ObjectiveTo investigate the association between cumulative atherogenic index of plasma （cumAIP） and the risk of new-onset nonalcoholic fatty liver disease （NAFLD） in young and middle-aged individuals. MethodsA prospective cohort study was conducted among the young and middle-aged individuals （aged 18 to <60 years） in the Kailuan study cohort who underwent physical examination in Kailuan General Hospital and its 10 affiliated hospitals in June 2006 to October 2010， and after screening based on the inclusion and exclusion criteria， 33 987 individuals were included in the observation cohort. The individuals were divided into Q1， Q2， Q3， and Q4 groups based on the quantiles of cumAIP. The Kaplan-Meier method was used to calculate the cumulative incidence rate of new-onset NAFLD in the four groups， while the log-rank test was used for comparison between groups. A multivariate Cox regression analysis was used to obtain the hazard ratio （HR） and 95% confidence interval （CI） of the risk of new-onset NAFLD in the four groups. A one-way analysis of variance was used for comparison of normally distributed continuous data between multiple groups， and the Kruskal-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups； the chi-square test was used for comparison of categorical variables between groups. ResultsThe mean follow-up was 10.89±2.54 years， and there were 6 011 cases of new-onset NAFLD， including 995 cases in the Q1 group， 1 366 in the Q2 group， 1661 in the Q3 group， and 1 989 in the Q4 group， with an incidence density of 11.37， 16.02， 19.97， and 24.91 per thousand person-years. The log-rank test showed that there was a significant difference in cumulative incidence rate between the four groups （P<0.001）. With the presence or absence of NAFLD as the dependent variable and the quantiles of different exposure levels to cumAIP as the independent variable， the multivariate Cox regression model analysis showed that compared with the Q1 group， the Q2， Q3， and Q4 groups had an HR of 1.30 （95%CI： 1.20 — 1.41）， 1.52 （95%CI： 1.41 — 1.65）， and 1.79 （95%CI： 1.64 — 1.95）， respectively， for new-onset NAFLD， with a P_trend value of <0.001. With the presence or absence of new-onset NAFLD as the dependent variable and the cumulative exposure to AIP for 0， 2， 4， and 6 years as the independent variable， the Cox regression analysis showed that compared with cumulative exposure to AIP for 0 years， cumulative exposure to AIP for 2， 4， and 6 years had an HR of 1.24 （95%CI： 1.15 — 1.35）， 1.51 （95%CI： 1.40 — 1.64）， and 1.70 （95%CI： 1.56 — 1.84）， respectively， with a P_trend value of <0.001. A sensitivity analysis was performed after exclusion of the individuals with new-onset NAFLD within 2 years， the individuals who experienced atherosclerotic cardiovascular disease events during follow-up， and the individuals taking antihypertensive， hypoglycemic， and lipid-lowering drugs， and the results were similar to those of the main analysis. Considering the competitive relationship between all-cause death and outcome events， a competing risk analysis of death was performed， which showed that the results of risk analysis were similar to those of the main analysis. ConclusionA high level of cumAIP exposure can increase the risk of new-onset NAFLD in young and middle-aged individuals.

