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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efforts to improve latent fingerprint impression processing using fluorescent and colored superglues

Costley, Destiny 22 January 2016 (has links)
The use of cyanoacrylate (CA) as a fuming technique for the development of latent friction ridge skin impressions has been widespread for decades within the forensic lab as well as in the field at crime scenes. Important features of processing latent print impressions using this method include that it makes visible latent print impressions that for the most part cannot be seen with the unaided eye and it preserves latent print impressions for future processing/examination. The superglue fumes "fix" the latent print impression to the substrate making it difficult to wipe away, thereby decreasing the chances of destruction during packaging at the scene, transportation, and processing in the lab. One of the disadvantages to this technique is the lack of contrast between the white polymers that are formed on the latent print impression residue and light colored backgrounds on which the latent print impression may be present. Attempts were made to develop a one-step cyanoacrylate fuming method that would enhance visualization of latent print impressions on light colored backgrounds without the need for an alternative light source, dye staining, or powdering. Latent print impressions were applied to black and white ceramic tiles, white painted wood and white/translucent textured plastic. Protein and hemoglobin stains, commercial colorants, sublimation dyes, hair dye, and printer ink were added to ethyl-CA in an attempt to create a co-polymerization process of the vaporized cyanoacrylate monomers and colorant molecules on latent print residue. Fuming was also attempted using pre-colored commercial glues with the assumption that the attached CA polymers on the latent print impression residue would retain their original color properties. None of these methods proved successful. The practical use of a new fluorescent CA, Lumicyano^TM, was also examined. Following fuming, an ALS is utilized for the excitation of the developed latent print impressions using this technique. Strong fluorescence could not be observed on all substrates. In this particular study, fuming with traditional CA followed by the application of powder or dye stains to latent print impressions currently appears to be the most efficient technique for latent print enhancement on the white or light colored substrates used in this study.
2

Kyanoakrylátové lepidlo v průmyslu / Cyanoacrylate adhesives in industry

Novák, Libor January 2016 (has links)
The diploma thesis is processed as an experimental verification of properties of cyanoacrylate adhesives Loctite and SikaLock. The experiment compares properties of mentioned adhesives on ten different materials. These Materials were glued to the overlap joint. After bonding one part of samples were left usual conditions and the second part was put into the kataplasma, where the samples were exposed extreme conditions (high wetness and temperature). The next step was a test for shear stress. Measured values were recorded in graphs, for each pasted material.
3

Submicron Structures, Electrospinning and Filters

Bhargava, Sphurti 02 October 2007 (has links)
No description available.
4

Comparison of conjunctival pedicle flap to corneal adhesion achieved by Tisseel® fibrin glue, ethyl cyanoacrylate adhesive, ReSure® hydrogel sealant, and conventional suturing with 8-0 VICRYL® suture

