As parasitoses causadas por helmintos constituem um grave problema sanitário, tanto para os seres humanos quanto para os animais, além de gerar grandes prejuízos econômicos. O sulfóxido de albendazol é um fármaco anti-helmíntico de amplo espectro, largamente utilizado na medicina veterinária, veiculado pelas vias oral e parenteral, mediante a utilização de formas farmacêuticas convencionais. Apresenta biodisponibilidade baixa e irregular em função de sua pouca solubilidade nos fluidos biológicos. Para a manutenção da concentração plasmática e completa eliminação dos parasitos, são necessárias administrações reiteradas, ocasionando transtornos decorrentes do manejo freqüente dos animais e do aumento do custo da terapia. O presente trabalho teve como objetivo desenvolver e caracterizar um sistema microparticulado para liberação sustentada de sulfóxido de albendazol, de modo que este pudesse permanecer no organismo dos animais pelo tempo suficiente para a completa eliminação dos parasitos após uma única administração. Os sistemas foram obtidos a utilizando as técnicas de spray-drying e emulsificação / evaporação de solvente, tendo sido utilizados os polímeros Eudragit RS 30 D® e Eudragit RS PO®, respectivamente. As micropartículas obtidas foram caracterizadas com relação ao tamanho, à morfologia e à eficiência de encapsulação. Através da técnica de emulsificação / evaporação de solvente, foram obtidas partículas com diâmetro médio inferior a 300nm, estreita faixa de distribuição de tamanho e eficiência de encapsulação de aproximadamente 60%. Os resultados do estudo in vitro do perfil de liberação do fármaco a partir das micropartículas obtidas mostraram que, apesar de o sistema desenvolvido não ter sido capaz de sustentar a liberação do fármaco, o mesmo promoveu um aumento significativo da solubilidade do sulfóxido de albendazol em pH 7,4, fato este que pode contribuir para o aumento da biodisponibilidade do mesmo após administração parenteral. / The helminthosis are a serious sanitary problem, as for the men than for the animals, besides the great economic lacks. Albendazole sulphoxide is an antihelminthic drug with broad spectrum of action, widely used at veterinarian medicine, throw oral and parentereal vies, in conventional pharmaceutical dosages. It has low and irregular bioavailability due its low solubility in the biological fluids. For the maintenance of the plasmatic concentration and complete elimination of the parasites, it is required several administrations, creating many troubles due the frequent handling of the animals and increase in the costs of the therapy. The present work had as objective to develop and characterize microparticles for sustained release of albendazole sulphoxide, in order that the drug could be for a longer time in the animals organisms and the parasites could be eliminated after just one administration. The referred microparticles were obtained from the spray-drying and emulsification / evaporation of solvent techniques, using the polymers Eudragit RS 30 D® and Eudragit RS PO®, respectively. The obtained systems were characterized considering size, morphology and encapsulation efficiency. Using the emulsification / evaporation of solvent technique, it was prepared microparticles with medium diameter under 300nm, narrow range of size distribution and encapsulation efficiency of about 60%. The results of the in vitro release profile study of the drug from the prepared microparticles showed that besides the developed system was not be able to sustain the drug delivery, it was able to improve significantly the solubility of albendazole sulphoxide at pH 7.4, what can be useful to improve its parenteral bioavailability.

Mutagenesis screening in mice is an effective means of identifying essential genes in cardiovascular development. The l11Jus8 (L8) mutant mouse line was originally isolated from a region-specific N-ethyl-N-nitrosourea (ENU) chemical mutagenesis screen and exhibited an autosomal recessive mid-gestational embryonic lethal phenotype characterised by haemorrhage in the thoracic cavity, blood pooling in the heart, right ventricular dysmorphology and yolk sac vascular degeneration. Prior work mapped the L8 mutation to a ~2.77Mb region on mouse chromosome 11. The aim of this study was to further characterise the L8 mutant phenotype and identify the L8 causative mutation. Phenotypic characterisation conducted here confirmed mid-gestational lethality, haemorrhage and yolk sac vascular degeneration in L8 mutants. Histological analysis of L8 mutants demonstrated presence of fragmented cell nuclei and loss of myocardial integrity in embryonic atrial myocardium. Areas of fragmented cell nuclei did not exhibit positive staining for apoptosis. Furthermore, L8 mutants did not appear to experience typical cardiac defects in aspects including myocardial or smooth muscle differentiation, cell proliferation, ECM production, myocardial hypoplasia/hyperplasia, basement membrane components or observable aberrations in cardiac conduction. L8 mutants exhibited atypical cardiac defects including sudden cessation of heartbeat with morphological indicators of necrosis such as swelling of mitochondria and release of microparticles both from atrial myocardial cells. The L8 mutant appears to represent a novel combination of cardiac defects or novel defects with secondary cardiac phenotypes. Sequencing of the coding exons and splice junctions of 22 candidate genes within the ~2.77Mb L8 locus did not identify the causative mutation. The L8 locus was therefore further refined to a ~1.16Mb region including 20 genes. Sanger sequencing of 10 of these genes plus targeted sequence capture and SOLiD sequencing of the region did not identify a potential L8 mutation. Given the refinement of the candidate locus and advances in sequencing technology and analysis, further sequencing will likely identify the L8 mutation and confirm the cause of the embryonic lethal phenotype.

