Bacterial community of pond's water, sediment and in the guts of tilapia ( Oreochromis niloticus ) juveniles characterized by fluorescent in situ hybridization technique

Information about bacterial community structure and functioning in fish farming ponds remains scarce, mainly due to methodological difficulties in counting and identifying uncultured bacteria. The main objective of this study was to evaluate the degree of similarity between the bacterial community of the digestive tract of tilapia (Oreochromis niloticus) juveniles and that of the test pond’s water and sediment, using the Fluorescent In Situ Hybridization (FISH) technique. Samples of water, sediment and gut content of 30 tilapia juveniles from a single nursery ground were collected in January 2010. Potentially probiotic and pathogenic bacteria of the species Bacillus, Lactobacillus brevis, Lactobacillus collinoides, Lactobacillus coryniformis, Lactobacillus farciminis, Vibrio and Pseudomonas fluorescens were found in different samples using specific fluorescent probes. The similarity between bacterial community environments and gastrointestinal tracts was determined using the Morisita-Horn index. The fish guts presented higher abundances of Pseudomonas fluorescens, Bacillus, Lactobacillus brevis and Lactobacillus collinoides. The bacterial community composition of tilapia gastrointestinal tract was more similar to the water than the sediment of the pond. The results of this study showed that the FISH technique can be easily used for monitoring of probiotics and pathogen detection in aquaculture systems

Microbiota bucal versus mucosite oral durante o tratamento para o câncer: uma revisão

Introduction: Oral microbiota has been implicated on oral mucositis (OM) that occurs during cancer therapy, however without consensus. Objective: This study, aimed to establish, through a review, the association between oral microbiota and OM at head and neck cancer therapy (HNCT). Material and methods: The search of PubMed was performed considering 2008-2018 period, and the descriptors “oral mucositis” and “oral microbiota” in subheadings etiology and microbiology into the Medical Subject Heading (MeSH) “Head and Neck Neoplasms”. The conducting question was “Is there an oral dysbiosis during HNCT associated with OM?”. Results: 22 articles were selected under two steps of data extraction: articles that evaluated de oral microbiota during HNCT (n=13), and articles that also focused in OM (n=9). Conclusion: The evidence presented in the literature suggests associations of oral microbiota dysbiosis with the progression and worsening of radiation-induced OM. However, to define a microbial core for the disease, future standardized studies are required.Introdução: A microbiota bucal tem sido associada à mucosite oral que ocorre durante a terapia para o câncer apesar de não haver consenso.  Objectivo: Este estudo objetivou estabelecer por meio de uma revisão da literatura a associação entre a microbiota bucal e a mucosite oral durante a Terapia para o Câncer de Cabeça e Pescoço (TCCP). Material e métodos: Foi realizada uma busca na base de dados PubMed no período de 2008-2018 utilizando-se as palavras chave “oral mucositis” e “oral microbiota” nos subtítulos “etiology” e “microbiology” do descritor “Head and Neck Neoplasms” da base Medical Subject Heading (MeSH). A questão norteadora do estudo foi: “Ocorre uma disbiose durante a terapia para o câncer de cabeça e pescoço que esteja associada à mucosite oral?”. Resultados: 22 artigos foram selecionados em duas etapas de extração dos dados: artigos que avaliaram a microbiota bucal durante TCCP (n=13), e artigos que também focaram na mucosite oral (n=9). Conclusão: A evidência apresentada na literatura sugere associação de uma disbiose da microbiota bucal com a progressão e agravamento da mucosite oral induzida pela radiação. Entretanto, novos estudos padronizados são necessários para se definir o core microbiano para a doença

Evaluation of the presence and efficiency of potential probiotic bacteria in the gut of tilapia (Oreochromis niloticus) using the fluorescent in situ hybridization technique

