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Persisting thrombomodulin resistance at 3 months after liver transplantation in children with cirrhosis
Get PDFBACKGROUND: The coagulation cascade in pediatric cirrhotic patients appears rebalanced, similar to adults, with few true hemostasis-related bleeds or thromboembolic events before liver transplantation. Vascular thrombosis is an important post-liver transplantation complication. Few papers have addressed the recovery of the coagulation cascade after liver transplantation.OBJECTIVES: We aimed to assess the coagulation cascade, with both measurement of individual factors and a global hemostasis assay, before living donor liver transplantation and to investigate its recovery 3 months after transplantation, when liver function has normalized.METHODS: From January 2022 to July 2023, pediatric cirrhotic patients were prospectively enrolled 1 day before liver transplantation. An age-matched control group was included for comparison. Routine hemostasis tests, levels of coagulation factors and natural anticoagulants, and thrombomodulin-modified thrombin generation were determined on automated coagulation analyzers at inclusion and 3 months after liver transplantation.RESULTS: Twenty-seven pediatric patients with cirrhosis, primarily of cholestatic origin, and 10 controls were enrolled. Sixteen patients were sampled 3 months after liver transplantation. Pediatric end-stage liver disease scores ranged from -10 to 44. A rebalanced coagulation cascade was confirmed in cirrhotic children, indicated by a thrombomodulin-modified thrombin generation assay similar to controls, although with higher interpatient variability. Interestingly, 3 months posttransplant, coagulation was not completely normalized. In the majority of patients resistance to thrombomodulin persisted.CONCLUSION: This study confirmed a rebalanced coagulation system in pediatric cirrhotic patients before liver transplantation. Three months posttransplant thrombomodulin resistance persisted. Whereas this contributes to thrombotic complications observed after liver transplantation, remains to be elucidated.</p
Crise et désengagements politiques dans la littérature triumvirale. Analyse croisée des préfaces de Salluste, de la 'Vie d’Atticus' de Cornelius Nepos et des 'Épodes' d’Horace
No full textLes écrivains de la période triumvirale (tant les auteurs en prose de "l’époque cicéronienne" que la première génération des poètes "augustéens") ont tous formulé, d’une manière ou d’une autre, le constat douloureux de la crise dans laquelle était alors plongée Rome. Cette contribution porte sur quelques textes de cette littérature triumvirale : les préfaces des deux monographies de Salluste, la 'Vie d’Atticus' de Cornelius Nepos et les 'Épodes' d’Horace. Ceux-ci sont analysés comme des sources nous documentant sur les échappatoires ou les stratégies de résilience envisagées par ces auteurs plongés dans le chaos de la vie politique de leur temps. Salluste et Cornelius Nepos prônent le désengagement politique comme réponse aux troubles de la res publica, de même que la 16e épode d’Horace (à travers l’allégorique de la fuite hors de la cité). Ce choix de vie entrait en contradiction avec l’idéologie civique traditionnelle et appelait une justification morale, que l’on trouve chez Salluste et Cornelius Nepos. Les troubles paroxystiques de la période triumvirale entraînent ainsi une reconfiguration du maillage des valeurs civiques et des normes comportementales. Dans ce contexte, la place et le rôle de l’otium dans la vie des citoyens sont réévalués. La question de l’otium traverse le recueil des Épodes d’Horace. L’otium symposiaque y apparaît comme un moment de divertissement pour tenter d’échapper aux soucis de la guerre civile. En revanche, chez Salluste et Nepos, il constitue un choix de vie permanent, et les préfaces sallustiennes revendiquent l’utilité de l’otium historiographique pour la res publica. L’otium peut alors être défini comme un lieu de résilience face à la crise
Role of a TonB-dependent receptor and an oxygenase in iron-dependent copper resistance in Caulobacter crescentus
Get PDFCopper (Cu) is potentially threatening for living organisms owing to its toxicity at high concentrations, requiring the onset of diverse detoxification strategies to maintain fitness. We previously showed that the environmental conditions modulate the response of the oligotrophic alphaproteobacterium Caulobacter crescentus to Cu excess. In the present study, we investigated the role of the Fe-importing TonB-dependent receptor (TBDR) CciT and its partner, CciO, a 2-oxoglutarate/Fe 2+-dependent oxygenase, in Cu resistance. CciT is specifically involved in Cu resistance in both rich and poor media. Using inductively coupled plasma optical emission spectrometry, we found that under Cu stress, the cellular Cu content is reduced by overexpression of cciT, while the Fe content increases. Mutations of the three known Fe-importing TBDRs reveal that CciT is the primary Fe importer in these conditions and the only TBDR required for Cu resistance. In addition, the extracellular Fe concentration is positively correlated with the cellular Fe content and negatively correlated with the cellular Cu content, resulting in the protection of the cells against Cu excess. The operon organization of cciT and cciO is highly conserved across bacteria, indicating a functional link between the two proteins. Deletion of cciT, cciO, or both genes leads to similar Cu sensitivity. Catalytic mutations in CciT and CciO also result in Cu sensitivity. While CciO is not required for Cu and Fe transport, its precise function remains unknown. Overall, this study provides new insights into the role of Fe uptake in Cu resistance, emphasizing the critical influence of environmental conditions on bacterial physiology.</p
