In this study, it is aimed to develop an injectable controlled release system of PCL and P(L,DL)LA microspheres loaded with TA and/or Ral for local treatment of rheumatoid arthritis which will avoid from systemic side effects of traditional administration and eliminate problems caused by direct local injections. Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune disorder that most commonly causes inflammation and tissue damage in joints and tendon sheaths. Current strategies for the disease are mainly towards relieving symptoms and increasing mobility. The microsphere form drug delivery systems were developed to enhance the treatment success of rheumatic diseases by providing these agents alone or together for long terms without causing systemic or local site effects upon injection to the RA joints. Microspheres were prepared with s/o/w solvent evaporation technique and optimized to achieve a suitable size for joint application, to sustain the delivery of the drug(s), to provide required amount of the agent with feasible amount of microsphere. In order to manage these, microspheres prepared with different combinations of polymers and drugs were examined for particle size analysis, surface and structural characterizations, time related drug release properties, and drug loading capacities. In vitro cytotoxicity tests using 3T3 fibroblast cells were done to evaluate the biocompatibility of drug loaded PCL microspheres. The degradation of polymers were conducted and evaluated by GPC analysis. In PCL:TA microspheres, as polymer:drug ratio decreased (from 10:1 towards 10:4), namely as the drug partition increased, it was seen that encapsulation efficiency and loading percentages increased. Meanwhile, percent release of the drug decreased, indicating more prolonged release. Among all microspheres, PCL:TA 10:4 and PCL:Ral 10:2 were found to be the most appropriate for dual release in terms of release values (ca 21% and 0.09%, respectively), loadings (ca 27% and ca 13%, respectively) and mean particle size values (ca 100 &mu / m and ca 95 &mu / m, respectively). After release studies, microspheres preserved their sphericity. These selected polymer:drug groups also represented no cytotoxic effect. The microspheres for dual drug study (PCL:TA:Ral 10:4:2) released app. 55% of its TA and 0.29% of Ral at the end of 4 weeks. Drug loading capacities of these microspheres were found to be ca 14% for TA and 8% for Ral. Furthermore, with dual loading case, smallest mean particle size (68 &mu / m) could be obtained among all studied groups. P(L,DL)LA microspheres caused high viscosity problems during microsphere preparation steps and resulted in the slowest release, which was unfavorable for the aim of the study. To our knowledge there is no microsphere study reported with P(L,DL)LA in literature. The TA and Ral delivery systems with PCL and P(L,DL)LA were developed and studied for the first time in literature and they were optimized for RA treatment purposes. The potential of these systems, should be further tested in experimental animal models of RA.

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The aim of this thesis is to determine the feasibility of an injectable delivery system based on 5-ethylene ketal ε-caprolactone for localized delivery of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) for treating critical limb ischemia. HGF and VEGF were chosen because of their ability to simultaneously stimulate the proliferation and migration of endothelial cells, to initiate the formation of blood vessels and the recruitment of pericytes to stabilize the blood vessels. Homopolymer of 5-ethylene ketal ε-caprolactone and its copolymer with D,L-Lactide were synthesized by ring opening polymerization using hydrophobic initiator (octan-1-ol) or an hydrophilic initiator (MPEG), and stannous octanoate as a co-initiator/catalyst. The resulting polymers were amorphous and viscous liquids at room temperature. The viscosity, biodegradation rate, and release rate were varied by copolymerizing with D,L-lactide and/or initiating with MPEG or octan-1-ol. In vitro, the polymers degraded with surface erosion characterized by a nearly linear mass loss with time with no significant change in number average molecular weight and glass transition temperature. The ratio of EKC to DLLA in the copolymer remained the same throughout the degradation studies. A similar degradation mechanism was observed in vivo when the copolymer initiated with octan-1-ol was implanted subcutaneously in rats. In vivo, the polymer exhibited a moderate chronic inflammatory response, characterized by the presence of neutrophils, macrophages, fibroblasts and fibrous capsule formation. The inflammatory response decreased with time but was still on going after 18 weeks of subcutaneous implantation. Protein release from the polymer was transported by convection through the hydrated polymer region, at a rate determined by the osmotic pressure generated and the hydraulic conductivity of the polymer. Highly bioactive VEGF and HGF were released in a sustained manner, without burst effect for over 41 days when delivered simultaneously, using the osmotic release mechanism. VEGF was released at the rate of 36 ± 7 ng/day for 41 days, while HGF was released at the rate of 16 ± 2 ng/day for 70 days. Factors that influenced release of proteins were their solubility in the concentrated trehalose solution and hydraulic permeability of the polymer. This delivery system can serve as a potential vehicle for controlled release of VEGF and HGF for treating critical limb ischemia or the controlled release of other proteins for other clinical applications. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-05-23 10:18:48.307

