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O perfil de expressão dos MiRNAs reguladores de CD44 e das sintases do ácido hialurônico no câncer de próstata / The expression profile of miRNAs regulatory of CD44 and hyaluronic acid synthases in prostate cancerMoura, Caio Martins 27 October 2017 (has links)
Introdução: O Câncer de próstata (CaP) é o tumor sólido mais comum e a segunda causa de óbito por câncer no homem em países ocidentais. Caracteristicamente tem comportamento heterogêneo e os fatores prognósticos falham na previsão de sua agressividade. Assim, existe a necessidade da busca de novos marcadores moleculares que melhorem a definição prognóstica. Em estudo prévio demonstramos que a perda de expressão da molécula de adesão CD44 padrão (CD44s) e superexpressão das variantes do CD44 (CD44v) são características do CaP localizado. O CD44 tem como principal ligante o ácido hialurônico (AH), principal componente da matriz extracelular, sintetizado pelos genes has2 e has3. Talvez microRNAs (miRNA) regulem a expressão destes genes no CaP. Objetivo: Nosso objetivo foi analisar o perfil de expressão dos miRNAs que possam regular os genes has2, has3 e CD44 e correlacioná-los com os principais fatores prognósticos do CaP e com a recidiva bioquímica pós-prostatectomia radical. Materiais e métodos: Analisamos retrospectivamente os espécimes cirúrgicos de 53 pacientes submetidos a prostatectomia radical (PR) entre outubro de 1998 e abril 2006. A expressão dos genes e de seus miRNAs reguladores foram analisadas através da reação em cadeia da polimerase quantitativa em tempo real (qRT-PCR). O grupo controle foi constituído pelos espécimes cirúrgicos de 6 pacientes com hiperplasia prostática benigna (HPB). Correlacionamos o perfil de expressão dos 3 genes e 9 MiRNAs com o escore de Gleason, graduação ISUP, estadiamento patológico, nível de PSA pré-operatório e recidiva bioquímica definida por níveis de PSA acima de 0,2ng/mL. Resultados: Encontramos superexpressão dos genes has2 e has3 e subexpressão do CD44s no CaP localizado em comparação a HPB. Observamos subexpressão da maioria dos miRNAs no CaP com exceção do miR-511 que se encontrou superexpresso. Os miR-10a e 708 apresentaram expressão heterogênea. Adicionalmente demonstramos que menor expressão dos miR-200c e 33a está correlacionada com PSA >= 10 ng/mL, p=0,024 e p=0,002 respectivamente. A menor expressão de miR 200c também apresentou correlação com o score de Gleason >= 7 (p=0,026) e com recidiva bioquímcia (p=0,041). Conclusão: Os genes has2, has3 estão superexpressos, e o CD44s subexpresso no CaP localizado. A maioria dos miRNAs, reguladores destes genes estão subexpressos. A menor expressão dos miR-200c e 33a que regulam os genes has2 e has3 estão correlacionados com características anátomo-patológicas de pior prognóstico e com maiores taxas de recidiva bioquímica / Introduction: Prostate cancer (PCa) is the most common solid tumor and the second cause of cancer death in men in Western countries. It characteristically has heterogeneous behavior and the prognostic factors fail in predicting its aggressiveness. Thus, there is a need to search for new molecular markers to improve prognostic definition. In a previous study we showed that the loss of the standard CD44 (CD44s) adhesion molecule expression and overexpression of CD44 variants (CD44v) are characteristic of PCa. CD44 is the main binder of hyaluronic acid (HA), which is a major component of the extracellular matrix that is synthesized by the genes has2 and has3. We believe that micro RNAs (miRNA) regulate the expression of these genes in PCa. Objective: Our objective was to analyze the miRNA