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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.
121

DNA methylation in paediatric germ cell tumours

Mohamed Noor, Dzul Azri January 2013 (has links)
Germ cell tumours (GeTs)affect both paediatric and adult populations, and can occur either in gonadal or extragonadal regions along the body's ventral midline. These tumours can be broadly categorized into two subgroups, seminomatous (SEM) or nonseminomatous (N-SEM). The latter can be further subcategorized into embryonal carcinoma (EC), teratoma, yolk sac tumour (YST) and choriocarcinoma (eC) according to their differentiation. As in many other tumours, DNA methylation has been proposed to be involved in GCTdevelopment. However to date, most studies were performed using adult testicular GCTs. Furthermore, these studies only include a handful of genes in their analysis. Thus, the roles of DNA methylation in paediatric and extragonadal GeTs have not been explored. Therefore, this project attempted to fill this gap in knowledge by performing methylation analysis in a cohort of paediatric GCT samples and GCTcell lines. Although paediatric GCTsmostly consist of teratomas, seminomas or YSTs, only the latter two were included in the methylation analysis as they were the only samples in the available tumour bank. Using the methylation level of L1NE-l repeat elements as a measurement of global genome methylation, we found that both paediatric seminoma and YST samples displayed global hypomethylation as compared to somatic controls. However, when methylation at gene promoter regions was investigated using Illumina Golden Gate methylation arrays, seminoma and YST exhibited very different methylation features. YSTs were found to be highly methylated at many of the sites investigated. Surprlslnglv, we found that the methylation features in seminoma were similar to the somatic controls. From this analysis, we identified 85 genes that were differentially methylated in the VSTs. However, by correlating our methylation data with the expression array data performed by our collaborators on the same samples, only eight of these genes (PYCARO, CASPB, C02, HOAC9, TFAP2C, ETV1, EV/2A, HLA-F) were differentially expressed. As in previous GCTstudies, our analysis was focused on the methylation at epG islands. During the course of this project technological advancement led to the creation of new methylation arrays that offer wider genome coverage. One example is the Infinium Methylation 450K array that covers more than 450,000 CpG sites and includes regions flanking the CpG islands such as the CpG shores and CpG shelves. Since no previous GCT studies have attempted to investigate methylation in those regions, we utilized this methylation array on four GCTcell lines; TCAM2 (seminoma), NT2Dl (teratocarcinoma), GCT27 (embryonal carcinoma) and GCT44 (yolk sactumour). Similar to previous GCT studies, we found that nonseminomatous GCT cell lines displayed higher methylation at the CpG islands as compared to the seminoma cell lines. Strikingly, expanding our analysis to other regions (CpG shores and shelves etc.) revealed that each GCT subtype exhibited distinct methylation features. Both ECand teratoma cell lines displayed higher methylation than the seminoma and YST cell lines at all regions. Interestingly, the YST cell line only showed higher methylation than the seminoma cell line at the CpG islands and to a lesser extent at the CpG shores while the seminoma cell line exhibited higher methylation at the CpG shelves as compared to the YST cell line. This is the first time such features have been reported for GCTs. From this Infinium methylation data, we have also identified a high number of hypermethylated genes including those that are uniquely methylated for each cell line. By correlating this methylation data with Affymetrix gene expression data, 98 genes that were differentially methylated and differentially expressed in the YST cell line have been identified. However, further analysis needs to be performed to understand the role of these genes in YST development. As in other types of tumour, the hypermethylation observed in the YST cell line might be caused by many epigenetic modifiers. Using real-time RT-PCR on three epigenetic modifiers (DNMT38, EZH2, SUZ12), we found that DNMT38 was highly expressed in the YST samples and cell line as compared to the seminoma samples and cell line. This suggests that DNMT38 might contribute to YST hypermethylation and resulting differences in their biology. However, knockdown of DNA methyltransferases (DNMTs) and DNMT38 using 5-azadeoxycytidine and microRNA-29b respectively, did not seem to have any effect on the response of all four GCT cell lines towards cisplatin. On the other hand, both knockdowns only caused little effect on cell migration; affecting only the seminoma and YST cell lines. Nonetheless, further analysis is still needed to fully assess the role of DNA methylation in regulating cell behaviour. In summary, paediatric YSTs displayed hypermethylation at many promoter regions as compared to seminomas. Meanwhile, methylation analysis at regions outside of CpG islands in GCTcell lines revealed unique methylation features for each GCT subtype which might indicate different underlying mechanisms in their development. Further analysis on genes found to be differentially methylated and differentially expressed in both paediatric and GCTcell lines are now needed to fully establish their role in GCT development.
122

