266 resultados para LIE GROUP BUNDLES


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PURPOSE: The aim of this study was to evaluate the direct effect of surgical treatment of subfoveolar neovascular membranes in age related macular degeneration to macular functions. PATIENTS AND METHODS: Thirteen eyes of 13 patients were included in this study. Macular function was assayed by visual acuity and central visual field using the Octopus perimeter before surgery and in the first three post operative months. Pre and post operative fluorescein angiography frames were digitalized and the size of each lesions were compared. RESULTS: After a 3 months follow up, visual acuity remained stable or improved in 66% of the patients. However, visual acuity was better than 0.1 in 15% of the patients. Central visual field comparison disclosed a significant worsening of the retinal sensitivity in the 3 degree field surrounding the central point. On fluorescein frames, submacular scar was 141% of the size of the neovascular membrane. After a mean follow up of 6.9 months (range 3-14), one case of recurrence occurred. A cataract was observed in 85% of the phakic patients followed for more than six months. CONCLUSION: After a short term follow up, surgery can stabilise visual acuity, even though it remains poor. A worsening of the scotoma in the 3 degrees surrounding the central point is observed. However, patients noticed a subjective visual improvement in 62% of the case.

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This paper offers a reflection on the family life and that of the siblings of a child with cancer. We will present our intervention model developed jointly by the pediatric oncology and the pediatric psychiatry units at the University Hospital CHUV in Lausanne. It is known that siblings show difficulties in dealing with the ambivalent emotions triggered by the sickness of a brother or sister. Their defence mechanisms can be heavy and may have consequences on the child's psycho-affective development and on the dynamics of the whole family. Speech groups allow the siblings to unfold an experience which is often irrepresentable. They also permit remobilization of affects frozen by the illness. This model used since 2006 in our unit responds to the wish to improve the quality of care of heavily sick children.

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The 1st International Symposium on Ostracoda (ISO) was held in Naples (1963). The philosophy behind this symposium and the logical outcome of what is now known as the International Research Group on Ostracoda (IRGO) is here reviewed, namely ostracodology over the last 50 years is sociologically analysed. Three different and important historic moments for the scientific achievements of this domain are recognised. The first one, between about 1963-1983, is related to applied research for the oil industry as well as to the great interest in the better description of the marine environment by both zoologists and palaeontologists. Another important aspect during this period was the work by researchers dealing with Palaeozoic ostracods, who had their own discussion group, IRGPO. Gradually, the merger of this latter group with those dealing with post-Palaeozoic ostracods at various meetings improved communication between the two groups of specialists. A second period was approximately delineated between 1983 and 2003. During this time-slice, more emphasis was addressed to environmental research with topics such as the study of global events and long-term climate change. Ostracodologists profited also from the research "politics" within national and international programmes. Large international research teams emerged using new research methods. During the third period (2003-2013), communication and collaborative research reached a global dimension. Amongst the topics of research we cite the reconstruction of palaeoclimate using transfer functions, the building of large datasets of ostracod distributions for regional and intercontinental studies, and the implementation of actions that should lead to taxonomic harmonisation. Projects within which molecular biological techniques are routinely used, combined with sophisticated morphological information, expanded now in their importance. The documentation of the ostracod description improved through new techniques to visualise morphological details, which stimulated also communication between ostracodologists. Efforts of making available ostracod information through newsletters and electronic media are evoked.