expression profile that probably regulate gene has2, has3 and CD44 and correlate the results with the main prognostic factors for PCa and biochemical recurrence after radical prostatectomy (RP). Materials and Methods: We retrospectively analyzed the surgical specimens of 53 patients who underwent RP between October 1998 and April 2006. The expression of genes and their regulatory miRNAs were analyzed by quantitative, real time polymerase chain reaction (qRT-PCR). The control group was represented by surgical specimens of 6 patients with benign prostatic hyperplasia (BPH). We correlate the expression profile of 3 genes and 9 miRNAs with Gleason score, ISUP graduation, pathological staging, preoperative PSA and biochemical recurrence defined by PSA levels above 0,2ng /ml. Results: We found overexpression of genes has2 and has3 and under expression of CD44s in PCa compared to HPB. We observed an under expression of most miRNAs in PCa with the exception of miR-511 that was found overexpressed. The miR-10a and 708 showed heterogeneous expressionprofile. Additionally we demonstrated that lower expression of miR-200c and 33a was correlated with PSA >= 10 ng/mL, p=0.024 and p = 0.002 respectively. The lower expression of miR 200c was also correlated with Gleason score >= 7 (p=0.026) and biochemical recurrence (p=0.041). Conclusion: The has2 and has3 were overexpressed while the CD44s was underexpressed in localized PCa. Most of miRNAs that regulate these genes were underexpressed. The expression of miR-200c and 33a, regulators of has2 and has3 genes, were correlated with unfavorable characteristics of PCa and with biochemical recurrence
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Optimization of Acidic Degradation of Hyaluronic Acid using Design of ExperimentsSandqvist Wedin, Emma January 2019 (has links)
Hyaluronic acid (HA) is an unbranched polysaccharide consisting of the repeating disaccharide unit β(1→4)-GlcA-β(1→3)-GlcNAc and is a naturally occurring biopolymer in bacteria and vertebras. HA is predominantly found in the extracellular matrix (ECM) and the in vivo function of HA can vary depending on molecular weight (Mw) for instance high Mw HA is reported to be anti-angiogenic while low Mw HA induces angiogenesis. HA is a popular component for hydrogels such as dermal fillers. HA is commonly used in dermal fillers. However, other materials, such as other polymers, can be used as well. The project goal was to investigate different degradation processes for production of target Mw HA. Alkaline and acidic degradation processes in combination with increased temperatures seemed as the most promising methods. Degradation tests performed both in aqueous solution as well as heterogeneously in ethanol were evaluated. The acidic degradation in aqueous solution was proven to have the largest degradation constant. Both a robustness test as well as a Design of Experiments (DoE) was performed to investigate the influence different factors had on the degradation speed. The investigated factors were HA concentration, HCl concentration and temperature. Temperature and HCl concentrations proved to be the most influencing factors and a model was developed in the DoE software MODDE to describe how the factors influenced the degradation constant. The model was established as a good significant model with a Q2 value of 0.998 and relative standard deviation (RSD) value of 0.022 after a logarithmic transformation was performed as well as a simplification of the model by excluding some of the factor interactions. The acidic degradation method also proved to be a highly robust method which easily could be used to produce target Mw HA.
