Resíduos lignocelulósicos são substratos proeminentes para a produção sustentável de polihidroxialcanoatos (PHAs) e etanol. A xilose é um dos principais componentes da lignocelulose, mas o aproveitamento eficiente desse açúcar ainda representa uma barreira técnica. O objetivo desse trabalho foi obter linhagens bacterianas mais eficientes no consumo desse açúcar. Foi introduzido maior número de cópias dos genes do catabolismo (xylAB) e transporte (xylFGH) de xilose, nas linhagens Escherichia coli KO11, produtora de etanol, e Burkholderia sacchari LFM 101, produtora de poli-3-hidroxibutirato (PHB). Os recombinantes foram avaliados quanto ao consumo de xilose e produção na presença e ausência de glicose. Para B. sacchari LFM 101 essa estratégia não incrementou o consumo desse açúcar. Para E. coli KO11 xylAB reduziu o tempo de consumo de xilose e aumentou a produção final de etanol em 30%, mas esse efeito foi prejudicado pela repressão catabólica; enquanto xylFGH foi deletério ao reduzir para quase zero o crescimento e produção de etanol por essa linhagem. / Lignocellulosic residues are remarkable substrates for the sustainable production of polyhydroxyalkanoates (PHAs) and ethanol. Xylose is one of the most important lignocelullose component but its efficient utilization still represents a technical barrier. The aim of this work was to obtain bacterial strains more efficient in the xylose consumption. Multiple copies of the catabolism (xylAB) and transport (xylFGH) genes of xylose were introduced in the ethanol producer Escherichia coli KO11 strain and the poly-3-hydroxybutyrate (PHB) producer Burkholderia sacchari LFM 101. The recombinants strains were evaluated for their production and xylose consumption in the presence and absence of glucose. This strategy did not increase xylose consumption in B. sacchari strains. The xylAB gene improved xylose consumption and increased the ethanol production about 30% in E. coli KO11, but this effect was impaired by catabolite repression; while xylFGH gene was deleterious to reduce the growth and ethanol production by this strain.

O tratamento de pacientes com doenças inflamatórias oculares crônicas frequentemente implica no uso prolongado de drogas anti-inflamatórias sistêmicas como, corticosteroides e outros imunossupressores, podendo acarretar efeitos colaterais importantes. O uso local destas drogas pode contribuir para aumentar seus efeitos desejáveis e reduzir os efeitos colaterais. Implantes intraoculares biodegradáveis são capazes de disponibilizar o fármaco diretamente na cavidade vítrea em doses terapêuticas por período prolongado. O copolímero do ácido lático e glicólico (PLGA) é um clássico exemplo entre os polímeros sintéticos biodegradáveis aplicados em sistemas de liberação de fármacos devido à sua biocompatibilidade e ausência de toxicidade em testes in vivo. A ciclosporina A (CsA) é um imunossupressor largamente usado na clínica médica, e também tem sido empregada no tratamento de várias doenças inflamatórias intraoculares. O objetivo deste estudo foi avaliar a farmacocinética vítrea da CsA, quando aplicada por meio de implante biodegradável de PLGA intravítreo na concentração de 350 µg em olhos de coelhos, assim como avaliar a ocorrência de toxicidade retiniana causada pela presença intraocular do sistema de liberação de fármacos por meio de eletrorretinografia (ERG) e histopatologia. Dos sessenta coelhos que foram utilizados neste estudo, 38 receberam o implante intravítreo de PLGA contendo CsA e 22 somente os veículos. Somente o olho direito dos coelhos foi analisado na pesquisa. O estudo teve duração de oito semanas. Quatro