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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.
441

Estendendo o espectro das degenerações lobares frontotemporais: revisão de uma série clinicopatológica de 833 de demências / Extending the neuropathological spectrum of frontotemporal lobar degenerations: review of 833 prospectively assessed dementia cases

Grinberg, Lea Tenenholz 22 June 2006 (has links)
As demências Frontotemporais (DFT) compreendem 2 fenótipos clínicos: distúrbios comportamentais ou de linguagem. Coletivamente, as DFT podem ser causadas por um grupo diversas de doenças neurodegenerativas chamadas degeneração lobar frontotemporal (DLFT). Novas entidades têm sido descritas neste grupo e o conceito está em constante evolução. Parte dos mecanismos envolvidos na morte celular nas DLFTs também são observados n envelhecimento normal. Determinar as entidades e freqüência das DLFTs em uma série com utilização de imunoistoquímica. Uma série prospectiva de 833 casos avaliados prospectivamente no Centro de Pesquisas de Doença de Alzheimer da Washington University - EUA. Os casos de DFT foram selecionados por critérios clínicos e a classificação neuropatológica foi baseada em protocolos universalmente aceitos para DLFT. Dos casos de demência, 53(6,3%) atenderam aos critérios clínicos e neuropatológicos para DLFT. Outros 8 casos atenderam apenas aos critérios clínicos de DFT. As tauopatias representaram 40% dos casos. Entretanto, a maioria dos casos apresentava inclusões ubiquitina-positivas e tau-negativas. Esclerose hipocampal e alterações do tipo Doença de Alzheimer foram encontradas em 12 e 10 casos, respectivamente. Apesar da DLFT-U ter sido a entidade mais freqüente nesta série, entidades e menos comuns não incluídas nas recomendações de McKhann também podem apresentar fenótipo clínico de DFT. A inclusão destas novas entidades é mais uma evidência de que os sintomas clínicos são mais dependentes das áreas acometidas do que da entidade em si. A melhor compreensão desses mecanismos tem um grande potencial em auxiliar no desenvolvimento de medidas que possam modular ou retardar os efeitos do envelhecimento no cérebro, além é claro de trazer possibilidade de tratamento, hoje inexistente, para os pacientes acometidos. / Frontotemporal dementia (FTD) encompasses two clinical phenotypes: progressive behavioral change and language disorder. Collectively, FTD may be caused by a diverse group of neurodegenerative diseases called frontotemporal lobar degenerations (FTLDs). New entities have been described and the nosology of FTLDs continues to evolve. To determine the type and frequency of FTLDs in a series using contemporary immunohistochemical methods. Eight hundred and thirtythree dementia cases were prospectively assessed at Washington University Alzheimer Disease Research Center (WUADRC) and cases with clinical FTD were identified using existing diagnostic criteria and neuropathologic entities were ascertained using immunohistochemistry and contemporary diagnostic criteria. Of the dementia cases, 53(6.3%) met clinical criteria for FTD; 45(5.1%) fulfilled both clinical and neuropathological criteria for FTLD, and another 8 fulfilled only the clinical criteria. Forty percent of the cases were tauopathies. However, most FTLD cases were characterized by ubiquitin-positive, tau-negative inclusions. Co-existing hippocampal sclerosis and AD-type changes were observed in 12 and 10 cases, respectively. Although FTLD-MND-type is the most frequent FTLD in this prospectively assessed series, less common entities not included in the McKhann criteria, may also present clinically as FTD and should be considered as part of the neuropathologic spectrum of FTLDs that may be encountered in the dementia clinic. The better understanding of the cell death mechanisms related to those entities is likely to contribute for the development of a treatment for FTLD as well for a way of modulate brain aging.
442

Cefaléia crônica diária: classificação, estresse e impacto sobre a qualidade de vida

