Some climate models are still lacking features such as dynamical modelling of ice sheets due to their computational cost which results in poor accuracy and estimates of e.g. sea level rise. The need for low-cost high-order models initiated the development of the First-Order Stokes (or Blatter-Pattyn) model which retains much of the accuracy of the full-Stokes model but is also cost-effective. This model has proven accurate for ice sheets and glaciers with frozen bedrocks, or no-slip basal boundary conditions. However, experimental evidence seems to be lacking regarding its accuracy under sliding, or stress-free, bedrock conditions (ice-shelf conditions). Hence, it became of interest to investigate this. Numerical experiments were set up by formulating the first-order Stokes equations as a variational finite element problem, followed by implementing them using the open-source FEniCS framework. Two types of geometries were used with both no-slip and slip basal boundary conditions. Specifically, experiments B and D from the Ice Sheet Model Intercomparison Project for Higher-Order ice sheet Models (ISMIP-HOM) were used to benchmark the model. Local model errors were investigated and a convergence analysis was performed for both experiments. The results yielded an inherent model error of about 0.06% for ISMIP-HOM B and 0.006% for ISMIPHOM D, mostly relating to the different types of geometries used. Errors in stress-free regions were greater and varied on the order of 1%. This was deemed fairly accurate, and probably enough justification to replace models such as the Shallow Shelf Approximation with the First-Order Stokes model in some regions. However, more rigorous tests with real-world geometries may be warranted. Also noteworthy were inconsistent results in the vertical velocity under slippery conditions (ISMIPHOM D) which could either be due to coding errors or an inherent problem with the decoupling of the horizontal and vertical velocities of the First-Order Stokes model. This should be further investigated. / Vissa klimatmodeller saknar fortfarande funktioner så som dynamisk modellering av istäcken på grund av dess höga beräkningskostnad, vilket resulterar låg noggrannhet och uppskattningar av t.ex. havsnivåhöjning. Behovet av enkla modeller med hög noggrannhet satte igång utvecklingen av den s.k. Första Ordningens Stokes (eller Blatter-Pattyn) modellen. Denna modell behåller mycket av noggrannheten i den mer exakta full-Stokes-modellen men är också väldigt kostnadseffektiv. Denna modell har visat sig vara noggrann för istäcken och glaciärer med frusna berggrunder eller s.k. no-slip randvillkor. Experimentella bevis tycks dock saknas med avseende på dess noggrannhet under glidning, eller stressfria, berggrundsförhållanden (t.ex. vid ishyllor). Därför ville vi undersöka detta. Numeriska experiment upprättades genom att formulera Blatter-Pattyn ekvatonerna som ett variationsproblem (via finita elementmetoden), följt av att implementera dem med hjälp av den öppna källkoden FEniCS. Två typer av geometrier användes med både glidande och stressfria basala randvillkor. Specifikt användes experiment B och D från Ice Sheet Model Intercomparison Project for Higher-Order ice sheet Models (ISMIP-HOM) för att testa modellen. Lokala fel undersöktes och en konvergensanalys utfördes för båda experimenten. Resultaten gav ett modellfel på ca 0,06 % för ISMIP-HOM B och 0,006 % för ISMIP-HOM D, vilka var mest relaterade till de olika typerna av geometrier som användes. Fel i stressfria regioner var större och varierade i storleksordningen 1 %. Detta ansågs vara ganska noggrant och sannolikt tillräckligt för att ersätta modeller så som Shallow Shelf Approximationen med Blatter-Pattyn-modellen i vissa regioner. Dock krävs mer noggranna tester med mer verkliga geometrier för att dra konkreta slutsatser. Också anmärkningsvärt var motsägande resultat i den vertikala hastigheten under glidande förhållanden (ISMIP-HOM D) som antingen kan ha berott på kodningsfel eller ett modelproblem som härstammar utifrån särkopplingen mellan den horizontella- och den vertikala hastigheten i Blatter-Pattyn-modellen. Detta bör undersökas vidare.

