1,721,012 research outputs found
Profiling the microbiota to develop innovative therapies for infectious diarrhea
No full textGastrointestinal pathogens such as Salmonella, Clostridioides difficile, Campylobacter,
and Shigella are major causes of diarrhea and can significantly disrupt the gut microbiota
composition. The intricate relationship between the microbiota, the host, and invading
pathogens are complex. For example, fecal microbiota transplant (FMT) is the transfer of
donor stool in patients, and is an effective treatment for recurrent C. difficile infections
(rCDi). The success of FMT is often attributed to the restoration of the bacterial community
in patients. Profiling the microbiota using next-generation sequencing techniques provides a
powerful tool to assess compositional changes, offering insights into the dynamic interactions
between the microbiota and disease. This thesis aims to evaluate the compositional changes
in individuals with infectious diarrhea, with the ultimate goal of paving the way for innovative
therapeutic applications.
We hypothesize that the microbiota may play a protective role against symptomatic
Salmonella infections. To investigate this, the virulence of Salmonella strains isolated from
symptomatic and asymptomatic individuals was compared, in addition to their bacterial
profiles and those of healthy controls. The comparable virulence of the strains suggest
it does not influence the clinical outcome. Symptomatic individuals exhibited a reduced
abundance of beneficial bacteria, presenting an opportunity for therapeutic intervention.
Therefore, we propose a probiotic mix containing these beneficial bacteria, which may have
potential in protecting against diarrhea.
Next, we also evaluated the temporal changes in individuals infected with bacterial
diarrhea, in addition to the impact of antibiotic treatment. Profiles before and after disease
resolution were comparable irrespective of antibiotic treatment, questioning the necessity
of antibiotic treatment in bacterial diarrhea.
Then, we evaluated the potential of a novel fecal microbiota transplantation (FMT)
formulation encapsulated in alginate as an alternative to the current standard-of-care frozen
oral capsules. The alginate particles displayed a comparable bacterial profile to the capsules
and maintained stability over 24 months. These microbeads offer potential for a more
convenient treatment experience and easier storage at room temperature.
Lastly, we characterized the phage profiles of rCDi patients who underwent FMT. We
assessed the preservation of phages in frozen oral capsules and observed the engraftment of
donor-derived phages after treatment, which remained stable over time. Before treatment,
patients exhibited low viral diversity, which significantly increased following FMT. We report
that FMT treatment at CHUV alters the phage composition in rCDi patients, potentially
contributing to its efficacy.
In conclusion, this thesis investigated the bacterial and phage communities in patients
and formulations associated with infectious diarrhea. These findings enhance our
understanding of the role of microbiota in infectious diarrhea and provide a foundation for
developing innovative therapeutic strategies
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
Predictors of mortality of enterococcal bacteraemia and the role of source control interventions; a retrospective cohort study
No full textPurpose To identify predictors of mortality among patients with enterococcal bacteraemia.
Methods This retrospective study was conducted at the Lausanne University Hospital, Switzerland and included adult patients with enterococcal bacteraemia from 2014 to 2023.
Results During the study period, 768 enterococcal bacteraemia episodes were included. The predominant species was Enterococcus faecalis (427 episodes; 56%). Sepsis or septic shock were present in 351 (46%) episodes. The overall 30-day mortality rate was 19% (148 episodes). The Cox multivariable regression model showed that age > 60 years (aHR: 1.75, 95% CI: 1.05–2.90), nosocomial infection (1.78, 1.19–2.65), sepsis or septic shock (3.67, 2.48–5.45), and not performing source control interventions within 48 h, in patients on or discussing of transitioning to limitations of care (5.91, 3.13–11.14) were associated with 30-day mortality. Conversely, infectious diseases (ID) consultation within 48 h (0.40, 0.28–0.57), appro¬priate antimicrobial therapy within 48 h (0.54, 0.34–0.86), and source control interventions performed within 48 h (0.22, 0.14–0.36) or not warranted (0.54; 0.34–0.86) were associated with survival. Among the 737 episodes without limitation of care, the Cox multivariable regression model showed that nosocomial infection (1.78, 1.19–2.67), sepsis or septic shock (3.76, 2.42–5.82), were associated with 30-day mortality. Conversely, ID consultation within 48 h (0.44, 0.30–0.65), appro¬priate antimicrobial therapy within 48 h (0.51, 0.30–0.86), and source control interventions performed within 48 h (0.25, 0.16–0.40) or not warranted (0.40; 0.26–0.61) were associated with survival.
Conclusions Our findings underscore the pivotal role of early management of enterococcal bacteraemia, including ID con¬sultation, appropriate antimicrobial treatment initiation and performance of source control interventions
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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