Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-15T17:02:45Z No. of bitstreams: 1 2009 - William Pereira.pdf: 3794972 bytes, checksum: 64fbf9758bbf44329031caf3b369b79a (MD5) / Made available in DSpace on 2017-02-15T17:02:45Z (GMT). No. of bitstreams: 1 2009 - William Pereira.pdf: 3794972 bytes, checksum: 64fbf9758bbf44329031caf3b369b79a (MD5) Previous issue date: 2009-10-22 / CAPES / The present study has two specific phases: Early, was studied the isathine irradiation with the presence of diisopropil-phosphoril-dimethylidrazone (diisopfh), in chloroform, at room temperature and 300nm. The structure of photo-product was elucidated by GC/MS, IR, NMR 1H, 13C and 31P, as well as hety-cosy, homo-cosy and other techniques. The proposal mechanism involve a bi-radical from triplet excited state of isathine that react with C=N of the diisopfh and has a ring expansion. The successive pass would be thermal and with propanone elimination, as thermal rearrangement on phosphoric derivates described in the literature. In a second phase was studied, by Laser Flash Photolysis, the kinetic effect of the six aromatic derived of phosphoril-hidrazone (H, p-Cl, p-NO2, p-CN, p-NMe2 e p-CO2H) on the triplet excited state of four aromatic ketones: Xanthone, Tioxanthone, Benzophenone and Benzyl. The observed process to quencher, in all cases, was energy transference, because the rate constants are in the order of 1010M-1s-1. In this form was possible to estimate the energy of triplet excited state of these six phosphoril-hidrazone derivates. / O presente estudo divide-se em duas etapas bem distintas: Inicialmente, estudou-se a irradia??o de isatina na presen?a de diisopropil-dimetilfosforilidrazona (diisopfh) em clorof?rmio, a temperatura ambiente e comprimento de onda de 300nm. H? forma??o de um produto majorit?rio cujo peso molecular corresponde ? soma dos reagentes, diminu?do de 58g/mol. A estrutura deste produto foi elucidada por CG/EM, IV e RMN de 1H, 13C e 31P, al?m de t?cnicas como homocosy, hetycosy e outros. Prop?e-se um mecanismo via bi-radical formado a partir do estado excitado triplete da isatina com a liga??o C=N do composto diisopfh e conseq?ente expans?o do anel isat?nico; levando ? forma??o de um prov?vel produto fotoqu?mico prim?rio resultante de cicloadi??o. Numa segunda etapa, por processo t?rmico de elimina??o de propanona, similar a processo descrito na literatura por Olah, levaria a forma??o do fotoproduto detectado (derivado fosforil-benzodiazep?nico). Numa segunda etapa, estudou-se, por Fot?lise por Pulso de laser, o efeito cin?tico da presen?a de seis derivados arom?ticos de fosforilidrazona (H, p-Cl, p-NO2, p-CN, p-N (CH3)2 e p-CO2H) sobre o estado excitado triplete de quatro cetonas arom?ticas: tioxantona, xantona, benzofenona e benzil, todos em solu??o de acetonitrila. As constantes de velocidades obtidas (da ordem de difus?o da acetonitrila 1,9x1010 M-1s-1) indicam que o processo de supress?o de estado excitado se faz por transfer?ncia de energia. Desta forma foi poss?vel estimar a energia de estado excitado triplete destes derivados arom?ticos de fosforilidrazona.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-04T18:36:57Z No. of bitstreams: 1 2016 - CRISTINA SANTOS DA SILVA.pdf: 3106410 bytes, checksum: 18949ec17e0df834beb420705591824d (MD5) / Made available in DSpace on 2017-05-04T18:36:57Z (GMT). No. of bitstreams: 1 2016 - CRISTINA SANTOS DA SILVA.pdf: 3106410 bytes, checksum: 18949ec17e0df834beb420705591824d (MD5) Previous issue date: 2016-03-31 / CAPES / Chagas? Disease or American trypanosomiasis is an important parasitic disease in the Americas and is still considered one of the major neglected tropical diseases affecting millions of people worldwide due to lack of effective control. Thus, it has a significant impact on human health. This disease has its epidemiology conditioned by triatomines and mammals and its etiological agent is the protozoan Trypanosoma cruzi.Investigations on the adaptation mechanisms, gene regulation and parasite interaction vs. vector evolved, which proves the need for the use of molecular tools for the study and elucidation on adaptive changes in these parasites. Recently, it was found evidence where studies indicate that the expression of T. cruzi?s antioxidant enzymes such as cytosolic peroxiredoxin (TcCPx), mitochondrial peroxiredoxin (TcMPx), (TcAPX) and trypanothione synthetase (TXNI, TXNII), superoxide dismutase (SOD A and SOD B) can be part of parasite?s protective system and indicate factors related to different levels of virulence of the etiological agent.Thus, proteomics analysis and evaluation of the expression of antioxidant enzymes from different subcellular compartments can corroborate to the studies related to virulence indices and expression of proteins involved in this process. In this sense, the objectives of this study were to evaluate the morphology of the isolated samples SMM98, SMM36 and SMM1, analyze beyond the proteomic profile, the expression of antioxidant enzymes (TcCPx; TcMPx; TcAPx; TcTXNI; TcTXNII, SOD A and SOD B) and observe the redox status expression using isolates SMM36 and SMM98 in comparison with strains TCC, Silvio and DM28c. The results showed different morphology from the isolated, high levels of