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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Some Impacts of Septic Effluent On Hydromorphic Soils

Campbell, James Alfred 06 1900 (has links)
<p> Measurements of soil atmosphere, soil physical parameters, coliform levels and ionic levels were made at 15 soil sites along Ancaster and Grindstone Creeks in winter, 1972-73 and July, 1973. Multivariate analysis of the data indicated large fluxes of septic effluent resulted in soil fabric alterations, anaerobosis, and elevated coliform, nitrate, chloride and sodium levels. According to ecological and health criteria, these hydromorphic soils have very serious limitations as processors and absorbers of septic effluent. </p> / Thesis / Master of Science (MSc)
162

Reconstructing the evolutionary history of cancer from allele-specific somatic copy number profiles

Petkovic, Marina 17 August 2023 (has links)
Die Intra-Tumor-Heterogenität spiegelt eine kontinuierliche Entwicklung zwischen den Zellen eines einzelnen Tumors wider. Sie ist eine der Hauptursachen für Arzneimittelresistenz bei der Krebsbehandlung. Um dieses Problem anzugehen, ist es daher wichtig, die Tumorevolution innerhalb eines einzelnen Patienten zu verstehen und erfolgreich zu modellieren. Bisherige Arbeiten haben sich nicht erfolgreich mit der Evolution von Tumoren befasst, deren Treiber strukturelle Veränderungen im Genom sind, wie z. B. somatische Kopienzahlveränderungen (SCNAs). Diese Arbeit befasst sich mit der Herausforderung, die Tumorevolution als Folge solcher Veränderungen zu charakterisieren. Wir verwenden einen phylogenetischen Ansatz zur Analyse von multiregionalen Datensätzen in einer großen Pan-Krebs-Kohorte. Wir untersuchen häufige SCNAs in verschiedenen Stadien der Tumorentwicklung und führen eine neue Methode, MEDICC2, ein, die die Tumorevolution innerhalb eines einzelnen Patienten rekonstruiert. In dieser Arbeit haben wir häufige SCNAs charakterisiert, die früh in der Tumorentwicklung auftreten. Aufgrund der Struktur der Kohorte ist die Charakterisierung der subklonalen SCNAs nicht eindeutig. Unsere neue Methode, MEDICC2, akzeptiert höhere Kopienzahlzustände und berücksichtigt die Verdopplung des gesamten Genoms, ein häufiges Ereignis in Tumoren, was eine genauere Modellierung der Tumorevolution ermöglicht. / Intra-tumor heterogeneity reflects an ongoing evolution among cells of a single tumor. It is one of the leading causes of drug resistance in cancer treatments. Therefore, to address this issue, it is important to understand and successfully model tumor evolution within a single patient. Previous work has failed to successfully address the evolution of tumors whose drivers are structural changes in the genome, such as somatic copy number alterations (SCNAs). This work addresses the challenge of characterizing tumor evolution as a result of such changes. We use a phylogenetic approach to analyze multi-region datasets in a large pan-cancer cohort. We investigate frequent SCNAs at different stages of tumor development, and introduce a new method, MEDICC2, which reconstructs tumor evolution within a single patient. In this work, we characterized frequent SCNAs that occur early in tumor development. Due to the structure of the cohort, the characterization of subclonal SCNAs remains inconclusive. Our new method, MEDICC2, accepts higher copy number states and takes into account whole-genome doubling, a frequent event in tumors, which allows for a more precise modeling of tumor evolution.
163

Klinische und molekularzytogenetische Charakterisierung von Aesthesioneuroblastomen