Galego, José Carlos Busto 28 June 2006 (has links)
Made available in DSpace on 2016-01-26T12:51:49Z (GMT). No. of bitstreams: 1 galego_tese.pdf: 557418 bytes, checksum: bec585bbf3ad75dc7e39d9820a6b0dbc (MD5) Previous issue date: 2006-06-28 / Chronic daily headache (CDH) is a heterogeneous group of headaches that occurs 15 or more days per month, lasting more than four hours, including those associated with medication overuse. The objectives of this study were: to classify Chronic Daily Headache; to assess the quality of life and level of stress of the patients with this type of headache. Casuistic and Method: A hundred patients, from both sexes, with minimum age of 18 years old were prospectively studied. The inclusion criterion was the presence of primary headache with more than 4-hour duration, a frequency of 15 days or more monthly, in the last three months. The diagnosis was according to the second edition of The International Classification of Headache Disorders (ICHD-II) criteria. The SF-36 questionnaire to observe quality of life and Lipp´s Inventory of Stress Symptoms to diagnose stress were used. Patients with chronic organic disease were not included. Results: The patients´ mean age was 38.8 years. The majority (87%) was women. CDH mean duration was 4.0 years. Applying the ICHD-II criteria, 17 different types of diagnosis were necessary to classify CDH. Between these types of diagnosis, 11 presented migraine (80% of the patients). The types with migraine had lower scores according to SF-36 either in physical function (p=0.0015) and social function (p=0.033). A total of 46% of the patients overused medication. Their scores were lower in physical function (p=0.008), bodily pain (p=0.037) and role emotional (p=0.046). Ninety patients presented stress, prevailing the psychological symptoms in 94.5%. Between the patients who presented stress, 2 were at the alert phase, 33 at resistance phase, 46 at almost exhaustion and 9 at exhaustion phase. Stress diminished significantly the scores at the SF-36, except on physical function. There was no association between stress and medication overuse. Comparing the stress phases with SF-36 scores, except on bodily pain scale, the resistance phase showed significant higher scores than the almost exhaustion phase. Conclusions: CDH is the result of a convergence of several types of headaches that integrates the second edition of The International Classification of Headache Disorders. Most patients presented stress and half of them were at the almost exhaustion phase. Stress produced significantly reduction in all scales from SF-36 questionnaire, except on physical function. The patients with stress at the almost exhaustion phase compared with those at the resistance phase showed significant lower scores in all scales of SF-36 questionnaire, except on bodily pain. / Cefaléia crônica diária (CCD) compreende um grupo heterogêneo de cefaléias que se manifestam em 15 ou mais dias por mês, durando mais de 4 horas, incluindo as cefaléias associadas com o uso excessivo de medicação. Os objetivos desse estudo foram: classificar a cefaléia crônica diária, avaliar a qualidade de vida e o nível de estresse dos pacientes com esse tipo de cefaléia. Casuística e Método: Foram estudados de forma prospectiva 100 pacientes de ambos os sexos e idade mínima de 18 anos. O critério de inclusão foi presença de cefaléia primária, durando mais de 4 horas, com freqüência de 15 ou mais dias por mês, nos últimos três meses. O diagnóstico foi em acordo com os critérios da segunda edição da Classificação Internacional de Cefaléias (CIC-II). Foram aplicados o Questionário SF-36 para verificar qualidade de vida, e o Inventário de Sintomas de Estresse de Lipp, para diagnosticar estresse. Não foram incluídos pacientes com doenças orgânicas crônicas. Resultados: A média de idade dos pacientes foi 38,8 anos. A maioria do grupo (87%) foi constituída de mulheres. A duração média da CCD foi 4,0 anos. Aplicando os critérios da CIC-II, foram necessários 17 diferentes tipos de diagnósticos para classificar a CCD. Dentro desses tipos de diagnósticos, em 11 havia migrânea (80% dos pacientes). Os tipos com migrânea obtiveram no SF-36 pontuações menores em capacidade funcional (p=0,0015) e aspectos sociais (p=0,033). Em 46% dos pacientes havia uso excessivo de medicação e esses obtiveram pontuações menores em capacidade funcional (p=0,008), dor corporal (p=0,037) e aspectos emocionais (p=0,046). Noventa pacientes apresentaram estresse, predominando os sintomas psicológicos em 94,5%. Entre os pacientes que apresentaram estresse, 2 estavam na fase de alerta, 33 em resistência, 46 em quase exaustão e 9 em exaustão. Estresse diminui significativamente as pontuações no SF-36, exceto para capacidade funcional. Não houve associação entre estresse e uso excessivo de medicação. Comparando as fases do estresse com pontuações no SF-36, com exceção da escala dor corporal, a fase resistência apresenta pontuações significantemente maiores, que quase exaustão. Conclusões: A CCD é o resultado da convergência de vários tipos de cefaléias que integram a segunda edição da Classificação Internacional das Cefaléias. A grande maioria dos pacientes apresentou estresse e a metade desses se encontravam na fase de quase exaustão. O estresse produziu redução significativa em todas as escalas do questionário SF-36, com exceção da capacidade funcional. Os pacientes com estresse na fase de quase exaustão, quando comparados aos da fase de resistência apresentaram pontuações significativamente menores em todas as escalas do questionário SF-36, menos em dor corporal.
443

Estudi de l’estat de seleni en sang i en líquid cefaloraquidi de pacients pediàtrics amb malalties neurològiques

Tondo i Colomer, Mireia 14 February 2012 (has links)
L’objectiu principal d’aquesta tesis doctoral ha estat estudiar l’estat del Se en sang i LCR de pacients amb errors congènits del metabolisme amb tractament dietètic i altres trastorns neuropediàtrics de diferent etiologia. En el primer treball ens plantejàvem l’establiment de valors de referència per a determinats elements traça en sang total. La necessitat venia de la inexistència d’estudis sobre l’estat d’aquests elements en poblacions pediàtriques afectades de diferents errors congènits del metabolisme. En el segon treball ens plantejàvem l’establiment de valors de referència per a seleni en LCR. La necessitat venia de la inexistència d’estudis sobre l’estat d’aquest element en poblacions pediàtriques i de la possible associació entre una alteració de l’estat de Seleni i algunes disfuncions neurològiques. Un cop establerts els valors de referència de Se en LCR, el tercer treball consistia en valorar l’estat de Se en pacients amb malalties neurològiques per intentar detectar alguna deficiència o excés de Se en els líquids d’aquests pacients. A part de valorar l’estat de Se, preteníem valorar també altres paràmetres bioquímiques com HVA, 5-MTHF, 5-HIAA, proteïnes, activitat de GPx i pterines, per tal de veure si les correlacions observades en l’anterior treball es mantenien. Finalment, l’últim treball es centrava en l’estudi d’un grup de pacients amb uns valors de Se en LCR permanentment elevats sense tenir-ne una explicació clara. Aquests pacients (que s’havien identificat en el tercer treball) estaven afectats de la síndrome de Kearns-Sayre (malaltia mitocondrial que es manifesta per deleció del DNA mitocondrial). En aquest nou treball ens plantejàvem l’estudi d’uns paràmetres bioquímics que ens permetessin detectar la disfunció del plexe coroïdal en pacients afectats d’aquesta síndrome. Així doncs i a títol de discussió, una de les nostres principals necessitats pel control regular dels pacients amb malalties metabòliques i tractament dietètic era la monitorització de diferents elements traça en diferents fluids biològics. Tradicionalment s’havia descrit deficiències d’alguns d’aquests elements en pacients que tenen com a base del seu tractament les dietes restrictives. De tots els elements, el Se semblava un candidat ideal, ja que prèviament s’havien descrit deficiències en algunes malalties, com la fenilcetonúria.La importància del Se radica en que és un element essencial per al correcte funcionament de les selenoproteïnes. Per tant, ens semblava d’interès monitoritzar les concentracions de Se tant en sang (com a marcador de dèficit nutricional) com en LCR (com a marcador potencial de mecanismes fisiopatològics en malalties d’àmbit neuropediàtric). Les fites més importants del nostre treball han estat tres: 1. L’estandardització del procediment en sang ha permès establir la tècnica de forma rutinària per al control de trastorns nutricionals al nostre centre. Des d’un punt de vista científic, la conclusió més important és que el dèficit de seleni és comú a les malalties metabòliques amb tractament dietètic i que per tant el seu estudi i suplementació són necessàries per a l’òptim control de les malalties. 2. Respecte a l’estudi del seleni a nivell central, les aportacions han estat més rellevants ja que era un camp poc estudiat. Hem establert per primera vegada valors normals de Se en LCR per a una població pediàtrica i confirmat que el cervell es un òrgan que regula mot bé l’homeòstasi d’aquest element traça, ja que els valors eren independents dels observats en sang. 3. Especialment rellevant creiem que és el perfil que ens va permetre valorar la funció del plexe coroïdal en la síndrome de KSS i el diagnòstic directe d’un cas. Aquest resultats no tan sols tenen un valor per a la pràctica diagnòstica, sinó que obren la porta a la investigació d’altres malalties en les que s’afecta el plexe coroïdal. / PhD STUDENT NAME Mireia Tondo Colomer TESIS TITLE Blood and cerebrospinal fluid selenium status in paediatric patients affected with neurological diseases. SUMMARY Our objective was to study blood and CSF Se status in patients with IEM with dietary treatment and other neurological disorders with different clinical aetiology. In this first study our objective was the establishment of reference values for some trace elements in whole blood. At that time, studies of several trace element status for a paediatric population with different inborn errors of metabolism were scarce. To achieve this aim, we used an Induced Couple Plasma Mass Spectrometer (ICP-MS), which allowed multiple analyses of different trace elements using a small sample volume. Leftover samples form patients who came to our hospital for minor surgery were used as reference population. In this second study our objective was the establishment of cerebrospinal fluid selenium reference values. At that time, no previous studies of Se central nervous system status for a paediatric population existed in the scientific literature. CSF Se concentrations had to be considered in order to find out any possible association between Se status and some neurological functions. Moreover, the implications of Se in the synthesis and function of more than 20 selenoproteins indicated that central nervous system Se status was important. After the establishment of CSF Se reference values for a paediatric population, the next step was to evaluate Se CSF concentrations in paediatric patients with different neurological disorders. Previous studies demonstrated the tight regulation of Se homeostasis in brain as well as the evidence of the role of Se in CNS disorder pathophysiology. In spite of growing evidence of the role of Se in CNS, no studies of Se CNS status in a large cohort of paediatric patients affected with different neurological disorders had been carried out. Finally, our last study derived from the one before which allowed us to identify a group of patients with clearly high CSF Se values. The main common feature was that all patients had a mitochondrial DNA deletion syndrome (Kearns Sayre Syndrome). This group of patients was not included in the previous work and was treated separately.
444

