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Objective:To investigate the effects of sodium arsenite (NaAsO 2) on the expression of sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator activated receptor α (PPARα) and fatty acid synthase (FAS) in human liver cells (L-02 cells). Methods:L-02 cells were cultured in vitro, and exposed to NaAsO 2 at 0 (control), 2, 4, 8, 16, 32, 64 and 128 μmol/L for 24 h, respectively, and the cell survival rate was determined by CCK-8 method. And a fitting curve was made to calculate the half inhibitory concentration (IC 50), subsequent experiments were carried out with 0, 1/8, 1/4 and 1/2 of IC 50 as arsenic exposure doses. Glycerol phosphate oxidase-catalase (GPO-PAP) method was used to detect the content of triglyceride (TG) in cells; the mRNA expression levels of SREBP-1c, PPARα and FAS were detected by Real-time PCR; and the protein expression levels of SREBP-1c and PPARα were detected by Western blotting. Results:The cell survival rates of 8, 16, 32, 64 and 128 μmol/L NaAsO 2 groups [(92.000 ± 1.414)%, (91.000 ± 0.000)%, (76.500 ± 0.707)%, (53.000 ± 1.412)%, (47.000 ± 1.412)%] were significantly lower than that of the control group [(100.000 ± 0.000)%, P < 0.01]. The IC 50 was 64 μmol/L, and subsequent experiments were conducted with 0 (control), 8, 16 and 32 μmol/L NaAsO 2, respectively. Compared with the control group [(1.000 ± 0.000) mmol/g prot], TG contents of 8, 16 and 32 μmol/L NaAsO 2 groups [(0.691 ± 0.064), (0.474 ± 0.162), (0.184 ± 0.045) mmol/g prot] were significant decreased ( P < 0.01). Compared with the control group, the mRNA expression levels of SREBP-1c, PPARα, FAS, and the protein expression levels of SREBP-1c and PPARα in NaAsO 2 groups were significantly decreased ( P < 0.01 or < 0.05). Correlation analysis showed that NaAsO 2 content was negatively correlated with TG content, SREBP-1c and PPARα protein expression levels ( r =-0.954,- 0.875,-0.965, P < 0.01). Conclusion:NaAsO 2 can reduce the TG content and the expression of lipid metabolism related genes SREBP-1c, PPARα and FAS in L-02 cells, suggesting that arsenic-induced liver injury can cause lipid metabolism disorders.
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Objective:To explore the role of nuclear factor-E2-related factor 2 (Nrf2) signaling pathway in oxidative damage caused by sodium arsenite (NaAsO 2) in human normal liver cells (L-02), and to provide experimental basis for the study of oxidative damage mechanism of liver damage caused by arsenic. Methods:L-02 cells were cultured in vitro and treated with 0 (control), 25, 50, 75, 100, 125, and 150 μmol/L NaAsO 2, respectively, for 24 h. The half-inhibitory concentration (IC 50) was calculated according to the cell survival rate by CCK8, and L-02 cells were treated with 0, 1/8, 1/4 and 1/2 dose of IC 50 of NaAsO 2, respectively, for grouping experiments. Protein expressions of Nrf2, heme oxygenase-1 (HO-1), NADH quinone oxidoreductase 1 (NQO1) and glutathione peroxidase 1 (GPx1) in L-02 cells and L-02 nucleus were detected by Western blotting. Results:The result of CCK8 showed that the survival rates of L-02 cells in 25, 50, 75, 100, 125, 150 μmol/L NaAsO 2 groups were [(69.53 ± 0.06)%, (41.33 ± 0.08)%, (23.65 ± 0.04)%, (26.51 ± 0.04)%, (31.63 ± 0.01)%, (26.24 ± 0.02)%], which were significantly lower than that of the control group[(100 ± 0.00)%]. The differences were statistically significant ( P < 0.05). The IC 50 calculated by cell survival was 40 μmol/L, and the NaAsO 2 doses used in the experiment were 0 (control), 5, 10, and 20 μmol/L. Western blotting results showed that, compared with the control group, the protein expression levels of Nrf2, HO-1 in L-02 and HO-1 in the L-02 cells nucleus in the 5, 10 and 20 μmol/L NaAsO 2 groups were significantly higher ( P < 0.05). Compared with the control group, the expression levels of GPx1 protein in L-02 cells of 10 and 20 μmol/L NaAsO 2 groups were decreased ( P < 0.05). Compared with the control group, the expression levels of Nrf2 protein in L-02 nucleus in 10 and 20 μmol/L NaAsO 2 groups were significantly increased ( P < 0.05); the expression level of NQO1 protein in L-02 nucleus in 5 μmol/L NaAsO 2 group was significantly increased ( P < 0.05). Conclusion:NaAsO 2 has an effect on the expression of Nrf2 signaling pathway related factors in L-02 cells, and the mechanism of oxidative damage caused by NaAsO 2 in L-02 cells may be related to Nrf2 signaling pathway.
