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Biologické a s biologií související koncepce agrese se zvláštním přihlédnutím k její hormonální regulaci. / Biological and related theories of aggression and its humoral regulationBradáč, Ondřej January 2013 (has links)
Aggression is a phenomenon which acquired a substantial share on attention of biological literature, especially since the beginning of 20th century. In this thesis, various approaches to the problem from the field of biology are summarized. Intensified attention is dedicated to the theoretical concepts of aggression, especially the concepts consulting the problem of aggression from the evolutionary point of view and to the research on the field of hormonal regulation of aggression, stressing out the role of the hormone testosterone, and to particular hypothesis, which take account on its mutual relationship with behavior. The empirical part of the thesis is dedicated to verification of premises of the challenge hypothesis according to the relationship between testosterone and aggressive behavior. Significant findings of the empirical part refer to the existence of a link between basal level of testosterone and aggressive tendencies and to the existence of a negative link between basal level of testosterone and its increase in reaction to a competitive situation.
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Využití bazální stimulace v předškolním vzdělávání / Use of basal stimulation in pre-school educationBechová, Veronika January 2013 (has links)
A dissertation "Use of basal stimulation in preschool education" has the aim to confirm a positive influence of the basal stimulation concept on upbringing and education of children with multiple disabilities in a special kindergarten. A theoretical part gives you a brief characteristic on the topic of multiple disabilities and cerebral palsy (CP). It brings you a view of the development of children with disabilities in the preschool period. A crucial part is dedicated to the basal stimulation concept as well as its basic and superstructural elements and biographical anamnesis. A research project presents the case studies and shows the use of the concept at particular work. It evaluates and confirms the positive influence of stimulation on children and presents a recommendation for pedagogical practice. Keywords: multiple disabilities, a child in the preschool education, basal stimulation
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Late Neogene Uplift of the Fairweather Ground on the Basis of Bathymetric and Seismic Data from the Gulf of AlaskaGuarisco, Peter David, IV 16 May 2008 (has links)
Pliocene to Pleistocene glacial-marine deposits adjacent to the Fairweather Ground basement in the Gulf of Alaska are the focus for seismic interpretation using public domain seismic reflection data. The late Tertiary and early Quaternary sections of the Yakataga Formation record a glacial/ interglacial climate change sequence with increasing rates of sedimentation (175 meters per million years to 4000 meters per million years). The foreland basin sediment load is deposited onto the Yakutat block, a microplate that takes up the strike-slip to convergent movement with respect to North America and Pacific plates. Tectonic activity during the last 5 million years has resulted in Eocene rock exposed at the sea floor. High resolution bathymetry data adjacent to the Yakutat microplate is utilized to 1) observe the results of deformation from Pacific plate loading on the Yakutat microplate and 2) interpret the Transition fault as an active thrust to oblique thrust fault.
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Modèle biomimétique à accumulateurs de la boucle Colliculo-Basale pour la sélection subcorticale des cibles des saccades oculaires / Biomimetic race model of the Tecto-Basal loop for the subcortical selection of ocular saccades targetsThurat, Charles 16 June 2014 (has links)
Le Colliculus Supérieur (SC) est bien connu pour son rôle dans la génération des saccades oculaires. Sa connectivité réciproque avec les Ganglions de la Base (BG) a récemment été mise en évidence, ainsi que son implication active dans les processus de sélection saccadique. Indépendamment du rôle des BG dans la sélection en général, les hypothèses traditionnelles suggèrent que la sélection au sein du SC résulte d'inhibitions latérales réciproques. Notre modèle propose de développer une autre hypothèse, dans laquelle les BG jouent un rôle important pour la sélection des cibles des saccades par un circuit purement sous-cortical SC-BG. En partant du constat que les profils d'activités des populations neuronales du SC peuvent être assimilés à ceux des neurones accumulateurs stochastiques des modèles