Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2018-07-04T16:56:32Z No. of bitstreams: 2 Dissertação - Deize Evangelista Araújo - 2016.pdf: 3131730 bytes, checksum: 8e60767c3408e2e5dff1bb07362a2c80 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-07-05T10:40:52Z (GMT) No. of bitstreams: 2 Dissertação - Deize Evangelista Araújo - 2016.pdf: 3131730 bytes, checksum: 8e60767c3408e2e5dff1bb07362a2c80 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-07-05T10:40:52Z (GMT). No. of bitstreams: 2 Dissertação - Deize Evangelista Araújo - 2016.pdf: 3131730 bytes, checksum: 8e60767c3408e2e5dff1bb07362a2c80 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-05-06 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Candidiasis is a serious health problem that affects a large number of people arround the world. The treatment of this disease is carried out with antifungals, which do not provide an effective cure, besides having resistance reports and high toxicity. In this context, it is necessary to study new antifungal compounds. In addition, the delivery form of the compounds in the living organism is also target of research, since the controlled release of compounds in biological systems can improve the mode of action of many drugs. Therefore, nanostructured systems, such as nanoparticles of chitosan, have been widely studied as controlled delivery of drugs. Then, this study aimed to evaluate the antifungal potential against Candida albicans of thiosemicarbazide (TSC), thiosemicarbazide-camphene (TSC-C) and chitosan nanoparticles incorporated with thiosemicarbazide (nanoTSC). In in vitro assays, the compounds were effective to inhibit nearly 100% of the fungus in concentrations of 1,37 mM to TSC, 0,02 mM to TSC-C and 0,27 mM to nanoTSC, and the most effective compound was TSC-C. NanoTSC and empty nanoparticles were also evaluated as to cell toxicity, and the concentration able to inhibit the fungus showed no cytotoxic activity. To confirm the values observed in in vitro assays, experiments were conducted using an animal model for vulvovaginal candidiasis. The results showed that TSC-C was more efficient in inhibiting C. albicans compared with TSC and nanoTSC, but was less effective than miconazole. However, histopathological analysis showed that the groups treated with the compounds under study, showed less intensity of damage to the vaginal epithelium and inflammatory infiltrates, compared with the positive control and the group treated with miconazole. Thus, the results suggest that TSC, nanoTSC and TSC-C are promising compounds in the treatment of vulvovaginal candidiasis. / A candidíase constitui um sério problema de saúde, pois é uma doença que atinge uma grande parcela da população mundial. O tratamento dessa doença é realizado com antifúngicos, que, muitas vezes, não garantem uma cura efetiva, além de apresentarem relatos de resistência e alta toxicidade. Nesse âmbito, faz-se necessário o estudo de novos compostos antifúngicos. Aliado a isso, a forma de liberação de fármacos no organismo vivo é também alvo de pesquisas, uma vez que a liberação controlada de fármacos em sistemas biológicos pode melhorar a forma de ação dos mesmos. Para tanto, os sistemas nanoestruturados, como as nanopartículas de quitosana, têm sido amplamente estudados como meios de liberação controlada de princípios ativos. Sendo assim, esse trabalho teve como objetivo a avaliação do potencial antifúngico de tiossemicarbazida (TSC), tiossemicarbazida-canfeno (TSC-C) e de nanopartículas de quitosana incorporadas com tiossemicarbazida (nanoTSC) contra Candida albicans. Nos ensaios in vitro, os compostos foram eficientes em inibir quase 100% do crescimento do fungo em concentrações de 1,37 mM para TSC, 0,02 mM para TSC-C e 0,27 mM para nanoTSC, sendo que o composto mais eficiente foi TSC-C. NanoTSC e nanopartículas vazias também foram avaliadas quanto a toxicidade celular, sendo que não foi observada atividade citotóxica na concentração capaz de inibir o crescimento do fungo. Para avaliar a atuação dos compostos in vivo, foram realizados experimentos utilizando um modelo animal para candidíase vulvovaginal. Os resultados mostraram que TSC-C apresentou maior eficiência no tratamento de candidíase vulvovaginal em comparação com TSC e nanoTSC, porém foi menos eficiente do que miconazol. No entanto, a análise histopatológica mostrou que os grupos tratados com os compostos em estudo, apresentaram menor intensidade de danos ao epitélio vaginal e infiltrados inflamatórios, se comparados com o controle positivo e com o grupo tratado com miconazol. Dessa maneira, os resultados apresentados sugerem que TSC, nanoTSC e TSC-C são compostos promissores para o tratamento da candidíase vulvovaginal.

