Portail HAL de l'Université Picardie Jules Verne
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Troubles cognitifs et comportementaux après AVC cérébelleux isolé : données des cohortes GRECogVASC et IDEA3
No full textInternational audienceIntroductionLes AVC cérébelleux restent peu étudiés quant à leur impact cognitif et comportemental, malgré la reconnaissance croissante d’un syndrome cognitif et affectif d’origine cérébelleuse.ObjectifsÉvaluer la fréquence et le profil des troubles cognitifs et comportementaux après AVC cérébelleux isolé, et identifier les localisations cérébelleuses associées au déficit à partir d’analyses cliniques et IRM.MéthodesÉtude observationnelle à partir des cohortes prospectives GRECogVASC et IDEA3. Un total de 375 patients consécutifs évalués à six mois, dont 18 avec AVC cérébelleux pur et 67 cérébelleux mixtes. Batterie neuropsychologique standardisée avec calcul de scores z et d’un score cognitif global trois domaines. Évaluation comportementale par ISDC. Analyses anatomiques par segmentation lobulaire cérébelleuse automatisée et mapping lésionnel sur IRM 3 T.RésultatsLes troubles neurocognitifs légers étaient fréquents mais d’occurrence comparable entre AVC cérébelleux purs (44 %), mixtes (43 %) et extra-cérébelleux (37 %). Les performances les plus discriminantes d’un AVC cérébelleux pur étaient le score cognitif global trois domaines (fonction exécutives, rapidité, langage, AUC 0,86) et le score de réduction des activités. Le score cognitif global diminuait avec la réduction d’épaisseur des lobules postéro-latéraux, et le mapping lésionnel identifiait un foyer minimal cérébelleux postéro-latéral gauche (Figure 1).DiscussionNos résultats confirment qu’un AVC cérébelleux peut entraîner un trouble cognitif léger, souvent méconnu par le dépistage global. Paraphasies sémantiques et ralentissement cognitif peuvent évoquer une dysmétrie de la pensée par déconnexion cérébello-corticale. L’impact cognitif, en partie indépendant des modifications comportementales dominées par l’hypoactivité dépressive, impose une évaluation neuropsychologique ciblée.ConclusionLes AVC cérébelleux isolés provoquent des troubles cognitifs et comportementaux possiblement liés aux régions postéro-latérales, imposant un dépistage neuropsychologique ciblé et une prise en charge adaptée comme tout autre AVC
Évaluation du ralentissement et des fonctions exécutives dans la sclérose en plaques rémittente récurrente : étude prospective amiénoise
No full textInternational audienceIntroductionDans la sclérose en plaques récurrente-rémittente (SEP-RR) les troubles cognitifs sont fréquents, dont le ralentissement et l’atteinte des fonctions exécutives (FE), mais peu évalués en pratique.ObjectifsDécrire les FE, analyser le ralentissement, et en étudier les déterminants cliniques, radiologiques et thérapeutique.MéthodesNotre étude prospective monocentrique au CHU d’Amiens avait inclus des patients SEP-RR, âgés de 18 à 65 ans, ayant bénéficié d’un bilan neuropsychologique qui étudiait la vitesse de traitement de l’information (VTI), les FE cognitives et comportementales dont l’hypoactivité-apathie (HA). Une analyse a été réalisée pour rechercher une corrélation avec des facteurs cliniques, la stratégie thérapeutique et les facteurs radiologiques (dont une analyse par morphométrie voxels pour la perte de densité de substance grise).RésultatsNous avons inclus 50 patients, 27 % présentait un ralentissement, 26,7 % une HA. Le ralentissement, présent dès les épreuves les plus simples (tapotement digital) s’accentuait avec la complexité des tâches, et était lié à une perte de densité de substance grise corticale dans 9 clusters en région frontale et temporale (p < 0,001) (29 IRM réalisés au CHU et en ville). Les patients sous traitements de haute efficacité (THE) d’emblée étaient moins atteints d’HA (p = 0,006), mais la stratégie thérapeutique n’était pas en lien à la VTI (Figure 1) (Figure 2).DiscussionNos résultats suggèrent que le ralentissement a une origine mixte motrice et attentionnelle. Les patients sous THE d’emblée présentaient moins d’HA. Or l’HA a été décrit comme étant un facteur prédictif [1] au long terme du déclin cognitif dans la SEP. Une étude longitudinale avec l’inclusion de plus de patients est nécessaire pour étudier l’influence des THE sur la cognition.ConclusionCes résultats soulignent l’importance d’un dépistage systématique des FE et de l’atteinte cognitive dans la SEP-RR ainsi que de l’intégration de ces troubles dans la stratégie thérapeutique à l’avenir
« L’expression de l’émotion en littérature et en philosophie médiévales dans les textes et les représentations picturales ».