phénoménologiques de sélection par course, ce nouveau modèle propose que la sélection observée dans le SC résulte non pas d'interactions latérales dans le SC, mais d'un processus de course vers un seuil de sélection dans les couches colliculaires intermédiaires, seuil dynamiquement déterminé par une désinhibition sélective opérée par les BG dans le cadre d'une boucle de rétrocontrôle double des BG vers le SC. Ce modèle reproduit divers profils d'activité neuronaux observés in-vivo, ainsi que les profils de sélection de plusieurs tâches expérimentales relatives à la discrimination entre de nombreux stimuli similaires. Son neuromimétisme lui permet de proposer diverses prédictions sur les substrats neurologiques de ses composants, et les substrats neurologiques de divers phénomènes particuliers de sélection comme les saccades moyennes ou le remote distractor effect. / The Superior Colliculus (SC) is well-known for its role in the generation of ocular saccades. Its reciprocal connectivity with the Basal Ganglia (BG) has recently been highligted, as well as its active involvement in the saccadic selection processes. Yet, the most common hypothesis explaining its role in saccade target selection neglect the potential implication of the BG and focus on unproven networks of lateral reciprocal inhibitions within the SC. We propose a model based on a the SC-BG loop hypothesis, in the framework of a purely subcortical saccade selection process Since the activity profiles of specific SC neurons populations can be seen as equivalent to the stochastic accumulators of the phenomelogical race models, we propose that the selection operated bythe SC is based not on lateral inhibitions within its maps, but on a race to a selection threshold in the intermediate layers of the SC, the threshold being dynamically set by the selective disinhibition of the SC maps by a double closed loops with the BG. Our model is able to reproduce various in-vivo neuronal activity profiles, as well as the selection distributions observed in various experimental setups involving the discrimination between numerous identical stimuli. Our model's neuromimetism level allows us to propose predictions about the neuronal substrates of the model's components, as well as the substrates for various selection phenomenons such as average saccades and the remote distractor effect.
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Identificação das proteínas interagentes de Yes-Associated protein (YAP), um efetor da via Hippo, em células epiteliais mamárias expostas à matriz extracelular rica em laminina / Identification of interacting proteins of Yes-Associated Protein (Yap) in mammary epithelial cells exposed to laminin-rich extracellular matrixManucci, Antonio Carlos 01 March 2019 (has links)
A sinalização da matriz extracelular (MEC) é essencial para a determinação do destino e comportamento de células epiteliais da glândula mamária. Entretanto, pouco é conhecido sobre os mecanismos moleculares envolvidos nesse processo. A via Hippo, uma cascata de sinalização que participa da regulação de diversos comportamentos celulares, incluindo o tamanho de órgãos, parece ser uma importante candidata a mediadora sinalização da MEC. Resultados preliminares do laboratório indicam que a arquitetura tecidual e a membrana basal, componente da MEC de epitélios e outros tecidos, influenciam a localização, concentração e atividade de YAP, uma proteína efetora da via Hippo, em células epiteliais mamárias. Neste contexto, o objetivo deste trabalho foi identificar as proteínas que interagem com Yap (ortólogo de YAP em camundongo) nas células epiteliais da glândula mamária em resposta à membrana basal. Foram utilizadas células EpH4, uma linhagem mamária não-tumoral murina, como modelo de diferenciação funcional e formação de ácinos em um ensaio de cultura tridimensional (3D). O tratamento de estruturas multicelulares 3D pré-formadas em placas nãoadesiva com uma matriz rica em laminina (lrECM) alterou a localização e o padrão subcelular de Yap, assim como a expressão gênica de membros da via Hippo e dos alvos de Yap, mas não alterou a expressão das proteínas da via em nível de proteína. O ensaio de co-imunoprecipitação (CoIP) seguida de análise por espectrometria de massas identificou um conjunto diferencial de proteínas que interagem com Yap na fração citoplasmática de células EpH4 cultivadas na ausência ou na presença de lrECM em um modelo de ECM-overlay. Uma análise realizada junto à database KEGG Pathways revelou que os possíveis interagentes Yap nas células cultivadas não-tratadas com lrECM participam de processos relacionados à proteólise mediada por ubiquitina, enquanto nas células expostas à lrECM os possíveis interagentes estão associados a processos metabólicos