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The communities of microorganisms associated with humans and other animals are characterized by a large degree of diversity and unexplained variation across individual hosts. While efforts to explain this variation in host-associated systems have focused heavily on the effects of host selection, community assembly theory emphasizes the role of dispersal and stochastic demographic processes, otherwise known as ecological drift. In this dissertation, I characterize the communities of microorganisms associated with the zebrafish, Danio rerio, intestine, and assess the importance of microbial dispersal and drift to their assembly. First, I describe changes in the composition and diversity of the zebrafish intestinal microbiome over zebrafish development and show that while host development is a major driver of community composition over time, there remains a large amount of unexplained variation among similar hosts of the same age. I go on to show that random dispersal and ecological drift alone in the absence of host selection are sufficient to explain a substantial amount of this variation, but the ability of these processes to predict the distribution of microorganisms across hosts decreases over host development. Finally, I present an experimental test of dispersal in host-associated systems, and show that not only does dispersal among individual zebrafish hosts have a large impact on the composition and diversity of associated microbial communities, but it can also overwhelm the effects of important host factors, such as the innate immune system. As a whole, this work demonstrates that the composition and diversity of microbial communities associated with animal hosts are not solely the result of selection by the host environment, but rather dispersal and stochastic processes have important and often overwhelming effects on their assembly. To fully understand the assembly of host-microbe systems, we must broaden our focus to include scales beyond that of an individual host and their associated microorganisms. / 10000-01-01

Objetivo: Avaliar o efeito de uma bebida à base de farinha de banana verde (FBV) com cacau na microbiota intestinal, níveis de citocinas e capacidade antioxidante total em mulheres com sobrepeso e adiposidade abdominal. Metodologia: Ensaio clínico prospectivo randomizado duplo-cego, realizado no período de julho de 2014 a novembro de 2014. O estudo foi conduzido com voluntárias cadastradas no Projeto Nutrir Vidas, com idades entre 20 a 50 anos de idade. Foram distribuídas randomicamente em dois grupos de 30 voluntárias cada. O grupo teste recebeu uma bebida funcional com adição de FBV e o grupo controle recebeu uma bebida funcional com os mesmos ingredientes, porém sem adição de FBV. Para analisar o efeito da bebida na microbiota intestinal, foram avaliadas a consistência, forma, cor e determinação dos ácidos graxos de cadeia curta (AGCC) nas fezes das voluntárias. E ainda aplicado um questionário baseado no Gastrointestinal Sympton Rating Scale (GSRS). A determinação dos AGCC foi feita por meio da Cromatografia Líquida de Alta eficiência (HPLC). A quantificação das citocinas foi realizada por meio do Kit cytometric beads array (CBA). E para avaliar a capacidade antioxidante total (CAT) foi utilizado um kit enzimático. Os dados obtidos no estudo foram analisados utilizando o software SPSS versão 19. Para a consistência e cor das fezes foi utilizado o Teste exato de Fisher. Aplicado o Teste-T pareado para análises dos AGCC e CAT. Para o Questionário GSRS e citocinas utilizou-se o Teste de Wilcoxon para as variáveis não-paramétricas e Teste Mann-Whitney para comparar o efeito entre os tratamentos. O nível de significância adotado foi de p<0,05. Resultados: A bebida à base de FBV apresentou em sua composição alto teor de fibras, amido resistente e compostos fenólicos. Não apresentou efeito significativo na consistência e cor das fezes. No entanto, promoveu aumento do ácido propiônico e redução dos sintomas gastrointestinais. Exerceu também efeito no sistema imunológico com o aumento da interleucina-2 (IL-2) após a intervenção do estudo. Nenhum efeito na CAT foi observado com o consumo do produto desenvolvido. Conclusão: A bebida funcional à base de FBV exerce efeito considerável sobre a microbiota intestinal e na IL-2. Entretanto não foi observado nenhum efeito na CAT. / Objective: To evaluate the effect of a drink unripe banana flour base (UBF) with cocoa in intestinal microbiota, cytokine levels and total antioxidant capacity in women with overweight and abdominal obesity. Methodology: a randomized prospective double-blind clinical trial, conducted from July 2014 to November 2014. The study was conducted with registered volunteers in Nourishing Lives Project, aged 20 to 50 years old. They were randomly divided into two groups of 30 volunteers each. The test group received a milk drink with added UBF and the control group received a milk beverage with the same ingredients, but without addition of UBF. To analyze the effect of drink on intestinal microbiota were evaluated consistency, color, shape and determination of short chain fatty acids (SCFA) in the feces of volunteers. And yet a questionnaire based on Gastrointestinal Sympton Rating Scale (GSRS). The determination of SCFA was made by high-performance liquid chromatography (HPLC). The quantification of cytokines was performed using the cytometric bead array kit (CBA). And for assessing total antioxidant capacity (TAC) an enzymatic kit was used. Data from the study were analyzed using the SPSS software version 19. For consistency and color of faeces was used Fisher's exact test. Applied the T-Test paired for analysis of SCFA and CAT. For GSRS Questionnaire and cytokines used the Wilcoxon test for variables and nonparametric Mann-Whitney test to compare the effect between treatments. The significance level was set at p <0.05. Results: The drink to UBF presented in a high-fiber composition, resistant starch and phenolic compounds. No significant effect on the color and consistency of faeces. However, it promoted increase of propionic acid and reducing gastrointestinal symptoms. Also has influence on the immune system with increased interleukin-2 (IL-2) after the intervention study. No effect on TAC was observed with the consumption of the product developed. Conclusion: The functional beverage to UBF base exerts considerable effect on the intestinal microbiota and IL-2. However there was no observable effect on TAC. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