coelhos do grupo CsA e dois do grupo controle foram sacrificados semanalmente para a coleta do vítreo e posterior estudo farmacocinético. Quatro animais de cada grupo foram escolhidos para terem a pressão intraocular aferida semanalmente. Seis coelhos foram submetidos a ERG no início e ao final do estudo, sendo então sacrificados, e os olhos processados para estudos histológicos da retina. O período inferido de permanência da CsA na cavidade vítrea foi de 17 semanas. Nos dois grupos, com e sem CsA, não foram observadas alterações histológicas na retina, entretanto houve importante redução da onda b nas fases escotópicas da ERG no grupo CsA, indicando toxicidade na via dos bastonetes após as oito semanas de seguimento. Em resumo, estes resultados mostraram que a CsA aplicada por meio de implantes oculares de PLGA na dose de 350 µg não causa alterações histológicas da retina, mas provoca um padrão exclusivo de diminuição da onda b. Em estudos futuros, seria interessante avaliar os efeitos de implantes contendo concentrações inferiores a 350 µg de CsA, e também, veículos que permitam que sua liberação seja mais lenta, evitando-se, assim, a toxicidade observada nos ERGs e confirmar sua aplicabilidade clínica como alternativa interessante para o tratamento de doenças oculares inflamatórias crônicas. / Treatment of patients with chronic inflammatory ocular diseases often involves the use of systemic anti-inflammatory drugs such as corticosteroids and other immunosuppressive agents for a long period of time, which may cause significant systemic side effects. Intraocular use of these drugs may help to improve their local beneficial effects and reduce systemic adverse effects. Biodegradable intraocular implants are able to deliver drugs directly into the vitreous cavity in therapeutic doses for an extended period of time. Poly-lactic-co-glycolic acid (PLGA) is a good example of synthetic biodegradable polymers used in ocular drug delivery systems due to its biocompatibility and absence of toxicity. Cyclosporine A (CsA) is a largely used immunossupressor, and it has also been employed for treatment of various intraocular inflammatory diseases. The objective of this work was to evaluate the pharmacokinetics of CsA, when applied in biodegradable PLGA intravitreal implants in rabbit eye and its retina toxicity by electroretinography and histopathology. Right eyes of sixty rabbits were used on this study, 38 received the PLGA implant containing 350 µg of CsA, and 22 the implant without the drug and were followed during 8 weeks. Four animals of CsA group and 2 of control group were sacrificed weekly to have their vitreous samples collected for subsequent pharmacokinetic study. Four animals from each group were chosen to have intraocular pressure measured weekly. Six animals of each group underwent electroretinography tests at baseline and at the end of the study. Then they were sacrificed and had their eyes processed for histological studies of the retina. It was hypothetically calculated that CsA would take 17 weeks to be completely delivery by this system. Histologically the retina did not show alterations in both groups, but there was a significant reduction in the b wave of the scotopic ERG phases in the CsA group indicating toxicity of the rods pathway after 8 weeks of follow-up. In summary, PLGA implants with 350 µg of CsA does not cause retinal histological changes, but decreases b wave amplitude. In future studies it would be interesting to test lower concentrations of CsA using this delivery system to decrease possible toxicity and to guarantee its clinical applicability.

