O objetivo foi avaliar, in vitro, a influência da utilização do cianoacrilato (Dermabond®) e de diferentes tratamentos da dentina intra-radicular na adesividade da resina composta fotopolimerizável utilizadas no reforço de raízes fragilizadas por meio de teste de tração. Foram utilizados 40 raízes de caninos superiores humanos com apenas um canal e sem curvatura acentuada que foram padronizados no comprimento mínimo de 15mm. As raízes foram submetidas a fragilização das paredes internas com o auxílio de um paralelômetro e em seguida foi realizado o tratamento endodôntico por meio de instrumentos manuais, finalizando com diâmetro cirúrgico equivalente à lima 60. A obturação foi realizada pela técnica híbrida modificada de McSpadden, utilizando-se o cimento obturador AH Plus®. Estas raízes foram divididas em 4 grupos (n=10) de acordo com a realização ou não do toalete e condicionamento ácido, como também do agente adesivo utilizado: Grupo I - Dentes obturados seguidos de toalete da cavidade e condicionamento ácido, com aplicação de adesivo dentinário; Grupo II - Dentes obturados seguidos de toalete da cavidade e condicionamento ácido, com uso de cianoacrilato na parede dentinária; Grupo III - Dente obturado sem toalete da cavidade e sem condicionamento ácido, com aplicação de adesivo na parede dentinária; Grupo IV - Dente obturado sem toalete da cavidade e sem condicionamento ácido, com uso de cianoacrilato na parede dentinária. As raízes de todos os grupos foram reforçadas com resina composta fotopolimerizável Z100®, com o auxílio de pinos fototransmissores e receberam pinos rosqueáveis de metal, cimentados com cimento resinoso Relyx®. Na sequência as raízes foram submetidas a teste de tração. Os dados experimentais consistiram em valores numéricos de resistência à tração expressos em MegaPascal (MPa), provenientes dos resultados da tensão máxima necessária para o deslocamento dos núcleos de preenchimentos (resina fotopolimerizável + pino metálico). Os resultados foram submetidos à análise estatística com nível de significância de 5% (&alpha;=0,05), apresentando distribuição normal. Dessa forma, foi realizado teste paramétrico de Análise de Variância (one-Way ANOVA). A análise de variância indicou haver diferença significante entre os grupos (P<0,05). O teste Tukey de comparações múltiplas evidenciou que os grupos II e IV são semelhantes entre si (p>0,05) e apresentam os menores valores de resistência à tração, com diferença estatística extremamente significante quando comparado aos grupos I e III (p<0,001), e a comparação entre os grupos I e III acusou diferença significante (p<0,01), sendo o grupo I aquele que necessitou de maior força de tração para deslocar o núcleo de preenchimento. / The aim of this study was to assess in vitro, using a tensile bond strength test, the influence of 2-octyl-cyanoacrylate (Dermabond®) and different intraradicular dentin treatments on the adhesiveness of a light-cured composite resin used for the reinforcement of weakened roots. For this purpose were used 40 roots human maxillary canines with a single canal and without accentuated root curvature, which had their minimum length standardized to 15 mm. The internal root walls were weakened with the aid of parallelometer. Next, the endodontic treatment was performed with hand files until reaching a surgical diameter corresponding to a size 60 file. Root canal filling was performed according to the hybrid modified McSpadden technique and using AH Plus® sealer. The roots were assigned to four groups (n=10) depending on whether or not cleaning of cavity and acid etching were performed as well as the type of adhesive agent employed: Group I - Root canal filling followed by cleaning of cavity, acid etching and adhesive system application on the dentinal walls; Group II - Root canal filling followed by cleaning of cavity, acid etching and cyanoacrylate application on the dentinal walls; Group III - Root canal filling without cleaning of cavity or acid etching, and with adhesive system application on the dentinal walls; Group IV - Root canal filling without cleaning of cavity or acid etching, and with cyanoacrylate application on the dentinal walls. In all groups, the roots were reinforced with Z100® light-cured composite resin and light-transmitting posts, and received threaded metal posts cemented with Relyx® resin-based cement. Following reinforcement, the roots were subjected to tensile bond strength testing. The experimental data consisted of the maximum tensile strength values, expressed in MegaPascal (MPa), required for dislodging the post-core system (light-cured resin + metal post). Data presented normal distribution and were subjected to statistical analysis by one-way analysis of variance (ANOVA) parametric test at a 5% significance level. There was statistically significant difference among the groups (p<0.05). Tukey&prime;s multiple-comparison test revealed that Groups II and IV were similar (p>0.05) and presented the lowest tensile bond strength values, with an extremely significant statistical difference when compared with Groups I and III (p<0.001). Comparison between Groups I and III showed a significant difference (p<0.01), with Group I requiring the highest tensile strength to dislodge the post-core system.