Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Thesis (Ph. D.)--University of Oklahoma. / Bibliography: leaves 205-212.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-09-08T13:48:31Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE_DANILO FONTES_PPGCF_UFPE.pdf: 6750693 bytes, checksum: ec0d551dfa4fb27855a7caf940d95aab (MD5) / Made available in DSpace on 2016-09-08T13:48:31Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE_DANILO FONTES_PPGCF_UFPE.pdf: 6750693 bytes, checksum: ec0d551dfa4fb27855a7caf940d95aab (MD5) Previous issue date: 2016-03-18 / FACEPE / Os hidróxidos duplos lamelares (HDL), também conhecidos como compostos tipo hidrotalcita, são materiais capazes de incorporar espécies biologicamente ativas, negativamente carregadas, na sua região interlamelar, de modo a neutralizar as cargas po-sitivas das lamelas, através do mecanismo de troca iônica. Além deste mecanismo, os HDL possuem alta capacidade de adsorção de materiais não iônicos e carregados positivamente, através de interações eletrostáticas e ligações de hidrogênio na sua vasta área superficial. Os HDL possuem ocorrência natural e também podem ser sintetizados em laboratório por rotas simples e de baixo custo, que permitem o isolamento de sólidos de alta pureza. O presente trabalho tem por objetivo a síntese e caracterização de HDL (CaAl-HDL e MgAl-Cl-HDL), e sua aplicação junto aos fármacos antiretrovirais Efavirenz (EFZ) e Zidovudina (AZT), e do anti-chagásico Benznidazol (BNZ). Os materiais obtidos foram caracterizados pelas técnicas de difração de raios-X (DRX), termogravimetria (TG), calorimetria exploratória diferencial (DSC), análise térmica diferencial (DTA), espectroscopia no infravermelho (IV), microscopia eletrônica de varredura (MEV), microscopia de luz polarizada e análise elementar de metais e de carbono, hidrogênio e nitrogênio (CHN). Foi possível observar que em sistemas com HDL de cálcio e alumínio (CaAl-HDL), obtido pelo método de evaporação do solvente, contendo até 30% de EFZ e até 20% do BNZ, o fármaco tornou-se uma molécula com características amorfas, perdendo seu caráter cristalino. Este fenômeno pôde ser comprovado através da ausência de planos cristalinos do fármaco no DRX, e também do seu ponto de fusão no DSC. Nos testes de liberação, estes sistemas obtiveram destaque no incremento de solubilidade, sendo a proporção HDL-EFZ 30% a mais promissora, com aumento de 558% do EFZ solúvel em relação ao fármaco isolado; e o sistema HDL-BNZ 20%, proporcionando 702% de aumento na solubilidade do fármaco. Desta maneira comprovou-se que associação entre o CaAl-HDL e o BNZ e EFZ (fármacos de baixa solubilidade) confere incremento de solubilidade, promovendo uma maior taxa de dissolução nos estudos in vitro. A solubilidade aquosa de um fármaco constitui requisito prévio à absorção e obtenção de resposta clínica, para a maioria dos medicamentos administrados por via oral. No sistema contendo MgAl-Cl-HDL e AZT, obtido pelo método de síntese por co-precipitação a pH constante, foi possível notar que, o fármaco tornou-se amorfo através da interação com a superfície do HDL, como evidenciado através do DRX, TG, IV e MEV. No estudo de liberação, foi possível obter um perfil de liberação prolongada do AZT, de 90% de fármaco em 24 horas de estudo. Os sistemas CaAL-HDL:EFZ e MgAl-Cl-HDL:AZT tornaram-se menos tóxicos quando comparados a seus respectivos fármacos isolados, enquanto o sistema CaAL-HDL:BNZ, não alterou a toxicidade do BNZ, quando testados em linhagem de macrófagos humanos. / Layered double hydroxides (LDH), also known as hydrotalcite compounds, are materials able to incorporate biologically active species, negatively charged, into the interlayer region, to neutralize the positive charges of the lamellae through the ion exchange mechanism. Besides this mechanism, LDH have a high adsorption capacity for positively charged non-ionic materials, through electrostatic interactions and hydrogen bonds on its vast surface area. LDH are found in nature and can also be synthesized by simple and low-cost routes, that allow for the isolation of high purity solids. This paper presents the synthesis and characterization of the LDH (CaAl-LDH e MgAl-Cl-LDH), its applications with the antiretroviral drugs efavirenz and zidovudine, and the anti-chagas drug Benznidazol. The materials were characterized by the techniques of x-ray diffraction (XRD), thermogravimetry (TG), differential scanning calorimetry (DSC), differential thermal analysis (DTA), infrared spectroscopy (IR), scanning electron microscopy (SEM), polarized light microscopy, and elemental analysis of metals and carbon, hydrogen and nitrogen (CHN). It was observed that in systems with CaAl-HDL, obtained by the solvent evaporation method, containing up to 30% of EFZ and 20% of BNZ, the drug became a molecule with amorphous characteristics, losing its crystalline character. This phenomenon could