Objective： To explore the DNA methylation sites correlated with blood pressure (systolic blood pressure, diastolic blood pressure, mean arterial pressure, pulse pressure) in adult twin population. Methods: A total of 476 twins from the Chinese National Twin Registry were selected as the research population. Questionnaires were used to collect demographic characteristics, lifestyle, disease status and other information, and blood pressure, height, weight and other anthropometric indicators were measured. The genome-wide DNA methylation of whole blood samples was detected by using Infinium HumanMethylation450 BeadChip. The DNA methylation sites correlated with blood pressure were analyzed by constructing mixed effect model with adjusting potential confounding factors, and the significant level was false discovery rate <0.05. Results: After data quality control, 465 twins (122 pairs of monozygotic twins, 104 pairs of dizygotic twins, 13 individuals from 13 pairs of twins) aged (44.8±13.2) years were finally enrolled. There were more males and more monozygotic twins, and the current smokers and current regular drinkers both accounted for more than 30%. No significant CpG site was found after multiple testing in the correlation study between genome-wide DNA methylation and blood pressure by using the collected twins. However, the cg07761116 located on chromosome 10 had low P value in the correlation analysis of 3 blood pressure indices (systolic blood pressure, diastolic blood pressure, mean arterial pressure), suggesting that this site might be correlated with blood pressure. The other 7 sites had low P value in the correlation analysis of the two blood pressure indices, respectively, which pointed to genes involved in neurological development, protein homeostasis, inflammatory reaction and other pathways. Conclusion: There is no sufficient evidence to support any DNA methylation site correlated with blood pressure, which may be caused by insufficient sample size and other reasons. This study could provide a reference for subsequent similar twin studies, and subsequent studies can focus on the cg07761116 located on chromosome 10 and other sites with low P values.

Objective： To compare the effects of different sized titanium dioxide (titanium dioxide, TiO2) on the antioxidant function of liver tissues in mice, and study the effect of TiO2 nanoparticles on the susceptibility of lipopolysaccharide (LPS) on liver tissues. Methods: Ninety 4-week-old clean-grade male ICR mice were divided into 18 groups, in which the mice were fed for different feed involving ordinary feed, nanometer TiO2 feed which meant the feed including 1% (mass fraction) TiO2 nanoparticles, and submicron TiO2 feed which meant the feed including 1% (mass fraction) TiO2 submicron particles. Respectively, they were fed for 1 month, 3 months and 6 months. On the second day after the feeding, respectively, 0 and 10 mg/kg LPS were given by gavage. The mice were harvested after 4 h and the body weight and liver weight for calculating the liver coefficient were recorded. Then the liver tissue homogenates were prepared for determining the antioxidant indexes including the total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-PX), and malondialdehyde (MDA). Results: The change of body weight in mice was only discovered in group fed for 1 month, which showed significant decrease of body weight in treatment groups compared with control group. And there was no significant change of the liver coefficient in each group. Compared with control groups, nanometer TiO2 groups and submicron TiO2 group, the activity of T-AOC, T-SOD and MDA of nanometer TiO2+LPS group and submicron TiO2+LPS group in which the mice were fed for 1 month and 6 months increased in different degree. And another result was also existing. The MDA activity of liver in different sized treatment groups fed for 3 months decreased. Neither significant difference between the results of different sized TiO2 treatment groups, nor significant difference among different sized TiO2 groups and the control groups were observed. Conclusion: Long-term peroral TiO2 nanoparticles and TiO2 submicron particles are more likely to cause damage to the liver in the growing mice, and the damage may be either reductive or oxidative. In addition, small sized TiO2 can increase the susceptibility of mice liver to LPS and the susceptibility will increase with the increase of exposure time.

Objective： To investigate effects of benzo(a)pyrene (BaP) on expressions of insulin-degrading enzyme (IDE) and neprilysin (NEP) which have the ability to degrade β-amyloid (Aβ) in neu-roglia cells. Methods: Primary mix-neuroglia cells were cultured from newborn SD rats. After exposure to BaP, Aβ1-42 oligomer or Aβ1-42 fiber individually or jointly for 24 h, the cell survival rate was mea-sured by cell counting kit-8 (CCK-8). Afterwards, the primary mix-neuroglia cells were divided randomly into six groups: Control group, BaP group (2.00 μmol/L), Aβ1-42 oligomer group (20.00 mg/L), BaP plus Aβ1-42 oligomer group, Aβ1-42 fiber group (20.00 mg/L) and BaP plus Aβ1-42 fiber group, of which BaP was pretreated for 12 h followed by cotreatment with different aggregated Aβ1-42. The expressions of IDE and NEP were measured by quantitative real-time polymerase chain reaction (qRT-PCR) for mRNA level and Western blotting for protein level. Results： The cell survival rate showed no significant differences after treatment with BaP (≤20.00 μmol/L), Aβ1-42 oligomer (20.00, 40.00 mg/L), Aβ1-42 fiber (20.00, 40.00 mg/L) or cotreatment with BaP and Aβ1-42 oligomer or BaP and Aβ1-42 fiber. Compared with the control group, expressions of IDE and NEP in BaPtreated alone group had no obvious change; however, exposure to Aβ1-42 oligomer alone significantly increased the mRNA and protein level of IDE (P<0.05), and the BaP pretreatment could significantly inhibit the up-regulated expressions of IDE by Aβ1-42 oligomer (P<0.05); on the other hand, exposure either to Aβ1-42 fiber alone or under the BaP pretreatment did not change the mRNA and protein level of IDE and NEP obviously. Conclusion: On the premise of no significant change of cell survival rate, BaP pretreatment inhibited the up-regulated expressions of IDE in primary mixed neuroglia cells under cotreatment with Aβ oligomer, indicating that BaP may disturb degradation of Aβ oligomer and cause deposition of β-amyloid and further induce cognitive decline and acceleration of Alzheimer.

