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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.
71

A Comparative Study of Habitat Complexity, Neuroanatomy, and Cognitive Behavior in Anolis Lizards

Powell, Brian James January 2012 (has links)
<p>Changing environmental conditions may present substantial challenges to organisms experiencing them. In animals, the fastest way to respond to these changes is often by altering behavior. This ability, called behavioral flexibility, varies among species and can be studied on several levels. First, the extent of behavioral flexibility exhibited by a species can be determined by observation of that species' behavior, either in nature or in experimental settings. Second, because the central nervous system is the substrate determining behavior, neuroanatomy can be studied as the proximate cause of behavioral flexibility. Finally, the ultimate causation can be examined by studying ecological factors that favor the evolution of behavioral flexibility. In this dissertation, I investigate behavioral flexibility across all three levels by examining the relationship between habitat structure, the size of different structures within the brain and total brain size, and behavioral flexibility in six closely-related species of Puerto Rican <italic>Anolis</italic> lizards. <italic>Anolis</italic> lizards provide an excellent taxon for this study as certain species, including those used here, are classified as belonging to different ecomorphs and are morphologically and behaviorally specialized to distinct structural habitat types.</p><p>In order to determine the presence of behavioral flexibility in <italic>Anolis</italic>, I first presented <italic>Anolis evermanni</italic> with a series of tasks requiring motor learning and a single instance of reversal learning. <italic>Anolis evermanni</italic> demonstrated high levels of behavioral flexibility in both tasks.</p><p>To address the pattern of brain evolution in the <italic>Anolis</italic> brain, I used a histological approach to measure the volume of the whole brain, telencephalon, dorsal cortex, dorsomedial cortex, medial cortex, dorsal ventricular ridge, cerebellum, and medulla in six closely-related species of Puerto Rican <italic>Anolis</italic> lizards belonging to three ecomorphs. These data were analyzed to determine the relative contribution of concerted and mosaic brain evolution to <italic>Anolis</italic> brain evolution. The cerebellum showed a trend toward mosaic evolution while the remaining brain structures matched the predictions of concerted brain evolution. </p><p>I then examined the relationship between the complexity of structural habitat occupied by each species and brain size in order to determine if complex habitats are associated with relatively large brains. I measured brain volume using histological methods and directly measured habitat complexity in all six species. Using Principal Component Analysis, I condensed the measures of habitat structure to a single variable and corrected it for the scale of each lizard species' movement, calling the resulting measurement relevant habitat complexity. I tested the relationship between relative volume of the telencephalon, dorsal cortex, dorsomedial cortex, and whole brain against both relative habitat complexity and ecomorph classification. There was no relationship between the relative volume of any brain structure examined and either relevant habitat complexity or ecomorph. However, relevant habitat complexities for each species did not completely match their ecomorph classifications. </p><p>Finally, I tested the levels of behavioral flexibility of three species of <italic>Anolis</italic>, <italic>A. evermanni</italic>, <italic>A. pulchellus</italic>, and <italic>A. cristatellus</italic>, belonging to three distinct ecomorphs, by presenting them with tasks requiring motor and reversal learning. <italic>Anolis evermanni</italic> performed well in both tasks, while <italic>A. pulchellus</italic> required more trials to learn the motor task. Only a single <italic>Anolis cristatellus</italic> was able to perform either task. <italic>Anolis evermanni</italic> displayed lower levels of neophobia than the other species, which may be related to its superior performance.</p><p>In combination, this research suggests that <italic>Anolis</italic> of different ecomorphs display different levels of behavioral flexibility. At the proximate level, this difference in behavioral flexibility cannot be explained by changes in the relative size of the total brain or brain structures associated with cognitive abilities in other taxa. At the ultimate level, the size of the brain and several constituent structures cannot be predicted by habitat complexity. However, behavioral flexibility in certain tasks may be favored by utilization of complex habitats. Flexibility in different tasks is not correlated, rendering broad comparisons to a habitat complexity problematic.</p> / Dissertation
72

A diffusion tensor imaging study of age-related changes in the white matter structural integrity in a common chimpanzee

