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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.
11

Efeito do diclofenaco sodico sobre a concentração serica e tecidual da amoxicilina e sobre a infecção estafilococica : estudo in vivo, em ratos

Simões, Roberta Pessoa 12 August 2018 (has links)
Orientador: Francisco Carlos Groppo / Dissertação (mestrado) Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-12T01:52:09Z (GMT). No. of bitstreams: 1 Simoes_RobertaPessoa_M.pdf: 1951478 bytes, checksum: fa986a3125f61b41fa59a6ea91b73746 (MD5) Previous issue date: 2000 / Resumo: O presente trabalho teve por objetivo observar o efeito da amoxicilina, do diclofenaco sódico e da associação de ambos sobre a infecção estafilocócica induzida em tecidos granulomatosos, em ratos. Também foram avaliadas as concentrações sérica e teciduais da amoxicilina, observando o efeito da associação do diclofenaco sódico sobre as mesmas. Trinta animais receberam implantes de quatro esponjas de poliuretana subcutâneamente no dorso e, após 14 dias, dois dos tecidos resultantes (posicionados caudalmente) receberam 0,5mL de um inóculo de 108 ufcjmL de S. aureus ATCC 25923. Dois dias após, os animais foram divididos em grupos de seis, os quais receberam uma dose única de amoxicilina 50mgjkgjvo (grupo 1), amoxicilina 25 mg/kg/vo (grup02), diclofenaco sódico 2,5mg/kg/im (grupo 3), diclofenaco sódico 2,5mg/kg/im + amoxicilina 50mg/kg/vo (grupo 4) e soro fisiológico 1mLjanimal/vo (controle). Após 6h, dois tecidos granulomatosos (posicionados em direção à cabeça) e 10 _L de soro sangüíneo foram obtidos de cada animal, os quais foram dispostos em diferentes placas com MHA semeado com 108 ufcjmL de S. aureus ATCC 25923. Após incubação, foram medidos os halos de inibição proporcionados pelos tecidos granulomatosos e pelo soro sangüíneo. Dez microlitros, provenientes dos tecidos infectados após dispersão com auxílio de sonicador em tubos de ensaio contendo 10m L de NaCI foram distribuídos em placas contendo ágar salt manitol; permitiram a contagem do número de microrganismos em cada grupo. Os resultados mostraram concentrações teciduais de amoxicilina de 6,6 I-Ig/g para o grupo 1; 2,8I-1g/g para o grupo 2 e 0,8 I-Ig/g para o grupo 4. As concentrações séricas do antimicrobiano encontradas foram 11,6 I-Ig/mL para o grupo 1; 5,4I-1g/mL para o grupo 2 e 1,3I-1g/mL para o grupo 4. Não foram observadas diferenças estatisticamente significantes entre o número de microrganismos dos grupos 1, 2 e 4. Entretanto, estes foram significativamente diferentes do controle e do grupo 3, os quais foram diferentes entre si. Foi concluído que, embora o diclofenaco sódico (grupo 4) tenha diminuído a concentração tecidual da amoxicilina, a concentração resultante foi suficiente para permitir uma redução do número de microrganismos viáveis similar à observada nos grupos 1 e 2 / Abstract: The aim of this work was to observe the effect of the amoxicillin, sodium diclofenac and amoxicillin plus sodium diclofenac against staphylococcal infection in granulomatous tissues. Four polyurethane sponges placed under the back skin of thirty rats induced these tissues. After 14 days two tissues (tall position) received 0.5 mL of 108 ufc of S. aureus ATCC 25923/mL. Two days after, the animais were divided into five groups of six each. Group 1 received an only dose of amoxicillin 50mgjkgjpo, group 2 received amoxicillin 25mgjkgjpo, group 3 received sodium diclofenac 2.5mgjkgjim, group 4 received sodium diclofenac 2.5mg/kg/im plus amoxicillin 50mg/kg/po, and group 5 (control group) received NaCI 1mLjpo. After six hours of drug administration, two tissues of each animal were removed. Blood was collected from cervical plexus and centrifuged. Then, 10j.JL of serum were placed on paper disks. These disks and tissues were placed on dishes with Mueller Hinton agar inoculated with 108 ufc of Staphylococcus aureus/mL The dishes were incubated over 18 hours, and the inhibition zones were measured. The infected granulomatous tissues were placed in 10mL of NaCI, and dispersed by sonic system. Ten microliters of this suspension were spread on salt manitol agar dishes. The resulting microorganisms were counted after the incubation. Results showed tissue concentrations of amoxicillin of 6.6 ug/g for group 1; 2.8ug/g for group 2, and 0.8 ug/g for group 4. Serum concentration of amoxicillin showed 11.6 ug/mL for group 1; 5.4ug/mL for group 2, and 1.3ug/mL for group 4. Statistically significant differences among the number of microorganisms groups 1, 2, and 4 were not observed. However, these previous groups were statistically different from groups 3 and 5, which were statistically different from each other. It was concluded that, although sodium diclofenac (group 4) reduced amoxicillin concentration in the tissue, the resulting concentration was enough to reduce the count of microorganism. Also, the number of microorganisms of group 4 was similar to the one observed in groups 1 and 2 / Mestrado / Farmacologia, Anestesiologia e Terapeutica / Mestre em Odontologia
12

