Portail HAL de l'Université Picardie Jules Verne
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DADM2D-SFL: Decentralised Aggregation framework based on DBSCAN Malicious Model Detection for Secure Federated Learning
No full textInternational audienceFederated Learning (FL) is susceptible to adversarial attacks, such as Label Flipping (LF) and Backdoor, where malicious clients manipulate the updates of their local model to reduce the global model's performance. Traditional FL relies on a centralised aggregator, which must be trusted, creating a single point of failure. This centralization not only increases computational cost but also introduces scalability challenges. To address these issues, we propose a Blockchain (BC) based FL framework that decentralises the aggregation process and incorporates an enhanced Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method to identify and remove malicious updates without ignoring minor groups. Our approach eliminates the need for a centralised aggregator by leveraging BC's smart contracts to aggregate the global model. Simultaneously, Enhanced DBSCAN identifies malicious updates in the parameter space, effectively mitigating adversarial influence while preserving privacy. We evaluate both of our framework and the traditional FL under LF redand Backdoor attacks, experimental results demonstrate that our approach outperforms the traditional FL according to multiple metrics, including accuracy, loss, precision, recall, and F1-score. These findings emphasise the effectiveness of our BC-based decentralised aggregation combined with enhanced DBSCAN technique in improving the robustness and security of FL systems
DOP029 One-Year Effectiveness and Safety of Upadacitinib in 261 Patients With Crohn’s Disease: A Multicenter Real-World Cohort Study
No full textDigital Oral PresentationInternational audienc
Open Approach of Ascending Aorta Septic Rupture
No full textInternational audienceBackgroundSeptic pseudoaneurysms of the native ascending aorta are rare and challenging to treat, especially in elderly, comorbid patients with septic conditions and unfavorable anatomy for endovascular repair.Case SummaryA 78-year-old man with prior tricuspid valve replacement for endocarditis presented with methicillin-sensitive Staphylococcus aureus bacteremia. Imaging showed a large ascending aorta pseudoaneurysm, likely at the previous cardioplegia site. He underwent successful surgical repair via direct bovine pericardial patch closure under normothermic cardiopulmonary bypass. Recovery was uneventful.DiscussionEndovascular repair requires suitable anatomy, including adequate landing zones and small neck size, which were lacking here. Direct surgical patch repair offers a safe, effective, and less-invasive alternative to full aortic replacement, especially in septic, frail patients.Take-Home MessagesMultidisciplinary heart team discussion is essential to tailor management for complex septic aortic pseudoaneurysms. When endovascular treatment is unfeasible, direct surgical patch repair remains a safe and effective option in selected patients
Otitis medias agudas
No full textInternational audienceLa otitis media aguda (OMA) es una inflamación del oído medio, principalmente de origen infeccioso. Es una de las razones principales de prescripción de antibióticos en niños. Se trata de una de las infecciones bacterianas más comunes. Suele ser secundaria a una infección vírica de las vías respiratorias superiores asociada a una disfunción del tubo auditivo (trompa de Eustaquio). Se diagnostica por la presencia de un derrame retrotimpánico (purulento) en la otoscopia, asociado a signos inflamatorios agudos locales y generales. La combinación de otalgia (generalmente unilateral) y fiebre es altamente sugestiva de OMA. Haemophilus influenzae y Streptococcus pneumoniae son las dos principales bacterias causantes de la OMA. La conducta terapéutica se basa principalmente en el tratamiento analgésico y antibiótico, que es objeto de frecuentes recomendaciones de buenas prácticas (sociedades científicas, Alta Autoridad de Salud [HAS] francesa), debido a los numerosos parámetros que intervienen, como la edad de aparición, la tolerabilidad de la infección, la presencia o ausencia de complicaciones y el perfil cambiante de resistencia a los antibióticos de S. pneumoniae y H. influenzae
Premature Ventricular Contractions in Diabetic Patients: What Can We Learn from Cardiac Magnetic Resonance?
