Made available in DSpace on 2015-06-17T19:33:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-10. Added 1 bitstream(s) on 2015-06-18T12:48:19Z : No. of bitstreams: 1 000833453.pdf: 664742 bytes, checksum: 9d6e642484cb6ccc9c8e11cbf6cb9cbb (MD5) / Foi realizado um estudo para verificar o efeito da inoculação in ovo de Bacillus subtilis e sua suplementação na ração durante a fase de criação, sobre as características morfológicas e morfométricas do intestino delgado, desempenho e rendimento de carcaça de frangos de corte. O estudo foi composto por dois experimentos. No primeiro foram utilizados 500 ovos férteis de frango distribuídos em cinco incubadoras horizontais. O delineamento utilizado foi em blocos casualizados, sendo cada incubadora considerada um bloco, com cinco tratamentos (Controle, NaCl, 106 UFC, 107 UFC, 108 UFC), e 100 ovos/tratamento. Aos 18 dias de incubação os ovos foram inoculados com as soluções na câmara de ar e ao eclodirem foram avaliados à quantificação e identificação de Bacillus subtilis na mucosa intestinal, taxa de eclosão de ovos de matrizes pesadas, taxa de eclosão total, mortalidade embrionária, qualidade dos pintinhos, peso ao nascer e pesos do intestino, fígado e saco de vitelo dos pintinhos machos. No segundo experimento foram incubados 2700 ovos férteis em uma incubadora CASP de estágio único. Aos 18 dias de incubação 1350 ovos foram inoculados com 107 UFC Bacillus subtilis e 1350 ovos permaneceram sem inoculação. Ao eclodirem os machos foram alojados no galpão de acordo com os tratamentos. O delineamento utilizado foi em blocos casualizados com esquema fatorial 2x2 (inoculação in ovo de Bacillus subtilis X suplementação de Bacillus subtilis na ração), com seis repetições com 35 aves cada, totalizando 840 aves. Foram analisados a morfometria do intestino delgado, os pesos do fígado, intestino e pâncreas aos um, quatro, oito, 13, 20 e 41 dias de idade, o desempenho aos 21 e 42 dias de idade, o rendimento de carcaça e cortes, e a qualidade da carne aos 42 dias de idade. A inoculação in ovo e a suplementação de Bacillus subtilis na ração promoveram melhores resultados para altura das vilosidades e ... / A study was conducted to verify the effect of in ovo inoculation of Bacillus subtilis and feed supplementation during the creation, on the morphological and morphometric characteristics of the small intestine, performance and carcass yield of broilers. The study consisted of two experiments. In the first 500 fertile chicken eggs over five horizontal incubators were used. The experimental design was randomized blocks, each considered as a block incubator, with five treatments (control, NaCl, CFU 106, CFU 107, CFU 108), and 100 eggs/treatment. At 18 days of incubation the eggs were inoculated with the solutions in the air cell and the hatch were evaluated for quantification and identification of Bacillus subtilis in the intestinal mucosa, hatchability of fertile eggs, total rate of hatching, embryo mortality and chick quality, birth weight and weights of the intestine, liver and yolk sac of male chicks. The concentration 107 provided better results relative to hatchability and chick weight at birth. In the second experiment in 2700 fertile eggs were incubated in an incubator CASP single stage. At 18 days of incubation 1350 eggs were inoculated with 107 CFU Bacillus and 1350 eggs remained without inoculation. When the hatch in the shed males were housed according to the treatment. The design was a randomized block design with a 2x2 factorial design (in ovo inoculation of Bacillus subtilis or not X supplementation of Bacillus subtilis in the creation phase or not), with six replicates of 35 birds each, totaling 840 birds. Were analyzed the morphometry of the small intestine, the weights of the liver, intestine and pancreas at one, four, eight, 13, 20 and 41 days of age, the results at 21 and 42 days of age, performance at 21 and 42 days of age, carcass yield and cuts, and meat quality at 42 days of age. The in ovo inoculation of Bacillus subtilis and feed supplementation promoted best results for depths length of villi and crypts in ...

