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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.
11

Compara??o do efeito do plasma rico em plaquetas e fibrina rica em plaquetas no reparo do tend?o de Aquiles em ratos

Dietrich, Franciele 28 March 2012 (has links)
Made available in DSpace on 2015-04-14T13:35:30Z (GMT). No. of bitstreams: 1 438171.pdf: 6920524 bytes, checksum: f5e5c6d7e177dfd60f3b3303552cc797 (MD5) Previous issue date: 2012-03-28 / OBJECTIVE : To evaluate and compare the effect of using Platelet-Rich Plasma (PRP) and Platelet-Rich Fibrin (PRF) in the repair of the Achilles tendon (TA) of rats. MATERIAL and METHODS : Forty-eight adult male rats randomized into three experimental groups: PRP, PRF and Control (saline 0.9%). A 3 cm longitudinal incision was made in the right leg of each rat in order to expose the TA. Later, it was a break in the same horizontal, and the repair performed with suture Kessler-type, when the sequence was applied 50 &#956;L of the treatment in question. After 14 and 28 days postoperatively, the targeted part of the TA was removed, thus initializing the histological processing (Hematoxylin/Eosin; Sirius Red) to obtain results. The data obtained were expressed at 5% significance level (p <0.05) with mean ? SE. RESULTS : When comparing the three groups together, as to time and area of collagen type I and III, only statistical difference between the control group (16.22%) and the PRP group (37.16%) at 14 days after the treatment, no statistically significant difference was observed in the other groups. In the same way, when compared within groups of 14 and 28 days, the PRF group showed a significant difference for collagen I (27.76% and 47.74%) and III (66.94% and 46%) respectively. Control group showed significant difference in collagen type I (14.20% and 40.90%), not observed any significant difference in the PRP group. When evaluated on Hematoxylin/Eosin staining, PRP and control were similar in the times studied, differing only in the presence of hemorrhage, that was more expressed in the PRP group. Already the group PRF has shown to be more organized, especially in time of 28 days compared to the other two treatments. CONCLUSION : The data from this study suggest that the Platelet-Rich Fibrin tends to promote the accelerated regeneration of the Achilles tendon of rats, bringing promising prospects for future use in the clinic. / OBJETIVO : Avaliar e comparar o efeito do uso de plasma rico em plaquetas (PRP) e fibrina rica em plaquetas (PRF) no reparo do tend?o de Aquiles (TA) de ratos. MATERIAL e M?TODOS : Foram utilizados 48 ratos machos adultos distribu?dos randomicamente em tr?s grupos experimentais: PRP, PRF e Controle (solu??o salina 0,9%). Uma incis?o longitudinal de 3 cm foi realizada na perna direita de cada rato, a fim de expor o TA. Posteriormente, fez-se uma ruptura horizontal no mesmo, sendo a repara??o realizada com sutura do tipo Kessler, onde na seq??ncia foi aplicado 50 &#956;L do tratamento em quest?o. Passados 14 e 28 dias p?s- operat?rio, a parte segmentada do TA foi removida, inicializando assim o processo histol?gico (Hematoxilina/Eosina; Picros?rius Red) para obten??o de resultados. Os dados obtidos foram expressos ao n?vel de 5% de signific?ncia (p < 0.05) com m?dia ? EP. RESULTADOS : Ao comparar os tr?s grupos entre si, quanto ao tempo e ?rea de col?geno tipo I e III, houve diferen?a estat?stica somente entre o grupo Controle (16.22%) e o grupo PRP (37.16%) aos 14 dias ap?s o tratamento, n?o sendo observada diferen?a estatisticamente significativa nos outros grupos. Da mesma forma, quando comparados intra-grupos em 14 e 28 dias, o grupo PRF apresentou diferen?a significativa para col?geno I (27.76% e 47.74%) e III (66.94% e 46%) respectivamente. Grupo Controle demonstrou diferen?a significativa para col?geno tipo I (14.20% e 40.90%), n?o sendo observada qualquer diferen?a significativa no grupo PRP. Quando avaliados na colora??o Hematoxilina e Eosina, PRP e Controle apresentaram-se semelhantes nos tempos avaliados, diferindo apenas quanto a presen?a de hemorragia, que foi mais expressa no grupo PRP. J? o grupo PRF demonstrou-se mais organizado, principalmente no tempo de 28 dias quando comparado aos outros dois tratamentos. CONCLUS?O : Os dados obtidos neste trabalho sugerem que a Fibrina Rica em Plaquetas tem tend?ncia a promover a regenera??o acelerada do tend?o de Aquiles de ratos, trazendo perspectivas promissoras para futuras utiliza??es na cl?nica.
12

Efeito do plasma rico em plaquetas e da fibrina rica em plaquetas na cicatriza??o de feridas cut?neas em ratos