VerHulst, Elodie Marie 09 February 2023 (has links)
Background: Conjunctival pedicle flaps are one of the most frequently employed surgical interventions used to address a variety of sight threatening corneal diseases in veterinary ophthalmic practice. Securing the conjunctiva to the cornea is typically achieved through suturing, which is technically challenging and can result in prolonged surgical times, increased corneal edema, increased scar tissue, foreign body reaction, suture abscess and dehiscence. In human ophthalmology, a number of sutureless techniques to affix ocular tissues are being explored. Specifically, these approaches include synthetic tissue adhesives, bioadhesives, and hydrogel sealants. The proposed advantages of adhesives over suture, include reduced operative times, watertight seals, decreased foreign-body sensation and inflammation, faster healing times and tissue regeneration with original architecture restoration. Objective. To evaluate the maximum tensile force a conjunctival pedicle flap is able to withstand with respect to different fixation methods, i.e., Tisseel® fibrin glue, ethyl cyanoacrylate adhesive, ReSure® hydrogel sealant, or 8-0 VICRYL suture. Animals Studied. Ex-vivo porcine globes Procedures. Following a 500-micron restricted depth lamellar keratectomy, conjunctival pedicle flaps were dissected and secured to corneal defects with either the bioadhesive Tisseel®, or the synthetic adhesives ReSure®, ethyl cyanoacrylate, or 8-0 VICRYL® suture. Harvested corneoconjunctival flap interfaces were clamped to an accelerometer and potentiometer device, and loaded under video surveillance until the point of failure. Peak load at failure was determined for each test and used to compare between sample types. Results. 40 flaps underwent tensile force testing, with 6 being omitted for dehiscence prior to tensile testing. Of the 34 tests included in analysis, 10 conjunctival flaps were secured with suture, 10 with cyanoacrylate, 8 with ReSure® hydrogel sealant, and 6 with Tisseel® fibrin glue. A significant increase in maximum withstood tensile force was recorded between sutured flap fixation when compared with cyanoacrylate glue (p=0.02474), ReSure® hydrogel sealant (p= 0.00000), and Tisseel® fibrin glue (p= 0.00002). Cyanoacrylate fixation was significantly stronger when compared with ReSure® hydrogel sealant and Tisseel fibrin glue (p=0.01194 and 0.01798 respectively). There was no significant difference in adhesion strength between ReSure® hydrogel sealant and Tisseel® fibrin glue (p=0.95675). Conclusions. Conjunctival pedicle flap fixation using 8-0 VICRYL® suture fixation was able to withstand significantly greater maximum tensile force application in comparison with the ReSure®, Tisseel®, or cyanoacrylate adhesives. / Master of Science / Conjunctival pedicle flaps are one of the most frequently employed surgical interventions to address sight threatening corneal disorders in companion animals. Due to its redundant nature and close proximity to the corneal surface, conjunctival tissue is readily available for grafting to the cornea. It is surgically dissected to appropriate size and repositioned over the corneal defect where it effectively aids in healing through direct provision of structural support and indirectly via its rich blood supply. Securing the conjunctiva to cornea is typically achieved through suturing, which is technically challenging and can result in prolonged surgical times, increased corneal edema, increased scar tissue, foreign body reaction, abscess and dehiscence. In human ophthalmology, a number of sutureless techniques to affix ocular tissues are being explored. Specifically, these approaches include synthetic tissue adhesives, bioadhesives, and hydrogel sealants. The proposed advantages of tissue adhesives over suture, include reduced operation times, watertight closures, decreased foreign-body reaction and inflammatory response, faster healing times and increased ability to induce regeneration of the original tissue architecture. The purpose of this study was to evaluate the maximum tensile force a corneoconjunctial pedicle flap is able to withstand with respect to four different fixation methods, 40 ex-vivo porcine globes underwent conjunctival pedicle flap procedures. Each pedicle flap was secured to cornea with either 8-0 Vicryl® suture, Tisseel®, ethyl cyanoacrylate, or ReSure®. After harvesting from the globe, the corneoconjunctival unions were clamped to an accelerometer and potentiometer device, and loaded under video surveillance until the point of failure. The peak load was determined for each test and used to compare between sample types.
5

Synthèse de nanoparticules à propriétés de surface contrôlées par polymérisation en miniémulsion pour la vectorisation de molécules actives / Synthesis of nanoparticules with controlled surface properties via miniemulsion polymerization for delivery of active molecules

Wu, Man 13 December 2007 (has links)
L'objectif de ce travail était la synthèse en une étape de nanoparticules à cœur de poly(n-butyl cyanoacrylate) et couronne hydrophile, par polymérisation en miniémulsion. Deux familles de polymères amphiphiles ont été utilisées pour stabiliser la polymérisation. La première est constituée de trois dérivés amphiphiles du dextrane synthétisés au laboratoire: DexP11, DexP16 et DexP22. La seconde est composée de dérivés commerciaux du POE: le Brij®78, le Brij®700, et le Tween®80. Après avoir vérifié leur stabilité dans les conditions de polymérisation, leurs propriétés tensioactives ont été caractérisées en tensiométrie dynamique. Bien que le n-butyl cyanoacrylate soit un monomère extrêmement réactif, des nanoparticules de poly(n-butyl cyanoacrylate) ont pu être synthétisées avec succès par polymérisation anionique et/ou radicalaire en miniémulsion. La nature et la concentration du polymère amphiphile dans la phase aqueuse lors de la polymérisation en miniémulsion contrôlent la taille des particules, leur taux de recouvrement et l'épaisseur de la couche hydrophile à leur surface. La masse molaire du polymère constituant le cœur de la nanoparticule est quant à elle influencée par le pH de la phase continue et le mode de polymérisation (anionique ou radicalaire). Enfin, l’étude de l'encapsulation et de la libération d'une molécule modèle, le pyrène, a été abordée / The aim of this study was the one-step synthesis via miniemulsion polymerization, of nanoparticles with a hydrophobic core based on poly(n-butyl cyanoacrylate) and a hydrophilic shell. Two families of amphiphilic polymers were used to stabilize the miniemulsion. The first one was constituted of three dextran derivatives synthesized in the laboratory: DexP11, DexP16 and DexP22. The other three stabilizers were commercial products based on PEO: Brij®78, Brij®700, and Tween®80. Their stability under the conditions used for miniemulsion polymerization was checked. Their adsorption at oil-water interface was studied by dynamic surface tension measurement. Despite the high reactivity of the monomer, nanoparticles of poly(n-butyl cyanoacrylate) were synthesized via anionic and/or radical miniemulsion polymerization. Particle size, surface coverage and hydrophilic layer thickness were controlled by the structure and the amount of the amphiphilic polymer in the continuous phase, while the molar mass of the poly(n-butyl cyanoacrylate) depending on the pH of the continuous phase and the polymerization mechanism (anionic or radical). Finally, the encapsulation and the release of a model compound were studied
6