Biomarkers of cognitive decline and dementia

Miralbell Blanch, Júlia 13 July 2012 (has links)
Cognitive impairment in the elderly encompasses many forms, ranging from subtle impairments in otherwise cognitively healthy individuals through mild cognitive impairment and dementia. Brain structural and functional changes underlie the observed cognitive impairment. Complementary to the clinical observation, biomarkers have been proposed as in vivo indicators of the underlying pathophysiology and neurobiological changes in a sufficiently reliable manner that they could be used to detect, track, and predict the disease course over time. In this thesis we used a combination of epidemiological and clinic-based approaches to investigate the mechanisms underlying vascular cognitive impairment (VCI) and Alzheimer’s disease (AD) and to identify possible biomarkers that could help early diagnosis of such conditions. To do so, a set of circulating and cerebrospinal fluid (CSF) biomarkers were studied in healthy and cognitively impaired subjects. Then, these measures were related to grey matter (GM) volumes, white matter (WM) integrity and cognition. The first two studies are part of the population-based Barcelona-ASIA neuropsychology study. Study I aimed to compare the cognitive patterns of risk markers for cerebrovascular disease (CVD) with the cognitive profile in relation to novel and traditional vascular risk factors (VRF) in a community-dwelling sample. Biomarkers of inflammation, endothelial dysfunction and vascular thrombosis were selected. Results showed that VRF and circulating markers of inflammation and endothelial dysfunction predicted performance in several cognitive domains. Cognitive patterns of inflammatory markers overlapped those related to VRF. Markers of endothelial dysfunction predicted lower performance in verbal memory. Study II was designed to further explore the structural changes mediating the relationships between risk markers of CVD and cognition. For that purpose the same set of markers of risk for CVD were related to GM atrophy and WM integrity and cognition. The main finding was an association of inflammation and vascular thrombosis with WM integrity loss in cortico-subcortical pathways and association fibres of frontal and temporal lobes. As expected, none of the biomarkers was related to GM volume changes. Vascular thrombosis also predicted lower performance in processing speed. The third study is a memory clinic-based investigation that was conducted aiming to test the potential use of CSF biomarkers cut-offs as components for the diagnostic work-up in AD. We assessed GM and cognitive patterns in cognitively impaired subjects using CSF Aβ1-42, t-tau and p-tau181 cut-offs as grouping criteria. Results indicated that patients with abnormal CSF levels of t-tau and p-tau (but not Aβ1-42) showed impairment and signs of regional GM atrophy in brain regions characteristic for AD, compared to those with normal levels. More specifically, GM volume differences were found in temporal, inferior parietal, lateral occipital and widespread prefrontal regions. Studies I and II show that risk markers of inflammation and vascular thrombosis are related to a VCI profile for both cognitive patterns and structural brain changes. A microvascular damage of WM projections in fronto-subcortical pathways, but not GM atrophy, could mediate the association between these pathogenic processes and cognitive performance. Markers of endothelial dysfunction are related to a different cognitive pattern which is characteristic of both vascular and neurodegenerative mechanisms. Study III provides evidence that patients with abnormal CSF levels of t-tau and p-tau (but not Aβ1-42) show cognitive an AD profile according to GM density patterns and cognitive impairment. Taken together, these results suggest that, complementary to the clinical observation, plasma and CSF markers and structural imaging are well placed to improve early diagnosis of both VCI and AD. / El terme deteriorament cognitiu (DC) es refereix al contínuum de canvis cognitius associats a l’envelliment sa i patològic. El diagnòstic precoç de les persones amb DC és clau, ja que els tractaments són més eficaços quan s’inicien als inicis de la malaltia. Els biomarcadors s’han proposat com a eines pel diagnòstic precoç del DC i la demència. Es consideren indicadors in vivo de la patologia i s’han plantejat com a possibles eines pel diagnòstic, pronòstic i seguiment del DC i la patologia subjacent. L’objectiu general de la present tesi era explorar els mecanismes patofisiològics subjacents al deteriorament cognitiu vascular (DCV) i la (MA). Per aquest motiu, vàrem mesurar diversos biomarcadors sanguinis i de LCR en persones sanes i en persones amb diagnòstic de deteriorament cognitiu i vàrem relacionar-los amb canvis de l’estructura cerebral i de la cognició. L’objectiu final era identificar possibles biomarcadors pel diagnòstic precoç d’aquestes malalties. Els estudis I i II s’emmarquen dins del projecte Barcelona-ASIA Neuropsicologia i tenien com a objectiu estudiar la relació entre biomarcadors en plasma de malaltia vascular cerebral (MVC) i canvis estructurals i cognitius. Els resultats obtinguts mostren que els biomarcadors d’inflamació i trombosi vascular es relacionen amb un perfil de deteriorament cognitiu vascular tant a nivell cognitiu com estructural. La lesió microvascular dels tractes de SB còrtico-subcorticals mediaria l’associació entre aquests mecanismes i la cognició. Els marcadors de disfunció endotelial es relacionen amb un perfil cognitiu diferent, que és característic tant de processos vasculars com neurodegeneratius. L’estudi III té com a objectiu valorar el possible ús dels biomarcadors de líquid cefaloraquidi pel diagnòstic de la MA. En concret, vàrem estudiar els perfils estructurals i cognitius en persones amb deteriorament cognitiu emprant punts de tall de líquid cefaloraquidi com a criteri d’agrupació. Els resultats mostren que pacients amb DC i amb nivells patològics de t-tau i p-tau al LCR (però no d’Aβ1-42) presenten un perfil cognitiu i estructural de MA. En conclusió, els resultats obtinguts en la present tesi suggereixen que, complementaris a l’observació clínica, els biomarcadors de LCR i plasma, així com els indicadors de morfologia cerebral podrien ser d’ús pel diagnòstic precoç del DCL i la demència.
445

