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Submitted by Carla Corrêa Mendes Gouvêa (carla_cmendes@hotmail.com) on 2018-06-07T14:56:34Z No. of bitstreams: 1 Tese corrigida Carla Correa Mendes Gouvêa.pdf: 2438125 bytes, checksum: 89f73cd540d3d9b9bbdf46167a4ca374 (MD5) / Approved for entry into archive by Ana Paula Rimoli de Oliveira null (anapaula@foa.unesp.br) on 2018-06-07T18:14:52Z (GMT) No. of bitstreams: 1 gouvea_ccm_dr_araca_int.pdf: 2438125 bytes, checksum: 89f73cd540d3d9b9bbdf46167a4ca374 (MD5) / Made available in DSpace on 2018-06-07T18:14:52Z (GMT). No. of bitstreams: 1 gouvea_ccm_dr_araca_int.pdf: 2438125 bytes, checksum: 89f73cd540d3d9b9bbdf46167a4ca374 (MD5) Previous issue date: 2018-05-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste estudo foi sintetizar e caracterizar nanocompósitos formados por polifosfatos (trimetafosfato de sódio (TMP) ou hexametafosfato de sódio (HMP)) e flúor (F) associados à nanopartículas de prata. Esses nanocompósitos foram avaliados quanto à sua ação anti-biofilme de Candida albicans (ATCC 10231) e Streptococcus mutans (ATCC 25175) e seu potencial em inibir a desmineralização do esmalte dentário por meio de ensaio in vitro de ciclagem de pH. As nanopartículas de prata foram sintetizadas através da redução do nitrato de prata (1 ou 10%) pelo borihidreto de sódio (NaBH4) em meio isopropílico contendo trimetafosfato de sódio (TMP) ou hexametafosfato de sódio (HMP)) e flúor (F). Os nanocompósitos foram caracterizados por microscopia eletrônica de varredura (MEV) e por difração de raios-X, e também determinada a concentração inibitória mínima (MIC) contra células planctônicas de C. albicans e S. mutans. A efetividade contra biofilmes pré-formados de 24h dos nanocompósitos, foi testada em concentrações de 1x e 10x os valores de MIC (de 40μg Ag ml−1), avaliada através da quantificação de células cultiváveis (CFUs), da atividade metabólica (XTT) e da biomassa total (Cristal Violeta). Os nanocompósitos contendo 10% de Ag apresentaram maior efetividade antimicrobiana contra ambos os microrganismos, comparados aos nanocompósitos contendo 1% de prata. O biofilme de S. mutans foi mais suscetível aos nanocompósitos TMP ou HMP/AgNP que o biofilme de C. albicans, com reduções respectivas de 2,88-3,71 log10 e 0,45-1,43 log10. Os nanocompósitos permitiram uma diminuição de cerca de 75% da biomassa total e em torno de 90% da atividade metabólica em ambos os biofilmes. Para avaliação in vitro do potencial anticárie, foi sintetizado um novo nanocompósito contendo 0,2% de TMP, 100 ppm de flúor e 10% de Ag e caracterizado por microscopia eletrônica de transmissão (MET). Blocos de esmalte bovino (4 mm x 4 mm, n = 60) selecionados pela dureza superficial inicial (SHi) foram alocados em cinco grupos (n = 12): água deionizada (Placebo), 100 ppm F (100F), 225 ppm F (225F), 100 ppm F + 0,2% TMP (100F/TMP) e 100 ppm F + 0,2% TMP + 10% Ag (100F/TMP/Ag). Os blocos foram tratados 2x ao dia com as soluções e submetidos a cinco ciclos de pH (soluções des e remineralizadora) à 37° C. Em seguida, determinou-se a dureza superficial final (SHf) e a dureza subsuperficial integrada (ΔKHN), e a concentração de fluoreto (F) e cálcio (Ca) no esmalte. A efetividade desse nanocompósisto (100F/TMP/Ag) contra a formação de biofilmes simples e misto de C. albicans (ATCC 10231) e S. mutans (ATCC 25175) foi avaliada por meio da contagem de unidades formadoras de colônias (CFUs). Os biofilmes foram também analisados por microscopia eletrônica de varredura (MEV). A dureza superficial (% SH) foi similar nas amostras tratadas com soluções contendo 225F, 100F/TMP e 100F/TMP/Ag (p> 0,001). Além disso, a capacidade de reduzir o corpo da lesão (ΔKHN) foi maior em 110F, 225F, 100F/TMP e 100F/TMP/Ag (p <0,001) na área A (5-20 μm) e na área B somente com 225F e 100F/TMP. O grupo 100F/ TMP/Ag apresentou maior desmineralização na área B (20-130 μm) (p <0,001). A concentração de F da solução 100F/TMP/Ag foi semelhante a 225F (p <0,001). Os grupos 100F, 225F, 100F/TMP e 100F/TMP/Ag apresentaram a maior e similar concentração de Ca (p> 0,001). A dureza superficial (% SH) foi similar nas amostras tratadas com soluções contendo 225F, 100F / TMP e 100F / TMP / Ag (p> 0,001). Além disso, a capacidade de reduzir o corpo da lesão (ΔKHN) foi maior em 110F, 225F, 100F / TMP e 100F / TMP / Ag (p <0,001) na zona A (5-20 μm) e na zona B apenas com 225F e 100F / TMP. O grupo 100F / TMP / Ag apresentou maior desmineralização na zona B (20-130 μm) (p <0,001). A concentração de F da solução 100F / TMP / Ag foi semelhante a 225F (p <0,001). Os grupos 100F, 225F, 100F / TMP e 100F / TMP / Ag apresentaram a maior e a mesma concentração de Ca (p> 0,001).Embora a solução 100F/TMP/Ag tenha apresentado valores mais baixos de áreas profundas do que a solução