Measuring (Sub-)National Identities in Survey Research:Lessons from Belgium
No full textThis article explores different measurements of (sub-)national identities in survey research and examines to what extent they lead to different results. Using survey data from Belgium, where there is a long-standing tradition of (sub-)national identity surveys, three types of questions are scrutinized: the "hierarchical"question (asking respondents to which of a list of given identities they feel most closely related in first and second place), the "Linz-Moreno"question (asking respondents to situate their regional and national identities vis-à-vis each other), and the more recent "metric"question (asking respondents to situate themselves on distinct eleven-point scales for multiple identities). This article analyzes the extent to which respondents answer these questions consistently, how varying degrees of consistency can be explained, and what this tells us about the way social scientists measure (sub-)national identities. The results show that, depending on the question, only 39.4 percent to 69.2 percent of the respondents answered the three (sub-)national identity questions consistently. Differences in consistency are found to be not only related to respondents' political knowledge and interest, but also to the question forms and wording, leading us to reflect on the validity of identity measurements.</p
Clathrin-independent endocytosis and retrograde transport in cancer cells promote cytotoxic CD8 T cell activation
Get PDFFast Stochastic Second-Order Adagrad for Nonconvex Bound-Constrained Optimization
Get PDFADAGB2, a generalization of the Adagrad algorithm for stochastic optimization is introduced, which is also applicable to bound-constrained problems and capable of using second-order information when available. It is shown that, given delta in (0,1) and epsilon in 0,1], the ADAGB2 algorithm needs at most O(\epsilon^{-2}) iterations to ensure an epsilon-approximate first-order critical point of the bound-constrained problem with probability at least 1-delta, provided the average root mean square error of the gradient oracle is sufficiently small. Should this condition fail, it is also shown that the optimality level of iterates is bounded above by this average.The relation between the approximate and true classical projected-gradient-based optimality measures for bound constrained problems is also investigated, and it is shown that merely assuming unbiased gradient oracles may be insufficient to ensure convergence in O(\epsilon^{-2}) iterations
Transfert des effets d’un entraînement de fonctions exécutives chez des adolescents en situation scolaire. Le cas de l’étude des nombres rationnels dans les disciplines scientifiques
No full textLes fonctions exécutives (FE) regroupent un ensemble d’aptitudes mentales d’ordre élevé qui déterminent la réussite d’un individu dans différents domaines, comme les performances académiques ou le comportement d’un individu dans un environnement éducatif (Roebers, 2017). Ces domaines intéressent particulièrement la communauté éducative, désireuse de mettre en place des dispositifs efficaces d’apprentissage alors que, notamment dans les disciplines scientifiques, les performances des apprenants sont régulièrement pointées du doigt par leurs enseignants.En outre, tant dans le monde de l’enseignement qu’en psychologie cognitive, ce transfert d’aptitudes mentales est généralement considéré comme difficile à effectuer, observer et enseigner. Même s’il existe dans de nombreux domaines, il ne se manifeste pas toujours de façon transparente. A fortiori, dès lors que les fonctions exécutives sont impliquées dans les performances scolaires, la question de l’observation des bénéfices de leur entraînement vers un autre domaine cognitif s’avère primordiale.Une approche particulièrement intéressante pour aborder les fonctions exécutives (FE) est celle de Miyake et ses collaborateurs (2000). À partir d’un modèle factoriel, ces auteurs ont extrait trois mécanismes distincts, mais interdépendants : l’inhibition, la flexibilité mentale et la mise à jour. L’inhibition – ou contrôle inhibiteur – est définie comme la capacité à inhiber une réponse dominante en faveur d’une autre réponse
Implementation of the response to synchronization in e-puck2 robots
No full textThe response to synchronization is a phenomenon observed in several firefly species, where male ensembles synchronize their rhythmic flashes by triggering a response from females which ends the courtship process. In this work, we present a robotic implementation of this phenomenon by using a team of static e-puck2 robots that integrate oscillatory dynamics to mimic the flashing rhythm of the fireflies. To this end, robots communicate with each other via infrared (IR) and follow a distributed control law. They are divided into two groups: one representing the male population with bursting dynamics and the other representing females with non-bursting behavior. Our experimental results demonstrate that response to synchronization is robust with respect to the presence of realistic features such as obstacles and information loss. These factors play a significant role in refining the original model and enhancing its applicability in real-world scenarios