You, Xuejun 24 September 2002 (has links)
Das vom endonasalen Neuroepithel der Rima olfactoria entstandenen Aesthesioneuroblastom gehört zu den seltenen malignen Tumoren der Rhinobasis. Eine generelle Therapieempfehlung für die Behandlung dieses Tumors gibt es nicht, da bis heute etablierte, durch umfassende onkologische Studien untermauerte diagnostische und therapeutische Standards fehlen und der klinische Verlauf oft unberechenbar ist. Die Aufgabe der vorliegenden Arbeit bestand in der Überprüfung des chirurgischen Konzeptes bei der Therapie von Aesthesioneuroblastomen und in der erstmaligen molekularzytogenetischen Charakterisierung von Aesthesioneuroblastomen. Dazu wurden 18 Patienten mit Aesthesioneuroblastomen, die im Zeitraum zwischen 1988 und 2001 in der HNO-Klinik (17 Patienten) sowie in der Neurochirurgischen Klinik des Klinikums Fulda operiert wurden, untersucht. Die daraus resultierenden 22 Aesthesioneuroblastome wurden alle mit Hilfe der Vergleichenden Genomischen Hybridisierung (CGH) analysiert. Nach derzeitigem Kenntnisstand besteht die optimale Therapie der Aesthesioneuroblastome in der chirurgischen Resektion des Tumors mit nachfolgender stereotaktischer Bestrahlung. Für die operative Sanierung der Aesthesioneuroblastome und auch anderer Malignome der vorderen Schädelbasis ist das nachfolgende neue Fuldaer Konzept empfehlenswert: 1) Endonasale Resektion, wenn keine intrakranielle bzw. orbitale Tumorinfiltration vorliegt; 2) Subfrontaler Zugang, bei Infiltration des Gehirns; 3) Midfacial degloving, bei weit lateraler Tumorausbreitung; 4) Laterale Rhinotomie nur bei der Notwendigkeit der simultanen Exenteratio orbitae (bei orbitaler Tumorinfiltration). Aesthesioneuroblastomen sind durch ein typisches genetisches Muster charakterisiert, das Deletionen im Bereich der chromosomalen Arme 1p, 2q, 3p/q, 4p/q, 5p/q, 6q, 8p/q, 9p, 10p/q, 11p, 12q, 13q, 18q und 21q sowie Amplifikationen der Chromosomen 1p, 7q, 9q, 11q, 14q, 16p/q, 17p/q, 19p/q, 20p/q und 22p/q umfasst. Die beim Aesthesioneuroblastom häufigen DNA-Verluste im Bereich der chromosomalen Banden 1p21-p31 scheinen mit der Prognose dieser Tumoren assoziiert zu sein. Die Tumoren aller in der vorliegenden Studie am Malignom verstorbenen Patienten zeigten eine Kombination aus 1p21-p31-Deletion, dem Vorliegen des klinischen Stadiums C oder D sowie gleichzeitig einer schlechten Differenzierung (Grad III oder IV). Vermittels der CGH ist es möglich, eine klonale Zuordnung von Metastasen bzw. auch Rezidiven zu ihren primären Aesthesioneuroblastomen vorzunehmen. Die vorliegende Arbeit zeigt nicht nur neue Ansätze in der chirurgischen Therapie von Aesthesioneuroblastomen sondern auch die erste umfassende molekularzytogenetische Analyse dieser Tumorentität, auf dem Weg, das biologische Verhalten dieser Malignome genauer charakterisieren zu können. / Esthesioneuroblastoma (ENB) is a very rare malignant neoplasm arising from the olfactory epithelium which is recognized for its propensity for local recurrence and distant dissemination. Therapeutic management approaches for this neoplasm lack uniformity. The present study describes therapeutic management in ENB: Complete surgical resection combined with adjuvant stereotactic radiation therapy. Thereby, a new surgical concept is recommended: 1) Endonasal approach in cases without tumor infiltration of the orbit and/or the brain; 2) Subfrontal approach in cases with extended tumor infiltration of the intradural space or of the brain; 3) Midfacial degloving in cases with far lateral tumor spread, particularly fossa pterygoidea or pterygopalatina; 3) Lateral rhinotomy in all cases where an exenteratio orbitae is needed. Secondarily, the study characterizes the specific chromosomal alterations of ENB analyzed using Comparative Genomic Hybridization (CGH). ENB show frequently deletions of chromosoms 1p, 2q, 3p/q, 4p/q, 5p/q, 6q, 8p/q, 9p, 10p/q, 11p, 12q, 13q, 18q and 21q as well as DNA gains of chromosoms 1p, 7q, 9q, 11q, 14q, 16p/q, 17p/q, 19p/q, 20p/q and 22p/q. Deletions of the chromosomal region 1p21-p31 could be associated with bad prognosis since the tumors of all patients who died were of stage C or D and grade III or IV, and showed 1p21-p31 deletions. The analysis of primary ENB and their corresponding metastases shows clonality by a high concordance of alterations between the tumor pairs. For the first time, this study presents the specific chromosomal alterations of ENB pathogenesis and progression.
164