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Uso de dexametasona tópica isolada e associada ao ácido hialurônico na preservação auditiva de pacientes submetidos à cirurgia de implante coclear / Hearing preservation using topical dexamethasone isolated and associated with hyaluronic acid in cochlear implantationRamos, Bernardo Faria 26 September 2013 (has links)
INTRODUÇÃO: A introdução dos princípios da soft surgery desencadeou busca constante pela preservação auditiva, principalmente após a expansão dos critérios de inclusão para a cirurgia do implante coclear. Esses princípios cirúrgicos, associados a novos modelos de eletrodos e ao uso de fármacos no intraoperatório, têm sido utilizados a partir do melhor conhecimento da anatomia da orelha interna e da repercussão dos mecanismos inflamatórios desencadeados pelo trauma de inserção dos eletrodos. O objetivo deste estudo é avaliar o efeito de dexametasona tópica isolada e associada ao ácido hialurônico no intraoperatório de pacientes com audição residual submetidos ao implante coclear na preservação dos limiares tonais dos mesmos. MÉTODO: Foram avaliados 18 pacientes adultos com surdez severaprofunda submetidos à cirurgia de implante coclear divididos em 3 grupos: Implante coclear como grupo-controle, grupo 1; implante coclear com uso de dexametasona tópica no intraoperatório, grupo 2; e implante coclear com uso de dexametasona tópica associada ao ácido hialurônico no intraoperatório, grupo 3. Foram comparadas as médias dos limiares tonais nas frequências de 125, 250 e 500 Hz e nas frequências de 1000, 2000 e 4000 Hz no pré-operatório e no pós-operatório. RESULTADOS: A diferença entre as médias dos limiares tonais nas frequências baixas obtidas no 6º mês de pós-operatório e no pré-operatório foi de 28,03 dB + 6,77 dB no grupo 1, 30 dB + 14,53 dB no grupo 2 e 7,23 dB + 6,12 dB no grupo 3. Houve diferença estatisticamente significante dos valores do grupo 3 em relação ao grupo 1 e 2 (p = 0,002). A diferença entre as médias dos limiares tonais nas frequências altas obtidas no 6º mês de pós-operatório e no pré-operatório foi de 11,12 dB (DP + 9,71 dB) no grupo 1, 22,77 dB (DP + 12,79 dB) e 3,89 dB (DP + 3,1 dB). Houve diferença estatística entre os grupos 2 e 3 (p = 0,01). CONCLUSÕES: A associação do uso tópico de dexametasona e ácido hialurônico no intraoperatório de pacientes submetidos à cirurgia do implante coclear foi significantemente superior ao grupo controle e ao grupo no qual foi utilizado apenas a dexametasona tópica na preservação dos limiares auditivos. Por outro lado, o uso isolado de dexametasona tópica não demonstrou resultados superiores na preservação dos limiares acústicos quando comparado ao grupo controle / INTRODUCTION: The expansion of candidacy criteria for cochlear implantation led to a constant care for hearing preservation. The in-depth knowledge of the anatomy and function of the inner ear as well as the inflammatory repercussion caused by the insertion trauma led to the development of soft surgery principles, new electrode designs and pharmacotherapy. The purpose of this study was to compare the effects of topical dexamethasone isolated and associated with hyaluronic acid in hearing preservation in cochlear implantation. METHOD: Eighteen severely to profoundly hearing impaired adult patients were evaluated and divided into 3 groups: Cochlear implantation as a control group in group 1, cochlear implantation using topical dexamethasone intraoperatively in group 2 and cochlear implantation using topical dexamethasone associated with hyaluronic acid intraoperatively in group 3. Preimplant and postimplant low frequency and high frequency pure-tone average (PTA) from 125, 250, 500 Hz and 1000, 2000, 4000 Hz were calculated and compared from unaided audiograms. RESULTS: The mean changes in the low frequency PTA of preoperative and postoperative thresholds were 28.03 dB + 6.77 dB in group 1, 30 dB + 14.53 dB in group 2 and 7.23 dB + 6.12 dB in group 3. There was statistical difference comparing group 3 with group 1 and 2 (p = 0.002). The mean changes in the high