Dissertationen zum Thema „Biofilm cultures“
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Behnke, Sabrina. „Disinfection susceptibilities of detached biofilm clusters compared to planktonic cells and biofilms in single species and dual species cultures“. Diss., Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/behnke/BehnkeS0811.pdf.
Der volle Inhalt der Quelleau, L. Hughes@murdoch edu, und Leonie Hughes. „Multistage and multiple biomass approaches to efficient biological nitrogen removal using biofilm cultures“. Murdoch University, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20080523.134154.
Der volle Inhalt der QuelleHughes, Leonie. „Multistage and multiple biomass approaches to efficient biological nitrogen removal using biofilm cultures“. Hughes, Leonie (2008) Multistage and multiple biomass approaches to efficient biological nitrogen removal using biofilm cultures. PhD thesis, Murdoch University, 2008. http://researchrepository.murdoch.edu.au/674/.
Der volle Inhalt der QuelleGillmann, Antoine. „Étude de la survie de contaminants bactériens modèles d’origine industrielle, isolés d’environnements oligotrophes, et élaboration de milieux synthétiques permettant leur croissance“. Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAJ004/document.
Der volle Inhalt der QuelleThe development of culture media to quickly and reproducibly detect fastidious microorganisms represents a significant change in the control of industrial products and processes.Two synthetic culture media have been developed to reach specifications. The development was performed by combining the analysis of nutritional compounds to the study of specific bacterial metabolisms. The formulations of the resulting culture media allow the growth of microorganisms with different nutritional requirements as those frequently isolated in industrial water.In parallel experiments on multi-species biofilms, using bacteria isolated from industrial water systems, it was observed that the survival of bacteria in nutrient-poor environments is dependent on cooperative interactions, based on "swarming" and "hitchhiking"
Pierra, Mélanie. „Couplage de la fermentation sombre et de l’électrolyse microbienne pour la production d’hydrogène : formation et maintenance du biofilm électro-actif“. Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20150/document.
Der volle Inhalt der QuelleNowadays, alternative and sustainable solutions are proposed to avoid the use of fossil fuel. Hydrogen, which constitutes a promising energy vector, is essentially produced by fossil fuel reforming (95%). Environmentally friendly production systems have to be studied. Two main families of technologies are explored to produce hydrogen: 1) by thermochemical and electrochemical decomposition of water and 2) from different biomass sources. Among those last ones, microbial electrolysis cells (MEC) allow to produce hydrogen by electrolysis of organic matter. A MEC consists in a classical cathode, which provides hydrogen production by electrochemical reduction of water, associated to a bio-anode that oxidizes organic substrates into carbon dioxide. This process is only possible because of the anodic development of an electroactive microbial biofilm which constitutes an electrocatalyst. In comparison to classical water electrolysis process, a MEC requires 5 to 10 times less electrical energy and therefore reduces the energetic cost of produced hydrogen. Furthermore, classical process of dark fermentation in mixed cultures converts sugars (saccharose, glucose) to hydrogen with a limited yield of 2-3 moles of hydrogen per mole of hexose because of the coproduction of organic acids (mainly acetic and butyric acids). Fed with acetate, a MEC can produce up-to 3 moles of hydrogen per mole of acetate. Therefore, the association of these two processes could permit to produce 8 to 9 moles of hydrogen per mole of hexose, which represents a major step toward the theoretical limit of 12 moles of hydrogen per mole of hexose.Therefore, this work aims at analyzing the relationship between microbial community structures and compositions and the associated macroscopic functions (biofilm electroactive properties, hydrogen production potential) in electroactive biofilms and in dark fermentation in conditions allowing the coupling of the two processes. The originality of this study is to work in saline conditions (30-35 gNaCl/L), which favors the charges transfer in the MEC electrolyte.First of all, feasibility of dark fermentation in saline conditions (3-75 gNaCl/L) has been shown. This was linked to an inhibition of produced hydrogen consumption and the predominance of a new Vibrionaceae species at salt concentrations higher than 58 gNaCl/L. Secondly, electroactive biofilm growth in conditions compatibles to dark fermentation (pH 5.5-7 and fed with different organic acids) allowed to select dominant microbial species in anodic biofilms that present promising electroactive properties (Geoalkalibacter subterraneus and Desulfuromonas acetoxidans) with maximum current densities up to 8.5 A/m². In parallel, the microbial selection occurring during iron-reducing enrichment method used to select species from a natural inoculum source and based on their capacity to transfer electrons to iron oxydes (Fe(III)) has been studied. A decrease of electroactive performances of the biofilm linked to the divergence of microbial selection led to a limitation of the number of iron-enrichment steps. However, enrichment on Fe(III) presents an efficient alternative to pre-select electroactive species with an increase of coulombic efficiency from 30±4% to 99±8% in comparison with a biofilm obtained with a non-acclimated inoculum. Finally, the addition of exogenous bacteria from a dark fermenter on the electroactive biofilm revealed a decrease of electroactivity with a decrease of maximum current density produced. This diminution could be explained by a lower substrate transfer due to an apparent thickening of the biofilm. Nevertheless, the stability of microbial composition and of bacterial quantity on the anode suggests that a production of exopolymers (EPS) occurred
Phoeurng, Sackona. „Mise en évidence de Listeria spp. Dans le contexte alimentaire au Cambodge et étude du comportement de L. Monocytogenes en biofilm sous l'influence de Pseudomonas fluorescens et de désinfectants“. Dijon, 2002. http://www.theses.fr/2002DIJOS054.
Der volle Inhalt der QuelleDastidar, Aniruddha. „ARSENITE OXIDATION BY PURE CULTURES OF THIOMONAS ARSENIVORANS STRAIN B6 IN BIOREACTOR SYSTEMS“. UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/70.
Der volle Inhalt der QuelleBorrel, Valérie. „Influence du microenvironnement sur la virulence et la formation de biofilm de Cutibacterium acnes“. Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR035/document.
Der volle Inhalt der QuelleAcne vulgaris is one of the most common skin diseases. Its pathogenesis is still unclear but Cutibacterium acnes (former Propionibacterium acnes) is considered as essential for its development. This bacterium is characterized by high genomic variability and some strains as ribotype 4 and 5 (RT4 and RT5) strains are highly associated with acne whereas RT6 strains are enriched in healthy skin. The physiological differences between these C. acnes types were evaluated dependently of their environment (culture media). Moreover, a link between acne and stress has been described, the use of preservative-free-cosmetics is burgeoning and bacteria can react to local factors by important metabolic changes. In this respect, two catecholamines and two cosmetic compounds were also tested. This study shows that the different C. acnes types are adapted to different ecological niches: acneic strains are adapted to sebaceous glands whereas non-acneic strains are more adapted to the skin surface and the upper hair follicle. Moreover, the acneic type seems associated to a more important inflammatory potential, which consolidates its possible implication in acne. The catecholamines can stimulate its biofilm formation and C. acnes treated by these molecules can stimulated the lipogenesis in sébocytes. Then, this study highlights the existence of a link between stress and the potential role of C. acnes in acne. Elsewhere, this study shows that the biofilm of C. acnes can be inhibited by Uriage thermal water and/or a rhamnose-rich polysaccharide (PS291®)
Goudot, Sébastien. „Étude des facteurs d'influence de l'écologie de Naegleria fowleri dans les biofilms“. Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0304/document.
Der volle Inhalt der QuelleThis study is aiming at preventing and reducing the proliferation of the pathogenic free-living amoeba Naegleria fowleri in several power plant cooling circuits. This work contributes to provide a better understanding of the ecology of this amoeba in complex environments such as freshwater biofilms, which recently has been recognized as privileged ecological niche for free-living amoebae. Laboratory tests were conducted to determine the impact of environmental factors such as temperature, type of support material for the biofilm formation, nutritional resources and monochloramination treatment on the behavior and the fate of Naegleria fowleri in the biofilm. This work has demonstrated that the survival, implantation, maintain, growth and decline of Naegleria fowleri in biofilms are mainly governed by a combination of the temperature and nutritional resource factors. The other factors: type of support material, monochloramination treatment, and amoebic competition, appeared rather as disruptive or inhibitory parameters of this dynamic. Moreover, the obtained results for the amoebic colonization of the biofilm matrix confirm the crucial role of this habitat as natural reservoir for free-living amoebae and Naegleria fowleri
Pandin, Caroline. „Exploration des mécanismes impliqués dans la bioprotection d'Agaricus bisporus par les biofilms de Bacillus subtilis QST713“. Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLA025/document.
Der volle Inhalt der QuelleWorldwide, food losses amount for about one-third of food for human consumption, 1.3 billion tons per year (FAO). A large fraction of these losses are due to microbiological alterations. The use of phytosanitary products remains today the most widely used solution in agriculture to limit these losses. However, with the EcoPhyto 2 plan, the French government aims to reduce the use of chemical pesticides by 50% by 2025, in particular by promoting the emergence of biocontrol. To develop this approach, it is necessary to understand the underlying mechanisms. The different modes of action of biocontrol by the microorganisms described are the stimulation of the natural defenses of the plants, the production of antimicrobial substances and the nutritional competition. The originality of this project is to integrate the biofilm mode of life into bioprotection mechanisms (spatial and nutritional competition, release of antimicrobial principles). In the French sector of the button mushrooms (Agaricus bisporus) culture, the biocontrol agent used since 2008 by more than 80% of the sector, is Bacillus subtilis QST713. This biofungicide shows a clear efficacy against Trichoderma aggressivum, the main mold causing economic losses during the cultivation of A. bisporus. To accompany the sector in this biological pathway, we have sequenced and studied the genome of this strain, in order to determine its biocontrol potential and its ability to form biofilms. We also evaluated the impact of this biofungicide on the dynamics of microbial communities in A. bisporus culture compost exposed or not to T. aggressivum. Finally, the study of the cellular reprogramming of this biocontrol agent during the culture in axenic micromodels allowed us a better understanding of the substrates colonization phenomenon and the inhibition of undesirable flora. This project will enrich the knowledge of the biocontrol mechanisms used in the mushroom industry and may allow a possible application to other agricultural sectors
Florian, Bianca [Verfasser], Wolfgang [Akademischer Betreuer] Sand und Hans-Curt [Akademischer Betreuer] Flemming. „Investigation of initial attachment and biofilm formation of mesophilic leaching bacteria in pure and mixed cultures and their efficiency of pyrite dissolution / Bianca Michaela Florian. Gutachter: Hans-Curt Flemming. Betreuer: Wolfgang Sand“. Duisburg, 2012. http://d-nb.info/1023643790/34.
