134 resultados para integration of modalities
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Background: To evaluate the long-term efficacy of multilayer amniotic membrane transplantation for reconstruction of epithelium and stroma in non-traumatic corneal perforations (less than 2 mm) or deep ulcers with descemetocele.Design: Retrospective, non-comparative, interventional case series.Patients and Methods: Eleven consecutive patients with non-traumatic corneal perforations or deep corneal ulcers with descemetocele refractory to conventional treatments: herpetic or zoster keratitis (n = 4), Sjögren's syndrome (n = 2), rosacea (n = 1), hydrops (n = 1), mucous membrane pemphigoid (n = 1), bacterial keratitis (n = 1) and perforation after protontherapy for melanoma (n = 1). Intervention was: multilayer amniotic membrane transplantation with cryopreserved amniotic membrane. Complication rate and clinical outcome were evaluated in this long-term follow-up.Results: Mean follow-up was 32 months (12 to 60). Integration of the multilayer amniotic membrane was obtained in 10 cases after one year. Corneal epithelium healed above the membrane in 10 cases within 3 weeks and remained stable after 32 months in 9 cases. Thickness of the stroma was increased and remained stable during the follow-up in 9 cases. In one case herpetic keratitis recurred with a corneal perforation. The clearing of the amniotic membrane was gradually obtained over a period of 11 months. Complications occurred in 15 % of the eyes during the long-term follow-up.Conclusion: Multilayer amniotic membrane transplantation is a safe and efficient technique for a long restoration of the corneal integrity after non-traumatic corneal perforations or deep corneal ulcers with descemetocele. Long-term prognosis of these eyes depends of the gravity of the initial disease.
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1. Abstract Cervical cancer is thought to be the consequence of infection by human papillomaviruses (HPV). In the majority of cases, DNA from HPV type 16 (HPV16) is found in malignant cervical lesions. The initial steps leading to transformation of an infected cell are not clearly understood but in most cases, disruption and integration of the episomal viral DNA must take place. As a consequence, the E2 and E4 genes are usually not expressed whereas the E6 and E7 oncogenes are highly expressed. However, in a normal infection in which the viral DNA is maintained as an episome, all viral genes are expressed. The pattern according to which the viral proteins are made, and therefore the life cycle of the virus, is tightly linked to the differentiation process of the host keratinocyte. The study of the viral oncogenes E6 and E7 has revealed crucial functions in the process of malignant transformation such as degradation of the p53 tumor suppressor protein, deregulation of the Retinoblastoma protein pathway and activation of the telomerase ribonucleoprotein. All these steps are necessary for cancerous lesions to develop. However, the loss of the E2 gene product seems to be necessary for sufficient expression of E6 and E7 in order to achieve such effects. In normal infections, the E4 protein is made abundantly in the later stages of the viral life cycle. Though extensive amounts of work have been carried out to define the function of E4, it still remains unclear. In this study, several approaches have been used to try and determine the functions of E4. First, a cell-penetrating fusion protein was designed and produced in order to circumvent the chronic difficulties of expressing E4 in mammalian cells. Unfortunately, this approach was not successful due to precipitation of the purified fusion protein. Second, the observation that E4 accumulates in cells having modified their adhesion properties led to the hypothesis that E4 might be involved in the differentiation process of keratinocytes. Preliminary results suggest that E4 triggers differentiation. Last, as E4 has been reported to collapse the cytokeratin network of keratinocytes, a direct approach using atomic force microscopy has allowed us to test the potential modification of mechanical properties of cells harboring reorganized cytokeratin networks. If so, a potential role for E4 in viral particle release could be hypothesized. 