Université Jean Moulin Lyon III

Echocardiography plays a key role in the assessment of infective endocarditis (IE). It is useful for the diagnosis of endocarditis, the assessment of the severity of the disease, the prediction of short- and long-term prognosis, the prediction of embolic events, and the follow-up of patients under specific antibiotic therapy. Echocardiography is also useful for the diagnosis and management of the complications of IE, helping the physician in decision-making, particularly when a surgical therapy is considered. Finally, intraoperative echocardiography must be performed in IE to help the surgeon in the assessment and management of patients with IE during surgery. The current 'recommendations for the practice of echocardiography in infective endocarditis' aims to provide both an updated summary concerning the value and limitations of echocardiography in IE, and clear and simple recommendations for the optimal use of both transthoracic and transoesophageal echocardiography in IE.

Abstract Atypical hemolytic uremic syndrome (aHUS) is a disease of complement dysregulation. In approximately 50% of patients, mutations have been described in the genes encoding the complement regulators factor H, MCP, and factor I or the activator factor B. We report here mutations in the central component of the complement cascade, C3, in association with aHUS. We describe 9 novel C3 mutations in 14 aHUS patients with a persistently low serum C3 level. We have demonstrated that 5 of these mutations are gain-of-function and 2 are inactivating. This establishes C3 as a susceptibility factor for aHUS.

Prader-Willi syndrome (PWS) is a complex neurogenetic disorder with considerable clinical variability that is thought in large part to be the result of a hypothalamic defect. PWS results from the absence of paternal expression of imprinted genes localized in the 15q11-q13 region; however, none of the characterized genes has so far been shown to be involved in the etiology of PWS. Here, we provide a detailed investigation of a mouse model deficient for NECDIN: Linked to the mutation, a neonatal lethality of variable penetrance is observed. Viable NECDIN: mutants show a reduction in both oxytocin-producing and luteinizing hormone-releasing hormone (LHRH)-producing neurons in hypothalamus. This represents the first evidence of a hypothalamic deficiency in a mouse model of PWS. NECDIN:-deficient mice also display increased skin scraping activity in the open field test and improved spatial learning and memory in the Morris water maze. The latter features are reminiscent of the skin picking and improved spatial memory that are characteristics of the PWS phenotype. These striking parallels in hypothalamic structure, emotional and cognitive-related behaviors strongly suggest that NECDIN is responsible for at least a subset of the multiple clinical manifestations of PWS.

Phylogenetic analysis of the Flavivirus genus, using either partial sequences of the non-structural 5 gene or the structural envelope gene, revealed an extensive series of clades defined by their epidemiology and disease associations. These phylogenies identified mosquito-borne, tick-borne and no-known-vector (NKV) virus clades, which could be further subdivided into clades defined by their principal vertebrate host. The mosquito-borne flaviviruses revealed two distinct epidemiological groups: (i) the neurotropic viruses, often associated with encephalitic disease in humans or livestock, correlated with the Culex species vector and bird reservoirs and (ii) the non-neurotropic viruses, associated with haemorrhagic disease in humans, correlated with the Aedes species vector and primate hosts. Thus, the tree topology describing the virus-host association may reflect differences in the feeding behaviour between Aedes and Culex mosquitoes. The tick-borne viruses also formed two distinct groups: one group associated with seabirds and the other, the tick-borne encephalitis complex viruses, associated primarily with rodents. The NKV flaviviruses formed three distinct groups: one group, which was closely related to the mosquito-borne viruses, associated with bats; a second group, which was more genetically distant, also associated with bats; and a third group associated with rodents. Each epidemiological group within the phylogenies revealed distinct geographical clusters in either the Old World or the New World, which for mosquito-borne viruses may reflect an Old World origin. The correlation between epidemiology, disease correlation and biogeography begins to define the complex evolutionary relationships between the virus, vector, vertebrate host and ecological niche.