Personalidad y Adaptación Psicológica Parental en Discapacidad

Limiñana Gras, Rosa María 22 December 2006 (has links)
La presente tesis examina el proceso de adaptación psicológica en padres de niños con discapacidades congénitas. Para investigar el proceso de adaptación al estrés crónico de los padres se utilizó el Modelo de Personalidad de Millon (1990, 1994, 2004) y el modelo de afrontamiento al estrés de Folkman y Lazarus (1985). El estudio incluye 166 adultos, padres de niños con espina bífida severa o Mielomeningocele, Parálisis Cerebral y Fisura Labio-Velo-Palatina. Los resultados identifican estilos de personalidad, indicadores de la forma en que los padres responden y hacen frente a la discapacidad de un hijo, y sugieren un impacto diferencial en hombres y mujeres. Se discuten cuestiones derivadas de los condicionamientos género, así como la especial repercusión en la mujer. Finalmente, se sugiere un modelo de intervención interdisciplinar para una mejor adaptación de padres y madres a esta difícil experiencia vital. / This thesis analyzes the psychological adaptation of parents with children having congenital disabilities. Millon’s Personality Model (1990, 1994, 2004) and Lazarus and Folkman ‘s stress coping model , were used to investigate and analyze the process of adaptation of parents to chronic stress. The study included 166 adults, who were parents of children with severe spina bífida or Mielomeningocele, cerebral palsy, and cleft lip and cleft palate. The identified personality styles may serve as indicators of the way parents respond to and cope with a child's disability. The results also suggest that a child’s disability has a differential impact on men and women. Gender issues are evaluated, as well as any repercussions these may have on women. Finally, a model of interdisciplinary professional intervention for a better adaptation of fathers and mothers to this difficult life experience is suggested.
446

Lactate-releasing PLA scaffolds for brain regeneration

Álvarez Pinto, Zaida 25 July 2014 (has links)
Stroke and traumatic brain injuries are common causes of disability, with loss of nerve tissue due to secondary degeneration, gliosis, and often the formation of cavities that inhibit neural cell growth. Recent attempts at neural cell regeneration have therefore focused on the use of engineering materials that mimic the adult neural stem cell (NSC) niche, in order to establish an adequate environment for neurogenesis and differentiation. However, because the adult mammalian NSC niche has limited regenerative capacities, effective regeneration of the central nervous system (CNS) requires the reconstitution of its embryonic counterpart. Radial glia are bipolar cells with 1-2 µm-thick shafts that form a palisade and span the entire CNS parenchyma serving as substrates for neuronal migration. They contain high levels of glycogen and release L-lactate. Cerebral energy metabolism is a highly compartmentalized and complex process. The adult brain normally uses glucose as its primary energy source. However, before and immediately after birth, lactate is also an important energy source because at this time the level of glucose is low. Over the past decade, a role for lactate in fuelling the energetic requirements of neurons has emerged, not only during the perinatal period but also in adulthood. Initial evidence suggests that the metabolisms of NSC, neurons and astrocytes differ and that energy-dependent processes may influence the balance between NSC self-renewal and differentiation. The main goal of this thesis was to design an implantable biomaterial scaffold that reproduces the organization and supportive function of embryonic radial glia. Here we tested two types of poly L/DL lactic acid (PLA95/5 and PLA70/30), a biodegradable material permissive for neural cell adhesion and growth, as materials for nerve regeneration. PLA95/5 films were highly crystalline, stiff (GPa), and did not degrade significantly in the period analyzed in culture. In contrast, PLA70/30 films were more amorphous, softer (MPa) and degraded faster, releasing significant amounts of lactate into the medium. PLA70/30 performed better than PLA95/5 for primary cortical neural cell adhesion, proliferation and differentiation, maintaining the pools of neuronal and glial progenitor cells in vitro. Finally, for in vivo studies, we designed 3D cell-free biomimetic scaffolds consisting of electrospun PLA70/30 nanofibers. Radially aligned scaffolds released L-lactate and reproduced the 3D organization and supportive function of radial glia. These scaffolds implanted into cavities made in mouse brain fostered complete implant vascularization, sustained neurogenesis, and allowed the long-term survival and integration of the newly generated neurons. Our results suggest that PLA70/30 scaffolds mimic some of the physical and biochemical characteristics of the NSC niche. Overall, our results show that the endogenous CNS is capable of regeneration through the in vivo dedifferentiation induced by biophysical and metabolic cues, with no need for exogenous cells, growth factors, or genetic manipulation. / Las lesiones cerebrales son causas comunes de discapacidad que conllevan pérdida de tejido nervioso debido a la degeneración secundaria, la gliosis, y con frecuencia la formación de cavidades que inhiben el crecimiento neuronal. Recientemente, las terapias neuroregenerativas se han centrado en el uso de la ingeniería de materiales. Durante el desarrollo del SNC, las células de glia radial son las principales CMN que generan neuronas y glía y son retenidas en el cerebro adulto de especies que regeneran. Durante la neurogénesis temprana, los vasos sanguíneos invaden el SNC e interactúan con las CMN, dando lugar al nicho neurovascular. En el cerebro adulto, la glia radial puede ser recuperada al menos en cierta medida después de una lesión, lo que indica un intento endógeno en la reconstitución del nicho embrionario. Las células de glía radial son bipolares con 1-2 micras de espesor que forman una empalizada que abarca todo el parénquima del SNC sirviendo como sustrato para la migración neuronal. Esta glía radial contiene altos niveles de glucógeno liberando al exterior L-lactato. El metabolismo energético cerebral es un proceso altamente compartimentado y complejo. El cerebro adulto normalmente usa glucosa como fuente de energía primaria. Sin embargo, antes e inmediatamente después del nacimiento, el lactato es también una fuente de energía importante, debido a que los niveles de glucosa son bajos. En la última década, se ha visto que el lactato juega un papel importante como factor energético para las neuronas, no sólo durante el período perinatal sino también en la edad adulta. Nuevas evidencias sugieren que el metabolismo de las CMN, neuronas y astrocitos son diferentes y que los procesos dependientes de energía pueden influir en el equilibrio entre la auto-renovación y diferenciación de las CMN. El objetivo principal de esta tesis ha sido diseñar un andamio implantable que reprodujera la organización y función de soporte de la glía radial embrionaria. Para ello, hemos probado dos tipos de ácido poli L/DL láctico (PLA95/5 y PLA70/30), material biodegradable y permisivo para la adhesión y el crecimiento neuronal. Las películas de PLA95/5 eran cristalinas, rígidas (GPa), y no se degradaban significativamente en el período analizado durante el cultivo in vitro. Sin embargo, las películas de PLA70/30 eran más amorfas, menos rígidas (MPa) y se degradaban más rápido, liberando cantidades significativas de lactato en el medio. A diferencia del PLA95/5, en el 70/30 había una mejor adhesión neuronal, así como la proliferación y el mantenimiento de los progenitores neuronales y gliales in vitro. Finalmente, para los estudios in vivo, diseñamos andamios biomiméticos en 3D libres de células que consistían en nanofibras de PLA70/30. Los andamios radialmente alineados reproducían la organización 3D y la función de apoyo de la glía radial. Estos andamios implantados en la corteza cerebral del ratón ayudaron a la completa vascularización del implante, permitiendo la supervivencia y la integración a largo plazo de las neuronas recién generadas. Nuestros resultados sugieren que los andamios de PLA70/30 imitan algunas de las características físicas y bioquímicas del nicho neurovascular. En conclusión, nuestros resultados muestran que el SNC es capaz de regenerar de manera endógena a través de la des-diferenciación in vivo inducida por las señales biofísicas y metabólicas, sin necesidad de células exógenas, factores de crecimiento o manipulación genética
447

Diferents estats d’oligomerització entre els receptors 5-HT1A, GALR1 I GPR39 com a noves dianes terapèutiques en depressió

Tena Campos, Mercè 16 June 2015 (has links)
The type of serotonin receptor 1A (5-HT1A), the galanin type 1 (GalR1) and the orphan receptor 39 (GPR39) belong to the superfamily The serotonin receptor type 1A (5-HT1A), the galanin receptor type 1 (GalR1) and the orphan receptor 39 (GPR39) belong to the superfamily of G-protein-coupled receptors. All three GPCRs share, among other features, a relationship with the pathophysiology of unipolar depression associated with presence of zinc. The current paradigm with respect to these functional unities is that these receptors are not acting as monomeric forms but through complexs involving specific interactions with themselves or other receptors from the same family. This allows them to increase their functional possibilities exponentially, allowing versatility from a fixed number of receptors, and consequently also increases the number of pharmacological approachmes. The heterodimerization between 5-HT1A receptor and GalR1 has been previously described as an antagonistic interaction that could lead to unipolar depression. In this thesis we have shown that this interaction is avoided in the presence of zinc, giving a rational explanation for the antidepressant effect widely described for this cation. Although there was no published evidence regarding the interaction of these two receptors with GPR39, a receptor that is activated by zinc and whose expression depends on the concentration of this cation, in this thesis we have demonstrated the ability to interact of these three receptors in both forms GPR39-5-HT1A, 5-HT1A-GalR1 and the trimer GPR39-5-HT1A-GalR1. It has also been found that the functional capacity of the receptors is modified according the type of interaction in which these receptors are involved. So that monomeric and oligomeric forms have different signalling capacities. This would suggest that in the human brain all putative receptor configurations could be present, and that the presence of one or other would be regulated by zinc concentration. Deepening in the detailed molecular mechanism of the effect of zinc on these interactions should allow the development of new drugs for a disease with high prevalence in the nowadays society. / El receptor de serotonina del tipus 1A (5-HT1A), el de galanina de tipus 1 (GalR1) i el receptor orfe 39 (GPR39) pertanyen a la superfamília dels receptors acoblats a proteïna G. Tots tres receptors comparteixen, entre d'altres característiques, una relació amb la fisiopatologia de la depressió unipolar associada amb la presència de zinc. El paradigma actual, respecte a la unitat funcional d'aquests receptors, és que no actuen en forma monomèrica sinó mitjançant complexos que involucren interaccions específiques amb ells mateixos o amb altres receptors de la mateixa família. Això els hi permet augmentar les seves possibilitats funcionals exponencialment, permetent una gran versatilitat a partir d'un nombre fix de receptors, i en conseqüència també augmenta el nombre de possibilitats d'abordatge farmacològic. L'heterodimerització entre el receptor 5-HT1A i el GalR1 s'ha descrit prèviament com una interacció antagònica que podria donar lloc a la depressió unipolar. En aquesta tesi s'ha demostrat que aquesta interacció s'evita en presència de zinc, donant una explicació racional a l'efecte antidepressiu àmpliament descrit per a aquest catió. Tot i que no hi havia cap evidència publicada respecte a la interacció d'aquests dos receptors amb el GPR39, un receptor que és activat pel zinc i l'expressió del qual depèn de la concentració del mateix, en aquesta tesi s'ha demostrat la capacitat d'interacció d'aquests tres receptors, tant en les formes GPR39-5-HT1A i 5-HT1A-GalR1 com en el trímer GPR39-5-HT1A-GalR1. A més, s'ha trobat que la capacitat funcional dels receptors es veu modificada segons el tipus d'interacció en la que aquests receptors participen, de manera que les formes monomèriques i oligomèriques presenten una capacitat de senyalització diferent. Això faria pensar que en el cervell humà podrien trobar-se totes les configuracions potencials de receptors, i que la presència d'unes o altres estaria regulada per la concentració de zinc. L'aprofundiment en el mecanisme molecular detallat de l'efecte del zinc en aquestes interaccions hauria de permetre el desenvolupament de nous fàrmacs per a una malaltia d'alta prevalença en la població mundial.
448