Exonuclease Ⅷ (Exo Ⅷ), an ATP-independent dsDNA 5'-3' exonuclease, is a candidate protein with great application value for in vitro DNA recombination. However, the application of Exo Ⅷ in DNA recombination in vitro has not been reported. In this study, the recombinant expression vector of the truncated Exo Ⅷ (tExo Ⅷ) with the full exonuclease activity was built and used to achieve the overexpression of tExo Ⅷ in Escherichia coli. Based on the purified tExo Ⅷ protein with high-purity, the feasibility of tExo Ⅷ applied in vitro DNA recombination and effects of the reaction temperatures, reaction duration, and homology arm lengths were examined. The results showed that tExo Ⅷ was highly expressed in soluble form in E. coli. One liter of bacterial culture yielded 92.40 mg of purified tExo Ⅷ with the specific activity of 1.21×10⁵ U/mg. In a 10 μL recombination system containing 2.5 U tExo Ⅷ, the highest cloning efficiency was achieved in a reaction at 25 °C for 12.5 min and followed by incubation at 50 °C for 50 min. With addition of Pfu DNA polymerase, the homology arm extension strategy can effectively improve the recombination efficiency. Using competent E. coli Mach1 T1 with 2.2×10⁶ cfu/μg transformation efficiency as recipient cell, the recombination of a 1 kb fragment with a 21 bp homology arm and a 5.8 kb linearized vector can form about 1.1×10⁴ recombinant clones per μg vector, and the positive rates was over 80%. The recombination efficiency was increased with the increasing length of homology arm ranged from 8 to 21 bp. Under the optimal reaction condition, only 8 bp homology arm can still achieve valid DNA recombination. This novel in vitro DNA recombination system mediated by tExo Ⅷ was particularly characterized by its easy preparation, no limitation on restriction sites and high recombination cloning efficiency. All results revealed that the new efficient gene cloning system has potential application in the field of molecular biology.
Cloning, Molecular ; Escherichia coli ; genetics ; Exonucleases ; genetics ; Recombinant Proteins ; metabolism ; Recombination, Genetic

Objective To investigate the feasibility of the upper- arm electronic sphygmomanometer for evaluating the blood pressure in patients with atrial fibrillation. Methods Consecutive hospitalized patients with atrial fibrillation for coronary angiography were selected, and the application of upper- arm electronic sphygmomanometer and mercury sphygmomanometer of blood pressure were applied and in the process of coronary angiography, the radial artery invasive blood pressure was recorded and the correlation was analyzed. Results Mercury sphygmomanometer and radial artery invasive blood pressure measurement had a good consistency on systolic blood pressure, diastolic blood pressure, pulse pressure, mean arterial pressure in atrial fibrillation patients, the differences were not statistically significant (P>0.05). Upper- arm electronic sphygmomanometer and radial artery invasive blood pressure measurement had some consistency (pulse rate range, pulse rate of 70-90 beats / min) on systolic blood pressure, diastolic blood pressure, pulse pressure, mean arterial pressure in atrial fibrillation patients, the differences were not statistically significant (P>0.05). Upper-arm electronic sphygmomanometer and mercury sphygmomanometer had some consistency (pulse rate range, pulse rate of 70-90 beats / min) on systolic blood pressure, diastolic blood pressure, pulse pressure, mean arterial pressure in atrial fibrillation patients, the differences were not statistically significant (P>0.05). The correlation between mercury sphygmomanometer and radial artery invasive blood pressure measurement were found on systolic blood pressure, diastolic blood pressure, pulse pressure, mean arterial pressure in atrial fibrillation patients (r=0.71-0.78, P<0.05),which were better than those of upper- arm electronic sphygmomanometer and radial artery invasive blood pressure measurement (r=0.53-0.70, P <0.05). Conclusions The upper- arm electronic sphygmomanometer can be used for the assessment of blood pressure in patients with atrial fibrillation.

Objective: To study the risk factors for prevalence of acute myocardial infarction (AMI) in young and middle-aged population. Methods: A prospective cohort study was conducted in 110100 subjects at the age of (18-98) years who received physical examination in Kailuan Group from 2012-06 to 2014-10. Based on the limitations of male≤53 years and female≤63 years, a total of 62367 subjects were enrolled in our study. The subjects were followed-up for 2 years by the end point event of AMI to analyze the risk factors ofAMI occurrence. Results: According to AMI occurrence at the follow-up period, the subjects were divided into 2 groups: AMI group, n=56 and Control group, n=62152. Compared with Control group, AMI group had increased BMI, SBP, DBP and elevated blood levels of LDL-C, TG; AMI group also showed the higher ratios of subjects with the history of diabetes and taking anti-hypertension medication. Cox proportional hazard regression analysis indicated that age (RR=1.37), male (RR=60.54), LDL-C (RR=1.12), and TG (RR=5.93) were the risk factors forAMI occurrence in young and middle-aged population, allP<0.05. Conclusion: Age, male gender, blood levels of LDL-C, and TG were the risk factors for AMI occurrence in young and middle-aged population.