Der volle Inhalt der QuelleCarvalho, Vanessa Rafaela de [UNESP]. „Determinação da diversidade bacteriana em culturas de caldo Macconkey de materiais clínicos de portadores de doença de Crohn e análise de propriedades de isolados de Escherichia coli identificados“. Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143087.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Desequilíbrio na composição de espécies bacterianas (disbiose) do intestino é uma característica da doença de Crohn (DC), a mais grave das doenças inflamatórias intestinais (DII). Na disbiose da DII, há um aumento de certos grupos de bactérias, tais como as Proteobacteria, em alguns pacientes. Acredita-se que o aumento destas bactérias deve contribuir para as reações inflamatórias responsáveis pelas lesões observadas no intestino de portadores de DC e retocolite ulcerativa, ao estimular a produção de citocinas por células locais do sistema imune. Proteobacteria, um dos filos predominantes da microbiota intestinal compreende bacilos gram-negativos, dos quais Escherichia coli (E. coli) é o mais conhecido. Dada a importância de Proteobacteria como patógeno ou membro da microbiota intestinal residente humana, este trabalho teve dois objetivos: 1) Investigar a ocorrência de variação numérica na população de Proteobacteria na DC e 2) Caracterizar amostras de E. coli encontradas nesta população, em relação a propriedades de virulência. Visando o primeiro objetivo, DNA de culturas em caldo MacConkey de diferentes materiais clínicos (fezes e biópsias intestinais) de 8 controles e 9 pacientes com DC foram amplificados com primers para as regiões V6-V8 do gene que codifica a fração 16S do rRNA (16S V6-V8 rDNA) e, em seguida, sequências específicas (representando táxons bacterianos particulares) contidas nos amplicons foram separadas por temperature gradient gel electrophoresis (TGGE), definindo perfis de banda que refletem a diversidade bacteriana. O segundo objetivo compreendeu a tipagem dos isolados de E. coli destas culturas através da classificação em filogrupos (A, B1, B2 e D) da coleção de referência de E. coli (EcoR), a pesquisa de sorogrupos O25 e O83, determinação das propriedades de aderência e capacidade de produzir biofilme. Análise de 32 culturas de 9 portadores de DC e 24 culturas de 8 controles mostrou uma clara diferença no número de bandas nos perfis de TGGE dos amplicons de 16S V6-V8 rDNA. Amplicons de 8 culturas de 9 portadores de DC tinham no máximo 2 bandas, ao passo que o número de bandas em amplicons de controles tinham pelo menos 3 bandas. Uma das bandas dos casos em que havia duas bandas ou a banda única dos perfis de cultura de casos teve a mesma mobilidade do amplicon de E. coli, colocado no gel como referência da corrida. PCR para detecção de genes de O25 e O83 demonstraram que estes sorogrupos foram dominantes tanto na população de E. coli de portadores de DC como de controles (apenas um paciente controle deu resultado negativo na PCR para ambos sorogrupos). Também, a maioria das cepas de E. coli, tanto de casos como de controles pertenceu ao filogrupo B2. Resultados parciais de testes de adesão em células Hep-2 revelaram que todos os pacientes (controles ou não) apresentaram E. coli aderentes, expressando o padrão agregativo. Testes para avaliar a capacidade de formação de biofilme indicaram que isolados de E. coli das regiões proximais encontrados em controles produzem biofilme de forma mais intensa do que isolados equivalentes de portadores de DC. Como conclusão, os dados apresentados sugerem que a população intestinal de Proteobacteria em portadores de CD apresenta disbiose, associada com um aumento do número de E. coli, uma propriedade que foi determinada por TGGE e confirmada com seqüenciamento de amplicons da região V6, pela técnica Ion Torrent. Por fim, com base nos resultados de tipagem e caracterização bacteriana foi possível observar que amostras tanto de caso como de controles, não houve uma prevalência dos sorogrupos e com base nesse resultado podemos associar que ambos os grupos de estudos freqüentam de forma rotineira o mesmo ambiente hospitalar, podendo indicar um favorecimento na aquisição desses tipos bacterianos. Resultados semelhantes ocorreram com as análises dos sorogrupos, onde apenas o filogrupo D teve prevalência significativa em indivíduos controle. Em relação à produção de biofilme, as amostras encontradas na região proximal do intestino de pacientes controles produzem mais biofilmes do que amostras de portadores de DC da mesma região intestinal, indicando que a parede da mucosa intestinal serve como substrato pode influenciar na formação do biofilme.
Imbalance in intestinal bacterial composition (dysbiosis) is a hallmark of Crohn’s disease (CD), the most severe of inflammatory bowel diseases (IBD). A characteristic of IBD dysbiosis is the elevation of certain groups of bacteria such as Proteobacteria in some patients. It is believed that the augmented bacteria may contribute for the inflammatory reactions underlying the typical lesions observed in the gut of CD and ulcerative colitis patients, by stimulating the production of cytokines by local cells of the immune system. Proteobacteria, one the most prevalent bacterial phyla of the gut microbiota are Gram negative rods of which Escherichia coli (E. coli) is the most well-known member. Given the significance of Proteobacteria as pathogens or member of resident gut microbiota, this work had two purposes: 1) to investigate the occurrence of numerical variation in the population of these bacteria in CD and 2) Characterizing E. coli isolates found in this population, in search for some virulence associated properties. For the first purpose, DNA from MacConkey broth cultures of distinct clinical materials (stools and gut mucosal biopsies) of 9 CD and 8 control patients were amplified with primers for the V6 and V8 regions of the 16S ribosomal RNA gene (16S V6-V8 rDNA) and distinct gene sequences (representing particular bacterial taxa) within the amplicons were resolved by temperature gradient gel electrophoresis (TGGE), defining band profiles, which reflect the bacterial diversity. The second objective consisted in phylotyping (determining A, B1, B2 and D phylogroups), serotyping (search for O25 and O83 genes), analyzing the E. coli isolates of the cultures for adherence properties and competence to produce biofilm. Analysis of 32 cultures from the 9 CD patients and 24 cultures from 8 control subjects showed a clear case-control difference in the number of bands in the TGGE profiles of the 16S V6-V8 rDNA amplicons. Cultures from 8 of 9 CD patients had at most 2 bands, while the number of bands in the cultures from 7 of the 8 controls subjects had at least 3 bands. One of the two bands found in the cultures from CD patients had the same mobility as E. coli, put in the gelas reference for the run. PCR screening for O25 and O83 demonstrated that these serogroups were dominant among the E. coli population from both controls and CD patients (only one control subject was negative for each of these O groups). Also, most of E. coli isolates from both control and CD patients belonged to the B2 phylogroup. Partial results of bacterial adherence to Hep-2 cells revealed that all patients (controls and CD) had aggregative adherent E. coli isolates. Tests to determine the ability to produce biofilm indicated that isolates from the proximal, but not from distal region of the gut or the stools, found in controls were stronger biofilm formers than isolates from equivalent sites of CD patients. In conclusion, the data presented here reveal that intestinal population of Proteobacteria of CD patients show dysbiosis associated with the elevation of Escherichia coli and that this variation can be assessed by TGGE and confirmed by sequencing of amplicons V6 region, the technique Ion Torrent. Finally, on the basis of the bacterial typing and characterization results, was observed that samples of both the case and controls, there was a prevalence of serogroups, based on this result we can associate both study groups frequent routinely the same hospital environment and may indicate a favoring the acquisition of these bacterial types. Similar results occurred with the analysis of serogroups, where only the filogrupo D had a significant prevalence in control subjects. For biofilm production, the samples found in the proximal region of the control patients intestine produce more biofilm than DC bearing samples of the same intestinal region, indicating that the intestinal mucosa serves as a substrate may influence the formation of biofilms.
FAPESP: 2013/04475-3
Bowler, Laura. „Pseudomonas aeruginosa biofilm and planktonic bacteria display different virulence mechanisms when co-cultured with human A549 lung cells using the Calgary Biofilm Device co-culture system“. American Society for Microbiology, 2012. http://hdl.handle.net/1993/31262.
Der volle Inhalt der QuelleMay 2016
Matsubara, Victor Haruo. „Efeito de bactérias probióticas sobre Candida albicans: ensaios em cultura de macrófagos e de biofilme“. Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/23/23150/tde-04112016-110527/.
Der volle Inhalt der QuelleThe infection rates of Candida albicans in human may be reduced by probiotics. However, the mechanisms involved in the interaction between C. albicans and probiotic bacteria are largely unknown. The present study comprised two parts. The first aimed to test the hypothesis that probiotics may impair the signaling induced by C. albicans in human macrophages, thus lowering the inflammatory challenge. The second aimed to evaluate the inhibitory effects of Lactobacillus on different phases of C. albicans biofilm development. In the first part, macrophages were pretreated with a probiotic strain (Lactobacillus rhamnosus LR32, Lactobacillus casei L324m and Lactobacillus acidophilus NCFM) and challenged with C. albicans and/or lipopolysaccharide (LPS) of Escherichia coli in a co-culture assay. After incubation, cytokine profile of macrophage\'s supernatant was assessed by ELISA and the expression of clec7a gene was determined by RT-qPCR. Probiotic strains altered the cytokine profile of macrophages stimulated with LPS and C. albicans, leading to increased levels of IL-10 and reduced levels of IL-12 (p<0.05), and reducing the relative expression of clec7a gene encoding Dectin-1 receptor (p < 0.05). In the second part, quantification of biofilm growth and microscopic analyses were performed on C. albicans biofilms treated with Lactobacillus cell suspensions and their supernatants. Lactobacilli induced a significant reduction (p<0,05) in the number of biofilm cells (25.5-61.8%) dependent on the probiotic strain and the biofilm phase. L. rhamnosus supernatants had no significant effect on the mature biofilm (p>0.05), but significantly reduced the early stages of Candida biofilm formation (p<0.01). Microscopic analyses revealed that L. rhamnosus suspensions reduced Candida hyphal differentiation, leading to a predominance of budding growth. All lactobacilli negatively impacted C. albicans yeast-to-hyphae differentiation and biofilm formation. The inhibitory effects of Lactobacillus on C. albicans involved both cell-cell interactions and secretion of exometabolites. To conclude, the probiotic lactobacilli reduce inflammation by impairing the recognition of C. albicans by macrophages and altering the production of proinflammatory cytokines. It was also clarified, for the first time, the mechanics of how the Lactobacillus species antagonize C. albicans colonization, particularly in the critical, early colonization phase of the yeast. Taken all together, our data elucidated the inhibitory mechanisms of lactobacilli that define their probiotic candicidal activity, supporting the use of these probiotics as a supplemental therapy against mucosal infections by C. albicans.
Ryšávka, Petr. „Tvorba biofilmu u probiotických kultur a možnosti jeho využití ve farmacii“. Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-438777.
Der volle Inhalt der QuelleDellias, Marina de Toledo Ferraz. „Comunidade bacteriana dos biofilmes da fermentação alcoólica: estrutura, composição, suscetibilidade aos antimicrobianos e formação de biofilme em culturas puras“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-01042016-091529/.
Der volle Inhalt der QuelleBioethanol production in Brazilian distilleries is based on fermentative activity of the yeast Saccharomyces cerevisiae which uses sugarcane juice and/or molasses as a substrate. Bacterial contaminants of alcoholic fermentation compete with yeasts for sugars, affecting ethanol yield and consequently causing relevant economic losses to the fuel ethanol industry. Biofilms formed into fermentors act as bacterial reservoirs, contributing to persistent contaminations that are difficult to control. Biofilms provide a certain degree of protection for their inhabitants against some environmental threats, including antibiotics. Thus, understanding bacterial community within biofilms is essential for actions to control contaminations in bioethanol production. In the first study, composition and dynamic of bacterial community were determined by 16S rRNA gene sequences analysis of biofilms with different growth periods, corresponding to initial stages of biofilm establishment in fermentation tanks. Results showed that these communities were dominated by lactic acid bacteria (LAB), mainly of the genus Lactobacillus. Visualization of biofilm structure by scanning electron microscopy revealed a mixed-species biofilm composed by bacteria and yeasts. In the second study, susceptibility to antimicrobials (monensina, virginiamicina and beta-acids from hops) and capacity to form biofilm in pure culture were evaluated for Lactobacillus spp. isolated from biofilms (sessile cells) and wine (planktonic cells) collected from fermentors. The results showed that differences in the susceptibility to antimicrobials and the ability to form biofilms were strain-specific and, in certain cases, the response of some species was related to the isolation source. This was the first investigation of contaminant biofilms from sugarcane-based alcoholic fermentation on an industrial scale
Pires, Juliana Gonçalves. „Comparação dos meios de cultura e das técnicas de quantificação de bactérias e fungos em reservatórios e tubulações de água de equipos odontológicos“. Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-07012015-094809/.