Errangi, Bhargav Kumar 15 April 2009 (has links)
Diffusion Tensor Magnetic Resonance Imaging was used to examine the age-related changes in white matter structural integrity in the common chimpanzee. Fractional Anisotropy(FA), a measure derived from the diffusion tensor data is sensitive to developmental and pathological changes in axonal density, myelination, size and coherence of organization of fibers within a voxel and thus reflects the white matter structural integrity. There is substantial evidence that white matter structural integrity decreases with age in humans. The long-term goal of this study is to compare the age-related changes in the white matter structural integrity among humans and chimpanzess to provide potential insights into the unique features of human aging. Different methods, including Region Of Interest (ROI) analysis, Tract Based Spatial Statistics (TBSS) are used to describe age-related changes in FA in a group of 21 chimpanzees. Strengths and limitations of these methods were discussed.
73

An investigation into the neuroprotective and neurotoxic properties of levodopa, dopamine and selegiline /

Scheepers, Mark Wesley. January 2007 (has links)
Thesis (M.Sc. (Pharmacy)) - Rhodes University, 2008.
74

Macroscópia do encéfalo de catetos (Pecari tajacu, Linnaeus, 1758) / Macroscopy of the encephalon of collared peccaries (Pecari tajacu, Linnaeus, 1758)

Saraiva, Júlio César dos Reis 31 July 2017 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-11-27T14:28:09Z No. of bitstreams: 1 JulioCRS_TESE.pdf: 3302198 bytes, checksum: 7ca6307c0127e1a56312a219843109bd (MD5) / Rejected by Socorro Pontes (socorrop@ufersa.edu.br), reason: ref on 2017-12-22T13:50:23Z (GMT) / Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-12-22T13:51:05Z No. of bitstreams: 1 JulioCRS_TESE.pdf: 3302198 bytes, checksum: 7ca6307c0127e1a56312a219843109bd (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-02-20T14:30:36Z (GMT) No. of bitstreams: 1 JulioCRS_TESE.pdf: 3302198 bytes, checksum: 7ca6307c0127e1a56312a219843109bd (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-02-20T14:30:46Z (GMT) No. of bitstreams: 1 JulioCRS_TESE.pdf: 3302198 bytes, checksum: 7ca6307c0127e1a56312a219843109bd (MD5) / Made available in DSpace on 2018-02-20T14:31:00Z (GMT). No. of bitstreams: 1 JulioCRS_TESE.pdf: 3302198 bytes, checksum: 7ca6307c0127e1a56312a219843109bd (MD5) Previous issue date: 2017-07-31 / The collared peccary (Pecari tajacu), a small-sized, omnivorous and diurnal animal, lives in groups of up to 20 animals in several areas of Brazil, the Brazilian northeast included. It is easily adapted to captive breeding and stands out in relation to cattle as an alternative protein source for human consumption, in addition to other commercial applications, posing less damage to the environment. Because there is a scarcity of studies addressing this animal, this work aimed to perform craniometry and morphometry of its cranium, as well as to describe the morphology of the encephalon and its arterial vascularization, in ventral view. We used 14 animals that died of natural causes. These had both their carotid arteries cannulated and fixation in 10% formaldehyde was then performed. From that total, ten animals were injected with latex solution, duly stained, in order to make the blood vessels evident. The skin, as well as the musculature, were rebounded. Craniometric measurements were performed. Subsequently, the encephalons were removed from the crania for measurement, dissection and description. Photographs were taken for demonstration of the structures and, after collection, the database was assembled. In the statistical analysis of the metric data, unpaired Student's t-test and Pearson’s correlation study were conducted. Thus, a significant difference was observed between the male and female collared peccaries, with regard to the Total Head Length, as well as to the face length, the cranium width, face width, and right cerebral hemisphere length, always with higher values for males. In females, the left cerebral hemisphere is wider than the right one. There was a positive correlation between the variable total head length and the right cerebral hemisphere width, in both males and females. The brain-to-body weight ratio of the collared peccaries was, on average, 0.42%. This is a gyrencephalic animal with a developed neocortex, although without evidence of sulci and gyri symmetry between the right and left cerebral hemispheres, nor between the different specimens. The arterial vascularization of the base of the encephalon is presented as a closed circuit, which is dependent on the carotid artery of the encephalon, both the antimeres, and the basilar artery, in all the analyzed specimens. The middle cerebral arteries ranged from one to three vessels, originating from the rostral branch of the cerebral carotid artery. The basilar artery results from the confluence of the vertebral arteries of both the antimeres and the ventral spinal artery. This species tends to fit into type II, of De Vriese's classification / O cateto (Pecari tajacu), animal de pequeno porte, onívoro e de hábitos diurnos, vive em grupos de até 20 animais em diversas áreas do Brasil, inclusive no nordeste brasileiro. É de fácil adaptação à criação em cativeiro e se destaca em relação ao gado como fonte alternativa de proteína na alimentação humana, além de outras aplicações comerciais, com menor dano ao meio ambiente, pois necessita de uma menor área para sua criação. Por tratar-se de um animal ainda pouco estudado, este trabalho objetivou realizar a craniometria e a morfometria de seu encéfalo, bem como descrever a morfologia encefálica e sua vascularização arterial, em vista ventral. Foram utilizados 14 animais que vieram a óbito por causas naturais. Estes tiveram ambas suas artérias carótidas canuladas e, em seguida, realizou-se a fixação em formaldeído a 10%. Deste total, dez animais foram injetados com solução de látex, devidamente corado, para evidenciação dos vasos sanguíneos. A pele foi rebatida, bem como a musculatura. Foram realizadas as medidas craniométricas. Posteriormente, os encéfalos foram retirados dos crânios para a sua medição, dissecação e descrição. Fotografias foram realizadas para demonstração das estruturas, bem como, após a coleta, montou-se o banco de dados. Na análise estatística dos dados métricos, foi realizado o Teste t de Student não-pareado e o estudo de correlação de Pearson. Dessa forma, observou-se que existe diferença significativa entre o comprimento total da cabeça dos catetos macho e fêmea, bem como no comprimento da face, largura do crânio, largura da face e comprimento do hemisfério cerebral direito, sempre com maiores valores para o macho. Nas fêmeas, o hemisfério cerebral esquerdo apresenta-se mais largo que o direito. Ficou evidenciada uma correlação positiva entre a variável comprimento total da cabeça e a largura do hemisfério cerebral direito, tanto nos machos como nas fêmeas. A relação peso do encéfalo/peso do corpo dos catetos foi, em média, de 0,42%. É um animal girencéfalo, com neocórtex desenvolvido, embora sem evidência de simetria dos sulcos e giros entre os hemisférios cerebrais direito e esquerdo, ou entre os diferentes espécimes. A vascularização arterial da base do encéfalo apresenta-se na forma de circuito fechado, sendo dependente da artéria carótida do encéfalo, de ambos os antímeros, e da artéria basilar, em todos os espécimes analisados. As artérias cerebrais médias variaram de um a três vasos, tendo origem a partir do ramo rostral da carótida do encéfalo. A artéria basilar resulta da confluência das artérias vertebrais de ambos os antímeros com a artéria espinal ventral. Esta espécie tende a enquadrar-se no tipo II, da classificação de De Vriese / 2017-11-27
75