be demonstrated by the absence of the drug crystal planes in the XRD analysis, and also by its melting point in the DSC analysis. In the release experiments, these systems stood out because they promoted an increase in solubility, with LDH-EFZ 30% being the most promising, with an increase in the EFV solubility of 558% compared to the drug itself; and the LDH-BNZ 20% system providing a 702% increase in solubility. Thus, the association between CaAl-LDH and BNZ and EFZ (low solubility drugs) was proven to increase the solubility of these drugs, promoting a higher dissolution rate in in vitro studies. The aqueous solubility of a drug is a prerequisite for obtaining absorption and clinical response for most drugs administered orally. In the system containing MgAl-Cl-LDH and AZT, obtained by the method of co-precipitation at constant pH, it was noticeable that, after the synthesis, the drug became amorphous due to the interaction with the surface of the LDH, as evidenced by the XRD, TG, SEM, and IR analyses. In the release study, it was possible to obtain a profile of the prolonged release of AZT, 90% of the drug in a 24-hour experiment. The cell viability experiment showed that the CaAl-LDH:EFZ and MgAl-Cl-HDL:AZT systems became less toxic than the isolated drugs and the CaAl-HDL:BNZ system did not alter the toxicity of the drug itself, when tested in human macrophage lineage.

Human Immunodeficiency Virus Type 1 (HIV-1), the virus that causes Acquired Immunodeficiency Syndrome (AIDS), attacks the immune system leaving patients susceptible to opportunistic infections that eventually cause death. Highly Active Antiretroviral Therapy, HAART, is the current drug strategy used to combat HIV. It is a combination therapy that includes HIV-1 Reverse Transcriptase and HIV-1 Protease inhibitors. Drug resistant strains arise that evade current HAART treatments; therefore novel drugs are needed. HIV-1 regulatory proteins such as Tat, Rev, Nef, Vpr, Vpu, and Vif are attractive new drug targets. Of particular interest is the HIV-1 Vif protein and its cellular binding partner APOBEC3G. In the absence of HIV-1 Vif, APOBEC3G, a cytidine deaminase, is able to mutate the viral cDNA and render the virus noninfectious. HIV-1 Vif binds to APOBEC3G and targets it for proteosomal degradation through an interaction with a Cullin-RING ligase complex. Blocking the HIV-1 Vif APOBEC3G interaction would allow APOBEC3G to perform its antiviral function. An attractive strategy to target the HIV-1 Vif APOBEC3G interaction would be a structure-based one. To apply structure-based drug design approaches to HIV-1 Vif and APOBEC3G, I attempted to collect high resolution structural data on HIV-1 Vif and APOBEC3G. My attempts were unsuccessful because the milligram quantities of soluble protein required were not obtained. Therefore, in Chapter III I used chemical cross-linking and mass spectrometry to probe the structural topology of HIV-1 Vif obtaining low resolution structural data. Chemical cross-linking formed HIV-1 Vif multimers including dimers, trimers, and tetramers. Analysis of the cross-linked monomer revealed that HIV-1 Vif’s N-terminal domain is a well-folded, compact, globular domain, where as the C-teriminal domain is predicted to be disordered. In addition, disorder prediction programs predicted the C-terminal domain of HIV-1 Vif to be disordered. Upon oligomerization the C-terminal domain undergoes a disorder-to-order transition that not only facilitates oligomerization but may facilitate other protein-protein interactions. In addition, HIV-1 Vif oligomerization bring Lys34 and Glu134 in close proximity to each other likely creating one molecular surface forming a “hot spot” of biological activity. In Chapter IV I confirmed my low resolution structural data via peptide competition experiments where I identified peptides that can be used as scaffolds for future drug design. HIV-1 Vif oligomerization is concentration dependent. The HIV-1 Vif peptides Vif(29-43) and Vif(125-139) were able to disrupt HIV-1 Vif oligomerization, which confirms the low resolution structural data. HIV-1 Vif peptides Vif(25-39) and Vif(29-43) reduced the amount of APOBEC3G immobilized on the Protein A beads, reduced the amount of HIV-1 Vif interacting with APOBEC3G, or degraded APOBEC3G itself. These peptides could be used as scaffolds to design novel drugs that disrupt the function of HIV-1 Vif and or APOBEC3G. Therefore, low resolution structural data and peptide competition experiments were successful in identifying structurally important domains in HIV-1 Vif. They also provided insight into a possible mechanism for HIV-1 Vif function where a disorder-to-order transition facilitates HIV-1 Vif’s ability to interact with a diverse set of macromolecules. These data advance our structural understanding of HIV-1 Vif and they will facilitate future highresolution studies and novel drug designs.