virulence, varied protein profile comparison between SMM98 isolated and SMM36, when treated with NAC and Heme changes were observed in the development of the parasites, indicating the participation of the Redox Status of the Rio de Janeiro used in this study. / A doen?a de Chagas ou tripanossom?ase americana ? uma importante doen?a parasit?ria nas Am?ricas e ainda hoje ? considerada uma das principais doen?as tropicais negligenciadas acometendo milh?es de pessoas no mundo devido ? falta de controle efetivo. Desta forma, apresenta um impacto significativo sobre a sa?de humana. Esta enfermidade tem sua epidemiologia condicionada pelos triatom?neos e os mam?feros e tem como agente etiol?gico o protozo?rio Trypanosoma cruzi.Investiga??es sobre os mecanismos de adapta??o, regula??o g?nica e intera??o parasito x vetor evolu?ram, o que comprova a necessidade da utiliza??o de ferramentas moleculares para o estudo e elucida??es sobre as mudan?as adaptativas ocorridas nestes parasitos. Recentemente evid?ncias surgiram neste sentido, onde estudos indicam que a express?o de enzimas antioxidantes do T. cruzi tais como: peroxirredoxinas citos?lica (TcCPx), mitocondriais (TcMPx), (TcAPX) e tripanotiona sintetase (TXNI, TXNII), super?xido dismutase (SOD A e SOD B) podem fazer parte do sistema protetivo do parasito e indicar fatores relacionados aos diferentes n?veis de virul?ncia deste agente etiol?gico. Desta forma, an?lises prote?mica e avalia??o da express?o de enzimas antioxidantes de diferentes compartimentos subcelulares podem corroborar para com os estudos relacionados aos ?ndices de virul?ncia e express?o de prote?nas envolvidas neste processo. Neste sentido, os objetivos deste trabalho foram avaliar a morfologia dos isolados das amostras SMM98, 36 e 1, analisar al?m do perfil prote?mico, a express?o de enzimas antioxidantes (TcCPx; TcMPx; TcAPx; TcTXNI; TcTXNII, SOD A e SOD B) e observar a express?o do status redox utilizando os isolados SMM36 e SMM98 em compara??o com as cepas TCC, Silvio e DM28c. Os resultados obtidos demonstraram aspectos morfol?gicos diferenciados dentre os isolados, n?veis de virul?ncia elevados, perfil de prote?nas variados quando comparados entre os isolados SMM98 e SMM36. E, quando tratados com Heme e NAC foram observadas altera??es no desenvolvimento dos parasitos, denotando a participa??o do Status Redox frente aos isolados do Rio de Janeiro utilizados neste estudo.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-09-28T14:16:27Z No. of bitstreams: 1 DIS_NATHAN_WILLIG_LIMA_COMPLETO.pdf: 3138188 bytes, checksum: 8747fa72c84172dbac724ce570075b26 (MD5) / Made available in DSpace on 2016-09-28T14:16:27Z (GMT). No. of bitstreams: 1 DIS_NATHAN_WILLIG_LIMA_COMPLETO.pdf: 3138188 bytes, checksum: 8747fa72c84172dbac724ce570075b26 (MD5) Previous issue date: 2016-08-08 / In this work, molecular dynamics simulations of thin organic films irradiated by fast heavy ions were implemented. In order to represent the ion energy deposition, it was used a Thermal Spike Model, in which the ion track is represented as a cylindrical region with high temperature. Two papers were submitted for publication based on this study. In the first paper, it was studied the impact of film thickness and the ion energy in the topological effects of radiation (such as crater diameter, crater depth and rim volume) and in the sputtering, comparing the results for a crystalline and amorphous solids modeled by the Lennard-Jones potential. In the second paper, the FENE potential was implemented to build samples with molecular chains. The ionic radiation effects were then compared between films with molecular chains (modeled by the FENE potential) and without molecular chains (using the Lennard-Jones potential). In both works, the effects of radiation were explained by analyzing the different mechanisms of energy dissipation: evaporation, melt flow and plastic deformation. Our results show that radiation effects are strongly determined by film thickness. The simulations with FENE potential show that the presence of molecular chains reduces significantly the effects of radiation. In solids thinner than the mean gyration radius of the sample, there was not any radiation effect, indicating that the effect reduction is related not only to the decreasing of mobility but also to molecular conformation and entanglement. / Nesse trabalho foram realizadas simula??es computacionais por din?mica molecular de filmes finos org?nicos irradiados por ?ons pesados e r?pidos. Para representar a deposi??o de energia pelo ?on foi utilizado o Modelo de Thermal Spike, atrav?s do qual a trilha i?nica ? representada como uma regi?o cil?ndrica de alta temperatura ao longo do material. Dois artigos foram submetidos para publica??o a partir desse estudo. No primeiro artigo, o impacto da espessura do filme e da energia do ?on incidente nos efeitos topol?gicos da radia??o (como di?metro da cratera, profundidade da cratera e volume da protuber?ncia) e do sputtering foram investigados, comparando-se os resultados de s?lidos cristalinos e amorfos modelados pelo potencial de Lennard-Jones. No segundo artigo, o potencial FENE foi implementado para construir amostras com cadeias moleculares. Os efeitos da radia??o i?nica foram ent?o comparados entre os