Camargo, Fernanda Ferreira de 08 August 2013 (has links)
Made available in DSpace on 2015-04-14T13:35:49Z (GMT). No. of bitstreams: 1 452038.pdf: 5926182 bytes, checksum: 5375eb92e47f0a2a30ef9fa65dc549c5 (MD5) Previous issue date: 2013-08-08 / Objective: To evaluate the effect of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) on cutaneous wound healing in rats by comparing treated and control wounds. Material and Methods: Forty-eight Wistar rats were used in the study. Two wounds with 1-cm diameter, of total skin thickness, were excised from the back of the animals and treated with either PRP or PRF and saline (paired model). The wounds were evaluated immediately after the procedure and after 7 and 14 days using macroscopic (photographs) and microscopic (histology) methods. The photographs were used to measure the area of wounds in order to analyse wound contraction (morphometric analysis). The histological images permitted a count-analysis of collagen concentration (histomorphometric analysis) while the histological slides providet the description of the wounds characteristics. Results: Morphometric analysis revealed statistically significant time effect (P<0.001) and treatment group effect (P=0.022) over the observation period. The rate of wound contraction was higher in PRF-treated wounds than in PRP-treated wounds (P=0.030). In the histomorphometric analysis, mean collagen concentration, on the images of the experimental groups, increased significantly (P<0.001) from day 7 to day 14. There was wide variation in the percentage of collagen concentration: 129% in the PRF group vs. 22% in the PRP group; however, this difference did not achieve statistical significance (P=0.380). Histology of the wounds suggested a more accelerated healing process in the PRF group vs. the PRP group, despite the lack of statistical significance in the characteristics analyzed. PRP-treated and PRF-treated groups were not statistically superior to their controls in any of the studied variables. Conclusion: The present results suggest that treatment with PRP and PRF were not more effective than saline for cutaneous wound healing in rats. However, PRF proved to be superior to PRP. / Objetivo: Avaliar o efeito do Plasma Rico em Plaquetas (PRP) e da Fibrina Rica em Plaquetas (PRF) na cicatriza??o de feridas cut?neas em ratos, comparando os tratamentos entre si e com seus respectivos grupos controle. Material e M?todos: Foram utilizados 48 ratos Wistar. Duas feridas de 1,0 cm de di?metro, de espessura total da pele, foram excisadas do dorso dos animais e tratadas com PRP ou PRF e soro fisiol?gico (modelo emparelhado). As feridas foram avaliadas no p?s-operat?rio imediato e depois de 7 e 14 dias, de forma macrosc?pica (fotografias) e microsc?pica (histologia). As fotografias forneceram medidas da ?rea das feridas, possibilitando analisar sua contra??o (an?lise morfom?trica). As imagens histol?gicas permitiram calcular a concentra??o de col?geno nas feridas (an?lise histomorfom?trica) e as l?minas histol?gicas a descrever suas caracter?sticas. Resultados: Quanto ? an?lise morfom?trica, o efeito do tempo (P<0,001) e dos grupos (P=0,022), ao longo do per?odo de observa??o, foi estatisticamente significativo. A taxa de contra??o das feridas tratadas com PRF foi maior do que as tratadas com PRP (P=0,030). Na an?lise histomorfom?trica, a m?dia da concentra??o de col?geno, nas imagens dos grupos experimentais, apresentou um aumento do 7? para o 14? dia, considerado significativo (P<0,001). Houve grande varia??o percentual na concentra??o de col?geno: 129% para a PRF contra 22% para o PRP, por?m, sem signific?ncia estat?stica (P=0,380). A descri??o histol?gica das feridas sugeriu que o grupo PRF apresentou maior acelera??o do reparo quando comparado ao grupo PRP, apesar da aus?ncia de signific?ncia estat?stica nas caracter?sticas avaliadas. Os grupos de tratamento PRP e PRF n?o foram estatisticamente superiores aos seus grupos controle nas vari?veis estudadas. Conclus?o: Os dados do presente estudo sugerem que o PRP e a PRF n?o apresentaram resultados mais eficazes do que o soro fisiol?gico na cicatriza??o de feridas cut?neas em ratos. No entanto, a PRF mostrou-se superior ao PRP.
13

Estudo prospectivo cl?nico-radiogr?fico de implantes curtos unit?rios na regi?o posterior

Villarinho, Eduardo Aydos 06 May 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-08-24T17:18:27Z No. of bitstreams: 1 TES_EDUARDO_AYDOS_VILLARINHO_COMPLETO.pdf: 1401374 bytes, checksum: 7bb19e0c340fb5e5a2378e17d5752239 (MD5) / Made available in DSpace on 2016-08-24T17:18:27Z (GMT). No. of bitstreams: 1 TES_EDUARDO_AYDOS_VILLARINHO_COMPLETO.pdf: 1401374 bytes, checksum: 7bb19e0c340fb5e5a2378e17d5752239 (MD5) Previous issue date: 2016-05-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Short dental implants offer to dentists and patients a feasible option for prosthetic rehabilitation in cases with anatomic limitations when compared with regenerative techniques. This prospective, clinical-radiographic, cohort study aimed: in manuscript 1, to evaluate the rates of prosthetics failures, implants failures and marginal bone loss of 6-mm dental implants restored with single crowns in posterior region, and their risk factors; and 2) in manuscript 2, to present the development of a new method to measure volumetric alterations of bone level around dental implants using superimposition of 3D images. Methodology: A total of 46 implants Standard Plus Regular Neck SLActive? (Straumann), 6-mm length and 4.1-mm diameter, were installed in 20 patients. Clinical and radiographic data were collected after implant surgery, after prosthesis installation and every 12-month follow-up. Cone beam computed tomographic (CBCT) images were taken after implant surgery, and 12 and 24 months after prosthesis installation. In manuscript 1, the potential risk factors (arch, presence of bruxism, maximum bite force, clinical and anatomical crown/implant (C/I) ratios, occlusal table) were analyzed for the outcomes: implant survival, bone loss (linear) and prosthetic failures. In manuscript 2, the tridimensional images of bone perimeter closest to the implant were built using the software Mimics?, converted into the STL format, and then exported to the software Geomagic Studio?, where they were 3D-superimposed and volumetrically assessed. Results: In manuscript 1, the average time of clinical follow-up was 45 ? 9 (16; 57) months. There was no early implant loss; after prosthetic loading four implants failed (survival of 91.3%) and 13 prosthetic failures occurred (28.3%), resulting in a 65.2% success rate. The frailty model for survival analysis showed a probability of 95% implant failure in the mandible in relation to the maxilla. The average bone loss was 0.2 ? 0.4mm in the first year, 0.1 ? 0.2mm in the second year, 0.1 ? 0.3mm in the third year, and 0.2 ? 0.4mm in the fourth year, with average cumulative bone loss of 0.3 ? 0.5mm at 48 months. In the multilevel model the effects of clinical C/I ratio (P<0.001) and time (P<0.001) were significant for bone loss, estimating that an average 0.1 bone loss is associated with each increase of one unit of time (12 months) and of 0.1 of clinical C/I ratio. No other potential risk factors showed significant relation with the outcomes. In manuscript 2, the average volumetric bone loss was 7.2 ? 6.1 mm3 in the first year, 6.4 ? 7.8 mm3 in the second year, and 12.6 ? 8.0 mm3 for the cumulative period of 2 years in function. Conclusions: Within the conditions of this study, the 6-mm implants proved to be a safe alternative for oral rehabilitation. However, the mandible had higher risk of failure than the maxilla. The prosthetic complications ratio was higher than the ones reported in the literature, but all of them were repaired easily. Time and clinical C/I ratio were predictors for bone loss. However, the amount of bone loss was within the success criteria adopted. The measurement of volumetric bone alterations around implants is possible, since the CBCT images have good contrast and sharpness, particularly for the implant contour. Improvement in the quality of the images and software filters for detection of bone tissue would be important to turn this method faster and clinically useful. / O uso de implantes curtos oferece aos dentistas e aos pacientes uma op??o de f?cil abordagem para restaura??es prot?ticas frente ?s limita??es anat?micas quando comparadas ?s t?cnicas regenerativas. O presente estudo cl?nico-radiogr?fico prospectivo de coorte objetivou atrav?s do manuscrito 1 avaliar a taxa de complica??es prot?ticas, falhas do implante e perda ?ssea marginal dos implantes dent?rios de 6-mm restaurados com coroas unit?rias em regi?es posteriores, e seus poss?veis fatores de risco, bem como atrav?s do manuscrito 2 apresentar o desenvolvimento de um novo m?todo para aferi??o de altera??es volum?tricas do n?vel ?sseo ao redor dos implantes dent?rios utilizando sobreposi??o de imagens tridimensionais. Metodologia: Foram instalados 46 implantes Standard Plus Regular Neck SLActive? (Straumann) de 6-mm de comprimento e 4.1-mm de di?metro em 20 pacientes. Os pacientes foram examinados cl?nico-radiograficamente logo ap?s a instala??o do implante, da pr?tese e posteriormente a cada 12 meses. Sendo realizada tomografia computadorizada Cone Beam (CBCT) logo ap?s a instala??o do implante, 12 e 24 meses ap?s a pr?tese. No manuscrito 1, os potenciais fatores de risco (arcada, presen?a de bruxismo, for?a m?xima de mordida, propor??o coroa/implante (C/I) anat?mica e cl?nica, e ?rea da mesa oclusal) foram analisados com os desfechos: sobrevida dos implantes, perda ?ssea (linear) e falhas prot?ticas. No manuscrito 2, as reconstru??es tridimensionais do per?metro ?sseo mais pr?ximo ao implante foram realizadas no software Mimics? e convertidas em formato STL para exportar ao software Geomagic Studio?, onde foram sobrepostas, mensuradas volumetricamente. Resultados: No manuscrito 1 o tempo m?dio de acompanhamento cl?nico foi de 45 ? 9 (16; 57) meses. N?o houve perda precoce de implantes; ap?s o carregamento prot?tico ocorreram 4 perdas (sobrevida de 91,3%) e 13 complica??es prot?ticas (28,3%), gerando um ?ndice de sucesso de 65,2%. O termo de fragilidade demonstrou uma probabilidade 95% maior de perda na mand?bula em rela??o ? maxila. Observou-se perda ?ssea peri-implantar m?dia de 0,2 ? 0,4mm no primeiro ano, de 0,1 ? 0,2mm no segundo ano, de 0,1 ? 0,3mm no terceiro ano, e de 0,2 ? 0,4mm no quarto ano, com perda m?dia acumulada de 0,3 ? 0,5mm aos 48 meses. No modelo multin?vel os efeitos da propor??o C/I cl?nica (P<0,001) e do tempo (P<0,001) foram significativos sobre a perda ?ssea, estimando-se que para um aumento de uma unidade no tempo (12 meses) e de 0,1 na propor??o C/I cl?nica est? associada uma perda m?dia de 0,1mm para cada um dos fatores. Os demais potenciais fatores de risco n?o apresentaram rela??o estatisticamente significativa com os desfechos estudados. No manuscrito 2, a perda ?ssea m?dia volum?trica durante o primeiro ano em fun??o foi de 7,2 ? 6,1 mm3, durante o segundo ano em fun??o foi de 6,4 ? 7,8 mm3, e durante o per?odo acumulado de 2 anos em fun??o foi de 12,6 ? 8,0 mm3. Conclus?es: Os implantes de 6 mm, dentro das condi??es estudadas, s?o uma alternativa segura de tratamento para suportar coroas unit?rias na regi?o posterior dos maxilares. Contudo, a mand?bula apresenta maior risco de falhas. A taxa de complica??es prot?ticas foi mais alta que o reportado na literatura, por?m todas eram de f?cil resolu??o. Os fatores tempo e propor??o C/I cl?nico apresentaram-se como fatores preditores para perda ?ssea. Entretanto, essa pera situou-se dentro dos crit?rios de sucesso adotados pelo estudo. A mensura??o de altera??es ?sseas volum?tricas ao redor dos implantes parece ser poss?vel, desde que as imagens CBCT apresentem bom contraste e nitidez, principalmente quanto ao contorno do implante. Melhorias na qualidade das imagens e nos filtros de detec??o de tecido ?sseo seriam importantes para que tal metodologia se torne mais r?pida e de uso cl?nico.
14