Synthèse, fonctionnalisation et applications de métallo-NHC du groupe 11 / Synthesis, functionalisation and applications of coinage metals N-Heterocyclic carbenes

Gibard, Clémentine 05 December 2014 (has links)
Les carbènes N-hétérocycliques (NHC) sont utilisés comme ligands pour les métaux de transition. Les complexes résultants présentent principalement des applications en catalyse, ainsi que dans la conception de nouveaux candidats médicaments. Dans ce travail, nous discuterons une simplification des méthodes de synthèse des sels d’imidazoliniums, ainsi que des complexes Cu- et Ag-NHC. L’ammoniaque est utilisé ici à la fois comme milieu solubilisant des espèces métalliques et comme base pour la déprotonation des sels d’imidazoli(ni)ums fournissant une métallation douce, rapide et simple. La fonctionnalisation des NHC, dans des positions définies, permet une modulation de certaines de leurs caractéristiques sans impacter les propriétés remarquables de leurs complexes. De nouvelles méthodes de fonctionnalisation, par cycloaddition azoture-alcyne en périphérie des noyaux aromatiques, ont été mises au point. Ceci mène à l’introduction de trois stratégies synthétique : pré-, post- et auto-fonctionnalisation. La stratégie de pré-fonctionnalisation de précurseurs permet l’accès à des métallo-NHC du groupe 11, dont les propriétés de solubilité peuvent être facilement modifiées. Des réactions thermiques d’Huisgen et de SPAAC sont réalisables directement sur les complexes Au-NHC modifiés par des azotures, et sont désignés comme post-fonctionnalisation. Des réactions dites d’auto-fonctionnalisations entre un complexe Cu-NHC possédant un azoture et des alcynes divers, permettent l’introduction, par exemple, de biomolécules sensibles sans étapes de protection/déprotection. Enfin, les complexes Cu-NHC fonctionnalisés avec des groupements hydrosolubilisants ont été étudiés en tant que catalyseurs de cycloaddition de CuAAC dans des milieux biocompatibles, tandis que les Ag-NHC fonctionnalisés avec des groupements lipophiles présentent une activité antibactérienne. / N-heterocyclic carbenes (NHCs) have been used very frequently as ligands for the preparation of transition metal-based catalysts as well as drug candidates. This work will present a simplification of imidazoliniums synthesis and a new preparation of Ag-, Cu-NHC complexes. Aqueous ammonia will be used for the solubilisation of metallic species and as a base for the deprotonation of imidazoli(ni)um salts providing a mild, quick and easy metallation procedure. The functionalisation of NHC ligands, in definite positions, allows the modulation of some of their characteristics without interfering with the remarkable properties of their complexes. New functionalisation strategies by azide-alkyne cycloaddition reaction at the periphery of aromatics cores, were developped. This can be described by the following three synthetics strategies: pre-, post- and auto-functionalisation. Pre-functionnalisations strategy of precursors allows the synthesis of coinage metal-NHC complexes, for which variation of solubility is easily obtained. Thermal Huisgen reactions and SPAAC are achievable on the Au-NHC azide modified complexes directly, in a post-functionalisation pathway. Furthermore, the post-functionnalisation strategy was extended to Cu-NHC complexes resulting in an auto-functionalisation process. This allowed subsequently the introduction of sensitive biomolecules without protection/deprotection steps. Finally, water soluble Cu-NHCs complexes were used as CuAAC catalyst in bio-compatible media. Lipophilic Ag-NHCs complexes were tested as antibacterials (antibiofilm and growth inhibition activities).
13

Etude phytochimique de quelques plantes extrêmophiles tunisiennes et exploration de leurs activités biologiques / Phytochimie study of some Tunisian extremophilic plants and exploration of their biological activities

