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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Radiolabelled Oligonucleotides for Evaluation of in vivo Hybridisation Utilising PET Methodology

Lendvai, Gábor January 2007 (has links)
<p>Antisense oligonucleotides (ODN) may interfere in gene expression on the basis of hybridising to its complementary messenger RNA (mRNA) sequence in the cell thereby preventing the synthesis of the peptide. Therefore, these ODNs may be potential drugs to treat human diseases by “knocking down” the expression of responsible genes or correcting the maturation process of mRNA in the field called antisense therapy. Moreover, antisense ODNs upon labelling are also potential imaging agents to monitor gene expression <i>in vivo</i>, i.e. to accomplish <i>in vivo</i> hybridisation. This would provide a non-invasive tool compared to present methods, which require tissue samples. </p><p>This goal may be reached using positron emission tomography (PET) methodology. PET is a most advanced <i>in vivo</i> imaging technology, which would allow exploring the fate of radionuclide-labelled antisense ODNs in the body; thereby providing information about biodistribution and quantitative accumulation in tissues to assess pharmacokinetic properties of ODNs. This kind of evaluation is important as part of the characterisation of antisense therapeutics but also as part of the development of antisense imaging agents.</p><p>The present study aimed to investigate <sup>76</sup>Br- and <sup>68</sup>Ga-labelled ODNs of five different modifications: phosphodiester, phosphorothioate, 2'-<i>O</i>-methyl phosphodiester, locked nucleic acid (LNA), and peptide nucleic acid. The study included exploration of the hybridisation abilities of these ODNs after labelling; furthermore, the biodistribution, metabolite analysis and uptake of the ODNs in rats regarding non-hybridisation and hybridisation specific uptake was conducted. Among the ODNs studied, LNA-DNA mixmer (LNA and DNA nucleotides in alternation along the sequence) displayed the most promising characteristics considering a higher retention in tissues, stability and longer plasma residence. However, biodistribution data demonstrated a non-hybridisation specific distribution in rat tissues with kidney, liver, spleen and bone marrow being the organs of high uptake. Scavenger receptors or other saturable processes unrelated to hybridisation may play a role in tissue uptake and in clearance of antisense ODNs through these organs. These processes may be sequence dependent suggesting that proof of <i>in vivo</i> hybridisation through imaging needs much more elaborate evaluations than just comparison of sense and antisense sequences and proving dose-dependency.</p>
362

Radiolabelled Oligonucleotides for Evaluation of in vivo Hybridisation Utilising PET Methodology

Lendvai, Gábor January 2007 (has links)
Antisense oligonucleotides (ODN) may interfere in gene expression on the basis of hybridising to its complementary messenger RNA (mRNA) sequence in the cell thereby preventing the synthesis of the peptide. Therefore, these ODNs may be potential drugs to treat human diseases by “knocking down” the expression of responsible genes or correcting the maturation process of mRNA in the field called antisense therapy. Moreover, antisense ODNs upon labelling are also potential imaging agents to monitor gene expression in vivo, i.e. to accomplish in vivo hybridisation. This would provide a non-invasive tool compared to present methods, which require tissue samples. This goal may be reached using positron emission tomography (PET) methodology. PET is a most advanced in vivo imaging technology, which would allow exploring the fate of radionuclide-labelled antisense ODNs in the body; thereby providing information about biodistribution and quantitative accumulation in tissues to assess pharmacokinetic properties of ODNs. This kind of evaluation is important as part of the characterisation of antisense therapeutics but also as part of the development of antisense imaging agents. The present study aimed to investigate 76Br- and 68Ga-labelled ODNs of five different modifications: phosphodiester, phosphorothioate, 2'-O-methyl phosphodiester, locked nucleic acid (LNA), and peptide nucleic acid. The study included exploration of the hybridisation abilities of these ODNs after labelling; furthermore, the biodistribution, metabolite analysis and uptake of the ODNs in rats regarding non-hybridisation and hybridisation specific uptake was conducted. Among the ODNs studied, LNA-DNA mixmer (LNA and DNA nucleotides in alternation along the sequence) displayed the most promising characteristics considering a higher retention in tissues, stability and longer plasma residence. However, biodistribution data demonstrated a non-hybridisation specific distribution in rat tissues with kidney, liver, spleen and bone marrow being the organs of high uptake. Scavenger receptors or other saturable processes unrelated to hybridisation may play a role in tissue uptake and in clearance of antisense ODNs through these organs. These processes may be sequence dependent suggesting that proof of in vivo hybridisation through imaging needs much more elaborate evaluations than just comparison of sense and antisense sequences and proving dose-dependency.
363