S?ntese e caracteriza??o de comp?sitos tipo PLGA-apatita/biovidro macroporosos para aplica??es biom?dicas / Synthesis and characterization of macroporous composite type PLGA-apatite / bioglass for biomedical applications

Schardosim, Mariane Giacomini 29 August 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-10-17T15:52:43Z No. of bitstreams: 1 TES_MARIANE_GIACOMINI_SCHARDOSIM_COMPLETO.pdf: 4815510 bytes, checksum: c2182071d7270693c96a8dbc2f142391 (MD5) / Made available in DSpace on 2016-10-17T15:52:43Z (GMT). No. of bitstreams: 1 TES_MARIANE_GIACOMINI_SCHARDOSIM_COMPLETO.pdf: 4815510 bytes, checksum: c2182071d7270693c96a8dbc2f142391 (MD5) Previous issue date: 2016-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Bone injuries are a common form of trauma, being reported about 15 million fractures each year worldwide. Some of these lesions require the use of grafts to achieve bone regeneration. Currently, the main method used for treatment of these lesions is the use of autologous grafts. Although this technique is considered the gold standard of bone regeneration, there are some disadvantages such as the need for surgery to collect material and the lack of it. The application of composite biodegradable polymers such as poly (lactic-co-glycolic acid), calcium phosphates and bioactive ceramics such as apatite and bioglasses, represent an alternative in treatment of bone lesions. This is due to the possibility of combining characteristics of both materials. The objective of this research is to produce porous matrices PLGA:apatite/bioglass via two methodologies: salt leaching and lyophilization. The loads used in this study were synthesized by coprecipitation and evaluated by XRD, FTIR, SEM and DLS. The obtained porous structures are characterized by SEM, mercury porosimetry, compression, microtomography, in vitro degradation and in vitro biocompatibility. Highly porous composite scaffolds were obtained by the two methods studied. The load concentration and the type of load added to the polymeric matrix altered the mechanical properties and generated different surface features. Furthermore, the degradation rate of the supports is highly influenced by the added inorganic filler. / Danos ao tecido ?sseo s?o formas comuns de les?es, sendo reportadas cerca de 15 milh?es de fraturas a cada ano, em escala mundial. Parte destas les?es exige a utiliza??o de enxertos para regenera??o ?ssea. Atualmente, a principal metodologia utilizada para tratamento destas les?es ? a utiliza??o de enxertos aut?logos. Esta t?cnica ? considerada o padr?o ouro da regenera??o ?ssea, por?m, existem algumas desvantagens como a necessidade de uma cirurgia para coleta de material. A aplica??o de comp?sitos de pol?meros biodegrad?veis, como o ?cido poli (l?tico-co-glic?lico), fosfatos de c?lcio e cer?micas bioativas, como as apatitas e os biovidros, representa uma alternativa no tratamento de defici?ncias ?sseas. O objetivo desta pesquisa ? produzir matrizes porosas de PLGA: apatita/biovidro atrav?s de duas metodologias: lixivia??o de sal e liofiliza??o. As cargas utilizadas neste trabalho foram sintetizadas atrav?s de coprecipta??o e metodologia sol-gel e ent?o avaliadas por DRX, FTIR, MEV e DLS. As estruturas porosas obtidas foram caracterizadas por MEV, porosimetria a merc?rio, compress?o, microtomografia, degrada??o in vitro e biocompatibilidade in vitro. Foram obtidos arcabou?os comp?sitos altamente porosos atrav?s das duas metodologias estudadas. A concentra??o de carga e o tipo de carga adicionada a matriz polim?rica alteram as propriedades mec?nicas e diferentes caracter?sticas de superf?cie. Al?m disso, a velocidade de degrada??o dos arcabou?os ? altamente influenciada pela carga inorg?nica adicionada.
15