NÃvel de conhecimento do cirurgiÃo-dentista no diagnÃstico diferencial da fluorose dentÃria / Level of knowledge of dental surgeons about dental fluorosis

Maria de FÃtima Azevedo Souza 24 August 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O incremento na incidÃncia da fluorose dentÃria ocorrido nos Ãltimos tempos, à motivo de preocupaÃÃo dos epidemiologistas em nÃvel nacional e internacional. A diferenciaÃÃo entre as alteraÃÃes do esmalte fluorÃtico e nÃo fluorÃtico leva a importantes decisÃes em epidemiologia e saÃde pÃblica bucal. O objetivo deste estudo à investigar a capacidade dos cirurgiÃes-dentistas do serviÃo pÃblico de saÃde no municÃpio de Fortaleza, em diagnosticar a fluorose dentÃria, frente Ãs diversas afecÃÃes do esmalte dentÃrio, seus graus de severidade e a conduta terapÃutica apropriada a cada caso. Utilizou-se para isso um questionÃrio com questÃes semi-estruturadas, o qual foi aplicado a 200 cirurgiÃes-dentistas, de um universo de 527 profissionais do serviÃo pÃblico de saÃde de Fortaleza. O questionÃrio foi aplicado no local de trabalho dos participantes, cujas respostas se basearam na apresentaÃÃo de 20 fotografias digitalizadas de dentes com alteraÃÃes prÃprias do esmalte. A presenÃa ou ausÃncia de fluorose dentÃria e seus graus de severidade foram determinados pelo Ãndice de Dean. NÃo foram detectadas diferenÃas significativas no nÃvel de acerto do grau de fluorose, quando os respondentes foram classificados segundo a instituiÃÃo de graduaÃÃo (p>0,05). No entanto, aqueles profissionais menos experientes apresentaram melhor desempenho (p<0,05), tanto no diagnÃstico de fluorose, quanto na conduta mas nÃo no grau de severidade da doenÃa. Os profissionais gerenciados pela Secretaria Municipal de SaÃde obtiveram desempenho superior aos gerenciados pelo Estado, em todas as percepÃÃes do teste. Quanto ao agrupamento da amostra por especialidades, nenhuma diferenÃa significativa (p>0,05) foi encontrada entre os Grupos. A mÃdia de acertos no diagnÃstico diferencial da fluorose dentÃria foi de 7,70  0,15. Valores inferiores a 30% de acertos foram obtidos no diagnÃstico do grau de severidade da fluorose, destacando-se as formas mais graves como de maior percentual de acerto. A maioria (90%) dos respondentes admitiram ter sentido dificuldades no diagnÃstico da fluorose, apesar de 75% ter recebido informaÃÃo acerca do assunto no curso de graduaÃÃo, porÃm consideraram escassa e deficiente (79,5%). A mÃdia de acertos da conduta clÃnica foi considerada muito baixa (2,71  0,76). Cerca de 70% dos inquiridos solicitaram curso de capacitaÃÃo acerca do diagnÃstico diferencial da fluorose dentÃria. A partir desses resultados, conclui-se que os cirurgiÃes-dentistas que atuam no serviÃo pÃblico de saÃde de Fortaleza apresentaram um baixo nÃvel de conhecimento e falta de preparo adequado para o diagnÃstico da fluorose dentÃria, a percepÃÃo dos seus graus de severidade e definiÃÃo da conduta clÃnica apropriada. Sugere-se que estudos mais abrangentes sejam conduzidos a fim de identificar as carÃncias do setor pÃblico de saÃde, em todos os nÃveis de atenÃÃo / Increasing levels of dental fluorosis are a major concern to public health authorities. The ability to discriminate fluorosis from other enamel modifications is an important factor to support decision makers in epidemiology and oral health. The main objective of this research is to investigate the ability of the odontologists working for the public health services in Fortaleza, to discriminate fluorosis from other enamel alterations, the severity of the disease and the correct clinical approach. Two hundred dentists out of 527 professionals of the public health services answered a semi-structured survey, based on the evaluation of 20 digitalized pictures showing enamel modifications. The presence or absence of fluorosis, as well as the severity of the disease were determined according to the Deanâs index. We were unable to detect an effect of the school of graduation (p>0.05) on the ability to diagnose fluorosis. However, the youngest, less experienced dentists performed better (p<0.05) for both fluorosis diagnosis and to determine to adequate clinical approach for each case. Also, odontologists working in the city health services were more likely to get higher scores compared to the ones working for the state services, with an average of correct answers for differential diagnosis of 7.70  0.15. Although a few subjects achieved less than 30% of correct answers, pictures displaying more severe cases of fluorosis were more likely to result in correctly answered questions. The vast majority (90%) of the subjects reported to have a poor ability do diagnose fluorosis, although 75% had received information about that disease during undergraduation. The odontologists also displayed a very poor performance (2,71  0,76) in defining the best clinical approach, and about 70% of them asked for specific training for correctly diagnose dental fluorosis. Based on the above results, we conclude that most dental surgeons working for the public health services in Fortaleza displayed a poor knowledge about dental fluorosis and lack an adequate training to diagnose and treat that disease. Similar researchs in other regions of Ceara should be performed in order to better identify the deficiencies of the public health services, at different levels
165