Sistema nanoestruturado polimérico contendo hidroximetilnitrofural: preparação, caracterização físico-química e avaliação in vitro da atividade leishmanicida potencial / Nanostructured polymeric system containing hidroxymethylnitrofurazone: preparation, physicochemical characterization and in vitro evaluation of potential leishmanicidal activity.

Monteiro, Lis Marie 02 April 2013 (has links)
Na última década o emprego de nanotecnologia tem crescido exponencialmente em função das suas evidentes vantagens: maior eficácia terapêutica, menor toxicidade e liberação modificada do fármaco. Tais características permitem elevar os níveis do fármaco no compartimento intracelular, além de possibilitar sua liberação modificada no sítio específico. Essas vantagens vem ao encontro da otimização do tratamento da leishmaniose devido à falta de medicamentos seguros e de adequada atividade farmacológica. O objetivo do presente projeto constituiu-se na preparação e na avaliação das características físico-químicas da nanopartícula polimérica associada ao novo fármaco hidroximetilnitrofural (NFOH), desenvolvimento e validação do método analítico para a determinação da eficiência de encapsulação, avaliação a atividade leishmanicida in vitro em promastigotas, em macrófagos infectados por amastigotas de L. amazonensis e citotoxicidade do NFOH livre e nanoestruturado. As nanopartículas poliméricas de poli (butil cianoacrilato) (PBCA) obtidas apresentaram potencial zeta de -10,1 mV, tamanho médio de 151,5 nm, polidispersividade de 0,104 e distribuição unimodal muito próximos ao encontrado na literatura. O método analítico validado apresentou especificidade, linearidade, precisão, exatidão e robustez, mostrando-se adequado para a quantificação do NFOH em nanopartículas, o resultado final da eficiência de encapsulação foi de 64,5%. Os testes realizados em promastigotas e macrófagos infectados por amastigotas de L. amazonensis revelaram a maior atividade do fármaco nanoestruturado em relação ao fármaco livre e ao placebo. Os ensaios de citotoxicidade comprovaram que o fármaco, sistema nanoestruturado contendo NFOH e placebo apresentam baixa toxicidade. Logo, as nanopartículas obtidas contendo NFOH são uma alternativa promissora para o tratamento da leishmaniose. / In the last decade the use of nanotechnology has grown exponentially as a function of its obvious advantages: high therapeutic efficacy, lower toxicity and modified release of the drug. This feature allows raising the levels of the drug in the intracellular compartment, and enables the modified release of the drug in its specific site. These advantages come to meet the optimization of the treatment of leishmaniasis due to lack of drugs that are safe and appropriate pharmacological activity. The goal of this project consisted in the preparation and evaluation of physical and chemical characteristics of polymeric nanoparticle associated with new drug hidroxymethylnitrofurazone (NFOH), development and validation of analytical method for the determination of encapsulation efficiency, evaluating the leishmanicidal activity in vitro in promastigotes and in macrophages infected with amastigotes of L. amazonensis and finally cytotoxicity of free and nanostructured NFOH. The polymeric nanoparticles of poly(butyl cyanoacrylate) (PBCA) obtained showed zeta potential of -10.1 mV, average size of 151.1 nm, polydispersity of 0.104 and unimodal distribution very similar to that found in the literature. The validated method showed specificity, linearity, precision, accuracy and robustness, making it adequate for the quantification of NFOH nanoparticles, the final outcome of the encapsulation efficiency was 64.5%. Tests conducted on promastigotes and macrophages infected with amastigotes of L. amazonensis revealed the highest activity of nanostructured drug compared to free drug and placebo. The cytotoxicity assays showed that the NFOH, nanostructured system containing NFOH and placebo had low toxicity. Thus, the obtained nanoparticles containing NFOH are a promising alternative for the treatment of leishmaniasis.
7