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Background: EATL is a rare subtype of peripheral T-cell lymphomas characterized by primarily intestinal localization and a frequent association with celiac disease. The prognosis is considered to be poor with conventional chemotherapy. Limited data is available on the efficacy of ASCT in this lymphoma subtype. Primary objective: was to study the outcome of ASCT as a consolidation or salvage strategy for EATL. The primary endpoint was overall survival (OS) and progression-free survival (PFS). Eligible patients were > 18 years who had received ASCT between 2000-2010 for EATL that was confirmed by review of written histopathology reports, and had sufficient information on disease history and follow-up available. The search strategy used the EBMT database to identify patients potentially fulfilling the eligibility criteria. An additional questionnaire was sent to individual transplant centres to confirm histological diagnosis (histopathology report or pathology review) as well as updated follow-up data. Patients and transplant characteristics were compared between groups using X2 test or Fisher's exact test for categorical variables and t-test or Mann-Whiney U-test for continuous variables. OS and PFS were estimated using the Kaplan-Meier product-limit estimate and compared by the log-rank test. Estimates for non-relapse mortality (NRM) and relapse or progression were calculated using cumulative incidence rates to accommodate competing risk and compared to Gray's test. Results: Altogether 138 patients were identified. Updated follow-up data was received from 74 patients (54 %) and histology report from 54 patients (39 %). In ten patients the diagnosis of EATL could not be adequately verified. Thus the final analysis included 44. There were 24 males and 20 females with a median age of 56 (35-72) years at the time of transplant. Twenty-five patients (57 %) had a history of celiac disease. Disease stage was I in nine patients (21 %), II in 14 patients (33 %) and IV in 19 patients (45 %). Twenty-four patients (55 %) were in the first CR or PR at the time of transplant. BEAM was used as a high-dose regimen in 36 patients (82 %) and all patients received peripheral blood grafts. The median follow-up for survivors was 46 (2-108) months from ASCT. Three patients died early from transplant-related reasons translating into a 2-year non-relapse mortality of 7 %. Relapse incidence at 4 years after ASCT was 39 %, with no events occurring beyond 2.5 years after ASCT. PFS and OS were 54 % and 59 % at four years, respectively. There was a trend for better OS in patients transplanted in the first CR or PR compared to more advanced disease status (70 % vs. 43 %, p=0.053). Of note, patients with a history of celiac disease had superior PFS (70 % vs. 35 %, p=0.02) and OS (70 % vs. 45 %, p=0.052) whilst age, gender, disease stage, B-symptoms at diagnosis or high-dose regimen were not associated with OS or PFS. Conclusions: This study shows for the first time in a larger patient sample that ASCT is feasible in selected patients with EATL and can yield durable disease control in a significant proportion of the patients. Patients transplanted in first CR or PR appear to do better than those transplanted later. ASCT should be considered in EATL patients responding to initial therapy.