Déficits cognitifs et altération de l'activité de réseau au cours de l'épileptogenèse dans un modèle expérimental d'épilepsie du lobe temporal / Cognitive deficits and network alterations during epileptogenesis in an experimental model of temporal lobe epilepsy

Chauviere, Laëtitia 02 April 2010 (has links)
L’épilepsie du lobe temporal (ELT) est la forme d’épilepsie partielle la plus fréquente chez l’adulte. Elle se caractérise par une période de latence pendant laquelle l’ELT se met en place. Cette période est appelée épileptogenèse. L’épileptogenèse reste une période inaccessible chez l’Homme. Cependant, les modèles animaux présentent l’avantage de pouvoir l’étudier, dans le but de prévenir l’ELT. Ainsi, mon travail de thèse a consisté à mettre en évidence des marqueurs prédictifs de l’épileptogenèse, sur le plan cognitif et électrophysiologique in vivo, à partir du modèle pilocarpine. Les résultats ont montré que dès le stade précoce de l’épileptogenèse, des déficits de mémoire spatiale corrélaient avec une diminution de la puissance des oscillations thêta chez les animaux pilocarpine, sans modification jusqu’au stade chronique. Au même stade, une diminution de la puissance et de la fréquence des oscillations thêta lors du comportement d’exploration a été observée. L’activité interictale, activité paroxystique présente chez les patients entre leurs crises et caractéristique du stade épileptogène dans les modèles animaux, ne corrèle pas directement avec les déficits cognitifs mais diminue la puissance des oscillations thêta dans l’onde après la pointe au cours de l’épileptogenèse mais plus au stade chronique, ce qui suggère une importante modification du réseau avant le stade chronique. On a également décrit deux types d’activité interictale dont les propriétés (amplitude, nombre) et la dynamique au cours du temps sont modifiées juste avant la première crise spontanée, ce qui pourrait constituer, comme les déficits spatiaux et l’altération du rythme thêta, un marqueur prédictif de l’épileptogenèse. De plus, une augmentation du couplage entre l’hippocampe et le CE est observée au cours de l’épileptogenèse mais plus au stade chronique, alors qu’une modification du flux de l’information entre ces deux structures au stade épileptogène précoce persiste jusqu’au stade chronique, indépendamment de la présence ou non d’activité interictale. Ces résultats mettent en évidence la construction d’un réseau épileptogène, un changement majeur du réseau avant la première crise spontanée, et des marqueurs qui pourraient être prédictifs de l’épileptogenèse. L’ELT, les oscillations et les fonctions cognitives faisant intervenir des propriétés de réseau, tels les processus de synchronisation, l’enregistrement de 15 structures au sein du lobe temporal a montré, à partir du modèle pilocarpine, un réseau doté de caractéristiques plus « small-world » (SW) qui tendrait à se synchroniser plus localement, avec une perte des connexions longue distance. Ces résultats pourraient expliquer les altérations de réseau observées précédemment au cours de l’épileptogenèse. L’analyse SW et de cohérence, à l’échelle de ce réseau de structures, lors de différents états (comportementaux, processus cognitifs), mettent en évidence des changements de la dynamique lors de ces états, en conditions normales et pathologiques. Toutes ces modifications de réseau doivent être sûrement recrutées