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-06T17:32:29Z No. of bitstreams: 1 rodrigofalcisantos.pdf: 3181366 bytes, checksum: 26ae7d9a4c2057c4eaf0d4de25c69495 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-08T14:40:37Z (GMT) No. of bitstreams: 1 rodrigofalcisantos.pdf: 3181366 bytes, checksum: 26ae7d9a4c2057c4eaf0d4de25c69495 (MD5) / Made available in DSpace on 2016-06-08T14:40:37Z (GMT). No. of bitstreams: 1 rodrigofalcisantos.pdf: 3181366 bytes, checksum: 26ae7d9a4c2057c4eaf0d4de25c69495 (MD5) Previous issue date: 2013-03-21 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Este ensaio pré-clínico se propôs avaliar e comparar o volume ósseo na interface enxerto/leito receptor, utilizando o etil-cianoacrilato (Super Bonder Flex Gel®) e parafusos de titânio como agentes de fixação na incorporação de enxertos ósseos, verificado por meio de microtomografia computadorizada. Para tal, utilizou-se 12 ratos, da espécie Rattus novergicos albinus, (Wistar), machos adultos com aproximadamente três meses de idade. Os animais foram aleatoriamente divididos em dois grupos de seis, com um grupo controle (grupo Parafuso Titânio – PT), no qual foi utilizado um parafuso de fixação interna rígida para estabilização do enxerto, e um grupo experimental (grupo Super Bonder Flex Gel® - SB) , no qual foi aplicado o adesivo para estabilizar o enxerto ósseo. O procedimento foi realizado sob anestesia geral, removendo-se um enxerto em bloco do osso parietal esquerdo e fixando-o no osso parietal direito na calvária dos animais. Após 30 dias de cirurgia os 12 animais foram submetidos à eutanásia e o material enxertado foi submetido à análise microtomográfica. O teste U de Mann Whitney, não mostrou diferença estatisticamente significativa entre os parâmetros avaliados (volume total-TV, volume ósseo-BV, fração do volume-BV/TV, espessura trabecular-Tb.Th, distância intertrabecular-TB.Sp e número de trabéculas-Tb.N) em ambos os grupos, com exceção da distância entre as trabéculas (Tb.Sp). O grupo SB apresentou uma Tb.Sb significativamente maior (p=0,015). Desta forma pode-se concluir que o exame de microtomografia computadorizada foi capaz de detectar formações de tecido ósseo mineralizado na interface enxerto/leito receptor após 30 dias do experimento. Além disso, o etil-cianoacrilato foi tão eficiente quanto o parafuso de titânio na estabilização e incorporação do enxerto ósseo na calvária de ratos, tanto em relação aos parâmetros volumétricos, quanto em relação aos parâmetros de densidade óssea. / This preclinical trial was developed with the aim of evaluating and comparing the bone volume in the interface bone / graft, using ethyl-cyanoacrylate (Super Bonder Flex Gel ®) and titanium screws as fixing agents in bone graft incorporation, evaluated by computed microtomography. To verify the efficiency of the tested product, 12 adult male rats of the species Rattus novergicos albinus (Wistar) of approximately three months of age were randomly divided into two groups of six rats each. In the control group (PT), a screw internal fixation was used to stabilize the graft. In the experimental group (SB) an adhesive of ethyl- cyanoacrylate was used. Under general anesthesial a block graft was removed from the left parietal bone and fixed on the right parietal bone, in the calvaria of the animal. Thirty days after the surgery, all animals were euthanized and the grafted material analyzed by computed microtomography. The Mann Whitney U test did not show any statistically significant difference between the proposed parameters (Total volume – TV, Bone volume – BV, Bone volume fraction – BV/TV, Trabecular thickness – Tb.Th, Trabecular separation – Tb.Sp and Trabecular number – Tb.N) in both groups, except for the Trabecular separation (Tb.Sp). The SB group presented a Tb.Sb higher than the PT group (p = 0.015) with statistical significance. Therefore, was possible to conclude that the computed microtomography test was able to detect mineralized bone tissue formations in the interface bone / graft after 30 days. Also the volumetric parameters and the parameters of bone density for ethyl-cyanoacrylate was as efficient as the titanium screw in bone graft incorporation in rat calvaria.

