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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.
11

Aspects of Fathead Minnow Reproductive Behavior

Pyron, Mark 05 1900 (has links)
Following a study of normal reproductive behavior of fathead minnows, Pimephales promelas, experiments were conducted to determine the stability/variability of behavior by sexually mature, territorial males under a variety of manipulated conditions. Collectively, these experiments indicate that although the individual behaviors of fathead minnows appear to be quite variable, the overall process, reproductive behavior, is stable.
12

Differential stability of spawning microhabitats of warmwater stream fishes

Smith, Ryan Kennerly 05 June 1999 (has links)
I investigated streambed stability in spawning microhabitats of warmwater fishes in the upper Roanoke River, Virginia. Spawning microhabitats used by four reproductive guilds (egg-clusterers, mound-builders, egg-buriers, and pit-builders) were identified and ranges of 15 microhabitat variables used by each guild were compared to available microhabitat conditions to investigate habitat selection. Habitat usage by egg-clusterers was most characterized by selection for spawning rocks in the cobble size range, substrate roughness elements in the cobble to boulder size range, high roughness Reynolds number and moderate water column velocity. The mound-building bluehead chub (Nocomis leptocephalus) was distinct in its selection of substrate in the small gravel range, low water velocity and non-turbulent flow. Egg-buriers were the least distinct of the four guilds, exhibiting much variation in habitat use among the component species. However, all species used areas with small substrate (sand to gravel range), high velocity, and high turbulence. The pit-building central stoneroller (Campostoma anomalum) was distinct in its usage of areas with high velocity and turbulence, gravel sized substrate, and low embeddedness. Stability of each guild's spawning microhabitats was empirically evaluated through analysis of tracer particle movement and repeated surveying of bed elevation along stream transects. Logistic regression equations developed from tracer particle data predicted that microhabitats selected by egg-clusterers are among the most stable of all available habitats during high flows. Microhabitats utilized by mound-builders, egg-buriers, and pit-builders are predicted to be less stable. Repeat transect surveying corroborates model predictions in that egg-burier habitats experienced changes in bed elevation in high flows, while egg-clusterer habitats did not. / Master of Science
13

Composição, abundância e aspectos reprodutivos das espécies de peixes do reservatório Álvaro de Souza Lima (Bariri, SP) e sua relação com as características ambientais do sistema / Composition, abundance and reproductive aspects of fishes from Álvaro de Souza Lima reservoir (Bariri, SP) and relationships with environmental factors of the system