A review of the chemistry of poly(lactic acid) was carried out with a focus on techniques and applications of PLA polymer and copolymers with reference to some of the work that has been accomplished over the last 20 years or so. A review of the characterisation techniques used to analyse PLA polymers and copolymers was also carried out giving reference to the equipment and methods used herein. An investigation into the potential of PLA as the hydrophilic portion of a polymeric surfactant was carried out. To develop PLA based surfactants, the ring opening polymerisation of lactide was carried out in a melt in the presence of a long chain alcohol (C₇ to C₂₀) or diol (C₄ & C₆) to produce AB or ABA type polymers that follow the traditional surfactant template. Stannous octanoate and 4-dimethylaminopyridine were typically used as catalysts due to their high activity and relative cheapness. PLA only shows good hydrophilicity with up to 12 lactic acid units in the chain. Above this the electrostatic interactions between polymer chains reduced water solubility. It was also noted that D,L-lactide produced more water soluble polymers (syndiotactic) than the enantiomerically pure L-lactide (isotactic polymer chains). An investigation of the hydrophobic properties of PLA was carried out to evaluate their usefulness for other biodegradable surfactant applications. To this end an investigation of sugars as the hydrophilic portion of the molecule was carried out. Due to problems with solubilising sugars, they were deemed unsuitable for use as initiatiors within the scope of this research. Choline chloride was then investigated as a potential hydrophilic initiator and indeed has produced some of the most water soluble of PLA polymers. Choline chloride presented several challenges as an initiator, its high melting point resulted in polar solvents such as t-butanol being employed. Alternatively, more success was achieved by preparation of a choline chloride eutectic mixture prior to the polymerisation. It was discovered that a choline chloride/urea eutectic mixture was capable of self initiation, thus required no further addition of catalyst, this result shows a potential step forward in PLA green chemistry. A final investigation into producing surface-active PLA in a one-pot process that required only a hydroxycarboxylate initiator was carried out. The production of PLA sodium or potassium salts was carried out in a melt polymerisation and the results show some promise. Initiators that have been employed include a range of a, b and g-hydroxycarboxylic acids. These work through tautomerisation to the alkoxide, which then initiates a living type polymerisation of lactide to produce surface-active polymers. As well as the synthesis of these polymers some analysis of the physical and aqueous properties of these materials was carried out. PLA sodium salts were shown to have reasonable surfactant ability (~45 mNm⁻¹) and low CMC values of around 5x10⁻⁹ mol cm⁻³. They were also shown to have some properties as emulsifiers, and in some cases showed non-Newtonian fluid behaviour such as shear-thinning (thixotropy) and shear-thickening (dilatant). The thermal characteristics of the polymers such as T[subscript]g and stability were assessed as well as their ability to retain water.

La quantité de déchets augmente depuis plusieurs décénies, issus principalement de l'industrie du plastique. La production cumulée de matières plastiques au cours des dix dernières années est supérieure que pendant le dernier millénaire. Une des solutions pour réduire les impacts écologiques et économiques est de dévelopement de films et enrobages biodégradables et/ou comestibles.L'objectif de cette thèse est d'étudier des films et enrobages comestibles à base d'amidon. Quinze types de solutions filmogènes ont été formulés: 3 types d’amidons, amidon + protéines, amidon + huile de colza, amidon + plastifiant. Afin de mieux comprendre le rôle des constituants et les interactions mises en jeu, les propriétés physico-chimiques et structurales des films ont été réalisées. Enfin, les films présentant les meilleurs compromis ont été appliqués sur des prunes.L’étude physico-chimique des films à base d’amidon de maïs, de pommes de terre et de de blé ont permis de retenir l’amidon de blé pour les études suivantes. Une quantité de plastifiant de 50% (par rapport à la masse sèche de biopolymère) a été sélectionnée car elle permet d'obtenir des films souples et resistants sans blanchiment. Afin d'améliorer l'efficacité barrière à l'humidité, de l'huile de colza a été ajoutée par laminage sur le film d’amidon. Les observations de la microstructure montrent une dispersion de gouttelettes d’huile dans la matrice à la place d’une