Made available in DSpace on 2018-08-01T23:26:21Z (GMT). No. of bitstreams: 1 tese_9469_VIVIAN BERNHARD Dissertação DEFESA 18.12.2015 (3).pdf: 1793766 bytes, checksum: 60f2a751f603dea9b1e764578db08eee (MD5) Previous issue date: 2015-12-18 / O entendimento da cavidade oral como uma fonte de infecção focal à distância tem sido discutido há décadas. Neste contexto, muitos estudos consideram a doença periodontal como um fator de risco em potencial associada às doenças sistêmicas, tais como, parto prematuro e baixo peso ao nascimento, doença pulmonar, diabetes, aterosclerose e problemas cardiovasculares. Além disso, uma relação entre doença periodontal e câncer mostra que indivíduos jovens com lesões periodontais e com perda dos dentes molares possuem maior risco para morte prematura de doenças fatais, tais como, neoplasias malignas e doenças cardiovasculares. Por sua vez, outros estudos sugerem associação da periodontite com câncer de mama, próstata, pâncreas, pulmão, câncer do trato digestivo como um todo, câncer coloretal, bexiga, próstata e colo uterino. OBJETIVO: Avaliar a condição clínica periodontal e microbiológica do biofilme subgengival em mulheres com câncer de mama assistidas no Hospital Universitário Cassiano Antônio de Morais (HUCAM) no Espírito Santo. METODOLOGIA: Estudo transversal com participação de 44 mulheres voluntárias com câncer de mama portadoras de doença periodontal. Parâmetros clínicos periodontais e 144 amostras de biofilme subgengival foram submetidas à extração do DNA por meio da técnica de hibridização Checkerboard DNA-DNA. A análise estatística caracterizou-se por meio da frequência observada, porcentagem, média, mediana e desvio padrão, além de estatísticas de testes adotando-se o nível de significância de 5%. RESULTADOS: Bolsas periodontais de 4,0mm a 5,0mm apresentaram frequência de 59%; o nível clínico de inserção para bolsas &#8805;6,0mm alcançou 71,8%; o sangramento à sondagem atingiu média de 27,6%; e a média de índice de placa visível foi de 45,7%. A bactéria Tannerella forsythia (62,7%) mostrou significância para bolsas moderada (p<0,01) e nível clínico de inserção (p=0,440), enquanto a bactéria Parvimonas micra (62,8%) apresentou significância para bolsas profundas (p<0,01) e nível clínico de inserção (p<0,001). As bactérias do complexo amarelo, Streptococcus oralis, S. intermedius e S. gordonii apresentaram significância para bolsas profundas e nível clínico de inserção &#8805;6,0mm. CONCLUSÃO: Alguns estudos mostram a relação entre a carga bacteriana e o desenvolvimento e progressão do câncer, sendo justificável o controle do biofilme oral a fim de reduzir a 8 carga microbiana da boca para combater o desenvolvimento carcinogênico. Apesar do papel das bactérias periodontopatogênicas na etiopatogênese da lesão de câncer de mama ainda não estar esclarecida na literatura, mais estudos clínicos randomizados controlados são necessários para determinar se existe qualquer elemento causal na associação da doença periodontal e câncer de mama.