The Fluorescent in situ Hybridization (FISH) technique was employed to enumerate potential probiotic and putative pathogenic bacteria in the gut of tilapia (Oreochromis niloticus). Bacteria used in the study were isolated from water, sediment and intestines of tilapia (Oreochromis niloticus) raised in an aquaculture system. These isolates were tested in vitro on antagonism tests against putative pathogenic bacteria (Aeromonas hydrofila, Enterococcus faecalis, Edwardsiella tarda, Pseudomonas fluorescens and Pseudomonas putida), also isolated fromthe same aquaculture system. Two isolates that inhibited largest number of pathogenic bacteria were identified by sequencing as Bacillus sp. and Enterococcus sp. and were added to the commercial feed (106 cells g−1) for in vivo tests. Treatments of the in vivo experiment were: 1) Control — fish fed with no added bacteria, 2) Bacil. — fish fed diets containing Bacillus sp.; 3) Enter. — fish fed diets containing Enterococcus sp., and 4) Bacil.+Enter. — fish fed diets containing Bacillus sp. and Enterococcus sp. (1:1). Each treatment consisted of four replicates with 15 juveniles of tilapia (O. niloticus — 16.74± 4.35 g e 9.82±0.85 cm). The experiment lasted for 30 days and at the end of this period, three fish from each tank were killed, and the intestines were taken for microbiological analysis by FISH technique, where Bacillus and Enterococcus, as well as two putative pathogenic bacteria (Aeromonas and Pseudomonas sp.) were quantified. Enterococcus sp. and Bacillus sp. were present in high number in the gut microbiota of fish. However, Bacillus sp., showed an increase in its abundance, indicating a successful incorporation of this potential probiotic bacteria into the tilapia gut microbiota. Furthermore, in the Bacil. treatment it was observed a significant reduction of Aeromonas and Pseudomonas sp. abundances compared with the other treatments. These results indicate that the FISH technique is a potential tool to characterize the dynamics of potential probiotic bacteria and their efficiency in the control of pathogenic bacteria

Longitudinal study on clinical and microbial analysis of periodontal status in pregnancy

Abstract This study was aimed to provide a longitudinal overview of the subgingival bacterial microbiome using fluorescence in situ hybridization (FISH) technique, in women in the second trimester of pregnancy (between 14 and 24 weeks), and 48 h and 8 weeks postpartum. Of 31 women evaluated during pregnancy, 24 returned for the 48-h and 18 for their 8-week exams postpartum. Probing depth (PD), bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected, and FISH was used to identify the numbers of eight periodontal pathogens. Friedman test was used to compare differences between follow-up examinations, followed by a multiple comparison test for a post hoc pairwise comparison. Clinically, a significantly greater number of teeth with PD = 4–5 mm were found during pregnancy than on postpartum examinations. Microbial analysis showed a statistically significant decrease in cell count over the study period for Prevotella nigrescens. P. intermedia, Campylobacter rectus, and Porphyromonas gingivalis also decrease, although not significantly, and Aggregatibacter actinomycetemcomitans increased. No significant changes were found for Fusobacterium nucleatum, Treponema denticola, or Tannerella forsythia. Our data demonstrate a change in the subgingival microbiota during pregnancy, at least for P. nigrescens

MICRORGANISMOS NO SEDIMENTO DE MARGENS OPOSTAS DO ESTUÁRIO DO RIO COREAÚ EM CAMOCIM/CE

O estuário do rio Coreaú possui uma das margens tangenciando a área urbana de Camocim, enquanto a outra tangencia a APA das Dunas da Ilha da Testa Branca. Com o objetivo de verificar os efeitos das atividades antrópicas na margem urbanizada, este trabalho analisou parâmetros físico-químicos e microbiológicos em ambas as margens. Análises de pH, temperatura, turbidez, oxigênio dissolvido e DBO5 foram realizadas na água. Amostras do sedimento foram utilizadas para quantificação de matéria orgânica e de bactérias heterotróficas, enumeração de coliformes, quantificação de células procarióticas e de bactérias patogênicas. Não houve diferença significativa para os parâmetros físico-químicos, exceto para matéria orgânica no sedimento, maior na margem urbanizada. A densidade de bactérias heterotróficas e de células procarióticas é maior na margem urbanizada. Os resultados indicaram que coliformes termotolerantes ocorrem apenas na margem urbanizada. Todos os taxa bacterianos patogênicos são encontrados em maior densidade na margem urbanizada, onde a densidade de E. coli é quase cinco vezes maior. Nossos resultados indicam que o descarte de águas residuárias está relacionado com a maior densidade de bactérias patogênicas no sedimento da margem urbanizada o que pode resultar em um problema de saúde pública

