[Acute diarrhea: updates for primary care medicine in 2023]. / Diarrhées aiguës : nouveautés 2023 pour la médecine de premier recours.

Acute diarrheal disease is a frequent primary care reason for consultation, leading to direct and indirect health costs in high-income countries. Most patients presenting with acute diarrhea will have a favorable clinical course with just a symptomatic treatment. The challenge for the general practitioner is to identify the patients who need paraclinical exams and/or antibiotics. Molecular identification of pathogens in stool samples has developed over the past years and presents both advantages and limitations. Because of increasing microbial resistance to quinolones in Campylobacter and Shigella strains, azithromycin is now the first choice for an empiric antimicrobial therapy. This article will discuss these latest developments in the management of acute diarrhea in the primary care setting.

Les diarrhées aiguës sont un motif de consultation fréquent en médecine générale et engendrent des coûts directs et indirects importants dans les pays industrialisés. Les cas sont majoritairement bénins et évoluent de manière favorable avec un traitement symptomatique. Le défi pour le médecin généraliste est d'identifier les patient-e-s nécessitant des examens complémentaires et/ou un traitement antibiotique. Ces dernières années, les examens microbiologiques moléculaires des selles se sont développés ; ils ont des avantages, mais également des limitations. Sur le plan thérapeutique, l'azithromycine est désormais à privilégier comme antibiothérapie empirique en raison de l'accroissement du nombre de souches de Campylobacter et Shigella résistantes aux quinolones. Cet article discute ces nouveautés dans la prise en charge des diarrhées aiguës du point de vue du généraliste.

[How to prepare an oral presentation†?] / Comment se préparer à une présentation orale?

Oral presentations are an important means of transmitting knowledge. Good preparation is essential to succeed in this exercise. Some steps are necessary, such as defining the main objective, focusing on the audience, managing the time, choosing the first and last words, or anticipating the audience's questions, while using the visual aids appropriately. The purpose of this article is to lead young doctors in the process of creating an oral presentation.

Les présentations orales sont un moyen important de transmission du savoir. Une bonne préparation est essentielle pour réussir cet exercice. Certaines étapes sont nécessaires, comme définir l'objectif principal, s'intéresser à son audience, gérer le temps, choisir les premiers et derniers mots ou encore anticiper les questions du public, le tout en utilisant de manière adaptée les supports visuels. Cet article a pour objectif d'accompagner les jeunes médecins dans le processus de création d'une présentation orale.

Drug Transport across Porcine Intestine Using an Ussing Chamber System: Regional Differences and the Effect of P-Glycoprotein and CYP3A4 Activity on Drug Absorption.

Drug absorption across viable porcine intestines was investigated using an Ussing chamber system. The apparent permeability coefficients, Papp,pig, were compared to the permeability coefficients determined in humans in vivo, Peff,human. Eleven drugs from the different Biopharmaceutical Classification System (BCS) categories absorbed by passive diffusion with published Peff,human values were used to test the system. The initial experiments measured Papp,pig for each drug after application in a Krebs⁻Bicarbonate Ringer (KBR) buffer and in biorelevant media FaSSIF V2 and FeSSIF V2, mimicking fasted and fed states. Strong sigmoidal correlations were observed between Peff,human and Papp,pig. Differences in the segmental Papp,pig of antipyrine, cimetidine and metoprolol confirmed the discrimination between drug uptake in the duodenum, jejunum and ileum (and colon); the results were in good agreement with human data in vivo. The presence of the P-gp inhibitor verapamil significantly increased Papp,pig across the ileum of the P-gp substrates cimetidine and ranitidine (p < 0.05). Clotrimazole, a potent CYP3A4 inhibitor, significantly increased Papp,pig of the CYP3A4 substrates midazolam, verapamil and tamoxifen and significantly decreased the formation of their main metabolites. In conclusion, the results showed that this is a robust technique to predict passive drug permeability under fasted and fed states, to identify regional differences in drug permeability and to demonstrate the activity of P-gp and CYP3A4.

Type A aortic dissection: Are there CT signs suggestive of valvular involvement?