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Sensory information is an important factor in shaping neuronal circuits during development and adulthood. In the barrel cortex of adult rodents, cells from layer IV are able to adapt their functional state to an increased flow of sensory information from the mystacial whisker follicles. Previous studies in our group have shown that whisker stimulation induces the formation of inhibitory synapses in the corresponding barrel (Knott et al., 2002) and decreases neuronal responses toward the deflection of the stimulated whisker (Quairiaux et al., 2007). Together these observations have turned the barrel cortex into a model to study homeostatic plasticity. At the cellular level, neuronal activity triggers intracellular signaling cascades leading to a transcriptional response. To further characterize the molecular pathways involved in the synaptic changes after whisker stimulation in the adult mouse, a previous doctoral student in our group performed a microarray analysis on laser-dissected barrels in sections through layer IV. This study identified the regulation (up and down) of a series of genes in the stimulated barrels (thesis of Johnston-Wenger, 2010). We here focused on ten genes that presented the highest fold change according to the microarray analysis. Out of these genes, 7 are known as neuronal activity-dependent genes (Tnncl, Nptx2, Sorcs3, Ptgs2, Nr4a2, Npas4 and Adcyapl) whereas three have so far not been related to neuronal plasticity (Scn7a, Pcdhl5 and Cede3). The study aimed at confirming the results of the microarray analysis and localizing molecular modifications in the stimulated barrel column at the cellular level. In situ hybridization for Pcdhl5 after different periods of whisker stimulation (3, 6, 9, 15, 24 hrs) allowed us to confirm that the 1.25 fold change used for the microarray analysis is an appropriate threshold for considering a regulation significant after sensory-stimulation. Moreover, we confirmed with in situ hybridization a significant upregulation of the genes of interest in the stimulated barrels. In situ hybridization and immunohistochemistry allowed us to observe the distribution of the genes of interest and the corresponding protein products at the cellular level. Three observations were made: 1) alterations of the expression was restricted to the stimulated barrels for all genes tested; 2) within a barrel column not all cells responded to whisker stimulation with an altered gene expression; 3) in the stimulated barrels, two different patterns of mRNA and protein expression can be distinguished. We hypothesize that this segregation of the activity-induced gene expression reflects the segregation of the two principal thalamocortical pathways conveying the sensory information to the barrel cortex. Moreover, only neurons reaching the critical threshold will modify their gene expression program resulting in structural as well as physiological modifications that prevent the subsequent propagation of the excess of excitation to the postsynaptic targets. The activity-induced gene expression is therefore adapted in a cell-type-specific manner to induce a homeostatic response to the entire neuronal network involved in the integration of the sensory information. This to our knowledge the first study showing the distinct, but complementary contribution of the two thalamocortical pathways in experience-dependent plasticity in the adult mouse barrel cortex. -- L'information sensorielle nous permet de continuellement façonner nos circuits neuronaux autant durant le développement qu'à l'âge adulte. Chez le rongeur l'information sensorielle perçue par les vibrisses est intégrée au niveau du cortex somatosensoriel primaire (appelé en anglais « barrel cortex ») dont les cellules de la couche IV sont capables d'adapter leur état fonctionnel en réponse à une augmentation d'activité neuronale. Ce modèle expérimental a permis à notre groupe de recherche d'observer des changements rapides du circuit neuronal en fonction de l'activité sensorielle. En effet, la stimulation continue d'une vibrisse d'une souris adulte pendant 24 heures induit non seulement un remaniement synaptique (Knott et al., 2002), mais également des changements physiologiques au niveau des neurones du tonneau correspondant (Quairiaux et al., 2007). Ces observations nous permettent d'affirmer que le « barrel cortex » est un modèle approprié pour y étudier la plasticité synaptique. Au niveau cellulaire, l'activité neuronale déclenche des cascades de signalisation intracellulaire résultant en une réponse transcriptionnelle. Afin de caractériser les voies moléculaires impliquées dans la plasticité synaptique, une puce à ARN nous a permis de comparer l'expression de gènes entre un tonneau correspondant à une vibrisse stimulée et un tonneau d'une vibrisse non-stimulée (Nathalie). Cette analyse a révélé un certain nombre de gènes régulés de manière positive ou négative par l'augmentation de l'activité neuronale. Nous nous sommes concentrés sur 10 gènes dont l'expression est fortement régulée. L'expression de sept d'entre eux a déjà été démontrée comme dépendante de l'activité neuronale (Tnncl, Nptx2, Sorcs3, Ptgs2, Nr4a2, Npas4 otAdcyapl) alors que l'expression des trois autres (Scn7a, Pcdhl5 et Cedei) n'a pour le moment pas encore été liée à la plasticité neuronale. Le but de cette thèse est de confirmer les résultats de la puce à ARN et de déterminer dans quel type cellulaire ces gènes sont exprimés. L'hybridation in situ pour le gène Pcdhl5, après différentes périodes de stimulation des vibrisses (3, 6, 9, 15 et 24 heures), nous a permis de confirmer que le seuil de 1.25x utilisé dans l'analyse de la puce à ARN est approprié pour considérer qu'un gène est régulé de manière significative par la stimulation sensorielle. Nous avons également pu confirmer à l'aide de cette technique que la stimulation sensorielle augmente significativement l'expression de ces dix gènes. L'expression de ces gènes au niveau cellulaire a été observée à l'aide des techniques d'hybridation in situ et d'immunohistochimie. Trois observations ont été faites : 1) la régulation de ces gènes est restreinte aux tonneaux correspondants aux vibrisses stimulées ; 2) au niveau d'une colonne corticale correspondant aux vibrisses stimulées, seules certaines cellules présentent une altération de leur expression génique ; 3) au niveau des tonneaux stimulés, deux profils d'expression d'ARNm et de protéines sont observés. Notre hypothèse est que cette distribution pourrait correspondre à la terminaison ségrégée des deux voies thalamocortical qui amènent l'information sensorielle dans le cortex cérébral. De plus, seul les neurones atteignant le seuil critique d'activation modifient leur expression génique en réponse à la stimulation sensorielle. Ces changements d'expression géniques vont permettre à la cellule de modifier ses propriétés structurales et physiologiques de manière a prevenir la propagation d'un excès d'activité neuronale au niveau de ses cibles postsynaptics. L'activité neuronale agit donc spécifiquement sur certains types cellulaires de maniere a induire une réponse homéostatique au niveau du réseau neuronal impliqué dans l'integration de l'information sensorielle. Nos travaux démontrent pour une première fois que les deux voies sensorielles contribuent d'une manière distincte et complémentaire à la plasticité corticale induite par un changement de l'activité sensorielle chez la souris adulte.