Marciano, Fernanda Teixeira e 05 December 2005 (has links)
A construção dos reservatórios implica em alterações de caráter social, econômico e biológico, que podem interferir de maneira espacial e/ou temporal sobre o ecossistema. Neste contexto, as características das comunidades ícticas têm sido utilizadas para avaliação da degradação ambiental, por serem sensíveis indicadoras de estresses diretos ou indiretos de todo ecossistema. Desta forma, com o intuito de analisar a comunidade íctica do reservatório de Bariri segundo a composição, a diversidade, a dominância das espécies e os aspectos reprodutivos das mesmas, fez-se necessário: 1. Calcular o índice de diversidade (Shannon), a riqueza e a abundância das trinta e sete espécies de peixes coletadas; 2. Aplicar o índice ponderal de dominância; 3. Determinar a estrutura das populações de peixes em relação à composição em tamanho, sexo e proporção sexual; 4. Determinar a relação peso x comprimento e os fatores de condição das espécies; 5. Estabelecer uma escala de maturação e verificar, através da curva de maturação, o período reprodutivo e o tamanho do menor indivíduo em 1ª maturação para cada espécie dominante; 6. Identificar quais as espécies exóticas presentes neste sistema e se a introdução de Plagioscion squamosissimus e Cichla cf. monoculus, em especial, exerciam algum impacto sobre a dinâmica populacional das demais espécies e 7. Verificar quais os fatores ambientais que propiciaram o sucesso reprodutivo das espécies dominantes e de Plagioscion squamosissimus e Cichla cf. monoculus. Assim sendo, concluiu-se que a diversidade ictiofaunística revelou homogeneidade entre as quatro épocas de coleta e que as espécies parecem sofrer influência direta de algumas variáveis limnológicas. Verificou-se ainda, que a ictiofauna é composta por seis espécies dominantes, as quais foram classificadas em três estádios de maturação gonadal, possibilitando verificar que o crescimento era do tipo isométrico para todas as espécies dominantes, sem dimorfismo sexual. Até o presente momento não se pode considerar que, para este reservatório, a introdução das espécies Plagioscion squamosissimus e Cichla cf. monoculus tenham causado efeito aparente sobre as espécies nativas, diminuindo o tamanho da população destas ou ainda alterando a estrutura etária das demais espécies. / The construction of reservoirs cause changes of social, economic and biological alterations, that can interfere spatially and/or temporally upon the ecosystem. In this context, the characteristics of fish communities have been used in order to evaluate environmental degradation, because they are good indicators of direct and indirect stresses in the whole ecosystem. Therefore, aiming to analyze the fish community of Bariri reservoir regarding the species composition, diversity and dominance of species and also their reproductive aspects, it was necessary: 1. Calculate the diversity index (Shannon), the species richness and the abundance of the 37 species collected; 2. Apply the ponderal dominance index; 3. To determine fish population structure regarding size structure, sex and sex ratio; 4. To determine length-weight relationships and their condition factor; 5. Establish a scale of maturation and to verify using the maturation curve, the reproductive period and the minimum individual size in the first reproduction, for each dominant species; 6. Identify which are the exotic species present in the system and to verify if the introduction of Plagioscion squamosissimus and Cichla cf. monoculus, especially had some impact on the population dynamics of other species, and 7. Verify which environmental factors have determined the reproductive success of the dominant species and Plagioscion squamosissimus and Cichla cf. monoculus. It was concluded that fish diversity was homogeneous among the four sampling periods and that the species seem to suffer the direct influence of some limnological variables. It was also verified that the fish community was composed by six dominant species, which were classified in three gonad maturation stages, allowing to verify that growth was isometric for all the dominant species, without sexual dimorphism. Up to now, for this reservoir, it was not possible to consider that the introduction of the species Plagioscion squamosissimus and Cichla cf. monoculus had an apparent effect on the native species of fish, decreasing their population size or changing the age structure of the other species.
14

Atividade reprodutiva da ictiofauna acompanhante explorada pela pesca de emalhe no litoral central de Alagoas / Reproductive activity of Bycatch exploited by driftnet fishing in the coast of Alagoas