Made available in DSpace on 2014-11-10T11:09:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-09-03Bitstream added on 2014-11-10T11:58:44Z : No. of bitstreams: 1 000729311.pdf: 1030989 bytes, checksum: eaab2165bdf2127142b441d6bab8557d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As formigas da tribo Attini são conhecidas pelo hábito de cultivar fungos mutualistas (Basidiomycota) em uma variedade de materiais coletados para formar o que é chamado de jardim de fungo. Este hábito teve início há cerca de 50 milhões de anos na América do Sul e deu origem a cinco tipos de agricultura, que diferem no tipo de fungo e material coletado. As attíneas utilizam os jardins de fungos como fonte de nutrientes e enzimas, os quais são produzidos não somente pelo fungo mutualista, mas também por outros microrganismos presentes no ninho. Portanto, para as formigas e fungos terem acesso a nutrientes são necessárias associações com outros microrganismos. Estudos das comunidades microbianas associadas às formigas Attini, na maioria das vezes, estão relacionados aos jardins de fungo e objetivam explorar os mecanismos de degradação da biomassa vegetal. Informações sobre a microbiota associada ao corpo das formigas e sua função ainda são insuficientes. As attíneas dependem dos simbiontes para sua nutrição e proteção contra parasitas. Mas alguns desses microrganismos são ameaças às formigas e outros parecem ser apenas comensais. No presente trabalho, as bactérias associadas às formigas Attini Atta laevigata, Trachymyrmex urichi eMycocepurus goeldii foram identificadas por métodos independentes de cultivo e um cenário no qual a evolução das formigas Attini é moldada pela interação com estes microrganismos foi proposto. Além disso, foi desenvolvido um protocolo de lavagem das formigas para eliminar bactérias externas e ser utilizado para amostrar os microrganismos do interior das formigas. Os resultados mostraram diferenças entre as comunidades bacterianas abrigadas pelas formigas Attini estudadas. A discriminação de bactérias internas e externas ao corpo das formigas foi possível devido à padronização e aplicação do protocolo de lavagem desenvolvido. Foi descoberto que nos intestinos da Attini mais basal M. goeldii predomina uma única espécie de Spiroplasma. No entanto, durante a evolução, esta bactéria foi progressivamente substituída por duas espécies de Rhizobiales no intestino da attínea filogeneticamente intermediária T. urichi, e finalmente uma única espécie de Rhizobiales prevaleceu como a espécie bacteriana única nos intestinos da formiga cortadeira mais derivada A. laevigata. As cortadeiras também carregam em suas cutículas, quantidades consideráveis de Acetobacter. Rhizobiales e Acetobacter pertencem a grupos de bactérias fixadoras de nitrogênio. Assim, é concebível que a especialização em mutualistas fixadores de nitrogênio possa ter desempenhado um papel no aumento do tamanho da população e do tamanho do corpo ao longo da evolução das formigas Attini. O aumento da população pode estar associado com o aumento nas taxas de infecção, mas esta tendência foi aparentemente compensada pela alta complexidade social das cortadeiras e pela manutenção de espécies de Burkholderiales e Actinomycetales, encontradas na sua cutícula. Estas bactérias produtoras de antibióticos podem ter assumido o papel protetor que está atribuído a Pseudonocardiaceae nas demais espécies de Attini. Também foi detectada uma associação com espécies de Wolbachia que parecem ser mutualistas e externas ao corpo das attíneas, provavelmente nas cutículas. Esta associação pode ter iniciado na Attini mais basal, se especializado na intermediária, mas foi perdida na mais derivada. As associações mutualistas parecem ser recentes e ter se originado a partir de uma única aquisição das fixadoras de nitrogênio e múltiplas aquisições de bactérias que produzem antibióticos. / Ants of the Attini tribe are known for the habit of cultivating mutualistic fungi (Basidiomycota) on a variety of harvested materials to form what is called the fungus garden. This habit originated approximately 50 million years ago in South America and gave rise to five agricultural systems, which differ in the type of fungus and collected material. Attine ants utilize the fungus garden as a source of nutrients and enzymes, which are not only produced by the mutualistic fungus, but also by other microbes present in the garden. Therefore, for ants and fungi have access to these nutrients associations with other microorganisms became necessary. Studies of microbial community associated with attine ants are mostly related to the fungus gardens and aim to explore the mechanisms of plant biomass degradation. Information on the microbiota associated with the body of ants and its function are still lacking. Attine ants rely on microbial symbionts for nutrition and protection against parasites. On the other hand, some microbes threatens these ants and others appear to be only commensals. In this work, the bacteria associated with the attine ants Atta laevigata, Trachymyrmex urichi and Mycocepurus goeldii were identified by culture-independent methods and a scenario in which the evolution of attine ants is shaped by the interaction with these microorganisms has been proposed. In the present study a washing protocol was also developed to remove external bacteria, and used to sample microorganisms living inside the ants and possibly other insects. The results showed differences between the bacterial communities harbored by the attine ants studied. Discrimination of internal and external ants’ body bacteria was possible due to the standardization and application of the developed washing protocol. It was observed that the intestines of most basal attine M. goeldii are dominated by a single species of Spiroplasma. However, during the attine ants’ evolution, this bacterium was progressively replaced by two Rhizobiales species in the gut of the phylogenetically intermediate T. urichi, and finally a single species of Rhizobiales prevailed as the unique bacterial species in the gut of the most derived leaf-cutter ant A. laevigata. Leaf-cutters also harbor on their cuticles considerable amounts of Acetobacter sp. Both Rhizobiales and Acetobactersp. species are in the group of nitrogen-fixing bacteria. Thus, it is conceivable that specialization in nitrogen-fixing mutualists may have played a role in increasing population and body size during Attini evolution. A larger population is thought to be associated with increases in infection rates, but this tendency was apparently counterbalanced by high social complexity of leaf-cutters and by the maintenance of Burkholderiales and Actinomycetales species, which we only found in the cuticle of ants. These antibiotic-producing bacteria may have assumed the protective role that is currently attributed to Pseudonocardiaceae in the remaining Attini species. We also detected an association with cuticular Wolbachia mutualists, which may have begun in the more primitive Attini, then specialized in the intermediate ones, and finally being lost in the more derived leaf-cutters. Mutualistic associations appear to be recent and originated from a single acquisition of nitrogen-fixing bacteria and multiple acquisitions of antibiotic producing microbes. / FAPESP: 09/09258-5

