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International audience; Purpose: To correlate the degree of foveal hypoplasia in congenital aniridia with visual acuity, iris phenotype, and PAX6 mutations.Design: Retrospective case series.Methods: 95 consecutive patients with high quality Spectral-domain optical coherence tomography (SD-OCT) records and available genotype were included in a single referral center. Iris hypoplasia was classified as complete, presence of iris root or remnants and mild atypical aniridia. SD-OCT images were assessed to classify foveal hypoplasia as Grade 1 to 4 and to determine mean thicknesses for retinal layers. For statistical analysis one eye for each patient have been used and one member of the same family has been included (n=76 eyes).Results: Most eyes (93.5%) showed variable degree of foveal hypoplasia. PAX6-positive patients presented higher degree of foveal hypoplasia than patients negative for PAX6 (p

International audience; Statement of problem: Intraoral scanners have significantly improved over the last decade. Nevertheless, data comparing intraoral digital scans with conventional impressions are sparse.Purpose: The purpose of this systematic review and meta-analysis was to determine the impact of impression technique (digital scans versus conventional impressions) on the clinical time, patient comfort, and marginal fit of tooth-supported prostheses.Material and methods: The authors conducted a literature search based on the Population, Intervention, Comparison, and Outcome (PICO) framework in 3 databases to identify clinical trials with no language or date restrictions. The mean clinical time, patient comfort, and marginal fit values of each study were independently extracted by 2 review authors and categorized according to the scanning or impression method. The authors assessed the study-level risk of bias.Results: A total of 16 clinical studies met the inclusion criteria. The mean clinical time was statistically similar for digital scan procedures (784 ±252 seconds) and for conventional impression methods (1125 ±159 seconds) (P>.05). The digital scan techniques were more comfortable for patients than conventional impressions; the mean visual analog scale score was 67.8 ±21.7 for digital scans and 39.6 ±9.3 for conventional impressions (P.05).Conclusions: Digital scan techniques are comparable with conventional impressions in terms of clinical time and marginal fit but are more comfortable for patients than conventional impression techniques.

International audience; Incomplete Hippocampal Inversion (IHI) is an atypical anatomical pattern of the hippocampus that has been associated with several brain disorders (epilepsy, schizophrenia). IHI can be visually detected on coronal T1 weighted MRI images. IHI can be absent, partial or complete (no IHI, partial IHI, IHI). However, visual evaluation can be long and tedious, justifying the need for an automatic method. In this paper, we propose, to the best of our knowledge, the first automatic IHI detection method from T1-weighted MRI. The originality of our approach is that, instead of directly detecting IHI, we propose to predict several anatomical criteria, which each characterize a particular anatomical feature of IHI, and that can ultimately be combined for IHI detection. Such individual criteria have the advantage of providing interpretable anatomical information regarding the morphological aspect of a given hippocampus. We relied on a large population of 2,008 participants from the IMAGEN study. The approach is general and can be used with different machine learning models. In this paper, we explored two different backbone models for the prediction: a linear method (ridge regression) and a deep convolutional neural network. We demonstrated that the interpretable, anatomical based prediction was at least as good as when predicting directly the presence of IHI, while providing interpretable information to the clinician or neuroscientist. This approach may be applied to other diagnostic tasks which can be characterized radiologically by several anatomical features.

In a neuropathological series of 20 COVID-19 cases, we analyzed six cases (three biopsies and three autopsies) with multiple foci predominantly affecting the white matter as shown by MRI. The cases presented with microhemorrhages evocative of small artery diseases. This COVID-19 associated cerebral microangiopathy (CCM) was characterized by perivascular changes: arterioles were surrounded by vacuolized tissue, clustered macrophages, large axonal swellings and a crown arrangement of aquaporin-4 immunoreactivity. There was evidence of blood-brain-barrier leakage. Fibrinoid necrosis, vascular occlusion, perivascular cuffing and demyelination were absent. While no viral particle or viral RNA was found in the brain, the SARS-CoV-2 spike protein was detected in the Golgi apparatus of brain endothelial cells where it closely associated with furin, a host protease known to play a key role in virus replication. Endothelial cells in culture were not permissive to SARS-CoV-2 replication. The distribution of the spike protein in brain endothelial cells differed from that observed in pneumocytes. In the latter, the diffuse cytoplasmic labeling suggested a complete replication cycle with viral release, notably through the lysosomal pathway. In contrast, in cerebral endothelial cells the excretion cycle was blocked in the Golgi apparatus. Interruption of the excretion cycle could explain the difficulty of SARS-CoV-2 to infect endothelial cells in vitro and to produce viral RNA in the brain. Specific metabolism of the virus in brain endothelial cells could weaken the cell walls and eventually lead to the characteristic lesions of COVID-19 associated cerebral microangiopathy. Furin as a modulator of vascular permeability could provide some clues for the control of late effects of microangiopathy., Free Neuropathology, Vol. 4 (2023)

Myotonic dystrophy type I (DM1) is one the most frequent muscular dystrophies in adults. Although DM1 has long been considered mainly a muscle disorder, growing evidence suggests the involvement of peripheral nerves in the pathogenicity of DM1 raising the question of whether motoneurons (MNs) actively contribute to neuromuscular defects in DM1.By using micropatterned 96-well plates as a co-culture platform, we generated a functional neuromuscular model combining DM1 and MBNL-knock-out human induced pluripotent stem cells-derived MNs and human healthy skeletal muscle cells.This approach led to the identification of pre-synaptic defects which affect the formation or stability of the neuromuscular junction at an early developmental stage. These neuropathological defects could be reproduced by the loss of RNA-binding MBNL proteins, whose loss of function in vivo is associated with muscular defects associated with DM1. These experiments indicate that the functional defects associated with MNs can be directly attributed to MBNL family proteins. Comparative transcriptomic analyses also revealed specific neuronal-related processes regulated by these proteins that are commonly misregulated in DM1.Beyond the application to DM1, our approach to generating a robust and reliable human neuromuscular system should facilitate disease modelling studies and drug screening assays.

International audience; L’obésité est une maladie complexe dont la prévalence continue à augmenter chez les enfants et les adolescents dans de nombreuses régions du monde. La SFN et l’ECOG (European Childhood Obesity Group), avec le soutien financier d’Aprifel, ont organisé un webinaire sur les dernières avancées autour des stratégies de prise en charge de l’obésité infantile. Cette session s’est tenue en digital le 19 mai 2022. L’intégralité des conférences est disponible gratuitement sur le site de la SFN à l’adresse suivante : https://sf-nutrition.fr/workshop-de-la-sfn/. Nous en présentons ici une synthèse.

Patients with hypermobile Ehlers-Danlos syndrome commonly present with painful shoulder disorders mostly represented by a multidirectional instability and with often painless episode of atraumatic shoulder dislocation and/or subluxation. Because of the generalized soft tissue fragility, most of the surgical treatments of shoulder instability, as the Bankart repair or the Latarjet procedure becomes not effective, exposing a risk of failure. Then, capsular plication has to be considered in order to reduce the articular joint volume and to diminish the mobility of the joint. Two main benefits of this surgical procedure are that it doesn’t modify the anatomy or damage the labrum or cartilage that is healthy. The purpose of this Technical Note is to present the arthroscopic capsular plication for the treatment of patient with hypermobile Ehlers-Danlos syndrome, which is associated with a multidirectional shoulder instability., Technique Video Video 1 After a first arthroscopic exploration of the glenohumeral joint, the first plication is initiated at the inferior capsule using the passing suture technique. Plications are performed with a nonabsorbable suture threads and with the arm maintained in 30° of abduction and forward flexion with a neutral rotation. The anterior capsular tissue is then assessed with the realization of two anterior plication at 3 o’clock and 5 o’clock position. Passing the arthroscope through the anterior portal, two other posterior capsular plications are then performed passing the suture thread through the posterior portal. Intraoperative drive-through test is eventually used, and additional capsular plication can be added if needed.

International audience; Sheep are one of the many animal models used to investigate the pathophysiology of disc degeneration and the regenerative strategies for intervertebral disc (IVD) disease. To date, few studies have thoroughly explored ageing of ovine lumbar IVDs. Hence, the objective of the present study was to concomitantly assess the development of spontaneous age-related lumbar IVD degeneration in sheep using X-ray, magnetic resonance imaging (MRI) as well as histological analyses. 8 young ewes (< 48 months old) and 4 skeletally mature ewes (> 48 months old) were included. Disc height, Pfirrmann and modified Pfirrmann grades as well as T2-wsi and T2 times were assessed by X-ray and MRI. The modified Boos score was also determined using histology sections. Pfirrmann (2 to 3) and modified Pfirrmann (2 to 4) grades as well as Boos scores (7 to 13) gradually increased with ageing, while T2-weighted signal intensity (1.18 to 0.75), T2 relaxation time (114.36 to 70.65 ms) and disc height (4.1 to 3.2 mm) decreased significantly. All the imaging modalities strongly correlated with the histology (p < 0.0001). The present study described the suitability of sheep as a model of age-related IVD degeneration by correlation of histological tissue alterations with the changes observed using X-ray and MRI. Given the structural similarities with humans, the study demonstrated that sheep warrant being considered as a pertinent animal model to investigate IVD regenerative strategies without induction of degeneration.