Os sulcos e giros na face súpero-lateral do lobo occipital / The occipital lobe convexity sulci and gyri

Raphael Vicente Alves 28 April 2014 (has links)
INTRODUÇÃO: A anatomia da face súpero-lateral do lobo occipital é tão complexa e variável que a sua descrição precisa não é encontrada nos livros clássicos de anatomia. Os sulcos e giros occipitais da convexidade cerebral encontram-se descritos com nomenclaturas diferentes de acordo com os diversos autores. O objetivo deste estudo foi investigar e descrever a anatomia da face súpero-lateral lobo occipital e esclarecer a sua nomenclatura. MÉTODOS: As configurações anatômicas dos sulcos e giros na face súpero-lateral do lobo occipital de 20 hemisférios cerebrais foram examinados a fim de identificar os padrões mais característicos e consistentes. RESULTADOS: Os sulcos occipitais mais característicos e consistentes identificados neste estudo foram o sulco intraoccipital, o sulco occipital transverso e o sulco occipital lateral. A morfologia da junção do sulco occipital transverso com o sulco intraoccipital foi identificada como sendo o aspecto mais importante para definir o padrão de giros cerebrais da face súperolateral do lobo occipital. CONCLUSÕES: O conhecimento das principais características dos sulcos e giros occipitais permite o reconhecimento de uma configuração básica do lobo occipital e a identificação de suas principais variações anatômicas / BACKGROUND: The anatomy of the occipital lobe convexity is so intricate and variable that its precise description is not found in the classic anatomy textbooks, and the occipital sulci and gyri are described with different nomenclatures according to different authors. The aim of this study was to investigate and describe the anatomy of the occipital lobe convexity and clarify its nomenclature. METHODS: The configurations of sulci and gyri on the lateral surface of the occipital lobe of 20 cerebral hemispheres were examined in order to identify the most characteristic and consistent patterns. RESULTS: The most characteristic and consistent occipital sulci identified in this study were the intraoccipital, transverse occipital, and lateral occipital sulci. The morphology of the transverse occipital sulcus and the intraoccipital sulcus connection was identified as the most important aspect to define the gyral pattern of the occipital lobe convexity. CONCLUSIONS: Knowledge of the main features of the occipital sulci and gyri permits the recognition of a basic configuration of the occipital lobe and the identification of its sulcal and gyral variations
76

