Electrochemical Deposition of Hydroxyapatite Substituted with Magnesium and Strontium on Ti-6Al-4V Alloy.

In the present study, electrochemical deposition of hydroxyapatite substituted with magnesium and strontium on Ti-6Al-4V alloy have investigated. Mg and Sr-doped HAp was coated using subsequently pulsed electrochemical deposition process at 85 °C in the solution contained Ca, Mg, Sr, and P ion. The morphology of Mg/Sr-HAp formed on implant was investigated using scanning electron microscopy and X-ray diffraction.

Thymosin 4 Reduces H₂O₂ Induced Oxidative Stress in MC3T3-E1 Cells on Titanium Surface.

Thymosin β4 (Tβ4) is known to inhibit an inflammatory response and to increase the survival of osteoblasts on titanium (Ti) surfaces. Ti is the most widely used graft material in dentistry; however, an inflammatory response induced following implant placement results in the generation of reactive oxygen species (ROS). The oxidative stress from the production of ROS such as nitric oxide (NO) and hydrogen peroxide (H2O2) can damage surrounding cells, resulting in implant failure by decreasing cell viability.

Bone cement with a modified polyphosphate network structure stimulates hard tissue regeneration.

In this study, a calcium polyphosphate cement (CpPC) consisting of basic components was investigated to assess its potential for hard tissue regeneration. The added basic components for improving the structural stability, which controlled the setting time, where the setting reaction resulted in the formation of amorphous structure with a re-constructed polyphosphate. Moreover, the characteristics were controlled by the composition, which determined the polyphosphate structure.

O2/Ar Plasma Treatment for Enhancing the Biocompatibility of Hydroxyapatite Nanopowder and Polycaprolactone Composite Film.

In this study we performed O2/Ar plasma treatment to remove the polycaprolactone on hydroxyapatite nanopowder and polycaprolactone (HAp-NP/PCL) composite film. After plasma ashing, the HAp-NP was exposed on the composite film. The 25 wt% HAp-NP/PCL treated with plasma showed the hydrophilic surface property with reducing the aging effect.

Plasma Polymerization of 1,2-Diaminocyclohexane for Covalent Bonding of Bone Morphogenic Protein-2 on Titanium Surface.

Among the bone morphogenic protein (BMP) family members, BMP-2 is a potent osteoinductive factor that plays key roles during bone formation. In this study, plasma polymerization of 1,2-diaminocyclohexane (DACH) was performed to immobilize the BMP-2 on Ti surface. The plasma polymerization of DACH was carried out at a discharge power of 60 W and 100 W under a pressure of 10 mTorr for 90 sec.

In Vitro Antibacterial Activity of Nano Silver Ion Substituted Poly Acrylic Acid Films on Titanium by Plasma Polymerization.

Antibacterial activity of oral pathogens such as Streptococcus mutans, Streptococcus sobrinus when silver ion immobilized on commercially pure (CP) titanium (Ti) surface was investigated in this study. Plasma-polymerized acrylic acid to have carboxyl group was deposited on CP-Ti surface and then ion-exchanged with Ag+ ions in 0.1 N AgNO3.

Secretory Leukocyte Protease Inhibitor (SLPI) Increases Focal Adhesion in MC3T3 Osteoblast on Titanium Surface.

An appropriate interaction between implanted materials and the surrounding tissue is essential for successful implantation. Titanium (Ti) and some of its alloys have been used in dentistry and orthopedics as a substitutive material for hard tissue, such as teeth or natural bone. Nevertheless, metal ions released from titanium and alloy implants have adverse biological effects on biological tissues or cells.

Oxygen and Nitrogen Gas Plasma Surface Treatments on Titanium for Initial Adhesion and Proliferation of Preosteoblast Cells.

In this study, titanium (Ti) surface was treated through the use of oxygen and nitrogen plasma for improving the initial adhesion and proliferation of preosteoblast cells. The plasma treated Ti surface demonstrated hydrophilic surface property and promoted initial adhesion and proliferation of preosteoblast cells.

Characteristics of Plasma Treated Electrospun Polycaprolactone (PCL) Nanofiber Scaffold for Bone Tissue Engineering.