Les ganglions de la base (GB) sont des structures cérébrales profondes participant à la sélection de comportements adaptés, avec ses composantes motrices, cognitives et émotionnelles. L’étude par IRMf BOLD de ces structures présente un grand intérêt pour explorer leur rôle et leur dysfonctionnement dans certaines pathologies, comme la maladie de Parkinson (MP). Cette technique permet, par l’étude du signal BOLD, de mettre en évidence des activations cérébrales suite à une activation neuronale. Or l’IRMf BOLD a été optimisée pour l’étude des activations corticales, et la mise en évidence d’activations dans les GB est difficile, surtout au niveau individuel. Ceci est en parti lié au fait que le signal BOLD est plus faible dans ces structures par rapport au cortex. Plusieurs raisons peuvent expliquer ce faible signal BOLD. Ainsi la charge en fer de ses structures, modifiant le paramètre de relaxation T 2 *, peut en être une des causes. En effet, la sensibilité de mesure du signal BOLD est optimale lorsque le temps d’écho (TE) de la séquence d’acquisition égale le T 2 * de la structure cérébrale d’intérêt. Notre premier travail a consisté à étudier l’hétérogénéité du T 2 * dans différentes structures cérébrales en tenant compte des effets de la MP, pathologie connue pour entrainer des accumulations de fer dans certaines régions. Nous avons par ailleurs étudié l’évolution du T 2 * de manière longitudinale, et ce paramètre est apparu comme un biomarqueur intéressant de l’évolutivité de la MP. Le deuxième travail a été consacré à étudier les activations des GB en tenant compte de l’hétérogénéité du T 2 *. Nous avons étudié les activations cérébrales suite à la réalisation d’une tâche motrice, en explorant entre autres l’effet TE. Nous avons montré que le choix du TE a finalement peu d’impact sur la capacité de détection des activations au niveau des GB. Nous proposons une stratégie pour l’étude individuelle de l’activité cérébrale au niveau des GB en utilisant le pourcentage de changement du signal BOLD dans des régions cérébrales d’intérêt préalablement définies sur l’analyse de groupe. / The basal ganglia (BG) are deep brain structures involved in the selection of appropriate behavior, with motor, cognitive and emotional components. The BOLD fMRI study of these structures is of great interest to explore their role and dysfunction in certain diseases, such as Parkinson's disease (PD). By studying the BOLD signal, this technique allows to identify brain activation following neuronal activation. However BOLD fMRI has been optimized for the study of cortical activations and detection of activations in the BG is difficult, mainly at the individual level. This is partly due to the fact that the BOLD signal is lower in these structures in relation to the cortex. Several reasons may explain the BOLD signal attenuation. Thereby, iron load in its structures, which changes the relaxation parameter T 2 *, may be a cause. Indeed, the BOLD signal is optimal when the echo time (TE) of the MRI acquisition sequence equal T 2 * of the considered brain structure. Our first work was to study the heterogeneity of T 2 * in different brain structures, taking into account the effects of PD. Indeed, PD is known to induce iron accumulation some regions. We also studied the evolution of T 2 * longitudinally, and this parameter has emerged as an interesting biomarker to track PD progression. The second work was to study the activation of BG taking into account T 2 * heterogeneity. We studied brain activation during a motor task, exploring in particular the effect of TE. We showed that the choice of TE has a low impact on BG activation detection sensitivity. We propose a strategy for individual quantification of neuronal activity in the BG, using the BOLD percentage signal change in pre-defined regions of interest, obtained from the group analysis.

INTRODUÇÃO: o câncer de mama é uma doença heterogênea. Há necessidade de critérios diagnósticos e prognósticos mais refinados. O emprego da imunohistoquímica, através do painel prognóstico, fez despontar a figura do carcinoma triplonegativo e, da mesma forma, a histogenética trouxe à evidência o carcinoma basal. Paralelamente, o conhecimento sobre a origem biológica das neoplasias e da sua heterogeneidade vem sendo acentuadamente debatido através do tema das células-tronco tumorais. OBJETIVOS: investigar a prevalência de carcinomas basais e pentanegativos, numa amostra de carcinomas triplonegativos, e estabelecer associações com a expressão de células-tronco tumorais nestes tumores. Verificar diferenças entre estes