Made available in DSpace on 2018-08-01T23:26:23Z (GMT). No. of bitstreams: 1 tese_9766_Dissertação Maria da Conceição.pdf: 21249310 bytes, checksum: f16643971850a036f3906608c6097b72 (MD5) Previous issue date: 2016-03-31 / As infecções dentárias e a doença periodontal podem agir como fatores de risco para o câncer de mama. Porém, pouco se sabe da composição da microbiota periodontal nos indivíduos com câncer de mama e sua relação com a perda dentária e a infecção periodontal. OBJETIVO: Avaliar a condição clínica e microbiológica do biofilme subgengival em mulheres com e sem câncer de mama. METODOLOGIA: Estudo caso-controle e amostra (n=92) constituída por 62 mulheres com câncer de mama e 30 mulheres sem câncer de mama portadoras de doença periodontal. 92 amostras de biofilme subgengival oriundas do sítio periodontal mais profundo foram avaliados microbiologicamente. O nível de significância adotado foi de 5% e o teste de Mann-Whitney (1947) foi requerido para verificar as diferenças entre as médias dos grupos caso e controle. Para avaliar as correlações entre os complexos de bactérias nos grupos, se utilizou a correlação de Spearman. RESULTADOS: Com relação à perda dentária encontrada nos maxilares superiores e inferiores, houve significância entre os grupos (p=0,002/Caso; p=0,012/Controle), da mesma forma que o sangramento à sondagem, porém com significância para o grupo controle (p=0,003). Com relação à detecção das espécies bacterianas, Treponema denticola foi a espécie prevalente (90,0%) do complexo vermelho nas amostras no grupo caso, seguido por Porphyromonas gingivalis (80%), e, Tannerella forsythia (70,0%). Já no complexo laranja, as espécies Fusobacterium nucleatum (sp. polymorphum), Fusobacterium nucleatum (sp.nucleatum) e Prevotella nigrescens foram as mais prevalentes (98,3%; 91,7% e 90,0%), enquanto que no complexo amarelo, Streptococcus gordonii e Streptococcus oralis foram as mais prevalentes (95,0%; 95,0%). P. gingivalis mostrou uma relação positiva com a perda dentária nos dentes superiores e inferiores no grupo com câncer de mama (p=0,017; p=0,038), o mesmo ocorrendo para T. denticola (p=0,003; p=0,008). O sangramento à sondagem apresentou uma relação positiva e estatisticamente significante (p=0,014) para os dentes superiores no grupo controle. Outras espécies bacterianas mostraram associações estatisticamente significantes no grupo caso: P. nigrescens (p=0,028), F. nucleatum (sp. polymorphum) (p=0,002), Campylobacter showae (p<0,001), F.periodonticum, Streptococcus intermedius (p=0,013) e S. gordonii (p<0,001). O perfil bacteriológico predominante para bactérias (contagem média das cópias de DNA) nas mulheres do grupo controle destacou seis microrganismos e com significância estatística: T. denticola, Parvimonas micras, F. nucleatum (sp.polimorphum), F. nucleatum (sp.nucleatum) e S. oralis. CONCLUSÃO: As mulheres com câncer de mama mostram uma associação significante com a perda dentária na presença das espécies P. gingivalis e T. denticola. Além disso, o grupo caso tem 2,1 vezes mais chances de ter perda no molar inferior quando não há detecção da espécie S. intermedius em comparação ao grupo controle. Já a perda no molar superior quando há detecção desta bactéria aumentam estas chances em 1,2 vezes. As mulheres sem câncer de mama apresentaram associação significante entre a espécie T. denticola e o sangramento gengival à sondagem.

Objectives: The aim of this pilot study was to compare the changes in oral and gut microbiota, endotoxemia, and systemic and local inflammatory markers following oral interventions in subjects with and without cirrhosis. Methods: Study subjects displaying gingivitis or mild/moderate periodontitis were placed into two groups: with cirrhosis (n= 24) and without cirrhosis (n=21). Each subject received nonsurgical periodontal therapy. Serum, stool and saliva samples were collected prior to and 30 days post-therapy and analyzed for stool/saliva microbiome, MELD score, endotoxin and IL-6 levels. Results: There was no difference in age, gender and the periodontal disease status between groups. At day 30 post therapy, there was a significant reduction in MELD score, endotoxin levels, IL-6 levels and oral and stool microbiome dysbiosis in cirrhotic patients. Conclusion: Endotoxemia and systemic inflammation can be reduced following periodontal therapy, which is likely due to improvement in oral-origin microbiota in both saliva and stool in cirrhotic patients.