frequency PTA of preoperative and postoperative thresholds were 11.12 dB + 9.71 dB in group 1, 22.77 dB + 12.79 dB e 3.89 dB + 3.1 dB. There was statistical difference between group 2 and 3 (p = 0.01). CONCLUSIONS: The use of topical dexamethasone associated with hyaluronic acid intraoperatively in cochlear implant surgery demonstrated a statistically significant difference in the preservation of low frequency thresholds when compared with the use of isolated topical dexamethasone and a control group. The use of isolated topical dexamethasone was not superior in hearing preservation when compared to a control group
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Gel permeation chromatography in semi-preparative scale apply to the characterization, purification and fractionation of microbial hyaluronic acid / Cromatografia de permeaÃÃo em gel em escala semi-preservativa aplicada à caracterizaÃÃo, purificaÃÃo e fracionamento do Ãcido hialurÃnico produzido por cultivo de microorganismosAnayla dos Santos Sousa 20 March 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Hyaluronic acid (HA) is a linear, unbranched polymer, composed by simple disaccharide units, whose molar mass may range in a wide interval of distribution (104-107 Da). It is used in pharmaceutical and cosmetic applications depending on its average molecular mass. The fractionation of macromolecules of the order of magnitude of the HA may be performed by gel permeation or size-exclusion chromatography (GPC). The objective of this work is to study the characterization, purification and fractionation of microbial HA by using GPC. HA was supplied by the Department of Biotechnological Processes (DPB/FEQ/UNICAMP), having been produced by microorganisms â Streptococcus zooepidemicus â in synthetic culture media. After being centrifuged from the fermentation broth, HA was precipitated with ethanol and then dissolved in saline solution, this pre-purification procedure being performed up to four times. The presence of proteic contaminants was identified by electrophoresis in polyacrylamide gel under denaturant conditions (SDS-PAGE) and quantified by the Bradford method. For the HA sample which had been precipitated in ethanol and dissolved in 0.1 M NaNO3 four times, protein concentration was found to be nearly 100 μg/mL. The sodium salt of commercial (Sigma Aldrich - EUA) microbial HA was used as standard in order to measure a calibration curve to assess HA concentration in the samples. For the sample precipitated in ethanol and dissolved in 0.1 M NaNO3 four times, AH concentration was found to be approximately 780 μg/mL. Molar mass distribution of HA samples was assessed by GPC, both in analytical and semi-preparative scale, using refractive index (RI) and UV/Vis (280 nm) detectors, 0.1 M NaNO3 as mobile phase, flow rate 0.8 mL/min and tracers dextran and pullulan (polymers of similar hydrodynamic volume as compared to HA) as molar mass standards. The samples showed molar mass distributions in the range of 103 to 107 Da, after being precipitated and dissolved four times. For these samples, the average molar mass was found to be in the order of magnitude of 105 Da. In the semi-preparative column Superose, it was possible to separate HA fractions, with molar mass above 105 Da, and free of proteic contaminants, in an elution interval of 10 minutes / O Ãcido HialurÃnico (AH) à um polÃmero linear, nÃo ramificado, composto por unidades dissacarÃdicas simples, cuja massa molar pode se distribuir num largo intervalo (104-107 Da). à usado em aplicaÃÃes farmacÃuticas e cosmÃticas dependendo de sua massa molar mÃdia. A separaÃÃo de macromolÃculas da ordem de grandeza do AH à possÃvel atravÃs da Cromatografia de permeaÃÃo em gel (GPC). Este trabalho tem como objetivo estudar a caracterizaÃÃo, purificaÃÃo e fracionamento do AH produzido por microorganismos, utilizando GPC. O AH, cedido pelo Departamento de Processos BiotecnolÃgicos (DPB/FEQ/UNICAMP), foi obtido por cultivo de microorganismos - Streptococcus zooepidemicus - em meio de cultura sintÃtico. ApÃs centrifugaÃÃo do caldo de fermentaÃÃo, o AH foi precipitado com etanol e ressuspenso em soluÃÃo salina, sendo esta etapa de prÃ-purificaÃÃo executada atà quatro vezes. A presenÃa de contaminantes protÃicos foi identificada por eletroforese em gel de poliacrilamida sob condiÃÃes desnaturantes (SDS-PAGE) e quantificada pelo mÃtodo de Bradford, obtendo-se 97,20 μg/mL, para a amostra de AH apÃs quatro precipitaÃÃes em etanol e ressuspensÃes em NaNO3 0,1 M. Para as determinaÃÃes de concentraÃÃo de AH nas amostras estudadas, utilizou-se o sal sÃdico de AH microbial comercial (Sigma Aldrich - EUA) como padrÃo. Quantificando-se a amostra de AH apÃs quatro precipitaÃÃes em etanol e ressuspensÃes em NaNO3 0,1 M, obteve-se 783,70 μg/mL. A distribuiÃÃo da massa molar do AH foi avaliada por GPC, em escala analÃtica, utilizando coluna Shodex OHPak-SB806M-HQ e, em escala semi-preparativa, a coluna Superose 6, detectores de Ãndice de refraÃÃo e UV/Vis (280 nm), NaNO3 0,1 M como fase mÃvel, vazÃo de 0,8 mL/min e padrÃes de Dextrana e Pullulan (polÃmeros de volume hidrodinÃmico semelhante ao AH) como marcadores de massa molar (5,2x103 - 7,9x106 Da e 5,8x103 â 8,53x105 Da, respectivamente). A amostra apresentou uma distribuiÃÃo polimÃrica na faixa de 103 a 107 Da, apÃs quatro precipitaÃÃes em etanol e ressuspensÃes em NaNO3 0,1 M, sendo sua massa molar mÃdia da ordem de 105 Da. Foi possÃvel separar fraÃÃes de AH, acima de 105 Da, livre de contaminantes protÃicos, num intervalo de aproximadamente 10 minutos, na coluna Superose 6
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Subgingivale parodontopathogene Bakterien und Bezug zur Klinik bei Anwendung von Gengigel® beim scaling and root planing / Subgingival periodontopathic bacteria and relation to the clinic with the use of Gengigel ® for scaling and root planingRenatus, Antonio 04 June 2012 (has links) (PDF)
Ziel dieser Studie war es, Auswirkungen von subgingival applizierter Hyaluronsäure (Gengigel®) nach scaling and root planing (SRP) auf mikrobiologische Variablen bei Parodontitispatienten nachzuweisen. Dabei wurden die möglichen Zusammenhänge zwischen Ergebnissen der Bakterienspezies und zuvor ermittelten Ergebnissen klinischer Variablen untersucht. An der Untersuchung nahmen 20 Männer und 29 Frauen teil. Es erfolgte eine Randomisierung in zwei Gruppen, bestehend aus einer Testgruppe mit 23 und einer Kontrollgruppe mit 26 Probanden. Bei den Versuchteilnehmern wurde in zwei Sitzungen in einem 24-stündigen Abstand ein SRP mittels Hand- und Ultraschallinstrumenten durchgeführt. Am Ende des SRP wurde in der Testgruppe Gengigel prof® (mit 0,8% Hyaluronsäure) in die parodontalen Taschen eingebracht. Zusätzlich trugen die Probanden der Testgruppe während der folgenden 14 Tage zweimal täglich morgens und abends Gengigel® (0,2%) auf den Gingivarand auf. In der Kontrollgruppe erfolgte das übliche SRP ohne Verwendung von Gengigel®. Alle Probanden wurden zu Beginn der Untersuchung, nach drei und sechs Monaten aus parodontologischer Sicht untersucht. Des Weiteren wurden Proben der Sulkusflüssigkeit für eine spätere Analyse von zehn parodontopathogenen Keimen sowie der Peroxidase- und Granulozytenaktivität gewonnen. Im Gegensatz zur kontinuierlichen Zunahme in der Kontrollgruppe (p=0,035) konnte beim Verlauf der Gesamtbakterienzahl für die Testgruppe keine Veränderung der Keimzahlen (p=0,737) beobachtet werden. In der Testgruppe wurde nach sechs Monaten für Campylobacter rectus, Treponema denticola und Aggregatibacter actinomycetemcomitans eine Reduktion der Keimbelastung festgestellt (p=0,05; p=0,043; p=0,066). Am Ende der Untersuchung waren in der Testgruppe keine Unterschiede in der bakteriellen Besiedlung unterschiedlich tiefer Taschen mehr nachweisbar (p=1). In der Testgruppe bestand eine stark signifikante Korrelation der Granulozytenaktivität mit der Zeit (r=0,443; p<0,0001) und mit der Gesamtbakterienzahl (r=0,336; p=0,009). Die Ergebnisse der Studie weisen auf einen wachstumshemmenden Effekt der Hyaluronsäure auf parodontopathogene Bakterien hin, welcher womöglich auf einer indirekten Interaktion mit dem Immunsystem basiert.
