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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.
201

Relevância dos proteoglicanos como biomarcadores prognósticos e preditivos em carcinomas não-pequenas células e seu impacto na carcinogênese pulmonar / Clinical relevance of matrix proteoglycans as predictors of lung cancer patients outcome

Rangel, Maristela Peres 12 December 2016 (has links)
Introdução. Os glicosaminoglicanos e os proteoglicanos são moléculas abundantes na matriz extracelular. Vários estudos têm demonstrado que uma produção ou degradação aberrante dessas moléculas tem influência no comportamento do câncer de mama, cólon e pâncreas. Outras proteínas como o solCD44 e a cofilina-1 também tem demonstrado influência direta na progressão dos tumores. Desta forma, a análise da expressão destas moléculas em tecidos e fluidos corporais tem despertado grande interesse como rastreador de indivíduos de alto risco e marcador diagnóstico e/ou prognóstico da doença. Objetivos. Conhecer o impacto do ácido hialurônico e dos proteoglicanos (biglicam, glipicam, perlecam, sindecam e versicam) na carcinogênese bem como seu impacto na sobrevida dos pacientes; verificar se a concentração de solCD44 e cofilina-1 presente no escarro de pacientes com câncer de pulmão permite rastreá-los entre pacientes com doença pulmonar obstrutiva crônica e voluntários saudáveis. Resultados. Uma associação significativa direta foi encontrada entre os tumores com alto percentual de expressão de AH e de microvasos no estroma tumoral. As concentrações de heparam e condroitim sulfato nas amostras tumorais foram mais elevadas quando comparadas às amostras não tumorais. Com exceção do sindecam, todos os outros proteoglicanos apresentaram uma expressão gênica significativamente menor nos tecidos tumorais e biglicam e versicam apresentaram associações com as características clinico patológicas. A expressão proteica de biglicam, perlecam e versicam foi significativamente maior no tecido normal do que nas áreas de estroma tumoral e de células tumorais. Pela análise de regressão de COX controlada para idade, tipo histológico e expressão gênica de biglicam, sindecam e glipicam obtiveram alta taxa de sobrevida os pacientes do sexo feminino com elevada expressão gênica de perlecam e menor risco de óbito em estadio T1, ausência de metástases nodais e expressão gênica de versicam. A Maristela Peres Rangel Tese de doutorado - USP concentração de cofilina demonstrou-se mais elevada no escarro de pacientes com câncer de pulmão quando comparado ao escarro de pacientes de alto risco e de voluntários saudáveis. A concentração de solCD44 também demonstrou-se mais elevada no escarro de pacientes com câncer de pulmão quando comparado ao escarro de pacientes de alto risco e de voluntários saudáveis. Através da curva ROC, a cofilina-1 presente no escarro foi capaz de distinguir os pacientes de alto risco dos pacientes com câncer de pulmão com área abaixo da curva de 0.69 e com um ponto de corte de 802.5 pg/mL a curva apresentou 60% de sensibilidade e 54% de especificidade. O solCD44 presente no escarro também foi capaz de distinguir os pacientes de alto risco dos pacientes com câncer de pulmão através da curva ROC com área abaixo da curva de 0.67 e com um ponto de corte de 65.8 pg/mL a curva apresentou 50% de sensibilidade e 84% de especificidade. Conclusão. A expressão do ácido hialurônico demonstrou ter correlação no processo de crescimento tumoral através da angiogênese. A análise biomolecular apontou a diminuição dos proteoglicanos no tecido tumoral e, portanto, estes podem ser potenciais biomarcadores prognósticos de câncer de pulmão. As análises feitas em escarro demonstraram que a elevada expressão proteica de solCD44 e da cofilina-1 no escarro nos pacientes com câncer de pulmão mostram-se como promissores alvos de detecção do CP / Introduction. The relationship between the extracellular matrix (ECM) components and cancer cells have an important role on cancer development and progression. Between the most important molecules present on the ECM are the glycosaminoglycans and their respective proteoglycans. Studies have reported that they have different behaviours when in the presence of malignant tissues and influence the development of breast, pancreas and colon cancers. Likewise, proteins as solCD44 and cofilin-1 also have shown direct influence in tumor progression. Regarding that, there is growing interest among scientists in analyzing the expression of these molecules in body fluids as a screening tool of high risk patients and as a diagnostic and prognostic lung cancer biomarker. Objectives. The aims of this study were to recognize the impact of hyaluronan and the proteoglycans (biglycan, glypican, perlecan, syndecan e versican) on lung cancer carcinogenesis as well as its impact on patient\'s survival; verify if the solCD44 e cofilina-1 concentrations in the sputum of lung cancer patients could distinguish them from patients with COPD and healthy volunteers. Results. A direct association was found between tumors expressing high amounts of hyaluronan and CD34 in tumoral stroma. Heparan and chondroitin sulphate concentrations were higher in tumor specimens when compared to normal lung tissue. All proteoglycans, in exception of syndecan, showed a lower expression in tumoral tissue and biglycan and versican showed association with the clinical pathological features. Protein expression of biglycan, perlecan and versican was higher in the normal tissue when compared to stroma and tumoral cells. COX regression controlled by age, histological types and gene expression of biglycan, syndecan e glypican demonstrated that female patients had higher survival rates with high gene expression of perlecan and the patients with T1 stage, lack of linfonode Maristela Peres Rangel Tese de doutorado - USP metastasis and gene expression of versican had lower risk of death. Cofilin-1 concentration was higher in the sputum of lung cancer patients when compared to a high risk group and healthy volunteers. Also, the solCD44 concentration was higher in the sputum of lung cancer patients when compared to a high risk group and healthy volunteers. ROC cruve analysis demonstrated that sputum cofilin-1 was capable to distinguish high risk patients from lung cancer patients with na area under the curve of 0.69 and with a cut off at 802.5 pg/mL the curve presented 60% de sensitivity and 54% specificity. Sputum solCD44 was also capable to distinguish high risk patients from lung cancer patients with na area under the curve of 0.67 and with a cut off at 65.8 pg/mL the curve presented 50% de sensitivity and 84% specificity. Conclusions. Hyaluronan expression showed a correlation with tumoral growth through angiogenesis processes. The biomolecular analysis demonstrated that matrix proteoglycans are potencial lung cancer prognostic biomarkers. Sputum analyses showed that solCD44 and cofilin-1 are potencial molecules in lung cancer detection
202

Développement de microparticules bioadhésives pour l'administration vaginale de probiotiques / Development of bioadhesive microparticles for vaginal use of probiotics