Salivary Periodontopathic Bacteria in Children and Adolescents with Down Syndrome

<div><p>Objective</p><p>To assess and compare salivary periodontopathic bacteria between groups of Down syndrome and non-Down syndrome children and adolescents.</p><p>Materials and Methods</p><p>This study included a sample of 30 Down syndrome children and adolescents (G-DS) and 30 age- and sex-matched non-Down syndrome subjects (G-ND). Clinical examination determined the gingival bleeding index (GBI) and plaque index. Unstimulated whole saliva samples were collected from all participants. The fluorescence <i>in situ</i> hybridization (FISH) technique identified the presence and density of eight periodontopathic bacteria in saliva. The statistical analysis included chi-square and Mann-Whitney <i>U</i> tests.</p><p>Results</p><p>In the G-DS group, bleeding on probing was more frequent (<i>p</i> = 0.037) and higher densities of <i>Campylobacter rectus</i> (<i>p</i> = 0.013), <i>Porphyromonas gingivalis</i> (<i>p</i> = 0.025), <i>Treponema denticola</i> (<i>p</i> = 0.026), <i>Fusobacterium nucleatum</i> (<i>p</i> = 0.013), <i>Prevotella intermedia</i> (<i>p</i> = 0.001) and <i>Prevotella nigrescens</i> (<i>p</i> = 0.008) were observed. Besides, in the G-DS, the densities of bacteria from the orange complex were significantly higher in the age group 3–7 years for <i>F</i>. <i>nucleatum</i> (<i>p</i> = 0.029), <i>P</i>. <i>intermedia</i> (<i>p</i> = 0.001) and <i>P</i>. <i>nigrescens</i> (<i>p</i> = 0.006). <i>C</i>. <i>rectus was</i> higher in the age group 8–12 years (<i>p</i> = 0.045).</p><p>Conclusion</p><p>The results showed that children and adolescents with Down syndrome have higher susceptibility to periodontal disease and number of periodontopathic bacteria.</p></div

Aliphatic hydrocarbon enhances phenanthrene degradation by autochthonous prokaryotic communities from a pristine seawater

The microbial diversity and functioning around oceanic islands is poorly described, despite its importance for ecosystem homeostasis. Here, we aimed to verify the occurrence of microbe-driven phenanthrene co-oxidation in the seawater surrounding the Trindade Island (Brazil). We also used Next-Generation Sequencing to evaluate the effects of aliphatic and polycyclic aromatic hydrocarbons (PAHs) on these microbial community assemblies. Microcosms containing seawater from the island enriched with either labelled (9^-14C) or non-labelled phenanthrene together with hexadecane, weathered oil, fluoranthene or pyrene, and combinations of these compounds were incubated. Biodegradation of phenanthrene-9^-14C was negatively affected in the presence of weathered oil and PAHs but increased in the presence of hexadecane. PAH contamination caused shifts in the seawater microbial community—from a highly diverse one dominated by Alphaproteobacteria to less diverse communities dominated by Gammaproteobacteria. Furthermore, the combination of PAHs exerted a compounded negative influence on the microbial community, reducing its diversity and thus functional capacity of the ecosystem. These results advance our understanding of bacterial community dynamics in response to contrasting qualities of hydrocarbon contamination. This understanding is fundamental in the application and monitoring of bioremediation strategies if accidents involving oil spillages occur near Trindade Island and similar ecosystems

Results of the gingival bleeding index.

<p>Results of the gingival bleeding index.</p