1,720,965 research outputs found
Obésité et risque cardiovasculaire : le rôle de la chirurgie bariatrique dans la modulation du microbiote intestinal
No full textCes dernières années, une attention croissante a été portée au microbiote intestinal (MI) en raison de son rôle dans les maladies métaboliques, la santé cardiovasculaire, les troubles gastro-intestinaux et les cancers. Chez les individus atteints d’obésité, une diminution de la richesse, de la diversité et de la composition du MI a souvent été observée, et cela a été associé aux traits métaboliques et à l’inflammation systémique de bas grade. Un moyen de réduire les risques cardiométaboliques est la chirurgie de l’obésité. Le nombre de chirurgies bariatriques a augmenté en parallèle avec la prévalence croissante de l’obésité sévère ces dernières années. La chirurgie métabolique, telle que le by pass gastrique Roux-en-Y (RYGB) ou la sleeve gastrectomie (SG), a en effet démontré des résultats prometteurs en termes de perte de poids à long terme, d’amélioration de l’état métabolique et même de rémission des comorbidités. Cependant, ces résultats positifs ne peuvent être attribués uniquement à la restriction de l’apport alimentaire ou à la malabsorption. Des données suggèrent que la chirurgie bariatrique entraîne des modifications significatives dans le microbiome intestinal, ce qui pourrait contribuer aux effets bénéfiques observés sur les complications liées à l’obésité. Ces changements pourraient jouer un rôle crucial dans la réduction des maladies cardiovasculaires. Par conséquent, l’objectif principal de cette revue est de mieux comprendre les liens entre la composition du MI après une chirurgie bariatrique et l’amélioration de la santé cardiovasculaire. En explorant cette relation complexe, les équipes dans le domaine espèrent éclairer les mécanismes sous-jacents et ouvrir la voie à de nouvelles stratégies thérapeutiques pour améliorer la santé cardiovasculaire chez les patients ayant subi une chirurgie bariatrique. © 2023 Société francophone nutrition clinique et métabolisme (SFNCM). Publié par Elsevier Masson SAS. Tous droits réservés. In recent years, increasing attention has been given to the gut microbiota because of its role in metabolic diseases, cardiovascular health, gastrointestinal disorders, and cancers. In individuals suffering from obesity, a reduction in the richness, diversity, and composition of the intestinal microbiota has often been observed, and this has been associated with metabolic traits and low-grade systemic inflammation. Bariatric surgery has emerged as a valuable approach for reducing cardiometabolic risk. Recently, the number of bariatric surgeries has increased in parallel with the growing prevalence of severe obesity. Metabolic surgery, such as Roux-en-Y gastric bypass or Sleeve Gastrectomy, has shown promising results in terms of long-term weight loss, improved metabolic status, and even remission of comorbidities. However, it is important to note that these positive results cannot be attributed solely to food intake restriction or malabsorption. Emerging evidence suggests that bariatric surgery leads to significant changes in the intestinal microbiome, which may contribute to the beneficial effects observed on obesity-related complications. These changes could play a crucial role in reducing cardiovascular disease. Therefore, the main objective of this review is to better understand the links between the composition of the gut microbiota after bariatric surgery and improved cardiovascular health. By exploring this complex relationship, research teams aim to shed light on the underlying mechanisms and pave the way for novel therapeutic strategies to improve cardiovascular health in patients who have undergone bariatric surgery. © 2023 Société francophone nutrition clinique et métabolisme (SFNCM). Published by Elsevier Masson SAS. All rights reserved
Nourishing the gut: the impact of diet on host–gut microbiota interaction
No full textPurpose of reviewUnderstanding the spectrum of drivers that influence the gut microbiome (GM) remains a crucial field of investigation. Among these factors, diet has received particular attention, as it could explain up to 20% of the variability in GM composition between individuals. This review focuses on the complex relationships between different dietary patterns and GM in humans, based on recent findings.Recent findingsCurrent evidence underscores the multifaceted impact of diet on GM richness, diversity, and overall composition. Key contributing factors encompass dietary habits, nutritional interventions, food quality and variety, macronutrient distribution, timing of feeding, and selective exclusion of certain foods.SummaryThe intricate interplay between diet and GM is of fundamental importance in shaping the interaction between the host and the environment. Further understanding the causal impact of diet on GM has promising potential for the advancement of strategies to promote health and mitigate cardio-metabolic disease risks through dietary interventions.Graphical abstracthttp://links.lww.com/COCN/A2