Pliszczak, Dorothée 23 November 2011 (has links)
Lors d’infections vaginales, divers pathogènes se développent au détriment de la flore locale. L’utilisation de lactobacilles en traitement prophylactique et/ou curatif pourrait pallier ce problème. Le but de ce travail de thèse a été de développer des microparticules mucoadhésives à base de pectine et d’acide hyaluronique (HA) pour la libération intravaginale de probiotiques. Quatre souches probiotiques ont été associées à des prébiotiques afin d’obtenir un effet symbiotique. Les microparticules ont été formulées par émulsification-gélification ionique. Dans un premier temps, l’étude de l’influence de différents paramètres de procédé et de formulation a permis de définir les conditions opératoires pour l’obtention de microparticules d'environ 140 µm de diamètre encapsulant des probiotiques viables. Puis, les propriétés mucoadhésives des microparticules ont été évaluées in-vitro et ex-vivo par des mesures rhéologiques en mode dynamique et par des tests d’indentation. La présence d’HA entraine une augmentation importante du pouvoir bioadhésif des particules. Enfin, ces microparticules ont été incorporées dans des comprimés par un procédé de granulation humide. L’encapsulation des bactéries permet leur protection lors du procédé de compression. De plus, contrairement aux formes classiques d'administration des probiotiques, les microparticules permettent d'obtenir un profil de libération prolongée des bactéries sur environ 10h contre 1h dans le cas d’un comprimé comportant des probiotiques non encapsulés. Un début de prolifération bactérienne s’opère entre 16 et 24 heures. Le comprimé ainsi développé est tout-à-fait adapté à une application vaginale / More than 300 millions of women around the world have urinary or vaginal infections, including yeast vaginitis and bacterial vaginosis. Vaginal use of probiotics offers a potential alternative approach to health restoration and maintenance of the vaginal microflora. Moreover, prebiotics may be combined with probiotics to obtain a symbiotic effect. The aim of this work was to develop pro- and pre-biotics-loaded bioadhesive microparticles by using pectin and hyaluronic acid (HA). Four probiotic strains classically used in vaginal applications and one prebiotic have been selected. Microparticles were produced by emulsification/gelation method using calcium as cross-linking agent. The study of process and formulation parameters allowed obtaining microparticles with a mean diameter of 140 µm which encapsulated between 1010 to 1011 cfu/g of microparticles. Their mucoadhesive properties have been proved both by rheological and indentation measurements in in-vitro and ex-vivo conditions. Moreover, results have shown that HA addition in pectin solutions enhanced the bioadhesive properties of the gel-based microparticles. Afterwards, microparticles have been incorporated inside tablet by wet granulation. Microencapsulation of probiotics allowed protecting them during the compression process. The kinetic release of probiotics studies in in-vitro conditions exhibited a sustained release profile for 10 hours against 1h for unencapsulated probiotics. A beginning of probiotic strain proliferation was observed between 16 to 24 hours. The developed tablet is well-suited to vaginal application
203

Polymères à activités biologiques : nanoparticules et multivalence / Polymers with biological activities : multivalent and nanoparticle effect

Duan, Haohao 16 September 2016 (has links)
Les nanoparticules à base d’acide hyaluronique (AH) sont utilisées pour de nombreuses applications pharmaceutiques. Elles peuvent cibler les tumeurs par interaction avec le CD44,qui est un récepteur biologique surexprimé à la surface de certaines cellules cancéreuses. Dans ce projet nous explorons l’application potentielle de ces nanoparticules dans les domaines cosmétiques, car l’AH est aussi un ingrédient important pour l’hydratation et le renouvellement de la peau. Les copolymères à bloc à base de polypeptides et de polysaccharides ont été synthétisés par une combinaison de polymérisation par ouverture de cycle et de couplage par chimie « click ». Les nanoparticules ont été obtenues par l’auto assemblage de ces copolymères en utilisant un procédé de nano precipitation, dont la taille et la morphologie sont contrôlées par les paramètres expérimentaux. L’interaction entre les nanoparticules d’AH et le CD44 a été quantifiée par la résonance de plasmon de surface(RPS). En comparant avec l’AH libre en solution, les nanoparticules d’AH ont montré une interaction plus efficace avec le CD44, mettant ainsi en évidence un effet de multivalence des nanoparticules. Finalement, la dégradation enzymatique de ces nanoparticules d’AH a été évaluée avec deux types de hyaluronidases, HYAL1 et SPAM-1. La digestion des nanoparticules de l’AH a été significativement ralentie par rapport à l’AH libre. De manière très surprenante, ces nanoparticules de AH ont pu inhiber l’activité de l’enzyme HYAL1 et protéger l’AH libre dans la solution. Enfin, des ligands du récepteur TLR2 de type lipopeptide ont été synthétisés et leurs performances via TLR2 ont été évaluées par RPS. / Nanoparticles based on hyaluronic acid (HA) are widely used in pharmaceutics. They can target the tumor by the interaction with CD44, a biological receptor overexpressed in some cancer cells. In this project, we investigate the potential applications of these nanoparticles in cosmetics, since HA is also an important ingredient for the skin hydration and renewing. Block copolymers based on polypeptides and polysaccharides were synthesized using a combination of ring opening polymerization and “click chemistry”. The nanoparticles were formed by the self-assembly of these block copolymers using a nanoprecipitation process, and their size and morphology were controlled by the experimental conditions. The interaction between nanoparticles and CD44 were measured by surface plasmon resonance(SPR). Compared to free hyaluronic acid chains in solution, the HA-based nanoparticles could interact more efficiently with CD44, thus demonstrating a multivalent effect. The enzymatic degradation of these HA nanoparticles was then evaluated with twohyaluronidases: HYAL1 and SPAM-1. The digestion of the HA nanoparticles was significantly slower than that of free hyaluronic acid. Surprisingly, these HA nanoparticles could even inhibit the activity of the enzyme HYAL1 and protect free HA chains in the solution. Finally, lipopeptide-based ligands of the biological receptor TLR2 were also synthesized and their performances were evaluated by SPR.
204

Desenvolvimento e caracterização de novos materiais destinados à liberação modificada de ativos farmacoterapêuticos / Development and characterization of new materials for the modified release of pharmacotherapeutic agents

