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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.
331

Ecologia e comportamento do ouriço-preto (Chaetomys subspinosus, Olfers 1818) em fragmentos de Mata Atlântica do município de Ilhéus, sul da Bahia / The ecology and behavior of thin-spined porcupine (Chaetomys subspinosus, Olfers 1818) in fragments of the Atlantic forest, Ilheus, southern Bahia

Gastón Andres Fernandez Giné 22 May 2009 (has links)
O ouriço-preto (Chaetomys subspinosus, Olfers 1818), roedor endêmico da Mata Atlântica ameaçado de extinção, foi estudado na região cacaueira do sul da Bahia. O conhecimento acerca de aspectos básicos de sua história natural ainda é insipiente. Neste contexto, foi estudada a ecologia comportamental do ouriço-preto quanto à ecologia alimentar, organização temporal do comportamento, uso do espaço e seleção do habitat, a fim de conhecer suas estratégias adaptativas, seus requerimentos de habitat e embasar ações de conservação. Foram rádio-monitorados quatro indivíduos em vida-livre, por 11 a 13 meses cada, durante 24 dias completos (24h) e 146 noites parciais, totalizando 1.520 horas de observação, entre abril de 2005 a setembro de 2006. Dados sobre o comportamento, localização e uso de recursos foram registrados a cada 10 minutos por visualização direta dos animais. Simultaneamente, foram coletados dados sobre: clima, disponibilidade de alimento, fase da lua, tipo de vegetação na paisagem, estrutura horizontal e vertical da vegetação, abundância de recursos, e composição nutricional de espécies da dieta. Os dados foram analisados através de três abordagens. Os resultados do primeiro enfoque revelam que os ouriços-preto estudados foram estritamente folívoros e especialistas, e não apresentaram mudanças na composição da dieta ao longo do ano. Preferiram folhas jovens, espécies pioneiras, principalmente Fabaceas com capacidade de fixação biológica de nitrogêncio. Os resultados do segundo enfoque indicaram que os ouriços estudados são estritamente noturnos, solitários, possuem baixos níveis de atividade entre outras estratégias voltadas para a conservação de energia. Eles apresentaram ritmo circadiano de atividade e padrão bimodal de atividade que parecem associados a aspectos que permeiam o processo digestivo e de forrageamento. Não mostraram expressivas mudanças comportamentais ao longo do ano, mas em noites chuvosas sua atividade foi reduzida. Os resultados da terceira abordagem indicam que eles possuem áreas de vida pequena, são estritamente arborícolas, e preferem locais com alta complexidade vertical da vegetação e infestação de cipós em todas as escalas de seleção de habitat avaliadas. Dessa forma, as florestas e as áreas de borda foram preferidas pelos ouriçospreto, e raramente foram usadas as capoeiras e sistemas agroflorestais. Este estudo comprova que os ouriços-preto são estritamente folívoros, arborícolas e especialistas. Eles adotam estratégias comportamentais voltadas à conservação de energia, similares a outros mamíferos folívoros, e são altamente seletivos no uso de recursos do habitat. Estes recursos são comuns em áreas florestais sobre perturbação do efeito de borda. Enquanto, por um lado os ouriços-preto mostram ser especializados em bordas de floresta, por outro, evitam áreas forestais estruturalmente simplificadas. A tolerância ao efeito de borda e a evitação dos sistemas agroflorestais pelos ouriços-preto são discutidas no âmbito de sua conservação. / The behavioral ecology of thin-spined porcupine (Chaetomys subspinosus, Olfers 1818), threatened rodent endemic from Atlantic forest, was researched in the cacao-growing region of southern Bahia. The knowledge about basic aspects of specie natural history is still incipient. The aim of the present research was to study feeding ecology, behavior temporal organization, use of space, and habitat selection, to know the adaptation strategies, their habitat requirements and to support conservation actions. In this way, four individuals in situ were followed using radiotelemetry along 11 to 13 months each, during 146 half-nights and 24 complete days (24h), totaling 1520 hours of observation, from April 2005 to September 2006. Data about behavior, localization and use of resources were registered by instantaneous sampling performed each 10 minutes by direct visualization of animals. Simultaneously, data about climatic variables, food availability, moon phase, vegetation types in landscape, horizontal and vertical vegetation structure, resource abundance, and nutritional composition of diets species were collected. Data was analyzed following three different approaches. The results of the first part revealed that the thin-spined porcupines are strictly folivorous and specialist, eating a lot of few species, any change on foraging patterns and diet composition were observed along the year. The preference was for young leaves, pioneer species, mainly Fabaceas with capability of biological nitrogen fixation. The results of the second part indicated that the studied thin-spined porcupines are strictly nocturnal and solitary presenting low level of activity among other strategies for energy conservation. Also, presented circadian rhythm and activity bimodal pattern related to aspects that permeate their foraging and digestive process. They did not change their activities or dislocations due to seasonal but in raining nights their activity was reduced. The results of the third approach revealed that they exhibit small home range, were strictly arboreal and preferred locals with high complexity vertical vegetation and lianas abundance in all the habitat-scales selection evaluated. Thus the forest and the edged areas were preferred by the porcupine, and rarely went to early-growth forest and agro-forest systems. This study confirmed that thin-spined porcupine is strictly folivore, arboreal and specialist. They adopt conservative-energy strategies similar to others arboreal folivorous mammals, and denotes that are highly selective in use habitat resources. Those resources are common in forest areas with edge effect disturbance. While demonstrated to be specialist in edges forest, in other side, they avoid simplified structurally areas. The thin-spined porcupine tolerance to edge effect and their avoidance to agroforest systems are discussed under the focus of conservation.
332