Der volle Inhalt der QuelleTwelve dental units of 7 clinics of FOB/USP were randomly selected, two were filled with distilled water (Orthodontics and Urgency), one with tap water (UBAs), one reservoir was dry for 30 days (Odontopediatry) and another for 60 days (Postgraduate Clinic), one dental unit was filled with the B - Safe ® technology (Multidisciplinary Clinic). Three dental clinics were evaluated concerning the cleaning procedure with enzymatic detergent. Samples of 10 mL of water reservoirs and high-speed handpieces were collected and made up to 10-4 dilutions, plated on R2A media, Peptone Diluted culture - PD, Plate Count Agar - PCA and Sabouraund Dextrose Agar - SDA. Aliquots of 100 L of the samples were plated on R2A media, PD, PCA and SDA culture technique for spreading. Aliquots of 25 L were seeded (R2A, PD, PCA and SDA) in drops and aliquots of 100 L samples were seeded in PCA by the pour plate technique. R2A plates, PD, PCA were incubated for 72 hours at 24°C and SDA plates for 4 to 7 days at 24°C. Bacterial identification was performed using Bactray I, II or III kit and fungal identification by microculture. Bacterial average was 128.151 CFU/mL in Odontopediatry, 1.834.807 CFU/mL in Orthodontics, 60.422 CFU/mL in Postgraduate Clinic, 615.68 CFU/mL in UBAs, 899.64 CFU/mL in Urgency, 97.632 CFU/mL in Multidisciplinary Clinic and 417.619 CFU/mL in Dentistry without the cleaning procedure and 135.924 CFU/mL after it. The average of fungi was 205 CFU/mL in Odontopediatry, 702.50 CFU/mL in Orthodontics, 12.50 CFU/mL in Postgraduate Clinic, 41.475 CFU/mL in UBAs, 117.500 CFU/mL in Urgency, 4.469 CFU/mL in Multidisciplinary and 64.642 CFU/mL and 23.627 CFU/mL before and after cleaning procedure in Dentistry. The presence of micro - organisms occurred in reservoirs and waterlines in all of the 7 clinics evaluated. To quantify bacteria, R2A and PD medium provided more accurate results than PCA. To detect different species, PCA medium was better than R2A and PD. The drop technique was better than the spreading technique and pour plate for bacteria; however, the spreading technique provided better results for the yeasts. The enzymatic detergent was effective on disrupting the biofilm eliminating more yeasts than residual bacteria. Twenty-two species of bacteria were identified: Acinetobacter baumanni/calcoaceticus, Aeromonas hydrophila, Alcaligenes xylosoxidans denitrificans, Brevundimonas vesicularis, Burkholderia cepacia, Burkholderia pseudomallei, Chromobacterium violaceum, Hafnia alvei, Hafnia alvei (Biogroup 1), Ochrobactrum anthropi, Pseudomonas aeruginosa, Pseudomonas alcaligenes, Pseudomonas fluorescens, Pseudomonas luteola, Pseudomonas oryzihabitans, Pseudomonas pseudoalcaligenes, Pseudomonas putida, Pseudomonas stutzeri, Serratia liquefaciens, Serratia plymuthica, Sphingobacterium multivorum, Tatumella ptyseos. Twelve genus of fungi were identified: Acremonium sp, Alternaria sp, Aspergillus sp, Cladosporium sp, Curvularia sp, Exophiala sp, Fonsecaea sp, Fusarium sp, Paecylomices sp, Penicillium sp, Rhinocladiella sp, Verticillium sp.
Carvalho, Vanessa Rafaela de. „Determinação da diversidade bacteriana em culturas de caldo Macconkey de materiais clínicos de portadores de doença de Crohn e análise de propriedades de isolados de Escherichia coli identificados“. Botucatu, 2016. http://hdl.handle.net/11449/143087.
Der volle Inhalt der QuelleResumo: Desequilíbrio na composição de espécies bacterianas (disbiose) do intestino é uma característica da doença de Crohn (DC), a mais grave das doenças inflamatórias intestinais (DII). Na disbiose da DII, há um aumento de certos grupos de bactérias, tais como as Proteobacteria, em alguns pacientes. Acredita-se que o aumento destas bactérias deve contribuir para as reações inflamatórias responsáveis pelas lesões observadas no intestino de portadores de DC e retocolite ulcerativa, ao estimular a produção de citocinas por células locais do sistema imune. Proteobacteria, um dos filos predominantes da microbiota intestinal compreende bacilos gram-negativos, dos quais Escherichia coli (E. coli) é o mais conhecido. Dada a importância de Proteobacteria como patógeno ou membro da microbiota intestinal residente humana, este trabalho teve dois objetivos: 1) Investigar a ocorrência de variação numérica na população de Proteobacteria na DC e 2) Caracterizar amostras de E. coli encontradas nesta população, em relação a propriedades de virulência. Visando o primeiro objetivo, DNA de culturas em caldo MacConkey de diferentes materiais clínicos (fezes e biópsias intestinais) de 8 controles e 9 pacientes com DC foram amplificados com primers para as regiões V6-V8 do gene que codifica a fração 16S do rRNA (16S V6-V8 rDNA) e, em seguida, sequências específicas (representando táxons bacterianos particulares) contidas nos amplicons foram separadas por temperature gradient gel electrophores... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Imbalance in intestinal bacterial composition (dysbiosis) is a hallmark of Crohn’s disease (CD), the most severe of inflammatory bowel diseases (IBD). A characteristic of IBD dysbiosis is the elevation of certain groups of bacteria such as Proteobacteria in some patients. It is believed that the augmented bacteria may contribute for the inflammatory reactions underlying the typical lesions observed in the gut of CD and ulcerative colitis patients, by stimulating the production of cytokines by local cells of the immune system. Proteobacteria, one the most prevalent bacterial phyla of the gut microbiota are Gram negative rods of which Escherichia coli (E. coli) is the most well-known member. Given the significance of Proteobacteria as pathogens or member of resident gut microbiota, this work had two purposes: 1) to investigate the occurrence of numerical variation in the population of these bacteria in CD and 2) Characterizing E. coli isolates found in this population, in search for some virulence associated properties. For the first purpose, DNA from MacConkey broth cultures of distinct clinical materials (stools and gut mucosal biopsies) of 9 CD and 8 control patients were amplified with primers for the V6 and V8 regions of the 16S ribosomal RNA gene (16S V6-V8 rDNA) and distinct gene sequences (representing particular bacterial taxa) within the amplicons were resolved by temperature gradient gel electrophoresis (TGGE), defining band profiles, which reflect the bact... (Complete abstract click electronic access below)
Mestre
Fregard, Florence. „Rôle des interactions hydrophobes et électrostatiques dans l'adhésion de bactéries méthanogènes aux matériaux de faible énergie de surface“. Lille 1, 1991. http://www.theses.fr/1991LIL10047.
Der volle Inhalt der QuelleSilva, Eliane Pereira da. „Influência da temperatura, de enzimas degradantes de DNA e do sobrenadante de cultura de estafilococos na formação de biofilme por Listeria monocytogenes em superfície abiótica“. Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-19122013-103644/.
Der volle Inhalt der QuelleListeriosis is a rare and serious mainly food-borne infection. It is caused by the bacterium Listeria monocytogenes that primarily affects pregnant women and immunologically compromised individuals. This pathogen is recognized as a problem for the food industry due to its ability to form biofilms. Biofilms are microbial communities adhered to biotic or abiotic surfaces embebed by self produced extracellular polymers. These structures are resistant to cleaning and disinfection procedures, allowing the survival and persistence of L. monocytogenes in food processing environments. Thus, several strategies have been adopted to prevent and control the formation of biofilms on food contact surfaces. The present study investigated biofilm formation by L. monocytogenes on abiotic surface at different temperatures, in the presence of DNA degrading enzymes (DNAses) and in the presence of culture supernatant with and without staphylococcal thermonuclease activity. For this purpose, we used culture techniques and microscopy. The results showed that L. monocytogenes was able to adhere on stainless steel surface on average 105-106 CFU per cm2. The different incubation temperatures affected the adhesion of L. monocytogenes on stainless steel surface, although other factors in combination were also involved, such as the bacterial strain and the type of system used for assay. By fluorescence microscopy, we noticed the formation of mature biofilms by L. monocytogenes, with channels likely involved in flow of nutrients and holes typical of cell dispersion. Furthermore, we found a predominance of metabolically active cells surrounded by extracellular matrix polymer containing extracellular DNA (eDNA) stained with acridin orange. By laser confocal microscopy, we observed the formation of microcolonies containing eDNA and homogeneous thin layer of viable cells stained with SYTO 9 and DDAO. The eDNA was also observed in locations with absence of cells characteristics of cell dispersion. The culture supernatant of S. aureus with thermonuclease activity was able to inhibit L. monocytogenes free on culture medium and interfered with the formation of biofilm by the pathogen for up to 24h at 37°C. The commercial DNAses did not affect biofilm formation by L. monocytogenes, possibly excluding the action of thermonuclease of S. aureus on the inhibition of planktonic or sessile forms of L. monocytogenes. It has been found a production of a thermostable protein by S. aureus and it was able to inhibit L. monocytogenes in agar antagonism assays but further studies are needed to characterize such inhibitory substance.
Machado, Juliana de Carvalho [UNESP]. „Efeito da combinação de antibióticos e sinvastatina sobre microrganismos de interesse endodôntico e na expressão de marcadores odontoblásticos“. Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138844.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Terapias biológicas tem buscado novas substâncias/protocolos que promovam a eliminação microbiana e induzam ou estimulem a regeneração pulpar e o desenvolvimento completo radicular de dentes permanentes jovens com processos patológicos pulpares. Os objetivos do estudo foram avaliar a a tividade antimicrobiana/antibiofilme de algumas combinações de antibióticos sobre microrganismos de interesse endodôntico e analisar o efeito da combinação de antibióticos com melhor ação antimicrobiana associada à sinvastatina na expressão de marcadores odontoblásticos em células da polpa dental humana (CPDH). A atividade antimicrobiana dos seguintes antibióticos : Metronidazol (ME), Ciprofloxacina (CI), Minociclina (MI), Doxicilina (DO) e Fosfomicina (FO), isolados ou em combinação dupla (ME+CI, ME+MI, ME+DO, ME+FO, CI+MI, CI+DO, CI+FO, DO+FO, MI+FO) ou tripla (ME+CI+MI, ME+CI+FO, ME+MI+FO, ME+CI+DO, ME+DO+FO, CI+DO+FO, CI+MI+FO) foram testados contra Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii e Candida albicans em condições planctônicas. Biofilmes mono-espécie de E. faecalis e biofilmes em dual-espécies de E. faecalis and C. albicans foram preparados em blocos de dentina para testar a atividade antibiofilme das combinações de antibióticos com os melhores resultados microbiológicos. O efeito antibiofilme das combinações antibióticas sobre biofilme de E. faecalis dentro dos túbulos dentinários foi também avaliada por microscopia confocal. Culturas de CPDH foram expostas à combinação antibiótica com melhor resultado microbiológico e sinvastatina e determinada a viabilidade celular, atividade da fosfatase alcalina (ALP), deposição de nódulos de mineralização e expressão de DSPP (sialofosfoproteína dentinária), importante marcador odontoblástico de mineralização denti nária. Os dados foram 9 analisados estatisticamente, considerando p<0,05 . Todas as combinações de antibióticos reduziram o crescimento bacteriano, exceto por CI+DO e DO+FO para A. Israelii. ME+CI+MI e ME+MI+FO inibiram significantemente o crescimento de A. israelii e E. faecalis, e ME+MI+FO eliminou S. mutans. ME+MI+FO e ME+CI+FO tiveram o melhor efeito contra biofilme de E. faecalis, em mono ou dual-espécies e dentro dos túbulos dentinários. CI e ME+CI+FO afetaram a viabilidade das células pulpares, em 1 e 7 dias. A atividade de ALP aumentou com a presença de sinvastatina para todos os grupos, exceto para CI e ME+CI+FO. Grupos contendo sinvastatina mostram maior deposição de nódulos de mineralização e expressão de DSPP que os grupos sem sinvastatina. Pode-se concluir que a combinação de antibióticos tripla ME+CI+FO teve efeito marcante contra os microrganismos endodônticos, em condições planctônicas e em biofilme. A sinvastatina estimulou a expressão de marcadores odontoblásti cos de mineralização dentinária pelas HDPC; entretanto, seu efeito foi reduzido pela presença da CI.
Biological therapies have searching for substances/protocols, which promote microbial elimination and induce or stimulate pulp regeneration and completion of apical root development in young permanent teeth with pulp pathological processes . The objectives of this study were to evaluate the antimicrobial /anti-biofilm activity of some antibiotics combinations on endodontic microorganisms and the effect of the combination of antibiotics with the best antimicrobial action associated with simvastatin on expression of odontoblast markers by human dental pulp cells (HDPC). The antimicrobial activity of the following antibiotics : Metronidazole (ME), Ciprofloxacin (CI), Minocycline (MI), Doxycycline (DO) and Fosfomycin (FO), either alone or in double (ME+CI, ME+MI, ME+DO, ME+FO, CI+MI, CI+DO, CI+FO, DO+FO, MI+FO) or triple combinations (ME+CI+MI, ME+CI+FO, ME+MI+FO, ME+CI+DO, ME+DO+FO, CI+DO+FO, CI+MI+FO) were tested against Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii and Candida albicans in planktonic conditions. Mono-species biofilm of E. faecalis and dual-species biofilms of E. faecalis and C. albicans were prepared in dentin blocks to test the anti -biofilm activity of antibiotic combinations with the best microbiological results. Antibiofilm effect of antibiotic combination on E. faecalis biofilm inside dentin tubules was also evaluated by confocal microscopy. Cultures of HDPC were exposed to the antibiotic combination with the best antimicrobial effect and simvastatin and determined cell viability, alkaline phosphatase activity, deposition of mineralization nodules and expression of Dspp (dentin sialophosphoprotein), important odontoblast markers of dentin mineralization. Data were analyzed statistically, considering p<0.05. All antibiotic combinations reduced statistically the growth of bacteria tested, except by CI+DO and DO+FO for A. israelii. ME+CI+MI and ME+MI+FO inhibited significantly growth of A. 11 israelii and E. faecalis, and ME+MI+FO eliminated S. mutans. ME+MI+FO and ME+CI+FO had the best effect against E. faecalis biofilm, in mono and dual -species biofilms and inside dentin tubules, similar to CHX. CI and ME+CI+FO affected HDPC viability, 1 and 7 days. ALP activity increased with the presence of simvastatin for all groups, except by CI and ME+CI+FO. Groups containing simvastatin had higher mineralized nodule deposition and higher DSPP expression than groups without simvastatin. It can be concluded that triple antibiotic combination of ME+CI+FO ha d remarkable effect against endodontic microorganisms, in planktonic and biofilm conditions. Simvastatin stimulated the expression of odontoblast markers of dentin mineralization by HDPC; however, its effect was reduced i n the presence of CI.
