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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.
21

Intestinal versus hepatic CYP3A-dependent first-pass metabolism /

Paine, Mary F., January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves 171-191).
22

Mechanisms and pathways for proton transfer in cytochrome-c oxidase

Ädelroth, Pia. January 1998 (has links)
Thesis (doctoral)--Göteborg University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.
23

Mechanisms and pathways for proton transfer in cytochrome-c oxidase

Ädelroth, Pia. January 1998 (has links)
Thesis (doctoral)--Göteborg University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.
24

Cytochrome c oxidase subunit Vb interacts with human androgen receptor : a potential mechanism for neuronotoxicity in spinobulbar muscular atrophy

Beauchemin, Annie January 2000 (has links)
No description available.
25

Gene Flow and Dispersal of the Flatworm, <em>Polycelis coronata</em>: A Multiscale Analysis

Moore, Jeffrey N. 02 December 2010 (has links) (PDF)
We determined genetic variance and gene flow across multiple scales (reaches, headwater segments, and catchments) to examine the dispersal ability of the flatworm Polycelis coronata along the Wasatch Mountains of Utah. Multiple models predict patterns of genetic differentiation in stream invertebrates based on dispersal traits and the spatial connectivity of the habitat. The stream hierarchy model predicts genetic differentiation to be low and gene flow to be high between reaches nested in segments, moderate among segments within catchments, and differentiation to be highest and gene flow lowest among catchments, whereas the headwater model predicts the greatest differentiation between headwater segments. Our objective was to determine which model best described genetic patterns observed in P. coronata. Using a nested hierarchical sampling design ensured that if limitations to dispersal had an effect on genetic differentiation, we would be able to identify at what scale these processes operate. We hypothesized genetic variation would be small within headwater segments and reach maximum levels between headwater segments with no increase in differentiation with increasing distance between headwater patches or between drainages. We do not expect high dispersal along the stream network or across the terrestrial environment (actively or passively).We generated DNA sequence data (mitochondrial COI) from 50 sites nested within 24 segments, which were nested in four adjacent catchments. We identified 134 haplotypes from 506 individuals using a 763 bp fragment of mtDNA. Genetic patterns did not conform to the SH model. Evidence from one drainage (Provo River) was consistent with the headwater model. However, high differentiation within sites suggested that the genetic patterns we uncovered may be representative of high ancestral polymorphism among pre-fragmented populations that were historically widespread. Large effective population sizes and no evidence of bottleneck events suggest incomplete lineage cannot be discounted as an explanation of high differentiation at the smallest scales.
26

Phylogeography of Marine Meiofaunal Nemerteans of the Ototyphlonemertes Fila Species Complex

Tulchinsky, Alexander 01 January 2006 (has links)
Morphological conservatism combined with intraspecific variability has obstructed studies of speciation and species boundaries among marine meiofauna. Ototyphlonemertes is a genus of meiofaunal nemerteans inhabiting the interstitial spaces of marine sediments. Its members lack pelagic larvae and dispersal potential is believed to be poor. A phylogeographic study of Ototyphlonemertes fila is presented using mitochondrial (cox3) and nuclear (ISSR) molecular markers. Deep genetic divergence (approximately 18% in cox3) was observed between sympatric mitochondrial lineages in Florida. This divergence was reflected in the nuclear marker as well, suggesting the presence of two cryptic species. The first contains Florida and New England populations separated by 3% cox3 sequence divergence and showing no evidence of ongoing gene flow. The second contains two codistributed mitochondria1 clades in Florida separated by 3% cox3 sequence divergence and showing exchange of nuclear alleles. Surprisingly, relatively little fine-scale structuring was found, suggesting that passive dispersal is significant over moderate geographical distances.
27

Caracterização morfométrica e molecular de Anastrepha bistrigata Bezzi e Anastrepha striata Schiner (Diptera: Tephritidae) / Morphometric and molecular characterization of Anastrepha bistrigata Bezzi and Anastrepha striata Schiner (Diptera: Tephritidae)

Silva, Tibério Graco Araújo da 18 August 2008 (has links)
Considerando-se a semelhança morfológica e ocorrência simpátrica de Anastrepha striata Schiner e Anastrepha bistrigata Bezzi, este trabalho propôs identificar formas para melhor caracterizá-las através de análises morfométricas do acúleo e asas de populações simpátricas e alopátricas dessas espécies, e molecular, por meio da análise de seqüências parciais do gene da citocromo oxidase I (COI). O trabalho também teve por objetivo desenvolver iniciadores espécie-específicos que possam vir a ser utilizados em estudos ecológicos em regiões em que ambas as espécies ocorram simpatricamente. As populações analisadas A. striata (seis populações) e A. bistrigata (duas populações) foram provenientes de diferentes regiões do Brasil, Colômbia e Bolívia. Para os estudos morfométricos, os acúleos e asas foram montados em lâminas para captura e análise de imagens com auxílio de câmera fotográfica acoplada ao microscópio estereoscópico, utilizando-se de software apropriado. Foram traçados e mensurados oito segmentos no acúleo e 16 na asa direita de cada indivíduo, obtendo-se assim as medidas nas quais se basearam as análises. Nos estudos moleculares, os produtos de amplificação obtidos para a COI foram seqüenciados e analisados para o estudo da caracterização molecular das diferentes populações desses insetos e desenvolvimento de iniciadores espécie-específicos. Os resultados indicam a existência clara de distinção morfométrica entre as duas espécies e confirmaram as identificações baseadas na largura e comprimento do acúleo. Os dados morfométricos mostraram também a ausência de padrões geográficos distintos entre as populações de A. striata e A. bistrigata. A. striata apresentou maior variação morfométrica entre suas populações quando comparada à diferenciação encontrada para A.bistrigata. Nas duas espécies, populações encontradas em maiores altitudes apresentaram maiores dimensões. A análise de nucleotídeos da seqüência da COI obtida para as populações de A. striata em questão indicou a ocorrência de alta similaridade entre as mesmas. As análises realizadas também indicaram que a divergência genética encontrada no fragmento da COI analisado para as diferentes populações de A. striata não permitiu o agrupamento de acordo com a distribuição geográfica dessas populações. A análise do fragmento do gene da COI permitiu o desenvolvimento de iniciadores com divergência suficiente entre as espécies em questão para permitir a amplificação de porção específica do gene da COI, que possibilita a diferenciação entre as mesmas. Os iniciadores propostos reúnem características que permitem a sua utilização em reações de PCR multiplex para a diferenciação entre espécimes de ambas as espécies. / Because of the fact that Anastrepha striata Schiner and Anastrepha bistrigata Bezzi are very similar morphologically and may also occur sympatrically, this study aimed to propose different ways to characterize them by using wing and aculeus morphometry, and mitochondrial DNA sequencing. This work also aimed to develop species-specific primers to allow for the differentiation between both species in sympatric areas. Six A. striata and two A. bistrigata populations were obtained from different regions from Brazil, Colombia and Bolivia. Specimens from different populations had their aculeus and wings removed and slide mounted for image acquisition under a stereomicroscope and morphometric analysis. Data collection for morphometry were taken for each specimen on eight segments of the aculeus and on 16 of the right wing. The molecular characterization consisted of the sequencing and analysis of a fragment of the cytochrome oxidase I (COI) gene, and the development of species-specific primers. Morphometry did not indicate any consistent variation to allow for geographical characterization of different populations, but indicated A. striata and A. bistrigata are consistently different morphologically. Populations of either species from higher altitudes were larger than the ones at lower altitudes, and A. striata displayed a much higher intraespecific variation in morphology than A.bistrigata. COI nucleotide sequences for A. striata were very similar among the populations studied, and the molecular analysis did not yield groups that were related geographically. The COI analysis allowed the development of a set of species-specific primers that were divergent enough to allow for the discrimination of A. striata and A. bistrigata in multiplex PCR reactions.
28

An?lise gen?tica e fenot?pica de macacos-prego da Ilha da Marambaia, Mangaratiba, Rio de Janeiro / Genetic and phenotypic analysis of capuchin monkeys from Ilha da Marambaia, Mangaratiba, Rio de Janeiro