Sgorla, Débora 03 February 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2017-08-30T19:45:54Z No. of bitstreams: 4 Débora Sgorla.pdf: 1749128 bytes, checksum: e687399f0ee2e0ef0bf64d945ededc36 (MD5) ANEXO A – Artigo publicado - Development and characterization of crosslinked hyaluronic acid polymeric films for use in c~1.pdf: 2607800 bytes, checksum: f08233b805a21000ec3bd1134155499e (MD5) ANEXO B – Artigo publicado - Exploitation of lipid-polymeric matrices at nanoscale for drug delivery applications.pdf: 1272400 bytes, checksum: 817f7d9360bbc82b4da1596089608c18 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-30T19:45:54Z (GMT). No. of bitstreams: 4 Débora Sgorla.pdf: 1749128 bytes, checksum: e687399f0ee2e0ef0bf64d945ededc36 (MD5) ANEXO A – Artigo publicado - Development and characterization of crosslinked hyaluronic acid polymeric films for use in c~1.pdf: 2607800 bytes, checksum: f08233b805a21000ec3bd1134155499e (MD5) ANEXO B – Artigo publicado - Exploitation of lipid-polymeric matrices at nanoscale for drug delivery applications.pdf: 1272400 bytes, checksum: 817f7d9360bbc82b4da1596089608c18 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Introduction: Progress in the release of pharmacotherapeutic agents and improved quality of life for patients depends on the development of novel and suitable drug delivery systems because a number of conventional pharmaceutical forms can trigger multiple side effects as well as inconvenient administrations, which ultimately lead to poor treatment adhesions or inefficient treatments. Objectives: To develop new materials for application in modified drug release systems, whose potential uses are for coating solid oral dosage forms and insulin encapsulation for oral administration. Methodology: Coating films: Initially, hyaluronic acid was crosslinked with trisodium trimetaphosphate in aqueous alkaline media. Afterwards, the films were produced by evaporation method by incorporation of the unmodified and crosslinked biopolymer into the ethylcellulose dispersion in different proportions. The obtained films were characterized by morphology by scanning electron microscopy, robustness to water vapor permeability and hydration capacity in physiological simulation fluids. In addition, safety and biocompatibility were evaluated against Caco-2 and HT29-MTX intestinal cells. Lipid-polymeric nanoparticles: They were produced from the association of ethylpalmitate and HPMC-AS, through the modified solvent emulsification-evaporation technique by sonication. Subsequently, the nanoparticles were characterized by size, polydispersity index, zeta potential and encapsulation efficiency, besides morphology by scanning electron microscopy, X-ray diffraction and thermal analysis. It was also evaluated the in vitro release profile, as well as insulin uptake in a triple co-culture model, and safety and biocompatibility against Caco-2 and HT29-MTX intestinal cells. Results: Coating films: The permeability to water vapor was influenced by the increase of hyaluronic acid content in the final formulation. When immersed in gastric simulation fluid, the films presented lower swelling compared to greater hydration in intestinal simulation fluid. Simultaneously, in intestinal simulation fluid, they presented mass loss, revealing the ability to prevent premature drug release at gastric pH, yet vulnerable to release into the intestinal environment. In addition to these results, the physico-chemical characterization suggested thermal stability of the films and physical interaction between the constituents of the formulation. Finally, cytotoxicity tests demonstrated viii that both membranes and individual materials were safe for intestinal cells when incubated for 4 h. Lipid-polymer nanoparticles: The suggested methodology yielded nanoparticles with satisfactory mean size, 297.57nm ± 29.99, PDI of 0.247 ± 0.03 and zeta potential of -19.13 ± 5.88. In addition, high encapsulation efficiency was achieved, around 83.92 ± 4.32% and DSC showed an improvement in the thermal stability of the formulation compared to individual materials. This is demonstrated by endothermic peaks of degradation that decreased in intensity and moved to higher temperatures. DRX results showed alteration of the crystalline state to amorphous, inferring the drug incorporation. The cumulative release demonstrated that only 9.0% of the encapsulated insulin was released after 2 h, reaching approximately 14% after 6h. These results altered the permeability of insulin through in vitro intestinal model. Regarding the biocompatibility with Caco-2 and HT29-MTX cells, lipid-polymeric nanoparticles did not show toxicity up to 4 hours. Conclusions: The results suggest that hyaluronic acid based films may prevent premature drug release under hostile conditions of the stomach but control the release in the more distal portions of the gastrointestinal tract when applied as coating material in solid oral dosage forms. Furthermore, they were safe to intestinal mucosa. Regarding the lipid-polymeric nanoparticles, evidences show that they can protect insulin from the hostile conditions found in the TGI, also guaranteeing the safety of the intestinal mucosa depending on its concentration. However, a better release profile and consequently better insulin uptake can be achieved by optimizing the proposed formulation. / Introdução: O progresso na liberação de ativos farmacoterapêuticos e uma melhor qualidade de vida aos pacientes depende do desenvolvimento de novos e adequados sistemas carreadores de fármacos, visto que diversas formas farmacêuticas convencionais podem desencadear múltiplos efeitos colaterais bem como administrações inconvenientes, que acabam por conduzir a fracas adesões de tratamento ou tratamentos ineficientes. Objetivos: Desenvolver novos materiais candidatos à aplicação em sistemas para liberação modificada de fármacos, cujos empregos potenciais estão voltados ao revestimento de formas farmacêuticas sólidas orais e encapsulação de insulina para administração oral. Metodologia: Filmes de revestimento: Inicialmente o ácido hialurônico foi reticulado com trimetafosfato trissódico em meio aquoso alcalino, posteriormente, os filmes foram produzidos através do método de evaporação, por incorporação do biopolímero reticulado e não modificado à dispersão de etilcelulose, em diferentes proporções. As películas obtidas foram caracterizadas em relação à morfologia por microscopia eletrônica de varredura, robustez à permeabilidade ao vapor d’água e capacidade de hidratação em fluidos de simulação fisiológicos. Além disso, a segurança e biocompatibilidade foram avaliadas contra células intestinais Caco-2 e HT29-MTX. Nanopartículas lipídico-poliméricas: Foram produzidas a partir da associação de etilpalmitato e HPMC-AS, por meio da técnica emulsificação-evaporação do solvente modificado, através de sonicação. Posteriormente, as nanopartículas foram caracterizadas em relação ao tamanho, índice de polidispersão, potencial zeta e eficiência de encapsulação, além de morfologia por microscopia eletrônica de varredura, difratometria de raios-X e análise térmica. Também avaliou-se o perfil de liberação in vitro, bem como a captação da insulina em modelo de co-cultura tripla e, segurança e biocompatibilidade contra células intestinais Caco-2 e HT29-MTX. Resultados: Filmes de revestimento: A permeabilidade ao vapor d’água foi influenciada pelo aumento do conteúdo de ácido hialurônico na formulação final. Quando imersos em fluido de simulação gástrico, os filmes apresentaram menor intumescimento comparado com uma maior hidratação em fluido de simulação intestinal. Simultaneamente, em fluido de simulação intestinal, apresentaram perda vi de massa, revelando a habilidade de prevenir a liberação prematura do fármaco em pH gástrico, todavia vulnerável a liberação em meio intestinal. Aliado a estes resultados, a caracterização físico-química sugeriu estabilidade térmica das películas e interação física entre os constituintes da formulação. Por fim, os testes de citotoxicidade demonstraram que tanto as membranas quanto os componentes individuais das formulações, quando incubadas durante 4 h, foram seguras para as células intestinais. Nanopartículas lipídico-poliméricas: A metodologia sugerida produziu nanopartículas com tamanho médio satisfatório, 297,57nm ± 29,99, PDI de 0,247 ± 0,03 e potencial zeta de -19,13 ± 5,88. Além disso, alcançou-se alta eficiência de encapsulação, em torno de 83,92 ± 4,32% e o DSC mostrou um aumento da estabilidade térmica das formulações em relação aos materiais puros, demonstrado pelos picos endotérmicos de desidratação, que diminuíram de intensidade e deslocaram-se para temperaturas superiores. Os resultados do DRX demonstraram alteração do estado cristalino para amorfo, inferindo a incorporação do fármaco. A liberação cumulativa evidenciou que apenas 9% da insulina encapsulada foi liberada após 2 h, alcançando aproximadamente 14% após 6 h, alterando, desta maneira, os resultados de permeabilidade da insulina através de modelo intestinal in vitro. Em relação à biocompatibilidade com células Caco-2 e HT29-MTX, as nanopartículas lipídico-poliméricas demonstraram ausência de citotoxicidade após 4 h. Conclusões: Os resultados sugerem que os filmes baseados em ácido hialurónico, quando aplicados como material de revestimento de formas farmacêuticas sólidas orais, poderão prevenir a liberação prematura de fármacos nas condições hostis do estômago, mas controlar a liberação nas porções mais distais do trato gastrointestinal, garantindo a segurança da mucosa intestinal. Já em relação às nanopartículas lipídico-poliméricas, evidências demonstraram que as mesmas poderão proteger a insulina das condições hostis encontradas no TGI, garantindo ainda a segurança da mucosa intestinal, todavia um melhor perfil de liberação, e consequentemente, uma melhor captação insulina podem ser alcançados por otimização da formulação proposta.
205

