Epidemiological, clinical, and therapeutic characteristics of Behçet's disease: a monocentric study in Tunisia

Introduction: to describe the epidemiological, clinical, therapeutic and evolving characteristics of Behçet´s disease and identify prognostic factors. Methods: we have realized a retrospective, single-center study, conducted over a period of 26 years and including 130 patients presenting Behçet´s disease and hospitalized in an Internal Medicine Department. Results: the mean age of the Behçet´s disease at onset was 30.3 ±8.8 years and that at diagnosis was 34.6 ±9.4 years. The sex ratio (male/female) was 2.5. The mean delay of diagnosis was 53.5 months. Oral aphthosis was constant. The frequency of the manifestations was: genital aphtosis 71.5%, pseudofolliculitis 84.6%, erythema nodosum 11.5%, positive pathergy test 50%, ocular disease 36.9%, venous thrombosis 30%, arterial disease 4.6%, joint damage 30.8%, neurological disease 19.2% and digestive disease 0.8%. The male gender was significantly associated with ocular involvement (p =0.02), venous disease (p =0.01) and occurrence of relapses (p =0.01). The mean follow up was 68.5 ± 77.3 months. The poor survival prognostic factors were male gender, ocular involvement, venous disease, cardiovascular disease, a duration of follow up ≤12 months and a diagnostic delay ≤ 24 months. Conclusion: improving the prognosis of Behçet´s disease requires a shortening of the time to diagnosis, multidisciplinary collaboration, intensive treatment of functional threats, regular monitoring, and patient adherence

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Guidage et assistance aux procédures de radioembolisation dans le contexte de l'oncologie interventionnelle

La radioembolisation est une intervention mini-invasive réalisée pour traiter le cancer du foie en administrant des microsphères radioactives. Afin d'optimiser les résultats du traitement, la procédure est réalisée en deux sessions : une intervention de prétraitement, principalement réalisée pour localiser le site d'injection, évaluer la distribution et effectuer une évaluation dosimétrique, et une intervention de traitement réalisée pour injecter la dose appropriée de microsphères radioactives dans le site d'injection localisé. En raison la complexité de la vascularisation hépatique, les radiologues interventionnels manipulent soigneusement le cathéter, lors des deux interventions, sous guidage radiographique et recourent à l'injection de produit de contraste afin de visualiser les vaisseaux. Dans cette thèse, nous proposons une nouvelle stratégie de guidage qui promet une simplification et une précision de la navigation du cathéter lors des deux interventions. Le système de navigation proposé traite les images préopératoires et peropératoires pour réaliser une fusion d'images grâce à une technique de recalage rigide. Cette approche est conçue pour 1) aider l'accès au tronc cœliaque, 2) aider l'accès au site d'injection et 3) reproduire le site d'injection lors de l'intervention de traitement. Sachant que le foie subit un déplacement lié au mouvement respiratoire, nous proposons également une approche qui permet d'obtenir une superposition dynamique des vaisseaux 3D projetés sur la fluoroscopie.Radioembolization is a minimally-invasive intervention performed to treat liver cancer by administering radioactive microspheres. In order to optimize radioembolization outcomes, the procedure is carried out in two sessions: pretreatment assessment intervention, mainly performed to locate the injection site, assess microspheres distribution and perform dosimetry evaluation, and treatment intervention performed to inject the estimated proper dose of radioactive microspheres in the located injection site. Due to the hepatic vasculature complexity, interventional radiologists carefully manipulate the catheter, during the two interventions, under X-Ray image guidance and resort to contrast media injection in order to highlight vessels. In this thesis, we propose a novel guidance strategy that promises a simplification and accuracy of the catheter navigation during the pretreatment assessment, as well as during the treatment interventions. The proposed navigation system processes pre- and intraoperative images to achieve intraoperative image fusion through a rigid registration technique. This approach is designed to 1) assist the celiac trunk access, 2) assist the injection site access and 3) automatically reproduce the injection site during the proper intervention. Knowing that the liver undergoes a motion induced by the breathing, we also propose an approach that allows obtaining a dynamic overlay of the projected 3D vessels onto fluoroscopy

Guidage et assistance aux procédures de radioembolisation dans le contexte de l'oncologie interventionnelle

