RESUMO
Synthetic hydroxyapatite nanorods are excellent candidates for bone tissue engineering applications. In this study, hydroxyapatite nanorods resembling bone minerals were produced by using soft-template method with cetyltrimethylammonium bromide. Composite hydroxyapatite/poly(D, L)lactic acid films were prepared to evaluate the prepared hydroxyapatite nanorods in terms of cell affinity. Preliminary in vitro experiments showed that aspect ratio and film surface roughness play a vital role in controlling adhesion and proliferation of human osteoblast cell line MG 63. The hydroxyapatite nanorods with aspect ratios in the range of 5.94-7 were found to possess distinctive properties, with the corresponding hydroxyapatite/poly(D, L)lactic acid films promoting cellular confluence and a fast formation of collagen fibers as early as after 7 days of culture.
Assuntos
Substitutos Ósseos/química , Durapatita/química , Nanotubos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Substitutos Ósseos/síntese química , Adesão Celular , Linhagem Celular , Proliferação de Células , Colágeno/biossíntese , Durapatita/síntese química , Humanos , Ácido Láctico/síntese química , Ácido Láctico/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanotubos/ultraestrutura , Osteoblastos/citologia , Osteoblastos/metabolismo , Poliésteres , Polímeros/síntese química , Polímeros/química , Engenharia TecidualRESUMO
OBJECTIVES: To understand influences on diet among low-income African-American adolescents in East Baltimore. METHODS: Formative research was conducted for a food store-centered healthy diet intervention targeted to inner-city youth. Family, school and neighborhood influences on eating habits and health concepts were explored. RESULTS: Family structure, economic resources and past experiences influence what food means to adolescents. Healthy food in school and local stores is limited. Terminology to categorize foods was identified, including the term "home foods". CONCLUSIONS: Suggested adolescent nutritional interventions include promotion of home-based eating, improving availability of healthy foods in school and neighborhood stores, and targeted educational materials.