contendo 225 ppm F, o nanocompósito foi capaz de inibir a desmineralização da superfície do esmalte. Estes nanocompósitos demonstraram atividade antimicrobiana significativa, especialmente contra S. mutans, e podem ser considerados uma alternativa potencial para novos biomateriais odontológicos, visando a prevenção ou tratamento de lesões cariosas. / The aim of this study was to synthesize and characterize nanocomposites formed polyphosphates (sodium trimetaphosphate (TMP) or sodium hexametaphosphate (HMP)) and fluoride (F) associated with silv er nanoparticles. The anti - biofilm activity of the nanocomposites were evaluated against Candida albicans (ATCC ATCC 10231) and Streptococcus mutans (ATCC 25175) . as well as their potential in inhibiting demineralization and increasing the remineralizatio n of dental enamel by in vitro pH cycling assay. Silver nanoparticles were synthesized by reduction of silver nitrate (1 or 10%) by sodium bor ohydride (NaBH 4 ) in isopropylic medium containing sodium trimetaphosphate (TMP) or sodium hexametap hosphate (HMP)) and fluoride (F) . The nanocomposites were characterized by scanning electron microscopy (SEM) and X - ray diffraction. The minimum inhibitory concentration (MIC) of the nanocomposites was determined against planktonic cells of C. albicans and S. mutans . Eff ect iveness of preformed 24 - hour biofilms of nanocomposites at 1x and 10x MIC values was assessed by quantifying viable cells (CFUs), metabolic activity (XTT) and total biomass (Crystal Violet). The nanocomposites containing 10% Ag showed higher antimicrobia l effectiveness against both microorganisms compared to nanocomposites containing 1% silver. The S. mutans biofilm was more susceptible to the TMP or HMP - AgNP nanocomposites than the C. albicans biofilm, with respective reductions of 2.88 - 3.71 log 10 and 0. 45 - 1.43 log 10 . The nanocomposites allowed a reduction of about 75% of the total biomass and about 90% of the metabolic activity in both biofilms. For the in vitro evaluation of the anticaries potential, a new nanocomposite containing 0.2% TMP, 100 ppm fluo rine and 10% Ag was synthesized and characterized by transmission electron microscopy (TEM). B ovine enamel blocks (4 mm x 4 mm, n = 60) selected by initial surface hardness (SHi) were allocated in five groups (n=12): deionized water (Placebo ), 100 ppm F (1 00 F), 225 ppm F (225 F), 100 ppm F + 0.2% TMP (100 F / TMP) and 100 ppm F + 0.2% TMP + 10% Ag (100F / TMP / Ag). The blocks were treated 2x daily with the solutions and subjected to five pH cycles (deismineralizang and remineralizing solutions) at 37 ° C. Then, the final surface hardness (SHf) and integrated subsurface hardness ( Δ KHN), the concentration of fluoride (F) and calcium (Ca) in the enamel was determined. The effectiveness of this nanocomposite (100F / TMP / Ag) against the formation of single an d mixed biofilms of C. albicans (ATCC 10231) and S . mutans (ATCC 25175) was evaluated by the count ing colony forming units (CFUs). Biofilms were also analyzed by scanning electron microscopy (SEM). Similar values of % SH wer e observed for groups 225F, 100F /TMP and 100F/TMP Ag (p> 0.001). The 225F, 100F/TMP and 100F/TMP/Ag solutions showed capacity to reduce the lesion body (ΔKHN) in the depth of 5 - 20 μm. F concentration was similar in the enamel for the 100F/TMP/Ag and 225F (p> 0.001). The groups 100F, 225F, 100F/TMP and 100F/TMP/Ag presented the highest and the same concentration of Ca (p> 0.001). In relation to viable cells 100F/TMP/Ag nanocomposite promoted significant log reductions in the number of CFUs of S. mutans , of 5.42 and 4.46 log 10 respectivel y in single and mixed biofilms and C. albicans was mor e resistant. SEM images confirmed these results. The surface hardness (% SH) was similar in the samples treated with solutions containing 225F, 100F/TMP and 100F/TMP/ Ag (p> 0.001). In addition, the abil ity to reduce the lesion body (ΔKHN) was greater in 110F, 225F, 100F / TMP and 100F/TMP/ Ag (p <0.001) in zone A (5 - 20 μm) and in zone B only with 225F and 100F/TMP. The 100F/TMP/ Ag group showed greater demineralization in zone B (20 - 130 μm) (p <0.001). The F concentration of the 100F /TMP/ Ag solution was similar to 225F (p <0. 001). Groups 100F, 225F, 100F/ TMP and 100F /TMP/ Ag showed the highest and the same concentration of Ca (p> 0.001).Although the 100F/TMP/Ag solution yielded lower values of lesion deep ar eas than the solution containing 225 ppm F, but the nanocomposite was able to inhibit demineralization of surface of enamel. These compounds have demonstrated significant antimicrobial activity, especially against S. mutans , and can be considered a potenti al alternative for new dental bio materials , aiming at the prevention or treatment of carious lesions .