Orientador: Nelson Eduardo Duran Caballero / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-07T19:54:09Z (GMT). No. of bitstreams: 1 Gaspari_PriscylaDanielyMarcato_M.pdf: 3916509 bytes, checksum: 15b4d148bf7fb5ebc6d8b40b2108c914 (MD5) Previous issue date: 2006 / Resumo: O projeto consistiu na preparação e caracterização de sistemas de liberação sustentada veiculando a estreptomicina, um agente antimicobacteriano. A estreptomicina (STM) foi encapsulada em micropartículas poliméricas preparadas a partir do polímero biodegradável poli(e-caprolactona) (PCL) e do copolímero biodegradável poli(3-hidroxibutirato-co-3-hidroxivalerato) (PHBV), pela técnica de emulsificação seguida da evaporação do solvente. Estas partículas foram caracterizadas quanto ao diâmetro médio e distribuição de tamanho, morfologia, Potencial Zeta e eficiência de encapsulamento. Micropartículas de PCL e PHBV foram obtidas pelo método de dupla emulsão e evaporação de solvente com diferentes morfologias, sendo que as partículas de PCL apresentaram superfície mais lisa do que as de PHBV. Além disto, a adição do co-solvente acetona na fase orgânica, provocou a formação de micropartículas de PHBV maiores e mais porosas. Alterações em parâmetros da preparação como, aumento da concentração do tensoativo, evaporação de solvente a baixa pressão e uso de polímero com menor massa molar foram fatores que reduziram do diâmetro das partículas. A eficiência de encapsulamento nas micropartículas de PHBV, medida por eletroforese capilar, foi de 43 ± 4 %. No ensaio biológico in vitro em células V- 79 (células de fibroblastos de pulmão derivadas de hamsters chineses), hepatócitos e Vero (células do rim de macaco) foi verificada baixa toxicidade do antibiótico estreptomicina nos alvos celulares avaliados (captura do corante vermelho neutro, conteúdo de ácidos nucléicos e redução do corante metiltiazoletetrazolium). Entretanto, as micropartículas de PHBV com e sem fármaco apresentaram alteração no lisossoma, que pode ter sido causada pela presença de PVA na superfície das partículas. A atividade antimicrobiana da estreptomicina livre e encapsulada frente à Escherichia coli foi verificada, obtendo menor eficiência do fármaco encapsulado em relação ao fármaco livre. Entretanto, nos testes frente à Streptococcus lentus, foi verificada maior eficiência quando o fármaco estava encapsulado. / Abstract: This research was related to the preparation and characterization of a sustained release system with streptomycin, an antimycobacterial agent. The streptomycin (STM) was encapsulated in polymeric micro and nanopartículas from the biodegradable polymers, poli(e-caprolactona) (PCL) and of the biodegradable copolymers, poli(3-hydroxybutirate-co-3-hydroxyvalerate) (PHBV), by double emulsion and solvent evaporation method. These particles were characterized in function of the size and size distribution, morphology, Potential Zeta and encapsulation efficiency. PCL and PHBV microparticles that were obtained by described methods, PCL presented surface smoother than the PHBV microparticles. Moreover, the addiction of the co-solvent acetone in the organic phase provoked the formation of PHBV microparticles larger and more porous than in PCL. Alterations in preparation parameters such as increase of the surfactant concentration, solvent evaporation in low pressure and a decrease molar mass were factors that reduced the particle sizes. The encapsulation efficiency in microparticles of PHBV, measured by capillary electrophoresis, it was 43 ± 4.4%. In the in vitro biological assay in V-79 cells (permanent lung fibroblasts cell line derived from Chinese hamsters), hepatocytes and Vero cells (from monkey kidney) was verified low toxicity of the streptomycin in the endpoints targets (neutral red uptake, nucleic acid content and tetrazolium reduction). However, microparticles of PHBV with and without drug demonstrated an alteration in the lysosome that it could have been caused by the presence of poly vinylic alcohol (PVA) in the particles surfaces. The antimicrobial activity of free and encapsulated streptomycin against Escherichia coli was demonstrated. A smaller efficiency of encapsulated drug than the free one was found. However, in the tests against Streptococcus lentus was verified larger efficiency of the free drug than the encapsulated one. / Mestrado / Físico-Química / Mestre em Química

