Dissertations / Theses: 'Bacteria; Bone'

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Linton, Kathryn Mary. "Calcium phosphate morphology in bone and bacteria." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445383.

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Clasper, Jonathan C. "External fixator pin tract infection." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365816.

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Gbejuade, Herbert Olukayode. "The effects of antibiotic loaded bone cement combinations on bacteria biofilms." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705469.

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Airila-Månsson, Stella. "Progression of periodontitis and influence of periodontal bacteria on release of inflammatory markers in Swedish adults /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-622-0/.

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Pacios, Pujadó Sandra. "Cellular Mechanisms that affect Periodontal Destruction induced by Bacteria Infection in Diabetic and Non Diabetic Rats." Doctoral thesis, Universitat Internacional de Catalunya, 2014. http://hdl.handle.net/10803/275965.

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The aim of this study was to evaluate the histologic and cellular response to A.actinomycetemcomitans (A.a) infection, and how diabetes-enhanced TNF-α production and diabetes-enhanced apoptosis contribute to the periodontal disease progression and bone coupling. Conclusion. The results link A. a infection with important characteristics of periodontal destruction and provide new insight into how diabetes aggravates A. a induced periodontal destruction in rats by significantly increasing the inflammatory response, leading to increased bone loss and enhancing apoptosis of gingival epithelial and connective tissue cells through a caspase-3-dependent mechanism. Antibiotics had a more pronounced effect on many of these parameters in diabetic than in normoglycemic rats, suggesting a deficiency in the capacity of diabetic animals to resist infection. In addition, diabetes prolongs inflammation and osteoclastogenesis in periodontitis and through TNF limits the normal reparative process by negatively modulating factors that regulate bone. El objetivo de este estudio fue evaluar la respuesta histológica y celular a la infección por A.actinomycetemcomitans (A.a) y como la diabetes exacerba la producción de TNF- α y la apoptosis que contribuye a la progresión de la enfermedad periodontal y al acoplamiento del hueso. Los resultados enlazan la infección de A. a con características importantes de destrucción periodontal y ofrece una nueva visión de cómo la diabetes agrava la destrucción periodontal con A. a mediante un aumento significativo de la respuesta inflamatoria, lo que lleva al aumento de pérdida ósea y produce un aumento de apoptosis en el epitelio gingival y en las células del tejido conectivo a través de un mecanismo de caspasa-3 dependiente. Los antibióticos tuvieron un efecto más pronunciado en mucho de los parámetros evaluados en las ratas diabéticas que en las normoglucémicas, sugiriendo una deficiencia en la capacidad de los animales diabéticos en combatir la infección. Además la diabetes prolonga la inflamación y la osteoclastogénesis en la periodontitis y a través de TNF limita el proceso normal de reparación modulando negativamente factores que regulan el hueso.

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Rogers, Christopher. "Dating death : forensic taphonomy and the postmortem interval." Thesis, University of Wolverhampton, 2010. http://hdl.handle.net/2436/210852.

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Determining the postmortem interval (PMI) remains one of the most important but challenging factors to establish in a suspicious death investigation. Unfortunately, as time passes current methods lose accuracy and only allow investigators to approximate how long ago death occurred. Bodies interred in clandestine graves prove particularly challenging due to an abundance of variables that need to be taken into consideration. Due to the problems associated with determining the PMI of buried remains this study will utilise macroscopic, microscopic, molecular, chemical and microbiological analyses to systematically document the decompositional changes to human hair and porcine cartilage and bone in a burial environment. The aim was to correlate decompositional changes with time and develop new methods for estimating the PMI of remains found in this context. Whole trotters (from which the cartilage was harvested) exhibited decompositional changes including darkening of the dermis, skin slippage, liquefaction of soft tissues and complete skeletonisation. The decompositional changes to cartilage included a loss of cartilage covering articular facets, changes in colour and texture, formation of orthorhombic crystals, a change in surface pH and colonisation by bacteria. The bacteria found on the cartilage surface were in close proximity to the crystals and when cultured on a B-41 medium were found to precipitate crystals of the same morphology and chemical composition to those found on the cartilage surface. Three species of bacteria (Acinetobacter calcoaceticus, Acinetobacter iwoffii and Grimontia hollisae) were identified based on gas chromatography–mass spectrometry (GC-MS) of their fatty acids and one species (Comamonas sp.) was identified by DNA analysis. Formation of crystals on goat and cow cartilage proved that this was not a porcine specific phenomenon. Human hair exhibited a gradual degradation over time but this was dependent on the characteristics of the burial environment. Decompositional changes included colonisation by fungi, erosions to the cortical surface and formation of tunnels and breaks to the hair shaft. Two fungal species (Aspergillus fumigatus and Penicillium sp.) were identified based on DNA analysis of fungal ribosomal (rDNA) internally transcribed spacer (ITS) regions. The Penicillium sp. was linked with fungal tunnelling of hair. Bone exhibited little modification over time but changes were observed. These included a change in colour of the cortical surface, a change in colour and gradual loss of bone marrow and erosions, cracking and flaking of the cortical bone. Fungi were found to colonise both the bone marrow and bone surface. Whole piglets were buried to document the time period taken to reach skeletonisation. This data was used as a correction factor and combined with the bone results to give an overall time period for the decomposition changes observed. The results of this study suggest that the decompositional changes to cartilage could be used to determine the postmortem interval of buried remains. However, the degradation of hair and bone was too variable to be of use in this context.

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King, Janice E. "Carbon-sulfur bond cleavage by environmental bacteria." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318772.

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Kanso, Sungwan, and n/a. "Molecular Studies of Bacterial Communities in the Great Artesian Basin Aquifers." Griffith University. School of Biomolecular and Biomedical Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040219.140509.

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16S rRNA gene analysis has shown that bacterial diversity in the GAB bores studied was limited to the genera Hydrogenobacter in the phylum Aquificae, Thermus in the phylum Deinococcus-Thermus, Desulfotomaculum in the phylum Firmicutes, the alpha-, beta- and gamma-classes of the phylum Proteobacteria and the phylum Nitrospirae. There was no clone closely related to members of the delta-proteobacteria and epsilon-proteobacteria classes detected. The number of bacterial strains directly isolated from the Fairlea and the Cooinda bores were far less than the numbers of distinctive phylotypes detected by the 16S rRNA gene characterisation. In addition none of the bacterial strains directly isolated from the water samples were represented in the 16S rRNA gene clone libraries. Similar discrepancies between the bacterial populations obtained from the 16S rRNA gene analysis and those obtained from direct isolation have been reported in the literature (Dunbar et al., 1999; Kampfer et al., 1996; Suzuki et al., 1997; Ward et al., 1998; Ward et al., 1997). However, in general, the phyla with which the isolates were affiliated were the same as those phyla to which the clones belonged. The environmental changes introduced (by bringing the artesian water up to the surface and exposing it to four types of metal coupons made of carbon steels identified by codes ASTM-A53B, ASTM-A53, AS-1074 and AS-1396 and commonly used in bore casings) led to changes in the bacterial community structures. In general, the species which proliferated in the communities before and after the changes were different. The diversity of the bacterial species in the community decreased following the environmental changes. Clones dominating the clone libraries constructed from newly established bacterial communities also differed from the clones dominating the libraries constructed from the bacterial communities which had existed naturally in the bores. These trends toward change in the bacterial communities were observed at both the Fairlea and the Cooinda bore sites. All four metal types incubated in the Fairlea bore water lost between 3.4 and 4.7% of their original weight. In contrast none of the metals incubated in Cooinda bore water lost weight. Clone library A1 showed that the natural population of the Fairlea bore was dominated by clone A1-3, which represented a novel species related to the isolate boom-7m-04. But after metal incubation (and recording of the metal weight loss), the bacterial community was dominated by clone PKA34B, which has a 95% similarity in its 16S rRNA gene sequence with Desulfotomaculum putei. Desulfotomaculum species are known to cause metal corrosion due to their byproduct H2S. But the low level of phylogenetic relatedness found does not provide enough information to speculate on whether the species represented by clone PKA34B is a member of the genus Desulfotomaculum or not. However, the fact that clone PKA34B dominated the PKA clone library by 50% makes the species it represents a suspected candidate likely to be involved with the metal weight loss at the Fairlea bore. In contrast, clone library 4381 showed that the natural population of the Cooinda bore was dominated by clone 4381-15 representing a species distantly related to a hydrogen oxidiser Hydrogenophaga flava (95% similarity). The dominating clone of the new community formed after metal incubation was clone COO25, which has 99% similarity with Thermus species that have not been reported to be involved with metal corrosion to my knowledge. In this project detection, identification and comparative quantification by 16S rRNA gene-targeted PCR probing with probes 23B and 34B were successfully developed for a Leptothrix-like species and for a Desulfotomaculum-like species represented by clones PKA23B and PKA34B respectively. This method of probing permits a fast, sensitive and reproducible detection, identification and at least a comparative quantification of the bacteria in the environment without the need for culturing. Therefore it is extremely suitable for use in bacterial population monitoring. PCR probing with the 34B probe has a potential commercial use as a means of screening for bores with a potential high risk of corrosion due to this Desulfotomaculum-like species. Direct isolation of bacteria from the GAB water has resulted in the isolation of seven strains from the Fairlea bore and eight from the Cooinda bore. Among these isolates, three novel strains were studied in detail. Reports on the characterisation of strain FaiI4T (T=Type strain) from the Fairlea bore (Kanso & Patel, 2003) and strain CooI3BT from the Cooinda bore have been published (Kanso et al., 2002). The data generated during this project add to our current information and extend our knowledge about the bacterial communities of the GAB's sub-surface environment. This information will provide a basis for further ecological studies of the GAB. Studies on involvement of certain groups of bacteria with the corrosion of metals used in bore casings could provide a foundation for further studies to develop maintenance and managing strategies for the GAB bores.

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Skepu, Zoleka G. "Characterization of amide bond hydrolysis in novel hydantoinase-producing bacteria." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1003970.

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This thesis describes a series of investigations into the amide bond-hydrolyzing activity of bacterial strains RU-KM1, RU-KM3L, RU-KM3S, and RU-OR, which were previously isolated for their ability to hydrolyze hydantoins to amino acids. The main aim of the study was to develop biotransformations with potential application in the production of enantiomerically pure amino acids and related compounds. Several compounds may be used as substrates by biocatalysts for the production of amino acids, such as hydantoins, amino nitriles, and amides. These compounds are not only important for amino acid production, but they may be used for production of other industrially important compounds, such as 2- arylpropionic acids, which are non-steroidal anti-inflammatory drugs. Thus, the ability of the above-mentioned strains to hydrolyze these substrates was investigated, with the view to utilizing the maximum potential of these biocatalysts. The compounds used as substrates in the investigation are all essentially amides. Thus, the ability of the strains to hydrolyze imides, hydantoins, and amides, was investigated. In particular, imides have a structure which is very similar to that of hydantoins, and thus it was an objective of the study to determine whether these strains could hydrolyze imides. Imidehydrolyzing activity has only recently been discovered in microorganisms. Hydantoin conversion involves a two-step hydrolysis reaction which yields, initially, an Ncarbamylamino acid intermediate, and subsequently, an "-amino acid. The hydantoinhydrolyzing enzymes of a Pseudomonas putida strain, RU-KM3S, were characterized in a crude extract preparation and reaction conditions for its biocatalytic application were optimized. The optimum conditions for conversion of 5-methylhydantoin were found to be 3 hours at 40°C, with conversion yields greater than 50% achieved. The enzymes of RU-KM3S demonstrated considerable stability, retaining 80% of their activity after incubation at 40°C for 3 hours. The activities of the enzymes were increased by the addition of a detergent to the extraction medium, suggesting that the enzymes might be membrane-bound. The results of the determination of the metal-dependence of the hydantoinase and N-carbamylase of RUKM3S suggested that these enzymes required metal ions for activity, with metal ions such as Mg²⁺, Mn²⁺, Zn²⁺, and Co²⁺ resulting in activation of the enzymes. However, Cu²⁺ and Fe²⁺ caused inactivation of these enzymes. The stereoselectivity of the enzymes was investigated, and the results suggested that the hydantoinase was non-selective, whereas the N-carbamylase was L-selective. The hydantoin substrate selectivity of RU-KM3S was compared to that of three other hydantoinase-producing bacteria, RU-KM1, RU-KM3L, and RU-OR. The four strains were able to hydrolyze all of the seven substrates tested. However, there was a difference in activity levels between crude extract preparations and whole cells, with crude extracts generally showing higher activity than whole cells, except in the case of RU-KM1. Some difference was also observed in the order of preference of substrates between whole cells and crude extracts. The preferred substrate for RU-KM1 whole cells was isopropylhydantoin, whereas the crude extract preparation preferentially hydrolyzed p-hydroxyphenylhydantoin. RU-KM3L whole cells achieved a higher conversion yield with isobutylhydantoin, whereas the crude extract achieved a higher yield with 5-t-butylhydantoin. RU-KM3S whole cells and crude extract preferentially hydrolyzed 5-n-butylhydantoin, although the yield was greater with the crude extract. The highest conversion yields were observed with RU-KM3S crude extract, with conversion yields of 71.6% and 100% for n-butylhydantoin and phydroxyphenylhydantoin, respectively.The ability of RU-KM1, RU-KM3L, and RU-KM3S to hydrolyze nitriles, initially to amides and subsequently to carboxylic acids, was investigated. These strains were demonstrated to be unable to utilize acrylonitrile, propionitrile and benzonitrile as nitrogen sources, but were able to hydrolyze acrylonitrile, propionitrile and acetonitrile, in resting cell reactions. Nitrile hydrolysis was demonstrated to be inducible in all three strains, and the enzyme system responsible for nitrile hydrolysis was proposed to be a nitrile hydratase-amidase system. Amidase activity in the four bacterial strains was investigated. The ability of RU-KM1, RUKM3L, RU-KM3S, and RU-OR to utilize amides as a nitrogen source was investigated, and the results showed that propionamide was a good nitrogen source for all four of the strains. Amide-hydrolyzing activity, by resting cells, was shown to be inducible by propionamide in all four strains. RU-KM3S demonstrated superior amide-hydrolyzing ability in that it hydrolyzed propionamide, acetamide, and acrylamide to a greater extent than the other strains. Resting cells of RU-KM1 and RU-OR were demonstrated to have the ability to hydrolyze the imide substrate, succinimide, and this imidase activity was found to be inducible. These strains were also able to utilize this imide as the sole source of nitrogen for growth, which is a novel finding, as to date, bacteria have only be reported to utilize imides as a carbon source. The identity of the enzyme system responsible for succinimide hydrolysis is not yet clear. In conclusion, the hydantoin-hydrolyzing enzymes of RU-KM3S have been shown to be possibly membrane associated, which is a novel finding that has also been proposed in three other hydantoinase-producing strains in our laboratory. This study has shown that the Ncarbamylase of RU-KM3S is L-stereoselective, which, to our knowledge, is the first report of an L-stereospecific N-carbamylase in a Pseudomonas putida. Publication of these findings is already in progress. This is the first report on the study of imide hydrolysis in either an Agrobacterium tumefaciens or a Pseudomonas sp., and publications reporting these results are in preparation.

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O'Brien, Andrea C. "Cold active antimicrobial compounds from Antarctic microorganisms." Thesis, London South Bank University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288169.

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Retief, Liezl. "Molecular detection and characterisation of potentially zoonotic bacteria in bathyergids from the Western Cape Province." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/67139.

