Made available in DSpace on 2014-07-29T15:13:47Z (GMT). No. of bitstreams: 1 TESE Julia de Miranda Moraes.pdf: 2895250 bytes, checksum: e061f736f6922f781b2c671bf4f90f32 (MD5) Previous issue date: 2012-08-17 / The aim of this work was to evaluate the regeneration of equine ulnar nerves submitted to neurotomy, silicone tubing and cell therapy with bone marrow mononuclear cells fraction (MCF) or adipose derived mesenchymal stem cells (ADSC). Fifteen adult horses were divided into three groups with five animals each: control group (CG) with the use of saline solution, group with FCM deposition and group with ADSC deposition. The same surgical procedure was performed in all groups, using both nerves of each animal (right and left), establishing two moments of biopsy: on the 13th week on the right limb (CG1, MCF1 and ADSC1) and on the 26th week on the left limb (CG2, MCF2 and ADSC2). The MCF and ADSC were obtained respectively, from bone marrow and adipose tissue from each animal, both used as an authologous implant. After 13 and 26 weeks, biopsies were performed in all groups and immediately it was made some fragments slide imprints for viewing the nanocrystal fluorescent label. The fragments were fixed in 10% buffered formalin for histological analysis, with HE, luxol fast blue, Masson's trichrome, immunohistochemistry against the antibodies neurofilament (NF), S-100, FGF-2 and GDNF. Microscopically it was observed the presence of axonal growth, connective tissue, inflammatory infiltrate, Schwann cells, neural growth factors, myelin sheath and wallerian degeneration. For histologic analysis, it was established qualitative scores and for immunohistochemistry it was performed quantitative analysis with Image J program. It was observed wallerian degeneration reduction, better fascicular reorganization, new collagen increased, myelin sheath early formation, and NF antibody stronger staining in the experimental groups compared to CG. The ADSC group presented the best results than the other groups, showing ADSCs efficiency compared to MCF and CG for peripheral nerve regeneration. However, it was proved a longer time necessity to occur complete regeneration of peripheral nerve after injury. / Este trabalho teve por objetivo avaliar a regeneração do nervo ulnar de equinos, submetidos à neurotomia, tubulização com tubo de silicone e terapia celular com fração de células mononucleares da medula óssea (FCM) ou células-tronco mesenquimais do tecido adiposo (ADSC). Foram utilizados 15 equinos adultos alocados em três grupos, com cinco animais em cada: grupo controle (GC) com utilização de soro fisiológico; grupo com deposição de FCM; e grupo com deposição de ADSC. Foi realizado o mesmo procedimento cirúrgico em todos os grupos, utilizando-se os dois nervos de cada animal (direito e esquerdo), e estabelecido dois momentos de biopsia: na 13ª semana com biopsia no membro direiro (GC1, FCM1 e ADSC1) e na 26ª semana com biopsia no membro esquerdo (GC2, FCM2 e ADSC2). A FCM e a ADSC foram obtidas respectivamente, da medula óssea e tecido adiposo de cada aninal, ambos utilizados como implantes autólogos. Após 13 e 26 semanas, realizaram-se as biopsias de todos os grupos e imediatamente, faziam-se imprints dos fragmentos para visualização do marcador fluorescente nanocristal. Os fragmentos foram fixados em formol tamponado a 10%, para análise histológica, com as coloraçãoes de HE, luxol fast blue, tricrômio de Masson e imuno-histoquímica com os anticorpos neurofilamento (NF), S-100, FGF-2 e GDNF. Microscopicamente avaliou-se a presença de proliferação axonal, tecido conjuntivo, infiltrado inflamatório, células de Schwann, fatores de crescimento neurais, bainha de mielina, e degeneração walleriana. Para a análise histológica estabeleceram-se escores qualitativos e para a imuno-histoquímica realizou-se análise quantitativa com o programa Image J. Foi observada diminuição da degeneração walleriana, melhor reorganização fascicular, aumento do colágeno novo, início de formação de bainha de mielina, além de maior marcação do anticorpo NF nos grupos experimentais em relação ao GC. O grupo ADSC apresentou melhores resultados em relação aos demais, enfatizando a eficiência das ADSCs em relação à FCM e ao GC para a regeneração nervosa periférica. Porém, há a necessidade de um tempo maior para ocorrer completa regeneração do tecido nervoso periférico após lesão.