Objective： To evaluate the comprehensive technical efficiency of the tertiary public hospitals in Beijing between 2006 and 2015 and explore its influencing factors, so as to propose corresponding policy suggestions. Methods: The data envelopment analysis was employed to evaluate the comprehensive technical efficiency, pure technical efficiency and scale efficiency of the tertiary public hospitals in Beijing. Malmquist index model was used to analyze the changes of the above three dynamic efficiencies. Finally, random-effect panel tobit model was utilized to analyze the influencing factors of the comprehensive technical efficiency. Results: The average comprehensive technical efficiency and pure technical efficiency of the tertiary public hospitals in Beijing were relatively high, and they had respectively increased from 0.44 and 0.51 in 2006 to 0.62 and 0.68 in 2015, and the highest proportion of two kinds of efficiency values was between 0.5 and 0.8. Most of the scale efficiency values distributed between 0.8 and 1.0, and the majority of hospitals were in a state of decreasing returns to scale. The total factor productivity of hospitals had been increasing at an average rate of 5.78% per year due to the double progress of technical efficiency and technology at annual rates of 3.77% and 1.94% respectively, further decomposing technological efficiency change, and the pure technical efficiency change increased at the speed of 3.21% per year, and the annual average rate of progress in scale efficiency was only 0.53%. The comprehensive technical efficiency was positively correlated with the turnover rate of beds, annual visits per doctor, the ratio of doctors to nurses, and negatively correlated with the number of beds, the ratio of outpatients to inpatients, the proportion of medical technical personnel, and the proportion of drugs. Conclusion: Future health policies should strictly control the scale of tertiary public hospitals, pay attention to the innovation and application of hospital technology, change the hospital internal management le-vel and management model, promote refined management, and achieve sustainable development.

Objective： To estimate the incidence rate and effects of risk factors on chronic kidney di-sease (CKD) in Chinese patients with diabetes, based on Electronic Health Records (EHRs) from the Chinese Electronic health Records Research in Yinzhou (CHERRY) Study. Methods: Using the CHERRY cohort study with the individual-level information on chronic disease management; and health administrative, clinical and laboratory databases, patients with diabetes without kidney disease at baseline were enrolled and followed up from January 2009 through December 2016. CKD was defined as the estimated glomerular filtration rate(eGFR) <60 mL/(min×1.73 m2) or urine albumin/creatinine ratio (ACR)≥3 mg/mmol. Standardized incidence rates of CKD in diabetic population were calculated according to the 2010 China census data. Cox proportional hazards models were used to explore the association of risk factors on CKD in patients with diabetes. Results: Over a median 3.2 years of follow-up, 13 829 patients with diabetes were included in this analysis and 1 087 developed CKD. The crude and standardized incidence rate was 23.7(95%CI: 22.3-25.2) and 14.8(95%CI:12.1-17.6) per 1 000 personyears respectively. The incidence rate for developing CKD in patients with diabetes aged over 60 years was higher than those aged 60 and below(26.6 vs. 11.5 per 1 000 person-years, P<0.05).Cox proportional hazards models showed that age over 60 years(HR=1.88, 95%CI:1.51-2.35), hypertension(HR=1.81, 95%CI:1.56-2.10), total cholesterol (HR=1.07, 95% CI:1.00-1.14) and duration of diabetes (HR per year increment=1.02,95%CI:1.00-1.03)and the level of high density lipoprotein cholesterol (HDLC, HR=0.49,95%CI:0.40-0.61) were significantly associated with CKD. No statistical significance was found for sex, smoking status, alcohol use and average level of fasting glucose (All P>0.05).Subgroup analysis indicated that even when the lipid levels were well-controlled, comorbidity of hypertension was still associated with CKD in the patients with diabetes. Conclusion: Incidence rate of chronic kidney disease in this Chinese population with diabetes was high. Age and comorbidity of hypertension were the most important risk factors for CKD, suggesting the priority for CKD screening in patients with diabetes in China. Control of blood pressure and lipid were especially crucial to prevent CKD in patients with diabetes.

Objective： To analyze the epidemic situation of blood pressure (BP) status and its association with nutritional status among Chinese children and adolescents aged 7－18 years old in 2014, and to provide important scientific basis for the control of students’ hypertension. Methods: All the subjects aged 7 to 18 years in both genders were sampled from 2014 Chinese national surveys on students’ constitution and health. BP status was evaluated according to Chinese national gender-, age-and height-specific references, including hypertension (HTN), elevated hypertension (elevated HTN), isolated systolic HTN (SHTN), isolated diastolic HTN (DHTN) and mix HTN. Their nutritional status was evaluated using the international obesity task force (IOTF) definition, including thinness (severe thinness and moderate thinness), normal, overweight and obesity (severe obesity and moderate obesity). The Logistics method was used to analyze the association between BP status and nutritional status. The population attributable risk (PAR%) of overweight and obesity for BP status was calculated. Results: The prevalence of HTN and elevated HTN among the Chinese children and adolescents aged 7－18 years in 2014 was 14.9% and 9.2%, respectively. And the prevalence of isolated SHTN, isolated DHTN and mix HTN was 3.1%, 8.8% and 3.0%, respectively. The prevalence estimates for HTN differed the greatest for the boys, those in rural, those with high age, those in the East, and those with high BMI. The highest prevalence of HTN was detected in those with severe obesity with 44.2% and 38.8% in the boys and girls respectively, which was 2.8-fold and 3.7-fold than those with normal groups. The negative association was detected between HTN and thinness, but the positive association with overweight and obesity. The PAR% of HTN due to overweight and obesity was 16.2%, and the expected prevalence of HTN was 12.5% if controlling for overweight and obesity. Higher PAR% of isolated SHTN and mix HTN due to overweight and obesity was detected in the Chinese children and adolescents with proportions of 28.7% and 35.1%. Conclusion: The prevalence of HTN among the Chinese children and adolescents aged 7－18 years was still high, whose components mainly focused on isolated DHTN. Overweight and obesity can increase the risk of HTN in children and adolescents significantly, especially for isolated SHTN and mix HTN. Controlling for overweight and obesity can decrease the risk of HTN among Chinese national children and adolescents largely, which can play an important role in preventing the occurrence of chronic disease in adults.