Polycaprolactone (PCL) nanofibers (PCL-NF) with uniform fibrous structure were fabricated by electrospinning. However, PCL-NF has hydrophobic surface, lacks functional groups and hence it is not a good substrate for cell adhesion. To improve the cell adhesion, PCL-NF surfaces were modified by low pressure RF discharge plasma treatment using monomer such as acrylic acid or oxygen gas.

Bone Tissue Engineering by Using Calcium Phosphate Glass Scaffolds and the Avidin-Biotin Binding System.

Highly porous and interconnected scaffolds were fabricated using calcium phosphate glass (CPG) for bone tissue engineering. An avidin-biotin binding system was used to improve osteoblast-like cell adhesion to the scaffold. The scaffolds had open macro- and micro-scale pores, and continuous struts without cracks or defects.

Engineered microstructure granules for tailored drug release rate.

Biomaterials developed for controlled drug delivery have demonstrated excellent results in the present study. A biomaterial prepared using hydroxyapatite (HAp) was shown to have a hollow structure with the presence of interconnected pores to house drug carriers. The poly(lactic-co-glycolic acid) particles were used as drug carriers loaded with dexamethasone, a corticosteroid that is known to promote osteoinduction.

Formation of nano-phase hydroxyapatite film on TiO2 nano-network.

Nano- and micro-phase HA film formed on TiO2 nano-network surface by simple electrochemical treatment. The range of lateral pore size of the network specimen was about 10-120 nm on Ti surface by anodized in 5 M NaOH solution at 0.3 A for 10 min.

Corrosion behavior of nanotubular oxide on the Ti-29Nb-xZr alloy.

This work reports the corrosion behavior of nanotubular oxide layers on Ti-29Nb-xZr alloys with different compositions by anodization in 1 M H3PO4 + 0.8 wt% NaF. Depending on the alloy composition, nanoporous or highly ordered nanotube structures can be formed.

Antimicrobial effect of Korean propolis against the mutans streptococci isolated from Korean.

The aim of this study was to determine the optimal concentration of Korean propolis against clinical isolates of mutans streptococci (MS) from Koreans. The antimicrobial activity was evaluated using the minimum inhibitory concentration (MIC) and time-kill curves against mutans streptococci. The MIC(90) values of propolis for MS were 35 μg/ml.

Nanotube morphology and corrosion resistance of a low rigidity quaternary titanium alloy for biomedical applications.

Highly ordered nanotube oxide layers were developed on low rigidity quaternary beta-type Ti-35Nb-5Ta-7Zr alloy by controlled anodic oxidation in electrolyte containing 1 M H3PO4 and 0.5 wt% NaF at room temperature. The diameters of the nanotubes formed were in the range of 30 to 80 nm.

Cordyceps militaris induces the IL-18 expression via its promoter activation for IFN-gamma production.

Ethnopharmacological Relevance: Cordyceps militaris, one of traditional herbal ingredient in oriental medicine, has been known to promote anticancer and immunomodulatory activities in vitro and in vivo. However, the biological mechanism of anticancer activity has been unknown.

Objective: To investigate the effect of Cordyceps militaris extract on expression of interferon gamma (IFN-gamma) through interlukin-18 (IL-18) induction and its biological mechanism in vitro and in vivo.

Differential expression of system L amino acid transporters during wound healing process in the skin of young and old rats.

Unlabelled: In order to elucidate the role of the system L-type amino acid transporters (LATs) in the wound healing process of aged and young subjects, we investigated the expression of LAT1, LAT2 and their subunit 4F2hc in the skin healing process after artificial wounds of dorsal skin in the young and old rats.

Methods: The 1 cm full-thickness incisional wounds were made through the skin and panniculus carnosus muscle. The wounds were harvested at days 1, 3, 5 and 7 post-wounding, the experimental controls were harvested the skin of rat without wounds and the various analyses were performed.

Expression and functional characterization of the system L amino acid transporter in KB human oral epidermoid carcinoma cells.

We have examined the expression and function of system l amino acid transporter in KB human oral epidermoid carcinoma cells. The KB cells express l-type amino acid transporter 1 (LAT1) in plasma membrane, but not l-type amino acid transporter 2 (LAT2). The [14C]l-leucine uptake by KB cells is inhibited by system l selective inhibitor BCH.