Prevalência de desordens crânio cervicais em pacientes portadores de desordens temporomandibulares / Prevalence of cranio spine disorders in patients with temporomandibular disorders

Micelli, Ana Lígia Piza 02 August 2011 (has links)
Orientador: Wilkens Aurelio Buarque e Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-17T12:30:16Z (GMT). No. of bitstreams: 1 Micelli_AnaLigiaPiza_M.pdf: 2184195 bytes, checksum: a4d033795e359c7d94617f3a5557f149 (MD5) Previous issue date: 2011 / Resumo: O presente estudo teve como objetivos determinar a prevalência de Desordens Crânio Cervicais em voluntários portadores de Desordens Temporomandibulares; correlacionar os sinais e sintomas envolvidos no acometimento das duas patologias, discutindo possíveis associações; avaliar a possibilidade de contribuição para a elaboração de uma base de dados para diagnóstico, mais ampla. Foram selecionados 200 voluntários do serviço de triagem da Faculdade de Odontologia de Piracicaba da Universidade Estadual de Campinas, os quais foram avaliados por meio da ficha clínica elaborada pelo Centro de Estudos e Tratamento das Alterações Funcionais do Sistema Estomatognático (CETASE) para o diagnóstico de DTM. Os voluntários que apresentavam sinais e sintomas positivos para as Desordens Temporomandibulares foram submetidos a um novo exame clínico para avaliação de Desordens Crânio Cervicais. Os resultados obtidos demonstraram uma prevalência de 69% de Desordens Crânio Cervicais em voluntários portadores de Desordens Temporomandibulares. Entre os principais sinais e sintomas correlacionados de DTM e DCC observamos resultados estatisticamente significantes para dor nas articulações temporomandibulares (p=0,0168), dor espontânea para o músculo temporal (p=0,0049) e, dor à palpação para os músculos temporal (p=0,0016), masseter (p=0,0052) e trapézio (p=0121). Os exames físicos realizados para o diagnóstico de DCC foram bastante específicos, de modo a caracterizar corretamente 95,45% da amostra estudada. Como conclusões pudemos demonstrar que houve uma prevalência de 69% entre a ocorrência de Desordem Crânio Cervical em pacientes portadores de Desordem Temporomandibular; os sintomas de Desordem Temporomandibular que apresentaram correlação com a Desordem Crânio Cervical foram: dor nas articulações temporomandibulares, dor nos músculos masseter espontânea e dor à palpação nos músculos temporais, masseteres e trapézio; o gênero feminino apresentou os maiores índices de Desordem Crânio Cervical em pacientes portadores de Desordem Temporomandibular, o mesmo ocorreu para a faixas etária de 41 a 60 anos e; os testes propostos para a avaliação da Desordem Crânio Cervical foram eficientes / Abstract: The aim of the present study was to determine the prevalence of Cranio SpineDisorders in volunteers presenting Temporomandibular Disorders; correlated signs and symptoms involved in the onset of both diseases, discussing possibilities of associations, assess the possibility of contributing to the develop a good database for diagnosis. 200 volunteers were selected from the screening service at the Piracicaba Dental School, University of Campinas, which were evaluated by the anamnesic questionnaire and clinical exams of the Center of Study and Treatment of the Stomatognathic System Disorders (CETASE) for TMD diagnosis. Volunteers who presented positive signs and symptoms for TMD underwent a new clinical examination for the investigation of the presence of CSD. Our results showed a prevalence of 69% of CSD in volunteers with TMD. Among the major signs and symptoms of TMD related to CSD, we observed statistically significant results for temporomandibular joint pain (p = 0.0168), spontaneous pain for the masseter (p = 0.0049) and pain on palpation to the temporal muscles (p = 0.0016), masseter (p = 0.0052) and trapezius (p = 0121). Physical examinations performed for diagnosis of CSDwere very specific in order to characterize correctly 95.45% of the sample. In conclusion we demonstrated that there was a prevalence of 69% between the occurrence of CSD in patients with TMD; the TMD symptoms that correlated with the CSD were pain in the temporomandibular joints, spontaneous pain in the masseter pain and tenderness in the temporalis muscles, masseter and trapezius muscles; the females had the highest rate of CSD in patients with TMD and the same occurred for the patient aged between 51 and 60 years and; the proposed tests for the evaluation CSD were quite effective / Mestrado / Protese Dental / Mestre em Clínica Odontológica
77