Zeolites have been used in agriculture since the 1960s, due to the effectiveness of these crystalline microporous solids as soil amendments for plant growth, their cation exchange capacity (CEC) and slow-release fertilizer properties. Most work on slow-release fertilizers has focused on natural Clinoptilolite, Phillipsite and Chabazite. The aim of this study was to synthesize zeolites, study their effectiveness as soil amendments and their ability to act as controlled release fertilizers to decrease nitrate leaching. Nitrate pollution of groundwater is a major agro-environmental concern. The zeolites Phillipsite and Linde-type F were synthesized from aluminosilicate gels; ion exchanged to introduce ammonium and characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), Thermo-gravimetric analysis (TGA) and Scanning electron microscopy (SEM) techniques, both before and after ion exchange. Ammoniumexchanged Phillipsites (natural and synthetic), ammonium-exchanged synthetic Linde-type F (the zeolite having highest affinity towards ammonium) and ammonium exchanged Phillipsites (high crystalline and high aluminium) were compared with conventional NPK fertilizer.Three glasshouse experiments were performed to study the effects of zeolite-amended soils on maize growth. Ion exchanged synthetic and natural Phillipsites were first used as soil amendments (w/w 2, 4, 8% zeolite to soil). Synthetic Phillipsite, at 2% loading, resulted in the most significant improvement in both plant growth and phased ammonium release. The synthetic ammonium-exchanged zeolites Phillipsite and Linde-type F (at w/w 1, 2, 4%) were then compared; synthetic Phillipsite, at 2% loading, again resulted in the most significant plant growth response with an increase (≥15%) in shoot dry weight and a decrease (≥30%) in nitrate leaching. Experiments using unexchanged synthetic Phillipsite (at w/w 2%), but with added NPK fertilizer, showed increased plant growth and decreased nitrate leaching, compared with parallel experiments containing unexchanged synthetic Linde-type F (at w/w 2%) and a conventional fertilizer amended soil. This revealed the beneficial effect of Phillipsite for soil amendment, even without ion exchange to the ammonium form. To study the physico-chemical properties affecting the release of ammonium from the Phillipsite framework; high crystalline/low aluminium and low crystalline/high aluminium forms were synthesized and ion exchanged. Both forms were introduced as soil amendments (at w/w 1 and 2%) and experiments showed that the lower zeolite crystallinity decreased cation exchange and therefore decreased nitrate leaching. Experimental results from the glasshouse experiments and cation exchange capacity (CEC) experiments suggest that synthetic Phillipsite, at lower loadings (1 and 2% w/w zeolite to soil) have most potential as soil amendments for both plant growth and controlled-release applications. This conclusion is supported by soil leachate and shoots dry weight analysis. Furthermore, Phillipsite, synthesized in a low crystalline and low ammonium form, may be an even better soil amendment for controlled release of ammonium, which will thereby further decrease nitrate pollution.

The question of whether or not to release an accused on bail pending case resolution involves an evaluation of the risk the accused poses to the community. In addition to this evaluation, the risk posed to the reputation of the criminal justice system should the accused re-offend while on bail has come to influence the timeliness of the bail decision as well as the conditions of the release order. It appears that questions of institutional risk have intensified strategies of process, whereby the bail decision making process has come to take considerably longer as court actors postpone making the release decision. This organizational culture of risk aversion is evidenced in the growing remand population, the dominance of adjournment requests, the presumption of surety supervision, as well as the imposition of numerous restrictive conditions of release that are questionably related to the grounds for detention and allegations of the offence. Due to the additional protections contained in the Youth Criminal Justice Act (YCJA), the expectation is bail should be more liberally used for youths. However, despite the additional legislated protections, bail practices for both adults and youths are operating in remarkably similar ways. Indeed, it appears that routine bail practices for both adults and youths are inconsistent with the essential principles of the bail process. In Canada there is a presumption in favour of release on bail and a presumption of release on the least restrictive form of release appropriate in the circumstances. Despite these principles there has been a relatively steady increase in the size of the remand population in Canada. Focusing on the situation in Ontario, this dissertation examines the bail process in an effort to understand how the remand population has come to exceed the population of sentenced prisoners in provincial prisons for both adults and youths.