AIM: To identify the predictive signs of aortic valve involvement on the non-electrocardiogram (ECG)-gated admission computed tomography (CT) of patients with Type A aortic dissection (AD) according to the Stanford classification. MATERIALS AND METHODS: We retrospectively analyzed the non-ECG-gated CT examinations of patients admitted to the emergency department who underwent surgery for Type A AD over a period of 4 years. The diameter of the following structures was calculated as the mean of the smallest and largest diameters (mm) measured in two different planes: aortic annulus, sinus of Valsalva, sinotubular junction, and proximal ascending aorta. These parameters were compared against operative reports in order to determine whether they were predictive of aortic valve involvement. RESULTS: In total, 20 patients (13 men and 7 women) of a mean age of 59.5 years (29-80) were included, 55% of patients (11/20) having surgically proven valvular involvement. The mean diameters (inmm) of the aortic annulus, sinus of Valsalva, sinotubular junction and proximal ascending aorta in the group with (and without, respectively) valvular involvement was 27.7 (26.7), 44.3 (38.1), 42.6 (36.6), and 47.8 (45.9). Only the measurement of the mean diameter of the sinuses of Valsalva was significantly predictive (p=0.02) of aortic valve involvement. CONCLUSION: Our findings suggest that measuring the diameter of the sinuses of Valsalva on non-ECG-gated admission CT examinations allows for predicting aortic valve involvement in Type A AD patients.

The boss is always right: Preschoolers endorse the testimony of a dominant over that of a subordinate.

Recent research has shown that young children rely on social cues to evaluate testimony. For instance, they prefer to endorse testimony provided by a consensual group than by a single dissenter. Given that dominance is pervasive in children's social environment, it can be hypothesized that children also use dominance relations in their selection of testimony. To test this hypothesis, a dominance asymmetry was induced between two characters either by having one repeatedly win in physical contests (physical power; Experiment 1) or by having one repeatedly impose her goals on the other (decisional power; Experiment 2). In two subsequent testimony tasks, 3- to 5-year-old children significantly tended to endorse the testimony of the dominant over that of the subordinate. These results suggest that preschoolers take dominance into account when evaluating testimony. In conclusion, we discuss two potential explanations for these findings.

Visual access trumps gender in 3- and 4-year-old children's endorsement of testimony.

Several studies have investigated how preschoolers weigh social cues against epistemic cues when taking testimony into account. For instance, one study showed that 4- and 5-year-olds preferred to endorse the testimony of an informant who had the same gender as the children; by contrast, when the gender cue conflicted with an epistemic cue--past reliability--the latter trumped the former. None of the previous studies, however, has shown that 3-year-olds can prioritize an epistemic cue over a social cue. In Experiment 1, we offer the first demonstration that 3-year-olds favor testimony from a same-gender informant in the absence of other cues. In Experiments 2 and 3, an epistemic cue-visual access--was introduced. In those experiments, 3- and 4-year-olds endorsed the testimony of the informant with visual access regardless of whether it was a same-gender informant (Experiment 3) or a different-gender informant (Experiment 2). These results demonstrate that 3-year-olds are able to give more weight to an epistemic cue than to a social cue when evaluating testimony.

The influence of power and reason on young Maya children's endorsement of testimony.

Two important parenting strategies are to impose one's power and to use reasoning. The effect of these strategies on children's evaluation of testimony has received very little attention. Using the epistemic vigilance framework, we predict that when the reasoning cue is strong enough it should overcome the power cue. We test this prediction in a population for which anthropological data suggest that power is the prominent strategy while reasoning is rarely relied on in the interactions with children. In Experiment 1, 4- to 6-year-old children from a traditional Maya population are shown to endorse the testimony supported by a strong argument over that supported by a weak argument. In Experiment 2, the same participants are shown to follow the testimony of a dominant over that of a subordinate. The participants are then shown to endorse the testimony of a subordinate who provides a strong argument over that of a dominant who provides either a weak argument (Experiment 3) or no argument (Experiment 4). Thus, when the power and reasoning cues conflict, reasoning completely trumps power.