La proteína quinasa C épsilon en la unión neuromuscular de mamífero adulto: Localización, regulación mediante actividad sináptica y acoplamiento a la liberación de acetilcolina

Obis Ibáñez, Teresa 07 November 2014 (has links)
La proteïna quinasa C (PKC) pertany a la família de les serina/treonina quinases y participa en diferents de senyalització regulant diverses funcions neurals. Les proteïnes d’unió a PKC intracel•lulars ,conegudes com receptors per a les quinases C activades (RACKs), són essencials per a la interacció de les isoformas de PKC activades amb els seus substrats endògens i contribueixen a la activitat catalítica de PKC. La isoforma novel epsilon (nPKCε) està altament expressada en el cervell i regula diverses funcions neurals. No obstant, la localització de la nPKCε a la unió neuromuscular (NMJ) i el seu paper en l’alliberament de la acetilcolina depenent d’activitat no ha estat descrites. Utilitzant una combinació de inmunohistoquímica i microscòpia confocal es va estudiar la distribució de la nPKCε en la NMJ de mamífer adult y es va observar la seva localització exclusiva en els terminals nerviosos motors. Aquesta tesis es centra en l’estudi de la participació de nPKCε en els processos sinàptics. Els estudis bioquímics mostren que la contracció muscular induïda per la activitat sinàptica promou canvis en els nivells de nPKCε en la membrana sinàptica a través del receptor tirosina quinasa B (TrkB). A més a més, la activitat de nPKCε resulta en la fosforilació de MARCKS, subtrat de PKC que participa en la neurotransmissió. S’ha estudiat, a més a més, el paper de nPKCε en la secreció de ACh, utilitzant el pèptid inhibidor de la translocació de nPKCε (εV1-2), que actua interrompent la interacció de nPKCε-RACK. Mitjançant tècniques de electrofisiologia de registre intracel•lular, s’ha investigat la implicació de nPKCε en el mecanisme de la secreció del neurotransmissor mitjançant la interacció amb PKC, PKA i els autoreceptors muscarínics M1/M2. La preincubació amb εV1-2 desacobla PKC del mecanisme de lliberació de ACh en diverses condicions de potenciació en la NMJ i altera el mecanisme muscarínic que modula la neurotransmissió a través de M1/M2. / La proteína quinasa C (PKC) pertenece a la familia de las serina/treonina quinasas y participa en diferentes vías de señalización regulando diversas funciones neurales. Las proteínas intracelulares de unión a PKC, conocidas como receptores para las quinasas C activadas (RACKs), son esenciales para la interacción de las isoformas de PKC activadas con sus sustratos proteicos endógenos y contribuyen a la actividad catalítica de PKC. La isoforma novel épsilon (nPKCε) está altamente expresada en el cerebro y regula diversas funciones neurales. No obstante, la localización de nPKCε en la unión neuromuscular (NMJ) y su papel en la liberación de acetilcolina (ACh) dependiente de actividad no han sido descritas. Utilizando una combinación de técnicas de inmunohistoquímica y microscopía confocal se estudió la distribución de nPKCε en la NMJ de mamífero adulto y se observó su localización exclusiva en los terminales nerviosos motores. Esta tesis se centra en el estudio de la participación de nPKCε en los procesos sinápticos. Los estudios bioquímicos muestran que la contracción muscular inducida por la actividad sináptica promueve cambios en los niveles de nPKCε en la membrana sináptica a través del receptor tirosina quinasa B (TrkB). Además, la actividad de nPKCε resulta en la fosforilación de MARCKS, sustrato de PKC que participa en la neurotransmisión. Se ha estudiado, además, el papel de nPKCε en la secreción de ACh, utilizando el péptido inhibidor de la translocación de nPKCε (εV1-2), que actúa interrumpiendo la interacción nPKCε-RACK. Mediante técnicas de electrofisiología de registro intracelular, se investigó la implicación de nPKCε en el mecanismo de secreción del neurotransmisor mediante la interacción con PKC, PKA y los autoreceptores muscarínicos M1/M2. La preincubación con εV1-2 desacopla PKC del mecanismo de liberación de ACh en diversas condiciones de potenciación en la NMJ y altera al mecanismo muscarínico que modula la neurotransmisión a través de M1/M2. / Protein kinase C (PKC) comprises a family of serine/threonine kinases, which regulates a variety of neural functions by playing central roles in several signaling pathways. Intracellular PKC-binding proteins, known as receptors for activated C kinase (RACKs), are essential for the interaction of activated PKC isoforms with its endogenous protein substrates and contributes to the catalytic activity of PKC. The novel epsilon isoform of PKC (nPKCε) is highly expressed in the brain and regulates several neural functions. However, the location of nPKCε at the neuromuscular junction (NMJ) and its role in the activity dependent acetylcholine (ACh) release are not described. Using a combination of immunohistochemistry and confocal microscopy, we studied nPKCε distribution in adult mammalian NMJ and we observed its exclusive localization at the motor nerve terminals. This dissertation focuses, moreover, on the study of nPKCε participation in synaptic processes. Biochemical studies have shown that muscle contraction induced by changes in synaptic activity promotes nPKCε levels in the synaptic membrane through receptor tyrosine kinase B (TrkB). Moreover, the activity of nPKCε results in MARCKS phosphorylation, a PKC substrate involved in neurotransmission. Furthermore, we have studied the role of nPKCε in neurotransmitter release, using the selective nPKCε translocation inhibitor peptide (εV1-2), which acts by disrupting the interaction nPKCε-RACK. By electrophysiological techniques (intracellular recordings), we investigated nPKCε involvement on the mechanism of neurotransmitter secretion by its interaction with PKC, PKA and muscarinic autoreceptors M1 / M2. Preincubation with εV1-2 uncouples PKC to ACh release in different enhancement conditions and alters muscarinic mechanism that modulates neurotransmission via M1 / M2 at the NMJ.
449