filmes com cadeias moleculares (modelados pelo potencial FENE) e filmes sem cadeias moleculares (modelados com o potencial de Lennard-Jones). Em ambos os trabalhos, os efeitos da radia??o foram explicados verificando-se os diferentes mecanismos de dissipa??o de energia: evapora??o, melt flow e deforma??o pl?stica. Nossos resultados mostram que os efeitos da radia??o s?o fortemente impactados pela espessura do filme. As simula??es com o potencial FENE mostram que a presen?a de cadeias moleculares reduz significativamente todos os efeitos da radia??o. Para s?lidos mais finos que o raio de gira??o m?dio das mol?culas, nenhum efeito da radia??o foi observado, indicando que a redu??o dos efeitos est? relacionada n?o s? ? diminui??o de mobilidade, mas tamb?m ? conforma??o e emaranhamento molecular.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-10-17T15:38:20Z No. of bitstreams: 1 TES_MICHEL_WILLIAN_ZIMMERMANN_DE_ALMEIDA_COMPLETO.pdf: 4073596 bytes, checksum: 2865f2f2a8aea6e1016a829837542a0c (MD5) / Made available in DSpace on 2016-10-17T15:38:21Z (GMT). No. of bitstreams: 1 TES_MICHEL_WILLIAN_ZIMMERMANN_DE_ALMEIDA_COMPLETO.pdf: 4073596 bytes, checksum: 2865f2f2a8aea6e1016a829837542a0c (MD5) Previous issue date: 2016-08-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The thesis that follows, aimed at analyzing the Brazilian automobile industry between the 1970s and 1990s from the analysis of business development John Gurgel, Aldo Besson and Iltemar Gobbi and its companies, Gurgel Motores SA and Aldo Auto Covers, later renamed Besson , Gobbi SA the starting point was the realization that the automotive industry plays today a central role in the Brazilian economy. So, we tried to identify the strategies that have enabled the development of these two automobile companies of national nature, its growth ambitions and the way they related to multinationals, this industrial branch, installed here. High taxes that protected the Brazilian industry in the years 70/80, allowed the emergence of dozens of small manufacturers over the proposed period. However, the economic imbalance of the eighties, demanded immense creativity of these entrepreneurs, who started the 1990s with an economic opening that exposed their markets and companies for competition with imports. From this, we fix its technological developments and innovation capabilities as a central means for understanding their realities and potentials. Methodologically, this thesis was based on bibliographic analysis and primary documents, combined with several interviews with people involved in the issue, and others performed in various news programs. / A tese que segue, buscou analisar a ind?stria automobil?stica brasileira entre as d?cadas de 1970 e 1990 a partir da an?lise do desenvolvimento empresarial de Jo?o Gurgel, Aldo Besson e Iltemar Gobbi e suas empresas: Gurgel Motores S.A. e Aldo Auto Capas, renomeada posteriormente para Besson, Gobbi S.A. Para tanto, partimos da compreens?o de que a ind?stria automobil?stica desempenha ainda hoje papel central na economia brasileira. Assim, buscamos identificar as estrat?gias que permitiram o desenvolvimento destas duas empresas automobil?sticas de cunho nacional, suas ambi??es de crescimento e a forma com que se relacionavam com as multinacionais deste ramo industrial aqui instaladas. Os elevados impostos que protegiam a ind?stria brasileira, entre os anos 70/80, permitiram o surgimento de dezenas de pequenas montadoras ao longo do per?odo proposto, todavia, o desequil?brio econ?mico dos anos oitenta, exigia imensa criatividade destes empres?rios, que iniciaram a d?cada de 1990 com uma abertura econ?mica que exp?s seus mercados e empresas para a competi??o com os importados. Por esse meio, fixamos seus desenvolvimentos tecnol?gicos e capacidades de inova??o como meio central para a compreens?o de suas realidades e potencialidades. Metodologicamente, esta tese foi centrada em an?lises bibliogr?ficas e de documentos prim?rios, combinados com a realiza??o de diversas entrevistas com pessoas envolvidas ao tema e outras realizadas em programas jornal?sticos diversos.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-11-16T13:11:07Z No. of bitstreams: 1 DIS_ANA_PAULA_SZEZEPANIAK_GOULART_COMPLETO.pdf: 1331186 bytes, checksum: c62191ee8989facb5039525bce1735d3 (MD5) / Made available in DSpace on 2016-11-16T13:11:08Z (GMT). No. of bitstreams: 1 DIS_ANA_PAULA_SZEZEPANIAK_GOULART_COMPLETO.pdf: 1331186 bytes, checksum: c62191ee8989facb5039525bce1735d3 (MD5) Previous issue date: 2016-08-26 / Objective: To evaluate association between histological grade of low (CIN I) and high-grade intraepithelial cervical lesions (CIN II and III) and the immunohistochemical expression of p16INK4a, hTert and ki67 in order to establish the behavior of these lesions and recurrence during follow-up of two years. Patients and Methods: a historical cohort study of 94 women to analyze 3 groups of patients with low (CIN I) and high-grade (CIN II and III) cervical intraepithelial lesions underwent to knife, to determine the recurrence of disease associated to expression of immunohistochemical markers p16INK4a, Ki67 and hTERT. Results: Mean age of the patients was 38.2 years. Patients with CIN I, there was a lower p16INK4a expression, while