Tu Y.,Fourth Military Medical University |
Gao X.,Fourth Military Medical University |
Gao X.,Xian Medical University |
Gao X.,Shanghai Institute of Technology |
And 7 more authors.
Cancer Research | Year: 2013
Malignant gliomas are the most common central nervous system tumors and the molecular mechanism driving their development and recurrence is still largely unknown, limiting the treatment of this disease. Here, we show that restoring the expression of miR-218, a microRNA commonly downregulated in glioma, dramatically reduces the migration, invasion, and proliferation of glioma cells. Quantitative reverse transcription PCR and Western blotting analysis revealed that expression of the stem cell-promoting oncogene Bmi1 was decreased after overexpression of miR-218 in glioma cells. Mechanistic investigations defined Bmi1 as a functional downstream target of miR-218 through which miR-218 ablated cell migration and proliferation. We documented that miR-218 also blocked the self-renewal of glioma stem-like cells, consistent with the suggested role of Bmi1 in stem cell growth. Finally, we showed that miR-218 regulated a broad range of genes involved in glioma cell development, including Wnt pathways that suppress glioma cell stem-like qualities. Taken together, our findings reveal miR-218 as a tumor suppressor that prevents migration, invasion, proliferation, and stemlike qualities in glioma cells. © 2013 American Association for Cancer Research.
Jia D.,PLA Fourth Military Medical University |
Han B.,Xian Medical University |
Yang S.,First Peoples Hospital of Xianyang |
Zhao J.,Xian Medical University
Journal of Molecular Neuroscience | Year: 2014
In the present study, we aimed at evaluating the potential neuroprotective effect and the underlying mechanism of anemonin against cerebral ischemia and reperfusion (I/R) injury. Anemonin was administered to rats by the intraperitoneally (i.p.) route once daily for 7 days before middle cerebral artery occlusion (MCAO). Focal cerebral ischemia was induced by 90 min of MCAO followed by 24 h of reperfusion. After that, animals were sacrificed by decapitation, brain was removed, and various biochemical estimations, neurological status, and assessment of cerebral infarct size were carried out. MCAO followed by 24 h of reperfusion caused a significant increase in infarct size, neurological deficit score, malondialdehyde (MDA) content, reactive oxygen species (ROS) level, and DNA fragmentation, as well as a decrease in the activities of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx), and Na+, K+-ATPase in the brain. Furthermore, elevated Bax expression, increased caspase-3 cleavage, and decreased Bcl-2 expression were observed in nontreated rats in response to focal cerebral I/R injury. However, pretreatment with anemonin significantly reversed these levels of biochemical parameters, reduced cerebral infarct size, and improved the neurologic score in cerebral ischemic animals. Additionally, a wide distribution of anemonin in plasma and brain tissues and the brain-to-plasma partition coefficient (Ri) ratio of 0.7 at 90 min indicated that this compound could penetrate the blood-brain barrier (BBB). These results showed that pretreatment with anemonin provided a significant protection against cerebral I/R injury in rats by, at least in part, its antioxidant action and consequent inhibition of apoptosis. © 2014 Springer Science+Business Media.
Xu T.,Xian Medical University
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology | Year: 2013
To investigate the combined effects of insulin and selenium in improving the physiological parameters and insulin signal transduction in the skeletal muscles of diabetic rats. 35 male SD rats were randomly divided into five groups: normal, diabetes, diabetes with insulin treatment (D-In group), diabetes with sodium selenite treatment (D-In-S group), and diabetes with insulin and sodium combination treatment (D-In-Se group), 7 rats in each group. The levels of blood glucose were measured using One Touch Sure Step Blood Glucose Meter. HbA1C levels were measured using microcolumn assay. The levels of insulin receptor substrate 1(IRS-1), phosphatidylinositol-3 kinase (PI3K) and glucose transporter 4(GLUT4) in skeletal muscle were examined by Western blotting and immunohistochemistry. Insulin combined with selenium could significantly lower blood glucose levels and markedly restore the diminished expression of in IRS-1, PI3K and GLUT4 levels in skeletal muscles of diabetic rats. There was positive cooperativity between insulin and selenium in reducing blood glucose levels in diabetic rats. The combined treatment of insulin and selenium may decrease blood glucose by upregulating IRS-1, PI3K and GLUT4 levels in skeletal muscles of diabetic rats.
Cao P.H.,Xian Medical University
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology | Year: 2010
AIM: To investigate the effect of Nivalenol(NIV) and Selenium(Se) on the levels of IL-1beta and TNF-alpha in the cultured chondrocytes. METHODS: Human chondrocytes cultured in vitro were treated with or without NIV and Se. The morphology of chondrocytes was observed by optic microscope. The DNA content was determined by UV Spectrophotometry. The levels of IL-1beta and TNF-alpha in cultured medium were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Hematoxylin & eosin staining indicated there was cell necrosis in the cartilage reconstructed in vitro from both NIV group and NIV+Se group. Compared with the group of NIV toxin, the damage of chondrocytes was less severe when Se was added. NIV could inhibit chondrocyte DNA synthesis. The content of DNA with NIV was lowest than that in other groups. The levels of IL-1beta and TNF-alpha with NIV were significantly higher than control group (P<0.05). After Se was added, the levels did not change significantly compared with the groups without Se. CONCLUSION: NIV toxin could superinduce IL-1beta and TNF-alpha secretion in chondrocytes, which may be the key mechanism of chondrocyte injury by NIV. Se can partially alleviate the effects of NIV on chondrocytes cultured in vitro.