Desenvolvimento de filtro cartucho de poliimida para altas temperaturas com resina ep?xi DGEBA e novo agente de cura

Ceron, Luciano Peske 27 March 2012 (has links)
Made available in DSpace on 2015-04-14T13:58:48Z (GMT). No. of bitstreams: 1 438589.pdf: 4872260 bytes, checksum: 7a7d4afb2e3e9cf2c377c01b09f71361 (MD5) Previous issue date: 2012-03-27 / This study evaluated the development of polyimide filter cartridge for use in high temperature particulate filtration of LDPE in the petrochemical industry. An epoxy prepared with DGEBA resin and a new curing agent formulation of polyaminoamide:amine 9:1 was evaluated for gluing pleating non-woven fabric to the cartridge metal borders. The research first step was to characterize LDPE particles (screening and SEM) of polyimide fiber (TGA and FTIR), polyimide non-woven fabric, polyester, and polyacrylonitrile copolymer (SEM) and epoxy (TGA, FTIR and DSC). The study second step was application in non-woven fabric for its dimensional alteration dimensional, permeability and inflammability. Polyamide non-woven fabric mechanical properties was analyzed by tensile strength under several temperatures in relation to time. Multifactor experiments for non-woven fabric filtration were analyzed using ANOVA. The third step was attributed to choosing an ideal formulation between DGEBA resin and curing agent through tensile strength test: regarding its preparation conditions, compared to other curing agents, thermal tests and humidity absorbance. Epoxy impact resistance was analyzed by izod. The last step was dedicated to cartridge filtration tests, laboratorial and industrial, in order to verify the construction set efficacy. Laboratory results obtained with cartridge prototypes show a better filtration performance with polyimide compared to other non-woven fabrics due its rapid onset of filtration cake, smaller load loss and low emission. After twenty-five months of industrial use of the polyimide cartridge filter with epoxy resin, it was observed good filtration conditions under up to 240?C with low particle emission, controlled load loss and power reuse in the industrial process. / Neste estudo avaliou-se o desenvolvimento de filtro cartucho de poliimida para uso em altas temperaturas, para filtra??o de particulados de PEBD em ind?stria petroqu?mica. Foi pesquisado um ep?xi, preparado com resina DGEBA e nova formula??o de agente de cura de poliaminoamida:amina 9:1, para a colagem do n?o tecido plissado nas extremidades met?licas do cartucho. A primeira etapa da pesquisa consistiu na caracteriza??o dos particulados de PEBD (peneiramento e MEV), da fibra de poliimida (TGA e FTIR), dos n?o tecidos de poliimida, do poli?ster e poliacrilonitrila copol?mero (MEV) e do ep?xi (TGA, FTIR e DSC). A segunda parte do estudo foi de desempenho em n?o tecidos, quanto ? altera??o dimensional, permeabilidade e inflamabilidade. Avaliou-se por tra??o as propriedades mec?nicas do n?o tecido de poliimida, submetido a diversas temperaturas em fun??o do tempo. Por meio da ANOVA realizou-se a an?lise dos experimentos multifatoriais de simula??o de filtra??o em n?o tecidos. A terceira parte envolveu a escolha da formula??o ideal entre resina DGEBA e agente de cura, atrav?s de ensaios de tra??o: quanto ?s condi??es de preparo, comparativos com outros agentes de curas, ensaios t?rmicos e absor??o de umidade. A resist?ncia ao impacto do ep?xi foi avaliada por izod. A ?ltima etapa foi dedicada aos testes de filtra??o em cartucho, laboratorial e industrial, para verificar a efic?cia do conjunto da constru??o. Os resultados laboratoriais obtidos com prot?tipos de cartuchos demonstraram a melhor performance de filtra??o com poliimida comparada aos outros n?o tecido, devido a r?pida forma??o da torta de filtra??o, pouca perda de carga e baixa emiss?o. Ap?s vinte e cinco meses de aplica??o industrial do filtro cartucho de poliimida com resina ep?xi, constatou-se boas condi??es de filtra??o at? 240?C, com baixa emiss?o de particulados, perda de carga controlada e reaproveitamento de energia no processo industrial.
123

Interrogativas-qu : um estudo introdut?rio comparativo a partir da hip?tese da sintaxe mais simples