Lima, Cibele Tiburtino Cavalcante de 28 March 2011 (has links)
A characterization reproductive of fish study may help in determination of recurring patterns of behavior and to facilitate response predictions to demographic disturbance in the spatial and temporal scales in determined zoogeographical area. Therefore, the objective was to identify the reproductive aspects of bycatch exploited by driftnet fishing community of Jaraguá, Maceió / Alagoas. To that end, samples were collected in two boats per month from December 2009 to November 2010. 2149 fish, 51 species and 25 families were collected, being the most abundant family Haemulidae. The high selectivity of gill nets resulted in a low range of total length (150-601 mm). Among the most abundant species (n &#8805; 30) the number of females was significantly higher (p <0.05), except B. marinus. We suggest the occurrence of split spawning for A. vulpes, B. marinus, C. chrysurus, C. nobilis, E. alletteratus, H. parrai, H. plumieri, O. oglinum, O. ruber and P. corvinaeformis. Recorded little fluctuation of the values of Gonadosomatic Index, Condition Factor and Repletion index, per season, which agrees with the expected for tropical regions. A portion of young individuals of E. alletteratus, A. vulpes and C. crysos indicates that driftnet fishing in the area does not meet any standard of maturity in relation to the capture of species. Identified were three groups of species, according to results of PCA, explained mainly by the size at first maturity, and comprimeto total gonad weight, contained in factor 1 explains 50.74% variance. The variance index of reproductive activity values suggest that P.maculatus, C. crysos and O. ruber species are most vulnerable to the impact of fishing on reproductive activity. Thus, these fisheries are at risk of impact on the reproductive process of harvested species, highlighting the need to implement regulatory measures for fisheries with gillnets in Alagoas. / Fundação de Amparo a Pesquisa do Estado de Alagoas / A caracterização reprodutiva dos peixes pode ajudar na determinação de padrões recorrentes e facilitar previsões sobre respostas a perturbações demográficas nas escalas espaciais e temporais em determinada dada área zoogeográfica. Diante disso, o objetivo do trabalho foi identificar aspectos reprodutivos da ictiofauna acompanhante explotada pela pesca de emalhe da frota artesanal de Jaraguá, Maceió/Alagoas. Para tanto, coletas mensais do desembarque foram realizadas entre dezembro de 2009 e novembro de 2010. Foram coletados 2149 peixes, de 51 espécies e 24 famílias, sendo Haemulidae a família mais abundante. A alta seletividade da rede de emalhe resultou em uma amplitude estreita de comprimento total (150 - 601 mm). Dentre as espécies mais abundantes (n&#8805;30) o número de fêmeas foi significativamente maior (p<0,05), com exceção de B. marinus. Sugere-se a ocorrência de desova parcelada para A. vulpes, B. marinus, C. chrysurus, C. nobilis, E. alletteratus, H. parrai, H. plumieri, O. oglinum, O. ruber e P. corvinaeformis. Registrou-se pouca flutuação sazonal dos valores do Índice Gonadossomático, Fator de Condição e Índice de Repleção Estomacal, fato característico das regiões tropicais. Uma parcela de indivíduos jovens de E. alletteratus, A. vulpes e C. crysos indica que as capturas da pesca de emalhe na área não atende a nenhum padrão relacionado à maturidade das espécies. Identificaram-se três grupos de espécies, conforme os resultados da PCA, explicados principalmente pelo tamanho de primeira maturação, comprimento total e peso das gônadas, contidos no fator 1que explica 50,74% da variância. As variações do índice de atividade reprodutiva sugerem que O. ruber, C. crysos e P. maculatus são as espécies mais vulneráveis ao impacto da pesca. Sendo assim, estas pescarias apresentam risco de impacto sobre o processo reprodutivo das espécies capturadas, destacando a necessidade da implantação de medidas reguladoras das pescarias com rede de emalhe em Alagoas.
15

Indução à reprodução e desenvolvimento embrionário e larval do ciclídeo acará-açu Astronotus ocellatus (Agassiz, 1831)

Paes, Maria do Carmo Faria [UNESP] 26 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-26Bitstream added on 2014-06-13T19:48:39Z : No. of bitstreams: 1 paes_mcf_me_jabo.pdf: 990222 bytes, checksum: f08cd87c9c978169ebdb4fdbd5287e5d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O Astronotus ocellatus é originário da Bacia Amazônica, climatizado e disseminado, desde 1938, em açudes e rios do Nordeste brasileiro, pelo Departamento Nacional de Obras Contra as Secas. Trata-se de um peixe de grande potencial, devido a características adequadas para pesca esportiva, cultivado como ornamental e com uma carne saborosa e apreciada pela população do Norte e Nordeste do Brasil. Existem na literatura atual poucos estudos a respeito da biologia reprodutiva dessa espécie. Embora seja de desova parcelada e se reproduza bem em cativeiro, estudos de reprodução artificial têm suma importância para diversas pesquisas de biologia e desenvolvimento embrionário, cujos eventos devem ser acompanhados numa faixa de tempo conhecida e assim contribuir para uma melhor compreensão do cultivo, manejo e controle da espécie. O presente trabalho teve por objetivo avaliar a resposta do Astronotus ocellatus a aplicação de dois hormônios estimuladores de reprodução (gonadodropina coriônica humana - HCG e extrato de hipófise de carpa - EHC) e estudar a estrutura, ultraestrutura e morfometria de seus ovos e larvas. Foram utilizados 16 casais de reprodutores pertencentes ao Centro de Aqüicultura da Universidade Estadual Paulista, Campus de Jaboticabal (SP) e quatro desovas ocorridas naturalmente nos viveiros. Observouse que cinco das dezesseis fêmeas responderam ao estímulo hormonal, sendo três com HCG e duas com EHC. Dos machos, apenas um respondeu positivamente ao HCG. O acará-açu possui ovos demersais, adesivos, pouco resistentes ao tato, de formato ovóide pouco acentuado. “In vivo” apresentaram coloração amarelada, quando fertilizados, e branca opaca, quando não fertilizados, com grande esfera vitelina e pequeno espaço perivitelino. As desovas apresentaram ovos com valores médios variando de 1,75±0,056 a... / Astronotus ocellatus is a fish from the Amazon Basin, adapted and widely reared since 1938 in ponds and rivers of Brazilian northeast region by the Departamento Nacional de Obras Contra as Secas. This fish has a great potential due to appropriate characteristics for sporting fishing, reared as ornamental and owning a very tasty meat being appreciate by the people in north and northeast regions of Brazil. Despite having all these adjectives for aquaculture there are a few studies about reproductive biology of this species. Although spawning does not occur at once and reproduction in captivity is well successful, studies about artificial reproduction are extremely important for several researches in biology and early embryonic development of which events must be followed in a known lack of time and like this to contribute for a better understanding of rear conditions, management and control of the species. Therefore, this present research aimed to assess the Astronotus ocellatus responses to administration of two kinds of reproductive hormones (Human Chorionic Gonadotropin - HCG and carp hypophysis extract – CHE) and studying the structure, ultrastructure and morphometry of its eggs and larvae. Sixteen couples from Centro de Aqüicultura of Universidade Estadual Paulista, Campus of Jaboticabal (SP) and four spawnings occurred naturally in ponds were also catched. Five of sixteen females responded to hormonal stimuli, three of them with HCG and two with CHE. In relation to males, only one responded favorably to HCG. Acará-açu females have demersal and adhesive eggs, somewhat resistant to the touch, discreet egg shape-like, yellowish colour “in vivo” and when fertilized and white opalescent without fertilization, with a large vitelline sphere and a small space between yolk and chorion. The spawnings presented eggs with average values of 1,75±0,056 ...(Complete abstract click electronic access below)
16

Transplante de espermatogônias tronco em peixes teleósteos, utilizando como modelo experimental a carpa comum (Cyprinus carpio) / Spermatogonial stem cells transplantation in teleost fish, using the common carp (Cyprinus carpio) as experimental model