2. Résumé Il a été établi que le cancer du col de l'utérus se développe essentiellement à la suite d'une infection par le virus du papillome humain (HPV). Dans la majorité des cas analysés, de l'ADN du HPV de type 16 (HPV16) est détecté. Les étapes initiales de la transformation d'une cellule infectée sont mal connues mais il semble qu'une rupture du génome viral, normalement épisomal, suivi d'une intégration dans le génome de la cellule hôte soient des étapes nécessaires dans la plupart des cas. Or il semble qu'il y ait une sélection pour les cas où l'expression des oncogènes viraux E6 et E7 soit favorisée alors que l'expression des gènes E2 et E4 est en général impossible. Par contre, dans une infection dite normale où le génome viral n'est pas rompu, il n'y pas développement de cancer et tous les gènes viraux sont exprimés. L'ordre dans lequel les protéines virales sont produites, et donc le cycle de réplication du virus, est intimement lié au processus de différentiation de la cellule hôte. L'étude des protéines oncogènes E6 et E7 a révélé des fonctions clés dans le processus de transformation des cellules infectées telles que la dégradation du suppresseur de tumeur p53, la dérégulation de la voie de signalisation Rb ainsi que l'activation de la télomérase. Toutes ces activités sont nécessaires au développement de lésions cancéreuses. Toutefois, il semble que l'expression du gène E2 doit être empêchée afin que suffisamment des protéines E6 et E7 soient produites. Lorsque le gène E2 est exprimé, et donc lorsque le génome viral n'est pas rompu, les protéines E6 et E7 n'entraînent pas de telles conséquences. Le gène E4, qui se trouve dans la séquence codante de E2, a aussi besoin d'un génome viral intact pour être exprimé. Dans une infection normale, le gène E4 est exprimé abondamment dans les dernières étapes de la réplication du virus. Bien que de nombreuses études aient été menées afin de déterminer la fonction virale à E4, aucun résultat n'apparaît évident. Dans ce travail, plusieurs approches ont été utilisées afin d'adresser cette question. Premièrement, une protéine de fusion TAT-E4 a été produite et purifiée. Cette protéine, pouvant entrer dans les cellules vivantes par diffusion au travers de la membrane plasmique, aurait permis d'éviter ainsi les problèmes chroniques rencontrés lors de l'expression de E4 dans les cellules mammifères. Malheureusement, cette stratégie n'a pas pu être utilisée à cause de la précipitation de la protéine purifiée. Ensuite, l'observation que E4 s'accumule dans les cellules ayant modifié leurs propriétés d'adhésion a suggéré que E4 pourrait être impliqué dans le procédé de différentiation des kératinocytes. Des résultats préliminaires supportent cette possibilité. Enfin, il a été montré que E4 pouvait induire une réorganisation du réseau des cytokératines. Une approche directe utilisant le microscope à force atomique nous a ainsi permis de tester une potentielle modification des propriétés mécaniques de cellules ayant modifié leur réseau de cytokératines en présence de E4. Si tel est le cas, un rôle dans la libération de particules virales peut être proposé pour E4.
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PURPOSE OF REVIEW: Multimodal monitoring (MMM) is routinely applied in neurointensive care. Unfortunately, there is no robust evidence on which MMM-derived physiologic variables are the most clinically relevant, how and when they should be monitored, and whether MMM impacts outcome. The complexity is even higher because once the data are continuously collected, interpretation and integration of these complex physiologic events into targeted individualized care is still embryonic. RECENT FINDINGS: Recent clinical investigation mainly focused on intracranial pressure, perfusion of the brain, and oxygen availability along with electrophysiology. Moreover, a series of articles reviewing the available evidence on all the MMM tools, giving practical recommendations for bedside MMM, has been published, along with other consensus documents on the role of neuromonitoring and electroencephalography in this setting. SUMMARY: MMM allows comprehensive exploration of the complex pathophysiology of acute brain damage and, depending on the different configuration of the pathological condition we are treating, the application of targeted individualized care. Unfortunately, we still lack robust evidence on how to better integrate MMM-derived information at the bedside to improve patient management. Advanced informatics is promising and may provide us a supportive tool to interpret physiologic events and guide pathophysiological-based therapeutic decisions.