The question of whether or not to release an accused on bail pending case resolution involves an evaluation of the risk the accused poses to the community. In addition to this evaluation, the risk posed to the reputation of the criminal justice system should the accused re-offend while on bail has come to influence the timeliness of the bail decision as well as the conditions of the release order. It appears that questions of institutional risk have intensified strategies of process, whereby the bail decision making process has come to take considerably longer as court actors postpone making the release decision. This organizational culture of risk aversion is evidenced in the growing remand population, the dominance of adjournment requests, the presumption of surety supervision, as well as the imposition of numerous restrictive conditions of release that are questionably related to the grounds for detention and allegations of the offence. Due to the additional protections contained in the Youth Criminal Justice Act (YCJA), the expectation is bail should be more liberally used for youths. However, despite the additional legislated protections, bail practices for both adults and youths are operating in remarkably similar ways. Indeed, it appears that routine bail practices for both adults and youths are inconsistent with the essential principles of the bail process. In Canada there is a presumption in favour of release on bail and a presumption of release on the least restrictive form of release appropriate in the circumstances. Despite these principles there has been a relatively steady increase in the size of the remand population in Canada. Focusing on the situation in Ontario, this dissertation examines the bail process in an effort to understand how the remand population has come to exceed the population of sentenced prisoners in provincial prisons for both adults and youths.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-05T19:05:37Z No. of bitstreams: 1 IMARALLY VITOR DE SOUZA RIBEIRO NASCIMENTO - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2760797 bytes, checksum: 7ecba4dc55afbb264d93e04510c69d66 (MD5) / Made available in DSpace on 2018-04-05T19:05:37Z (GMT). No. of bitstreams: 1 IMARALLY VITOR DE SOUZA RIBEIRO NASCIMENTO - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2760797 bytes, checksum: 7ecba4dc55afbb264d93e04510c69d66 (MD5) Previous issue date: 2014-08-29 / Capes / Os sistemas de liberação controlada de fármacos oferecem inúmeras vantagens quando comparados a outros de dosagem convencional tendo os polissacarídeos biodegradáveis ganhando bastante aceitação no desenvolvimento desses sistemas. A quitosana é um exemplo de polissacarídeo biodegradáveis, cuja taxa de liberação pode ser modulada a partir da reticulação iônica com o Tripolifosfato de sódio (TPP). A piperina é um dos principais constituintes da pimenta negra, possuindo diversas ações farmacológicas que podem causar a morte de células cancerígenas e quando conjugada com a quitosana apresenta melhor biodisponibilidade e ação mais rápida. Sendo assim, esse trabalho objetivou desenvolver e avaliar comparativamente membranas poliméricas de quitosana e quitosana reticulada pelo TPP para uso em sistema de liberação controlada de piperina, com a finalidade de obter uma via alternativa para a administração desse fármaco. A piperina foi adicionada sob agitação constante à solução de quitosana e as membranas foram obtidas pelo método de evaporação do solvente. As membranas desenvolvidas foram caracterizadas pelas técnicas de Espectroscopia na Região do Infravermelho com Transformada de Fourier (FTIR), Difração de Raios X (DRX), Microscopia Ótica (MO), Microscopia Eletrônica de Varredura (MEV), Espectroscopia por Energia Dispersiva de Raios X (EDS), Análise Termogravimétrica (TG), Análise de Calorimetria Exploratória Diferencia (DSC), Eficiência de Carregamento (EC) através da Cromatografia Liquida de Ultra Eficiência (CLUE), Avaliação da Viabilidade Celular dos Macrófagos (MTT). Observou-se na análise por FTIR bandas características da quitosana, do agente reticulante e da piperina, como também bandas que caracterizam uma interação entre a quitosana e a piperina. A técnica de DRX demonstrou alteração no caráter semicristalino da quitosana com a presença da piperina e do tripolifosfato. Foi possível perceber, através das técnicas de MO e MEV, alteração na morfologia da membrana contendo piperina quando comparada a de quitosana pura, com a presença de partículas fibrilares. As análises de TG e DSC evidenciaram que quando a piperina foi adicionada à quitosana esta proporcionou uma maior estabilidade térmica ao sistema. O ensaio eficiência de carregamento evidenciou que a extração do o fármaco foi eficaz e que a reticulação influenciou na extração deste. As membranas desenvolvidas apresentaram potencial citotóxico para as células de câncer mamário humano MCF 7. Nas condições desenvolvidas nesta pesquisa o sistema indicado como referência para ensaios de liberação e novos ensaios biológicos é o sistema MQPR. Diante do exposto o sistema desenvolvido apresenta-se como promissor para a obtenção de um sistema para liberação controlada de fármacos. / Controlled drug delivery systems offer many advantages when compared to other conventional