structure multicouche amidon-huile-amidon. Diverses proportions amidon/protéine ont été testées pour améliorer les propriétés fonctionnelles des films. Plus la teneur en protéines est élevée, meilleure est l'efficacité barrière à la vapeur d'eau, à l'oxygène ou aux arômes. En effet, les films sont plus denses et homogènes en présence des protéines. A partir de la meilleure compréhension du rôle de la composition et de la structure sur les performances des films, plusieurs formulations ont été testées comme enrobage ou film sur des prunes fraîches. L’analyse thermographique a été utilisée pour étudier le comportement des prunes pendant le stockage, l’enrobage/film composé de l’amidon enrobage s’est avéré efficace pour retarder la dégradation des fruits. / The amount of waste increased annually, mainly from plastic industry. Plastic materials were more produced during the only last ten years than during the last millennium. A potential solution of the ecological and economic problems can be biodegradable or edible films and coatings. The goal of this thesis was to study edible films and coatings based on starch. Fifteen types of film-forming solutions were made: 3 types of starch, starch + different amounts of plasticizer, starch + proteins, starch + oil. To better understanding the interaction between film components, physical, chemical and functional tests were done. Finnaly, validation on real foods (plums) as coatings and films helped to improved edible barrier films for fruit and vegetable preservation.Preliminary physico-chemical studies of corn, potato and wheat starch film properties allowed choosing the wheat starch-based films further experiments. Then, a 50% amount of plasticizer related to dry biopolymer weight was selected aiming to obtain films being not too rigid, that did not break and without blooming. To prove the barrier moisture efficacy, rapeseed oil was added as multilayers films. Microstructure observations displayed that oil was dispersed as droplets instead of layer, thus emulsion-based films were obtained instead of multilayer starch-oil-starch films. Various ratios of starch/protein were assessed to improve functional properties of films. The more the protein content was, the better the barrier efficiency against water vapour, oxygen or aroma were. Indeed, higher protein content films were more dense and homogeneous. From these data obtained on films, and the better understanding how composition and structure affect film performances, several recipes were tested as coatings or films for wrapping fresh plums. Thermographic analysis was used to study the plums behavior during storage, and starch coating was efficient to delay fruit degradation. / Z każdym rokiem wzrasta liczba produkowanych odpadów, w szczególmości tych z plastiku. W ciągu pierwszych dziesięciu lat wyprodukowano więcej tworzyw sztucznych niż w przeciągu całego ubiegłego tysiąclecia. Rozwiązaniem tych ekologicznych i ekonomicznych problemów mogą okazać się filmy i powłoki do żywności. Celem tej pracy były studia nad jadalnymi filmami i powłokami na bazie skrobi. Piętnaście rodzajów roztworów powłokotwórczych zostało wytworzonych: z 3 typów skrobi, skrobia + różne stężenia plastyfikatora, skrobia + białka, skrobia + olej. W celu lepszego zrozumienia interakcji pomiędzy komponentami filmu właściwości fizyczne, chemiczne i funkcjonalne zostały zmierzone. W ostatnim etapie walidacja na prawdziwej żywności (powlekanie i pakowanie śliwek) pomogła w udowodnieniu istnienia właściwości barierowych owoców i warzyw podczas przechowywania.Próbne testy fizyko-chemiczne skrobi kukurydzianej, ziemniaczanej i pszenicznej pomogły w wyborze skrobi otrzymywanej z pszenicy do dalszych badań. Następnie wybrano zawartość plastyfikatora. 50% glicerolu względem suchej masy substancji powłokotwórczej nie powodowało twardości i pękania filmów ani też tzw. efektu kwitnienia (intensywnie żółty/ pomarańczowy kolor filmów). W celu poprawy właściwości barierowych olej rzepakowy został dodany. Zdjęcia mikroskopowe obrazują zawieszone krople oleju w matrycy jako emulsja zamiast dodatkowej warstwy, której oczekiwano. Do skrobi zostały dodane również białka serwatkowe w kilku proporcjach. Im więcej białek jest w stosunku procentowym skrobia/proteiny tyym lepsze są właściwości barierowe dla pary wodnej, tlenu i aromatów. Dodatkowo filmy zawierające więcej protein w stosunku procentowym są bardziej gęste i jednolite. Uzyskane informacje pozwoliły na lepsze zrozumienie wpływu kompozycji i struktury filmów i powłok na pakowanie świeżych śliwek. Analiza z użyciem kamery termowizyjnej pozwoliła na ocenę zmian w owocach podczas przechowywania, zaś powłoka skrobiowa efektywnie opóźniała procesy degradacyjne w owocach.