e são especialmente proteínas-chave do metabolismo de lipídios. A busca na plataforma de redes de interação STRING não identificou trabalhos que destaquem a interação de Yap com estas proteínas. A plataforma Vizit indica a participação de Yap em processos relacionados à síntese e atividade de lipídios e hormônios, o que reforça as evidências de que está pode ser uma nova função de Yap ainda não explorada em detalhes. A fim de se obter resultados complementares à CoIP, padronizamos o ensaio de identificação por biotinilação dependente de proximidade (BioID) em células embrionárias de rim humano da linhagem 293FT. As proteínas isoladas por pulldown foram identificadas por espectrometria de massas e uma análise junto à database Gene Ontology indicou que os possíveis interagentes de Yap nestas células são em sua maioria proteínas relacionadas à via Hippo, o que reforça a robustez do ensaio. Nós pretendemos transpor este sistema para as células EpH4. A expectativa é que, em conjunto, estes resultados nos orientem em projetos futuros para compreender os mecanismos de sinalização da MEC na morfogênese e diferenciação da glândula mamária. / Extracellular matrix (ECM)-signaling is crucial for determination of epithelial cell fate and behavior in the mammary gland. However, little is known about the molecular mechanisms involved in these processes. The Hippo pathway, a signaling cascade involved in the regulation of several cellular processes, including organ size, seems to be an important candidate as a mediator of this signaling. Our preliminary results indicate that the tissue architecture and the basement membrane, an ECM component of epithelia and other tissues, influence the location, level and activity of YAP, an effector of the Hippo pathway. In this context, the goal of this work was to identify the proteins that interact with Yap (ortholog of YAP in mouse) in mammary epithelial cells in response to the basement membrane. We used EpH4 cells, a nontumoral murine mammary cell, in a functional differentiation and acini-forming in tridimensional (3D) culture assay. Treatment of 3D multicellular structures pre-formed on nonadhesive plates with a laminin-rich extracellular matrix (lrECM) altered the subcellular localization and pattern of Yap, as well as gene expression of Hippo pathway proteins and Yap targets, but did not altered the expression of the pathway members at the protein level. Coimmunoprecipitation (CoIP) followed by mass spectrometry analysis identified a differential set of proteins interacting with Yap in cytoplasmic fractions of EpH4 cells in the absence or presence of lrECM in an ECM-overlay culture model. An analysis performed with the KEGG Pathways database revealed that putative Yap interactors in non-treated cells participate in processes related to ubiquitin-mediated proteolysis, whereas in cells exposed to lrECM Yap interactors are associated to metabolic processes and are mainly key-proteins of metabolism of lipids and carbohydrates. A search in interaction networks platform STRING did not identify previous works that showing the interaction of Yap with these proteins. Vizit platform indicated the participation of Yap in processes related to the synthesis and activity of lipids and hormones, which reinforces the evidences that Yap can play a novel poorly explored role. To obtain complementary results to CoIP, we devised the proximity-dependent biotinylation identification (BioID) assay on embryonic renal cells of 293FT cell line. Pulldown-isolated proteins were identified by mass spectrometry and an analysis performed with Gene Ontology database revealed that putative Yap interactors are Hippo pathway-related proteins, which reinforces the robustness of the assay. We intend to transpose this system to the EpH4 cells. We expect that, together, these results will guide us in future projects to understand the signaling mechanisms of ECM in mammary gland morphogenesis and differentiation.
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Synaptic plasticity emerging from chemical reactions : Modeling spike-timing dependent plasticity of basal ganglia neurons / Emergence de la plasticité synaptique à partir des réactions biochimiques : Modélisation de la plasticité dépendante du timing du potentiel d'action (STDP) des neurones des ganglions de la baseProkin, Ilia 02 December 2016 (has links)