A comunidade e dieta de pequenos mamíferos em uma área de caatinga no Alto Sertão Sergipano

Hirakuri, Valter Levino 26 July 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Considering the habitat influence in the occurrence of animal species and feeding ecology as a key factor on community dynamics, the relationship between habitat components and species richness and the abundance of small mammals community were evaluated, as well as the diet characterization of these species at Caatinga‟s area in Sergipe, Brazil. The capture-mark-recapture (CMR) method was applied at the Grota do Angico Natural Monument (MNGA), 100 Sherman‟s® traps were arranged in four sites (dense hiperxerophytic Caatinga) from July 2012 to February 2013. Monthly, the habitat variables and invertebrates availability were measured. Fecal samples were collected for food items identification. Twenty-four individuals belonging to three species, two marsupials (Gracilinanus agilis, N = 17 and Didelphis al-biventris, N = 1) and one rodent (Wiedomys pyrrhorhinus, N = 6) were captured, the recapture rate was 25%. The richness found was lower than other studies described in this biome. High habitat similarity were observed between the study sites, due to the high amount of litter, and the differences among them were influenced by components such as rock, cactus and brome-liads. The only habitat variable that positively influenced the abundance of G. agilis was the amount of bromeliads, there was no such relationship with W. pyrrhorhinus. Thirty seven fecal samples were collected, nine of W. pyrrhorhinus (all male samples) and 28 of G. agilis (11 female samples and 17 male samples). In these two species intake sample were identified eight invertebrates orders (Hymenoptera, Coleoptera, Hemiptera, Lepidoptera, Blattodea, Or-thoptera, Isoptera e Araneae), pulp and seeds were also registered. This is the first study on the feeding habits of W. pyrrhorhinus and G. agilis in Caatinga‟s biome . The two species showed high rates of arthropods intake and the diet composition of marsupial was similar to others studies in Cerrado biome, although in this study the proportions of consumption were higher. There were two food items new records‟ to G. agilis: Blattodea and Pilosocereus gou-nellei (Cactaceae) seeds. No difference was found between the sexes in the diet of G. agilis, however largest consumer of Hymenoptera by males and Orthoptera by females. Besides this study showed that marsupial has opportunistic feeding habits, consuming the more available arthropods orders in the environment. / Considerando a influência do habitat na ocorrência das espécies e a ecologia alimentar como fatores importantes na dinâmica das comunidades, foi avaliada a relação entre os componen-tes do habitat e a riqueza e abundância de pequenos mamíferos e caracterizada a dieta das espécies em uma área de Caatinga no Alto Sertão Sergipano. O estudo foi realizado no Mo-numento Natural Grota do Angico (MNGA), utilizando-se o método de captura-marcação-recaptura (CMR) por meio de 100 armadilhas tipo Sherman®, dispostas em quatro sítios (caa-tinga hiperxerófila densa) de julho de 2012 a fevereiro de 2013. Adicionalmente, mensurou-se mensalmente as variáveis do habitat e a disponibilidade de invertebrados. Além disso, foram coletadas amostras de material fecal para a identificação dos itens alimentares consumidos. Foram capturados 24 indivíduos pertencentes a três espécies, sendo dois marsupiais (Gracili-nanus agilis, N = 17 e Didelphis albiventris, N = 1) e um roedor (Wiedomys pyrrhorhinus, N = 6); com uma taxa de recaptura de 25%. A riqueza desse estudo foi inferior ao descritos em outros trabalhos no bioma. Os sítios apresentaram alta similaridade em relação ao habitat de-vido a elevada quantidade de serrapilheira e as diferenças entre eles foram influenciadas por componentes como rocha, cacto e bromélia. Dentre as variáveis do habitat, apenas a quanti-dade de bromélias influenciou positivamente a abundância de G. agilis e não houve nenhuma relação destas com W. pyrrhorhinus. Foram coletadas 37 amostras de fezes, sendo nove de W. pyrrhorhinus (todas de indivíduos machos) e 28 de G. agilis (11 amostras de fêmeas e 17 de machos). Foram identificadas oito ordens de invertebrados consumidas pelas duas espécies (Hymenoptera, Coleoptera, Hemiptera, Lepidoptera, Blattodea, Orthoptera, Isoptera e Arane-ae), além do registro de polpa e sementes. Esse é o primeiro estudo sobre o hábito alimentar de W. pyrrhorhinus e G. agilis em área de Caatinga. As duas espécies apresentaram elevadas taxas de consumo de artrópodes e a composição da dieta do marsupial se apresentou similar aos demais estudos realizados em Cerrado; porém nesse estudo as proporções de consumo foram superiores. Dois novos registros de itens alimentares para G. agilis foram obtidos: Blat-todea e sementes de Pilosocereus gounellei (Cactaceae). Não constatou-se diferença na dieta entre os sexos de G. agilis, entretanto houve o maior consumo de Hymenoptera por machos e de Orthoptera pelas fêmeas. Além disso, nesse estudo, esse marsupial apresentou um hábito oportunista, consumindo os representantes das ordens que estavam mais disponíveis no ambiente
333