Sahli, Ramla 13 July 2017 (has links)
L'approche écologique est une des stratégies de recherche de substances actives. Cette approche porte sur les plantes extrêmophiles, incluant les plantes halophytes et xérophytes, végétaux natifs des biotopes salins et arides. De par leur capacité à subsister dans un environnement contraignant, qui se traduit, entre autres, par l'acquisition d'un système antioxydant puissant, elles se révèlent être des réservoirs en biomolécules, notamment en composés phénoliques. Dans cette étude, nous nous sommes ainsi intéressés à huit plantes halophytes et xérophytes Tunisiennes pouvant avoir des activités biologiques en santé humaine et en santé du végétal. Limonium virgatum (Willd.) Fourr. (Plumbaginaceae), plante halophyte, a montré des activités antioxydantes et antibactériennes intéressantes qui se trouvent respectivement liées à un contenu en polyphénols élevé et à la présence de phénylpropanoïdes. Cirsium scabrum (Poir.) Bonnet & Barratte (Asteraceae), plante xérophyte, a montré une activité cytotoxique selective envers la lignée cancéreuse J774 mettant en avant l'efficacité de triterpènes de type cycloartane ; mais également un pouvoir antibactérien sur des souches de Dermabacter hominis, qui serait lié à la présence de flavones glycosylées. Juncus maritimus Lam. (Juncaceae), plante halophyte, s'est montrée être une source de dérivés phénanthréniques à activités originales. Le juncunol, a montré une activité prometteuse sur une souche de Streptococcus pyogenes résistante à l'amoxicilline. L'effusol actif sur le pathogène de la septoriose du blé (Zymoseptoria tritici), serait stimulé dans les rhizomes de la plante en conditions de salinité élevées. Enfin, le dehydrojuncusol s'est montré être un nouvel inhibiteur de la réplication du virus de l'hépatite C, capable d'agir sur des formes de résistance à certains traitement disponibles sur le marché. / Research strategies of active natural products include ecological approaches. Extremophile plants, and in particular, halophytes and xerophytes, salt and drought-resistant plants, are a case in point. As they develop an arsenal of adaptation responses, including a powerful antioxidant system, they prove to be a promising source of biomolecules, especially in phenolic compounds. In this study, an assessment of biological activities was carried out on eight Tunisian halophyte and xerophyte plants that would offer new applications in public health-care, as well as in agriculture. Limonium virgatum (Willd.) Fourr. (Plumbaginaceae), a halophyte plant, showed interesting antioxidant and antibacterial activities in accordance to a high polyphenol content and to the presence of phenylpropanoides, respectively. Cirsium scabrum (Poir.) Bonnet & Barratte (Asteraceae), a xerophyte plant, revealed a cytotoxic potential involving cycloartane-type triterpenes, and a promising activity against Dermabacter hominis strains which is linked to the presence of glycosylated flavones. Juncus maritimus Lam. (Juncaceae), a halophyte plant, should be referred to a source of phenanthrene derivativeswith original biological activities. Juncunol showed a high activity against an amoxicillin-resistant strain of Streptococcus pyogenes. Effusol was highly active against the wheat pathogen (Zymoseptoria tritici), for which high salinity conditions would stimulate its activity in the rhizomes of the plant. Most interestingly, dehydrojuncusol, has been introduced as a novel inhibitor of hepatitis C virus replication that is effective against resistant mutants for which some treatments available on the market became ineffective.
14

Synthèse d'analogues nucléotidiques visant l'inhibition de la Thymidylate Synthase Flavine-Dépendante / Synthesis of nucleotides analogs targeting the inhibition of Flavin-Dependent Thymidylate Synthase

