RESUMEN
The development of polymeric blends to be used as matrices for bone regeneration is a hot topic nowadays. In this article we report on the blends composed by corn starch and poly(vinylidene fluoride), PVDF, or poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), to obtain biocompatible materials. Blends were produced by compressing/annealing and chemically/structurally characterized by micro-Raman scattering and Fourier transform infrared (FTIR) absorption spectroscopies, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM), besides in vivo study to evaluate the tissue response. Vibrational spectroscopy reveals no chemical interaction between the polymers and starch, absence of material degradation due to compressing/annealing process or organism implantation, and maintenance of α and ferroelectric crystalline phases of PVDF and P(VDF-TrFE), respectively. As a consequence of absence of interaction between polymers and starch, it was possible to identify by SEM each material, with starch acting as filler. Elastic modulus (E') obtained from DMA measurement, independent of the material proportion used in blends, reaches values close to those of cancellous bone. Finally, the in vivo study in animals shows that the blends, regardless of the composition, were tolerated by cancellous bone.
Asunto(s)
Materiales Biocompatibles/química , Polímeros de Fluorocarbono/química , Prótesis e Implantes , Almidón/química , Zea mays/química , Amilopectina/química , Amilosa/química , Animales , Módulo de Elasticidad , Masculino , Microscopía Electrónica de Rastreo , Ratas , Ratas Wistar , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría RamanRESUMEN
Cytotoxicity and subcutaneous tissue reaction of innovative blends composed by polyvinylidene fluoride and polyvinylidene fluoride-trifluoroethylene associated with natural polymers (natural rubber and native starch) forming membranes were evaluated, aiming its applications associated with bone regeneration. Cytotoxicity was evaluated in mouse fibroblasts culture cells (NIH3T3) using trypan blue staining. Tissue response was in vivo evaluated by subcutaneous implantation of materials in rats, taking into account the presence of necrosis and connective tissue capsule around implanted materials after 7, 14, 21, 28, 35, 60, and 100 days of surgery. The pattern of inflammation was evaluated by histomorphometry of the inflammatory cells. Chemical and morphological changes of implanted materials after 60 and 100 days were evaluated by Fourier transform infrared (FTIR) absorption spectroscopy and scanning electron microscopy (SEM) images. Cytotoxicity tests indicated a good tolerance of the cells to the biomaterial. The in vivo tissue response of all studied materials showed normal inflammatory pattern, characterized by a reduction of polymorphonuclear leukocytes and an increase in mononuclear leukocytes over the time (p < 0.05 Kruskal-Wallis). On day 60, microscopic analysis showed regression of the chronic inflammatory process around all materials. FTIR showed no changes in chemical composition of materials due to implantation, whereas SEM demonstrated the delivery of starch in the medium. Therefore, the results of the tests performed in vitro and in vivo show that the innovative blends can further be used as biomaterials.
Asunto(s)
Fibroblastos/metabolismo , Hidrocarburos Fluorados/farmacología , Leucocitos Mononucleares/metabolismo , Ensayo de Materiales , Polivinilos/farmacología , Almidón/farmacología , Compuestos de Vinilo/farmacología , Animales , Regeneración Ósea/efectos de los fármacos , Fibroblastos/patología , Hidrocarburos Fluorados/efectos adversos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Leucocitos Mononucleares/patología , Masculino , Ratones , Células 3T3 NIH , Polivinilos/efectos adversos , Ratas , Ratas Wistar , Almidón/efectos adversos , Compuestos de Vinilo/efectos adversosRESUMEN
Objetivo: Este trabalho teve por objetivo caracterizar os pacientes e as atividades realizadas no Projeto Hemiplegia, que consiste em encontros de portadores de hemiplegia para realização de fisioterapia em grupo. Método: A caracterização dos pacientes foi feita por meio da análise de seus prontuários e da aplicação da Escala de Equilíbrio de Berg (EEB), e a descrição do projeto pela análise da filmagem de 18 sessões do projeto. Resultados: Dos pacientes analisados 15 pertenciam ao sexo masculino e 4 ao feminino, com idade média de59,63 ± 11,1 anos. O tempo médio de seqüela pós-AVC foi de 5,17 ± 3,92 anos. As médias alcançadas nas avaliações da EEB foram 43,00 ± 10,48 pontos na 1ª avaliação e 44,95 ± 9,69 pontos na 2ª avaliação. A análise comparativa entre as duas avaliações determinou que houve diferença estatística significativa entre elas(p<0,05). A conduta fisioterapêutica caracteriza-se pela utilização de exercícios ativos, alongamentos, exercícios de equilíbrio e coordenação e atividades lúdicas. Conclusão: O Projeto Hemiplegia demonstra que a terapia em grupo pode ser uma boa opção terapêutica capaz de impedir complicações que possam determinar uma maior deterioração da capacidade funcional e da dependência, também garante a manutenção ou melhora do equilíbrio, melhorando assim a qualidade de vida desses pacientes.
Objective: The aim of this study was to characterize the patients and the physical activities performed in theHemiplegia Project. This project consisted of a group of hemiplegic patients that get together to performgroup physical therapy. Method: The profile of the patients was made through the analysis of their medicalrecords and the use of Berg balance scale. The outline of the project was made by analyzing the recordingimages of 18 sessions of the program. Results: Of the 19 patients enrolled, 15 were male and 4 female. Meanage was 59.63 ± 11.1 years. The median known duration of sequela after a stroke (CVA) was 5.17 ± 3.92 years.The average scores reached in the BBS evaluations were 43.00 ± 10.48 points in 1st evaluation and 44.95 ± 9.69points in 2nd evaluation. A comparative analysis was performed to test differences between the two evaluations.There were no significant statistical differences between the two evaluations (p £ 0.05). The average time ofsequel after AVC was 5.17 ± 3.92 years. The physical therapy session is characterized for the use of activeexercises, stretching, equilibrium and motor coordination exercises, and playful activities. Conclusion: TheHemiplegia Project demonstrates that the group therapy can be a good therapeutical option to preventcomplications that may determine a much large deterioration of the functional capacity and the dependence.Also the group therapy assures the maintenance of the equilibrium or improves it, thus improving the qualityof life of these patients.