Plasticidade da inervação cardíaca durante o desenvolvimento pós-natal em préas (Galea spixii, Wagler, 1831) / Plasticity of cardiac innervation during postnatal development in preás (Galea spixii, Wagler, 1831)

Ana Paula Frigo Moura 18 September 2014 (has links)
O gânglio estrelado (GE) é o principal componente da inervação cardíaca extrínseca e está envolvido na gênese de diversas cardiomiopatias. Durante o envelhecimento, o controle neural do coração dos mamíferos é alterado de forma complexa e não clara, geralmente ocasionando decremento da função cardíaca e maior propensão a doenças degenerativas. A ocorrência de resultados dissonantes quanto aos parâmetros morfoquantitativos durante o envelhecimento, como o aumento ou diminuição do número total de neurônios simpáticos, é assunto para discussões interessantes. Esta pesquisa foi conduzida em preás machos (Galea spixii), um pequeno roedor da fauna brasileira. Desta forma, estudou-se o efeito do desenvolvimento pós-natal (maturação e envelhecimento) na macro e microestrutura do gânglio estrelado esquerdo (GEe) de preás, por meio de microscopia quantitativa tridimensional (Estereologia) associada a técnicas de imuno-histoquímica. De acordo com a fase específica do desenvolvimento pós-natal, os animais foram alocados nos seguintes grupos etários: Neonatos, Jovens, Adultos e Senis. Inicialmente, os animais foram submetidos à eutanásia e seus gânglios estrelados esquerdos coletados e fixados em solução de formaldeído (4%) em PBS. Foi realizada amostragem sistemática e uniformemente aleatória (SURS), estimando-se: volume do GEe, volume neuronal e número total de neurônios do GEe. Os principais achados deste estudo foram: i) aumento do comprimento do gânglio - 42% entre Neonato e Senil; 34% entre Jovem e Senil e 35% entre Adulto e Senil; ii) hipertrofia do GEe - 171% entre os grupos Neonato e Adulto; iii) aumento do tecido não neuronal - 268% entre os grupos Neonato e Adulto; iv) estabilidade no número total de neurônios uninucleados, binucleados e total (uni+bi); v) estabilidade no tamanho (volume) dos neurônios uninucleados e binucleados; e vi) estabilidade no número total de neurônios imunorreativos ao Ki-67 (uni+bi). Espera-se que os resultados gerados por esta pesquisa possam esclarecer alguns aspectos estruturais da plasticidade neural durante o desenvolvimento pós-natal de preás, avançando assim o conhecimento acerca da inervação cardíaca extrínseca / The stellate ganglion (SG) is a main component of extrinsic cardiac innervation and is involved in the genesis of various cardiomyopathies. During ageing, the neural control of heart in mammals is altered in the complex shape and unclear, generally cause decrement in the cardiac function and a greater propensity to degenerative diseases. The occurrence of discordant results regarding the morphoquantitative parameters during ageing, such as increase or decrease in the total number of sympathetic neurons, is a subject for interesting discussions. This research was conducted in males preas (Galea spixii), a small rodent of the Brazilian fauna. Therefore, this work aimed to study the effect of postnatal development (maturation and ageing) in the macro and microstructure of the left stellate ganglion (LSG) in preas by dimensional quantitative microscopy (Stereology) associated to immunohistochemistry techniques. According to a specific stage of postnatal development, the animals were allocated into the following age groups: Newborn, Young, Adult and Elderly. The animals were euthanised and the left stellate ganglia were collected and fixed in 4% formaldehyde solution in PBS. A systematic uniformly random sampling (SURS) was performed to estimate: the volume of LSG, neuron volume and the total number of LSG neurons. The main findings of this study were: i) increase in length ganglia - 42% between Newborn and Elderly; 34% between Young and Elderly and 35% between Adult and Elderly; ii) hypertrophy of LSG - 171% between the groups Newborn and Adult; iii) increase of non-neuronal tissue - 268% between the groups Newborn and Adult; iv) stability for the total number of uninucleate neurons, binucleate neurons and total (uni+bi); v) stability in the size (volume) of uninucleate and binucleate neurons; and, vi) stability for the total number of neurons immunorreactive to Ki-67 (uni+bi). It is expected that the results generated for this research may clarify structural aspects of neural plasticity during the postnatal development of preas, thus advancing the knowledge about the extrinsic cardiac innervation
334

Detecção molecular de hantavírus pela técnica de real-time PCR em amostras de roedores silvestres coletadas na região do Vale do Ribeira no Estado de São Paulo. / Molecular detection of hantavirus by Real- time PCR in wild rodents collected on Vale do Ribeira region, São Paulo State.