The effect of genetically modified crop plants on the microbiology of the rhizosphere was investigated using the single-gene Bt cotton as a case study. The project compared the rhizosphere microbiota of four Ingard® 1cotton plant varieties that were closely matched with their non-GM parental strains. The plants were grown in three different Australian soils, ie, a vertisol from a cotton-growing region, and two soils, a fine sandy loam and a red sand from South Australia that had not been exposed to cotton. At the time of the commencement of the project, the only commercially available genetically modified plants were cotton and carnations. The cotton industry in Australia is worth $1.5b annually, and care of the soil and the dynamics of its living microbial consortia needs to be understood for optimum management to enable agricultural sustainability. The general outline of the thesis incorporated four main sections: 1. Experimental setup and analysis of the soils and plants to be used, quantification of the Cry1A(c) plant-produced Bt protein, and its persistence in the soil environment. 2. Measurement of the selected microbial populations of bacteria, fungi, AMfungi, protozoans and nematodes, by counting and estimation by dilution and most-probable number methods. 3. Assessment of selected metabolic pathways to determine the effects on the soil microbial community by chemical and other biochemical methods 4. An overall analysis between different group ratios of expression of each of the variables tested, and the summary of the risk analysis and conclusion. The outcome of this work was the acquisition of scientific data to produce an environmental impact report. The findings of this study showed that generally the microbial populations and the products of major metabolic pathways correlated more closely within the non-GM and GM plant rhizospheres of the paired trials than those of separate trials, indicating that soil and plant cultivar had a stronger environmental effect. The results obtained from the paired trials did not show that there were consistent effects on the rhizosphere soil microbiota that could be attributed to the presence of the Cry1A(c) Bt plant protein on the selected strains of cotton plants. The results from the tests of the paired trials correlate highly with previously published work that the risk factors of genetically modified cotton plants on the microbiology of the rhizosphere soil were found be negligible and not consistent across trials. 1 ® Monsanto Co. St Louis, MO.

Non-alcoholic fatty liver disease (NAFLD) includes simple hepatic steatosis (SS) and non-alcoholic steatohepatitis (NASH). NAFLD is tightly linked to obesity and is thought to be secondary to various noxious signals, some of which may originate from the intestinal microbiota (IM). Despite a growing body of evidence supporting a link between obesity and altered IM, there are no studies assessing the IM of patients with NAFLD. In this cross-sectional study we aimed at comparing fecal levels of total bacteria, Bacteroidetes, C. coccoides, C. leptum, Bifidobacteria, E. coli, and Archaea between healthy controls (HC) and patients with SS or NASH. We found higher C. coccoides levels in NASH compared to SS and lower percentage Bacteroidetes in NASH compared to SS and HC. Controlling for body mass index and fat intake we found an association between presence of NASH and percentage Bacteroidetes. The latter inversely correlated with insulin resistance.

Two experiments were conducted to evaluate the effect of fructooligosaccharide (FOS) supplementation in broiler chickens. In experiment 1, the effect of FOS supplementation and in combination with phytase on growth performance, bone quality and phosphorus utilization was evaluated in broiler chickens fed standard or low calcium (Ca) and phosphorus (P) diets. The phytase supplementation in low Ca and P diets improved growth performance, bone quality and P utilization. The combination of phytase and FOS increased BW gain and P retention. However, supplemental FOS alone had negative effects on bone quality. Experiment 2 investigated the effect of FOS supplementation on growth performance, immune responses, intestinal morphology and ileal microbiota with or without Salmonella Enteritidis lipopolysaccharide (LPS) challenge. Supplemental FOS improved ileal mucosa thickness, modified ileal microbiota, elevated cytokine gene expressions, altered leukocytes composition and increased serum antibody levels in response to LPS challenge. Fructooligosaccharide supplementation may play a protective role on gut development and immunity of broiler chicken.

Non-alcoholic fatty liver disease (NAFLD) includes simple hepatic steatosis (SS) and non-alcoholic steatohepatitis (NASH). NAFLD is tightly linked to obesity and is thought to be secondary to various noxious signals, some of which may originate from the intestinal microbiota (IM). Despite a growing body of evidence supporting a link between obesity and altered IM, there are no studies assessing the IM of patients with NAFLD. In this cross-sectional study we aimed at comparing fecal levels of total bacteria, Bacteroidetes, C. coccoides, C. leptum, Bifidobacteria, E. coli, and Archaea between healthy controls (HC) and patients with SS or NASH. We found higher C. coccoides levels in NASH compared to SS and lower percentage Bacteroidetes in NASH compared to SS and HC. Controlling for body mass index and fat intake we found an association between presence of NASH and percentage Bacteroidetes. The latter inversely correlated with insulin resistance.