Understanding factors influencing starch degradation dynamics in monogastrics: in vitro and in vivo approaches

GIUBERTI, GIANLUCA 23 February 2012 (has links)
Lo scopo del presente lavoro è stato quello di esaminare il potenziale di idrolisi e degradabilità dell’amido dei cereali e co-prodotti e di valutare gli aspetti collegati. L’approccio utilizzato comprende sia test in vitro che in vivo. In particolare: - Una serie d’indagini in vitro ha fornito dati sul potenziale di degradabilità enzimatica dell’amido dei cereali e co-prodotti considerando sia l’influenza della struttura dell’amido, del tipo di cereale, del rapporto amilosio:amilopectina, del processo termico, dell’insilamento, dello stadio di maturazione e delle pratiche agronomiche. - Una valutazione funzionale basata sul calcolo del potenziale di degradabilità enzimatica dell’amido tramite la stima dell’indice glicemico in vitro, combinata con un approccio matematico di modellizzazione dei dati ottenuti, è stata proposta per fornire un metodo efficace di screening dei materiali amidacei utilizzati comunamente nella formulazione per diete destinate ai suini. - Un esperimento in vitro è stato condotto per investigare la risposta glicemica post-prandiale in suini alimentati con diete che differivano nel potenziale di idrolisi enzimatica. Infine, considerando la crescente attenzione dei nutrizionisti sulla matrice proteica dei cereali (con particolare importanza data alle prolammine), i metodi comunemente utilizzati per le tecniche di estrazione delle prolammine sono stati confrontati e ri-investigati. / In the present work, it has been attempted to examine the variability in starch hydrolysis and digestion from cereal grains and co-products and to study aspects related, in order to give a better understand of the science behind the differences in grains/feeds starch digestion potential. The general approach was to use a combination of in vitro and in vivo techniques. In particular: - A series of in vitro investigations has provided data on the degradation potential of starch from cereal grains and co-products considering the influence of starch structure, cereal type, amylose-amylopectin ratio, heat processing, ensiling, stage of maturity and of agricultural practices. - A laboratory-based functional evaluation of starch value of cereal grains based on a predicted glycemic index approach, combined with a mathematical first-order exponential model, has been proposed in order to allow an efficient screening of starchy-materials entering in the pig diet formulation. - An in vivo experiment has been undertaken to investigate the postprandial plasma glucose response in pigs fed diets containing starch with a wide range in in vitro digestion patterns. Lastly, taking into account the increasing attention of swine nutritionists on prolamin proteins, the most commonly used prolamin extraction procedures were compared and reinvestigated, in order to get useful information for routine lab analysis.
364

Desenvolvimento e avaliação de um método in vitro para estimar a degradabilidade das proteínas no rúmen / Development and evaluation of an in vitro method to estimate the degradation of proteins in the rumen

