Le lymphome B riche en cellules T chez le chat : étude clinique, histologique et immunophénotypique de 12 cas

Dans le but de définir les caractéristiques cliniques, histologiques et immunophénotypiques du lymphome B riche en cellules T (LBRCT) chez le chat, nous avons analysés 12 cas de lymphomes félins présentant une composition cellulaire polymorphe incluant un mélange de petites et grandes cellules lymphoïdes. Malgré une apparence histologique homogène, les données immunohistochimiques nous ont permis de différencier trois types de lymphomes : le sarcome histiocytaire (n=1), le LBRCT (n=6) et le lymphome B diffus à grandes cellules (n=5). Le tableau clinique du LBRCT se caractérise par une atteinte nodale périphérique localisée aux noeuds lymphatiques cervicaux (n=3), au noeud lymphatique axillaire accessoire (n=1) ou généralisée à l'ensemble des noeuds lymphatiques périphériques (n=2). Les durées de survie sont extrêmement variables et s'étendent sur 1 à 18 mois. L'aspect microscopique révèle un remaniement important de l'architecture du noeud lymphatique par une infiltration : diffuse (n=2), nodulaire à diffuse (n=3) ou nodulaire (n=1). La population cellulaire quant à elle, est caractérisée par la présence de grandes cellules atypiques éparpillées sur un fond uniforme de petits lymphocytes représentant plus de 50% de la population cellulaire totale. A l'examen immunohistochimique, les cellules atypiques expriment deux marqueurs de lymphocytes B : le BLA36 et le CD79, tandis que la population de petits lymphocytes exprime soit le CD3 (marqueur de lymphocytes T) soit le CD79. Ces données présentent des similitudes avec les précédentes études sur le LBRT chez le chat. Néanmoins ces résultats sont à nuancer dans la mesure où nous ne disposons pas à l'heure actuelle en médecine vétérinaire des moyens nécessaire à la différenciation du LBRT et du lymphome Hodgkinien à prédominance lymphocytaire

Quantification of the density of cooperative neighboring synapses required to evoke endocannabinoid signaling

The spatial pattern of synapse activation may impact on synaptic plasticity. This applies to the synaptically-evoked endocannabinoid-mediated short-term depression at the parallel fiber (PF) to Purkinje cell synapse, the occurrence of which requires close proximity between the activated synapses. Here, we determine quantitatively this required proximity, helped by the geometrical organization of the cerebellar molecular layer. Transgenic mice expressing a calcium indicator selectively in granule cells enabled the imaging of action potential-evoked presynaptic calcium rise in isolated, single PFs. This measurement was used to derive the number of PFs activated within a beam of PFs stimulated in the molecular layer, from which the density of activated PFs (input density) was calculated. This density was on average 2.8μm in sagittal slices and twice more in transverse slices. The synaptically-evoked endocannabinoid-mediated suppression of excitation (SSE) evoked by ten stimuli at 200Hz was determined from the monitoring of either postsynaptic responses or presynaptic calcium rise. The SSE was significantly larger when recorded in transverse slices, where the input density is larger. The exponential description of the SSE plotted as a function of the input density suggests that the SSE is half reduced when the input density decreases from 6 to 2μm. We conclude that, although all PFs are truncated in an acute sagittal slice, half of them remain respondent to stimulation, and activated synapses need to be closer than 1.5μm to synergize in endocannabinoid signaling. © 2013 The authors

Metacommunity Dynamics: Decline of Functional Relationship along a Habitat Fragmentation Gradient

Background: The metacommunity framework is crucial to the study of functional relations along environmental gradients. Changes in resource grain associated with increasing habitat fragmentation should generate uncoupled responses of interacting species with contrasted dispersal abilities. Methodology/Principal Findings: Here we tested whether the intensity of parasitism was modified by increasing habitat fragmentation in the well know predator-prey system linking the parasitoid Cotesia glomerata (Hymenoptera: Braconidae) to its main host Pieris brassicae (Lepidoptera: Pieridae). We collected information on herbivorous abundance and parasitism rate along an urbanization gradient from the periphery to the centre of Paris. We showed that butterfly densities were not influenced by habitat fragmentation, whereas parasitism rate sharply decreased along this gradient. Conclusions/Significance: Our results provide novel insights into the mechanisms underlying the persistence of species in highly fragmented areas. They suggest that differential dispersal abilities could alter functional relationships between prey and predator, notably by a lack of natural predators