Objective： To analyze the association between sleep duration and athletic performance, and provide scientific basis to improve the 50 m and endurance performance in children and adolescents. Methods： All the 119 462 subjects aged 9-15 years in both genders were sampled from 2014 National Physical Fitness and Health Surveillance by using stratified random cluster sampling method, to measure the height, weight, 50 meters and endurance performance and investigate sleep duration with questionnaire. Their body mass indexes (BMI) were calculated and the students’ 50 m, endurance run scores and sleep durations were assessed. Binary Logistic regression was used to analyze the difference between the different sleep groups, and multi-factor Logistic regression was used to analyze the relationship between the sleep condition and athletic performance. Results： The prevalence of insufficient sleep was 94.67% in the total subjects, the prevalence was higher among the girls (95.26%)than the boys (94.09%, χ2=80.99, P<0.001), and higher among the urban (95.41%) than the rural students(93.93%, χ2=128.48, P<0.001).The children with sufficient sleep had better performance in 50 m and endurance run scores( χ2 50 m=10.10, P50 m＜0.01; χ2endurance run=21.76, P<0.001）. Logistic regression analysis after controlling the gender, area, grade and BMI showed that children with adequate sleep showed better results(OR50 m=1.14, 95% CI50 m=1.05-1.23, P50 m<0.01; ORendurance run=1.21, 95% CIendurance run=1.11-1.31, Pendurance run<0.001）. As for gender, the excellent rates of 50 m and endurance run scores in the boys with adequate sleep were higher (P<0.001), but there were no signi-ficant difference in 50 m and endurance run excellent rates in the girls of different sleep conditions. The excellent rates of 50 m and endurance run in the urban children and the endurance rate in the rural children and adolescents with adequate sleep were higher than those with insufficient sleep (P<0.01) while there were no significant difference in the 50 m excellent rates between the different sleep groups in rural areas. The 50 m and endurance run excellent rates of the children and adolescents with adequate sleep in each grade were higher than those of the children in the same grade with insufficient sleep (Pprimary students’ endurance performance<0.001, and the rest P<0.05). Children and adolescents with normal BMI and overweight who slept well had better performance in 50 m (P<0.05). The endurance run excellent rate of children and adolescents with adequate sleep in each BMI group was higher than that in children and adolescents with insufficient sleep in the same BMI group (Pmalnutrition<0.01, Pnormal<0.01, Poverweight<0.05, Pobesity<0.05). The children and adolescents were divided into different groups according to the sleep duration，the one who slept less than 7 hours had lower 50 m excellent rate than the other groups with longer sleeping duration (P<0.01) and the rate in the ones who slept more than 9 hours was the highest (P<0.001).The endurance excellent rate in the children and adolescents who slept more than 9 hours was significantly higher than that in the other groups (P<0.001).There was no significant dose-response relationship in excellent rates and sleep durations. Conclusion： The prevalence of insufficient sleep has increased, and the sleep condition in children and adolescents is severe. Children and adole-scents with sufficient sleep have better athletic performance, so we should strengthen the prevention and control of the lack of sleep in children and adolescents.

Objective： To analyze the situation of physical fitness among Chinese Han students in 2014, so as to develop the guideline of physical activity regarding to the targeted students and to provide bases for the improvements of students’ physical fitness. Methods: Subjects were from 2014 Chinese National Surveys on Students’ Constitution and Health (CNSSCH). In this survey, 212 401 Han students aged 7-18 years participated and the measurement of physical fitness completed. The qualified rates of indicators regarding to physical fitness were evaluated based on “National Students Constitutional Health Standards” (2014 revised edition). Logistic regression was used to assess the association between the indicators of pull ups (boys) and endurance run (boys and girls) and influencing factors. Results: In 2014, among the boys, the qualified rates of pull ups and endurance run were 18.7% and 76.6% respectively, while the qualified rate of endurance run was 80.6% among the girls. These two indicators were the weak items of physical fitness among the Chinese Han students. There was regional difference in the qualified rates of physical fitness, and the students in Zhejiang and Jiangsu provinces had higher qualified rates. Logistic regression showed that the urban students (OR=0.67), the students with malnutrition (OR=0.76), overweight (OR=0.32) or obesity (OR=0.12) were less likely to be qualified to pull ups; the students who had physical activity more than 1 h per day (OR=1.31) was more likely to be qualified to pull ups. The influencing factors of endurance run showed the similar pattern, in addition, the students with enough physical education (PE) were more likely to be qualified to endurance run, while the students with “Squeeze” or “no” PE class were less likely to be qualified to endurance run. Conclusion: The pull ups and endurance run have become the weak items of the physical fitness among primary and secondary school students in our national and provincial levels. Based on ensuring physical exercise time and PE curriculum and class hours, as well as improving students’ nutrition, we should also strengthen the rational design of physical exercise and ensure the balanced development of various items so as to improve the overall development of students’ physical fitness.