Uso do cianoacrilato na retenção do reforço com resina composta em raiz fragilizada / Use of cyanoacrylate for retention of composite resin reinforcement in weakened roots

Gava, Ivan Lobo 29 May 2014 (has links)
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.
8

Influência do tipo e da técnica de aplicação de agente infiltrante na resistência mecânica de componentes produzidos por manufatura aditiva (3DP) / Influence of the type and the technique of application of infiltrating agent on the mechanical strength of components produced by additive manufacture (3DP)

Mello, Silvia Teixeira de [UNESP] 30 August 2017 (has links)
Submitted by Silvia Teixeira de Mello null (silviateixmello@gmail.com) on 2017-10-26T21:23:12Z No. of bitstreams: 1 DISSERTAÇÃO SILVIA MELLO 2017-3 CORRIGIDA 26-10.pdf: 3630355 bytes, checksum: 302fa9b705ffc11d7192a4b67392d0c6 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-10-31T18:59:52Z (GMT) No. of bitstreams: 1 mello_st_me_ilha.pdf: 3630355 bytes, checksum: 302fa9b705ffc11d7192a4b67392d0c6 (MD5) / Made available in DSpace on 2017-10-31T18:59:52Z (GMT). No. of bitstreams: 1 mello_st_me_ilha.pdf: 3630355 bytes, checksum: 302fa9b705ffc11d7192a4b67392d0c6 (MD5) Previous issue date: 2017-08-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Ao longo das duas últimas décadas, a contribuição da manufatura aditiva passou da confecção de um mero protótipo de um produto, no início de seu desenvolvimento, para a confecção de qualquer produto direto, presente em todos os setores industriais. Com este avanço, diferentes tecnologias da manufatura aditiva surgiram com o intuito de melhorar alguns parâmetros de produção. Neste meio, a tecnologia de impressão tridimensional 3DP, por consequência de suas várias características intrínsecas, se destaca para atender o setor biomédico, através da técnica de biomodelagem, que contribuem imensamente de forma didática e prática para a performance de cirurgias. Porém, há algumas limitações finais nas peças obtidas por esta tecnologia que devem ser contornadas, focando-se no tratamento adicional necessário destas peças, o pós-processamento, de modo a aprimorá-las, conferindo então sucesso ao destino destas. Neste trabalho, adotou-se a tecnologia de manufatura aditiva 3DP para estudar como a adição de diferentes agentes infiltrantes influenciam no acréscimo de densidade aparente e resistência mecânica de amostras feitas de componentes de gesso, constituídas por corpos de prova cilíndricos e prismáticos, de modo a simular a melhor composição para biomodelos. Para isto, o pós-processamento foi dividido em duas etapas. Na primeira etapa, foram aplicados separadamente nas amostras, quatro tipos de adesivos à base de etilcianocrilato, por gotejamento, e um à base de epóxi, por moldagem com pá. Já na segunda etapa, foram aplicados nas amostras, também separadamente, quatro tipos de adesivos à base de etilcianocrilato, por gotejamento e banho de imersão, e um à base de epóxi, por moldagem com pá. Além dos métodos de aplicação dos adesivos, as duas etapas se diferem também pelos binders utilizados para constituírem as amostras à base de gesso. Para ambas etapas, obteve-se o melhor resultado com o adesivo de cianocrilato de baixíssima viscosidade, capaz de provocar maiores variações de densidade aparente às amostras, além de maiores acréscimos de resistência. / Over the past two decades, the contribution of additive manufacturing has shifted from a mere prototype of a product at the beginning of its development to the production of any direct product present in all industrial sectors. With this advance, different technologies of the additive manufacturing appeared with the intention to improve some parameters of production. In this environment, three-dimensional printing 3DP technology, due to its various intrinsic characteristics, stands out to serve the biomedical sector through the biomodelling technique, which contribute immensely in a didactic and practical way for the performance of surgeries. However, there are some final limitations in the parts obtained by this technology that must be improved, focusing on the necessary additional treatment of these parts, the post-processing, in order to upgrade them, thus giving success to their destination. In this study, 3DP additive manufacturing technology was adopted to study how different infiltrating agents influence the increase in apparent density and mechanical strength of samples made of gypsum components, constituted by cylindrical and prismatic specimens, in order to simulate the best composition for biomodels. For this, the post-processing was divided in two stages. In the first stage, separately, four types of ethylcyanoacrylate-based adhesives were applied on the samples by dripping, and one epoxy-based adhesive was applied by shovel molding. In the second stage, also separately, four types of ethylcyanocrylate based adhesives were applied in the samples, by dripping and by dipping, and the epoxy-based, by shovel molding. Besides the adhesive application methods, the two stages also differ from the binders used to constitute the gypsum-based samples. For both stages, the best result was obtained by the cyanoacrylate adhesive with very low viscosity, capable of causing greater variations of apparent density and additions of strength to the samples.
9