No description available.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Felaktigt serienummer 1251. Härtill 4 uppsatser.

Orientadores: Pedro Paulo Corbi, André Luiz Barboza Formiga / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-24T12:00:41Z (GMT). No. of bitstreams: 1 Abbehausen_Camilla_D.pdf: 19393479 bytes, checksum: 3e6aaec4c411ad2e24a5f26226d19220 (MD5) Previous issue date: 2014 / Resumo: Complexos metálicos inéditos de paládio, platina, ouro e prata com diferentes classes de ligantes foram desenvolvidos. Dentre os ligantes selecionados estão a L-aliina (ali) e a N-acetil-L-cisteína (nac) que compreendem a classe dos aminoácidos, a 2-mercaptotiazolina (mtz), dentro da classe das tiazolidinas, a sulfadoxina (sfx), representante da classe das sulfonamidas, e ligantes N-heterociclos, piridino derivados com diferentes valores de pKa. Complexos de Pd(II) com L-aliina ([Pd(C6H11NO3S)2]), Ag(I) com N-acetil-L-cisteína ([Ag(C5H9NO3S)]), Ag(I) com sulfadoxina ([Ag(C12H13N4O4S)]), Au(I) com 2-mercaptotiazolina ([Au(CN)(C3H5NS2)]) e uma série de complexos trifenilfosfinoouro(I) com ligantes N-heterociclos ([Au(PPh3)L]+) foram sintetizados e caracterizados por um conjunto de análises químicas e espectroscópicas. Estudos in vitro das sua atividades antibacterianas e antitumorais foram também reali-zados. Atividades antibacterianas e antitumorais significativas foram encontradas para o complexo de Pd(II) com ali e o DNA se mostrou um alvo provável. O complexo Au(I) com mtz apresentou atividade antitumoral e antibacteriana bastante expressiva e uma investigação preliminar de seus mecanismos de ação também demonstrou que o DNA não parece ser o alvo destes compostos nas células. Os complexos de Ag(I) com nac e sfx apresentaram atividades antibacterianas significativas sobre cepas Gram-positivas e Gram-negativas. Os ligantes N-heterociclos 4-picolina (pic), 2-amino-4-picolina (NH2pic) e dimetilaminopriridina (DMAP) possuem valores de pKa crescentes, e foram selecionados para investigar o efeito do pKa na atividade biológica de complexos trife-nilfosfinoouro(I) do tipo [Au(PPh3)L]+, onde L = N-heterocíclico. Esta investigação foi realizada por avaliações in vitro de suas atividades antitumorais, além de estudos do acúmulo celular, do bloqueio do ciclo celular e por interações com biomoléculas como o DNA e proteínas dedos de zinco (zinc fingers, ZF). A atividade antitumoral foi expressiva e os estudos de suas interações com os ZF mostraram que a inibição pode ser modulada com a variação do tipo de proteína e do ligante N-heterociclo selecionado / Abstract: Novel palladium, platinum, gold and silver complexes with different classes of ligands were designed. The selected ligands were L-alliin (ali) and N-acetyl-L-cysteine (nac) which are aminoacids, 2-mercaptothiazoline (mtz), which belongs to the class of thiazolidines, sulfadoxine that represents the class of sulfonamides and N-heterocyclic pyridine derivatives, with different values of pKa. Complexes of Pd(II) with L-alliin ([Pd(C6H11NO3S)2]), Ag(I) with N-acetyl-L-cysteine ([Ag(C5H9NO3S)]), Ag(I) with sulfa-doxine ([Ag(C12H13N4O4S)]), Au(I) with 2-mercaptotiazoline [(Au(CN)(C3H5NS2)]) and a series of complexes of triphenylphosphinegold(I) with N-heterocyclic ligands ([Au(PPh3)L]+) were synthesized and characterized by a set of chemical and spectroscopic analyses. Antibacterial and antitumor activities in vitro were also studied. Significant antibacterial and antitumor activities were found for Pd(II) with ali, and the DNA is the probable biological target. The Au(I) with mtz complex presented noteworthy antitumor and antibacterial activities, and preliminary investigations of its biological mechanism showed that, the DNA is probable not a target of this complex in the cells. The silver complexes with nac and sfx presented significant antibacterial activities. The series of N-heterocyclic ligands 4-picoline (pic), 2-amino-4-picoline (NH2pic) and dimethylaminopyridine (DMAP) shows crescent pKa values and they were selected to investigate the pKa effect in the biological activity of the complexes triphenylphosphinegold(I) [Au(PPh3)L]+, which L = N-heterocyclic. This investigation was performed by evaluation of its antitumor activities in vitro, and also by studies of cell uptake, cell cycle arrest and by interactions with biomolecules as DNA and zinc finger proteins (ZF). The antitumor activity was expressive and the studies with ZF showed that the inhibition is dependent of the kind of protein and of the N-heterocyclic ligand / Doutorado / Quimica Inorganica / Doutora em Ciências

