Objective To establish a doxycycline-controlled immortalized pre-cartilaginons stem cells (IPCSCs) strains, clone parathroid hormone-related peptide[PTHrP(1-36)] gene and construct re- sponsive plasmid, pTRE-PTHrP (1-36). Methods Plasmid pTet-on was transfected into IPCSCs by using LipoinfectaminTM 2000 and then the stable clones were obtained by G418 screening. The doxycyc- line was added into the medium of monoclonal cells that were transiently transfected with plasmid pTRE- 2Hyg-Lue. The total RNA was extracted from PCSCs and the PTHrP(1-36) gene obtained by RT-PCR method. Then, the PTHrP (1-36) gene was subcloned to plasmids of Tet-responsive element with the se- lection marker of hygromycin pTRE-2Hyg to construct recombinant eukaryotic expression plasmid pTRE- PTHrP(1-36). After transferred into E. coli-DH5α, the clone was amplified, the recombinant plasm0ids were purified and identified by double-enzyme digestion. Results The doxycycline induced IPCSCs line was obtained, with 50 times higher than the non-induced cell line. Double enzyme digestion analysis and sequencing showed that the target gene was cloned into recombinant plasmid. Conclusions The induced IPCSCs line can be used to highly express alien genes. The responsive plasmid containing PTHrP (1-36) gene may be premising for rigorous control of PTHrp (1-36) gene expression.

Objective:To analyze the causal relationship between lifestyle-based factors and the occurrence and development of hepatobiliary malignancies by Mendelian randomization study method,and to provide the potential clinical evidence for the prevention and treatment of hepatobiliary malignancies.Methods:The data from large-scale,independent genome-wide association studies(GWAS)were selected,and seven-step inclusion criteria for the instrumental variable screening were set up.The exposure lifestyles included the percentage of carbohydrate intake,percentage of fat intake,percentage of protein intake in the diet,coffee intake,weekly alcohol consumption times,leisure electronic screen exposure time,moderate to vigorous intensity physical activity(MVPA)during leisure time,sedentary behavior at work,age at first smoking,daily smoking quantity,current smoking status,and past smoking status,totaling 12 phenotypes.The primary analysis method used was the random effect model of the inverse variance weighted(IVW)method,and the heterogeneity was detected by Cochrane's Q test and the horizontal pleiotropy was detected by MR-Egger intercept method.Results:The current smoking status was significantly positively correlated with the increasing risk of extrahepatic cholangiocarcinoma(OR=1.607,95%CI:1.113-2.322,P=0.011).Higher coffee intake was causally linked to a higher risk of liver cancer and intrahepatic cholangiocarcinoma(OR=1.000,95%CI:0.999-1.000,P=0.012).In the physical activity,more MVPA was associated with the lower risk of liver cancer and intrahepatic cholangiocarcinoma(OR=0.998,95%CI:0.996-0.999,P=0.002).The Cochrane's Q test results showed that there was mild heterogeneity between MVPA and extrahepatic cholangiocarcinoma(Q=18.354,P=0.049)as well as the percentage of protein intake and intraphepatic cholangiocarainoma(Q=12.715,P=0.026),and the MR-Egger intercept method results showed there was no horizontal pleiotropy.Conclusion:There is a causal relationship between current smoking status and extrahepatic cholangiocarcinoma,and there is a causal relationship between more MVPA and the lower risk of liver cancer and intrahepatic cholangiocarcinoma.Education on smoking and physical activity for the patients may offer potential benefits for the prevention of hepatobiliary malignancies.

Objective:To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China.Methods:Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust.Results:The M ( Q1,Q3) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑ 12PBDEs in Luoyang and Shijiazhuang ( P<0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ β (95% CI): 0.186 (0.013, 0.359)], infrequent home cooking [ β (95% CI):-0.342 (-0.570, -0.114)], and increased residential PM 10 concentration [ β (95% CI): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ β (95% CI): 0.093 (0.013, 0.172)], house area less than 90 m 2 [ β (95% CI):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ β (95% CI):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑ 12PBDEs in household dust. Conclusion:The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM 10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.

Objective:To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China.Methods:Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust.Results:The M ( Q1,Q3) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑ 12PBDEs in Luoyang and Shijiazhuang ( P<0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ β (95% CI): 0.186 (0.013, 0.359)], infrequent home cooking [ β (95% CI):-0.342 (-0.570, -0.114)], and increased residential PM 10 concentration [ β (95% CI): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ β (95% CI): 0.093 (0.013, 0.172)], house area less than 90 m 2 [ β (95% CI):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ β (95% CI):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑ 12PBDEs in household dust. Conclusion:The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM 10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.

Objective:To analyze the clinical characteristics of adult Chinese patients with syncope.Methods:This is a cross-sectional survey study. Patients with preliminary diagnosis of syncope in the Emergency Department, Geriatrics and Cardiology Outpatient Department, or Syncope Unit of 37 hospitals in 19 provinces, autonomous regions and the Hong Kong Special Administrative Region from June 2018 to March 2021 were included in this study. The clinical features of these patients with syncope were analyzed.Results:A total of 4 950 consecutive patients with syncope were included in this study. The age was (56.3±16.8)years, and 2 604 cases (52.6%) were male. The most common type of syncope was neurally mediated syncope (2 345 (47.4%)), followed by cardiac syncope (1 085 (21.9%)), orthostatic hypotensive syncope (311 (6.3%)), and unexplained syncope accounted for nearly one third (1 155 (23.3%)). Predisposing syncope was more common in patients under 65 years of age(2 066(72.4%) vs. 786(27.6%),χ 2=136.5, P<0.001). Presyncope was more common in patients with neurally mediated syncope (1 972(79.0%) vs.1 908(73.9%), χ 2=17.756, P<0.001). Premonitory symptoms were more common in women(1 837(80.0%) vs. 1 863(73.0%),χ 2=33.432, P<0.001). Presyncope syndrome was more common in patients under 65 years of age (2 482(77.8%) vs. 1 218(73.4%),χ 2=17.523, P=0.001). Cyanosis was more common in ≥65 years old patients (271(18.2%) vs. 369(12.7%), χ 2=23.235, P<0.001). Urinary incontinence was more common in old patients aged ≥65 years(252(15.2%) vs. 345(10.8%), χ 2=19.313, P<0.001). Family history was more common in patients with cardiogenic syncope compared with other types of syncope (264(24.3%) vs. 754(19.5%), χ 2=11.899, P=0.001). Hypertention(1 480(30.5%)), coronary heart disease(1 057(21.4%)), atrial flutter and atrial fibrillation(359(7.2%)), second degree atrioventricular block(236(4.8%)) were common complications of syncope. The proportion of patients with coronary heart disease was significantly higher in cardiac syncope than that of other types of syncope(417(38.4%) vs. 640(16.6%), χ 2=241.376, P<0.001). Other common complications included cerebrovascular diseases (551 (11.1%)) and diabetes mellitus (632(12.8%)). Conclusions:Neurally mediated syncope is the most common syncope in adult Chinese population. Patients with predisposing conditions and premonitory conditions are younger. Presyncope is more common in women. The proportion of family history and coronary heart disease is higher in patients with cardiogenic syncope.