Härter, Carla Joice 13 February 2009 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / A set of assays was carried out to develop a method for estimating ruminal degradation of proteins based on ammonia production in vitro. Samples of soybean meal, meat and bone meal, ryegrass (Lolium multiflorum) and cynodon (Cynodon dactilon var. Dactylon) were incubated by using the procedures of the in vitro/gas method. The effects of sample amount; starch inclusion to correct for ammonia uptaked by bacteria; nitrogen concentration in buffer solution and preview treatment of samples for soluble nitrogen extraction were evaluated. Short-time in vitro assays were also carried out to estimate degradation rate or solubilization rate of soluble fraction of nitrogen. Results of protein degradation obtained for some samples incubated in vitro were compared to those obtained from in situ and in vivo assays carried out in parallel. Results of protein degradation of different samples were not affected by sample size (15 mg N/ sample 1 g of sample) whereas degradability and dagradation rate of ryegrass protein, without starch correction, was negativelly affected by exclusion of ammonium bicarbonate from buffer solution (P<0,05). The preview extraction of soluble fraction of samples affected (P<0.05) protein degradation only of the ryegrass and soybean meal samples. Estimates of protein degradation for concentrate samples were not affected by starch inclusion. However, starch inclusion increased (P<0.05) protein degradation for ryegrass samples. Determination coefficient (r²) of regressions relating ammonia concentration and incubation time were usually high (above 0.80). Protein degradability of soybean meal, meat and bone meal and ryegrass samples were lower by in vitro than by in situ method (P<0.05). In turn, protein degradability of ryegrass and cynodon samples estimated in vitro was similar to obtained in vivo. In conclusion, although it needs more consistent validation, the in vitro/gas method might be an useful tool for estimating rumen degradabilty of proteins. / Foi conduzido um conjunto de ensaios in vitro com o objetivo de desenvolver um método para estimar a degradação de proteína no rúmen baseado na liberação de amônia no meio de incubação. Foram incubadas amostras de farelo de soja, farinha de carne e ossos, azevém (Lolium multiflorum) e cynodon (Cynodon dactilon var. Dactylon) utilizando-se os procedimentos da técnica in vitro/gases. Foi avaliado o efeito da quantidade de amostra incubada, da inclusão de amido para corrigir a fração de nitrogênio capturado pelas bactérias, do teor de nitrogênio na solução tampão e do tratamento prévio das amostras para remoção da fração solúvel do nitrogênio. Foram conduzidos também ensaios in vitro de curta duração para medir a taxa de degradação ou de solubilização da fração solúvel da proteína das amostras. Os resultados de degradação protéica obtidos em algumas amostras incubadas in vitro foram comparados com os obtidos em ensaios in vivo e in sito, que foram conduzidos paralelamente. A degradação da proteína de diferentes amostras não foi afetada pelo tamanho de amostra (15 mg N/ amostra 1 g de amostra), entretanto a degradabilidade e a taxa de degradação protéica do azevém, sem correção de amido, foram negativamente afetadas pela exclusão do bicarbonato de amônio da solução tampão (P<0,05). O tratamento prévio da amostra interferiu (P<0,05) nos resultados de degradação protéica das amostras de azevém e farelo de soja, mas não da farinha de carne. Em geral, a inclusão de amido para correção da amônia utilizada pelos microorganismos, resultou em maiores valores de degradabilidade da proteína do azevém (P<0,05), mas não das outras amostras. O coeficiente de determinação (r²) das estimativas da taxa de degradação, calculada com base na variação da concentração de amônia no meio ao longo do tempo de incubação, foram geralmente altos (superiores a 80%). As degradabilidades efetivas da proteína das amostras de farelo de soja, farinha de carne e azevém, estimadas pelo método in vitro foram inferiores às estimadas pelo método in situ (P<0,05). Por outro lado, a degradabilidade efetiva da proteína de amostras de azevém e Cynodon estimada pelo método in vitro não diferiu dos valores obtidos in vivo com ovinos fistulados no duodeno. Em conclusão, o método in vitro/gases pode ser uma ferramenta útil para estimar a degradabilidade ruminal das proteínas, embora ainda necessite ser melhor validado com estudos in vivo.
365

Intégration de la mesure d'impédance dans un système de stimulation électrique implantable multi-applications : proposition d'une nouvelle stratégie de stimulation / Impedance measurement integration into a multi-application implantable electrical stimulation system : proposition of an innovative stimulation strategy