Pereira, Andr? da Luz 20 January 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-05-16T17:06:24Z No. of bitstreams: 1 DIS_ANDRE_DA_LUZ_PEREIRA_COMPLETO.pdf: 705105 bytes, checksum: f0e5dcb2aeafdd39832d8260d516c466 (MD5) / Made available in DSpace on 2017-05-16T17:06:24Z (GMT). No. of bitstreams: 1 DIS_ANDRE_DA_LUZ_PEREIRA_COMPLETO.pdf: 705105 bytes, checksum: f0e5dcb2aeafdd39832d8260d516c466 (MD5) Previous issue date: 2017-01-20 / The aim of this work is to compare syntactic approaches to wh-questions, which is based on the generative perspective developed in linguistic studies from the 1950s onwards (CHOMSKY, 1957, 1965, 1972, 1977a, 1981, 1986, 1995). The central point of the comparison is relevance of the notion of movement for the syntactic studies of wh-questions. The mainstream of generative grammar uses the notion of movement to explain syntactic phenomena, and the Simpler Syntax Hypothesis believes that this notion is unnecessary, since there would be a simpler explanation (CULICOVER; JACKENDOFF, 2005, 2006). Specifically, the explanations about the construction of wh-question structures will be compared by the Simpler Syntax Hypothesis, which presents the alternative concepts to the concept of movement to describe the phenomenon of wh-questions, such as indirect licensing and discontinuous dependencies. The idea of movement is an important axis in the mainstream generative theory, since it evolves from the theory of traces, presented in the 1970s, but which gains strength and consolidates itself as movement theory especially from the Principles and Parameters (PP) program in the 1980s. Although words such as displacement and movement have already been mentioned in the course of the generative enterprise, they are consolidated in the PP program and remain in the Minimalist Program (PM), the next stage of the generative enterprise begun in the 1990s. Another aspect identified in the development of the research was the parallel architecture of the language structure proposed by the Simpler Syntax, which challenges the central role of syntax in linguistic studies, sharing with semantics and phonology the responsibility for generating structures from Conceptual Structure. To achieve the proposed objectives, a hypothetical-deductive model was used, in which the premises proposed by the theoretical lines under study are considered. The examples and sentences analyzed were not generated in situations of use by speakers. They were extracted from the theoretical sources analyzed or generated by the author. / Tendo por base a perspectiva gerativista, que se desenvolve nos estudos lingu?sticos a partir da d?cada de 1950 (CHOMSKY, 1957, 1965, 1972, 1977a, 1981, 1986, 1995), este trabalho tem por objetivo comparar abordagens sint?ticas sobre interrogativas-QU (em ingl?s, whquestions). O ponto central da compara??o ? relev?ncia da no??o de movimento para os estudos sint?ticos de interrogativas-QU. A Tradi??o da Gram?tica Gerativa se utiliza da no??o de movimento para explicar os fen?menos sint?ticos, e a Hip?tese da Sintaxe mais Simples acredita que esta no??o seja desnecess?ria, j? que haveria uma explica??o mais simples (CULICOVER; JACKENDOFF, 2005, 2006). Especificamente, ser?o comparadas as explica??es sobre a constru??o de estruturas interrogativas-QU pela hip?tese da Sintaxe mais Simples, que apresenta os conceitos alternativos ao conceito de movimento para descrever o fen?meno das interrogativas-QU, como licenciamento indireto e depend?ncias descont?nuas. A ideia de movimento ? um eixo importante na tradi??o da teoria gerativista, pois evolui a partir da teoria dos vest?gios, apresentada na d?cada de 1970, mas que ganha for?a e se consolida como teoria do movimento especialmente a partir do programa de Princ?pios e Par?metros (PP), na d?cada de 1980. Embora palavras como deslocamento e movimento j? tenha sido mencionadas anteriormente no percurso do empreendimento gerativista, elas se consolidam no PPP e se mant?m no Programa Minimalista (PM), etapa seguinte do empreendimento gerativista, iniciado na d?cada de 1990. Outro aspecto identificado no desenvolver da pesquisa foi a arquitetura paralela da estrutura da linguagem proposta pela Sintaxe mais Simples, que contesta o papel central da sintaxe nos estudos lingu?sticos, compartilhando com a sem?ntica e com a fonologia, a responsabilidade por gerar estruturas a partir do conceito de Estrutura Conceitual. Para atingir os objetivos propostos, foi utilizado um modelo hipot?tico-dedutivo, em que s?o consideradas as premissas propostas pelas linhas te?ricas em estudo. Os exemplos e senten?as analisadas n?o foram gerados em situa??es de uso por falantes. Foram extra?dos das fontes te?ricas analisadas ou geradas pelo autor.
124

The theme of exile in the "Li Sao" : a comparative view.