Nanoparticles from biodegradable polymers are considered one of the most promising systems for biomedical application as drug delivery systems. Therefore, the synthesis and characterization of a new aliphatic biodegradable copolyester named PBS/PBDL (poly(butylene succinate-co- butylene dilinoleate)) intended to the application as drug delivery system is reported in the thesis. Surfactant-free biodegradable and narrowly distributed, nanosized spherical particles (RH < 60 nm) have been produced from the biodegradable material by applying a single-step nanoprecipitation protocol. The size of the generated polymer nanoparticles (PNPs) could be controlled by adjusting the polymer concentration, the choice of organic solvent, mixing different organic solvents or by changing temperature and ionic strength. By optimizing such parameters sub-100 nm uniform PNPs can be produced through this methodology including the advantage and ability to scale-up production. The nanoparticles structure was characterized in detail by employing a variety of scattering techniques and transmission electron microscopy (TEM). Combined static light scattering (SLS) and dynamic light scattering (DLS) measurements suggested that the nanoparticles comprise a porous core conferring them a non-compact characteristic. Their porosity...

This diploma paper deals with contemporary practice in dispose of biodegradable waste, especially biodegradable communal waste (biowaste) in the Czech Republic. It explains fundamental terms, points out relevant legal rules and describes methods of biowaste handling. It evaluates collection and utilization systems in two cities in the way of comparison method. It compares them from cost and benefits (economic, environmental) points of view. The main purpose of the diploma paper is general introduction into the issue, pointing out negative effect of biowaste landfilling and presentation of actual systems of utilization. Also the work points out contemporary trend consisting in raising separation and reducing biodegradable communal waste landfilling.

La stabilisation dite de Pickering repose sur l'utilisation de particules solides au lieu des émulsifiants. Leur forte adsorption aux interfaces confère à celles-ci une rigidité les protégeant de la coalescence. Ce travail se partage en quatre grandes parties. Un premier volet traite de la fabrication de ces particules et de leur caractérisation physico-chimique. Une deuxième partie traite de la formulation d'émulsions H/E selon deux procédés différents et leur caractérisation. La troisième partie avait pour but l'investigation du comportement de ces particules à l'interface H/E par diffusion de neutrons. La dernière partie traite de l'évaluation de ces émulsions pour l'application cutanée. Ce travail a pour objectif de formuler des émulsions de Pickering en utilisant des particules polymériques biodégradables. Des particules individualisées formées à partir de copolymères di-blocs du type : PCL-b-PEG et PLA-b-PEG, ont été fabriquées selon un procédé de nanoprécipitation innovant. Elles ont été caractérisées en termes de taille et de stabilité. Leur structure interne a également été investiguée par RMN et cryo-MET. Leur aptitude à stabiliser des émulsions H/E très concentrées a été démontrée. L'impact du procédé d'emulsification sur les propriétés finales a été souligné et l'adsorption de particules en forme de chapelets serrés à l'interface a été visualisée par diffusion de neutrons et microscopie électronique après cryofracture. L'absorption du rétinol dans la peau à partir de ces émulsions innovantes, a montré une accumulation accrue de cet actif dans le stratum corneum comparée à celle d'une émulsion stabilisée par des tensioactifs classiques. Cette absorption cutanée a été montrée dépendre du procédé de fabrication des émulsions. Les particules en suspension aqueuse ont aussi été testées pour l'encapsulation et la libération cutanée du rétinol. Les résultats ont montré l'influence de la constitution interne des particules (PCL ou PLA) sur l'absorption du rétinol dans la peau. L'utilisation de polymères biodégradables apporte de nouvelles perspectives dans la formulation des émulsions de Pickering à usage cosmétique ou pharmaceutique, en s'affranchissant des effets jugées hasardeux pour la santé humaine des particules inorganiques / The so-called Pickering stabilization is based on the use of solid particles instead of emulsifiers. Their strong adsorption at interfaces confers rigidity