ObjectiveTo investigate the association between metabolic associated fatty liver disease （MAFLD） and the risk of atherosclerotic cardiovascular disease （ASCVD）， and to provide data support for the prevention and treatment of such metabolic-associated diseases in clinical practice. MethodsAn observation cohort was established for the workers of Kailuan who underwent physical examination for the first time from June 2006 to October 2007 and had complete liver assessment data， without the history of malignant tumor， MAFLD or ASCVD. According to the presence or absence of MAFLD， the patients were divided into non-MAFLD group with 67 565 patients and MAFLD group with 29 004 patients， and according to the presence or absence of ASCVD， the patients were divided into non-ASCVD group with 69 141 patients and ASCVD group with 481 patients. The group t-test or the Wilcoxon rank-sum test was used for comparison of continuous data between the two groups. The χ² test was used for comparison of categorical data between the two groups. The life-table method was used to calculate the cumulative incidence rates of new-onset ASCVD and MAFLD； the Kaplan-Meier method was used to plot the survival curves of the cumulative incidence rates of ASCVD in the MAFLD group and the non-MAFLD group and the cumulative incidence rates of MAFLD in the ASCVD group and the non-ASCVD group， and the log-rank test was used for comparison of cumulative incidence rates between two groups. A multivariate Cox proportional-hazards regression model analysis was used to investigate the impact of MAFLD on the risk of ASCVD and the impact of ASCVD on the risk of MAFLD. ResultsCompared with the non-MAFLD group， the MAFLD group had significantly higher levels of body mass index （BMI）， waist circumference， systolic blood pressure （SBP）， diastolic blood pressure （DBP）， resting heart rate， alanine aminotransferase， uric acid （UA）， fasting blood glucose （FBG）， triglyceride （TG）， total cholesterol， low-density lipoprotein cholesterol， and high sensitivity C-reactive protein （hs-CRP）， as well as significanty lower levels of estimated glomerular filtration rate （eGFR） and high-density lipoprotein cholesterol （all P <0.05）. Compared with the non-ASCVD group， the ASCVD group had significantly higher levels of BMI， waist circumference， SBP， DBP， UA， FBG， TG， and hs-CRP and a significantly lower level of eGFR （all P<0.05）. The incidence rate of new-onset ASCVD continued to increase over time in the MAFLD group and the non-MAFLD group， while the incidence rate of new-onset MAFLD firstly increased and then remained stable over time in the ASCVD group and the non-ASCVD group. There were 4 263 cases （14.70%） of new-osnet ASCVD in the MAFLD group， with an incidence density of 12.90 per 1 000 person-years， while there were 6 529 cases （9.66%） of new-osnet ASCVD in the non-MAFLD group， with an incidence density of 8.24 per 1 000 person-years， and there were significant differences in the incidence density and cumulative incidence rate of ASCVD between the two groups （χ²=519.09 and 531.80， both P<0.05）. There were 148 cases （30.77%） of new-onset MAFLD in the ASCVD group， with an incidence density of 40.10 per 1 000 person-years， while there were 32 194 cases （46.56%） of new-onset MAFLD in the non-ASCVD group， with an incidence density of 57.59 per 1 000 person-years， and there were significant differences in the incidence density and cumulative incidence rate of MAFLD between the two groups （χ²=19.29 and 30.78， both P<0.05）. The corrected multivariate Cox proportional-hazards regression model analysis showed that MAFLD was a risk factor for new-onset ASCVD （hazard ratio ［HR］=1.11， 95% confidence interval ［CI］： 1.06 — 1.16， P<0.001）， while ASCVD was a protective factor against new-onset MAFLD （HR=0.72， 95%CI： 0.61 — 0.85， P<0.001）. ConclusionThere is a significant association between MAFLD and ASCVD， with an increase in the risk of ASCVD in the MAFLD population and a reduction in the risk of MAFLD in the ASCVD population.

Objectives:To investigate the association between the triglyceride-glucose(TyG)index and risk of non-alcoholic fatty liver disease(NAFLD)in young and middle-aged(<60 years)adults.Methods:From June 2006 to October 2007,47 675 employees of Kailuan Group with no liver disease were selected as the study objects.Based on the TyG index quartile,participants were divided into Q1 group(TyG index≤8.08,n=11 924),Q2 group(8.0836.46,n=11 919),the association between TyG index,cum-TyG and cumulative exposure time and the risk of NAFLD was analyzed.Results:The average age of the study population was(44.3±8.7)years,36 345 participants were males(76.23%).During a median follow-up period of 11.55(7.28,13.89)years,4 635(9.72%)participants developed new-onset NAFLD.After adjusting for confounders,cox regression analysis showed that compared with the Q1 group,the HR(95%CI)for NAFLD in the Q2 to Q4 groups were 1.328(1.191-1.480),1.591(1.430-1.770),and 2.106(1.861-2.384),respectively,Ptrend<0.001.Compared with the cum-Q1 group,the HR(95%CI)for NAFLD in the cum-Q2 to cum-Q4 groups were 1.571(1.426-1.730),2.123(1.935-2.330)and 2.593(2.367-2.840),respectively,Ptrend<0.001.Compared with the TyG index for 0 year,the HR(95%CI)of NAFLD for 2,4 and 6 years was 1.333(1.196-1.486),1.879(1.690-2.088)and 3.184(2.860-3.545),respectively,Ptrend<0.001.Conclusions:Increased TyG index is an independent risk factor for the new-onset NAFLD in young and middle-aged population.