Objective： To estimate the potential health benefit of screening strategies for cardiovascular diseases primary prevention in a rural northern Chinese population. Methods: A total of 6 221 adults aged 40-74 years old, from rural Beijing, China and free from cardiovascular diseases at baseline were included. The following screening strategies were compared: Strategy 1, the strategy based on numbers of risk factors recommended by the Chinese Guideline for Prevention of Cardiovascular Diseases in people aged 40-74; Strategy 2, screening people aged 40-74 based on the Prediction for Atherosclerotic Cardiovascular Disease Risk in China (China-PAR) risk prediction model; Strategy 3, screening people aged 50-74 using the China-PAR risk prediction model. Participates who were classified into medium- or highrisk by the correspond-ing strategies would be introduced to lifestyle intervention, while high risk population would take medi-cation in addition. Markov model was used to compare the potential health benefits within 10 years in each scenario, which applied the parameters from this rural northern Chinese cohort, published literatures, meta-analyses and systematic reviews, clinical trials and other cohort stu-dies of Chinese population. Quality-adjusted life year (QALY) gained, cardiovascular diseases (CVD) events/deaths could be prevented and number needed to be screened (NNS) per QALY gained/per CVD event prevented/per CVD death prevented were calculated to compare the effectiveness. One-way sensitivity analysis concerning uncertainty of cardiovascular disease incidence rate and probabilistic sensitivity analysis about the uncertainty of hazard ratios were conducted. Results: Compared with non-screening strategy, the potential health benefits of each strategy were: Strategy 1 would gain QALY of 498 (95%CI: 103-894) and prevent 298 (95%CI: 155-441) CVD events; Strategy 2 would gain QALY of 691 (95%CI: 233-1 149) and prevent CVD events of 374 (95%CI: 181-567); Strategy 3 would gain QALY of 654 (95%CI: 199-1 108) and prevent CVD events of 346 (95%CI: 154-538). Screening strategy based on China-PAR risk prediction model (strategy 2 or 3) would be generally better in terms of QALY gained, CVD events/deaths prevented and NNS than the strategy based on numbers of CVD risk factors (all P<0.05 except NNS per QALY gained and NNS per CVD event prevented in 40-74 years). Similar benefits were obtained for the strategy 2 and 3. The results were consistent in the sensitivity analyses on the parameters of incidence rates and hazard ratios. Conclusion: Screening people to target increased risks of cardiovascular diseases in this rural northern Chinese population is necessary. Screening strategy based on China-PAR risk prediction model could gain more health benefits than that based on numbers of CVD risk factors.

Objective： To explore the influencing factors of elderly outpatient visits and to provide evidence for poverty reduction in health in the poor rural areas. Methods: Through stratified sampling, a total of 1 271 aged people in four poverty Qi/County of Ulanqabcity were surveyed, including Qahar Right Wing Front Banner, Qahar Right Wing Middle Banner, Qahar Right Wing Rear Banner and Liangcheng County. Their socio-economic and demographic characteristics, daily consumption, EuroQol five dimensions questionnaire(EQ5D) and visual analogue scale(VAS),social support, health service needs and utilization were collected through cross-sectional household questionnaires. 1 039 aged people who had experienced physical discomfort in the past 30 days were selected as subjects for the study. The differences between the groups were analyzed by chi-square test. A Logistic regression equation and a decision tree of elderly visits were built to find factors influencing decision-making of the aged. Results: The average age of the research subjects was 71.8 years, with 52.2% being illiterate and 85.8% with middle social support. 58.5% of the subjects living with their spouses, mostly living in 15 min medical circle and without any financial support from their children. The 30-day visiting rate when having physical discomfort was 31.0%. The chi-square test showed that the differences in visit rates among age, ethnic, residence patterns, daily consumption index, housing types, social support scores, grown children’s economic assistance, travel time to medical institutions, and health self-assessment scores were statistically significant. Compared with Logistic analysis, the decision tree showed lower error rate of classification. Logistic regression model’s error rate of classification was 31.4%,showing that the differences in visit rates among age, ethnic, residence patterns, daily consumption index, social support scores, travel time to medical institutions, and health self-assessment scores were statistically significant. The decision tree model’s error rate of classification was 28.6%, showing six main influencing factors, including the travel time to medical institutions, cohabitants, education level, age, whether adult children provide economic support and social support score. The importance of these predictors were 0.42, 0.21, 0.13, 0.11, 0.07 and 0.06, respectively. Conclusion: In poor rural areas, medical resources, economic affordability, family and individual socio-demographic characteristics are the key factors affecting decision-making for the aged. It is necessary to integrate the improvement of the health care of the aged into the overall development of the society. And comprehensive interventions should be adopted to improve the outpatient utilization for aged in poor rural areas.