FAPESP: 2014/00589-7
Wolfaardt, Gideon Malherbe. „Accumulation and degradation of diclofop methyl by cultured biofilm communities“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1994. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq23927.pdf.
Der volle Inhalt der QuelleRatti, Regiane Priscila. „\'Listeria monocytogenes\' em alimentos fatiados e equipamentos: ocorrência, formação de biofilme e controle“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-01042009-112327/.
Der volle Inhalt der QuelleListeria monocytogenes is the causal agent of listeriosis, an infection that targets mainly pregnant women (and their fetuses), children, the elderly and immunocompromised individuals. Listeriosis represents the majority of fatal cases of foodborne diseases. Foods are recognized as primary sources of transmission of this bacterium to man and L. monocytogenes has been isolated from of a great variety of foods. Surfaces of equipments used in the production of foods can harbour L. monocytogenes. Failures in sanitization procedures can leave food residues adhered to equipments of food processing and L. monocytogenes can attach to abiotic surfaces, multiply and form biofilms. Interactions among bacteria of diverse species may influence biofilm formation by L. monocytogenes and this is an important issue to be studied to improve food safety. Leuconostoc mesenteroides is a lactic bacterium usually found in foods and some strains can interfere with the multiplication of L. monocytogenes by production of bacteriocins with antilisterial activity. Biofilms represent a special concern to the food industry, because adhered microorganism are generally more resistant to antimicrobial treatments. In this work, we collected 30 samples of sliced cooked ham, 30 of sliced mozzarella cheese and 30 of surfaces of food processing equipments, in the retail market of the city of Ribeirão Preto - SP. The samples were studied for presence or absence of L. monocytogenes. The ability of the isolates to form biofilms was also studied, in pure and in co-culture tests. The sanitizer peracetic acid and the bacteriocin nisin were tested to control biofilm formation by L. monocytogenes. L. monocytogenes formed biofilm on stainless steel coupons when cultivated alone or in co-culture with L. mesenteroides. The treatment of stainless steel coupons with peracetic acid inactivated the cells of the biofilm. Under the experimental conditions tested nisin did not present activity against L. monocytogenes in biofilms.
Azarnoush, Kian. „The Effects of Amixicile on Sub-gingival Biofilm Cultured from Humans“. VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5349.
Der volle Inhalt der QuelleDias, Kássia de Carvalho. „Efeito das toxinas microbianas provenientes de biofilme simples ou misto de Staphylococcus aureus e Candida albicans sobre monoculturas ou culturas 3D de células da mucosa oral /“. Araraquara, 2016. http://hdl.handle.net/11449/148693.
Der volle Inhalt der QuelleResumo: Esta presente tese foi dividida em quatro estudos que tiveram como objetivos. 1. Validar um protocolo e comparar o efeito dos tampões RPMI/MOPS e RPMI/HEPES no desenvolvimento de biofilmes e na viabilidade celular de queratinócitos (NOK-si e HaCat); 2. Comparar o dano celular e a resposta inflamatória induzidos pelos metabólitos de biofilmes simples e misto de Staphylococcus aureus e Candida albicans; 3. Avaliar o tipo de morte celular (apoptose vs. necrose) e a ativação de caspases relacionadas aos metabólitos desses biofilmes e 4. Caracterizar um tecido oral reconstituído e analisar o dano tecidual causado pelo sobrenadante e biofilme propriamente dito desses microrganismos. No estudo 1, a viabilidade celular foi avaliada pelo método colorimétrico do MTT e por imagens da cultura após 12 horas em contato com os meios de cultura. Ambos os tampões permitiram similar crescimento do biofilme. Efeito citotóxico do MOPS foi verificado após 6 horas de crescimento de NOK-si e HaCat. Houve preservação da viabilidade e morfologia quando as células foram expostas a RPMI/HEPES. Conclui-se que RPMI/HEPES pode ser utilizado como um meio tamponamente viável para estudos que avaliam o efeito do biofilme em cultura de queratinócitos ao longo do tempo. No estudo 2, o sobrenadante dos biofilmes de 36 h de C. albicans e S. aureus, isolados ou em associação, foi colocado em contato com NOK-si, HaCat e macrófagos (J774A.1). O dano celular foi avaliado por meio de ensaios de viabilidade celular ... (Resumo completo, clicar acesso eletrônico abaixo)
The present thesis was divided into four studies with the following objectives. 1. Validate a protocol and compare the effect of RPMI/MOPS and RPMI/HEPES buffers on the development of biofilms and keratinocyte cell viability (NOK-si and HaCat); 2. Compare the cellular damage and the inflammatory response induced by the metabolites of simple and mixed biofilms of Staphylococcus aureus and Candida albicans; 3. Evaluate the type of cell death (apoptosis vs. necrosis) and the activation of caspases related to the metabolites of these biofilms and 4. Characterize the reconstituted oral tissue and analyze the tissue damage caused by the supernatant and biofilm of these microorganisms. In study 1, cell viability was evaluated by the MTT colorimetric method and by culture images after 12 hours in contact with the culture media. Both buffers permitted similar biofilm growth. The cytotoxic effect of MOPS was observed after six hours of NOK-si and HaCat growth. There was preservation of viability and morphology when cells were exposed to RPMI/HEPES. It was concluded that RPMI/HEPES can be used as a buffering medium for studies evaluating the effect of biofilm on keratinocyte culture over time. In study 2, the supernatant of the 36-hour biofilms of C. albicans and S. aureus, isolated or in combination, was placed in contact with NOK-si, HaCat and macrophages (J774A.1). Cell damage was assessed by cell viability assays (MTT) and LDH enzyme release. Cytokine production was analyzed by the ELISA method and evaluation of the type of cell death by the staining of the apoptotic cells with annexin V and the necrotic cells with propidium iodide. The mixed biofilm and biofilm of C. albicans were more cytotoxic, and the mixed biofilm caused greater cellular damage through the release of the LDH enzyme. S. aureus biofilm metabolites stimulated greater production of NO, IL-6 and TNF-α... (Complete abstract electronic access below)
Doutor
Olivares, Elodie. „Évaluation de l'impact des antibiotiques sur la formation de biofilms par P. aeruginosa : place de l'Antibiofilmogramme®“. Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ074/document.
Der volle Inhalt der QuelleCystic fibrosis (CF) patients are predisposed to chronic colonisation of the upper airways by P. aeruginosa. This opportunist pathogen is characterized by its ability to adhere to a surface and to form a protective biofilm, which is highly tolerant to antimicrobials. In routine, antibiograms are realised on planktonic bacterial cultures. The efficacy of the corresponding antimicrobial therapies appears low for the eradication of bacterial biofilms. The realisation of Antibiofilmograms® on CF clinical isolates (a new tool investigating the susceptibility of sessile bacteria to antibiotics) highlighted phenomena of biofilm formation inhibition and induction. More precisely, aminoglycosides are able to delay the bacterial adherence. Conversely, the β-lactam family shows the ability to stimulate the early adhesion of microorganisms. These different effects of antimicrobials on the bacterial behaviour are confirmed with more conventional in vitro methods (Crystal Violet, enzymatic treatment with DNase I) and a cell model (static co-culture of eukaryotic cells and bacteria). The clinical relevance of the Antibiofilmogram® is reinforced by its ability to detect the initiation of the early bacterial adhesion, to select inhibitor molecules and to avoid the inducer ones. Associated to traditional antibiograms, its application should be pertinent to optimise the CF therapies for the treatment of chronic lung infections
Baillif-Gostoli, Stéphanie. „Étude de l'adhérence et de la formation des biofilms à staphylococcus epidermidis sur des implants intraoculaires de biomatériaux différents dans des conditions expérimentales dynamiques“. Lyon 1, 2008. http://www.theses.fr/2008LYO10099.
Der volle Inhalt der QuellePostoperative endophthalmitis remains a serious sight threatening complication of intraocular surgery. Staphylococcus epidermidis is currently recognized as an important etiological agent of endophthalmitis after cataract surgery. It is characterised by its ability to adhere to polymer surfaces such as intraocular lenses (IOLs). The binding of bacteria is the first step in IOL colonization. It is followed by bacterial accumulation in multilayered cell clusters embedded in an exopolysaccharide matrix leading to the formation of a confluent structured biofilm. Biofilm formation on polymer surfaces is a complex process that depends on bacterial cell surface characteristics, on the nature of the polymer material and on environmental factors. Numerous studies have tried to investigate the interactions between bacteria and different types of IOLs so as to determine which biomaterial would be more permissive to bacterial adherence. But large discrepancies were found between the data. Moreover, the lack of similarity between the selected experimental conditions and intraocular physiological ones made it difficult to extrapolate the in vitro results to the clinical situation. To overcome these problems, we designed an in vitro model that more closely resembled intraocular conditions. Our developed model allowed the study of Staphylococcus epidermidis biofilm formation (from the primary attachment phase to the biofilm maturation phase) on intraocular lenses. It also showed significant differences in bacterial adhesion among IOL materials. Adherence was weakest on the hydrophilic acrylic polymer and strongest on the silicone polymer, more hydrophobic. Bacterial adhesion and biofilm development on the implant surface must therefore depend on biomaterial characteristics particularly on its hydrophobic or hydrophilic nature
Moretti, Paul. „Performances, modélisation et limites d'un procédé à lit fluidisé associant culture libre et fixée (IFAS) pour le traitement du carbone et de l'azote des eaux résiduaires“. Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10214/document.
Der volle Inhalt der QuelleMotivated by the increasingly demanding discharge consents and by the need to improve overall treatment capacity, water authorities are uninterruptedly examining better performing and more compact wastewater treatment technologies. Thanks to its compactness and to its capacity to treat both organic matter and nitrogen at an affordable cost, the IFAS process represents an attractive addition to improve retrofitting-activated sludge plants performance. The main objective of this thesis is to optimize IFAS process with regards to key operation parameters such as dimensioning, F/M ratio by combining experimental and mathematical modelling approaches. A 3 m3 pilot IFAS fed with raw wastewater was operated at the experimental hall of La Feyssine wastewater treatment plant, Villeurbanne, for a period of 2 years. The IFAS process was separated in 3 tanks to treat organic matter and total nitrogen separately (anoxic/aerobic, suspended/aerobic IFAS). The experimental study was divided in 7 periods with different steady state operation conditions each. The feasibility of nitrification at steady F/M ratios (between 0,1S to 0,30 kgBODS/kgMLVSS/d), at constant temperatures (between 10 - 22°C) and at different oxygen supply rates was investigated. TSS in mixed liquor were maintained at 2,3 gMLTSS/L and oxygen concentration between 2 to 6 mgO2/L. Biofilm mass and combined nitrification capacity of biofilm and mixed liquor (NPRmax) were measured on a weekly basis. The removal performance was up to 90% for nitrogen and carbon treatment with a maximal F/M ratio of 0,30 kgBODS/kgMLVSS/d between 16°C to 24 °C. The biofilm was able to nitrify 0,90 gN/m2/d (NPRmax) depending on the oxygen concentration in the mixed liquor (diffusional limitation). Under the operating conditions tested in this study, biofilm was responsible for 40 to 70% of NOx-N production in IFAS reactor during nitrification. Decreasing the MLSRT to less than 4 days limits the growth of autotrophic bacteria in the mixed liquor but does not halt it completely
Sousa, Denise Lins de. „Efeito antibacteriano do acido anacÃrdico em culturas planctÃnicas e biofilmes de Streptococcus mutans“. Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11650.