Orientador: Juliano Pelim Pessan / Coorientador: Alberto Carlos Botazzo Delbem / Coorientador: Marcelle Danelon / Banca: Célio Percinoto / Banca: Cleide Cristina Rodrigues Martinhon / Banca: Douglas Roberto Monteiro / Banca: Heitor Marques Honório / Resumo: O presente estudo avaliou o efeito de vernizes fluoretados contendo nanopartículas de trimetafosfato de sódio (TMP) sobre a remineralização de lesões de cárie e erosão de esmalte dental in vitro. Assim como o padrão de liberação de F e TMP a partir destas formulações. Os vernizes testados foram: Placebo (sem flúor ou TMP, controle negativo), 2,5% NaF, 5% NaF (controle positivo), 5% NaF + 5% TMP microparticulado, 5% NaF + 2,5% TMP nanoparticulado, 5% NaF + 5% TMP nanoparticulado, além de uma formulação comercial (Duraphat), doravante denominados PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2,5%TMPnano, 5%F+5%TMPnano e Duraphat, respectivamente. Na 1ª fase, lesões de cárie artificiais foram induzidas em blocos de esmalte bovino (n=168), os quais foram selecionados por dureza de superfície (DS). Os blocos receberam uma aplicação dos vernizes supracitados, permanecendo em contato durante 6 h. Metade dos blocos (n=12/grupo) foi utilizada para determinação da concentração de CaF2 e FA formado após o tratamento com os vernizes. A outra metade foi submetida um modelo de ciclagem de pH (6 dias). Os blocos foram analisados quanto a porcentagem de recuperação de dureza de superfície (%RDS), dureza em secção longitudinal (ΔKHN), CaF2 e FA retidos após a ciclagem de pH. Os vernizes contendo TMP promoveram %RDS significativamente maior em comparação ao verniz contendo 5%F, sem diferenças significativas entre os vernizes com TMP. Um padrão semelhante foi observado para ΔKHN, embora os valores obtid... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study evaluated the effect of fluoride varnishes containing nano-sized sodium trimetaphosphate (TMP) on the remineralization of artificial caries lesions and erosion of dental enamel in vitro. As well as the pattern of F and TMP release from these formulations. The varnishes tested were: Placebo (without fluoride or TMP, negative control), 2.5% NaF, 5% NaF (positive control), 5% NaF + 5% TMP micrometric, 5% NaF + 2.5% nano-sized TMP, 5% NaF + 5% nano-sized TMP, besides a commercial formulation (Duraphat), hereafter referred to as PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2.5%TMPnano, 5%F+5%TMPnano and Duraphat, respectively. In the first phase, artificial caries lesions were induced on bovine enamel blocks (n=168), which were selected by surface hardness (SH). Blocks received a single application of the aforementioned varnishes, remaining in contact for 6 h. Half of the blocks (n=12/group) were used to determine the concentration of CaF2 and FA fluoride formed on the specimens after the treatment with the varnishes. The other half was subjected to a pH cycling model (6 days). The blocks were analyzed for the percentage of SH recovery (%SHR), cross-sectional hardness (ΔKHN), CaF2 and FA retained after pH cycling. The varnishes containing TMP promoted significantly higher %SHR compared to 5%F, without significant differences among the TMP-containing varnishes. A similar pattern was observed for ΔKHN, although the values obtained for 5%F+5%TMPnano were 25% lower than those obtained for 5%F+5%TMPmicro. The highest CaF2 concentrations were promoted by 5%F, 5%F+5%TMPmicro and Duraphat varnishes. The second phase evaluated the protective effect of PLA, 5%F, 5%F+5%TMPmicro, 5%F+2.5%TMPnano and 5%F+5%TMPnano varnishes on initial erosion of bovine enamel. Specimens (n=8), selected by SH, received a single application of the varnishes, remaining in contact for 6 h. Varnishes were... / Doutor

Orientador: Debora de Barros Barbosa / Coorientadora: Marcelle Danelon / Coorientadora: Jackeline Gallo do Amaral / Banca: Denise Pedrini Ostini / Banca: Alberto Carlos Botazzo Delbem / Banca: Emerson Rodrigues de Camargo / Banca: Renan Aparecido Fernandes / Resumo: O objetivo deste estudo foi sintetizar e caracterizar nanocompósitos formados por polifosfatos (trimetafosfato de sódio (TMP) ou hexametafosfato de sódio (HMP)) e flúor (F) associados à nanopartículas de prata. Esses nanocompósitos foram avaliados quanto à sua ação anti-biofilme de Candida albicans (ATCC 10231) e Streptococcus mutans (ATCC 25175) e seu potencial em inibir a desmineralização do esmalte dentário por meio de ensaio in vitro de ciclagem de pH. As nanopartículas de prata foram sintetizadas através da redução do nitrato de prata (1 ou 10%) pelo borihidreto de sódio (NaBH4) em meio isopropílico contendo trimetafosfato de sódio (TMP) ou hexametafosfato de sódio (HMP)) e flúor (F). Os nanocompósitos foram caracterizados por microscopia eletrônica de varredura (MEV) e por difração de raios-X, e também determinada a concentração inibitória mínima (MIC) contra células planctônicas de C. albicans e S. mutans. A efetividade contra biofilmes pré-formados de 24h dos nanocompósitos, foi testada em concentrações de 1x e 10x os valores de MIC (de 40μg Ag ml−1), avaliada através da quantificação de células cultiváveis (CFUs), da atividade metabólica (XTT) e da biomassa total (Cristal Violeta). Os nanocompósitos contendo 10% de Ag apresentaram maior efetividade antimicrobiana contra ambos os microrganismos, comparados aos nanocompósitos contendo 1% de prata. O biofilme de S. mutans foi mais suscetível aos nanocompósitos TMP ou HMP/AgNP que o biofilme de C. albicans, com reduções ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to synthesize and characterize nanocomposites formed polyphosphates (sodium trimetaphosphate (TMP) or sodium hexametaphosphate (HMP)) and fluoride (F) associated with silv er nanoparticles. The anti - biofilm activity of the nanocomposites were evaluated against Candida albicans (ATCC ATCC 10231) and Streptococcus mutans (ATCC 25175) . as well as their potential in inhibiting demineralization and increasing the remineralizatio n of dental enamel by in vitro pH cycling assay. Silver nanoparticles were synthesized by reduction of silver nitrate (1 or 10%) by sodium bor ohydride (NaBH 4 ) in isopropylic medium containing sodium trimetaphosphate (TMP) or sodium hexametap hosphate (HMP)) and fluoride (F) . The nanocomposites were characterized by scanning electron microscopy (SEM) and X - ray diffraction. The minimum inhibitory concentration (MIC) of the nanocomposites was determined against planktonic cells of C. albicans and S. mutans . Eff ect iveness of preformed 24 - hour biofilms of nanocomposites at 1x and 10x MIC values was assessed by quantifying viable cells (CFUs), metabolic activity (XTT) and total biomass (Crystal Violet). The nanocomposites containing 10% Ag showed higher antimicrobia l effectiveness against both microorganisms compared to nanocomposites containing 1% silver. The S. mutans biofilm was more susceptible to the TMP or HMP - AgNP nanocomposites than the C. albicans biofilm, with respective reductions of 2.88 - 3.71 log 10 and 0.... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-06-11T19:23:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-26Bitstream added on 2014-06-13T18:09:32Z : No. of bitstreams: 1 iocca_af_me_arafcf.pdf: 839645 bytes, checksum: fe164c1377bc1c5f8fee7c3e6cc68fa6 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi avaliar a adição de várias formas de apresentação de plasma bovino (líquido e desidratado) a salmouras isentas de polifosfato na estabilidade física, química, microbiológica e sensorial de bifes de coxão duro (m.Biceps femoris) injetado, cru e cozido, mantido sob refrigeração (2°C e 7°C), divididos em 2 ensaios, respectivamente. Os cortes foram obtidos de um mesmo lote de abate, oriundos de bovinos Bos indicus machos. No 1º ensaio, utilizou-se 30 cortes de coxão duro, foram coletadas, periodicamente, amostras para as análises microbiológicas, físicas, químicas e sensoriais dos diferentes tratamentos, objetivando o estudo da vida útil destes cortes em função dos tipos de ingredientes injetados. Em seguida, no segundo ensaio com 21 cortes de coxão duro, foi analisado o efeito do lactato e do diacetato de sódio, aplicados isoladamente e/ou combinados, introduzidos à salmoura juntamente com o plasma para a avaliação da vida útil dos bifes marinados e cozidos; seguindo a mesma metodologia de análise do primeiro ensaio. As várias formas de apresentação do plasma bovino, sob o aspecto de rendimento e qualidade sensorial podem ser utilizadas na injeção de cortes bovinos cozidos, porém é necessário que seja realizado uma coleta mais higiênica do sangue bovino devido à alta carga microbiana. Contudo, sob o aspecto microbiológico, apenas o plasma bovino desidratado pode ser utilizado em cortes marinados destinados à comercialização crua e cozida combinado com Optiform® (lactato de sódio + diacetato de sódio). No primeiro ensaio, obteve-se uma qualidade microbiológica aceitável até o 35°dia de estocagem (2°C) da carne cozida, entretanto no segundo ensaio com temperatura de armazenagem de 7°C este prazo diminuiu para 14 dias, comprovando que a temperatura tem fator importante no crescimento dos microrganismos deterioradores... / The objective of this study assayed the addition of various presentation ways of bovine plasma (liquid and dehydrated) to brines free of polyphosphate on physical, chemical, microbiological and sensorial stability of injected, raw and cooked outside round beefs, kept under refrigeration (2ºC and 7ºC), shared in 2 steps, respectively. The cuts were obtained from the same slaughter group, natural of male Bos indicus bovines. In the first step, using 30 outside round cuts, were collected samples periodically to the microbiological, physical, chemical and sensorial analysis of different treatments, objectifying the shelf-life study from these cuts in function of kinds of injected ingredients. Later, in the second step with 21 outside round cuts, were analyzed the lactate and sodium diacetate effects, applied lonely and/or combined, introduced to the brine with the plasma to evaluate the shelf-life of enhanced and cooked beefs; following the same analysis methodology from the first step. The various presentation ways of bovine plasma, under the aspect of yield and sensorial quality can be used in the injection of cooked bovine cuts, but it is necessary to be done a more hygienic collect of bovine blood due to the high microbiological counting. Nevertheless, under the microbiological aspect, only the dehydrated bovine plasma can be used in enhanced cuts destined for trade in raw and cooked way combined with Optiform® (sodium lactate + sodium diacetate). In the first step, was obtained an acceptable microbiological quality until the 35º day of storage (2ºC) of cooked meat, however in the second step with storage temperature of 7ºC this time decreased to 14 days, proving that the temperature is an important factor on growing of acid-fermentative spoiler microorganisms

Le fromage fondu est un produit alimentaire de seconde transformation obtenu après mélange et cuisson de fromages, additionnés éventuellement d'autres ingrédients laitiers. Ce produit, dont la consommation croit dans de nombreuses régions du monde, présente une grande variété d'applications et peut être conservé plusieurs mois à température ambiante. Cependant, les mécanismes moléculaires sous-jacents à sa structuration biochimique demeurent mal connus et sa fabrication industrielle reste souvent empirique.L'objectif général de ce travail est d'améliorer la compréhension des étapes de structuration biochimique du fromage fondu de type « portion triangulaire tartinable », au cours des étapes de sa fabrication. Dans un premier temps, les propriétés physico-chimiques des sels de fonte, additifs ajoutés au fromage fondu, ont été étudiées dans des milieux modèles de complexités croissantes, de la solution aqueuse jusqu'au lait écrémé. La composition de ces sels de fonte, leur hydrolyse après traitement thermique ainsi que leur interaction avec certains constituants laitiers ont été évaluées par deux méthodes complémentaires : la chromatographie ionique et la RMN du phosphore. Par ailleurs, il a été montré que ces sels, via la chélation du calcium, induisaient la dissociation des caséines, modifiant les propriétés d'hydratation et d'émulsification de ces dernières.Dans un deuxième temps, le rôle des sels de fonte quant à la structuration des protéines, de l'eau, des minéraux et de la matière grasse a été analysé dans des matrices plus complexes : les portions triangulaires tartinables, aux étapes clés de leur fabrication. Un mécanisme d'interaction des constituants biochimiques majoritaires a été proposé, prenant en compte l'évolution des molécules sous l'effet des contraintes physiques et chimiques appliquées au cours du procédé. / Processed cheese is manufactured by the secondary processing food industry, by mixing and heating cheese, along with other dairy ingredients. This product, whose consumption grows in many parts of the world, has a wide variety of applications and can be stored for several months at room temperature. However, the molecular mechanisms underlying its structure remain poorly understood and industrial production is often empirical. The general objective of this work is to improve the understanding of biochemical steps structuring spreadable processed cheese during its manufacture. At first, the physico-chemical properties of additives used in processed cheese, i.e. emulsifying salts, have been studied in simplified environments of increasing complexity, from aqueous solutions to skimmed milk. The composition of theses salts, their hydrolysis after heat treatment and their interaction with some dairy constituents were assessed by two complementary methods: ion chromatography and phosphorus NMR. Moreover, it has been shown that these salts, through the calcium chelation, induced casein dissociation and modified their hydration and emulsifying properties. Then, the role of these salts on the structure and interactions between proteins, water, minerals and fat were analyzed in spreadable processed cheese, at different steps of its manufacture. A mechanism of interaction between the major biochemical constituents has been proposed, taking into account the evolution of molecules under the influence of physical and chemical constraints applied during the process.

La maladie d'Alzheimer est la démence la plus répandue dans le monde. Le nombre de cas augmente de manière exponentielle et il est donc important de comprendre les mécanismes moléculaires donnant lieu à cette terrible maladie. Une des hypothèses les plus supportées est celle suggérant que la production et dégradation déséquilibrées de l'amyloïde-beta (Aß), un peptide de 42 acides aminés trouvé dans tous les individus sains, est un événement clé dans le déroulement de la maladie d'Alzheimer. En effet, une production accrue ou une dégradation faible du peptide ont pour conséquence son agrégation et accumulation dans des plaques de fibres entre les neurones des régions spécifiques du cerveau. C'est pourquoi la modulation de l'agrégation du peptide Aß est une des approches envisageables pour modifier l'évolution de la maladie d'Alzheimer. Les protéines chaperons dont une des fonctions est d'assister d'autres protéines dans leur repliement, sont parmi les molécules les plus étudiées pour leur capacité modulatrice de l'agrégation des protéines (inclus le peptide Aß). Plusieurs chaperons ont montré la capacité d'inhiber la formation des fibres par l'Aß. Cependant, du fait que les chaperons sont des molécules conservées et peu spécifiques, leur surexpression ou administration directe peut avoir des conséquences négatives si les chaperons interagissent avec des protéines autres que la protéine cible. Dans ce travail, nous nous sommes intéressés à une protéine chaperon bactérienne possédant une forte activité " holdase " (i.e., elle empêche le repliement précoce des protéines) comme possible modulateur de l'agrégation du peptide Aß. Le chaperon sauvage a une très faible capacité d'inhibition de la formation de fibres par le peptide Aß. Cependant, nous avons démontré qu'en modifiant légèrement la surface de liaison du chaperon, la protéine devient un puissant inhibiteur de l'agrégation d'Aß. En parallèle, nous nous sommes intéressés à l'influence des ions métalliques sur l'agrégation du peptide Aß. [...] / Alzheimer's disease is the most frequent type of dementia. With an exponentially growing number of cases, understanding the underlying molecular events leading to this devastating condition is of crucial importance. Much evidence points to a disequilibrium in the production and degradation of amyloid beta (Aß), a normally physiological 42 amino acid peptide, as an early key event in Alzheimer's etiology. Whether Aß is overproduced or poorly degraded, the overall result is an abnormally large pool of peptide that gradually aggregates forming extracellular deposits of fibrils, called amyloid plaques, in specific brain regions. Hence, modulation of Aß aggregation process is one of the suggested approaches to control the evolution of Alzheimer's disease. Universally conserved molecular chaperones have been intensively studied for their capacity to prevent aggregation of disease-related proteins, and many of them have proven to efficiently modulate Alzheimer's Aß aggregation. In a scenario where chaperones are overexpressed or directly administered into the affected tissue, the universal conservation and the relatively poor client-specificity of generic chaperones can become a downside because of the risk of interaction with proteins other than the targeted one is not dismissible, and thus the consequences unpredictable. In the first part of this work, we looked upon a bacterial chaperone call SecB with an unusually robust holdase activity (i.e. it prevents early protein folding) as a promising modulator of Alzheimer's Aß peptide aggregation. [...]