Jansen de Araujo 18 February 2011 (has links)
O conhecimento sobre hantavirus patogênicos no Brasil até o momento indica que roedores silvestres são os reservatórios naturais. Estes roedores podem eliminar grandes quantidades do vírus através das fezes, urina e saliva (Khaiboullina et al., 2005). A infecção humana pode ocorrer por contato com roedores ou inalação dos aerossóis que contêm o vírus. A síndrome cardiopulmonar por hantavirus (HCPS) tem sido relatada em humanos em muitas regiões do Brasil. Tendo em vista a quantidade de casos de doenças emergentes e re-emergentes nas últimas décadas elegemos algumas regiões para um estudo detalhado sobre a distribuição desses reservatórios virais e consequentemente a caracterização da variante circulante. Com objetivo de adquirir um diagnóstico rápido e sensível, desenvolvemos primers específicos que pela técnica de Real- time RT- PCR é capaz de detectar o genoma viral em apenas uma hora em amostras de pulmões, rins e urina de roedores. Ao todo, nosso trabalho analisou 153 amostras sendo: 126 de roedores silvestres e domésticos, (de cinco diferentes regiões do Estado de São Paulo onde: 10 amostras colhidas no município de Jacupiranga, 61 oriundas de Teodoro Sampaio, 7 de Salesópolis, 48 provenientes de Biritiba Mirim, 16 de Nazaré Paulista) e mais 27 soros de pacientes de diferentes localidades de Minas Gerais. Neste estudo foi possível detectar dez amostras positivas em Biritiba Mirim, quatro em Nazaré Paulista e em vinte e dois soros de pacientes com hantavirose. O monitoramento contínuo através de testes moleculares em animais silvestres é imprescindível para um melhor entendimento da circulação dos hantavirus nessas regiões. Acreditamos que este teste possa auxiliar na vigilância e também no diagnóstico dos hantavirus no Brasil. / Current knowledge of the pathogenic hantavirus indicates that wild rodents are its primary natural reservoir. These rodents can eliminate large amounts of the virus through feces, urine and saliva. Human infection can occur through contact with rodents or inhalation of aerosols containing of the virus. Hantavirus cardiopulmonary syndrome (HCPS) has been reported in humans in many regions of Brazil. In view the number of cases of emerging diseases and re- emerging in recent decades, some regions to were select a detailed study on the distribution of these viral reservoirs, and consequently viral characterization. We developed specific primers to detect the presence of viral genomes using Real- time RT- PCR (Reverse- Transcriptase Polymerase Chain Raction). Altogether, our study analyzed 153 samples: 126 of wild rodents and domestic, of five different regions of São Paulo. 10 samples collected in Jacupiranga municipality, 61 in Teodoro Sampaio, 7 Salesópolis, 48 samples in Biritiba Mirim, 16 of Nazaré Paulista and 27 samples of the serum from patients from different sites of Minas Gerais State. Their samples were tested for hantavirus using the described SYBR Green-based real-time RT-PCR protocol and the specific primers. The presence of hantavirus RNA was detected in 10 rodents from Biritiba Mirim, 4 in Nazaré Paulista and 22 in serum of patients with hantaviruse. The surveillance by molecular tests in wild animals is essential to understood of hantavirus circulation in these regions. This SYBR Green real-time RTPCR method for detection of hantavirus may be useful for surveying hantaviruses in Brazil.
335

Etude des cycles épidémiologiques d'Anaplasma phagocytophilum en France : apport des approches de caractérisation génétique / Study of epidemiological cycles of Anaplasma phagocytophilum in France : contribution of characterization by genetic approaches