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Engineering zonally organized articular cartilageNguyen, Lonnissa Hong 14 October 2011 (has links)
Cartilage regeneration is one of the most widely studied areas in tissue-engineering. Despite significant progress, most efforts to date have only focused on generating homogenous tissues whose bulk properties are similar to articular cartilage. However, anatomically and functionally, articular cartilage consists of four spatially distinct regions: the superficial, transitional, deep, and calcified zones. Each zone is characterized by unique extra-cellular matrix (ECM) compositions, mechanical properties, and cellular organization. The ECM is primarily composed of type II collagen and glycosaminoglycans (GAGs), whose relative concentrations vary between zones and therefore lead to distinctive mechanical properties.
One of the major unsolved challenges in engineering cartilage has been the inability to regenerate tissue that mimics the zonal architecture of articular cartilage. Recent studies have attempted to imitate this spatial organization using zone-specific chondrocytes isolated from donor animal cartilage. Directed differentiation of a single stem population into zonally organized native-like articular cartilage has not yet been reported.
This dissertation reports that hydrogels, incorporating both synthetic and natural polymers as well as cell-induced degradability, are suitable for generating zone-specific chondrogenic phenotypes from a single MSC population. Specifically, cues provided from the unique combinations of chondroitin sulfate (CS), hyaluronic acid (HA), and MMP-sensitive peptide (MMP-pep) within a PEG-based hydrogel, direct the chondrogenic differentiation of MSCs. The findings of this dissertation demonstrate the capability of creating native-like and mechanically relevant articular cartilage consisting of zone specific layers. This ability provides a new direction in cartilage tissue engineering and could be invaluable for cartilage repair if incorporated with current minimally invasive surgical techniques. / text
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Temporal and Spatial Characterization of Uterine and Oviductal Environment in the PigPasternak, Jonathan A. Unknown Date
No description available.
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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 /El Abras Ankha, Milagros del Valle. January 2018 (has links)
Orientador: Yasmin Rodarte Carvalho / Banca: Rubens Guimarães Filho / Banca: Carla Roberta Tim / Banca: Luana Marotta Reis de Vasconcellos / Banca: Mônica Ghislaine Oliveira Alves / Resumo: 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 ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract : 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 ......(Resumo completo, clicar acesso eletrônico abaixo) / Doutor
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Desenvolvimento de nanoemuls?es contendo ?cido retinoico funcionalizadas com ?cido hialur?nico como alternativa para o tratamento de c?ncerTinoco, Let?cia M?rcia da Silva January 2016 (has links)
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Previous issue date: 2016 / O ?cido retinoico (AR), um derivado da vitamina A, ? um dos exemplos mais bem-sucedidos de f?rmacos usados na terapia de diferencia??o do c?ncer. O AR ? um f?rmaco altamente lipof?lico (log P 4,6) que apresenta baixa solubilidade aquosa, limitando sua utiliza??o parenteral. Dessa forma, sua incorpora??o em nanocarreadores lip?dicos tem sido proposta como uma alternativa promissora para a administra??o desse f?rmaco. O maior direcionamento dos nanossistemas para as c?lulas tumorais pode ser obtido por meio de modifica??es na superf?cie deste, como o revestimento com ?cido hialur?nico (AH), que se liga a receptor CD44 sobre-expresso em alguns tumores. Assim sendo, este trabalho teve por objetivo principal desenvolver, caracterizar e avaliar a atividade antineopl?sica in vitro de nanoemuls?es contendo AR revestidas e n?o revestidas com AH para tratamento de c?ncer de mama. Primeiramente, foi desenvolvido um m?todo espectrofotom?trico, com detec??o do AR em 324 nm, que foi validado em rela??o ? seletividade em rela??o aos componentes de matriz e aos produtos de degrada??o for?ada, linearidade, precis?o, exatid?o e robustez, conforme a legisla??o pertinente. Em seguida, foram desenvolvidas e caracterizadas nanoemuls?es (NE) preparadas por emulsifica??o espont?nea e revestidas eletrostaticamente com AH em diferentes concentra??es. Ap?s o revestimento com 0,5 mg/mL de AH, a NE escolhida apresentou tamanho de 158 ? 