Relevância dos proteoglicanos como biomarcadores prognósticos e preditivos em carcinomas não-pequenas células e seu impacto na carcinogênese pulmonar / Clinical relevance of matrix proteoglycans as predictors of lung cancer patients outcome

Maristela Peres Rangel 12 December 2016 (has links)
Introdução. Os glicosaminoglicanos e os proteoglicanos são moléculas abundantes na matriz extracelular. Vários estudos têm demonstrado que uma produção ou degradação aberrante dessas moléculas tem influência no comportamento do câncer de mama, cólon e pâncreas. Outras proteínas como o solCD44 e a cofilina-1 também tem demonstrado influência direta na progressão dos tumores. Desta forma, a análise da expressão destas moléculas em tecidos e fluidos corporais tem despertado grande interesse como rastreador de indivíduos de alto risco e marcador diagnóstico e/ou prognóstico da doença. Objetivos. Conhecer o impacto do ácido hialurônico e dos proteoglicanos (biglicam, glipicam, perlecam, sindecam e versicam) na carcinogênese bem como seu impacto na sobrevida dos pacientes; verificar se a concentração de solCD44 e cofilina-1 presente no escarro de pacientes com câncer de pulmão permite rastreá-los entre pacientes com doença pulmonar obstrutiva crônica e voluntários saudáveis. Resultados. Uma associação significativa direta foi encontrada entre os tumores com alto percentual de expressão de AH e de microvasos no estroma tumoral. As concentrações de heparam e condroitim sulfato nas amostras tumorais foram mais elevadas quando comparadas às amostras não tumorais. Com exceção do sindecam, todos os outros proteoglicanos apresentaram uma expressão gênica significativamente menor nos tecidos tumorais e biglicam e versicam apresentaram associações com as características clinico patológicas. A expressão proteica de biglicam, perlecam e versicam foi significativamente maior no tecido normal do que nas áreas de estroma tumoral e de células tumorais. Pela análise de regressão de COX controlada para idade, tipo histológico e expressão gênica de biglicam, sindecam e glipicam obtiveram alta taxa de sobrevida os pacientes do sexo feminino com elevada expressão gênica de perlecam e menor risco de óbito em estadio T1, ausência de metástases nodais e expressão gênica de versicam. A Maristela Peres Rangel Tese de doutorado - USP concentração de cofilina demonstrou-se mais elevada no escarro de pacientes com câncer de pulmão quando comparado ao escarro de pacientes de alto risco e de voluntários saudáveis. A concentração de solCD44 também demonstrou-se mais elevada no escarro de pacientes com câncer de pulmão quando comparado ao escarro de pacientes de alto risco e de voluntários saudáveis. Através da curva ROC, a cofilina-1 presente no escarro foi capaz de distinguir os pacientes de alto risco dos pacientes com câncer de pulmão com área abaixo da curva de 0.69 e com um ponto de corte de 802.5 pg/mL a curva apresentou 60% de sensibilidade e 54% de especificidade. O solCD44 presente no escarro também foi capaz de distinguir os pacientes de alto risco dos pacientes com câncer de pulmão através da curva ROC com área abaixo da curva de 0.67 e com um ponto de corte de 65.8 pg/mL a curva apresentou 50% de sensibilidade e 84% de especificidade. Conclusão. A expressão do ácido hialurônico demonstrou ter correlação no processo de crescimento tumoral através da angiogênese. A análise biomolecular apontou a diminuição dos proteoglicanos no tecido tumoral e, portanto, estes podem ser potenciais biomarcadores prognósticos de câncer de pulmão. As análises feitas em escarro demonstraram que a elevada expressão proteica de solCD44 e da cofilina-1 no escarro nos pacientes com câncer de pulmão mostram-se como promissores alvos de detecção do CP / Introduction. The relationship between the extracellular matrix (ECM) components and cancer cells have an important role on cancer development and progression. Between the most important molecules present on the ECM are the glycosaminoglycans and their respective proteoglycans. Studies have reported that they have different behaviours when in the presence of malignant tissues and influence the development of breast, pancreas and colon cancers. Likewise, proteins as solCD44 and cofilin-1 also have shown direct influence in tumor progression. Regarding that, there is growing interest among scientists in analyzing the expression of these molecules in body fluids as a screening tool of high risk patients and as a diagnostic and prognostic lung cancer biomarker. Objectives. The aims of this study were to recognize the impact of hyaluronan and the proteoglycans (biglycan, glypican, perlecan, syndecan e versican) on lung cancer carcinogenesis as well as its impact on patient\'s survival; verify if the solCD44 e cofilina-1 concentrations in the sputum of lung cancer patients could distinguish them from patients with COPD and healthy volunteers. Results. A direct association was found between tumors expressing high amounts of hyaluronan and CD34 in tumoral stroma. Heparan and chondroitin sulphate concentrations were higher in tumor specimens when compared to normal lung tissue. All proteoglycans, in exception of syndecan, showed a lower expression in tumoral tissue and biglycan and versican showed association with the clinical pathological features. Protein expression of biglycan, perlecan and versican was higher in the normal tissue when compared to stroma and tumoral cells. COX regression controlled by age, histological types and gene expression of biglycan, syndecan e glypican demonstrated that female patients had higher survival rates with high gene expression of perlecan and the patients with T1 stage, lack of linfonode Maristela Peres Rangel Tese de doutorado - USP metastasis and gene expression of versican had lower risk of death. Cofilin-1 concentration was higher in the sputum of lung cancer patients when compared to a high risk group and healthy volunteers. Also, the solCD44 concentration was higher in the sputum of lung cancer patients when compared to a high risk group and healthy volunteers. ROC cruve analysis demonstrated that sputum cofilin-1 was capable to distinguish high risk patients from lung cancer patients with na area under the curve of 0.69 and with a cut off at 802.5 pg/mL the curve presented 60% de sensitivity and 54% specificity. Sputum solCD44 was also capable to distinguish high risk patients from lung cancer patients with na area under the curve of 0.67 and with a cut off at 65.8 pg/mL the curve presented 50% de sensitivity and 84% specificity. Conclusions. Hyaluronan expression showed a correlation with tumoral growth through angiogenesis processes. The biomolecular analysis demonstrated that matrix proteoglycans are potencial lung cancer prognostic biomarkers. Sputum analyses showed that solCD44 and cofilin-1 are potencial molecules in lung cancer detection
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Hyaluronic acid hydrogel materials