January 1984 (has links)
by George Jor Chi-keung. / Bibliography: leaves 124-152 / Thesis (M.Ph.) -- Chinese University of Hong Kong, 1984
125

Formula??o de um cold kit otimizada para marca??o 99m Tc para diagn?stico de tumor neuroend?crino

Fernandes, Bruna 26 March 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-06-18T13:18:31Z No. of bitstreams: 1 470631 - Texto Parcial.pdf: 431429 bytes, checksum: b5055842a739822ab3818d061be0160a (MD5) / Made available in DSpace on 2015-06-18T13:18:31Z (GMT). No. of bitstreams: 1 470631 - Texto Parcial.pdf: 431429 bytes, checksum: b5055842a739822ab3818d061be0160a (MD5) Previous issue date: 2015-03-26 / Several companies wordwide produce kits with 99mTc labelling for diagnosing neuroendocrine tumors. Aiming at producing this kind of product in Brazil, a formulation was proposed, based on the methodology developed by Guggenberg et ul, using HYNIC-TOC, SnCl2, EDDA, tricine, mannitol and ascorbic acid. For labelling the cold kit, metastable radionuclide technetium (99mTc), produced by a 99Mo generator was used. The product was stored at temperatures of 0 to 8?C and at 25?C before labelling. After the product was labelled, it was kept at room temperature for up to 4 hours. The time of exposure was sufficient to observe the shelf life of the product for each storage method. Considering a radiochemical purity (RCP) of 80%, the product remained stable during the eight-month storage at 0 to 8?C before labelling and up to 4 hours after labelling. Therefore, the use of this product is possible in centers of nuclear medicine for a longer period during the day. / No mundo, diversas empresas produzem kits para diagn?stico de tumores neuroend?crinos para marca??o com 99m Tc. Com a inten??o de nacionalizar esse tipo de produto no Brasil, uma formula??o foi proposta e baseada na metodologia desenvolvida por Guggemberg et al, utilizando HYNIC-TOC, SnCL2, EDDA, tricina, manitol e ?cido asc?rbico. Para marca??o do cold kit, foi utilizado o radionucl?deo tecn?cio metaest?vel(99m Tc), produzido por um gerador de 99Mo. O produto foi armazenado em temperaturasde 0 a 8?C e a 25?C antes da marca??o. Ap?s marca??o do produto, esse foi mantido em temperatura ambiente por at? quatro horas. O tempo de exposi??o foi suficiente para observar a vida do produto em cada m?todo de armazenamento. Considerando-se em limite de PRQ (pureza radioqu?mica) de 80%, o produto se mostrou est?vel durante os oito meses, quando armazenado entre 0 a 8?C antes da marca??o, e at? quatro horas p?s-marca??o. Sendo assim, poss?vel a utiliza??o desse produto, em centro de medicina nuclear, por per?odo mais longo durante o dia.
126

Adesivos termofund?veis : correla??o da natureza qu?mica com suas propriedades adesiva, reol?gica e t?rmica

Freitas, Renata Fialho Rocha 26 January 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-04-19T18:16:02Z No. of bitstreams: 1 TES_RENATA_FIALHO_ROCHA_FREITAS_COMPLETO.pdf: 4806428 bytes, checksum: f71ed86d06bc8b3f5e87e854cbe802c8 (MD5) / Made available in DSpace on 2016-04-19T18:16:02Z (GMT). No. of bitstreams: 1 TES_RENATA_FIALHO_ROCHA_FREITAS_COMPLETO.pdf: 4806428 bytes, checksum: f71ed86d06bc8b3f5e87e854cbe802c8 (MD5) Previous issue date: 2016-01-26 / Hot melt adhesives have the advantage that doesn?t liberate volatile organic compounds as solvent borne adhesives, and the consumption of these adhesives is growing up. The application of these adhesives covers various areas as packages, shoes, furniture and others. Thus, this study aims to evaluate the hot melt adhesion and interaction of different chemical natures (polyamide, polyurethane, EVA, HMPSA basis of rubber and polyolefin) with different substrates (TPU, PVC, TR, synthetic leather and leather). To evaluate the interaction between adhesive-substrate and to characterize adhesives and substrates were used the techniques: rheology, contact angle, FTIR, DRX, roughness analysis, NMR-1H, SEM, AFM, DSC, GPC and DMTA. Through determining the surface energy and the dispersive and polar components of adhesives and substrates by contact angle, it was possible to calculate work of adhesion and compare with the bonding performance. From this, it was observed that polyurethane adhesives showed better bonding performance than other adhesives. Between polyurethanes adhesives has been found that polyurethanes with higher work of cohesion, work of adhesion and dissipate less energy tend to promote better bonding performance, this result is associated with the ratio between soft and hard segments of polyurethanes. / Os adesivos termofund?veis apresentam a vantagem de n?o liberarem compostos org?nicos vol?teis como os adesivos base solvente, por isto o consumo destes adesivos vem aumentando nos ?ltimos anos. A aplica??o destes adesivos abrange diversos tipos de ?reas como embalagens, cal?ados, moveleiro, entre outros. Desta forma, este trabalho tem como objetivo avaliar a ades?o e a intera??o de adesivos termofund?veis de diferentes naturezas qu?micas (poliamida, poliuretano, EVA, HMPSA a base de borracha e poliolefina) com diferentes substratos (TPU, PVC, TR, laminado sint?tico e couro). Para avaliar a intera??o adesivo-substrato bem como caracterizar adesivos e substratos foram utilizadas as t?cnicas: reologia, an?lise de ?ngulo de contato, FTIR, DRX, analise de rugosidade, RMN-1H, MEV, AFM, DSC, GPC e DMTA. Atrav?s da determina??o da energia superficial e das componentes polares e dispersivas dos adesivos e substratos, foi poss?vel calcular trabalho de ades?o e comparar com o desempenho de colagem. A partir disto, foi poss?vel verificar que os adesivos de poliuretano apresentaram melhor desempenho de colagem que os demais adesivos. Entre os adesivos de poliuretano verificou-se que os poliuretanos que apresentam maior trabalho de coes?o e de ades?o com o substrato e que dissipam menos energia tende a obter melhor desempenho de colagem, este resultado esta associado ? raz?o entre os segmentos flex?veis e r?gidos dos poliuretanos.
127