For the past several decades, challenges in the detection and collection of latent prints exposed to harsh environmental conditions have inspired research in pretreatment methods prior to the application of chemical, physical, or optical-based enhancement techniques. Some of the difficulties associated with processing degraded latent prints are attributed to dehydration, alterations in chemical composition, and physical disturbance of ridge detail. This study seeks to investigate the effectiveness of humidity, cyanoacrylate fuming method (CFM), and a reflected ultraviolet imaging system (RUVIS) on the detection and collection of aged latent palmprints. Prints were exposed to air flow and ultraviolet (UV) light for a period of 0 to 28 days, and subsequently treated with either cool or warm humidity and CFM. RUVIS was then utilized to detect and capture friction ridge detail after each treatment step. Improvements in RUVIS detection between treatments were evaluated based on four response factors: minutiae count, percent print recovery, ridge thickness and contrast. By measuring these factors, each latent print photograph was able to be converted to quantifiable data to facilitate statistical analysis of potential differences or improvements between treatments. The results demonstrate that the application of 80% relative humidity successfully revived aged latent palmprints across all factors. The combined effect of humidity followed v by CFM treatment and RUVIS detection was greatest for minutiae count and ridge thickness, while percent print recovery and contrast demonstrated more modest improvements when compared to control prints. Additionally, cool temperature treatments outperformed warm temperature treatments across all factors except contrast. The data therefore suggest that to achieve print rejuvenation and overall improvements in RUVIS detection, combined cool humidity and CFM is more effective than humidity alone. The data also indicate a potential correlation between temperature treatments and latent print age. Warm humidity combined with CFM appeared to best enhance RUVIS images on fresher prints of a few days to one week old, while cool humidity and CFM appeared to maximally enhance RUVIS images on prints of several weeks old.

Titanium has been widely used for dental implants, and in particular, roughened titanium surfaces have provided a means for increasing bone apposition and strengthening the implant-to-bone interface. Finding a way to further increase osseointegration is important because there is a significant clinical benefit to patients if a stable anchor can be established instead of anchoring orthodontic hardware to the molars. In this study, the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on the ability of temporary anchorage devices (TADs) to osseointegrate was investigated. The temporary anchorage devices (TADs) used in this study were manufactured from commercially pure titanium and divided into 2 types of treatments: (1) sandblasted and acid-etched (i.e. the control) and (2) sandblasted and acid-etched treated with Medtronic INFUSE® Bone Graft (recombinant human bone morphogenetic protein-2 placed on an absorbable collagen sponge). The implants were placed on the cranial bones of 10 adult male Sprague-Dawley rats. The rats were euthanized by carbon dioxide asphyxiation 6 weeks following surgery for histological examination and biomechanical testing. The results from visual inspection and biomechanical testing showed that the sandblasted and acid-etched TADs treated with rhBMP-2 promoted better osseointegration than TADs that were only sandblasted and acid-etched. Specifically, surface modified TADs treated with rhBMP-2 on bottom showed an increased surface coverage by bone and an increase in the adhesion strength at the TAD-to-bone interface.

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.

Made available in DSpace on 2016-04-28T20:18:31Z (GMT). No. of bitstreams: 1 2008 - Jose Luis Acceta.pdf: 1494804 bytes, checksum: 4db4aa22a40640a9df16fa4956f3db06 (MD5) Previous issue date: 2008-07-03 / This work?s objective was to evaluate the occlusion?s viability of the bronchial stump by use of cyanoacrylate, verifying your efficacy and velocity of adhesion, and after-surgery animals recovery. Fifteen dogs, without defined races, males and females, adults were utilized and submited to the partial lobectomy (after traumatism), and the bit extremity was full-filed with cyanoacrylate. The clinical evolution was observed on the 15 subsequent days, by verifying the breath pattern, blood presence and seroma and air in thoracic cavity. The dogs stay housed during 15 days; then the sucture points were take out and the animals go home. / O objetivo deste trabalho foi avaliar clinicamente a viabilidade da oclus?o do coto br?nquico com utililiza??o de adesivo a base de cianoacrilato ap?s lobectomia. Foram utilizados 15 c?es, SRD, machos e f?meas, acima de dois anos de idade, atendidos na Cl?nica Veterin?ria S?o Francisco e no Hospital das Cl?nicas Veterin?rias (HCV) da UNIPLI em emerg?ncia, com les?es pulmonares cujo tratamento cir?rgico necessitou lobectomia pulmonar. Realizou-se a lobectomia completa do lobo pulmonar comprometido, e a extremidade do coto foi preenchida com adesivo ? base de cianoacrilato. A evolu??o cl?nica foi avaliada nos 15 dias subsequentes, atrav?s da verifica??o do padr?o respirat?rio e presen?a de sangue, seroma ou ar na cavidade tor?cica. Os c?es ficaram internados por 15 dias, quando ent?o os pontos foram retirados e os animais receberam alta. O adesivo de cianoacrilato mostrou-se clinicamente eficiente na execu??o e manuten??o da pneumostasia de coto bronquial remanescente em lobectomias totais.

A zidovudina (AZT), fármaco antirretroviral utilizado no tratamento da AIDS, apresenta biodisponibilidade oral em torno de 60% e seu uso prolongado pode ocasionar efeitos tóxicos e tolerância ao tratamento. A lamivudina (3TC), apesar de demonstrar menor citotoxicidade e menor resistência viral, é considerada também menos potente. A associação entre os dois fármacos é recomendável em função da boa resposta terapêutica e maior adesão ao tratamento. As nanopartículas são uma alternativa para melhorar a biodisponibilidade e o transporte de fármacos sobretudo através da BHE. Nesse sentido, as nanopartículas poliméricas de poli (n-butil cianoacrilato) (PBCA) apresentam grande potencial para melhoria das características farmacêuticas, além de possibilitar resultados terapêuticos mais eficazes por meio da modificação de sua superfície, direcionando o fármaco ao sítio alvo. Diante do exposto, foram desenvolvidas nanopartículas de PBCA contendo a associação lamivudina e zidovudina (3TC/AZT) revestidas com polissorbato 80 (Ps80). As nanopartículas obtidas foram caracterizadas e apresentaram resultados coerentes aos encontrados na literatura. Após a encapsulação dos fármacos e o revestimento com Ps80, notou-se um aumento no diâmetro médio e o potencial Zeta foi próximo de zero. Esses resultados juntamente com a análise de SAXS comprovam o revestimento das nanopartículas de PBCA. Os dados de DSC e TG/DTG mostram que a encapsulação foi eficiente para a estabilização térmica dos fármacos. Foi desenvolvido e validado o método analítico por CLAE, a fim de determinar a eficiência de encapsulação. A validação do método analítico para quantificação simultânea do 3TC e AZT, tanto nas nanopartículas de PBCA quanto nas nanopartículas revestidas, apresentou linearidade, especificidade, precisão e exatidão adequadas de acordo com as normativas. A porcentagem de encapsulação dos fármacos foi igual a 44,45% e 30,44%. As nanopartículas de PBCA e PBCAPs80, em concentrações abaixo de 100 &#181;g/mL, apresentaram viabilidade celular superior a 70% em células Caco-2, comprovando que o sistema apresenta baixa citotoxicidade, o que representa uma alternativa promissora para a encapsulação de fármacos antirretrovirais e consequente progresso no tratamento da AIDS. / Zidovudine (AZT), which is an anti-retroviral drug used in the treatment of AIDS, has oral bioavailability around 60% and its prolonged use can cause toxic effects and tolerance to the treatment. Lamivudine (3TC), although it has lower cytotoxicity and lower viral resistance, is also considered less potent. The association between these two drugs is recommended based on the good therapeutic response and greater adherence to treatment. Nanoparticles are an alternative to improve the bioavailability and the transport of drugs, particularly through the BBB. Thus, the polymeric nanoparticles of poly (n-butyl cyanoacrylate) (PBCA) have great potential for improving the pharmaceutical characteristics, besides enabling more effective therapeutic results through the modification of its surface, directing the drug to the target site. That being said, PBCA nanoparticles were developed containing the association of lamivudine and zidovudine (3TC/AZT) coated with polysorbate 80 (Ps80). Nanoparticles obtained were characterized and presented coherent results when compared to those found in the literature. After the encapsulation of pharmaceuticals and Ps80 coating, it was noted an increase in the average diameter and Zeta potential was close to zero. These results along with the SAXS analysis proved the coating of the PBCA nanoparticles. The data of DSC and TG/DTG show that encapsulation was efficient for thermal stabilization of pharmaceuticals. An analytical method by HPLC was developed and validated to determine the efficiency of encapsulation. The validation of the analytical method for simultaneous quantification of 3TC and AZT, in both the PBCA nanoparticles and coated nanoparticles, presented as in linearity, specificity, precision and accuracy according to the regulations. The percentage of drug encapsulation was equal to 44.45% and 30.44%. The nanoparticles of PBCA and PBCA-Ps80, at concentrations below 100 &#181;g/ml, presented cell viability greater than 70% in Caco-2 cells, proving that the system has low cytotoxicity, which represents a promising alternative for the encapsulation of antiretroviral drugs and consequent progress in AIDS treatment.