PENEDO, Diego Mattos 26 February 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-22T20:14:46Z No. of bitstreams: 1 2016 - Diego Mattos Penedo.pdf: 4081734 bytes, checksum: 3e13fd4d6f8b8c4d8d31a05fefa2ba14 (MD5) / Made available in DSpace on 2017-02-22T20:14:46Z (GMT). No. of bitstreams: 1 2016 - Diego Mattos Penedo.pdf: 4081734 bytes, checksum: 3e13fd4d6f8b8c4d8d31a05fefa2ba14 (MD5) Previous issue date: 2016-02-26 / CAPES / Several studies have been conducted with capuchin monkeys (Sapajus and Cebus) in order to understand their evolutionary histories by South and Central America. Genetic analysis, in association with the coat coloration, assist in the identification of the relationships between species and show the diversity presented by both genera. In Brazil, Sapajus species are predominantly distributed, being S. nigritus endemic to the Atlantic Forest and characteristic of southeast. At Ilha da Marambaia, an important area with forest remaining in the state of Rio de Janeiro, there is a population of capuchin monkeys, but without previous study. The objective of this study was to characterize the population of capuchin monkeys at this region through phenotypic and genetic analyzes, including the coat coloration, the sequencing of the mitochondrial gene cytochrome oxidase II and the evaluation of karyotype with conventional staining and C-band. Interviews with residents and military personnel in the region, were also carried out, in order to identify the possible origin and isolation of the primates. Twelve specimens, eight males and four females, were analyzed. The coat features were consistent with that described for S. nigritus, with coloration varying from brown to blackish on the back, limbs, tail and top of the head, in addition to yellow chest and face with white or light yellow, contrasting. Tufts at the top of the head were seen in adults, being greater in females. The analysis of mitochondrial gene revealed closer proximity of this population with S. xanthosternos, which occurs at Bahia, and then with S. cay that occurs in parts of Brazil and Paraguay. The greatest divergence was in relation to the population of S. nigritus in Argentina. The karyotype was consistent with that described for Sapajus species, with 2n = 54 (XX or XY), although the morphology of the sex chromosome Y, submetacentric, was different from that commonly described in the literature (acrocentric). Presented intercalary C-band the chromosome pairs 4, 11, 12 and 17. The par 11 presented three polymorphisms, all interstitial to euchromatin and diversified from each other by deletion and inversion processes. The pattern of this pair is different from that described, as a small acrocentric, to S. nigritus in populations of Argentina, with banding similar to that considered specific for S. xanthosternos. According to the survey, the population of primates seems to be native of the island and is currently isolated. According to the genetic divergences found, the population of Ilha da Marambaia may have maintained ancestral characteristics. The C-band pattern of the pair 11 indicates that the polymorphism described for populations of Argentina does not correspond to the entire distribution of S. nigritus. These data may help to understand the diversity and evolution of Sapajus, since this would have radiated from southeastern Brazil. Further studies with populations from other regions of Rio de Janeiro are needed to verify