5 nm, distribui??o monodispersa e potencial zeta de -19,7 ? 1,20 mV e um teor de encapsula??o de 99,2 ? 0,5%, estando compat?vel com a administra??o parenteral. Al?m disso, as formula??es revestidas permaneceram est?veis ao longo de 60 dias armazenadas a 4?C. O perfil de libera??o do AR a partir dos nanossistemas foi avaliado e observou-se que segue uma cin?tica de primeira ordem, de forma que a taxa de libera??o depende da concentra??o do f?rmaco ainda presente na matriz. Foram, por fim, avaliados os efeitos citot?xicos em linhagens de c?lulas de c?ncer de mama (MCF-7 e MDA-MB-231) e fibroblastos normais (L929) e observou-se que a formula??o revestida promove aumento de atividade antic?ncer do AR, especialmente nas c?lulas que expressam mais os receptores CD44 (MDA-MB-231) e reduzida toxicidade em rela??o ?s c?lulas normais. Desta forma, a encapsula??o do AR em NE revestida por AH pode ser uma abordagem interessante para aumentar a efic?cia e a biodisponibilidade do AR no tratamento do c?ncer de mama e outros tipos de c?ncer que sobre-expressam esse receptor. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Ci?ncias Farmac?uticas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Retinoids, such as all-trans retinoic acid (RA), are structural molecules derived from vitamin A and play important roles in various cell types, especially on vision, cell proliferation and differentiation. RA is a lipophilic acid (log P 4.6) with low aqueous solubility, which limits its pharmaceutical use. In order to allow its parenteral administration, an interesting alternative could be its incorporation in lipid nanocarrier systems, such as nanoemulsions (NE). On the other hand, it is possible to increase the target to CD44 receptor expressing tumor cells, coating the NE surface with hyaluronic acid (HA). Therefore, the main goal of this study was to develop, characterize and evaluate the in vitro antitumor activity of RA-loaded NE coated with HA for the treatment of breast cancer. First, a spectrophotometric method was developed, with RA detection at 324 nm, which was validated with regard to selectivity to matrix components and forced degradation products, linearity, precision, accuracy and robustness, in accordance with the proper legislation. Then, the NE, prepared by the spontaneous emulsification and electrostatically coated with HA in different concentrations, were developed and characterized. After coating with 0.5 mg/mL, the chosen HA-coated NE presented size of 158 ? 5 nm, monodisperse distribution, zeta potential of -19.7 ? 1.20 mV and encapsulating efficiency of 99.2 ? 0.5%, which is compatible with parenteral administration. Moreover, the coated formulations remained stable over 60 days stored at 4 ?C. The RA release profile from the nanosystems was evaluated and it follows the first order kinetics, so that the release rate depends on the drug concentration still present in the matrix. Finally, the cytotoxic effects were assessed in breast cancer cell lines (MCF-7 and MDA-MB-231) and in normal fibroblasts (L929), and found that the coated formulation promotes increased anticancer activity of RA, especially in cells expressing plus CD44 receptors (MDA-MB-231) and reduced toxicity compared to normal cells. Thus, the encapsulation of RA in HA-coated NE can be an interesting approach to increase the RA efficacy and bioavailability in the treatment of breast cancer and other cancers overexpressing that receptor.
