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Objective:To investigate the stiffness characteristic of triple-negative human breast cancer at different size in a implantation nude female mice model using shear wave elastography(SWE) and to compare the clinical pathologic features of tumors with elasticity variables.Methods:Human breast cancer MDA-MB-231 cells were injected into 30 nude female mice and 27 transplanted tumors were successfully found in nude female mice. Ultrasound and SWE were longitudinally performed on maximum diameter plane of 21 tumours in 21 nude mice. The elastic parameters of maximal elasticity(Emax), mean elasticity (Emean) and standard deviation of elasticity(Esd) were recorded. The mice were divided into 3 groups according to the tumor size. They were group A with tumor size less than or equal to 5 mm, group B with tumor size greater than 5 mm and less than or equal to 10 mm, group C with tumor size larger than 10 mm and smaller than or equal to 15 mm. Compared with pathology, the relationships between Ki67 of transplanted tumor and elastic parameters were analyzed.Results:As the transplanted tumors increased, the values of Emax, Esd, Ki67 all increased. The lesions maximal size, Emax, Esd, Ki67 were significant higher in group B ( P<0.001, P=0.006, P=0.002, P=0.026) and group C ( P<0.001, P<0.001, P<0.001, P=0.028) than group A. The other parameters were not significantly different among the groups(all P>0.05). The size of transplanted tumors was significantly and positively correlated with Emax ( rs=0.673, P=0.001), Esd ( rs=0.661, P=0.001), and Ki67 ( rs=0.509, P=0.018). Conclusions:SWE Emax and Esd can reflect the tumor tissue stiffness change and biological activity during the tumor growth.
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Objective To explore the effect of an electromagnetic field (EMF) on the viability,proliferation and osteogenic differentiation of rats' bone mesenchymal stem cells (rBMSC).Methods Sinusoidal 1mT EMFs of 10 Hz,30 Hz,50 Hz and 70 Hz were administered to rBMSC for 2 hours per day during 2 weeks of cultivation.The cell viability was analyzed using live/dead assays.The cells' DNA was quantified to evaluate cell proliferation.Von Kossa staining was performed to study the mineralization of the extracellular matrix.The enzyme linked immunosorbent assay (ELISA) and immunohistological staining were employed to observe the synthesis of osteocalcin (OC) and bone morphogenetic protein-2 (BMP-2).Results Cell viability decreased under exposure to the 50 Hz and 70 Hz fields.The proliferation of rBMSC was elevated significantly in the 10 Hz EMF-treated group.The expression OC and BMP-2 was elevated after two weeks of 50 Hz EMF stimulation.Moreover,the mineralization of the extracellular matrix was found to be enhanced after 50 Hz EMF exposure.Conclusion Exposure to a 1 mT EMF has different effects on the viability,proliferation and osteogenic differentiation of rBMSC depending on the frequency.The data provide practical guidance for applying electromagnetic fields in bone regenerative medicine.
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Colorectal cancer is one of the most common malignant tumors of digestive system.There are significant differences between young patients and other ages in aspects of the disease features, biological characteristics, risk factors, clinical treatment and prognosis, etc.And the analysis of young colorectal cancer patients′ characteristics can provide new ideas for clinical treatment.
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Objective To study the effects of pulsed electromagnetic field (PEMF) in promoting tibia and fibula fracture healing in rats. Methods Thirty rats were divided randomly into two groups after establishing the animal model of artificial tibia and fibula fracture: a PEMF treated group and a control group. Radiographs were taken immediately postoperatively and once a week thereafter until being sacrificed after week 5. The blood was sampled to measure the activity of alkaline phosphatase (ALP) and the concentration of bone gamma-carboxyglutamic-acid-con-taining proteins (BGP), calcium and phosphate in serum once a week, respectively. Histological sections were taken at weeks 3 and 5 to observe the pathological change of bony callus. Results PEMF of 15 Hz and 1.0 mT could sig-nificantly increase the amount of bony callus, significantly increase the amount of bony callus, promote the disappea-ring of fracture lines and the appearance of endochondral ossification and mature bone trabecula. The amount of colla-gen in bony callus raised and the process of callus moulding accelerated in PEMF treated group. In addition, the ac-tivity of ALP(P<0.04) and the concentration of BGP(P<0.05) in serum increased. Conclusions The PEMF of 15 Hz and 1.0 mT can obviously promote fracture healing of tibia and fibula in rats.
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Objective To study the effects of an electromagnetic field (EMF) on the expression of fibro-blast growth factor (FGF-2) and it' s receptor (FGFR-2) mRNA in rat bone marrow mesenchymal stem cells (BMSCs) in vitro. Methods Rat BMSCs were isolated and cultured in vitro. The subcultured cells were divided into different groups to be EMF stimulated at 1.0 mT. The expression of FGF-2 and FGFR-2 mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR). Results Different frequencies and durations of 1.0 mT EMF exposure induced FGF-2 and FGFR-2 mRNA expression in comparison to blank controls. The expression of FGF-2 mRNA reached a peak after stimulation at 15 Hz for 10 min, 50 Hz for 60 min and 75 Hz for 30 min. And the expression of FGFR-2 mRNA reached a peak after 30 minutes at all frequencies. At 1.0 mT with 30 min exposure, the expression of FGF-2 mRNA peaked after 50 Hz stimulation, and the expression of FGFR-2 mRNA peaked after stimulation at 75 Hz. Conclusions Moderate EMF stimulation can significantly increase the expression of FGF-2 and FGFR-2 mRNA in rat BMSCs in vitro.
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Objective To study the effects of electromagnetic field (EMF) exposure on osteoporosis in ovariectomized mice. Methods Sixty 8-week-old female Kunming mice were divided into four groups at random: a sham operation group (group A), an ovariectomized group (group B), an EMF and ovariectomized group (group C) and a nilestriol and ovariectomized group (group D). Bilateral ovariectomies were performed on all mice except those in group A. The mice of group C were exposured to a 15 Hz, 1.0 mT electromagnetic field. The mice of group D were given at nilestriol 1.5 mg/kg/week. The bone mineral density (BMD) of the lumbar vertebrae was measured before the mice were sacrificed at the 12th week. Blood specimens were collected every two weeks to measure the ac-tivity of alkaline phosphatase (ALP) and the concentration of bone gamma-carboxyglutamic-acid-containing proteins (BGP), calcium and estradiol in the serum. Histological sections were taken to examine and analyze the changes in bone trabeculae in the lumbar vertebrae after 6 and 12 weeks. Results EMF at 15 Hz and 1.0 mT intensity signifi-cantly increased the activity of ALP and the concentrations of BGP and calcium in the serum. In addition, the absorp-tion of bone trabeculae in the lumbar vertebrae was significantly restrained. Conclusions EMF at 15 Hz and 1.0 mT can restrain the development of osteoporosis in ovariectomized mice.