Osteosarcoma (OS) is a rare malignant primary bone tumours characterized by a high genetic and cell composition heterogeneity. Unfortunately, despite the use of drug combinations and the recent development of immunotherapies, the overall survival has not improved in the last four decades. Due to the key role of the tumour microenvironment in the pathogenesis of OS, a better understanding of its microenvironment is mandatory to develop new therapeutic approaches. From retrospective biological cohorts of OS, we analysed by immunohistochemistry the presence of lipopolysaccharide (LPS)-binding protein (LBP) in diagnostic biopsies with local disease and compared their level of infiltration to patients suffering from metastatic status. LBP is considered as a marker of LPS exposure and can indirectly reflect the presence of Gram-negative microbiota. LBP were detected in the cytoplasm of OS cells as well as in tumour-associated macrophage. Tumour samples of patients with local disease were significantly enriched in LBP compared to tumour tissues of patients with metastatic status. Lung metastatic tissues showed similar level of LBP compared to paired primary tumours. Overall, this study strongly suggests the presence of Gram-negative bacteria in OS tissues and demonstrated their significant differential level according the metastatic status. This tumour-associated microbiome may help in the conceptualisation of new therapeutic approach to trigger efficient therapeutic responses against cancer. ispartof: JOURNAL OF BONE ONCOLOGY vol:36 ispartof: location:Netherlands status: published

Nucleic-acid aptamers are of strong interest for diagnosis and therapy. Compared with antibodies, they are smaller, stable upon variations in temperature, easy to modify, and have higher tissue-penetration abilities. However, they have been little described as detection probes in histology studies of human tissue sections. In this study, we performed fluorescence imaging with two aptamers targeting cell-surface receptors EGFR and integrin α5β1, both involved in the aggressiveness of glioblastoma. The aptamers’ cell-binding specificities were confirmed using confocal imaging. The affinities of aptamers for glioblastoma cells expressing these receptors were in the 100–300 nM range. The two aptamers were then used to detect EGFR and integrin α5β1 in human glioblastoma tissues and compared with antibody labeling. Our aptafluorescence assays proved to be able to very easily reveal, in a one-step process, not only inter-tumoral glioblastoma heterogeneity (differences observed at the population level) but also intra-tumoral heterogeneity (differences among cells within individual tumors) when aptamers with different specificities were used simultaneously in multiplexing labeling experiments. The discussion also addresses the strengths and limitations of nucleic-acid aptamers for biomarker detection in histology.

International audience

International audience; The automatic analysis of stained histological sections is becoming increasingly popular. Deep Learning is today the method of choice for the computational analysis of such data, and has shown spectacular results for large datasets for a large variety of cancer types and prediction tasks. On the other hand, many scientific questions relate to small, highly specific cohorts. Such cohorts pose serious challenges for Deep Learning, typically trained on large datasets. In this article, we propose a modification of the standard nested crossvalidation procedure for hyperparameter tuning and model selection, dedicated to the analysis of small cohorts. We also propose a new architecture for the particularly challenging question of treatment prediction, and apply this workflow to the prediction of response to neoadjuvant chemotherapy for Triple Negative Breast Cancer.

Mapping the structural connectivity of the human brain is a major scientific challenge. Describing the trajectory and connections made by the hundred billion neurons that make up the brain is a titanic and multi-scale task.The major fiber bundles have been described by classical anatomical approaches since the 20th century. These studies also revealed the existence of shorter bundles, called superficial bundles, that ensure the connectivity between neighboring anatomical regions. The small size and complex shape of these bundles set a serious challenge to their visualization, so that their description remains under discussion to this day.The first research axis of this thesis aims at pushing the limits of diffusion MRI and proposing a new ex-vivo dataset of the whole human brain, called Chenonceau, dedicated to the characterization of the fine connectivity of the brain.The dataset consists of two T2-weighted anatomical acquisitions at 100 and 150 micron resolution, as well as 175 dMRI datasets at 200 micron resolution with diffusion weighting reaching 8000 s/mm2. More than 4500 hours of acquisition, distributed across two and a half years were necessary to acquire this data.Chenonceau takes advantage of the Bruker 11.7T preclinical MRI system, equipped with both a high magnetic field and a powerful gradient tunnel (780mT/m) allowing to reach the mesoscopic resolution and a very high diffusion weighting.To reconcile the large size of the human brain with the preclinical system, a new acquisition protocol is proposed. It is based on the separation of the brain into smaller samples, which are imaged individually, then reassembled in post-processing to reconstitute the full volume.The whole process is presented, including the protocol for the cutting and the storage of the anatomical samples, the details of the MRI sequences and the description of the image processing pipeline. Special attention is dedicated to the definition of the registration step which recomposes the whole volume from the individual acquisitions.The first inferences of anatomical connectivity from this new dataset are also presented. Tractography associated with clustering techniques allow the extraction of the long and superficial bundles of Chenonceau.The second part of the thesis focused on the development of a new method for fiber tracking, based on the use of the spin glass model.The latter expresses the tractography problem as a set of fiber fragments, called spins, distributed in the sample and whose position and orientation, as well as the connections they establish, are associated with an amount of energy. The construction of the tracts results from the displacement and connection of the spins, with the aim of reaching the global minimum of energy.This thesis proposes to replace the Metropolis-Hastings method used for optimization by an agent trained in a reinforcement learning framework.This new formulation aims at improving the choice of actions, which would no longer be randomly drawn, but dictated by a strategy learned by the agent, fruit of its past interactions with similar environments.The anticipation and projection capacities of such an agent appear particularly adequate to propose the most relevant trajectory in regions where the diffusion information is ambiguous. Moreover, the possibility for the algorithm to learn through interactions allows to circumvent the difficulty of establishing datasets of ground-truth bundles., La cartographie de la connectivité anatomique du cerveau humain est un défi scientifique majeur. Décrire la trajectoire et les connexions réalisées par les cent milliards de neurones qui composent le cerveau est une tâche titanesque et multi-échelle.Les grands faisceaux ont été décrits par des approches anatomiques classiques dès le 20ème siècle. Ces travaux ont également révélé l'existence de faisceaux plus courts, appelés superficiels, qui définissent la connectivité entre les régions anatomiques voisines. La taille réduite et la forme complexe de ces faisceaux posent un sérieux défi à leur visualisation, si bien que leur description demeure à ce jour débattue.Le premier axe de recherche de cette thèse vise à repousser les limites de l'IRM de diffusion et proposer un nouveau jeu de données ex-vivo du cerveau humain entier, intitulé Chenonceau, dédié à la caractérisation de la connectivité fine du cerveau.Le jeu de données est composé de deux acquisitions anatomiques pondérées en T2 à une résolution de 100 et 150 microns, ainsi que 175 jeux de données d'IRMd à une résolution de 200 microns et une pondération s'élevant jusqu'à 8000 s/mm2. Plus de 4500 heures d'acquisitions, réparties sur deux ans et demie ont été nécessaires pour acquérir ces données.Chenonceau met à profit la puissance de l'IRM pré-clinique Bruker 11.7T, doté à la fois d'un champ magnétique élevé et d'un tunnel de gradients puissants (780mT/m) permettant d'atteindre la résolution mésoscopique et une très forte pondération en diffusion.Pour concilier la taille imposante du cerveau humain avec l'imageur pré-clinique, un nouveau protocole d'acquisition est proposé. Celui-ci repose sur la séparation du cerveau en échantillons de taille réduite, qui sont sont imagés individuellement, puis réassemblés en post-traitement pour reconstituer le volume intégral.L'ensemble de la démarche est présenté, incluant le protocole de coupe et de préservation des pièces anatomiques, le détail des séquences IRM utilisées ainsi que la description du pipeline de traitement des images. Une attention particulière est portée à la définition de l'étape de recalage qui recompose le volume entier à partir des acquisitions individuelles.Les premières inférences de la connectivité anatomique issues de ce nouveau jeu de données sont également présentées. Les techniques de tractographie et de clustering permettent d'extraire non seulement les faisceaux longs de Chenonceau, mais également les faisceaux superficiels.La seconde partie de la thèse a porté sur le développement d'une nouvelle méthode de suivi de fibres, fondée sur l'utilisation d'un modèle de verres de spins.Ce dernier exprime le problème de tractographie sous la forme d'un ensemble de fragments de fibres, appelés spin, distribués dans l'échantillon et dont la position et l'orientation, ainsi que les connexions qu'ils établissent sont associés à une quantité d'énergie. La construction des tracts résulte du déplacement et de la connexion des spins, dans le but d'atteindre le minimum global d'énergie.Cette thèse propose de remplacer la méthode de Metropolis-Hastings utilisée pour l'optimisation par un agent entraîné dans un cadre d'apprentissage par renforcement.Cette nouvelle formulation vise à améliorer le choix des actions, qui ne seraient plus tirées aléatoirement, mais dictées par une stratégie apprise par l'agent, fruit de ses interactions passées avec des environnement semblables.Les capacités d'anticipation et de projection d'un tel agent apparaissent particulièrement adéquates pour proposer la trajectoire la plus pertinente dans des régions ou l'information de diffusion est ambiguë. De même, la possibilité pour l'algorithme d'apprendre au travers d'interactions permet de contourner la difficulté d'établir des ensembles de faisceaux considérées véritables.