Zawko, Scott Andrew 02 February 2011 (has links)
Hyaluronic acid (HA) is one of the primary chemical building blocks of the extracellular matrix and thus is an attractive material for biomedical applications. FDA approved HA-based materials are available as dermal fillers, joint viscosupplements, vitreous substitutes, and abdominal adhesion barriers. The engineering of new HA-based materials and applications is an active area of research. Here we develop several new types of HA-based hydrogels with unique and useful properties. To address the challenge of delivering hydrophobic drugs from hydrophilic hydrogel matrices we have grafted HA hydrogels with [Beta]-cyclodextrin to create hydrogels capable of binding poorly water soluble drugs. To create HA hydrogels with unique anisotropic swelling behavior we have developed a dual-crosslinking technique in which a super-swelling chemically crosslinked hydrogel is patterned with low-swelling photocrosslinked domains. When this dual-crosslinked hydrogel is swelled it contorts into a new shape because of differential swelling among photopatterned regions. To address the challenge of creating hydrogel scaffolds with biomimetic branched porosity we have invented a "crystal templating" technique. This technique grows dendritic crystals throughout a biopolymer solution, crosslinks the biopolymer around the crystals, and washes the crystals away to yield a hydrogel with a dendritic macroporous network. Lastly, we invented a method for patterning a substrate with a microarray of hydrogel compartments. A microarray of living cells is obtained when cells are seeded on the hydrogel patterned substrate. This method addresses the need for an inexpensive, simple method for obtaining living cell microarrays that does not require clean room labs and lithographic expertise. Each of these new materials were based on hyaluronic acid hydrogels but the methods are generalizable to hydrogels of other polymers too. In conclusion, the novel methods in this dissertation are a significant contribution to the engineering of HA-based materials. / text
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Ex vivo investigation of novel wound healing therapies and development of a 3-D human skin equivalent wound model

Xie, Yan January 2008 (has links)
It has previously been found that complexes comprised of vitronectin and growth factors (VN:GF) enhance keratinocyte protein synthesis and migration. More specifically, these complexes have been shown to significantly enhance the migration of dermal keratinocytes derived from human skin. In view of this, it was thought that these complexes may hold potential as a novel therapy for healing chronic wounds. However, there was no evidence indicating that the VN:GF complexes would retain their effect on keratinocytes in the presence of chronic wound fluid. The studies in this thesis demonstrate for the first time that the VN:GF complexes not only stimulate proliferation and migration of keratinocytes, but also these effects are maintained in the presence of chronic wound fluid in a 2-dimensional (2-D) cell culture model. Whilst the 2-D culture system provided insights into how the cells might respond to the VN:GF complexes, this investigative approach is not ideal as skin is a 3-dimensional (3-D) tissue. In view of this, a 3-D human skin equivalent (HSE) model, which reflects more closely the in vivo environment, was used to test the VN:GF complexes on epidermopoiesis. These studies revealed that the VN:GF complexes enable keratinocytes to migrate, proliferate and differentiate on a de-epidermalised dermis (DED), ultimately forming a fully stratified epidermis. In addition, fibroblasts were seeded on DED and shown to migrate into the DED in the presence of the VN:GF complexes and hyaluronic acid, another important biological factor in the wound healing cascade. This HSE model was then further developed to enable studies examining the potential of the VN:GF complexes in epidermal wound healing. Specifically, a reproducible partial-thickness HSE wound model was created in fully-defined media and monitored as it healed. In this situation, the VN:GF complexes were shown to significantly enhance keratinocyte migration and proliferation, as well as differentiation. This model was also subsequently utilized to assess the wound healing potential of a synthetic fibrin-like gel that had previously been demonstrated to bind growth factors. Of note, keratinocyte re-epitheliasation was shown to be markedly improved in the presence of this 3-D matrix, highlighting its future potential for use as a delivery vehicle for the VN:GF complexes. Furthermore, this synthetic fibrin-like gel was injected into a 4 mm diameter full-thickness wound created in the HSE, both keratinocytes and fibroblasts were shown to migrate into this gel, as revealed by immunofluorescence. Interestingly, keratinocyte migration into this matrix was found to be dependent upon the presence of the fibroblasts. Taken together, these data indicate that reproducible wounds, as created in the HSEs, provide a relevant ex vivo tool to assess potential wound healing therapies. Moreover, the models will decrease our reliance on animals for scientific experimentation. Additionally, it is clear that these models will significantly assist in the development of novel treatments, such as the VN:GF complexes and the synthetic fibrin-like gel described herein, ultimately facilitating their clinical trial in the treatment of chronic wounds.
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Eficiência do protocolo superestimulatório P-36 com a utilização de duas administrações de FSH, em animais da raça angus (Bos taurus) / Efficiency protocol superstimulatory P-36 with the use of two FSH administration in Angus cows (Bos taurus)