Radioembolization is a minimally-invasive intervention performed to treat liver cancer by administering radioactive microspheres. In order to optimize radioembolization outcomes, the procedure is carried out in two sessions: pretreatment assessment intervention, mainly performed to locate the injection site, assess microspheres distribution and perform dosimetry evaluation, and treatment intervention performed to inject the estimated proper dose of radioactive microspheres in the located injection site. Due to the hepatic vasculature complexity, interventional radiologists carefully manipulate the catheter, during the two interventions, under X-Ray image guidance and resort to contrast media injection in order to highlight vessels. In this thesis, we propose a novel guidance strategy that promises a simplification and accuracy of the catheter navigation during the pretreatment assessment, as well as during the treatment interventions. The proposed navigation system processes pre- and intraoperative images to achieve intraoperative image fusion through a rigid registration technique. This approach is designed to 1) assist the celiac trunk access, 2) assist the injection site access and 3) automatically reproduce the injection site during the proper intervention. Knowing that the liver undergoes a motion induced by the breathing, we also propose an approach that allows obtaining a dynamic overlay of the projected 3D vessels onto fluoroscopy.La radioembolisation est une intervention mini-invasive réalisée pour traiter le cancer du foie en administrant des microsphères radioactives. Afin d'optimiser les résultats du traitement, la procédure est réalisée en deux sessions : une intervention de prétraitement, principalement réalisée pour localiser le site d'injection, évaluer la distribution et effectuer une évaluation dosimétrique, et une intervention de traitement réalisée pour injecter la dose appropriée de microsphères radioactives dans le site d'injection localisé. En raison la complexité de la vascularisation hépatique, les radiologues interventionnels manipulent soigneusement le cathéter, lors des deux interventions, sous guidage radiographique et recourent à l'injection de produit de contraste afin de visualiser les vaisseaux. Dans cette thèse, nous proposons une nouvelle stratégie de guidage qui promet une simplification et une précision de la navigation du cathéter lors des deux interventions. Le système de navigation proposé traite les images préopératoires et peropératoires pour réaliser une fusion d'images grâce à une technique de recalage rigide. Cette approche est conçue pour 1) aider l'accès au tronc cœliaque, 2) aider l'accès au site d'injection et 3) reproduire le site d'injection lors de l'intervention de traitement. Sachant que le foie subit un déplacement lié au mouvement respiratoire, nous proposons également une approche qui permet d'obtenir une superposition dynamique des vaisseaux 3D projetés sur la fluoroscopie

Guidage et assistance aux procédures de radioembolisation dans le contexte de l'oncologie interventionnelle

Radioembolization is a minimally-invasive intervention performed to treat liver cancer by administering radioactive microspheres. In order to optimize radioembolization outcomes, the procedure is carried out in two sessions: pretreatment assessment intervention, mainly performed to locate the injection site, assess microspheres distribution and perform dosimetry evaluation, and treatment intervention performed to inject the estimated proper dose of radioactive microspheres in the located injection site. Due to the hepatic vasculature complexity, interventional radiologists carefully manipulate the catheter, during the two interventions, under X-Ray image guidance and resort to contrast media injection in order to highlight vessels. In this thesis, we propose a novel guidance strategy that promises a simplification and accuracy of the catheter navigation during the pretreatment assessment, as well as during the treatment interventions. The proposed navigation system processes pre- and intraoperative images to achieve intraoperative image fusion through a rigid registration technique. This approach is designed to 1) assist the celiac trunk access, 2) assist the injection site access and 3) automatically reproduce the injection site during the proper intervention. Knowing that the liver undergoes a motion induced by the breathing, we also propose an approach that allows obtaining a dynamic overlay of the projected 3D vessels onto fluoroscopy.La radioembolisation est une intervention mini-invasive réalisée pour traiter le cancer du foie en administrant des microsphères radioactives. Afin d'optimiser les résultats du traitement, la procédure est réalisée en deux sessions : une intervention de prétraitement, principalement réalisée pour localiser le site d'injection, évaluer la distribution et effectuer une évaluation dosimétrique, et une intervention de traitement réalisée pour injecter la dose appropriée de microsphères radioactives dans le site d'injection localisé. En raison la complexité de la vascularisation hépatique, les radiologues interventionnels manipulent soigneusement le cathéter, lors des deux interventions, sous guidage radiographique et recourent à l'injection de produit de contraste afin de visualiser les vaisseaux. Dans cette thèse, nous proposons une nouvelle stratégie de guidage qui promet une simplification et une précision de la navigation du cathéter lors des deux interventions. Le système de navigation proposé traite les images préopératoires et peropératoires pour réaliser une fusion d'images grâce à une technique de recalage rigide. Cette approche est conçue pour 1) aider l'accès au tronc cœliaque, 2) aider l'accès au site d'injection et 3) reproduire le site d'injection lors de l'intervention de traitement. Sachant que le foie subit un déplacement lié au mouvement respiratoire, nous proposons également une approche qui permet d'obtenir une superposition dynamique des vaisseaux 3D projetés sur la fluoroscopie

Guidage et assistance aux procédures de radioembolisation dans le contexte de l'oncologie interventionnelle