Background Inaccurate diagnosis of encephalitis is a major issue as immunosuppressive treatments can be deleterious in case of viral infection. The European bat lyssavirus type 1 (EBLV-1), a virus related to rabies virus, is endemic in European bats. No human case has yet been reported in Western Europe. A 59-year-old patient without specific past medical history died from encephalitis. A colony of bats lived in an outbuilding of his house. No diagnosis was made using standard procedures. Methods We used a next generation sequencing (NGS) based transcriptomic protocol to search for pathogens in autopsy samples (meninges and brain frontal lobe). Results were confirmed by polymerase chain reaction (PCR) and by antibody testing in serum. Immunochemistry was used to characterize inflammatory cells and viral antigens in brain lesions. Cells and mice were inoculated with brain extracts for virus isolation. Results The patient’s brain lesions were severe and diffuse in white and gray matter. Perivascular inflammatory infiltrates were abundant and rich in plasma cells. NGS identified European bat lyssavirus type 1a in brain, which was confirmed by PCR. A high titer of neutralizing antibodies was found in serum. No viral antigen was detected, and the virus could not be isolated by cell culture or by mouse inoculation. Conclusions The patient died from European bat lyssavirus type 1a infection. NGS was key to identifying this unexpected viral etiology in an epidemiological context that did not suggest rabies. People exposed to bats should be strongly advised to be vaccinated with rabies vaccines, which are effective against EBLV-1.

International audience; Abstract Endodontics is the branch of dentistry concerned with the morphology, physiology, and pathology of the human dental pulp and periradicular tissues. Human dental pulp is a highly dynamic tissue equipped with a network of resident immunocompetent cells that play major roles in the defense against pathogens and during tissue injury. However, the efficiency of these mechanisms during dental pulp inflammation (pulpitis) varies due to anatomical and physiological restrictions. Uncontrolled, excessive, or unresolved inflammation can lead to pulp tissue necrosis and subsequent bone infections called apical periodontitis. In most cases, pulpitis treatment consists of total pulp removal. Although this strategy has a good success rate, this treatment has some drawbacks (lack of defense mechanisms, loss of healing capacities, incomplete formation of the root in young patients). In a sizeable number of clinical situations, the decision to perform pulp extirpation and endodontic treatment is justifiable by the lack of therapeutic tools that could otherwise limit the immune/inflammatory process. In the past few decades, many studies have demonstrated that the resolution of acute inflammation is necessary to avoid the development of chronic inflammation and to promote repair or regeneration. This active process is orchestrated by Specialized Pro-resolving lipid Mediators (SPMs), including lipoxins, resolvins, protectins and maresins. Interestingly, SPMs do not have direct anti-inflammatory effects by inhibiting or directly blocking this process but can actively reduce neutrophil infiltration into inflamed tissues, enhance efferocytosis and bacterial phagocytosis by monocytes and macrophages and simultaneously inhibit inflammatory cytokine production. Experimental clinical application of SPMs has shown promising result in a wide range of inflammatory diseases, such as renal fibrosis, cerebral ischemia, marginal periodontitis, and cancer; the potential of SPMs in endodontic therapy has recently been explored. In this review, our objective was to analyze the involvement and potential use of SPMs in endodontic therapies with an emphasis on SPM delivery systems to effectively administer SPMs into the dental pulp space.

Nociceptive stimulation is predicted to uniformly inhibit motoneurone pools of painful muscles and those producing painful movements. Although reduced motoneurone discharge rate during pain provides some evidence, recent data show evidence of increased excitability of some motoneurones. These observations suggest non-uniform effects of nociception on motoneurone excitability. More direct measures are required, but this is difficult to assess as few measures enable in vivo evaluation of motoneurone excitability in humans. We investigated changes in motoneurone excitability during experimental pain using two methods in separate experiments: (i) estimation of the time-course of motoneurone afterhyperpolarization (AHP) from interval death rate analysis of interspike intervals of single motor unit discharge; and (ii) probability of early motoneurone discharge to a descending volley excited using transcranial magnetic stimulation (TMS). Tibialis anterior motor units were recorded with fine-wire electrodes before, during and after painful infusion of 5% hypertonic saline into the muscle. Activation of 17 units (16 participants) could be used for AHP analysis. Data show shortened (n = 11) and lengthened (n = 6) AHP time-course. Increased (n = 6) and decreased (n = 6) probability of early motoneurone discharge were observed in the TMS experiment. These convergent observations suggest non-uniform effects of nociceptive stimulation on motoneurone pools. This does not support the hypothesis that nociceptive input induces uniform inhibition of painful muscle. Instead, interpretation of results implies redistribution of activity between motor units, with possible benefit for unloading painful tissues. This finding supports an interpretation that differs from the generally accepted view in pain physiology regarding adaptation to motor function in pain.

International audience; Introduction: This study analyzes anatomical variations of the thoracic cage (TC) according to spinopelvic alignment, age and gender using stereoradiography in erect position.Methods: This retrospective multicentric study analyzed computed parameters collected from free-standing position bi-planar radiographs, among healthy subjects. Collected data were: age, gender, pelvic parameters (Pelvic Incidence, Pelvic Tilt (PT) and Sacral Slope), T1-T12 Kyphosis (TK), L1-S1 Lordosis (LL), curvilinear spinal length, global TC parameters (maximum thickness and width, rib cage volume, mean Spinal Penetration Index (SPI)), 1st–10th rib parameters (absolute and relative (to the corresponding vertebra) sagittal angles).Results: Totally, 256 subjects were included (140 females). Mean age was 34 (range: 8–83). Significant correlations were found between TK and TC thickness (0.3, p

International audience; Osteocytes are the most frequent bone cells connected with each other through cell processes within tiny tubular-shaped canaliculi. The so-called osteocyte lacunar-canalicular network (LCN) plays a crucial role in bone remodeling and mineral homeostasis. Given the critical nature of these functions, it is herein hypothesized that the LCN must be structurally “overengineered” to provide network resilience. This hypothesis is tested by characterizing canalicular networks in human bone at the fundamental “building-block” level of LCN formed by two adjacent osteocytes. As the hierarchical micro- and macroscale structure of bone is influenced by anatomical location, subjected loads, and growth rate, three distinct tissue types are studied. These include femur, jaw, and heterotopic ossification (HO), a rapidly forming mineralized tissue found in soft tissue compartments following severe trauma. It is found that the LCNs at the fundamental level are composed of hundreds of canalicular segments but of only few separated groups of linked canaliculi (canalicular clusters), resulting in a strongly pronounced interconnectivity. Fluid permeability simulations on intact and artificially altered LCN suggest that the function of the LCN is not only to optimize rapid and efficient access to bone mineral, but also to maintain high permeability when inevitable local interruption of canaliculi occurs.

