Navegando por Autor "Dias, Roberto Sousa"
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Item Association of inflammation, dyslipidemia, obesity and physical activity status in children(Motriz: Revista de Educação Física, 2016-04) Pereira, Patrícia Feliciano; Oliveira, Michelle Dias de; Dias, Roberto Sousa; Paula, Sérgio Oliveira de; Guedes, Juliano Magalhães; Mamêde Neto, José Bontempo; Ribeiro Andaki, Alynne Christian; Natali, Antônio José; Rogério, Alexandre de Paula; Mendes, Edmar LacerdaThe aim of this study was to verify the association between inflammatory biomarkers, dyslipidemia, obesity and physical activity status in 10-years old children. Ninety-four children participated in this study and were classified into eutrophic (n=36), overweight (n=34) or obese (n=24) according to their body mass index (BMI). The genic expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and chemokine C-C motif ligand 2 (CCL-2) mRNA; the serum concentration of high-density lipoprotein cholesterol (HDL-c) and triglycerides; BMI, percentage of body fat (% BF) and waist circumference; and the number of steps per day were determined. The expression of IL-6, TNF-α and CCL-2 were associated (p < 0.05) positively with serum triglycerides, BMI, % BF and waist circumference, and negatively with serum HDL-c. No association (p > 0.05) between pro-inflammatory biomarkers and number of steps per day was found.Item Bacteriophage isolated from sewage eliminates and prevents the establishment of Escherichia Coli Biofilm(Advanced Pharmaceutical Bulletin, 2018-02-20) Ribeiro, Karla Veloso Gonçalves; Ribeiro, Cleberson; Dias, Roberto Sousa; Cardoso, Silvia Almeida; Paula, Sérgio Oliveira de; Zanuncio, Jose Cola; Oliveira, Leandro Licursi deBiofilm growth exerts a negative impact on industry and health, necessitating the development of strategies to control. The objective of this work was study the lytic activity of the phage isolated from the sewage network in the formation and degradation of Escherichia coli biofilms. E. coli cultures were incubated in 96-well polystyrene microplates under controlled conditions to evaluate the biofilm formation. The E. coli cultures and established biofilms were treated with the suspensions of the vB_EcoM-UFV017 (EcoM017) bacteriophage obtained from sewage for 24 hours. The E. coli bacterial density was measured using absorbance at 600 nm and the biofilms were measured by crystal violet staining. Polystyrene coupons were used as support for Scanning Electron Microscopy and Confocal Microscopy to evaluate biofilm formation. The E. coli strains formed biofilms in polystyrene microplates after 48 hours’ incubation. The highest EcoM017 phage titer, in the prevention and degradation experiments, reduced the bacterial growth and the quantity of biofilm formed by E. coli in 90.0% and 87.5%, respectively. The minimum dose capable of reducing the biofilms of this bacterium was 101 PFU/mL after 24 hours. The preformed E. coli biofilm mass was reduced 79% post exposure to the phage in the degradation assay. Microscopic analysis confirmed the results obtained in the plates assays. The EcoM017 phage prevented biofilm formation and degraded the E. coli-established ones. The EcoM017 phage isolated from sewage can reduce bacterial attachment and lyse the E. coli associated biofilm cells, offering biotechnological potential applicability for this phage.Item The complete genome sequence of Trueperella pyogenes UFV1 reveals a processing system involved in the quorum-sensing signal response(Genome Announcements, 2017-07-20) Duarte, Vinícius da Silva; Treu, Laura; Campanaro, Stefano; Cynthia, Canedo da Silva; Dias, Roberto Sousa; Alessio, Giacomini; Corich, Viviana; Sérgio, Oliveira de PaulaWe present here the complete genome sequence of Trueperella pyogenes UFV1. The 2.3-Mbp genome contains an extremely interesting AI-2 transporter and processing system related to the quorum-sensing signal response. This specific feature is described in this species for the first time and might be responsible for a new pathogenic behavior.Item Conscientização dos produtores de leite da Zona da Mata Mineira sobre métodos de prevenção da mastite bovina e isolamento dos seus agentes etiológicos(Brazilian Journal of Sustainable Agriculture, 2011-12) Dias, Roberto Sousa; Duarte, Vinicius Silva; Favaro, Victor Lopes Ribeiro; Mantovani, Hilário Cuquetto; Silva, Cynthia Canêdo da; Silva, Eduardo de Almeida Marques da; Oliveira, Leandro Licursi de; Paula, Sérgio Oliveira DeA mastite causa perda da qualidade do leite e riscos à saúde dos consumidores em virtude da presença de resíduos de antibióticos e microrganismos patogênicos, além de sérios prejuízos econômicos tanto para o produtor quanto para a indústria de laticínios. O conhecimento referente aos agentes causadores da doença, à sua evolução clínica e a fatores relacionados com o estabelecimento da infecção deve ser colocado