O papel do núcleo pré-mamilar ventral na organização do comportamento agressivo maternal. / Role of the ventral premamillary nucleus in the maternal aggressive behavior.

Cibele Carla Guimarães de Souza 30 June 2011 (has links)
A agressão maternal tem como função preservar a vida da prole. O desenvolvimento desse comportamento depende vastamente do reconhecimento do adversário como uma ameaça potencial e esse reconhecimento envolve a detecção de pistas feromonais. O núcleo pré-mamilar ventral (PMv) é um dos principais alvos do núcleo medial da amígdala, que representa o setor amigdalar crítico para o processamento de pistas feromonais. Desta forma, postulamos que possivelmente o PMv seja sensível às pistas feromonais do macho intruso, servindo como uma possível interface para os sistemas neurais envolvidos na agressão maternal. Neste sentido, inicialmente avaliamos o padrão de ativação do PMv, bem como alguns de seus alvos de projeção, durante o comportamento maternal e durante a agressão maternal. Notamos que tanto o PMv como a maioria de seus alvos principais (tais como, o núcleo posterior da amígdala, a parte posterodorsal do núcleo medial da amígdala, a área hipotalâmica lateral tuberal e a parte ventrolateral do núcleo ventromedial) apresentam um aumento significativo na expressão da proteína Fos durante a agressão maternal. Em seguida, avaliamos o papel do PMv na organização neural do comportamento de agressão maternal, em ratas lactantes portadoras de lesões citotóxicas com NMDA do PMv. Os resultados obtidos neste estudo demonstram que as fêmeas lactantes com lesão no PMv não apresentam qualquer alteração nos parâmetros comportamentais relacionados ao comportamento maternal, mas apresentam uma significante diminuição no comportamento agressivo maternal. Observamos ainda, que a lesão citotóxica do PMv resultou numa drástica diminuição da expressão da proteína Fos em alguns sítios de projeção do PMv que se apresentavam mobilizados durante a agressão maternal (tais como a parte ventrolateral do hipotálamo ventromedial, a área hipotalâmica lateral tuberal e o núcleo pré-óptico medial), sugerindo a participação destes sítios neurais como críticos na expressão do comportamento de agressão maternal. / Maternal aggression is critical to preserve the litters from male intruders, and the pheromonal cues from the males are important to drive such responses. The ventral premamillary nucleus (PMv) is one of the main targets of the medial amygdalar nucleus, and is critically involved in processing pheromonal information. In this regard, in the present study, we investigated whether the PMv would work as a putative interface between the pheromonal processing of the male intruder and the neural sites potentially involved in the expression of maternal aggression. First, we analyzed the pattern of Fos expression in dams expressing aggressive maternal behavior, and found a significant increase in Fos levels in the PMv, as well as, in most of its main targets, such as the posterior amygdalar nucleus, the posterodorsal part of the medial amygdalar nucleus, the tuberal nucleus of the lateral hypothalamic area, and the ventrolateral part of the ventromedial nucleus. Next, we examined how NMDA lesions bilaterally placed in the PMv would interfere in maternal aggression, and found that dams bearing those lesions presented a significant reduction in the expression of aggressive behavior, but showed no alterations on the maternal behavior responses. Moreover, we were able to see that PMv lesions resulted in significant drop in Fos expression in selected PMv targets, namely the tuberal nucleus of the lateral hypothalamic area and the ventrolateral part of the ventromedial nucleus, likely to be critically involved in the expression of the maternal aggression. Overall, the present results support the idea that the PMv is seemingly a key site in the network controlling maternal aggression; on one hand, the nucleus is likely to processes pheromonal cues from the intruder male, and, on the other, it conveys this information to sites critically related to the expression of maternal aggression.
78

Estudo da ação do núcleo pré-mamilar ventral de ratos no controle reprodutivo e em respostas à exposição feromonal. / The role of the ventral premammillary nucleus of rats in the reproductive control and in responses to pheromonal stimulation.