Bonotto, Ramiro Martins 16 December 2015 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-02-15T15:54:41Z No. of bitstreams: 1 PGCA15MA186.pdf: 990652 bytes, checksum: cbcaededf568083c37a57ea2fa505e9f (MD5) / Made available in DSpace on 2018-02-15T15:54:41Z (GMT). No. of bitstreams: 1 PGCA15MA186.pdf: 990652 bytes, checksum: cbcaededf568083c37a57ea2fa505e9f (MD5) Previous issue date: 2015-12-16 / PROMOP / Embryo transfer is a biotechnology widely used in Bos taurus cows. This principle involves making an over stimulation protocol for inducing multiple ovulations. The P-36 protocol is one of the most used for this purpose as it allows artificial insemination in fixed time (TAI) facilitating the management of donor and recipient embryo. The overstimulation is made with eight pFSH decreasing doses every 12 hours, but studies show that the administration pFSH with a slow absorption decreases the number of applications, maintaining output similar embryos. So the aim of this study was to compare the superovulation of cows using the P36 protocol with reduction in the number of handlings. They were used 24 donor cows of Angus, randomly assigned to two groups: Control and MAP-5 (hyaluronic acid), in a crossover design. At random stage of the estrous cycle (D0), donors received an intravaginal device containing 1.0 g progesterone (DIV) and estradiol benzoate (2 mg, IM). In the control group, the animals were over stimulated with pFSH (IM, total dose = 200 mg) twice daily in decreasing doses of D4 to D7, while the MAP-5 group were carried out only two administrations in the D4 (75% of dose) and D6 (25% of dose). The embryo collections were made in the protocol D15. Statistical analysis was performed with SAS statistical package using the Mixed procedure with 5% significance level, and the variables considered: number of follicles on the day of ovulation induction, the number of corpora lutea at collection time, total number of collected structures, structures and number of fertilized number of viable embryos. The control group showed significantly better than the MAP-5 group and the number of follicles (10.08 ± 0.61 vs. 8.25 ± 0.61), corpora lutea (7.25 ± 0.59 vs. 3.25 ± 0.59) which resulted in a 71.90% ovulation rate for the control group and 39.39% for the MAP-5 group. As for the total number of structures (8.29 ± 0.98 vs. 3.08 ± 0.98), fertilized structures (6.50 ± 0.90 vs. 2.50 ± 0.90) and viable embryos (4 21 ± 0.72 vs. 2.00 ± 0.72) the control group also showed a significant difference when compared to MAP-5. This shows that the reduction of handlings with 200 mg of FSH proposed with MAP-5 group was not effective donor Angus breed / A transferência de embriões é uma biotecnologia amplamente utilizada em vacas Bos taurus. Este princípio envolve a realização de um protocolo de superestimulação para indução de ovulações múltiplas. O protocolo P-36 é um dos mais utilizados com este propósito, pois permite a inseminação artificial em tempo fixo (IATF) facilitando o manejo de doadoras e receptoras de embriões. A superestimulação é feita com oito doses decrescentes de pFSH a cada 12h, porém estudos mostram que a administração de pFSH com uma absorção lenta diminui o número de aplicações, mantendo a mesma produção de embriões. Assim o objetivo deste trabalho foi comparar a superovulação de vacas utilizando o protocolo P36 com redução no número de manejos. Foram utilizadas 24 vacas doadoras da raça Angus, distribuídas aleatoriamente em 2 grupos: Controle e MAP-5 (ácido hialurônico), em um delineamento cross over. Em dia aleatório do ciclo estral (D0), as doadoras receberam um dispositivo intravaginal contendo 1,0 g de progesterona (DIV) e benzoato de estradiol (2 mg, via IM). No grupo controle, os animais foram superestimulados com pFSH (via IM, dose total = 200 mg) duas vezes ao dia em doses decrescentes do D4 ao D7, enquanto que no grupo MAP-5 foram realizadas somente duas administrações no D4 (75% da dose) e D6 (25% da dose). As coletas de embriões foram realizadas no D15 do protocolo. A análise estatística foi realizada com o pacote estatístico SAS utilizando o procedimento Mixed com nível de significância a 5%, sendo consideradas as variáveis: número de folículos no dia da indução de ovulação, número de corpos lúteos no momento da coleta, número de estruturas totais coletadas, número de estruturas fertilizadas e número de embriões viáveis. O grupo controle demonstrou-se significativamente melhor que o grupo MAP-5 quanto ao número de folículos (10,08±0,61 vs. 8,25±0,61), corpos lúteos (7,25±0,59 vs. 3,25±0,59) o que resultou em uma taxa de ovulação de 71,90% para o grupo controle e 39,39% para o grupo MAP-5. Quanto ao número de estruturas totais (8,29±0,98 vs. 3,08±0,98), estruturas fertilizadas (6,50±0,90 vs. 2,50±0,90) e embriões viáveis (4,21±0,72 vs. 2,00±0,72) o grupo controle também demonstrou diferença significativa quando comparado ao MAP-5. O que demonstra que a redução dos manejos com a dose de 200 mg de FSH proposta como grupo MAP-5 não foi eficaz para doadoras da raça Angus
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Chirurgie des troubles de la statique pelvienne et des hernies avec interposition de prothèses de renfort. / Surgery of pelvic disorders and hernias with interposition of reinforcement prostheses.