em prática em programas de controle e prevenção da doença, visando o treinamento dos produtores, principalmente em respeito ao manejo adequado de ordenha. Neste trabalho, buscamos conscientizar produtores de leite da Zona da Mata mineira sobre a importância do controle e prevenção de mastite bovina e determinar seus principais agentes etiológicos. Identificamos 3,3% de casos de mastite clínica, 15% de subclínica e 81,7% de tetos sadios em vacas leiteiras da região. Como principais agentes etiológicos, foram isolados o Staphylococcus aureus em 28,52% dos casos e o Staphylococcus sp., coagulase negativa, em 14,83%. Observamos também que poucos produtores da região possuem conhecimentos básicos sobre os métodos de prevenção e controle da mastite. Sendo assim, muitos carecem de programas de assistência técnica especializada, o que seria útil para o desenvolvimento de suas comunidades.Item Controle de biofilmes em membranas de osmose inversa através de bacteriófagos(Universidade Federal de Viçosa, 2014-09-03) Dias, Roberto Sousa; Paula, Sérgio Oliveira de; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4767540P4; http://lattes.cnpq.br/5264236284944155; Ramos, Javier Vega; http://lattes.cnpq.br/4360229725538200; Silva, Cláudio Mudado; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4727931T6; Merzel, Valéria Maia; Silva Júnior, Abelardo; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4771645P8Alguns segmentos industriais são conhecidos por produzir grandes quantidades de efluentes salinos, entre eles pode-se destacar o setor petroquímico. Com a crescente busca por tecnologias que permitam a reciclagem da água, os sistemas de osmose inversa (OI) tem ganhado grande atenção por parte do setor industrial e de pesquisadores em todo o mundo. As incrustações (fouling) são o principal entrave encontrado nesses sistemas por causarem redução expressiva no fluxo e podem ter diversas origens, sendo a bioincrustação, caracterizada pela formação de biofilme de origem microbiana na superfície da membrana, a mais importante. Neste trabalho foi avaliadaa capacidade do fago vB_AspP-UFV1, específico contra bactérias do gênero Arthrobacter, submetidoà analises morfológicas e moleculares e isolado a partir de sistemas de lodos ativados,no controle de biofilmeformado por bactérias obtidas da água de alimentação de sistemas de osmose inversa de refinarias de petróleo. Os resultados mostraram se tratar de um fago da família Podoviridae, ordem Caudovirales, com genoma de aproximadamente 22 Kb. As técnicas de cristal violeta e microscopia eletrônica de varredura demonstraram a capacidade do fago em reduzir a formação do biofilme na maioria das bactérias avaliadas, chegando a 87% de redução em alguns isolados, o que demonstra a viabilidade do uso de bacteriófagos como alternativa aos atuais métodos de controle microbiológico em sistemas industriais.Foi avaliada a formação de biofilme na superfície de membranas, operadas por 30 dias em um sistema piloto de osmose inversa, na filtração de efluente industrial proveniente de refinaria de petróleo. Foi observada a presença de biofilme espesso após 15 dias de operação, além da quase completa ausência de células viáveis no trigésimo dia . Foram isolados outros 5 fagos específicos contra as bactérias encontradas na água de alimentação do sistema de osmose inversa, visando assim a constituição de um coquetel fágico contendo fagos específicos e inespecíficos com potencial aplicação no controle de biofilme em sistemas de osmose inversa.Item Desulfovibrio alaskensis prophages and their possible involvement in the horizontal transfer of genes by outer membrane vesicles(Gene, 2019-06) Crispim, Josicelli Souza; Dias, Roberto Sousa; Laguardia, Clara Nogueira; Araújo, Larissa Cristina; Silva, Jéssica Duarte da; Vidigal, Pedro Marcus Pereira; Sousa, Maíra Paula de; Silva, Cynthia Canêdo da; Santana, Mateus Ferreira; Paula, Sérgio Oliveira de; Sousa, Maíra Paula deDesulfovibrio alaskensis is a Gram-negative bacterial species that belongs to the group of Sulphate Reducing Bacteria (SRB) and presents prophages in genomes, a common characteristic of the genus Desulfovibrio. Genetic material can be transported by outer membrane vesicles, however, no data regarding the production of these vesicles has been reported for D. alaskensis. To verify the expression of D. alaskensis prophages and their involvement with outer membrane vesicles, the DSM16109 strain was used. The DSM16109 strain had three prophages and presented reduced growth after mitomycin C addition when compared to the control culture. This reduction was accompanied by the presence of virus-like particles (VLPs), indicating mitomycin C dependent prophage induction. The increase in the number of cap gene copies and transcriptions of the three prophages was verified in the control sample, however, without the formation of VLPs. Prophage genes were identified in outer membrane