José Donato Júnior 28 November 2008 (has links)
O objetivo do presente trabalho foi investigar a relação do núcleo pré-mamilar ventral (PMV): 1) na regulação do sistema reprodutivo em fêmeas, 2) como mediador dos efeitos da leptina e 3) na resposta à estimulação feromonal. Para tanto, induzimos lesão bilateral do PMV em ratas. Foi observado que a lesão do PMV promove: alteração no ciclo estral e da histologia ovariana; redução dos níveis de estradiol e LH; e supressão de vias neurais que controlam o eixo reprodutivo. Além disso, a lesão do PMV impediu que a administração central de leptina induzisse secreção de LH durante o jejum. Em outros experimentos, realizados em ratos machos, verificou-se que neurônios que sintetizam óxido nítrico no PMV e no núcleo medial da amígdala são ativados em resposta ao odor de conspecíficos, em especial o de fêmeas. Assim, foi demonstrado que o PMV exerce papel relevante na regulação do sistema reprodutivo e media a ação estimulatória da leptina na secreção do LH. Além disso, o PMV faz parte do circuito neural relacionado com a resposta aos feromônios. / The objective of this study was to assess the role played by the ventral premammillary nucleus (PMV): 1) in the regulation of the female reproductive system, 2) as a mediator of the effects of leptin and 3) in response to pheromonal stimulation. For this purpose, we produced bilateral PMV lesions in female rats. We observed that PMV lesion: disrupted the estrous cycle and altered the number of ovarian antral follicles; reduced the estradiol and LH levels; and suppressed neural pathways that control the reproductive axis. We found that lesions of the PMV blocked leptin stimulation of LH secretion during fasting. In another experiment using male rats, we showed that nitric oxide synthesizing neurons in the PMV and medial nucleus of amygdala are activated by conspecific odors, especially female odors. Thus, we showed that PMV plays an important role in the control of females reproductive system and mediates the stimulatory effects of leptin on LH secretion. Also, PMV is part of the neural circuitry related to pheromonal responses.
79

Circuitaria e assinatura neuroquímica das projeções entre a habenula lateral, o núcleo tegmental rostromedial e o núcleo dorsal da rafe. / Circuitry and neurochemical signature of projections between the lateral habenula, the rostromedial tegmental nucleus and the dorsal raphe nucleus.

Chemutai Sego 27 June 2013 (has links)
A habenula lateral (LHb) inibe neurônios dopaminérgicos no mesencéfalo através de um nodo GABAérgico no tegmento mesopontino, o núcleo tegmental rostromedial (RMTg). Ambos a LHb e o RMTg também projetam para o núcleo dorsal da rafe (DR). A organização das projeções da LHb e do RMTg para o DR foi investigada através de injeções de um traçador anterógrado na LHb ou no RMTg e confirmada com injeções de traçadores retrógrados. Para identificar o fenótipo neuroquímico das projeções RMTg-DR, combinamos a hibridização in situ para mRNA de GAD67 com a detecção imunoistoquímica de traçadores retrógrados injetados no DR. Caracterizamos as subdivisões-alvo das projeções RMTg-DR através de dupla-imunofluorescência para o traçador anterógrado injetado no RMTg e serotonina ou o transportador vesicular de glutamato do tipo 3. Detectamos uma projeção focal direta da divisão medial da LHb para a parte caudal do DR. Em contraste, projeções GABAérgicas robustas do RMTg foram direcionadas para uma subdivisão central do DR enriquecida em neurônios presumidamente glutamatérgicos. / The lateral habenula (LHb) inhibits mesencephalic dopamine neurons through a mesopontine GABAergic node, the rostromedial tegmental nucleus (RMTg). Both LHb and RMTg also project to the dorsal raphe nucleus (DR). The organization of LHb and RMTg projections to the DR was investigated using anterograde tracer injections into the LHb or RMTg and confirmed with retrograde tracer injections. To identify the neurochemical phenotype of RMTg-DR projections, we associated in situ hybridization for GAD67 mRNA with immunohistochemical detection of retrograde tracers deposited in the DR. DR target regions of RMTg projections were characterized using double-imunofluorescence techniques for the anterograde tracer deposited into the RMTg and either serotonin or the type 3 vesicular glutamate transporter. We detected a focal direct projection from the medial LHb division to the caudal DR. In contrast the RMTg emits robust GABAergic projections to a central DR subdivision rich in presumptive glutamatergic neurons.
80