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.

Objectives:To investigate the correlation between resting heart rate(RHR)and atherosclerotic cardiovascular disease(ASCVD)and all-cause death in young and middle-aged people.Methods:A prospective cohort study was conducted enrolling 72 642 young and middle-aged participants(aged<60 years),who participated in the medical examination of the Kailuan Study from June 2006 to October 2007.According to the quartile of the RHR level,the participants were divided into Q1 group(<67 beats/min,n=14 381),Q2 group(67-70 beats/min,n=15 815),Q3 group(71-75 beats/min,n=15 876),Q4 group(76-80 beats/min,n=13 933)and Q5 group(>80 beats/min,n=12 637).Cox proportional hazard regression model was used to analyze the effect of RHR on ASCVD and all-cause death.The dose-response relationship between RHR and the risk of ASCVD and all-cause death was investigated using a restricted cubic spline regression model.Results:During a mean follow-up of(10.0±4.85)years,2 898 patients(3.99%)developed ASCVD.Multivariate Cox regression analysis showed that after adjusting for confounding factors,the risk of RHR and ASCVD in group Q5 increased by 20%compared with group Q1(HR=1.20,95%CI:1.06-1.35,P<0.05).There was no significant risk in groups Q2 to Q4 compared to Q1 group(all P>0.05).In addition,the risk of ASCVD increased by 4%for every 10 beats/min increase in RHR(HR=1.04,95%CI:1.01-1.07,P=0.009).During the follow-up period of(10.2±4.82)years,all-cause death occurred in 2 175 participants(2.99%).The results showed that compared with Q1 group,the risk of all-cause death in Q3 to Q5 groups increased by 33%(HR=1.33,95%CI:1.15-1.54,P<0.001),33%(HR=1.33,95%CI:1.14-1.54,P<0.001),and 78%(HR=1.78,95%CI:1.54-2.05,P<0.001)respectively,and there was no statistical significance between group Q2 and group Q1.The risk of all-cause death increased by 15%for every 10 beats/min increase in RHR(HR=1.15,95%CI:1.11-1.19,P<0.001).Restricted cubic spline analysis showed that RHR was linearly correlated with risk of ASCVD(Poverall=0.022,Pnon-linear=0.617),and the risk of ASCVD increased significantly with RHR>72 beats/min.RHR was linearly associated with the risk of all-cause death(Poverall<0.001,Pnon-linear=0.212),and the risk of all-cause death was significantly increased with RHR>72 betas/min.Conclusions:Higher RHR is associated with an increased risk of ASCVD and all-cause mortality in young and middle-aged individuals.

Objectives:To investigate the correlation between resting heart rate(RHR)and atherosclerotic cardiovascular disease(ASCVD)and all-cause death in young and middle-aged people.Methods:A prospective cohort study was conducted enrolling 72 642 young and middle-aged participants(aged<60 years),who participated in the medical examination of the Kailuan Study from June 2006 to October 2007.According to the quartile of the RHR level,the participants were divided into Q1 group(<67 beats/min,n=14 381),Q2 group(67-70 beats/min,n=15 815),Q3 group(71-75 beats/min,n=15 876),Q4 group(76-80 beats/min,n=13 933)and Q5 group(>80 beats/min,n=12 637).Cox proportional hazard regression model was used to analyze the effect of RHR on ASCVD and all-cause death.The dose-response relationship between RHR and the risk of ASCVD and all-cause death was investigated using a restricted cubic spline regression model.Results:During a mean follow-up of(10.0±4.85)years,2 898 patients(3.99%)developed ASCVD.Multivariate Cox regression analysis showed that after adjusting for confounding factors,the risk of RHR and ASCVD in group Q5 increased by 20%compared with group Q1(HR=1.20,95%CI:1.06-1.35,P<0.05).There was no significant risk in groups Q2 to Q4 compared to Q1 group(all P>0.05).In addition,the risk of ASCVD increased by 4%for every 10 beats/min increase in RHR(HR=1.04,95%CI:1.01-1.07,P=0.009).During the follow-up period of(10.2±4.82)years,all-cause death occurred in 2 175 participants(2.99%).The results showed that compared with Q1 group,the risk of all-cause death in Q3 to Q5 groups increased by 33%(HR=1.33,95%CI:1.15-1.54,P<0.001),33%(HR=1.33,95%CI:1.14-1.54,P<0.001),and 78%(HR=1.78,95%CI:1.54-2.05,P<0.001)respectively,and there was no statistical significance between group Q2 and group Q1.The risk of all-cause death increased by 15%for every 10 beats/min increase in RHR(HR=1.15,95%CI:1.11-1.19,P<0.001).Restricted cubic spline analysis showed that RHR was linearly correlated with risk of ASCVD(Poverall=0.022,Pnon-linear=0.617),and the risk of ASCVD increased significantly with RHR>72 beats/min.RHR was linearly associated with the risk of all-cause death(Poverall<0.001,Pnon-linear=0.212),and the risk of all-cause death was significantly increased with RHR>72 betas/min.Conclusions:Higher RHR is associated with an increased risk of ASCVD and all-cause mortality in young and middle-aged individuals.