subtipos com as variáveis clinicopatológicas. MÉTODOS: 94 carcinomas mamários triplonegativos foram testados para CK5/6, HER1, CD44 e CD24. As expressões desses marcadores por imuno-histoquímica automatizada foram avaliadas através de escore simples de positividade (porcentagem de células) e correlacionadas com os dados clínico-patológicos e análise de sobrevivência. RESULTADOS: carcinomas basais apresentam maior grau tumoral que carcinomas pentanegativos (p=0,004). A negatividade para CD44 (p=0,007) e o perfil CD44- CD24+ (p=0,013) foram associados com maior invasão vascular entre carcinomas triplonegativos. A expressão de CD44 foi associada aos carcinomas basais (p=0,007). O perfil CD44-CD24-/low foi associado aos carcinomas pentanegativos (p=0,04). Nenhuma das variáveis em estudo foi associada com os desfechos clínicos. CONCLUSÃO: Carcinomas mamários basais e pentanegativos são subtipos tumorais bastante próximos. Nosso estudo é o primeiro desenhado especificamente para avaliar a presença células tronco-tumorais mamárias entre carcinomas basais e pentanegativos, onde o perfil CD44-CD24-/low foi associado ao subtipo pentanegativo, e o perfil CD44-CD24+ à invasão vascular, resultados que merecem confirmação por histogenética em estudos de maior porte. / INTRODUCTION: Breast cancer is a heterogeneous disease, and there is a need for more refined diagnostic and prognostic criteria. Immunohistochemistry, as a breast prognostic panel, has given rise to triple-negative carcinoma, as well as histogenetics highlighted basal carcinoma. Concomitantly, the understanding of the biological origins of neoplasia and its heterogeneity has been strongly debated through the theme of cancer stem cells. OBJECTIVES: To investigate the prevalence of basal and penta-negative carcinomas in a sample of triple-negative carcinomas and to establish associations with cancer stem cells (CD44/CD24 expression profiles) and the clinicopathological variables within these tumors. METHODS: Ninety-four triplenegative breast carcinomas were tested for CK5/6, HER1, CD44 and CD24. The expression of these markers was evaluated by automated immunohistochemistry using a simple positivity score (percentage of cells) and was correlated with the clinicopathological and survival analysis data. RESULTS: Basal carcinomas had higher tumor grades than penta-negative carcinomas (p=0.004). CD44 negativity (p=0.007) and the CD44-CD24+ phenotype (p=0.013) were associated with increased vascular invasion amongst the triple-negative carcinomas. CD44 expression was associated with basal carcinomas (p=0.007). The CD44-CD24-/low phenotype was associated with penta-negative carcinomas. None of the variables in the study were associated with clinical outcome. CONCLUSION: Basal and penta-negative breast carcinomas are closely related tumor subtypes. Our study is the first to be specifically designed to assess the presence of breast cancer stem cells in basal and pentanegative carcinomas. The CD44-CD24-/low phenotype was associated with the pentanegative subtype, and the CD44-CD24+ phenotype was associated with vascular invasion. These results require histogenetic confirmation in larger studies.

Objetivo: O objetivo do presente estudo foi determinar o Gasto Energético Basal (GEB) através da Calorimetria Indireta (CI) em pacientes com carcinoma epidermóide de esôfago (CEE). Métodos: Estudo transversal com 30 pacientes internados com diagnóstico de CEE submetidos à CI antes de iniciar a terapia oncológica. A avaliação nutricional foi realizada a partir de parâmetros antropométricos (Índice de Massa Corporal, Circunferência do Braço, Dobra Cutânea Triciptal, Circunferência Muscular do Braço e Percentual de Perda de Peso), parâmetros bioquímicos (albumina, transferrina e Proteína C Reativa) e bioimpedância tetrapolar. Além disso, foram determinados a capacidade pulmonar e o estadiamento clínico. A CI foi realizada depois de uma noite de jejum. Valores de p < 0,05 foram considerados estatisticamente significativos. Resultados: A média do GEB pela CI foi de 1.421,8 ± 348,2 kcal e pela Equação de Harris e Benedict (EHB) de 1.310,6 ± 215,1 kcal. A EHB subestimou o GEB comparado com a CI (p= 0,014). Foi encontrada diferença significativa no GEB entre os pacientes desnutridos (1.181,7 ± 278,1 kcal) e bem nutridos (1.509,1 ± 334,1 kcal) pelo IMC (p=0,020). Pelo %PP não foram encontradas diferenças significativas entre o GEB dos pacientes com PP significativa e não significativa (p=0,526). Entre os pacientes que apresentavam o percentual de massa magra abaixo do esperado, foi encontrada GEB de 1.408,9 ± 364,3 kcal, enquanto que os que tinham o percentual de massa magra adequado o GEB foi de 1.538,4 ± 97,5 kcal (p=0,550). Não houve associação entre o GEB pela CI e o estadiamento (p=0,255) e o Índice de Tiffeneau (p=0,946). Na associação entre os exames laboratoriais e o GEB pela CI, não foram encontradas associações significativas entre os que tinham alteração e os que não a tinham (p= 0,364, 0,309 e 0,780, respectivamente). Conclusões: O GEB de pacientes com CEE foi subestimado pela EHB sem fator injúria e superestimado pela EHB com fator injúria de 1,3 quando comparado ao GEB medido pela CI. / Expenditure (BEE) of patients with squamous cell carcinoma (SCC) of the esophagus by indirect calorimetry (IC). Methods: Cross-sectional study involving 30 patients admitted with a diagnosis of SCC who underwent IC before starting cancer therapy. Nutritional assessment was conducted using anthropometric parameters (body mass index, arm circumference, triceps skinfold thickness, arm muscle circumference and percentage weight loss), biochemical parameters (albumin, transferrin and Creactive protein) and tetrapolar bioimpedance analysis. Additionally, lung capacity and clinical staging were determined. IC was carried out after overnight fasting. P values <0.05 were considered statistically significant. Results: The mean of the BEE for IC and Harris-Benedict equation were 1421.8 ± 348.2 kcal/day and 1310.6 ± 215.1 kcal/day, respectively. The HBE underestimated the BEE when compared with IC (p=0.014). A significant difference was found in the BEE between malnourished (1181.7 ± 278.1 kcal/day) and well-nourished (1509.1 ± 334.1 kcal/day) patients by BMI (p=0.020). In terms of percentage weight loss, no significant difference was found in BEE between patients with significant or non-significant weight loss (p=0.526). BEE for patients presenting with a lower than expected lean body mass was 1408.9 ± 364.3 kcal/day, whereas for those with an adequate lean body mass it was 1538.4 ± 97.5 kcal/day (p=0.550). No association was found between BEE measured by IC and clinical staging (p=0.255) or the Tiffeneau Index (p=0.946). Additionally, when comparing laboratory examinations with BEE measured by IC, no significant association was found between those with and those without alterations (p=0.364, 0.309 and 0.780 respectively). Conclusion: When compared to BEE measured by IC of patients with SCC, it was found that the HBE without injury factor underestimated, whereas the HBE with an injury factor of 1.3 overestimated BEE.

Purpose: Automatic border detection is the first and most crucial step for lesion segmentation and can be very challenging, due to several lesion characteristics. There are many melanoma border-detecting algorithms that perform poorly on dermoscopy images of basal cell carcinoma (BCC), which is the most common skin cancer. One of the reasons for poor lesion detection performance is that there are very few algorithms that detect BCC borders, because they are difficult to segment, even for dermatologists. This difficulty is due to low contrast, variation in lesion color and artifacts inside/outside the lesion. Segmentation that has adequate lesion-feature capture, with acceptable tolerance, will facilitate accurate feature segmentation, thereby maximizing classification accuracy. Methods: The main objective of this research was to develop an effective BCC border detecting algorithm whose accuracy is better than the existing melanoma border detectors that have been applied to BCCs. Fifteen auto-thresholding techniques were implemented for BCC lesion segmentation; but, only five were selected for use in algorithm development. A novel technique was developed to automatically expand BCC lesion borders, to completely circumscribe the lesion. Two error metrics were used that better measure Type II (false-negative) errors: Relative XOR error and Lesion Capture Ratio (a novel error metric). Results: On training and test sets of 1023 and 119 images, respectively, based on two error metrics, five thresholding-based algorithms outperformed two state-of-the-art melanoma segmentation techniques, in segmenting BCCs. Five algorithms generated borders that appreciably better matched dermatologists’ hand-drawn borders which were used as the “gold standard.” Conclusion: The five developed algorithms, which included solutions for image-vignetting correction and border expansion, to achieve dermatologist-like borders, provided more inclusive and therefore, feature-preserving border detection, favoring better BCC classification accuracy, for future work.

