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Objective To study the diagnostic value of magnetic resonance imaging (MRI) and spiral CT in thyroid microcarcinoma (TMC), in order to improve the diagnostic accuracy of TMC. Methods The preoperative imaging manifestations of MRI and spiral CT in 68 TMC patients who were confirmed by surgical pathology were retrospectively analyzed, and the diagnostic accordance rates were compared between the independent and the combined diagnosis. Results The diagnostic accordance rates of MRI and spiral CT in TMC were 73.53%(50/68) and 66.18%(45/68). The diagnostic accordance of combined MRI and spiral CT in TMC was 88.24%(60/68). The diagnostic accordance rate of combined MRI and spiral CT was significantly higher than that of independent examine, and there was statistical difference (P0.05). Conclusions Spiral CT is superior to MRI in the micro-calcification detection, and MRI, with a high resolution of soft tissue, can display the lesions of surrounding tissue organs and neck lymph node metastasis better. The combined examine can increase the diagnostic accuracy of TMC.
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Objective To investigate the effects of silencing of the human cerebral 21 .5 kDa myelin basic protein (MBP) gene on the proliferation and apoptosis of the glioma U251 cells .Methods The 21 .5 kDa MBP sequence‐specific short hair‐pin RNA (shR‐NA) recombinant plasmids pGenesil‐1‐MBP‐3 were transfected into the human glioma cell line(U251) ,the cells of U251 was used as MBP silencing group ,the cells transfected with negative control plasmids used as negative control group ,and the cells transfected with liposomes used as blank control group .Real‐time PCR and Westernblot were used to detect the expression levels of the 21 .5 kDa MBP mRNA and protein in each group ,and the cell proliferation curve was measured by CCK‐8 assay ,the apoptosis rate was a‐nalysised by Flow cytometry .Results Both the mRNA and the protein expression levels of the 21 .5 kDa MBP of MBP silencing group were significantly lower than those in the control groups (P<0 .05);the cellular proliferation activity of the MBP silencing group decreased significantly (P<0 .05)while the cellular apoptotic rate increased significantly (P<0 .05) .Conclusion Silencing of the human cerebral 21 .5 kDa MBP gene may playa dual role in the inhibition of proliferation and the promotion of apoptosis of the glioma U251 cells .
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Objective To investigate the different radioprotective effects of total flavonoids of Astragalus (TFA) on human normal mesenchymal stem cells(hMSCs) and hepatoma cells injured by 60 Coγ-ray radiation.Methods hMSCs and HepG-2 cells were cultured and randomly divided into TFA-treated and untreated groups.The cells of different groups were irradiated with 60 Co γ-rays at the dose of 6 Gy.MTT method was utilized to detect the survival rates of the hMSCs and HepG-2 cells pretreated or untreated with TFA before irradiation.Cell clone formation test was used to measure the cellular radiosensitivity.The apoptosis rates of different groups were determined by flow cytometer assay.The expression rates of the apoptosis-promoting proteins Fas and Bax and the apoptosis-inhibiting protein Bcl-2 were analyzed by Western blotting.Results MTT showed that the survival rates of hMSCs pretreated by TFA were 1.15-1.95 times higher than that of the pure irradiation group.On the contrary,the survival rates of the TFA pretreated HepG-2 cells were only 0.53-0.23 times that of the pure irradiation group.There was a good dose-effect relationship between the cell survival rate and the TFA concentration.Cell clone formation rate indicated that combined treatment of TFA and radiation inhibited the cell proliferation more effectively than single TFA or pure radiation.Flow cytometry showed that 6,24 and,48 h post-irradiation to 6 Gy,the apoptosis rates of the hMSCs were 23.3% ,11.2% ,and 2.9% ,respectively in the TFA pretreated group and were 29.3% ,24.9% ,and 13.6% in the pure radiation group.However,the apoptosis rates of the HepG-2 cells at 6,24,and 48 h post-irradiation to 6 Gy were 11.6% ,17.3% ,and 20.1% ,respectively in the TFA pretreated group and were 6.9% ,9.3% ,and 15.8% ,respectively in the direct radiation group.Western blotting showed that the expression levels of Fas and Bax proteins in the HepG-2 cells were significantly higher in the TFA pretreated group than in the pure radiation group.On the contrary,the expression level of the apoptosis inhibiting protein Bcl-2 was significantly lower in the TFA pretreated group than in the pure radiation group.Conclusions TFA has obvious effects of radiological protection on human hMSCs and has no effects of radiological protection but effects of apoptosis enhancement on hepatoma cells.The promotion of apoptosis of TFA on hepatoma cells is primarily through increasing the expression of apoptotic proteins such as Fas and Bax and reducing the expression of anti-apoptotic protein Bcl-2.