Estudo da anatomia endoscópica ventricular em cadáveres humanos brasileiros não fixados para realização de terceiro ventriculostomia / Study of ventricular endoscopic anatomy on Brazilian human cadavers non-fixed for the performance of the third ventriculostomy

Alicia Del Carmen Becerra Romero 27 August 2010 (has links)
INTRODUÇÃO: O objetivo desta pesquisa foi medir, através da endoscopia, o plexo corióideo no forame interventricular e estruturas no assoalho do terceiro ventrículo, bem como a distância entre as artérias comunicantes posteriores e comparar essas variáveis. MÉTODOS: Estudo observacional, prospectivo realizado em 37 cérebros de cadáveres humanos adultos, de ambos os sexos, no Serviço de Verificação de Óbitos da Universidade de São Paulo, em abril de 2008, utilizando neuroendoscópio rígido. As imagens endoscópicas foram gravadas, corrigidas para distorção e mensuradas. A medida macroscópica entre as artérias comunicantes posteriores foi realizada após o estudo endoscópico. RESULTADOS: As medidas do plexo corióideo no forame interventricular, a distância látero-lateral dos corpos mamilares, a distância do recesso do infundíbulo até os corpos mamilares e do triângulo de segurança no túber cinéreo foram 1,71 mm (±0,77 mm), 2,23 mm (±0,74 mm), 3,22 mm (±0,82 mm), 3,69 mm2 (±2,09 mm2), respectivamente. O aspecto do assoalho do terceiro ventrículo e a distância interna dos corpos mamilares foi 84% opaco e 89% ausente, respectivamente. A distância média entre as artérias comunicantes posteriores foi de 12,5 mm (±2,3 mm). Associações entre translucidez do assoalho do terceiro ventrículo com as seguintes variáveis: distância láterolateral e distância interna dos corpos mamilares, assim como idade, foram identificadas. CONCLUSÕES: Até esta pesquisa, não existiam medidas sobre o plexo corióideo no forame interventricular e distância entre as artérias comunicantes posteriores na região dos corpos mamilares. As variáveis restantes, quando comparadas com a literatura, foram em maior número e em cérebros normais / INTRODUCTION: the objective of this research was to measure, through endoscopy, the interventricular foramen choroid plexus and the third ventricle floor structures, as well the distance between the communicating posterior arteries and compare these variables. METHODS: an observational, prospective study was conducted in 37 brains of adult human cadavers, of both sexes at the Death Check Unit of the University of São Paulo, in April 2008 by means of the rigid neuroendoscope. The endoscopic images were recorded, corrected for distortion and measured. The macroscopic measure between the communicating posterior arteries was performed after the endoscopic study. RESULTS: The measures of the interventricular foramen choroid plexus, the latero-lateral distance of mammillary bodies, the distance from the infundibular recess to the mammillary bodies, safety triangle in the tuber cinereum were 1.71 mm (±0.77 mm), 2.23 mm (±0.74 mm), 3.22 mm (±0.82 mm), 3.69 mm2 (±2.09 mm2), respectively. The aspect of the third ventricle floor and the internal distance of the mammillary bodies was 84% opaque and 89% absent, respectively. The mean distance between the communicating posterior arteries was 12.5 mm (±2.3 mm). Associations between the translucent floor of the third ventricle with the following variables: latero-lateral distance and internal distance of the mammillary bodies, as well as age were identified. CONCLUSIONS: Up this research, there was no account on the measures of the interventricular foramen choroid plexus and the distance between communicating posterior arteries at the level of the mammillary bodies. The remaining variables were in greater number and in normal brains, as compared with the literature

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