Chastagner, Amélie Pierrette 28 October 2014 (has links)
A. phagocytophilum, une bactérie transmise par les tiques, est responsable de l’anaplasmose granulocytaire, une maladie émergente qui infecte une large gamme de mammifères dont l’homme. Actuellement, la description des cycles épidémiologiques de cette bactérie est incomplète. L’objectif de cette thèse est de caractériser la diversité génétique d’A. phagocytophilum chez différentes espèces d’hôtes, afin de déterminer quelles espèces participent au même cycle épidémiologique. D’abord, nous avons caractérisé la diversité génétique d’A. phagocytophilum chez les animaux domestiques malades à l’aide d’une MLSA. Nous avons identifié trois groupes de génotypes infectant les bovins, dont un groupe est partagé avec les chevaux et les chiens, et un avec les chevreuils. Ensuite, nous avons recherché quelles espèces de tiques pouvaient transmettre la bactérie, et quels pouvaient être les réservoirs parmi les mammifères sauvages. En Camargue, un génotype au fort potentiel zoonotique a été identifié chez cinq espèces de tiques du genre Rhipicephalus, Dermacentor et Hyalomma. La prévalence chez des rongeurs suggère qu’ils peuvent être réservoirs, mais la présence de génotypes infectant les bovins chez les mulots est à vérifier. Enfin, la comparaison des génotypes obtenus chez les tiques et les chevreuils par séquençage 454, a montré que la contribution des chevreuils à l’infection des tiques était faible sur le site des Vallons de Gascogne. L’absence de rongeurs infectés sur ce site suggère que d’autres mammifères réservoirs sont présents. Cette étude montre la complexité des cycles d’A. phagocytophilum et l’intérêt des outils moléculaires. / A. phagocytophilum, a tick-borne bacterium, is responsible of the granulocytic anaplasmosis, an emerging disease that infects a large range of mammals including humans. Currently, the description of the epidemiological cycles of this bacterium is incomplete. The objective of this thesis was to characterize the genetic diversity of A. phagocytophilum in different host species to determine those involved in the same epidemiological cycle. First, we characterized the genetic diversity of A. phagocytophilum in sick domestic animals with a MLSA. We identified three groups of genotypes infecting cattle, including one group shared with horses and dogs, and another shared with roe deer. Then, we investigated what species of ticks can transmit the bacteria, and what wild mammals could be reservoirs. In Camargue, a genotype with high zoonotic potential was identified in five species of ticks of the genus Rhipicephalus, Dermacentor and Hyalomma. The prevalence in French rodents suggests that they may be reservoir hosts, but the presence of genotypes infecting cattle in rodents must be checked. Finally, comparing the bacterial genotypes in ticks and roe deer by 454 sequencing, showed that the contribution of the roe deer to tick infection was low in the site of “Vallons de Gascogne”. The absence of infected rodents in this location suggests that other reservoir mammals are present. This study demonstrates the complexity of the A. phagocytophilum cycle and the contribution of molecular tools.
336

Ausência de genotoxidade e redução dos efeitos genotóxicos induzidos por DOX da tintura de sementes de Helianthus annuus Linné (girassol) reveladas pelo ensaio do micronúcleo / Nongenotoxic effects and a reduction of the DOX-induced genotoxic effects of Helianthus annuus Linné (sunflower) seeds revealed by micronucleus assays in mouse bone marrow

Souza, Luiz Silva de 10 July 2012 (has links)
Made available in DSpace on 2016-05-02T13:55:17Z (GMT). No. of bitstreams: 1 Luiz Silva Souza-dissertacao.pdf: 3490471 bytes, checksum: c67d9a32f1552af2738fbcd53645873e (MD5) Previous issue date: 2012-07-10 / In addition to being an important source of nutrients, the potential therapeutic effectiveness of H. annuus L. seeds has been previously demonstrated; the beneficial properties of H. annuus L. seeds include an ability to relieve asthmatic symptoms, protective effects on the stomach, benefits to healing, and anti-inflammatory and anti-microbial properties. This research evaluated the mutagenicity and anti-mutagenicity of oil and tincture of H. annuus L. seeds using the micronucleus assay in bone marrow of mice. The interaction between these preparations and the genotoxic effects of doxorubicin (DOX) was also analyzed. Experimental groups were evaluated after 24-48 h of treatment with N-Nitroso-N-ethylurea (NEU) and DOX (positive controls), NaCl (a negative control), a sunflower tincture (250-2,000 mg.Kg-1 of THALS) and two sources of sunflower oils (250-2,000 mg.Kg-1 of POHALS and FOHALS). Anti-mutagenic assays were carried out using the sunflower tincture and oils separately and in combination with these controls. The frequency of micronucleated polychromatic erythrocytes (MNPCEs) was significantly different (p &#61500; 0.05) between (i) the positive and negative control treatments, (ii) the positive controls and animals treated with THALS and (iii) animals treated with THALS and and THALS combined with the positive controls. However, a slight genotoxicity was observed in the animals treated with the combination of THALS+DOX. Both sources of oils (FOHALS and POHALS) revealed similar results; in these groups, the frequencies of MNPCEs were similar to those observed in negative controls. Statistically significant differences were also observed between the sunflower oil treatments and their associated positive controls. There was no genotoxicity (clastogenicity/aneugenicity) observed in THALS, POHALS and FOHALS regardless of the dose, time (except FOHALS) and gender of mouse (except POHALS and FOHALS). The moderate anti-genotoxic effects of THALS suggest a potential slight protective mechanism against DOX-induced genotoxic effects. / A efetividade terapêutica potencial das sementes de H. annuus L. tem sido demonstrada (alívio dos sintomas da asma, efeitos da proteção gástrica, cicatrização, propriedades anti-inflamatórias e antimicrobianas), em adição à sua importante fonte de nutrientes. Esta pesquisa avaliou a mutagenicidade e anti-mutagenicidade do óleo e da tintura de sementes de H. annuus L. usando o ensaio do micronúcleo em medula óssea de camundongos. A associação sobre os efeitos genotóxicos induzidos pela doxorrubicina (DOX) também foi analisada. Grupos experimentais foram avaliados após 24-48h de tratamento com N-Nitroso-N-ethylurea (NUE) e DOX (controles positivos), NaCl (controle negativo), tintura (250-2.000 mg.Kg-1 de THALS) e duas fontes de óleo de girassol (250-2.000 mg.Kg-1 de POHALS e FOHALS). Ensaios anti-mutagênicos foram realizados usando os controles positives associados com a tintura e óleos de girassol, separadamente. A frequência de eritrócitos policromáticos micronucleados (MNPCEs) foi estatisticamente diferente (p < 0,05) entre (i) os tratamentos controles positives e negativo, (ii) controles positivos e tratamento com THALS e (iii) tratamento com THALS e sua associação aos controles positivos. Contudo, uma leve genotoxicidade foi observada na associação THALS+DOX. Ambas as fontes de óleos (FOHALS e POHALS) revelaram resultados similares, cujas frequências de MNPCEs foram consistentes com aqueles observados no controle negativo. Diferenças significativas também ocorreram entre os tratamentos de óleos e suas associações com os controles positivos. A ausência de genotoxicidade (clastogenia/aneugenia) da THALS, POHALS e FOHALS pode ser inferida independentemente da dose, tempo (exceto para FOHALS) e gênero de camundongo (exceto para POHALS e FOHALS). Efeitos anti-genotóxicos moderados de THALS sugerem um potencial mecanismo ligeiramente protetor sobre os efeitos genotóxicos induzidos pela DOX.
337