Dupont, Florent 19 June 2014 (has links)
Cette thèse traite de l’architecture d’un stimulateur électrique multi applications implantable intégrant la mesure d’impédance du système électrode/tissu. Une large part du travail a concerné l’optimisation de la forme des stimuli générés par le circuit pour minimiser la consommation énergétique, garantir la forme d’onde des stimuli vue par les tissus et améliorer les analyses d’expériences fonctionnelles. En effet, l’interfaçage du stimulateur et des électrodes avec le milieu in vivo génère des contraintes sur la délivrance des stimuli électriques. Les stimuli délivrés par le générateur s’ils sont non adaptés à l’impédance du système électrode milieu environnant sont déformés par filtrage ou saturation.Une modélisation numérique du système électrode-milieu environnant a permis de mettre en évidence que ces différentes contraintes sont adressables si l’on utilise les informations données par la spectroscopie d’impédance. Une méthode basée sur une mesure d’impédance,suivie d’une identification sur un circuit électrique équivalent a été proposée ; elle permet d’estimer les contributions de l’interface électrode/milieu et du milieu. Ces fonctions de transfert sont ensuite utilisées pour la génération des stimuli électriques afin de garantir la forme d’onde définie par l’expérimentateur, au niveau des cibles de la stimulation. La preuve de concept de cette méthode a été faite en trois étapes : avec des composants électroniques équivalents, en milieu salin, puis en milieu in-vivo allant jusqu’à des tests fonctionnels permettant de démontrer l’intérêt d’une telle méthode.Ce travail s’est terminé par la proposition, la spécification haut-niveau et la simulation d’une architecture intégrée multi-applications innovante, basée sur le traitement des données d’impédance afin d’adapter la stimulation. / This thesis involves the research, design, developement and assessment of a novelelectrostimulation device capable of taking into account, and compensate for, the distorsion ofthe therapeutic signal due to the presence of the electrode-electrolyte interface, thus ensuringthat the desired signal waveform is in fact transmitted to the targeted tissues. This should resultin more effective and energy-efficient stimulation and also enable fundamental research on theeffects of signal waveforms on excitable tissue stimulation.The modelling of the electrode-tissu system enabled the demonstration that the electricalstimuli distorsion, due to frequential filtering or stimulator saturation, can be avoided by usingdatas extracted from a prior impedance spectroscopy. An equivalent electrical circuit is used tofit those data enabling the separation of electrode-electrolyte interface and tissu components.Based on the equivalent circuit, a transfer function is then defined and used in order to ensurethe delivery of the user defined waveform to the stimulation targets. A proof of concept hasbeen achieved with three steps : first on electronical components representing an in vivoimpedance, then into a saline solution and finally into an actual animal for in vivo validation.Those tests leaded to functionnal experiments prooving the interest of this novel method.The work is concluded by the specification and the simulation of an innovative multiapplicationsintegrated architecture using impedance data in order to adapt stimuli waveforms.
366

L'enrichissement protéique et les paramètres du procédé influencent-ils la structure chimique, les propriétés d'usage, la digestibilité et l'efficacité métabolique des fractions protéiques de spécialités pastières à base de légumineuses ? / Do protein enrichment and its process influence the chemical structure, properties, digestibility, and metabolic efficiency of legume pasta ?