preventing them from coalescence. This work is divided into four main parts. The first part deals with the manufacture of these particles and their physicochemical characterization. A second part deals with the O/W emulsions formulation according to two different methods and their characterization. The third part is an investigation into the behavior of these particles at the O/W interface by small angle neutron scattering. The last part deals with the evaluation of these emulsions for their application to skin delivery. This work aims at the preparation of Pickering emulsions using biodegradable polymeric particles. Individual particles formed from diblock copolymers such as: PCL-b-PEG and PLA-b-PEG, were made by an innovative nanoprecipitation process. They were characterized in terms of their size and stability. Their internal structure was also investigated by NMR and cryo-TEM. Their ability to stabilize highly concentrated O/W emulsions has been demonstrated. The impact of the emulsification process on the final properties was emphasized and the adsorption of particles as tight necklaces at the interface was visualized by neutron scattering and freeze-fracture electron microscopy. The skin absorption of retinol from these innovative emulsions showed enhanced accumulation of the asset in the stratum corneum compared to conventional surfactant-stabilized emulsions. Such skin absorption of retinol was shown to depend on the manufacturing method of the emulsions. Particles in aqueous suspension were also tested for encapsulation and delivery of retinol in skin. The results showed the influence of the internal structure of the particles (PCL or PLA) on the absorption of retinol in the skin. The use of biodegradable polymers brings new perspectives in the formulation of Pickering emulsions for cosmetic or pharmaceutical use, while avoiding the effects of inorganic particles considered hazardous to human health

This thesis covers the design of an automated multiunit composting system (AMUCS) that was constructed to meet the experimental apparatus requirements of the ASTM D5338 standard. The design of the AMUCS is discussed in full detail and validated with two experiments. The first experiment was used to validate the operation of the AMUCS with a 15 day experiment. During this experiment visual observations were made to visually observe degradation. Thermal properties and stability tests were performed to quantify the effects of degradation on the polymer samples, and the carbon metabolized from the degradation of samples was measured. The second experiment used the AMUCS to determine the effect of synthetic clay nanofiller on the aerobic biodegradability behavior of poly (3-hydroxybutyrate-co-3-hydroxyvalerate).

Orientador: Antonio Wilson Sallum / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T23:52:25Z (GMT). No. of bitstreams: 1 Moura_LucasAlves_D.pdf: 4231687 bytes, checksum: ec30a84348074c7f0f52d37535f57bbe (MD5) Previous issue date: 2015 / Resumo: O objetivo deste estudo foi avaliar o efeito da associação da administração local de nanoesferas contendo doxiciclina (DOX) com o debridamento periodontal no tratamento da periodontite crônica avançada. As nanoesferas foram preparadas pelo método da dupla emulsão (W/O/W), e caracterizadas quanto à morfologia através da microscopia eletrônica de varredura (MEV), e quanto à interação polímero (PLGA) e DOX através da espectroscopia infravermelha da transformada de Fourier (FTIR). A avaliação da liberação controlada de DOX foi feita através da cromatografia líquida de alta eficiência (HPLC), a partir do fluido gengival sulcular (GCF) coletado nos períodos: 2, 5, 7, 10, 15 e 20 dias após aplicação das nanoesferas. Foi realizado um ensaio clínico randomizado controlado duplo cego, incluindo 30 pacientes diagnosticados com periodontite crônica que apresentavam sete sítios com sangramento à sondagem e profundidade de sondagem (PS) ? 5 mm, sendo 2 dentes com PS ? 7 mm. Os pacientes foram aleatoriamente divididos em 2 grupos e receberam os seguintes tratamentos: debridamento periodontal por 45 minutos associado à administração local de nanoesferas contendo doxiciclina nos sítios com PS ? 