Human movement analysis by means of accelerometers : aplication to human gait and motor symptoms of Parkinson's Disease

Samà Monsonís, Albert 03 October 2013 (has links)
This thesis presents the original contributions of the author on the field of human movement analysis from signals captured by accelerometers. These sensors are capable of converting acceleration from some body parts into electric signals for further analysis. The progressive refinement and miniaturization of accelerometers has allowed the development of minimally invasive devices that can be used to ambulatory monitor human movements during daily live activities. The study's contributions mainly fall under two heads: first, the analysis of movement in Parkinson's disease (PD); and, second, the relationship between accelerometer signals and characteristics of gait. To this end, new methods for obtaining speed and length of strides and, also, for identifying people have been developed. In all these studies, a single sensor fixed to the patient's waist has been used. PD is a neurodegenerative disease characterized by movement alterations. The main motor symptoms of PD are 1) tremor, 2) bradykinesia or slowness of movements, 3) freezing of gait and 4) dyskinesia or abnormal involuntary movements. The first three symptoms primarily occur when the medication has not yet reached an effective therapeutic effect. These periods are commonly known as OFF periods or OFF motor state. On the other hand, periods when the patient is suitably responding to the medication are known as ON periods or ON motor state. Dyskinesias mainly appear when the medication blood level is excessive. Both dyskinesias and OFF motor states are caused by a defect in the medication administration. In this sense, a wearable device capable of detecting and recording dyskinesias and OFF periods represents an important tool that enables clinics to more accurately prescribe the medication regimen of a patient. The work done in the field of PD consisted in developing algorithms able to detect dyskinesias and both ON and OFF periods. These algorithms have been adapted to provide real-time detection, which enabled their employment in a pilot study. This clinical study has tested, for the first time, the automatic adjustment of medication performed by means of a subcutaneous infusion pump according to the dyskinesias appearance and motor state of PD patients. The experience gained in the treatment of accelerometric signals from PD has led to contribute in the field of gait analysis. First, new methods for obtaining speed and length of strides from a single sensor fixed to the patient's waist have been obtained. Not only the PD can benefit from this study, but other diseases such as diabetes or some orthopedotraumatological diseases can also benefit from its results. Finally, using some of the techniques of the previous studies, another important contribution has been made in the field of biometric person identification. The work presented shows how the signal obtained from a single accelerometer located at the waist not only enables the extraction of some gait characteristics but also permits the identification of a person through its gait pattern. The main theoretical contribution of this thesis has been the development of techniques based on the reconstruction of attractors. It has been shown that the usage of only a small number of features that characterize the reconstructed attractor obtained from a time series of acceleration measurements makes possible the extraction of important parameters of gait and the person identification. / La tesis que este documento recoge es una aportaci on al an alisis del movimiento humano a partir de las señales capturadas por aceler ometros. Estos sensores permiten convertir la aceleraci on producida por algunas partes del cuerpo en señales el ectricas susceptibles de un an alisis posterior. El progresivo perfeccionamiento y miniaturización de los aceler ometros ha permitido construir sensores poco invasivos y que pueden ser usados de forma ambulatoria para registrar los movimientos realizados en las actividades de la vida diaria del sujeto. La tesis se focaliza en dos ambitos. El primero, fundamentalmente cl inico, se ha centrado en el an alisis del movimiento en enfermos de la Enfermedad de Parkinson (EP). El segundo ambito, m as general, ha consistido en relacionar las señales acelerom etricas con caracter sticas de la marcha. Con este fin, se han desarrollado m etodos para la obtenci on de la velocidad de la marcha y la longitud del paso, as í como para la identificaci on de personas. En ambos ambitos se ha empleado un unico aceler ometro situado en un lado de la cintura. La EP es una enfermedad neurodegenerativa que produce primordialmente trastornos del movimiento en los pacientes que la sufren. Los principales sí ntomas motores de la enfermedad son 1) los temblores, 2) la lentitud de movimientos o bradicinesia, 3) la congelaci on de la marcha (freezing of gait FoG) y 4) los movimientos involuntarios o discinesias. Los tres primeros s ntomas aparecen cuando la medicaci on no ha alcanzado un efecto terape utico efectivo. Estos periodos se conocen habitualmente como per odo o estado motor OFF. Los periodos en los cuales la medicaci on hace efecto y los pacientes presentan una movilidad normal (o casi normal) son los periodos o estados motores ON. Las discinesias aparecen principalmente cuando el nivel de medicaci on en sangre es excesivo. Tanto las discinesias como los estados OFF son consecuencia de un defecto en la administraci on de la medicaci on. Un dispositivo no invasivo que detecte y registre las discinesias y ambos periodos ON y OFF supone una importante herramienta que permite al m edico prescribir con mayor precisi on la dosis de medicamento adecuada a su paciente. El trabajo realizado en esta tesis en el ambito de la EP ha consistido en el desarrollo de algoritmos de detecci on de discinesias y periodos OFF. Estos algoritmos han sido adaptados para proporcionar una detecci on en tiempo real, de forma que se han empleado ya en un estudio piloto en los que el ajuste de medicaci on suministrada por una bomba de infusi on subcut anea se realiza de forma autom atica en funci on de la presencia de discinesias y el estado motor del paciente. La experiencia ganada en el tratamiento de la señal acelerom etrica proveniente de enfermos de Parkinson ha permitido contribuir en el campo del an alisis de la marcha y realizar una aportaci on que relaciona varios par ametros de la misma con la señal que suministra un unico aceler ometro situado en la cintura. No solo la EP puede bene ciarse de este estudio, sino tambi en otras enfermedades como la Diabetes o algunas enfermedades ortop edicas y traumatol ogicas pueden aprovecharse de sus resultados. Por ultimo, usando algunas de las t ecnicas de los estudios anteriores, se ha realizado una importante contribuci on en el ambito de la identi caci on biom etrica de personas. Se ha puesto de mani esto que la señal proveniente de un unico aceler ometro situado en la cintura no solo permite obtener algunas de las caracter sticas de la marcha sino tambi en permite identi car a la persona a trav es del patr on de su marcha. La principal contribuci on te orica de esta tesis ha sido el desarrollo de t ecnicas basadas en la reconstrucci on de atractores. Se ha evidenciado que un n umero muy reducido de caracter sticas procedentes del atractor reconstruido a partir de una serie temporal de medidas de aceleraci on permite la extracci on de los par ametros de la marcha y la identi caci on de personas
450