As leishmanioses constituem um complexo de doenças causadas por protozoários do gênero Leishmania. São transmitidas pela picada de fêmeas parasitadas do gênero Phlebotomus e/ou Lutzomyia. A leishmaniose é uma doença zoonótica que afeta mais de 12 milhões de pessoas no mundo, e constituem uma preocupação para a saúde pública. A arginase de Leishmania é a primeira enzima da via das poliaminas e constitui um importante alvo terapêutico devido ao seu papel ativo na sobrevivência do parasita no hospedeiro. Neste trabalho, 78 moléculas sintéticas e naturais de diferentes grupos químicos foram testadas com objetivo de determinar a sua capacidade de inibição da enzima arginase recombinante de Leishmania (L.) amazonensis (ARG-LA). Foram considerados inibidores da ARG-LA os compostos que apresentaram uma inibição ≥ 70% a 100 µM. Os resultados revelaram 28,2 % de compostos com elevado potencial de inibição da ARG-LA, exibindo valores de IC50 na faixa micromolar. A cinética de inibição foi determinada pelo método de Dixon e Cornish-Bowden e revelou diferentes mecanismos de inibição enzimática. As moléculas sintéticas com potencial inibitório da ARG-LA correspondem aos ésteres e cinamidas biosintéticos, cinamidas derivados do ácido cafeico e pirazolopirimidinas. Além disso, foram testados 4 compostos naturais estruturalmente relacionados ao ácido caféico: piceatannol e 3 ácidos salvianólicos (A, B e D). Os resultados poderão servir de ponto de partida para o planejamento e síntese de novos fármacos para tratamento da leishmaniose, baseado na inibição da ARG-LA. / Leishmaniasis is a complex of diseases caused by Leishmania protozoa. They are transmitted by the bite of parasitized females of the Phlebotomus and/or Lutzomyia genus. Leishmaniasis is essentially a zoonotic disease, affecting more than 12 million people in the world and are a public health concern. Leishmania arginase is the first enzyme in the polyamine pathway and constitutes an important therapeutic target due to its active role in the parasite\'s survival in the host. In this work 78 compounds (synthetic and natural) of different chemical groups were tested to determine their ability to inhibit the recombinant Leishmania (L.) amazonensis arginase (LA-ARG). The IC50 and Ki were determined to the compounds that showed inhibition ≥ 70% at 100 µM. The results indicated that 28.2% of the compounds have a high potential for LA-ARG inhibition, with IC50 values in the micromolar range and different enzymatic inhibition mechanisms. The main synthetic groups with the high inhibitory potential of the enzyme corresponding to the caffeic acid derivatives, pyrazolopyrimidines, and the natural compounds piceatannol and salvianolic acids. These results indicate a potential for the synthesis of new drugs for the treatment of leishmaniasis, based on parasite arginase inhibition.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-18T11:21:28Z No. of bitstreams: 2 Dissertação - Lívia do Carmo Silva - 2014.pdf: 15880202 bytes, checksum: d2325694a6f7dbb08cd06f6d414870ea (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-18T11:24:59Z (GMT) No. of bitstreams: 2 Dissertação - Lívia do Carmo Silva - 2014.pdf: 15880202 bytes, checksum: d2325694a6f7dbb08cd06f6d414870ea (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-04-18T11:24:59Z (GMT). No. of bitstreams: 2 Dissertação - Lívia do Carmo Silva - 2014.pdf: 15880202 bytes, checksum: d2325694a6f7dbb08cd06f6d414870ea (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-03-12 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Paracoccidioidomycosis (PCM) is a systemic granulomatous human mycosis caused by fungi of the genus Paracoccidioides, geographically restricted to Latin America. Inhalation of spores and fragments of mycelia, infective forms of the fungus, is a common route of infection. The PCM treatment is performed with the prolonged administration of antifungal amphotericin B, the class of sulfonamides and azoles, which are toxic. In this sense, there is a need for the identification and characterization of novel targets for antifungal drugs in Paracoccidioides well as the search for new antifungal compounds from natural or obtained by chemical synthesis sources. In order to elucidate the response of Paracoccidiodies the thiosemicarbazide derivative of camphene, analysis of the transcriptional profile of the fungus was performed after 8 hs of contact with thiosemicarbazide. The results demonstrate that Paracoccidioides induced genes related to metabolism, cell cycle and DNA processing, Biogenesis of cellular components, cell transduction / signal, defense communication and virulence, energy, protein