Avaliação dos efeitos genotóxicos e antigenotóxicos de Salvia officinalis e seus aspectos terapêuticos em ciência animal / Evaluation of the genotoxic and antigenotoxic effects of Salvia officinalis and its therapeutic aspects in animal science

TERRA, Roberta Soares 31 March 2017 (has links)
Submitted by biblioteca unifenas (biblioteca@unifenas.br) on 2017-09-18T20:18:02Z No. of bitstreams: 1 Roberta Soares Terra Dissertação.pdf: 5586714 bytes, checksum: b90d918d9ac7cb880dcc55847cd8c5fd (MD5) / Made available in DSpace on 2017-09-18T20:18:02Z (GMT). No. of bitstreams: 1 Roberta Soares Terra Dissertação.pdf: 5586714 bytes, checksum: b90d918d9ac7cb880dcc55847cd8c5fd (MD5) Previous issue date: 2017-03-31 / Fundação de Amparo à Pesquisa do Estado de Minas Gerais - FAPEMIG / Salvia officinalis has been widely used in culinary and traditional medicine, and studies have identified numerous chemical compounds and potential therapeutic actions. This study evaluated the genotoxicity of lyophilized hydroalcoholic extract of S. officinalis L. (SO) leaves using the micronucleus assay in mouse bone marrow. The interaction between SO and the genotoxic effects induced by doxorubicin (DXR) was also analyzed – antigenotoxicity assay. Experimental groups consisting of male and female Swiss albinus mice (Unib: SW) were evaluated after 24-48h treatment with cyclophosphamide (CP; 50 mg/kg), DXR (5 mg/kg), NaCl 0.5-2 g/kg) and SO (0.5 g/kg) + DXR (5 mg/kg). The PCEMN analyzes showed differences (p0.05) between SO (1-2 g/kg) and NaCl treatments, regardless of gender and time. DXR induced EPCMNs significantly in both genders and treatment times. Groups of mice treated with DXR showed lower frequencies (p0.05) of PCEMNs when compared to CP control groups (50 mg/kg). Associative treatment (500 mg/kg SO + 5 mg/kg DXR) did not reduce the frequency of DXR-induced PCEMNs (p0.05). The PCE/NCE ratio between control (NaCl, CP and DXR) and experimental genotoxic and antigenotoxic (SO; SO + DXR) treatments were insignificant (p0.05). The results suggest moderately genotoxic effects (clastogeny and/or aneugeny) of S. officinalis L. leaves, dose-dependent (i.e., from 1 g/kg) and gender- and time-independent. However, S. officinalis has no systemic toxicity and antigenotoxic effects (SO + DXR) under the conditions established in the present micronucleus test in mouse bone marrow. / Salvia officinalis tem sido amplamente utilizada na culinária e na medicina tradicional, e estudos têm identificado inúmeros compostos químicos e potenciais ações terapêuticas. Esta pesquisa avaliou a genotoxicidade do extrato hidroalcoólico liofilizado de folhas de S. officinalis L. (SO) usando o ensaio do micronúcleo em medula óssea de camundongos. A interação entre SO e os efeitos genotóxicos induzidos pela doxorrubicina (DXR) também foi analisada – ensaio de antigenotoxicidade. Grupos experimentais constituídos de camundongos machos e fêmeas Swiss albinus (Unib: SW) foram avaliados após 24-48h de tratamento com ciclofosfamida (CP; 50 mg/Kg), DXR (5 mg/Kg), NaCl (150 mM), SO (0,5–2 g/Kg) e SO (0,5 g/Kg) + DXR (5 mg/Kg). As análises de EPCMNs mostraram diferenças (p0,05) entre os tratamentos de SO (1–2 g/Kg) e NaCl, independentemente do gênero e do tempo. DXR induziu EPCMNs significativamente em ambos os gêneros e tempos de tratamento. Grupos de camundongos tratados com DXR mostraram frequências menores (p<0,05) de EPCMNs quando comparados com os grupos controles CP (50 mg/Kg). O tratamento associativo (500 mg/Kg de SO + 5 mg/Kg de DXR) não reduziu a frequência de EPCMNs (p<0,05) induzida por DXR. As proporções de EPC/ENC entre tratamentos controles (NaCl, CP e DXR) e experimentais genotóxicos e antigenotóxicos (SO; SO + DXR) foram insignificantes (p0,05). Os resultados sugerem efeitos moderadamente genotóxicos (clastogenia e/ou aneugenia) de folhas de S. officinalis L., dose-dependente (i.e., a partir de 1 g/Kg) e gênero- e tempo-independentes. Contudo, S. officinalis não apresenta toxicidade sistêmica e efeitos antigenotóxicos (SO + DXR) nas condições estabelecidas no presente teste do micronúcleo em medula óssea de camundongos.
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Genotoxicidade de Handroanthus impetiginosus e lapachol potencialmente aplicáveis na produção animal / Genotoxicity of Handroanthus impetiginosus and lapachol potentially applicable to livestock production

CASTRO, Maysa M. E. 21 February 2018 (has links)
Submitted by biblioteca unifenas (biblioteca@unifenas.br) on 2018-03-02T17:52:47Z No. of bitstreams: 1 Maysa Eduarda de Castro Dissertação.pdf: 1155468 bytes, checksum: c65b96b4486f0cf6c4642c0a68aa6335 (MD5) / Made available in DSpace on 2018-03-02T17:52:47Z (GMT). No. of bitstreams: 1 Maysa Eduarda de Castro Dissertação.pdf: 1155468 bytes, checksum: c65b96b4486f0cf6c4642c0a68aa6335 (MD5) Previous issue date: 2018-02-21 / Fundação de Amparo à Pesquisa do Estado de Minas Gerais - FAPEMIG / Handroanthus impetiginosus (Mart. ex DC.) Mattos (HI) it has been widely used for an extended period in traditional medicine, and several studies have shown the presence of chemical compounds and phytotherapeutic potentials of this plant. The objective was to evaluate the genotoxicity of the extract of H. impetiginosus and lapachol (LAP), one of the main compounds found in this plant, using the mouse bone marrow micronucleus assay. Experimental groups consisting of male and female Swiss albinus mice (Unib: SW) were evaluated after 24-48h (HI) e 24h (LAP) post treatment with Cyclophosphamide (CYCLO, 50 mg.kg-1), NaCl (150 mM), HI (0.5; 1.2 g.kg-1), LAP (0.075, 0.15, 0.30 g.kg-1). For HI, analysis of the MNPCEs showed significant differences between treatment doses (500–2,000 mg.kg-1) and NaCl. PCE/NCE showed significant differences between treatment doses (500–2,000 mg.kg-1) or NaCl compared to CP (50 mg.kg-1). This research suggests presence of genotoxicity in treatment doses 2,000 mg.kg-1, and mild genotoxicity in the others treatment doses (500–1,000 mg.kg-1) of HI, sex and time-independent and absence of toxicity doses-, time- and sex-independent. However, for lapacho, analysis of the MNPCEs showed significant differences between treatment dose (300 mg.kg-1) and NaCl. PCE/NCE showed significant differences between treatment doses (500–2,000 mg.kg-1) or NaCl compared to CP (50 mg.kg-1). This research suggests presence of genotoxicity of LAP, dose-dependent (300 mg.kg-1), but time- and sex-independent and absence of toxicity doses-, time- and sex-independent. / Handroanthus impetiginosus (Mart. ex DC.). Mattos (HI) tem sido muito utilizada por um extenso período na medicina tradicional e vários estudos têm mostrado a presença de compostos químicos e potenciais fitoterapêuticos dessa planta. O objetivo foi avaliar a genotoxicidade do extrato de H. impetiginosus e do lapachol (LAP), um dos principais compostos encontrados nessa planta, usando o ensaio do micronúcleo em medula óssea de camundongos. Grupos experimentais constituídos de camundongos machos e fêmeas Swiss albinus (Unib: SW) foram avaliados após 24-48h (HI) e 24h (LAP) de tratamento com Ciclofosfamida (CICLO; 50 mg.Kg-1), NaCl (150 mM), HI (0,5; 1; 2 g.Kg-1), LAP (0,075; 0,15; 0,30 g.Kg-1). As análises de MNPCEs do grupo tratado com HI mostraram diferenças (p  0,05) entre todas as doses de tratamento (500–2.000 mg.Kg-1) e controle negativo (NaCl). As proporções PCE/NCEapresentaram diferenças significativas (p  0,05) entre as doses de HI (500–2.000 mg.Kg-1) ou controle negativo (NaCl), frente ao controle positivo ciclofosfamida (50 mg.Kg-1).Os resultados sugeremum efeito potencialmente genóxico dependente da dose (2.000 mg.Kg-1) e levemente genotóxico nas demais doses (500–1.000 mg.Kg-1) do extrato de HI, independentemente do tempo de tratamento (24 e 48 h) e do sexo (macho e fêmea), e ausência de toxicidade sistêmica do HI dose, sexo e tempo-independente. Contudo, as análises de MNPCEs do grupo tratado com LAP apresentaram diferenças significativas (p  0,05) entre a dose de tratamento (300 mg.Kg-1) e controle negativo (NaCl), jáas proporções PCE/NCEapresentaram diferenças significativas (p  0,05) entre as doses de LAP (75–300 mg.Kg-1) ou controle negativo (NaCl), frente ao controle positivo ciclofosfamida (50 mg.Kg-1), sugerindopresença de genotoxicidade do LAP, dependentemente da dose de administração fitoterapêutica (300 mg.Kg-1), mas independente do tempo de tratamento (24 e 48 h), e sexo (macho e fêmea), e ausência de toxicidade sistêmica do LAP nas condições do ensaio MN, dose, sexo e tempo-independente.
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Physiological and microbiological studies of nectar xylose metabolism in the Namaqua rock mouse, Aethomys namaquensis (A. Smith, 1834)