Notre cerveau prend en charge différentes formes d’apprentissage dans ses diverses parties. C’est par exemple le cas des ganglions de la base, un ensemble de noyaux sous-corticaux qui est impliqué dans la sélection de l’action et une forme spécifique de l’apprentissage / mémoire, la mémoire procédurale (mémoire des compétences ou d’expertise). A l’échelle du neurone unique, le support le plus plausible de l’apprentissage et de la mémoire est la plasticité synaptique, le processus par lequel l’efficacité de la communication entre deux neurones change en réponse à un pattern spécifique de conditions environnementales. Parmi les différentes formes de plasticité synaptique, la plasticité dépendante du timing des spikes (STDP) représente le fait que le poids synaptique (l’efficacité de la connexion) change en fonction du temps écoulé entre l’émission des deux potentiels d’action (spikes) présynaptiques et postsynaptiques consécutifs. Si la STDP est une forme de plasticité qui a récemment attiré beaucoup d’intérêt, on ne comprend pas encore comment elle émerge des voies de signalisation / biochimiques qui la sous-tendent. Pour répondre à cette question, nous combinons les approches expérimentales de nos collaborateurs (pharmacologie et électrophysiologie) avec la modélisation de la dynamique des réseaux de signalisation impliquées (décrite par des équations différentielles ordinaires). Après estimation des paramètres, le modèle reproduit la quasi-totalité des données expérimentales, y compris la dépendance de la STDP envers le nombre stimulations pré- et post-synaptiques appariées et son exploration pharmacologique intensive (perturbation des voies de signalisation par des produits chimiques). En outre, contrairement à ce qui était largement admis dans la communauté des neurosciences, notre modèle indique directement que le système endocannabinoïde contrôle les changements du poids synaptique de façon bi-directionnelle (augmentation et diminution). De plus, nous étudions comment une série de facteurs comme la recapture du glutamate régule la STDP. Notre modèle représente une première étape pour l’élucidation de la régulation de l’apprentissage et de la mémoire au niveau du neurone unique dans les ganglions de la base. / Our brains support various forms of learning in their various subparts. This is for instance the case of the basal ganglia, a set of subcortical nuclei that is involved in action selection and a specific form of learning / memory, procedural memory (memory of skills or expertise). At the scale of single neurons, the most plausible support of learning and memory is synaptic plasticity, the process by which the efficiency of interneuronal communication changes in response to a pattern of environmental conditions. A recent focus of research is on spike-timing dependent plasticity (STDP), whereby the relative timing of activations (spikes) of connected pre- and postsynaptic neurons, determines the synaptic weight (the efficiency of synaptic connection). Notwithstanding, the dependence of STDP on underlying signaling pathways is not yet fully understood. To address this issue, we combine experimental approaches by our collaborators (pharmacology and electrophysiology) with modeling of the implicated signaling network (described by Ordinary-Differential Equations). After parameter estimation, the model reproduces much of experimental data, including the dependence of STDP on the number of paired stimuli of pre- and postsynaptic neurons and intensive pharmacological exploration (where signaling molecules are perturbed by chemicals). Furthermore, in opposition to what was widely believed in the neuroscience community, our model directly indicates that the endocannabinoid system supports bidirectional changes of the synaptic weight (increase and decrease). Moreover, we study how a range of factors including glutamate uptake regulates STDP. We expect our model to be a starting point to the elucidation of the regulation of learning and memory in the basal-ganglia at the single neuron level.
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Efeitos do envelhecimento sobre o sistema nitrérgico dos núcleos da base em humanos / Effects of aging over nitrergic system in human basal nucleiSantos, Bruno Lopes dos 22 April 2014 (has links)
O óxido nítrico (NO) é uma molécula gasosa descrita recentemente, com implicações sobre uma vasta quantidade de processos fisiológicos, incluindo transmissão de sinais no sistema nervoso central (SNC). A sinalização nervosa mediada pelo NO ocorre por meios extrassinápticos, na chamada neurotransmissão por volume. Há evidências de que o NO seja um importante fator de modulação no controle da motricidade. A presença de neurônios que produzem NO já foi descrita em várias espécies, e estruturas ligadas ao controle do movimento como os núcleos da base (NNBB) contêm células nitrérgicas em quantidades variadas. Não se conhece os efeitos do processo de envelhecimento sobre a estrutura e função destes neurônios produtores de NO. O objetivo geral deste estudo foi investigar se o envelhecimento provoca alterações nos neurônios nitrérgicos presentes nos NNBB