Etude de l'élaboration d'oxyde transparent conducteur de type-p en couches minces pour des applications à l'électronique transparente ou au photovoltaïque

Transparent electronic is currently limited by the lack of a really performant p-type transparent conducting oxide (TCO), which makes the elaboration of a transparent p-n junction challenging. Cuprous oxide Cu2O is a promising p-type TCO, but its optical transmittance in the visible spectrum is limited by its relatively low band gap (2.1 eV). In this thesis, we aim at increasing this value. To achieve that, we explore MOCVD as the growth method for strontium and calcium doping of cuprous oxide. According to ab-initio calculations performed at Tyndall Institute in Cork, doping with these elements is supposed to increase the band gap of Cu2O. In chapter I, we introduce the context of this thesis. After explaining the required conditions that a material must fulfil to be a p-type TCO, we present the state of the art of Cu2O. In chapter II, we present all the techniques used in this work, from the elaboration (MOCVD, thermal annealing) to characterization (SEM, TEM, AFM, XRD, FTIR, Raman spectroscopy, XPS, UV-vis-NIR spectroscopy, 4 point probe and Hall effect measurement). In chapter III, our objective is to synthesize pure, undoped Cu2O thin films. We explore the influence of the MOCVD parameters on the films composition and morphology. We get homogenous films on Si/SiO2 substrates, while we get heterogeneous films with un-deposited parts on silicon substrate. In addition, we show the risk to get the metallic copper phase when precursor concentration is high, oxygen partial pressure is low, and/or temperature is high. This enables us to determine the optimal deposition conditions. Starting from those optimal conditions, we study the influence of strontium doping on the functional properties of the films (resistivity, band gap and visible light transmittance) in chapter IV. A decrease of resistivity was observed with strontium doping. While undoped films show resistivity values of 103 Ω.cm or more, films doped from 6 to 15% strontium show resistivity values of about 10 Ω.cm. P-type conductivity was confirmed through Hall effect measurements, with a mobility close to 10 cm2.V-1.s-1 and a charge carrier density of about 1016 cm-3. The large difference between this carrier density and the Sr concentration can be linked with the presence of a strontium carbonate and fluoride contamination that was detected by FTIR and XPS. The exact influence of those impurities is not well known. In addition, no significant variation of optical properties was observed, the band gap remained close to 2.4 eV and average transmittance in the 500-1000 nm range was about 55%. Similar tendencies were observed for calcium doping, addressed in chapter V. Calcium doping showed the particularity of leading to the presence of cavities localized at the substrate/Cu2O interface, for a high dopant concentration and under UV assistance. Eventually, we performed thermal annealing on some samples, doped and undoped, in chapter VI. For undoped samples, it allowed to decrease resistivity in the 10-100 Ω.cm range. For doped samples, it allows samples showing initial resistivity of about 10 Ω.cm to decrease it to 1 Ω.cm. No impact of thermal annealing on sample morphology or composition was observed. In this thesis, we successfully established the effects of Sr or Ca doping, which lead to a significant decrease of the resistivity without impact on the optical properties, unlike what was predicted by the ab initio calculations. We were thus able to improve the p-type transparent Cu2O thin films properties.L'électronique transparente est actuellement limitée par la