Positron emission tomography (PET) can provide functional images and identify abnormal metabolic regions of the whole-body to effectively detect tumor presence and distribution. The filtered back-projection (FBP) algorithm is one of the most common images reconstruction methods. However, it will generate strike artifacts on the reconstructed image and affect the clinical diagnosis of lesions.
View Article and Find Full Text PDFThis study was performed to investigate osteoblastogenesis of human mesenchymal stem cells (hMSCs) cultured in 3-D scaffolds stimulated with low-intensity pulsed ultrasound and to identify the underlying mechanism mediated by soluble receptor activator of nuclear factor kappa B ligand (sRANKL) secreted by hMSCs. The results indicate that the mRNA levels of core-binding factor subunit alpha subunit 1 (CBFA1), osterix (OSX), alkaline phosphatase (ALP), osteocalcin and osteoprotegerin (OPG) and sRANKL production of hMSCs stimulated by ultrasound were significantly increased compared with the levels without ultrasound stimulation. Attenuating the sRANKL activity of ultrasound-treated hMSCs significantly reduced the mRNA expression of CBFA1, OSX, ALP and OPG.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
March 2008
Previous studies have shown that Amyloid-beta (A beta) may induce the apoptosis of neuronal cells leading to the syndrome of Alzheimer's disease (AD). The stimulation by optical energy was found able to greatly inhibit A beta induced apoptosis. This study aims to further explore the effect of different doses of ultrasonic insonification on neuronal cells.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
March 2008
Previous studies have indicated that low intensity ultrasounds could accelerate the repair of fibula fracture and facilitate the proliferation of osteoblasts. To further investigate the effect of low intensity ultrasounds, two different frequency of ultrasound, 1 MHz and 3 MHz, were applied to osteoblasts. The cells were stimulated for a typical 20% duty cycle of ultrasound with various intensities ranged from 50 to 150 mW/cm2 (ISATA) for 3 minutes once daily for 6 days.
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