No full textInternational audienceBackground: We have previously showed, within a non-selected cohort of patients referred for premature ventricular contractions (PVCs) that cardiac magnetic resonance (CMR) detects structural abnormalities in 48% of cases with diabetes identified as a predictor of such abnormalities (1). This study aims to further investigate the diagnostic value of CMR specifically in diabetic patients.Methods: The study compared 25 diabetic patients (Group 1) with 175 non-diabetic patients (Group 2), all referred by cardiologists following an initial evaluation that included ECG, echocardiography and treadmill exercise ECG testing. CMR imaging was performed using 1.5 and 3 Tesla scanner with a standardized protocol. The performance of CMR was assessed based on its ability to identify structural abnormalities not previously detected during the initial workup.Results: Group 1 patients were significantly older, exhibited a higher prevalence of cardiovascular risk factor, a greater frequency of PVCs that increase with exercise as well as non-sustained ventricular tachycardia (VT) compared to Group 2 (Table1).CMR revealed a significant higher incidence of structural abnormalities in Group 1 (21 patients (84%) vs 71 patients (41%) p < 0.001) primarily characterized by non-ischemic fibrosis (48% vs 23%) followed by ischemic fibrosis (16% vs 7.4%) and mixed fibrosis (12% vs 1.1%). Wall motion abnormalities were also more prevalent in Group 1 (36% vs 10%, p=0.002). After adjusting for cardiovascular risk factors using a propensity score, multivariate analysis confirmed that diabetes is significantly and independently associated to CMR-detected structural abnormalities (OR 2.04 95% CI 1.18-3.57 p = 0.011) alongside PVCs that increase with exercise, pleomorphic PVCs and non-sustained VT (Table2).Conclusion: This preliminary study underscores the critical role of CMR in diabetic patients presenting with PVCs, revealing structural abnormalities in a substantial majority (84%), primarily non-ischemic fibrosis despite the presence of traditional cardiovascular risk factor. These findings suggest that diabetes may contribute to the development of myocardial fibrosis and could be strongly considered in diabetic patients with PVCs. Larger-scale studies are warranted to further elucidate these associations and optimize clinical management strategies
Alcohol induces sorafenib resistance in hepatocellular carcinoma: A translational study
No full textInternational audienceAlcohol is a major cause of hepatocellular carcinoma (HCC), accounting for 30% of cases worldwide. Sorafenib, a tyrosine kinase inhibitor (TKI), was the standard first-line treatment for advanced HCC until 2021, but sorafenib resistance is common. We explored the impact of chronic alcohol exposure (CAE) on sorafenib response and sought to identify associated resistance mechanisms. Huh-7 HCC cells were chronically exposed to alcohol for 6 months. Sorafenib resistance was assessed by measuring cell viability (IC50) and by evaluating the protein expression of signaling pathways involved in resistance using immunoblotting. RNA sequencing was performed to identify mechanisms of resistance. Sorafenib response was assessed using the RECIST 1.1 criteria in HCC patients. A retrospective study of 86 HCC patients from the CHIEF cohort (alcohol-related vs. non-alcohol-related etiologies) evaluated overall survival (OS) and progression-free survival (PFS) using the log-rank test. CAE significantly decreased cell sensitivity to sorafenib (p = 0.006), indicating increased resistance. The ERK pathway was involved. RNA sequencing of our cells identified a total of 80 differentially expressed genes associated with drug resistance and aggressiveness. Clinically, alcohol-related HCC patients were less responsive to sorafenib (35% responders vs. 65%, p = 0.014) and had significantly different OS (p = 0.0234). Median OS was 10 months (95% CI = [6.1, 15.7]) for alcohol-related HCC and 12.1 months (95% CI = [7.7, 64.9]) for other etiologies. PFS was lower in the alcohol group (5.72 months (95% CI = [4.63, 12.8]) vs. 9.66 months (95% CI = [4.40, 39.9], p = 0.0298). Sorafenib resistance due to chronic alcohol consumption is consistent in both in vitro models and clinical settings. KEY MESSAGES: Chronic alcohol exposure reduces the effectiveness of sorafenib in hepatocellular carcinoma (HCC), as demonstrated in both in vitro and clinical settings. In vitro, alcohol-exposed HCC cells showed increased sorafenib resistance, associated with activation of the ERK signaling pathway and differential expression of 80 genes linked to drug resistance and tumor aggressiveness. Clinically, patients with alcohol-related HCC had poorer responses to sorafenib and shorter overall and progression-free survival compared to patients with non-alcohol-related HCC. These findings suggest that alcohol-related HCC may require alternative or personalized therapeutic strategies beyond standard TKI treatments
Barthélémy Toguo, Stronger together : catalogue d’exposition, musée d’art moderne et contemporain Mohammed VI, Rabat, Maroc, 2024
No full textInternational audienceArtiste camerounais de renommée mondiale, Barthélémy Toguo est reconnu pour son art universel et sa démarche artistique particulière. Au-delà de sa dimension provocatrice, son travail revêt une portée politique ainsi qu’une profonde réflexion sur la condition humaine, en particulier celle des migrants. À travers ses installations, il aborde la complexité de s’intégrer dans une nouvelle culture tout en préservant ses racines, soulignant les défis et les questionnements inhérents à ce processus
: Suivi qualitatif du recours au Contrat d’engagement jeune
