Objective_To study the effect of human insulin on cell cycle progression and apoptosis of rat liver cell line BRL-3A in vitro.Methods_MTT method was used to observe the effect of insulin on cell activity, and flow cytometry was used to detect cell apoptosis and cell cycle.qRT-PCR was used to evaluate the expression of related genes.Results_Human insulin induced the proliferation of BRL-3A cells in a dose-dependent manner ( P<0.05 or P<0.01);After 3 days treated by human insulin (500 nmol/L), the proportion of cells in G0/G1 phases re-markably decreased (P<0.05).Moreover, pro-apoptotic BAX was down-regulated (P<0.05), while cell prolif-eration-related gene CCNA2 was up-regulated (P<0.05).Conclusions_Human insulin may inhibit the apoptosis of BRL-3 A cell line and induce proliferation due to the down-regulated expression of BAX and up-regulated expres-sion of CCNA2 .

This study evaluated the change in regional left ventricular myocardial function in rats following acute occlusion of the left anterior descending coronary artery (LAD) by using two-dimensional speckle tracking imaging (2D-STI). Sixty Wistar rats were randomly divided into two groups, a myocardial infarction (MI) group, in which 50 rats were subjected to LAD occlusion for 30-45 min, and a sham-operated (SHAM) group that contained 10 rats serving as control. Echocardiography was performed at baseline and 1, 4 and 8 week(s) after the operation. High frequency two-dimensional images of left ventricular short axis at papillary muscle level were recorded. Peak systolic radial strain (PRS) and circumferential strain (PCS) were measured in the mid-ventricle in short-axis view by using EchoPAC workstation. Left ventricular internal diameter at diastole (LVIDd) and systole (LVIDs), fractional shortening (FS), ejection fraction (EF) and left ventricular mass (LVM) were measured by anatomical M-model echocardiography. Infarct size was measured using triphenyl tetrazolium chloride (TTC) staining 1 week and 8 weeks after the operation. Fibrosis of left ventricular myocardium was displayed using Van Gieson staining 1 week after the infarction. In terms of the TTC staining results, the left ventricle fell into three categories: infarcted, peri-infarcted and remote myocardial regions. Compared with those at baseline and in the SHAM group, (1) PRS and PCS in the infarcted, peri-infarcted and remote myocardial regions were significantly decreased in the MI group within 1 week after the operation (P<0.05) and the low levels lasted 8 weeks; (2) Compared with those at baseline, LVIDd, LVIDs, FS, EF and LVM in the MI group showed no significant difference 1 week after the operation (P>0.05). However, LVIDd, LVIDs and LVM were increased significantly 4 and 8 weeks after the operation (P<0.05), and FS and EF were decreased substantially (P<0.05). Van Gieson staining showed that fibrosis developed in all the three myocardial regions to varying degrees. It is concluded that 2D-STI is non-invasive and can be used to assess regional function of myocardium with different blood supply in rats following acute occlusion of the LAD, and can be used as a sensitive and reliable means to follow up the process of left ventricular remodeling.

Objective:To research the association between exposure to solid fuels for heating and its duration and the risk of respiratory diseases morbidity.Methods:Data from the China Kadoorie Biobank project sited in Pengzhou City, Sichuan Province. Cox proportional hazard regression model was used to analyze the association between exposure to solid fuels for heating and its duration and the risk of total respiratory diseases and the association between exposure to solid fuels for heating and the risk of chronic obstructive pulmonary disease (COPD) and pneumonia among respiratory diseases.Results:A total of 46 082 participants aged 30-79 years were enrolled, with 11 634 (25.25%) heating during the winter, of whom 8 885 (19.28%) used clean fuels and 2 749 (5.97%) used solid fuels, of whom 34 448 (74.75%) did not heat. After controlling for multiple confounding factors, Cox proportional hazard regression model was used, which revealed that compared with clean fuels, unheating could reduce the risk of total respiratory disease ( HR=0.81,95% CI:0.77-0.86), COPD ( HR=0.86,95% CI:0.78-0.95) and pneumonia ( HR=0.80,95% CI:0.74-0.86), respectively. Exposure to solid fuels increased the risk of total respiratory disease ( HR=1.10, 95% CI:1.01-1.20) and were not associated with COPD and pneumonia. Compared with no solid fuel exposure, the risk of total respiratory disease (1-19 years: HR=1.23, 95% CI:1.10-1.37; 20-39 years: HR=1.25, 95% CI:1.16-1.35; ≥40 years: HR=1.26, 95% CI:1.15-1.39) and COPD (1-19 years: HR=1.21, 95% CI:1.03-1.42; 20-39 years: HR=1.30, 95% CI:1.16-1.46; ≥40 years: HR=1.35, 95% CI:1.18-1.54) increased with the length of exposure of solid fuels (trend test P<0.001). Solid fuels exposure for 1-19 years and 20-39 years increased the risk of COPD by 23% ( HR=1.23,95% CI:1.02-1.49) and 16% ( HR=1.16, 95% CI:1.00-1.35). Conclusion:Heating solid fuels exposure increases the risk of total respiratory disease, COPD, and pneumonia.