BACKGROUND: Determination of sensitivity and specificity of the in vitro contracture test (IVCT) for malignant hyperthermia (MH) susceptibility using the European MH Group (EMHG) protocol has been performed in some laboratories but only on a small sample from the combined EMHG. Thus, the purpose of the present study was to determine combined EMHG sensitivity and specificity of the test. METHODS: Results of IVCT of patients with previous fulminant MH and normal, low-risk subjects (controls) were collected from 22 centres of the EMHG. IVCT was performed according to the EMHG protocol. Patients were included in the study if the clinical crisis had a score of at least 50 points with the Clinical Grading Scale. Low-risk subjects were included provided they did not belong to a family with known MH susceptibility, they had not developed any signs of MH at previous anaesthetics, and they did not suffer from any neuromuscular disease. For inclusion of both MH patients and low-risk subjects, at least 1 muscle bundle in the IVCT should have twitches of 10 mN (1 g) or more. For evaluation of individual tests, only muscle bundles with twitch heights of 10 mN (1 g) or more were used. RESULTS: A total of 1502 probands had undergone IVCT because of a previous anaesthesia with symptoms and signs suggestive of MH. Of these, 119 had clinical scores of 50 and above. From these 119 MH-suspected patients and from 202 low-risk subjects, IVCT data were collected. Subsequently, 14 MH-suspected patients were excluded from further analysis for the following reasons: In 3 patients, the suspected MH episode could be fully explained by diseases other than MH; in 11 MHS patients, IVCT was incomplete (n = 1), data were lost (n = 3), or none of the muscle bundles fulfilled twitch criteria (n = 7). Of the remaining 105 MH-suspected patients, 89 were MHS, 10 MHEh, 5 MHEc, and one MHN. Thus, we observed a diagnostic sensitivity of the IVCT of 99.0% if the MHE group is considered susceptible (95% confidence interval 94.8-100.0%). Of the 202 low-risk subjects, 3 were MHS, 5 MHEh, 5 MHEc, and 189 MHN. This gives a specificity of the IVCT of 93.6% (95% confidence interval 89.2-96.5%). CONCLUSION: The IVCT for diagnosis of MH susceptibility in Europe has a high sensitivity and a satisfactory specificity.

Extracting neuronal spiking activity from large-scale two-photon recordings remains challenging, especially in mammals in vivo, where large noises often contaminate the signals. We propose a method, MLspike, which returns the most likely spike train underlying the measured calcium fluorescence. It relies on a physiological model including baseline fluctuations and distinct nonlinearities for synthetic and genetically encoded indicators. Model parameters can be either provided by the user or estimated from the data themselves. MLspike is computationally efficient thanks to its original discretization of probability representations; moreover, it can also return spike probabilities or samples. Benchmarked on extensive simulations and real data from seven different preparations, it outperformed state-of-the-art algorithms. Combined with the finding obtained from systematic data investigation (noise level, spiking rate and so on) that photonic noise is not necessarily the main limiting factor, our method allows spike extraction from large-scale recordings, as demonstrated on acousto-optical three-dimensional recordings of over 1,000 neurons in vivo.

The purpose of this multicenter retrospective study was to analyze the causes for failure of ACL reconstruction and the influence of meniscectomies after revision. This study was conducted over a 12-year period, from 1994 to 2005 with ten French orthopaedic centers participating. Assessment included the objective International Knee Documenting Committee (IKDC) 2000 scoring system evaluation. Two hundred and ninety-three patients were available for statistics. Untreated laxity, femoral and tibial tunnel malposition, impingement, failure of fixation were assessed, new traumatism and infection were recorded. Meniscus surgery was evaluated before, during or after primary ACL reconstruction, and then during or after revision ACL surgery. The main cause for failure of ACL reconstruction was femoral tunnel malposition in 36% of the cases. Forty-four percent of the patients with an anterior femoral tunnel as a cause for failure of the primary surgery were IKDC A after revision versus 24% if the cause of failure was not the femoral tunnel (P = 0.05). A 70% meniscectomy rate was found in revision ACL reconstruction. Comparison between patients with a total meniscectomy (n = 56) and patients with preserved menisci (n = 65) revealed a better functional result and knee stability in the non-meniscectomized group (P = 0.04). This study shows that the anterior femoral tunnel malposition is the main cause for failure in ACL reconstruction. This reason for failure should be considered as a predictive factor of good result of revision ACL reconstruction. Total meniscectomy jeopardizes functional result and knee stability at follow-up.