synthesis, protein fate (folding, modification, destination mechanism), translation, and proteins not classified. In addition intensely inhibited genes related to protein synthesis. In order to evaluate the biological activity of six compounds synthesized by the reaction of Morita- Baylis- Hillman was realized to minimal inhibitory concentration assays, cytotoxicity and hemolytic potential, interaction with antifungal agents already used in the treatment of PCM. The Morita-Baylis-Hillman adducts interfered on fungal growth in a dose-dependent manner, promoted the decreased activity of mitochondrial dehydrogenases and showed synergistic interaction with bactrim. No hemolytic activity was observed despite the high toxicity found and no inhibition of Malate sintase. The results demonstrate the potential of these compounds as candidates antifungal. / Paracoccidioidomicose (PCM) é uma micose humana granulomatosa sistêmica causada por fungos do gênero Paracoccidioides, geograficamente restrita aos países da América Latina. A inalação de conídios e fragmentos de micélios, formas infectantes do fungo, é a frequente via de infecção. O tratamento da PCM é realizado com a administração por tempo prolongado de antifúngicos anfotericina B, sulfonamidas e da classe dos azólicos, os quais são tóxicos. Nesse sentido, surge a necessidade de identificação e caracterização de novos alvos para drogas antifúngicas em Paracoccidioides bem como a busca de novos compostos antifúngicos obtidos de fontes naturais ou através de síntese química. Com o objetivo de elucidar a resposta de Paracoccidiodies à tiossemicarbazida derivada do canfeno, foi realizada a análise do perfil transcricional do fungo após 8 horas de contato com tiossemicarbazida. Os resultados demonstram que Paracoccidioides induziu genes relacionados ao Metabolismo, ciclo celular e processamento de DNA, Biogêneses de componentes celulares, mecanismo de transdução de comunicação celular / sinal, defesa e virulência, energia, síntese de proteínas, destino de proteínas (Enovelamento, modificação pós-traducional), transcrição e proteínas não classificadas. Em adição inibiu intensamente genes relacionados à síntese proteica. Com o objetivo de conhecer a atividade biológica de seis compostos sintetizados através da reação de Morita-Baylis-Hillman, foi realizado ensaios de concentração inibitória mínima, citotoxidade e potencial hemolítico, interação com antifúngicos já utilizados no tratamento da PCM. Os adutos Morita-Baylis-Hillman interferiram no crescimento do fungo de forma dose-dependente, promoveu a diminuiu a atividade de desidrogenases mitocondriais e apresentou interação sinérgica com Bactrim. Nenhuma atividade hemolítica foi observada apesar da alta toxicidade encontrada e nenhuma inibição da malato sintase. Os resultados demostram a potencialidade destes compostos como candidatos a antifúngicos.

<p>U ovoj doktorskoj disertaciji izloženi su rezultati&nbsp;analize eksperimentalno i teorijski dobijene&nbsp;raspodele gustine naelektrisanja dva derivata&nbsp;tiosemikarbazida, 4-metil-3-tiosemikarbazida&nbsp;(MeTSC) i 4-metil-3-tiosemikarbazon 2-piridinformamida (TSC4). &nbsp;Analiza&nbsp;eksperimentalno dobijene gustine naelektrisanja je&nbsp;zasnovana&nbsp; na preciznim &nbsp;podacima dobijenim&nbsp;difrakcijom rendgenskog zračenja visoke&nbsp;rezolucije. Teorijska istraživanja bazirana su na&nbsp;teorijskim strukturnim faktorima dobijenim&nbsp;primenom programa CRYSAL09 polazeći od&nbsp;geometrije&nbsp; molekula određene nakon multipol&nbsp;utačnjavanja eksperimentalno dobijene gustine&nbsp;naelektrisanja. Za opisivanje eksperimentalne i&nbsp;teorijske ukupne elektronske gustine kori&scaron;ćen je&nbsp;Hansen-Coppens-ov multipol-model.&nbsp; Takođe je&nbsp;urađena i topolo&scaron;ka analizahemijskih veza i&nbsp;interakcija &nbsp;i ispitivana su elektrostatička svojstva&nbsp;atoma sumpora.</p><p>Analizom eksperimentalne gustine&nbsp;naelektrisanja kristalnih struktura MeTSC i TSC4&nbsp;uočeno je da deformaciona gustina slobodnih&nbsp;elektronskih parova S atoma ima &nbsp;oblik torusa, da&nbsp;je unutar njega raspodela elektronske gustine&nbsp;nehomogena i da položaj samog torusa može biti&nbsp;ortogonalan (SalTSC) ili pod uglom (MeTSC,&nbsp;<br />TSC4).&nbsp; Na osnovu raspodele deformacione&nbsp;gustine i elektrostatičkog potencijala, kao &nbsp;i na&nbsp;osnovu topolo&scaron;ke analize ukupne eksperimentalne&nbsp;gustine naelektrisanja &rho;_ktv&nbsp; i njenog Laplasijana &nabla;²&rho;_ktv zaključeno je da atom sumpora ima izrazitu&nbsp;fleksibilnost i sposobnost da prilagodi svoju&nbsp;elektronsku gustinu slobodnih elektronskih &nbsp;parova&nbsp;prostornom rasporedu donornih grupa koje&nbsp;učestvuju u interakcijama sa S akceptorom.