A presente tese traz, além de conceitos sobre a incorporação de tecnologias na saúde, uma abordagem da regulação institucional brasileira, junto com a descrição da história e do funcionamento dos medicamentos para tratamento da aids. Na segunda parte do trabalho, a partir de uma série de entrevistas, são descritos e analisados os percursos e processos da incorporação dos medicamentos anti-retrovirais no Brasil, a política pública na qual estão inseridos assim como a intermediação do programa governamental na introdução desta tecnologia. São identificadas também as instituições, grupos ou corporações - empresas farmacêuticas, Ministério da Saúde, médicos, pessoas que vivem com HIV e aids e Poder Judiciário, que atuam em três percursos da incorporação da tecnologia em questão. No percurso científico, há a validação da tecnologia através da realização de pesquisas com seres humanos e da elaboração de diretrizes clínicas. A fase regulatória da tecnologia, com seu registro oficial e sua etapa prescritiva, quando também ocorrem a promoção e marketing das empresas farmacêuticas e as ações judiciais que obrigam o poder público a fornecer os medicamentos, caracterizam o percurso transicional. Já no percurso mercantil conformam-se os aspectos relacionados à demanda, oferta, produção, preço, compra e venda dos anti-retrovirais. O estudo indica a ausência de uma atuação regulatória integrada e sistêmica do Estado sobre todos os percursos da incorporação dos anti-retrovirais. Também ressalta aspectos importantes para a melhor compreensão da introdução de novas tecnologias no Sistema Único de Saúde, ao mesmo tempo em que sugere a necessidade de novas estratégias que garantam a sustentabilidade da política brasileira de acesso universal ao tratamento da aids. / This thesis brings, in addition to concepts about the incorporation of technologies in health, an approach to the Brazilian institutional regulation, together with the description of the history and the functioning of medicines for the treatment of aids. In the second part of the work, based on a series of interviews, the courses and processes of the incorporation of antiretroviral drugs in Brazil are described and analyzed, just like the public policy in which they are inserted and the intermediation of the government program in the introduction of this technology. Also, we identify the institutions, groups or corporations - pharmaceutical companies, Surgeon General, doctors, people who live with HIV and aids and Judiciary Power -, who work in three courses of the incorporation of the technology in question. In the scientific course, there is the validation of the technology through research with human beings and the preparation of clinical guidelines. The regulatory phase of the technology, with its official register and its prescriptive stage, when the promotion and marketing of the pharmaceutical companies also occur, and also the legal actions that make the government provide the drugs, characterize the transition course. As for the mercantile course, it contains the aspects related to demand, supply, production, price, purchase and sale of antiretroviral drugs. The study shows the absence of an integrated, systemic regulatory action of the State on all the courses of the incorporation of the antiretroviral drugs. It also points out important aspects for better understanding the introduction of new technologies in the Unified Health System, whereas it suggests the need of new strategies in order to guarantee the sustainability of the Brazilian policy of universal access to the treatment of aids.