Der volle Inhalt der QuelleÃcido anacÃrdico à um composto extraÃdo do lÃquido da castanha de caju (LCC) e tem emergido como um composto promissor devido a sua variedade de propriedades biolÃgicas. Este estudo està dividido em trÃs capÃtulos, cujos objetivos foram: capÃtulo 1) investigar a atividade antibacteriana de uma emulsÃo de Ãcidos anacÃrdicos, extraÃdos do LCC, e de uma emulsÃo sintÃtica do Ãcido anacÃrdico, em culturas planctÃnicas de Streptococcus mutans, bem como avaliar sua citotoxicidade in vitro; capÃtulo 2) avaliar o efeito de diferentes concentraÃÃes de uma emulsÃo de Ãcidos anacÃrdicos extraÃdos do LCC em biofilmes maduros de S. mutans; e capÃtulo 3) avaliar o efeito da aplicaÃÃo Ãnica versus aplicaÃÃo duas vezes ao dia de diferentes concentraÃÃes de uma emulsÃo de Ãcidos anacÃrdicos em biofilmes de S. mutans. A atividade antibacteriana das emulsÃes foi determinada atravÃs da concentraÃÃo inibitÃria mÃnima (CIM) e concentraÃÃo bactericida mÃnima (CBM), e a citotoxicidade foi mensurada atravÃs do reagente CellTiter Blue (capÃtulo 1). Biofilmes foram crescidos em discos de hidroxiapatita imersos em caldo de peptona caseÃna soja e extrato de levedura com 1% sacarose por cinco dias. Biofilmes foram tratados com a emulsÃo de Ãcidos anacÃrdicos por um minuto no Ãltimo dia do experimento para avaliar seu efeito em biofilme maduro; viabilidade bacteriana e mensuraÃÃo de peso seco foram realizadas (capÃtulo 2). Diferentes concentraÃÃes da emulsÃo de Ãcidos anacÃrdicos foram aplicadas apenas no Ãltimo dia do experimento e duas vezes ao dia durante cinco dias para avaliar o efeito de diferentes aplicaÃÃes da emulsÃo de Ãcidos anacÃrdicos em biofilmes de S. mutans; viabilidade bacteriana, mensuraÃÃo de peso seco e quantificaÃÃo de polissacarÃdeos foram realizados (capÃtulo 3). A CIM e CBM da emulsÃo de Ãcidos anacÃrdicos (LCC) em cultura planctÃnica foram 0,48 μg/ml; e a CIM da emulsÃo sintÃtica do Ãcido anacÃrdico foi 4,38 μg/ml, mas sua CBM nÃo pÃde ser determinada (> 3.200 μg/ml) (capÃtulo 1). Observou-se uma reduÃÃo significante na viabilidade bacteriana de biofilmes maduros apÃs tratamento com as concentraÃÃes da emulsÃo de Ãcidos anacÃrdicos, mas estas nÃo alteraram o peso seco do biofilme (capÃtulo 2). O tratamento diÃrio com diferentes concentraÃÃes da emulsÃo de Ãcidos anacÃrdicos reduziu a viabilidade bacteriana do biofilme e modificou os nÃveis de polissacarÃdeos intracelular e extracelulares (capÃtulo 3). Pode-se concluir que a emulsÃo de Ãcidos anacÃrdicos apresenta-se como um promissor agente antibacteriano, tendo a capacidade de reduzir a viabilidade do S. mutans tanto em culturas planctÃnicas quanto em biofilmes.
Anacardic acid is an extract from processing of cashew nut shell liquid (CNSL) and it has been recognized to have several biological activities. This study is divided into three chapters, whose aims were: chapter 1) to investigate the antibacterial activity of an anacardic acids emulsion, from CNSL, and a synthetic emulsion of anacardic acid on planktonic cultures of S. mutans as well as to evaluate its cytotoxic effect in vitro; chapter 2) to evaluate the effect of different concentrations of an anacardic acids emulsion on Streptococcus mutans mature biofilm; and chapter 3) to evaluate the effect of a single and daily treatment of an anacardic acids emulsion on Streptococcus mutans biofilm. The antibacterial activity of the emulsions was determined using the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and the cytotoxicity was evaluated using CellTiter-Blue cell viability (chapter 1). The biofilms were grown on hydroxyapatite discs and immersed in tryptone yeast-extract broth containing 1% (w/v) sucrose for 5 days. The biofilms were exposed to anacardic acids emulsion for 1 min on the last day of experiment to evaluate its effect on mature biofilm; bacterial viability and dry weight were analyzed (chapter 2). Different concentrations of anacardic acids emulsion were applied on the last day of the experiment and twice daily until the fifth day to evaluate the effects of different treatments of anacardic acids emulsion on S. mutans biofilms; bacterial viability, dry weight and polysaccharides were analyzed (chapter 3). The MBC and MIC of the anacardic acids emulsion (from CNSL) on planktonic culture were 0.48 μg/ml; the MIC of the synthetic emulsion of anacardic acid was 4.38 μg/ml, but the MBC could not be determined (> 3,200 μg/ml) (chapter 1). Significant decreases in the viability of mature biofilms were observed after anacardic acids emulsion treatment, but they did not change the amount of dry weight (chapter 2). The daily treatment with different concentrations of anacardic acids emulsion decreased the bacterial viability and modified the polysaccharides levels on biofilm (chapter 3). We concluded that anacardic acids emulsion is a promising antibacterial agent, and it can decrease S. mutans viability in planktonic cultures and in biofilms.
Elliott, D. R. „Canine oral biofilms : cultural, molecular, and in vitro studies“. Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444703/.
Der volle Inhalt der QuelleZoccolotti, Jacqueline de Oliveira. „Avaliação de propriedades físicas, mecânicas e biológicas de uma resina acrílica para base de próteses após imersão em soluções de sabonetes líquidos desinfetantes : efeito de tempo de imersão /“. Araraquara, 2017. http://hdl.handle.net/11449/150642.
Der volle Inhalt der QuelleResumo: A desinfecção química associada ao método mecânico tem sido recomendada para a higienização de próteses removíveis parciais ou totais. Levando-se em consideração as desvantagens dos agentes químicos de limpeza utilizados para a desinfecção ou redução do biofilme das próteses, como o manchamento, branqueamento e corrosão das partes metálicas, novos estudos são necessários. Assim, o objetivo deste estudo foi avaliar as propriedades biológicas, físicas e mecânicas de uma resina acrílica para base de próteses após imersão em sabonetes líquidos desinfetantes, nas suas concentrações inibitórias minímas (CIM) para Candida albicans, após diferentes períodos de tempo. Primeiramente, a CIM de cada sabonete foi determinada. Amostras de resina acrílica (Vipi Wave®) foram confeccionadas e divididas em grupos para avaliação da capacidade de formação de biofilme (n=6), citotoxicidade (n=9), rugosidade (n=15), dureza (n=15) e alteração de cor (n=15), após imersão por 0, 7, 14, 21 e 28 dias, nas seguintes soluções: AD: imersão em água destilada a 37°C (grupo controle); SD: ciclos de imersão diária em sabonete Dettol®® a 0,39%, por 8 horas a temperatura ambiente, seguido de imersão em água destilada por 16 horas a 37°C, simulando a desinfecção noturna das próteses; SP: ciclos de imersão diária em sabonete Protex® a 3,12%, conforme descrito para o grupo anterior. SL: ciclos de imersão diária em sabonete Lifebuoy® a 0,78%, conforme descrito para o grupo SD. Além disso, a redução do biofilme de C... (Resumo completo, clicar acesso eletrônico abaixo)
Chemical disinfection associated with the mechanical method has been recommended for the cleaning of partial or full dentures. Taking into consideration the drawbacks of the cleaning chemicals used for disinfection or reduction of biofilm of prostheses, such as staining, bleaching and corrosion of metal parts, further studies are needed. The objective of this study was to evaluate the biological, physical and mechanical properties of an acrylic resin for denture base (Vipi Wave®) after immersion in liquid disinfectant soaps in their minimum inhibitory concentrations (MIC) for Candida albicans, after different periods of time. Samples of acrylic resin (Vipi Wave®) were made. Samples from acrylic resin (Vipi Wave®) were made and shared in groups for the assessment of the biofilm formation capacity (n=6), cytotoxicity (n=9), roughness (n=15), hardness (n=15) and color change (n=15) after immersion in the following solutions for 0, 7, 14, 21 and 28 days: AD: immersion in distilled water at 37 ° C (control group); SD: daily immersion cycles in soap Dettol® 0.39% for 8 hours at room temperature, followed by soaking in distilled water for 16 hours at 37 ° C, simulating the night disinfection of prostheses; SP: daily immersion cycles in soap Protex® to 3.12%, as described for the previous group. SL: daily immersion cycles in Lifebuoy® in soap to 0.78%, as described for the SD group. In soap Dettol® was found the MIC of 0.39% of the soap concentration; in Protex® 3.12% and in Lifebuoy® the MIC was 0.78%. In addition, capacity of reduction of the biofilm of Candida albicans formed on the surface of samples (n = 9) immersed for 8 hours (overnight) in the solutions was also evaluated. To know the biofilm-forming capacity, there were the forming unit count tests of colonies and alamarBlue® ...(Complete abstract electronic access below)
Mestre
Rocha, José Francisco Santos Simões da. „Efeito do processo de envelhecimento sobre propriedades físicas e biológicas de biomateriais utilizados como abutments /“. Araraquara, 2018. http://hdl.handle.net/11449/157417.
Der volle Inhalt der QuelleResumo: O objetivo deste estudo foi avaliar o efeito do envelhecimento de materiais comumente usados como pilares de próteses implanto-suportadas (abutments) sobre suas características físicas de superfície (rugosidade, energia livre de superfície e molhabilidade) e propriedades biológicas (metabolismo de fibroblastos orais e formação de biofilme fúngico). Para isso, discos (N=62) com rugosidade inferior a 0,2 µm foram confeccionados em zircônia (ZrO2) do tipo Y-TZP (yttriumstabilized tetragonal zirconia polycrystalline) e em titânio (Ti) comercialmente puro, e foram submetidos a um processo de envelhecimento simulado em autoclave a 134ᵒC (pressão de 2 bar) por 20 horas. ZrO2 e Ti envelhecidos foram comparados aos seus homólogos não envelhecidos. Os materiais também foram comparados entre si, nas condições envelhecida e não envelhecida. Para os testes biológicos, os grupos também foram comparados a um controle positivo de poliestireno. Todos os testes, exceto o de rugosidade, foram realizados após a formação de película salivar sobre os discos. Os testes biológicos utilizados foram de Alamar Blue (n=9) para avaliar o metabolismo de fibroblastos da gengiva humana (FGH) e de contagem de colônias viáveis (n=9) para verificar a formação de biofilme de uma cepa padrão de Candida albicans (ATCC90028) sobre os materiais. Além disso, microscopia eletrônica de varredura (MEV) (n=2) foi realizada para avaliação da morfologia dos fibroblastos e dos microrganismos. Para a análise estatística, fo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to evaluate the effect of aging of commonly used abutments on their surface physical characteristics (roughness, surface free energy and wettability) and biological properties (oral fibroblasts metabolism and formation of fungal biofilm). For this purpose, discs (N=62) with roughness less than 0.2 μm were made in yttrium-stabilized tetragonal zirconia polycrystalline (Y-TZP) zirconia (ZrO2) and in commercially pure titanium (Ti), and underwent a simulated aging process in autoclave at 134 °C (pressure of 2 bar) for 20 hours. ZrO2 and Ti were compared to their unaged counterparts. The materials were also compared to each other in the aged and unaged conditions. For the biological tests, the groups were also compared to a positive control of polystyrene. All tests, except roughness, were performed after the formation of salivary film on the discs. The biological tests used were Alamar Blue (n=9) to evaluate the metabolism of human gingival fibroblasts (HGF) and colony counting test (n=9) to verify the biofilm formation of a reference strain of Candida albicans (ATCC90028) on the materials. In addition, scanning electron microscopy (SEM) (n=2) was performed to evaluate the morphology of fibroblasts and microorganisms. For statistical analysis, the t-test for paired samples was used for roughness, t-test for independent samples was used for surface free energy, wettability and fibroblasts metabolism, and one-way ANOVA with Welch correction and Games-Howe... (Complete abstract click electronic access below)
Mestre
Domingos, Joana Margarida Bendada. „Acidogenic digestion of effluents of the cheese industry in packed bed biofilm reactors“. Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10648.