International audience; Current treatments for osteosarcoma, combining conventional polychemotherapy and surgery, make it possible to attain a five-year survival rate of 70% in affected individuals. The presence of chemoresistance and metastases significantly shorten the patient’s lifespan, making identification of new therapeutic tools essential. Inhibiting bone resorption has been shown to be an efficient adjuvant strategy impacting the metastatic dissemination of osteosarcoma, tumor growth, and associated bone destruction. Unfortunately, over-apposition of mineralized matrix by normal and tumoral osteoblasts was associated with this inhibition. Endothelin signaling is implicated in the functional differentiation of osteoblasts, raising the question of the potential value of inhibiting it alone, or in combination with bone resorption repression. Using mouse models of osteosarcoma, the impact of macitentan, an endothelin receptor inhibitor, was evaluated regarding tumor growth, metastatic dissemination, matrix over-apposition secondary to RANKL blockade, and safety when combined with chemotherapy. The results showed that macitentan has no impact on tumor growth or sensitivity to ifosfamide, but significantly reduces tumoral osteoid tissue formation and the metastatic capacity of the osteosarcoma. To conclude, macitentan appears to be a promising therapeutic adjuvant for osteosarcoma alone or associated with bone resorption inhibitors.

National audience

International audience; Complications with bilateral sagittal split osteotomy (BSSO) can sometimes result from surgical inexperience. Our aim was to present a 3-dimensional printed mandibular model for BSSO training in a maxillofacial surgical education programme. A polymethacrylate mandibular model obtained from mandibular cone-beam computed tomographic (CT) images was designed and printed for use in training. Twenty-four residents were each asked to do a BSSO according to the Epker/Dal-Pont technique. The session was conducted as a simulation course with a final debriefing. A questionnaire before and after the test was filled in using a 10-point Likert scale to assess the participants' knowledge. The mandibular model provided a realistic way of handling the trabecular bone after cortical osteotomy, as well as in the splitting phase. Significant increases in knowledge and surgical skills were noted for all steps of the BSSO, particularly regarding the use of the piezoelectric device for osteotomy, and for management of wisdom teeth in the splitting zone (3.00 ±2.16 to 6.95 ±2.06 and 2.73 ±1.91 to 5.75 ±2.63, respectively; p1=0.0002 and p2=0.0003). We think that this is a valuable printed mandibular model for the development of surgical skills for BSSO in maxillofacial surgical residents.

International audience; Background and purpose: The rationale for performing a second brain biopsy after initial negativity is not well evaluated in the literature. This study was designed to 1) assess the efficacy of a second brain biopsy when the first biopsy was nondiagnostic, 2) identify possible factors associated with an increased diagnostic rate in the second biopsy, and 3) analyze additional morbidity induced by the second biopsy.Methods: We performed a retrospective cohort study from 2009 to 2019, during which 1,919 patients underwent a brain biopsy, including 30 who were biopsied twice (1.6%). The specific histological diagnosis rate, diagnosis-associated factors, and complication rate were assessed for the 30 twice-biopsied patients.Results: The second biopsy allowed a specific histological diagnosis in 86.7% of the patients who had initially undergone a nondiagnostic brain biopsy [odds ratio (OR)=7.5, 95% confidence interval (CI)=3.0-18.7, p

Objective: To describe the rates of healing, major amputation and mortality after 12 months in patients with a new diabetic foot ulcer (DFU) and their care in a French diabetic foot service (DFS). Method: A prospective single-centre study including patients from March 2009 to December 2010. The length of time to healing, minor amputation, major amputation and mortality rate after inclusion were analysed using the Kaplan–Meier method. Results: Some 347 patients were included (3% lost to follow-up), with a median follow-up (IQR) of 19 (12–24) months. The mean (SD) age was 65±12 years, 68% were male, and the median duration of the ulcer was 49 (19–120) days. Complications of the DFU were ischaemia (70%), infection (55%) and osteomyelitis (47%). Of the patients, 50% were inpatients in the DFS at inclusion (median duration of hospitalisation 26 (15–41) days). The rate of healing at one year was 67% (95% confidence interval (CI): 61–72); of major amputation 10% (95% CI: 7–17); of minor amputation 19% (95% CI: 14–25), and the death rate was 9% (95% CI: 7–13). Using an adjusted hazard ratio, the predictive factors of healing were perfusion and the area of the wound. The risk factors for a major amputation were active smoking and osteomyelitis. The risk factors for mortality were perfusion and age. Conclusion: This study confirms the need to treat DFUs rapidly, in a multidisciplinary DFS.

International audience; Capillary network of skeletal muscle has a crucial role in oxygen supply and is strongly associated with the phenotype and metabolic profile of muscle fibers. Abundant literature has explored capillarization of skeletal muscle in different populations and in response to different interventions. Capillary and fiber type identification techniques have considerably evolved over the last decades, but to the best of our knowledge, no validated immunohistochemical method has yet been developed to simultaneously identify capillaries (using CD31), the three different muscle fiber types, and basal lamina. Nine human muscle biopsies of vastus lateralis were stained using 5 different methods to test: the reliability of different CD31 antibodies for capillary identification, the reliability between single-section or serial-section methods, and the intra-experimenter reproducibility in visual detection of capillaries. High reliability for the different antibodies directed against capillaries was observed for capillary contacts (CC) measurements (intra-class correlations (ICC) [ICC95%] of 0.89 [0.72; 0.96] for type I fibers, 0.93 [0.81; 0.97] for type IIA fibers, 0.88 [0.71; 0.96] for type IIX fibers, 0.95 [0.86; 0.98] for all fiber types) as well as a high level of similarity between single and serial sections methods. A strong similarity in capillary analysis between the different methods was obtained for each sample measurements. Analysis of Lin's concordance correlation coefficients and Bland and Altman's graphics showed a strong intra-experimenter reproducibility. This article proposes two time- and tissue-sparing immunohistochemical methods to accurately assess a complete fiber typing (type I, IIA, and IIX) along with muscle capillarization on a single muscle section.

Objective To determine the ability of three implants to enhance the healing of osteochondral defects: (1) a biphasic construct composed of calcium phosphate (CaP) and chitosan/cellulosic polymer, (2) a titanium-polyurethane implant, and (3) an osteochondral autograft. Study design Experimental study. Animals Ten adult female sheep. Methods In five sheep, an 8-mm diameter osteochondral defect was created on the medial femoral condyle of a stifle and filled with a synthetic titanium-polyurethane implant. In five sheep, a similar defect was filled with an osteochondral autograft, and the donor site was filled with a biphasic construct combining CaP granules and a chitosan/cellulosic polymer. Sheep were monitored daily for lameness. Stifle radiographs and MRI were evaluated at 20 weeks, prior to animals being humanely killed. Surgical sites were evaluated with histology, microcomputed tomography, and scanning electron microscopy. Results Clinical outcomes were satisfactory regardless of the tested biomaterials. All implants appeared in place on imaging studies. Osteointegration of prosthetic implants varied between sites, with limited ingrowth of new bone into the titanium structure. Autografts and biphasic constructs were consistently well integrated in subchondral bone. All autografts except one contained a cartilage surface, and all biphasic constructs except one partially restored hyaline cartilage surface. Conclusion Biphasic constructs supported hyaline cartilage and subchondral bone regeneration, although restoration of the articular cartilage was incomplete. Clinical impact Biphasic constructs may provide an alternative treatment for osteochondral defects, offering a less invasive approach compared with autologous grafts and eliminating the requirement for a prosthetic implant.

Unilateral posterior vertical insufficiency (PVI) is a growth defect of the mandibular condyle that results in a facial asymmetry. Various surgical procedures can be used to elongate the hypoplastic ramus. The aim of this study was to evaluate long-term aesthetic and architectural outcomes of vertical ramus osteotomy (VRO) in patients with unilateral PVI.Patients operated on with unilateral VRO were included in this retrospective study. Aesthetic and architectural parameters were evaluated on frontal photographs as well as on frontal and lateral cephalograms preoperatively, postoperatively, at 1-year and at the end of the follow-up.A total of 48 patients were analyzed. The aesthetic assessment revealed significant correction of the chin deviation (CD) and of the lip commissural line tilt after VRO (p1 = 0.0038 and p2 = 0.0067, respectively) with stable results. The architectural analysis revealed significant improvement in the maxillary and mandibular occlusal planes, as well as the chin deviation (p 0.0001). A tendency to relapse was noted for the mandibular canting and the CD during the follow-up. VRO allowed for a mean mandibular lengthening of 8.39 mm (ranging from 2.5 to 14 mm).VRO allows for immediate restoration of the symmetry of the lower third of the face in patients with unilateral PVI. A revisional procedure may be needed due to a tendency for the chin deviation to relapse.

Background Cystinosis is a rare autosomal recessive disorder caused by intracellular cystine accumulation. Proximal tubulopathy (Fanconi syndrome) is one of the first signs, leading to end-stage renal disease between the age of 12 and 16. Other symptoms occur later and encompass endocrinopathies, distal myopathy and deterioration of the central nervous system. Treatment with cysteamine if started early can delay the progression of the disease. Little is known about the neurological impairment which occurs later. The goal of the present study was to find a possible neuroanatomical dysmorphic pattern that could help to explain the cognitive profile of cystinosis patients. We also performed a detailed review of the literature on neurocognitive complications associated with cystinosis. Methods 17 patients (mean age = 17.6 years, [5.4–33.3]) with cystinosis were included in the study. Neuropsychological assessment was performed including intelligence (Intelligence Quotient (IQ) with Wechsler’s scale), memory (Children Memory Scale and Wechsler Memory Scale), visuo-spatial (Rey’s figure test) and visuo-perceptual skills assessments. Structural brain MRI (3 T) was also performed in 16 out of 17 patients, with high resolution 3D T1-weighted, 3D FLAIR and spectroscopy sequences. Results Intellectual efficiency was normal in patients with cystinosis (mean Total IQ = 93). However the Perceptual Reasoning Index (mean = 87, [63–109]) was significantly lower than the Verbal Comprehension Index (mean = 100, [59–138], p = 0.003). Memory assessment showed no difference between visual and verbal memory. But the working memory was significantly impaired in comparison with the general memory skills (p = 0.003). Visuospatial skills assessment revealed copy and reproduction scores below the 50th percentile rank in more than 70% of the patients. Brain MRI showed cortical and sub-cortical cerebral atrophy, especially in the parieto-occipital region and FLAIR hypersignals in parietal, occipital and brain stem/cerebellum. Patients with atrophic brain had lower Total IQ scores compared to non-atrophic cystinosis patients. Conclusions Patients with cystinosis have a specific neuropsychological and neuroanatomical profile. We suggest performing a systematic neuropsychological assessment in such children aiming at considering adequate management.

International audience; Sarcomas are a large family of cancers originating in the mesenchyme. Composed of more than 100 histological subtypes, soft tissue and bone sarcomas remain clinically challenging, particularly in children and adolescents in whom sarcomas are the second most common malignant entities. Osteosarcoma is the main primary bone tumor in adolescents and young adults, and is characterized by a high propensity to induce distant metastatic foci and to become multi-drug resistant. The innate and acquired resistance of osteosarcoma can be explained by high histological heterogeneity and genetic/molecular diversity. In the last decade, the notion of cancer stem-like cells (CSCs) has emerged. This subset of cancer cells has been linked to drug resistance properties, recurrence of the disease, and finally therapeutic failure. Although CSCs remain controversial, many elements are in favor of them playing a role in the development of the drug resistance profile. The present review gives a brief overview of the most recent biological evidence of the presence of CSCs in osteosarcomas and their role in the drug resistance profile of these rare oncological entities. Their use as promising therapeutic targets will be discussed.

In mammals, breathing is an automated and regulated function, characterized by a rhythmic anduninterrupted activity of the respiratory system. It is responsible for the hematosis regulation during lifetime.Respiration and its central regulation originate within the brainstem and are highly preserved function amongmammals' evolution. The retrotrapezoid nucleus (RTN), in the brainstem, is a key structure of centralchemoregulation. Mandatory for the development of the RTN, mutations of the transcription factor PHOX2B causecongenital central hypoventilation syndrome (or Ondine's syndrome). The association of PHOX2B with othermarkers (such as VGluT2, NK1R, pre pro galanin, GPR4, etc…) defines a molecular identity card which can be usedin neurohistology to identify RTN chemosensitive neurons. Recent research has suggested a RTN dysfunction relatedto respiratory disorders in neurodegenerative diseases such as Parkinson's. To date, there is no description of this keyneural structure in adult humans.The first aim of this thesis was to propose a cell-scale anatomic description of chemosensitive neurons of the humanRTN. The second objective was to set the bases for the 3D reconstruction of histologic serial sections of the humanbrainstem, along with an automated detection algorithm for specific histologic staining. The overall goal to achievewould be to allow the visualization of anatomo-functional structures within a whole reconstructed organ, from postmortem histologic sections.Based on the hypothesis of a higly preserved respiratory neural regulation among mammals, we built a comparativeneuro anatomy approach to achieve our main goal. Preserved function presuppose preserved molecular signature,hence we first described the RTN in adult non-human primates with the same markers as previous descriptions inrodents. This intermediate description in M. fascicularis confirmed us the location of the region of interest as theparafacial region, to look for in humans. We therefore identified neurons co-expressing the pre pro galanin andVGluT2 in this region of interest in the human brainstem.Our study in non-human primates allowed to improve detection algorithm of specific in situ hybridization andimmunohistochemistry which could be used for 3D reconstruction of histologic serial sections. We set themethodological bases for the development of a 3D anatomy of respiratory neural centers in human. Such methods inroutine use open the field for translational approaches combining cell, La respiration est une fonction automatique et régulée chez l'ensemble des mammifères, caractérisée par l'activité rythmique ininterrompue de l'appareil respiratoire musculo-squelettique. Elle assure de manière adaptée l'hématose, de la naissance à la mort de l'individu. Le tronc cérébral est le siège de cette fonction et de sa régulation. Elles sont extrêmement préservées au cours de l'évolution. Au sein du tronc cérébral, le noyau rétrotrapézoïde (RTN) est le siège de la chémorégulation centrale. La mutation du facteur de transcription PHOX2B est responsable d'un syndrome d'hypoventilation centrale congénitale, ou syndrome d'Ondine, caractérisé par l'absence de développement des neurones chémosensibles du RTN chez le fœtus et le nouveau-né. Déterminant essentiel de ces neurones le facteur de transcription PHOX2B, lorsqu'il est associé à d'autres marqueurs constitue une carte d'identité moléculaire des neurones chémosensibles du RTN, utilisable pour leur identification en histologie. Chez l'adulte, une dysfonction du RTN semble impliquée dans l'apparition de troubles respiratoires au cours de maladies neurodégénératives comme le Parkinson. Jusqu'alors, cette structure indispensable au contrôle central de la respiration n'a pas été décrite chez l'humain adulte.L'objectif premier de ce travail était de proposer une description anatomique à l'échelle cellulaire, des neurones chémosensibles constituant le noyau rétrotrapézoïde humain. Le second objectif était d'établir les bases nécessaires à une méthode de reconstruction tridimensionnelle de coupes histologiques, couplée à un algorithme de détection automatisée de marquages spécifiques, permettant la visualisation de structures anatomiques identifiées post mortem, au sein d'un organe modélisé à partir de coupes traitées.Une approche de neuro-anatomie comparée a été développée, basée sur l'hypothèse de la préservation de la respiration et de son contrôle au sein de plusieurs espèces de mammifères, correspondant à une organisation anatomique obéissant à des déterminants géniques et moléculaires identiques. Ainsi, le noyau rétrotrapézoïde a été décrit pour la première fois chez le primate non humain adulte, par comparaison aux descriptions faites chez le rat. Après cartographie de l'expression de PHOX2B, des neurones exprimant la pré-pro-galanine étaient retrouvés parmi les neurones PHOX2B+ en région parafaciale. Cette description chez le primate a permis de définir la région d'intérêt du tronc cérébral humain au sein de laquelle ont été identifiés des neurones exprimant la galanine et le transporteur vésiculaire de type 2 du glutamate, marqueurs spécifiques des neurones chémosensibles du noyau rétrotrapézoïde du rat adulte.Par ailleurs les travaux réalisés chez le primate, ont permis l'amélioration et l'implémentation d'algorithmes de détection de marquages en immunohistochimie et hybridation in situ, ensuite reconstruits en trois dimensions. Le développement de cette méthodologie constitue la base nécessaire à la mise au point d'une anatomie tridimensionnelle des centres respiratoires du tronc cérébral humain. Le développement d'une anatomie tridimensionnelle reconstruite à partir de coupes sériées doit permettre le transfert de données neuro-anatomiques à l'échelle cellulaire acquises post mortem, vers l'étude in vivo en imagerie par résonnance magnétique à haute résolution. Couplée à des explorations physiologiques, elle pourrait rendre possible l'exploration de corrélats anatomo-fonctionnels difficilement accessibles avec les niveaux de résolution actuels.

Contains fulltext : 288245.pdf (Publisher’s version ) (Open Access) BACKGROUND: The cerebellum contains more than 50% of the brain's neurons and is involved in social cognition. Cerebellar anatomical atypicalities have repeatedly been reported in individuals with autism. However, studies have yielded inconsistent findings, likely because of a lack of statistical power, and did not capture the clinical and neuroanatomical diversity of autism. Our aim was to better understand cerebellar anatomy and its diversity in autism. METHODS: We studied cerebellar gray matter morphology in 274 individuals with autism and 219 control subjects of a multicenter European cohort, EU-AIMS LEAP (European Autism Interventions-A Multicentre Study for Developing New Medications; Longitudinal European Autism Project). To ensure the robustness of our results, we conducted lobular parcellation of the cerebellum with 2 different pipelines in addition to voxel-based morphometry. We performed statistical analyses with linear, multivariate (including normative modeling), and meta-analytic approaches to capture the diversity of cerebellar anatomy in individuals with autism and control subjects. Finally, we performed a dimensional analysis of cerebellar anatomy in an independent cohort of 352 individuals with autism-related symptoms. RESULTS: We did not find any significant difference in the cerebellum when comparing individuals with autism and control subjects using linear models. In addition, there were no significant deviations in our normative models in the cerebellum in individuals with autism. Finally, we found no evidence of cerebellar atypicalities related to age, IQ, sex, or social functioning in individuals with autism. CONCLUSIONS: Despite positive results published in the last decade from relatively small samples, our results suggest that there is no striking difference in cerebellar anatomy of individuals with autism.

International audience; Background: Basal cell carcinoma (BCC) incidence is steadily increasing but therapeutic solutions remain limited and present a public health challenge.Aims: To identify predictive factors of BCC recurrence after primary free margin excision, with automated methods, by evaluating cell proliferation, the Hedgehog pathway activation and primary cilia.Materials and Methods: This case–control study included 32 patients (16 with recurrence occurring at least 6 months after complete resection, and 16 without recurrence) who underwent surgery for BCC. Formalin-fixed paraffin-embedded cutaneous resections were processed for immunohistochemistry or immunostaining with the following primary antibodies: mouse anti-MCM6, rabbit anti-ARL13B and rabbit anti-GLI1.Results: BCC recurrence after free margin excision was significantly linked to a higher proliferative index (p < 0.001) and a lower cilia count (p = 0.041) in the primary lesion. No significant differences were observed regarding cilia length (p = 0.39) or GLI1-positive nuclei.Discussion: The complex interplay between essential signaling pathways, cell proliferation and cilia requires further experimental investigations in the context of BCC recurrence.Conclusion: A higher proliferative index evaluated with MCM6 antibody could be a useful prognosis marker of BCC risk of recurrence. The lower cilia count in the primary lesion unveiled novel perspectives to understand BCC recurrence molecular mechanisms.

International audience; Sarcomas are clustered in two oncological entities named bone and soft-tissue sarcomas. Both are rare cancers originating from the mesenchyme, characterized by their propensity to induce the development of lung metastases. Sarcoma cells escaping from the primary tumor site, spread to the pulmonary tissue through the bloodstream where they found a favorable microenvironment to establish metastatic foci. The low number of patients, the high histological, genetic and molecular heterogeneity of sarcomas combined with the absence of specific markers expressed by cancer cells make the detection and follow up of the minimal residual disease challenging. Over the last decade, tremendous technological progress has been made towards the detection of recurrent diseases. The literature is now enriched of information describing the use of liquid biopsies in clinical care of sarcoma patients. The present chapter aims to give a brief overview of the most recent data available on the detection of circulating tumor cells and circulating tumor DNA in sarcomas.

We previously identified matrix metalloproteinase 2 (MMP2) and MMP9 plasma levels as candidate biomarkers of bevacizumab activity in patients with recurrent glioblastoma. The aim of this study was to assess the predictive value of MMP2 and MMP9 in a randomized phase III trial in patients with newly diagnosed glioblastoma and to explore their tumor source. In this post hoc analysis of the AVAglio trial (AVAGlio/NCT00943826), plasma samples from 577 patients (bevacizumab, n = 283; placebo, n = 294) were analyzed for plasma MMP9 and MMP2 levels by enzyme-linked immunosorbent assay. A prospective local cohort of 38 patients with newly diagnosed glioblastoma was developed for analysis of tumor characteristics by magnetic resonance imaging and measurement of plasma and tumor levels of MMP9 and MMP2. In this AVAglio study, MMP9, but not MMP2, was correlated with bevacizumab efficacy. Patients with low MMP9 derived a significant 5.2-month overall survival (OS) benefit with bevacizumab (HR 0.51, 95% CI 0.34–0.76, p = 0.0009; median 13.6 vs. 18.8 months). In multivariate analysis, a significant interaction was seen between treatment and MMP9 (p = 0.03) for OS. In the local cohort, we showed that preoperative MMP9 plasma levels decreased after tumor resection and were correlated with tumor levels of MMP9 mRNA (p = 0.03). However, plasma MMP9 was not correlated with tumor size, invasive pattern, or angiogenesis. Using immunohistochemistry, we showed that MMP9 was expressed by inflammatory cells but not by tumor cells. After cell sorting, we showed that MMP9 was expressed by CD45+ immune cells. Finally, using flow cytometry, we showed that MMP9 was expressed by tumor-infiltrating neutrophils. In conclusion, circulating MMP9 is predictive of bevacizumab efficacy and is released by tumor-infiltrating neutrophils.

International audience; White adipose tissue accumulates at various sites throughout the body and some adipose tissue depots exist in close proximity to organs, whose function they could influence in a paracrine manner. Prostate gland is surrounded by a poorly characterized adipose depot called periprostatic adipose tissue (PPAT) playing emerging roles in prostate-related disorders. Unlike all other adipose depots, PPAT secretes pro-inflammatory cytokines even in lean individuals and does not increase in volume during obesity. These unique features remain unexplained due to the poor structural and functional characterization of this tissue. We characterized the structural organization of PPAT in patients in comparison to abdominopelvic adipose tissue (APAT), an extraperitoneal adipose depot whose accumulation is correlated to BMI. Confocal microscopy followed by 3D reconstructions showed a sparse vascular network in PPAT when compared with that in APAT, suggesting that this tissue is hypoxic. Unbiased comparisons of PPAT and APAT transcriptomes found that most differentially expressed genes were related to the hypoxia response. High levels of the hypoxia-inducible factor HIF-2α confirmed the presence of an adaptive response to hypoxia in PPAT. This chronic hypoxic state was associated with inflammation and fibrosis, which were not further upregulated by obesity. This fibrosis and inflammation explain the failure of PPAT to expand in obesity and open new mechanistic avenues to explain its role in prostate-related disorders including cancer

BackgroundIntracranial occlusion recanalization fails in 20% of endovascular thrombectomy procedures, and thrombus composition is likely to be an important factor. In this study, we demonstrate that the combination of electrical impedance spectroscopy (EIS) and machine learning constitutes a novel and highly accurate method for the identification of different human thrombus types.Methods134 samples, subdivided into four categories, were analyzed by EIS: 29 ‘White’, 26 ‘Mixed’, 12 ‘Red’ thrombi, and 67 liquid ‘Blood’ samples. Thrombi were generated in vitro using citrated human blood from five healthy volunteers. Histological analysis was performed to validate the thrombus categorization based on red blood cell content. A machine learning prediction model was trained on impedance data to differentiate blood samples from any type of thrombus and in between the four sample categories.ResultsHistological analysis confirmed the similarity between the composition of in vitro generated thrombi and retrieved human thrombi. The prediction model yielded a sensitivity/specificity of 90%/99% for distinguishing blood samples from thrombi and a global accuracy of 88% for differentiating among the four sample categories.ConclusionsCombining EIS measurements with machine learning provides a highly effective approach for discriminating among different thrombus types and liquid blood. These findings raise the possibility of developing a probe-like device (eg, a neurovascular guidewire) integrating an impedance-based sensor. This sensor, placed in the distal part of the smart device, would allow the characterization of the probed thrombus on contact. The information could help physicians identify optimal thrombectomy strategies to improve outcomes for stroke patients.

Patient-derived tumoroid (PDT) has been developed and used for anti-drug screening in the last decade. As compared to other existing drug screening models, a PDT-based in vitro 3D cell culture model could preserve the histological and mutational characteristics of their corresponding tumors and mimic the tumor microenvironment. However, few studies have been carried out to improve the microvascular network connecting the PDT and its surrounding microenvironment, knowing that poor tumor-selective drug transport and delivery is one of the major reasons for both the failure of anti-cancer drug screens and resistance in clinical treatment. In this study, we formed vascularized PDTs in six days using multiple cell types which maintain the histopathological features of the original cancer tissue. Furthermore, our results demonstrated a vascular network connecting PDT and its surrounding microenvironment. This fast and promising PDT model opens new perspectives for personalized medicine: this model could easily be used to test all therapeutic treatments and could be connected with a microfluidic device for more accurate drug screening.