Objective To describe the relationships between dietary cholesterol and serum cholesterol among Chinese adults.Methods Data used in the present study was from the China Health and Nutrition Study (CHNS).Chinese adults,18 to 65 year olds who participated in the 2009 CHNS with complete individual information were included in the study.Correlation of dietary cholesterol and serum cholesterol among different sex groups was described to explore the effect of dietary cholesterol intake on the level of serum cholesterol as well as to examine the effect of higher intake of dietary cholesterol related to hypercholesterolemia.Results Results from the correlation analysis indicated that dietary cholesterol appeared a highly positive correlation (P＜0.05) with serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C).Data from the multiple regression analysis showed that dietary cholesterol intake was an important factor that affecting the serum TC (P＜0.05) in both males and females but LDL-C was only in females (P=0.01).After adjusting for potential confounders,the high intake of dietary cholesterol (≥300 mg/d) had higher risks for developing hypercholesterolemia in both males and females (OR=1.2 1,95％ CI:1.03-1.42,P=0.019;OR=1.18,95％CI:1.00-1.40,P=0.044),respectively.Conclusion Dietary cholesterol intake seemed to correlate with the serum cholesterol level,and hypercholesterolemia should be prevented through reducing the dietary cholesterol among Chinese adults.

Objective:To investigate the effect and associated mechanism of tumor tissue-infiltrating NK cells after receiving radiotherapy for hepatocellular carcinoma (HCC).Methods:A HCC tumor-bearing mouse model was constructed using human hepatocellular carcinoma cell line (SK-Hep-1) and divided into four groups: control, radiotherapy, NK cell clearance, and NK clearance combined with radiotherapy. Tumor growth condition was simultaneously recorded. The NK cell ratio in peripheral blood and the NK cell intratumoral infiltration condition were detected by flow cytometry and immunohistochemistry. Lentiviral-constructed SK-Hep-1 cells was used to detect the effect of radiotherapy on the regulation of CXCL10 and NK cell chemotaxis following EZH2 overexpression. SK-Hep-1 cells were irradiated in vitro and in vivo. The expression levels of EZH2 and CXCL10 mRNA and protein in the two groups of cell lines and mouse tumor tissues were detected by reverse transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), western blotting (WB), and immunohistochemistry. The chemotaxis and blocking experiments were used to validate the chemotaxis effect of CXCL10 on NK cells. The independent sample t-test was used to compare the groups. P<0.05 was considered statistically significant. Results:The HCC tumor-bearing mouse model experiment showed that HCC tumor growth was most remarkable in the NK clearance combined with the radiotherapy group compared to the radiotherapy group ( P<0.05). Compared with the control group, the number of NK cells in the peripheral blood of nude mice in the radiotherapy group was significantly reduced, while the NK cell intratumoral infiltration was significantly increased ( P<0.05). Flow cytometry and immunohistochemistry showed invitro and invivo expressional alterations. The average expression levels of EZH2 mRNA and protein in hepatocellular carcinoma cell lines and tumor tissues were decreased in the radiotherapy group than the control group and mouse tumor tissues ( P<0.05), while the mRNA and protein expression levels of CXCL10 increased ( P<0.05). The cell supernatant following radiotherapy enhanced NK cell chemotaxis but inhibited CXCL10 neutralization. EZH2 overexpression validated that radiotherapy up-regulated CXCL10 mRNA and down-regulated protein expression levels in in vitro and in vivo experiments ( P<0.05). The chemotactic effect on NK cells was significantly weakened with EZH2 overexpression following radiotherapy. Conclusion:NK cells, as immune effector cells, are directly involved in radiotherapy- activated anti-HCC immunity. Importantly, radiotherapy inhibits EZH2 expression in hepatocellular carcinoma, thereby upregulating CXCL10 expression and enhancing intratumoral NK cell invasion.