Phosphorus (P) is a requirement for biological growth, but this vital nutrient is present at low or limiting concentrations across vast areas of the global surface ocean. Inorganic polyphosphate (poly-P), a linear polymer of at least three orthophosphate units, is one component of the marine P cycle that has been relatively overlooked as compared to other P species, owing in part to a lack of routine analytical techniques that cleanly evaluate it within samples. This thesis demonstrates that inorganic poly-P is a quantitatively significant and dynamic component of the global marine P cycle while also establishing two new techniques for its analysis in biological and environmental samples. In Chapter 2, experiments using the freshwater algae Chlamydomonas sp. and Chlorella sp. illustrate X-ray fluorescence spectromicroscopy as a powerful tool for the sub-micron scale assessment of poly-P composition in organisms. This method enabled the discovery, detailed in Chapter 3, of a mechanism for the long-term sequestration of the vital nutrient P from marine systems via the initial formation of poly-P in surface waters and its eventual transformation into the mineral apatite within sediments. The importance of marine poly-P is furthermore established in Chapter 3 by observations showing that naturally-occurring poly-P represents 7-11% of total P in particles and dissolved matter in Effingham Inlet, a eutrophic fjord located on Vancouver Island, British Columbia. In Chapter 4, a new fluorometric protocol based on the interaction of inorganic poly-P with 4',6-diamidino-2-phenylindole (DAPI) is established as a technique for the direct quantification of poly-P in environmental samples. Chapter 5 presents work from Effingham Inlet utilizing this method that show that inorganic poly-P plays a significant role in the redox-sensitive cycling of P in natural systems.

Resumo: O objetivo deste estudo foi avaliar a adição de várias formas de apresentação de plasma bovino (líquido e desidratado) a salmouras isentas de polifosfato na estabilidade física, química, microbiológica e sensorial de bifes de coxão duro (m.Biceps femoris) injetado, cru e cozido, mantido sob refrigeração (2°C e 7°C), divididos em 2 ensaios, respectivamente. Os cortes foram obtidos de um mesmo lote de abate, oriundos de bovinos Bos indicus machos. No 1º ensaio, utilizou-se 30 cortes de coxão duro, foram coletadas, periodicamente, amostras para as análises microbiológicas, físicas, químicas e sensoriais dos diferentes tratamentos, objetivando o estudo da vida útil destes cortes em função dos tipos de ingredientes injetados. Em seguida, no segundo ensaio com 21 cortes de coxão duro, foi analisado o efeito do lactato e do diacetato de sódio, aplicados isoladamente e/ou combinados, introduzidos à salmoura juntamente com o plasma para a avaliação da vida útil dos bifes marinados e cozidos; seguindo a mesma metodologia de análise do primeiro ensaio. As várias formas de apresentação do plasma bovino, sob o aspecto de rendimento e qualidade sensorial podem ser utilizadas na injeção de cortes bovinos cozidos, porém é necessário que seja realizado uma coleta mais higiênica do sangue bovino devido à alta carga microbiana. Contudo, sob o aspecto microbiológico, apenas o plasma bovino desidratado pode ser utilizado em cortes marinados destinados à comercialização crua e cozida combinado com Optiform® (lactato de sódio + diacetato de sódio). No primeiro ensaio, obteve-se uma qualidade microbiológica aceitável até o 35°dia de estocagem (2°C) da carne cozida, entretanto no segundo ensaio com temperatura de armazenagem de 7°C este prazo diminuiu para 14 dias, comprovando que a temperatura tem fator importante no crescimento dos microrganismos deterioradores ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study assayed the addition of various presentation ways of bovine plasma (liquid and dehydrated) to brines free of polyphosphate on physical, chemical, microbiological and sensorial stability of injected, raw and cooked outside round beefs, kept under refrigeration (2ºC and 7ºC), shared in 2 steps, respectively. The cuts were obtained from the same slaughter group, natural of male Bos indicus bovines. In the first step, using 30 outside round cuts, were collected samples periodically to the microbiological, physical, chemical and sensorial analysis of different treatments, objectifying the shelf-life study from these cuts in function of kinds of injected ingredients. Later, in the second step with 21 outside round cuts, were analyzed the lactate and sodium diacetate effects, applied lonely and/or combined, introduced to the brine with the plasma to evaluate the shelf-life of enhanced and cooked beefs; following the same analysis methodology from the first step. The various presentation ways of bovine