Objective： To investigate the current situation of the activities of daily living (ADL) of the aged at home in western China, and to analyze its influencing factors so that we can improve the quality of life and pension services of elderly people. Methods: The elderly people who came from Qinghai Pro-vince, Ningxia Autonomous Region, Xinjiang Uygur Autonomous Region, Shanxi Province, Guizhou Pro-vince, Guangxi Province, Sichuan Province, Yunnan Province and Chongqing were surveyed by questionnaires. Logistic regression model was used to analyze the influencing factors of ADL. Results: A total of 7 175 aged people living in the western China were surveyed. In the study, 78.86% of the aged at home could independently live. 12.32% of the aged were of mild dysfunction. 6.27% of the aged had mode-rate dysfunction. And 2.55% of the aged suffered severe dysfunction. Multiple Logistic analyses indicated that age, educational level, economic income, body mass index and disease were the factors that affected their ADL. The risk of decreased ADL in the 60-69 and 70-79year-old groups were 0.221 (95%CI: 0.190-0.258) and 0.353 (95%CI: 0.305-0.409) times that of the elderly over the age of 80. Compared with illiterate seniors，the risks of decline in ADL of primary school, junior high school, secondary or high school, college or undergraduates, postgraduates or above were 0.299 (95%CI: 0.140-0.637), 0.312 (95%CI: 0.146-0.663), 0.238 (95%CI: 0.112-0.510), 0.226 (95%CI: 0.105-0.484), and 0.238 (95%CI: 0.110-0.514) times. The declines in the risk of ADL for elderly people with quite difficult economic conditions, slight difficulty and breaking even were 2.720 (95%CI: 2.015-3.672), 2.344 (95%CI: 1.816-3.027), and 1.542 (95%CI: 1.215-1.957) times of the economically abundant people. Compared with those with a body mass index (BMI)≥28, the risk of ADL reduction for BMI<18.5 was 1.577 (95%CI: 1.142-2.179) times. And the ADL of the elderly with no disease was at the risk of falling 0.685 (95%CI: 0.602-0.779) times that of an elderly person with the disease. Conclusion: The activities of daily living of age at home of western China are not high, and affected by many factors, such as age, educational level and so on. With the increasing of the elderly, maintaining and improving the ADL are the problems and challenges that we are faced with.

Objective： To explore the levels of blood manganese concentration in pregnant women in 1st and 2nd trimester and the associated factors in three counties of northern China. Methods: We carried out a crosssectional investigation in three counties of northern China in 2010. Two hundred and seventy three pregnant women whose gestational age was less than 28 weeks were recruited, their demographic characteristics and information on exposure to indoor air pollution from coal combustion and dietary during one month before pregnancy till the date of investigation were collected with questionnaires by face-to-face interview, their fasting venous whole blood samples were collected with vacuum blood collection tube containing heparin lithium at the Maternal and Child Health Hospital in the three counties. Their blood manganese concentrations were measured with inductively coupled plasma mass spectrometry (ICP-MS). Nonparametric tests were used to compare the concentrations among the groups and multivariate unconditional Logistic regression model was used to adjust the confounding factors. Results: The geometric mean of blood manganese of the women was 16.78 (95%CI: 16.14－17.45) μg/L, and the median (interquartile range) was 16.59 (13.68－20.44) μg/L. According to the reference range of general healthy adult female’s manganese concentration in the whole blood 3.39－20.67 μg/L, the proportion of manganese concentration lower than normal, normal, higher than normal were 0%, 76.6% and 23.4%, respectively. Medians of blood manganese concentrations among the women in Yushe, Dai and Xianghe were 17.51 (13.96－22.04), 16.92 (13.78－21.45) and 15.43 (12.25－17.56) μg/L, respectively (P<0.05), and multivariate analysis found that the risk of higher than normal in Yushe County was 6.15 (95%CI: 1.21－31.35) times the risk in Xianghe county. Blood manganese concentrations were higher in women who were farmers, had lower income per month, and consumed more vinegar and less peppers, pork, beef and mutton during the month before investigation (all P<0.05), the adjusted odds ratio (AOR) between these factors and high blood manganese concentration were not statistically significant No statistical associations were found between blood manganese levels and indoor air pollution from coal combustion for both of crude odds ratrio (COR) and AOR (P>0.05). Conclusion: The blood manganese concentration among pregnant women in the three counties is similar to the women in some other studies abroad and quite different from the findings of several domestic researches. The risk of blood manganese concentration higher than normal in Yushe county was higher than Xianghe county. The relationships between high manganese concentration and exposure to indoor air pollution from coal combustion or dietary need further research in the future.

Objective： To explore the relationship between sugary drinks and diabetes of adults in Wuhai city. Methods: A multiple stage stratified cluster sampling was conducted on 8 131 residents who were between 35 and 79 years by cross-sectional study in Wuhai city. Questionnaires, physical measurements and laboratory tests were used to collect information on demographic information, dietary behavior, health status, blood glucose indicators. Besides, other covariate information was also collected by these ways. The analysis was carried out by chi-square test, trend chi-square test and multifactor Logistic regression. Results: The detection rates of impaired fasting glucose and diabetes of people who were 35 years old and above in Wuhai city were 6.0% and 18.4%, respectively, and they both increased with age (P<0.01, P< 0.01). The detection rates of impaired fasting glucose and diabetes of the men were both far higher than the women (P< 0.01, P< 0.01). For the men, the detection rate of diabetes increased with age (Ptrend <0.01), but for the women, and the detection rate of impaired fasting glucose and diabetes both increased with age (Ptrend <0.01, Ptrend <0.01). The consumption rate of sugary drinks of the people who were 35 years old and above in Wuhai city was 30.2%. And after all the subjects were classified into three groups, A (0－ mL/d), B (16－ mL/d), and C (237－ mL/d) accor-ding to the daily different drinking quantities, statistical results found that group A accounted for 75.4%, group B for 21.5%, and group C for 3.1%. In group A, for comparison, the impaired fasting glucose OR values of group B and group C were 1.4 and 2.2, respectively. And diabetes OR values of group B and group C were 1.2 and 2.1 respectively compared with group A, and the trend of OR values increased both had statistical significance (Ptrend <0.01, Ptrend < 0.01). Also, after adjusting for other covariates in multifactor Logistic regression, the OR values of impaired fasting glucose in group B and group C were 1.6 and 3.8 respectively, and the OR values of diabetes were 1.9 and 4.9 respectively, compared with group A, and besides, the trend of OR values increased both still had statistical significance (Ptrend <0.01, Ptrend < 0.01). Conclusion: Increased consumption of sugary drinks will increase the risk of impaired fasting glucose and diabetes. Residents in Wuhai city should control their consumption of sugary drinks.