L’embolisation vasculaire est un traitement peu invasif utilisé pour éliminer ou interrompre de façon sélective les apports vasculaires à des régions spécifiques du corps. Une technique consiste en l’introduction d’un microcathéter dans le vaisseau sanguin cible et à administrer un agent embolique qui réagit au contact du sang. Les colles emboliques à base de cyanoacrylate sont les principaux agents liquides utilisés pour l’embolisation à cause de leur faible viscosité, leur bonne capacité de pénétration et leur faible toxicité tissulaire. Pour permettre sa détection après injection, la colle est mélangée à un agent de contraste radio-opaque telle que l’huile iodée Lipiodol®. Bien que la technique soit couramment utilisée, il existe peu de données sur la dynamique du processus d’injection au sein de flux sanguins complexes ou sur la cinétique de polymérisation du mélange colle-Lipiodol. Par conséquent, une occlusion sans danger est difficile à réaliser, même entre les mains de radiologues expérimentés. Le principal objectif de la thèse est d’étudier de façon quantitative les propriétés physiques et la cinétique de polymérisation des colles cyanoacrylates mélangées au Lipiodol dans différentes proportions. Nous avons conçu un nouveau dispositif expérimental pour caractériser le processus de polymérisation d’un mélange colle/Lipiodol en contact avec une solution ionique ou protéinée. Les résultats montrent un processus de polymérisation rapide à l’interface entre la colle et le substrat, suivi par la proagation d’un front de polymérisation dans le volume de préparation de colle. Les constantes de temps des processus dépendent des compositions de la solution et du mélange de colle. Un autre objectif est d’analyser le processus d’embolisation dynamique. Un modèle in vitro du processus d’injection est utilisé pour étudier en premier lieu la formation de goutte entre deux flux immiscibles et qui ne réagissent pas entre eux. L’injection d’une préparation de colle dans une solution ionique en écoulement est ensuite réalisée pour montrer l’influence conjointe de la polymérisation et de l’hydrodynamique. C’est la première fois qu’une telle caractérisation exhaustive de colles emboliques à base de cyanoacrylate est obtenue. Les résultats peuvent apporter des informations cruciales aux radiologues interventionnels, ce qui les aidera à comprendre et contrôler le comportement de la colle après injection afin d’accomplir une oblitération permanente des vaisseaux en toute sécurité. / Vascular embolization is a minimally invasive treatment used to selectively eliminate or stop the vascular supply to specific body areas. One technique consists of navigating a microcatheter into the targeted blood vessel and injecting an embolic agent which reacts in contact with blood. Cyanoacrylate-based embolic glues are the main liquid adhesives used for vascular embolization owing to their low viscosity, good penetration ability and low tissue toxicity. To enable its detection once injected, the glue is mixed with a radio-opaque contrast agent such as the Lipiodol iodized oil. Although the technique is commonly used, there is very little information on the dynamics of the injection process in complex blood flows or on the polymerization kinetics of the glue-Lipiodol mixture. Consequently, safe occlusion is difficult to achieve, even in the hands of experienced radiologists. The main objective of the thesis is to quantitatively investigate the physical properties and polymerization kinetics of cyanoacrylate glues mixed with Lipiodol in different proportions. We have designed a new experimental setup to characterize the polymerization process of a glue/Lipiodol mixture on contact with an ionic or proteinaceous solution. We find that there is a fast polymerization process at the interface between the glue and the substrate, followed by the propagation of a polymerization front in the glue mixture volume. The time constants of the processes depend on the solution and glue mixture compositions. Another objective is to analyze the dynamic embolization process. An in vitro model of the injection process is used to first investigate the drop formation between two non-reacting immiscible flows. The injection of a glue mixture into a flowing ionic solution is then performed to show the joint influence of polymerization and hydrodynamics. It is the first time that such comprehensive characterization of cyanoacrylate-based embolic glues is acquired. The results can provide crucial information to interventional radiologists, that will help them understand and control the glue behavior after injection to achieve a safe and permanent obliteration of the vessels.