plasma, under the aspect of yield and sensorial quality can be used in the injection of cooked bovine cuts, but it is necessary to be done a more hygienic collect of bovine blood due to the high microbiological counting. Nevertheless, under the microbiological aspect, only the dehydrated bovine plasma can be used in enhanced cuts destined for trade in raw and cooked way combined with Optiform® (sodium lactate + sodium diacetate). In the first step, was obtained an acceptable microbiological quality until the 35º day of storage (2ºC) of cooked meat, however in the second step with storage temperature of 7ºC this time decreased to 14 days, proving that the temperature is an important factor on growing of acid-fermentative spoiler microorganisms / Orientador: Maria da Penha Longo Mortatti Catanozi / Coorientador: Ana Lúcia da Silva Correa Lemos / Banca: Luciana Miyagusku / Banca: Pedro Fernando Romanelli / Mestre

Submitted by LILIANA CAROLINA BAEZ QUINTERO null (lilianacarolina@gmail.com) on 2018-01-22T02:00:15Z No. of bitstreams: 1 Tese Liliana Báez 19-01-17.pdf: 2043746 bytes, checksum: 4dd42f1670ab6d50fd3058c4a341fe83 (MD5) / Approved for entry into archive by Ana Paula Rimoli de Oliveira null (anapaula@foa.unesp.br) on 2018-01-22T11:43:59Z (GMT) No. of bitstreams: 1 baez-quintero_ml_dr_araca_int.pdf: 1967299 bytes, checksum: 23b7a06e3edce27a7c9198383d5f4458 (MD5) / Made available in DSpace on 2018-01-22T11:43:59Z (GMT). No. of bitstreams: 1 baez-quintero_ml_dr_araca_int.pdf: 1967299 bytes, checksum: 23b7a06e3edce27a7c9198383d5f4458 (MD5) Previous issue date: 2017-12-20 / O presente estudo avaliou o efeito de vernizes fluoretados contendo nanopartículas de trimetafosfato de sódio (TMP) sobre a remineralização de lesões de cárie e erosão de esmalte dental in vitro. Assim como o padrão de liberação de F e TMP a partir destas formulações. Os vernizes testados foram: Placebo (sem flúor ou TMP, controle negativo), 2,5% NaF, 5% NaF (controle positivo), 5% NaF + 5% TMP microparticulado, 5% NaF + 2,5% TMP nanoparticulado, 5% NaF + 5% TMP nanoparticulado, além de uma formulação comercial (Duraphat), doravante denominados PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2,5%TMPnano, 5%F+5%TMPnano e Duraphat, respectivamente. Na 1ª fase, lesões de cárie artificiais foram induzidas em blocos de esmalte bovino (n=168), os quais foram selecionados por dureza de superfície (DS). Os blocos receberam uma aplicação dos vernizes supracitados, permanecendo em contato durante 6 h. Metade dos blocos (n=12/grupo) foi utilizada para determinação da concentração de CaF2 e FA formado após o tratamento com os vernizes. A outra metade foi submetida um modelo de ciclagem de pH (6 dias). Os blocos foram analisados quanto a porcentagem de recuperação de dureza de superfície (%RDS), dureza em secção longitudinal (ΔKHN), CaF2 e FA retidos após a ciclagem de pH. Os vernizes contendo TMP promoveram %RDS significativamente maior em comparação ao verniz contendo 5%F, sem diferenças significativas entre os vernizes com TMP. Um padrão semelhante foi observado para ΔKHN, embora os valores obtidos para 5%F+5%TMPnano tenham sido 25% menores que os obtidos para 5%F+5%TMPmicro. As maiores concentrações de CaF2 foram promovidas pelos vernizes 5%F, 5%F+5%TMPmicro e Duraphat. A 2ª fase avaliou o efeito protetor dos vernizes PLA, 5%F, 5%F+5%TMPmicro, 5%F+2,5%TMPnano e 5%F+5%TMPnano sobre a erosão de esmalte bovino. Os espécimes (n=8), selecionados por DS, receberam uma única aplicação dos vernizes, permanecendo em contato durante 6 h. Em seguida, os vernizes foram removidos e os blocos, submetidos a quatro desafios erosivos individuais (1 minuto, ácido cítrico, 0,75%, pH = 3,5, sob agitação), sendo analisados por DS após cada desafio. Em geral, observou-se a maior porcentagem de alteração de DS para PLA, seguido de 5%F, 5%F+5%TMPmicro e ambos os vernizes contendo TMPnano, sem diferenças significativas entre 5%F+2,5%TMPnano e 5%F+5%TMPnano. Por fim, a 3ª fase avaliou o padrão de liberação de flúor e fosfato dos vernizes PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2,5%TMPnano, 5%F+5%TMPnano e Duraphat ao longo de 24 h, em um modelo de ciclagem de pH. Os vernizes foram aplicados em tiras de poliéster (n=8/grupo), as quais foram alternadamente imersas em soluções remineralizadora e desmineralizadora aos 30, 60, 90, 120, 180, 240, 300, 360, 420, 540, 600, 720, 780, 960, 1200 e 1440 min após a primeira imersão. As soluções foram analisadas quanto às concentrações de flúor e fosfato. Os vernizes contendo TMP apresentaram um padrão crescente exponencial quanto a liberação cumulativa de flúor até 6 horas, atingindo um platô nos tempos seguintes. Em acréscimo, os vernizes liberaram maiores quantidades de flúor quando imersos em solução desmineralizadora. De forma geral, os vernizes