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Thanks to their adaptability and high efficiency compared to traditional carbon based surfactants, silicone surfactants are a success in many different applications, from pesticides to cosmetics, polyurethane foam, textile and car care products. In spite of those numerous applications, no analytical method existed for their trace determination in environmental samples and no data have been available regarding their environmental occurrence and fate. An analytical method for the trace analysis of trisiloxane surfactants in the aqueous environment was developed and validated. The method, based on liquid-liquid extraction and HPLC-MS/MS, reaches limits of quantification in the ng L-1 range and allows an individual quantification of every homologue of the targeted trisiloxane surfactant. The newly developed analytical method was applied to analyze 40 river water samples. The targeted trisiloxane surfactant was detected in 14 samples, between 1 ng L-1 and 100 ng L-1. The results showed that the studied trisiloxane surfactant does not ubiquitously occur in the aquatic environment in measurable concentrations, but can reach surface waters on a local scale. In order to assess the persistence of the trisiloxane surfactant in surface waters, its hydrolysis was studied in the lab, under various conditions (temperature, pH, and concentration). The half-lifes at pH 7 and 2 mg L-1 were found to be between 29 days and 55 days at 25°C and between 151 days and 289 days at 12°C. Taking only into account the hydrolysis, these results indicate that the trisiloxane surfactant could persist several weeks in surface waters. A degradation product of the trisiloxane surfactant was tentatively identified by high resolution mass spectrometry. When used as agricultural adjuvants, trisiloxane surfactants may reach the soil compartment and might further leach to ground water. The behavior of the trisiloxane surfactant on soil was therefore investigated to assess the possibility to reach ground water. With a sorption batch equilibrium method, distribution coefficients between water and soil (Kd, Koc, and Kclay) were estimated for two standard soils (loam and sandy loam) and for every homologue of the trisiloxane surfactant. The obtained values for Kd were between 15 L kg-1 and 135 L kg-1, indicating that the trisiloxane surfactant is only slightly mobile in soil. To further investigate the possibility of leaching to ground water after application on agricultural fields, the leaching in soil was simulated in the lab in a soil column. The experimental settings were designed to simulate a worst case scenario where the application of the trisiloxane surfactant is done on quartz sand and is immediately followed by a heavy rainfall. Even in these conditions, less than 0.01 % of the initially applied trisiloxane surfactant leached through 20 cm of quartz sand. Based on the Kd values and the results of the leaching in soil column, the studied trisiloxane surfactant is considered to be unlikely to leach to ground water after application as an agricultural adjuvant.

Various silicone elastomers have been evaluated for use in the prosthetic reconstruction of facial defects. Their strength, texture, flexibility, hardness, ease of preparation, pigment receptivity and retention, and their resistance to cleaning were compared and the data consulted when an elastomer was chosen to restore defects, improve aesthetics and reestablish the confidence of a selection of patients. Detailed case reports are provided, together with information on the adhesives or mechanical methods available for retaining the facial prosetheses. Cyanoacrylate adhesives for use on skin surfaces and as tissue adhesives have been studied in detail. A novel n-butyl 413 cyanoacrylate has been developed with a viscosity, haemostatic property and stability to make it particularly suitable for use in skin grafting and tissue repair. It has already been used with good results on patients with severe burns. An improved formulation, containing a fluorescent dye, can be precisely applied through a specially constructed foot-controlled dispenser illuminated by a fibre-optic supplying UV-light. Cyanoacrylates are already being used as tissue adhesives in place of the conventional but potentially disfiguring suture. The availability of improved, imperceptible adhesives and a precision applicator, which can be used in a modern operating theatre, will extend their effectiveness and satisfy some of the needs of Plastic, and Oral and Maxillo-Facial Surgeons. Portable applicators have potential use in battlefield and in veterinary surgery and overcome the imprecision characteristic of earlier methods.

Background: High-density silicone oils are newly developed long-term tamponade agents for the treatment of complicated retinal detachment in the inferior retina. Previous studies describe satisfying anatomical and functional results. In this study we examined the largest cohort so far for a 9-month follow-up and performed a comparison to conventional silicone oil. Methods: Our study documents results and adverse effects after vitreoretinal surgery and endotamponade with Densiron® 68 in 99 cases of complicated retinal detachment. A 9-month follow-up was performed. Data of 21 patients with intraocular conventional silicone oil tamponade in complicated retinal detachment were retrospectively analyzed and served as control. Results: Anatomical success was achieved in 78 of 89 eyes (87.6%) with completed follow-up; visual acuity did not change significantly (from mean preoperative logMAR 1.88 to postoperative logMAR 1.96 (p = 0.9). Compared to control a higher anatomical success but a similar number of adverse effects were observed with heavy silicone oil in vitreous. Nevertheless, patients who received Densiron 68 twice due to redetachment showed a significantly higher rate of intraocular inflammation with the tamponade agent in situ. Conclusion: Our results support the hypothesis of Densiron 68 as potent tamponade agent for complicated retinal detachment in the inferior retinal segments especially in eyes where a previous operation failed. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