&nbsp; U&nbsp;kristalnim strukturama MeTSC i TSC4 utvrđeno&nbsp;je da S atom istovremeno gradi četiri, odnosno&nbsp;prosečno &scaron;est međumolekulskih interakcija.</p><p>U cilju upotpunjavanja eksperimentalnih&nbsp;rezultata analizirana je teorijski dobijena gustina&nbsp;naelektrisanja oba molekula, a zatim su ispitivane&nbsp;karakteristike sumpora kao akceptora i to u&nbsp;sistemima različite složensti polazeći od&nbsp;izolovanih monomera, preko izdvojenih dimer do&nbsp;kristalnogokruženja. Ovom analizom je utvrđeno&nbsp;da se simultanim angažovanjem S atoma u vi&scaron;e&nbsp;interakcija ne umanjuje njegova akceptorska&nbsp;sposobnost.</p><p>Vodonične vezekoje uključuju S akceptor su&nbsp;ispitivane sa aspekta &nbsp;energijskih svojstava dimera&nbsp;koji suprisutni u MeTSCi TSC4, kaoi u dodatno&nbsp;konstruisanim&nbsp; sistemima&nbsp; MeTSC/MeOH&nbsp; i&nbsp;aceton/MeOH. Energijske&nbsp; karakteristike&nbsp; su&nbsp;proučavane u pogledu elektrostatičke energije&nbsp;interakcije (E_es) i kohezione energije(E_coh). Za&nbsp;<br />dva odabrana&nbsp; MeTSC/MeOH i aceton/MeOH&nbsp;sistema je primenjena metoda &nbsp;kuplovanih klastera&nbsp;kao&scaron;to&nbsp; je&nbsp;<em> ab initio</em>&nbsp; CCSD(T)&nbsp; metod.&nbsp; Za&nbsp;MeTSC/MeOH sistem je &nbsp;urađena potpuna&nbsp;optimizacija i za tako dobijenu ravnotežnu&nbsp;geometriju je izračunata energija sistema&nbsp;∆E_CCSD(T),CBS.</p> / <p>In this dissertation the analysis of the experimental and theoretically obtained electron &nbsp;density of two derivatives of thiosemicarbasides, 4-methyl-3-thiosemicarbaside (MeTSC) and 4-methyl-3-thiosemikabazone 2-piridinformamide (TSC4) are presented.&nbsp; The analysis of experimentally obtained electron density is based on &nbsp;accurate X-ray diffraction data of high resolution. Theoretically calculated electron densities are obtained from periodic quantum mechanical calculation using CRYSTAL09 and the accurate structural parameters from high resolution X-ray&nbsp;experiment. For the description of the theoretical and experimental electron density the Hansen-Coppens multipol model was used. Further topological analysis of chemical bonds and interactions was performed in order to explain the electrostatic properties of sulfur.</p><p>In this work it has been observed that in the experimentally obtained electron density of the MeTSC and TSC4 crystal structures, the deformational electron density of sulfur free electron pairs forms a toroidal shape. Further, this torus is not homogeneously filled but shows pronounced local accumulations and its position can be either orthogonal (like in SalTSC) or tilted (MeTSC, TSC4). Based on the distribution of the&nbsp;deformational electron&nbsp; density and electrostatic potential, as well as the topological analysis of the total electron density &rho;_ktv and its Laplasian &nabla;²&rho;_ktv&nbsp;it can be concluded that the S atom has a remarkable flexibility and ability to adapt his deformation electron density of free electron pairs into toruses corresponding to the position of donor groups surrounding him. In the crystal structures of MeTSC and TSC4 it was determined that the S atom participates in four and six interactions, respectively.</p><p>In order to supplement&nbsp; the experimentally obtained results a theoretically calculated electron density of both molecules (MeTSC and TSC4) was performed and the properties of the S atom as a hydrogen acceptor have been studied. The analysis was &nbsp;performed on systems of various complexity, starting with isolated monomers, then on &nbsp;dimers and up to the whole crystal packing. From this work it has been concluded that &nbsp;the acceptor capabilities of the S atom are not diminished with the increasing number &nbsp;of interactions.&nbsp;&nbsp;&nbsp;&nbsp;</p><p>The hydrogen bonding involving thioureido S&nbsp;acceptor is also investigated in terms of the energetic properties of the MeTSC and TSC4 dimers existing in the crystal structure, and additional MeTSC/MeOH and acetone/MeOH systems. Energetic features were thoroughly studied through electrostatic interactions energies (E_es) and &nbsp;cohesive energies (E_coh). For two selected MeTSC/MeOH and acetone/MeOH systems an ab initio approach&nbsp;employing the coupled-cluster singles and doubles augmented by a perturbational correction for connected triple excitations (CCSD(T)) method were applied. Finaly, for MeTSC/MeOH system full geometry optimization was &nbsp;performed and for resulting equilibrium geometry the energy of the system (∆E_CCSD(T),CBS) was calculated.</p>