Orientadores: Priscilla Efraim, Ana Paula Badan Ribeiro / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T16:56:00Z (GMT). No. of bitstreams: 1 Lopes_JuliceDutra_D.pdf: 26424877 bytes, checksum: eced1650a81af1c56e7eb7df9b5ca109 (MD5) Previous issue date: 2015 / Resumo: A cristalização de gorduras é um fenômeno complexo que, se controlada, pode ser aplicada em diversos setores das indústrias químicas e de alimentos. Na produção de chocolates, o uso de agentes ativos de nucleação pode se dar pela incorporação de triacilgliceróis de alto ponto de fusão, fundidos ou na forma sólida, à massa de chocolate ou à manteiga de cacau, resultando em um grande número de núcleos de cristalização bem definidos, que consistem na base para a ordenação estrutural do sistema, podendo melhorar e/ou acelerar a etapa de temperagem de chocolates. Baseando-se nestes fatos, o objetivo deste trabalho foi produzir e caracterizar micropartículas lipídicas sólidas (SLM) de óleos totalmente hidrogenados (hardfats) de palma (FHPO), algodão (FHCO), soja (FHSO) e crambe (FHCrO) utilizando a técnica de spray cooling (SC), a fim de se estudar a influência da adição dessas SLM como agentes de nucleação no processo de temperagem de chocolate amargo. As SLM foram produzidas variando-se os parâmetros de processo: temperatura de manutenção dos hardfats (70 a 85 °C), temperatura de solidificação das SLM (0 a 24 °C), diâmetro do atomizador (0,7 e 1 mm) e pressão do ar comprimido de atomização (1,25 a 1,75 kgf/cm2). As SLM produzidas apresentaram polimorfismo ?, formato esférico e diâmetros médios entre 56,12 e 2514,32 ?m, dependendo dos hardfats e das condições de processo utilizadas. A cinética de transição polimórfica das SLM acondicionadas a 25, 35 e 45 °C foi investigada por 141 dias, avaliando-se a configuração visual, o comportamento térmico de fusão e o polimorfismo das SLM. A transição completa das SLM para o polimorfismo de seus respectivos hardfats ocorreu de forma mais rápida no acondicionamento a 45 °C, com transição completa observada nas SLM do FHSO, FHPO e FHCO após 24 h, sem alteração do aspecto visual. Em 35 °C, a transição das SLM do FHPO e FHCO ocorreu após 4 dias e em 25 °C observou-se transição completa apenas nas SLM do FHCO. Para as SLM do FHCrO o polimorfismo ? foi predominante nos tratamentos a 25 e 35 °C e só houve transição polimórfica no tratamento a 45°C após 15 dias. Observou-se redução do tempo da etapa de temperagem de chocolates adicionados de SLM do FHSO com polimorfismo ?, os quais apresentaram tensão de ruptura e cor similares às de chocolates submetidos à temperagem realizada da forma convencional. Os resultados indicam que a técnica de SC é adequada para produção de SLM dos hardfats estudados. Porém, para o uso destas SLM como agentes de cristalização é necessária a indução da transição polimórfica para o polimorfismo mais estável, preferencialmente de forma não estática, para evitar a formação de aglomerados / Abstract: Fats crystallization is a complex phenomenon which, when controlled, can be applied in several chemical and food industries sectors. In chocolate production, the use of nucleating agents can occur by the incorporation of high melting point triglycerides, melted or in solid form. The seeds can be added directly in the chocolate mass or in the cocoa butter, resulting in a large number of well-defined crystallization nuclei, which are the basis for the structural arrangement of the fat crystal network. In this way, the seeds can improve and/or accelerate the chocolate tempering step. Based on these facts, the objective of this research was to produce and to characterize solid lipid microparticles (SLM) from fully hydrogenated oils (hardfats) of palm (FHPO), cottonseed (FHCO), soybean (FHSO) and crambe (FHCrO), using the spray cooling (SC) technique in order to study the influence of the addition of these SLM as nucleating agents in dark chocolate tempering process. The SLM were produced by varying the process parameters: hardfats maintenance temperature (70 to 85 °C), SLM solidification temperature (0 to 24 °C), nozzle diameter (0.7 to 1 mm) and atomiser air pressure (1.25 to 1.75 kgf/cm2). The SLM produced presented ? polymorphism, spherical shape and mean diameter between 56.12 and 2514.32 µm, depending on the hardfats and process conditions used. The polymorphic transition kinetics of SLM stored at 25, 35 and 45 °C was investigated by 141 days evaluating the visual configuration, the thermal melting behavior and the SLM polymorphism. The full transition from SLM to polymorphism of their respective hardfats occurred more quickly at 45 °C, with full transition of SLM observed in the SLM of FHSO, FHPO and FHCO after 24 hours, without altering the visual aspect. At 35 °C, the SLM transition of FHPO and FHCO occurred after 4 days, and at 25 °C the complete transition was observed only in the SLM of FHCO. For SLM of