A novel paste deposition process was developed to widen the range of possible materials and applications. This experimental process developed an increasingly complex series of additive manufacturing machines, resulting in new combinations of novel materials and deposition paths without sacrificing many of the design freedoms inherit in the craft process. The investigation made use of open-source software together with an approach to programming user originated infill geometries to form structural parts, differing from the somewhat automated processing by 'closed' commercial RP systems. A series of experimental trials were conducted to test a range of candidate materials and machines which might be suitable for the PDM process. The combination of process and materials were trailed and validated using a series of themed case studies including medical, food industry and jewellery. Some of the object created great interest and even, in the case of the jewellery items, won awards. Further evidence of the commercial validity was evidenced through a collaborative partnership resulting in the development of a commercial version of the experimental system called Newton3D. A number of exciting potential future directions having been opened up by this project including silicone fabrics, bio material deposition and inclusive software development for user originated infills and structures.

O núcleo metálico fundido (NMF), dentre outras funções, visa suportar a restauração que o sobrepõe. Muitas são as técnicas que podem ser utilizadas para a obtenção deste núcleo; o importante, porém, para manutenção da integridade dental, é a sua perfeita adaptação intra-radicular. Este trabalho apresenta um método para moldagem de condutos radiculares utilizando, como suporte intra-radicular, agulha hipodérmica. Foram realizados tratamentos endodônticos em 10 dentes humanos uniradiculares e, após o preparo, o conduto foi moldado (dupla impressão) com siliconas polimerizadas por condensação e adição, pela técnica indireta, utilizando dois tipos de suporte intra-radicular (pinjet e agulha hipodérmica). Foram obtidos 4 moldes de cada dente (interagindo material x técnica) totalizando 40 modelos, sobre os quais foram encerados os núcleos. Após a fundição, a adaptação dos núcleos foi analisada segundo dois métodos: radiográfico e microscópico. No primeiro, os dentes foram radiografados com os NMFs em posição e as imagens digitalizadas foram analisadas em computador (software ImageLab). Para avaliação microscópica, os dentes foram seccionados longitudinalmente, os núcleos foram adaptados no interior do canal e a adaptação foi verificada em microscópio de dupla coordenada, em que era calculada a porcentagem do conduto ocupada pelo NMF. Constatou-se que houve diferença estatisticamente significante (2 way ANOVA - Bonferroni - p<0.05) entre as médias dos valores de adaptação obtidos em função da técnica (agulha x pinjet) utilizando a silicona polimerizada por adição, nos dois métodos de avaliação. Não houve diferença estatisticamente significante em relação aos materiais de moldagem utilizados. Concluiu-se que a técnica utilizando agulha hipodérmica apresentou melhor fidelidade de reprodução permitindo melhor adaptação do NMF, quando utilizada a silicona polimerizada por adição. / Post and core aim to support the crown, being necessary a perfect intraradicular adaptation. There are several techniques that can be used to obtain cores, however, in order to maintain dental integrity, it is important to achieve a perfect intra-radicular adaptation. This study presents an inedited and innovator method for molding root canals using hypodermic needle as intra-radicular support. Endodontic treatment was done in 10 uniradicular human teeth and, after the preparation, root canals were molded (double print) with condensation cure silicone and addition cure silicone by indirect technique, using two types of intra-radicular supports (Pinjet and hypodermic needle). Four molds were obtained from each tooth (interacting material X technique) totalizing 40 models, on which the cores were polished. After fusion, the adaptation of cores was analyzed according to two methods: radiographic and microscopic. In the first, teeth were radiographed with the core in position and the digitalized images were analyzed through ImageLab software. For microscopic evaluation, teeth were longitudinally sectioned, the cores were adapted into root canals, and the adaptation was verified in microscope of double coordinate. The occupation percentage of core into root canal was calculated. A significant statistical difference (two-way ANOVA and Bonferroni\'s - p<0.05) was found between mean values of adaptation considering the molding technique (needle x pinjet) using the addition silicon in the two evaluated methods. There was no significant statistical difference regarding the utilized materials. It was concluded that the hypodermic needle technique had better fidelity of reproduction, permitting a good adaptation of cores, regardless of the material utilized.