in patients CIN II or I / II a higher frequency of p16INK4a ?10% was observed. In patients with CIN III there was a higher frequency of p16INK4a expression (> 50%). There were more patients with Ki67 ?10% of the cell population and lower frequency of Ki67 expression (> 50%) in CIN I. In CIN III there were fewer patients in the category Ki67 ?10% and CIN II and III group there were more patients with absent expression of Ki67. There wasn't association between hTert and histological grade. When comparing the markers between subjects with and without recurrence there was no statistically significant difference. Conclusion: There was a statistically significant association between p16INK4a, P16iNK4aM and Ki67 and histological grade, however there was no statistical difference in the expression of these markers in relation to recurrence of disease during the study period. / Objetivo: Avaliar a associa??o entre gradua??o histol?gica e a express?o imunoistoqu?mica para P16iNK4a, hTert e ki67, a fim de estabelecer o comportamento dessas les?es quanto ? recorr?ncia durante o seguimento de dois anos. Pacientes e M?todos: Estudo de coorte hist?rica incluindo 94 mulheres, em que foram analisados 3 grupos de pacientes com les?es intraepiteliais cervicais de baixo (NIC I) e alto grau , classificadas em NIC II e III, submetidas ? coniza??o, a fim de determinar a recorr?ncia da doen?a conforme a express?o dos marcadores imunoistoqu?micos P16iNK4a, Ki67 e hTert. Resultados: A idade m?dia das pacientes foi de 38,2 anos. Nas pacientes com NIC I, houve maior frequ?ncia de P16iNK4a ausente, nas pacientes NIC II ou I/II observou-se maior frequ?ncia com P16iNK4a ?10%. Nas pacientes NIC III observou-se maior frequ?ncia de express?o de P16iNK4a (>50%). Na categoria NIC I houve mais pacientes com Ki67 ?10% e menor frequ?ncia de Ki67 (>50%). Na categoria NIC III houve menos pacientes na categoria Ki67 ?10% e no grupo NIC II e III houve mais pacientes com Ki67 ausente. N?o houve associa??o entre a express?o do marcador imunoistoqu?mico hTert e gradua??o histol?gica. Quando comparadas as express?es dos marcadores entre sujeitos com e sem recorr?ncia, n?o houve diferen?as estatisticamente significativas. Conclus?o: Houve uma associa??o estatisticamente significativa entre P16iNK4a, P16iNK4aM e Ki67 e a gradua??o histol?gica, entretanto n?o houve diferen?a estat?stica na express?o desses marcadores em rela??o ? recorr?ncia da doen?a no per?odo avaliado.

Submitted by Salete Sartori (ssartori@pucrs.br) on 2017-01-16T13:46:11Z No. of bitstreams: 1 DIS_EMANUELLI_LOURENCO_CABRAL_COMPLETO.pdf: 2324920 bytes, checksum: cdf79816569d7d9b352a5a2d9b93437f (MD5) / Made available in DSpace on 2017-01-16T13:46:11Z (GMT). No. of bitstreams: 1 DIS_EMANUELLI_LOURENCO_CABRAL_COMPLETO.pdf: 2324920 bytes, checksum: cdf79816569d7d9b352a5a2d9b93437f (MD5) Previous issue date: 2016-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The use of biomaterials that can replace or restore damaged tissues in the human body is necessary to improve the quality and life expectancy of the population. In this sense, the present project aims the study and development of different membranes based on biostable polyurethane, the incorporation of rapamycin, an antithrombogenic drug that can help about the inhibition of blood vessel narrowing, and the evaluation to verify its potential application in vascular area. Therefore, the obtained membranes showed three different morphologies, a membrane with porous surface (average pore size 3,3 ?m ? 0,8 ?m) ? named porous PU ? other membrane with an irregular surface, but without porous ? dense PU ? and for the last, a membrane with internal interconnections ? leached PU. There were realized for each membrane the tests of wettability and contact angle. The leached PU showed higher average of body fluid absorption and porous PU showed higher hydrophilicity, however after the addition of rapamycin, dense PU showed more hydrophilicity. About calcification test, both of three membranes showed minerals deposition, but this did not happen with dense PU after incorporation of drug. The thermal characterizations of the membranes were according with literature for polyurethanes, as the mechanical behavior. Lastly, the membranes did not showed in vitro cytotoxicity, which means that they could be used within our bodies. Thus, the obtained membranes showed their interesting and high potential for use and improvement / O uso de biopol?meros que possam substituir ou restaurar tecidos danificados no corpo humano ? necess?rio para a melhoria na qualidade e expectativa de vida da popula??o. Neste sentido, o presente projeto visa o estudo e desenvolvimento de diferentes membranas baseadas em poliuretano bioest?vel, a incorpora??o da rapamicina, um f?rmaco antitrombog?nico que pode auxiliar na inibi??o do estreitamento dos vasos sangu?neos, e a avalia??o para verificar sua potencial aplica??o na ?rea vascular. Sendo assim, as membranas obtidas apresentaram tr?s morfologias distintas, uma membrana com superf?cie totalmente porosa (tamanho m?dio de poros de 3,3 ?m ? 