Avalia??o da neoforma??o ?ssea em defeitos cr?ticos com o uso de substitutos ?sseos derivados de fosfato e do PLGA/rhGH : estudo preliminar em coelhos

Boing, Fernanda 19 December 2014 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2017-03-17T14:57:19Z No. of bitstreams: 1 DIS_FERNANDA_BOING_COMPLETO.pdf: 1896690 bytes, checksum: 4b82835f573450cc33877741eeebac1f (MD5) / Made available in DSpace on 2017-03-17T14:57:19Z (GMT). No. of bitstreams: 1 DIS_FERNANDA_BOING_COMPLETO.pdf: 1896690 bytes, checksum: 4b82835f573450cc33877741eeebac1f (MD5) Previous issue date: 2014-12-19 / Objective: To evaluate the bone formation with different bone substitutes, including a rhGH hormone carrier (Growth Human Hormone Recombined) in an animal model. Materials and Methods: A total of 12 rabbits (from New Zealand), males, young adults (approximately 10 months old) were used. For each group, 6 rabbits were used, being that in each animal, 4 test sites were performed with a 8 mm diameter trephine, completing the total thickness of the skull. The test sites were distributed in: Group I (a: clot, b: autogenous bone triturated, c: PLGA (poly lactic glycolic acid) + rhGH (Growth Human Hormone Recombined), and d: autogenous bone + rhGH); and Group II (a: HA (hydroxyapatite), b: autogenous bone triturated, c: HA / ?-TCP (hydroxyapatite / tricalcium phosphate beta), and d: HA / SiO2n (hydroxyapatite / silicium oxide). The animals were sacrificed after 6 weeks and the samples were prepared and stained with HE (hematoxylin and eosin). A descriptive analysis of the samples was performed with OM (optics microscopic). Results: The evaluation showed that in the samples with PLGA and rhGH there was not the complete filling of the sites, although it was observed inflammatory process compatible with existing biomaterials. The bone formation regions presented filled osteocytic gaps in remodeling process, showing mature and viable bone. In relation to the sites with biomaterials (HA, HA/TCP-b e HA/ HA/SiO2n), all of them showed bone formation with biomaterial incorporation. Conclusion: The results of this study demonstrated the viability of different bone substitutes (HA, HA / TCP-?, HA / SiO2n). In addition, bone formation was not observed throughout the test region with the use of the hormone carrier. However, in regions with neoformation, it was verified the presence of mature and viable bone. / Objetivo: Avaliar a forma??o ?ssea com diferentes substitutos ?sseos, incluindo um carreador de horm?nio rhGH (horm?nio do crescimento) em defeitos cr?ticos em um modelo animal. Materiais e M?todos: Foram utilizados 12 coelhos da ra?a Nova Zel?ndia, machos, e adultos jovens (aproximadamente 10 meses). Para cada grupo foi utilizado 6 coelhos, sendo que em cada animal foram realizadas 4 cavidades teste com broca trefina de 8mm de di?metro e espessura total da calota craniana. As cavidades teste foram distribu?das em: Grupo I (a: co?gulo, b: osso aut?geno triturado, c: PLGA (Poli ?cido glic?lico l?tico) + rhGH (horm?nio do crescimento recombinante) e, d: osso aut?geno triturado + rhGH) e Grupo II (a: HA (hidroxiapatita), b: osso aut?geno triturado, c: HA/TCP-? (hidroxiapatita/tric?lcio fosfato beta) e d: HA/SiO2n (hidroxiapatita/?xido de sil?cio). Os animais foram sacrificados ap?s 6 semanas, e as amostras foram preparadas e coradas com colora??o HE (hematoxilina e eosina). Foi realizada uma an?lise descritiva das amostras por MO (microscopia ?ptica). Resultados: A avalia??o mostrou que nas amostras com PLGA e rhGH n?o houve o preenchimento total da cavidade, embora tenha sido observado neoforma??o ?ssea. Essas regi?es apresentavam-se com as lacunas osteoc?ticas preenchidas e em processo de remodela??o, evidenciando osso maduro e vi?vel. Com rela??o aos biomateriais (HA, HA/TCP-? ? ??/ HA/SiO2n), todos apresentaram forma??o ?ssea com a incorpora??o do biomaterial. Conclus?o: Os resultados do presente estudo demostraram a neoforma??o ?ssea com os diferentes substitutos ?sseos (HA, HA/TCP-?, HA/SiO2n). Al?m disso, foi observada a viabilidade do uso do carreador de horm?nio com a presen?a de osso maduro e vi?vel nas regi?es de teste desse.
16

Compara??o do estrato regenerante entre bordas e interior de uma floresta estacional semidecidual em Capelinha ? MG