Laleg, Karima 22 September 2016 (has links)
Afin d’approfondir les connaissances sur les liens entre la structure et les propriétés nutritionnelles de pâtes alimentaires, des pâtes de structures contrastées ont été produites en modifiant la formulation et/ou le procédé de fabrication. Leur structure a été caractérisée aux différentes échelles, puis les caractéristiques définies ont été reliées à la digestibilité des protéines et de l’amidon. Le remplacement partiel ou total de la semoule de blé dur par des farines de légumineuses dans la fabrication des pâtes a engendré des changements structuraux à plusieurs niveaux. Un affaiblissement marqué de la structure du réseau protéique proportionnel à la quantité de légumineuses incorporées a notamment été observé, conduisant à une amélioration de la digestibilité in-vitro des protéines. La digestibilité in-vitro de l’amidon était en revanche maintenue à son faible niveau voir même réduite. L’application de différentes températures de séchage a amplifié les modifications de la structure des pâtes enrichies en légumineuses. Ces différences s’atténuaient toutefois après cuisson, n’engendrant de fait aucune modification marquée de la digestibilité in-vitro des protéines entre une pâte cuite préalablement séchée à basse ou à très haute température. Les teneurs en facteurs antinutritionnels étaient réduites par le procédé de fabrication et de cuisson des pâtes. A quantité égale de protéines consommées, l’étude in-vivo a révélé une augmentation de la croissance et de l’efficacité azotée chez les rats nourris avec les pâtes mixtes blé/fèverole (65/35) par comparaison aux rats nourris aux pâtes 100% blé. L’assemblage blé/fèverole constituait un mélange protéique efficace pour la croissance des rats jeunes, probablement du fait de son profil équilibré en acides aminés, et de la structure affaiblie du réseau protéique. Par ailleurs, les différentes températures de séchage appliquées aux pâtes n’ont pas engendré de différence au niveau de la rétention azotée in-vivo. Les spécialités pastières développées au cours de ce travail de thèse sont jusqu’à trois fois plus riches en protéines et mieux équilibrées en acides aminés, comparativement à une pâte alimentaire classique. Ces spécialités pastières sont aussi appréciées que leurs homologues qui se vendent sur le marché. En outre, la recette mixte blé/légumineuses peut être adaptée à tout consommateur souhaitant diversifier ses apports en protéines, mais également à certaines populations spécifiques, notamment aux personnes âgées. La recette 100% légumineuses peut concerner les personnes intolérantes au gluten. Ces spécialités pastières pourraient de ce fait, trouver une large application à l’échelle industrielle. / In order to reinforce our knowledge about the links between structural and nutritional properties of pasta, pasta with contrasting structures were produced by modifying the formulation and/or the manufacturing process. Pasta structure was then characterized using a multiscale approach and linked to the digestibility of protein and starch fractions. The modification of pasta formulation by partial or total substitution of durum wheat semolina by legume flours changed pasta structure at various scales. A marked weakening in the structure of pasta protein network proportional to the level of legume protein incorporated was observed and related to an improvement of the in-vitro digestibility of pasta proteins. Interestingly the in-vitro starch digestibility was maintained at its low level or even reduced in mixed pasta. Changing pasta drying temperature amplified changes in the pasta structure. These differences, however, were reduced after cooking pasta resulting in unchanged in-vitro protein digestibility between cooked pasta dried at low or very high temperature. Anti-nutritional factors were also reduced by the manufacturing and cooking steps. In-vivo study revealed a better growth and nitrogen efficiency in rats consuming the same quantity of proteins from wheat/faba (65/35) mixed pasta in comparison with animals fed with 100% wheat pasta. This was probably related to the better amino acid balance, and to the weakened protein network in mixed pasta. The change in drying temperatures did not allow modifying protein retention. Pasta developed in this thesis are up to three fold richer in proteins than traditional wheat pasta, and more balanced in essential amino acids. Produced pasta are appreciated by the consumer as well as their counterparts found on the marked. Mixed wheat/legume may be adapted to the elderly people, whereas 100% legume pasta may be consumed by gluten intolerant subjects. Produced pasta may therefore find wide application at the industrial scale.
367

Contribution à la radiothérapie adaptative par analyse systématique de la fluence en entrée et de la dose en sortie du patient / Contribution to adaptative radiotherapy by systematic analysis of the entrance fluence and exit patient dose

Celi, Sofia 01 April 2016 (has links)
La radiothérapie moderne combine les techniques complexes et les traitements personnalisés, avec le risque que certaines évolutions et erreurs ayant lieu au cours de traitement passent inaperçues. Ces aléas peuvent entraîner des conséquences graves pour la santé du patient. Dans cette perspective, nous avons étudié le potentiel d'un système de dosimétrie in vivo de transit pour le suivi continu du patient et, par conséquent, la radiothérapie adaptative. L'expérience clinique et des tests de faisabilité ont permis de définir les axes de travail principaux: l'automatisation et la simplification du procédé d'analyse des contrôles. Les développements incluent la création d'une bibliothèque de données standard et une série d'analyses de causes racines, permettant ainsi de renforcer la précision du système, d'améliorer l'automatisation de sa mise en place et d'identifier des pistes pour une analyse efficace des résultats et pour la création d'outils supplémentaires facilitant le suivi et l'adaptation du traitement en routine clinique. / Modern radiation therapy combines complex techniques and personalized treatments, with the risk that certain evolutions and errors occurring during the course of the treatment might go unnoticed. These fluctuations may cause great damage to the health of the patient. In this perspective, we worked on the potential of a transit in vivo dosimetry system for continuous monitoring of the patient and, hereafter, adaptive radiotherapy. Our clinical experience and feasibility testing determined the main lines of work : automatization and simplification of the results analysis method. The developments included the creation of a golden data library and a series of root cause analyzes, allowing us to strengthen the accuracy of the system, to enhance the automatization of the setup and to identify tracks for an efficient analysis of the results and for the creation of additional analytical tools to facilitate the monitoring and adaptation of the treatments in clinical routine.
368