FHCrO, ? polymorphism was predominant in the treatments at 25 and 35 °C and there was only polymorphic transition in the treatment at 45 °C after 15 days. It was observed time reduction on the tempering chocolates steps with the addition of SLM of FHSO with ? polymorphism, which showed similar rupture tension and color to the chocolate subjected to the conventional way of tempering. The results indicate that SC technique is suitable for the SLM production of the studied hardfats. However, for use of these SLM as crystallization agents is required to induce the polymorphic transition for the most stable polymorph, preferably non-static way in order to avoid the agglomerates formation / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos

A calcificação ocorre pela formação de depósitos de cálcio em diferentes matrizes envolvendo fatores mecânicos, químicos e biológicos. Alguns compósitos, polímeros e proteínas são utilizados na formação de matrizes por promover maior eficiência no processo de mineralização. Estima-se que a fibroína da seda apresente também esta finalidade. A fibroína é uma proteína fibrosa extraída do casulo do bicho-da-seda (Bombyx mori), que pode ser processada como filme, membrana, esponja, pó, gel e aplicada em ossos e cartilagens, enxertos vasculares, reparação de nervos e córnea, como sistema de liberação de drogas, suturas, ligamentos, peles, tendões e substrato para cultura de células. Nesse trabalho houve a preparação de micropartículas de fibroína da seda através de dois procedimentos distintos, um por borrifamento em N&sup2 e outro por borrifamento em Na2HPO4 e o processo de calcificação realizado foi por imersão alternada de soluções tamponadas de cálcio e fosfato. As caracterizações realizadas foram Espectroscopia de Absorção no Infravermelho (FT-IR), Análise Termogravimétrica (TGA), Microscopia Eletrônica de Varredura (MEV), Espectroscopia de Energia Dispersiva (EDS) e Calorimetria Exploratória Diferencial (DSC). Os resultados obtidos mostraram que a calcificação das micropartículas de fibroína ocorre pelas duas metodologias empregadas. O teor de calcificação foi de aproximadamente 29% para micropartículas borrifadas em N&sup2 e de aproximadamente 80% para as micropartículas borrifadas em Na2HPO4. As micropartículas de fibroína calcificadas, não apresentaram transição térmica até a temperatura de 120°C, possibilitando a esterilização em autoclave a seco. / Calcification occurs by the formation of calcium deposits in different matrices involving mechanical factors, chemical and biological. Some composites, polymers, and proteins are used in forming matrices to promote higher efficiency in the process of mineralization. It is estimated that the silk fibroin also present for this purpose. The fibroin is a fibrous protein extracted from silkworm cocoon silkworm (Bombyx mori), which can be processed as film, membrane, sponge, powder, gel and applied in bone and cartilage, vascular grafts, nerve repair and corneal as a delivery system for drugs, sutures, ligaments, skins, tendons and substrate for cell culture. In this work was the preparation of microparticles of silk fibroin by two different procedures, sputter under N&sup2 and in other sputter Na2HPO4 and calcification process was performed by immersion of alternating buffered solutions of calcium and phosphate. The characterizations were performed Absorption Spectroscopy Infrared (FT-IR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and Differential Scanning Calorimetry (DSC). The results showed that the calcification of fibroin microparticles occurs by the two methodologies. The calcified fibroin microparticles showed no thermal transition temperature to 120°C, enabling autoclaving of the microparticles dry

A laboratory process exists for the extraction of kafirin protein from sorghum grain in order to form kafirin encapsulating microparticles. This laboratory process extracts approximately 2 g of protein and takes in excess of 60 hours from start to finish. A scaled-up extraction process based on the current laboratory process, consisting of a 100 L extraction vessel, was established in order to extract large volumes of kafirin protein from sorghum grain. Approximately 2.5 kg of kafirin protein, which contained approximately 80 % protein after defatting, was extracted from red sorghum grain. This blended kafirin protein, which was the product of combining 9 batches done on the up-scaled process, was needed in order to obtain a consistent base raw material for further experimentation. The blended kafirin was used to investigate the formation of kafirin encapsulating microparticles. This