Der volle Inhalt der QuelleThe main goal of the present work was to study the production of volatile fatty acids (VFAs) from cheese whey powder (CWP) by employing a packed bed bioreactor (PPBR) for the anaerobic acidogenesis. First experiments were performed in 100-mL Pyrex bottles to study the acidogenesis trends, namely: lactose consumption, VFAs and biogas production and composition. These tests were done with freely suspended-cells (control experiment) and with immobilized cells using granular activated carbon (AC) and ceramic cube Vukopor S10 supports. The utilized inoculum – an acidogenic mix consortium- belongs to an analogous CWP digestion process in which a different culture system is being studied. Therefore, the incubations conditions were the same as for that culture system: 20 g/L of CWP (corresponding to 15 g/L lactose), 37ºC and pH 6. The observed trend consisted on lactose consumption, lactic acid formation (as an intermediate product) and from this VFAs production. The best yield was obtained when Vukopor was used (87% against 30% for AC); after 9 days the VFAs was (g/L): acetic (1.6), propionic (2.4); butyric (6.6) acids. The mentioned preliminary studies allowed selecting the operational hydraulic retention time(HRT) for the bioreactors. Two recirculate 1-liter PBBR one filled with Vukopor and other with AC were developed. CWP concentration, pH and temperature were the same as in the microcosm experiment. Both were operated in batch and continuous. In first batch performed in PBBR-Vuko it was achieved 6 g/L of propionic. However a loss of capability of producing it was observed during continuous operation. It was ascribed to a wash-out of related strains. With PBBR-Vuko were tested two different hydraulic retention times (HRT), 9 and 6 days, instead for PBBR-AC only HRT of 9 days. The yields for PBBRVuko were the same as at the microcosms scale, 80% for both HRT. On the other hand, the yield for PBBR-AC was 20%, this is a confirmation that AC was not the proper support even at a 1-L scale. Additionally to immobilization study, it was also set up a bioreactor with freely suspended cells. In this last mentioned bioreactor when a HRT of 6 days was set up it was observed a decrease in the VFAs yield to 44%. From this, it was concluded that the immobilization is an advantage for the VFAs production.
Brading, Melanie Gayle. „The influence of fluid dynamics and surface material on pure and binary culture biofilms“. Thesis, University of Exeter, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307314.
Der volle Inhalt der QuellePellissari, Cláudia Viviane Guimarães [UNESP]. „Biocompatibilidade de substâncias utilizadas para prevenção ou eliminação de biofilme“. Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/149226.
Der volle Inhalt der QuelleEstudos têm sido conduzidos com o intuito de prevenir a formação do biofilme em biomateriais ou buscar terapias alternativas para o tratamento de doenças decorrentes da instalação do biofilme. Como terapia alternativa, este estudo avaliou (1) a citotoxicidade da terapia fotodinâmica (PDT), através da utilização de queratinócitos humanos co-cultivados com Candida albicans. Em relação à prevenção da formação do biofilme, (2) foi avaliada a citotoxicidade de nanopartículas (NP) de tungstato de prata (Ag2WO4) e de molibdato de prata (Ag2MoO4), em solução e como revestimento de biomateriais. No estudo 1, a co-cultura foi realizada utilizando uma membrana Transwell, em que células e micro-organismos cresceram separadamente durante 24h, e ficaram em contato por mais 24h. Após este período, a PDT foi realizada utilizando-se a curcumina como fotossensibilizador. As seguintes condições foram testadas: P+ L+; P- L+; P+ L; P- L. Além disso, como controle negativo, três membranas de cada placa foram destinadas apenas ao crescimento de microorganismos e outros três poços para o crescimento de células separadamente, com seus respectivos meios. A proliferação celular, foi avaliada através dos testes Alamar Blue, MTT, XTT e UFC. Para o estudo 2, as NP foram sintetizadas e caracterizadas através de Microscopia Eletrônica de Varredura e Difração de Raios X. A partir da confecção das NP, foram feitas as soluções e o revestimento de titânio (Ti), zircônia (Zi), resina acrílica (RA) e silicone (Si). Para a realização do teste de citotoxicidade, 100 µL da suspensão composta por 1,5 x 104 células/ml (HaCat) foram colocados em cada compartimento de uma placa com 96 orifícios, incubada em estufa com 5% de CO2, a 37ºC por 24 horas. Após tal período de incubação, o meio de cultura foi desprezado, permanecendo as células aderidas no fundo da placa...(Resumo completo, clicar acesso eletrônico abaixo)
Studies have been conducted in order to prevent biofilm formation on biomaterials or seek alternative therapies for the treatment of diseases caused by biofilm installation. As an alternative therapy, this study evaluated (1) the cytotoxicity of photodynamic therapy (PDT) by the use of co-cultured human keratinocytes with Candida albicans (Ca). In relation to prevention of biofilm formation, (2) the cytotoxicity was evaluated nanoparticles (NP) silver tungstate (Ag2WO4) and silver molybdate (Ag2MoO4), in solution and as a biomaterial coating. In study 1, the co-culture was performed using a Transwell membrane, and cells in which micro-organisms grown separately for 24 h, and were in contact for a further 24h.After this period, PDT was performed using curcumin as a photosensitizer. The following conditions were tested: P+ L+; P- L+; P+ L; P- L. In addition, as a negative control, three membranes of each plate were assigned only to the growth of microorganisms and another three wells for cell growth separately with respective means. Cell proliferation was evaluated by testing the Alamar Blue, MTT, XTT, and CFU. For the study 2, the NP were synthesized and characterized by scanning electronic microscopy and X-ray diffraction. Since the making of the NP, they were made solutions and the titanium coating (Ti), zirconium (Zi), acrylic resin (RA) and silicon (Si). To perform the cytotoxicity assay, 100 µL of suspension composed of 1.5 x 104 cells / mL (HaCaT) were placed in each compartment of a plate with 96 wells, incubated in an incubator with 5% CO2 at 37 ° C for 24 hours. After this incubation period, the culture medium was discarded, remaining adhered cells at the bottom of the wells. 100 µL of culture medium containing the nanoparticles in solution and the extracts were placed on each plate hole. The plate was incubated for another 24 hours. Cell proliferation was assessed using the Alamar ... (Complete abstract electronic access below)
Pellissari, Cláudia Viviane Guimarães. „Biocompatibilidade de substâncias utilizadas para prevenção ou eliminação de biofilme /“. Araraquara, 2015. http://hdl.handle.net/11449/149226.
Der volle Inhalt der QuelleBanca: Ana Cláudia Pavarina
Banca: Nara hellen Campanha Bombarda
Resumo: Estudos têm sido conduzidos com o intuito de prevenir a formação do biofilme em biomateriais ou buscar terapias alternativas para o tratamento de doenças decorrentes da instalação do biofilme. Como terapia alternativa, este estudo avaliou (1) a citotoxicidade da terapia fotodinâmica (PDT), através da utilização de queratinócitos humanos co-cultivados com Candida albicans. Em relação à prevenção da formação do biofilme, (2) foi avaliada a citotoxicidade de nanopartículas (NP) de tungstato de prata (Ag2WO4) e de molibdato de prata (Ag2MoO4), em solução e como revestimento de biomateriais. No estudo 1, a co-cultura foi realizada utilizando uma membrana Transwell, em que células e micro-organismos cresceram separadamente durante 24h, e ficaram em contato por mais 24h. Após este período, a PDT foi realizada utilizando-se a curcumina como fotossensibilizador. As seguintes condições foram testadas: P+ L+; P- L+; P+ L; P- L. Além disso, como controle negativo, três membranas de cada placa foram destinadas apenas ao crescimento de microorganismos e outros três poços para o crescimento de células separadamente, com seus respectivos meios. A proliferação celular, foi avaliada através dos testes Alamar Blue, MTT, XTT e UFC. Para o estudo 2, as NP foram sintetizadas e caracterizadas através de Microscopia Eletrônica de Varredura e Difração de Raios X. A partir da confecção das NP, foram feitas as soluções e o revestimento de titânio (Ti), zircônia (Zi), resina acrílica (RA) e silicone (Si). Para a realização do teste de citotoxicidade, 100 µL da suspensão composta por 1,5 x 104 células/ml (HaCat) foram colocados em cada compartimento de uma placa com 96 orifícios, incubada em estufa com 5% de CO2, a 37ºC por 24 horas. Após tal período de incubação, o meio de cultura foi desprezado, permanecendo as células aderidas no fundo da placa...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Studies have been conducted in order to prevent biofilm formation on biomaterials or seek alternative therapies for the treatment of diseases caused by biofilm installation. As an alternative therapy, this study evaluated (1) the cytotoxicity of photodynamic therapy (PDT) by the use of co-cultured human keratinocytes with Candida albicans (Ca). In relation to prevention of biofilm formation, (2) the cytotoxicity was evaluated nanoparticles (NP) silver tungstate (Ag2WO4) and silver molybdate (Ag2MoO4), in solution and as a biomaterial coating. In study 1, the co-culture was performed using a Transwell membrane, and cells in which micro-organisms grown separately for 24 h, and were in contact for a further 24h.After this period, PDT was performed using curcumin as a photosensitizer. The following conditions were tested: P+ L+; P- L+; P+ L; P- L. In addition, as a negative control, three membranes of each plate were assigned only to the growth of microorganisms and another three wells for cell growth separately with respective means. Cell proliferation was evaluated by testing the Alamar Blue, MTT, XTT, and CFU. For the study 2, the NP were synthesized and characterized by scanning electronic microscopy and X-ray diffraction. Since the making of the NP, they were made solutions and the titanium coating (Ti), zirconium (Zi), acrylic resin (RA) and silicon (Si). To perform the cytotoxicity assay, 100 µL of suspension composed of 1.5 x 104 cells / mL (HaCaT) were placed in each compartment of a plate with 96 wells, incubated in an incubator with 5% CO2 at 37 ° C for 24 hours. After this incubation period, the culture medium was discarded, remaining adhered cells at the bottom of the wells. 100 µL of culture medium containing the nanoparticles in solution and the extracts were placed on each plate hole. The plate was incubated for another 24 hours. Cell proliferation was assessed using the Alamar ... (Complete abstract electronic access below)
Mestre
Balau, Bruna Filipa Mendes. „Efeito inibitório de compostos naturais em culturas planctónicas e biofilmes de Candida“. Master's thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica António Xavier, 2018. http://hdl.handle.net/10362/114989.
Der volle Inhalt der QuelleN/A
Curt, Sèverine. „Les protéines de soya, une voie d'avenir pour la régénération tissulaire“. Master's thesis, Université Laval, 2008. http://hdl.handle.net/20.500.11794/19898.
Der volle Inhalt der QuelleContreras, Lisseth Patricia Claudio. „Cerâmicas feldspáticas estratificadas e em blocos para sistema CAD/CAM : avaliação da topografia superficial, formação de biofilme inicial e viabilidade celular /“. São José dos Campos, 2017. http://hdl.handle.net/11449/148665.