Objectives:To investigate the association between the triglyceride-glucose(TyG)index and risk of non-alcoholic fatty liver disease(NAFLD)in young and middle-aged(<60 years)adults.Methods:From June 2006 to October 2007,47 675 employees of Kailuan Group with no liver disease were selected as the study objects.Based on the TyG index quartile,participants were divided into Q1 group(TyG index≤8.08,n=11 924),Q2 group(8.0836.46,n=11 919),the association between TyG index,cum-TyG and cumulative exposure time and the risk of NAFLD was analyzed.Results:The average age of the study population was(44.3±8.7)years,36 345 participants were males(76.23%).During a median follow-up period of 11.55(7.28,13.89)years,4 635(9.72%)participants developed new-onset NAFLD.After adjusting for confounders,cox regression analysis showed that compared with the Q1 group,the HR(95%CI)for NAFLD in the Q2 to Q4 groups were 1.328(1.191-1.480),1.591(1.430-1.770),and 2.106(1.861-2.384),respectively,Ptrend<0.001.Compared with the cum-Q1 group,the HR(95%CI)for NAFLD in the cum-Q2 to cum-Q4 groups were 1.571(1.426-1.730),2.123(1.935-2.330)and 2.593(2.367-2.840),respectively,Ptrend<0.001.Compared with the TyG index for 0 year,the HR(95%CI)of NAFLD for 2,4 and 6 years was 1.333(1.196-1.486),1.879(1.690-2.088)and 3.184(2.860-3.545),respectively,Ptrend<0.001.Conclusions:Increased TyG index is an independent risk factor for the new-onset NAFLD in young and middle-aged population.

Objective To investigate whether suffering from atrial fibrillation in different ages of people increasing the onset risk of new-onset acute myocardial infarction(AMI).Methods A prospective cohort study was conducted to select 96 624 Kailuan Group employees undergoing the health examination from June 2006 to October 2007 for including the study.The participants were followed up once a year,and the last fol-low-up date was December 31,2020,with a median follow-up of 14.01 years,and the endpoint event was new-onset AMI.The participants were divided into two age groups according to the age ≥60 years and the age＜60 years old,and divided into the atrial fibrillation group and non-atrial fibrillation group according to whether they had atrial fibrillation.The epidemiological investigation and anthropometric measurements were carried out on the participates.Whether atrial fibrillation was correlated to the onset of new-onset AMI in different age groups conducted the statistical analysis.Results Among the total participants,there were 411 cases in the atrial fibrillation group and 96 213 cases in the non-atrial fibrillation group.Among the participants＜60 years old,there were 121 cases in the atrial fibrillation group and 75 151 cases in the non-atrial fibrillation group.Among the participants ≥60 years old,there were 290 cases in the atrial fibrillation group and 21 062 cases in the non-atrial fibrillation group.In the total participants,the cumulative incidence rate of AMI in the atrial fibrillation group was higher than that in the non-atrial fibrillation group(5.68％vs.1.92％),and the difference was statistically significant(P＜0.05).In the participants＜60 years old,the cumulative incidence rate of AMI in the atrial fibrillation group was higher than that in the non-atrial fibrillation group(7.40％vs.1.43％),and the difference was statistically significant(P＜0.05).In the participants 60 year old,the cu-mulative incidence rate of AMI had no statistical difference between the atrial fibrillation group and non-atrial fibrillation group(4.54％vs.3.87％,P=0.547).In the whole participants,atrial fibrillation was a risk factor for new-onset AMI(HR=1.877,95％CI:1.177-2.991,P=0.008),and there was an interaction between age and atrial fibrillation(P=0.016).In the age stratification analysis,atrial fibrillation was a risk factor for new-onset AMI in＜60-year-old population(HR=3.029,95％CI:1.508-6.082,P=0.002).Conclusion Atrial fibrillation is an independent risk factor for new-onset AMI,especially to young and middle-aged people(＜60 years old).

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.