Effects of ultrasound on osteotomy healing in a rabbit fracture model.

This study investigated the effects of ultrasound (US) at different frequencies on fracture healing over a three-week period in a rabbit fibular fracture model. Forty-five adult New Zealand White rabbits were divided into five groups: a control group and four groups treated with US frequencies of 0.5, 1.

Tracking of cellular uptake of hydrophilic CdSe/ZnS quantum dots/hydroxyapatite composites nanoparticles in MC3T3-E1 osteoblast cells.

We report the fluorescent labeling of osteoblast cells using the biocompatible hydroxyapatite (HA) grown with nucleating seed of hydrophilic CdSe/ZnS quantum dots (QDs) allowing the real-time observation of cell under confocal microscope. We found that the MC3T3-E1 osteoblast cells can engulf HA with surface-tailored QDs showing fluorescent spots in the cytoplasm, while HA and QDs nanoparticles were not engulfed. It is interesting to see that the fluorescence was only displayed in the cytoplasm of MC3T3-E1 osteoblast cells.

Cytokine release from osteoblasts in response to different intensities of pulsed electromagnetic field stimulation.

We use an in-vitro osteoblast cell culture model to investigate the effects of low-frequency (7.5 Hz) pulsed electromagnetic field (PEMF) stimulation on osteoblast population, cytokines (prostaglandin E(2) (PGE(2)), transforming growth factor beta1(TGFbeta1), and alkaline phosphatase (ALP) activity to find the optimal intensity of PEMF for osteoblast growth. The results demonstrate that PEMF can stimulate osteoblast growth, release of TGFbeta1, and, in addition, an increase of ALP activity.

Comparison of ultrasound and electromagnetic field effects on osteoblast growth.

This study compares the mechanisms of ultrasound (US) on osteoblast proliferation with those of pulsed electromagnetic field (PEMF), by different signal transduction pathway inhibitors. The cells were stimulated for 15 min under US or for 2 h under PEMF exposure. Twenty-four h after the beginning of stimulation, the cells were harvested and used for mitochondrial activity test (MTT) analysis.