Estudo de pr?-formula??o e formula??o farmac?utica de uso t?pico contendo Immucillin-DI4G como alternativa terap?utica para o tratamento da Leishmaniose Cut?nea

Pacheco, Fernanda Grendene 14 March 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-05-10T11:50:40Z No. of bitstreams: 1 DIS_FERNANDA_GRENDENE_PACHECO_COMPLETO.pdf: 2728715 bytes, checksum: 93bb3d4fcee10a1e8abba33e2e0e8996 (MD5) / Made available in DSpace on 2016-05-10T11:50:40Z (GMT). No. of bitstreams: 1 DIS_FERNANDA_GRENDENE_PACHECO_COMPLETO.pdf: 2728715 bytes, checksum: 93bb3d4fcee10a1e8abba33e2e0e8996 (MD5) Previous issue date: 2016-03-14 / Introduction: Cutaneous leishmaniasis is caused by Leishmania protozoan and transmitted through the female of Lutzomyia sandflies. The disease can manifest itself in different clinical forms: localized cutaneous leishmaniasis, disseminated cutaneous leishmaniasis, recidivans and diffuse cutaneous leishmaniasis. The North and Northeast (Brazil) are the most affected area by the disease. Pentavalent antimonials and amphotericin B have been the most used drugs for the treatment of this disease but may cause many side effects, which leads the patients to discontinue treatment. Control or progression of the disease has been related to the immune response triggered by the individual. PNP (purine nucleoside phosphorylase) is the key enzyme in the purine salvage route catalyzing the reversible phosphorolysis of purine nucleosides such as deoxyinosine or deoxyguanosine producing their respective bases and deoxyrribose-1-phosphate. The PNP inhibitors can be used for treating diseases caused by disorder mediated by T cells. Immucillin - DI4G (4th generation Immucillin ; 7-((bis(2-hydroxyiethyl)amine)methyl)-1,5-dihydro-4H-pyrrolo[3,2-d]pyrimidin-4-one) is considered as a potent inhibitor of PNP. Objective: development of pre-formulation and formulation studies of a pharmaceutical form for topical use containing Immucillin-DI4G as drug candidate for Cutaneous Leishmaniasis treatment. Material and Methods: Characterization of the compound was performed by NMR, FTIR-ATR and HRMS. The stability of the amorphous powder was evaluated over 90 days using a HPLC method for quantification. Formulations have been developed for stability, rheological and spreadability studies over 30 and 90 days. A method for the quantification of Immucillin-DI4G in the formulation was developed and validated using the HPLC. Results and discussion: The Immucillin - DI4G (amorphous powder) was stable up to 30 days when stored at 4 ?C and 25 ?C. Formulation 1 (Immucillin - DI4G 1.1% Carboxyvinylpolymer gel 2%) was stable only when stored at 4 ?C for a period of 60 days. Formulation 1 was considered as a non-Newtonian fluid with pseudoplastic behavior and no alterations in viscosity was observed over 90 days. On the other hand, significant changes in spreadability was observed when topical formulation was stored at 45 ?C. The formulation containing additives (formulation 2) showed an improvement in stability when stored at 45 ?C for a period of 30 days, but there was a significant decrease in drug content when stored at 4 ?C and 25 ?C. Formulations 3 (Immucillin-DI4G a 1,1% Gel-Cream) and 4 (Immucillin-DI4G 1.1% in Hydroxypropylcellulose polymer at 2%) presented significant loss in the drug content in 30 days when