Wishful thinking in preschoolers.

The current experiment sought to demonstrate the presence of wishful thinking--when wishes influence beliefs--in young children. A sample of 77 preschoolers needed to predict, eight times in a row, which of two plastic eggs, one containing one toy and the other containing three toys, would be drawn by a blinded experimenter. On the four trials in which the children could not keep the content of the egg drawn, they were equally likely to predict that either egg would be drawn. By contrast, on the four trials in which the children got to keep the content of the egg, they were more likely to predict that the egg with three toys would be drawn. Any effort the children exerted would be the same across conditions, so that this demonstration of wishful thinking cannot be accounted for by an effort heuristic. One group of children--a subgroup of the 5-year-olds--did not engage in wishful thinking. Children from this subgroup instead used the representativeness heuristic to guide their answers. This result suggests that having an explicit representation of the outcome inhibits children from engaging in wishful thinking in the same way as explicit representations constrain the operation of motivated reasoning in adults.

Procedural Metacognition and False Belief Understanding in 3- to 5-Year-Old Children.

Some studies, so far limited in number, suggest the existence of procedural metacognition in young children, that is, the practical capacity to monitor and control one's own cognitive activity in a given task. The link between procedural metacognition and false belief understanding is currently under theoretical discussion. If data with primates seem to indicate that procedural metacognition and false belief understanding are not related, no study in developmental psychology has investigated this relation in young children. The present paper aims, first, to supplement the findings concerning young children's abilities to monitor and control their uncertainty (procedural metacognition) and, second, to explore the relation between procedural metacognition and false belief understanding. To examine this, 82 3- to 5-year-old children were presented with an opt-out task and with 3 false belief tasks. Results show that children can rely on procedural metacognition to evaluate their perceptual access to information, and that success in false belief tasks does not seem related to success in the task we used to evaluate procedural metacognition. These results are coherent with a procedural view of metacognition, and are discussed in the light of recent data from primatology and developmental psychology.

Children weigh the number of informants and perceptual uncertainty when identifying objects.

The aim of this study was to evaluate how 3- to 5-year-old children (N = 150) identify an object when they are confronted with conflicting evidence, notably when the available perceptual evidence is contradicted by the testimony of either a lone informant or a three-informant consensus. Results showed that (a) 5-year-olds were more likely than 3- or 4-year-olds to rely on the perceptual evidence, ignoring claims made by the informants; (b) the three-informant consensus had more impact than a single informant for all age groups; and (c) children were more likely to make a perception-based response if the stimulus was perceptually unambiguous rather than equivocal with respect to its identity. Moreover, when children's task was to identify equivocal stimuli, they endorsed the three-informant consensus more than the lone informant. In contrast, when they needed to identify unambiguous stimuli, the number of informants did not influence children's responses. Taken together, the results show that the tendency to resist testimony on the basis of perceptual evidence increases with age. Moreover, preschoolers monitor both the characteristics of their informants and the relative ambiguity of the perceptual stimuli when they need to weigh verbal testimony against perceptual evidence.

Four- to Six-Year-Old Children's Sensitivity to Reliability Versus Consensus in the Endorsement of Object Labels.

Recent studies have demonstrated that young children use past reliability and consensus to endorse object labels. Until now, no study has investigated how children weigh these two cues when they are in conflict. The two experiments reported here were designed to explore whether any initial preference for information provided by a consensual group would be influenced by the group's subsequent unreliability. The results show that 4- and 5-year-old children were more likely to endorse labels provided by an unreliable but consensual group than the labels provided by a reliable dissenter. Six-year-olds displayed the reverse pattern. The article concludes by discussing the methodological implications of the two experiments and the developmental trajectory regarding the way children weigh consensuality versus reliability.

Flow-Through Stream Modeling with MODFLOW and MT3D: Certainties and Limitations.