Chevrier, Florian 24 October 2018 (has links)
Ces dernières années, l’OMS a émis un signal d’alarme à propos de l’occurrence majeure de résistance bactérienne qui constitue un problème de santé publique global. A ce titre, la recherche de nouvelles cibles enzymatiques et le développement de nouveaux antibactériens ciblant ces dernières de manière sélective constitue alors un enjeu actuel impératif. La mise en évidence d’une nouvelle enzyme de la famille des thymidylates synthases par l’équipe de Myllykallio en 2002 et son étude a permis de faire de cette dernière une cible de choix pour la conception de nouveaux antibactériens par sa présence exclusive chez des bactéries pathogènes pour l’Homme, sa non-similarité structurelle avec l’enzyme thymidylate synthase classique et son mécanisme particulier mettant en jeu un couple de cofacteurs oxydo-réducteurs(NADPH/FAD). Ce manuscrit, divisé en trois grandes parties, s’intéresse dans un premier temps à la synthèse métallo-catalysé de nouveaux analogues nucléotidiques du FAD substitué sur l’azote centrale par une chaîne acyclique de type alkényle phosphonate. Dans un second temps, le manuscrit traite de la translation de cette même chaîne latérale sur l’azote N1 couplée à un large panel de base hétéroaromatiquebicyliques ou tricycliques par deux réactions clés : une alkylation régiosélective en conditions deVorbrüggen et une étape de métathèse croisée. Enfin, la troisième partie porte sur la préparation d’acyclonucléosides comportant un motif d’intérêt de type gem-difluoromethylphosphonate connu comme étant un mime isostérique et isoélectronique du groupement phosphate. L’incorporation de ce motif a permis la synthèse de petite librairie d’ANPs inédits à visée anti-FDTS et anti-virales. / In recent years, WHO has warned against the major occurrence of bacterial resistance as a global public health problem. As such, the search for new enzymatic targets and the development of new antibacterials targeting them selectively is therefore an imperative challenge. The discovery of a new enzyme among the family of thymidylate synthases by Myllykallio’s team in 2002 and its study has made it a prime target for the design of new antibacterials by its sole presence in pathogenic bacteria, its structural dissimilarity with the classical thymidylate synthase enzyme and its singular mechanism involving a pair of oxido-reducingcofactors (NADPH / FAD).This manuscript, divided into three main parts, is initially interested in the metallocatalytic synthesis of new nucleotide analogues of FAD substituted on the central nitrogen by analkenyl phosphonate acyclic chain. In the second part, the manuscript deals with the translation of this same side chain on nitrogen N1 on a large panel of bicylic or tricyclic heteroaromatic base through two keyreactions: a regioselective alkylation under Vorbrüggen conditions and a cross metathesis step. Finally, th ethird part relates to the preparation of acyclonucleosides comprising a gem-difluoromethylphosphonatefunctional group which is known to be an isosteric and isoelectronic mimic of the phosphate group. The incorporation of this moeitie has allowed the synthesis of a small library of novel ANPs for anti-FDTS andanti-viral purposes.
15

Caracterização química e atividade biológica de extratos etanólicos de Curcuma longa e Bixa orellana /

Guedes, Juliana Campos Diniz January 2019 (has links)
Orientador: Elisa Helena Giglio Ponsano / Resumo: O objetivo deste estudo foi investigar a composição química e as atividades antimicrobiana e antioxidante dos extratos etanólicos de Curcuma longa e Bixa orellana, na busca por substituintes aos aditivos sintéticos utilizados na indústria de alimentos. Pela espectrometria de massa (GC-MS) foram identificados bisdemetoxicurcumina, demetoxicurcumina e curcumina no extrato de C. longa e prunina e naringenina no extrato de B. orellana. C. longa apresentou atividade antimicrobiana frente a Clostridium sporogenes e Staphylococcus aureus, com concentração bactericida mínima (CBM) de 25 mg/mL e 156 µg/mL, respectivamente. O extrato de B. orellana apresentou CBM de 50 mg/mL para C. sporogenes e 625 µg/mL para S. aureus. Nenhum dos extratos apresentou atividade bactericida para Escherichia coli e Salmonella Typhimurium. A atividade antioxidante dos extratos foi evidenciada pelos métodos Poder Antioxidante por Redução Férrica (FRAP) e Capacidade de Absorção do Radical Oxigênio (ORAC). O extrato de B. orellana apresentou maior atividade antioxidante pelos métodos FRAP e ORAC (277,70 e 455,17 mM trolox equivalente/g, respectivamente) do que o extrato de C. longa (129,74 e 217,98 mM trolox equivalente/g, respectivamente). Os efeitos biológicos dos extratos etanólicos de C. longa e B. orellana revelados no presente estudo apontaram seu potencial para a utilização na indústria de alimentos como uma alternativa aos aditivos sintéticos. / Abstract: The objective of this study was to investigate the chemical composition and the antimicrobial and antioxidant activities of Curcuma longa and Bixa orellana ethanolic extracts, in the search for alternatives to the synthetic additives used in the food industry. Mass spectrometry (GC-MS), identified bisdemethoxycurcumin, demethoxycurcumin and curcumin in the extract of C. longa and prunin and naringenin in the extract of B. orellana. C. long showed antimicrobial activity against Clostridium sporogenes and Staphylococcus aureus, with a minimum bactericidal concentration (MBC) of 25 mg/mL and 156 μg/mL, respectively. MBC of B. orellana extract was 50 mg/mL for C. sporogenes and 625 μg/mL for S. aureus. None of the extracts showed bactericidal activity against Escherichia coli and Salmonella Typhimurium. The antioxidant activity of the extracts was evidenced by the methods Iron Reduction Antioxidant Power (FRAP) and Oxygen Radical Absorption Capacity (ORAC). B. orellana extract had higher antioxidant activity by FRAP and ORAC (277.70 and 455.17 mM trolox equivalent/g, respectively) than C. longa extract (129.74 and 217.98 mM trolox equivalent/g, respectively). The biological effects of C. longa and B. orellana ethanolic extracts revealed in this study indicated their potential as an alternative to synthetic additives used in the food industry. / Mestre

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