Arias Vigoya, Angel Andrés [UNESP] 08 December 2016 (has links)
Submitted by ANGEL ANDRÉS ARIAS VIGOYA null (lakotah1@gmail.com) on 2017-01-25T17:53:42Z No. of bitstreams: 1 TESE VERSAO DEFINITIVA.pdf: 6803879 bytes, checksum: 2803b2bfb33863aee3dc638d6b31456b (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-01-27T13:30:27Z (GMT) No. of bitstreams: 1 ariasvigoya_aa_dr_jabo.pdf: 6803879 bytes, checksum: 2803b2bfb33863aee3dc638d6b31456b (MD5) / Made available in DSpace on 2017-01-27T13:30:27Z (GMT). No. of bitstreams: 1 ariasvigoya_aa_dr_jabo.pdf: 6803879 bytes, checksum: 2803b2bfb33863aee3dc638d6b31456b (MD5) Previous issue date: 2016-12-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nos vertebrados, a espermatogênese é um processo de desenvolvimento celular altamente conservado e organizado, no qual uma pequena população de espermatogônias tronco produz continuamente milhões de espermatozóides, os quais são os responsáveis pela propagação do genótipo dos machos. Este processo é sustentado pelas espermatogônias tronco através da sua capacidade de auto-renovação e diferenciação. Vários aspectos relacionados com a regulação da atividade e fisiologia das espermatogônias tronco são ainda desconhecidos nos peixes teleósteos. Portanto, a técnica de transplante de células germinativas torna-se uma poderosa abordagem para melhorar o conhecimento da biologia das espermatogônias tronco e da espermatogênese. Resumidamente, a técnica envolve a transferência de células germinativas isoladas de um doador fértil para os testículos de um receptor estéril, e as células transplantadas são capazes de restaurar a gametogênese do receptor. Neste contexto, realizamos uma caracterização morfológica e estereológica dos diferentes tipos de células encontradas na espermatogênese da carpa comum (Cyprinus carpio). Também caracterizamos fenotipicamente as potenciais espermatogônias tronco. Portanto, descrevemos cinco tipos espermatogôniais na carpa comum: espermatogônias indiferenciadas do tipo A (Aund* - Aund), espermatogônias diferenciadas do tipo A (Adiff) e espermatogônias do tipo B (inicial e final). Nesta espécie, o processo espermatogênico durou aproximadamente uma semana. Nossos resultados demonstraram que a população espermatogonial expressa as proteínas c-Kit, Gfrα-1 e POU2. Neste estudo, também foi padronizada a técnica de transplante de espermatogônias na carpa comum. Assim, células germinativas isoladas de kinguios sexualmente maduros foram transplantadas através da papila urogenital de carpas macho quimicamente esterilizadas. As células germinativas derivadas dos doadores foram capazes de colonizar e se desenvolver nos testículos dos receptores. Em geral, nossos resultados reforçam a compreensão da biologia das células germinativas, em especial das potenciais células tronco. Além disso, o transplante, padronizado aqui, é uma abordagem com implicações significativas para a conservação e manejo das espécies valiosas e/ou ameaçadas de extinção. / In vertebrates, spermatogenesis is a highly conserved and organized developmental process, in which a small population of spermatogonial stem cells (SSC) continuosly produce millions of spermatozoa, which are responsible for spreading the male genotype. Likewise other stem cells, SSC are capable of either self-renew or differentiate. Several aspects related to the regulation of SSC activity and physiology are still unknown in teleost fish. Thus, the germ cell transplantation technique becomes a powerful approach to improve the knowledge of SSC biology and spermatogenesis. Briefly, the technique involves the transfer of germ cells isolated from a fertile donor into the testes of a sterile recipient, and transplanted donor germ cells are able to restore the recipient gametogenesis. Taking advantage of this background, we performed morphological and stereological characterization of the different cell types found in the common carp (Cyprinus carpio) spermatogenesis. We also characterized the putative SSC candidates by morphology. Therefore, we described five spermatogonial types in common carp: type A undifferentiated spermatogonia (Aund* - Aund), type A differentiated spermatogonia (Adiff) and type B spermatogonia (early and late). In this species, the spermatogenic process lasted approximately one week. Our findings demonstrated that the spermatogonial population expressed the c-Kit, Gfrα1 and POU2 proteins. Donor germ cells isolated from goldfish were transplanted non-surgically through urogenital papilla into the sexually mature cytoablated common carp recipients. Donor transplanted germ cells were able to colonize and develop in recipients’ testes. Overall, our results strengthens the knowledge of germ cell biology, focusing on stem cells. Finally, transplantation, standardized here, is an approach with significant implications for the conservation and management of endangered and valuable fish species. / CAPES: 15213-12-9
17

Composição, abundância e aspectos reprodutivos das espécies de peixes do reservatório Álvaro de Souza Lima (Bariri, SP) e sua relação com as características ambientais do sistema / Composition, abundance and reproductive aspects of fishes from Álvaro de Souza Lima reservoir (Bariri, SP) and relationships with environmental factors of the system