This paper aims to assess MODFLOW and MT3D capabilities for simulating the spread of contaminants from a river exhibiting an unusual relationship with an alluvial aquifer, with the groundwater head higher than the river head on one side and lower on the other (flow-through stream). A series of simulation tests is conducted using a simple hypothetical model so as to characterize and quantify these limitations. Simulation results show that the expected contaminant spread could be achieved with a specific configuration composed of two sets of parameters: (1) modeled object parameters (hydraulic groundwater gradient, hydraulic conductivity values of aquifer and streambed), and (2) modeling parameters (vertical discretization of aquifer, horizontal refinement of stream modeled with River [RIV] package). The influence of these various parameters on simulation results is investigated, and potential complications and errors are identified. Contaminant spread from stream to aquifer is not always reproduced by MT3D due to the RIV package's inability to simulate lateral exchange fluxes between stream and aquifer. This paper identifies the need for a MODFLOW streamflow package allowing lateral stream-aquifer interactions and streamflow routine calculations. Such developments could be of particular interest for modeling contaminated flow-through streams.

The medium helps the message: Early sensitivity to auditory fluency in children's endorsement of statements.

Recently, a growing number of studies have investigated the cues used by children to selectively accept testimony. In parallel, several studies with adults have shown that the fluency with which information is provided influences message evaluation: adults evaluate fluent information as more credible than dysfluent information. It is therefore plausible that the fluency of a message could also influence children's endorsement of statements. Three experiments were designed to test this hypothesis with 3- to 5-year-olds where the auditory fluency of a message was manipulated by adding different levels of noise to recorded statements. The results show that 4 and 5-year-old children, but not 3-year-olds, are more likely to endorse a fluent statement than a dysfluent one. The present study constitutes a first attempt to show that fluency, i.e., ease of processing, is recruited as a cue to guide epistemic decision in children. An interpretation of the age difference based on the way cues are processed by younger children is suggested.

Physico-chemical characterization of polymeric micelles loaded with platinum derivatives by capillary electrophoresis and related methods.

(1,2-diamino-cyclohexane)Platinum(II) ((DACH)Pt) loaded polymeric micelles of poly(ethylene glycol-b-sodium glutamate) (PEG-b-PGlu) are currently studied as a potential candidate to replace oxaliplatin in the treatment of cancers with the aim to reduce side effects like cumulative peripheral distal neurotoxicity and acute dysesthesias. As for all synthetic polymeric drug delivery systems, the characterization of the (co)polymer precursors and of the final drug delivery system (polymeric micelles) is crucial to control the repeatability of the different batches and to get correlation between physico-chemical structure and biological activity. In this work, the use of capillary electrophoresis (CE) and related methods for the characterization of (DACH)Pt-loaded polymeric micelles and their precursor (PEG-b-PGlu copolymer) has been investigated in detail. The separation and quantification of residual PGlu homopolymer in the PEG-b-PGlu sample were performed by free solution capillary zone electrophoresis mode. This mode brought also information on the PEG-b-PGlu copolymer composition and polydispersity. It also permitted to monitor the decomposition of polymeric micelles in the presence of NaCl at room temperature. Interactions between PEG-b-PGlu unimers, on one hand, and polymeric micelles or surfactants, on the other hand, were studied by using the Micellar Electrokinetic Chromatography and Frontal Analysis Capillary Electrophoresis modes. Finally, weight-average hydrodynamic radii of the loaded polymeric micelles and of the PEG-b-PGlu unimers were determined by Taylor Dispersion Analysis (an absolute size determination method that can be easily implemented on CE apparatus).

Early sensitivity to arguments: how preschoolers weight circular arguments.

Observational studies suggest that children as young as 2 years can evaluate some of the arguments people offer them. However, experimental studies of sensitivity to different arguments have not yet targeted children younger than 5 years. The current study aimed at bridging this gap by testing the ability of preschoolers (3-, 4-, and 5-year-olds) to weight arguments. To do so, it focused on a common type of fallacy-circularity-to which 5-year-olds are sensitive. The current experiment asked children-and, as a group control, adults-to choose between the contradictory opinions of two speakers. In the first task, participants of all age groups favored an opinion supported by a strong argument over an opinion supported by a circular argument. In the second task, 4- and 5-year-olds, but not 3-year-olds or adults, favored the opinion supported by a circular argument over an unsupported opinion. We suggest that the results of these tasks in 3- to 5-year-olds are best interpreted as resulting from the combination of two mechanisms: (a) basic skills of argument evaluations that process the content of arguments, allowing children as young as 3 years to favor non-circular arguments over circular arguments, and (b) a heuristic that leads older children (4- and 5-year-olds) to give some weight to circular arguments, possibly by interpreting these arguments as a cue to speaker dominance.