The study of the gut microbiota of fish began in the 1930’s and since that time a considerable amount of information has been collated on its composition and diversity. These studies have revealed that the microbial communities of the fish gastrointestinal tract are generally difficult to culture on bacteriological media and mainly consist of bacteria, archaea, viruses, yeasts and protists. The bacteria appear to be the most abundant of these microbial groups and their activity may have major implications for host health, development, immunity and nutrition. Therefore, much of the most recent published research has focused on developing improved methods of identifying the extent of the bacterial diversity within the fish gut and unravelling the potential influence of these microorganisms on the health of farmed fish species. However, whilst such studies have improved our knowledge of the dominant bacterial groups present in the rainbow trout gastrointestinal tract, the limited resolution capacity of many of the methods used has meant that our understanding of their baseline composition in healthy fish remains poorly understood. In this study, the bacterial communities that inhabit the intestine, now commonly referred to as the ‘microbiome’, of farmed Rainbow trout (Oncorhynchus mykiss) were characterized using a culture independent high-throughput molecular sequencing method. The microbiome of the intestinal lumen and mucosa was investigated to ascertain the true extent of the bacterial diversity present in this fish species prior to further experiments. It was found that the diversity of the intestinal microbiome was greater than previous studies had reported with a total of 90 and 159 bacterial genera being identified in both the lumen and mucosal regions respectively. The dominant bacterial phyla identified in both of the regions investigated were Proteobacteria, Firmicutes, Fusobacteria, Bacteroidetes and Actinobacteria. Furthermore, the data collected suggested that the intestinal microbiome may be similar in structure between individual fish, and illustrate the utility of next generation molecular methods in the investigation of the fish gut microbiome. A study was conducted to examine the effect of diet on the composition of the intestinal microbiome of rainbow trout. Two diets, one control and one treatment, were prepared which were identical apart from that the treatment diet contained a microalgal component at 5% of the total formulation. These diets were fed to rainbow trout for a total of 15 weeks. At the end of the trial period a total of 12 fish, three from each of four tanks, were sacrificed from each of the control and treatment groups and their intestinal tissue was sampled in order to compare the composition of the microbiome of both groups. The results revealed that both groups of fish shared similar microbiome compositions, with the Tenericutes being by far the most dominant phylum observed. The structure of the intestinal microbiome was not significantly different between both populations of trout tested. An increased level of bacterial diversity was noted in the treatment fish, however, this was not found to be statistically significant. A limited number of bacterial taxa were discriminatory between diets and were significantly elevated in the treatment group. These taxa were predominantly lactic acid bacteria of the genera Streptococcus, Leuconstoc, Lactobacillus, Lactococcus and Weissella. The results of this study suggested that the minor difference in the diets fed resulted in a correspondingly minor alteration in the intestinal microbiome of the tested rainbow trout. This may indicate that diet composition can modify the composition of the intestinal microbiome of these fish. A further study was conducted to investigate the structure of the intestinal microbiome from groups of fish reared in both freshwater cages and aquarium systems, in order to assess whether or not fish raised in different environments share similar microbiomes. This study also employed a novel computational tool, PICRUSt, to analyse the predicted functional capacity of the microbial communities of individual fish sampled from both environments. The data collected suggested that the structure of the intestinal microbiome was similar regardless of where the fish were raised, with the Tenericutes, Firmicutes, Proteobacteria, Spirochaetae and Bacteroidetes representing the dominant bacterial phyla recorded in the rainbow trout intestine. This suggests that the host may regulate the formation of the intestinal microbiome. A significant difference was however noted in community membership between the fish populations tested, which may point to an environmental influence on the intestinal microbiome. These data suggest that both deterministic host factors and stochastic environmental influences play important roles in shaping the composition of the bacterial communities in the intestine of these fish. The PICRUSt analysis revealed that gene pathways relating to metabolism, transport and cellular processes were enhanced in all of the fish studied, which may signal an involvement of these communities in the digestive processes of rainbow trout. In conclusion, this study used high-throughput sequencing methods in order to improve our understanding of the intestinal microbiome of farmed rainbow trout, and the effect of dietary and environmental factors on its composition. This research has generated scientific information relating to baseline bacterial community compositions in healthy fish, which may be used in future experiments including screening these baselines against the effects of novel aquafeed formulations, environmental perturbations or pathogenic challenges.