difficulté de construire une jonction p-n transparente, en raison du manque d'oxyde transparent conducteur (TCO) de type p réellement performant. L'oxyde cuivreux Cu2O est un TCO de type p prometteur, mais sa bande interdite relativement étroite pour un TCO (2,1 eV), limite sa transmittance dans le domaine visible. Dans le cadre de cette thèse, nous cherchons à augmenter cette valeur. Pour cela, nous explorons la méthode MOCVD comme technique de dépôt pour le dopage au strontium et au calcium de l’oxyde cuivreux. Ce dopage est supposé élargir la bande interdite du Cu2O d'après des calculs ab initio effectués à l'institut Tyndall, à Cork. Dans le chapitre I, nous présentons le contexte de cette thèse. Après avoir expliqué les conditions que doit remplir un matériau pour être un TCO de type p, nous présentons l'état de l'art concernant le Cu2O. Dans le chapitre II, nous présentons l'ensemble des techniques utilisées dans le cadre de cette thèse, de l'élaboration (MOCVD, recuits thermiques) à la caractérisation (MEB, MET, AFM, DRX, spectroscopie FTIR, spectroscopie Raman, XPS, spectroscopie UV-vis-NIR, mesures 4 pointes et mesures d'effet Hall). Au cours du chapitre III, l'influence des paramètres de la MOCVD sur la composition et la morphologie a été analysée pour l’élaboration de couches de Cu2O pures, non dopées en vue d'établir les conditions optimales de dépôt. Nous obtenons des couches continues sur substrat de Si/SiO2, alors qu'elles sont systématiquement hétérogènes avec des zones sans dépôt sur silicium. En outre, nous mettons en évidence le risque d'obtenir la phase cuivre métallique lorsque la concentration de précurseur est élevée, la pression partielle d'oxygène faible et/ou la température élevée. Partant de ces conditions optimales, nous étudions dans le chapitre IV l'influence du dopage au strontium sur les propriétés fonctionnelles des couches (résistivité, largeur de bande interdite et transmittance dans le visible). Une chute de la résistivité a été observée lors du dopage au strontium. Les couches non dopées ont des résistivités de l'ordre de 103 Ω.cm ou plus, contre 10 Ω.cm pour les couches contenant entre 6 et 15% de strontium. La conductivité est bien de type p avec une mobilité de l’ordre de 10 cm2.V-1.s-1 et une densité de porteur de quelques 1016 cm-3. L’écart très grand entre cette densité de porteur et la teneur globale en Sr est lié à la présence d’une contamination des couches par du carbonate et du fluorure de strontium mis en évidence par FTIR et XPS. L’influence réelle de ces impuretés n’a pu être déterminée. Enfin il n'a pas été constaté de variation significative des propriétés optiques, la bande interdite restant large d'environ 2,4 eV et la transmittance moyenne entre 500 et 1000 nm de l'ordre de 55%. Des tendances similaires sont observées dans le chapitre V qui aborde le dopage au calcium, avec comme particularité le fait pour un fort taux de dopage et sous assistance UV, d'aboutir à la présence d'espaces vides localisés à l'interface substrat/Cu2O qui pourrait être lié à la décomposition du carbonate de calcium. Finalement, nous procédons à des recuits thermiques des couches, dopées ou non, dans le chapitre VI. Pour les couches non dopées, cela permet de diminuer la résistivité jusqu’à des valeurs de 10-100 Ω.cm. Pour les couches dopées, cela permet aux couches ayant une résistivité initiale de 10 Ω.cm de descendre jusqu'à 1 Ω.cm. Au cours de cette thèse, nous avons établi les effets du dopage au Sr ou Ca qui conduisent à une forte chute de résistivité sans impact sur les propriétés optiques à la différence des résultats prévus par les calculs ab initio. Nous sommes ainsi parvenus à améliorer les propriétés des couches Cu2O transparentes de type p