Parametry motility spermií ryb a celkové proteinové profily semenné plasmy během in vivo a in vitro uchování / Fish sperm motility parameters and total proteins profiles in seminal plasma during in vivo and in vitro storage

KOLEŠOVÁ, Anna January 2013 (has links)
The effect of gamete storage on sperm quality has received considerable attention in recent years. Previous studies have shown that spermatozoa stored in vivo or in vitro for a long time can lost their motility and fertilization capacity. Moreover, it have been concluded that male fertilization potential is highly dependent, not only on spermatozoa motility parameters, but also on organic components including protein composition of seminal plasma. On the other hand, spermatozoa motility and protein profiles of seminal plasma are highly dependent on conditions of storage. Therefore, additional data about effects of in vivo and in vitro storage on quality sperm parameters and protein composition of seminal plasma are essential for development of fish artificial reproduction methods. In the current work the influence of in vitro and in vivo storage on parameters of sperm motility, DNA integrity, antioxidant defensive system and seminal plasma protein composition were studied. As a conclusion, the results of this study provide new data on sperm quality and quantity parameters of chondrostean and teleost fish species with respect to in vivo and in vitro storage capacities, which should be beneficial for the development of aquaculture of these species. The data confirmed that protein patterns in seminal plasma varied during in vivo storage, depending on time of sperm collection. Furthermore, the altered proteins are probably involved in enzymatic pathways that regulate spermatozoa movement. In practice, the results presented in this thesis should help to improve management and optimize the development of protocols for artificial reproduction.
369

Caracterização biológica e prospecção terapêutica de Casearia sylvestris Swartz não incorporada e incorporada em sistema nanoestruturado na atividade anti-Helicobacter pylori / Biological characterization and therapeutic prospection of Casearia sylvestris Swartz not incorporated and incorporated in a nanostructured system in the anti-Helicobacter pylori activity

