To evaluate the cell responses of titanium oxide layer with the nanoporous micro-structure, an electrochemical anodization approach was proposed to create a nanoporous structure that superimposed onto the moderately rough sand-blasted, large-grit, acid-etched (SLA) Ti surface (denoted as SLAffinity-Ti). The osteoblast-like cells were cultured on SLAffinity-Ti and un-treated surfaces. Cell adhesion, viability, mRNA expressions as well as the productions of alkaline phosphatase (ALP) and osteocalcin (OC) were evaluated at predetermined intervals. The present results showed that cells had a high viability, attachment, and improved cell proliferation at day 7 and 14 when cultured on SLAffinity-Ti surface. The mRNA expressions of ALP and OC were upregulated while the type I collagen was not influenced. Additionally, the cells cultured on the SLAffinity-Ti surface produced a higher level of ALP and OC relative to cells on untreated surfaces. These findings confirmed that surface topography (nanoporous roughness) and TiO 2 layers influenced the cell responses and the study revealed that cells grown on SLAffinity-Ti may improve osseointegration for Ti implants.

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This study investigated the thermal injury and adhesion property of a novel electrosurgery of liver using copper-doped diamond-like carbon (DLC-Cu) surface treatment. It is necessary to reduce the thermal damage of surrounding tissues for clinical electrosurgeries. The surface morphologies of stainless steel (SS) coated with DLC (DLC-Cu-SS) films were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Bionic liver models were reconstructed using magnetic resonance imaging (MRI) to simulate electrosurgery. Cell cytotoxicity assays showed that the DLC-Cu thin film was nontoxic. The temperature of tissue decreased significantly with use of the electrosurgical device with nanostructured DLC-Cu films and increased with increasing thickness of the films. Thermography revealed that the surgical temperature in the DLC-Cu-SS electrosurgical device was significantly lower than that in the untreated device in the animal model. Moreover, compared to the SS electrosurgical device, the DLC-Cu-SS electrosurgical device caused a relatively small injury area and lateral thermal effect. The results indicate that the DLC-Cu-SS electrosurgical device decreases excessive thermal injury and ensures homogeneous temperature transformation in the tissues.

The purpose of the present study is to investigate the effects of stenoses on the flow vector and vascular wall stress using angiographic examination and threedimensional (3-D) computer-aided analysis. Nine volunteers with stenoses in hearts and arms were enrolled, and three volunteers were enrolled as the control group. In total, nine 3-D artery models were reconstructed from magnetic resonance images to simulate blood hemodynamic behaviors. Several studies have employed 3-D finite element artery models, but few have examined the effects of hemodynamic behavior in arteries with the stenoses. The results showed that stenoses decreased the blood flow velocity by approximately 40% and confirmed that stenoses also induce abnormal stress where the vessel wall is thinnest. The results of the computer-aided model flow vectors are similar to, but smaller than, those from the angiographic examination. As described above, the present study provides information regarding stenoses for clinical diagnosis and treatment.

The objective of the present research was to investigate the thermal injury in the brain after minimally invasive electrosurgery using instruments with copper-doped diamond-like carbon (DLC-Cu) surface coating. The surface morphologies of DLC-Cu thin films were characterized using scanning electron microscopy and atomic force microscopy. Three-dimensional brain models were reconstructed using magnetic resonance imaging to simulate the electrosurgical operation. In adult rats, a monopolar electrosurgical instrument coated with the DLC-Cu thin film was used to generate lesions in the brain. Animals were sacrificed for evaluations on postoperative days 0, 2, 7, and 28. Data indicated that the temperature decreased significantly when minimally invasive electrosurgical instruments with nanostructure DLC-Cu thin films were used and continued to decrease with increasing film thickness. On the other hand, the DLC-Cu-treated device created a relatively small thermal injury area and lateral thermal effect in the brain tissues. These results indicated that the DLC-Cu thin film minimized excessive thermal injury and uniformly distributed the temperature in the brain. Taken together, our study results suggest that the DLC-Cu film on copper electrode substrates is an effective means for improving the performance of electrosurgical instruments.