dosage methods with biodegradable polysaccharides gaining enough acceptance in the development of these systems. Chitosan is an example of a biodegradable polysaccharide, whose rate of release can be modulated from the ionic crosslinking with sodium tripolyphosphate (TPP). Piperine is one of the major constituent of black pepper, having many pharmacological actions that can cause the death of cancer cells and when combined with chitosan has better bioavailability and faster action. Therefore, this study aimed to develop and comparatively evaluate polymer membranes of chitosan and crosslinked chitosan by TPP to be used in a controlled release system of piperine, in order to obtain an alternative route for the administration of this drug system. Piperine was added under constant stirring to the solution of chitosan and membranes were obtained by the solvent evaporation method. The developed membranes were characterized by the techniques of Infrared Spectroscopy in the Region Fourier Transform (FTIR), X-ray Diffraction (XRD), Optical Microscopy (OM), scanning electron microscopy (SEM), Energy Dispersive Spectroscopy X-Ray (EDS), Thermogravimetric Analysis (TGA), Scanning Calorimetry Analysis of Difference (DSC), Efficiency Charge (EC) by liquid Chromatography Ultra Efficiency (HPLC), Assessment of Cell Viability of Macrophages (MTT). It was observed by FTIR analysis, bands characteristic of chitosan, the crosslinking agent and piperine, as well as bands characterizing an interaction between chitosan and piperine. The XRD technique showed change in semi-crystalline nature of chitosan in the presence of piperine and tripolyphosphate. It was possible to see, through the techniques of OM and SEM, changes in the morphology of the membrane containing piperine compared to pure chitosan, with the presence of fibrillar particles. TG analysis showed that, when piperine was added to the chitosan it provided a smaller weight loss of the system, showing the interaction between chitosan and piperine. DSC analysis showed that addition of piperine into chitosan provided greater stability to the system. The charging efficiency test showed that the drug can be entrapped by 57% in the uncrosslinked membranes and crosslinking influenced the extraction of drug. The developed membranes showed cytotoxic potential for human breast cancer cells MCF 7. Under the developed conditions in this research, MQPR system was shown as a reference for drug delivery testing and new biological tests. Given the above, the developed system is presented as promising for obtaining a system for controlled release of drugs.

Made available in DSpace on 2014-10-09T12:46:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:41Z (GMT). No. of bitstreams: 1 07538.pdf: 15080131 bytes, checksum: 61c8c07c573a7c36c667a13b30f71666 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Made available in DSpace on 2014-06-12T15:53:51Z (GMT). No. of bitstreams: 2 arquivo1933_1.pdf: 2116074 bytes, checksum: 1144c9fce7906fba6fc1437ad2a4c27b (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Reuso de software é um aspecto chave para organizações interessadas em obter melhorias de produtividade, qualidade e redução de custos. Linhas de Produto de Software é uma abordagem de reúso de software que provou seus benefícios em diferentes contextos industriais (Weiss et al., 2006). Em termos de evolução, uma linha de produtos é um conjunto em contínua evolução, e por isso, sua evolução precisa ser gerenciada para que se alcance os benefícios dessa abordagem. O fato de um core asset ser compartilhado entre produtos, e todas as mudanças neste core asset poder ter efeito sobre diversos produtos (McGregor, 2003), aliado ao fato que em linhas de produto de software é preciso lidar com evolução no tempo (versões) e também evolução no espaço (variabilidade) (Krueger, 2002), faz com que o gerenciamento da evolução (mudanças) em linhas de produto de software seja mais complexo e mais desafiador do que o desenvolvimento tradicional de sistemas únicos (Pussinen, 2002). Portanto, a evolução dos core assets e também dos produtos precisa ser bem gerenciada para minimizar os problemas causados por ela. Este desafio envolve diferentes soluções, como questões técnicas, gerenciais e processuais. Desta forma, o foco desta dissertação está nos problemas ligados ao processo de gerenciamento evolução em linhas de produto de software. Neste contexto, este trabalho apresenta o RiPLE-EM, que é um processo para gerenciamento da evolução. Este processo é uma forma sistemática de guiar e gerenciar a evolução de cada core asset e cada produto, englobando atividades de gerenciamento de mudanças, builds, e entregas. Esta dissertação também apresenta a validação inicial do RiPLE-EM, seguindo guias bem estabelecidos de experimentação de software (Wohlin et al., 2000), e de acordo com os dados coletados e analisados na experimentação, RiPLE-EM mostra indicações de que seja um processo viável para o gerenciamento da evolução em linhas de produto de software

Made available in DSpace on 2014-10-09T12:46:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:41Z (GMT). No. of bitstreams: 1 07538.pdf: 15080131 bytes, checksum: 61c8c07c573a7c36c667a13b30f71666 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP