Tesi sul tema "Microbiologly"
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Lombard, Bertrand. "Les essais inter-laboratoires en microbiologie des aliments Inter-laboratory studies in food microbiology". Phd thesis, INAPG (AgroParisTech), 2004. http://pastel.archives-ouvertes.fr/pastel-00001258.
Testo completoKeltjens, Herman Michiel Antonius Marie. "Microbiology and preventive treatment of root surface caries Microbiologie en preventieve behandeling van tandwortelcariës /". Helden-Panningen : De Gouden Leeuv Drukkerij B.V, 1988. http://catalog.hathitrust.org/api/volumes/oclc/19650028.html.
Testo completoText in English with a summary in Dutch. "Een wetenschappelijke proeve op het gebied van geneeskunde en tandheelkunde." Includes bibliographical references.
Badia, Palacín Josefa. "Clonación y caracterización del operon de la ramnosa de Escherichia coli". Doctoral thesis, Universitat de Barcelona, 1987. http://hdl.handle.net/10803/672820.
Testo completoBridson, Eric Youlden. "Quantal microbiology". Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312059.
Testo completoOsman, Shaiesta. "Oral microbiology". Thesis, University of North Texas, 1998. http://catalog.hathitrust.org/api/volumes/oclc/48128254.html.
Testo completoVera, Garcia Rodrigo Elizardo. "Microbiología del caracol Helix aspersa Müller. Aplicaciones biotecnológicas para su mejoramiento sanitario con impacto en su comercialización". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/399849.
Testo completoThe Heliciculture is defined as the full life cycle breeding of snails. The land snail Helix aspersa Müller is the most used in different European regions as food, and it stand up for its high prolificacy and adaptability to the environment capacity. The breeding of snails is a livestock activity, and is not exempt from the manifestation of pathological processes of microbiological origin, that cause production losses. Currently, the Heliciculture aims at the marketing of quality snail, subjected to strict health and zootechnical controls to ensure the safety of this food. The objectives of this thesis are to optimize and/or create methodologies that facilitate the correct administration of the probiotic Lactobacillus plantarum Ca7 strain, which contributes to improve the health status of farms, intended for breeding and fattening land snail Helix aspersa Müller. The obtained results indicated that, the contamination present on a farm dedicated to snail reproduction, is associated with the microorganism in the intestinal microbiota of animals, mainly the Enterobacteriaceae Family, and the microbiota change because of contaminated feed consumption. The L. plantarum Ca7 studies, indicated that changes in the MRS culture medium, incubation parameters, and those involved in the lyophilization process, allow the improvement of the biomass production, increase of the lyophilized strain concentration, and the establishment of optimal storage conditions of freeze-dried cultures. For the use of an agitation system incorporating a culture of L. plantarum Ca7 to manage snails through irrigation water, it’s better to start whit no-lyophilized cultures, mixed with well water to ensure the survival of the strain and the safety of the preparation during the snails hydration. Concerning the use of the strain supernatant, observation showed that it possesses inhibitory properties on growth of pathogenic microorganisms and Staphylococcus aureus biofilm formation, also if this fraction is lyophilized, that increases its inhibitory properties, highlighting the effect on Pseudomonas aeruginosa. It is possible to incorporate this one to the feed in its lyophilized form without losing its inhibitory properties. In the laboratory, after the administration of the enriched with L. plantarum Ca7 feed to different age snails, the results indicated that this food alters the microbiota, prevents mortality of snails, and improves the microbiological quality of the feed. Based on these results, we can indicate that the administration of the L. plantarum Ca7 strain to snails, and its supernatant for contaminant microorganism control, present in the Heliciculture, would be able to help improve the sanitary livestock through the prevention of diseases of microbial origin, modification of the intestinal microbiota, and ameliorate the microbiological quality of the feed. Which leads to a productive improvement during snail breeding, and delivers added value to the final product, with consequent impact on marketing.
Marí, Marí Teresa. "Changes in soil biodiversity and activity along management and climatic gradients". Doctoral thesis, Universitat de Lleida, 2017. http://hdl.handle.net/10803/457976.
Testo completoLos llamados "rangelands" son áreas sin cultivar, ampliamente pastoreadas por animales domésticos y salvajes, actualmente amenazados por los cambios climático y de uso del suelo. Los microorganismos del suelo tienen un papel clave tanto en la descomposición como en diversos procesos del ecosistema, por lo que composición y función de la comunidad microbiana han sido utilizados durante mucho tiempo como índices de fertilidad del suelo. Los rangelands europeos y africanos comparten un origen antropogénico común, pero el clima y la gestión del suelo les afectan de una manera diferente. Es por ello que esta tesis pretende analizar la comunidad microbiana de ambos tipos de ecosistemas, a fin de observar los efectos de algunas de las amenazas comunes desde una perspectiva más global. Mientras que el sobrepastoreo demostró tener el efecto más perjudicial sobre la función microbiana en suelos kenianos, se encontró un efecto más fuerte del clima sobre los prados europeos. Los hongos y las bacterias covariaron a lo largo de gradientes altitudinales y climáticos, pero la comunidad bacteriana mostró una recuperación más rápida después de las perturbaciones biológicas y físico-químicas del suelo. Este conjunto de estudios añade nuevos conocimientos sobre la estructura y función de los rangelands africanos y europeos, e invita a explorar nuevas líneas de investigación que incluyan tanto bacterias como hongos en el estudio de la comunidad microbiana del suelo.
Rangelands are uncultivated areas extensively grazed by wild and domestic animals, currently threatened by land use and climatic changes. Soil microorganisms play a key role in decomposition and several ecosystem processes and the composition and function of the microbial community have been long used as indices of soil fertility. African and European rangelands share a common anthropogenic origin, but climate and management affect them in a different way. That is why this thesis aimed to analyze the microbial community of both in order to observe the effects of some common threats from a more global perspective. While overgrazing proved to have the most detrimental effect on the soil microbial function in Kenyan soils, a stronger effect of climate was found to affect European grasslands. Fungi and bacteria co-varied along altitudinal and climatic gradients, but the bacterial community showed a fast recovery after biological and soil physico-chemical disturbances. This group of studies adds new knowledge on the structure and function of the African and European rangelands, and invite to explore new lines of research including both fungal and bacterial consortia when studying the soil microbial community.
Huedo, Moreno Pol. "Fatty acid-mediated quorum sensing systems in stenotrophomonas maltophilia". Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/285570.
Testo completoFatty-acid mediated Quorum Sensing (QS) systems have aroused considerably interest in the last years since it has been reported that many important bacterial pathogens use these communication systems to regulate virulence-related functions. It is known that Stenotrophomonas maltophilia presents the DSF (Diffusible Signal Factor) QS system, which is controlled by components that are encoded in the rpf cluster (Regulation of Pathogenicity Factors). However, the mechanisms by which S. maltophilia synthesize and sense as well as the biological functions that are under control of DSF-QS remain unclear. Here, we have first demonstrated that two populations of S. maltophilia can be distinguished depending on the rpf cluster (rpf-1 or rpf-2) they harbour. Each variant cluster differs basically in the genes that encode for the synthase RpfF and the sensor RpfC. Moreover, we have observed that there exist a full association between both components, existing the pair RpfF-1/RpfC-1 for the rpf-1 variant and RpfF-2/RpfC-2 for the rpf-2 variant. In addition, we have demonstrated that only strains harbouring the rpf-1 variant produce detectable levels of DSF and it seems to regulate bacterial motility, biofilm development and virulence. On the other hand, strains harbouring the rpf-2 variant need extra copies of rpfF-2 or the absence of rpfC-2 to achieve detectable levels of DSF. In this case, DSF-QS seems to control only some virulence-related phenotypes in very specific environments (e.g., zebrafish infection). We also have shown that DSF is produced in a positive feedback-manner in S. maltophilia, and also, that both rpf-variant groups act synergistically in the DSF production and virulence ability of the whole population. In addition, we have observed that while RpfC-1 is a promiscuous sensor that liberates free active-RpfF-1 -with the subsequent DSF synthesis- upon detection not only DSF, but also saturated medium-length fatty acids, the sensor RpfC-2 only allows activation of RpfF-2 upon detection of DSF-itself, indicating that this sensor component is much more specific. Here, we further report that the cis-DA (cis-decenoic acid) QS system recently described in Pseudomonas aeruginosa is also present in S. maltophilia, and it regulates various virulence factors. In this line, we have preliminary characterized two important components in the biosynthesis of cis-DA, the enoyl-CoA hydratases (ECH) Smlt0266 and Smlt0267. We have observed that while the mutation in the putative synthase smlt0266 lead to alteration basically in biofilm formation, the mutation of the alternative ECH smlt0267 results in a drastic effect in many virulence-related behaviours such as biofilm formation, bacterial motility, exopolysaccharide production, antibiotic resistance and virulence. Similar results have been obtained for the mutants in the orthologous P. aeruginosa genes ∆dspI and ∆dspII. These results further support the significance of these two ECH, in addition to DSF-QS system, in virulence regulation of S. maltophilia and provide new interesting targets for developing new antimicrobial therapies against this potential human pathogen.