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Avaliação da segurança e estudo da permeação e retenção cutânea de géis de ácido hialurônicoMartini, Paula Cressoni [UNESP] 21 February 2011 (has links) (PDF)
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martini_pc_me_arafcf.pdf: 595100 bytes, checksum: bcb255af52349311710acfecbb49c0e8 (MD5) / Universidade Estadual Paulista (UNESP) / O aumento da expectativa de vida tem provocado grande demanda por produtos que auxiliem na prevenção do envelhecimento da pele. O ácido hialurônico (AH) está sendo muito utilizado em formulações antienvelhecimento por se acreditar que ele possa atenuar os efeitos que o tempo produz na pele. Porém, para o desenvolvimento de um cosmético, é necessário avaliar o risco potencial dos ingredientes que compõem a formulação, que devem estar em concentração que apresente margem de segurança adequada, sendo importante a realização de teste de absorção, estudo do potencial de risco irritativo e testes de mutagenicidade. O objetivo deste estudo foi desenvolver um gel de ácido hialurônico com alta massa molecular e incorporar ácido hialurônico de massas moleculares menores, realizar o controle microbiológico dos géis, avaliar a toxicidade dérmica aguda e a citotoxicidade, determinar o comportamento reológico das formulações, analisar seu perfil de liberação, permeação e retenção cutânea in vitro. Foi preparado como gel base, a mistura de água e AH de alta massa molecular e, posteriormente, neste gel formado foram incorporados os AHs de menores massas moleculares. O controle de qualidade microbiológico foi realizado de acordo com a Farmacopeia Brasileira (2010), a avaliação da toxicidade dérmica aguda foi realizada utilizando-se 25 ratos wistar, que foram divididos em 5 grupos com 5 animais em que cada grupo recebeu a aplicação de um dos géis para posterior analise dos resultados. Para a avaliação da citotoxicidade utilizou-se o método colorimétrico 3-(4,5-dimetiltiazol-2-il)2,5-difenil brometo de tetrazoilium (MTT) descrito por MOSMANN, utilizando-se linhagens celulares de HepG2 (Human Epidermoide Cancer Cells) e HaCaT. As amostras tiveram seu comportamento reológico avaliado em reômetro HAAKE. O estudo de liberação, permeação e retenção cutânea... / Increased life expectancy has caused a great demand for products that help in the prevention of skin aging. Hyaluronic acid is being used in anti-aging formulations because it is expected that it can decrease the effects of time in the skin. However, for the development of a cosmetic it is necessary to evaluate the potential risk of the ingredients in the formulation that should be with adequate concentration to provide a margin of safety, being important to carry out absorption test, studies of the potential risk of irritating the skin and mutagenicity tests. The aim of this study was to develop a gel of hyaluronic acid with high molecular weight and incorporate hyaluronic acid with small molecular weights in it, analyze the microbiological control of the gels, evaluate the acute dermal toxicity and cytotoxicity, determine rheological characteristics, analyze the release profile, skin permeation and retention in vitro. It was prepared like gel base, the mixture of water and AH of high molecular weight, and after was incorporate AH of smaller molecular weight. The quality control microbiological was accomplished in agreement with Brazilian Pharmacopoeia (2010), the evaluate the acute dermal toxicity was made with 25 rat wistar, that were divided in 5 groups with 5 animals in each group received the application from one of the gels for subsequent analyzes of the results. For the evaluation of the cytotoxicity was used the method colorimeter 3-(4,5-dimetiltiazol-2-il)2,5-difenil tetrazoilium bromide (MTT) described by MOSMANN (1983), being used cellular lineages of HepG2 (Human Epidermoide Câncer Cells) and HaCaT. The samples had its behavior rheological characteristics. The analyze the release profile, skin permeation and retention were accomplished using cells of Franz modified. The microbiological was in agreement... (Complete abstract click electronic access below)
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