vesicles from cultures treated and not treated with mitomycin C. DSM16109 prophages are expressed spontaneously but only in the presence of mitomycin C was it possible to observe VLP formation. Due to the genetic material detection from the prophages within outer membrane vesicles, this property may be related to the horizontal transfer of viral genes.Item Expression of the nifH gene in diazotrophic bacteria in Eucalyptus urograndis plantations(Canadian Journal of Forest Research, 2016-02) Silva, Marliane de Cássia Soares da; Mendes, Igor Rodrigues; Paula, Thiago de Almeida; Dias, Roberto Sousa; Paula, Sérgio Oliveira de; Silva, Cynthia Canedo; Bazzolli, Denise Mara Soares; Kasuya, Maria Catarina MegumiA large proportion of eucalypt plantations in Brazil are located in areas with low soil fertility. The actions of microorganisms are of great importance for the cycling of nutrients, including nitrogen (N), that are essential for plant metabolism. Denaturing gradient gel electrophoresis (DGGE) was used to monitor and identify the total and active microorganisms involved in the N cycle in both the soil and root systems of a forest of Eucalyptus urograndis with sections that were fertilized with N or unfertilized. Quantitative real-time PCR was used to examine the expression of the nifH gene in N-fixing bacteria present in both the soil and root systems. According to the DGGE analysis, in the total and active populations of N-fixing bacteria, the presence and expression of the nifH gene were influenced by the winter and summer seasons and (or) N fertilization, respectively. DGGE band sequencing from total DNA samples showed that the most abundant group of diazotrophic bacteria belonged to Alphaproteobacteria in both the soil and root systems. Quantitative real-time PCR revealed that nifH expression was higher in the soil samples, especially in those that did not receive N fertilization. The differences in the composition of the total and active diazotrophic populations highlight the importance of evaluating the active populations, because they are effectively responsible for the biogeochemical transformation of N and also control its' availability to plants.Item Isolamento, purificação e caracterização molecular de bacteriófagos específicos para Escherichia coli causadora de mastite bovina(Universidade Federal de Viçosa, 2011-06-29) Dias, Roberto Sousa; Zerbini Júnior, Francisco Murilo; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783743U5; Oliveira, Leandro Licursi de; http://lattes.cnpq.br/0578231392218162; Paula, Sérgio Oliveira de; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4767540P4; http://lattes.cnpq.br/5264236284944155; Mantovani, Hilário Cuquetto; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4727026Z7; Silva, Eduardo de Almeida Marques da; http://lattes.cnpq.br/9196320705613169A mastite bovina causa sérios prejuízos tanto ao produtor, quanto à indústria de produtos lácteos. É causada por diversos patógenos, divididos em dois grupos principais: ambientais e contagiosos. Enquanto o número de casos de mastite contagiosa vem diminuindo, os casos causados por patógenos ambientais aumentam, sendo a Escherichia coli o principal agente etiológico. Há um significativo aumento no número de novos casos causados por essa bactéria, sendo atualmente o principal responsável por casos de mastite que culminam com a morte do animal. O surgimento cada vez mais freqüente de linhagens multidroga resistentes e altamente patogênicas torna necessário o estudo de alternativas ao uso da antibioticoterapia. Assim os bacteriófagos, vírus que infectam bactérias e são altamente específicos, surgem como uma opção viável devido principalmente ao baixo custo e a rapidez com que é possível isolar um novo fago específico a linhagens resistentes. Estudos recentes da genética dos fagos e bacteriana tornam mais seguro o uso da fagoterapia, o que torna necessário estudos moleculares, visando obter dados com relação a possível utilização dos mesmos na fagoterapia. Neste contexto, foram isolados 15 bacteriófagos específicos para linhagens de Escherichia coli isoladas em rebanhos acometidos pela mastite bovina. Os isolados foram caracterizados com relação ao seu perfil protéico, evidenciando a presença de 2 proteínas de baixo peso molecular, composição genômica de DNA dupla fita com cerca de 44 kb. Com o objetivo de reduzir os custos e o tempo na obtenção de suspensões com alto grau de pureza, foi padronizada uma metodologia de purificação por cromatografia de troca iônica em um sistema FPLC, sendo possível a obtenção de suspensões virais com grau de pureza apreciável.Item Safety evaluation of the antimicrobial peptide bovicin HC5 orally administered to a murine model(BMC Microbiology, 2013) Paiva, Aline Dias; Fernandes, Kenner Morais; Dias, Roberto Sousa; Rocha, Alípio dos Santos; Oliveira, Leandro Licursi de; Neves, Clóvis Andrade; Paula, Sérgio Oliveira