In spite of their effectiveness, learning environments often fail to engage users and end up under-used. Many studies show that gamification of learning environments can enhance learners' motivation to use learning environments. However, learners react differently to specific game mechanics and little is known about how to adapt gaming features to learners' profiles. In this paper, we propose a process for adapting gaming features based on a player model. This model is inspired from existing player typologies and types of gamification elements. Our approach is implemented in a learning environment with five different gaming features, and evaluated with 266 participants. The main results of this study show that, amongst the most engaged learners (i.e., learners who use the environment the longest), those with adapted gaming features spend significantly more time in the learning environment. Furthermore, learners with features that are not adapted have a higher level of amotivation. These results support the relevance of adapting gaming features to enhance learners' engagement, and provide cues on means to implement adaptation mechanisms.

The authors present a new system for variable speed using a double-fed induction machine. With a special operating mode, the apparent power of the inverter can reach only 20% of the maximum mechanical power, compared to a classical solution which needs 120%. Control laws are also studied with and without a sensor and they are particularly robust. The approach is validated by simulations and experimental results.

It has been speculated that the big-fish-little-pond effect (BFLPE; the negative impact of highly selective academic settings on academic self-concept) is a consequence of invidious social comparisons experienced in higher ability schools. However, the direct role of such comparisons for the BFLPE has not heretofore been documented. The present study comprises the first evidence that the BFLPE (a) is eliminated after controlling for students' invidious comparisons with their class and (b) coexists with the assimilative and contrastive effects of upward social comparison choices on academic self-concept. These results increase understanding of the BFLPE and offer support for integrative approaches of social comparison (selective accessibility and interpretation comparison models) in a natural setting. They also lend support for the distinction between forced and deliberate social comparisons and the usefulness of distinguishing between absolute and relative comparison-level choice in self-assessment.

PURPOSE OF REVIEW: Macrophages are the first line of defense against pathogens, and the mode of their activation will determine the success or failure of the host response to pathogen aggression. Based on limited numbers of markers, activated macrophages can be classified as classically activated (M1) macrophages that support microbicidal activity or alternatively activated (M2) macrophages that are not competent to eliminate pathogens. The development of high-throughput gene expression methods affords a reappraisal of the concept of macrophage activation in human infectious diseases. RECENT FINDINGS: By combining microarray data and conventional approaches, it is becoming clear that the M1 polarization program is associated with gastrointestinal infections (e.g. typhoid fever and Helicobacter pylori gastritis) and active tuberculosis. An M2 signature is observed in lepromatous leprosy, Whipple's disease, and localized infections (keratitis, chronic rhinosinusitis). However, these findings could not be predicted from the analysis of the M1/M2 programs of macrophages stimulated in vitro. SUMMARY: The reappraisal of macrophage polarization by high-throughput methods is critical to understanding the role of macrophage polarization in infectious diseases. Only the identification of individual profiles will support promising therapeutic approaches based on target determination.