the C-band pattern presented for the pair 11 as well as the genetic relationships demonstrated by the mitochondrial gene for the population of Ilha da Marambaia. / Diversos estudos v?m sendo realizados com macacos-prego e caiararas (Sapajus e Cebus) de modo a entender suas hist?rias evolutivas pelas Am?ricas do Sul e Central. An?lises gen?ticas, em associa??o ?s caracter?sticas de pelagem, auxiliam na identifica??o das rela??es entre as esp?cies e evidenciam a diversidade apresentada por ambos os g?neros. No Brasil, est?o distribu?das predominantemente as esp?cies de Sapajus, sendo S. nigritus end?mica de Mata Atl?ntica e caracter?stica do sudeste. Na Ilha da Marambaia, importante ?rea com remanescente florestal no estado do Rio de Janeiro, existe uma popula??o de macacos-prego, sem nenhum estudo anterior. O objetivo deste trabalho foi caracterizar a popula??o de macacos-prego dessa regi?o atrav?s de an?lises fenot?picas e gen?ticas, incluindo o padr?o de pelagem, o sequenciamento do gene mitocondrial Citocromo Oxidase II e a avalia??o do cari?tipo com colora??o convencional e bandamento de heterocromatina constitutiva (banda C). Foram realizadas, tamb?m, entrevistas com moradores e militares da regi?o, de modo a identificar a poss?vel origem e isolamento dos primatas. Foram analisados doze esp?cimes, oito machos e quatro f?meas. As caracter?sticas de pelagem coincidiram, de modo geral, com descrito para S. nigritus, sendo observada colora??o variando de marrom a enegrecida no dorso, membros, cauda e topo da cabe?a, al?m de peito amarelo e face branca ou amarelo-clara, contrastante. Tufos de pelos no topo da cabe?a foram observados nos adultos, sendo maiores nas f?meas. A an?lise do gene mitocondrial revelou maior proximidade da popula??o da ilha com S. xanthosternos, que ocorre na Bahia, e em seguida com S. cay, que ocorre em parte do Brasil e no Paraguai. A maior diverg?ncia apresentada foi em rela??o a popula??es de S. nigritus da Argentina. A an?lise do cari?tipo revelou padr?o condizente com as esp?cies de Sapajus, com 2n = 54 (XX ou XY), embora a morfologia do cromossomo sexual Y, submetac?ntrica, fosse divergente do comumente descrito na literatura (acroc?ntrica). Apresentaram banda C intercalar os pares cromoss?micos 4, 11, 12 e 17. O par 11 mostrou-se com tr?s polimorfismos, todos intercalares e diversificados entre si por processos de dele??o e invers?o. O padr?o deste par foi divergente do descrito, como um pequeno acroc?ntrico, para S. nigritus em popula??es da Argentina, apresentando bandamento semelhante ao considerado espec?fico de S. xanthosternos. Segundo o levantamento realizado, a popula??o de primatas parece ser natural da ilha, estando provavelmente isolada. De acordo com as diverg?ncias gen?ticas encontradas, a popula??o da Ilha da Marambaia pode ter conservado caracter?sticas ancestrais. O padr?o de banda C do par 11 indica que o polimorfismo descrito para popula??es da Argentina pode n?o corresponder a toda a distribui??o de S. nigritus. Estes dados podem auxiliar no entendimento da diversidade e evolu??o das esp?cies de Sapajus, uma vez que este teria irradiado a partir do sudeste brasileiro. Novos estudos com popula??es de outras regi?es do Rio de Janeiro s?o necess?rios para se averiguar o padr?o de bandamento de heterocromatina apresentada para o par 11, bem como as rela??es gen?ticas demonstradas pelo sequenciamento do gene mitocondrial para a popula??o da Ilha da Marambaia.
29