Nohuz, Erdogan 16 September 2013 (has links)
Introduction : L’allongement de l’espérance de vie, qui a pour corollaire le vieillissement de la population, laisse présager d’un recours croissant au renfort prothétique en chirurgie des troubles de la statique pelvienne et pariétale. Actuellement, en uro-gynécologie, l’utilisation des prothèses de synthèse est communément admise pour l’abord abdominal (cœlioscopique ou laparotomique) alors même que la voie vaginale est sujette à d’innombrables controverses. La rétraction prothétique représente un réel problème iatrogène, source de douleurs, d’érosion et de récidive, quelle que soit la voie d’abord utilisée. Il s’agit d’une complication sérieuse et, à l’heure actuelle, la moins documentée. L’étiopathogénie de cette rétraction reposerait sur les phénomènes adhérentiels de l’hôte, en réponse au matériau implanté (« contraction passive »). Objectifs : - Rechercher une solution à la rétraction prothétique. Le postulat de départ de cette thèse pose le fait que l’adjonction d’un gel ou d’un film d’acide hyaluronique, connus pour leur efficacité dans la diminution des adhérences post-opératoires, préviendrait la rétraction d’un implant en polypropylène chez la rate.- Établir un état des lieux, au lendemain des recommandations alarmistes américaines, mais plus nuancées et rassurantes de la part de nos sociétés savantes et experts européens vis-à-vis du recours au renfort prothétique en chirurgie vaginale.Matériels et méthodes : au décours d’une revue de la littérature, un modèle expérimental a été élaboré. Soixante rates ont été randomisées en 3 groupes. Un défect herniaire standard a été induit par laparotomie médiane au niveau de la paroi abdominale antérieure puis réparé par l’utilisation d’une prothèse en polypropylène de faible grammage macroporeux seule (groupe 1), avec application d’un film (groupe 2) ou avec enduction prothétique d’un gel (groupe 3) d’acide hyaluronique. Huit semaines après la procédure, une nouvelle laparotomie a été réalisée permettant l’évaluation d’un score adhérentiel et des surfaces prothétiques. Une étude histologique microscopique de l’interface hôte-tissu a également été effectuée.Résultats : Le groupe 1 (groupe contrôle), présentait un taux de rétraction prothétique de 29%. Les groupes 2 (p=0.0238) et 3 (p=0.0072) présentaient des taux de rétraction significativement plus bas, respectivement de 19.12% (groupe film) et 17% (groupe gel). La différence entre les 3 groupes était statistiquement significative (p=0.0153). Les adhérences post-opératoires étaient significativement moins importantes dans les groupes utilisant l’acide hyaluronique. Le groupe 1 présentait significativement un score adhérentiel plus élevé (30.40) que les groupes 2 (11.67, p=0.0028) et 3 (11.19, p=0.0013). La colonisation conjonctivale était moins intense dans le groupe gel, comparativement aux groupes film et témoin (p=0.0181).Conclusion et perspectives cliniques : Notre travail expérimental a démontré que la surface prothétique était sauvegardée de façon statistiquement significative lors du recours à un gel ou un film d’acide hyaluronique La rétraction prothétique, compliquant la chirurgie avec implant synthétique en polypropylène, pourrait être prévenue par l’adjonction de ce complément. Ceci préviendrait la formation d’adhérences post-opératoires et de fibrose, propices à la contraction du tissu hôte péri-prothétique et conduisant à la rétraction du matériau de renfort. Cette donnée devrait être intégrée dans une stratégie de sauvegarde prothétique préservant la qualité ainsi que la durée de la réparation chirurgicale tout en limitant la douleur post-opératoire. / IntroductionThe prolongation of life expectancy, which has for corollary the aging of the population, leads to predict of a growing appeal to the use of prosthetic reinforcement in surgery for pelvic statics’ disorders and parietal hernias. Currently, in uro-gynecology, the use of synthetic meshes is commonly admitted for the abdominal approach (by laparoscopy or laparotomy) while the vaginal route is subject to innumerable controversies. Prosthetic retraction (shrinkage) represents a real iatrogenic problem, causing pain, erosion and recurrence, whatever the approach used. This is a serious complication and, at the moment, the least documented. The etiopathogenesis of this retraction is based on host adhesion phenomena, in response to the implanted material ("passive contraction").Objectives-To research for a solution to prosthetic retraction. The basic premise of this thesis puts the fact that the addition of a gel or a film of hyaluronic acid, known for their effectiveness in reducing post-operative adhesions, would prevent the retraction of a polypropylene implant in a rat model.-To establish an update, the day after the American alarmist recommendations, but more nuanced and reassuring on behalf of our learned societies and European experts with regard to prosthetic reinforcement ‘use in vaginal surgery.Material and methods :Following a review of the literature, an experimental model was developed. Sixty rats were randomized into 3 groups. A standard hernial defect was induced by medial laparotomy in the anterior abdominal wall and then repaired using a macroporous low weight polypropylene mesh alone (group 1), with application of a film (group 2) or coating of a gel (group 3) of hyaluronic acid. Eight weeks after the procedure, a new laparotomy was realized to evaluate an adhesion score and prosthetic surfaces. A microscopic histological study of the host-tissue interface was also performed.Results :Group 1 (control group) had a mesh retraction rate of 29%. Groups 2 (p = 0.0238) and 3 (p = 0.0072) had significantly lower retraction rates, respectively 19.12% (film group) and 17% (gel group). The difference between the 3 groups was statistically significant (p = 0.0153). Post-operative adhesions were significantly less important in groups using hyaluronic acid. Group 1 had a significantly higher adherence score (30.40) than groups 2 (11.67, p = 0.0028) and 3 (11.19, p = 0.0013). Conjunctival colonization was less intense in the gel group, compared to the control and film groups (p = 0.0181).Conclusion and clinical perspectives :Our experimental study has shown that the prosthetic surface is protected in a statistically significant way when using a gel or film of hyaluronic acid. Mesh shrinkage, complicating surgery with synthetic polypropylene implant, could be prevented by the addition of this complement. This would prevent the formation of postoperative adhesions and fibrosis, which are conducive to contraction of the periprosthetic host tissue and leading to retraction of the reinforcing material. This data should be incorporated into a prosthetic safeguard strategy that preserves the quality as well as the duration of surgical repair while limiting post-operative pain.
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Uso de ácido hialurônico associado ao plasma rico em plaquetas na regeneração de defeitos do disco articular e da superfície osteocondral causados pela osteoartrite na ATM / Use of hyaluronic acid associated with platelet rich plasma in the regeneration of defects of the articular disc and the osteochondral surface caused by osteoarthritis in the TMJ