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Eusocial societies are traditionally characterized by a reproductive division of labor, an overlap of generations, and cooperative care of the breeders' young. Eusociality was once thought to occur only in termites, ants, and some bee and wasp species, but striking evolutionary convergences have recently become apparent between the societies of these insects and those of cooperatively breeding birds and mammals. These parallels have blurred distinctions between cooperative breeding and eusociality, leading to calls for either drastically restricting or expanding wage of these terms. We favor the latter approach. Cooperative breeding and eusociality are not discrete phenomena, but rather form a continuum of fundamentally similar social systems whose main differences lie in the distribution of lifetime reproductive success among group members. Therefore we propose to array vertebrate and invertebrate cooperative breeders along a common axis, representing a standardized measure of reproductive variance, and to drop such (loaded) terms as ''primitive'' and ''advanced'' eusociality. The terminology we propose unites all occurrences of alloparental helping of kin under a single theoretical umbrella (e.g., Hamilton's rule). Thus, cooperatively breeding vertebrates can be regarded as eusocial, just as eusocial inverbrates are cooperative breeders. We believe this integrated approach will foster potentially revealing cross-taxon comparisons, which are essential to understanding social evolution in birds, mammals, and in sects.

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The aim of this study is to provide a better understanding of the genetic relationships within the widespread and highly polymorphic group of African giant shrews (Crocidura olivieri group). We sequenced 769 base pairs (bp) of the mitochondrial cytochrome b gene and 472 bp of the mitochondrial control region over the entire geographic range from South Africa to Morocco. The analyses reveal four main clades associated with different biomes. The largest clade occurs over a range covering Northwest and Central Africa and includes samples of C. fulvastra, C. olivieri, and C. viaria. The second clade is composed of C. goliath from Gabon, while South African C. flavescens, and C. hirta form two additional clades. On the basis of these results, the validity of some taxa in the C. olivieri group should be re-evaluated.

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Résumé Etant une importante source d'énergie, les plantes sont constamment attaquées par des pathogènes. Ne pouvant se mouvoir, elles ont développé des systèmes de défense sophistiqués afin de lutter contre ces prédateurs. Parmi ces systèmes, les voies de signalisation mettant en jeu des éliciteurs endog8nes tels que les jasmonates permettent d'induire la production de protéines de défense telles que les protéines dites "liées à la pathogénèse". Les gènes codant pour ces protéines appartiennent à des familles multigéniques. Le premier but de cette thèse est d'évaluer le nombre de ces gènes dans le génome d'Arabidopsis thaliana et d'estimer la part de ce système de défense, dépendant de la voie de signalisation des jasmonates. Nous avons défini un cluster de seulement 1S gènes sur 266, "liés à la pathogénèse", exclusivement régulés par les jasmonates. De multiples membres des familles des lectines de type jacaline et des inhibiteurs de trypsines semblent dépendre du jasmonate. Présente dans tous les systèmes immunitaires des eucaryotes, la famille des défensines est une famille très intéressante. Chez Arabidopsis thaliana, 317 protéines similaires aux défensines ont été définies, cependant seulement 15 défensines (PDF) sont bien annotées. Ces 15 défensines sont séparées en deux groupes dont un semble avoir évolué plus récemment. Le second but de cette thèse est d'étudier ce groupe de défensines à l'aide de la bioinformatique et des techniques de biologie moléculaire (gêne rapporteur, PCR en temps réel). Nous avons montré que ce groupe contenait une défensine acide intéressante, PDF1.5, qui semblait avoir subi une sélection positive. Cette protéine n'avait encore jamais été étudiée. Contrairement à ce que nous pensions, nous avons établi que cette protéine pouvait avoir une activité biologique liée à la défense. Ce travail de thèse a permis de préciser le nombre de gènes "liées à la pathogénèse" induits par la voie des jasmonates et d'apporter des éléments de réponse sur la question de la redondance des gènes de défense. En conclusion, même si de nombreuses familles de gènes intervenant dans la défense sont bien définies chez Arabidopsis, il reste encore de nombreuses études à faire sur chacun de ces membres. Abstract Being an important source of energy, plants are constantly attacked by herbivores and pathogens. As sessile organisms, they have developed sophisticated defense responses to cope with attack. Among these responses, signalling pathways, using endogenous elicitors including jasmonates (JA), allow the plant to induce the production of defense proteins such as pathogenesis-related (PR) proteins. The genes encoding these proteins belong to multigenic families. The first goal of this thesis was to evaluate the number of PR genes in the genome of Arabidopsis thaliana and estimate how much of this plant defense system was dependent on the jasmonate signaling pathway in leaves. Surprisingly a cluster of only 1S genes out of 2ó6 PR genes was exclusively regulated by JA. Multiple members of the jacalin lectin and trypsin inhibitor gene families were shown to be regulated by JA. Present in all eukaryotic immune systems, defensins are an attractive PR family to study. In Arabidopsis thaliana, 317 defensin-related proteins have been found but just 1S defensins (i.e. PDF family) are well annotated. These defensins are split into 2 groups. One of these groups may have appeared and diversified recently. The second goal of this thesis was to study this defensin gene group combining bioinformatic, reporter gene and quantitative PCR techniques. We have shown that this group contains an interesting acidic defensin, PDF1.S, which seems to have undergone positive selection. No information was known on this protein. We have established that this protein may have a biological activity in plant defense. This thesis allowed us to define the number of PR genes induced by the jasmonate pathway and gave initial leads to explain the redundancy of the PR genes in the genome of Arabidopsis. In conclusion, even if many defense gene families are already defined in the Arabidopsis genome, much work remains to be done on individual members.