Fernanda Teixeira e Marciano 05 December 2005 (has links)
A construção dos reservatórios implica em alterações de caráter social, econômico e biológico, que podem interferir de maneira espacial e/ou temporal sobre o ecossistema. Neste contexto, as características das comunidades ícticas têm sido utilizadas para avaliação da degradação ambiental, por serem sensíveis indicadoras de estresses diretos ou indiretos de todo ecossistema. Desta forma, com o intuito de analisar a comunidade íctica do reservatório de Bariri segundo a composição, a diversidade, a dominância das espécies e os aspectos reprodutivos das mesmas, fez-se necessário: 1. Calcular o índice de diversidade (Shannon), a riqueza e a abundância das trinta e sete espécies de peixes coletadas; 2. Aplicar o índice ponderal de dominância; 3. Determinar a estrutura das populações de peixes em relação à composição em tamanho, sexo e proporção sexual; 4. Determinar a relação peso x comprimento e os fatores de condição das espécies; 5. Estabelecer uma escala de maturação e verificar, através da curva de maturação, o período reprodutivo e o tamanho do menor indivíduo em 1ª maturação para cada espécie dominante; 6. Identificar quais as espécies exóticas presentes neste sistema e se a introdução de Plagioscion squamosissimus e Cichla cf. monoculus, em especial, exerciam algum impacto sobre a dinâmica populacional das demais espécies e 7. Verificar quais os fatores ambientais que propiciaram o sucesso reprodutivo das espécies dominantes e de Plagioscion squamosissimus e Cichla cf. monoculus. Assim sendo, concluiu-se que a diversidade ictiofaunística revelou homogeneidade entre as quatro épocas de coleta e que as espécies parecem sofrer influência direta de algumas variáveis limnológicas. Verificou-se ainda, que a ictiofauna é composta por seis espécies dominantes, as quais foram classificadas em três estádios de maturação gonadal, possibilitando verificar que o crescimento era do tipo isométrico para todas as espécies dominantes, sem dimorfismo sexual. Até o presente momento não se pode considerar que, para este reservatório, a introdução das espécies Plagioscion squamosissimus e Cichla cf. monoculus tenham causado efeito aparente sobre as espécies nativas, diminuindo o tamanho da população destas ou ainda alterando a estrutura etária das demais espécies. / The construction of reservoirs cause changes of social, economic and biological alterations, that can interfere spatially and/or temporally upon the ecosystem. In this context, the characteristics of fish communities have been used in order to evaluate environmental degradation, because they are good indicators of direct and indirect stresses in the whole ecosystem. Therefore, aiming to analyze the fish community of Bariri reservoir regarding the species composition, diversity and dominance of species and also their reproductive aspects, it was necessary: 1. Calculate the diversity index (Shannon), the species richness and the abundance of the 37 species collected; 2. Apply the ponderal dominance index; 3. To determine fish population structure regarding size structure, sex and sex ratio; 4. To determine length-weight relationships and their condition factor; 5. Establish a scale of maturation and to verify using the maturation curve, the reproductive period and the minimum individual size in the first reproduction, for each dominant species; 6. Identify which are the exotic species present in the system and to verify if the introduction of Plagioscion squamosissimus and Cichla cf. monoculus, especially had some impact on the population dynamics of other species, and 7. Verify which environmental factors have determined the reproductive success of the dominant species and Plagioscion squamosissimus and Cichla cf. monoculus. It was concluded that fish diversity was homogeneous among the four sampling periods and that the species seem to suffer the direct influence of some limnological variables. It was also verified that the fish community was composed by six dominant species, which were classified in three gonad maturation stages, allowing to verify that growth was isometric for all the dominant species, without sexual dimorphism. Up to now, for this reservoir, it was not possible to consider that the introduction of the species Plagioscion squamosissimus and Cichla cf. monoculus had an apparent effect on the native species of fish, decreasing their population size or changing the age structure of the other species.
18

An Investigation of Pulp Mill Effluents and Their Wood Feedstocks as Potential Neuroendocrine Disruptors of the Fish Reproductive Axis