Les neuroblastomes olfactifs (NBOs) sont des tumeurs rares de la base du crâne. Les outils de classification de ces tumeurs sont insuffisants, il n’existe notamment aucune classification moléculaire des NBO. La biologie de ses tumeurs est mal connue. Nos travaux se sont appuyés sur l’analyse des exomes, du transcriptome, du méthylome et des caractéristiques histopathologiques et immunitaires d’une série de 59 NBOs bien annotés cliniquement. Nous avons mis en évidence l’existence de 2 sous-types de NBO présentant un profil d’expression et un profil anatomo-clinique différent. Le type neural, correspond à une tumeur bien différenciée, peu agressive, présentant des caractéristiques plutôt neuronales et partageant des caractéristiques phénotypiques avec les progéniteurs directs de neurones olfactifs. Le type basal correspond à une tumeur moins différenciée, plus agressive, ayant des caractéristiques plutôt embryonnaires, partageant des caractéristiques phénotypiques avec les cellules basales de renouvellement de l’épithélium olfactif. Nous avons mis en évidence que la charge mutationnelle était plus élevée dans le type basal, avec notamment des mutations IDH2 R172 récurrentes, associées à un phénotype CpG Island Methylator (CIMP). Nous avons également montré que les NBOs de type basal étaient infiltrés par un nombre plus important de lymphocytes T avec, dans certaines tumeurs, une expression plus marquée de checkpoints immunitaires et de facteurs immunosuppresseurs. Ce travail ouvre la perspective d’une classification moléculaire permettant de mieux stratifier les patients et ouvre également le champ de nouvelles stratégies thérapeutiques dans ces tumeurs rares. / Olfactory neuroblastomas (ONBs) are rare tumors arising in the skull base. Classification tools are poor, notably; no molecular classification of ONB has been reported. Literature data about their cell of origin, the existence of molecular therapeutic targets or their immune environment being scarce, the biology of these tumors is still poorly understood. Our work was based on exome, transcriptome and methylome analysis, but also on histopathological and immune characteristics of a series of 59 clinically well annotated ONBs. We highlighted 2 sub-types of ONB showing different expression and clinicopathologic patterns. The neural type is a well differentiated, poorly aggressive tumor which shows neurons characteristics and shares phenotypic similarities with olfactory neuron progenitors. The basal type is a less differentiated tumor, displaying an aggressive phenotype, with embryonic phenotypical characteristics, which shares similarities with basal renewing cells of the olfactory epithelium. We showed that the mutational load was higher in basal tumors, with notably recurrent IDH2 R172 mutations associated with a CpG Island Methylator Phenotype (CIMP). We also showed that basal type ONBs were infiltrated by a greater number of T cells with, in some cases, a higher expression of immune checkpoints and immunosuppressive factors. This work paves the way towards a new molecular classification which will allow a better stratification of patients and will open the field of new therapeutic strategies for this rare tumor.

Proteínas desacopladoras (UCPs) estão presentes na membrana mitocondrial interna e por meio do transporte de prótons do espaço intermembranas para a matriz mitocondrial desacoplam a oxidação dos substratos da síntese de ATP, dissipando a energia do potencial de membrana e, conseqüentemente, diminuindo a produção de ATP pela cadeia respiratória mitocondrial. O aumento na expressão de UCP2 está relacionado com um risco diminuído de obesidade e risco aumentado de desenvolvimento de diabetes melito. O polimorfismo - 866G/A na região promotora do gene da UCP2 está associado a um aumento da expressão do RNAm desta proteína. O objetivo do presente estudo foi avaliar o envolvimento do polimorfismo -866G/A no gene UCP2 nas respostas metabólicas ao exercício e na taxa metabólica basal em jovens saudáveis. Foram recrutados 27 homens com idades entre 20 e 35 anos, sem histórico de doenças e sem uso de medicamentos, eutróficos e que não estivessem envolvidos em nenhum tipo de treinamento físico. Os indivíduos foram alocados intencionalmente em três diferentes grupos, de acordo com o genótipo para o polimorfismo em questão: A/A(n=9), A/G (n=10) e G/G (n=8). Todos os indivíduos foram submetidos a uma análise de taxa metabólica basal e após uma refeição padrão realizavam 30 minutos de corrida em esteira em intensidade equivalente a 10% abaixo do 2º limiar ventilatório. Em jejum, antes do exercício, logo após realização do exercício, uma hora após e duas horas após o exercício foram realizadas coletas de sangue para a verificação do comportamento das concentrações de glicose, insulina e perfil lipídico. Não foram encontradas diferenças entre as respostas dos três grupos. Este estudo concluiu que isoladamente o polimorfismo -866G/A não exerce influência sobre a TMB e respostas de glicose, insulina e perfil lipídico ao exercício em jovens saudáveis. / Uncoupling proteins (UCPs) are present in the inner mitochondrial membrane and through the transport of protons from the intermembrane space to the mitochondrial matrix to uncouple oxidation of substrates for ATP synthesis, dissipating the energy of the membrane potential and, consequently, decreasing the production of ATP by the mitochondrial respiratory chain. The increased expression of UCP2 is associated with a decreased risk of obesity and increased risk of developing diabetes mellitus. The polymorphism -866G/A in the promoter region of the UCP2 gene is associated with an increased mRNA expression of this protein. The aim of this study was to evaluate the involvement of the polymorphism -866G/A UCP2 gene in the metabolic responses to exercise and basal metabolic rate (BMR) in healthy young adults. We recruited 27 men aged between 20 and 35 years without history of disease and drug treatment, eutrophic and that were not involved in any type of physical training. The individuals were placed intentionally in three different groups according to genotype for the polymorphism related above: A/A (n=9), A/G (n=10) and G/G (n=8). All subjects underwent an analysis of BMR and after a standard meal performed 30 minutes of treadmill running at an intensity equivalent to 10% below the 2nd ventilatory threshold. Fasting, before exercise, immediately after exercise, after one hour and two hours after exercise, blood samples were collected to verify the behavior of glucose, insulin and lipid profile. No differences were found between the responses of the three groups. This study concluded that the polymorphism -866G/A in an isolated way does not influence BMR and responses of glucose, insulin and lipid profile over exercise in young healthy men.