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
Gut microbiota and B vitamins in severe obesity : the biotin example
No full textL’obésité est une maladie multifactorielle, à laquelle contribuent de nombreux facteurs, dont le microbiote intestinal. L’étude des fonctions qu’il assure est un élément clé de la compréhension des interactions bactéries/hôte. Ce potentiel fonctionnel s’opère par l’intermédiaire de métabolites parmi lesquelles on trouve les vitamines du groupe B. L’analyse de données métagénomiques a permis de mettre en évidence un déficit relatif en vitamine B7/B8 (biotine) au niveau de l’hôte et du microbiote intestinal en situation d’obésité sévère. En conduisant une série d’expériences chez la souris, nous avons démontré i) la contribution du microbiote dans la production de biotine, ii) le rôle du régime gras (HFD) dans l’altération du statut en biotine du microbiote et de l’hôte et iii) l’effet d’une supplémentation en biotine combinée à un prébiotique (FOS) dans le rétablissement du métabolisme vitaminique bactérien et l’amélioration des altérations métaboliques et tissulaires induites par le HFD. Par ailleurs, nous avons cherché à faciliter l’absorption de la biotine, altérée en situation d’inflammation comme observée dans l’obésité, via une action anti-inflammatoire intestinale (5-ASA). Le 5-ASA combiné au FOS, sous HFD, n’a pas permis de rétablir le métabolisme vitaminique, mais a entrainé une limitation importante des altérations métaboliques induites par ce régime. Nos différentes interventions ont donc mis en évidence l’importance de la prise en compte du statut vitaminique des patients en situation d’obésité sévère. Ces résultats renforcent l’intérêt de l’utilisation combinaisons de traitements, ciblant différents organes et voies métaboliques, dans l’obésité sévère.Obesity is a complex multifactorial pathology with many contributing factors, including the gut microbiota. The study of its functional role is a key component of understanding bacteria/host interactions. This functional potential is notably ensured through metabolites, among which we can find B vitamins. By investigating human metagenomics data, we observed an alteration in B7/B8 vitamin (biotin) metabolism at the host and bacterial level, in severe obesity. By performing a series of murine experiments, we demonstrated i) the contribution of the gut microbiota to biotin production, ii) the impact of a high-fat diet (HFD) on the alteration of biotin status for the host and the gut microbiota and iii) the action of the supplementation of biotin combined with a prebiotic (FOS) in restoring vitamin bacterial metabolism as well as improving metabolic and tissue impairments induced by HFD. We, then, tried to facilitate intestinal biotin absorption, known to be altered in inflammatory conditions, as found in obesity, via an intestinal anti-inflammatory (5-ASA) action. The 5-ASA, combined with FOS treatment in HFD-fed mice, was not efficient at restoring vitamin metabolism. Yet, this combination allowed an important limitation of metabolic alteration induced by the diet. Thus, these different interventions pointed out two main messages. First, the importance of vitamin status consideration in severe obesity. Second, the relevance of the use of combined therapies targeting different organs and metabolic pathways to improve obesity management
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
Upper small intestine microbiome in obesity and related metabolic disorders: A new field of investigation
No full textThe study of the gut microbiome holds great promise for understanding and treating metabolic diseases, as its functions and derived metabolites can influence the metabolic status of the host. While research on the fecal microbiome has provided valuable insights, it tells us only part of the story. This limitation arises from the substantial variations in microorganism distribution throughout the gastrointestinal tract due to changes in physicochemical conditions. Thus, relying solely on the fecal microbiome may not be sufficient to draw comprehensive conclusions about metabolic diseases. The proximal part of the small intestine, particularly the jejunum, indeed, serves as the crucial site for digestion and absorption of nutrients, suggesting a potential role of its microbiome in metabolic regulation. Unfortunately, it remains relatively underexplored due to limited accessibility.This review presents current evidence regarding the relationships between the microbiome in the upper small intestine and various phenotypes, focusing on obesity and type 2 diabetes, in both humans and rodents. Research on humans is still limited with variability in the population and methods used. Accordingly, to better understand the role of the whole gut microbiome in metabolic diseases, studies exploring the human microbiome in different niches are needed
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