Johnson, Shelley Anne 24 August 2006 (has links)
Xylose is an unusual nectar sugar found in the nectar of Protea and Faurea (Proteaceae). Since nectar composition is an important floral characteristic in plant strategies for ensuring reproductive success, the unexplained presence of xylose in Protea nectar prompted this study of the interaction between pollinators and Protea species. Among pollinators that visit Proteaflowers in the south-western Cape Floral Kingdom, South Africa, insects and birds show an aversion to, and are poor assimilators of, xylose, whereas rodents such as Namaqua rock mice Aethomys namaquensis are the only pollinators so far shown to consume xylose willingly, and are able to obtain metabolic energy from this sugar. Mammalian tissues are not capable of catabolizing xylose efficiently, but certain gastrointestinal microflora are, through a process of fermentation which produces short-chain fatty acids used by host animals in oxidative metabolism. I explored mechanisms enabling Aethomys namaquensis to utilize xylose, in particular, the role of resident intestinal microflora in this process. Chapter One discusses pollination syndromes and the definitions thereof, mammal pollination, with particular reference to Australia and South Africa, and explains the rationale behind the questions addressed in this thesis. To assess xylose utilization in wild-caught mice with and without their natural gastrointestinal microflora, an antibiotic treatment was developed (Chapter Two). The veterinary antimicrobial agent, Baytril 10% oral solution, was found to be effective in significantly reducing gut microflora in animals on a four-day treatment protocol. The protocol developed here reduced the gut microflora sufficiently for subsequent experiments comparing xylose utilization in mice with and without intact microflora. Xylose utilization was assessed using 14C-labelled xylose (Chapter Three). Rock mice were caught during Protea humifloraflowering and non-flowering seasons, and fed 14C-labelled xylose. Exhaled CO 2 and excreted urine and faeces were collected, and label recovery determined. These experiments showed that xylose-utilizing bacteria in the rock mouse gut are very important for xylose utilization. More efficient xylose utilization during the flowering season suggests that this component of the gut microflora is inducible. Culturable gut microflora were then isolated from rock mouse faecal and caecal samples, assessed for xylose utilization to identify positive xylose-fermenters and classified by 16S rRNA based taxonomy (Chapter Four). Faecal isolates were Lactobacillus murinus and Enterococcus faecium, and caecal isolates were three Bacillus species, Shigella boydii, one Arthrobacter species and two fungal isolates from Aspergillus and Penicillium genera. The types and concentrations of short-chain fatty acids arising from xylose fermentation by caecal microflora were measured using gas chromatography. The fatty acid profile produced by rock mouse gut microflora is similar to that for other animals that rely on gut microbial fermentation to produce fatty acids then used in oxidative metabolism. Chapter Five concludes with a discussion of possible explanations for the presence of xylose as a nectar sugar, its ecological significance, and the relevance of the fermentative capacity of pollinator digestive systems for xylose utilization in animals. / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted
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Biodiversity of terrestrial small mammals along an altitudinal transect in the Western Soutpansberg, Limpopo Province, South Africa

Munyai, Aubrey 26 February 2015 (has links)
Department of Ecology and Water Resources / MENVM

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