0,8 ?m) ? denominada PU poroso ? outra com irregularidades em sua superf?cie, por?m sem poros ? PU denso ? e por fim, uma membrana com interconex?es internas ? PU lixiviado. Para cada membrana foram realizados ensaios como teste de inchamento e an?lise do ?ngulo de contato. O PU lixiviado apresentou maior m?dia de absor??o de fluido corp?reo e o PU poroso apresentou maior hidrofilicidade, contudo, ap?s a adi??o da rapamicina o PU denso mostrou-se mais hidrof?lico. Em rela??o ao teste de calcifica??o, as tr?s membranas apresentaram dep?sito de minerais, o que n?o ocorreu para o PU denso ap?s a adi??o do f?rmaco. As caracteriza??es t?rmicas das membranas mostraram-se de acordo com a literatura para poliuretanos, assim como o comportamento mec?nico. Por fim, os estudos de citotoxicidade mostraram que as membranas n?o s?o citot?xicas, podendo ser utilizadas dentro do nosso organismo. Dessa maneira, as membranas obtidas mostram-se interessantes e com grande potencial de uso e aperfei?oamento

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2017-03-10T17:30:42Z No. of bitstreams: 1 TES_CARLOS_JESUS_PEREIRA_HAYGERT_PARCIAL.pdf: 1035016 bytes, checksum: 2e1b1323cdbd59f0bc70829382bd1563 (MD5) / Made available in DSpace on 2017-03-10T17:30:42Z (GMT). No. of bitstreams: 1 TES_CARLOS_JESUS_PEREIRA_HAYGERT_PARCIAL.pdf: 1035016 bytes, checksum: 2e1b1323cdbd59f0bc70829382bd1563 (MD5) Previous issue date: 2016-07-12 / Objective: To compare the total radiation doses obtained in an optimized protocol tomography (MSCT) for hospital use (CTdBem), with the doses obtained in panoramic radiography for dental use, both in pediatric patients and to compare the actual radiation doses to lens, thyroid, salivary glands and gonads obtained from MSCT x panoramic radiograph. Methods: radiation dose data obtained were used in examinations of pediatric patients, and children under 18 years of age treated at the University Hospital of Santa Maria (HUSM), who needed dental evaluation by diagnostic imaging methods. The value of the estimated effective dose of radiation was obtained by computational calculations using the data CTDI (Computed Tomography Dose Index) and DLP (Dose Lenght Product) of MSCT and DAP values (Dose Area Product) for panoramic radiography equipment. The organs were: crystalline, thyroid, salivary glands and gonads, and compared the effective doses of radiation obtained for the different equipment. The radiographic examinations were performed using the pan in equipment X-ray Instrumentarium OP200, 57-85kV, 2-16mAs and acquisition time of approximately 11 seconds. For MSCT was used Toshiba Aquilion64 using 120kV, 10mAs but and acquisition time of approximately 6 seconds. Results: Comparison of DLP CTdBem protocol with panoramic radiograph showed dose values 28,48mSv and 36,45mSv respectively. Comparing the effective doses were found dose values for salivary gland 0,28mSv and 0,36mSv to gonads 2,28mSv and 2,92mSv for thyroid 0,28mSv and 0,36mSv and lens 3, 42mSv and 4,37mSv. Conclusion and Clinical Relevance: The authors conclude that the total doses and also the effective doses of radiation to lens, thyroid, salivary glands and gonads obtained in an optimized protocol of multislice computed tomography for hospital use (CTdBem) doses were lower based on panoramic radiographs. / Objetivo: Comparar as doses totais de radia??o obtidas em um protocolo otimizado de tomografia computadorizada multislice (TCMS) para uso hospitalar (CTdBem), com as doses obtidas em radiografia panor?mica de uso odontol?gico, ambos realizados em pacientes pedi?tricos e comparar as doses efetivas de radia??o para cristalino, tireoide, gl?ndulas salivares e g?nadas obtidas em TCMS x radiografia panor?mica. M?todos: Foram utilizados dados de dose de radia??o obtidos em exames de pacientes pedi?tricos e jovens de at? 18 anos de idade atendidos no Hospital Universit?rio de Santa Maria (HUSM), que necessitavam de avalia??o odontol?gica por m?todos de diagn?stico por imagem. O valor da estimativa da dose efetiva de radia??o foi obtido por calculo computacional utilizando os dados de CTDI (Computed Tomography Dose Index) e DLP (Dose Lenght Product) do TCMS e os valores de DAP (Dose Area Product) para o equipamento de radiografia panor?mica. Foram considerados os ?rg?os: cristalino, tireoide, gl?ndulas salivares e g?nadas, sendo comparadas as doses efetivas de radia??o obtidas para os diferentes equipamentos. Os exames radiogr?ficos foram realizados utilizando a panor?mica em equipamento de raios-X Instrumentarium OP200, 57-85kV, 2-16mAs e tempo de aquisi??o de aproximadamente 11 segundos. Para a TCMS foi utilizado o Toshiba Aquilion64 utilizando 120kV, 10mAs e tempo de aquisi??o de aproximadamente 6 segundos. Resultados: A compara??o da DLP do protocolo CTdBem com radiografia panor?mica mostrou valores de dose de 28,48mSv e 36,45mSv, respectivamente. Quando comparadas as doses efetivas foram encontrados os valores de dose para gl?ndulas salivares de 0,28mSv e 0,36mSv, para g?nadas de 2,28mSv e 2,92mSv, para tireoide de 0,28mSv e 0,36mSv e para cristalino de 3,42mSv e 4,37mSv. Conclus?o e Relev?ncia Cl?nica: Os autores concluem que as doses totais e tamb?m as doses efetivas de radia??o para cristalino, tireoide, gl?ndulas salivares e g?nadas obtidas em um protocolo otimizado de tomografia computadorizada multislice para uso hospitalar (CTdBem) foram inferiores as doses obtidas em radiografias panor?micas.