A suinocultura brasileira encontra-se atualmente em um nível técnico de destaque no contexto mundial. Entretanto, diversas estratégias são utilizadas para restringir a compra dos produtos brasileiros por países estrangeiros, em especial barreiras sanitárias. Os objetivos desse trabalho foram determinar a microbiota fúngica da pele de suínos sem lesões aparentes e estabelecer os possíveis agentes micóticos de importância nesta espécie. Foram obtidas 261 amostras de animais com 20 a 120 dias de idade, provenientes de 11 granjas do Rio Grande do Sul. As amostras foram obtidas apenas dos animais com ausência de qualquer patologia. Essas foram semeadas em Agar Sabouraud com cloranfenicol. Obteve-se o crescimento de 509 culturas, sendo 305 (59,92%) fungos filamentosos e 204 (40,08%) leveduras. A distribuição do número de diferentes colônias isoladas por amostra demonstra uma predominância de monocultura no grupo 1 (animais de 20 a 60 dias de idade) em relação ao grupo 2 (animais acima de 60 dias de idade). Dentre os fungos filamentosos septados, ocorreu predominância dos hialohifomicetos (43,03%) em relação aos feohifomicetos (10,41%), enquanto que observou-se apenas 6,48% de filamentosos asseptados. O Aspergillus (22,90%) foi o gênero de hialohifomiceto mais isolado, com predominância do A. flavus (5,70%). Dentre os feohifomicetos, o gênero Cladosporium foi o mais prevalente (9,04%). No que concerne os zygomicetos, o gênero mais isolado foi Mucor (4,13%). Em relação às leveduras, o gênero Candida foi o mais isolado (14,73%), sendo a distribuição de freqüência das espécies: C. albicans (13,56%), C. parapsilopsis (0,59%), C. famata (0,20%), C. tropicalis (0,20%) e outras espécies de Candida (0,20%). A reduzida quantidade de diferentes fungos isolados por amostra nos animais do grupo 1, em relação ao grupo 2, pode ter sido influenciada pela menor quantidade de grãos utilizada na fabricação de ração nos animais mais novos, maior freqüência de limpeza e desinfecção das instalações, bem como a não mistura de animais provenientes de diferentes origens. A alta prevalência do gênero Candida observada em suínos, um gênero normalmente comensal do trato gastrintestinal, se torna importante quando esses animais são acometidos por doenças imunossupressoras. Estudos clínicos longitudinais e/ou infecções experimentais talvez possam definir a importância destes agentes em suínos. / Brazilian pig production has reached a technical and techological level that stands out in international pig production. However, several strategies have been used to limit access of Brazilian pig products to international market, including health barriers. The objective of our work was to determine the fungal flora of the healthy pig skin and to determine possible micotic agents important for this animal species. 261 samples from 20-120 day old pigles were obtained from 11 pig farms from the State of Rio Grande do Sul, Brazil. All sampled animals were negative for any skin lesions. The samples were cultured in Sabouraud agar and cloranfenicol. Cultures were obtained from 509 materials, with 305 (59,95%) filamentous fungi and 204 (40,08%) yeasts. The distribution of different fungi isolated each simple shows a high prevalence on group 1 (20-60 days old) in relation to group 2 (more than 60 days old). Among septated filamentous fungi, there was a great preponderance of hialohifomycetes (43,03%) in relation to feohifomycetes (10,41%), while only 6,48% were aseptated filamentous. Aspergillus (22,90%) was the most isolated genus of hialohifomycetes and A. flavus (5,70%) was the more prevalent specie isolated. As to zygomycetes, the most isolated genus was Mucor (4,13%). Regarding yeasts, the genus Candida was the most prevalent (14,73%) and the species distribution was: C. albicans (13,56%), C. parapsilopsis (0,59%), C. famata (0,20%), C. tropicalis (0,20%) and other Candida species (0,20%). The little quantity isolated per sample could have been influenced by quantity of grains used in pig feed in these different stages of production, types of facilities, stress and environmental changes could be important to imbalance the flora, as well as favoring diffusion of mycosis in the herds. The limited number of different fungi isolated from animal flora on group 1 may have been influenced by the smaller use of grains in the feed mill in this stage, a better cleaning and disinfection of premises, as well as avoiding mixing pigs of different source. Clinical longitudinal studies and/ or experimental infections perhaps may help to define the importance of these fungi to that species.