Renal cell carcinoma: An update for the practicing urologist

AbstractSystemic therapy for metastatic renal cell carcinoma (mRCC) has evolved drastically, with agents targeting vascular endothelial growth factor (VEGF) and the mammalian target of rapamycin (mTOR) now representing a standard of care. The present paper is to review the current status of relevant clinical trials that were either recently completed or ongoing. (1) Though observation remains a standard of care following resection of localized disease, multiple trials are underway to assess VEGF- and mTOR-directed therapies in this setting. (2) While the preponderance of retrospective data favors cytoreductive nephrectomy in the context of targeted agents, prospective data to support this approach is still forthcoming. (3) The first-line management of mRCC may change substantially with multiple studies exploring vaccines, immune checkpoint inhibitors, and novel targeted agents currently underway. In general, prospective studies that will report within the next several years will be critical in defining the role of adjuvant therapy and cytoreductive nephrectomy. Over the same span of time, the current treatment paradigm for first-line therapy may evolve

Colcha de Retalhos: um álbum de família

Resumo: de um trabalho etnográfico desenvolvido na cidade de Goiás, sobre uma colcha de retalhos1, foi possível fazer emergir lembranças impregnadas em cada pedaço de tecido, todos provenientes de sobras de roupas de um núcleo familiar - uma pequena sociedade composta por indivíduos, cada um com sua história. Somadas aos depoimentos recolhidos, as pesquisas sobre a confecção da colcha pode revelar momentos particulares com representatividade coletiva e, como um arquivo de memória, tal qual um álbum de fotografias, a colcha abriu-se para um exercício de rememoração de um grupo, de uma região, de uma época. Palavras-chave: colcha de Retalhos. Memória. História

Abaques virtuels pour l'optimisation géométrique de structures

Malgré le progrès constant des moyens informatiques ces dernières années, les essais expérimentaux conservent une place prépondérante lors de la conception de structures dans l’industrie, car la résolution numérique de modèles complexes de grande taille demeure encore souvent hors de portée. Et même lorsque la simulation est possible, chaque nouvelle structure conçue en bureau d’études est abordée comme un nouveau problème, traité de manière indépendante des cas déjà étudiés, ce qui conduit à un très grand nombre de simulations. Le recours à des essais expérimentaux ainsi qu’à ces multiples simulations entraîne des coûts temporels et financiers importants dont la réduction est un enjeu crucial. L’idée développée ici, consiste à regrouper les structures semblables (qui ne diffèrent que par les valeurs données à un certain jeu de paramètres) en « familles » et à précalculer la solution générale pour chacune des familles sous forme paramétrée. Les quantités d’intérêt utiles au dimensionnement sont alors stockées dans des « abaques virtuels » qui seront utilisés en quasi temps réel par l’ingénieur lors de la phase de conception en particularisant les solutions pour les valeurs de paramètres considérées. La construction de ces abaques est basée sur la méthode de réduction de modèle PGD (Proper Generalized Decomposition [1][2]) qui permet de générer la solution d’un problème paramétré pour l’ensemble des jeux de paramètres. Dans le cadre de cette étude avec ASTRIUM-ST, les abaques virtuels sont créés pour prendre en compte les variations de géométrie, qui sont un des points clés dans le processus de conception. Il s’agit alors de considérer ces variations géométriques comme des paramètres dans la méthode PGD. Cette approche a été validée dans un premier temps sur des exemples académiques bi-dimensionnels. Elle sera appliquée par la suite à des structures plus complexes afin de se rapprocher des exigences industrielles d’ASTRIUM-ST. [1] P. Ladevèze. Nonlinear Computational Structural Mechanics—New Approaches and Non-Incremental Methods of Calculation, Springer Verlag, 1999. [2] P. Ladevèze, J.C. Passieux, D. Néron. The LATIN multiscale computational method and the Proper Generalized Decomposition. Computer Methods in Applied Mechanics and Engineering, 199:1287-1296, 2010

Impact and compression after impact experimental study of a composite laminate with a cork thermal shield

The aim of this paper is to present an experimental study of impact and compression after impact (CAI) tests performed on composite laminate covered with a cork thermal shield (TS) intended for launchers fairing. Drop weight impact tests have been performed on composite laminate sheets with and without TS in order to study its effect on the impact damage. The results show the TS is a good mechanical protection towards impact as well as a good impact revealing material. Nevertheless, totally different damage morphology is obtained during the impact test with or without TS, and in particular at high impact energy, the delaminated area is larger with TS. Afterwards, CAI tests have been performed in order to evaluate the TS effect on the residual strength. The TS appears to increase the residual strength for a same impact energy, but at the same time, it presents a decrease in residual strength before observing delamination. In fact, during the impact tests with TS, invisible fibres’ breakages appear before delamination damage contrary to the impacts on the unshielded sheets