Objective： To provide autonomy support from three dimensions based on self-determination theory (SDT), i.e. professional support, peer support, family support, and to investigate whether this intervention can improve diabetes self-management behavior and glycemic control of diabetic patients, and to analyze the influencing factors of the effect. Methods: Using convenient sampling method, three communities were selected respectively in Beijing. Each community selected health service stations with similar conditions as different intervention groups. The diabetic patients managed by the station who were eligible for inclusion were recruited into this intervention group. The community stations were divided into three groups. The routine intervention group only issued knowledge manuals and conducted health ma-nagement according to the requirements of basic public health services. Peer support groups were divided into small groups and carried out doctorled group activities. Based on doctor-led peer support activities, the doctors and peers were trained to provide autonomy support based on self-determination theory, and their family members were trained in the form of manuals to provide autonomy support, forming a concerted support of the three dimensions. Activity processes and materials were also designed based on SDT. The intervention duration was 3 months, and the main evaluation indexes were HbA1c and patients’ self-management behaviors, skills, knowledge, and self-efficacy scores. Results: Before and after the intervention, the HbA1c of routine intervention group were 7.40%±1.37%, 7.30%±1.18%. The HbA1c of peer support group before and after the intervention were 7.33%±1.15% and 7.13%±1.27%. The HbA1c of autonomy support group before and after the intervention were 7.42%±1.22% and 6.78%±0.80%. Before and after the intervention, the self-management score in routine intervention group was 10.54±2.28 and 10.80±2.15, the score in peer support group was 11.09±1.89 and 11.40±1.78, the score in autonomy support group was 10.34±1.99 and 11.10±1.65, respectively. The HbA1c and self-management score increased higher in autonomy support group than in the other two groups. After intervention, the control rate in autonomy support group was higher than in the other two groups. According to the multi-factor analysis, the value of HbA1c after intervention was positively related to the baseline HbA1c, and negatively related to self-management behavior. The value in autonomy support group was higher than in routine intervention group. Baseline self-management behavior, self-efficacy, knowledge, skill, family support, autonomy support, peer support and age were positively correlated with the change of behavior. Conclusion: Self-management behavior intervention based on selfdetermination theory can effectively promote selfmanagement behavior and glycemic control of diabetic patients, and the effect is better than single peer support activities.

Objective： To analyze the effect of domestic high-efficiency particulate air (HEPA) puri-fiers on the concentrations of indoor fine particulate matter (PM2.5) and its elementary constituents in 20 residences in a district of Beijing during winter. Methods: From November 2015 to January 2016, 20 residences in a district of Beijing were selected, where indoor and outdoor PM2.5 data were collected simultaneously in three time periods according to the operating of air purifiers (Group 0 h: 24 hours before operating; Group 24 h: 24 hours after operating; Group 48 h: 24 to 48 hours after operating). The content of 21 elements in PM2.5 samples were determined by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICPOES). Indoor/outdoor particle concentration ratio (I/O ratios) and ΔI/O ratios were used to describe the pollution levels and the variation range of PM2.5 and its 21 elementary constituents. One-way analysis of variance (ANOVA) for repeated measurement data was applied to compare the I/O ratios of PM2.5 and its elementary constituents among the different groups, and Bonferroni method was used for comparison in pairs. Wilcoxon signed rank test for paired-samples was used to compare ΔI/O ratios of 21 elementary consti-tuents with that of PM2.5. Results: The median I/O ratios of PM2.5 in the three groups were 1.27 (P25-P75: 0.50-2.68), 0.45 (P25-P75: 0.27-1.03) and 0.36 (P25-P75: 0.28-2.48), respectively. Compared with Group 0 h, the I/O ratios of PM2.5 in Group 24 h (P=0.042) and Group 48 h (P=0.006) decreased significantly. However, there was no significant difference between Group 24 h and Group 48 h. Significant differences were found comparing ΔI/O ratios of aluminium, ferrum and titanium to that of PM2.5, in both Group 24 h and Group 48 h (P<0.05). No significant change was found in the I/O ratios of these three elements among the three groups before and after air purifier operating (P>0.05). Distances from residences to traffic arteries could affect I/O ratios of some elements from trafficrelated source (P<0.05). Conclusion: Domestic HEPA air purifiers could effectively reduce indoor PM2.5 concentration, and the pollution level of PM2.5 tend to be stable after the purifier operating for a time. The purifiers had different effects on different elements, among which most showed statistical significances.