Radioembolization is a minimally-invasive intervention performed to treat liver cancer by administering radioactive microspheres. In order to optimize radioembolization outcomes, the procedure is carried out in two sessions: pretreatment assessment intervention, mainly performed to locate the injection site, assess microspheres distribution and perform dosimetry evaluation, and treatment intervention performed to inject the estimated proper dose of radioactive microspheres in the located injection site. Due to the hepatic vasculature complexity, interventional radiologists carefully manipulate the catheter, during the two interventions, under X-Ray image guidance and resort to contrast media injection in order to highlight vessels. In this thesis, we propose a novel guidance strategy that promises a simplification and accuracy of the catheter navigation during the pretreatment assessment, as well as during the treatment interventions. The proposed navigation system processes pre- and intraoperative images to achieve intraoperative image fusion through a rigid registration technique. This approach is designed to 1) assist the celiac trunk access, 2) assist the injection site access and 3) automatically reproduce the injection site during the proper intervention. Knowing that the liver undergoes a motion induced by the breathing, we also propose an approach that allows obtaining a dynamic overlay of the projected 3D vessels onto fluoroscopy.La radioembolisation est une intervention mini-invasive réalisée pour traiter le cancer du foie en administrant des microsphères radioactives. Afin d'optimiser les résultats du traitement, la procédure est réalisée en deux sessions : une intervention de prétraitement, principalement réalisée pour localiser le site d'injection, évaluer la distribution et effectuer une évaluation dosimétrique, et une intervention de traitement réalisée pour injecter la dose appropriée de microsphères radioactives dans le site d'injection localisé. En raison la complexité de la vascularisation hépatique, les radiologues interventionnels manipulent soigneusement le cathéter, lors des deux interventions, sous guidage radiographique et recourent à l'injection de produit de contraste afin de visualiser les vaisseaux. Dans cette thèse, nous proposons une nouvelle stratégie de guidage qui promet une simplification et une précision de la navigation du cathéter lors des deux interventions. Le système de navigation proposé traite les images préopératoires et peropératoires pour réaliser une fusion d'images grâce à une technique de recalage rigide. Cette approche est conçue pour 1) aider l'accès au tronc cœliaque, 2) aider l'accès au site d'injection et 3) reproduire le site d'injection lors de l'intervention de traitement. Sachant que le foie subit un déplacement lié au mouvement respiratoire, nous proposons également une approche qui permet d'obtenir une superposition dynamique des vaisseaux 3D projetés sur la fluoroscopie

Refeeding syndrome in adults with celiac crisis: a case report

Abstract Background Refeeding syndrome is a rare and life-threatening pathology with polyvisceral manifestations occurring in severely malnourished patients. It is rarely described in adults with celiac disease. Case presentation We report the case of a 28-year-old Tunisian woman followed up for celiac disease, who did not adhere to the gluten-free diet. She presented to our hospital with celiac crisis manifested by severe diarrhea, and metabolic and electrolyte disturbances. The treatment of electrolyte abnormalities, hydration, and nutritional support was marked by the occurrence on the fifth day of refeeding syndrome with psychomotor agitation followed by respiratory distress and a state of cardiogenic shock. Conclusions Refeeding syndrome is still under-recognized. It should be systematically prevented for high-risk patients. Nutritional support in patients with celiac crisis should be monitored carefully since the risk of refeeding syndrome is very high with a poor prognosis

On the state estimation for nonlinear continuous-time fuzzy systems

A large class of nonlinear systems can be represented or well approximated by Takagi-Sugeno (TS) fuzzy models, which in theory can approximate a general nonlinear system to an arbitrary degree of accuracy. The TS fuzzy model consists of a fuzzy rule base. The rule antecedents partition a given subspace of the model variables into fuzzy regions, while the consequent of each rule is usually a linear or affine model, valid locally in the corresponding region. In this paper, the observer design problem for a T-S fuzzy system subject to Lypschitz perturbation is investigated. First, an observer of Kalman type is designed to estimate the unknown system states. Then, the class of one-sided Lipschitz for a TS fuzzy system subject to a sufficient condition on the bound is studied. The challenges are discussed and some analysis oriented tools are provided. An example is given to show the applicability of the main result

Catheter navigation support for liver radioembolization guidance: feasibility of structure-driven intensity-based registration

International audiencePurpose The fusion of pre/intraoperative images may improve catheter manipulation during radioembolization (RE) interventions by adding relevant information. The objective of this work is to propose and evaluate the performance of a RE guidance strategy relying on structure-driven intensity-based registration between preoperative CTA and intraoperative X-ray images. Methods The navigation strategy is decomposed into three image fusion steps, supporting the catheter navigation from the femoral artery till reaching the injection site (IS). During the pretreatment assessment intervention, the aorta and the origins of its side branches are projected on the intraoperative 2D fluoroscopy following a 3D/2D bone-based registration process, to assist the celiac trunk access. Subsequently, a similar approach consisting in projecting the hepatic vasculature on intraoperative DSA through 3D/2D vessel-based registration is performed to assist the IS location. Lastly, the selected IS is reproduced during the treatment intervention by employing 2D/2D image-based registration between pretreatment and treatment fluoroscopic images. Results The three fusion steps were independently evaluated on subsets of 20, 19 and 5 patient cases, respectively. Best results were obtained with gradient difference as similarity measure and with a delimited preoperative vascular structure for vessel-based registration. The approach resulted in qualitatively appropriate anatomical correspondences when projecting the preoperative structures on intraoperative images. With the best configuration, the registration steps showed accuracy and feasibility in aligning data, with global mean landmarks errors of 1.59 mm, 2.32 mm and 2.17 mm, respectively, a computation time that never exceeded 5 s, 25 s and 11 s, respectively, and a user interaction limited to manual initialization of the 3D/2D registration. Conclusion An image fusion-based approach has been specifically proposed for RE procedures guidance. The catheter manipulation strategy based on the fusion of pre- and intraoperative images has the potential to support different steps of the RE clinical workflow and to guide the overall procedure