do encéfalo humano. Além disso, busca agregar mais conhecimento a aspectos morfológicos e de distribuição das células que compõem o sistema nitrérgico nos NNBB em humanos. As amostras de estriado (caudado e putâmen), globos pálidos (GP), núcleo subtalâmico (NST), substância negra (SN) e núcleo pedunculopontino (NPP) de 20 indivíduos sem doenças neurológicas e psiquiátricas foram submetidas à avaliação histológica em secções, coradas por técnicas que localizam neurônios que expressam NO, como a histoquímica para NADPH-diaforase (NADPHd) e à imunohistoquímica para sintase do NO neuronal (nNOS), e parâmetros de densidade neuronal e morfometria foram comparados entre indivíduos adultos jovens e idosos. Análises de densidade neuronal e morfometria entre subdivisões topográficas e funcionais também foram realizadas. Foi visto que o envelhecimento não provoca modificações na densidade neuronal e morfometria nitrérgica nos NNBB em humanos. Adicionalmente, o trabalho mostrou que: (I) as regiões mais posteriores do estriado se destacaram por apresentarem uma elevada densidade neuronal, associada a neurônios menores, em comparação com as regiões mais anteriores; (II) as porções do estriado ligadas ao córtex límbico apresentam maiores densidades neuronais; (III) o NST é uma região em que cerca de 90% de seus neurônios expressam NO, e suas características morfológicas sugerem que estas células coexpressem glutamato; (IV) o NPP é extensamente povoado por neurônios nitrérgicos, principalmente no nível do colículo inferior; (V) a presença de células NO-positivas é preponderante nas lâminas medulares de ambos GP, porém notamos maior concentração de células nitrérgicas no GPi; (VI) não foi detectada presença de neurônios quem contém NO na SN. Nossos resultados mostram que há uma presença maciça de neurônios que expressam NO em núcleos-chaves envolvidos com processamento motor corticobasal, como o NST, o estriado e o NPP, sugerindo que a neurotransmissão nitrérgica seja peça fundamental da fisiologia dos NNBB, portanto, com considerável potencial terapêutico nas doenças que afetam estas estruturas. / The nitric oxide (NO) is a gaseous molecule recently described, with a role on several physiologic processes, including signal transmission in central nervous system (CNS). The NO-mediated brain signaling occurs by extrasynaptic mode, called volume transmission. There are evidences supporting the NO as a major neurotransmitter involved on motor control modulation. The presence of NO neurons was described in many species, and movement-related structures, as the basal nuclei (BN), also contains variable densities of nitrergic cells. It is unknown the effect of aging over the structure and function of these NO neurons. The objective of the study is to investigate if the aging causes abnormalities on human BN nitrergic neurons. Furthermore, we aimed to explore distribution and morphologic features of these cells in BN. The samples of striatum (caudate and putamen), globus pallidum (GP), subthalamic nucleus (STN), substantia nigra (SN) and pedunculopontine nucleus (PPN) of 20 human brains from subjects without neurologic or psychiatric disases were processed for histologic analysis, stained by 2 techniques which localizes NO neurons: histochemistry for NADPH-diaphorase (NADPHd) and immunohistochemistry for neuronal NO synthase (nNOS); the neuronal density and morphometric parameters were compared between young adults and aged subjects. The neuronal density and morphometric analysis between striatal and subthalamic topographic / functional subdivisions were also performed. Our data showed that aging does not change the neuronal density or morphometric parameters of nitrergic neurons in human BN. Additionally, other results were found: (I) the most posterior regions of striatum have a higher neuronal density and smaller neurons than the most anterior regions of this nucleus; (II) the limbic cortex-associated areas of striatum have higher neuronal density than others functional subdivisions; (III) the STN is a region in which about 90% of its neurons expresses NO, and its morphologic features suggest these neurons coexpress glutamate; (IV) the PPN has a massive nitrergic neuronal density, mostly in the inferior colliculus level; (V) in GP, there is a marked presence of NO neurons in laminae medullaris, and the internal GP has more NO-positive cells than the external GP; (VI) nitrergic neurons were not detected in SN. Our results showed a remarkable presence of neurons expressing NO in nuclei essential for motor corticobasal processing (striatum, STN, PPN), suggesting that the nitrergic neurotransmission has a fundamental role in BN physiology, therefore, with great therapeutic potential in diseases involving these structures.