dans la mise en place d’un cerveau épileptique et des altérations cognitives associées. / Temporal lobe epilepsy (TLE) is the most common form of partial epilepsy in adults. TLE is characterized by a latent period during which TLE takes place. This period is called epileptogenesis. In TLE patients, epileptogenesis is unexplored. However, the use of animal models, like pilocarpine model, allows the study of epileptogenic processes, in order to try to prevent TLE. Thus, my PhD work tries to yield some predictive markers of epileptogenesis, in the pilocarpine model. We studied cognitive and electrophysiological in vivo alterations in this model. We showed that there are early and persistent spatial deficits that correlate with a decrease of the power of theta oscillations, i.e. during the early stage of epileptogenesis and the chronic stage. At the same time, there is also a decrease of power and frequency of theta rhythm during exploratory behaviors. Interictal-like activity (ILA) is a pathological activity present during epileptogenesis in experimental models. ILA does not correlate with cognitive deficits, but decreases theta power after the spike, i.e. in its wave, during epileptogenesis but not during the chronic stage anymore. This suggests an important network alteration before the chronic stage. Indeed, we described two types of ILA, whose properties (number, amplitude) and dynamics evolved during epileptogenesis with a major switch just before the first spontaneous seizure. All together, these results may constitute, with spatial deficits and theta rhythm alterations, predictive markers of epileptogenesis. Moreover, we showed an increase in the coupling, ILA-dependent, between the hippocampus and the entorhinal cortex, during epileptogenesis but not during the chronic stage, whereas a reversal of the information flow between these two structures occurs at the early stage of epileptogenesis and persists without any modification till the chronic stage. These results suggest the build-up of an epileptogenic network, a major switch of network properties just before the first spontaneous seizure, and some markers that could be predictive of epileptogenesis. TLE, oscillations and cognition involved processes at the network level, in particular synchronization processes. These processes could be possible via oscillations, which allow information transfer between structures of the network, in order to provide behavioral and cognitive processing. Recordings performed in 15 different structures of the temporal lobe showed, in pilocarpine animals, a network with more “small-world” (SW) features, with a higher local clustering and a loss of long-range connections. These results could explain cognitive and oscillatory alterations observed previously during epileptogenesis. SW and coherence analysis, at the network level, between signals during different brain-states (behaviors and cognitive processes) showed changes in dynamics occurring during these states, in normal and epileptogenic conditions. All these modifications in network activities may be involved in the construction of an epileptic brain and in associated cognitive deficits.
166

Estudio de los efectos de la reducción de la expresión de Dyrk1A, mediante interferencia de RNA, sobre el fenotipo motor del model transgénico TgDyrk1A. Implantación de kis receptores glutamatérgicos de tipo NMDA