Objective： To form a new assessment method to evaluate postural workload comprehensively analyzing the dynamic and static postural workload for workers during their work process to analyze the reliability and validity, and to study the relation between workers’ postural workload and work-related musculoskeletal disorders (WMSDs). Methods: In the study, 844 workers from electronic and railway vehicle manufacturing factories were selected as subjects investigated by using the China Musculoskeletal Questionnaire (CMQ) to form the postural workload comprehensive assessment method. The Cronbach’s α, cluster analysis and factor analysis were used to assess the reliability and validity of the new assessment method. Non-conditional Logistic regression was used to analyze the relation between workers’ postural workload and WMSDs. Results: Reliability of the assessment method for postural workload: internal consistency analysis results showed that Cronbach’s α was 0.934 and the results of split-half reliability indicated that Spearman-Brown coefficient was 0.881 and the correlation coefficient between the first part and the second was 0.787. Validity of the assessment method for postural workload: the results of cluster analysis indicated that square Euclidean distance between dynamic and static postural workload assessment in the same part or work posture was the shortest. The results of factor analysis showed that 2 components were extracted and the cumulative percentage of variance achieved 65.604%. The postural workload score of the different occupational workers showed significant difference (P<0.05) by covariance analysis. The results of non-conditional Logistic regression indicated that alcohol intake (OR = 2.141, 95%CI 1.337－3.428) and obesity (OR = 3.408, 95%CI 1.629－7.130) were risk factors for WMSDs. The risk for WMSDs would rise as workers’ postural workload rose (OR = 1.035, 95%CI 1.022－1.048). There was significant different risk for WMSDs in the different groups of workers distinguished by work type, gender and age. Female workers exhibited a higher prevalence for WMSDs (OR = 2.626, 95%CI 1.414－4.879) and workers between 30－40 years of age (OR=1.909, 95%CI 1.237－2.946) as compared with those under 30. Conclusion: This method for comprehensively assess-ing postural workload is reliable and effective when used in assembling workers, and there is certain relation between the postural workload and WMSDs.

Objective： To explore the association between anemia and cardiovascular disease and all-cause mortality among diabetic patients, and whether the association is modified by the presence of chro-nic kidney disease (CKD). Methods: Physical examination data of 8 563 patients with diabetes who met the inclusion and exclusion criteria between 2010 and 2011 were collected, based on the prospective cohort data of Kailuan study. The deadline of the follow-up was December 31, 2015, and the endpoints comprised all-cause mortality and cardiovascular disease. Survival analysis was performed by Kaplan-Meier method. Cox proportional hazards regression model was used to assess the association between anemia with or without CKD, and cardiovascular events and all-cause mortality after adjustment for confounding factors. Results: The average age of the subjects was (57.3±10.3) years, of whom the patients with anemia accounted for 5.2%. The proportion of the patients with anemia combined with CKD was higher than that of the patients without anemia (27.2% vs. 20.8%, P=0.001). The median follow-up time was 4.9 years (interquartile range: 4.6-5.2 years). During the follow-up period, 559 patients died, and 434 patients had cardiovascular disease. Compared with the patients without anemia, the all-cause mortality rate of the patients with anemia was higher (3 220.3/100 000 person-years vs. 1 257.9/100 000 person-years, P<0.001). There was no statistically significant difference in the incidence of cardiovascular disease between the above two groups (999.8/100 000 person-years vs. 1 081.2/100 000 person-years, P>0.05). The mortality and incidence of cardiovascular disease among the patients with CKD were higher than those of the patients without CKD (2 558.3/100 000 person-years vs. 1 044.0/100 000 person-years, P<0.001; 1 605.9/100 000 person-years vs. 941.6/100 000 person-years, P<0.001). Results of Cox regression model showed that, after adjustment for confounding factors, the all-cause mortality risk increased by 95% in the diabetic patients with anemia (HR=1.95, 95% CI: 1.50-2.54). Anemia and CKD significantly increased the mortality risk among diabetic patients (HR=3.61, 95% CI: 2.48-5.26). The CKD patients without anemia had an increased risk of cardiovascular disease (HR=1.41, 95% CI: 1.13-1.74). Conclusion: Anemia is associated with an increased mortality risk in Chinese diabetic patients. Patients with CKD have an increased risk of cardiovascular di-sease and mortality. The all-cause mortality risk increases significantly in anemia patients with the pre-sence of CKD, which indicates that we should focus on the prevention and treatment of diabetic patients with anemia and CKD.

Objective： To evaluate the correlation between nailfold capillaroscopic (NC) findings and the presence of interstitial lung disease (ILD) in systemic sclerosis (SSc) patients. Methods: We retrospectively involved 71 SSc patients, 45 patients with ILD. NC was performed in all the patients according to the standard method. The NC findings were semi-quantitatively scored, including enlarged and giant capillaries, hemorrhages, loss of capillaries, avascular areas, ramified/bushy capillaries and disorganization of the vascular array. The demographic and clinical data collected were gender, age, presence/absence of Raynaud phenomenon (RP), duration of RP, serological acute phase reactants and antibodies, presence of ILD (also evaluated the CT score for ILD) and pulmonary function parameters. Results: Among the 71 patients, the frequency of the women was 91.5%, the mean age was (52.59±12.77) years, and disease duration was (3.00±6.00) years. NC changes of the scleroderma pattern were observed in 90.1% patients. There were 45 patients with ILD and 26 patients without ILD. The patients with ILD had significantly higher loss of capillaries score ［0.50 (1.03) vs. 0.00 (0.43), P=0.003］, avascular area score ［0.75 (1.24) vs. 0.25 (0.83), P=0.006］ and ramified/bushy capillaries score ［0.33 (0.88) vs. 0.13 (0.25), P=0.006］ compared with those without ILD. Moreover, ramified/bushy capillaries score together with diffused SSc were independent risk factors for the presence of ILD. And the score of giant capillaries were significantly lower in the patients with more severe ILD group ［0.25 (0.94) vs. 0.00 (0.28), for the mild and severe ILD groups respectively, P=0.019］. There was no statistically significant difference between the two groups with respect to the scores of enlarged capillaries, hemorrhages, or disorganization of the vascular array. Conclusion: Capillary deletion and severe deformity in NC were associated with the presence of ILD in SSc patients. And patients with less giant capillaries had more severe ILD involvement. These indicated that NC maybe a useful tool to evaluate ILD in SSc.