No full textLe Contrat d’engagement jeune (CEJ), initié en mars 2022, s’adresse aux jeunes de 16 à 25 ans en difficulté d’insertion sociale et professionnelle. Mis en œuvre par les Missions locales et par France Travail, il combine un accompagnement « intensif » par une conseillère et une allocation mensuelle, conditionnés à la réalisation de 15 à 20 heures d’activités hebdomadaires. Il a fait l’objet d’une enquête sociologique, dont les résultats et analyses font l’objet de ce rapport, menée entre octobre 2023 et mai 2025. Elle repose sur 223 entretiens et 74 séquences d’observation dans onze territoires aux caractéristiques variées. Elle explore les usages du CEJ, le travail des conseillères, et les effets du dispositif sur les structures du service public de l’emploi.Succédant à la Garantie jeunes dans un contexte post-Covid marqué par une précarité juvénile et des débats sur l’ouverture du RSA aux moins de 25 ans, le CEJ est présenté comme plus « intensif » que les dispositifs lui préexistant. Il introduit une obligation inédite de « 15 à 20 heures d’activités » hebdomadaires, censée responsabiliser les jeunes et répondre aux critiques d’« assistanat ». Il est mis en œuvre par les Missions locales et France Travail. Son déploiement contribue aussi à réorganiser les politiques d’insertion : les Missions locales, historiquement en charge de ce public, l’ont perçu comme une mise en concurrence avec France Travail.Le CEJ a accéléré des transformations déjà engagées dans les Missions locales : intensification des tâches administratives, montée en puissance du management, rationalisation et division horizontale du travail. Les conseillères, majoritairement des femmes issues des classes populaires ou moyennes, revendiquent une « fibre sociale », et investissent l’écoute et le soutien relationnel dans leur relation avec les jeunes. Elles valorisent le lien de confiance qu’elles nouent avec eux et elles, et dénoncent la surcharge administrative et parfois les tensions liées au contrôle des activités. Elles jugent le CEJ de manière ambivalente en ce que d’une part, il permet de renforcer le travail relationnel, en raison de l’intensité des rencontres qu’il suppose et de sa logique contractuelle, mais que d’autre part, il génère une surcharge de travail administrative décrite comme un facteur majeur d’empêchement du travail.Les bénéficiaires du CEJ sont majoritairement issu·es des classes populaires précarisées, cumulant souvent instabilité économique, sociale, scolaire et psychique. Ils décrivent un rapport à l’école et au marché du travail marqué par des orientations subies, des emplois précaires et des expériences dévalorisantes. Au regard de leurs conditions de vie et de leurs projets, le CEJ est un soutien important, traduit par une aide financière et l’accompagnement d’une conseillère, mais il reste temporaire et apporte rarement une réponse structurelle à leurs difficultés.Enfin, le CEJ poursuit une logique d’adaptation des jeunes aux opportunités locales de travail ou de formation. L’exigence des « 15 à 20 heures d’activités » est son innovation majeure, mais son interprétation varie selon les territoires et les conseillères, alimentant des jugements normatifs sur la légitimité des activités. L’allocation, à la fois ressource vitale et objet de contrôle moral, cristallise les tensions entre aide sociale et contrepartie. Le CEJ semble ainsi illustrer une tendance au renforcement du contrôle et de la responsabilisation, déséquilibrant le principe des droits et devoirs dans les politiques d’insertion
Radio-anatomopathological discrepancies in lymphonodal staging of squamous cell carcinoma of the upper aerodigestive tract
No full textInternational audienceObjectives: The therapeutic strategy for squamous cell carcinomas of the upper aerodigestive tract (SCC-UADT) relies, in part, on the histopathological study of the neck dissection. Currently, several studies aim to limit the use of lymph node neck dissection based on a radioclinical cTNM evaluation. The objective of this study was therefore to assess the accuracy of clinical and radiological examination in nodal analysis of SCC-UADT compared with the histopathological assessment of neck dissection, in order to evaluate the risk of inadequate oncological management in the absence of decision-making based on the histopathological gold standard.Methods: A retrospective single-centre study was carried out between 2010 and 2024, including patients who had undergone excision and neck dissection for a primary SCC-UADT. The primary endpoint was the number of cases in which cN and pN differed during lymph node assessment of SCC-UADT. In addition, the number of lymph node metastases in level IIB in patients classified as cTXN0, as well as the number of metastases bypassing the theoretical first lymphatic drainage level in patients classified as cT1/T2N0, were collected.Results: A total of 1167 patients were identified. 457 patients (164 women and 293 men) with a mean age of 58.3 years were included. 194 patients showed a discrepancy between cN (clinical-radiological CT scan examination) and pN. 41 patients classified as cTxN0 presented a metastasis in level IIB. 16 patients classified as cT1/T2N0 had an occult metastasis bypassing the theoretical first lymph node drainage level.Conclusions: Clinical and radiological examination is not yet sufficiently reliable to serve as the sole basis for an oncological strategy concerning SCC-UADT. It is therefore necessary to pursue further investigations into the safety and reliability of therapeutic de-escalation measures.Contribution to the literature: Although there is currently a desire to place imaging at the centre of oncological strategy, this publication highlights the limitations of such an approach and the importance of histopathological assessment in the management of lymph node metastases in squamous cell carcinomas of the upper aerodigestive tract