contendo TMPnano liberaram quantidades significativamente maiores de flúor em comparação ao TMPmicro. Os resultados da 1ª fase permitem concluir que a adição de TMP a vernizes fluoretados aumenta significativamente seu potencial remineralizador em lesões de cárie artificiais, com um efeito adicional com o uso de TMPnano em relação ao TMPmicro, embora este acréscimo não seja estatisticamente significativo. Quanto ao efeito contra desafios erosivos (2ª fase), um padrão semelhante foi observado, tendo o maior efeito protetor sido observado para os vernizes contendo TMPnano, o qual foi significativamente maior que os demais grupos. O maior efeito dos vernizes suplementados com TMP parece estar relacionado à maior liberação de flúor destes (3ª fase), especialmente TMPmicro, associada à liberação constante de TMP a partir destas formulações. / The present study evaluated the effect of fluoride varnishes containing nano-sized sodium trimetaphosphate (TMP) on the remineralization of artificial caries lesions and erosion of dental enamel in vitro. As well as the pattern of F and TMP release from these formulations. The varnishes tested were: Placebo (without fluoride or TMP, negative control), 2.5% NaF, 5% NaF (positive control), 5% NaF + 5% TMP micrometric, 5% NaF + 2.5% nano-sized TMP, 5% NaF + 5% nano-sized TMP, besides a commercial formulation (Duraphat), hereafter referred to as PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2.5%TMPnano, 5%F+5%TMPnano and Duraphat, respectively. In the first phase, artificial caries lesions were induced on bovine enamel blocks (n=168), which were selected by surface hardness (SH). Blocks received a single application of the aforementioned varnishes, remaining in contact for 6 h. Half of the blocks (n=12/group) were used to determine the concentration of CaF2 and FA fluoride formed on the specimens after the treatment with the varnishes. The other half was subjected to a pH cycling model (6 days). The blocks were analyzed for the percentage of SH recovery (%SHR), cross-sectional hardness (ΔKHN), CaF2 and FA retained after pH cycling. The varnishes containing TMP promoted significantly higher %SHR compared to 5%F, without significant differences among the TMP-containing varnishes. A similar pattern was observed for ΔKHN, although the values obtained for 5%F+5%TMPnano were 25% lower than those obtained for 5%F+5%TMPmicro. The highest CaF2 concentrations were promoted by 5%F, 5%F+5%TMPmicro and Duraphat varnishes. The second phase evaluated the protective effect of PLA, 5%F, 5%F+5%TMPmicro, 5%F+2.5%TMPnano and 5%F+5%TMPnano varnishes on initial erosion of bovine enamel. Specimens (n=8), selected by SH, received a single application of the varnishes, remaining in contact for 6 h. Varnishes were then removed and the blocks, submitted to four individual erosive challenges (1 minute, citric acid, 0.75%, pH = 3.5, under stirring) and analyzed by SH after each challenge. Overall, the highest percentage of SH change was observed for PLA, followed by 5%F, 5%F+5%TMPmicro and both varnishes containing TMPnano, with no significant differences between 5%F+2.5%TMPnano, 5%F+5%TMPnano. Finally, the third phase evaluated the pattern of fluoride and phosphate release from PLA, 2.5%F, 5%F, 5%F+5%TMPmicro, 5%F+2.5%TMPnano, 5%F+5%TMPnano and Duraphat varnishes over 24 h, in a pH cycling model. The varnishes were applied on polyester sheets (n=8/group), which were alternately immersed in remineralizing and demineralizing solutions at 30, 60, 90, 120, 180, 240, 300, 360, 420, 540, 600, 720 , 780, 960, 1200 and 1440 min after the first immersion. The solutions were analyzed for fluoride and phosphate concentrations. The varnishes containing TMP promoted an increasing, exponential pattern for the cumulative fluoride release up to 6 hours, reaching a plateau afterwards. In addition, higher quantities of fluoride were released when varnishes were immersed in the demineralizing solution. In general, varnishes containing TMPnano released significantly higher amount of fluoride compared to TMPmicro. The results of the 1st phase allow to conclude that the addition of TMP to fluoride varnishes significantly increases its remineralizing potential in artificial caries lesions, with an additional effect with the use of TMPnano in relation to TMPmicro, this increment was not statistically significant. As for the effect against erosive challenges (2nd phase), a similar pattern was observed, with the highest protective effect observed for both varnishes containing TMPnano, which was significantly higher than the other groups. The higher effect of varnishes supplemented with TMP seems to be related to the higher fluoride release from these products (3rd phase), especially TMPmicro, associated to the constant release of TMP from these formulations.