. in viable but non-culturable VBNC forms). A number of alternative, rapid and sensitive methods for the detection, identification and quantification of foodborne pathogens have been developed to overcome these drawbacks. PCR has become the most popular microbiological diagnostic method, and recently, the introduction of a development of this technique, RTi-PCR, has produced a second revolution in the molecular diagnostic methodology in microbiology. RTi-PCR is highly sensitive and specific. Moreover, it allows accurate quantification of the bacterial target DNA. Main advantages of RTi-PCR for its application in diagnostic laboratories include quickness, simplicity, the closed-tube format that avoids risks of carryover contaminations and the possibility of high throughput and automation.In this work, specific, sensitive and reliable analytical methods based on molecular techniques (PCR and NASBA) were developed for the detection, identification and quantification of foodborne pathogens (Listeria spp., Mycobacterium avium subsp. paratuberculosis and Salmonella spp.). Real-time PCR based methods were designed and optimised for each one of these target bacteria: L. monocytogenes, L. innocua, Listeria spp. M. avium subsp. paratuberculosis, and also a real-time PCR basedmethod previously described for Salmonella spp. was optimised and multicenter evaluated. In addition, an NASBA-based method was designed and optimised for the specific detection of M. avium subsp. paratuberculosis. The potential application of the NASBA technique for specific detection of viable M. avium subsp. paratuberculosis cells was also evaluated.All the amplification-based methods were 100 % specific and the sensitivity achieved proved to be fully suitable for further application in real food samples. Furthermore, specific pre-amplification procedures were developed and evaluated on meatproducts, seafood products, milk and water samples. Thus, fully specific and highly sensitive real-time PCR-based methods were developed for quantitative detection of L. monocytogenes on meat and meat products and on salmon and cold smoked salmon products; and for quantitative detection of M. avium subsp. paratuberculosis on water and milk samples. The M. avium subsp. paratuberculosis-specific real-time PCR-based method was also applied to evaluate the presence of this bacterium in the bowelof Crohn's disease patients using colonic biopsy specimens form affected and unaffected volunteers. In addition, fully specific and highly sensitive real-time NASBA-based methods were developed for detection of M. avium subsp. paratuberculosis on water and milk samples.In conclusion, this study reports selective and sensitive amplification-based assays for the quantitative detection of foodborne pathogens (Listeria spp., Mycobacterium avium subsp. paratuberculosis and) and for a quick and unambiguously identification of Salmonella spp. The assays had an excellent relative accuracy compared to microbiological reference methods and can be used for quantification of genomic DNA and also cell suspensions. Besides, in combination with sample pre-amplification treatments,they work with high efficiency for the quantitative analysis of the target bacteria. Thus, they could be a useful strategy for a quick and sensitive detection of foodborne pathogens in food products and which should be a useful addition to the range of diagnostic tools available for the study of these pathogens.
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