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The current challenge in a context of major environmental changes is to anticipate the responses of species to future landscape and climate scenarios. In the Mediterranean basin, climate change is one the most powerful driving forces of fire dynamics, with fire frequency and impact having markedly increased in recent years. Species distribution modelling plays a fundamental role in this challenge, but better integration of available ecological knowledge is needed to adequately guide conservation efforts. Here, we quantified changes in habitat suitability of an early-succession bird in Catalonia, the Dartford Warbler (Sylvia undata) ― globally evaluated as Near Threatened in the IUCN Red List. We assessed potential changes in species distributions between 2000 and 2050 under different fire management and climate change scenarios and described landscape dynamics using a spatially-explicit fire-succession model that simulates fire impacts in the landscape and post-fire regeneration (MEDFIRE model). Dartford Warbler occurrence data were acquired at two different spatial scales from: 1) the Atlas of European Breeding Birds (EBCC) and 2) Catalan Breeding Bird Atlas (CBBA). Habitat suitability was modelled using five widely-used modelling techniques in an ensemble forecasting framework. Our results indicated considerable habitat suitability losses (ranging between 47% and 57% in baseline scenarios), which were modulated to a large extent by fire regime changes derived from fire management policies and climate changes. Such result highlighted the need for taking the spatial interaction between climate changes, fire-mediated landscape dynamics and fire management policies into account for coherently anticipating habitat suitability changes of early succession bird species. We conclude that fire management programs need to be integrated into conservation plans to effectively preserve sparsely forested and early succession habitats and their associated species in the face of global environmental change.
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Durant les deux derniers siècles avant notre ère, des objets de type italique, c'est-à-dire caractérisant la culture matérielle de l'Italie tardo-républicaine apparaissent progressivement en Gaule. L'identification de ces objets du quotidien et leur analyse typologique et contextuelle permettent une approche renouvelée du phénomène de romanisation de la Gaule. L'objectif de cette thèse est de mettre en exergue les modalités chronologiques, spatiales et culturelles de la diffusion de ce type de mobilier. La confrontation des résultats avec les données issues des études céramologiques et architecturales permet de brosser un tableau affiné du processus d'acculturation. La nature des sites, ainsi que la diversité des types d'objets considérés permettent de souligner la variété des comportements des populations locales face à la réception de ces mobiliers exogènes. Que ce soit dans le commerce ou en intégrant l'armée romaine, les élites locales ont joué un rôle majeur au sein des interactions avec l'Italie, de la diffusion de ces objets et de l'intégration des nouveaux modèles italiques. -- For the last two centuries before our era, italic type objects, which means objects that are characterizing the material culture of Tardo-republican Italia, are progressively appearing in Gaul. The identification of these everyday objects and their typological and contextual analysis allow a renewed approach of the Gaul romanization phenomenon. The objective of this thesis is to highlight, the chronological, spatial and cultural modalities of the diffusion of such furniture. The comparison of the results with the data provided by the ceramological and architectural studies allows to improve the description of the acculturation process.The behavioral diversity towards the reception of exogenous furniture is underlined by the nature of the sites and the diversity of the considered objects. Local elites, whether by participating in commercial exchanges or by joining the army, have played a major role in the interactions with Italia, from the diffusion of these objects to the integration of the new italic models.
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This research examines the impacts of the Swiss reform of the allocation of tasks which was accepted in 2004 and implemented in 2008 to "re-assign" the responsibilities between the federal government and the cantons. The public tasks were redistributed, according to the leading and fundamental principle of subsidiarity. Seven tasks came under exclusive federal responsibility; ten came under the control of the cantons; and twenty-two "common tasks" were allocated to both the Confederation and the cantons. For these common tasks it wasn't possible to separate the management and the implementation. In order to deal with nineteen of them, the reform introduced the conventions-programs (CPs), which are public law contracts signed by the Confederation with each canton. These CPs are generally valid for periods of four years (2008-11, 2012-15 and 2016-19, respectively). The third period is currently being prepared. By using the principal-agent theory I examine how contracts can improve political relations between a principal (Confederation) and an agent (canton). I also provide a first qualitative analysis by examining the impacts of these contracts on the vertical cooperation and on the implication of different actors by focusing my study on five CPs - protection of cultural heritage and conservation of historic monuments, encouragement of the integration of foreigners, economic development, protection against noise and protection of the nature and landscape - applied in five cantons, which represents twenty-five cases studies.