Variabilidade populacional em manguezais: análises moleculares e morfológicas em caranguejos Brachyura (Crustacea: Decapoda) / Population variability in mangroves: molecular and morphological analyses in Brachyura crabs (Crustacea: Decapoda)

Buranelli, Raquel Corrêa 18 March 2016 (has links)
A análise da estruturação populacional de espécies codistribuídas permite a comparação de padrões de estruturação, fornecendo informações acerca dos fatores que influenciam a diferenciação em espécies pertencentes ao mesmo ecossistema. Este projeto teve como objetivo principal analisar a variabilidade intraespecífica em caranguejos habitantes de manguezais, codistribuídos ao longo do Oceano Atlântico Ocidental, por meio de ferramentas moleculares e morfológicas, visando testar a hipótese de elevada estruturação populacional em manguezais. Para este fim, cinco espécies foram utilizadas como modelo (Aratus pisonii, Goniopsis cruentata, Sesarma rectum, Uca thayeri e Ucides cordatus) e avaliadas por meio de marcadores mitocondriais COI e 16S e nuclear H3 e análises morfológicas comparativas e de morfometria. Os dados moleculares revelaram dois padrões, indicando elevada estruturação populacional para as espécies A. pisonii e U. thayeri e ausência de estruturação para G. cruentata, S. rectum e U. cordatus. Os dados morfológicos, no entanto, não acompanham esses padrões, já que não foram encontradas diferenças morfológicas ou morfométricas associadas aos grupos evidenciados pelas análises moleculares. A ausência de fluxo gênico entre regiões para algumas espécies deve-se, muito provavelmente, à existência de fatores que não se limitam ao isolamento por distância, mas também devido a diferenças na duração do estágio larval e a diferenças bruscas em alguns fatores abióticos, como a salinidade, por exemplo, que, associados às diferentes características do desenvolvimento larval de cada espécie, culminam na existência de estruturas populacionais diferentes. Além disso, os padrões de diferenciação genética observados concordam com os cenários biogeográficos propostos para o Atlântico Ocidental, no qual mudanças e flutuações geológicas, climáticas e oceanográficas, resultantes do fechamento do Istmo do Panamá e de ciclos glaciais na América do Norte, promoveram divergência genética. / The analysis of population structure of codistributed species allows the comparison of patterns of population structuring, providing information on the factors that influence the differentiation in species belonging to the same ecosystem. This project aimed to analyze the intraspecific variability of crabs inhabiting mangroves, codistributed along the western Atlantic Ocean, by means of molecular and morphological tools, in order to test the hypothesis of high populational structure in mangroves. The genetic variability of five species used as models (Aratus pisonii, Goniopsis cruentata, Sesarma rectum, Uca thayeri and Ucides cordatus) was assessed using the mitochondrial genes COI and 16S and the nuclear H3 and comparative morphological analysis and morphometry were performed. The molecular data revealed two patterns, indicating high population structure for the species A. pisonii and U. thayeri and absence of structure for G. cruentata, S. rectum and U. cordatus. The morphological data, however, do not follow these patterns, because there were no morphological or morphometric differences associated with the groups evidenced by the molecular analyzes. Possibly the absence of gene flow between regions for some species is due to factors not limited to isolation by distance, but also because of differences in the larval stage duration and in withstanding some abiotic factors, such as salinity. These factors associated with different characteristics of larval development can culminate in differences on population structure. In addition, the genetic differentiation patterns observed agree with biogeographical scenarios proposed for the western Atlantic, where geological, climate and oceanographic fluctuations, resulting from the Isthmus of Panama closure and cyclical glaciation in North America, promoted genetic divergence.
30

Functional neural networks underlying latent inhibition and the effects of the metabolic enhancer methylene blue

Puga, Frank 02 December 2010 (has links)
The present research reports the first comprehensive map of brain networks underlying latent inhibition learning, the first application of structural equation modeling to cytochrome oxidase data, and the first effects of methylene blue, a known metabolic enhancer, on latent inhibition. In latent inhibition, repeated exposure to a stimulus results in a latent form of learning that inhibits subsequent associations with that stimulus. As neuronal energy demand to form learned associations changes, so does the induction of the respiratory enzyme cytochrome oxidase. Therefore, cytochrome oxidase can be used as an endpoint metabolic marker of the effects of experience on regional brain metabolic capacity. Quantitative cytochrome oxidase histochemistry was used to map brain regions in mice trained on a tone-footshock fear conditioning paradigm with either tone preexposure (latent inhibition), conditioning only (acquisition), conditioning followed by tone alone (extinction), or no handling or conditioning (naïve). In normal latent inhibition, the ventral cochlear nucleus, medial geniculate, CA1 hippocampus, and perirhinal cortex showed modified metabolic capacity due to latent inhibition. Structural equation modeling was used to determine the causal influences in an anatomical network of these regions and others thought to mediate latent inhibition, including the accumbens and entorhinal cortex. An uncoupling of ascending influences between auditory regions was observed in latent inhibition. There was also a reduced influence on the accumbens from the perirhinal cortex in both latent inhibition and extinction. These results suggest a specific network with a neural mechanism of latent inhibition that involves sensory gating, as evidenced by modifications in metabolic capacity, effective connectivity between auditory regions, and reduced hippocampal influence on the accumbens. The effects of methylene blue on disrupted latent inhibition were also investigated. Reduced tone-alone presentations disrupted the latent inhibition effect and led to an increase in freezing behavior. Repeated low-dose administration of methylene blue decreased freezing levels and facilitated the disrupted latent inhibition effect. Methylene blue administration also resulted in changes in metabolic capacity in limbic and cortical regions. A unique functional neural network was found in methylene blue-restored latent inhibition that emphasized sensory gating of auditory information, attention processing, and cortical inhibition of behavior. / text

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