Ankha, Milagros del Valle El Abras [UNESP] 07 February 2018 (has links)
Submitted by MILAGROS DEL VALLE EL ABRAS ANKHA (doc_elabras@hotmail.com) on 2018-04-19T00:51:40Z No. of bitstreams: 1 Milagros Abras Ankha-tese final 2018 com ficha catolográfica.pdf: 3661703 bytes, checksum: 64be3370b9106d7afd83981f08a49a3e (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-04-25T22:49:50Z (GMT) No. of bitstreams: 1 elabrasankha_mdv_dr_sjc.pdf: 3661703 bytes, checksum: 64be3370b9106d7afd83981f08a49a3e (MD5) / Made available in DSpace on 2018-04-25T22:49:50Z (GMT). No. of bitstreams: 1 elabrasankha_mdv_dr_sjc.pdf: 3661703 bytes, checksum: 64be3370b9106d7afd83981f08a49a3e (MD5) Previous issue date: 2018-02-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Estudos anteriores sugerem que o ácido hialurônico (AH) e o plasma rico em plaquetas (PRP) têm potencial para melhorar o processo de cicatrização da cartilagem e diminuir a progressão da osteoartrite. No entanto, poucas pesquisas avaliam seu efeito sinérgico. Este trabalho tem como objetivo avaliar o efeito do AH associado ao PRP na regeneração do disco articular e da superfície osteocondral da articulação temporomandibular (ATM). A osteoartrite será induzida por meio da perfuração bilateral do disco articular de coelhos. Quarenta coelhos foram divididos em 4 grupos, conforme o procedimento: sem lesão(SL)/sem tratamento(ST) (n=4), lesão(L)/sem tratamento (ST) (n=12), L/AH (n=12), L/AH+PRP (n=12). Quatro coelhos do grupo SL/ST foram eutanasiados no tempo zero. Após 8 e 24 semanas da perfuração dos discos articulares, seis coelhos dos grupos L/ST, L/AH e L/AH+PRP foram eutanasiados. O disco articular foi avaliado radiograficamente para visualizar possíveis calcificações. Foi realizada análise macroscópica e histológica do disco e do côndilo mandibular. Foi utilizada a análise histoquímica por Picrosirius Red para avaliar a presença de colágeno I e III e a análise imuno-histoquímica do colágeno I e II. As porcentagens de marcação obtidas nas análises histoquímica e imuno-histoquímica foram avaliadas estatisticamente, adotando-se o nível de significância de 5%. Macroscopicamente, o disco articular nos grupos tratados apresentou, na maioria dos espécimes, preenchimento parcial ou total do defeito criado. Os côndilos apresentaram, na maioria dos espécimes, irregularidade da superfície osteocondral. Radiograficamente, após 24 semanas da perfuração do disco, focos de radiopacidade foram observados nos grupos não tratados e em alguns dos espécimes dos tratados. Na análise histológica foi confirmada a presença de material mineralizado, próximo e distante da perfuração, além de diminuição da celularidade e fibrose. Na análise histoquímica, a porcentagem de colágeno I prevaleceu com relação ao colágeno III, tanto no disco quanto no côndilo, independentemente do grupo e período avaliado. Entretanto, no disco não houve diferença estatística significativa. No côndilo, L/AH e L/AH+PRP nos períodos de 8 e 24 semanas apresentaram uma porcentagem de colágeno I significativamente maior que L/ST (p<0,05). A expressão imuno-histoquímica de colágeno I e II no disco não apresentou diferença estatística significante. No côndilo, a expressão do colágeno I apresentou diferença significativa entre os 9 grupos (p=0,00) e os períodos (p=0,05). O grupo L/AH+PRP de 24 semanas apresentou maior porcentagem de marcação positiva para colágeno I, que era diferente dos grupos SL/ST e L/ST, porém sem diferença estatística com relação ao L/AH. Em conclusão, os tratamentos da osteoartrite com AH ou PRP associado ao AH mostram resultados promissores, ajudando na redução do defeito criado no disco, porém, sem resultados satisfatórios como protetores da superfície osteocondral, na presença de perfuração discal. / Previous studies have suggested that hyaluronic acid (HA) and platelet-rich plasma (PRP) have the potential to improve the healing process of cartilage and decrease the progression of osteoarthritis. However, few studies have evaluated their synergistic effect. This study aims at evaluating the effect of HA associated with PRP on the regeneration of the articular disc and the osteochondral surface of the temporomandibular joint (TMJ). Osteoarthritis was induced by means of bilateral perforation of the articular disc of rabbits. Forty rabbits were divided into 4 groups, according to the procedure: without lesion (WL)/without treatment (WT) (n = 4), lesion (L)/without treatment (WT) (n = 12), L/HA (n = 12), L/ HA+PRP (n = 12). Four rabbits from group G1 were euthanized at time zero. After 8 and 24 weeks of joint disc perforation, six rabbits from groups L/WT, L/HA and L/HA+PRP were euthanized. The articular disc was evaluated radiographically to visualize possible calcifications. Macroscopic and histological analysis of the disc and the mandibular condyle were performed. The histochemical analysis by Picrosirius Red was used to evaluate the presence of collagen I and III, as well as the immunohistochemical analysis was used to evaluate the expression of collagen I and II. The percentages of staining obtained from the histochemical and immunohistochemical analysis were statistically evaluated, adopting the significance level of 5%. Macroscopically, the articular disc in the treated groups presented in most of the specimens partial or total filling of the defect created. The condyles presented, in most of the specimens, degeneration of the osteochondral surface. Radiographically, after 24 weeks of disc perforation, foci of radiopacity were observed in the untreated and in some of the specimens of treated groups. Histological analysis confirmed the presence of mineralized material, close and distant to perforation, as well as decreased cellularity and fibrosis. In the histochemical analysis, the percentage of collagen I prevailed in both disc and condyle, independently of the group and period evaluated. However, in the disc there was not statistical difference. In the condyle, L/HA and L/HA+PRP in the periods of 8 and 24 weeks presented a percentage of collagen I significantly higher than L/WT (p <0.05). The expression of collagen I and II in the disc did not present significant statistical difference. In the condyle, the expression of collagen I was statistically different between the groups (p = 0.00) and the periods (p = 0.05). The 24-week L/HA+PRP group had a higher percentage of positive marking for collagen I, which was different from the WL/WT and L/WT groups, but with no statistical difference with respect to L/HA. In conclusion, the treatment of osteoarthritis with HA or PRP associated with HA shows promising results, helping to reduce the defect created in the disc, but without satisfactory results as protectors of the osteochondral surface, in the presence of perforation of the disc. / 2016/23446-2

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