Murta, Marco Aur?lio Cardoso 23 March 2016 (has links)
?rea de concentra??o: Conserva??o e restaura??o de ecossistemas. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2016-12-16T16:56:37Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) marco_aurelio_cardoso_murta.pdf: 1577952 bytes, checksum: bba2d96d1b722132b4b3335ae8d2a59e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-19T16:49:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) marco_aurelio_cardoso_murta.pdf: 1577952 bytes, checksum: bba2d96d1b722132b4b3335ae8d2a59e (MD5) / Made available in DSpace on 2016-12-19T16:49:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) marco_aurelio_cardoso_murta.pdf: 1577952 bytes, checksum: bba2d96d1b722132b4b3335ae8d2a59e (MD5) Previous issue date: 2016 / Companhia Energ?tica de Minas Gerais (CEMIG) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A Mata Atl?ntica ? considerada um dos biomas mais importantes do mundo, um hotspot para conserva??o, sendo as a??es antr?picas as principais fontes de dist?rbios que alteram este ambiente. A regenera??o natural ? um processo muito importante que atua diretamente sobre a recupera??o e fun??es do ecossistema. Este estudo teve como objetivo descrever e comparar a composi??o flor?stica-estrutural da regenera??o natural em uma Floresta Estacional Semidecidual localizada na RPPN Fazenda Fartura em Capelinha-MG. Para tal, foram amostrados um trecho no interior do fragmento (INT) e dois trechos de bordas, sendo uma em contato com pastagem (BP) e outra com cafeicultura (BC). Para analisar a diversidade alfa (?) foi utilizado o ?ndice de Shannon (H?) e equabilidade de Pielou (J?) e beta (?) pela similaridade flor?stica entre os trechos foi averiguada por meio de diagramas de Venn e dos ?ndices de Jaccard e Czekanowski. Foi elaborada uma curva esp?cie-?rea para estimar a dimens?o da riqueza flor?stica de cada trecho e calculados seus estimadores ?jackknife?. Para verificar poss?veis prefer?ncias das esp?cies ao longo dos trechos foi realizada uma An?lise de Esp?cies Indicadoras (ISA). Para analisar a estrutura da vegeta??o foram calculados os par?metros fitossociol?gicos cl?ssicos, al?m das distribui??es de di?metro e altura. As vari?veis estruturais foram comparadas por meio do teste de Kruskal-Wallis e a posteriori um teste de Dunn. Na amostragem total foram registrados 1.561 indiv?duos (230 no INT, 588 na BP e 743 na BC), identificados em 42 fam?lias bot?nicas, 87 g?neros e 162 esp?cies (78 no INT, 87 na BP e 89 na BC). As fam?lias com maior riqueza foram Myrtaceae, Fabaceae, Lauraceae, Rubiaceae, Melastomataceae e Annonaceae. Os resultados demonstraram que os trechos tem alt?ssima diversidade, muito acima do padr?o normalmente encontrado na literatura, com uma baixa similaridade flor?stica. De maneira geral, a estrutura da vegeta??o foi caracterizada por um maior n?mero de indiv?duos finos e pequenos. Os trechos apresentam ambientes distintos, cada um com diferentes hist?ricos de uso, variabilidade ambiental e tipos de dist?rbios, estes fatores possivelmente, foram os principais condicionantes que influenciaram os padr?es flor?sticos-estruturais da regenera??o natural na comunidade amostrada. As informa??es deste estudo evidenciaram a grande import?ncia da RPPN Fazenda Fartura para a conserva??o da Mata Atl?ntica, assim como, da necessidade de que mais estudos sejam realizados em escala espa?o-temporal. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The Atlantic Forest is considered one of the most important biomes of the world, a hotspot for conservation, and human actions are the main sources of disturbances that change this environment. Natural regeneration is a very important process that acts directly on the recovery and ecosystem functions. This study aimed to describe and compare the floristic-structural composition of natural regeneration in a Semideciduous Forest located in the RPPN Fazenda Fartura in Capelinha-MG. For this, we sampled a stretch inside the fragment (INT) and two sections of edges, one in contact with pasture (BP) and the other with coffee (BC). To analyze the diversity alpha (?), we used Shannon Index (H') and evenness of Pielou (J') and beta (?) through floristic similarity between sections was determined through Venn diagrams and indices of Jaccard and Czekanowski. We developed the species-area curve to estimate the size of the floristic richness of each sections and its estimators calculated ?jackknife?. To check for possible preferences of the species along the sections we performed Indicator Species Analysis (ISA). To analyze the structure of the vegetation, we calculated the classical phytosociological parameters, besides diameter and height distribution. We compared the structural variables through Kruskal-Wallis test and retrospectively a Dunn test. In the total sampling, we registered 1,561 individuals (230 in INT, 588 in BP and 743 in BC), identified in 42 botanical families, 87 genera and 162 species (78 in INT, 87 in BP and 89 in BC). Families with greater richness were Myrtaceae, Fabaceae, Lauraceae, Rubiaceae, Melastomataceae and Annonaceae. The results showed that the sections have high diversity, well above the standard normally found in the literature, with a low floristic similarity. In general, the vegetation structure was characterized by a higher number of thin and small individuals. The sections have different environments, each with different historical use, environmental variability and types of disturbances, these factors possibly were the main constraints that influenced the floristic-structural patterns of natural regeneration in the sampled community. The information from this study showed the importance of RPPN Fazenda Fartura for the conservation of the Atlantic Forest, as well as the need for more studies to be performed in a spatiotemporal scale.
17

Uso de sistema agroflorestal na implanta??o de reserva legal / Use of an agroforestry system for establishing Legal Reserve