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BACKGROUND: Root-colonizing fluorescent pseudomonads are known for their excellent abilities to protect plants against soil-borne fungal pathogens. Some of these bacteria produce an insecticidal toxin (Fit) suggesting that they may exploit insect hosts as a secondary niche. However, the ecological relevance of insect toxicity and the mechanisms driving the evolution of toxin production remain puzzling. RESULTS: Screening a large collection of plant-associated pseudomonads for insecticidal activity and presence of the Fit toxin revealed that Fit is highly indicative of insecticidal activity and predicts that Pseudomonas protegens and P. chlororaphis are exclusive Fit producers. A comparative evolutionary analysis of Fit toxin-producing Pseudomonas including the insect-pathogenic bacteria Photorhabdus and Xenorhadus, which produce the Fit related Mcf toxin, showed that fit genes are part of a dynamic genomic region with substantial presence/absence polymorphism and local variation in GC base composition. The patchy distribution and phylogenetic incongruence of fit genes indicate that the Fit cluster evolved via horizontal transfer, followed by functional integration of vertically transmitted genes, generating a unique Pseudomonas-specific insect toxin cluster. CONCLUSIONS: Our findings suggest that multiple independent evolutionary events led to formation of at least three versions of the Mcf/Fit toxin highlighting the dynamic nature of insect toxin evolution.
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The untargeted integration of foreign DNA into the mammalian cell genome, extensively used in gene therapy and biotechnology, remains an incompletely understood process. It is believed to be based on cellular DNA double strand break (DSB) repair machinery and to involve two major steps: i) the formation of long gene arrays (concatemers), and ii) recombination of the resulting concatemer with the genome. The main DSB repair pathways in eukaryotes include non-homologous end-joining (NHEJ), homologous recombination (HR), and microhomology-mediated end-joining (MMEJ). However, it is still not clear, which of these pathways are responsible for transgene integration. Here, we show that NHEJ is not the primary pathway used by mammalian cells in the transgene integration process, while the components of the HR pathway seem to be important for genomic integration but not concatemerization. Instead, concatemer formation appears to be mediated by a subset of the MMEJ pathway, termed synthesis-dependent MMEJ (SD-MMEJ). This mechanism also seems to be preferentially used for plasmid integration into the genome, as confirmed by the analysis of plasmid-to-genome junction sequences, which were found to display an SD-MMEJ pattern. Therefore, we propose the existence of two distinct SD-MMEJ subpathways, relying on different subsets of enzymes. One of these mechanisms appears to be responsible for concatemerization, while the other mechanism, partially dependent in HR enzymes, seems to mediate recombination with the genome. Previous studies performed by our group suggested that matrix attachment regions (MARs), which are epigenetic regulatory DNA elements that participate in the formation of chromatin boundaries and augment transcription, may mediate increased plasmid integration into the genome of CHO cells by stimulating DNA recombination. In the present work, we demonstrate that MAR-mediated plasmid integration results from the enhanced SD-MMEJ pathway. Analysis of transgene integration loci and junction DNA sequences validated the prevalent use of this pathway by the MAR elements to target plasmid DNA into gene-rich areas of the CHO genome. We propose that this finding should in the future help to engineer cells for improved recombinant protein production. In addition to investigating the process of transgene integration, we designed recombination assays to better characterize the components of the MMEJ and SD-MMEJ pathways. We also used CHO cells expressing cycle-sensitive reporter genes to demonstrate a potential role of HR proteins in the cell cycle regulation.
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Gender inequalities remain an issue in our society and particularly in the workplace. Several factors can explain this gender difference in top-level managerial positions such as career ambitions but also biases against women. In our chapter, we propose a model explaining why gender inequalities and particularly discrimination against women is still present in our societies despite social norms and existing legislation on gender equality. To this purpose, we review research on discrimination through two different approaches, (a) a prejudice approach through the justification-suppression model developed by Crandall and Eshleman (2003) and (b) a power approach through the social dominance theory (Pratto, Sidanius, Stallworth, & Malle, 1994; Sidanius & Pratto, 1999). In our work, we integrate these two approaches and propose a model of gender prejudice, power and discrimination. The integration of these two approaches contributes to a better understanding of how discrimination against women is formed and maintained over time.