Der volle Inhalt der QuelleBanca: Laís Regiane da Silva Concilio
Banca: Alexandre Luiz Souto Borges
Resumo: O objetivo deste estudo foi avaliar a topografia e a formação de biofilme na superfície de cerâmicas feldspáticas obtidas através de duas técnicas de confecção e dois tratamentos de superfície, assim como avaliar a viabilidade do crescimento de fibroblastos gengivais humanos (FMM-1) sobre estes materiais. Foram confeccionados 52 blocos de cada tipo de cerâmica feldspática: VM9 obtida através da técnica da estratificação e cerâmica Vita Blocs Mark II (VMII) para o sistema CAD/CAM (ambas, Vita Zahnfabrik). As superfícies dos blocos foram padronizadas em politriz nas dimensões de 4,5 x 4,5 x 1,5 mm e os blocos foram divididos em dois tratamentos de finalização de superfície: polimento com borrachas Ceramisté + pasta de polimento e aplicação de glaze spray + sinterização. Os parâmetros de rugosidade Ra e Rsm foram mensurados através de um rugosímetro de contato. As amostras foram esterilizadas e, em seguida contaminadas (n=10) para formação de biofilme heterotípico inicial de S. mutans, S. sanguinis e C. albicans, cuja aderência foi quantificada por contagem de unidades formadoras de colônias (UFC/mL). O teste MTT foi empregado para avaliação da viabilidade celular dos materiais ao crescimento de fibroblastos gengivais humanos (FMM-1) em 24 h e 7 dias (n=12). Foram realizadas análises qualitativas da superfície dos espécimes através de microscopia eletrônica de varredura (MEV) e perfilometria óptica 3D. A energia livre de superfície (ELS) foi calculada a partir de análises de gon... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract:The Objective of this study was to evaluate the topography and surface biofilm formation of feldspathic ceramics obtained through two techniques of preparation and two surface treatments, as well as to evaluate the viability of human gingival fibroblasts (FMM-1) growth on these materials. A total of 52 blocks of each type of feldspathic ceramic were made: VM9 obtained by the stratification technique and Vita Blocs Mark II (VMII) for the CAD/CAM system (both, Vita Zahnfabrik). The blocks' surfaces were standardized in a polishing machine to the dimensions of 4.5 x 4.5 x 1.5 mm and blocks were divided into two surface finishing treatments: polishing with Ceramisté rubbers + polishing with paste; and glaze application + sintering. The Ra and RSm roughness parameters were measured through a contact rugosimeter. Samples were sterilized and then contaminated (n = 10) for initial heterotypic biofilm formation of S. mutans, S. sanguinis and C. albicans, whose adherence was quantified by counting colony forming units (CFU/mL). The MTT test was used to evaluate the cellular viability of the materials to the growth of human gingival fibroblasts (FMM-1) in 24 h and 7 days (n=12). Qualitative analyzes of the specimens' surface were performed using a scanning electron microscopy (SEM) and 3D optical profilometry. Surface free energy (SFE) was calculated from goniometry analyzes of polar and apolar liquids in 10 samples of 15 x 15 x 1.5 mm. The results of Ra, RSm and ELS were subjected to 2-way ANOVA (Material x surface treatment) followed by Tukey's test (both, α=95%), and UFC (material x surface treatment x microorganisms) and MTT (material x surfacetreatment x time) data were evaluated by 3-way ANOVA and Tukey's test (α=95%). SEM and profilometry images were described. The polished ceramics presented lower roughness (Ra p=0.015; RSm p=0.049) ... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre
Constantin, Hervé. „La biodénitrification d'un effluent industriel fortement chargé : études cinétiques, conception d'un réacteur à lit fluidisé, et modélisation“. Vandoeuvre-les-Nancy, INPL, 1995. http://docnum.univ-lorraine.fr/public/INPL_T_1995_CONSTANTIN_H.pdf.
Der volle Inhalt der QuelleKijkla, Pruch. „Biocide Mitigation of Carbon Steel and Stainless Steel Biocorrosion by Pure-Strain and Mixed-Culture Microbial Biofilms“. Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1619007982435067.
Der volle Inhalt der QuelleContreras, Lisseth Patricia Claudio [UNESP]. „Cerâmicas feldspáticas estratificadas e em blocos para sistema CAD/CAM: avaliação da topografia superficial, formação de biofilme inicial e viabilidade celular“. Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/148665.
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O objetivo deste estudo foi avaliar a topografia e a formação de biofilme na superfície de cerâmicas feldspáticas obtidas através de duas técnicas de confecção e dois tratamentos de superfície, assim como avaliar a viabilidade do crescimento de fibroblastos gengivais humanos (FMM-1) sobre estes materiais. Foram confeccionados 52 blocos de cada tipo de cerâmica feldspática: VM9 obtida através da técnica da estratificação e cerâmica Vita Blocs Mark II (VMII) para o sistema CAD/CAM (ambas, Vita Zahnfabrik). As superfícies dos blocos foram padronizadas em politriz nas dimensões de 4,5 x 4,5 x 1,5 mm e os blocos foram divididos em dois tratamentos de finalização de superfície: polimento com borrachas Ceramisté + pasta de polimento e aplicação de glaze spray + sinterização. Os parâmetros de rugosidade Ra e Rsm foram mensurados através de um rugosímetro de contato. As amostras foram esterilizadas e, em seguida contaminadas (n=10) para formação de biofilme heterotípico inicial de S. mutans, S. sanguinis e C. albicans, cuja aderência foi quantificada por contagem de unidades formadoras de colônias (UFC/mL). O teste MTT foi empregado para avaliação da viabilidade celular dos materiais ao crescimento de fibroblastos gengivais humanos (FMM-1) em 24 h e 7 dias (n=12). Foram realizadas análises qualitativas da superfície dos espécimes através de microscopia eletrônica de varredura (MEV) e perfilometria óptica 3D. A energia livre de superfície (ELS) foi calculada a partir de análises de goniômetria com líquidos polar e apolar em 10 amostras de 15 x 1 5 x 1,5 mm. Os resultados de Ra, RSm e ELS foram submetidos à análise de variância ANOVA 2 fatores (material x tratamento de superfície) seguido por teste de Tukey (ambos, α=95%), e os dados de UFC fatores (material x tratamento x micro-organismos) e MTT (material x tratamento x tempo) foram avaliados por ANOVA 3 fatores e teste Tukey (α=95%). As imagens de MEV e perfilometria foram descritas. As cerâmicas polidas apresentaram menor rugosidade (Ra p=0,015; RSm p=0,049) e maior ELS (p=0,00), sendo que a mais alta Ra foi verificada para VM9 glazeada. A aderência bacteriana foi influenciada pela interação de todos os fatores (p=0,018). Os Streptococcus formaram em maior número em todos os materiais, mas sobre VMII polida não houve aderência de C. albicans. Inicialmente, os materiais apresentaram ausência de citotoxicidade, mas a viabilidade celular de todos os grupos foi reduzida após 7 dias (p=0,00). As micrografias mostram que a aderência de micro-organismos ocorreu independente de irregularidades na topografia dos materiais, e as imagens de perfilometria ressaltaram o padrão de ranhuras das amostras polidas e o acúmulo de glaze em “ilhas” nas amostras glazeadas. Foi possível concluir que ambas técnicas de obtenção resultam em cerâmicas feldspáticas biocompatíveis e que a finalização da superfície por polimento resultou em menor rugosidade média, maior ELS e menor aderência de C. albicans.
The objective of this study was to evaluate the topography and surface biofilm formation of feldspathic ceramics obtained through two techniques of preparation and two surface treatments, as well as to evaluate the viability of human gingival fibroblasts (FMM-1) growth on these materials. A total of 52 blocks of each type of feldspathic ceramic were made: VM9 obtained by the stratification technique and Vita Blocs Mark II (VMII) for the CAD/CAM system (both, Vita Zahnfabrik). The blocks’ surfaces were standardized in a polishing machine to the dimensions of 4.5 x 4.5 x 1.5 mm and blocks were divided into two surface finishing treatments: polishing with Ceramisté rubbers + polishing with paste; and glaze application + sintering. The Ra and RSm roughness parameters were measured through a contact rugosimeter. Samples were sterilized and then contaminated (n = 10) for initial heterotypic biofilm formation of S. mutans, S. sanguinis and C. albicans, whose adherence was quantified by counting colony forming units (CFU/mL). The MTT test was used to evaluate the cellular viability of the materials to the growth of human gingival fibroblasts (FMM-1) in 24 h and 7 days (n=12). Qualitative analyzes of the specimens’ surface were performed using a scanning electron microscopy (SEM) and 3D optical profilometry. Surface free energy (SFE) was calculated from goniometry analyzes of polar and apolar liquids in 10 samples of 15 x 15 x 1.5 mm. The results of Ra, RSm and ELS were subjected to 2-way ANOVA (Material x surface treatment) followed by Tukey’s test (both, α=95%), and UFC (material x surface treatment x microorganisms) and MTT (material x surfacetreatment x time) data were evaluated by 3-way ANOVA and Tukey’s test (α=95%). SEM and profilometry images were described. The polished ceramics presented lower roughness (Ra p=0.015; RSm p=0.049) and higher SFE (p=0.00), with the highest Ra being verified for glazed VM9. Bacterial adherence was influenced by the interaction of all factors (p=0.018). Streptococcus formed in greater number in all materials, but on polished VMII there was no adherence of C. albicans. Initially, the materials showed no cytotoxicity, but the cell viability of all groups was reduced after 7 days (p=0.00). Micrographs showed that microorganisms adherence occurred regardless of irregularities in the topography of the materials, and the profilometry images emphasized the grooved pattern of the polished samples and the glaze accumulation in "islands" in glazed samples. The surface treatments had greater influence than the technique of making the feldsphapatic ceramics. It could be concluded that both obtaining techniques resulted in biocompatible feldsphatic ceramics and that the surface finishing by polishing resulted in lower mean roughness, higher SFE and lower C. albicans adhesion.
Alquthami, Khalid. „Antibacterial effect of selenium, germanium, and lithium on clinically important bacteria growing in planktonic culture and biofilms : some medical implications“. Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/3908/.
Der volle Inhalt der QuelleEleaume, Heïdy. „Etude comparative du rôle du Quorum Sensing dans la régulation de l'expression des facteurs de virulence chez un isolat clinique de Staphylococcus Aureus en culture planctonique et en biofilm“. Littoral, 2005. http://www.theses.fr/2005DUNK0119.
Der volle Inhalt der QuelleStaphylococcus aureus is an opportunistic pathogen producing a large number of virulence factors. Among these, the secreted alpha-toxin, encoded by hla, and the surface-associated protein A, encoded by spa, are often considered as reporters of virulence factors regulation studies. The quorum sensing (QS) system, encoded by agr, is involved in their regulation in vitro. The biofilm formation ability of S. Aureus is also considered as a virulence factor, as it is the cause of heavier and chronic infections. One of the biofilm components (PIA) is synthesized by the products of the ica locus. QS involvement in the expression regulation of hla, spa and ica is studied in a clinical strain, isolated from an infected prosthesis, and in an isogenic mutant strain deleted in agrC gene, during planktonic and biofilm sessile growth. The real-time quantitative PCR technique associated with relative quantification method of target genes transcripts compared to 16S transcripts appeared to be the best method for transcription study during growth. In both growth conditions, we have demonstrated that the RNAIII transcript, the QS molecular effector, was expressed in a basal level in agrC mutant. In the same time, our study has for the first time outlined an ica activation by the QS, whereas the biofilm production by the mutant was more important. Finally, hla and spa expression regulation by QS is very different depending on growing conditions
Machado, Juliana de Carvalho. „Efeito da combinação de antibióticos e sinvastatina sobre microrganismos de interesse endodôntico e na expressão de marcadores odontoblásticos /“. Araçatuba, 2016. http://hdl.handle.net/11449/138844.
Der volle Inhalt der QuelleBanca: Ana Claudia Okamoto
Banca: Vivien Thiemy Sakai
Resumo: Terapias biológicas tem buscado novas substâncias/protocolos que promovam a eliminação microbiana e induzam ou estimulem a regeneração pulpa r e o desenvolvimento completo radicular d e dente s permanente s jove ns com processos patológicos pulpares. Os objetivos do estudo foram avaliar a a tividade antimicrobiana /antibiofilme de algumas combinações de antibióticos sobre microrganismos de interesse endodôntico e analisar o efeito da combinação de antibióticos com melhor ação antimicrobiana associada à sinvastatina na expressão de marcadores o dontoblásticos em células da polpa dental humana (CPDH) . A atividade antimicrobiana dos seguintes antibióticos : Metronidazol (ME), C iprofloxacina (CI), Minociclina (MI), Doxicilina (DO) e F osfomicina (FO), isolados ou em combinação dupla (ME+CI, ME+MI, ME+DO, ME+FO, CI+MI, CI+DO, CI+FO, DO+FO, MI+FO) ou tripla (ME+CI+MI, ME+CI+FO, ME+MI+FO, ME+CI+DO, ME+DO+FO, CI+DO+FO, CI+MI+FO) foram testados contra Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii e Candida albicans em condições planctônicas. Biofilmes mono - espécie de E. faecalis e biofilmes em dual - espécies de E. faecalis and C. albicans fora m prepara dos em bloc os de dentina para testar a atividade anti biofilme das combinações de antibióticos com os melhores result ados microbiológicos. O efeito antibiofilme das combinações antibióticas sobre biofilme de E. faecalis dentro dos túbulos dentinários foi também avaliada por microscopia confocal. Culturas de CPDH foram expostas à combinação antibiótica com melhor resultad o microbiol ógico e sinvastatina e determinada a viabilidade celular, atividade da f osfatase alcalina (ALP), deposição de nódulos de mineralização e expressão de DSPP (sialofosfoproteína dentinária), importante marcador odontoblástico...