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Globally emphasis has been given to identify emerging and re-emerging pathogens. Rapid urban expansion creates a problem which is two-fold. Firstly, increasing slum living conditions due to inadequate rate of infrastructure development results in an increased reliance on natural resources, including the capture and consumption of surrounding wildlife to subsist, thereby facilitating the transfer of emergent zoonotic pathogens. Secondly, through activities such as pollution or alien species introductions, the rapid transformation of once pristine environments, alters natural systems, potentially exposing these environments to new bacterial pathogens. Therefore, the main aim of this study was to assess overlooked bacterial species harboured by four host species (Bathyergus suillus, Georychus capensis, Cryptomys hottentotus hottentotus and Fukomys damarensis) belonging to the subterranean rodent family Bathyergidae, which inhabit an environment well-suited for an array of bacterial species, and which varied in their exposure to human settlements. Bacterial prevalence and diversity was initially evaluated using broad-range PCR techniques in combination with nucleotide sequencing. This revealed high levels of bacterial prevalence (82.91%) and mixed infections (22.60%) in bathyergid species. Two bacterial groups, the Bacillus cereus complex (a group of soil-dwelling bacterial strains with pathogenic potential with an overall prevalence of 8.55%) and haemotropic Mycoplasma strains (vector-borne bacterial strains of zoonotic potential with an overall prevalence of 1.28%) were subsequently selected for further genetic analysis with genus and species-specific PCRs. Bacillus molecular screening and phylogenetic analyses was achieved by targeting four gene regions with seven published primer assays and two novel PCR assays. This enabled identification of two B. cereus complex strains in bathyergid lungs and revealed an overall B. cereus complex prevalence of 17.95% for the 234 bathyergid lung samples screened. Bacillus genome prevalence was significantly higher in B. suillus individuals (45.35%), sampled in a peri-urban environment, compared to the other bathyergid species sampled from pristine habitats (ranging from 0% - 4.44%). Anthropogenic activities in the area where B. suillus was sampled could, at least partially, attribute to the perceived difference between urban and naturally sampled bathyergid species, highlighting the role of B. suillus to act as both a reservoir of potentially zoonotic pathogens and as a sentinel for anthropogenic soiling. Mycoplasma molecular screening using three different PCR assays, all targeting the 16S rRNA gene region, confirmed an overall haemotropic Mycoplasma prevalence of 24.13% in the 286 bathyergid organs (lung, spleen and liver) screened. A significantly higher prevalence and diversity of haemotropic Mycoplasma strains was found in B. suillus lungs (41.86%) compared to its naturally occurring relatives (ranging from 0%-36%). Phylogenetic analyses identified six novel haemotropic Mycoplasma strains, all grouping within a discrete monophyletic cluster, sister to Mycoplasma coccoides, and comprising two well-supported sub-clusters. The human introduction of commensal rodents harbouring Mycoplasma strains transferred through cosmopolitan arthropod vectors to indigenous bathyergids, likely underlies the higher prevalence in urban areas, although other biotic and abiotic factors affecting ectoparasite load also merit consideration. The data generated by the current study indicate the need to identify largely overlooked and potentially zoonotic bacterial pathogens in subterranean mammals and emphasises the importance of monitoring anthropogenically-introduced, opportunistic pathogens and the threats they pose to vulnerable communities and co-occurring, free-living animal species Dissertation (MSc)--University of Pretoria, 2017. Airports Company of South Africa (ACSA) National Research Foundation (NRF) Zoology and Entomology MSc Unrestricted

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Prates, Talita Pereira. "Papel dos receptores tipo NOD na modulação da reabsorção óssea em modelo de periodontite experimental." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/58/58135/tde-02022015-105829/.

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O biofilme bacteriano é o agente etiológico primário no desenvolvimento da resposta inflamatória observada na doença periodontal. Os receptores do tipo NOD (NLRs) são proteínas citosólicas que reconhecem componentes microbianos presentes no citoplasma liberados por bactérias invasoras. Sabendo que bactérias periodontopatogênicas têm a capacidade de invadir e colonizar diversas células do tecido periodontal, o presente projeto tem o objetivo de estudar a participação dos receptores do tipo NOD (NOD1 e NOD2) no reconhecimento das bactérias Porphyromonas gingivalis, na modulação da resposta imune e no processo de reabsorção óssea. Camundongos isogênicos machos da linhagem C57BL/6 (WT) e camundongos deficientes para o receptor NOD1 (NOD1-/-) e receptor NOD2 (NOD2-/-) foram infectados com Phorphyromonas gingivalis utilizando um modelo experimental de doença periodontal. O grau de reabsorção óssea foi avaliado por análise morfométrica macroscópica e histológica da maxila, além da quantificação do número de osteoclastos na crista óssea alveolar. O grau de inflamação local foi realizado por contagem do número total de bactérias orais, quantificação de neutrófilos no tecido gengival (MPO) e avaliação dos mediadores inflamatórios por ELISA. Foi também avaliada a expressão de marcadores osteogênicos e osteoclastogênicos no tecido gengival pela técnica de qPCR. Animais NOD1-/- e NOD2-/- apresentaram menor delta de reabsorção óssea quando comparados aos animais WT. Animais NOD2-/- infectados apresentaram debilitado controle bacteriano quando comparados aos animais WT infectados. Animais NOD1-/- e NOD2-/- infectados apresentaram baixa expressão de Cxcl1 e MPO quando comparados aos animais WT infectados. Além disso, foi observado que animais NOD2-/- infectados apresentaram reduzida produção de TNF-α e elevada produção de IL-10 quando comparados aos animais WT infectados. Não foi detectado diferença estatística na expressão de fatores osteogênicos, Runx2 e osteocalcina, entre animais WT, NOD1-/- e NOD2-/- infectados. Embora não houve diferença no número de células TRAP positivas presentes na crista óssea alveolar entre os grupos no tempo avaliado, animais WT infectados apresentaram elevada expressão gênica de RANKL/OPG quando comparados aos animais NOD2-/- infectados. Além disso, a expressão de marcadores de atividades dos osteoclastos, catepsina k e matrix metaloproteinase-9, foi significantemente baixa nos animais NOD1-/- e NOD2-/- infectados quando comparados aos animais WT infectados. Esses resultados permitem sugerir que independente das variáveis observadas, verificamos que a ausência dos dois receptores impede a rápida progressão da reabsorção óssea alveolar observada na periodontite, portanto os receptores NOD1 e NOD2 contribuem para progressão da reabsorção óssea no modelo experimental de periodontite. The bacterial biofilm has been identified as an etiological agent in the pathogenesis of periodontal disease. The NOD-like receptors (NLRs) are cytoplasmic proteins that sense microbial by products released by invasive bacteria. Since periodontopathogenic bacteria are able to invade and colonize some periodontal tissue cells, the purpose of this study is to determine the role of NOD1 and NOD2 receptors in the recognition of invasive periodontopathogenic bacteria such as Porphyromonas gingivalis, modulating the immune response and bone resorption. Isogenic strain C57BL/6 males (WT), NOD1 (NOD1-/-) and NOD2 (NOD2-/-) knockout mice were infected with Porphyromonas gingivalis in an experimental model of periodontal disease. Alveolar bone resorption was evaluated by macroscopic and histological morphometric analysis, quantification of osteoclasts numbers in bone crest alveolar. Imune inflammatory response was evaluated by, bacterial load, neutrophils quantification and inflammatory mediators levels by ELISA. We also evaluated the osteogenic and osteoclastogenic markers expression in gingival tissue by Real time PCR techniques. NOD1-/- and NOD2-/- animals showed lower bone resorption when compared to WT animals. NOD2-/- infected animals expressed higher bacterial load compared to WT infected ones. NOD1-/- and NOD2-/- infected animals presented lower Cxcl1 and MPO levels compared to WT infected animals. In addition, NOD2-/- infected animals presented lower level of TNF-α and higher level of IL-10 when compared to WT infected animals. There was no significant difference in the osteogenic factors expression, Runx2 and osteocalcin, when compared NOD1-/- and NOD2-/- infected animals to WT infected ones. Although there was no difference in TRAP-positive cells number evaluated in the alveolar bone crest among the studied groups, WT infected animals showed elevated ratio RANKL/OPG when compared to NOD2-/- infected animals. Moreover, the expression of osteoclasts activity markers, cathepsin k and matrix metalloproteinase-9, was significantly lower in NOD1-/- and NOD2-/- infected animals compared to WT infected ones. These results suggest that NOD1 and NOD2 receptors contribute to progression of bone resorption in experimental model of periodontitis, since the lack of NOD like receptors impair the bone resorption.

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Lafon, Arnaud. "Evaluation du rôle de l'inflammation buccale sur l'athérogénèse dans la survenue des accidents vasculaires cérébraux ischémiques." Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOMU08.

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Le but de ce travail est d’étudier le lien suspecté entre l’inflammation buccale et la survenue des AVC ischémiques. Dans les pays occidentaux, l’incidence des infarctus cérébraux est en augmentation malgré les campagnes de prévention visant à limiter l’exposition aux facteurs de risque classiques des pathologies ischémiques. Près de 9% des accidents vasculaires cérébraux sont sans étiologie connue. Le facteur déclenchant de l’AVC ischémique ou le « key trigger » reste inconnu. Des études récentes montrent qu’un AVC ischémique est plus susceptible de se déclencher dans la semaine qui suit un événement infectieux. De ce fait, l’inflammation buccale entraînant une élévation de différents biomarqueurs inflammatoires est susceptible de favoriser la survenue des AVC. Dans un premier temps, une méta-analyse a été effectuée afin de faire la synthèse des données étudiant la relation entre l’inflammation buccale et la survenue des AVC. Elle a montré que le risque d’avoir un AVC ischémique fatal augmente de 38% chez les sujets atteints de parodontite sévère. Dans un deuxième temps, deux études cliniques observationnelles ont été mises en place afin de renforcer la validité des liens épidémiologiques supposés et d’apporter de nouveaux éléments dans la compréhension des mécanismes physiopathologiques liant l’inflammation buccale et la survenue des AVCI. Les résultats montrent une relation entre le degré d’inflammation buccale et les marqueurs biologiques athéromateux et inflammatoires. En effet, nos résultats montrent une augmentation des taux de CRP, de VLDL, de triglycérides et une diminution des taux de HDL lors d’une atteinte parodontale sévère. C’est la perte osseuse parmi les marqueurs cliniques de l’inflammation buccale aisément évaluable sur un panoramique dentaire, qui est la plus significativement liée au risque de la survenue des AVC ischémiques. Les résultats de cette thèse suggèrent que la présence d’un contexte buccal inflammatoire favoriserait la survenue le développement d’un AVCI. En outre, nos résultats confirment la nécessité d’une coopération entre l’odontologue et le neurologue afin d’améliorer la prise en charge du risque vasculaire chez un patient ayant un AVCI avec une inflammation buccale The aim of this work is to investigate the suspected link between oral inflammation and the occurrence of ischemic stroke. In Western countries, the incidence of ischemic stroke is rising despite prevention campaigns aiming at limiting the exposure to common risk factors for ischemic diseases. Nearly 9% of strokes are of unknown etiology. The triggering factor for ischemic stroke or "trigger key" remains unknown. Recent studies have shown that ischemic stroke is more likely to occur in the week following an infectious event. Therefore, oral inflammation, that causes a rise in various inflammatory biomarkers is studied as potentially increasing the risk of stroke. Firstly, a meta-analysis was performed to synthesize data about the relationship between oral inflammation and the occurrence of stroke. It has shown that the risk of fatal ischemic stroke increases by 38% in patients with severe periodontitis. Secondly, two observational clinical studies have been implemented to strengthen the validity of the supposed epidemiological links and bring new elements in our understanding about the pathophysiological mechanisms linking oral inflammation and the occurrence of ischemic stroke. The results show a proportional relationship between the degree of oral-inflammation and biological assessments that demonstrate pro-atherosclerotic and pro-inflammatory state. Indeed, we observe an increase in CRP levels, VLDL triglycerides and a decrease in HDL in patients with severe periodontal disease. Bone loss, that is easily measurable on a dental panoramic radiograph, appears to be the main risk factor of the occurrence of ischemic stroke.The results of this thesis show that the presence of an inflammatory oral environment is an additional marker for the discovery of a cardiovascular risk in patients combining other conventional risk factors of ischemic stroke. In addition, our results suggest the need for cooperation between the neurologists and odontologists to improve the management of cardiovascular risk in patients with ischemic stroke and oral inflammation

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Santos, Rui Manuel Machado. "Dinâmica óssea no conceito cone Morse: revisão bibliográfica." Master's thesis, [s.n.], 2010. http://hdl.handle.net/10284/2399.

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Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária Introdução: Implantes com plataforma tipo Cone Morse (CM) baseiam-se no princípio mecânico do “cone dentro de cone” que proporciona uma grande superfície de contacto entre o pilar protético e o implante. Vários autores concluíram que o uso destes implantes representa um procedimento de sucesso na reabilitação de arcos totais ou parcialmente edêntulos. Objectivo: Abordar as vantagens da utilização do implante CM, enquadrando-as no contexto biomecânico e microbiológico. Material e Métodos: A pesquisa bibliográfica foi feita sem qualquer tipo restrições temporais, e foram utilizados os motores de busca, Pubmed, Science direct e B on. Os critérios de selecção utilizados para os artigos incluíram meta análises, ensaios controlados randomizados e outros artigos de revisão escritos em Inglês e Português, foram seleccionados 72 artigos. Conclusão: Face à escassez de estudos relativamente a este tipo de conexão, e reconhecendo o papel do infiltrado inflamatório a este nível, apenas podemos concluir que existem vantagens no uso da conexão tipo cone morse e Plataforma Switching (PS), ao nível microbiológico e biomecânico e no impacto ao nível da estabilidade dos tecidos duros e moles circunjacentes. Introduction: Implants with platform type Morse Cone are based inside on the mechanical principle of the “cone of cone” that provides to a great faying surface between the prosthetic pilar and the implant. Some authors had concluded that the use of this type of implants represents a procedure of success in the whitewashing of total or partially arcs. Objective: To approach the advantages of the cone-morse implants use fitting in the biomechanic and microbiology context. Methods: Bibliography review was made without any type of time limits and had been used through search engines as Pub-med, Scielo Forums, Science Direct and B on, The used criteria for the papers had been the analyzed goal, random controlled tests and others papers of revision written in English and Portuguese, was selected 72 papers. Conclusion: Face to the scarcity of studies relatively to this type of connection, and recognizing the paper of the inflammatory at this level, we only can conclude that there are advantages in the use of the connection type cone morse and platform switching, at the microbiological and biomechanic level and in the impact at the level of the stability of the hard and soft tissues.

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Shuster, Mark D. "Physical and Chemical Modifications of Free Radical Scavengers to Reduce their Radioprotective Potentials for Bacterial Agents." University of Toledo / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1134418758.

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Wenski, Sebastian Leonhard [Verfasser], Helge Björn [Akademischer Betreuer] Bode, Helge Björn [Gutachter] Bode, and Eugen [Gutachter] Proschak. "Understanding the biosynthesis of fabclavines in entomopathogenic bacteria / Sebastian Leonhard Wenski ; Gutachter: Helge Björn Bode, Eugen Proschak ; Betreuer: Helge Björn Bode." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2020. http://d-nb.info/1233832077/34.

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Mendes, Elisa Donalisio Teixeira. "Banho de clorexidina para prevenção de colonização e infecção por micro-organismos multirresistentes na unidade de transplante de células tronco e hematopoiéticas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5134/tde-02052016-144208/.

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Introdução: Infecções relacionadas à assistência de saúde (IRAS) representam hoje um dos principais desafios da qualidade do cuidado do paciente, principalmente em pacientes submetido a transplante de células tronco e hematopoiéticas (TCTH) O banho diário com a clorexidina (CHG) degermante a 2% tem sido proposto principalmente em unidades de terapia intensivas (UTIs) para diminuir a colonização bacteriana do paciente e assim diminuir IRAS. O objetivo deste estudo foi avaliar o impacto do banho com CHG degermante a 2% em unidade de internação de TCTH na incidência de infecção e colonização por patógenos multirresistentes e ainda avaliar seu impacto na sensibilidade das bactérias ao antisséptico. Métodos: Foi realizado um estudo quasi-experimental, com duração de 9 anos, com início em janeiro/2005 até dezembro/2013. A intervenção foi iniciada em agosto de 2009, sendo que os períodos pré e pós-intervenção tiveram duração de 4,5 anos. As taxas de IRAS, infecção por gram-negativos multirresistentes e infecção e colonização por enterococo resistente a vancomicina (VRE) foram avaliadas através de série temporal, para estudar o impacto da intervenção. As concentrações inibitórias mínimas (CIM) das bactérias para a CHG com e sem o inibidor de bomba de efluxo (CCCP) foram avaliadas nos dois períodos. Os genes de resistência a CHG foram estudados por meio da PCR e a clonalidade dos isolados por eletroforese em campo pulsátil. Resultados: Foi observada redução significativa na incidência de infecção e colonização de VRE na unidade no período pós-intervenção (p: 0,001). Essa taxa permaneceu estável em outras UTIs clínicas do hospital. Contudo as taxas de infecção por Gram negativos multirresistentes aumentou nos últimos anos na unidade. Não ocorreu diminuição na taxa de IRAS na unidade. As CIMs testadas de CHG aumentaram nas amostras de VRE e K. pneumoniae após o período de exposição ao antisséptico, com queda importante da CIM após o uso do CCCP, revelando ser a bomba de efluxo, um importante mecanismo de resistência à CHG. As amostras de A. baumannii e P. aeruginosa não apresentaram aumento da CIM após período de exposição à clorexidina. As bombas de efluxo Ade A, B e C estiveram presentes na maioria dos A. baumannii do grupo controle (66%). A bomba cepA foi encontrada em 67% de todas as K. pneumoniae testadas e em 44,5% das P. aeruginosas do grupo pré intervenção. Observamos uma relação positiva entre a presença da CepA nas amostras de K. pneumoniae e a resposta ao CCCP: de todas as 49 amostras CepA positivas 67,3% obtiveram redução do seu MIC em 4 diluições após adição do CCCP. A avaliação de clonalidade demonstrou padrão policlonal das amostras de VRE, K. pneumoniae e A. baumannii avaliadas. Em relação às amostras de P. aeruginosa foi observado que no período pós-intervenção ocorreu predominância de um clone com > 80% semelhança em 10 das 22 amostras avaliadas pelo dendrograma. Conclusões: O banho de clorexidina teve impacto na redução da incidência de infecção e colonização por VRE na unidade de TCTH, e não teve o mesmo impacto nas bactérias gram-negativas. Os mecanismos moleculares de resistência à clorexidina estão intimamente ligados à presença de bomba de efluxo, sendo provavelmente o principal mecanismo de resistência e tolerância das bactérias ao antisséptico Background and objectives: Daily skin cleansing with 2% chlorhexidine gluconate (CHG) in patients in intensive care unit is associated with reduction in incidence of multiresistant microorganisms (MR). Data in Hematological Steam Cell Transplant (HSCT), however, is scarce, and studies addressing the impact of this intervention in this population are needed. The aim of this study was to evaluate the effectiveness of daily bathing with CHG in reducing infection and colonization by MR (vancomycin resistance Enterococcus -VRE, P. aeruginosa, A. baumannii and K. pneumoniae) in HSCT patients and also evaluated the antiseptic susceptibility comparing pre and post intervention period. Methods: We perform a 9 year pre and post interventional study. In August 2009, was implemented daily bathing with CHG, replacing regular soap in all patients in a 12 beds HSCT ward, located in a tertiary reference hospital in Sao Paulo/Brazil. The goal of the intervention was decreasing MR prevalence in the unit. Therefore we evaluated the incidence-density (ID=cases/1000 patient days) of MR colonization and infection in periods of 4.5 years before and 4.5 years after intervention. Minimum inhibitory concentration (MIC) values were tested for CHG using Muller-Hinton agar dilution in MR strains isolated pre and post intervention period. The behavior of the strains after introduction of an efflux pump inhibitor (CCCP) was also assessed to study the importance of this resistance mechanism in relation to CHG. Statistical analyzes were performed using time-series analyses in ARIMA model, and SPSS program was used. P < 0.05 was considered statistically significant. Results: A significant reduction in infection and colonization VRE incidence was observed in post-intervention period (p 0.001). The opposite occurred with gran-negative infection and colonization rates, which had increased in recent years at the unit (p < 0.001). Rates of blood stream infection (BSI) remained stable in both periods. The VRE and K. pneumoniae strains showed two fold MIC 50 increase in in the post exposure period. However the strains of P. aeruginosa and A. baumannii had no MIC 50 increase after antiseptic exposure period. All MIC 50 strains was significant reduced after using the efflux pump inhibitor (CCCP) Conclusions: The CHG bath showed to be effective in reducing VRE infection and colonization in HSCT unit, and corroborating the literature the same impact was not taken in gram-negative bacteria. The unit microbiota has been impacted by the CHG massive use, however the increase MIC seemed not influence the efficacy of intervention in VRE cases. Molecular mechanisms of resistance to chlorhexidine are closely linked to the presence of efflux pump

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Vural, Helena [Verfasser], Helge Björn [Gutachter] Bode, and Ralf [Gutachter] Heermann. "Interaction between entomopathogenic bacteria and their hosts / Helena Vural ; Gutachter: Helge Björn Bode, Ralf Heermann." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2021. http://d-nb.info/1239730241/34.

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Gouveia, Ana Isabel Escudeiro Aguiar. "Doença periodontal no cão." Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2009. http://hdl.handle.net/10400.5/1677.

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Dissertação de Mestrado Integrado em Medicina Veterinária A doença periodontal é a afecção mais comum da cavidade oral dos canídeos e afecta os tecidos de sustentação do dente que formam o periodonto, que é composto pela gengiva, pelo ligamento periodontal, pelo cemento e pelo osso alveolar. O agente etiológico da doença periodontal é a placa bacteriana acumulada sobre a superfície dos dentes. Vários outros factores parecem influenciar no desenvolvimento da doença periodontal tais como a raça, a genética, a idade, o comportamento de mastigação, a saúde geral, a oclusão dentária, a nutrição e a consistência dos alimentos. Inicialmente, a manifestação clínica da doença periodontal é a gengivite que é reversível se a placa bacteriana for removida. Se a gengivite não for controlada, conduz à periodontite que é irreversível e pode progredir para a destruição do osso alveolar e dos tecidos de suporte do dente. Estadios avançados da doença periodontal podem conduzir a complicações locais e sistémicas. As consequências locais incluem as fístulas oronasais, as lesões endo-periodontais, as fracturas patológicas, as complicações oculares, a osteomielite dos ossos maxilar e mandibular e o aumento da incidência de neoplasias orais. A nível sistémico podem estar associadas a doenças renais, hepáticas, pulmonares ou cardíacas, a alterações articulares e a meningite, entre outras. No nosso estudo foi avaliada a presença e o grau de doença periodontal em 196 cães de raça pura e de raça indeterminada. Os resultados obtidos mostraram que a doença periodontal era menos frequente nos cães de raça indeterminada (29%) quando comparados com os cães de raça pura (71%), sendo os de raças pequenas, tais como o Caniche, o Cocker Spaniel e o Yorkshire Terrier os mais afectados (44%). A faixa etária com maior incidência de doença periodontal encontrava-se entre os 9 e os 12 anos (38%), o que traduz uma população envelhecida. Os cães alimentados com rações duras e secas e os cães com acesso a materiais mastigáveis, que requerem maior preensão e mastigação, apresentaram menor evidência de doença periodontal quando comparados com os cães alimentados com comida caseira e com os cães que não tinham acesso a materiais mastigáveis. A melhor forma de tratar a doença periodontal é actuar na sua prevenção, de modo a reduzir a quantidade de bactérias da cavidade oral, sendo a escovagem diária dos dentes o melhor método para evitar a deposição de placa e cálculo dentários. Cabe ao médico veterinário sensibilizar os proprietários para o seu papel fundamental em casa e ensiná-los desde cedo a escovar os dentes dos seus animais, não esquecendo que para além da higiene oral diária, devem procurar a ajuda profissional pelo menos uma vez por ano. ABSTRACT - PERIODONTAL DISEASE IN DOGS - Periodontal disease is the most common disease of the canine oral cavity and affects the supporting tissues of the teeth that form the periodontum, which includes gingiva, periodontal ligament, cementum and alveolar bone. Every dog will be affected to some extent with periodontal disease during its life. Periodontal disease’s etiologic agent is the bacterial plaque accumulated on teeth surfaces. Several other factors seem to predispose to the development of periodontal disease such as breed, genetics, age, chewing behaviour, health status, dental occlusion, nutrition and food consistency. Initially, the clinic evidence of periodontal disease is gingivitis which is reversible if the bacterial plaque is removed. Untreated, gingivitis may progress to periodontitis which is irreversible and progresses to destruction of alveolar bone and supporting tissues. Advanced stages of periodontal disease can lead to local and systemic consequences. The local consequences include oronasal fistulas, perio-endodontic lesions, pathologic fractures, ocular complications, maxilar and mandibular osteomyelitis, and an increased incidence of oral cancer. Systemic diseases secondary to periodontal disease include renal, hepatic, pulmonary and cardiac diseases. In our study 196 purebred and mixed-breed dogs were evaluated for the presence and grade of periodontal disease. The results showed that periodontal disease was less frequent in mixed-breed dogs (29%) than in purebred dogs (71%), and in the latter, the frequency was greater in the small breed dogs, such as Poodle, Cocker Spaniel and Yorkshire Terrier (44%). The age group with higher incidence of periodontal disease was between 9 and 12 years old (38%), reflecting an aging population. Dogs fed on dry and hard consistency food and those which had access to chewing materials, wich requires a certain degree of prehension and mastigation, had less evidence of periodontal disease than dogs fed on homemade and food with a certain degree of humidity and than dogs that had no access to chewing materials. The best way to treat periodontal disease is to prevent it, reducing the amount of bacteria in the oral cavity, the daily brushing of the teeth beeing the best method to prevent the deposition of dental plaque and calculus. Veterinary clinicians should alert the owners about their crucial role at home and teach them to brush the teeth of their animals from the beginning, without forgetting that in addition to daily oral hygiene, they should seek professional help at least once a year.

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Polo, Aguado Lorena. "Design of smart scaffolds for the treatment and prevention of bone infection." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/111824.

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La presente tesis doctoral, titulada "Diseño de scaffolds inteligentes para la prevención y tratamiento de la infección ósea", se centra en el desarrollo de materiales híbridos orgánico-inorgánicos capaces de realizar una liberación controlada de fármacos con fines biomédicos. En el primer capítulo, se presenta una introducción general sobre química supramolecular, materiales híbridos orgánico-inorgánicos y materiales porosos. En el segundo capítulo, se presentan tres proyectos sobre el diseño de puertas moleculares. En el primero, se muestran dos sistemas basados en el uso de un vidrio mesoporoso que actúa como soporte inorgánico, cargado y funcionalizado con moléculas orgánicas para llevar a cabo una liberación controlada de sustancias. La primera puerta molecular está compuesta por aminas y adenosín 5'-trifosfato (ATP), y la segunda está formada por 3-(trietoxisilil)propilisocianato unido a polímeros de ε-poli-L-lisina. Los dos sistemas se han caracterizado por resonancia magnética nuclear en estado sólido (RMN) y espectroscopía infrarroja por transformada de Fourier (FTIR). También se han estudiado las propiedades bioactivas de ambos materiales. Después, ambas puertas moleculares se han implementado en sólidos cargados con el objetivo de demostrar se podía realizar una liberación controlada de la carga. En el primer caso, el soporte mesoporoso se ha cargado con doxorubicina y se ha tapizado con moléculas de ATP. El sistema se ha validado in vitro con células humanas de osteosarcoma (HOS). En el segundo caso, el soporte mesoporoso se ha cargado con levofloxacino y se ha tapizado con ε-poli-L-lisina, y el sistema se validado con bacterias E.coli. Una vez descritos estos sistemas, se presenta una segunda publicación donde también se utiliza la puerta molecular de ATP. En este caso, el vidrio mesoporoso bioactivo que actúa como soporte inorgánico tiene una composición de 80%SiO2-15%CaO-5%P2O5, y se ha cargado con levofloxacino con el objetivo de conseguir propiedades antibióticas. El sólido se ha caracterizado mediante las técnicas correspoondientes, y se han estudiado sus propiedades bioactivas. Finalmente, se han utilizado bacterias E.coli para demostrar que el sólido posee actividad antibiótica, y es capaz de llevarala a cabo solo en presencia de fosfatasa ácida. El tercer proyecto presentado consiste en un soporte de MCM-41cargado con un colorante y funcionalizado con una secuencia peptídica que actúa como puerta molecular. El estímulo usado en este caso es la proteasa V8, típica del microorganismo S. aureus. El sistema ha sido correspondientemente caracterizado, y se han testado sus propiedades de liberación controlada de sustancias in vitro, demostrando la eficiencia del diseño. En el tercer capítulo, se utiliza un derivado de un componente de aceites esenciales (vanillina) para funcionar microesferas y scaffolds de fosfato de calcio, para dotarlos de propiedades antibióticas. En primer lugar, se ha sintetizado y se ha caracterizado el compuesto derivado de la vanillina, y se ha anclado en la superficie de los materiales de fosfato cálcico. Después, se han estudiado las propiedades antimicrobianas de ambos materiales en presencia de bacterias E.coli. También se han llevado a cabo ensayos de citotoxicidad con células tipo-fibroblasto L929 ynsayos de biocompatibilidad con células humanas tipo-osteoblasto MG-63, demostrando que las propiedades osteoregenerativas de los materiales originales no se ven modificadas tras el proceso de funcionalización. En resumen, se puede concluir que los resultados obtenidos a lo largo de esta tesis han contribuido al campo de los materiales de liberación controlada y de los materiales con efecto antibactérico. Estos nuevos diseños pueden ser clave en futuras aplicaciones para la investigación biotecnológica y biomédica, particularmente en terapias para la regeneración y contra la infección ósea. This thesis, entitled "Design of smart scaffolds for the treatment and prevention of bone infection", is focused on the development of smart organic-inorganic hybrid materials capable of perform controlled-delivery of drugs with biomedical purposes. In the first chapter, a general introduction about supramolecular chemistry, organic-inorganic hybrid materials and porous materials is given. The characterization and applications of porous materials are extensively explained, since those contents are highly related to the developing of this thesis. In the second chapter, three projects based on the design of gated devices are presented. In the first publication, two gated systems based on the use of a mesoporous silica material as an inorganic support, loaded and functionalised with organic molecules to achieve a controlled drug release are studied. The first molecular gate is composed by amino moieties and adenosine 5'-triphosphate (ATP), and the second one is composed by 3-(triethoxysilyl)propylisocyanate linked to ε-poly-L-lysine polymers. The two systems were characterized by solid state nuclear magnetic resonance (NMR) and Fourier transformed infrared spectroscopy (FTIR). The bioactivity capabilities of the materials were also studied. Then, both molecular gates have been implemented in loaded solids in order to demonstrate their controlled-release capabilities. In a first case, the mesoporous support was loaded with doxorubicin and capped with ATP molecules, and the system has been validated in a human osteosarcoma cell culture test. In a second case, the mesoporous support was loaded with levofloxacin and capped with the ε-poly-L-lysine molecular gates, and the system has been validated with E.coli bacteria. Once these two systems are described, a second project with the ATP molecular gates is presented. In this case, the mesoporous bioactive glass which acts as support has a composition of 80%SiO2-15%CaO-5%P2O5, and it has been loaded with levofloxacin with the purpose of killing bacteria. The solid has been characterized by corresponding techniques, and its bioactive properties have been studied. Finally, E.coli bacteria have been used to demonstrate that the solid is able to perform an antimicrobial activity only in the presence of acid phosphatase. The third project consists of a MCM-41 support loaded with a dye and capped with a peptide sequence. The trigger used in this case is the V8 protease, typical of the microorganism S. aureus. The system has been correspondingly characterized, and its drug release properties in vitro have been tested, demonstrating the efficiency of the design. In the third chapter, calcium phosphate microspheres and scaffolds have been functionalised with an essential-oil component derivative in order to achieve antibacterial properties. First, the vanillin-derivative has been synthesized and characterised, and in a second step, it has been attached to the surface of the calcium phosphate materials. Then, the antimicrobial properties of both materials have been tested against E.coli bacteria. Cytotoxicity assays with L929 fibroblast-like cells have been performed in order to demonstrate that the functionalized scaffolds did not perform a cytototxic effect. Finally, biocompatibility assays have been made with MG-63 human osteoblast-like cells, demonstrating that the functionalization of the scaffolds with vanillin do not affect their osteoregenerative properties. To sum up, it can be concluded that the results obtained in this thesis have contributed to the field of stimuli-responsive materials and antibacterial devices. The new designs could be key in the development of future applications in biotechology and biomedical research, particularly in bone infection and bone regeneration therapeutics. La present tesi doctoral, titulada "Disseny de scaffolds intel·ligents per la prevenció i tractament de la infecció òssia", es centra en el desenvolupament de materials híbrids orgànic-inorgànics capaços de realitzar una lliberació controlada de fàrmacs amb propòsits biomèdics. En el primer capítol, es presenta una introducció general sobre química supramolecular, materials híbrids orgànic-inorgànics i materials porosos. També s'explica extensivament la caracterització i les aplicacions d'aquests materials, ja que estos continguts estan altament relacionats amb el desenvolupament d'aquesta tesi. En el segon capítol, es presenten tres projectes sobre el disseny de portes moleculars. En el primer, es mostren dos sistemes basats en l'ús d'un vidre mesoporós que actua com a suport inorgànic, carregat i funcionalitzat amb molècules orgàniques per a dur a terme una lliberació controlada de substàncies. La primera porta molecular està formada per amines i adenosín 5'-trifosfat (ATP), i la segona està formada per 3-(trimetoxisilil)propilisocianat unit a polímers de ε-poli-L-lisina. Els dos sistemes s'han caracteritzat per resonància magnètica nuclear en estat sòlid (RMN) i espectroscopia infrarroja per transformada de Fourier (FTIR). També s'han estudiat les propietats bioactives de ambdós materials. Després, ambdues portes moleculars han sigut implementades en sòlids carregats amb l'objectiu de demostrar que es pot realitzar una lliberació controlada de la càrrega. En el primer cas, el suport mesoporós s'ha carregat amb doxorrubicina, i el sistema s'ha validat in vitro amb cèl·lules humanes d'osteosarcoma (HOS). En el segon cas, el suport mesoporós s'ha carregat amb levofloxací i s'ha entapissat amb ε-poli-L-lisina; el sistema s'ha validat amb bacteris E.coli. Una volta descrits aquests sistemes, es presenta una segona publicació on també s'utilitza la porta molecular d'ATP. En aquest cas, el vidre mesoporós bioactiu que actua com a suport inorgànic té una composició de 80%SiO2-15%CaO-5%P2O5., y s'ha carregat amb levofloxací amb l'objectiu d'aconseguir propietats antibiòtiques. El sòlid s'ha caracteritzat mitjançant les tècniques corresponents, i s'han estudiat les seues propietats bioactives. Finalment, s'han utilitzat bacteris E.coli per demostrar que el sòlid posseïx activitat antibiòtica, i que és capaç de dur-la a terme solament en presència de fosfatasa àcida. El tercer projecte presentat consisteix en un suport de MCM-41 carregat amb un colorant i funcionalitzat amb una seqüència peptídica que actua com a porta molecular. L'estímul utilitzat en aquest cas és la proteasa V8, típica del microorganisme S. aureus. El sistema ha sigut corresponentment caracteritzat, i s'han testat les seues propietats de lliberació controlada de substàncies in vitro, demostrant l'eficàcia del disseny. En el tercer capítol, s'ha utilitzat un derivat d'un component d'olis essencials (vanil·lina) per funcionalitzar microesferes i scaffolds de fosfat de calci amb l'objectiu de dotar-los de propietats antibiòtiques. En primer lloc, s'ha sintetitzat y caracteritzat el compost derivat de la vanil·lina, i s'ha unit a la superfície dels materials de fosfat càlcic. Després, s'han estudiar les propietats antimicrobianes d'ambdós materials en presència de bacteris E.coli. S'han dut a terme assajos de citotoxicitat amb cèl·lules tipus fibroblast L929i assajos de biocompatibilitat amb cèl·lules humanes tipus-osteoblast MG-63, demostrant que les propietats osteoregeneratives dels materials originals no es veuen modificades després del procés de funcionalització. En resum, es pot concluir que els resultats obtinguts en aquesta tesi han contribuït al camp dels materials de lliberació control·lada i materials amb propietats antibacterianes. Els nous dissenys poden ser claus per al desenvolupament de futures aplicacions en la recerca biotecnològica i bi Polo Aguado, L. (2018). Design of smart scaffolds for the treatment and prevention of bone infection [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/111824 TESIS

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Brandt, Paul Dieter. "Shear bond strength, microleakage and anti-bacterial properties of self-etching bonding systems." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-02182010-110040/.

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Qasemi, Adel, and Radhi Zayny. "The effect of preoperative brushing with chlorhexidine gel on bacterial contamination of bone transplant A clinical laboratory study." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19855.

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Introduktion: Förlust av tänder är idag vanligt förekommande och kan behandlas med hjälp av dentala implantat. För att installation av implantat ska vara möjlig, krävs tillräcklig benvolym där implantat ska installeras. När det föreligger bendefekter i anslutning till det lokala området för implantatinstallationen utgör simultaneous augmentation technique eller enstegsteknik ett behandlingsalternativ för bentransplantat. För att minimera kontamination med orala bakterier av det uppsamlade benet under beninsamlingsmetoder, används idag preoperativ sköljning med klorhexidin som ett steg i behandlingen.Syftet med denna studie är att undersöka möjligheten till ytterligare minimering av bakteriell kontamination vid implantatinstallation, med hjälp borstning av munhålan med klorhexidingel.Metod: 30 patienter deltog i en dubbelblindad, randomiserad studie där 15 patienter utgjorde en kontrollgrupp och 15 andra patienter fick genomgå den införda preoperativa tilläggsåtgärden. Ben- och paperpoint prov togs från samtliga patienter för bakteriell odling. Antalet kontaminerande bakterier uttrycktes som kolonibildande enheter (CFU/ml). En statistisk analys gjordes för att beräkna bakterieantal och kontaminationsgraden i respektive prov. Resultat: Medelvärdet för antal bakterier i benproven från samtliga patienter i kontrollgruppen beräknades till 8 126 CFU/ml respektive 2 946 CFU/ml i testgruppen dock var skillnaden inte signifikant (P = 0,357).Konklusion: Resultatet i denna studie visar ingen statistisk signifikant skillnad mellan patienter som erhållit den preoperativa profylaktiska tilläggsåtgärden, borstning med klorhexidingel, och patienter som inte erhållit detta hygiensupplement. Dessutom kunde ingen slutsats dras gällande effekten av denna tilläggsmetod på virulenta bakteriearterna P. gingivalis, P. Intermedia och A. actinomycetemcomitans. Ett större patientunderlag krävs i framtida randomiserade kontrollerade studier för att utvärdera denna metods effekt. Introduction: Missing teeth can be replaced by dental implants. To achieve good results using dental implants, it is important that there is sufficient bone volume. In cases with bone defects, simultaneous augmentation technique becomes an alternative for bone augmentation. To minimize the contamination with oral bacteria during the bone collection, preoperative rinsing with chlorhexidine is today commonly used as a step in the treatment.The aim of this study is to examine the additional effect of preoperative brushing with chlorhexidine gel on avoiding bacterial contamination during the installation of dental implants.Method: 30 patients participated in a randomized, double blinded study. 15 patients were included in the control group and 15 patients underwent an additional step in the treatment with a preoperative brushing with chlorhexidine gel. Bone samples and paperpoint samples were collected and analyzed in a laboratory and a statistic analysis was performed to compare the number of bacterial colonies in samples from the two groups (CFU/ml) present and the degree of contamination.Results: The mean bacterial count in bone samples from all patients in the control group was calculated at 8 126 CFU/ml and 2 946 CFU/ml in the test group. CFU/ml was different between the groups (P = 0.357) but the difference was not significant (P <0.05).Conclusion: Brushing with chlorhexidine gel preoperatively showed no significant effects in the bacterial contamination of bone chips. No recommendation for adding this additional step in the standard treatment with dental implants can therefore be made today.

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23

Nilsson, Lina Maria. "Molecular mechanism and physiological implications of shear-enhanced bacterial adhesion via the FimH catch bond /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17258.

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24

Grammbitter, Gina Luisa Carina [Verfasser], Helge B. jörn [Gutachter] Bode, and Martin [Gutachter] Grininger. "Characterization of PKS II systems from entomopathogenic bacteria / Gina Luisa Carina Grammbitter ; Gutachter: Helge B.jörn Bode, Martin Grininger." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2021. http://d-nb.info/1228979057/34.

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25

Leite, Rachel Russo. "Infecção de corrente sanguínea em pacientes ambulatoriais transplantados de medula óssea." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5134/tde-26012012-093429/.

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Introdução: Infecção de corrente sanguínea é uma das principais complicações dos pacientes transplantados de medula óssea. Poucos estudos avaliam os pacientes transplantados que realizam acompanhamento ambulatorial. Objetivos: Descrever o perfil dos agentes isolados de infecção de corrente sanguínea de pacientes transplantados que realizam acompanhamento ambulatorial no HCFMUSP. Avaliar a proporção e fatores de risco associados com internação e óbitos desses pacientes. Método: Análise retrospectiva dos prontuários de pacientes acompanhados no ambulatório de TMO que apresentaram hemocultura positiva colhida durante janeiro de 2004 a dezembro de 2008. Os dados foram analisados utilizando o Epi Info 3.5.1, o nível de significância adotado foi de 5%. Hospitalização e óbito em 30 dias foram os desfechos avaliados e foram calculados fatores de risco associados nas análises bivariada e multivariada. Resultados: Os principais agentes isolados foram S. maltophilia (15%), SCN (12%), Acinectobacter spp (9%). Dos episódios ocorridos, 88% eram monomicrobianos e 12% polimicrobianos, em ambas a ocorrência de gram-negativos foi predominante. A internação hospitalar ocorreu em 26% dos episódios, sendo encontrado na analise bivariada e multivariada como fator protetor a realização de transplante autólogo. O óbito em 30 dias ocorreu em 10% dos isolados e foi encontrado, na análise bivariada, como fator de risco o isolamento de gram-positivos e a presença de neutropenia grave. A análise multivariada encontrou como fator protetor para óbito em 30 dias o uso do score MASCC, não sendo evidenciados fatores de risco. Conclusões: Os gram-negativos foram os principais agentes isolados neste estudo, destacando-se o isolamento de Stenotrophomonas maltophilia. A ocorrência de hospitalização e óbito não foi elevada, o transplante autólogo foi fator protetor para hospitalização e o uso do score MASCC fator protetor pra óbito em 30 dias. Mais estudos que avaliem o tratamento ambulatorial de pacientes transplantados de medula óssea a fim de possibilitar uma melhor qualidade de vida desses pacientes são necessários Introduction: bloodstream infection is one of the most common medical complications in bone marrow transplanted patients. A few studies in fact evaluate the transplanted patients that are under outpatient attendance. Objectives: Describe the isolated bloodstream infection agents profile on bone marrow transplanted patients that are under outpatient attendance at HCFMUSP. Evaluate the proportion and risk factors associated with hospitalization and death of such patients. Method: Retrospective analysis on patients records of the TMOs ambulatory that presents positive blood culture gathered between January 2004 and December 2008. All the data was analyzed using the software Epi Info version 3.5.1, the significance level adopted was of 5%. Hospitalization and death in 30 days were the outcomes evaluated and which the risk factors associated were calculated and compared through the analysis bivariate and multivariate. Results: The most important agents isolated were S. maltophilia (15%), SCN (12%), Acinectobacter spp (9%). From all the episodes that occurred, 88% were monomicrobial and 12% polimicrobial, in both the occurrence of gram-negative was predominant. The hospitalization happened in 26% of the episodes, being found as the protection factor to the autologous transplant on both analyses, bivariate and multivariate. On 10% of the isolated cases occurred death in 30 days, and it was found in the bivariate analysis as factor of risk the isolation of the gramnegative and the presence of serious neutropenia. The multivariate analysis found as protection factor for death in 30 days score MASCC score use and a part of that no risk factors were highlighted. Conclusion: The gram-negative were the most important isolated agents in this research, highlighting the isolation of Stenotrophomonas maltophilia. The occurrence of hospitalization and death wasnt high, being the autologous transplant a protection factor for hospitalization and the use of MASCC score the protection factor for death in 30 days. More research is necessary evaluating the outpatient treatment for bone marrow transplanted patients to make it possible a better life standard for those patients

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Zhang, Xueying. "Identification, properties, and application of enterocins produced by enterococcal isolates from foods." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1206069582.

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27

Yang, Kun-Yun. "The effects of the N(5) hydrogen bond and the re-face positive charge on the redox properties of flavin in the methylotrophic bacterium W3A1 electron transfer flavoprotein." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150407209.

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Fuchs, Sebastian [Verfasser], Helge B. [Akademischer Betreuer] Bode, and Eckhard [Akademischer Betreuer] Boles. "Investigation of the biosynthesis of bacterial natural products / Sebastian Fuchs. Gutachter: Helge B. Bode ; Eckhard Boles." Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2014. http://d-nb.info/1046888994/34.

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29

Misner, Scottie, and Evelyn Whitmer. "Assessment of Doneness in Cooked Ground Beef." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2012. http://hdl.handle.net/10150/239594.

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30

Kumsa, Bersissa. "Molecular investigation of arthropods and vector-borne bacteria from Ethiopia." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5054/document.

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En outre, nous avons fait une expérience sur les nouveaux outils pour identifier les tiques par MALDI-TOF MS protéines profilage et des méthodes moléculaires. Notre étude visant à explorer les bactéries dans les ixodidae prélevés sur des animaux domestiques en Éthiopie a révélé une prévalence globale de 6% (46/767) des rickettsies de SFG, 3,8% (29/767) ADN de Borrelia et 6,4% (54/842) de C. burnetii dans différentes espèces de tiques. L'étude pour étudier les bactéries dans 303 puces prélevés sur des chiens et des chats domestiques en Ethiopie qui ont été identifiés comme étant morphologiquement Ctenocephalides felis felis, Ctenocephalides canis, Pulex irritans et Echidnophaga gallinacé montré Rickettsia felis dans 21% des puces, principalement dans Ctenocephalides felis, avec un semblable prévalence dans les puces de chiens et de chats. La présence d'Acinetobacter spp. dans M. ovinus, Heterodoxus spiniger, Bovicola ovis et Linognathus vituli. La séquence du gène rpoB partiel a révélé la présence de A. soli, A. lowffii, A. Pitti et 3 nouveaux Acinetobacter spp. dans les poux et Keds. Bartonella melophagi a été identifié par une PCR standard, suivi par un séquençage du fragment de la gltA et gène rpoB chez M. ovinus. Dans l'ensemble, nos résultats alerte les médecins en charge des patients avec fièvre d'étiologie inconnue en Ethiopie et ceux qui se soucient de voyageurs en provenance de l'Ethiopie à prendre en compte la présence de plusieurs espèces zoonotiques à transmission vectorielle de bactéries, y compris SFG rickettsies, C. burnetii, R. felis, B. henselae et B. melophagi comme agents pathogènes potentiels Our study to explore bacteria in ixodid ticks collected from domestic animals in Ethiopia revealed an overall prevalence of 6% (46/767) SFG rickettsiae, 3.8% (29/767) Borrelia DNA and 6.4% (54/842) C. burnetii in different tick species. The study to investigate bacteria in 303 fleas collected from domestic dogs and cats in Ethiopia that were morphologically identified as Ctenocephalides felis felis, Ctenocephalides canis, Pulex irritans and Echidnophaga gallinacean showed Rickettsia felis in 21% of fleas, mainly in Ctenocephalides felis, with a similar prevalence in fleas from dogs and cats. The study to investigate bacteria in lice and sheep ked (Melophagus ovinus) revealed Acinetobacter spp. in M. ovinus, Heterodoxus spiniger, Bovicola ovis and Linognathus vituli. Partial rpoB gene sequence revealed A. soli, A. lowffii, A. pitti and 3 new Acinetobacter spp. in the lice and keds. Molecular identification of lice using an 18S rRNA gene analysis confirmed the morphological methods of lice identification. Bartonella melophagi was identified by standard PCR followed by sequencing of fragments of the gltA and rpoB genes in M. ovinus.Overall, our findings alert physicians managing patients with fever of unknown aetiology in Ethiopia and those who care for travellers from Ethiopia to consider the presence of several vector-borne zoonotic species of bacteria including SFG rickettsiae, C. burnetii, R. felis, B. henselae and B. melophagi as potential causative agents

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Frank, Anna Carolin. "Lifestyle and Genome Evolution in Vector-Borne Bacteria : A Comparison of Three Bartonella Species." Doctoral thesis, Uppsala universitet, Molekylär evolution, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5913.

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Bacterial genomes provide records of the molecular processes associated with emergence and evolution of different bacterial lifestyles. This thesis is based on whole-genome comparisons within the genus Bartonella, an excellent model system for studies of host- and vector-specificity and infection outcome in animal-associated bacteria. The louse-borne human specialist and trench fever agent Bartonella quintana was contrasted to the flea-borne generalist relatives Bartonella henselae and Bartonella grahamii, which cause asymptomatic infection in cat and mouse respectively. While B. henselae is commonly isolated from humans, and causes cat scratch disease, there is only one reported case of B. grahamii human infection. The gene complements of the three species are nested like Russian dolls with the smaller genome (B. quintana) being entirely contained in the medium sized (B. henselae), which in turned is contained in the largest (B. grahamii). Size differences reflect differences in the horizontally and vertically acquired gene content, and in the number of genus- and species- specific genes, owing to differential impact of bacteriophages and plasmids, and to different degrees of genome decay. These processes can be attributed to the three distinct lifestyles. Comparisons with other alpha-proteobacteria suggest that the Bartonella genus as a whole evolved from plant-associated species, and that horizontal transfer, in particular of genes involved in interaction with the host, played a key role in the transition to animal intracellular lifestyle. The long-term genome decay associated with this lifestyle is most advanced in the host-restricted B. quintana. The broad host-range species B. grahamii has the largest genome and the largest proportion of auxiliary DNA of the three, probably because it has access to a larger gene pool. In encodes all the known pathogenicity determinants found in the genomes of B. henselae and B. quintana, suggesting that these genes primarily evolved to facilitate colonization in the reservoir host.

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32

Júnior, Flávio Ferraz de Campos. "Formação de biofilme bacteriano sobre polimetilmetacrilato usado como cimento ósseo." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-05052010-110709/.

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A infecção bacteriana é a principal complicação que um procedimento de artroplastia de quadril ou joelho pode apresentar. Mesmo após a incorporação de antibiótico (gentamicina) ao cimento ósseo, as taxas de infecções após este procedimento cirúrgico continuam gerando sérios prejuízos para o hospital e para o paciente. As principais bactérias envolvidas nas infecções relacionadas aos implantes ortopédicos são Pseudomonas aeruginosa, Staphylococcus aureus e Staphylococcus epidermidis. O objetivo deste trabalho foi avaliar a aderência e formação de biofilme de S. aureus, S. epidermidis e P. aeruginosa sobre o cimento ósseo polimetilmetacrilato (PMMA) com e sem antibiótico (gentamicina), de procedência nacional e internacional, por meio de microscópio eletrônico de varredura (MEV) e por cultura. Também, estimar quantitativamente as células viáveis recuperadas dos biofilmes formados. Foram produzidos discos de polimetilmetacrilato de 10,0 mm de diâmetro e 3,0 mm de espessura. Foram utilizadas cepas Pseudomonas aeruginosa - ATCC 27853, Staphylococcus epidermidis - ATCC 12228 e Staphylococcus aureus - ATCC 25932. Para este estudo foram utilizados corpos-de-prova de cimento ósseo de procedência nacional (BAUMER, CMM e BIOMECANICA) e internacional (BIOMET com gentamicina, BIOMET sem gentamicina e SIMPLEX). Biofilmes foram produzidos in vitro a partir da inoculação da suspensão bacteriana (\'10 POT.8\' unidades formadoras de colônia/mL) em Tryptic Soy Broth e incubados nos períodos de tempo de 1, 6, 24, 48, e 72 horas. Após os períodos de incubação os corpos-de-prova foram removidos do meio de cultura, lavados, sonicados e do sobrenadante realizadas diluições seriadas (\'10 POT.-1\' a \'10 POT.-5\'). A seguir, os corpos-de-prova foram preparados para observação por MEV. Os resultados de MEV mostraram bacilos e cocos aderidos e agrupados formando biofilme. Para P. aeruginosa: as contagens das células viáveis em média (UFC/mL) foram de 2,8 \'+ OU -\' 1,7 x \'10 POT.6\' (BAUMER), 1,7 \'+ OU -\' 0,9 x \'10 POT.6\' (BIOMECANICA), 1,7 \'+ OU -\' 0,7 x \'10 POT.6\' (CMM), 1,6 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMET sem gentamicina), 6,0 \'+ OU -\' 5,5 x \'10 POT.4\' (BIOMET com gentamicina) e 1,9 \'+ OU -\' 0,9 x \'10 POT.6\' (SIMPLEX); para S. epidermidis: 1,3 \'+ OU -\' 0,1 x \'10 POT.6\' (BAUMER), 1,5 \'+ OU -\' 0,2 x \'10 POT.6\' (BIOMECANICA), 2,3 \'+ OU -\' 1,7 x \'10 POT.6\' (CMM), 1,5 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMET sem gentamicina), 1,5 \'+ OU -\' 0,2 x \'10 POT.6\' (BIOMET com gentamicina) e 1,2 \'+ OU -\' 0,1 x \'10 POT.6\' (SIMPLEX); para S. aureus: 1,7 \'+ OU -\' 0,8 x \'10 POT.6\' (BAUMER), 1,6 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMECANICA), 1,4 \'+ OU -\' 0,6 x \'10 POT.6\' (CMM), 1,1 \'+ OU -\' 0,5 x \'10 POT.6\' (BIOMET sem gentamicina), 3,0 \'+ OU -\' 6,0 x \'10 POT.5\' (BIOMET com gentamicina) e 1,3 \'+ OU -\' 0,6 x \'10 POT.6\' (SIMPLEX), respectivamente. Os dados obtidos mostraram que o cimento ósseo de polimetilmetacrilato com e sem gentamicina não evitaram a aderência da Pseudomonas aeruginosa, Staphylococcus epidermidis e Staphylococcus aureus e formação de biofilme, como demonstrado pela MEV. Em conclusão, isto é um fator de risco para infecções. The bacterial infection is the main complication of a procedure for hip or knee arthroplasty can present. Even after the addition of antibiotic (gentamicin) in the bone cement, the rates of infection after the surgical procedure continue causing serious damage to the hospital and the patient. The main bacteria involved in infections related to orthopedic implants are Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis. The objective of this study was to evaluate the adhesion and biolfilm formation of the S. aureus, S. epidermidis and P. aeruginosa on the bone cement polymethylmethacrylate (PMMA) with and without antibiotic (gentamicin) from national and international origin, by means scanning electron microscope (SEM) and by culture. Also, quantitatively estimate the viable cells recovered from biofilms formed. Discs of cement were produced from 10.0 mm in diameter and 3.0 mm thick. Strains used were Pseudomonas aeruginosa - ATCC 27853, Staphylococcus epidermidis - ATCC 12228 e Staphylococcus aureus - ATCC 25932. For this study we used coupons cement of national origin (Baumer, CMM and biomechanics) and international (BIOMET with gentamicin, BIOMET without gentamicin and SIMPLEX). Biofilms were produced in vitro from the inoculation of bacterial suspension (108 Colony-Forming Units/mL) in Tryptic Soy Broth and incubated for the time periods of 1, 6, 24, 48 and 72 hours. After the incubation periods of the coupons they were removed from the medium culture, washed, sonicated and serial dilutions of supernatant taken (\'10 POT.-1\' a \'10 POT.-5\'). Next, the coupons were prepared for observation by SEM. The results of SEM showed adherent cocci bacilli, and adhered to each other form a biofilm. For P. aeruginosa: the couting of viable cells on average (CFU/mL) were 2,8 \'+ OU -\' 1,7 x \'10 POT.6\' (BAUMER), 1,7 \'+ OU -\' 0,9 x \'10 POT.6\' (BIOMECANICA), 1,7 \'+ OU -\' 0,7 x \'10 POT.6\' (CMM), 1,6 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMET sem gentamicina), 6,0 \'+ OU -\' 5,5 x \'10 POT.4\' (BIOMET com gentamicina) e 1,9 \'+ OU -\' 0,9 x \'10 POT.6\' (SIMPLEX); para S. epidermidis: 1,3 \'+ OU -\' 0,1 x \'10 POT.6\' (BAUMER), 1,5 \'+ OU -\' 0,2 x \'10 POT.6\' (BIOMECANICA), 2,3 \'+ OU -\' 1,7 x \'10 POT.6\' (CMM), 1,5 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMET sem gentamicina), 1,5 \'+ OU -\' 0,2 x \'10 POT.6\' (BIOMET com gentamicina) e 1,2 \'+ OU -\' 0,1 x \'10 POT.6\' (SIMPLEX); para S. aureus: 1,7 \'+ OU -\' 0,8 x \'10 POT.6\' (BAUMER), 1,6 \'+ OU -\' 0,7 x \'10 POT.6\' (BIOMECANICA), 1,4 \'+ OU -\' 0,6 x \'10 POT.6\' (CMM), 1,1 \'+ OU -\' 0,5 x \'10 POT.6\' (BIOMET sem gentamicina), 3,0 \'+ OU -\' 6,0 x \'10 POT.5\' (BIOMET com gentamicina) e 1,3 \'+ OU -\' 0,6 x \'10 POT.6\' (SIMPLEX), respectively. The data showed that of polymethylmethacrylate bone cement with and without gentamicin did not prevent the adhesion of Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus aureus and formation of biofilms, as demonstrated by SEM. In conclusion, this is risk factor for infections.

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33

Misner, Scottie, and Evelyn Whitmer. "Food Safety Know-how." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146682.

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1p. Most of the "bad food" reported illnesses are due to bacterial contamination. Nearly all of these cases can be linked to improper food handling, both in our homes and in restaurants. This article briefly discusses the causes of food contamination and how to handle food safely.

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34

Alves, Ana Regina de Freitas. "Doenças alimentares de origem bacteriana." Master's thesis, [s.n.], 2012. http://hdl.handle.net/10284/3756.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas As doenças de origem alimentar têm-se revelado um enorme problema para o ser Humano, acarretando significativa morbilidade, mortalidade e custos económicos para a sociedade. Os fungos, os parasitas e as bactérias são os contaminantes biológicos com maior relevo em doenças alimentares. Bactérias como a Salmonella sp., Campylobacter, Escherichia coli, Listeria monocytogenes, Clostridium botulinum são, no panorama atual, algumas das bactérias com maior relevo e importância, sendo a causa de muitas das ocorrências de doenças alimentares (infeções/intoxicações alimentares), como o botulismo, a salmonelose, a listeriose que, dependendo da gravidade da doença, podem causar graves danos ao nível da saúde e da qualidade de vida dos indivíduos. Isto ocorre devido não só a falhas de segurança e qualidade do alimento ao longo do ciclo de vida do mesmo (cultivo, distribuição, preparação), como também devido a práticas incorretas, nomeadamente no uso inadequado de antibacterianos em humanos e animais. A qualidade e segurança alimentar contempla normas simples que podem garantir a qualidade final dos alimentos e deste modo prevenir e diminuir o número de ocorrências e surtos bacterianos associados ao consumo de alimentos contaminados. The foodborne diseases are a huge problem for the human being, causing significant morbidity, mortality and economic costs to society. Fungi, parasites and bacteria are the more relevant biological contaminants in eating disorders. Bacteria such as Salmonella sp., Campylobacter, Escherichia coli, Listeria monocytogenes, Clostridium botulinum are, in the current scenario, some of the bacteria with greater emphasis and importance, being the cause of many of the occurrences of foodborne diseases (infections / food poisoning), as botulism, salmonellosis, listeriosis, depending upon the severity of the disease may cause serious harm on health and quality of life of individuals. This is due not only to failures of safety and quality of food throughout the life cycle of the same (cultivation, distribution, preparation), but also due to incorrect practice, including the inadequate use of antibiotics in humans and animals. The food quality and safety standards include simple that can guarantee the final quality of the food and thus prevent and reduce the number of occurrences and bacterial outbreaks associated with the consumption of contaminated food.

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Santos, Fernanda Regina Ribeiro. "Ciclooxigenase-2 modula in vivo a expressão de marcadores da osteoclastogênese e genes envolvidos no metabolismo ósseo em resposta ao lipopolissacarídeo bacteriano." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/58/58135/tde-04072012-135640/.

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Durante a resposta inflamatória, diversos mediadores são liberados localmente com o objetivo de estimular a resposta imune celular e humoral. Por meio da ação das enzimas ciclooxigenases e lipoxigenases ocorrerão modificações estruturais na cadeia do ácido araquidônico levando a síntese de prostaglandinas ou leucotrienos e lipoxinas, respectivamente. Tais mediadores são responsáveis pela regulação da expressão dos genes RANK, RANKL e OPG, moduladores da osteoclastogênese. Dessa maneira, o objetivo deste estudo foi avaliar a expressão do RNA mensageiro (RNAm) para as enzimas envolvidas no metabolismo do ácido araquidônico, ciclooxigenase-2 (COX-2) e 5- lipoxigenase (5-LO), e para os mediadores da osteoclastogênese (RANK, RANKL e OPG) no tecido ósseo, após inoculação de lipopolissacarídeo bacteriano (LPS) nos canais radiculares de molares de camundongos. Posteriormente foi investigado o efeito do bloqueio farmacológico da via COX-2 induzida pelo LPS, na expressão de mediadores da osteoclastogênese e de genes envolvidos no metabolismo ósseo. Foram utilizados 144 camundongos C57BL/6, com 6 semanas de idade, pesando de 18 a 20 gramas, nos quais os canais radiculares dos primeiros molares foram inoculados com uma solução contendo lipopolissacarídeo bacteriano de E. coli (0,1, 1,0 e 10mg/ml). Decorridos os períodos experimentais de 7, 14, 21 e 28 dias, os animais foram submetidos à eutanásia e os blocos contendo dente e osso foram removidos para extração do RNA total. Em seguida, foi realizada a avaliação da expressão gênica por meio de transcrição reversa e reação da polimerase em cadeia em tempo real (qRT-PCR). A análise global da expressão de RNAm para proteínas envolvidas no metabolismo ósseo foi realizada por meio de um ensaio de PCR Array (Osteogenesis RT² Profiler PCR Array). Os valores de expressão relativa de cada RNAm, para cada grupo, foram comparados por meio da análise de variância (ANOVA) de duas vias seguido pelo pós-teste de Bonferroni ou por ANOVA de uma via seguido pelo pós-teste de Dunnett (&alpha = 0,05). A inoculação de LPS nos canais radiculares de molares de camundongos foi capaz de induzir a expressão dos genes PTGS2 e ALOX5, responsáveis pela codificação das enzimas COX-2 e 5-LO, envolvidas no metabolismo do ácido araquidônico, concomitantemente à modulação da expressão dos genes TNFRSF11A, TNFSF11 e TNFRSF11B, responsáveis pela codificação dos moduladores da osteoclastogênese RANK, RANKL e OPG, respectivamente. A administração de Indometacina, um inibidor não seletivo de COX-2, inibiu a expressão de RNAm para RANK e RANKL e estimulou a expressão de OPG durante os períodos iniciais de resposta à inoculação de LPS nos canais radiculares. A inibição da via COX-2 de metabolismo do ácido araquidônico nos períodos iniciais de resposta à inoculação de LPS nos canais radiculares modulou diferencialmente a expressão de genes envolvidos no catabolismo e anabolismo ósseo, indicando possíveis papéis para os mediadores derivados no ácido araquidônico na regulação do metabolismo ósseo. Estes resultados sugerem alvos terapêuticos importantes para intervenção precoce em doenças inflamatórias, como lesões periapicais para evitar a reabsorção do tecido ósseo. During an inflammatory response, several mediators are locally released in order to stimulate cellular and humoral immune response. Through the action of cyclooxygenase and lipoxygenase enzymes structural changes occur in the arachidonic acid chain leading to synthesis of prostaglandins or leukotrienes and lipoxins, respectively. Such mediators are responsible for the regulation of RANK, RANKL and OPG gene expression, osteoclastogenesis modulators. Thus, the objective of this study was to evaluate the expression of messenger RNA (mRNA) for the enzymes involved in arachidonic acid metabolism, cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO), and the osteoclastogenesis mediators (RANK, RANKL and OPG) in bone tissue after injection of bacterial lipopolysaccharide (LPS) in murine dental root canals. Then, COX-2 pathway was pharmacologically blocked for investigation of expression of osteoclastogenesis mediators and genes involved in bone metabolism. We used 144 C57BL/6 mice, 6 weeks-old, weighing 18-20 grams, which had the first molars root canals inoculated with a solution containing LPS from E. coli (0.1, 1.0 and 10 mg/ml). After 7, 14, 21 and 28 days the animals were euthanized and the tooth-and-bone blocks were removed for total RNA extraction. Subsequently, the evaluation of gene expression was performed by reverse transcription and polymerase chain reaction in real time (qRT-PCR). Global analysis of mRNA expression for proteins involved in bone metabolism was performed using PCR arrays (Osteogenesis RT² Profiler PCR Array). The values for relative expression of each mRNA for each group were compared using two-way analysis of variance (ANOVA) followed by Bonferroni post-test or one-way ANOVA followed by Dunnett\'s test (α=0.05). The injection of LPS into the root canals was induced expression of genes PTGS2 and ALOX5, responsible for encoding COX-2 and 5-LO enzymes, involved in the metabolism of arachidonic acid, simultaneously to the modulation of gene expression of TNFRSF11A, TNFSF11 and TNFRSF11B, responsible for encoding the osteoclastogenesis modulators RANK, RANKL and OPG, respectively. Administration of Indomethacin, a non-selective inhibitor of COX-2, inhibited the expression of mRNA for RANK and RANKL and stimulated the expression of OPG during the initial response to the root canals contamination with LPS. Inhibition of the COX-2 pathway from arachidonic acid metabolism in the initial periods of response to LPS injection into the root canals differentially modulated the expression of genes involved in bone catabolism and anabolism, indicating possible roles for mediators derived from arachidonic acid in the regulation of bone metabolism. These results suggest important therapeutic targets for early intervention in inflammatory diseases such as apical periodontitis to avoid resorption of bone tissue.

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Santos, Tatiane Souza dos [UNESP]. "Efeito de fitases de origem bacteriana no desempenho e qualidade óssea de frangos de corte." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/140152.

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Submitted by Tatiane Souza dos Santos null (tatianesouza7@hotmail.com) on 2016-06-30T14:20:04Z No. of bitstreams: 1 Dissertação Tatiane Final.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-30T19:06:01Z (GMT) No. of bitstreams: 1 santos_ts_me_bot.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) Made available in DSpace on 2016-06-30T19:06:01Z (GMT). No. of bitstreams: 1 santos_ts_me_bot.pdf: 1307496 bytes, checksum: 89e3b2f7bd2c32edaab8538b65c7914f (MD5) Previous issue date: 2016-06-24 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Este estudo objetivou avaliar o efeito de três fitases comerciais derivadas da Escherichia coli, em dietas com níveis reduzidos de fósforo disponível, sobre o desempenho, fosfatase alcalina e ácida no soro, cálcio e fósforo no plasma e nos parâmetros ósseos (densitometria óssea, resistência óssea e cinzas) de frangos de corte aos 35 dias de idade. Dois mil e cem pintos machos de um dia de idade da linhagem Cobb®500 foram alojados em 70 boxes em delineamento experimental inteiramente casualizado em esquema fatorial, criados até 35 dias de idade dividido em fase inicial (I) e fase de crescimento (C). Nos tratamentos Controle positivo*(CP*) e Controle negativo*(CN*) foi praticada a valorização nutricional da fitase preconizada pelos fabricantes (0,12% Pd) em relação aos tratamentos Controle positivo (CP) e Controle negativo (CN). O esquema fatorial foi 2x4+2: dois níveis de fósforo disponível (Pd) (CP* - 0,33% (I) e 0,28% (C)) e (CN* - 0,23% (I) e 0,18% (C)) × fitases (A, B, C, ausente) + CP (0,45 (I) e 0,40% (C) Pd, sem fitase) e CN (redução de 0,10% de Pd: 0,35 (I) e 0,30% (C) Pd, sem fitase) totalizando 10 tratamentos com sete repetições. A ausência de fitase na dieta CN* promoveu os piores resultados para desempenho e qualidade óssea, além de elevar o nível de fosfatase alcalina e cálcio no sangue como resposta ao baixo nível de fósforo disponível na dieta. A inclusão de fitases nas dietas CP* melhorou o desempenho, com maior disponibilidade de minerais para o desenvolvimento ósseo. Desta forma, a densidade óssea da tíbia e do fêmur aumentaram, proporcionando ossos mais resistentes e com maior porcentagem de cinzas. Recomenda-se, quando da utilização das fitases para frangos de corte, utilizar apenas a valorização nutricional da enzima (-0,12% Pd), sem redução adicional de fósforo disponível nas dietas. This study aimed to evaluate the effect of three commercial phytases derived from Escherichia coli, in diets with reduced levels of available phosphorus, on performance, alkaline and acid phosphtases in serum, calcium and phosphorus in plasma and bone parameters (bone density, bone strength and ash) of broilers at 35 d old. Two thousand one hundred male Cobb®500 broilers were housed in 70 pens in a completely randomized design in factorial arrangement, reared to 35 d old divided into starter phase (I) and the grower phase (G). In treatments positive control* (PC*) and negative control*(NC*) was practiced nutritional value of phytase recommended by the manufacturer (0.12% aP) in relation to positive control (PC) and negative control (NC) treatments. The factorial design was 2x4+2: two levels of available phosphorus (aP) (PC* - 0.33% (S) and 0.28 % (G)) and (NC* - 0.23% (S) and 0.18% (G)) × phytases (A, B, C, without) + PC (0.45 (S) and 0.40% (G) aP without phytase) and NC (decrease of 0.10 of aP: 0.35 (S) and 0.30% (G) aP without phytase) for a total 10 treatments with seven replicates. The absence of phytase in the diet NC* promoted the worst results for performance and bone quality, and increased the level of alkaline phosphatase and calcium in the blood in response to low levels of available phosphorus in diet. The inclusion of phytase in diets PC* improve the performance and increased availability of minerals for bone development. Thus, increased the bone density of the tibia and femur, bone strenght and bone ash. It is concluded that the inclusion phytase in diets PC* was sufficient to ensure good performance and bone quality. It is recommended, while the use of phytases for broiler use only the nutritional value of phytase (-0.12% aP) without additional reduction of available phosphorus in the diets. FAPESP: 2014/27175-8

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Santos, Tatiane Souza dos. "Efeito de fitases de origem bacteriana no desempenho e qualidade óssea de frangos de corte." Botucatu, 2016. http://hdl.handle.net/11449/140152.

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Orientador: José Roberto Sartori Resumo: Este estudo objetivou avaliar o efeito de três fitases comerciais derivadas da Escherichia coli, em dietas com níveis reduzidos de fósforo disponível, sobre o desempenho, fosfatase alcalina e ácida no soro, cálcio e fósforo no plasma e nos parâmetros ósseos (densitometria óssea, resistência óssea e cinzas) de frangos de corte aos 35 dias de idade. Dois mil e cem pintos machos de um dia de idade da linhagem Cobb®500 foram alojados em 70 boxes em delineamento experimental inteiramente casualizado em esquema fatorial, criados até 35 dias de idade dividido em fase inicial (I) e fase de crescimento (C). Nos tratamentos Controle positivo*(CP*) e Controle negativo*(CN*) foi praticada a valorização nutricional da fitase preconizada pelos fabricantes (0,12% Pd) em relação aos tratamentos Controle positivo (CP) e Controle negativo (CN). O esquema fatorial foi 2x4+2: dois níveis de fósforo disponível (Pd) (CP* - 0,33% (I) e 0,28% (C)) e (CN* - 0,23% (I) e 0,18% (C)) × fitases (A, B, C, ausente) + CP (0,45 (I) e 0,40% (C) Pd, sem fitase) e CN (redução de 0,10% de Pd: 0,35 (I) e 0,30% (C) Pd, sem fitase) totalizando 10 tratamentos com sete repetições. A ausência de fitase na dieta CN* promoveu os piores resultados para desempenho e qualidade óssea, além de elevar o nível de fosfatase alcalina e cálcio no sangue como resposta ao baixo nível de fósforo disponível na dieta. A inclusão de fitases nas dietas CP* melhorou o desempenho, com maior disponibilidade de minerais para o desenvolviment... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: This study aimed to evaluate the effect of three commercial phytases derived from Escherichia coli, in diets with reduced levels of available phosphorus, on performance, alkaline and acid phosphtases in serum, calcium and phosphorus in plasma and bone parameters (bone density, bone strength and ash) of broilers at 35 d old. Two thousand one hundred male Cobb®500 broilers were housed in 70 pens in a completely randomized design in factorial arrangement, reared to 35 d old divided into starter phase (I) and the grower phase (G). In treatments positive control* (PC*) and negative control*(NC*) was practiced nutritional value of phytase recommended by the manufacturer (0.12% aP) in relation to positive control (PC) and negative control (NC) treatments. The factorial design was 2x4+2: two levels of available phosphorus (aP) (PC* - 0.33% (S) and 0.28 % (G)) and (NC* - 0.23% (S) and 0.18% (G)) × phytases (A, B, C, without) + PC (0.45 (S) and 0.40% (G) aP without phytase) and NC (decrease of 0.10 of aP: 0.35 (S) and 0.30% (G) aP without phytase) for a total 10 treatments with seven replicates. The absence of phytase in the diet NC* promoted the worst results for performance and bone quality, and increased the level of alkaline phosphatase and calcium in the blood in response to low levels of available phosphorus in diet. The inclusion of phytase in diets PC* improve the performance and increased availability of minerals for bone development. Thus, increased the bone density of the ti... (Complete abstract click electronic access below) Mestre

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Awori, Ryan Musumba [Verfasser], Helge Björn [Gutachter] Bode, and Jörg [Gutachter] Soppa. "Nematophilic bacteria as a source of novel macrocyclised antimicrobial non-ribosomal peptides / Ryan Musumba Awori ; Gutachter: Helge Björn Bode, Jörg Soppa." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2021. http://d-nb.info/1234060469/34.

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SANTOS, Rogério William. "Isolamento e Caracterização de Cepas Shewanella Sp. Do Cultivo Heterotrófico de Litopenaeus Vannamei (Boone, 1931)." Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/15667.