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Enhancing photovoltaic panel diagnosis using a fine-tuned convolutional neural network model
No full textInternational audienceThe diagnosis of photovoltaic (PV) panels using real current–voltage (I–V) characteristics is highly sensitive to operating conditions. This paper introduces an advanced methodology combining Artificial Intelligence (AI) techniques and engineering principles for diagnosing PV panels. On the AI side, we develop a deep learning-based model, specifically a convolutional neural network (CNN), optimized through hyperparameter tuning using the Self-adaptive Differential Evolution (SaDE) algorithm. This approach automatically adjusts the structure of the convolution layers and their hyperparameters to improve diagnostic accuracy. From the engineering perspective, the methodology relies on analyzing I–V curves using an explicit mathematical model to account for variations in solar irradiance and temperature. We investigate the effects of different PV module parameters on both illuminated and shaded I–V characteristics to enable a pre-diagnosis. The proposed model is applied to two distinct PV systems to evaluate its performance and adaptability. In the first PV system, the model classified various shading patterns based on several key features such as irradiance, temperature, and electrical parameters (open-circuit voltage, short-circuit current, and maximum power point), as well as derived metrics from the I–V curves, including fill factor, series resistance, and shunt resistance. This includes the ability to handle and diagnose erroneous I–V curves, thereby enhancing the reliability and efficiency of PV panel diagnostics under real-world conditions. In the second PV system, the model is trained using the complete I–V curves, utilizing all available data points for validation and testing. Unlike the first scenario, this approach does not require explicit inputs such as temperature or irradiance. Instead, the model autonomously classified the PV system states into healthy and faulty categories. This capability significantly broadens the model’s practical applicability, particularly for early fault detection and automation in operational PV systems. Itseffectiveness is further validated through a comparative study that implements and tests several classical machine learning models on the same dataset, clearly demonstrating the proposed model’s superiority
Linear conversions of nonlinear camera models for robotic vision applications
No full textInternational audienceCamera models play a crucial role in robot vision applications. Yet theirdiversity poses a challenge when working with data captured with camerascalibrated using different models. In this paper, we address this issue byintroducing a mathematical framework that enables conversion between various camera projection models. This approach allows algorithms designed fora specific model to process data from cameras calibrated with other models,eliminating the need for recalibration and enabling the reuse of pre-existingdatasets that do not provide access to calibration images.We present the general conversion method for state-of-the-art cameramodels that we derive for three new camera model conversions, covering various camera types, including fisheye and catadioptric systems. Quantitativeevaluation is conducted with respect to well-known calibration methods. Wecompare our method on image undistortion, as well as in practical applications such as SLAM, visual servoing, and visual odometry. The resultsdemonstrate that our conversion approach achieves performances comparable to calibration without the need for explicit calibration.This work contributes to a more flexible and adaptive use of cameras inrobot applications. The proposed camera model conversion framework is implemented in the open-source libPeR library, available at:https://github.com/PerceptionRobotique/libPeR_base
Beyond Total PCI Thresholds: Limitations of the Surgical Peritoneal Cancer Index in Decision-Making for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy
No full textInternational audienceThe Peritoneal Cancer Index (PCI) is widely used to quantify disease extent and guide therapeutic decisions for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) across multiple primary tumors. While PCI is a validated prognostic indicator, the use of a single total surgical PCI threshold as a determinant of eligibility for CRS-HIPEC presents significant conceptual and practical limitations. Surgical PCI calculation is subject to inter-surgeon variability, particularly at anatomical region boundaries, where lesion allocation may alter the total score sufficiently to influence treatment decisions. In addition, surgical PCI frequently overestimates disease extent compared with pathological PCI, while laparoscopic assessment