Correspondence.; International audience; In reply to the correspondence “A combination of sectional micro-anatomy and micro-stereoscopic anatomy is an improved micro-dissection method” by Jing-Zhan Wu and Chun-Hai Tang: We agree with the authors that it is important to collect data using diverse techniques (two and three dimensional) for the best possible understanding of a species' brain structure.The authors speak of “discrepancies,” especially concerning the shape and size of cerebral ventricles, between their study (Wu et al. 2021) conducted on 40-day-old (juvenile) rabbits and our study on 4-day-old (newborn) rabbits (Schneider et al. 2018). They also mention differences observed in the brain of adult rabbits studied by Shek et al. (1986). These are differences, not “discrepancies”, and they are not surprising because the brain changes shape during development, especially in the size and shape of the ventricles (e.g. Scelsi et al. 2020). These same changes occur in rabbits. Most importantly, shortly after birth, the brain of the newborn rabbit changes very rapidly – indeed, we observed clear differences between neonates (0-day-old) (Schneider et al. 2016) and 4-day-old rabbit pups (Schneider et al. 2018). Therefore, it is important that Wu et al. 2021 compare literature describing brain sections of 40-day-old rabbits, or extend their own studies to the brain of 4-day-old rabbit pups, to get a clear understanding of any differences observed. Such differences might not be due to different techniques.

Background The reconstruction of segmental mandibular defects remains a challenge for the reconstructive surgeon, from both a functional and an esthetic point of view. Methods This clinical review examines the different techniques currently in use for mandibular reconstruction as related to a range of etiologies, including the different bone donor sites, the alternatives to free flaps (FFs), as well as the contribution of computer‐assisted surgery. Recent progress and the perspectives in bone tissue engineering (BTE) are also discussed. Results Osseous FF allows reliable and satisfying outcomes. However, locoregional flap, distraction osteogenesis, or even induced membrane techniques are other potential options in less favorable cases. Obtaining an engineered bone with satisfactory mechanical properties and sufficient vascular supply requires further investigations. Conclusions Osseous FF procedure remains the gold standard for segmental mandible reconstruction. BTE strategies offer promising alternatives.

Myotonic dystrophy type 1 (DM1) is the most common adult-onset muscular dystrophy, primarily characterized by muscle wasting and weakness. Many biomarkers already exist in the rapidly developing biomarker research field that aim to improve patients’ care. Limited work, however, has been performed on rare diseases, including DM1. We have previously shown that specific microRNAs (miRNAs) can be used as potential biomarkers for DM1 progression. In this report, we aimed to identify novel serum-based biomarkers for DM1 through high-throughput next-generation sequencing. A number of miRNAs were identified that are able to distinguish DM1 patients from healthy individuals. Two miRNAs were selected, and their association with the disease was validated in a larger panel of patients. Further investigation of miR-223-3p, miR-24-3p, and the four previously identified miRNAs, miR-1-3p, miR-133a-3p, miR-133b-3p, and miR-206-3p, showed elevated levels in a DM1 mouse model for all six miRNAs circulating in the serum compared to healthy controls. Importantly, the levels of miR-223-3p, but not the other five miRNAs, were found to be significantly downregulated in five skeletal muscles and heart tissues of DM1 mice compared to controls. This result provides significant evidence for its involvement in disease manifestation., Graphical abstract, Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy in adults. In this study, two novel miRNAs were identified to be elevated in DM1 patients compared to healthy individuals and suggested as potential biomarkers. Additionally, six miRNAs were investigated in tissues and serum of a DM1 mouse model.

International audience; Live-pathogenic bacteria, which were identified inside tumors hundreds year ago, are key elements in modern cancer research. As they have a relatively accessible genome, they offer a multitude of metabolic engineering opportunities, useful in several clinical fields. Better understanding of the tumor microenvironment and its associated microbiome would help conceptualize new metabolically engineered species, triggering efficient therapeutic responses against cancer. Unfortunately, given the low microbial biomass nature of tumors, characterizing the tumor microbiome remains a challenge. Tumors have a high host versus bacterial DNA ratio, making it extremely complex to identify tumor-associated bacteria. Nevertheless, with the improvements in next-generation analytic tools, recent studies demonstrated the existence of intratumor bacteria inside defined tumors. It is now proven that each cancer subtype has a unique microbiome, characterized by bacterial communities with specific metabolic functions. This review provides a brief overview of the main approaches used to characterize the tumor microbiome, and of the recently proposed functions of intracellular bacteria identified in oncological entities. The therapeutic aspects of live-pathogenic microbes are also discussed, regarding the tumor microenvironment of each cancer type.

In skeletal surgical procedures, bone regeneration in irregular and hard-to-reach areas may present clinical challenges. In order to overcome the limitations of traditional autologous bone grafts and bone substitutes, an extrudable and easy-to-handle innovative partially demineralized allogenic bone graft in the form of a paste has been developed. In this study, the regenerative potential of this paste was assessed and compared to its clinically used precursor form allogenic bone particles. Compared to the particular bone graft, the bone paste allowed better attachment of human mesenchymal stromal cells and their commitment towards the osteoblastic lineage, and it induced a pro-regenerative phenotype of human monocytes/macrophages. The bone paste also supported bone healing in vivo in a guide bone regeneration model and, more interestingly, exhibited a substantial bone-forming ability when implanted in a critical-size defect model in rat calvaria. Thus, these findings indicate that this novel partially demineralized allogeneic bone paste that combines substantial bone healing properties and rapid and ease-of-use may be a promising alternative to allogeneic bone grafts for bone regeneration in several clinical contexts of oral and maxillofacial bone grafting.

Osteosarcoma (OS) is the most common type of primary bone cancer affecting children and adolescents. OS has a high propensity to spread, meaning the disease is often incurable and fatal. There have been no improvements in survival rates for decades. This highlights an urgent need for development of novel therapeutic strategies. In this study, we have produced in vitro and in vivo data that demonstrates the role of purinergic signalling, specifically, the B isoform of the purinergic receptor P2RX7 (herein termed “ P2RX7B”), in OS progression and metastasis. Our data shows that P2RX7B expression confers a survival advantage in TE85+P2RX7B and MNNG-HOS+ P2RX7B human OS cell lines in vitro that is minimised following treatment with A740003, a specific P2RX7 antagonist. P2RX7B expression reduced cell adhesion and P2RX7B activation promoted invasion and migration in vitro, suggesting a probable metastatic phenotype. Using an in vivo OS xenograft model, MNNG-HOS+P2RX7B tumours exhibited ectopic bone formation that was abrogated with A740003 treatment. An increased metastatic phenotype was further demonstrated in vivo as expression of P2RX7B in primary tumour cells increased the propensity of the tumour to metastasise to the lungs. RNA-seq identified a novel gene axis, FN1/LOX/PDGFB/IGFBP3/BMP4, downregulated in response to A740003 treatment. In conclusion, our data indicates for the first time a role for P2RX7B in OS tumour growth, progression and metastasis. We show that P2RX7B is a potential therapeutic target in human OS.Novelty and ImpactWe provide evidence for the pro-tumorigenic role of the B isoform of the P2RX7 purinergic receptor in osteosarcoma (OS). In addition to increasing proliferation, P2RX7B increases the cancerous properties of OS cells, reducing adhesion and increasing migration and invasion. In vivo, P2RX7B does not affect primary tumour growth, but does lead to an increased propensity to metastasize. RNA-seq revealed a new axis of oncogenic genes inhibited by the P2RX7 antagonist and this data could potentially lead to new targets for OS treatment.

International audience; Meningiomas are the most common primary tumors of the central nervous system. Based on the 2021 WHO classification, they are classified into three grades reflecting recurrence risk and aggressiveness. However, the WHO’s histopathological criteria defining these grades are somewhat subjective. Together with reliable immunohistochemical proliferation indices, other molecular markers such as those studied with genome-wide epigenetics promise to revamp the current prognostic classification. In this study, 48 meningiomas of various grades were randomly included and explored for DNA methylation with the Infinium MethylationEPIC microarray over 850k CpG sites. We conducted differential and correlative analyses on grade and several proliferation indices and markers, such as mitotic index and Ki-67 or MCM6 immunohistochemistry. We also set up Cox proportional hazard models for extensive associations between CpG methylation and survival. We identified loci highly correlated with cell growth and a targeted methylation signature of regulatory regions persistently associated with proliferation, grade, and survival. Candidate genes under the control of these regions include SMC4, ESRRG, PAX6, DOK7, VAV2, OTX1, and PCDHA-PCDHB-PCDHG, i.e., the protocadherin gene clusters. This study highlights the crucial role played by epigenetic mechanisms in shaping dysregulated cellular proliferation and provides potential biomarkers bearing prognostic and therapeutic value for the clinical management of meningioma.