Spósito, Larissa [UNESP] 02 June 2017 (has links)
Submitted by LARISSA SPÓSITO null (lari_sposito@hotmail.com) on 2017-07-27T13:11:28Z No. of bitstreams: 1 Dissertação versão final encaminhada pós- PDF.pdf: 2246283 bytes, checksum: 9ebe4c751ba29fc9cf4495fdb7288e5e (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-07-31T18:31:53Z (GMT) No. of bitstreams: 1 sposito_l_me_arafcf.pdf: 2393152 bytes, checksum: cd33f70c4383729bdf5dc49ce9d3375f (MD5) / Made available in DSpace on 2017-07-31T18:31:54Z (GMT). No. of bitstreams: 1 sposito_l_me_arafcf.pdf: 2393152 bytes, checksum: cd33f70c4383729bdf5dc49ce9d3375f (MD5) Previous issue date: 2017-06-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O uso de produtos naturais na terapêutica convencional vem ganhando destaque nos últimos anos com relação a atividade antimicrobiana devido à alta taxa de efeitos tóxicos e ao excessivo crescimento do número de cepas multirresistentes aos antimicrobianos convencionais empregados na prática. Entre as novas triagens terapêuticas frente às afecções bacterianas, as infecções causadas pelo Helicobacter pylori merecem atenção especial, uma vez que estão diretamente relacionadas com quadros clínicos severos, como a gastrite crônica, úlcera péptica e câncer gástrico. A Casearia sylvestris Swartz é uma planta popularmente conhecida como guaçatonga ou erva-de-bugre, utilizada na medicina popular no tratamento de transtornos gástricos que nos últimos anos vem despertando interesse na comunidade científica, por suas importantes propriedades com potencial terapêutico como atividade anti-inflamatório, antiofídico, cicatrizante, citotóxica em linhagens de células tumorais e principalmente antiulcerogênica. Neste contexto, uma excelente alternativa para o aprimoramento dos parâmetros biodisponíveis dos extratos vegetais muito utilizada na atualidade é a incorporação destes em sistemas nanotecnológicos de liberação de fármaco para que o produto ativo tenha uma melhor ação. Deste modo, o presente trabalho teve por objetivo avaliar o potencial biológico antibacteriano in vitro do extrato etanólico, extrato aquoso, fração e subfrações das folhas de Casearia sylvestris Swartz, incorporar em um sistema de liberação de fármacos os derivados mais ativos e a partir dos resultados realizar o experimento in vivo contra a cepa ATCC 43504 de H. pylori. Os extratos foram preparados por infusão e maceração. Para as análises biológicas utilizamos a técnica de microdiluição para determinar a concentração inibitória mínima e o biofilme formado. O estudo foi desenvolvido aplicando-se metodologias in vitro e in vivo para elucidar o perfil antibacteriano pretendido, obtendo-se resultados satisfatórios, deixando esse estudo mais interessante, já que a literatura mostra que a C.sylvestris tem perfil anti-ulcerogênico. A partir desses resultados pudemos concluir que os derivados de C. sylvestris apresentaram estatisticamente atividades antibacterianas tanto in vitro como in vivo, sendo que a maioria dos derivados vegetais com exceção dos extratos aquosos, fração 1 e 3 e a subfração 17, tiveram alguma atividade frente ao micro-organismo. Essa atividade provavelmente esta relacionada aos diterpenos clerodânicos que estão em abundância nos derivados da C. sylvestris. A incorporação no sistema nanoestruturado não potencializou a atividade dos derivados vegetais como esperado na maioria dos teste, isto talvez seja pelo fato de a composição dos derivados vegetais e do sistema não serem compatíveis quimicamente. Desde que a literatura mostrou a atividade antiulcerogênica dos derivados vegetais da C. sylvestris, eles podem ser utilizados tanto na cicatrização das lesões como também para a erradicação do H. pylori. / The use of natural products in conventional therapeutics has been gaining highlight in recent years relative to the antimicrobial activity due to the high rate of toxic effects and the excessive growth of the number of multiresistant strains to he conventional antimicrobials used in practice. Among the new therapeutic screenings for bacterial diseases, infections caused by Helicobacter pylori deserve special attention, since they are directly related to severe clinical conditions, such as chronic gastritis, peptic ulcer and gastric cancer. Casearia sylvestris Swartz is a plant popularly known as guaçatonga or erva-de-bugre, used in popular medicine to the treatment of gastric disorders that in recent years has gained the interest of the scientific community due to its important properties with therapeutic potential as an anti-inflammatory, antiofidic, healing, cytotoxicity against tumor cells and mainly antiulcerogenic. In this context, an excellent alternative for the improvement of the bioavailability parameters of the vegetal extracts that is used today is the incorporation of these in nanotechnological systems of drug release so that the active product has a better action. Thus, the aim of this study was to evaluate the in vitro antibacterial potential of the ethanolic extract, aqueous extract, fraction and subfractions of the leaves of Casearia sylvestris Swartz, and incorporate into a drug delivery system the most active derivatives and from these results carry out the in vivo experiment against the H. pylori ATCC strain. The extracts were prepared by infusion and maceration. For the biological analyzes we use the microdilution technique to determine the minimum inhibitory concentration and the formed biofilm. The study was developed applying in vitro and in vivo methodologies to elucidate the antibacterial profile. From the results, we can conclude that the C. sylvestris derivatives showed statistically antibacterial activities both in vitro and in vivo. Most of the vegetal derivatives with the exception of aqueous extracts, fractions 1 and 3 and subfraction 17, had some activity against to the microorganism. This activity is probably related to clerodan diterpenes that are abundant in C. sylvestris derivatives. The incorporation into the nanostructured system did not potentiate the activity of the vegetable derivatives as expected in most tests, this is perhaps due to the fact that the composition of the plant derivatives and the system are not chemically compatible. Since the literature shows an antiulcerogenic activity of C. sylvestris derivatives, they could be used both for wound healing and for H. pylori eradication.
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Estudo in vivo da etiologia das lesões cervicais não cariosas / In vivo study of the etiology of noncarious cervical lesions