A ASCENSÃO CELESTIAL DE PAULO DE TARSO: ANÁLISE DE 2 CORÍNTIOS 12,1-10 A PARTIR DA HISTÓRIA DA RELIGIÃO E DA NEUROTEOLOGIA / THE HEAVENLY ASCENT OF PAUL OF TARSUS: AN ANALYSIS OF 2 CORINTHIANS 12, 1-10 FROM HISTORY OF RELIGION AND NEUROTHEOLOGY

Nogueira, Sebastiana Maria Silva 11 September 2012 (has links)
Made available in DSpace on 2016-08-03T12:19:14Z (GMT). No. of bitstreams: 1 Sebastiana maria Silva.pdf: 1536000 bytes, checksum: 2487c2d3e1207d1baf47cde8279add8a (MD5) Previous issue date: 2012-09-11 / Fundação de Amparo a Pesquisa do Estado de São Paulo / The subject celestial journey , well familiar to the old mediterranean world, is based on the belief that the visionary can cross the boundary between humanity and divinity, a constant characteristic in apocalyptic literature. Old Jewish mysticism was seen as an important dimension of this tradition, that is the reason why the mystics used the term apocalypse to describe the revelation of their experiences. Paul s ascension to heaven, recounted in 2 Cor 12,1-10, is the only first hand account and the best evidence of ecstatic practice of celestial journey in first century Judaism. This text, one of great interest in the studies of New Testament, has been examined in thematic forms that extend from the recognition of the apostle as enjoyable to divinity - what granted him such a heroic achievement - to a punishment experience by the guardians of the celestial gates for finding in him no merit to approach the place of the presence of God. For long time, the studies that prevailed in the academy were those of the theological aspects of the passage, such as the spine in the flesh , the apostolic mission , Paul s opponents , among others. The language of the passage reveals important topics that were not considered together for a coherent interpretation of the text. The use of expressions from the Jewish mystical apocalyptic circle like "caught up", "Third Heaven", "hear unutterable words" and "a thorn for the flesh" by the apostle needs to be investigated for the comprehension of what Paul had in mind while using those terms. Another problem is the omission of the experimental approach described in the passage. The apostle reveals that he lived the experience recounted in 2 Cor 12,1-10. While he was telling the unknown status of his body during the rising, he highlights signs of the altered state of consciousness, an aspect that was not considered in the traditional analysis of the text. These problems are analyzed in this thesis take as instruments of the Religion History and the Neurotheology analysis. Models were built trying to demonstrate a correlation between brain activity and mystical experience. In this respect, we have to point out that the emergence of neurotheology, or spiritual neurology brings a progress to the area of religious experience. Some points of difficult interpretation in pauline text have been clarified under this perspective. The proposal of this study was to build a contextual frame to analyse the ecstatic experience of Paul. The study made it possible to infer that the interdisciplinary approach allows a more appropriate scenario to the understanding and interpretation of the text. / O tema viagem celestial , bem familiar ao mundo mediterrâneo antigo fundamenta-se na crença de que o visionário pode cruzar a fronteira entre a humanidade e a divindade, uma característica constante na literatura apocalíptica. O misticismo judaico antigo era visto como uma importante dimensão dessa tradição, razão pela qual os místicos usaram o termo apocalipse para descrever a revelação de suas experiências. A ascensão de Paulo ao céu, recontada em 2 Cor 12,1-10, é o único relato de primeira mão e a melhor evidência para a prática extática de viagem celestial no judaísmo do primeiro século. De grande interesse nos estudos do Novo Testamento o texto tem sido abordado em forma temática que se estende desde o reconhecimento do apóstolo como agradável à divindade o que lhe rendeu tal feito heróico a uma experiência de punição pelos guardiões dos portões celestiais por não ter sido encontrado nele mérito para aproximar-se do lugar da presença de Deus. Por muito tempo os estudos que predominavam na academia eram os de aspectos teológicos da passagem, tais como o espinho na carne , a missão apostólica , os oponentes de Paulo , entre outros. A linguagem da passagem revela pontos importantes não considerados de forma conjunta para uma interpretação coerente do texto. O uso por parte do apóstolo de expressões do círculo místico-apocalíptico judaico, tais como foi arrebatado , Terceiro Céu , ouviu palavras inefáveis e um espinho na carne precisa ser investigado para a compreensão do que Paulo tinha em mente ao utilizar tais terminologias. Outro problema é a omissão do enfoque experimental descrito na passagem. O apóstolo revela que vivenciou tal experiência recontada em 2 Cor 12,1-10. Ao relatar o desconhecimento do status do seu corpo durante a ascensão ele evidencia sinais do estado alterado de consciência, aspecto não considerado nas análises tradicionais do texto. Esses problemas que são abordados nesta tese tomam como instrumentos da análise a História da Religião e o da Neuroteologia. Modelos foram construídos tentando demonstrar uma correlação entre a atividade cerebral e a experiência mística. Há que se destacar, nesse sentido, que o surgimento da neuroteologia ou neurologia espiritual constitui-se em um avanço na área da experiência religiosa. Pontos de difícil interpretação no texto paulino foram elucidados dentro dessa perspectiva. A proposta deste trabalho, portanto, foi construir um quadro contextual em que a experiência extática de Paulo pudesse ser analisada. O estudo possibilitou inferir que a abordagem interdisciplinar permite alcançar um cenário mais apropriado para a compreensão e interpretação do referido texto.

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