International audience

PURPOSE: The aims of this article were to report the objective results of revision ACL reconstruction and to assess the influence of an associated lateral extra-articular tenodesis on knee stability and IKDC score. METHODS: This study focused on revision ACL reconstruction and was conducted over a 10-year period, from 1994 to 2003 with ten French orthopedic centers participating. The minimum follow-up required was 2 years. To be included, patients had to be evaluated at follow-up with the objective International Knee Documenting Committee (IKDC) scoring system. In 2006, 163 patients met the inclusion criteria. RESULTS: The objective IKDC knee score improved significantly after revision ACL reconstruction, with 72% IKDC A + B (26% A). When a lateral tenodesis was performed, 80% had a negative pivot shift, versus 63% without (P = 0.03), but there was no significant difference in the IKDC score. CONCLUSION: This study shows a significant improvement in the IKDC score after revision ACL reconstruction. The association of a lateral extra-articular tenodesis with the intra-articular graft increases knee stability after revision ACL reconstruction; however, this additional procedure does not significantly alter the IKDC score at follow-up. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

OBJECTIVES: To identify the prognostic markers of a bad outcome in a large population of 104 patients with prosthetic valve endocarditis (PVE), and to study the influence of medical versus surgical strategy on outcome in PVE and thus to identify patients for whom surgery may be beneficial. DESIGN: Multicentre study. METHODS AND RESULTS: Among 104 patients, 22 (21%) died in hospital. Factors associated with in-hospital death were severe co-morbidity (6% of survivors v 41% of those who died, p = 0.05), renal failure (28% v 45%, p = 0.05), moderate to severe regurgitation (22% v 54%, p = 0.006), staphylococcal infection (16% v 54%, p = 0.001), severe heart failure (22% v 64%, p = 0.001), and occurrence of any complication (60% v 90%, p = 0.05). By multivariate analysis, severe heart failure (odds ratio 5.5) and Staphylococcus aureus infection (odds ratio 6.1) were the only independent predictors of in-hospital death. Among 82 in-hospital survivors, 21 (26%) died during a 32 month follow up. A Cox proportional hazards model identified early PVE, co-morbidity, severe heart failure, staphylococcus infection, and new prosthetic dehiscence as independent predictors of long term mortality. Mortality was not significantly different between surgical and non-surgical patients (17% v 25%, respectively, not significant). However, both in-hospital and long term mortality were reduced by a surgical approach in high risk subgroups of patients with staphylococcal PVE and complicated PVE. CONCLUSIONS: Firstly, PVE not only carries a high in-hospital mortality risk but also is associated with high long term mortality and needs close follow up after the initial episode. Secondly, congestive heart failure, early PVE, staphylococcal infection, and complicated PVE are associated with a bad outcome. Thirdly, subgroups of patients could be identified for whom surgery is associated with a better outcome: patients with staphylococcal and complicated PVE. Early surgery is strongly recommended for these patients.

Efflux pumps protect the bacterial cell by expelling toxic compounds before they reach intracellular targets. Because this mechanism actively contributes to the resistance of a given bacterium to more than one class of antibiotics, molecules that are able to block the relevant efflux pump are of potential significance to combat drug resistance caused by efflux pumps. Different quinoline derivatives including alkoxy, alkylamino, thioalkoxy and chloroquinolines have been previously reported to make Enterobacter aerogenes resistant isolates that over express the mechanism of efflux, noticeably more susceptible to structurally unrelated antibiotics. In addition, various quinoline derivatives significantly increase the intracellular concentration of chloramphenicol as reported with other inhibitors, thereby suggesting the inhibition of the drug transport by AcrAB-TolC pump, which is fully active in the clinicaly resistant isolates investigated. Here, we discuss the respective properties of this molecular family, taking into account the recent insights into the structural data of AcrB pump.