stored at 45 ?C. The results shows that further studies should be conducted in order to analyze the possible degradation products looking for design of novel formulations. / Introdu??o: A Leishmaniose Cut?nea ? causada por protozo?rios do g?nero Leishmania e transmitidas atrav?s das f?meas dos mosquitos do g?nero Lutzomyia. A Leishmaniose cut?nea pode se manifestar de diferentes formas cl?nicas: cut?nea localizada, cut?nea disseminada, recidiva c?tis e cut?nea difusa. A regi?o Norte e Nordeste s?o as mais acometidas pela doen?a. Os antimoniais pentavalentes e a anfotericina B s?o os medicamentos mais utilizados para o tratamento desta doen?a, por?m podem causar v?rios efeitos adversos fazendo com que muitos pacientes abandonem o tratamento. O controle ou a progress?o da doen?a est?o diretamente relacionados com a resposta imunol?gica desencadeada pelo indiv?duo. A PNP ? a enzima chave na rota de salvamento de purinas, catalisa a fosfor?lise revers?vel de nucleos?deos pur?nicos como deoxinosina e deoxiguanosina formando suas respectivas bases e deoxirribose-1-fosfato. Os inibidores da PNP podem ser utilizados para tratamento de doen?as causadas por desordem mediada pelas c?lulas T, atrav?s da inibi??o segura e seletiva da prolifera??o da c?lula T. O Immucillin-DI4G (Immucillin de 4? gera??o; 7-((bis(2-hidroxietil)amino)metil)-1,5-diidro-4H-pirrolo[3,2-d]pirimidin-4-ona) ? considerado como um potente inibidor da PNP. Objetivo: desenvolver estudos de pr?-formula??o e formula??o de uma forma farmac?utica de uso t?pico contendo o Immucillin-DI4G como candidato a f?rmaco para tratamento da Leishmaniose Cut?nea. Materiais e M?todos: Foi realizada a caracteriza??o do composto atrav?s do RMN, EMS e FTIR-ATR. A estabilidade do p? amorfo foi avaliada durante 90 dias, o doseamento foi realizado atrav?s do CLAE. Formula??es foram desenvolvidas para o estudo de estabilidade, estudos reol?gicos e espalhabilidade durante 30 e 90 dias. Um m?todo para o doseamento do f?rmaco nas formula??es foi desenvolvido e validado empregando o m?todo de CLAE. Resultados e discuss?o: O Immucillin-DI4G (p? amorfo) mostrou-se est?vel at? 30 dias quando armazenado a 4 ?C e 25 ?C. A formula??o 1(Immucillin-DI4G a 1,1% em Gel pol?mero Carboxivin?lico a 2% ) mostrou-se est?vel apenas quando armazenada a 4 ?C por um per?odo de 60 dias; ? considerada como um Flu?do N?o-Newtoniano de comportamento pseudopl?stico, sem altera??es na viscosidade durante 90 dias, por?m com altera??es significativas na espalhabilidade quando armazenada a 45 ?C. A formula??o que continha aditivos (formula??o 2) apresentou uma melhora na estabilidade quando armazenada a 45 ?C num per?odo de 30 dias, por?m apresentou queda significativa no teor do f?rmaco quando armazenada a 4 ?C e 25 ?C. As formula??es 3 (Immucillin-DI4G a 1,1% em Creme-Gel) e 4 (Immucillin-DI4G a 1,1% em Gel Pol?mero Hidroxipropilcelulose a 2%) apresentaram perdas significativas no teor do f?rmaco em 30 dias quando armazenadas a 45 ?C. Os resultados demonstram que novos estudos devem ser realizados para a an?lise de poss?veis produtos de degrada??o, para poss?veis ajustes nas formula??es.
128

Obten??o do extrato vol?til de sementes de Anethum graveolens L. por diferentes t?cnicas extrativas / Obtaining volatile extract of Anethum graveolens L. by different extractive techniques