Chauvet, Xavier Dominique Marie 01 August 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-02-07T16:42:52Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) xavier_dominique_marie_chauvet.pdf: 1433827 bytes, checksum: eb44d24d014598697e5f03f8775bdf4b (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-03-09T19:29:57Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) xavier_dominique_marie_chauvet.pdf: 1433827 bytes, checksum: eb44d24d014598697e5f03f8775bdf4b (MD5) / Made available in DSpace on 2018-03-09T19:29:57Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) xavier_dominique_marie_chauvet.pdf: 1433827 bytes, checksum: eb44d24d014598697e5f03f8775bdf4b (MD5) Previous issue date: 2017 / Estimativas indicam que 33% das terras agr?colas no mundo se encontram em algum est?gio de degrada??o, afetando principalmente a qualidade dos solos, a biodiversidade e a disponibilidade de ?gua. O Brasil concentra 140 milh?es de hectares de ?reas degradadas, dos quais 30 milh?es s?o pastagens com baix?ssima produtividade de alimento para os animais. A degrada??o do solo e dos ecossistemas nativos, bem como a dispers?o de esp?cies ex?ticas s?o as maiores e mais amplas amea?as ? biodiversidade. Em grande parte do pa?s o propriet?rio de um im?vel rural tem a obriga??o de registrar 20% da sua superf?cie como ?rea de Reserva Legal. Apesar da obrigatoriedade, em muitas propriedades ainda se verifica a sua inexist?ncia. Dentro do contexto da necessidade de implementa??o de Reserva Legal e da indisponibilidade de ?reas preservadas com vegeta??o nativa foi realizado um experimento em uma ?rea de pastagem degradada na qual se comparou o plantio isolado da aroeira do sert?o (Myracrodruon urundeuva Allem?o) com dois arranjos de sistema agroflorestal onde al?m da aroeira utilizaram-se como culturas anuais ou semi-perenes o feij?o guandu (Cajanus cajan (L) Hunth) e a mandioca (Manihot esculenta Crantz). O experimento foi implantado em ?rea de dom?nio do Bioma Cerrado. O delineamento estat?stico obedeceu ao modelo ?tipo leque? proposto por Nelder, (1962), onde analisou-se tr?s arranjos de plantio (aroeira a pleno sol, aroeira + feij?o guandu e aroeira + feij?o guandu + mandioca) em dez espa?amentos (555 a 3333 plantas de aroeira ha-1) completando 30 tratamentos. Ap?s 26 meses de implanta??o do experimento a sobreviv?ncia da aroeira foi de 100%, o crescimento da aroeira em altura, di?metro e cobertura de copa n?o foi influenciado pelos tratamentos e demostrou o car?ter calc?fila da esp?cie. A regenera??o arb?rea-arbustiva n?o foi favorecida pelo arranjo que continha aroeira, feij?o guandu e mandioca. A grande maioria da regenera??o arb?rea-arbustiva foi originada de brota??es de ra?zes pr?-existentes ? implanta??o do experimento. A regenera??o herb?cea foi influenciada pelo tipo de arranjo. O arranjo da aroeira a pleno sol permitiu a invas?o de Urochloa decumbens. O arranjo da aroeira, do feij?o guandu e da mandioca permitiu um excelente controle de herb?ceas invasoras, por?m limitou nesta fase inicial o desenvolvimento da regenera??o arbustiva-arb?rea. O arranjo com aroeira e feij?o guandu controlou a invas?o de Urochloa decumbens. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Estimates indicate that 33% of the world's agricultural land is in some stage of degradation, mainly affecting soil quality, biodiversity, and water availability. Brazil concentrates 140 million hectares of degraded areas, of which 30 million hectares are pastures with very low feed productivity. Degradation of native soil and ecosystems, and the dispersal of alien species are major and broader threats to biodiversity. The owner of a rural property has the obligation to register 20% of the area as a Legal Reserve area. Despite this obligation, in many ownerships the Legal reserve is non still existing. Within the context of the demand to recover degraded agricultural areas for the final implementation of Legal Reserve was carried out an experiment in an area of degraded pasture, in which an agroforestry system was compared with the isolated planting of an arboreal species. The arboreal species was Myracrodruon urundeuva Allem?o and the annual or semi-perennial crops were Cassava (Manihot esculenta Crantz) and Pigeon pea (Cajanus cajan (L) Hunth). The experiment was inserted in a typical Cerrado phytophysiognomy. The statistical design was based on Nelder's model (1962), where 3 plant arrangements (Aroeira, Aroeira + Pigeon pea and Aroeira + Pigeon pea + Cassava) were analyzed in 10 spacings (555 to 3333 Plants of aroeira.ha-1) completing 30 treatments. After 26 months of implantation, the survival rate of aroeira was 100%, the growth of the aroeira in height, diameter and crown cover was not influenced by treatments and expressed the calcific character of the species. The arboreal-shrub regeneration was not favored by the arrangement that contained Aroeira, Pigeon pea and Cassava. A great majority of the tree-shrub regeneration originated from rootstocks pre-existing to the implantation of the experiment. Herbaceous regeneration was influenced by the type of arrangement. The arrangement of the aroeira in full sun allowed the invasion of Urochloa decumbens. The arrangement of aroeira, pigeon pea and cassava allowed an excellent control of invasive herbaceous plants, but limited at this initial phase the development of tree-shrub regeneration. The arrangement with Aroeira and pigeon pea controlled an invasion of Urochloa decumbens.
18

Desativa??o e regenera??o de catalisadores zeol?ticos (HY E HZSM-5) utilizados em craqueamento catal?tico fluidizado (FCC)

Lima, Andresa Jaciane Cabral de 10 March 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-26T19:29:12Z No. of bitstreams: 1 AndresaJacianeCabralDeLima_DISSERT.pdf: 1971739 bytes, checksum: 742d6e447b4897c6982c80e42417ec21 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-28T23:20:37Z (GMT) No. of bitstreams: 1 AndresaJacianeCabralDeLima_DISSERT.pdf: 1971739 bytes, checksum: 742d6e447b4897c6982c80e42417ec21 (MD5) / Made available in DSpace on 2016-04-28T23:20:37Z (GMT). No. of bitstreams: 1 AndresaJacianeCabralDeLima_DISSERT.pdf: 1971739 bytes, checksum: 742d6e447b4897c6982c80e42417ec21 (MD5) Previous issue date: 2015-03-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O uso de catalisadores ? de fundamental import?ncia para ind?stria petrol?fera, tendo em vista que eles reduzem o tempo e a energia necess?rios para que uma rea??o aconte?a, melhorando a efici?ncia e a qualidade dos produtos. Em contra partida os mesmos acabam sofrendo desativa??o, que pode ser ocasionada por v?rios fatores, tais como: envenenamento dos s?tios ativos por metais, sinteriza??o e pela forma??o de coque, no qual provoca obstru??o nos poros causando assim a perda da fase ativa do material. Ap?s v?rios ciclos de uso e regenera??o, os catalisadores s?o dispostos na natureza tornando-se assim um grave problema ambiental. Diante dessa problem?tica o presente trabalho teve como objetivo desativar e regenerar ze?litas ?cidas dos tipos HZSM-5 e HY, a fim de comparar o comportamento das mesmas atrav?s das t?cnicas de: difratometria de Raios-X, Adsor??o de Desor??o de n-butilamina, An?lises Termogravim?tricas (TG/DTG) e espectroscopia na regi?o do infravermelho com transformada de Fourier. A desativa??o foi realizada em um reator de microatividade adaptado. Ap?s a rea??o foram obtidos os catalisadores desativados, e posteriormente realizada a regenera??o em um forno tipo mufla. Atrav?s das curvas termogravim?tricas de dessor??o de n-butilamina foi observado um aumento consider?vel na densidade de s?tios ?cidos m?dios da HZSM-5, provavelmente novos s?tios de adsor??o foram gerados durante a regenera??o. Observou-se tamb?m, que a ze?lita HZSM-5 apresentou cerca de 8% de coque, enquanto que a HY apresentou 18%, essa maior porcentagem se deu pelo fato da ze?lita faujasita (FAU) ser mais ?cida, e consequentemente promover mais rea??es, por tanto maior forma??o de coque. O coque formado em ambas as ze?litas tanto tiveram car?ter alif?ticos como arom?ticos. / The use of catalysts is of fundamental importance to the oil industry, given that they reduce the time and energy required for a reaction to take place, improving efficiency and product quality. In return they end up suffering deactivation, which can be caused by several factors such as: poisoning of active sites for metals, sintering and the formation of coke, which causes obstruction in the pores thus causing the loss of the active phase of the material. After several cycles of use and regeneration, the catalysts are arranged in nature thus becoming a serious environmental problem. Faced with this problem the present study aimed to disable and regenerate acidic zeolites of HZSM-5 and HY types in order to compare the behavior of the same through the techniques: Xray diffraction, adsorption of n-butyl amine Desorption, Analysis Thermogravimetric (TG / DTG) and spectroscopy in the infrared Fourier transform. Disabling was held in an adapted Micro activity reactor. After the reaction the deactivated catalysts were obtained, and then performed regeneration in a muffle furnace. Through the Thermogravimetric curves of n-butylamine desorption was observed a significant increase in the density of acid sites of HZSM-5 average probably new adsorption sites were generated during regeneration. It was also observed that the HZSM-5 zeolite showed about 8% of coke, while HY showed 18% higher this percentage was due to the fact that the zeolite faujasite (FAU) is more acidic, and thus promote further reaction, by the greater coke formation. The coke formed in both zeolites have both aliphatic as aromatic character.
19