5 mm (DB+DOX) ou debridamento periodontal por 45 minutos associado à aplicação de nanoesferas vazias (DB). Foram avaliados os seguintes parâmetros clínicos: Índice de Placa (IP), Sangramento à Sondagem (SS), Profundidade de Sondagem (PS) e Nível de Inserção Clínica (NIC), no baseline, 3 e 6 meses após a terapia. A avaliação microbiológica foi feita por meio da reação de cadeia de polimerase ¿ tempo real ("real time" - PCR) para detecção das bactérias: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans e Prevotella intermedia, provenientes do biofilme subgengival coletado no baseline, 1, 3 e 6 meses após o tratamento. Os resultados foram comparados por meio do teste de análise de variância com medidas repetidas, com nível de significância de 5%. Foram obtidas nanoesferas variando de 700 nm a 4 um. Através do FTIR observou-se boa interação da DOX com o PLGA, sem alterações das propriedades químicas de nenhum dos compostos. Após a aplicação das nanoesferas observou-se uma liberação de DOX constante no GCF até o vigésimo dia pós-tratamento, acima da concentração inibitória mínima. No grupo DB+DOX houve redução significativa da PS e ganho de inserção clínica nas bolsas profundas e moderadas em relação ao baseline e entre grupos. Observou-se redução significativa dos níveis bacterianos pós-tratamento, sendo o grupo DB+DOX mais eficaz em manter os níveis mais baixos após 6 meses do tratamento. Dentro das limitações deste trabalho, os resultados sugerem que as nanoesferas de PLGA são efetivas como sistema de liberação controlada local de DOX e quando associadas ao debridamento periodontal podem promover resultados superiores em relação à terapia mecânica isoladamente / Abstract: The aim of this study was to assess the effect of the association of local administration of nanospheres loading doxycycline (DOX) with the periodontal debridement treating advanced chronic periodontitis. Nanospheres were made by double-emulsion method (W/O/W) and characterized regarding morphology, by scaning eléctron microscopy (SEM); and drug/polymer interaction, by Fourier transform infrared spectroscopy (FTIR). The DOX controlled release was assessed by high performance liquid chromatography (HPLC) of gingival crevicular fluid (GCF) samples collected 2, 5, 7, 10, 15 and 20 days after treatment. It was performed randomized double-blinded clinical trial, with thirty patients diagnosed with chronic periodontitis presenting at least seven sites with bleeding on probing and probing depth (PD) ? 5 mm, and 2 sites with PD ? 7 mm. The patients were randomly allocated in two groups receiving interventions as followed: 45 minutes periodontal debridement + subgengival nanospheres loading DOX (DB+DOX); and 45 minutes periodontal debridement + subgengival void nanospheres (DB). Plaque index (IP), bleeding on probing (BP), probing depth (PD) and clinical attachment level (CAL) were evaluated on baseline, 3, and 6 months after therapy. Real-time polymerase chain reaction (real-time PCR) was used to quantify Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans and Prevotella intermedia from subgingival biofilm samples collected on baseline, 1, 3 and 6 months after treatment. The results were compared by variance analyses test for repeated measures, with significance of 5%. Nanospheres varying from 700 nm to 4 um were obtained. There was a good interaction between DOX and PLGA, with no chemical properties alterations. After local administration of the nanospheres, it was observed constant DOX release in the GCF until 20th day post-treatment, with concentration above the minimum inhibitory concentration. DB+DOX group showed significant PD reduction and CAL gain in deep and moderates pockets comparing to baseline and between groups. It was observed significant reduction of bacteria levels along follow up period, and DB+DOX group was more eficiente in keeping lower levels of bacteria after 6 months from treatment. Within limitations of this study, the results can suggest that PLGA nanospheres are effective carriers for controlled release of DOX and when used adjunctively to periodontal debridement, improved results can be achieved compared to mechanical therapy alone / Doutorado / Periodontia / Doutor em Clínica Odontológica

O processo de extração do óleo de mamona gera, como subproduto, uma torta rica em proteínas, que tem sido utilizada como adubo e contra fitonematóide, devido à sua toxicidade. Entretanto, as proteínas da torta de mamona são ricas em aminoácidos que permitem modificação química com aldeídos bifuncionais, como o glutaraldeído e o glioxal, o que pode ser interessante para a produção de filmes biodegradáveis com propriedades físicas adequadas ao emprego na agricultura. Assim, o objetivo geral deste trabalho foi a produção e caracterização de filmes à base de proteínas extraídas da torta de mamona e reticuladas com glioxal ou glutaraldeído e plastificados com glicerol. Especificamente, estudaram-se o efeito da concentração de proteína e do tipo de reticulante, e o efeito da concentração do reticulante sobre algumas propriedades dos filmes. Os filmes foram produzidos com uma técnica conhecida como tipo \"casting\", que consiste na desidratação de uma solução filmogênica (SF). Os filmes foram submetidos a testes para determinação da umidade, espessura, propriedades mecânicas (testes de tração e perfuração), permeabilidade ao vapor de água, solubilidade em água, cor, opacidade, brilho, além da microestrutura, por microscopia eletrônica de varredura. A concentração da proteína e o tipo de reticulante não influenciaram a umidade, espessura, microestrutura e propriedades óticas. Mas, de maneira geral, os filmes produzidos com o glioxal apresentaram melhores propriedades mecânicas e menor solubilidade em água que aqueles produzidos com glutaraldeído, sendo que a concentração de 6g de proteínas/100g de SF foi a formulação que apresentou os melhores resultados para os testes de tração e de solubilidade em água. Este resultado é muito importante para o emprego dos filmes na agricultura. Por outro lado, a concentração do glioxal não teve efeito sobre a umidade, espessura, propriedades óticas, microestrutura e nem sobre a permeabilidade ao vapor de água, influenciando apenas a solubilidade e as propriedades mecânicas. O teor de glioxal que proporcionou melhores propriedades mecânicas e baixa solubilidade em água foi de 5g/100g de proteínas. Filmes produzidos nessas melhores condições foram submetidos a análises complementares envolvendo testes de hidrofobicidade, propriedades térmicas, espectroscopia de infravermelho com transformada de Fourier, isoterma de sorção e biodegradabilidade. Finalmente, pode-se concluir que as proteínas da torta de mamona são capazes de formar uma matriz bem estruturada e que suas propriedades podem ser melhoradas com a adição de glioxal. / The extraction process of castor oil produces, as a co-product, a cake rich in proteins which has been used as a fertilizer and against plant parasitic nematode, because of its toxicity. However, the proteins of castor bean cake are rich in amino acids which allow chemical modification with bifunctional aldehydes such as glutaraldehyde and glioxal. This may be interesting for the production of biodegradable films with adequate physical properties to the use in agriculture. The objective of this work was the production and characterization of films based on proteins extracted from the castor bean cake and crosslinked with glyoxal or glutaraldehyde and plasticized with glycerol. Specifically, we studied the effect of protein concentration and type of crosslinker and the effect of the crosslinker concentration on some properties of the films. The films were produced with a technique known as \"casting\", which consists of drying a film solution (FS). The films were tested for determination of moisture content, thickness, mechanical properties (tensile and puncture tests), water vapor permeability, water solubility, color, opacity, gloss, and the microstructure by scanning electron microscopy. The protein concentration and type of crosslinking did not affect the moisture content, thickness, microstructure and optical properties. But, in general, films made with glyoxal showed improved mechanical properties and lower water solubility than those produced using glutaraldehyde. And, the concentration of 6g proteins/100 g of FS was the formulation that presented the best results for the tensile tests and water solubility. This result is very important for the use of films in agriculture. Moreover, the concentration of glyoxal had no effect on the moisture content, thickness, optical properties, or on the microstructure and permeability to water vapor, influencing only the solubility and mechanical properties. The concentration of glyoxal that provided the best mechanical properties and low water solubility of proteins was 5g/100g of gelatin. Films produced in the best conditions were subjected to further analyzes involving tests of hydrophobicity, thermal properties, spectroscopy, Fourier transform infrared spectroscopy, water vapor sorption isotherm and biodegradability. Finally, it can be concluded that the protein of castor bean cake are capable of forming a matrix structured and that their properties can be improved with the addition of glyoxal.