Made available in DSpace on 2015-04-14T14:51:29Z (GMT). No. of bitstreams: 1 451666.pdf: 1289575 bytes, checksum: 022edd4e2e930676c57fc69c0dc3e849 (MD5) Previous issue date: 2013-07-24 / Superparamagnetic iron oxide nanoparticles (SPIONs) are of great interest in nanomedicine due to their capability to act simultaneously as a contrast agent in magnetic resonance imaging and as a targeted drug delivery system with good biocompatibility. At present, one of the biggest concerns about the use of SPIONs remains around its toxicity. For this reason, it is important to establish the safe upper limit for each use. In the present study, SPION coated with cross-linked and aminated dextran (CLIO-NH2) were synthesized by the co-precipitation method and characterized by transmission electron microscopy (TEM) and light scattering dynamics. The analysis of the elementary composition of the solution at the end of the synthesis was also performed. The magnetite core size was 5.5 ? 1.4 nm, on a concentration of 10 mg Fe-NPs/ml. We have evaluated the effects of different CLIO-NH2 doses (20, 50, 100, 140 and 200 mg/kg) as a function of time after exposure (one, 16, 24 and 48 hours) on AChE activity and ache expression in zebrafish brain. At tested concentrations, only the animals exposed to 200 mg/kg, and assessed 24 h after administration of the nanoparticles, have shown decreased AChE activity. These values returned to control levels after 48 h of exposition, indicating a transitory toxical effect. The RT-qPCR results suggested that inhibition of brain AChE is not directly related with the transcriptional control, and it was probably due to post-transcriptional events. Once ACh is recognized to play an important role in the regulation of locomotor control, we further evaluated parameters of zebrafish swimming activity. CLIO-NH2 at 200mg/kg, evaluated after 24 h, also impaired all the tested parameters of zebrafish swimming activity, i.e. decreased traveled distance, mean speed, number of line crossings, and turn angle. We further investigated the iron accumulation in zebrafish brain by ICP-MS, and a significant higher level of ferric iron was found in zebrafish brains exposed to CLIO-NH2. In summary, the results presented herein provide further experimental evidence that exposure to high doses of dextran-coated iron oxide nanoparticles can be transiently neurotoxic. / Nanopart?culas superparamagn?ticas de ?xido de ferro (SPIONs) s?o de grande interesse na nanomedicina, devido ? sua capacidade para agir, simultaneamente, como um agente de contraste em imagem por resson?ncia magn?tica e como um sistema de entrega de f?rmacos espec?ficos, possuindo boa biocompatibilidade. Atualmente, uma das maiores preocupa??es com a utiliza??o de SPIONs permanece em torno da sua toxicidade e, por esta raz?o, ? importante estabelecer um limite de seguran?a para sua utiliza??o. Neste estudo, SPIONs revestidas com dextran-aminado (CLIO-NH2) foram sintetizados pelo m?todo de co-precipita??o e caracterizadas por microscopia eletr?nica de transmiss?o (MET) e din?mica de espalhamento de luz. A an?lise da composi??o elementar da solu??o no final da s?ntese foi tamb?m realizada. O tamanho do n?cleo de magnetite foi de 5,5 ? 1,4 nm, com uma concentra??o de 10 mg Fe-NPs/ml. Foram avaliados o efeito de diferentes doses de CLIO-NH2 (20, 50, 100, 140 e 200 mg/kg), ap?s a exposi??o de CLIO-NH2 (em uma, 16, 24 e 48 h), sobre a atividade de AChE e sobre a express?o de ache em c?rebro de peixe-zebra. Nas concentra??es testadas, apenas os animais expostos a 200 mg/kg, testados 24 h ap?s a administra??o das nanopart?culas, demonstraram diminui??o da atividade da AChE. Quarenta e oito horas ap?s exposi??o a CLIO-NH2 os valores voltaram aos n?veis controle, indicando um efeito t?xico transit?rio. Os resultados de RT-qPCR sugerem que a inibi??o da AChE no c?rebro n?o est? diretamente relacionada com o controle da transcri??o e que esta relacionada com a modula??o de eventos p?s-transcricionais. Uma vez que a ACh ? reconhecida por desempenhar um papel importante na regula??o do controle locomotor, foram avaliados par?metros da atividade da nata??o do peixe-zebra. CLIO-NH2, ? 200 mg/kg, ap?s 24 h de tratamento, tamb?m prejudicou todos os par?metros testados de comportamento de nado, ocorrendo diminui??o da dist?ncia percorrida, velocidade, n?mero de cruzamentos de linha e ?ngulo de virada. Ainda foi analisado o ac?mulo de ferro no c?rebro de peixe-zebra, por ICP-MS, onde um n?vel significativamente maior de ferro f?rrico foi encontrado nos c?rebros de peixe-zebra expostos a CLIO-NH2 nas mesmas condi??es experimentais (200 mg/kg e 24 h de exposi??o). Concluindo, os resultados apresentados fornecem evid?ncias de que doses elevadas de nanopart?culas de ?xido de ferro, revestidas com dextran-aminado, podem produzir neurotoxicidade transit?ria, coincidente com n?veis cerebrais elevados de ferro, bem como as altera??es comportamentais.