Ortiz Abalia, Jon 15 May 2008 (has links)
DYRK1A es uno de los principales genes candidatos que podrían explicar algunos de los defectos neurológicos asociados al fenotipo Síndrome de Down (SD); desde el retraso mental, rasgo común a todos los individuos con SD hasta los déficits motores, también muy frecuentes entre la población con SD. Con el fin de validar la implicación de DYRK1A en el fenotipo SD se ha desarrollado una estrategia de terapia génica basada en la reducción de la expresión del gen mediante interferencia del RNA, en el modelo transgénico TgDyrk1A, y se han evaluado los efectos en el fenotipo motor de estos animales. Además se ha estudiado la implicación de los receptores glutamatérgicos de tipo NMDA en las alteraciones motoras descritas en el modelo. Los resultados obtenidos en este trabajo ponen de manifiesto la validez de la estrategia desarrollada y apuntan a una desregulación de los receptores de NMDA como uno de los mecanismos moleculares subyacentes de las disfunción motora presente en el modelo TgDyrk1A. / The are growing evidences to consider DYRK1A as a candidate gene for some of the neurological alterations present in DS phenotype such as mental retardation which is a common feature in the syndrome, or motor deficits which show a high prevalence among DS individuals. With the aim to validate the contribution of Dyrk1A to DS phenothype, we have developped a gene therapy strategy based on RNA interference to reduce gene expression in the transgenic model TgDyrk1A, and we have evaluated the effects in the motor phenotype of these animals. Moreover, we have studied the implication of the NMDA glutamate receptor in the motor alterations present in the model. The results obtained validate the strategy developped and suggest the deregulation of the NMDA receptor as one of the main causes underlying motor dysfunction in TgDyrk1A mice.
167

Caracterização de Estafilococos Coagulase-Negativa de origem hospitalar e comunitária quanto à diversidade clonal e a determinantes de resistência antimicrobiana

Pinheiro, Luiza. January 2018 (has links)
Orientador: Maria de Lourdes Ribeiro de Souza da Cunha / Resumo: A alta frequência de Estafilococos Coagulase-Negativa (CoNS) na pele de indivíduos saudáveis e em doenças associadas ao sangue, associados à seleção de cepas resistentes devido a uso indiscriminado de antimicrobianos, tornou mais estreitos os limites entre o ambiente hospitalar e o comunitário quanto à distribuição de cepas. Objetivou-se, com este estudo, caracterizar isolados de CoNS de origem hospitalar e comunitária da cidade de Botucatu-SP quanto ao perfil clonal, analisar os aspectos de resistência à oxacilina pela aferição de metodologia de detecção, e investigar os determinantes de heterorresistência à vancomicina nessas cepas. As espécies estudadas incluíram S. epidermidis, S. haemolyticus, S. warneri, S. hominis, S. lugdunensis, S. capitis, S. saprophyticus, S. pasteuri, S. simulans e S. xylosus. O teste de disco-difusão (TDD) com discos de oxacilina e cefoxitina, fitas de Etest impregnadas com oxacilina e pesquisa do gene mecA por PCR em tempo real foram realizadas. A triagem em ágar com 6 e 8 µg/ml de vancomicina, microdiluição em caldo para aferição da Concentração Inibirtória Mínima (MIC), microscopia eletrônica de transmissão para verificar espessamento da parede celular e alterações fenotípicas por testes bioquímicos foram realizadas. O perfil clonal foi determinado por PFGE (Pulsed-Field Gel Eletrophoresis) e para clones de S. epidermidis, o MLST (Multilocus Sequence Typing). S. epidermidis apresentou alta diversidade clonal, mas presença de clusters no ambien... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The high frequency of Coagulase-Negative Staphylococci (CoNS) on the skin of healthy individuals and in bloodstream infections, together with the selection of resistant strains, has narrowed the boundaries between the hospital and the community environment for the distribution of strains. This study aimed to characterize CoNS isolated from clinical and colonization specimens of patients and individuals from Botucatu-SP, to compare their clonal profile, to analyze the determination of oxacillin resistance by the evaluation of the methodology of detection, and to investigate the determinants of reduced susceptibility to vancomycin in those strains. CoNS species included S. epidermidis, S. haemolyticus, S. warneri, S. hominis, S. lugdunensis, S. capitis, S. saprophyticus, S. pasteuri, S. simulans and S. xylosus. The disc diffusion test (DDT) using oxacillin and cefoxitin discs was employed, Etest strips impregnated with oxacillin and mecA gene detection by real-time PCR were used. An agar screening with 6 and 8 µg/ml of vancomycin, the broth microdiluition method for the Minimal Inhibitory Concentration (MIC), the transmission eletronic microscopy for evaluation of cellwall thickening and phenotypic modifications by biochemical tests were performed. Clonal profile was determined by PFGE (Pulsed-Field Gel Eletrophoresis) and, for S. epidermidis clones, MLST (Multilocus Sequence Typing). S. epidermidis presented high clonal diversity, despite some clusters circulating within hospi... (Complete abstract click electronic access below) / Doutor
168