Análise experimental de três métodos de aerostasia bronquial

ANGELIM, Jacqueline Loureiro 29 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-10-11T17:01:42Z No. of bitstreams: 1 Jacqueline Loureiro Angelim.pdf: 1021168 bytes, checksum: 196071628f9b10ff3bc708fe300d4091 (MD5) / Made available in DSpace on 2016-10-11T17:01:42Z (GMT). No. of bitstreams: 1 Jacqueline Loureiro Angelim.pdf: 1021168 bytes, checksum: 196071628f9b10ff3bc708fe300d4091 (MD5) Previous issue date: 2012-02-29 / The pulmonary lobectomy technique can be used on the lung cancer, lung lobe torsion, pulmonary laceration and lung abscesses treatment and among the postoperative problems the bronchial stump dehiscence, prolonged air leak and development of bronchopleural fistula are highlighted. These problems are usually resulting from malocclusion of the bronchial stump and most of the times the treatment for those problems consists on a new surgical procedure to reopen the chest cavity. The ain of the present paper was to evaluate the efficiency of n-butyl cyanoacrylate and nylon brassard as methods for occlusion of the bronchial stump and the aerostasia maintenance, comparing it with the manual suture technique on an experimental model using pig tracheobronchial trees, submitted to increasing levels of positive intrabrochial pressure. 30 pig tracheobronchial trees were used, where eight lobar bronchi from each piece were selected for studying, four of 10 mm and four of 5 mm. Thereafter, the trees and their bronchi were equally distributed into three experimental groups: Suture Group (SG) – manual suture with simple isolated stitches, using nº 2,0 surgical nylon; Cyanoacrylate Group (CG) - n-butyl Cyanoacrylate and Brassard Group (BG) – nylon brassards. After the bronchial stumps occlusion, the pieces were immersed in water and the “tire fitter test” was made placing the positive intrabrochial pressure at 30 cm of H2O for five minutes, and then gradually increased to a pressure at 100 cm of H2O. Leaks with a percentage of 1, 25% (1/80) were observed on groups SG and BG, when respectively submitted to a pressure at 30 cm of H2O and 100 cm of H2O. There were no leaks in any bronchial stumps on group CG. There were no statistically significant differences among the three treatments. It was concluded that, both n-butyl Cyanoacrylate such as nylon brassard, as also the manual suture, are effective methods for implementation and maintenance of bronchial aerostasia. / A técnica de lobectomia pulmonar pode ser utilizada para tratamento de neoplasias pulmonares, torção do lobo pulmonar, laceração pulmonar e abscessos pulmonares e dentre as complicações pós-operatórias, destacam-se a deiscência do coto brônquico, escape aéreo prolongado e desenvolvimento de fístula broncopleural. Esses problemas geralmente são decorrentes da má oclusão do coto brônquico e na maioria das vezes o tratamento consiste na realização de um novo procedimento cirúrgico com reabertura da cavidade torácica. Com o presente trabalho, objetivou-se avaliar a eficácia do n-butil cianoacrilato e da braçadeira de náilon como métodos para oclusão do coto brônquico e manutenção da aerostasia, comparando-o com a técnica de sutura manual, em modelo experimental empregando árvores traqueobrônquicas de suínos, submetidas a crescentes níveis de pressão positiva intrabrôquica. Foram utilizadas 30 árvores traqueobrônquicas, onde oito brônquios lobares de cada peça foram selecionados para estudo, sendo quatro de 10 mm e quatro de 5 mm. Posteriormente, as árvores e respectivos brônquios foram distribuídos equitativamente em três grupos experimentais: Grupo Sutura (GS) – sutura manual com pontos isolados simples, utilizando náilon cirúrgico n0 2.0; Grupo Cianocrilato (GC) - n-butil cianoacrilato e Grupo Braçadeira (GB) – braçadeiras de náilon. Após a oclusão dos cotos brônquicos, as peças foram imersas em água e realizado o teste de hermeticidade empregando-se pressão positiva intrabronquial de 30 cm de H20 por cinco minutos, sendo em seguida, gradualmente aumentada até atingir a pressão de 100 cm de H2O. Nos grupos GS e GB foram observados vazamentos com percentual de 1,25% (1∕80), quando submetidos a uma pressão de 30 cm de H20 e 100 cm de H20, respectivamente. No grupo GC não foi constatado vazamento em nenhum dos cotos brônquicos. Não foram evidenciadas diferenças estatísticas significativas entre três os tratamentos. Conclui-se que tanto o n-butil cianoacrilato, como a braçadeira de náilon, igualmente à sutura manual, são métodos eficazes na execução e manutenção da aerostasia bronquial.
10