abstract: The transition to college has been identified as a vulnerable period for weight gain and the onset of obesity. Research has shown that the gut microbiota is different in obese compared to lean individuals, but a period of weight gain has never been studied in free-living individuals. The objective of this longitudinal, observational study was to assess the association between changes in the intestinal microbiota and weight-related outcomes in healthy college students living in on-campus dormitories at Arizona State University (n=39). Anthropometric measures and fecal samples were collected at the beginning and end of the school year, and microbial relative abundance for A. muciniphila, F. prausnitzii, R. gnavus, and L. acidophilus was measured through qPCR analyses. In this population, body mass index (BMI) and waist circumference (WC) increased by 0.97 ± 1.28 kg/m2 and 2.64 ± 4.90 cm, respectively. Wilcoxon-Rank tests revealed that R. gnavus fold change was significantly different between groups of weight loss/maintenance and weight gain ≥ 5% body weight (0.14 [-0.21, 0.64], n=24 vs. -0.14 [-0.92, 0.05], n=15, respectively; p=0.028). Correlation analyses suggested a significant negative association between A. muciniphila fold change and both % WC change and % BMI change (r= -0.66; p<0.01 and r= -0.33; p=0.04, respectively). However, multivariate regression analysis controlling for sex and race/ethnicity showed a significant association between A. muciniphila and % WC change, but not % BMI change (R2= 0.53; p<0.01 and R2= 0.24; p=0.15). F. prausnitzii was not associated with weight-related outcomes in this sample. L. acidophilus was excluded from study analyses after subsequent qPCR trials revealed no amplification in participant samples. Overall, this was the first study to show a relationship between A. muciniphila fold change and weight-related outcomes over a period of weight gain. Specifically, A. muciniphila was strongly negatively associated with WC in this sample. Further research is needed to more accurately describe these associations and potential mechanisms associated with the shift in gut microbiota observed with weight gain. Findings from future research may be used to develop interventions for college students aiming to shift the gut microbiota to prevent weight gain. / Dissertation/Thesis / Masters Thesis Nutrition 2017

Orientador: Katia Sivieri / Coorientador: Karina Maria Olbrich dos Santos / Banca: Adriane Elisabete Antunes de Moraes / Banca: Luis Vitor Silva do Sacramento / Resumo: Objetivo: Identificar os principais compostos bioativos presentes em uma bebida fermentada probiótica sabor uva, à base de leite de cabra, adicionada ou não de extrato de bagaço de uva e avaliar seu efeito funcional sobre a microbiota intestinal em Simulador do Ecossistema Microbiano Humano (SEMH). Métodos: Foram realizadas análises de caracterização química (composição centesimal e fibra alimentar, perfil de ácidos graxos, teor de compostos fenólicos totais e atividade antioxidante) e microbiológicas (viabilidade de L. rhamnosus e S. thermophilus) das bebidas. O efeito funcional das bebidas foi avaliado através da composição da microbiota intestinal (enumeração de Lactobacillus spp., Bifidobacterium spp., Anaerobios totais, Clostridium spp. e Coliformes totais), produção de ácidos graxos de cadeia curta e íons amônio, bem como sob a capacidade antioxidante. Resultados: Os resultados obtidos neste estudo demonstraram que as bebidas formuladas, enriquecidas ou não com extrato de bagaço de uva apresentaram alto (p≤0.05) teor de fibras dietéticas, ácido oleico, compostos fenólicos e atividade antioxidante. Ainda, mantiveram (p≤0.05) a viabilidade do L. rhamnosus e S. thermophilus durante a passagem pelo trato gastrointestinal e, exerceram efeitos positivos sobre a microbiota intestinal, uma vez que alteraram (p≤0.05) a composição da comunidade microbiana, aumentaram (p≤0.05) a produção de ácidos graxos de cadeia curta e capacidade antioxidante e diminuíram (p≤0.05) a concentração de íons amônio. Conclusão: Ambas as formulações, adicionada ou não de extrato, exerceram um efeito positivo sobre a microbiota intestinal, uma vez que proporcionaram modificações metabólicas positivas nas diferentes regiões... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Objective: The objective of this study was to identify the main bioactive compounds present in a grape-flavored fermented probiotic drink made of goat milk, with or without added grape pomace extract and evaluate its effects on gut microbiota in the Simulator of Human Intestinal Microbial Ecosystem (SHIME®). Methods: Chemical (centesimal composition and dietary fibre, fatty acid profile, total content of phenolic compounds and antioxidant activity) and microbiological analyses (viability of L. rhamnosus and S. thermophilus) of the drinks were carried out. The functional effect of the drinks was evaluated through the composition of the intestinal microbiota (enumeration of Lactobacillus spp., Bifidobacterium spp., Clostridium spp., anaerobios total and coliforms total), production of short-chain fatty acids and ammonium, as well as under the antioxidant capacity. Results: The results obtained in this study have shown that the drinks, enriched or not with grape pomace extract, showed high (p≤ 0.05) content of dietary fibre, oleic acid, phenolic compounds and antioxidant activity. Still, they kept (p≤0.05) the viability of L. rhamnosus and S. thermophilus during the passage through the gastrointestinal tract and exerted a positive effects on the intestinal microbiota, since changed (p≤ 0.05) the composition of the microbial community, increased (p≤0.05) the production of short chain fatty acids and antioxidant capacity and decreased (p≤0.05) the concentration of ammonium. Conclusion: Both formulations added or not of grape pomace extract, exerted a positive effect on the intestinal microbiota, since it provided positive metabolic changes in different regions... (Complete abstract click electronic access below) / Mestre

Le microbiote intestinal affecte la plupart des processus physiologiques de l’hôte, et plus particulièrement la digestion et le métabolisme. Cependant, les mécanismes moléculaires en jeu restent encore peu connus. Pour répondre à cette question, nous utilisons un modèle gnotobiotique simple : la larve de Drosophile monoassociée à un de ces symbiont naturel : Lactobacillus plantarum. Notre groupe a montré que L. plantarum promeut la croissance larvaire d’individus soumis à une carence en protéines. En effet, les larves monoassociées à L. plantarum se développent bien plus rapidement que des individus axéniques. Ainsi, L. plantarum tempère l’effet délétère de la carence nutritionnelle. Cette amélioration de la croissance repose en partie sur la hausse du niveau d’expression des protéases digestives de l’hôte ainsi que sur la modulation de la voie de signalisation TOR (Target Of Rapamycin) de la Drosophile par les bactéries symbiotiques. Notre travail s’est focalisé sur la recherche d’autres mécanismes génétiques impliqués dans l’interaction entre la Drosophile et L. plantarum au cours de la croissance larvaire. Nos résultats montrent que les variations génomiques naturelles de la Drosophile affectent l’intensité du bénéfice de croissance conféré par L. plantarum. En outre, les bases de notre étude ont permis de mettre en évidence que le microbiote intestinal a la capacité d'agir comme "tampon génétique" en compensant les défauts de croissance causés par le fond génétique des mouches. De plus, L. plantarum permet de diminuer la variation phénotypique de plusieurs caractères de la mouche tels que la croissance, la taille de certains organes et la durée du cycle larvaire. Nous avons également identifié le gène dawdle, codant un ligand de la voie TGF-β, comme acteur de l’interaction Drosophile-L. plantarum. De plus nous avons montré que Dawdle régule les protéases digestives de la Drosophile dans un contexte nutritionnel de carence en protéine, et cette régulation peut-être activatrice ou bien inhibitrice selon l’environnement microbien. / Intestinal microbiota can modulate virtually all aspects of their host physiology, and particularly, digestion and metabolism. However, the molecular mechanisms at play remain largely unknown. To tackle this question, we use a simple gnotobiotic model: Drosophila larvae monoassociated with one of its major natural symbiont, Lactobacillus plantarum. Previous work from our group showed that L. plantarum promotes the juvenile growth of larvae facing a protein scarcity, thereby dampening the deleterious effect of the nutrient deficiency on larval growth. This growth enhancement partially relies on the upregulation of intestinal proteases, as well as on the modulation of the host TOR (Target Of Rapamycin) pathway by the symbionts. My thesis work aimed at unraveling other host genetic mechanisms involved in the interaction between Drosophila and L. plantarum during growth. Our work showed that host natural genomic variations affect the fly physiologic response to L. plantarum. Furthermore, the bases of our work enabled to unveil a novel role of intestinal bacteria, revealing their ability to act as a genetic buffer to compensate the growth impairments due to the fly genetic background. In addition, L. plantarum decreases the phenotypic variations in various host fitness traits (growth, organ size, timing to pupariation) and it also confers robustness to organ patterning. Finally, we showed that the TGF-β ligand, Dawdle plays an important regulatory role on digestive enzymes in a protein-deficient nutritional context, and that this regulation can be inhibitory or activating depending on the microbial environment.