Abstract Purpose – The purpose of this paper is to measure the impact of positive and negative same‐gender fictional role models on students' self‐efficacy and entrepreneurial intention. Design/methodology/approach – The authors conducted an experimental research on 276 French students. Structural equation modeling techniques were employed to measure role model identification, attitude toward the role model, emotional arousal, entrepreneurial self‐efficacy and entrepreneurial intention. Findings – Exposure to fictional role models favorably impacts self‐efficacy and behavioral intentions if students identify with role models, hold favorable attitudes toward the message, and experience positive emotional arousal. Successful role models reinforce role model identification and generate favorable attitudes toward the message, thus enhancing self‐efficacy and entrepreneurial intention. Unsuccessful entrepreneurial role models also favorably reinforce the relationship between self‐efficacy and entrepreneurial intention. Message framing and role models' gender exert a moderating effect on these results. Practical implications – Several implications for entrepreneurship education are discussed. The predominance of masculine models in entrepreneurship discourse should be inverted in the agenda of entrepreneurship education. The authors question the overall predominance of positive models in entrepreneurial education and more deeply explore the learning value of negative models. Originality/value – Entrepreneurial literature mainly focuses on mastery experience and positive real‐life role models as antecedents of entrepreneurial self‐efficacy. Negative role models are rarely examined as potential favorable sources of self‐efficacy beliefs, and little is known about the impact of emotional arousal, another source of self‐efficacy beliefs, as theorized by Bandura.

No matter which human group we look at, past or present, euphemism and its counterpart dysphemism are powerful forces and they are extremely important for the study of language change. They provide an emotive trigger for word addition, word loss, phonological distortion and semantic shift. Word taboo plays perpetual havoc with the methods of historical comparative linguistics, even undermining one of the cornerstones of the discipline – the arbitrary nature of the word. When it comes to taboo words, speakers behave as if there were a very real connection between the physical shape of words and their taboo sense. This is why these words are so unstable and why they are so powerful. This paper reviews the various communicative functions of euphemisms and the different linguistic strategies that are used in their creation, focusing on the linguistic creativity that surrounds the topic of ‘old age’ in Modern English (Shakespeare’s sixth and seventh ages). And since personal names form such a special case of word taboo, some consideration will also be given to the ancient and modern perspective of naming.

peer reviewed

AIMS: The clinical features, prognosis, and even definition of left ventricular non-compaction (LVNC) are still the subject of much debate. The aim of this registry was to describe the clinical, echocardiographic, and prognostic features of LVNC in France. The main endpoint was to assess clinical and echocardiographic predictors of adverse outcome, defined as death or heart transplantation. METHODS AND RESULTS: Between 2004 and 2006, 154 suspected cases of LNVC were identified from a nationwide survey in France. The diagnosis of LVNC was confirmed in 105 cases by echocardiographic evaluation in a core laboratory. Clinical and echocardiographic data for the 105 cases of LVNC are presented. Left ventricular non-compaction was first detected from heart failure symptoms in 45 patients, rhythm disorders in 12, and familial screening in 8. Left ventricular ejection fraction (LVEF) was < 30% in 46% of patients, but ≥ 50% in 16%. The latter had less symptoms of severe heart failure (11 vs. 54%, P = 0.001), but similar extension of the NC zone. During 2.33 ± 1.47 years of follow-up, several complications occurred, including severe heart failure in 33 patients, transplantation in 9, ventricular arrhythmia in 7, embolic events in 9, and death in 12. Factors associated with death or heart transplantation were NYHA 3 or 4 (HR = 6.69; P = 0.0007), high LV filling pressures (HR = 7.59; P = 0.001), LVEF (HR = 0.93; P = 0.006), and hospitalization for heart failure (HR = 13.55; P < 0.0001). CONCLUSION: In this large reported series of LVNC, we observed that: (i) Left ventricular non-compaction was detected by familial screening in asymptomatic patients in 8% of cases. (ii) Left ventricular non-compaction was frequently over-diagnosed by echocardiography. (iii) Patients identified as LVNC presented with a high risk of severe complications, transplantation or death and needed close follow-up.

Comment citer cette édition ? Exemple (Chicago Manual of Style, 17e édition, format auteur-date) : « L’antilope cataloguée est un document initial » (Briet [1951] 2024, p. 8). Référence bibliographique : Briet, Suzanne. (1951) 2024. Qu’est-ce que la documentation ? Paris : Éditions documentaires, industrielles et techniques. Édition numérique : Arthur Perret.