Objective:To investigate the morbidity of cerebrovascular disease among residents ≥30 years in Pengzhou, Sichuan Province, and analyze the effect of physical activity level on the risk of morbidity of cerebrovascular disease.Methods:From 2004 to 2008, people from Pengzhou, Sichuan Province were randomly selected. All the local people aged 30-79 were asked to receive a questionnaire survey, physical examination, and long-term follow-up to determine the morbidity of cerebrovascular disease. The physical activity level and the morbidity of cerebrovascular disease were described, and Cox proportional hazard regression models were used to evaluate the association of domain-specific physical activity with the risk of morbidity of cerebrovascular disease.Results:In 55 126 participants, there were 5 290 new cases of cerebrovascular disease, with a cumulative incidence of 9.60%. After the adjustment for multiple confounding factors, multivariate Cox proportional hazard regression analysis showed that increased levels of occupational, transportation, and total physical activity reduced the risk of cerebrovascular disease and its subtypes (cerebral hemorrhage, cerebral infarction). The highest group of occupational physical activity level had the lowest risk of cerebrovascular disease, with a hazard ratio ( HR) value of 0.81 (95% CI: 0.75-0.88), the highest group of transportation physical activity level had the lowest risk of cerebrovascular disease, with an HR value of 0.84 (95% CI: 0.78-0.91), the highest group of total physical activity level had the lowest risk of cerebrovascular disease, with an HR value of 0.87 (95% CI: 0.80-0.94), compared with the lowest group of corresponding physical activity. No association was found between the household/leisure-time physical activity level and the risk of cerebrovascular disease and its subtypes (cerebral hemorrhage, cerebral infarction). Conclusions:In project areas of Pengzhou, Sichuan Province, increased physical activity has been associated with reduced morbidity of cerebrovascular disease and its subtypes (cerebral hemorrhage, cerebral infarction). Increased levels of physical activity in adults are encouraged for health benefits.

Objective:To analyze the etiological distribution and phylogenetic characteristics of hand, foot and mouth disease (HFMD) in Qujing city of Yunnan Province in 2020.Methods:Stool samples were collected from HFMD cases in Qujing city in 2020 and virus RNA was extracted directly from treated stool suspensions. Virus VP4 gene sequences were firstly amplified using MD91/OL68-1 primer pairs and sequenced, then the virus serotypes were determined by BLAST search on the GenBank. Virus entire VP1 gene sequences were amplified and sequenced. Virus serotypes were identified online using Enterovirus Genotyping Tool Version 0.1. Sequences of reference virus genotypes/sub-genotypes were downloaded according to references. Phylogenetic trees were constructed by MEGA5.2 software and the genetic characteristics were analyzed.Results:A total of 47 strains of enteroviruses (EVs) were detected with a detection rate of 10.22% (47/460). The detected viruses were coxsackievirus A4 (CVA4, 0.65%, 3/460), CVA6 (7.83%, 36/460), CVA10 (0.87%, 4/460) and CVA16 (0.87%, 4/460). All were enterovirus species A (EVA), while other group viruses were not detected. The predominant virus was CVA6, accounting for 7.83% (36/460). EVA71 was not detected. CVA4 strains of C2 and C4 subgenotypes were co-circulating strains in Qujing city. CVA6 subgenotype D3a and CVA16 subgenotype B1a were also circulated in Qujing city. All CVA10 strains were in a separate lineage.Conclusions:Similar to the previous situation in China, the detection rates of EVA71 and CVA16 were very low, even zero. This study showed that CVA6 was the predominant virus, indicating a HFMD outbreak caused by CVA6 in Qujing city in 2020. The phylogenetic analysis showed CVA10 isolates belonged to a separate lineage, which might be unique to Qujing city. Laboratory and molecular epidemiological surveillance of non-EVA71 and non-CVA16 viruses, especially CVA6 and CVA10 should be strengthened in the future.