Aljohny, Bassam Ouda. "Studies on silicon microbiology". Thesis, University of Sheffield, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548645.
Testo completoWhite, Lorraine. "The microbiology of death". Thesis, University of Sheffield, 2009. http://etheses.whiterose.ac.uk/10361/.
Testo completoKehe, Jared Scott. "Massively parallel combinatorial microbiology". Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127886.
Testo completoCataloged from PDF version of thesis.
Includes bibliographical references (pages 203-216).
Reductionist biology of the 20th century rooted pure culture methods and antibiotics as pillars of humankind's interaction with microbiology, igniting a revolution in medicine and biotechnology. The revolution was not without cost. By overlooking complex biological interactions, it introduced new problems--from the sharp rise in immune disorders to the antibiotic resistance crisis--that 21st century tools must address. While 'omics methods have fundamentally expanded our understanding of biological complexity, we lack a generalized method for measuring how the parts of a complex system, such as the individual strains of a microbial community, interact with each other. In this thesis, I present kChip, a new platform for constructing massively parallel combinatorial arrays of these parts in order to measure their interactions directly. I describe how kChip has been used to reveal patterns in microbial community assembly, unearth minimal microbial combinations with desirable functions, and screen for compounds that potentiate antibiotic activity. I demonstrate how kChip can advance the development of new technologies like microbial consortia and combinatorial drug therapies.
by Jared Scott Kehe.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Biological Engineering
Carrasquilla, Gallego Marc. "El microbioma del agroecosistema y su importancia en la agricultura sostenible". Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671606.
Testo completoLas plantas establecen interacciones con multitud de microorganismos que influyen en su desarrollo y supervivencia, de manera que estas podrían ser consideradas como metaorganismos, la planta depende de su microbiota para obtener nutrientes y como escudo contra enfermedades, entre otros, y a cambio, la planta le proporciona nutrientes en forma de exudados que pueden representar hasta un 21% del carbono que fija fotosintéticamente. Dichas interacciones, tanto con la microbiota de las filosfera como la de la rizosfera, son cruciales para la salud de las plantas, su adaptación al estrés biótico y abiótico, así como un elemento básico para conseguir una agricultura sostenible. En este estudio se ha caracterizado la microbiota bacteriana y fúngica asociada a la filosfera de dos árboles frutales, Malus domestica y Pyrus communis, a lo largo de su desarrollo fenológico, mediante tres aproximaciones moleculares diferentes. Los resultados obtenidos son equivalentes para las tres metodologías en cuanto a la composición taxonómica de las comunidades microbianas. Se ha definido el core del microbioma para ambas especies vegetales. Dentro de este, cabe resaltar la presencia de género Deinococcus en el core del bacterioma, a diferencia de estudios previos y se ha descrito por primera vez el core del micobioma de la filosfera. Se han establecido dos modelos para explicar la sucesión microbiana a lo largo del ciclo vegetativo del árbol, así como biomarcadores representativos para cada uno de ellos. Por otro lado, se ha descrito el microbioma de la rizosfera de suelos conductivos y supresivos para el nematodo fitopatógeno Meloidogyne spp., observándose marcadas diferencias entre ellos. Se ha caracterizado el core, destacando la presencia de Sporosarcina, Pseudombrophila, Chaetomaiaceae, Cladosporium y Morteriellaceae, como característicos en suelos supresivos. Respecto a los biomarcadores indicativos de la condición de supresividad se han identificado los siguientes taxones, Acidobacteria, Actinobacteria, Firmicutes, Cladosporium, Pyrenochaeta, Arachniotus, Pseudogymnoascus, Pseudombrophila y Morteriella. Finalmente, se realizó unos ensayos en maceta para valorar el impacto del agente de biocontrol contra Meloidogyne incognita, Trichoderma asperellum, sobre la microbiota de la rizosfera de Solanum lycopersicum, donde además se tenían en cuenta dos variables, la tipología del suelo supresivo y la variedad vegetal (resistente o sensible al patógeno). Los resultados obtenidos han puesto de manifiesto que los factores determinantes en la composición taxonómica de la microbiota del suelo rizosferico son en orden decreciente de importancia, la tipología del suelo y la variedad vegetal. No se ha podido valorar el efecto de Trichoderma asperellum dada la falta de prevalencia de este agente de biocontrol en el suelo.
Plants establish interactions with a multitude of microorganisms that influence their development and survival, so that these could be considered as meta-organisms, the plant depends on its microbiota to obtain nutrients and as a shield against diseases, among others, and in return, the plant provides it with nutrients as exudates, that can represent up to 21% of the carbon it fixes photosynthetically. Such interactions, both with the phyllosphere and rhizosphere microbiota, are crucial for the health of plants, their adaptation to biotic and abiotic stresses, as well as a basic element for achieving sustainable agriculture. In this study, the bacterial and fungal microbiota associated with the phyllosphere of two fruit trees, Malus domestica and Pyrus communis, have been characterized throughout their phenological development, using three different molecular approaches. The results obtained are equivalent for the three methodologies regarding the taxonomic composition of the microbial communities. The core of the microbiome has been defined for both plant species. Within this, it is worth to highlight the presence of the genus Deinococcus in the core of the bacteriome, unlike previous studies and the core of the mycobiome of the phyllosphere has been described for the first time. Two models have been established to explain the microbial succession along the vegetative cycle of the tree, as well as representative biomarkers for each of them. On the other hand, the rhizosphere microbiome of conductive and suppressive soils has been described for the phytopathogenic nematode Meloidogyne spp., obbserving marked differences between them. The core has been characterized, highlighting the presence of Sporosarcina, Pseudombrophila, Chaetomaiaceae, Cladosporium and Morteriellaceae, as characteristic in suppressive soils. Regarding the biomarkers indicative of the suppressive condition, the following taxa have been identified: Acidobacteria, Actinobacteria, Firmicutes, Cladosporium, Pyrenochaeta, Arachniotus, Pseudogymnoascus, Pseudombrophila and Morteriella. Finally, a pot assay was carried out to assess the impact of the biocontrol agent against Meloidogyne incognita, Trichoderma asperellum, on the microbiota of the rhizosphere of Solanum lycopersicum, where two variables were also considered, the type of suppressive soil and the variety plant (resistant or sensitive to the pathogen). The results obtained have shown that the determining factors in the taxonomic composition of the rhizospheric soil microbiota are, in decreasing order of importance, the typology of the soil and the vegetable variety. The effect of Trichoderma asperellum could not be evaluated given the lack of prevalence of this biocontrol agent in the soil.
Universitat Autònoma de Barcelona. Programa de Doctorat en Microbiologia
Lima, Raquel Maria Torres. "Relevance of Latent EBV infection in drug response of burkitt lymphoma cells". Doctoral thesis, Faculdade de Farmácia da Universidade do Porto, 2009. http://hdl.handle.net/10216/53912.
Testo completoFreitas, Ana Raquel Pinho. "Ecology and evolution of antimicrobial resistance in Enterococcus: a multilayered molecular approach with emphasys in the plasmid diversity". Doctoral thesis, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63801.
Testo completoLima, Raquel Maria Torres. "Relevance of Latent EBV infection in drug response of burkitt lymphoma cells". Tese, Faculdade de Farmácia da Universidade do Porto, 2009. http://hdl.handle.net/10216/53912.
Testo completoFreitas, Ana Raquel Pinho. "Ecology and evolution of antimicrobial resistance in Enterococcus: a multilayered molecular approach with emphasys in the plasmid diversity". Tese, Faculdade de Farmácia da Universidade do Porto, 2010. http://hdl.handle.net/10216/63801.
Testo completoGrant, Irene Ruth. "The microbiology of irradiated pork". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335332.
Testo completoRobinson, Tobin. "The microbiology of food microenvironments". Thesis, Cardiff University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387586.
Testo completoAthukorala, Arachchi Seneviratne Chaminda Jayampath. "Molecular microbiology of candida biofilms". Thesis, Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B4068751X.
Testo completoZúñiga, Olate Roberto Aquiles. "Estudios funcionales y estructurales de la triptofanil tRNA sintetasa de Acidithiobacillus ferrooxidans". Tesis, Universidad de Chile, 2002. http://www.repositorio.uchile.cl/handle/2250/106690.
Testo completoShinya, Thaís Yumi [UNESP]. "Produção, purificação e ação antimicrobiana do extrato fúngico do Trichosporon asahii". Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/94853.