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Caractérisation phénotypique, comportementale et neurochimique, de la souris mutante ataxique scrambler (Dab1scm) / Phenotypic, behavioral and neurochemical characterization of the mutant ataxic mice scrambler (Dab1scm)Jacquelin, Cécile 10 December 2015 (has links)
La souris scrambler (Dab1scm) est un mutant ataxique cérébelleux qui présente une mutation naturelle du gène mdab1, codant pour une protéine intracellulaire nécessaire à la voie de signalisation de la rééline. Cette protéine joue un rôle crucial dans la mise place et la plasticité des structures laminées telles que le cortex cérébral, l’hippocampe ou le cervelet. Notre objectif a été de caractériser le phénotype comportemental et neurochimique de la souris scrambler au cours du développement post-natal et à l’âge adulte. Les premiers signes de l’ataxie cérébelleuse sont observables dès 8 jours et sont majorés au cours des 2ème et 3ème semaines de vie post-natale. A l’âge adulte, la souris se caractérise par un trouble important de la coordination motrice et une hyperactivité locomotrice exacerbée et stéréotypée (comportement de rotation) lorsque l’animal est placé en milieu aquatique. Les tests du labyrinthe aquatique de Morris et de l’alternance spontanée mettent en évidence des déficiences possiblement causées par un trouble du guidage visuo-moteur et la désinhibition comportementale. Chez ces souris, l’activité métabolique régionale évaluée par le marquage de la cytochrome oxydase est relativement préservée dans le cervelet ; elle est en revanche altérée dans diverses régions du tronc cérébral qui lui sont associées ainsi que dans l’hippocampe et certaines régions corticales. Le comportement de rotation stéréotypé et l’hyperactivité causés possiblement par un déséquilibre neurochimique acétylcholine/dopamine a été évalué dans un rotamètre avec ou sans injection préalable d’un antagoniste des récepteurs D2. Parallèlement, l’innervation cholinergique du système nerveux central, révélée par l’activité de l’acétylcholinestérase était diminuée dans la substance noire pour laquelle nous avons observé une désorganisation et une perte partielle des neurones dopaminergiques. Bien que les atteintes multiples compliquent l’étude structuro- fonctionnelle de ce mutant, nos résultats ont permis de préciser le phénotype scrambler en le comparant aux autres mutants de la voie de la rééline. Ces mutants font l’objet aujourd’hui d’un intérêt croissant pour la modélisation non seulement de l’ataxie mais également de certaines maladies neurologiques et neuro-psychiatriques comme l’autisme et la schizophrénie / The Dab1scm scrambler mice is a cerebellar ataxic mutant spontaneously mutated for a gene encoding a protein of the reelin signaling pathway involved in the development and the plasticity of laminated structures such as the neocortex, the hippocampus, and the cerebellum. Our objective was to characterize the behavioral and neurochemical phenotype of the scrambler mice during postnatal developmental and adult stages. The first signs of cerebellar ataxia are observable as early as 8 days and increase during the 2nd and 3rd weeks of postnatal life. Adult mouse is characterized by a significant disturbance of motor coordination and a locomotor hyperactivity which increases ans becomes stereotyped (circling) when the animal was placed in water. Morris water maze and spontaneous alternation highlight deficiencies possibly caused by disorder of visuomotor control and disinhibitory processes. Brain regional metabolic activity measured by cytochrome oxidase is relatively preserved in the mutant cerebellum. However, it is impaired in various connected regions of the brainstem as well as in the hippocampus and some cortical regions. Circling behavior and hyperactivity, possibly caused by a neurochemical imbalance between acetylcholine and dopamine, were evaluated in a rotameter with or whithout prior injection of D2 receptor antagonist. In parallel, cholinergic innervation of the central nervous system measured by acetylcholinesterase activity is lower in the substantia nigra for which a partial disruption and loss of dopaminergic neurons is observed. Although the multiple alterations complicate the structuro-fonctional study of this mutant, results have clarified the scrambler phenotype by comparison with others mutants of the reelin pathway. This mutants are now subject to a growing interest in not only ataxia modeling but also some neurological and neuropsychiatric diseases
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Betydelsen av skogens slutenhet för gammelskogslaven långskägg, Usnea longissima / Importance of stand density for the old-growth forest lichen species Usnea longissimaLibell, Joel January 2019 (has links)
The epiphytic lichen Usnea longissima is strongly associated with old-growth forests and is declining. Previous studies have documented unimodal relationships between stand density and abundance of U. longissima. The aim of this thesis has been to investigate whether the same relationship is found in Sweden and to determine the optimum level of stand density. The study area (1.4 ha) was divided into a grid with 48 circular plots (10-m radius). Stand density was measured as basal area (m²/ha) using a relascope and abundance of U. longissima was measured as the length of the longest thallus present on the tree nearest the plot center. Usnea longissima was found in 42 plots (mean thallus length of 37 cm). The regression analyses between length of U. longissima and basal area showed that the relationship was not significant (R²=0.082, P=0.066), and tended to be linear rather than unimodal. However, plots with U. longissima had significantly lower basal area (30.4 m²/ha) than plots without the lichen (35.1 m²/ha). The basal area in U. longissima plots was higher than in Norwegian studies, but similar to other Swedish sites. Thus, my results correspond well with earlier studies that have documented higher basal area in U. longissima-locations in Västernorrland than in more oceanic areas in Norway. Thereby a basal area around 27-35 m²/ha seems most favorable for U. longissima in the study area. The lichen cannot develop large populations in dense stands, indicating that management operations to reduce the basal area might be needed in such stands.