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Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-03-04T16:25:51Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Roger Dissertação Mestrado 2014_ versão Final biblioteca_ Entregue_.pdf: 1359994 bytes, checksum: ce3bbcf3906e6cb72bdfea9a7b7e7d06 (MD5) Made available in DSpace on 2016-03-04T16:25:51Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Roger Dissertação Mestrado 2014_ versão Final biblioteca_ Entregue_.pdf: 1359994 bytes, checksum: ce3bbcf3906e6cb72bdfea9a7b7e7d06 (MD5) Previous issue date: 2014-02-20 CAPES CNPq FINEP O gênero Shewanella é um representante da classe das Gammaproteobactérias, família Shewanellaceae, compondo um grupo de bactérias gram-negativas, móveis, baciliforme, oxidase positiva, comumente encontrada em ambiente marinho e isolada do trato digestivo de animais aquáticos. Devido a suas características vem sendo amplamente testado como probiótico na carcinicultura. Estes têm sido utilizados na aquicultura para o controle biológico, aumento da taxa de conversão alimentar e sistema imune dos camarões. Este estudo teve por objetivo identificar potenciais bactérias probióticas retiradas do hepatopâncreas e estômago do camarão cultivado em sistema heterotrófico, avaliar as relações filogenéticas das cepas com o gênero Shewanella e caracteriza-las através de análisesmorfológicas, bioquímicas, produção de biofilme e antibiograma. A partir do cultivo heterotrófico de Litopenaeus vannamei, foram selecionadas as cepasIPA-S.51, IPA-S.111 e IPA-S.252para identificação através do sequenciamento parcial do gene 16S rRNA e comparados ao GenBank – NCBI e RDP - Seqmatch. As cepas foram alinhadas a 45 espécies do gênero Shewanella e avaliadas filogeneticamente utilizando os métodos Neighbor-Joining, Máxima Verossimilhança e Inferência Bayesiana. Quanto àsanálises morfológicas foram avaliadas parâmetros de acordo com a similaridade a padrões estabelecidos. Os testes bioquímicos foram realizados com o auxílio dos kits BACTRAY I, BACTRAY II e BACTRAY III (Labroclin®), totalizando 30 testes bioquímicos. A avaliação da capacidade de formação de biofilme foi realizada segundo Christensen e colaboradores. No antibiograma as cepas bacterianas foram submetidas a 13 antibióticos distintos segundo à técnica de Kirby e Bauer, com três repetições. O sequenciamento das cepas revelou alta similaridade a espécie Shewanella algae, utilizando o GenBank e o RDP-seqmath. A Inferência Bayesiana apresentou maior aporte estatístico e fidelidade dentre os métodos analisados. A Shewanella upenei apresentou alta similaridade as cepas estudadas, assim como a S. algae. As análises filogenéticas não descartam a hipótese de novas espécies para IPA-S.51, IPA-S.111 e IPAS. 252. As cepas estudadas foram sensíveis aos antibióticos Ampicilina/Subactan, Ofloxacina e Tetraciclina. A caracterização fenotípica fortalece a hipótese de especiação para as cepas testadas. Portanto, a capacidade de formação de biofilme, adicionada ao alto potencial enzimático e antagonismo a patógenos, característico do gênero Shewanella, tornam estas cepas potenciais probióticos para carcinicultura. The genus Shewanella is one representant of Gammoproteobacteria class, family Shewanellaceae, being part of gram-negative bacteria group, mobile, bacilliform, oxidasepositive, commonly found on marine environments and isolated from the digestive tract of aquatic animals. Due to its characteristics, some tests as probiotics are being carried out in carciniculture. They are being used on aquaculture for biological control, augmentations on feed conversion rates and immune system of shrimps. This study has as objective identify potentials probiotics bacteria found in the hepatopancreas and stomach of shrimps cultivated on heterotrophic based system, evaluating the strain phylogenetic relationships with Shewanella genus and characterizing them through morphological and biochemical analysis, biofilm production and antibiogram. The strains IPA-S.51, IPA-S.111 e IPA-S.252 were selected from the heterotrophic cultivation of Litopenaeus vannamei, identified through partial 16S rRNA sequencing and compared to GenBank – NCBI and RDP - Seqmatch.The strains were aligned to 45 species of Shewanella genus and phylogenetically evaluated using Neighbor-Joining,Maximum-Likelihood estimation and Bayesian Inference.Regarding the morphological analysis parameters were evaluated according with established standard similarities. The biochemical tests were conducted with the assistance of BACTRAY I, BACTRAY II and BACTRAY III (Labroclin®) kits, totalizing 30 biochemical tests.The Biofilm capacity evaluation was made according Christensen et al. Regarding the antibiogram, the bacterial strains had undergone 13 distinct antibiotics according Kirby and Bauer, with three repetitions. The strains sequencing showed high similarity to Shewanella algae species, using GenBank and RDP-seqmath.The Bayesian inference displayed higher statistic contribution e fidelity among the other methods.The Shewanella upenei showed high similarity to the strains in study also as Shewanella algae.The phylogenetic analysis does not exclude the hypothesis of IPA-S.51, IPA-S.111 e IPA-S.252 being new species.The strains studied were sensitives to the antibiotics Ampicillin/Sulbactam, Ofloxacin, Tetracyclin. The phenotypic characterization of the strains supports the hypothesis of speciation. Thus, the capacity of biofilm formation plus the high enzymatic potential and antagonism interactions to pathogens, characteristics found in the Shewanella genus, make these strains potential probiotics to carciniculture.

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Pérez, Alexander José [Verfasser], Helge B. [Akademischer Betreuer] Bode, and Joachim W. [Akademischer Betreuer] Engels. "Tracking of bacterial metabolism with azidated precursors and click-chemistry / Alexander José Pérez. Gutachter: Helge B. Bode ; Joachim W. Engels." Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2016. http://d-nb.info/1081718528/34.

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Jacob, Megan E. "Effects of diets, antimicrobials and minerals on the revalence and antimicrobial susceptibility of fecal bacteria in feedlot cattle." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/442.

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Pereira, Yamba Carla Lara. "Avaliação in vivo e in vitro do efeito do extrato de própolis em osso alveolar, com e sem contaminação de lipopolissacarídeo bacteriano." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/58/58137/tde-04022011-154946/.

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A própolis é uma substância resinosa, cujas atividades antibacteriana, antiinflamatória, antiviral, fungicida, imuno estimulante, cicatrizante e de anestésico local tem sido valorizadas no uso clínico. O lipopolissacarídeo (LPS) é reconhecidamente uma endotoxina e pode induzir processos inflamatórios. Os objetivos deste trabalho foram: a) analisar in vitro as seguintes propriedades do extrato de própolis verde: 1) perfil físico químico 2) Concentração Inibitória Mínima (CIM) frente à endotoxina da bactéria gram negativa Escherichia coli; e 3) sua atividade imunorregulatória sobre leucócitos de baço de ratos; b) analisar ″in vivo″ a ação do Extrato Etanólico de Própolis (EEP) 10% e 90% e do Extrato de Própolis Puro (EPP), em alvéolos dentais contaminados ou não com lipopolissacarídeo (LPS) bacteriano. Para o estudo in vivo 35 ratos foram submetidos às exodontias dos primeiros molares superiores direito e esquerdo, os quais, imediatamente tiveram o alvéolo dental direito contaminado com 0,1µL de lipopolissacarídeo (LPS) (100µg/kg) e o esquerdo sem tal contaminação. Os grupos com (n=7) para cada tratamento, após 2 semanas: GI- Controle Negativo (CN) - sem tratamento; GII- Tratados com Extrato de Própolis puro (EPP) GIII- Tratados com pasta de própolis a 90% (P90); GIV- Tratados com pasta de própolis a 10% (P10); e, GV- Tratado com veículo das pastas (SB) foram analisados. Os alvéolos foram removidos, desmineralizados, processados pela técnica histológica de rotina, submetidos a secções sistematizadas a 6 µm de espessura e corados em H.E. O volume de osso formado, foi avaliado por contagem de pontos, usando um Sistema Teste sobreposto as imagens capturadas com auxílio de uma câmera acoplada a um microscópio. Observada a normalidade dos dados, procedeu-se o teste ANOVA fatorial e Tukey-Kramer test (p<0,05). In vitro determinou-se a propriedade da própolis, sua CIM e atividade imunorregulatória. In vivo os alvéolos dentais contaminados com lipopolissacarídeo bacteriano e tratados com a própolis verde apresentou maior área de osso neoformado, quando comparado aos demais grupos experimentais. O alvéolo não contaminado e tratado com própolis pura mostrou maior área de fibras colágenas. Propolis is a resinous substance, whose antibacterial, antiinflammatory, antiviral, antifungal, immune stimulant, and local anesthetic wound healing properties has been considered for clinical practice. The lipopolysaccharide (LPS) is recognized as an endotoxin and can induce inflammatory processes. Our objectives were: a) to analyze in vitro the following properties of green propolis extract: 1) physicochemical profile of green propolis sample, 2) Minimum Inhibitory Concentration (MIC) against endotoxin from gram negative Escherichia coli and 3) its immunoregulatory activity using leukocytes from the spleen of mice,. b) analyze in vivo, the action of propolis ethanol extract (EEP) 10% and 90% and Pure Propolis Extract (EPP) in dental alveoli or not contaminated with lipopolysaccharide (LPS) bacterial. For in vivo study, 35 rats were subjected to extractions of maxillary first molars, right and left, which immediately had the right dental socket contaminated with 0.1 µL of lipopolysaccharide (LPS) (100µg/kg) and left without such contamination. They were divided into groups (n = 7) for each sample after 2 weeks, according to the treatment in the right and left alveoli: GI-Negative Control (NC) - no treatment, GII-Treated Pure Propolis Extract (EPP) GIII-Treated folder with propolis 90% (P90), GIV-Treated folder with propolis 10% (P10) and GV-Treated folder with vehicle (SB). The alveoli were removed, demineralized, processed by routine histologic technique, submitted to systematic sections (6 microns) of thick and stained with HE for histological analysis to assess the new bone tissue volume by point counting method, using a Test system on images captured with the aid of a digital camera attached to a microscope. Observed data normality, we proceeded to ANOVA and Tukey-Kramer tests (p <0.05). In vitro, it was determined the propolis properties, CIM and immunoregulatory activity. In vivo, the alveoli contamined with bacterian lipopolysaccharide and treated with green propolis induced higher bone formation when compared to other groups. The non contamined alveoli and treated with pure propolis showed more quantity of collagen fibers.

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Coelho, Fernanda. "Desenvolvimento, avaliação da toxicidade e do potencial reparador ósseo de materiais à base de fibroína ou celulose bacteriana associados à hidroxiapatita e anticorpos anti-bmp-2 /." Araraquara, 2018. http://hdl.handle.net/11449/153326.

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Orientador: Ticiana Sidorenko de Oliveira Capote Resumo: A engenharia tecidual voltada ao tecido ósseo tem como objetivo proporcionar uma reparação que apresente propriedades físicas e biológicas similares ao osso natural com restabelecimento adequado das suas funções. Neste contexto, materiais aloplásticos baseados em biopolímeros como a fibroína da seda (FS) e celulose bacteriana (CB) têm proporcionado a síntese de excelentes biomateriais para reparação óssea. Esses biopolímeros são biocompatíveis, possuem características mecânicas interessantes, apresentam uma lenta taxa de degradação in vivo, além da capacidade de serem modificados quimicamente. Para conferir a estes biopolímeros uma melhor bioatividade com intuito de potencializar a eficácia local da reparação óssea, o objetivo do presente estudo consistiu em sintetizar uma membrana à base de FS e outra à base de CB, sendo cada uma associada à hidroxiapatita e anticorpo anti-proteína morfogenética óssea (anti-BMP-2). Para tanto, estas membranas foram caracterizadas físico-quimicamente e, para análise do potencial destas membranas na reparação óssea, foram realizados ensaios in vitro para investigação de citotoxicidade, genotoxicidade e mutagenicidade, além de expressão gênica desses materiais. As membranas à base de CB obtiveram resultados da caracterização físico-quimicamente mais satisfatórios em relação à FS e os testes seguintes foram realizados apenas com a membrana de CB. A membrana de CB associada à hidroxiapatita não demonstrou citotoxicidade, genotoxicidade e mutageni... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: Tissue engineering related to the bone tissue aims to provide a repair that presents similar physical and biological properties to the natural bone with adequate restoration of its functions. In this context, alloplastic materials based on biopolymers such as silk fibroin (SF) and bacterial cellulose (BC) have provided the synthesis of excellent biomaterials for bone repair. These biopolymers are biocompatible, have interesting mechanical characteristics, have a slow rate of degradation in vivo, and the ability to be chemically modified. In order to give these biopolymers better bioactivity to potentiate the local effectiveness for bone repair, the aim of the present study was to synthesize a SF-based and BC-based membrane, each of them was associated with hydroxyapatite and antibody anti-bone morphogenetic protein (anti-BMP-2). The membranes with immobilized anti-BMP-2 are expected to be effective in capturing endogenous BMP-2, conferring a different therapeutic approach and potential use for bone tissue engineering. For this purpose, these membranes were physico-chemically characterized and, in order to analyze the potential of these membranes in bone repair, in vitro assays were performed to investigate cytotoxicity, genotoxicity, mutagenicity and gene expression of these materials. The BC-based membranes obtained physically-chemically characteristics more satisfactory than the SF, and the next tests were performed only on the BC membrane. The BC membrane associated with h... (Complete abstract click electronic access below) Mestre

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VIDAL, Juliana Maria Aderaldo. "Bactérias com potencial probiótico isoladas do intestino de camarão marinho Litopenaeus vannamei (Boone, 1931)." Universidade Federal Rural de Pernambuco, 2015. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6549.

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Submitted by (edna.saturno@ufrpe.br) on 2017-02-23T14:03:29Z No. of bitstreams: 1 Juliana Maria Aderaldo Vidal.pdf: 784041 bytes, checksum: f927beb63f5c3c304d4098214b0dd629 (MD5) Made available in DSpace on 2017-02-23T14:03:29Z (GMT). No. of bitstreams: 1 Juliana Maria Aderaldo Vidal.pdf: 784041 bytes, checksum: f927beb63f5c3c304d4098214b0dd629 (MD5) Previous issue date: 2015-07-27 Bacteria with probiotic effect have been used in marine shrimp production like antibiotics substitution, contributing to the health of the host, by antagonistic action to pathogenic micro-organisms or by competition for space and nutrients, and improving appetite and lead the further growth of the animals. When isolated from the host itself is safe to use, being able to adhere and colonize the intestine. The objective was to isolate probiotic bacteria from intestine of juvenile Litopenaeus vannamei and evaluate the effects of probiotic administration in the performance of cultivated animals experimental challenged infection. Intestinal bacteria were from cultivated shrimp in oligohaline water and saltwalter in dry and rainy seasons, and confronted with Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus and Aeromonas hydrophila. Bacteria showed antimicrobial effect have been identified by molecular biology. Twenty-nine isolates showed antagonistic effect at least one of the tested pathogens. The species that most occurred was Bacillus cereus, the producing of the largest zones of inhibition to the V. alginolyticus and V. vulnificus. The bacterium Citrobacter freundii, from oligohaline water showed the best antimicrobial effect before the four pathogens. The probiotic Bacillus cereus was tested in diet for marine shrimp post-larvae against challenge with V. parahaemolyticus, and V. alginolyticus which evaluated the growth performance of animals, colonization capacity of the probiotic bacteria, pathogens count and histopathological lesions. The use of probiotic had no effect on animals survival, but not for treatments which was used probiotic had a lower weight gain. Animals fed dietary supplementation of probiotic had lower pathogens count those fed without the use. Histopathological lesions were observed in organs and tissues of animals. It can be concluded that it was possible to isolate bacteria having probiotic effect of marine shrimp intestine, wherein the strain Bacillus cereus demonstrated high capacity to colonize the host itself, causing a significant reduction of pathogens. Bactérias com efeito probiótico contribuem para saúde de camarões marinhos em cultivo, em substituição aos antibióticos, exercendo ação antagonista à micro-organismos patogênicos ou por competição por espaço e nutrientes, além de melhorar o apetite levando a um maior crescimento dos animais. Quando isolados do próprio camarão seu uso é seguro, por serem capazes de aderir ou colonizar o intestino destes. Neste sentido, objetivou-se isolar bactérias probióticas do intestino de juvenis de Litopenaeus vannamei e avaliar os efeitos da sua administração sobre o desempenho dos animais cultivados frente infecção experimental. Foram isoladas bactérias do intestino de camarão cultivado em águas oligohalina e salgada, em períodos seco e chuvoso, e confrontadas com Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus e Aeromonas hydrophila, em testes in vitro. As bactérias que produziram efeito antimicrobiano foram identificadas através de biologia molecular.Vinte e nove isolados apresentaram efeito antagônico a pelo menos um dos patógenos testados. A espécie que mais ocorreu foi Bacillus cereus, produzindo os maiores halos de inibição frente ao V. alginolyticus e V. vulnificus. A bactéria Citrobacter freundii, proveniente de água oligohalina apresentou melhor efeito antimicrobiano, perante os quatro patógenos. O probiótico Bacillus cereus foi testado em ração para pós-larvas de L. vannamei, frente a desafio com V. parahaemolyticus, e V. alginolyticus quando avaliou-se o desempenho zootécnico dos animais, a capacidade de colonização das bactérias probióticas, contagem de patógenos e lesões histopatológicas. O uso do probiótico não influenciou nas taxas de sobrevivência dos animais, porém nos tratamentos em que não se utilizou probiótico houve menor ganho de peso. Os animais que receberam ração suplementada de probiótico, tiveram contagem de patógenos inferior aqueles alimentados sem o uso. Não foram observadas lesões histopatológicas nos órgãos e tecidos dos animais. Concluiu-se que é possível isolar bactérias com efeito probiótico do intestino do camarão marinho, sendo que a cepa de Bacillus cereus demonstrou maior capacidade de colonizar o próprio hospedeiro, diminuindo os patógenos.