International audience; In 2021, as the situation due to COVID-19 pandemic was still uncertain, the 18 th annual meeting of the Interuniversity Institute of Myology (IIM), took place on a virtual platform, following the same organization already tested for the previous edition. Participants from Italy, European countries, Canada and USA included clinicians, scientists, pharmaceutical companies and representatives of patient organizations. Four keynote speakers presented new insights into the modulation of muscle stem cell self-renewal in the treatment of neuromuscular disease, the role of nuclear positioning in muscle function, regeneration and tumorigenesis in the heart and advances on therapies of muscular dystrophies. Young PhD students and trainees presented oral communications distributed in five scientific sessions and posters in two poster sessions. On October 21, 2021, selected young scientists participated in the "High Training Course on Advanced Myology", organized with the University of Perugia, Italy. This course consisted of lectures on muscle regeneration and therapeutic perspectives by internationally recognized speakers, followed by roundtable discussions on "Omics technologies in myology" and "New therapeutic approaches", plus the meeting itself. Young trainees, winners of past IIM conferences, forming the Young IIM Committee, selected one of Keynote speakers and were involved in the organization of scientific sessions and roundtable discussions. The friendly welcoming of the meeting, which has strongly characterized this event and is of great help in facilitating scientific exchanges and stimulating novel collaborations, was the hallmark of the conference this year again, even on virtual platform. Breakthrough studies showing interdisciplinary works are fostering new avenues in the field of myology. This year again, scientists and students attended the meeting at the huger number, challenging the difficulties due to the COVID-19 pandemic. All participants shared the wish to continue and implement IIM meeting with new insights on muscle biology, perspectives in the understanding of the musclerelated diseases and in novel therapeutic approaches. We report here abstracts of the meeting describing basic, translational, and clinical research contributing to the large field of myology.

International audience; Martin Robert L'émeute des fémurs : contestations étudiantes, dissections humaines et professionnalisation de la médecine au Québec Résumé : Les enlèvements de cadavres par les étudiants en médecine font partie des hivers québécois depuis plus de cinquante ans lorsqu'aux mois de janvier et février 1883, les journaux en relèvent au moins quinze dans la région de Montréal. L'un d'entre eux conduit à l'arrestation et au procès de l'étudiant Joseph Fontaine. Venus le soutenir à la cour de police, des confrères étudiants des écoles médicales montréalaises y confrontent les agents qui tentent de les expulser de la salle d'audience. Dans la foulée de cette manifestation, le milieu médical québécois réclame une réforme législative, afin de s'assurer que les établissements publics respectent les dispositions de la loi québécoise d'anatomie concernant le transfert aux écoles de médecine des corps non réclamés. Cet article montre comment cette loi réformée de 1883 marque un tournant, à partir duquel la dissection de corps non réclamés s'installe durablement dans la formation des étudiants en médecine au Québec. Il souligne que son adoption est indissociable des enlèvements de cadavres par des étudiants en médecine et qu'en mettant un terme à cette pratique, elle contribue à instaurer une vision plus policée du professionnalisme médical à la fin du XIX e siècle. Mots-clés : enlèvement des défunts, loi d'anatomie, acte pour amender et refondre les divers actes concernant l'étude de l'anatomie, professionnalisme, dissections, écoles de médecine, méthode anatomo-clinique, Québec.

International audience; No abstract available

International audience; Clinical metagenomics fuels pathogen discovery but a comprehensive research environment is required to address critical questions such as imputability, physiopathology of novel identified infectious agents, and development of new diagnostic tools. The Institut Pasteur, in close collaboration with specialized hospital clinical services and laboratories including (neuro)pathologists, along with other academic labs, seeks to address these topics. We review some of the major identifications done in the course of our historical partnership with hospitals, by highlighting the place and the contribution of research works following identification of new or unexpected microorganisms. The list includes novel human pathogens with a zoonotic potential (Astrovirus VA1, Umbre orthobunyavirus, European Bat Lyssavirus 1) and known pathogens with unexpected or atypical presentation (Rubella virus, Rabies, Dengue).

Japanese quails (Coturnix japonica) divergently selected based on their behavior during a tonic immobility test are an excellent model to study the link between brain morphology and behavior expression. The LTI (Long Tonic Immobility) and STI (Short Tonic Immobility) quail lines differ in their level of emotivity, with LTI quails being selected for their high-trait emotivity. Here, comparing the brain regions of the LTI and STI lines of male Japanese quails, we test the hypothesis that this divergent selection could have influenced brain anatomy, in particular, those regions involved in sensory and emotional processing. The heads of twenty, 10 weeks old male Japanese quails (10 STI and 10 LTI) were imaged ex-vivo using ultra high-resolution (11.7 Tesla) magnetic resonance imaging. The resulting images were used to create a population-averaged quail brain template and manually segmented 3D whole-brain atlas (openly available: https://doi.org/10.5281/zenodo.4700522). The atlas is composed of 191 brain regions, the ventricular system, pineal and pituitary glands. Thanks to this atlas, an exploratory analysis was conducted to compare brain regions between the two lines: the relative volumes of 33 regions were impacted (with 24 larger relative volumes being found in STI). This demonstrates for the first time in male Japanese quail that genetic selection for a specific emotional behavior (tonic immobility) modifies the anatomy of brain regions involved in sensory and emotional processing., This project was supported by the APR Neuro2Co grant (Convention 2017 00117257; coordinator Elodie Chaillou, France) from Région Centre Val de Loire. Marine Siwiaszczyk's PhD was funded by Région Centre Val de Loire and Beauval Nature Foundation. Cyril Poupon and Raissa Yebga Hot received funding from the European Union's Horizon 2020 Framework Program for Research and Innovation under the specific Grants No. 945539 (HBP SGA3). The authors have no relevant financial or non-financial interests to disclose.

International audience; The analysis of circulating tumor cells (CTCs) in blood is a powerful noninvasive alternative to conventional tumor biopsy. Inertial-based separation is a promising highthroughput, marker-free sorting strategy for the enrichment and isolation of CTCs. Here, we present and validate a double spiral microfluidic device that efficiently isolates CTCs with a fine-tunable cutoff value of 9 μm and a separation range of 2 μm. We designed the device based on computer simulations that introduce a novel, customized inertial force term, and provide practical fabrication guidelines. We validated the device using calibration beads, which allowed us to refine the simulations and redesign the device. Then we validated the redesigned device using blood samples and a murine model of metastatic breast cancer. Finally, as a proof of principle, we tested the device using peripheral blood from a patient with hepatocellular carcinoma, isolating more than 17 CTCs/ml, with purity/removal values of 96.03% and 99.99% of white blood cell and red blood cells, respectively. These results confirmhighly efficient CTC isolation with a stringent cut-off value and better separationresults than the state of the art.

International audience; Purpose: The histopathological images contain a huge amount of information, which can make diagnosis an extremely time-consuming and tedioustask. In this study, we developed a completely automated system to detect regions-of-interest (ROIs) in Whole Slide Images (WSI) of Renal Cell Carcinoma (RCC), to reduce time analysis and assist pathologists in making more accurate decisions.Methods: For this purpose, the WSIs are divided into patches at high resolution and a method is proposed to classify the patches into a tumor andhealthy tissue. The proposed approach is based on an e cient texture descriptor named Dominant Rotated Local Binary Pattern (DRLBP) and colortransformation (H and V channels) to reveal and exploit the immense texture variability at the microscopic high magni cations level. Thereby, the DRLBPs retain the structural information and utilize the magnitude values in a local neighborhood for more discriminative power. For the classication of the relevant ROIs, feature extraction of WSIs patches was performed on the color channels separately to form the histograms. Next, we used the most frequently occurring patterns as a feature selection step to discard non-informative features. The performances of di erent classi ers (k-NN, SVM and RF) on a set of 1800 kidney cancer patches originating from 12 whole slide images, were compared and evaluated. Furthermore, the small size of the image dataset allows to investigate deep learning approach based on transfer learning for image patches classi cation by using deep features (VGG-16) and ne-tuning (ResNet-50) methods.Results: High recognition accuracy was obtained and the classi ers are efficient, the best precision result was 99.17% achieved with SVM. Moreover, transfer learning models perform well with comparable performance, and the highest precision using ResNet-50 reached 98.50%. The proposed approach results revealed a very e cient image classi cation and demonstrated e cacy in identifying ROIs.Conclusion: This study presents an automatic system to detect regions of interest relevant to the diagnosis of kidney cancer in whole-slide histopathology images.