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Estudo da transição dermoepidérmica dos enxertos de pele e sua relação com o surgimento de vesículas / A study of skin grafts dermal-epidermal junction and its relation to the onset of blistersAlmeida, Paulo Cezar Cavalcante de 04 June 2009 (has links)
O presente estudo foi realizado para esclarecer o surgimento de vesículas subepidérmicas em enxertos de pele comumente descritos como áreas enxertadas. Devido à discrepância existente entre a literatura, que afirma surgirem vesículas nessas áreas, e a nossa experiência clínica, onde não observamos tal fato, decidimos investigar o problema. Para isso, estudamos a transição dermoepidérmica (TDE), em 23 pacientes submetidos à enxertia de pele, para verificar se há ou não alteração dessa estrutura que pudesse justificar a formação de vesículas. Nos 23 pacientes estudados foram feitas duas biópsias: a primeira, imediatamente antes da excisão do enxerto, na área doadora - pele sã, considerada como amostra padrão normal da TDE - Amostra Padrão AD. Após 10 dias, realizou-se uma segunda biópsia, com o mesmo vazador, próxima à área da primeira biópsia - Amostra Teste - ENX. Cada amostra foi dividida em 2 partes iguais (46 amostras) e estudadas por microscopia de luz e por imunofluorescência direta (imunomapeamento), pesquisando-se a possível alteração da zona da membrana basal (ZMB) na TDE através dos antígenos penfigóide bolhoso, laminina, colágeno IV e colágeno VII. Na microscopia de luz estudou-se, em cada biópsia, a relação entre a medida linear do relevo da trasição dermoepidérmica e a medida linear do relevo da superfície da camada granulosa, logo abaixo da camada córnea, equivalente a medida linear da superfície da pele. Nas 46 amostras as análises por microscopia de luz e de imunomapeamento para os quatro antígenos evidenciou-se a manutenção do mesmo padrão morfológico. Não houve diferença no imunomapeamento. Observou-se relações lineares das medidas com médias de 1,17 para a amostra AD e 1,44 para a amostra ENX, diferença que foi estatisticamente significativa, porém conservando a manutenção do padrão da TDE em relação à pele normal. Foi observada a manutenção do padrão do relevo da TDE no enxerto, em relação à pele sã, doadora. / SUMMARY: The present study has been done to elucidate the onset of subepidermal blisters in skin grafts, usually mistaken as grafted sites. Due to the discrepancy between literature - assigning this onset of blisters in grafts and our experience opposite we have decided to carry out this study. To do so we have studied the dermal-epidermal junction in 23 burned patients who underwent skin grafting so that we could verify whether or not there could be any alteration in the dermal-epidermal junction structure that may explain this fact. Among the 23 studied patients, two biopsies were carried out: the first one just before harvesting the skin graft from donor site healthy skin. The so called sample was regarded as an ordinary standard one of the dermal-epidermal junction STANDARD SAMPLE - DS. After graft take, by ten days, a second biopsy was performed with the same punch, close to the first biopsy TEST SAMPLE GS. Both samples were split into two equal parts (46 samples) and studied using light microscopy and direct immunofluorescence (immune mapping), searching for possible alterations in basement membrane zone in the dermal-epidermal junction through bullous pemphigoid, laminin and types IV and VII collagen antigens. On light microscopy, relation between the linear measure of dermal-epidermal junction projection and that of stratum granulosum surface, just underneath the stratum corneum, corresponding to skin surface, was studied in each biopsy. The four analyses of the antigens by light microscopy and direct immunofluorescence in the 46 samples clearly showed the keeping of the same pattern, either for STANDARD SAMPLE DS or TEST SAMPLE GS. There were no differences on the immune mapping. Regarding the relation of the linear measures it was noted a mean of 1.17 for STANDARD SAMPLE DS and a mean of 1.44 for TEST SAMPLE GS. Such difference was statistically significant. Nevertheless, it maintained the keeping of the same pattern of dermal-epidermal junction when compared to healthy skin.
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