Objective:To investigate the changes of proopiomelanocortin(POMC) expression in hypothalamus and corresponding metabolism in miR-21 knockout mice.Methods:miR-21 knockout or wild-type C57BL/6J mice were divided into diabetic group and control group, respectively. Diabetic mice model were forged with high-fat diet and low-dose streptozotocin. The changes of body weight and blood glucose in each group were monitored. By the end of the experiment, mice were sacrificed, and POMC protein expression and STAT3 mRNA expression in hypothalamus were detected.Results:There were no significant differences in body weight and blood glucose levels among all groups at baseline( P>0.05). The differences of body weight and blood glucose levels among various groups were compared at 3, 6, 9 and 12 weeks after the model was established. The results showed that body weight of mice in the diabetes group or miR-21 knockout+ diabetes group was higher than that in the control group at each time point( P<0.05). Moreover, there were significant difference in body weight between diabetes group and miR-21 knockout+ diabetes group at 3 and 12 weeks( P<0.05). The blood glucose levels in diabetes group were significantly higher than those in other groups at each time point( P<0.05). The blood glucose level in miR-21 knockout+ diabetes group was lower than that in diabetes group and higher than control group( P<0.05). POMC protein and STAT3 mRNA levels in diabetes group were significantly lower than those in control group, while those in the miR-21 knockout+ diabetes group were higher than those in the diabetes group. Conclusions:The expression of POMC in hypothalamus of miR-21 knockout mice is higher than that of wild-type diabetic mice. miR-21 knockout can decrease blood glucose level and body weight, and improve energy metabolism of diabetic mice.

Objective: To investigate the possible mechanism of doxycycline inhibiting paraquat-induced pulmonary fibrosis and provide a theoretical basis for its clinical application. Methods: Human lung fibroblast HFL1 cells were selected as the research object in the cell group. Divided into blank group, paraquat group, paraquat+doxycycline group. The expression of TGF-β1, a-SMA, Smad3 and Smad2 protein was detected by ELISA using 40 ml of paraquat 40 umol/L and 3 mg/L of oleic acid 10 mg/L. In the animal group, 120 healthy and clean SD rats were randomly divided into three groups: blank group, paraquat group, paraquat+doxycycline group. The expression of TGF-β1, a-SMA, Smad3 and Smad2 protein in lung tissue of mice at 1 day, 3 days, 7 days, 14 days and 21 days was detected by Elisa method. The expression of TGF-β1, a-SMA, Smad3 and Smad2 protein in lung tissue of 21-day mice was detected by Western Blotting. The pathological changes of lung tissue were observed by HE staining for 1 day, 3 days, 7 days, 14 days and 21 days. Results: In the cell group experiment, the expression of TGF-β1, a-SMA, Smad3 and Smad2 protein increased gradually with paraquat in the paraquat group, and the expression of TGF-β1, a-SMA, Smad3 and Smad2 protein was significantly higher than that in the blank group. The difference was statistically significant (P<0.05) . The expressions of TGF-β1, a-SMA, Smad3 and Smad2 in the paraquat+doxycycline group were significantly lower than those in the paraquat group, but still higher than the blank group, the difference was statistically significant (P<0.05) . Conclusion Doxycycline inhibits paraquat-induced pulmonary fibrosis by inhibiting the expression of TGF-β1, a-SMA and Smad3, Smad2 proteins.

Objective: To analyze the status of dietary sodium intake of Chinese adult residents in fifteen provinces in 2015. Methods: Data were collected from 2015 China Nutrition Transition Cohort Study. This cohort study used a three consecutive 24-h retrospective method to record food intake and weighing method to record household condiment consumption. In this study, 14 847 residents aged 18 years and over with complete data from 15 provinces in 2015 were selected for the comparison of dietary sodium intake (median) with different characteristics. Results: Among the 14 847 residents, 47.1% were males, and the rural and northern residents accounted for 60.1% and 37.7%, respectively. Median sodium intake was 3 960.0 mg/d among residents in 2015. The sodium intake of males (4 272.1 mg/d) was higher than that of females (3 716.6 mg/d). Across age subgroups, sodium intake was highest among residents aged 45-59 years (4 257.0 mg/d; 18-44 years old, 3 867.1 mg/d; ≥60 years old, 3 799.0 mg/d). Sodium intake was higher in rural area (4 042.9 mg/d) than in urban area (3 866.8 mg/d), higher in north (4 229.2 mg/d) than in south (3 806.8 mg/d) (all P values <0.05). 11.8% of residents with dietary sodium intake were below 2 000 mg/d. The main sources of dietary sodium were condiments (79.4%), regular cooking foods (11.9%) and processed foods (8.7%). Among the condiments, the salt and soy sauce accounted for 63.6% and 10.4%, respectively. Conclusion In 2015, Chinese adult residents had higher dietary sodium intake with gender and regional differences. Condiments were the main source of dietary sodium.