Garcez, Jos? Jacques 03 August 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-09-26T11:17:54Z No. of bitstreams: 1 DIS_JOSE_JACQUES_GARCEZ_COMPLETO.pdf: 2188213 bytes, checksum: 52d9379f9b56a2cbd55ff55765b34197 (MD5) / Made available in DSpace on 2016-09-26T11:17:54Z (GMT). No. of bitstreams: 1 DIS_JOSE_JACQUES_GARCEZ_COMPLETO.pdf: 2188213 bytes, checksum: 52d9379f9b56a2cbd55ff55765b34197 (MD5) Previous issue date: 2016-08-03 / This master thesis aimed the study of different extraction techniques and the influence of different particle sizes in maximizing the yield of essential oil from the seeds of dill, an herb widely used in cooking and in traditional folk medicine and has a wide range of properties conferred such as antimicrobial, antibacterial and antioxidant. The techniques used for obtaining the essential oil were extracted by steam distillation and hydrodistillation, where different average particle sizes of crushed seed and anise were considered, and extraction with supercritical carbon dioxide, where besides the variation of average particle sizes it was used different pressure values. For the supercritical extraction, it was then used the response surface method in which the variables pressure and average particle diameter were investigated, also a 2? factorial design was used to determine the number of experiments required. The best conditions for the three extractive methods were found, being larger diameters of particles to steam distillation and hydrodistillation, and 10,000 kPa and smaller diameter particles to the supercritical extraction. In this evaluation, it was performed mathematical modeling of the yield versus time curves of the best extraction conditions for each of the techniques. The extracts were analyzed in a gas chromatograph coupled to a mass spectrometer, after, the results have undergone a statistical analysis of major components, which were divided into 3 different groups according to their similar compositions. Finally, its antibacterial activities were tested where all extracts showed activity against E. coli. / Este trabalho tem como objetivo o estudo sobre algumas diferentes t?cnicas de extra??o e a influ?ncia de diferentes granulometrias na maximiza??o do rendimento do ?leo essencial das sementes do endro, uma erva utilizada na culin?ria e na medicina popular tradicional e que possui uma ampla gama de propriedades atribu?das tais como atividade antibacteriana, antif?ngica e antioxidante. As t?cnicas realizadas para a obten??o do ?leo essencial foram: extra??o por arraste a vapor e hidrodestila??o, onde diferentes tamanhos m?dios das part?culas de sementes mo?das do endro foram considerados, e extra??o com di?xido de carbono supercr?tico, onde al?m da varia??o dos tamanhos m?dios das part?culas, foram empregados diferentes valores de press?es. Para a extra??o supercr?tica, foi ent?o utilizado o m?todo de superf?cie de respostas onde as vari?veis, press?o e di?metro m?dio de part?culas foram investigados, tamb?m, um planejamento fatorial 2? foi aplicado para determinar a quantidade de experimentos necess?rios. As melhores condi??es nos tr?s m?todos extrativos foram encontradas, sendo maiores di?metros de part?culas para o arraste a vapor e a hidrodestila??o e 10.000 kPa e menor di?metro de part?culas para a extra??o supercr?tica. Al?m desta avalia??o, foram realizadas modelagens matem?ticas das curvas de rendimento versus tempo das melhores condi??es de extra??o referente a cada uma das t?cnicas. Os extratos foram analisados em um cromat?grafo a g?s acoplado a um espectr?metro de massas, ap?s, os resultados passaram por uma an?lise estat?stica de componentes principais, onde foram divididos em tr?s diferentes grupos de acordo com suas semelhantes composi??es. Por fim, suas a??es antibacterianas foram testadas onde todos os extratos apresentaram atividade frente a E. coli.
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La prise en charge d'int??r??ts environnementaux globaux lors de la mise en oeuvre du syst??me qu??b??cois de gouvernance de l'eau

