ABSTRACT
Objective@#To investigate the effect of pure titanium surface of large diameter TiO2 nanotubes modified by RGD peptide on the adhesion and proliferation of MG63 osteoblasts. to provide theoretical proof for developing titanium implants.@*Methods@#Commercially pure titanium discs were divided into four groups and treated with SLA to obtain a microrough surface (SLA group). Then, nanotubes were imposed on this microrough surface by anodization (SLA+80 group). The surface was then modified by dopamine (DOPA) (DOPA Group), after which bioactive RGD peptide layers were generated on the TiO2 nanotube surfaces via electrochemical and molecular self-assembly techniques (RGD group). The titanium surface morphology and elemental composition of each group were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). MG63 cells were cultured in vitro to evaluate biological activities of titanium before and after treatment, including the evaluation of early-stage cell adhesion capacity by fluorescence microscopy, proliferation capacity by MTS assay, and mRNA expression of the cell osteoblast-related genes alkaline phosphatase (ALP) and osteocalcin (OCN) by qRT-PCR.@*Results@#FE-SEM and XPS showed that hierarchical micro/nanosurfaces decorated with TiO2 nanotubes were produced on titanium using sandblasting and large grit etching combined with anodization, dopamine was then self-polymerized to form a polydopamine film on the TiO2 nanotube surfaces, and RGD peptides were then conjugated to the polydopamine film, finally forming RGD peptide-modified bioactive layers. In vitro experiments showed that compared with the other three materials, the RGD-modified material was more conducive to cell adhesion and proliferation (P < 0.05). The expression levels of ALP and OCN mRNA in the RGD group were significantly higher than those in the SLA group and DOPA group (P < 0.05).@*Conclusion@#Hierarchical micro/nanosurfaces decorated with TiO2 nanotubes functionally modified with RGD peptides have good biocompatibility and could be used for developing titanium implants and further improving early osseointegration.
ABSTRACT
Objective@#To evaluate the expression of HAase in Oral Squamous Cell Caricinoma (OSCC). @*Methods @# The distribution and expression of HAase in 21 patients with OSCC and their resecetions with tumor-free margins were examined by immunohistochemistry method.@*Results@#HAase were mainly immunostained in tumor tissue. The expression of HAase in oral cancer with nodal metastasis and low pathological grades were higher than that with no nodal metastasis and high pathological grades (P < 0.05), whereas no difference between the TNM stages (P > 0. 05). @*Conclusion @#The HAase levels were high in oral squamous cell carcinoma tissues, and rising in patients with lymph node metastasis and poorly differentiated.