Zeng J.R.,Xian Medical University
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology | Year: 2012
To observe the expression changes of tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) during the developing process of pressure overload-induced myocardial remodeling in rats, and investigate the dynamic correlation between TNF-α and left ventricular mass index (LVMI) as well as myocardial collagen volume fraction (CVF). The rats (n=56) were randomly divided into control group, sham operation group and model group. Animal models were induced by abdominal aortic constriction (AAC). AAC group was further divided into 2 weeks, 4 weeks, 8 weeks and 12 weeks groups. Dynamic expression changes of TNF-α and IL-10 were tested by enzyme-linked immunosorbent assay(ELISA), and myocardial collagen fiber was observed by Mallory's staining. Myocardial cells became increasingly disarranged, filaments broken, intercellular space increased, and collagen fiber accumulated 4 weeks after operation. Furthermore, heart failure occurred 12 weeks after operation. ABC-ELISA results showed that TNF-α expression in myocardium increased at 4, 8, 12-week operation groups in a time-dependent fashion compared with control group (P<0.01); Correlation analysis indicated the expression of TNF-α in myocardium was positively correlated with LVMI (r=0.582, P<0.01) and CVF (r=0.932, P<0.01); IL-10 expression in myocardium among groups were similar, but the ratio of TNF-α and IL-10 increased in a time-dependent manner, from (1.79 ± 0.19) ng/mL (2 weeks) up to (2.85 ± 0.24) ng/mL(12 weeks) as compared with control group (1.74 ± 0.24) ng/mL (P<0.01). The degree of myocardial remodeling plays a key role in heart function deterioration, and the TNF-α expression up-regulation in a time-dependent manner and the disproportion of TNF-α and IL-10 is one of important molecular mechanisms.
Yang H.Y.,Xian Medical University
Advanced Materials Research | Year: 2014
Electrocardiosignal feature extraction is the base of electrocard iologic automatic diagnosis. By using wavelet transform multi-resolution analysis, the noise in electrocard iosignal is removed; and by using proximity signals of wavelet transform the base linew ander is filtered. The high frequency noise is handled and eliminated with the default threshold; and the average value of the electrocardiosignals is set to zero. In detection of rpeak, because leak detection will occur when only 23 detail signals is considered, thus the 23 and 24 detail signals are integrated to avoid miss detection effectively. The methods avoiding error detection bring excellent effects. For calculating average cardiac electric axis, among the methods of area method, time voltage method and amplitude method, the area method offers the highest accuracy. © (2014) Trans Tech Publications, Switzerland.
Nan F.,Xian Medical University
International Journal of Control and Automation | Year: 2016
With the features of high density, speed and too many restrictions, train operation adjustment on double track-line is a typical large-scale combinatorial optimization problem and the NP-hard problem. In this paper, based on the characteristics of China's railway operation, a mathematical model is built to shorten the train group's total delayed time and reduce the delayed time to the minimum, and which is solved and optimized with differential evolution algorithm. As the standard differential evolution algorithm can easily lead to the problem of 'premature convergence', an improved differential evolution algorithm is put forward. In the improved algorithm, the adaptive nonlinear regressive mutation operator and crossover operator of t-distribution are adapted to improve the mutation and the design of crossover operator in the standard differential evolution algorithm. The experimental results show the improved differential evolution algorithm has a high rationality and feasibility in solving the problem of train operation adjustment on double track-line, and it has better results than applying the genetic algorithm and standard differential evolution algorithm. © 2016 SERSC.
Huo J.,Xian Medical University
Artificial Cells, Nanomedicine and Biotechnology | Year: 2016
To observe the changes in invasion capacity of gastric cancer BGC823 cells after being treated with chitosan-encapsulated BRAF siRNA nanoparticles, and to evaluate the effects of the nanoparticle-mediated BRAF siRNA interference on cell invasion and metastasis, BRAF siRNA was encapsulated with chitosan into nanoparticles sized 350 nm to treat gastric cancer cells. Silencing of BRAF was detected by Western blot and PCR, and cell invasion was observed by the Transwell assay. The nanoparticles significantly downregulated BRAF expression in BGC823 cells (P < 0.01) and inhibited their invasion (P < 0.001). Chitosan nanoparticle-mediated BRAF siRNA interference evidently reduced the invasion capacity of gastric cancers. © 2015 Informa Healthcare USA, Inc.
Bei Q.,Xian Medical University
Jiegou Huaxue | Year: 2012
A new asymmetric bidentate copper(II) complex, CuL2 (HL = 2-((E)-(4-bromophenylimino) methyl)-6-bromo-4-chlorophenol), has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space group P2 1/c with a = 11.218(3), b = 9.355(3), c = 13.449(4) Å, β = 108.722(4)°, V = 1336.8(6) Å 3, Z = 2, D c = 2.008 g/cm 3, μ(MoKa) = 7.024 mm -1, F(000) = 806, S = 0.999, the final R = 0.0342 and wR = 0.0641 for 2611 observed reflections (I > 2s(I)). The central copper(II) is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands. The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions. In addition, DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements. The results show that the complex binds with calf-thymus DNA(CT-DNA), presumably via a partial intercalative mode. The intrinsic binding constant of the Cu(II) complex with DNA is 7.335×10 3 M -1. Copyright © 2008 Chinese Journal of Structural Chemistry.
Pan X.-W.,Xian Medical University
Fangzhi Gaoxiao Jichukexue Xuebao | Year: 2012
For any positive integer n, let φ(n) and S(n) denote the Euler function and the Smarandache function respectively. For a fixed positive integer k,if x is a positive integer satisfying x>1 and φ(x) = S (xk), then x is called a non-trivial solution of the equation φ(x) = S(xk). Using some elementary number theory methods, it is proved that ( ¡) All non-trivial solutions x of φ(x) = S(xk) satisfy 2k