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This review presents the evolution of steroid analytical techniques, including gas chromatography coupled to mass spectrometry (GC-MS), immunoassay (IA) and targeted liquid chromatography coupled to mass spectrometry (LC-MS), and it evaluates the potential of extended steroid profiles by a metabolomics-based approach, namely steroidomics. Steroids regulate essential biological functions including growth and reproduction, and perturbations of the steroid homeostasis can generate serious physiological issues; therefore, specific and sensitive methods have been developed to measure steroid concentrations. GC-MS measuring several steroids simultaneously was considered the first historical standard method for analysis. Steroids were then quantified by immunoassay, allowing a higher throughput; however, major drawbacks included the measurement of a single compound instead of a panel and cross-reactivity reactions. Targeted LC-MS methods with selected reaction monitoring (SRM) were then introduced for quantifying a small steroid subset without the problems of cross-reactivity. The next step was the integration of metabolomic approaches in the context of steroid analyses. As metabolomics tends to identify and quantify all the metabolites (i.e., the metabolome) in a specific system, appropriate strategies were proposed for discovering new biomarkers. Steroidomics, defined as the untargeted analysis of the steroid content in a sample, was implemented in several fields, including doping analysis, clinical studies, in vivo or in vitro toxicology assays, and more. This review discusses the current analytical methods for assessing steroid changes and compares them to steroidomics. Steroids, their pathways, their implications in diseases and the biological matrices in which they are analysed will first be described. Then, the different analytical strategies will be presented with a focus on their ability to obtain relevant information on the steroid pattern. The future technical requirements for improving steroid analysis will also be presented.
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Cysteine cathepsin protease activity is frequently dysregulated in the context of neoplastic transformation. Increased activity and aberrant localization of proteases within the tumour microenvironment have a potent role in driving cancer progression, proliferation, invasion and metastasis. Recent studies have also uncovered functions for cathepsins in the suppression of the response to therapeutic intervention in various malignancies. However, cathepsins can be either tumour promoting or tumour suppressive depending on the context, which emphasizes the importance of rigorous in vivo analyses to ascertain function. Here, we review the basic research and clinical findings that underlie the roles of cathepsins in cancer, and provide a roadmap for the rational integration of cathepsin-targeting agents into clinical treatment.
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A number of recent papers have brought suggestive evidence for an active role of Chlamydiales in the establishment of the plastid. Chlamydiales define a very ancient group of obligate intracellular bacterial pathogens that multiply in vesicles within eukaryotic phagotrophic host cells such as animals, amoebae or other protists, possibly including the hypothetical phagotroph that internalized the cyanobacterial ancestor of the plastid over a billion years ago. We briefly survey the case for an active role of these ancient pathogens in plastid endosymbiosis. We argue that a good understanding of the Chlamydiales infection cycle and diversity may help to shed light on the process of metabolic integration of the evolving plastid.
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Accurate perception of taste information is crucial for animal survival. In adult Drosophila, gustatory receptor neurons (GRNs) perceive chemical stimuli of one specific gustatory modality associated with a stereotyped behavioural response, such as aversion or attraction. We show that GRNs of Drosophila larvae employ a surprisingly different mode of gustatory information coding. Using a novel method for calcium imaging in the larval gustatory system, we identify a multimodal GRN that responds to chemicals of different taste modalities with opposing valence, such as sweet sucrose and bitter denatonium, reliant on different sensory receptors. This multimodal neuron is essential for bitter compound avoidance, and its artificial activation is sufficient to mediate aversion. However, the neuron is also essential for the integration of taste blends. Our findings support a model for taste coding in larvae, in which distinct receptor proteins mediate different responses within the same, multimodal GRN.
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The secondary thickening of plant organs in extant dicotyledons is a massive growth process that constitutes the major carbon sink in perennial, woody plants. Yet, our understanding of its molecular genetic control has been mostly obtained by its analysis in an herbaceous annual model, Arabidopsis. Recent years have seen increased interest in this somewhat under-researched topic, and various (non-)cell autonomous factors that guide the extent and vascular patterning of secondary growth have been identified. Concomitantly, a more detailed understanding of vascular differentiation processes has been obtained through analyses of primary growth, mostly in the root meristem. A future challenge will be the integration of these patterning and differentiation modules together with cambial activity into the 4-dimensional frame of secondary thickening.