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Ferreira, Sara Cristina Silva. "Novos biomateriais poliméricos para implantes ósseos." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16828.

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Mestrado em Bioquímica - Bioquímica Clínica Os danos dos tecidos ósseos representam um problema importante de saúde em todo o mundo. Um dos componentes principais utilizados em engenharia de tecidos são os materiais de suporte, estruturas 3D formadas por matrizes porosas, que visam proporcionar o desenvolvimento do novo tecido. Muitas das matrizes poliméricas porosas (espumas) utilizadas em aplicações médicas são constituídas por poliuretanos, sendo estes produzidos a partir de isocianatos (produtos tóxicos) e polióis. Assim, surge a necessidade de desenvolver novos biomateriais poliméricos porosos com base em materiais não-tóxicos e em metodologias amigas do ambiente. Desta forma, o objetivo deste trabalho consistiu no desenvolvimento de novos biomateriais porosos, por polimerização radicalar em emulsão de Pickering. Emulsão, esta, constituída por água-em-óleo de soja epoxidado acrilatado e estabilizada com nanocelulose bacteriana. Os materiais resultantes (polyMIPES) foram caraterizadas detalhadamente em termos estruturais, morfológicos e quanto às suas propriedades mecânicas. Os resultados obtidos permitiram concluir que a a utilização do monómeros de divinilbenzeno (DVB) as melhora significativamente as propriedades mecânicas das espumas, sendo que poderão ser bons candidatos a materiais de suporte. As espumas obtidas apresentam poros cujos valores médios variam entre 268,20 ± 30,27 e 356,60 ± 40,03 μm, boas propriedades termomecânicas (Tg entre 43ºC e 50ºC e temperaturas de degradação inicial por volta dos 250º C), e ainda módulos de Young elevados de ≈11,41±0,86 e ≈13,15±0,75 MPa. Bone tissues damage represents a significant health problem all over the world. Scaffolds, 3D structures formed by porous matrices that provides the new tissue’s development, are one of the main components used in tissue engineering. Most of the porous polymeric matrices (foams) used in medical applications are made by polyurethanes, which are produced from isocyanates (toxic products) and polyols. Hence, there is a need in the development of new porous polymeric biomaterials based on non-toxic materials and environmentally friendly methodologies. Thus, the objective of this work is to develop new porous biomaterials, by Pickering emulsion radical polymerization. This will be a w/o emulsion using bacterial nanocellulose fragments as Pickering emulsion stabilizers and the oil phase shall be composed by acrylated epoxidised soybean oil. The obtained foams (PolyMIPES) were characterized structurally, morphologically and regarding their mechanical properties. The results allow us to conclude that the use of divinylbenzene (DVB) monomers on the preparation of the foams highly improve their mechanical properties; and therefore these foams are good candidates to be used as scaffolds. These foams have good thermomechanical properties (Tg between 43ºC-50ºC and initial degradation temperatures around 250ºC). The porous size are in the range 268,20 ± 30,27 and 356,60 ± 40,03 μm and present high Young’s modulus: ≈11,41±0,86 e ≈13,15±0,75 MPa.

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LIMA, João Paulo Viana de. "Utilização de melaço como fonte de carbono em cultivo do camarão branco do Pacífico Litopenaeus vannamei (Boone,1931) sem renovação de água e sob diferentes relações carbono/nitrogênio." Universidade Federal Rural de Pernambuco, 2007. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6344.

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Submitted by (edna.saturno@ufrpe.br) on 2017-02-14T15:59:47Z No. of bitstreams: 1 Joao Paulo Viana de Lima.pdf: 751024 bytes, checksum: 12aea5280a52c50190be7cbe5d4985dc (MD5) Made available in DSpace on 2017-02-14T15:59:47Z (GMT). No. of bitstreams: 1 Joao Paulo Viana de Lima.pdf: 751024 bytes, checksum: 12aea5280a52c50190be7cbe5d4985dc (MD5) Previous issue date: 2007-04-27 The accumulation of toxic nitrogenous compounds in the water is a common problem to aquaculture systems. Recent works have showed good results in terms of production and nitrogen retention efficiency, through the addition of organic carbon source (sugar, molasses, etc). This work investigated the effect of molasses addition in different C:N ratios on the water quality, microbial activity and production, in semi-intensive experimental culture tanks of Litopenaeus vannamei with no water exchange. Four treatments and three replicates were adopted, which three with daily molasses addition in 5, 10 and 15:1 C:N ratio and one control with no carbon source addition. Twelve 500 L fiber glass tanks were stocked with 25 shrimps.m-2 (1.90±0.37 g). Shrimps were fed with a 35% crude protein commercial diet offered in feeding trays at 08:00 and 16:00. Phytoplankton, bacteria and water samples were collected fortnightly during the culture. The 15:1 and 10:1 C:N ratios showed lower (P<0.05) oxygen dissolved levels (4.64 and 4.76 mg L-1, respectively) which is related with the major organic carbon supply in these ratios. Molasses addition resulted in lower (P<0.05) nitrogenous compounds levels (nitrite and nitrate), as well reducing in the cianobacteria densities in the C:N 10 and 15:1 treatments. No significant differences (P≥0.05) were found in Vibrio spp, autotrophic and heterotrophic bacterial densities. Shrimp final weight (~12.3 g)and weigth gain (~1.04 g.week-1) in high C:N ratios (10:1 and 15:1) were higher (P<0.05) than in the others treatments. Specific growth rate was high in all treatments (2.53 to 2.69 % day-1), but the 10:1 ratio was higher than the control. Yield values ranged from 267.4 to 301.0 g m-2 with no significant difference (P≥0.05) among treatments. This study shows that the molasses can be used as carbon source in order to increase C:N ratio, improving the water quality and the L. vannamei semi-intensive culture performance with no water exchange. O acúmulo de formas tóxicas de compostos nitrogenados na água é um grande problema para os sistemas aqüícolas. Pesquisas recentes têm demonstrado resultados satisfatórios em termos de produção e eficiência de retenção do nitrogênio, através da adição de fontes de carbono orgânico (açúcar, melaço, etc.). O presente estudo investigou o efeito da adição de melaço em diferentes relações C:N sobre a qualidade da água, atividade microbiana e a produção semi-intensiva do camarão Litopenaeus vannamei, em tanques de cultivo experimental sem renovação de água. Foram adotados quatro tratamentos e três réplicas, sendo três com aplicação diária de melaço nas relações C:N 5, 10 e 15:1, e um controle, sem aplicação desta fonte de carbono. Foram utilizados 12 tanques em fibra de vidro (500 L), estocados com 25 camarões.m-2 (1,90±0,37 g). A alimentação constou de ração comercial com 35% de proteína bruta e foi ofertada diariamente em bandejas às 8 e 16h. Coletas de água para análise química e de material biológico (fitoplâncton e bactérias) foram realizadas quinzenalmente ao longo do cultivo. As relações 15:1 e 10:1 apresentaram os menores (P<0,05) níveis de oxigênio dissolvido (4,64 e 4,76 mg L-1, respectivamente) que está relacionado ao maior aporte de carbono orgânico nestas relações. O melaço reduziu significativamente (P<0,05) as concentrações dos compostos nitrogenados, nitrito e nitrato, bem como reduziu as densidadesde cianobactérias nos ambientes com relações C:N de 10 e 15:1. Nenhum efeito (P≥0,05) foi observado em relação às bactérias autotróficas, heterotróficas e Vibrio spp. O peso final dos camarões (~12,3 g) e o ganho de peso individual (~1,04 g.semana-1), nas relações C:N mais altas (10:1 e 15:1), foram superiores (P<0,05) aos demais tratamentos. A taxa de crescimento específico foi elevada em todos os tratamentos (2,53 a 2,69 % dia-1), entretanto os indivíduos na relação 10:1 foi superior (P<0,05) ao controle. Os valores de produção variaram de 267,4 a 301,0 g m-2, e não foram diferentes estatisticamente (P≥0,05) entre os tratamentos. O melaço pode ser utilizado como fonte de carbono para incrementar a relação C:N, melhorando a qualidade da água e os níveis de produtividade em cultivo semi-intensivo de L. vannamei sem renovação de água.

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Nilsson, Ingrid. "Studies of immune responses to cell surface proteins of Helicobacter pylori and Borrelia burgdorferi by enzyme imunoassay and immunoblotting." Lund : Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/68945022.html.

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Rego, Mariana Ribeiro de Moraes. "Remodelação alveolar e perfil bacteriano em implantes instalados em diferentes níveis relacionados à crista óssea." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7432.

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A substituição clínica de dentes naturais perdidos por implantes osteointegrados tem representado uma das primeiras opções terapêuticas para a reabilitação de pacientes total ou parcialmente edêntulos. Apesar dos excelentes índices de sucesso demonstrados pelas restaurações implanto-suportadas, alguns fatores permanecem não esclarecidos, principalmente no que diz respeito à remodelação óssea ao redor dos implantes osteointegrados. Desta forma, o objetivo deste estudo foi avaliar a relação do nível de instalação dos implantes dentários com os parâmetros clínicos, com a remodelação óssea peri-implantar e com a colonização bacteriana, em implantes de plataforma regular, submetidos à carga imediata. Implantes de plataforma regular foram instalados em dois diferentes níveis em relação à crista óssea ao nível ósseo e supra ósseo (1 mm). No total, trinta e cinco implantes em 9 pacientes (idade média de 62,4 11,2 anos) foram avaliados radiograficamente no momento da instalação dos implantes (T1) e 6 meses após (T2), momento no qual também foram feitas análises clínicas e coleta de amostras para o teste microbiológico. Nos exames radiográficos foram analisadas a perda óssea, a partir de mensurações lineares da distância entre um ponto fixo do componente protético e o ponto mais coronário do contato osso-implante, e a densidade óptica alveolar obtida a partir de regiões ósseas de interesse (ROIs). As análises clínicas consistiram na avaliação da profundidade de sondagem e na mensuração do volume do fluido gengival peri-implantar. O perfil bacteriano dos sítios avaliados foi caracterizado por meio do método de análise de checkerboard DNA-DNA hybridization. Os testes estatísticos realizados mostraram não haver relação entre o nível de instalação dos implantes em relação à crista óssea e a remodelação óssea alveolar, tanto com relação à perda óssea (p = 0,725), como com relação à densidade óptica alveolar (p = 0,975). Também não foi possível estabelecer uma correlação entre a remodelação óssea e parâmetros clínicos como profundidade de sondagem e volume do fluido gengival peri-implantar. Com relação ao perfil bacteriano, não foram encontradas diferenças estatisticamente significativas entre os grupos avaliados para nenhuma das 40 bactérias analisadas. The replacement of missing teeth with osteointegrated dental implants represents one of the first therapeutic options for the rehabilitation of totally or partially edentulous patients. In spite of clinical success rates for implant-supported restorations, some factors remain nuclear, especially those related to alveolar bone remodeling around osteointegrated implants. Thus, the aim of this study was to evaluate the relation between the installation level of dental implants with bone remodeling and bacterial colonization, in regular platform implants, under an immediate loading protocol. Dental implants with regular platform were inserted in different levels related to the bone crest on the level of bone crest and above the bone crest. In total, thirty-five implants in 9 patients (mean age 62,4 11,2 years) were radiographically evaluated in the moment of implant installation (T1) and 6 months after (T2), when clinical analysis and sample collecting for microbiologic test were performed. In radiographic exams were analyzed the marginal bone loss, from linear measurements of the distance between a fixed point of prosthetic components and the most coronal point of bone-implant contact, and optical alveolar density, from bone regions of interest (ROIs). Clinical analysis consisted of probing depth evaluation and peri-implant crevicular fluid volume mensuration. The bacterial profile of selected sites was characterized by checkerboard DNA-DNA hybridization method. Statistic tests showed no relation between implant insertion levels and alveolar bone remodeling, with relation to marginal bone loss (p = 0,725) and optical alveolar density (p = 0,975). It was not also possible to establish a correlation among alveolar bone remodeling and clinical parameters as probing depth and peri-implant crevicular fluid volume. With respect to the bacterial profile, no statistically significant differences were found between the study groups, for none of the 40 bacterial specimens analyzed.

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Allen, Richard. "Using the polymerase chain reaction to determine the prevalence of Lyme Disease bacteria, Borrelia burgdorferi, in ixodes pacificus ticks from San Bernardino County in Southern California." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1748.

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The purpose of this study was to determine the prevalence of Lyme Disease (LD) bacteria in adult Ixodes pacificus ticks collected from the mountains of San Bernardino County in Southern California. Seven hundred fifty four I. pacificus adults were collected from the Pacific Crest Trail and adjacent areas. The Polymerase Chain Reaction (PCR) was used to screen ticks for Borrelia burgdorferi infection by targeting two different DNA loci. Oligonucleotide primers targeting both the ospA and fla genes were used in the assay. Ticks were processed in pools of three, and genomic DNA from the ticks was extracted with a commercial mini-kit utilizing silica matrix spin-columns. All ticks tested negative for B. burgdorferi infection regardless of primer pair used. In addition, ticks were negative following examination by dark-field microscopy. This study confirms previous reports that the prevalence of LD in Southern California is quite low.

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Bader, Kai Christian [Verfasser], Christian [Akademischer Betreuer] Grothoff, Burkhard [Akademischer Betreuer] Rost, and Arndt [Akademischer Betreuer] Bode. "High-performance approaches to the comprehensive computation and evaluation of signatures in bacterial sequence datasets / Kai Christian Bader. Gutachter: Burkhard Rost ; Arndt Bode ; Christian Grothoff. Betreuer: Christian Grothoff." München : Universitätsbibliothek der TU München, 2013. http://d-nb.info/1035274418/34.

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Dissertations / Theses on the topic 'Bacteria; Bone'

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