may underestimate peritoneal involvement. Increasing evidence indicates that the anatomical distribution of peritoneal metastases, particularly involvement of critical regions such as the hepatoduodenal ligament, small bowel, and mesentery, is more predictive of resectability, morbidity, and oncologic outcome than aggregate PCI alone. Furthermore, the prognostic significance of PCI varies according to primary tumor biology, challenging the applicability of universal threshold values. These considerations suggest that total PCI should not be used in isolation to contraindicate CRS-HIPEC. Decision-making frameworks should instead emphasize regional disease distribution, technical resectability, and tumor-specific behavior to optimize patient selection
Combined methotrexate and short-term superpotent topical corticosteroids compared with prolonged superpotent topical corticosteroids alone in bullous pemphigoid: a multicentre, noninferiority randomised clinical trial
No full textInternational audienceBackground Superpotent topical corticosteroids (STS) are highly effective in bullous pemphigoid (BP), but prolonged use is associated with practical limitations and a risk of relapse. Objective To evaluate whether combining short-term STS with methotrexate (MTX) could maintain efficacy, reduce relapses, and preserve safety compared with prolonged STS alone. Methods In this multicentre, randomised, open-label, non-inferiority trial, adults with BP were assigned to receive either STS (clobetasol propionate) for one month plus low-dose MTX as maintenance (MTX + STS arm), or prolonged STS alone (STS arm). The primary endpoint was 9-month overall survival (OS), with a predefined non-inferiority margin of 15%. Secondary outcomes included relapse-free survival (RFS) and severe adverse events (SAE). Results Among 266 randomised patients (mean age 80.8 years), 9-month OS was 86.5% in the MTX + STS arm and 83.5% in the STS arm (p=0.498; hazard ratio [HR] 0.80, 95% CI 0.40–1.50). The lower limit of the 90% confidence interval for the difference in survival rates (−4.6%) remained within the predefined non-inferiority margin, meeting the primary endpoint. Among the 87.4% of patients who achieved disease control within 28 days, relapse occurred in 31 patients in the MTX + STS arm and 52 in the STS arm, corresponding to a 9-month RFS of 68.4% (95% CI 59.3–78.8) versus 47.4% (95% CI 37.7–59.5), respectively (p=0.042). SAE were more frequent in the MTX + STS arm than in the STS arm (mean number per patient per month 0.40 [95% CI 0.23–0.57] vs 0.19 [95% CI 0.01–0.36], p=0.005). Limitations The study was open-label, did not include a validated disease activity score and was conducted in a selected BP population managed under clinical trial conditions. Conclusion Maintenance therapy with low-dose MTX is non-inferior to prolonged STS in terms of survival and is associated with a reduced risk of relapse, at the cost of increased toxicit
Approche matheuristique pour la location de centres de soins et leurs services avec contraintes de capacité et gestion de pannes
No full textInternational audienceApproche matheuristique pour la location de centres de soins et leurs services avec contraintes de capacité et gestion de panne
pH-Dependent Microenvironmental Ionic Signaling in Pancreatic Ductal Adenocarcinoma.
No full textInternational audienceAim: Pancreatic ductal adenocarcinoma (PDAC) develops within a uniquely dynamic pH landscape shaped by substantial acid-base fluxes produced by the exocrine pancreas. Secretion of alkaline pancreatic juice, normally linked to digestion, produces intermittent acidifications of the pancreatic interstitium, which challenges epithelial and stromal cells. It was postulated that these unique pancreatic pH dynamics can facilitate PDAC initiation and progression through selection of a more aggressive phenotype emerging with PDAC driver mutations.Methods: Here, we summarize evidence that pH-regulatory transport proteins have an important role in shaping the PDAC microenvironment.Results: pH-regulatory transport proteins generate and sense their microenvironment and act as signaling hubs to regulate proliferation, migration, and metabolism, and immune evasion. In this way, transport proteins that are crucial for the normal physiology of the exocrine pancreas are misused and become coerced into playing a pro-cancer role in pancreatic tumor cells, pancreatic stellate cells, or infiltrating immune cells. Experiments with PDAC mouse models revealed a therapeutic potential of targeting pH dynamics, notably by inhibition or genetic ablation of pH-regulatory proteins. It is a consistent finding that these maneuvers have a marked impact on the tumor immune defense and the communication between cancer and immune cells.Conclusion: Collectively, we present a case for considering pH-regulating proteins as a therapeutic avenue