1,721,085 research outputs found
Epidemiology of Staphylococcus aureus intestinal colonization
No full textLa colonisation digestive à Staphylococcus aureus est mal connue avec des travaux portant majoritairement sur la colonisation à S. aureus résistant à la méticilline. Elle est majoritairement associée à une colonisation nasale mais peut aussi être retrouvée de manière exclusive chez les porteurs. La détection de ce portage n’est pas standardisée et les données concernant sa physiopathologie sont rares. L’origine de cette colonisation reste mal définie et l’interrelation avec la colonisation nasale est peu étudiée notamment chez les patients colonisés avec des souches de S. aureus sensible à la méticilline (SASM). Contrairement à la colonisation nasale dont l’impact clinique est bien décrit, l’impact clinique de ce réservoir en association ou non avec le réservoir nasal est peu étudié. Nous avons montré, chez des patients de réanimation, qu’il existe une diversité génétique entre les souches de SASM isolées des muqueuses nasales et rectales chez un même individu et nous avons également décrit un cas d’infection endogène chez un porteur au niveau digestif exclusif suggérant un rôle de ce réservoir dans les infections à S. aureus. Nous avons identifié, chez des patients communautaires bénéficiant d’une colonoscopie, la localisation de S. aureus au niveau de biopsies coliques suggérant sa présence au niveau de la muqueuse intestinale. De plus nous avons mis en évidence un rôle de la préparation colique dans la décolonisation de S. aureus au niveau de plusieurs sites de portage. Enfin nos travaux ont également montré que, comparé au dépistage nasal seul, le dépistage du portage digestif de S. aureus permettait de dépister jusqu’à 17% de porteurs en plus.Despite first description in the literature in the 1960s, Staphylococcus aureus intestinal colonization is not well known. Previous works mainly investigated the carriage of methicillin-resistant S. aureus. Overall, S. aureus intestinal colonization is associated with S. aureus nasal one but exclusive intestinal carriers are also described. The screening of this carriage is not standardized and different hypotheses about its physiopathology are debated. However, the origin of this colonization remains unclear and the interrelationship with nasal colonization has been poorly studied, particularly in patients colonized with methicillin-sensitive strains of S. aureus (MSSA). Unlike S. aureus nasal colonization, whose clinical impact is well described, the clinical impact of this reservoir in association or not with nose carriage is not well studied. We showed in intensive care unit patients, that there was in a same patient a significant genetic diversity between MSSA strains isolated from nasal and rectal mucosa. We also recorded a case of an endogenous infection in an exclusive rectal carrier suggesting a role of this reservoir during S. aureus infections. During the follow-up of community patients undergoing a colonoscopy, we identified, S. aureus strains in colonic biopsies suggesting the presence of this bacterium in the intestine mucosa. Additionally, we highlighted the potential role of bowel cleansing preparation to decolonize S. aureus carriers at several sites. Finally, compared to nose sampling only, our works showed the adding value of the intestinal screening that would detect up to 17% more S. aureus carriers
Les facteurs de risque de sévérité liés à l'hôte et au traitement au cours de la fièvre boutonneuse méditerranéenne
No full textLa fièvre boutonneuse Méditerranéenne (FBM) est due à Rickettsia conorii subsp. conorii, bactérie intracellulaire stricte. Cette maladie, initialement décrite comme bénigne, présente actuellement un taux de sévérité de l’ordre de 10% avec une augmentation de cette sévérité décrite dernièrement. Au cours d’une étude clinique rétrospective portant sur 161 cas de FBM, nous avons observé que le traitement par fluoroquinolones était associé à une évolution défavorable, ce qui à ce jour n’avait jamais été rapporté, alors que la doxycycline semble être protectrice. Nous avons également observé cet effet délétère des fluoroquinolones sur un modèle in vitro d’infection cellulaire à R. conorii, effet qui n’a pas été observé avec la doxycycline. Une des hypothèses pouvant expliquer cet effet est l’induction du module toxine-antitoxine par les fluoroquinolones. Ainsi nous avons montré que la ciprofloxacine modulait l’expression des gènes du couple toxine-antitoxine. Nous avons également montré que les statines pouvaient avoir un effet prophylactique au cours de l’infection par R. conorii. Enfin nous avons étudié la réponse de l’hôte au sein de l’escarre d’inoculation par une approche transcriptomique.Cette thèse a mis en évidence que les traitements reçus au cours de la FBM peuvent modifier le pronostic de cette maladie. Le choix des antibiotiques est donc crucial et doit faire l’objet d’études complémentaires.Mediterranean spotted fever (MSF) is caused by Rickettsia conorii subsp. conorii, a strict intracellular bacterium. The disease initially described as benign presents currently rates of severity around 10% with an increase described recently. In a retrospective clinical study of 161 cases of MSF, we observed that treatment with fluoroquinolones was associated with an unfavourable outcome whereas doxycycline appeared to be protective. We also observed this deleterious effect of fluoroquinolones in vitro in a cellular model of R. conorii infection, which was not observed with doxycycline. One hypothesis that could explain this effect is the induction of toxin-antitoxin module by fluoroquinolones. Thus we have shown that ciprofloxacin modulates the gene expression of toxin-antitoxin module. We have also shown that statins may have a prophylactic effect during infection by R. conorii. Finally, we have studied the host response within the inoculation eschar by a transcriptomic approach. This thesis has shown that the treatment received during the MSF can change the prognosis of this disease. The choice of antibiotics is crucial, and should be subject to further studies
La diminution de la mortalité au cours des endocardites infectieuses grace à une approche systématique et multidisciplinaire
No full textAIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Emerg Infect Dis
No full textDuring January 2010, a husband and wife returned from Laos to France with probable parasitic disease. Increased antibodies against an Acanthamoeba polyphaga mimivirus virophage indicated seroconversion. While in Laos, they had eaten raw fish, a potential source of the virophage. This virophage, associated with giant viruses suspected to cause pneumonia, could be an emerging pathogen
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Full text linkWe 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
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