Homeostatic Reinforcement Theory Accounts for Sodium Appetitive State- and Taste-Dependent Dopamine Responding

Seeking and consuming nutrients is essential to survival and the maintenance of life. Dynamic and volatile environments require that animals learn complex behavioral strategies to obtain the necessary nutritive substances. While this has been classically viewed in terms of homeostatic regulation, recent theoretical work proposed that such strategies result from reinforcement learning processes. This theory proposed that phasic dopamine (DA) signals play a key role in signaling potentially need-fulfilling outcomes. To examine links between homeostatic and reinforcement learning processes, we focus on sodium appetite as sodium depletion triggers state- and taste-dependent changes in behavior and DA signaling evoked by sodium-related stimuli. We find that both the behavior and the dynamics of DA signaling underlying sodium appetite can be accounted for by a homeostatically regulated reinforcement learning framework (HRRL). We first optimized HRRL-based agents to sodium-seeking behavior measured in rodents. Agents successfully reproduced the state and the taste dependence of behavioral responding for sodium as well as for lithium and potassium salts. We then showed that these same agents account for the regulation of DA signals evoked by sodium tastants in a taste- and state-dependent manner. Our models quantitatively describe how DA signals evoked by sodium decrease with satiety and increase with deprivation. Lastly, our HRRL agents assigned equal preference for sodium versus the lithium containing salts, accounting for similar behavioral and neurophysiological observations in rodents. We propose that animals use orosensory signals as predictors of the internal impact of the consumed good and our results pose clear targets for future experiments. In sum, this work suggests that appetite-driven behavior may be driven by reinforcement learning mechanisms that are dynamically tuned by homeostatic need.NIHANRPeer Reviewe

Construção e validação de conteúdos clínicos para desenvolvimento de objetos de aprendizagem

Objective: to describe the process of construction and validation of clinical contents for health learning objects, aimed at patients in the treatment of head and neck cancer. Method: descriptive, methodological study. The development of the script and the storyboard were based on scientific evidence and submitted to the appreciation of specialists for validation of content. The agreement index was checked quantitatively and the suggestions were qualitatively evaluated. Results: The items described in the roadmap were approved by 99% of expert experts. The suggestions for adjustments were inserted in their entirety in the final version. The free-marginal kappa statistical test, for multiple evaluators, presented value equal to 0.68%, granting a substantial agreement. Conclusion: The steps taken in the construction and validation of the content for the production of educational material for patients with head and neck cancer were adequate, relevant and suitable for use in other subjects.Objetivo: descrever o processo de construção e validação de conteúdos clínicos para objetos de aprendizagem em saúde, direcionados aos pacientes em tratamento do câncer de cabeça e pescoço. Método: estudo descritivo, metodológico. O desenvolvimento do roteiro e o storyboard foram fundamentados em evidências científicas e submetidos à apreciação de especialistas para validação de conteúdo. Verificou-se o índice de concordância, quantitativamente, e avaliaram-se qualitativamente as sugestões. Resultados: os itens descritos no roteiro foram aprovados por 99% dos especialistas peritos. As sugestões de ajustes foram inseridas, em sua totalidade, na versão final. O teste estatístico kappa free-marginal, para múltiplos avaliadores, apresentou valor igual a 0,68%, conferindo uma concordância substancial. Conclusão: os passos adotados no percurso de construção e validação do conteúdo para produção de material educativo destinado aos pacientes com câncer de cabeça e pescoço mostraram-se adequados, relevantes e passíveis de serem utilizados em outras temáticas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Fed Sao Paulo, Paulista Nursing Sch, Postgrad Program Nursing, Sao Paulo, BrazilCity Hope Comprehens Canc Ctr, Dept Med Oncol & Expt Therapeut, Duarte, CA USAUniv Fed Sao Paulo, Paulista Nursing Sch, Postgrad Program Nursing, Sao Paulo, BrazilFAPESP: 2015/09139-7Web of Scienc