Sistema nanoestruturado polimérico contendo hidroximetilnitrofural: preparação, caracterização físico-química e avaliação in vitro da atividade leishmanicida potencial / Nanostructured polymeric system containing hidroxymethylnitrofurazone: preparation, physicochemical characterization and in vitro evaluation of potential leishmanicidal activity.

Lis Marie Monteiro 02 April 2013 (has links)
Na última década o emprego de nanotecnologia tem crescido exponencialmente em função das suas evidentes vantagens: maior eficácia terapêutica, menor toxicidade e liberação modificada do fármaco. Tais características permitem elevar os níveis do fármaco no compartimento intracelular, além de possibilitar sua liberação modificada no sítio específico. Essas vantagens vem ao encontro da otimização do tratamento da leishmaniose devido à falta de medicamentos seguros e de adequada atividade farmacológica. O objetivo do presente projeto constituiu-se na preparação e na avaliação das características físico-químicas da nanopartícula polimérica associada ao novo fármaco hidroximetilnitrofural (NFOH), desenvolvimento e validação do método analítico para a determinação da eficiência de encapsulação, avaliação a atividade leishmanicida in vitro em promastigotas, em macrófagos infectados por amastigotas de L. amazonensis e citotoxicidade do NFOH livre e nanoestruturado. As nanopartículas poliméricas de poli (butil cianoacrilato) (PBCA) obtidas apresentaram potencial zeta de -10,1 mV, tamanho médio de 151,5 nm, polidispersividade de 0,104 e distribuição unimodal muito próximos ao encontrado na literatura. O método analítico validado apresentou especificidade, linearidade, precisão, exatidão e robustez, mostrando-se adequado para a quantificação do NFOH em nanopartículas, o resultado final da eficiência de encapsulação foi de 64,5%. Os testes realizados em promastigotas e macrófagos infectados por amastigotas de L. amazonensis revelaram a maior atividade do fármaco nanoestruturado em relação ao fármaco livre e ao placebo. Os ensaios de citotoxicidade comprovaram que o fármaco, sistema nanoestruturado contendo NFOH e placebo apresentam baixa toxicidade. Logo, as nanopartículas obtidas contendo NFOH são uma alternativa promissora para o tratamento da leishmaniose. / In the last decade the use of nanotechnology has grown exponentially as a function of its obvious advantages: high therapeutic efficacy, lower toxicity and modified release of the drug. This feature allows raising the levels of the drug in the intracellular compartment, and enables the modified release of the drug in its specific site. These advantages come to meet the optimization of the treatment of leishmaniasis due to lack of drugs that are safe and appropriate pharmacological activity. The goal of this project consisted in the preparation and evaluation of physical and chemical characteristics of polymeric nanoparticle associated with new drug hidroxymethylnitrofurazone (NFOH), development and validation of analytical method for the determination of encapsulation efficiency, evaluating the leishmanicidal activity in vitro in promastigotes and in macrophages infected with amastigotes of L. amazonensis and finally cytotoxicity of free and nanostructured NFOH. The polymeric nanoparticles of poly(butyl cyanoacrylate) (PBCA) obtained showed zeta potential of -10.1 mV, average size of 151.1 nm, polydispersity of 0.104 and unimodal distribution very similar to that found in the literature. The validated method showed specificity, linearity, precision, accuracy and robustness, making it adequate for the quantification of NFOH nanoparticles, the final outcome of the encapsulation efficiency was 64.5%. Tests conducted on promastigotes and macrophages infected with amastigotes of L. amazonensis revealed the highest activity of nanostructured drug compared to free drug and placebo. The cytotoxicity assays showed that the NFOH, nanostructured system containing NFOH and placebo had low toxicity. Thus, the obtained nanoparticles containing NFOH are a promising alternative for the treatment of leishmaniasis.

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