Influ?ncia do c?lon na regenera??o hep?tica de ratos submetidos a hepatectomia e colectomia

Moreira, Marilia Daniela Ferreira de Carvalho 12 December 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-21T21:07:29Z No. of bitstreams: 1 MariliaDanielaFerreiraDeCarvalhoMoreira_TESE.pdf: 929428 bytes, checksum: 122ddbe6f0f95a006b02637a7a41c56e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-22T20:36:24Z (GMT) No. of bitstreams: 1 MariliaDanielaFerreiraDeCarvalhoMoreira_TESE.pdf: 929428 bytes, checksum: 122ddbe6f0f95a006b02637a7a41c56e (MD5) / Made available in DSpace on 2018-02-22T20:36:24Z (GMT). No. of bitstreams: 1 MariliaDanielaFerreiraDeCarvalhoMoreira_TESE.pdf: 929428 bytes, checksum: 122ddbe6f0f95a006b02637a7a41c56e (MD5) Previous issue date: 2017-12-12 / Estudos sobre a influ?ncia do c?lon na regenera??o hep?tica s?o escassos. Alguns t?m demonstrado que ap?s a colectomia ocorre aumento da regenera??o e sua redu??o em outros. Diante da controv?rsia, este trabalho visou examinar se a colectomia associada ? hepatectomia 70% influencia par?metros de regenera??o do f?gado em ratos. Foram utilizados 18 ratos Wistar distribu?dos em 3 grupos (6 animais cada). No grupo I (sham) foi realizada uma laparotomia com leve manipula??o de al?as; no grupo II uma colectomia + hepatectomia 70%; e no grupo III apenas hepatectomia 70%. No 6? dia p?s-operat?rio foi colhido sangue por pun??o card?aca sob anestesia, seguido de eutan?sia. Realizadas dosagens s?ricas de alanina aminotransferase (ALT), aspartato amino transferase (AST), fosfatase alcalina (FA), albumina, fator de crescimento de hepat?citos (HGF) e fator de crescimento transformador-? (TGF-?). A regenera??o do f?gado foi calculada pela f?rmula: (raz?o do peso do f?gado por 100g do peso corporal no momento da eutan?sia/peso do f?gado no pr?-operat?rio projetado por 100g de peso corporal) ? 100. Os testes de an?lise de vari?ncia (ANOVA) e Tukey foram usados, com signific?ncia p<0,05. Resultados: Houve uma menor e significante magnitude dos n?veis de ALT e AST no grupo II comparados com o grupo III (p<0,001). A albuminemia mostrou n?veis significativamente mais elevados no grupo II que no III. Os n?veis de HGF (408?18,2 pg/mL) e TGF-? (3,8?0,3 ng/mL) no grupo II foram significativamente mais elevados que o HGF (360?58,6 pg/mL) e TGF-? (2,3?0,4 ng/mL) no grupo III, respectivamente (p<0,001). O percentual de regenera??o hep?tica foi significativamente mais elevado no grupo II, do que no grupo III (p=0,003). Em conclus?o, este estudo concluiu que a colectomia realizada simultaneamente ? hepatectomia 70% influenciou positivamente na regenera??o do f?gado em ratos. Pesquisas adicionais s?o necess?rias para revelar os mecanismos moleculares deste efeito e para caracterizar a influ?ncia do c?lon na fisiologia do f?gado. / Studies on the influence of the colon on liver regeneration are scarce. Some have shown that after colectomy there is an increase in regeneration and its reduction in others. Faced with the controversy, this work aimed to investigate whether colectomy simultaneously performed with 70% hepatectomy influences liver regeneration in rats. Eighteen Wistar rats were distributed in 3 groups, 6 animals each. In group I (sham) only laparotomy was performed with mild manipulation of boweld loops; in group II 70% hepatectomy and simultaneous colectomy; in group III only 70% hepatectomy. On the 6th postoperative day, blood was collected by cardiac puncture under anesthesia, and remaining liver was removed. Serum measures of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (FA), albumin, hepatocyte growth factor (HGF) and transforming growth factor-? (TGF-?) were performed. Liver regeneration was calculated by (liver weight per 100g of the body weight at sacrifice/preoperative projected liver weight per 100g of the body weight) ? 100. The Analyses of variance (ANOVA) and Tukey tests were used, with significance p<0.05. There was significant lower levels of ALT and AST in group II rats when compared to group III (p<0.001). Albuminemia showed significantly higher levels in group II rats than in III (p<0.01). Serum levels of HGF (408?18.2pg/mL) and TGF-? (3.8?0.3ng/mL) were significantly higher in group II rats than HGF (360?58.6pg/mL), TGF-? (2.3?0.4ng/mL) in group III, respectively. The percentage of liver regeneration was significantly higher in group II than in group III (p = 0.003). In conclusion, this study demonstrated that colectomy, performed simultaneously with 70% hepatectomy, positively influenced liver regeneration in rats. Further research is needed to reveal the molecular mechanisms of this effect and to characterize the effects of the colon on liver physiology.
20

A utiliza??o de c?lulas-tronco mesenquimais adipog?nicas e acido hialur?nico como composto celular para engenharia tecidual ?ssea : estudo in vivo