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Intraspecific coalitional aggression between groups of individuals is a widespread trait in the animal world. It occurs in invertebrates and vertebrates, and is prevalent in humans. What are the conditions under which coalitional aggression evolves in natural populations? In this article, I develop a mathematical model delineating conditions where natural selection can favor the coevolution of belligerence and bravery between small-scale societies. Belligerence increases an actor's group probability of trying to conquer another group and bravery increase the actors's group probability of defeating an attacked group. The model takes into account two different types of demographic scenarios that may lead to the coevolution of belligerence and bravery. Under the first, the fitness benefits driving the coevolution of belligerence and bravery come through the repopulation of defeated groups by fission of victorious ones. Under the second demographic scenario, the fitness benefits come through a temporary increase in the local carrying capacity of victorious groups, after transfer of resources from defeated groups to victorious ones. The analysis of the model suggests that the selective pressures on belligerence and bravery are stronger when defeated groups can be repopulated by victorious ones. The analysis also suggests that, depending on the shape of the contest success function, costly bravery can evolve in groups of any size.

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This study examined the validity and reliability of a sequential "Run-Bike-Run" test (RBR) in age-group triathletes. Eight Olympic distance (OD) specialists (age 30.0 ± 2.0 years, mass 75.6 ± 1.6 kg, run VO2max 63.8 ± 1.9 ml· kg(-1)· min(-1), cycle VO2peak 56.7 ± 5.1 ml· kg(-1)· min(-1)) performed four trials over 10 days. Trial 1 (TRVO2max) was an incremental treadmill running test. Trials 2 and 3 (RBR1 and RBR2) involved: 1) a 7-min run at 15 km· h(-1) (R1) plus a 1-min transition to 2) cycling to fatigue (2 W· kg(-1) body mass then 30 W each 3 min); 3) 10-min cycling at 3 W· kg(-1) (Bsubmax); another 1-min transition and 4) a second 7-min run at 15 km· h(-1) (R2). Trial 4 (TT) was a 30-min cycle - 20-min run time trial. No significant differences in absolute oxygen uptake (VO2), heart rate (HR), or blood lactate concentration ([BLA]) were evidenced between RBR1 and RBR2. For all measured physiological variables, the limits of agreement were similar, and the mean differences were physiologically unimportant, between trials. Low levels of test-retest error (i.e. ICC <0.8, CV<10%) were observed for most (logged) measurements. However [BLA] post R1 (ICC 0.87, CV 25.1%), [BLA] post Bsubmax (ICC 0.99, CV 16.31) and [BLA] post R2 (ICC 0.51, CV 22.9%) were least reliable. These error ranges may help coaches detect real changes in training status over time. Moreover, RBR test variables can be used to predict discipline specific and overall TT performance. Cycle VO2peak, cycle peak power output, and the change between R1 and R2 (deltaR1R2) in [BLA] were most highly related to overall TT distance (r = 0.89, p < 0. 01; r = 0.94, p < 0.02; r = 0.86, p < 0.05, respectively). The percentage of TR VO2max at 15 km· h(-1), and deltaR1R2 HR, were also related to run TT distance (r = -0.83 and 0.86, both p < 0.05).