Os teleósteos são o grupo mais diversificado entre os vertebrados e seu registro mais antigo data do Jurássico. Sua atual classificação inclui quatro clados, dentre os quais Euteleostei é o mais avançado e variado. Apesar de todos os trabalhos a respeito do grupo, ele ainda não possui diagnose, definição e composição precisas. A discordância entre autores é ilustrada pelas nove diferentes propostas filogenéticas elaboradas nos últimos 30 anos. Muitos fósseis do Cretáceo são classificados como euteleósteos basais por falta de conhecimento morfológico, enquanto outros fósseis possuem classificação sistemática controversa ou compartilham aspectos estruturais com euteleósteos basais. Nesse contexto, os objetivos da presente dissertação são avaliar o monofiletismo de euteleósteos basais e recuperar relações filogenéticas de táxons do Nordeste do Brasil, África, Europa, Ásia e América do Norte atribuídos aos euteleósteos basais. Sete táxons brasileiros (i.e., Beurlenichthys ouricuriensis, Britoichthys marizalensis, Clupavus brasiliensis, Santanasalmo elegans, Santanichthys diasii, Scombroclupeoides scutata e novo euteleósteo da Bacia de Pelotas) e 14 táxons de localidades estrangeiras (i.e., Avitosmerus canadensis, Barcarenichthys joneti, Chanoides macropoma, Clupavus maroccanus, Gaudryella gaudryi, Humbertia operta, Kermichthys daguini, Leptolepides spratiiformis, Lusitanichthys characiformis, Nybelinoides brevis, Orthogonikleithrus leichi, Pattersonella formosa, Wenzichthys congolensis e Tchernovichthys exspectatum) foram analisados através de observação direta, fotografias, desenhos e descrições e submetidos a uma análise de Sistemática Filogenética utilizando o princípio da parcimônia. Três espécies recentes (i.e., Elops saurus, Hoplias malabaricus e Salmo trutta) foram usadas como grupo externo. Sessenta e dois caracteres foram selecionados e, como resultado, seis árvores igualmente parcimoniosas foram obtidas com 325 passos, índice de consistência (CI) de 0,2523 e índice de retenção (RI) de 0,4309. O consenso estrito é representado pela seguinte topologia: ((C. marocanus), (C. brasiliensis, (H. malabaricus + S. diasii))) ((G. gaudryi, (C. macropoma + L. characiformis)), (K. daguini), ((A. canadensis, (novo euteleósteo, (S. elegans + W. congolensis), (B. ouricuriensis + B. marizalensis)), (L. spratiiformis, (S. scutata, (N. brevis + P. formosa))), (B. joneti), (O. leichi), (H. operta + T. exspectatum), indicando que euteleósteos basais não formam um grupo monofilético e que as atuais sinapomorfias propostas são insuficientes para suportar o grupo. / Teleostei is the most diversified group among vertebrates and its oldest record dates from the Jurassic. It is currently divided into four clades, from which Euteleostei is the most derived and varied one. Despite all the studies on this group, precise diagnosis, definition, and composition are still lacking. The nine different phylogenetic hypotheses proposed in the last 30 years demonstrate the disagreement among authors. Several Cretaceous fossil fishes are assigned to basal euteleosteans due to the lack of morphological data, whereas some others possess a controversial taxonomic classification, and/or share anatomical features with basal euteleosteans. In this context, the goals of the present dissertation are to verify the monophyly of basal euteleosteans and to recover phylogenetic relationships within the taxa from Northeastern Brazil, Africa, Europe, Asia, and North America assigned to basal euteleosteans. Seven Brazilian taxa (i.e., Beurlenichthys ouricuriensis, Britoichthys marizalensis, Clupavus brasiliensis, Santanasalmo elegans, Santanichthys diasii, Scombroclupeoides scutata, and new euteleostean from the Pelotas Basin) and 14 from foregoing localities (i.e., Avitosmerus canadensis, Barcarenichthys joneti, Chanoides macropoma, Clupavus maroccanus, Gaudryella gaudryi, Humbertia operta, Kermichthys daguini, Leptolepides spratiiformis, Lusitanichthys characiformis, Nybelinoides brevis, Orthogonikleithrus leichi, Pattersonella formosa, Wenzichthys congolensis, and Tchernovichthys exspectatum) were analyzed by direct observation, as well as by means of photographs, drawings, and descriptions. After that, these taxa were submitted to a cladistic analysis using the principle of parsimony. Three living species (i.e., Elops saurus, Hoplias malabaricus, and Salmo trutta) were chosen to the outgroup. Sixtytwo