Boeckel, Daniel Gon?alves 19 December 2016 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-29T15:00:54Z No. of bitstreams: 1 TES_DANIEL_GONCALVES_BOECKEL_PARCIAL.pdf: 676511 bytes, checksum: cb9dde990f100982c7eac5a144973b47 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-29T15:01:09Z (GMT) No. of bitstreams: 1 TES_DANIEL_GONCALVES_BOECKEL_PARCIAL.pdf: 676511 bytes, checksum: cb9dde990f100982c7eac5a144973b47 (MD5) / Made available in DSpace on 2017-06-29T15:01:17Z (GMT). No. of bitstreams: 1 TES_DANIEL_GONCALVES_BOECKEL_PARCIAL.pdf: 676511 bytes, checksum: cb9dde990f100982c7eac5a144973b47 (MD5) Previous issue date: 2016-12-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The present research aims to characterize the mesenchymal stem cells of adipose origin (MSCAs) and to evaluate its use on the scaffold of hyaluronic acid (HA) as a cellular compound for bone tissue engineering. Firstly, cell characterization was performed through the collection of epididymal adipose tissue, isolation, culture and in vitro expansion. Through the morphological analysis of MSCAs culture it was possible to confirm elongated fusiform characteristic, centralized nucleus, extensions and adhesion to the plastic bottle. Expansion analysis also demonstrated a high cell proliferative index during the 26 days of in vitro culture. The Flow Cytometry test allowed the identification of the main surface markers that characterize the mesenchymal stem cells (CD29 and CD90) and negative for hematopoietic markers (CD31 and CD45). Moreover, MSCAs when induced to adipogenic and osteogenic media showed plasticity, since they were able to differentiate into adipocytes and osteoblasts respectively. The cell viability test was also performed in vitro, through the M.T.T (mitochondrial activity) of MSCAs on the HA scaffold. Concentrations of 100%, 75%, 50%, 25% and 15% were evaluated on the HA scaffold at times of 24, 48 and 72 hours. The results have shown cellular viability above 60% in almost all times and concentrations. Then, 50 critical bone defects were performed in the femoral region with 2 mm in diameter (one defect per femur) in 25 Lewis rats. The grafting treatments were divided as follows: I-negative control / only the defect (C); II-HA Scaffold; III- MSCAs; IV- MSCAs + HA and V- MSCAs previously osteoinduced + HA. After 23 days the rats were euthanized and had 5 femurs used for the microtomographic (?-CT) and histomorphometric analysis and 5 femurs used for the RT-PCR (Real-Time Polymerase Chain Reaction) analysis. The results for the ?-CT tests in the volume of osseous tissue parameter (VOT) and the percentage of osseous tissue (POT) did not present statistical differences among all groups. However, on the osseous contact surface (SCO) and osseous surface density (DSO) parameters, we had groups IV, III and V with higher indexes and differing statistically from the negative control groups I and group II. In histomorphometry we also had groups IV, V and III with greater area of regenerated bone tissue and differing with significance from groups I and II. The results were analyzed statistically by Analysis of Variance one way (ANOVA) and the level of significance was 5% (p <0.05). Regarding RT-PCR, a statistically significant difference was observed only when we evaluated osteonectin (ON) in which group II and V were more expressive in relation to groups III and IV. Regarding osteopontin (OP) and Type I collagen (Col1A), no differences were identified among the treated groups. The results were analyzed using Kruskal-Wallis non-parametric test and the significance level set was 5% (p <0.05). / A presente pesquisa tem por objetivo caracterizar as c?lulas-tronco mesenquimais de origem adiposa (CTMAs) e avaliar seu uso sobre a matriz de ?cido hialur?nico (AH) como composto celular para engenharia tecidual ?ssea. Primeiramente, foi realizada a caracteriza??o celular atrav?s da coleta do tecido adiposo epididimal, isolamento, cultivo e expans?o in vitro. Atrav?s da an?lise morfol?gica da cultura das CTMAs foi poss?vel confirmar caracter?stica fusiforme alongada, n?cleo centralizado, prolongamentos e ades?o ? garrafa pl?stica. A an?lise de expans?o tamb?m comprovou um alto ?ndice proliferativo celular, durante os 26 dias de cultura in vitro. J? o teste de citometria de fluxo permitiu a identifica??o dos principais marcadores de superf?cie que caracterizam as c?lulas-tronco mesenquimais (CD29 e CD90) e sendo negativo para marcadores hematopoi?ticos (CD31 e CD45). As CTMAS tamb?m quando induzidas aos meios adipog?nico e osteog?nico mostraram plasticidade, j? que foram capazes de diferenciarem-se em adip?citos e osteoblastos, respectivamente. Ainda in vitro, foi realizado o teste de viabilidade celular atrav?s do MTT (atividade mitocondrial), ap?s o contato das CTMAs sobre a matriz de AH. As concentra??es de 100%, 75%, 50%, 25% e 15% foram avaliadas sobre a matriz de AH nos tempos de 24, 48 e 72 horas. Os resultados comprovaram uma viabilidade celular acima de 60% em quase todos os tempos e concentra??es. Em seguida, foram realizados 50 defeitos ?sseos cr?ticos (DOC) na regi?o femoral com 2 mm de di?metro (um defeito por f?mur) em 25 ratos Lewis. Os tratamentos de enxertia realizados foram divididos da seguinte forma: I-controle negativo / apenas o defeito (C); II- matriz AH; III-CTMAs; IV-CTMAs + AH e V- CTMAs osteoinduzida + AH. Ap?s 23 dias os ratos sofreram eutan?sia e tiveram 5 f?mures utilizados para as an?lises microtomogr?ficas (?-CT) e histomorfom?trica e 5 f?mures utilizados para a an?lise por RT-PCR (Rea??o em cadeia da Polimerase em tempo Real). Os resultados para os testes por ?-CT no par?metro volume de tecido ?sseo (VTO) e porcentagem de tecido ?sseo (PTO) n?o apresentaram diferen?as estat?sticas entre todos os grupos. J?, nos par?metros superf?cie de contato (SCO) e densidade de superf?cie ?ssea (DSO) tivemos o grupo IV, III e V com maiores ?ndices e diferindo estatisticamente dos grupos controle negativo I e do grupo II. Na histomorfometria tamb?m tivemos os grupos IV, V e III com maiores ?reas de tecido ?sseo regenerado e diferindo com signific?ncia dos grupos I e II. Os resultados foram analisados estatisticamente pela An?lise de Vari?ncia de uma via (ANOVA) o n?vel de signific?ncia estabelecido foi de 5% (p < 0,05). Em rela??o ao RT-PCR, observou-se diferen?a estatisticamente significante apenas quando foi avaliada osteonectina (ON), sendo que o grupo II e V apresentaram maior express?o em rela??o aos grupos III e IV. Em rela??o ? osteopontina (OP) e ao col?geno Tipo I (Col1A) n?o foram identificadas diferen?as entres os grupos tratados. Os resultados foram analisados atrav?s do teste n?o param?trico de Kruskal-Wallis e o n?vel de signific?ncia estabelecido foi de 5% (p < 0,05).

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