A zidovudina (AZT), fármaco antirretroviral utilizado no tratamento da AIDS, apresenta biodisponibilidade oral em torno de 60% e seu uso prolongado pode ocasionar efeitos tóxicos e tolerância ao tratamento. A lamivudina (3TC), apesar de demonstrar menor citotoxicidade e menor resistência viral, é considerada também menos potente. A associação entre os dois fármacos é recomendável em função da boa resposta terapêutica e maior adesão ao tratamento. As nanopartículas são uma alternativa para melhorar a biodisponibilidade e o transporte de fármacos sobretudo através da BHE. Nesse sentido, as nanopartículas poliméricas de poli (n-butil cianoacrilato) (PBCA) apresentam grande potencial para melhoria das características farmacêuticas, além de possibilitar resultados terapêuticos mais eficazes por meio da modificação de sua superfície, direcionando o fármaco ao sítio alvo. Diante do exposto, foram desenvolvidas nanopartículas de PBCA contendo a associação lamivudina e zidovudina (3TC/AZT) revestidas com polissorbato 80 (Ps80). As nanopartículas obtidas foram caracterizadas e apresentaram resultados coerentes aos encontrados na literatura. Após a encapsulação dos fármacos e o revestimento com Ps80, notou-se um aumento no diâmetro médio e o potencial Zeta foi próximo de zero. Esses resultados juntamente com a análise de SAXS comprovam o revestimento das nanopartículas de PBCA. Os dados de DSC e TG/DTG mostram que a encapsulação foi eficiente para a estabilização térmica dos fármacos. Foi desenvolvido e validado o método analítico por CLAE, a fim de determinar a eficiência de encapsulação. A validação do método analítico para quantificação simultânea do 3TC e AZT, tanto nas nanopartículas de PBCA quanto nas nanopartículas revestidas, apresentou linearidade, especificidade, precisão e exatidão adequadas de acordo com as normativas. A porcentagem de encapsulação dos fármacos foi igual a 44,45% e 30,44%. As nanopartículas de PBCA e PBCAPs80, em concentrações abaixo de 100 &#181;g/mL, apresentaram viabilidade celular superior a 70% em células Caco-2, comprovando que o sistema apresenta baixa citotoxicidade, o que representa uma alternativa promissora para a encapsulação de fármacos antirretrovirais e consequente progresso no tratamento da AIDS. / Zidovudine (AZT), which is an anti-retroviral drug used in the treatment of AIDS, has oral bioavailability around 60% and its prolonged use can cause toxic effects and tolerance to the treatment. Lamivudine (3TC), although it has lower cytotoxicity and lower viral resistance, is also considered less potent. The association between these two drugs is recommended based on the good therapeutic response and greater adherence to treatment. Nanoparticles are an alternative to improve the bioavailability and the transport of drugs, particularly through the BBB. Thus, the polymeric nanoparticles of poly (n-butyl cyanoacrylate) (PBCA) have great potential for improving the pharmaceutical characteristics, besides enabling more effective therapeutic results through the modification of its surface, directing the drug to the target site. That being said, PBCA nanoparticles were developed containing the association of lamivudine and zidovudine (3TC/AZT) coated with polysorbate 80 (Ps80). Nanoparticles obtained were characterized and presented coherent results when compared to those found in the literature. After the encapsulation of pharmaceuticals and Ps80 coating, it was noted an increase in the average diameter and Zeta potential was close to zero. These results along with the SAXS analysis proved the coating of the PBCA nanoparticles. The data of DSC and TG/DTG show that encapsulation was efficient for thermal stabilization of pharmaceuticals. An analytical method by HPLC was developed and validated to determine the efficiency of encapsulation. The validation of the analytical method for simultaneous quantification of 3TC and AZT, in both the PBCA nanoparticles and coated nanoparticles, presented as in linearity, specificity, precision and accuracy according to the regulations. The percentage of drug encapsulation was equal to 44.45% and 30.44%. The nanoparticles of PBCA and PBCA-Ps80, at concentrations below 100 &#181;g/ml, presented cell viability greater than 70% in Caco-2 cells, proving that the system has low cytotoxicity, which represents a promising alternative for the encapsulation of antiretroviral drugs and consequent progress in AIDS treatment.

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. / Loctite UK