was achieved by means of the solvent phase separation technique with acetic acid as the solvent phase. A series of experiments, selected from a partial factorial design, were used to screen how the formation of microparticles was affected by various parameters. The parameters investigated were solvent to protein ratio, stirring speed, water addition rate and number of water droplets. The morphology of the various microparticles produced was analysed by means of light microscopy, FTIR and particle size analysis, and the different formed microparticles characterised. From the screening partial factorial experimental design, it was determined that the acetic acid concentration was crucial for the formation of microparticles. Microparticles did not form at a low mass ratio (2.3) of glacial acetic acid solvent to protein. Water addition rate and stirring rate also affected microparticle formation while the number of water droplets was insignificant. Therefore, using a high solvent to protein mass ratio (6.8), additional refined partial factorial experiments were conducted. These experiments focused on the effect of water addition rate and stirring speed on the final kafirin microparticle size. Ultimately, a polynomial model was developed to predict the final kafirin microparticle size using only the water addition rate and stirring speed as inputs. The model had an R2 value of 0.986 and was found to relatively accurate during validation. The model also identified that three distinct regions existed within the workspace: _ A region containing large particles due to protein mass agglomeration and crosslinking, which occurs at low stirring speeds (< 400 rpm) and high water addition rates (> 5 mL/min) _ A region where only small individual microparticles exist, which occurs at high stirring speeds (< 800 rpm) and low water addition rates (> 2 mL/min) _ A region where moderate particles existed as uniform agglomerates of the microparticles, which occurs at moderate stirring speeds (+- 600 rpm) and moderate water addition rates (+- 3.5 mL/min) Ultimately these kafirin microparticles, prepared from protein extracted in an up scaled process, were used to form qualitative microparticle films. The microparticle films were made without plasticiser and without dewatering the microparticles. Furthermore these films were made from microparticles in the regions identified in the model. This qualitative film formation showed that agglomerated microparticles can form films. This could be beneficial for the feasibility of a commercialised process for kafirin microparticle films since the production time would be shorter and less energy intensive. / Dissertation (MEng)--University of Pretoria, 2016. / Chemical Engineering / MEng / Unrestricted

No description available.

Since the approval of recombinant human insulin in 1982, there has been a growing interest in the use of biotherapeutics, and more particularly of monoclonal antibodies (mAb)-based products due to their multiple advantages compared to small chemical entities. Nonetheless, mAbs also show some drawbacks, one of them being their sensitivity to diverse instability pathways due to their complex structure. Therefore, attention needs to be paid during formulation and storage of such entities. While administration of mAbs using non-invasive routes has been extensively investigated, it still faces several challenges, especially regarding systemic therapy. Thus, parenteral route currently remains the main route of administration for antibodies (Abs). However, frequent injections are required in order to maintain Ab plasma levels into the therapeutic range, which may induce peak-to-trough fluctuations in blood levels due to multiple dosing as well as poor patient compliance. Consequently, methods to increase the half-life of Abs have gained interest over the last decades, and more particularly the use of sustained-delivery systems based on poly(lactide-co-glycolide) acid (PLGA) derivatives. In this work, the spray-drying of a water-in-oil emulsion (w/o) was selected as the formulation technique to produce Ab-loaded PLGA microparticles. Based on the requirement of sustained-release delivery systems, different objectives were set regarding the characteristics of the microparticles, i.e. a drug loading (DL) of at least 20%, a continuous in vitro and in vivo Ab release over a minimum of one month with a limited burst release and the possibility to maintain Ab stability during manufacturing, storage and release. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished

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No description available.