Made available in DSpace on 2014-06-11T19:27:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-15Bitstream added on 2014-06-13T20:36:05Z : No. of bitstreams: 1 marujo_mv_me_jabo.pdf: 288377 bytes, checksum: 375976f0740d39f1692444c9ab347118 (MD5) / Dois experimentos foram conduzidos com o objetivo de avaliar os efeitos da inclusão de celulose purificada, como fonte de fibra insolúvel, na dieta de leitões recém-desmamados. No experimento I, o desempenho, a incidência de diarreia e o tempo de trânsito das dietas no trato gastrintestinal foram avaliados em 72 leitões desmamados aos 21 dias de idade. No experimento II, foram utilizados 32 leitões recém-desmamados para determinar o pH e a viscosidade da digesta no estômago, intestino delgado e ceco; a morfologia e a microbiologia intestinal; os pesos dos órgãos gastrintestinais, do fígado e do pâncreas, e a imunidade animal. Em ambos os experimentos, os tratamentos consistiram de uma dieta basal com adição de 0,0; 1,5; 3,0 ou 4,5% de celulose purificada. O delineamento em blocos completos casualizados foi utilizado em todos os experimentos para controlar variações no peso vivo inicial. Os abates foram realizados aos 35 e 50 dias de idade. O aumento no nível de celulose purificada resultou em efeito quadrático na conversão alimentar, no consumo diário de ração e na incidência de diarreia. Aos 35 dias de idade, o peso relativo do ceco, o pH do intestino delgado, a altura das vilosidades e a relação altura das vilosidades (AV)/profundidade das criptas (PC) do jejuno apresentaram efeito quadrático, enquanto a relação AV/PC do duodeno aumentou linearmente com o aumento do nível de inclusão de celulose purificada. Aos 50 dias de idade, o peso relativo do ceco e do cólon, a contagem de Lactobacillus spp. na porção distal do intestino delgado e a morfologia intestinal do jejuno (AV, PC e relação AV/PC) apresentaram resposta quadrática, enquanto o peso relativo do pâncreas reduziu linearmente com o aumento no nível de celulose purificada. A imunidade dos animais e as viscosidades do conteúdo estomacal... / Two experiments were conducted to evaluate the effects of purified cellulose inclusion in the diets of newly weaned piglets. In trial I, performance, incidence of diarrhea, and gastrointestinal transit time were evaluated from 72 pigs weaned at 21 days of age. In trial II, a total of 32 pigs newly weaned were used to determine pH and viscosity of gastric content, small intestine and cecal digesta, intestinal morphology and microbiology, gastrointestinal organs, liver and pancreas weights, and animal immunity. In both experiments, dietary treatments consisted of a basal diet with 0.0, 1.5, 3.0, or 4.5% of added purified cellulose. The randomized complete block design was used in all experiments to control for variations in initial body weight. The piglets were slaughtered at the age of 35 and 50 days. Increasing purified cellulose level resulted in a quadratic effect on feed conversion ratio, daily feed intake and incidence of diarrhea. At 35 days of age, relative cecum weight, small intestine pH, villous height and villous height (VH):crypt depth (CD) ratio in the jejunum showed a quadratic effect, whereas VH:CD ratio in the duodenum linearly increased with the increasing level of purified cellulose inclusion. At 50 days of age, relative cecum and colon weight, Lactobacillus spp. count in the distal portion of the small intestine, and intestinal morphology in the jejunum (VH, CD, and VH:CD ratio) had a quadratic response, whereas relative pancreas weight was linearly decreased with the increasing purified cellulose level. Animal immunity and viscosities of gastric content and small intestine digesta were not affected by dietary treatments. The inclusion of purified cellulose to the diets reduced the gastrointestinal transit time and levels between 2.3 to 2.8% in the diet of newly weaned piglets provided the best results... (Complete abstract click electronic access below)

Made available in DSpace on 2016-06-02T19:48:16Z (GMT). No. of bitstreams: 1 2825.pdf: 1262073 bytes, checksum: b2962d5f301de96324cede3691966cb9 (MD5) Previous issue date: 2010-01-22 / The control of surgical site infection, especially during clean is important, especially when exposed bone in orthopedic surgery. A study was conducted exploratory study aimed to assess the impact of particulate matter, air and microbial resistance profile of Staphylococcus aureus in suspension for the intraoperative orthopedic procedures in a medium-sized hospital in São Carlos, SP. In the initial ten samples, the results indicate presence of filamentous fungi in 69% of the samples and 93.75% of the bacterial samples were identified as Gram positive and Gram negative 6.25%. In the 10 samples analyzed in the second stage, the UFC's of bacteria had an average of 97.80%, standard deviation of 51.60%, coefficient of variation of 52.75% and range between 21 and 178. We identified the presence of Staphylococcus aureus, Staphylococcus spp. and Shigella spp. 25%, 75% and 25% of samples, respectively. Held an antibiotic for Staphylococcus aureus isolated from the air in the operating room, and found that the strain had high levels of resistance to most antibiotics used, with sensitivity only two of 15 antimicrobial agents tested. The presence of suspended particles was above the recommended standard for the surgery, suggesting the need for an effective control of air quality. It was observed that during surgery there was a significant increase in suspended particles in accordance with WHO standards and CONAMA. The increase in the number of the surgical team in the room probably generated an increase of suspended particles and hence an increase in microbial range. Of the surgeries performed, one can see that in 70% of the operating room door was closed and 50% with air conditioning was off. In 3 (60%) of surgeries in which the air conditioning was off, we found the incidence of a bacterial genus. / O controle da infecção do sítio cirúrgico, principalmente em cirurgias limpas, é relevante, principalmente quando há exposição óssea, em cirurgias ortopédicas. Foi realizado um estudo exploratório e prospectivo que objetivou verificar a incidência de material particulado, microbiota aérea e perfil de resistência de Staphylococcus aureus em suspensão durante o intra-operatório de cirurgias ortopédicas em um hospital de médio porte de São Carlos, SP. Nas dez amostras iniciais, os resultados demonstraram presença de fungos filamentosos em 69% das amostras e 93,75% das amostras bacterianas foram identificadas como Gram positivas e 6,25% Gram negativas. Nas 10 amostras realizadas na segunda etapa, as UFC s de bactérias apresentaram média de 97,80%, desvio padrão de 51,60%, coeficiente de variação de 52,75% e amplitude entre 21 e 178. Foram identificadas a presença de Staphylococcus aureus, Staphylococcus spp. e Shigella spp. em 25%, 75% e 25% das amostras, respectivamente. Realizou-se um antibiograma para Staphylococcus aureus isolados do ar da sala cirúrgica, e verificou-se que a bactéria apresentou elevados índices de resistência a maioria dos antibióticos utilizados, com sensibilidade apenas a dois dos 15 antimicrobianos testados. A presença de material particulado em suspensão estava acima do padrão recomendado durante o intra-operatório, sugerindo a necessidade de um controle efetivo da qualidade do ar. Observou-se que durante os procedimentos cirúrgicos houve um aumento considerável do material particulado em suspensão, de acordo com padrões da OMS e CONAMA. O aumento no número de pessoas da equipe cirúrgica na sala provavelmente gerou um aumento de material particulado em suspensão e, conseqüentemente, um aumento na variedade microbiana. Das cirurgias realizadas, pode-se verificar que em 70% destas, a porta da sala cirúrgica encontrava-se fechada e 50% estava com ar condicionado desligado. Em 3 (60%) das cirurgias em que o ar condicionado estava desligado, observou-se a incidência de um gênero bacteriano.