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Objective:To explore the mechanism of apoptosis induced by sodium arsenite (NaAsO 2) in human hepatic cells (L-02) through reactive oxygen species (ROS) accumulation and mitochondrial dysfunction, and provide experimental evidence for the mechanism of arsenic poisoning. Methods:L-02 cells were divided into control group, NaAsO 2 group (10 μmol/L NaAsO 2), N-acetylcysteine (NAC) group (5 mmol/L NAC), and NaAsO 2 + NAC group (10 μmol/L NaAsO 2, 5 mmol/L NAC), and were cultured in vitro for 24 h. The intracellular ROS level, mitochondrial membrane potential depolarization ratio and cell apoptosis rate were measured by dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescence probe, JC-1 staining and Annexin V-FITC/PI double staining, respectively; the mRNA and the protein of Caspase 3, cytochrome C (Cyt-C) and cytochrome C oxidaseⅣ (COXⅣ) were detected by real time fluorescence quantitative PCR (qRT-PCR) and Western blotting, respectively. Results:There were statistically significant differences in intracellular ROS levels (3 857 392.33 ± 44 928.39, 4 515 288.00 ± 32 660.64, 3 670 150.67 ± 101 987.69, 4 035 235.67 ± 99 995.30), mitochondrial membrane potential depolarization ratios (2.16 ± 0.54, 7.95 ± 0.52, 2.70 ± 0.29, 1.01 ± 0.23) and total apoptosis rates (1.45 ± 0.03, 4.27 ± 0.17, 1.87 ± 0.12, 2.52 ± 0.35) between groups ( F = 62.62, 159.81, 112.70, P < 0.05). There were statistically significant differences in Caspase 3, Cyt-C, COXⅣ mRNA expression levels ( F = 9.20, 7.33, 14.87, P < 0.05) and in cleaved-Caspase 3, Cyt-C, COXⅣ protein expression levels( F = 31.42, 8.01, 83.30, P < 0.05) between groups. Compared with the control group, the intracellular ROS level, mitochondrial membrane potential depolarization ratio and total apoptosis rate were significantly increased ( P < 0.05); Caspase3, Cyt-C mRNA and protein expression levels were significantly increased ( P < 0.05), and COXⅣ mRNA and cleaved-Caspase 3, Cyt-C protein expression levels were significantly decreased ( P < 0.05) in NaAsO 2 group. Compared with the NaAsO 2 group, the intracellular ROS level, mitochondrial membrane potential depolarization ratio and total apoptosis rate of NaAsO 2 + NAC group were significantly decreased ( P < 0.05); the Caspase3, Cyt-C mRNA and cleaved-Caspase 3, Cyt-C protein expression levels were significantly decreased ( P < 0.05), the COX Ⅳ mRNA and protein expression levels were significantly increased ( P < 0.05). Conclusions:NaAsO 2 stimulates L-02 cells to produce excessive ROS, which induces mitochondrial depolarization and further triggers mitochondrial damage, resulting in increased release of Cyt-C and activation of the mitochondrial apoptosis pathway that Caspase 3 protein induces apoptosis in L-02 cells, which may be one of the main mechanisms of arsenic-induced liver injury.
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Objective To investigate the effects of three mitogen-activated protein kinase (MAPK) inhibitors on the expressions of transforming growth factor-β1 (TGF-β1),α-smooth actin (α-SMA) mRNA and protein in human liver stellate cells (LX-2 cells) activated by sodium arsenite.Methods Cultured in vitro LX-2 cells in the logarithmic growth stage were exposed to sodium arsenite at 0.0 (control),2.5,5.0,10.0,20.0,40.0,80.0 μmol/L for 24 h,respectively,and the cell survival rate was determined by CCK-8 assay.According to the results of the study,LX-2 cells were divided into 5 groups:control group,sodium arsenite group,extracellular signal regulation kinase (ERK) inhibition group,c-Jun amino-terminal kinase (JNK) inhibition group,and p38 inhibition group.LX-2 cells were pre-treated with 10.0 μmol/L ERK,JNK,p38 kinase inhibitors (PD98059,SP600125,SB203580) for 30 min in the 3 inhibition groups,and then 20.0 μmol/L sodium arsenite for 24 h.The control group was not treated with sodium arsenite and inhibitors.Sodium arsenite group was not treated with inhibitors.Then mRNA and protein expression levels of TGF-β1 and α-SMA in LX-2 cells were determined by Western blotting and real-time PCR,respectively.Results The survival rates of LX-2 cells in 5.0,10.0,20.0,40.0,80.0 μmol/L sodium arsenite groups were [(92.35 ± 0.92)％,(84.06 ± 0.84)％,(74.27 ± 0.74)％,(59.57 ± 0.60)％,(27.77 ± 0.23)％],which were significantly lower than that of the control group [(100.00 ± 0.00)％,P ＜ 0.05].It was found that the expressions of TGF-β1,o-SMA mRNA and protein of sodium arsenite group were higher than those of the control group (P ＜ 0.01).The expressions of TGF-β1,α-SMA mRNA and protein of the three inhibition groups were lower than those of the sodium arsenite group (P ＜ 0.05).Conclusions Arsenic exposure can cause abnormally high expressions of TGF-β1,α-SMA mRNA and protein in LX-2 cells.Intervention with three MAPK inhibitors can improve the effects of arsenic induced LX-2 cells activation on the expressions of TGF-β1,α-SMA mRNA and protein.
