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Objective: To investigate the effect of moderate-intensity aerobic exercise on the differential expression of rat atrial muscle Proteomics and genes, which provide research basis for the rehabilitation of chronic cardiovascular diseases and exercise -induced cardiac remodeling research., Methods: Twenty male SD rats were randomly divided into control group and experimental group ( n =10) according to body weight. Rats in the experimental group were trained (6 days per week),which lasted for 4 weeks of moderate-intensity aerobic exercise at a rate of 24 m·min -1 for 40 min (load intensity equivalent to 60%~70% VO 2max ). The proteins were separated by two dimensional gel electrophoresis, and the tandem time-of- flight mass spectrometer technique was used to identify 13 candidate target protein spots. The expression levels of these 13 protein spots were up-regulated more than 5 times or down -regulated to below 1/5. The mRNA of six target proteins were detected by reverse transcription-polymerase chain reaction (RT-PCR)., Results: By software analysis, the experimental group compared with the control group, there were 8 protein points which their expression reduced more than 4/5 and 5 protein points up-regulated more than 5 times, 13 proteins were identified by mass spectrometry protein spots, the final identification results acquired 8 proteins and a unknown protein of molecular mass 54 KDa, such as:pyruvate dehydrogenase E1α1, mitochondrial aconitate hydratase, protein disulfide isomerase A3, methylmalonic acid semialdehyde dehydrogenase, mitochondrial dihydrolipoic acid dehydrogenase, isovaleryl coenzyme A dehydrogenase, glutathione synthetase, mitogen-activated protein kinase 3 and so on. Compared with the control group, the mRNA expression of methylmalonic acid semialdehyde dehydrogenase in the atrial muscle of rats was decreased after 4 weeks of moderate aerobic exercise ( P <0.05), the mRNA expression levels of mitochondria Ⅱ lipoic acid dehydrogenase, protein disulfide isomerase A3, mitochondrial aconitate hydratase and glutathione synthetase were decreased ( P >0.05); The mRNA expression level of isopentenyl-CoA dehydrogenase was increased ( P >0.05). The results indicated that the mRNA expression level was not completely consistent with the changes in mass spectrometry identification results., Conclusions: The 4 weeks moderate-intensity aerobic exercise induced ignificant changes of rats atrial muscle protemics. The majority of the 13 identified target proteins in this experiment are energy metabolism enzymes. The majority of the expression of the target protein and the mRNA expression in the atrial muscle is inconsistent and different. Exercise may affect the regulation of gene transcription or downstream translation and modification of these target proteins, resulting in the change of differential expression.

Hepatitis B virus X protein (HBx) is involved in the pathogenesis of hepatocellular carcinoma (HCC). Overexpression of the transcripts from the P3 and P4 promoters of the insulin-like growth factor-II (IGF-II) gene is observed in HCC. The present study investigated the involvement of HBx in IGF-II overexpression and its epigenetic regulation. Firstly, the effects of HBx on P3 and P4 mRNA expression, the methylation status of the P3 and P4 promoters, and MBD2 expression were analyzed in human HCC cells and HCC samples. Next, interaction between HBx and MBD2 or CBP/p300 was assessed by co-immunoprecipitation, and HBx-mediated binding of MBD2 and CBP/p300 to the P3 and P4 promoters and the acetylation of the corresponding histones H3 and H4 were evaluated by quantitative chromatin immunoprecipitation. Finally, using siRNA knockdown, we investigated the roles of MBD2 and CBP/p300 in IGF-II overexpression and its epigenetic regulation. Our results showed that HBx promotes IGF-II expression via inducing the hypomethylation of the P3 and P4 promoters, and that HBx increases MBD2 expression, directly interacts with MBD2 and CBP/p300, and elevates their recruitment to the hypomethylated P3 and P4 promoters with increased acetylation levels of the corresponding histones H3 and H4. Further results showed that endogenous MBD2 and CBP/p300 are necessary for HBx-induced IGF-II overexpression and that CBP/p300 presence and CBP/p300-mediated acetylation of histones H3 and H4 are partially required for MBD2 binding and its demethylase activity. These data suggest that HBx induces MBD2-HBx-CBP/p300 complex formation via interaction with MBD2 and CBP/p300, which contributes to the hypomethylation and transcriptional activation of the IGF-II-P3 and P4 promoters and that CBP/p300-mediated acetylation of histones H3 and H4 may be a rate-limiting step for the hypomethylation and activation of these two promoters. This study provides an alternative mechanism for understanding the pathogenesis of HBx-mediated HCC.

Objective: To explore the morbidity of hypertension and prehypertension and analyze the association between body mass index (BMI) and blood pressure in Chinese college students., Methods: This epidemiological study involved 490 Chinese college students (aged 15-25 years, mean 18.9∓1.2 years), and their body height, body weight, blood pressure and heart rate were recorded. The BMI was divided into four groups according to Chinese population standard classification., Results: Most students were southern Han Chinese. The incidences of overweight plus obesity and obesity were 12.9% and 4.1%, respectively. The morbidity of hypertension was 0.8% in this student population. The incidences of hypertension and pre-hypertension were higher in high BMI groups than those in low BMI groups. The systolic blood pressures were significantly higher in over-weight and obese groups than in the normal BMI and lean groups. BMI was positively correlated to systolic and diastolic blood pressures in this population., Conclusion: High BMI is a predictor of elevated blood pressure in adolescent students.

Objective: To develop 22 Chinese Mandarin monosyllable lists with good psychometrical equivalence. This study was to evaluate the test-retest reliability of these lists when it was used in speech recognition test in normal hearing dialectal speakers., Methods: Seven cities including Dalian, Shanghai, Hangzhou, Wuhan, Guangzhou, Fuzhou and Xiamen were selected as testing centers which contain 6 typical Chinese dialectal regions including north of China, East of China, north of Fujian, south of Fujian, Guangdong and mid-south of China. At each center, 22 local normal hearing people were selected to join this study. Every participant was tested by each recognition test of all 22 lists twice in two sessions and same test order respectively. The second run of testing was carried out within 10 days-1 month since first run of testing., Results: There was a significant correlations between scores obtained at the two sessions (r = 0.682, P < 0.01). Paired student-t test had shown that a gross score of all dialectal participants was significantly higher than that of initial test to retest (P < 0.01). The mean increment of score was (2.7 +/- 10.1)%. A significant difference of test-retest score in 7 sites was 19.8% and it was equal to 5 test items. A one way ANOVA analysis had indicated that there were statistically significant difference between the score improvement of 7 test sites (P < 0.01). Another analysis had shown that there was no significant correlation between test-retest score improvement and intra-session intervals (P = 0.947)., Conclusions: Mandarin monosyllabic recognition test seems to be more stable, and the present study has indicated a systematic differences in Chinese Mandarin monosyllable recognition scores between test and retest. Monosyllable recognition test is not susceptible to memory effect. Pearson's correction analysis is not suitable to evaluation for test-retest reliability.