de; Mantovani, Hilário CuquettoBovicin HC5 is an antimicrobial peptide that shows a broad spectrum of activity and potential for biotechnological and therapeutic applications. To gain insight about the safety of bovicin HC5 application, the histological and immunostimulatory effects of orally administrated bovicin HC5 to BALB/c mice were evaluated. BALB/c mice were divided into three groups: negative control (NC group); mice given purified bovicin HC5 (Bov group); mice given ovalbumin (positive control, PC group; a murine model of enteropathy). The mice were initially pre-sensitized, and PBS, bovicin HC5 or ovalbumin were administered for 30 days by daily gavages. Histological and morphometric analysis were performed and the relative expression of cytokines was analyzed by real-time RT-PCR. The oral administration of bovicin HC5 to BALB/c mice reduced weight gain and caused alterations in the small intestine, although absorptive changes have not been detected. The number of total goblet cells and the mucopolysaccharides production were not affected by bovicin HC5 administration. A hypertrophy of Paneth cells and an increase in the number of mitotic cells were observed in Bov group, while the number of mast cells remained unaltered. Increased expression of TNF-α, INF-γ and IL-12 was observed in the small intestine upon bovicin HC5 administration. Bovicin HC5 has only minor effects on intestinal permeability and did not elicit an allergenic response upon oral administration to animal models. Considering the low in vivo toxicity of bovicin HC5, it might be a good candidate for enteral applications.Item Screening and characterization of prophages in Desulfovibrio genomes(Scientific Reports, 2018) Crispim, Josicelli Souza; Dias, Roberto Sousa; Vidigal, Pedro Marcus Pereira; Sousa, Maíra Paula de; Silva, Cynthia Canêdo da; Santana, Mateus Ferreira; Paula, Sérgio Oliveira deBacteria of the genus Desulfovibrio belong to the group of Sulphate Reducing Bacteria (SRB). SRB generate significant liabilities in the petroleum industry, mainly due to their ability to microbiologically induce corrosion, biofilm formation and H2S production. Bacteriophages are an alternative control method for SRB, whose information for this group of bacteria however, is scarce. The present study developed a workflow for the identification of complete prophages in Desulfovibrio. Poly-lysogenesis was shown to be common in Desulfovibrio. In the 47 genomes analyzed 53 complete prophages were identified. These were classified within the order Caudovirales, with 69.82% belonging to the Myoviridade family. More than half the prophages identified have genes coding for lysozyme or holin. Four of the analyzed bacterial genomes present prophages with identity above 50% in the same strain, whose comparative analysis demonstrated the existence of colinearity between the sequences. Of the 17 closed bacterial genomes analyzed, 6 have the CRISPR-Cas system classified as inactive. The identification of bacterial poly-lysogeny, the proximity between the complete prophages and the possible inactivity of the CRISPR-Cas in closed bacterial genomes analyzed allowed the choice of poly-lysogenic strains with prophages belonging to the Myoviridae family for the isolation of prophages and testing of related strains for subsequent studies.Item Temperature modulates the production and activity of a metalloprotease from Pseudomonas fluorescens 07A in milk(Journal of Dairy Science, 2018-02) Alves, Maura P.; Salgado, Rafael L.; Eller, Monique R.; Dias, Roberto Sousa; Paula, Sérgio Oliveira de; Carvalho, Antonio Fernandes deThis work evaluated the expression and activity of a metalloprotease released by Pseudomonas fluorescens 07A in milk. Low relative expression of the protease by the strain was observed after incubation for 12 h at 25°C while the strain was in the logarithmic growth phase. After 24 h, protease production significantly increased and remained constant for up to 48 h, a time range during which the strain remained in the stationary phase. Conversely, at refrigeration temperatures, at 12 h the strain was still in the lag phase and expressed the protease at higher levels than when the logarithmic phase was reached. Casein fractions were highly degraded by P. fluorescens 07A, the purified protease, and the bacterial pellet on d 7 of incubation at 25°C and to a lesser extent at 10°C for the sample incubated with the bacterium. Heat treatment at 90°C for 5 min completely inactivated the proteolytic activity of the purified protease and the bacterial pellet. This work contributes to the knowledge about the conditions of milk storage that influence the production and activity of this extracellular metalloprotease. The results demonstrate the need to find alternative strategies to control the synthesis and activity of proteolytic enzymes in the dairy industry to ensure the quality of processed products.