Doiron, Marc-Andr?? January 2014 (has links)
R??sum?? : De par le monde, des populations tentent d???organiser leurs atouts afin de parer ?? l?????ventualit?? d???une v??ritable crise globale d???accessibilit?? ?? l???eau douce au XXIe si??cle. Alors que certains territoires sont aux prises avec un ??tat de p??nurie qui menace la sant?? et la s??curit?? ?? court terme des humains et des ??cosyst??mes qui y vivent, d???autres disposent des ressources requises pour accommoder les multiples usages qui sont faits de l???eau au sein de soci??t??s d??velopp??es. C???est le cas notamment du Qu??bec, qui est en voie de mettre en ??uvre ses propres m??canismes de gouvernance de l???eau, ancr??s dans la gestion int??gr??e par bassin versant. Le pr??sent m??moire vise ?? observer les fondements du syst??me qu??b??cois de gouvernance de l???eau, de mani??re ?? ??valuer dans quelle mesure la province serait apte ?? tenir compte du contexte global de l???eau douce lors de l?????laboration et la mise en place de ses politiques de l???eau. Pour ce faire, une revue sommaire de la litt??rature r??cente est effectu??e, dans les domaines de la gouvernance d??mocratique et environnementale, ainsi que sur les pratiques en gestion des ressources en eau par bassin versant et sur le plan international. Sont aussi ?? l?????tude les lois et politiques qui donnent le cadre pratique de la gouvernance de l???eau au Qu??bec et au Canada. Les r??sultats de cet effort de recherche laissent croire qu???il soit bel et bien possible de mener une discussion voulant que le Qu??bec dispose des outils n??cessaires afin de s?????tablir en tant qu???intendant territorial de la ressource eau sur la sc??ne globale. Cependant, d???une disposition capacitaire d???agir ainsi ne d??coule pas directement le devoir moral de le faire. Cette responsabilisation de l?????tat qu??b??cois face ?? la crise de l???eau doit ??tre v??hicul??e par une volont?? populaire soutenue, d??sireuse de prendre en charge des projets de soci??t?? dont les b??n??fices ?? long terme s?????tendent au-del?? des fronti??res g??opolitiques traditionnellement admises. // Abstract : Over the world, populations are trying to organize their assets in order to face the eventuality of a 21st century global crisis pertaining to the accessibility of freshwater resources. While some territories are hit by water shortages that threaten the health and security of the humans and ecosystems living there, others offer sufficient resources to accommodate the various usages of water that are distinctive of current developed societies. That is notably the case in Quebec, where the province is moving towards implementing its own water governance mechanisms, anchored in integrated watershed resources management. This research report aims to observe the foundations of Quebec???s water governance system, in order to assess to what extent the province might be able to account for the global water context during the development and implementation of its water policies. This is to be done through a cursory review of recent literature, in the fields of democratic and environmental governance as well as those of watershed and international water management practices. Also of interest are the laws and policies that provide the practical framework for water governance in Quebec and in Canada. The results of this exercise tend to show that it is in fact possible to hold a discourse to the effect that the province of Quebec has the necessary tools to establish itself as a territorial steward of water resources on the global scale. However, Quebec???s potential capacity to act in such a way does not directly imply the moral duty to do so. The acknowledgement of moral responsibility towards the water crisis by the Quebec government must be driven by a sustained popular movement that is willing to undertake society-wide projects, the long-term benefits of which carry over traditionally accepted geopolitical boundaries.
130

The effect of silicon, silica and silicates on the osteoblast in vitro

Anderson, Susan Ita January 2001 (has links)
Silica is an essential trace element in human nutrition and dietary deficiency leads to abnormal bone formation in experimental animal studies (Carlisle, 1972, Schwartz 1972). Silica-containing glasses and glass ceramics, within a certain range, are bioactive, forming a strong bond with bone and soft tissue when they are used as bone replacement materials. The aim of this work was to investigate the effect of silica on the osteoblast in vitro with a view to its eventual incorporation into biomaterials to improve bone-bonding properties. Two distinct approaches were used. The first involved the analysis of silica as a nutrient, by supplementing osteoblast growth medium with sodium metasilicate, and evaluating the osteoblast response in terms of cell growth, mineralisation and cytotoxicity. The second approach examined the response of osteoblasts to silica as a biomaterial. A silica gel was used to isolate the effects of silica on the osteoblast in vitro without the effects of the other ions present in bioactive glass. The biocompatibility of patterned silicon wafers was investigated to evaluate the potential use of these materials in the field of biomaterials. Finally, the bioactivity and osteoblast response to a novel silicon/polymer composites as assesseda s a potential biomaterial. The results of nutrition studies showed that in some cases low levels (1-100ppm) of silicate appeared to have a beneficial effect on bone formation in terms of nodule formation and mineralisation. Higher levels of silicate supplementation (>300ppm) caused rapid apoptosis in osteoblasts, fibroblasts and macrophages and affected cell spreading. The biomaterial studies showed that the silica gel surface was bioactive and osteoblasts responded favourably demonstrating enhanced, earlier nodule formation. Bioactive surfaces formed a calcium phosphate (CaPi) layer and released silicic acid when incubated in a simulated body fluid (SBF). Bulk silicon wafers (Si) supported osteoblast growth however, the removal of the oxide layer by wet etching (ESi) imparted bioactive properties to the wafer. Patterned Si/Esi surfaces supported the formation of a CaPi layer over the entire surface and demonstrated osteoblast preferences for bioactive surfaces. The incorporation of silica particles into a bioabsorbable polymer matrix rendered the composite bioactive and supported osteoblast growth. The results of this work demonstrate the importance of silica in bone mineralisation, osteoblast apoptosis and particularly the potential benefits of the use of silica and silicon to improve bone bonding in non-bioactive biomaterials and biosensors.

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