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Glioma is one of the most common intracranial tumors.Long non-coding RNA(lncRNA) cannot be translated into proteins but has many important effects on bio-functions and diseases of human beings.The functions of lncRNA includes epigenetic regulation,transcription regulation,lncRNA-miRNA interation,being precursor of miRNA and these functions play important role in pathogenesis of glioma,lncRNA has many regulatory effects on the proliferation,invasion and metastasis of glioma cells,and plays a guiding role in the diagnosis and treatment of glioma.lncRNA influence the proliferation,migration and invasion of glioma and the study of lncRNA mean a lot in the treatment of patients with glioma.
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Objective To observe the clinical effects of transmission straight wire appliance on the treatment of AngleⅡ1 malocclusion and explore its mechanism.Methods Thirteen AngleⅡ1 malocclusion patients (6 males and 7 females) were treated with the appliance by extracting 4 first premolars or 2 first maxillary premolars.The results of cephalometric measurements before and after treatment were statistically analyzed.Results The average treatment time of 13 cases was 15.6 months.The overbite's treatment cost 4.2 months averagely.Overbite,overjet and molar relationship were turned to normal (only one adult case had complete distal in the molar relationship by extracting 2 first maxillary premolar) and lateral appearances were improved after treatment.The results of cephalometric analysis showed that the changes of SNB,ANB,U1-NA angle,L1-NB angle,U1-LI angle,U1-NA length,L1-NB length,L6-MP length,L1C-MP length,overbite,and overjet were of high statistical significance (P0.05).Conclusion Transmission straight wire appliance can quickly and efficiently correct AngleⅡ1 malocclusion.
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Objective:To study the related factors of landmarks identification repeatability in the computer monitoring. Methods:Totally 30 lateral cephalograms were selected at random, and the landmarks were identified by 2 orthodontists with the computer monitor twice. The data were obtained and the differences were analyzed. Results:There were differences in inter-operator and intra-operator in their coordination. The operators were similar to each other within a certain range. There were significant differences between the data of the abscissas and ordinate in some landmarks. Conclusion:The repeatability of identified landmarks is closely related to the location of the landmarks, the landmarks identification by human eyes and the quality of the X-rays.
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0.05).Conclusion:The computer can reach the accurate degree while marking one by hand.
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Objective:The purpose of this study was to obtain the normal value of McNamara analysis for Chongqing adolescents with normal occlusion of permanent dentition.Methods:Chongqing adolescents with normal occlusion were taken 55 lateral cephalograms.McNamara analysis was conducted and the obtained data were compared with that of Chengdu,Shanghai and McNamara,respectively.Results:There was significant difference in the normal values of McNamara analysis between male and female Chongqing adolescents by t test;there was significant difference between Chongqing and Chengdu,Chongqing and Shanghai,Chongqing and McNamara also.Conclusion:There is significant difference in values of normal occlusion of McNamara analysis in different regions and different races.
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Objective:To establish the normal value of McNamara cephalometric analysis in Chongqing adolescents with normal occlusion and to obtain its regression models. Methods:Fifty five Chongqing adolescents with normal occlusion (male 27 and female 28)were taken lateral cephalograms. McNamara analysis was conducted and the correlation analysis was carried out.Results: There were significant differences in the normal values of McNamara analysis between male and female Chongqing adolescents, namely the effective maxillary length, effective mandibular length, lower anterior facial height and A Np line. There were no significant differences in Pog Np line, upper incisor to point A vertical,lower incisor to A P line.There were correlations between the effective maxillary length and effective mandibular length, effective mandibular length and lower anterior facial height, A Np line and Pog Np line, respectively.When effective mandibular length was fixed,lower anterior facial height and Pog Np line was correlated.The regression models were obtained.Conclusion:There is correlation between the linear measurements of the cephalometrics values.