Made available in DSpace on 2015-04-14T14:51:31Z (GMT). No. of bitstreams: 1 456553.pdf: 3406463 bytes, checksum: 401e17a9aecc3c36095588e483dd1282 (MD5) Previous issue date: 2014-03-12 / The causative agent of tuberculosis (TB), Mycobacterium tuberculosis, infects one-third of the world population. The World Health Organization estimates that 8.6 million new TB cases occurred in 2012, resulting in 1.3 million deaths worldwide. Thus, there is a continuous need to find promising molecular targets for the development of anti-TB agents and to identify pathogenic determinants associated with M. tuberculosis virulence aiming the development of attenuated mutant strains as new vaccine candidates against TB. Enzymes involved in purine and pyrimidine biosynthesis have important roles in cellular metabolism, as they provide nucleotides that are essential components of a number of essential biomolecules. Cytidine deaminase (CDA) catalyzes the hydrolytic deamination of cytidine to uridine, and belongs to the pyrimidine salvage pathway. The CDA from M. tuberculosis (MtCDA) is a target for the development of attenuated strains of M. tuberculosis because it may be involved in mechanisms of pathogenicity such as latency. This work presents the crystal structures of MtCDA in complex with uridine (2.4 ? resolution) and deoxyuridine (1.9 ? resolution). Molecular dynamics (MD) simulation was performed to analyze the physically relevant motions involved in the protein ligand recognition process, showing that structural flexibility of some residues are important to product binding. In addition, MD simulations allowed the analysis of the stability of tetrameric MtCDA structure. The role of the conserved glutamate-47 (E47) residue was evaluated by construction of five mutant proteins (E47A, E47D, E47L, E47H, and E47Q). Mutants E47A and E47H were expressed in insoluble fraction, whereas E47D, E47L and E47Q were soluble and purified by HPLC. The E47D, E47L and E47Q mutants contained 1 mol of Zn2+ per mol of protein subunit. These mutations had no effect on oligomerization state of MtCDA. Steady-state kinetic results showed that KM values for the E47D and E47Q mutants were not significantly altered, whereas there was a decrease in kcat values of 37-fold for E47D and 19-fold for E47Q mutant. No activity could be detected for E47L mutant. The crystal structure of the E47D mutant was solved by X-rays diffraction, using synchrotron light. An essential role was proposed for the ?-carboxyl group of E47, and its involvement in the catalityc process. On the other hand, an important part of drug and vaccine development is the identification of gene products that are critical for bacterial growth and survival. In this way the knockout of the cdd gene was performed in order to evaluate the importance of the cdd gene for mycobacteria growth in vitro and in vivo. Our results suggest that cdd gene is not an essential gene for in vitro growth under the employed experimental conditions. Infection in mice with the knockout strain of cdd gene has shown a significant reduction in the CFU s in lungs and spleen of the infected animals. Futher experiments are under way to confirm such findings. Finally, results from enzymatic characterization, site directed mutagenesis and gene replacement may be the starting point for a better understanding about the role of cytidine deaminase in M. tuberculosis metabolism and open up the possibility for a rational design of attenuated strain, that may be useful for future development of a new vaccine candidate against human TB. / O agente causador da tuberculose (TB), Mycobacterium tuberculosis, infecta um ter?o da popula??o mundial. A Organiza??o Mundial da Sa?de estima que 8,6 milh?es de novos casos de tuberculose ocorreram em 2012, resultando em 1,3 milh?es de mortes no mundo. Assim, existe uma necessidade cont?nua de encontrar alvos moleculares promissores para o desenvolvimento de agentes anti-tuberculose e identificar determinantes de virul?ncia associados com a patog?nese de M. tuberculosis, visando a obten??o de cepas mutantes atenuadas como candidatas a novas vacinas contra a tuberculose. As enzimas envolvidas na bios?ntese de purina e pirimidina t?m pap?is importantes no metabolismo celular, uma vez que proporcionam nucle?tidos, os quais s?o componentes essenciais de um grande n?mero de biomol?culas. A enzima Citidina deaminase (CDA) catalisa a desamina??o hidrol?tica da citidina a uridina, e faz parte da via de salvamento das pirimidinas. A CDA de M. tuberculosis (MtCDA) devido a sua n?o essencialidade pode ser um alvo interesante para a obten??o de cepas atenuadas para o desenvolvimento de vacinas auxotr?ficas contra a tuberculose, j? que pode estar envolvido nos mecanismos de invas?o e lat?ncia. No presente trabalho s?o apresentadas as estruturas cristalogr?ficas da MtCDA em complexo com uridina (2,4 ? de resolu??o) e deoxiuridina (1,9 ? de resolu??o). Simula??o da Din?mica Molecular (MD) foi realizada com o prop?sito de analisar os movimentos fisicamente relevantes envolvidos no processo do reconhecimento prote?na-ligante, e mostra que a flexibilidade estrutural de algumas regi?es da prote?na s?o importantes para a liga??o do produto. Al?m disso, simula??es MD permitiram a an?lise da estabilidade da estrutura tetram?rica da MtCDA. O papel do res?duo conservado glutamato 47 (E47) foi avaliado mediante a constru??o de cinco prote?nas mutantes (E47A, E47D, E47L, E47H, e E47Q). Os mutantes E47A e E47H foram expressos na fra??o insol?vel, enquanto E47D, E47L e E47Q foram expressas na fra??o sol?vel e purificadas por cromatografia l?quida de alta performance (HPLC). Os mutantes E47D, E47L e E47Q continham 1 mol de Zn2+ por mol de subunidade de prote?na. Estas muta??es n?o tiveram efeito sobre o estado de oligomeriza??o da MtCDA. Resultados cin?ticos em estado estacion?rio mostraram que os valores de KM para os mutantes E47D e E47Q n?o foram alterados significativamente, enquanto houve uma redu??o nos valores de kcat de 37 vezes para E47D e 19 vezes para a mutante E47Q. N?o foi detectada qualquer atividade para a mutante E47L. A estrutura cristalogr?fica do mutante E47D foi resolvida por cristalografia de raios-X o que nos permitiu propor um papel catal?tico para o grupo ?