characters were selected and, as a result, six equally parsimonious trees were obtained, with a length of 325 steps, consistency index (CI) of 0.2523, and retention index (RI) of 0.4309. The strict consensus tree is represented by the following topology: ((C. marocanus), (C. brasiliensis, (H. malabaricus + S. diasii))) ((G. gaudryi, (C. macropoma + L. characiformis)), (K. daguini), ((A. canadensis, (new euteleostean, (S. elegans + W. congolensis), (B. ouricuriensis + B. marizalensis)), (L. spratiiformis, (S. scutata, (N. brevis + P. formosa))), (B. joneti), (O. leichi), (H. operta + T. exspectatum), indicating that basal euteleosteans are not a monophyletic group and that the current synapomorphies are insufficient to support it.

Made available in DSpace on 2014-06-11T19:31:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-19Bitstream added on 2014-06-13T20:41:26Z : No. of bitstreams: 1 sampaio_rcl_dr_jabo.pdf: 2084812 bytes, checksum: 58460a9359272871dda4cd09bd01ae62 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / As alterações ultra-estruturais ocorridas nas lâminas epidérmicas e dérmicas de eqüinos com laminite são responsáveis pela rotação ou afundamento da falange distal dentro do casco. Com o objetivo de prevenir esta ocorrência foram estudados os efeitos da sobrecarga de carboidratos (SCHO), assim como da utilização de trinitroglicerina na fase prodrômica da laminite, nas lâminas epidérmicas do casco de quinze eqüinos. A indução da laminite por meio da sobrecarga de carboidratos alterou siginificativamente as lâminas epidérmicas primárias e secundárias dos cascos dos eqüinos dos grupos induzidos (Grupo Laminite e Grupo Laminite + Trinitroglicerina) em comparação com o Grupo Controle, causando retração das lâminas epidérmicas primárias, alongamento das lâminas epidérmicas secundárias e estreitamento das lâminas epidérmicas primárias e secundárias. A indução da laminite por meio da sobrecarga de carboidratos diminuiu significativamente a área da célula basal assim como a área do núcleo dos dois grupos induzidos (Grupo Laminite e Grupo Laminite + Trinitroglicerina) em comparação com o grupo controle. Foi observado, pela análise estatística, que o Grupo Laminite obteve maior redução das áreas, tanto da célula como do núcleo, porém a porcentagem de ocupação do núcleo na célula não foi diferente nos dois grupos induzidos. Na avaliação histopatológica, foram observadas lesões lamelares nos grupos Laminite e Laminite + Trinitroglicerina, características de processo degenerativo das lâminas epidérmicas. Ocorreram diminuições nos números de hemidesmossomos dos grupos induzidos quando comparados com o Grupo Controle. A administração de trinitroglicerina não foi capaz de impedir o desenvolvimento de lesões nas lâminas epidérmicas e dérmicas, assim como, nas células basais e membrana basal em cavalos com laminite induzida por sobrecarga de carboidratos. / Disruption of the lamellar ultrastructural is responsible for a cellular failure, that culminates in distal rotation of the distal phalanx within the hoof. Aiming to prevent such debilitating condition, effects of carbohydrate overload and glyceryl trinitrate (TNG) use during the prodromal stages of experimentally induced laminitis in fifteen horses hoof were studied. Laminitis induced by grain overload affected significantly primary and secondary lamellar structure from horse´s hoof (Group II and III), which in turn led to primary epidermal retraction, basal cells became elongated and both primary and secondary epidermal lamellae clump together when compared to control group (GI). Equine that developed laminitis induced by carbohydrate overload had a significant reduction in basal cell nucleus in both GII and GIII groups, when compared to horses from GI. Horses from GII group had higher reduction in areas relative to both cell and nucleus, however, the percentage of nucleus position within cell was not different in both horses groups (GII and GIII). Histophatology of hooves revealed lamellae lesions in both horses groups (GII and GIII), characterized by a degenerative process present on epidermal lamellae. Lower number of hemidesmosome in both GII and GIII groups were observed. The administration of TNG was unable to prevent the development of lesions lamellae epidermal and dermal, as in the epidermal basal cells and the basement membrane in horses with laminitis induced by carbohydrate overload.