Livia Maria Dante Aguiar 13 September 2012 (has links)
As lesões cervicais não cariosas (LCNCs) são caracterizadas pela perda de estrutura dental no terço cervical dos dentes, que se origina a partir de mecanismos não relacionados com o processo de cárie. Este trabalho buscou investigar a correlação das LCNCs (severidade e acometimento), com os seguintes fatores: idade, sexo, dieta, hábitos parafuncionais, hábitos de higiene dental, distúrbios gástricos e aspectos oclusais. Foram estudados cinquenta pacientes (36 mulheres e 14 homens), com idades entre 20 e 62 anos (média de 40.9 anos). A avaliação consistiu na aplicação de questionários e exame clínico intraoral. Um índice de desgaste dental foi utilizado para classificação da severidade das LCNCs e do desgaste da borda incisal/face oclusal. Os resultados mostraram que os primeiros pré-molares (20,5%), segundos pré-molares (19,5%), caninos (14%), primeiros molares (13,9%) e segundos molares (11,6%) foram os dentes mais acometidos pelas LCNCs. Foi constatada correlação positiva entre idade e o percentual de dentes acometidos, ou seja, quanto maior a idade do paciente, maior foi o percentual de dentes acometidos com LCNC (p=0,003). Foi constatado que os pacientes com ingestão diária de alimentos e bebidas ácidas apresentaram relação significante com a severidade das LCNCs (p=0,038) e também apresentaram maior percentual de dentes acometidos pelas LCNCs (p=0,014). Não foi verificada relação significante entre as LCNCs (severidade e percentual de dentes acometidos) com o sexo dos pacientes, número de escovações diárias, apertamento dental, bruxismo, distúrbios gástricos, força durante a escovação e tipo de cerdas da escova. Quanto aos aspectos relacionados à oclusão, foi observada pequena correlação (r=0,079) entre o desgaste cervical e o desgaste da borda incisal/face oclusal. Em nenhum caso foi observada diferença estatística significante da severidade das LCNCs entre dentes que participam ou não do movimento de lateralidade. / Noncarious cervical lesions (NCCL) are characterized by loss of tooth structure in the cervical area, and originated by mechanisms unrelated to dental caries process. This study investigated the correlation of NCCL (severity and involvement) with the following factors: age, gender, diet, parafunctional habits, dental hygiene, gastric disorders and occlusal aspects. Fifty patients (36 female and 14 male) aged between 20 and 62 years (mean age of 40.9 years) were evaluated. The evaluation consisted of questionnaires and intraoral clinical examination. A Tooth Wear Index was used to classify the severity of NCCL and wear of the incisal/ occlusal surface. Results indicate that first premolars (20,5%), second premolars (19,5%), canine (14%), first molars (13,9%) and second molars (11,6%) were the teeth most affected by NCCL. There was correlation between the age of patients and the percentage of teeth affected, meaning that the older the patient, the higher the percentage of teeth affected with NCCL (p=0,003). Patients with daily intake of acidic foods and beverages presented a significant relationship with the severity of NCCL (p=0,038) and also a higher percentage of teeth affected by NCCL (p=0,014). There was no significant relationship between NCCL (severity and percentage of affected teeth) and gender of patients, number of daily brushings, teeth clenching, bruxism, gastric disorders, force applied during toothbrushing and characteristics of the toothbrushes. There was a small correlation (r=0,079) between NCCL and the wear of incisal/occlusal surface. Regarding the severity of NCCL, no significant statistical differences were observed between the teeth involved or not in the lateral excursive movement.

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