Estudo da influência da cafeína sobre o efeito antidepressivo da privação de sono em pacientes deprimidos

Schwartzhaupt, Alexandre Willi January 2008 (has links)
Introdução: A privação de sono (PdS) tem sido utilizada como um estratégia alternativa para o tratamento do Transtorno Depressivo Maior (TDM), contudo sua eficácia e efetividade carecem de estudos homogêneos e de bom delinemento para dar um grau de evidência científica para seu uso na prática diária. Assim sendo, desde a primeira publicação, em 1971, num relato de caso de um paciente com TDM grave tipo melancólico, por Plug e Tölle, o mesmo estava assintomático no dia seguinte à privação total de sono. Contudo, na noite seguinte de sono seus sintomas depressivos retornaram. Nestes quase 40 anos desde esta publicação houve dezenas de estudos em sua maioria relatos de caso, série de casos ou até estudos abertos só que misturando pacientes com TDM com Depressão Bipolar sem mesmo distinguir se tipo I ou II. A cafeína com seu efeito estimulador poderia ser uma alternativa para facilitar a privação de sono. No entanto, não há dados sobre o sua potencial influência no efeito antidepressivo da PdS. O objetivo deste estudo é avaliar o efeito da cafeína na PdS em pacientes deprimidos unipolares moderados a graves não psicóticos. Métodos: Ensaio Clínico randomizado, duplo cego, cruzado, comparando cafeína contra placebo em pacientes deprimidos moderados a graves submetidos à privação total de sono (PdS). Os pacientes foram avaliados por itens da escala de Lader, HAMD- 6 itens, CGI Severidade e Melhora Global. Resultados: Foram avaliados 20 pacientes. Os pacientes que usaram cafeína mantiveram o mesmo escore de energia pré e pós-privação de sono (item energético-letárgico da escala de Lader) enquanto os do grupo placebo diminuíram o escore de energia pós-privação de sono. (p = 0,0045). Não houve diferença entre o grupo cafeína e placebo nos demais itens da escala de Lader. Conclusão: O uso combinado de cafeína e PdS pode ser uma estratégia útil para manter os pacientes mais acordados sem o prejuízo do cansaço da PdS em pacientes ambulatoriais deprimidos. Contudo, mais estudos envolvendo pacientes que tenham 10 respondido à PdS são necessários para verificar se a cafeína também não interfere nos resultados deste grupo. / Introduction: Sleep deprivation (SD) has been used as an alternative approach to treat major depressive disorder (MDD), however the efficacy and the effectiveness needs studies with homogeneity and better delineament to strengthen the evidence based medicine to the use in the practical daily use. Besides, since the 1° puplication in 1971 of a case report, by Plug and Tölle, in that one patient with severe melancholic depressive disorder achieved remission in the next day after a total sleep deprivation. However his depressive sintomtology was back after the next night of sleep. Since this almost 40 years, a lot of papers were puplished, and the majority where case report, case reports and open trials with patients with MDD, bipolar depression without make difference between tipe I or II. Caffeine, due to its stimulating effect, could be an alternative to promote sleep deprivation. However, there are no data about its potential influence on the antidepressive effect of SD. The objective of this study is to assess the effect of caffeine on SD in non-psychotic patients with moderate to severe unipolar depression. Methods: Randomized, double-blind, crossover clinical trial comparing caffeine and placebo in moderate to severe depressed patients who underwent total sleep deprivation (SD). The patients were assessed with items of the Bond-Lader Scale, the 6-item Hamilton Depression Rating Scale (HAMD-6), and the Clinical Global Impression (CGI)-Severity/Improvement. Results: Twenty patients participated in this study. The patients who consumed caffeine presented the same score of energy before and after sleep deprivation (lethargicenergetic item of the Bond-Lader scale), while the patients in the placebo group had a reduced score of energy after sleep deprivation (p = 0.0045). There was no difference between the caffeine and placebo groups in the other items of the Bond-Lader scale. Conclusion: The combined use of caffeine and SD can be a useful strategy to keep the 12 patient awake without impairing the effect of SD on depressed outpatients. However, further studies involving patients who have responded to SD are needed in order to verify if caffeine also does not interfere with the results in this group.
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Un décalage de l'alimentation déclenche une asynchronie entre l'horloge circadienne centrale et les horloges périphériques et engendre un syndrome métabolique / Shifting eating creates a misalignment of peripheral and central circadian clocks, which leads to a metabolic syndrome