Made available in DSpace on 2014-06-11T19:23:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T19:50:02Z : No. of bitstreams: 1 tavares_rlm_me_jabo.pdf: 1766165 bytes, checksum: 1586def62988001b88a6b492ab514b0c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A mineralização da matéria orgânica do solo pode ser compreendida como o processo de degradação de compostos orgânicos por resíduos de culturas e outros materiais orgânicos adicionados no solo. O efeito da mineralização em diferentes ecossistemas e tipos de solos é uma oportunidade para avaliar mudanças nas variáveis microbiológicas e químicas do solo. Nesse trabalho, foi avaliado o efeito da mineralização da matéria orgânica do solo em duas situações: experimento: (1) em diferentes ecossistemas e (2) - em dois solos adicionados de folha e caule de soja. Experimento 1- O objetivo desse trabalho foi quantificar a mineralização da matéria orgânica nos ecossistemas de floresta natural, pastagem e cultura anual na atividade microbiana do solo. As amostras de solo foram coletadas nas áreas de floresta, pastagem e cultura anual (milho), nas profundidades de 0 –10, 10 – 20 e 20 – 40 cm. O carbono da biomassa microbiana (CBM), atividade respiratória microbiana (ARM) e o potencial de nitrificação (PN) foram determinados. Carbono orgânico total (COT), carbono solúvel (CS), ácido húmico (AH) e fúlvico (AF) e a taxa de humificação (TH) e grau de humificação (GH) também foram determinados. O modelo estatístico usado foi o de parcelas subdvididas (fator 1: ecossistemas e fator 2: profundidade) com quatro repetições. No inverno, os teores de COT e CS foram maiores no solo de floresta que no de pastagem e cultura anual de acordo com a ordem: floresta>pastagem>cultura anual e no verão prevaleceu floresta=pastagem>cultura anual. Os teores de AH e AF variaram no inverno e verão de acordo com a ordem floresta>pastagem=cultura anual. O CBM no inverno não foi influenciado pelos ecossistemas e no verão apenas o ecossistema com cultura anual apresentou menor teor de CBM. A ARM foi maior no solo sob pastagem que em solo de floresta e cultura anual, porém... / Soil organic matter mineralization can be understood as a process of degradation of organic compounds from crop residues and other organic material added into the soil. The effect of mineralization in different ecosystems and soil types is an opportunity to assess changes in microbiological and chemical variables of soil. The effect of soil organic matter mineralization was evaluated in two experiments: (1) in different ecosystems; and (2) - in two soils added with leaves and stems of soybean. Experiment 1 – the objective of this study was to quantify the mineralization of organic matter from different ecosystems including natural forest, pasture and annual crop on soil microbial activity. Soil samples were collected from areas of forest, pasture and maize, at depths of 0 -10, 10 - 20 and 20 - 40 cm. The microbial biomass carbon (MBC) contents and the activities of microbial respiratory (MRA), potential nitrification (PN) were determined. Total organic carbon (TOC), dissoLVefd carbon (CS), humic acid (HA) and fulvic (FA) contents and humification rate (TH) and degree of humification (GH) were also determined. The statistical model used was a split plot (factor 1: ecosystem and factor 2: depth) with four replicates. In winter, the TOC and CS contents were higher in the forest soil than in the pasture and annual crop soil and decreased in the following order: forest> pasture> annual crop. in the summer, the relationship was the following: forest =pasture> annual crop. The HA and FA contents varied in winter and summer in the order forest>grassland=annual crop. The CBM content was not influenced by ecosystems in winter and in summer the lowest CBM amount was showed in annual crop. ARM was higher in pasture soil than in forest soil and annual crop, however, the NP was highest in forest soil. The chemical and biological attributes decreased with soil depth, except the rate and degree... (Complete abstract click electronic access below)