Testo completoDevido à necessidade de obtenção de novas moléculas com ação antimicrobiana, o presente trabalho visou investigar a capacidade antagônica do extrato produzido pelo fungo Trichosporon asahii. O extrato foi obtido pela fermentação do fungo em fermentador de bancada 7L, a 28°C por 72 horas. O caldo fermentado foi centrifugado a 2500 rpm por 20 minutos, sendo o sobrenadante a fração denominada extrato bruto, que foi seco em estufa (37°C) e ressuspendido em água destilada, para testes de ação antimicrobiana contra os micro-organismos Candida albicans, Malassezia pachydermatis, Trichophyton mentagrophytes, Pseudomonas aeruginosa ATCC 9027 e ATCC 27853, Xanthomonas campestris pv campestris. O teste de sensibilidade foi o de Concentração Bactericida e Fungicida Mínima (CBM e CFM), através da macrodiluição em tubos e plaqueamento. Numa segunda etapa, o extrato bruto foi submetido a uma separação líquido-líquido utilizando os solventes hexano e diclorometano, obtendo-se frações aquosa e orgânica. Numa última etapa de purificação, o extrato diclorometânico passou por uma cromatografia de troca-iônica, cromatografia em sílica gel e precipitação com sulfato de amônio. Foram calculados alguns parâmetros de fermentação do T. asahii, através dos métodos de quantificação de açúcares redutores, pH, viabilidade e brotamento das leveduras e quantidade total de células. O teste de sensibilidade do extrato bruto demonstrou apenas atividade antibacteriana (30000 µg/mL sobre P. aeruginosa ATCC 9027, 33000 µg/mL sobre P. aeruginosa ATCC 27853 e 75000 µg/mL sobre X. campestris). Observou-se uma diminuição da CBM para a fração diclorometânica (17500 µg/mL sobre P. aeruginosa ATCC 9027, 20000 µg/mL sobre P. aeruginosa ATCC 27853 e 60000 µg/mL sobre X. campestris). Na pré-purificação, o método que demonstrou maior eficácia para o propósito...
Nowadays there is a demand for new natural molecules that may contribute to the control of pathogenic microorganisms. In this study it was aimed to investigate the antimicrobial ability of the broth produced by the culture of the fungus Trichosporon asahii. The extract was obtained by fermentation of T. asahii bench 7 L fermenter at 28° C for 72 hours. The fermented broth was centrifuged at 2500 rpm for 20 minutes, and the supernatant fraction termed crude extract, which was dried in oven (37° C) and resuspended in distilled water for testing antimicrobial activity against the microorganisms Candida albicans, Malassezia pachydermatis, Trichophyton mentagrophytes, Pseudomonas aeruginosa ATCC 9027 and ATCC 27853 and Xanthomonas campestris pv campestris. The method used for quantification of antibiotic was the Minimum Bactericidal and Fungicidal Concentration (MBC and MFC) by macrodilution tubes and plating. In a second stage, the crude extract was subjected to liquid-liquid separation using dichloromethane and hexane solvents to yield aqueous and organic fractions. A new purification step from the dichloromethanic fraction passed through an ion exchange chromatography, silica gel chromatography and by precipitation with ammonium sulfate. It was also calculated some fermentation parameters of T. asahii by analytical methods for quantifying reducing sugars, pH, cell viability, budding yeasts and total cells. The MBC test showed only antibacterial activity (33,000 µg/mL for P. aeruginosa ATCC 27853, 30,000 µg/mL for P. aeruginosa ATCC 9027 and 75,000 µg/mL for X. campestris). There was a decrease in the MBC for the dichloromethanic fraction (20,000 µg/mL for P. aeruginosa ATCC 27853, 17,500 µg/mL for P. aeruginosa ATCC 9027 and 60,000 µg/mL for X. campestris). In the pre-purification step, the ion exchange chromatography was the more effective method... (Complete abstract click electronic access below)
Shinya, Thaís Yumi. "Produção, purificação e ação antimicrobiana do extrato fúngico do Trichosporon asahii /". São José do Rio Preto : [s.n.], 2012. http://hdl.handle.net/11449/94853.
Testo completoBanca: Ary Fernandes Júnior
Banca: Valéria Marta Gomes Lima
Resumo: Devido à necessidade de obtenção de novas moléculas com ação antimicrobiana, o presente trabalho visou investigar a capacidade antagônica do extrato produzido pelo fungo Trichosporon asahii. O extrato foi obtido pela fermentação do fungo em fermentador de bancada 7L, a 28°C por 72 horas. O caldo fermentado foi centrifugado a 2500 rpm por 20 minutos, sendo o sobrenadante a fração denominada extrato bruto, que foi seco em estufa (37°C) e ressuspendido em água destilada, para testes de ação antimicrobiana contra os micro-organismos Candida albicans, Malassezia pachydermatis, Trichophyton mentagrophytes, Pseudomonas aeruginosa ATCC 9027 e ATCC 27853, Xanthomonas campestris pv campestris. O teste de sensibilidade foi o de Concentração Bactericida e Fungicida Mínima (CBM e CFM), através da macrodiluição em tubos e plaqueamento. Numa segunda etapa, o extrato bruto foi submetido a uma separação líquido-líquido utilizando os solventes hexano e diclorometano, obtendo-se frações aquosa e orgânica. Numa última etapa de purificação, o extrato diclorometânico passou por uma cromatografia de troca-iônica, cromatografia em sílica gel e precipitação com sulfato de amônio. Foram calculados alguns parâmetros de fermentação do T. asahii, através dos métodos de quantificação de açúcares redutores, pH, viabilidade e brotamento das leveduras e quantidade total de células. O teste de sensibilidade do extrato bruto demonstrou apenas atividade antibacteriana (30000 µg/mL sobre P. aeruginosa ATCC 9027, 33000 µg/mL sobre P. aeruginosa ATCC 27853 e 75000 µg/mL sobre X. campestris). Observou-se uma diminuição da CBM para a fração diclorometânica (17500 µg/mL sobre P. aeruginosa ATCC 9027, 20000 µg/mL sobre P. aeruginosa ATCC 27853 e 60000 µg/mL sobre X. campestris). Na pré-purificação, o método que demonstrou maior eficácia para o propósito... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Nowadays there is a demand for new natural molecules that may contribute to the control of pathogenic microorganisms. In this study it was aimed to investigate the antimicrobial ability of the broth produced by the culture of the fungus Trichosporon asahii. The extract was obtained by fermentation of T. asahii bench 7 L fermenter at 28° C for 72 hours. The fermented broth was centrifuged at 2500 rpm for 20 minutes, and the supernatant fraction termed crude extract, which was dried in oven (37° C) and resuspended in distilled water for testing antimicrobial activity against the microorganisms Candida albicans, Malassezia pachydermatis, Trichophyton mentagrophytes, Pseudomonas aeruginosa ATCC 9027 and ATCC 27853 and Xanthomonas campestris pv campestris. The method used for quantification of antibiotic was the Minimum Bactericidal and Fungicidal Concentration (MBC and MFC) by macrodilution tubes and plating. In a second stage, the crude extract was subjected to liquid-liquid separation using dichloromethane and hexane solvents to yield aqueous and organic fractions. A new purification step from the dichloromethanic fraction passed through an ion exchange chromatography, silica gel chromatography and by precipitation with ammonium sulfate. It was also calculated some fermentation parameters of T. asahii by analytical methods for quantifying reducing sugars, pH, cell viability, budding yeasts and total cells. The MBC test showed only antibacterial activity (33,000 µg/mL for P. aeruginosa ATCC 27853, 30,000 µg/mL for P. aeruginosa ATCC 9027 and 75,000 µg/mL for X. campestris). There was a decrease in the MBC for the dichloromethanic fraction (20,000 µg/mL for P. aeruginosa ATCC 27853, 17,500 µg/mL for P. aeruginosa ATCC 9027 and 60,000 µg/mL for X. campestris). In the pre-purification step, the ion exchange chromatography was the more effective method... (Complete abstract click electronic access below)
Mestre
Jeffery, Simon. "The microbiology of arable soil surfaces". Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/2245.
Testo completoAl-Wajeeh, Khaled Mohsen. "Studies on the microbiology of silicon". Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/10225/.
Testo completoFrau, Alessandra. "Molecular microbiology of hydrocarbon polluted groundwater". Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.676470.
Testo completoNgo, Chinh Chung. "Microbiology and Immunology of Otitis Media". Thesis, Griffith University, 2016. http://hdl.handle.net/10072/365263.
Testo completoThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Medical Science
Griffith Health
Full Text
TRINCHERA, MARIACRISTINA. "INNOVATION OF DIAGNOSTIC SYSTEM IN MICROBIOLOGY". Doctoral thesis, Università di Siena, 2016. http://hdl.handle.net/11365/1010583.
Testo completoReffatti, Leonardo. "Diferenciação da origem geográfica de vinhos elaborados com uvas de três regiões vitícolas de Santa Catarina através de análises isotópicas e elementos minerais". reponame:Repositório Institucional da UCS, 2016. https://repositorio.ucs.br/handle/11338/2443.
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Wine origin and typicity are important issues and big interest for producers, consumers and traders. Both are linked to the achievement of wine recognition by the consumer market. Brazil has continental dimensions and a wide winegrowing diversity regions, each one with unique characteristics. Santa Catarina occupies the fourth state place in Brazilian surface area with vineyards, on the other hand, it´s the second in wine production, showing a potential for this activity. In this study, samples of three regions in Santa Catarina were collected aiming differ them by geographic localization, using oxygen isotopic ratio analysis (18O) of water, carbon isotopic ratio (13C) of ethanol, and mineral 85Rb and 88Sr wine content. Varietal Carbernet Sauvignon and Merlot wines were elaborated by microvinifications, vintage 2013, from the regions: Carbonífera, Vale do Rio do Peixe and Planalto Serrano de São Joaquim. Isotopic analysis of oxygen and carbon were performed by mass spectrometry isotope ratio (IRMS), and mineral elements by inductively coupled plasma-mass spectrometry (ICPMS). Wine water average values of 18O in Cabernet Sauvignon wines were efficient to differ wines from the three regions, demonstrating higher average values for Vale do Rio do Peixe region (3,31‰), followed by Carbonífera region (1,48‰), and Planalto Serrano de São Joaquim region showed negative values (-2,70‰). Similarly to Cabernet Sauvignon, wine water average values of 18O in Merlot wines were effective in differentiating just two regions, the higher values were exhibited for Vale do Rio do Peixe (3,72‰), and lower values for Planalto Serrano de São Joaquim (-2,76‰). Oxygen isotopic ratio depends mainly of whether conditions during grape maturation and harvest. Wine ethanol average values for 13C in Cabernet Sauvignon wines were not able to differ the three regions of Santa Catarina, however average values found to Merlot wines were able, evincing more negative values in Planalto Serrano de São Joaquim (-29,55‰), and less negative to Vale do Rio do Peixe (-28,67‰). Further on the geographic differentiation, the 13C showed potential to differentiate varieties inside a region. In Vale do Rio do peixe region, wine ethanol average 13C for Cabernet Sauvignon wines (-29,80‰) showed difference to Merlot wines (-28,57‰), the same differentiation occurred to Planalto Serrano de São Joaquim region, where Cabernet Sauvignon wines demonstrated values of (-30,47‰) and Merlot wines (-29,55‰). A wide range of mineral elements such as B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Nb, Cd, Sb, Cs, Ba and Pb were quantified to geographic differentiation between the studied regions. None of the mineral elements individually studied in this work allowed the differentiation of the three regions studied for Cabernet Sauvignon wines. However, the results for Mg, Al, Ca, Mn, Se, Rb, Sr, Zr, Nb, Cs and Ba differentiated at least one of the studied regions in Cabernet Sauvignon wines, it was also possible to differentiate the two regions studied in Merlot wines. A group of 18O, B, Mg, Al, V, Mn, Co, Cu, Se, Rb, Sr, Cd e Sb results classified the three regions by 100%.
Oliveira, Daniel Paulo de. "Produção de amilase por Bacillus licheniformis utilizando meios de baixo custo". Universidade Católica de Pernambuco, 2007. http://www.unicap.br/tede//tde_busca/arquivo.php?codArquivo=186.
Testo completoThe enzymatic biotechnology industry is growing up progressively in the last decades with the utilization e production of diverse microbial enzymes. Amylases are enzymes which hydrolyze starch molecules to give diverse products including dextrin's and progressively glucose units. They play a wide field of applications. In food industries, in beer industry and others fermented drinks, in cereal for baby's food and animal feed, in paper and cellulose industry, textile industry, in detergent and cleaning products industry, in chemical and pharmaceutical industry. Screening was carrying out in solid media to amylase production in 5 strains isolated from contaminated ambient by petroleum in different temperatures (28 C and 37 C), respectively. The results obtained evidenced that the isolated Bacillus licheniformis UCP 1009 showed the halo formation characteristically of the 55 mm to amylase, after 72 hours of incubation. After the selection of the microorganism, fermentations was carrying out to amylase production, replacing the soluble starch, by corn starch and potato starch, trough of factorial planning 23 with 4 central's points, having a amylase's production as a answering variable, during 96 hours. The microbial growth profile was established, the pH, the glucose consumption by the DNS and determination of specific enzyme activity. The results obtained evidenced that the corn starch shown an specific activity of 0.756 U/mg, at a pH of 8.82 and a enzymatic activity of amylase 0.99 U/dL, showing a industrial potential
Pereira, Rodrigo de Paula [UNESP]. "A atividade antimicrobiana de agentes desinfetantes incorporados ao gesso tipo IV". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/98032.
Testo completoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Vários protocolos de desinfecção podem ser usados para romper a cadeia de infecção cruzada entre o consultório odontológico e o laboratório de prótese. A inclusão de agentes antimicrobianos à composição do gesso ou a manipulação do gesso com soluções desinfetantes podem ser usados com esta finalidade. O propósito deste estudo foi avaliar a atividade antimicrobiana de dois agentes desinfetantes (digluconato de clorexidina 2% e cloridrato de clorexidina 98%) incorporados ao gesso IV (FujiRock - GC Europe, Leuven, Bélgica) durante sua manipulação. No teste microbiológico de difusão em Agar foram uti l izados os seguintes microorganismos: Escherichia coli, Staphylococcus aureus, Bacilus subtilis e Candida albicans. Amostras com 5 mm de diâmetro e 3 mm de espessura foram separadas em quatro grupos: 1) gesso manipulado com água destilada esterilizada (controle positivo); 2) discos de papel embebidos com solução de digluconato de clorexidina 2% (controle negativo); 3) gesso manipulado com solução de digluconato de clorexidina 2%; 4) gesso com a incorporação de cloridrato de clorexidina 98% em pó, na proporção de 1% da massa do gesso, e manipulado com água destilada esterilizada. Após 1 hora e 24 horas do vazamento do gesso, as amostras foram posicionadas em placas de Petri com meios de cul tura específicos inoculados com as suspensões microbianas. A atividade antimicrobiana dos desinfetantes foi avaliada pelo diâmetro médio dos halos de inibição do crescimento microbiano. Os valores foram analisados pela ANOVA Aninhada (p<0,05) e teste de Tukey para comparações específicas. Os resultados encontrados demonstraram que os agentes desinfetantes analisados apresentaram atividade antimicrobiana quando misturados ao gesso, com exceção para Candida albicans, na qual não houve efeito da solução de clorexidina nos dois períodos de análise...
Many protocols for disinfection procedures can be used to break the chain of cross-contamination between dental office and dental laboratory. The inclusion of antimicrobial agent to the composition of gypsum or the manipulat ion of gypsum with disinfectant substances can be used to that aim. The purpose of this study was to evaluate the antimicrobial activity of two disinfectant agents (2% chlorhexidine digluconate and 98% chlorhexidine hydrochloride) incorporated into type IV dental stone (FujiRock - GC Europe, Leuven, Belgium) at the time of mixing. The microbiological test used was the Agar diffusion test to the following microorganisms: Escherichia coli, Staphylococcus aureus, Bacilus subtilis and Candida albicans. Samples of 5 mm in diameter and 3 mm in length were separated in four groups: 1) dental stone mixed wi th steri le distilled water (positive control); 2) paper disk soaked wi th solution of 2% chlorhexidine digluconate (negative control); 3) dental stone mixed with solution of 2% chlorhexidine digluconate; 4) dental stone wi th incorporation of chlorhexidine hydrochloride 98% powder, in proportion of 1% of the dental stone mass, and mixed with sterile distilled water. The samples were placed, 1 hour and 24 hours after pouring of dental stone, in Petri plates with specific cul ture medium wich were inoculated with the microbial suspensions. The antimicrobial activity of disinfectant was evaluated by the average diameter of microbial growth inhibi tion zones. The data were analyzed with a Nested ANOVA (p<0,05) and Tukey test for specific comparisons. The disinfectant agents analyzed demonstrated antimicrobial effect against microorganisms used in this study, in exception to Candida albicans, against wich there was not effect from chlorhexidine digluconate at two periods of analysis. Significant difference between disinfectantes were found to all microrganisms... (Complete abstract click electronic access below)
Nagano, Yuriko. "Application of molecular techniques in medical microbiology". Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479415.
Testo completoJones, Frances Patricia. "The microbiology of lean and obese soil". Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/69408/.
Testo completoSilva, João Carlos Tenente da. "Huambo Microbiology Laboratory : economical and financial viability". Master's thesis, Instituto Superior de Economia e Gestão, 2016. http://hdl.handle.net/10400.5/11857.
Testo completoEste trabalho foi realizado no âmbito de um projeto para uma empresa sediada em Huambo, na qual foi pedido uma análise de viabilidade económica e financeira para a construção de um laboratório de microbiologia de alimentos. Esta será a primeira empresa localizada em Huambo, na qual irá testar a qualidade dos produtos importados e exportados em Angola. Numa primeira fase foi estudado o valor inicial para este investimento, a nível de infraestruturas e equipamentos. Para conseguir uma previsão deste investimento, foram analisados alguns laboratórios concorrentes em Portugal, apesar da difícil comparação em termos de dimensão e custos. Este será um investimento realizado exclusivamente através de financiamento bancário. A taxa de juro para este empréstimo foi calculada com base nas taxas de juro aplicadas em casos e valores de financiamento semelhantes. De seguida, foi elaborado uma projeção do volume de negócios baseado na informação recolhida relativamente às importações e exportações neste sector. Com esse volume de negócio, foram calculados todos os custos inerentes ao funcionamento da empresa, como por exemplo, custos fixos e variáveis e custos com salários. Os custos do investimento irão ser depreciados ao longo dos cinco anos previstos. Para melhorar a análise, foram realizados três cenários, de forma, a perceber o quanto poderá influenciar algumas alterações nas previsões. Para perceber a viabilidade económica e financeira deste projeto foi utilizado o método do desconto dos Cash-Flow. Com este método foi também possível obter a taxa interna de rentabilidade e o período no qual o investimento será pago.
This work was carried out for a project in a company based in Huambo, which was asked for an economic and financial viability study for the construction of a food microbiology laboratory. This will be the first company located in Huambo, which will test the quality of imported and exported products in Angola. In a first phase the initial value was studied for this investment, such as buildings, frame-work and equipment. To get the investment’s provision, some competitors’ laboratories were analyzed in Portugal, despite the difficult comparison in terms of size and cost. This will be an investment made exclusively through bank financing. The interest rate for this loan was calculated based on the interest rates applied in similar cases and financing values. Then a turnover projection based on information collected on imports and exports in this sector was prepared. With this turnover, they calculated all the costs of operation of the business, such as fixed and variable costs and wage costs. The investment costs will be depreciated over the five year period. To improve the analysis, there were three scenarios (pessimistic, average and optimistic), in order, to realize how much changes on quantity and costs can influence the forecasts. To realize the economic and financial viability of this project we used the discount method of Cash Flow. With this method it was also possible to obtain the internal rate of return and payback period.
Pitt, Sarah Jane. "Managing for quality in clinical microbiology services". Thesis, Liverpool John Moores University, 2001. http://researchonline.ljmu.ac.uk/5526/.
Testo completoYuan, Heyang. "Bioelectrochemical Systems: Microbiology, Catalysts, Processes and Applications". Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/79910.
Testo completoPh. D.
Липовська, Вікторія Вікторівна, Виктория Викторовна Липовская, Viktoriia Viktorivna Lypovska, Неля Георгіївна Горобченко, Неля Георгиевна Горобченко, Nelia Heorhiivna Horobchenko e D. M. Horobchenko. "Robert Koch - the father of clinical microbiology". Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/27500.
Testo completoDharod, Meghna. "Diabetic foot : microbiology, pathogenesis and glycan studies". Thesis, University of Westminster, 2010. https://westminsterresearch.westminster.ac.uk/item/9057z/diabetic-foot-microbiology-pathogenesis-and-glycan-studies.
Testo completoGuermonprez, Cyprien. "Droplet-based Microfluidic Platform for Quantitative Microbiology". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX106/document.
Testo completoDevelopment of a microfluidic chip for quantitative microbiology. The chip allow for parallel culture of thousands bacterial colonies in micro-droplets stored in static array. The 2D-array enable not only the visualisation of each colonies in timelapse experiment but also the extraction of any of them out of the chip at any time for further analysis (PCR, re-culture,...). The platform is adaptable to a concentration gradient producer, for which we present the physical understanding of working mechanism, that can apply different chemical environments to each colony. We developed in parallel a software that perform the analysis of the data generated by the platform to adress bacteria growth studies as well as the impact of antibiotics on bacteria proliferation
TESTI, DAVIDE. "Periodontal microbiology: new findings about oral microbiota". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2014. http://hdl.handle.net/2108/203046.
Testo completoGarcia, Mendez Karellen Beren. "Infection of human placental cells by Brucella". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT065.
Testo completoBrucella are intracellular bacteria responsible for brucellosis, a worldwide zoonotic disease associated with infectious abortions in animals, which causes huge economical losses in the livestock industry and long lasting health problems in humans. In contrast to animals, evidence of Brucella infections cause obstetric complications in humans is scarce. However, epidemiological studies have shown significant increases in the risk of adverse pregnancy outcomes (miscarriage, stillbirth, preterm delivery) in pregnant women infected with Brucella. Moreover, several zoonotic Brucella species were shown to infect efficiently human cytotrophoblasts (CTB) and extravillous trophoblasts (EVT), two types of cells with essential immune and hormonal functions during placental development. In the present study, we studied the effect of Brucella infection in human trophoblasts, from both the bacterial and the host sides. We evaluated the intracellular behavior of different Brucella strains, representing different species, hosts or associated symptoms. We found no correlation between the bacterial replication rate in trophoblasts and whether the strains were associated with pregnancy complications in their respective host. Importantly, we show that strains isolated from female baboons after stillbirth can infect human trophoblasts and affect some of their properties that are essential during placental development. We also started the characterization of atypical intracellular structures in which Brucella seem to be able to survive in certain types of trophoblasts. From the host side, we analyzed the role of the eukaryotic protein CD98hc in trophoblast infection. We found that CD98hc is important for infection of trophoblasts by Brucella, as shown previously in other cell types, and that infection affects the level of the protein in trophoblasts. Infection of human trophoblasts by Brucella could thus affect their function during placental development, leading to complications in pregnancy.The results obtained in this work contribute to a better understanding of the mechanisms that could lead to obstetric complications in Brucella infected pregnant women and provide important information for the clinical management of brucellosis during pregnancy
Jeronymo, Ana Beatriz de Oliveira [UNESP]. "Avaliação do potencial probiótico de bactérias acidoláticas produtoras de substância antimicrobiana isoladas de mussarela de búfala". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/94803.
Testo completoAs bactérias acidoláticas (BAL) constituem um grupo de micro-organismos heterogêneos Gram positivos, catalase negativos, anaeróbios facultativos e produtores de ácido lático . Estas bactérias têm despertado grande interesse na indústria de alimentos devido à produção de substâncias antimicrobianas, tais como as bacteriocinas. Estas substâncias têm a capacidade de reduzir a contaminação por patógenos e deteriorantes em alimentos, resultando em produtos com maior vida de prateleira. Outra característica importante presente em algumas linhagens de BAL é apresentar efeitos benéficos aos consumidores. O objetivo desse trabalho foi avaliar a produção de substâncias antimicrobianas por 38 cepas de BAL isoladas de mussarela de búfala, caracterizar as bacteriocinas quanto ao espectro de ação, estabilidade em diferentes pH, estabilidade térmica e resistência a agentes químicos. Para as cepas produtoras de bacteriocina também foi avaliado o efeito inibitório de L isteria monocytogenes ATCC 7644 em leite UHT integral e leite UHT desnat ado, e avaliar o potencial probiótico . Das trinta e oito cepas de BAL isoladas de mussarela de búfala, oito foram produtoras de substância antimicrobiana. Essas cepas foram identificadas como: Lactobacillus delbrueckii subsp. bulgaricus (cepa 13) , Lactobac illus casei ( cepa 24), L eu conostoc citreum (cepa 28 ) e Leuconostoc mesenteroides subsp. mesenteroides (cepas 26, 30 e 32). O estudo da natureza do composto confirmou que os compostos microbianos são bacteriocinas. As bacteriocinas produzidas pel as cepas 26 e 32 não foram afetadas pelo calor , extremos d e pH e diferentes detergentes. As cepas 26 e 32 reduziram a população do micro -organismo patogênico L. monocytogenes ATCC 7644 quando inoculadas em leite UHT integral e leite UHT desnatado, apresentando um efeito...
Lactic acid bacteria (LAB) ar e a heterogeneous group of Gram-positive microorganisms, catalase negative, facultative anaerobes and lactic acid producers. These bacteria have attracted great attention from the food industry due to the production of antimicrobial substances such as bacteriocins. These substances have the ability to reduce food spoilage and contamination by pathogens, resulting in products with longer shelf life. Another important feature present in some strains of LAB is to provide benefits to consumers. The aim of this study is to evaluate the production of antimicrobial substances by 38 LAB strains isolated from water-buffalo mozzarella cheese, and characterize the spectrum of activity of the bacteriocins, stability at different pH values, thermal stability and its resistance to chemicals. The bacteriocin-producing strains were also evaluated regarding the inhibitory effect on L. monocytogenes ATCC 7644 in UHT whole milk and UHT skim milk, and the probiotic properties. Six of the thirty-eight strains of LAB isolated from water-buffalo mozzarella cheese produce d antimicrobial substances. These strains were identified as L actobacillus delbrueckii subsp. bulgaricus (strain 13), Lactobacillus casei (strain 24), Leuconostoc citreum (strain 28) and Leuconostoc mesenteroides subsp. mesenteroides (strains 26, 30 and 32). The study of the nature of the antimicrobial compounds confirmed that they are bacteriocins. The bacter iocins produced by strains 26 and 32 were not affected by heat, extreme pH and different detergents. Strains 26 and 32 reduced the pathogenic microorganism Listeria monocytogenes ATCC 7644 population when inoculated in UHT whole and UHT skim milk, presenting a bacteriostatic effect. Strains 1 3, 24, 28 and 32 survived during the passage through the simulated gastrointestinal tract when inoculated... (Complete abstract click electronic access below)
Jeronymo, Ana Beatriz de Oliveira. "Avaliação do potencial probiótico de bactérias acidoláticas produtoras de substância antimicrobiana isoladas de mussarela de búfala /". São José do Rio Preto, 2013. http://hdl.handle.net/11449/94803.
Testo completoBanca: Svetoslav Dimitrov Todorov
Banca: Mara Corrêa Lelles Nogueira
Resumo: As bactérias acidoláticas (BAL) constituem um grupo de micro-organismos heterogêneos Gram positivos, catalase negativos, anaeróbios facultativos e produtores de ácido lático . Estas bactérias têm despertado grande interesse na indústria de alimentos devido à produção de substâncias antimicrobianas, tais como as bacteriocinas. Estas substâncias têm a capacidade de reduzir a contaminação por patógenos e deteriorantes em alimentos, resultando em produtos com maior vida de prateleira. Outra característica importante presente em algumas linhagens de BAL é apresentar efeitos benéficos aos consumidores. O objetivo desse trabalho foi avaliar a produção de substâncias antimicrobianas por 38 cepas de BAL isoladas de mussarela de búfala, caracterizar as bacteriocinas quanto ao espectro de ação, estabilidade em diferentes pH, estabilidade térmica e resistência a agentes químicos. Para as cepas produtoras de bacteriocina também foi avaliado o efeito inibitório de L isteria monocytogenes ATCC 7644 em leite UHT integral e leite UHT desnat ado, e avaliar o potencial probiótico . Das trinta e oito cepas de BAL isoladas de mussarela de búfala, oito foram produtoras de substância antimicrobiana. Essas cepas foram identificadas como: Lactobacillus delbrueckii subsp. bulgaricus (cepa 13) , Lactobac illus casei ( cepa 24), L eu conostoc citreum (cepa 28 ) e Leuconostoc mesenteroides subsp. mesenteroides (cepas 26, 30 e 32). O estudo da natureza do composto confirmou que os compostos microbianos são bacteriocinas. As bacteriocinas produzidas pel as cepas 26 e 32 não foram afetadas pelo calor , extremos d e pH e diferentes detergentes. As cepas 26 e 32 reduziram a população do micro -organismo patogênico L. monocytogenes ATCC 7644 quando inoculadas em leite UHT integral e leite UHT desnatado, apresentando um efeito... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Lactic acid bacteria (LAB) ar e a heterogeneous group of Gram-positive microorganisms, catalase negative, facultative anaerobes and lactic acid producers. These bacteria have attracted great attention from the food industry due to the production of antimicrobial substances such as bacteriocins. These substances have the ability to reduce food spoilage and contamination by pathogens, resulting in products with longer shelf life. Another important feature present in some strains of LAB is to provide benefits to consumers. The aim of this study is to evaluate the production of antimicrobial substances by 38 LAB strains isolated from water-buffalo mozzarella cheese, and characterize the spectrum of activity of the bacteriocins, stability at different pH values, thermal stability and its resistance to chemicals. The bacteriocin-producing strains were also evaluated regarding the inhibitory effect on L. monocytogenes ATCC 7644 in UHT whole milk and UHT skim milk, and the probiotic properties. Six of the thirty-eight strains of LAB isolated from water-buffalo mozzarella cheese produce d antimicrobial substances. These strains were identified as L actobacillus delbrueckii subsp. bulgaricus (strain 13), Lactobacillus casei (strain 24), Leuconostoc citreum (strain 28) and Leuconostoc mesenteroides subsp. mesenteroides (strains 26, 30 and 32). The study of the nature of the antimicrobial compounds confirmed that they are bacteriocins. The bacter iocins produced by strains 26 and 32 were not affected by heat, extreme pH and different detergents. Strains 26 and 32 reduced the pathogenic microorganism Listeria monocytogenes ATCC 7644 population when inoculated in UHT whole and UHT skim milk, presenting a bacteriostatic effect. Strains 1 3, 24, 28 and 32 survived during the passage through the simulated gastrointestinal tract when inoculated... (Complete abstract click electronic access below)
Mestre
Paradela, Gomes Cláudia Sofia. "Antimicrobial resistance and new insights in the diagnosis of Carrión's Disease". Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/401758.
Testo completoLa enfermedad de Carrión es una enfermedad desatendida restringida a las zonas más pobres de la región Andina. Uno de los problemas es la falta de programas de tratamiento eficaces bien definidos. Por otro lado, y quizás sea la necesidad más imperiosa, es preciso tener una manera fácil de realizar el diagnóstico. Nuevos estudios inmunológicos ayudarán a identificar nuevas moléculas con potencial diagnóstico. Los resultados de esta tesis han sido separados en 2 aspectos diferentes de la enfermedad de Carrión; la resistencia a los antimicrobianos (Capítulo I) y el diagnóstico y caracterización de muestras clínicas (Capítulo II). El capítulo I describe un estudio sobre los mecanismos de resistencia desarrollados en presencia de los 4 antibióticos más comunmente utilizados en el tratamiento de la enfermedad de Carrión, evidenciándose la capacidad de Bartonella bacilliformis de volverse resistente a estos antibióticos, tanto por el desarrollo de alteraciones en sus dianas, como por la sobreexpresión de bombas de expulsión. El capítulo 2 analiza aspectos del diagnostico de la enfermedad de Carrión que se abordan en 3 estudios. En el primero se caracterizan molecularmente muestras obtenidas de pacientes de un supuesto brote de fiebre de Oroya. Sin embargo, proponemos que este brote se atribuyó erróneamente a B. bacilliformis sugieriéndose que el agente causante fue Sphingomonas faeni. En el segundo hemos evaluado el límite de detección de varios esquemas de PCR para detectar B. bacilliformis. Parece que la sensibilidad de estas técnicas podría permitir el diagnóstico de casos agudos de la enfermedad de Carrión, pero su aplicabilidad para detectar a los portadores sanos o con una baja bacteriemia sigue sin estar clara. Por fin, en el tercer estudio de este capítulo el objetivo fue la identificación y caracterización de candidatos inmunogénicos de B. bacilliformis que puedan en un futuro ser utilizados en una herramienta de diagnostico rápida. Se identificaron 4 proteínas inmunogénicas: Pap31, GroEL, SCS-α y SCS-β. El diseño de esquemas de tratamiento que minimicen la selección de resistencia junto con el desarrollo de técnicas de diagnóstico que puedan ser implementadas en zonas rurales es esencial para el control y eliminación de la enfermedad de Carrión.
Planell, Mas Elena de. "Verrugas plantares: caracterización de los virus causales y aplicación del láser 1064 nm a su tratamiento". Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/402516.
Testo completoINTRODUCTION: Plantar warts, caused by human papillomaviruses (HPVs), are benign cutaneous tumors. In this study, we aimed to identify the HPV genotypes of plantar warts and explore their relation to demographic and clinical characteristics of patients. We also evaluated the efficacy of 1064 nm laser in the treatment of plantar warts as well as the number of laser sessions and discomfort experienced by patients. MATERIAL AND METHODS: A total of 72 patients diagnosed with plantar warts were recruited at the Laser unit at Podiatric Hospital, University of Barcelona, Spain. Laminar sections of warts were collected, DNA of samples was extracted and HPV types were identified. To assess the effectiveness of the laser treatment, operating mode parameters such as pulse duration, pause, power and fluence were optimized. RESULTS: The most prevalent genotypes detected among the 105 analyzed plantar warts were HPV-57 (37.1%), HPV-27 (23.8%), HPV-1a (20.9%), HPV-2 (15.2%) and HPV-65 (2.8%). The majority of patients (78%) presented one single plantar wart, whereas multiple warts were detected in 22.2% of patients. One patient with multiple warts presented HPV types from two different genera, suggesting the spread of warts by self-inoculation as well as by de novo infection. No significant differences between the number of warts in toes, midfoot and heel were found. The most prevalent HPV types detected in all areas belonged to the alpha genus. Laser treatment was applied using optimized parameters: 26.7% of warts with a diameter ≤4 mm required only one laser session for removal, 26.7% needed two sessions, 40.0% required 3 laser sessions and 6.7% four sessions; 11.5% of warts with a diameter >4 mm required only one laser session for removal, 23.1% required two sessions, 23.1% required three sessions and 19.2% five sessions. CONCLUSIONS: This work provides new insight on plantar warts and their associated HPV genotypes, and evidences the usefulness and reliability of both the sample collection procedure and the PCR method used for HPV detection and typing. The parameters used with 1064nm laser show a safe and effective treatment for plantar warts. The average number of treatments was 2-3 sessions, causing minimal discomfort to patients.
Abreu, Catherine Simões de. "Áreas limpas: estudo de correlação entre partículas viáveis e não viáveis". Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-14062016-181645/.
Testo completoThis paper represents a study about environmental monitoring data for cleanrooms. The parameters that were compared are: total airborne particles of 0.,5 and 5.0 µm, airbome colony forming units (CFU\'s) and CFU\'s on surfaees (Rodac®). Most attention was paid to areas where critical handling is performed (class A areas). In these areas sampling was performed \"at rest\" and \"dynamic\" conditions, before and after sanitization and during certification and routine steps. These data indicates that the parameters are not particularly dependent upon the lay out or classification of areas, but rather on the use of the areas, and how the operators behave in them. Evaluating the data, the conclusion was about a correlation among different sampling places, for total airborne particles of 0.,5 and 5.0 µm, and absence of this kind of correlation in laminar flows positions. Also, correlation values were always increasing with the cleanless of the environment. The microorganisms most frequently isolated in areas A2, A3 and A4 were Bacillus sp, Staphylococcus sp and Corynebacterium sp.
Ciesielski, Francisco Isaak Nícolas [UNESP]. "Microrganismos oportunistas e exógenos na microbiota bucal de pacientes oncológicos submetidos à radioterapia de cabeça e pescoço". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/91426.
Testo completoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O objetivo deste estudo foi avaliar a ocorrência de microrganismos exógenos e oportunistas (bactérias entéricas, pseudomonados, leveduras e Helicobacter pylori) na cavidade bucal de pacientes submetidos à radioterapia para tratamento de câncer de cabeça e pescoço. Cincoenta pacientes que iria receber radioterapia foram examinados antes, durante e 30 dias após radioterapia. Amostras de saliva, mucosa e biofilme foram coletadas e os microrganismos foram detectados por cultura e Reação em Cadeia da Polimerase (PCR). Candida albicans, C. tropicalis, C. krusei, C. glabrata e C. parapsilosis foram as leveduras mais prevalentes nos pacientes submetidos a radioterapia. Gêneros Citrobacter, Enterobacter, Enterococcus, Klebsiella, Proteus, e Pseudomonas forma as bactérias mais frequentemente cultivadas. As bactérias alvo foram cultivadas de 77.8% dos pacientes edêntulos e 46.9% dos pacientes dentados 30 dias após a radioterapia. Por PCR, estes microrganismos foram detectados em todos os pacientes edêntulos e 78.1% dos pacientes dentados. Bactérias não orais e espécies de Cândida foram mais prevalentes nestes pacientes. Modificações no meio ambiente oral devido a radioterapia parecem facilitar a colonização por estes microrganismos.
The aim of this study was to evaluate the occurrence of opportunistic and exogenous microrganisms (enteric bacteria, pseudomonads, yeasts and Helicobacter pylori) in the oral cavity of patients undergoing radiotherapy (RT) for treatment of head and neck cancer. Fifty patients receiving RT were examined before, during and 30 days after RT. Saliva, mucosa, and biofilm samples were collected and microorganisms were detected by culture and Polymerase Chain Reaction (PCR). Candida albicans, C. tropicalis, C. krusei, C. glabrata and C. parapsilosis were the most prevalent yeasts in patients submitted to RT. Genera Citrobacter, Enterobacter, Enterococcus, Klebsiella, Proteus, and Pseudomonas were the most frequently cultivated bacteria. Targeted bacteria were cultivated from 77.8% edentulous and 46.9% dentate patients 30 days after RT. By PCR, these microorganisms were detected from all edentulous patients and from 78.1% of dentate patients. Non-oral bacteria and Candida species were prevalent in these patients. Modifications of the oral environment due to RT seem to facilitate the colonization of these microorganisms.
Vieira, Narciso Almeida [UNESP]. "Microbiota intestinal de crianças com anomalias craniofaciais atendidas em um hospital especializado". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/101491.
Testo completoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O ecossistema gastrintestinal é caracterizado por interações recíprocas e dinâmicas entre o epitélio gastrintestinal, células do sistema imunológico e sua microbiota intestinal (MI), a qual desempenha atividades metabólicas importantes locais (mucosa intestinal) e sistêmicas. Avaliar a MI de crianças com malformação craniofacial atendidas em um hospital especializado e verificar a influência da antibioticoprofilaxia com cefazolina em palatoplastia foi o objetivo desse trabalho. Foram isoladas e quantificadas as bactérias anaeróbias intestinais dos gêneros Bacteroides sp, Bifidobacterium sp e Lactobacillus sp nas fezes de 11 crianças sem fissura de palato (C) e de 50, com fissura de palato (FP), no período compreendido entre maio de 2007 a setembro de 2008. Foi avaliada a MI de 18 crianças com fissura de palato após 24 horas de tratamento, em dose única na indução anestésica, com cefazolina para palatoplastia. Observou-se que a frequência de Bacteroides sp foi maior no grupo FP (p < 0,001). Para Lactobacillus sp, houve tendência a maior quantidade (p = 0,086) no grupo FP. Não houve diferença na frequência de Bifidobacterium sp entre os dois grupos de crianças (p = 0,495). Houve diminuição do número de UFCs de Bacteróides sp (p = 0,031) e Lactobacillus sp (p = 0,004) em crianças com fissura tratadas com cefazolina em cirurgia de palato. Para o gênero Bifidobacterium sp, houve tendência à diminuição nas UFCs (p = 0,063). A dificuldade de ingestão de nutrientes, aleitamento materno insuficiente, otites recorrentes, entre outras ocorrem com frequência em indivíduos com malformação craniofacial, o que pode ter influenciado na composição da MI. A associação da palatoplastia e o uso de antibiótico...
The gastrointestinal ecossystem is characterized by reciprocal and dynamic interactions between the host and the intestinal microbiota (IM), which performs local important metabolic (intestinal mucosa) and systemic activities. The purposes of this study are the assessment of the IM in children with craniofacial malformation attended at a specialized hospital and the verification of the influence of the antibiotic prophylaxis with cefazolin on palatoplasty. The intestinal anaerobic bacteria Bacteroides sp, Bifidobacterium sp and Lactobacillus sp were isolated and quantified in the feces of 11 non-cleft children (NC) and 50 cleft children (CP), from May 2007 to September 2008. After a 24-hour treatment, the IM in 18 cleft children was evaluated – in a single dose – by means of anesthetic induction with cefazolin, in palatoplasty. It was observed that the Bacteroides sp occurred more often in the CP group (p < 0.001). Regarding the Lactobacillus sp, the largest quantity (p = 0.086) tended towards the CP group. There was no frequency difference for the Bifidobacterium sp between the two groups of children (p = 0.495). There was a reduction in the number of Colony-Forming Units (CFUs) for the Bacteroides sp (p = 0.031) and the Lactobacillus sp (p = 0.004) in cleft children treated with cefazolin, in palate surgeries. Regarding the Bifidobacterium sp, there was a reduction tendency in the CFUs (p = 0.063). The difficulty to ingest nutrients, the insufficient breastfeeding, the recurrent otitis – among other things – are frequent in individuals with craniofacial malformation, which may have influenced the IM composition. The association between palatoplasty and the use of antibiotics has intensified the IM changes. New investigations must be performed in order to verify which factors related to the craniofacial malformation, the surgical treatment and the use of antimicrobians would... (Complete abstract click electronic access below)
Sanches, Raisa Déli de Oliveira. "Purificação e caracterização bioquímica da CGTase produzida por Paenibacillus campinasensis H69-3 /". São José do Rio Preto, 2018. http://hdl.handle.net/11449/180437.
Testo completoBanca: Gustavo Orlando Bonilla Rodriguez
Banca: Renato Grillo
Banca: Andréia Aparecida Jacomassi Carneiro
Banca: Hamilton Cabral
Resumo: Uma ciclomaltodextrina glucanotransferase (E.C. 2.4.1.19, CGTase) produzida pelo microrganismo Paenibacillus campinasensis linhagem H69-3, foi obtida por fermentação submersa a 45 °C, e a CGTase purificada por cromatografia de afinidade bioespecífica em resina Sepharose 6B ativada com β-CD. A enzima foi purificada até 23 vezes, obtendo um rendimento de 11,0%, e a atividade específica de 32,6 U mg-1 ao final da etapa de purificação. A massa molecular da enzima purificada foi estimada em 72 kDa por eletroforese desnaturante em gel de poliacrilamida na presença de dodecil-sulfato de sódio. O pH ótimo para a atividade enzimática foi de 6,5 e a enzima foi estável na faixa de pH de 6,5 a 8,0. A temperatura ótima foi de 65 °C em pH 6,5, e foi térmicamente estável até 55 °C na ausência de substrato durante 1 h de incubação e estável até 65 °C na presença de Ca2+ 5 mmol L-1. A atividade enzimática aumentou na presença de Ba2+, Mg2+, Ca2+, Ni2+, K+, Zn2+ e foi inibida na presenca dos íons metálicos Cu2+, Hg2+, Ag+, Li2+, Al3+ e NH42+ e por β‑, γ‑CD, DMSO, Triton, SDS e NaN3. Utilizando maltodextrina como substrato a CGTase apresentou 11,0±0,5 µmol min·mg e 0,30 ± 0,07 mg mL‑1, Vmáx e Km, respectivamente. Avaliaram-se os parâmetros termodinâmicos da CGTase, que demonstrou mais de 11 horas a 65 ºC como tempo de meia vida, e elevada resistência estrutural à desnaturação térmica quando avaliados os resultados de entropia, energia de ativação e entalpia
Abstract: A cyclomaltodextrin glucanotransferase (E.C. 2.4.1.19, CGTase) produced by 4 microorganism Paenibacillus campinasensis strain H69-3 was obtained by submerged fermentation at 45 °C and CGTase purified by biospecific affinity chromatography on β-CD activated Sepharose 6B resin. The enzyme was purified up to 23 times, yielding 11.0% yield, and the specific activity of 32.6 U mg-1 at the end of the purification step. The molecular weight of the purified enzyme was estimated at 72 kDa by denaturing polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The optimum pH for the enzymatic activity was 6.5 and the enzyme was stable in the pH range of 6.5 to 8.0. The optimum temperature was 65 °C at pH 6.5 and was thermally stable at 55 °C in the absence of substrate for 1 h incubation and stable at 65 ° C in the presence of Ca2+ 5 mmol L -1. The enzyme activity increased in the presence of Ba2+, Mg2+, Ca2+, Ni2+, K+, Zn2+ and was inhibited in the presence of Cu2+, Hg2+, Ag+, Li2+, Al3+ and NH42+ ions and by β, γ -CD, DMSO, Triton, SDS and NaN3. Using maltodextrin as substrate CGTase presented 11.0 ± 0.5 μmol min · mg and 0.30 ± 0.07 mg mL-1, Vmax and Km, respectively. The thermodynamic parameters of CGTase, which demonstrated more than 11 hours at 65 ºC as a half-life, and high structural resistance to thermal denaturation were evaluated when the results of entropy, activation energy and enthalpy were evaluated
Doutor
Massarente, Vanessa Salto. "Caracterização bioquímica e purificação das endoglucanases produzidas por Myceliophthora thermophila M.7.7 em cultivo em estado sólido /". São José do Rio Preto, 2018. http://hdl.handle.net/11449/154468.
Testo completoCoorientador: Eleni Gomes
Banca: Vanildo Luiz Del Bianchi
Banca: Luciano Takeshi Kishi
Resumo: As celulases são enzimas empregadas principalmente na indústria de papel e celulose e têxtil, e têm ganhado destaque pelo seu potencial hidrolítico em materiais lignocelulósicos na produção de etanol, já que são capazes de hidrolisar a celulose. O objetivo do projeto foi efetuar a caracterização e isolamento das endoglucanases produzidas pelo fungo termofílico Myceliophthora thermophila M.7.7 em cultivo em estado sólido. Foram realizados ensaios para avaliar os efeitos do pH, da temperatura, de diversas substâncias químicas, cátions e compostos fenólicos na atividade enzimática. A estimativa da massa molecular foi realizada por eletroforese em gel de poliacrilamida (SDS-PAGE), e como resultado foi possível observar sete endoglucanases detectadas por zimografia, que possuem massa molecular estimada entre 26 e 82 kDa. O valor ótimo para o pH do extrato enzimático bruto foi 5,5 e 70ºC para a temperatura ótima em incubação de 4 minutos. Em relação à estabilidade do extrato bruto, os maiores valores ocorreram entre as faixas de pH de 6 a 6,5, e 30 e 40ºC para temperatura até 120 minutos. Entre os reagentes testados, Triton, DTT e Isopropanol aumentaram a atividade enzimática sobre o extrato bruto em cerca de 10%. Os cátions NaCl, SrCl2, BaCl2 e ZnCl2 aumentaram a atividade das endoglucanases. Em relação aos compostos fenólicos, todos induziram em diversos graus o decréscimo da atividade das endoglucanases do extrato bruto. Das sete endoglucanases, três foram isoladas pela extração...
Abstract: Cellulases are enzymes used mainly in the paper and cellulose and textile industries and have been highlighted for their hydrolytic potential in lignocellulosic materials in the production of ethanol, since they are capable of hydrolyzing cellulose. The objective of the project was to characterize and isolate the endoglucanases produced by the thermophilic fungus Myceliophthora thermophila M.7.7 in solid state cultivation. Tests were carried out to evaluate the effects of pH, temperature, several chemical substances, cations and phenolic compounds on enzymatic activity. The molecular weight estimation was performed by polyacrylamide gel electrophoresis (SDS-PAGE), and as a result it was possible to observe seven endoglucanases detected by zymography, which have an estimated molecular mass between 26 and 82 kDa. The optimum pH for the crude enzyme extract was 5.5, and 70 °C for the optimum incubation temperature for 4 minutes. Regarding the stability of the crude extract, the highest values occurred between the pH ranges from 6 to 6.5, and 30 to 40ºC for temperature up to 120 minutes. Among the tested reagents, Triton, DTT and Isopropanol increased the enzymatic activity on the crude extract by about 10%. NaCl, SrCl2, BaCl2 and ZnCl2 increased the endoglucanase activity. With respect to the phenolic compounds, all induced to varying degrees the decrease in the activity of the endoglucanases of the crude extract. Of the seven endoglucanases, three were isolated by direct gel ...
Mestre
Rodrigues, Daniele Masselli 1972. "Infecção por Cardiovirus (virus da encefalomielite murina de Theiler - TMEV) em colonias convencionais de ratos". [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317119.
Testo completoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-03T22:33:53Z (GMT). No. of bitstreams: 1 Rodrigues_DanieleMasselli_M.pdf: 1852380 bytes, checksum: f83cb847eec2bcf31bf414b3bbf154ba (MD5) Previous issue date: 2004
Resumo: O vírus da encefalomielite murina de Theiler (TMEV) é um patógeno entérico de camundongos, pertencente ao gênero Cardiovirus da família Picornaviridae. O TMEV é um vírus não envelopado, icosaédrico, com 20 - 30 nm e genoma constituído de RNA fita simples com polaridade positiva. Os TMEV têm sido classificados em dois subgrupos, de acordo com sua atividade biológica após inoculação intracerebral. Cepas neurovirulentas (GDVII e FA) induzem uma encefalite aguda e fatal, enquanto aquelas de baixa virulência (TO, WW, DA e BeAn) persistem no sistema nervoso central, induzindo doença crônica, caracterizada por desmielinização. A infecção natural por TMEV tem sido demonstrada em colônias onvencionais de camundongos e, em sua maioria, a infecção é assintomática. Embora o TMEV seja descrito como um patógeno de camundongos, anticorpos para TMEV-GDVII têm sido detectados em soros de ratos provenientes de biotérios que mantêm colônias convencionais. A prevalência da infecção por TMEV-GDVII nestas colônias de ratos é alta, em torno de 54,6%. Assim, este trabalho teve por finalidade demonstrar, por métodos sorológicos e molecular, a infecção natural por TMEV em colônias de ratos. Soros destes animais foram analisados pela reação de imunofluorescência indireta e a presença de anticorpos anti-TMEV-GDVII foi detectada em 86,3% deles. Ao mesmo tempo, pelo teste de soroneutralização, 77,2% destes soros demonstraram anticorpos neutralizantes para TMEV-GDVII. Com o objetivo de isolar o vírus de ratos, sistemas ¿in vitro¿ e ¿in vivo¿ foram utilizados. Nove passagens sucessivas de amostras de suspensão intestinal foram feitas em células BHK-21 e não foi possível demonstrar efeito citopático. Sinais clínicos da infecção por TMEV em camundongos, ou seja, paralisia das patas posteriores e tremores, foram demonstrados em camundongos e ratos neonatos inoculados com suspensão intestinal de ratos soropositivos e com a cepa padrão de TMEV-GDVII. Os resultados da RT-PCR demonstraram a presença de RNA viral em amostras de cérebro de ratos inoculados com a suspensão intestinal, com TMEV-GDVII e nas amostras de fezes de ratos provenientes de diferentes biotérios convencionais. Os resultados demonstram que ratos se infectam naturalmente por TMEV e, embora hajam poucas descrições na literatura da interferência deste vírus em pesquisas biomédicas, a monitoração sanitária para TMEV em biotérios que mantêm colônias de ratos deve ser incluída
Abstract: Theiler¿s murine encephalomyelitis virus (TMEV) is an enteric pathogen of mice and belongs to the Cardiovirus genus in the family Picornaviridae. TMEV is a non-enveloped, icosaedric virus with 20 ¿ 30 nm size and it has an RNAss positive sense genome. TMEV has been divided in two subgroups on the basis of their biological activities after intracerebral inoculation. Neurovirulent strains (GDVII and FA) causes an acute and fatal encephalitis in mice and in contrast, low neurovirulent strains (DA, BeAn 8386, WW and TO) causes a persistent infection in the central nervous system and produce a chronic disease characterized by demyelination. TMEV infection with low neurovirulent strains has been used as an experimental model to help the studies on demyelination process induced by virus infection and to study diseases as Multiple Sclerosis. The natural infection by TMEV has been related in conventional colonies of mice and it¿s frequently asymptomatic. Although TMEV has been described as a pathogen of mice, antibodies against TMEV-GDVII has been detected in serum of rats reared in non-barrier colonies. Facing this, the purpose of the present study was to demonstrate the natural infection of TMEV in rat colonies through serological and molecular methods (RT-PCR). The rat serum were analysed by indirect immunofluorescence assay and antibodies against TMEV-GDVII were detected in 86,3% of the serum analysed. In the neutralization assay, 77,2% of the same serum showed neutralizing antibodies anti TMEVGDVII. To further isolate this rat virus, ¿in vitro¿ and ¿in vivo¿ systems were used. Nine blinded passages of the intestinal suspension were realized in BHK-21 cells, but no citopathic effect was identified. Clinical signs of TMEV infection in mice were characterized by flaccid paralisis of hind legs and tremor when newborn rats and mice were inoculated with intestinal suspension of seropositive rats and with the prototype strain of TMEV-GDVII. The RT-PCR results showed the RNA genome in the brain samples of rats and mice inoculated both with the intestinal suspension and the prototype strain. In the fecal samples, the RNA genome was also detected. In summary, rats can be naturally infected by TMEV and although there are a few examples in the literature of TMEV infection interference with biomedical researches, a health monitoring program for TMEV should be included in the rat colonies
Mestrado
Microbiologia
Genetica e Biologia Molecular