Kobiita, Ahmad 12 February 2016 (has links)
La séquence des événements moléculaires engendrés par des perturbations de signaux externes qui peuvent affecter les horloges circadiennes, et générer des pathologies restait peu connue. Durant ma thèse, j’ai démontré au niveau moléculaire, comment déplacer l’horaire de l'alimentation chez la souris de la phase active à la phase de repos, altère le métabolisme à la suite d’une hypoinsulinémie durant la phase active, ce qui provoque une activation de PPARα qui reprogramme le métabolisme et l'expression de RevErbα et qui de ce fait décale l’horloge de 12h dans les tissus périphériques. Notamment, l’absence de PPARα dans le noyau suprachiasmatique empêche le décalage de l’horloge centrale. Ainsi, les phases d’activité et de repos contrôlées par l’horloge centrale ne sont plus alignées avec l'expression des gènes contrôlée par les horloges périphériques. Ce non-alignement crée un syndrome métabolique similaire à celui observé chez des individus soumis à des horaires de travail décalés. / The sequence of molecular events through which alterations in externals cues may impinge on circadian clocks, and generate pathologies, was mostly unknown. During my thesis work, I have molecularly deciphered, how switching feeding in mice, from the “active” to the "rest" phase [Restricted Feeding (RF)] , alters the metabolism through hypoinsulinemia during the “active” phase, leading to increased PPARα activity, thereby reprograming both metabolism and RevErbα expression and leads to a 12h circadian clock-shift in peripheral tissues.Most notably, the lack of PPARα expression in the suprachiasmatic nuclei (SCN) prevents a shift of the central clock. Therefore, the “active” and “rest” phases controlled by the SCN clock and gene expression controlled by the peripheral circadian clocks are misaligned. Most interestingly, this misalignment generates a metabolic syndrome-like pathology, similar to that associated with shiftwork schedules.
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Avaliação dos mecanismos de ação interceptiva e/ou embriotóxica do extrato aquoso de Plectranthus barbatus Andr.(bolbo-brasileiro) administrado a ratas prenhez no período de pré-implantação

Alvarenga, Cláudia Maria Domingues [UNESP] 24 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-24Bitstream added on 2014-06-13T18:45:06Z : No. of bitstreams: 1 alvarenga_cmd_dr_botfm_prot.pdf: 1786103 bytes, checksum: 14d9f0d294fb6c639b79eab0f8e823c6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente estudo foi verificar, experimentalmente, o possível mecanismo pelo qual o extrato aquoso de Plectranthus barbatus (boldo-brasileiro), planta utilizada popularmente como abortiva, atua sobre o organismo materno ou sobre o desenvolvimento do concepto durante o período de pré-implantação, correlacionando sua ingestão com possíveis alterações no transporte e desenvolvimento embrionário ou com alterações hormonais maternas... / The present study was conducted to determine the possible mechanism by which the aqueous extract of Plectranthus barbatus (brazilian-boldo), a plant used popularly as abortive agent, can lead to early loss of pregnancy, correlating this possible effect with morphological alterations in the embryo, oviductal motility dysfunctions or maternal hormonal level modifications...(Complete abstract, access undermentioned electronic address)

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