Made available in DSpace on 2016-07-01T13:10:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-04-06. Added 1 bitstream(s) on 2016-07-01T13:14:07Z : No. of bitstreams: 1 000866061.pdf: 3092347 bytes, checksum: 231b0807cdca7c581bae7f18a5b3c6ac (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dengue é a arbovirose de maior crescimento nos últimos anos, repercutindo em impactos sociais e econômicos devido às altas taxas de morbidade e mortalidade desencadeadas pela infecção. O dengue tem como principal vetor o mosquito Aedes aegypti, distribuído em toda a faixa tropical e subtropical do planeta. Por apresentar hábito hematofágico antropofílico, rápido desenvolvimento e características comportamentais específicas, é um excelente transmissor do vírus dengue. Medidas de controle estão restritas à eliminação do mosquito vetor, uma vez que um tratamento específico ou uma vacina que previna simultaneamente a infecção pelos quatro sorotipos deste arbovírus ainda não estão disponíveis à população. Uma característica que determina a disseminação de doenças é a alta competência vetorial de seus mosquitos transmissores, que tem sido associada à fatores genéticos do mosquito bem como à microbiota intestinal do inseto. O presente estudo avaliou fatores genéticos e microbianos relacionados à competência vetorial de populações naturais de Ae. aegypti com diferenças na susceptibilidades ao vírus dengue sorotipo 4 (DENV-4). Para isso, foi avaliada a susceptibilidade à infecção pelo DENV de duas populações naturais deste inseto (Botucatu-SP e Neópolis-SE) através de ensaios de infecção e quantificação relativa por PCR em tempo real. A expressão gênica diferencial, bem como a diversidade microbiana intestinal, foi realizada através do sequenciamento de nova geração (RNA-seq e sequenciamento do gene 16S rRNA) através das plataformas Illumina HiScan™SQ e MiSeq, respectivamente. Verificamos que as populações estudadas apresentam diferenças na susceptibilidades ao DENV-4 onde Botucatu apresentou maior resistência à infecção quando comparada à Neópolis. Pela análise de expressão gênica diferencial verificamos que houve pouca modulação genica na população de Botucatu em resposta a... / Dengue is the arbovirosis of greater growth in recent years, reflecting on social and economic impacts due to the high morbidity and mortality rates triggered by infection. Dengue has Aedes aegypti as its primary vector, which is distributed throughout tropical and subtropical regions of the planet. Due to its anthropophilic and haematophagic habit, rapid development and specific behavioral characteristics, it is an excellent dengue virus transmitter. Control measurements are restricted to eliminating the mosquito vector since neither specific treatments nor tetravalent vaccines are yet commercially available. One feature that determines the spread of the disease is the high vector competence of its vector mosquitoes, which has been associated to its genetic factors and to its gut microbiota. The present study evaluated genetic and microbial factors related to vector competence of natural populations of Ae. Aegypti with different levels of susceptibilities to dengue virus serotype 4 (DENV-4). For that, we evaluated the susceptibility to DENV-4 infection of two field collected mosquito populations (Botucatu-SP and Neópolis-SE) through infection assays and relative quantification by qPCR. Differential gene expression and gut microbial diversity analyses were performed using next-generation sequencing (RNA-seq and 16S rRNA gene sequencing) through Illumina HiScanSQ and MiSeq platforms, respectively. The populations presented different susceptibility to DENV-4, of which Botucatu showed higher resistance to infection when compared to Neópolis. Differential gene expression analysis revealed that there was little gene modulation in response to DENV infection in Botucatu, while Neópolis showed consistent modulation on several genes related to immune pathways or digestive processes. When comparing to other studies we found that the Toll immune pathway is being activated in this population after infection. However, the comparison of ...