-carboxila do residuo E47, sugerindo o envolvimento de um pr?ton na cat?lise. Por outro lado, uma parte essencial para o desenvolvimento de novos f?rmacos e vacinas, ? a identifica??o de produtos de genes que s?o fundamentais para o crescimento e a sobreviv?ncia bacteriana in vitro e in vivo. Desta forma, foi realizado o nocaute do gene cdd a fim de avaliar a import?ncia deste gene para o crescimento do bacilo em vida livre e em condi??es de estresse (vida intracelular). Nossos resultados sugerem que o gene cdd n?o ? um gene essencial para o crescimento do bacilo in vitro sob as condi??es experimentais utilizadas. Experimentos de infec??o em camundongos com a cepa nocaute do gene cdd mostraram uma significativa redu??o nas UFC s determinadas no pulm?o e ba?o dos animais infectados. Con tudo, experimentos de crescimento in vitro e infec??o em camundongos est?o sendo realizados a fim de confirmar os resultados obtidos. Os resultados da caracteriza??o enzim?tica e substitui??o g?nica s?o o ponto de partida para o melhor entendimento sobre o papel da enzima no metabolismo de nucleot?deos em M. tuberculosis, al?m de abrirem a possibilidade para o desenho racional de uma cepa atenuada, ?til para o futuro desenvolvimento de uma nova candidata a vacina contra a tuberculose humana

Submitted by PPG Medicina e Ci?ncias da Sa?de (medicina-pg@pucrs.br) on 2018-10-24T17:02:58Z No. of bitstreams: 1 JULIANA_LORENZONI_ALTHOFF.pdf: 23099056 bytes, checksum: 2ebbb4db3683a55ddc1d12778cf36c64 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-10-25T14:52:43Z (GMT) No. of bitstreams: 1 JULIANA_LORENZONI_ALTHOFF.pdf: 23099056 bytes, checksum: 2ebbb4db3683a55ddc1d12778cf36c64 (MD5) / Made available in DSpace on 2018-10-25T15:03:03Z (GMT). No. of bitstreams: 1 JULIANA_LORENZONI_ALTHOFF.pdf: 23099056 bytes, checksum: 2ebbb4db3683a55ddc1d12778cf36c64 (MD5) Previous issue date: 2009-03-23 / Background: The colon-rectal cancer is the third most frequent neoplasia in the western world with the highest mortality rates. The progression of normal colon tissue to invasiveness neoplasia is follow by several processes called carcinogenesis. Afterwards it converges to the cellular migration and metastasis of the tissue. The metabolic ways of the E26 (Ets) transcription factors, identified in a great variety of species, contributes in this process, by activating or repressing the DNA transcription. Specially, the prostate-derived Ets factor (PDEF) which prognosis and cancer colon-rectal relation action is not completely elucidating at the moment. Methods: A retrospective cohort of patients with pathologic stage I ? III colon-rectal cancer, diagnosed and treated in the same institution between 2002 and 2008, was study. Histological and clinical features as well as clinical outcomes and survival were reviewed. The tissue microarrays (TMA), immunohistochemical analysis and image capture quantification were carried out in representative blocks of tumor with antibodies for the detection of the PDEF expression and Ki-67. The endpoints were to determine the prevalence of the PDEF protein expression and its correlation with these population?s prognostic factors. Results: The sample was constituted 46 patients and the median follow-up was 23,2 months. There was a trend towards loss of PDEF protein expression according to the patients? clinical stage. PDEF expression values were 30,3%, 25,8% and 14,7% in stages I, II and III, respectively. There was not a significant correlation with the lost of PDEF protein expression and the clinical and pathological characteristics along with the proportion of Ki-67 proliferative marker and the patient?s global survival. Conclusions: These results suggest that the PDEF protein, member of the Ets family, act as a repression gene of cancer colon-rectal carcinogenesis. The PDEF expression analysis can be an interesting prognostic marker and a therapeutic target. New studies with more patients and a long follow-up are necessary to validate these results. / Base te?rica: O c?ncer colorretal ? a terceira neoplasia mais freq?ente no mundo ocidental com taxas de mortalidade ainda consideras altas. A progress?o do tecido epitelial do c?lon normal at? o est?gio de neoplasia invasiva ? acompanhada de uma s?rie de processos celulares chamados carcinog?nese que, ao fim, convergem para o potencial de migra??o celular e metastatiza??o. As vias metab?licas da fam?lia dos genes Ets (E26 - sequ?ncia espec?fica de transcri??o), identificada em uma grande diversidade de esp?cies, contribuem neste processo, ativando ou reprimindo transcri??es de DNA. Em especial o fator derivado prost?tico (PDEF) cujo progn?stico e mecanismo de a??o relacionado ao c?ncer colorretal, at? o momento, n?o est? claramente elucidado. M?todos: Uma coorte retrospectiva de pacientes com carcinoma colorretal est?gios de I a III, diagnosticados e tratados na mesma institui??o de 2002 a 2008, foi estudada. As caracter?sticas histol?gicas e cl?nicas, bem como os dados de evolu??o e a sobrevida foram revisados. A an?lise de imunoistoqu?mica com m?todo de matriz de amostras teciduais (TMA) e a quantifica??o por captura de imagem foram realizadas em blocos representativos do tumor com anticorpos para detec??o da express?o da prote?na PDEF e Ki-67. Os objetivos eram detectar a preval?ncia da express?o da prote?na PDEF e sua correla??o com fatores progn?sticos nesta popula??o. Resultados: A amostra foi constitu?da de 46 pacientes e tempo de seguimento mediano de 23,2 meses. Houve tend?ncia a perda da prote?na PDEF conforme o estadiamento dos pacientes sendo a express?o de 30,3%, 25,8% e 14,7% nos est?gio I, II e III, respectivamente, P=0,416. N?o encontrou-se associa??o significativa entre os achados cl?nico-patol?gicos, a dosagem do marcador de prolifera??o celular Ki-67 e a sobrevida global dos pacientes com a perda da express?o da prote?na PDEF. Conclus?es: Os resultados sugerem que a prote?na PDEF, membro da fam?lia Ets, atue como gene repressor da carcinog?nese do c?ncer colorretal. A an?lise de sua express?o pode se tornar um interessante marcador progn?stico e alvo terap?utico. S?o necess?rios novos estudos com amostras maiores e tempo de seguimento mais longo a fim de validar estes achados.