Emotional expression and vocabulary learning in adults and children.

A great deal of what we know about the world has not been learned via first-hand observation but thanks to others' testimony. A crucial issue is to know which kind of cues people use to evaluate information provided by others. In this context, recent studies in adults and children underline that informants' facial expressions could play an essential role. To test the importance of the other's emotions in vocabulary learning, we used two avatars expressing happiness, anger or neutral emotions when proposing different verbal labels for an unknown object. Experiment 1 revealed that adult participants were significantly more likely than chance to choose the label suggested by the avatar displaying a happy face over the label suggested by the avatar displaying an angry face. Experiment 2 extended these results by showing that both adults and children as young as 3 years old showed this effect. These data suggest that decision making concerning newly acquired information depends on informant's expressions of emotions, a finding that is consistent with the idea that behavioural intents have facial signatures that can be used to detect another's intention to cooperate.

Children's understanding of ambiguous idioms and conversational perspective-taking.

The aim of this study was to test the hypothesis that conversational perspective-taking is a determinant of unfamiliar ambiguous idiom comprehension. We investigated two types of ambiguous idiom, decomposable and nondecomposable expressions, which differ in the degree to which the literal meanings of the individual words contribute to the overall idiomatic meaning. We designed an experiment to assess the relationship between the acquisition of figurative comprehension and conversational perspective-taking. Our sample of children aged 5-7 years performed three conversational perspective-taking tasks (language acts, shared/unshared information, and conversational maxims). They then listened to decomposable and nondecomposable idiomatic expressions presented in context before performing a multiple-choice task (figurative, literal, and contextual responses). Results indicated that decomposable idiom comprehension was predicted by conversational perspective-taking scores and language skills, whereas nondecomposable idiom comprehension was predicted solely by language skills. We discuss our findings with respect to verbal and pragmatic skills.

The power of well-connected arguments: early sensitivity to the connective because.

Connectives, such as because, are routinely used by parents when addressing their children, yet we do not know to what extent children are sensitive to their use. Given children's early developing abilities to evaluate testimony and produce arguments containing connectives, it was hypothesized that young children would show an appropriate reaction to the presence of connectives. Three experiments were conducted to test this hypothesis. In each, two informants gave contradicting statements regarding the location of an object and justified their positions by using a similar argument. Only one of the informants used the connective because to link his argument to the statement. In each experiment, the 3-year-olds performed at chance in selecting choices containing the connective because, but the 4- and 5-year-olds performed above chance. Moreover, in Experiments 2 and 3, the 4-year-olds, 5-year-olds, and adults performed significantly better than the 3-year-olds. These findings show that 4-year-olds, 5-year-olds, and adults are sensitive to the presence of connectives. An interpretation of the difference in performance between the 3-year-olds and the 4- and 5-year-olds in terms of metarepresentational skills is suggested.

Social cognition is not reducible to theory of mind: when children use deontic rules to predict the behaviour of others.

The objective of this paper is to discuss whether children have a capacity for deontic reasoning that is irreducible to mentalizing. The results of two experiments point to the existence of such non-mentalistic understanding and prediction of the behaviour of others. In Study 1, young children (3- and 4-year-olds) were told different versions of classic false-belief tasks, some of which were modified by the introduction of a rule or a regularity. When the task (a standard change of location task) included a rule, the performance of 3-year-olds, who fail traditional false-belief tasks, significantly improved. In Study 2, 3-year-olds proved to be able to infer a rule from a social situation and to use it in order to predict the behaviour of a character involved in a modified version of the false-belief task. These studies suggest that rules play a central role in the social cognition of young children and that deontic reasoning might not necessarily involve mind reading.