Waye, Andrew January 2015 (has links)
Common observations of reduced gonad size and spawning inhibition in wild and laboratory raised fish exposed to pulp mill effluents indicate that reproductive neuroendocrine signalling pathways may be upset. This thesis supported the neuroendocrine disruption of reproduction hypothesis by identifying potential disruptors and targets where these impacts may occur. A mechanistic study of the in vivo fathead minnow (FHM) spawning assay used by industry to assess effluent quality showed that ovulation, but not milt production, was impaired. This finding supported the hypothesis that the neuroendocrine cascade that triggers ovulation may be disrupted. I hypothesized that neuroactive constituents previously described in effluents were originating in wood feedstocks and neuroactive extracts of hardwood and conifer feedstocks were identified. Phytochemicals associated with effluents were neuroactive. Structurally similar phenolic phytochemicals showed monoamine oxidase (MAO) inhibition, and resin acid diterpenes displayed glutamic acid decarboxylase (GAD) inhibition. Inhibitors of these enzymes may have impacts on the control of reproduction since MAO metabolizes dopamine, an inhibitor of the neuroendocrine reproductive axis, while GAD synthesizes -aminobutyric acid (GABA), a stimulator of this axis. Bioassay-guided fractionations of effluents and wood feedstocks identified that medium polar extracts of primary- and secondary-treated effluents and balsam fir feedstock contained high GAD inhibitory activity. This activity was associated with chemically complex fractions rather than single active principles. Advanced metabolomic comparison of medium polar extracts of feedstock and treated effluent identified 15 common plant metabolites, demonstrating that phytochemicals entering the mill in wood are surviving pulp production and effluent treatment processes and may be responsible for observed GAD inhibition. Discriminant metabolomics analysis identified 4-acetylpyridine, a novel compound to be described in effluents, as well as two other tentatively identified compounds, as chemical markers of GAD inhibitory effluent fractions. Five tentatively identified chemical markers and (+)-lariciresinol were found in inhibitory balsam fir feedstock fractions. Neuroendocrine pathways that control reproduction in fish, such as dopamine and GABA pathways, are also important drug targets for the treatment of neurological disorders in mammals; therefore these results also have implications for the development of natural health products from phytochemicals and tree extracts common to Canadian forests. By using an interdisciplinary approach (phytochemistry, neuroendocrinology, ecotoxicology), I was able to explore the various implications of my research on the fields of natural health products chemistry and aquatic toxicology.
19

Varianty chromozomu 9 u člověka - od normy k patologii Epidemiologie a význam v klinické genetické praxi. / Variants of human chromosome 9 - from norm to pathology Epidemiology and significance for medical genetics.

Šípek, Antonín January 2019 (has links)
Heterochromatin variants of human chromosome 9 belong to the most common variabilities of human karyotype. The variability involves the large block of constitutive heterochromatin in the pericentric region of chromosome 9, which is composed of various types of repetitive DNA sequences. Those variants can be studied from population epidemiologic, molecular cytogenetic and clinical genetic point of view. We have performed a broad epidemiologic study of the incidence of pericentric inversion of chromosome 9 (inv(9)) and other variants of chromosome 9 in 6 different laboratory cohorts, which included the evaluation of more than 26.000 of cytogenetic reports, the study we published is currently the largest in the world. We expressed the overall incidence of inv(9) to be 1.6% and the total incidence of variants of chromosome 9 to be 3.3-3.9%. Inv(9) was more common in females, however the difference was not statistically significant. Molecular cytogenetic part of the project was based on our own diagnostic approach, which involved the combination of three different commercial FISH probes. Combination of those probes allowed us to differentiate particular subvariants of chromosome 9, which cannot be analyzed only by using G- or C-banding. Using our method, we tested 49 carriers of chromosome 9...
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Táticas reprodutivas e ocorrência parasitária de isópodos em carapeba, Diapterus rhombeus (Cuvier, 1829), no Rio Grande do Norte, Brasil / Reproductive tactics and parasitary occurrence of isopods in carapeba, Diapterus rhombeus (Cuvier, 1829), in Rio Grande do Norte, Brazil

