RESUMEN
While hyaluronic acid encapsulating superparamagnetic iron oxide nanoparticles have been reported to exhibit selective cytotoxicity toward cancer cells, it is unclear whether low-molecular-weight hyaluronic acid-conjugated superparamagnetic iron oxide nanoparticles also display such cytotoxicity. In this study, high-molecular-weight hyaluronic acid was irradiated with γ-ray, while Fe3O4 nanoparticles were fabricated using chemical co-precipitation. The low-molecular-weight hyaluronic acid and Fe3O4 nanoparticles were then combined according to a previous study. Size distribution, zeta potential, and the binding between hyaluronic acid and iron oxide nanoparticles were examined using dynamic light scattering and a nuclear magnetic resonance spectroscopy. The ability of the fabricated low-molecular-weight hyaluronic acid conjugated superparamagnetic iron oxide nanoparticles to target cancer cells was examined using time-of-flight secondary ion mass spectrometry and T2* weighted magnetic resonance images to compare iron signals in U87MG human glioblastoma and NIH3T3 normal fibroblast cell lines. Comparison showed that the present material could target U87MG cells at a higher rate than NIH3T3 control cells, with a viability inhibition rate of 34% observed at day two and no cytotoxicity observed in NIH3T3 normal fibroblasts during the three-day experimental period. Supported by mass spectrometry images confirming that the nanoparticles accumulated on the surface of cancer cells, the fabricated materials can reasonably be suggested as a candidate for both magnetic resonance imaging applications and as an injectable anticancer agent.
RESUMEN
Ameloblastoma is a benign but locally invasive neoplasm of the odontogenic epithelium that tends to grow slowly in the mandible or maxilla. It can be highly destructive to the surrounding dental anatomy and can cause death by progressive spread to nearby vital structures in rare cases. Marginal resection is the most effective method of eliminating the tumor, but treatment can further contribute to oral and dental deformity and malfunction. This clinical report describes the dental rehabilitation of a young adult patient diagnosed with ameloblastoma and underwent preliminary marsupialization, segmental mandibulectomy, and fibula free flap reconstruction, followed by mandibular dental implant placements. Orthodontic and rapid palatal expansion for maxillary arch correction was also performed. The treatment goal of regaining dental function and a satisfactory appearance was accomplished.
RESUMEN
This study applied poly-ε-caprolactone (PCL), a biomedical ceramic powder as an additive (nano-hydroxyapatite (nHA) or ß-tricalcium diphosphate (ß-TCP)), and sodium chloride (NaCl) and ammonium bicarbonate ((NH4)HCO3) as porogens; these stuffs were used as scaffold materials. An improved solvent-casting/particulate-leaching method was utilized to fabricate 3D porous scaffolds. In this study we examined the physical properties (elastic modulus, porosity, and contact angle) and degradation properties (weight loss and pH value) of the 3D porous scaffolds. Both nHA and ß-TCP improved the mechanical properties (elastic modulus) of the 3D porous scaffolds. The elastic modulus (0.15~1.865 GPa) of the various composite scaffolds matched that of human cancellous bone (0.1~4.5 GPa). Osteoblast-like (MG63) cells were cultured, a microculture tetrazolium test (MTT) was conducted and alkaline phosphatase (ALP) activity of the 3D porous scaffolds was determined. Experimental results indicated that both nHA and ß-TCP powder improved the hydrophilic properties of the scaffolds. The degradation rate of the scaffolds was accelerated by adding nHA or ß-TCP. The MTT and ALP activity tests indicated that the scaffolds with a high ratio of nHA or ß-TCP had excellent properties of in vitro biocompatibility (cell attachment and proliferation).