Orientador: Fausto Viterbo / Resumo: O estudo avaliou o efeito da membrana de silicone no tratamento de área cruenta de ferimento. Método: O estudo experimental foi realizado com 30 ratos Wistar, machos, divididos igualmente em três grupos: no grupo GG a área cruenta foi tratada com gazes, no grupo GH com homoenxerto e no grupo GS com membrana de silicone. Após quatorze dias de pós-operatório, os animais foram sacrificados. Os atributos estudados foram a variação da massa corporal dos animais; o estudo histológico quantificado por análise morfométrica avaliando o número de neovasos, fibroblastos, fibras colágenas, leucócitos, monócitos; e a medida da espessura da área cruenta através de régua micrométrica. Os dados foram submetidos à análise estatística. Resultados: Não houve diferença significativa entre as massas dos animais. Observou-se um predomínio de neovasos, fibroblastos e a espessura de área cruenta nos animais do grupo GS. Houve predomínio de leucócitos e monócitos nos animais do grupo GH. Também foi observado que não houve diferença significativa entre os grupos quanto às fibras colágenas. Conclusão: A membrana de silicone proporcionou tecido de granulação com maior número de neovasos, fibroblastos e maior espessura. / Abstract: The purpose of this study was to evaluate effects of the silicone membrane on treatment of wound healing base. Methods: The experimental study was with thirty Wistar male rats equally divided into three groups. Group GG the would healing base was treatment with rayon gauz, group GH with homograft and group GS with silicone membrane. The animals were sacrificed 14 postoperative day. This study evaluated weigh of rats; histological and morphometric analysis of the number of neovessels, fibroblasts, collagen fibers, leucocytes and monocytes; and measurement of wound healing base thickness was done with micrometer straight edge . The data were submitted to statistical analysis. Results: The weight of rats was similar among groups. The analysis showed considerable increased number of neovessels, fibroblasts and the measurement of would healing base thickness on the group GS; considerable increased number of leucocytes and height increased number of monocytes on the group GH. Similar pattern was observed in number of collagen fibers among three groups. Conclusion: The silicone membrane supportered wound healing base with considerable increased number of neovessels, fibroblasts and enlarging measurement of thickness. / Mestre

This thesis investigates the feasibility of loading silicone hydrogel (SiHy) contact lenses with two different hydrophobic therapeutics, latanoprost and DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine), for treatment of glaucoma and hyperemia respectively. The two methods of loading were 1) thermal loading in an aqueous medium and 2) convective loading in a solution of n-propanol. Dailies Total1® lenses prepared in this manner were tested for their loading and their release into artificial tears. Continuous release over 1-4 days at therapeutic levels is achievable from thermal loading of DMPC, convective loading of DMPC, and convective loading of latanoprost. The DMPC loading processes can be naturally integrated into standard manufacturing lines for Dailies Total1®. Both DMPC and latanoprost release at rates proportional to the amount loaded into a contact lens. Latanoprost loads into a contact lens strictly proportionally to the loading concentration and the time of loading. The convective loading step represents a significant improvement on both the time of loading (reduced from days to minutes) and the loading capacity of silicone hydrogel contact lenses. This thesis also compares the loading and release of latanoprost in the convective loading procedure using the SiHy contact lenses of Acuvue Advance® (Johnson & Johnson Vision Care, Jacksonville, FL) , Air Optix® (Alcon, Copenhagen, Denmark), Biofinity® (CooperVision), PureVision® (Bausch & Lomb), and Dailies Total1® (Alcon), and the polyHEMA lens, SofLens 38® (Bausch & Lomb), finding that silicone hydrogels load an order of magnitude more drug than the polyHEMA lens and release into artificial tears for an order of magnitude longer. Overall, these experiments provide a quantitative understanding of the dynamics of loading and release for both DMPC and latanoprost.

Textile processing methods such as conventional exhaustion dyeing, pre-treatments and printing consume high amounts of water and use partly toxic and hazardous chemicals which are non-degradable. These chemicals (e.g. excess amount of dye, additives and catalysts) remain partially in the waste-water which is drained out and ends up polluting the environment. The supercritical carbon dioxide dyeing technology presents an eco-friendly and water-free method with reduced use of chemicals and energy. The benefits of such technology are currently not overcoming the relative high investment costs which impede its full implementation into the textile industry. This study presents an approach to extent the application of the eco-friendly supercritical carbon dioxide technology. It combines the well-studied supercritical carbon dioxide dyeing process for polyester with the functionalisation process to obtain water repellent surface properties. As water repellent (substance) environmentally benign silicones are used. Results showed that the simultaneous dyeing and functionalisation process was feasible assessed by the compatibility of the dye and silicone in the system. Silicone and dye did not interfere in each other’s functionality (colour strength and water contact angle). Further the process temperature and silicone molecular weight showed no influence on the colour strength of the fabric whereas the water contact angle (water repellence) increased with increasing temperature. The resulting polyester fabric showed acceptable colour strength yet did not obtain sufficient water repellent properties despite the increase in water contact angle of the treated samples to the untreated reference sample. The poor water repellence is suggested to be caused by the hydrophobic functional groups of the silicones oriented towards each other rather than toward the outer fabric surface. Overall the thesis is promoting research which combines eco-friendly technologies including environmental benign chemicals for the textile industry. Silicones are widely used in textile processing not only as water repellents, but also as anti-foaming agents, lubricants and softeners. Therefore a water-free and eco-friendly application method can benefit a wide range of finishing processes.