Abstract: Biological therapies have searching for substances/protocols, which promote microbial elimination and induce or sti mulate pulp regeneration and completion of apical root development in young perm anent teeth wi th pulp pa thological processes . The objective s of this study were to evaluate the anti microbial /anti - biofilm activity of some antibiotics combinations on endodontic microorgan isms and the effect of the combina tion of anti biotics with the best anti microbial action associated with simvastatin on expression of odontoblast markers by human dental pulp cells (HDPC) . The antimicrobial activity of the following antibiotics : Metronidazole ( ME ), Ciprofloxacin ( CI), Minocycline (MI), Doxycycline (DO) and Fosfomycin ( FO), either alone or in double (ME+CI, ME+MI, ME+DO, ME+FO, CI+MI, CI+DO, CI+FO, DO+FO, MI+FO) or triple combinations (ME+CI+MI, ME+CI+FO, ME+MI+FO, ME+CI+DO, ME+DO+FO, CI+DO+FO, CI+MI+FO ) were tested against Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii and Candida albicans in planktonic conditions . Mono - species biofilm of E. faecalis and dual - species biofilms of E. faecalis and C. albicans were prepared in dentin blocks to test the anti - biofilm activity of antibiotic combi nations with the best microbiolo gical results . Antibiofilm effect of antibiotic combination on E. faecalis biofilm inside dentin tubules was also evaluated by confocal microscopy . Culture s of HDPC were exposed to the antibiotic combination with the best antimicrobial effect and simvastatin and determined cell viability, alkaline phosphatase activity, deposition of mineralization nodules and expression of Dspp (dentin sialophosphoprotein), important odontoblast markers of dentin mineralization. Data were analyzed statistically, considering p<0.05 . All antibiotic combina tions reduced statistically the growth of bacteria...
Mestre
Ribeiro, Ana Paula Dias [UNESP]. „Efeito da terapia fotodinâmica antimicrobiana sobre culturas planctônicas e biofilmes de bactérias e fungos utilizando curcumina e cloro-alumínio ftalocianina veiculada por nanoemulsões“. Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/105501.
Der volle Inhalt der QuelleCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Esta investigação teve os seguintes objetivos: 1. avaliar in vitro o efeito da Terapia Fotodinâmica (PDT) utilizando diferentes concentrações de curcumina e doses de luz LED na inativação de suspensões planctônicas de S. aureus resistente (MRSA) e susceptível à meticilina (MSSA) e a citotoxicidade dos parâmetros antimicrobianos dessa terapia em cultura celular de fibroblastos; 2. o efeito fotodinâmico da cloro-alumínio ftalocianina (ClAlFt) veiculada em nano-emulsão catiônica e aniônica e comparar com ClAlFt diluída em solvente orgânico na inativação da C. albicans quando em suspensão planctônica e organizados em biofilmes; 3. o efeito antimicrobiano da terapia fotodinâmica utilizando a cloroalumínio ftalocianina em sistema de nanoemulsão em culturas planctônicas e biofilmes de bactérias gram-positivas (MSSA e MRSA). No primeiro estudo, suspensões de MSSA e MRSA foram tratadas com diferentes concentrações de curcumina (entre 0,1 a 20,0 μM) e expostas a diferentes fluências de LED azul (18; 25 e 37,5 J/cm2). Em seguida, diluições seriadas foram obtidas e alíquotas de 25 μl de cada diluição foram plaqueadas em meio de cultura Mannitol Salt Agar. Após o período de incubação de 48 horas a 37°C, as unidades formadoras de colônias foram determinadas (UFC/mL). Para as células L929, essas foram incubadas por 20 minutos com curcumina e irradiadas em seguida com LED (37,5 J/cm2). A viabilidade celular após a PDT foi avaliada utilizando o teste de MTT e as alterações morfológicas foram avaliadas pela microscopia eletrônica de varredura (MEV). Os resultados foram submetidos à análise descritiva, Análise de Variância (ANOVA) e post hoc de Tukey (α= 5%). As concentrações de 5, 10 e 20 μM resultaram em completa inativação do MSSA quando associadas a qualquer fluência de energia...
The aim of this investigation was to evaluate: 1. the Photodynamic Therapy (PDT) mediated by curcumin for in vitro inactivation of methicillin-resistant S. aureus (MRSA) and susceptible S. aureus (MSSA) and its citotoxic effects against L929 fibroblasts; 2. the photodynamic potential of aluminum-chloride-phthalocyanine (ClAlPc) entrapped in cationic and anionic nanoemulsions (NE) to inactivate C. albicans planktonic and biofilm cultures compared with free ClAlPc; 3. the photodynamic effect of ClAlPc encapsulated in NE on methicillin susceptible and resistant S. aureus suspensions and biofilms. In the first study, suspensions of MSSA and MRSA were treated with different concentrations of curcumin and exposed to LED. Serial dilutions were obtained from each sample, and colony counts were quantified. For fibroblasts, the cell viability subsequent to the curcumin-mediated photodynamic therapy was evaluated using the MTT assay and morphological changes were assessed by SEM analysis. Curcumin concentrations ranging from 5.0 to 20.0 μM in combination with any tested LED fluences resulted in photokilling of MSSA. However, only the 20.0 μM concentration in combination with highest fluence resulted in photokilling of MRSA. This combination also promoted an 80% reduction in fibroblast cell metabolism and morphological changes were present, indicating that cell membrane was the main target of this phototherapy. In the second study, fungal suspensions were treated with different types of delivery systems containing ClAlPc. After 30 minutes, the drug was washed-out and samples were illuminated with LED source (660 ± 3 nm). Negative control samples were not exposed to ClAlPc or light. For planktonic suspensions, colonies were counted (CFU/ml) and cell metabolism was evaluated by XTT assay. (Kruskal-Wallis and... (Complete abstract click electronic access below)
Ribeiro, Ana Paula Dias. „Efeito da terapia fotodinâmica antimicrobiana sobre culturas planctônicas e biofilmes de bactérias e fungos utilizando curcumina e cloro-alumínio ftalocianina veiculada por nanoemulsões /“. Araraquara : [s.n.], 2012. http://hdl.handle.net/11449/105501.
Der volle Inhalt der QuelleBanca: Ana Lúcia Machado
Banca: Francisco de Assis Nollo Junior
Banca: Helena de Freitas Oliveira Paranhos
Banca: Soraya Coelho Leal
Resumo: Esta investigação teve os seguintes objetivos: 1. avaliar in vitro o efeito da Terapia Fotodinâmica (PDT) utilizando diferentes concentrações de curcumina e doses de luz LED na inativação de suspensões planctônicas de S. aureus resistente (MRSA) e susceptível à meticilina (MSSA) e a citotoxicidade dos parâmetros antimicrobianos dessa terapia em cultura celular de fibroblastos; 2. o efeito fotodinâmico da cloro-alumínio ftalocianina (ClAlFt) veiculada em nano-emulsão catiônica e aniônica e comparar com ClAlFt diluída em solvente orgânico na inativação da C. albicans quando em suspensão planctônica e organizados em biofilmes; 3. o efeito antimicrobiano da terapia fotodinâmica utilizando a cloroalumínio ftalocianina em sistema de nanoemulsão em culturas planctônicas e biofilmes de bactérias gram-positivas (MSSA e MRSA). No primeiro estudo, suspensões de MSSA e MRSA foram tratadas com diferentes concentrações de curcumina (entre 0,1 a 20,0 μM) e expostas a diferentes fluências de LED azul (18; 25 e 37,5 J/cm2). Em seguida, diluições seriadas foram obtidas e alíquotas de 25 μl de cada diluição foram plaqueadas em meio de cultura Mannitol Salt Agar. Após o período de incubação de 48 horas a 37°C, as unidades formadoras de colônias foram determinadas (UFC/mL). Para as células L929, essas foram incubadas por 20 minutos com curcumina e irradiadas em seguida com LED (37,5 J/cm2). A viabilidade celular após a PDT foi avaliada utilizando o teste de MTT e as alterações morfológicas foram avaliadas pela microscopia eletrônica de varredura (MEV). Os resultados foram submetidos à análise descritiva, Análise de Variância (ANOVA) e post hoc de Tukey (α= 5%). As concentrações de 5, 10 e 20 μM resultaram em completa inativação do MSSA quando associadas a qualquer fluência de energia... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this investigation was to evaluate: 1. the Photodynamic Therapy (PDT) mediated by curcumin for in vitro inactivation of methicillin-resistant S. aureus (MRSA) and susceptible S. aureus (MSSA) and its citotoxic effects against L929 fibroblasts; 2. the photodynamic potential of aluminum-chloride-phthalocyanine (ClAlPc) entrapped in cationic and anionic nanoemulsions (NE) to inactivate C. albicans planktonic and biofilm cultures compared with free ClAlPc; 3. the photodynamic effect of ClAlPc encapsulated in NE on methicillin susceptible and resistant S. aureus suspensions and biofilms. In the first study, suspensions of MSSA and MRSA were treated with different concentrations of curcumin and exposed to LED. Serial dilutions were obtained from each sample, and colony counts were quantified. For fibroblasts, the cell viability subsequent to the curcumin-mediated photodynamic therapy was evaluated using the MTT assay and morphological changes were assessed by SEM analysis. Curcumin concentrations ranging from 5.0 to 20.0 μM in combination with any tested LED fluences resulted in photokilling of MSSA. However, only the 20.0 μM concentration in combination with highest fluence resulted in photokilling of MRSA. This combination also promoted an 80% reduction in fibroblast cell metabolism and morphological changes were present, indicating that cell membrane was the main target of this phototherapy. In the second study, fungal suspensions were treated with different types of delivery systems containing ClAlPc. After 30 minutes, the drug was washed-out and samples were illuminated with LED source (660 ± 3 nm). Negative control samples were not exposed to ClAlPc or light. For planktonic suspensions, colonies were counted (CFU/ml) and cell metabolism was evaluated by XTT assay. (Kruskal-Wallis and... (Complete abstract click electronic access below)
Doutor
Juntke, Jenny [Verfasser], und Claus-Michael [Akademischer Betreuer] Lehr. „A novel co-culture model of human bronchial epithelial cells and Pseudomonas aeruginosa biofilms to mimic chronic lung infections in cystic fibrosis / Jenny Juntke ; Betreuer: Claus-Michael Lehr“. Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2018. http://d-nb.info/1183673698/34.
Der volle Inhalt der QuelleCosta, Andréa Bernardes Vilhena. „Padronização da reação de Immuno-dot para detecção de Pet em sobrenadante de cultura de Escherichia coli enteroagregativa“. Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-31082009-163535/.
Der volle Inhalt der QuelleEnteroaggregative Escherichia coli (EAggEC) is an emerging diarrheal pathogen, whose pathogenesis is thought to comprise colonization of the intestinal mucosa with the release of secretogenic toxins. One of the toxin involved is the plasmid-encoded toxin (Pet), which is secreted by the autotransporter mechanism and belongs to a growing class of Enterobacteriaceae autotransporter proteins. Since the characteristic aggregative adherence pattern of EAggEC is associated with the presence of a large plasmid called pCVD432, DNA probes and PCR primers derived from this plasmid have been recommended as a screening method for EAggEC in the clinicai laboratory. In this study 164 E. coli isolates positive for the pCVD432 probe were tested for adherence to HEp-2 cells in which 141 isolates showed aggregative pattern, 12 isolates from them amplify a 1037-bp DNA fragment corresponding to pet gene by PCR. Using this samples we standardized an immuno-dot assay for EAggEC detection through Pet toxin as target antigen. 300 µl of bacterial supernatant were applied in a PVDF membrane, and using a rabbit polyclonal sera anti-Pet the expression of the toxin by immuno-dot was in the same isolates in which the gene was detected. Besides no negative controls reacted with Pet antisera, in which we included 40 isolates with no virulence markers for diarrheagenic E. coli and E. coli expressing toxins other than Pet. This method proves to be rapid, sensitive, specific and low cost, demonstrating this potential as diagnosis for Pet expression and its association with diarrhea.
Robins, Jeffrey P. „Attachment and early biofilm development of methane-forming anaerobic microbial cultures“. 1988. https://scholarworks.umass.edu/dissertations/AAI8813271.
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