Freitas, Maria Daniana Felix de 18 October 2017 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2018-03-28T21:06:53Z No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:55:19Z (GMT) No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:55:15Z (GMT) No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:57:20Z (GMT) No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) / Made available in DSpace on 2018-06-18T16:57:36Z (GMT). No. of bitstreams: 1 MariaDFF_DISSERT.pdf: 2297623 bytes, checksum: 4700cc8e86349c7cf496397919d441e3 (MD5) Previous issue date: 2017-10-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Diapterus rhombeus is a fish of coastal and estuarine water that can be found throughout the Western Atlantic, from the Gulf of Mexico to Brazil. As it is a peidxe of great abundance it is important to have knowledge about the reproductive and parasitological biology of the species. With this, the objective of this study was to verify the main tactics that compose the reproductive strategy and the condition factor of D. rhombeus and the occurrence of isopod ectoparasites. The study was carried out in marine waters in the Northwest of the Atlantic Ocean (4º 50'57 ''S and 3751'36''W), more precisely in the coast of Areia Branca, RN, Brazil. A total of 298 individuals of the species were captured, in which in the study of their reproductive tactics it was identified that the individuals presented total weight ranges from 51.4g to 220.5g and a total length of 150mm to 245mm, where females were always found to be larger range of total length than males. In the analysis of weight and length both sexes presented a negative allometric growth, that is, the individuals had greater increase in length than in weight. Individuals presented a 1.8M: 1F sex ratio throughout the study. Four stages of gonadal maturation were identified macroscopically: immature, maturing, mature and emptied and microscopic study with histological analysis showed oocyte and sperm development within gonads at each stage of maturation. The length at which individuals entered first maturation was calculated to be 160 mm in total length. The gonadosomatic index (IGS) showed higher peaks for both males and females in November, December and January, indicating that the spawning season occurs soon after this period. The absolute fecundity was 16,313 oocytes and indicated that the females had a synchronous reproductive development in two groups. In the study of condition factor (K) higher peaks were shown shortly after the spawning season, indicating that the greater well-being of the individuals occurs in this period. The parasitic study showed that the species is parasitized by Cymothoa excisa, an isopod parasite that was found inhabiting the oral cavity of the individuals, presenting parasitic indexes with prevalence of 7.38%, mean intensity of 1.18 and average abundance of 0.09. In the present work, D. rhombeus individuals possess reproductive tactics that identify the species as a fish seasonal strategist and that the species can be considered as a new host of the C. excisa isotope ectoparasite / Diapterus rhombeus é um peixe de água costeira e estuarino que pode ser encontrado em todo Oeste do Atlântico, desde o Golfo do México até o Brasil. Como se trata de um peidxe de grande abundancia é importante ter o conhecimento sobre biologia reprodutiva e parasitológica da espécie. Com isso, o objetivo deste estudo foi verificar as principais táticas que compõem a estratégia reprodutiva e o fator de condição de D. rhombeus e a ocorrência de ectoparasitos isópodos. O estudo ocorreu em águas marinhas no Norte do Sudoeste do Oceano Atlântico (4º 50’57’’S e 3751’36’’O), mais precisamente no litoral de Areia Branca, RN, Brasil. Foram capturados 298 indivíduos da espécie, nos quais no estudo das suas táticas reprodutivas foi identificado que os indivíduos apresentaram amplitudes de peso total 51,4g a 220,5g e comprimento total de 150 mm a 245 mm, onde as fêmeas sempre foram encontradas em maior amplitude de comprimento total que os machos. Na análise de peso e comprimento ambos os sexos apresentaram um crescimento alométrico negativo, ou seja, os indivíduos tiveram maior incremento em comprimento que em peso. Os indivíduos apresentaram proporção sexual de 1,8M:1F ao longo do estudo. Quatro estádios de maturação gonadal foram identificados macroscopicamente: imaturos, em maturação, maduros e esvaziados e estudo microscópico com análise histológica mostrou o desenvolvimento ovocitário e espermático dentro das gônadas de cada estágio de maturação. O comprimento em que os indivíduos entraram em primeira maturação foi calculado como sendo em 160mm de comprimento total. O índice gonadossomático (IGS) apresentou picos mais elevados tanto para machos quanto para fêmeas nos meses de novembro, dezembro e janeiro, o que indicou que a época de desova ocorre logo após esse período. A fecundidade absoluta foi de 16.313 ovócitos e indicou que as fêmeas apresentam um desenvolvimento reprodutivo sincrônico em dois grupos. No estudo de fator de condição (K) foi mostrado picos mais elevados logo após a época de desova, indicando que o maior bem-estar dos indivíduos ocorre neste período. O estudo parasitário mostrou que a espécie se encontra parasitada por Cymothoa excisa, parasito isópodo que foi encontrado habitando a cavidade bucal dos indivíduos, apresentando índices parasitários com prevalência de 7,38%, intensidade média de 1,18 e abundancia média de 0,09. Registrando no presente trabalho que os indivíduos da espécie D. rhombeus possuem táticas reprodutivas que identificam a espécie como um peixe estrategista sazonal e que a espécie pode ser considerada como um novo hospedeiro do ectoparasito isópodo C. excisa / 2018-03-28

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