Objective： To analyze the potential perioperative risk factors that affect the development of urosepsis following percutaneous nephrolithotomy (PCNL) for upper urinary tract calculi with a regression model, and to develop a nomogram for predicting the probability of postoperative urosepsis after PCNL according to the identified independent risk factors. Methods: We retrospectively analyzed the clinical data from consecutive 405 cases of upper urinary tract calculi treated by one-phase PCNL between January 2013 and December 2016 in our clinical department. According to whether the patients developed urosepsis or not after the surgery, the patients were divided into two groups. Perioperative risk factors that could potentially contribute to urosepsis were compared between the two groups. By a Logistic regression model, univariate and multivariate statistical analyses were carried out for the occurrence of postoperative urosepsis, to identify the independent risk factors affecting the development of postoperative urosepsis. From this model, a nomogram was built based on regression coefficients. Results: The PCNL procedures of the 405 cases were performed successfully, and there were 32 cases that developed urosepsis after the PCNL, and the incidence of urosepsis was 7.9% (32/405). A multivariate Logistic regression model was built, excluding the factors with values of P>0.05 in the univariate analysis. Multivariable Logistic regression analysis identified the following factors as independent risk factors for urosepsis after PCNL: diabetes mellitus history (OR=4.511, P=0.001), larger stone burden (OR=2.588, P=0.043), longer operation time (OR=2.353, P=0.036), increased irrigation rate (OR=5.862, P<0.001), and infectious stone composition (OR=2.677, P=0.036). The nomogram based on these results was well fitted to predict a probability, and the concordance index (C-index) was 0.834 in the nomogram model sample and 0.802 in the validation sample. Conclusion: Diabetes mellitus history, higher stone burden, longer operation time, increased intraoperative irrigation rate, and infectious stone composition are identified as independent risk factors to affect the development of urosepsis after one-phase percutaneous nephrolithotomy for upper urinary tract calculi. A nomogram based on these perioperative clinical independent risk factors for urosepsis could be used to predict the risk of urosepsis following PCNL.

Objective： To investigate the level and influencing factors of health-related quality of life in myasthenia gravis (MG) patients with myasthenia gravis quality of life-15 (MGQOL-15) Chinese version and to provide corresponding measures in one tertiary hospital of Sichuan Province. Methods: We collected the general data (gender, age, body mass index BMI, marital status, educational level and employee status), clinical data ［Osserman type, myasthenia gravis composite (MGC), other immunopathies, disease duration, frequency of outpatient visits per month, ratio of disease cost to income each month and frequency of symptoms during the past month］ and the MGQOL-15 Chinese version from 168 myasthenia gravis patients in one tertiary hospital of Sichuan Province. Results: The mean score of MGQOL-15 was 17.67±12.78. The score of the item “My occupational skills and job status have been negatively affected.” was the highest, followed by “I have trouble using my eyes.” and “I am frustrated by my MG.” Single factor analysis showed that MG patients’ QOL were different with different disease severity MGC (F=19.353，P＜0.001), ratio of disease cost to income each month (F=5.831，P＜0.001) and the frequency of symptoms during the past month (F=9.128，P＜0.001). Multiple regression analysis showed that disease severity MGC (β=0.743，P＜0.001), ration of disease cost to income each month (β=3.347，P＜0.001) and the frequency of symptoms during the past month (β=2.216，P＜0.003) were the main predictors of HRQOL in the MG patients. Conclusions: Our study showed that the MGQOL-15 is helpful for clinicians to evaluate MG patients’ QOL regularly, investigate the influencing factors and implement corresponding interventions the so as to improve the patients’ quality of life. Disease severity MGC, ratio of disease cost to income each month and the frequency of symptoms during the past month were the main predictors of MG patients’ QOL. Clinicians should pay more attention to MG patients’ disease severity MGC and the frequency of symptoms during the past month.

Objective： To investigate the regulation mechanism of RhoA signaling pathway during the enamel formation by using the EGFP-RhoA Dominant Negative （EGFP-RhoADN）transgenic mice model, from the aspect of adherens junctions, and to provide a theory basis for mechanism of enamel development defects. Methods: The enamel thickness of mandibular first molars of EGFP-RhoADN transgenic mice and wild type (WT) mice were observed by scanning electronic microscopy at 20 kV, and the enamel thickness of the distal face of the central cusp was measured at 10 locations via analysis by ImageJ (Rasband, 1997-2009). The enamel organs from mandibular first molars from postnatal-4-day (P4) EGFP-RhoADN mice and wild type mice were isolated, and the total RNA and protein were extracted from the epithelium of the enamel organs. The expression level of the adherens junctions components in ameloblasts layer of the postnatal-4-day EGFP-RhoADN transgenic mice and wild type mice mandibular first molars were detected by real-time PCR and Western blot assay. Results: The EGFPRhoADN transgenic mice had decreased enamel thickness in their bilateral mandibular first molars versus those of control group (n=20), and enamel thickness was (84.60±0.20) μm vs. (106.24±0.24) μm, P＜0.05 .The protein expressions of E-cadherin, α-E-catenin and pan-cadherin in ameloblasts layer of postnatal-4-day EGFP-RhoADN transgenic mice molars were down-regulated, and the protein level of β-catenin in ameloblasts layer of P4 EGFPRhoADN transgenic mice molars was up-regulated. The mRNA level of E-cadherin in ameloblasts layer of P4 EGFP-RhoADN transgenic mice molars was down-regulated versus that of WT mice, and the gene expression of E-cadherin was 0.93±0.01 vs. 1.00±0.02, P＜0.05. The mRNA level of β-catenin in ameloblasts layer of P4 EGFP-RhoADN transgenic mice molars was up-regulated versus that of WT mice, and the gene expression of β-catenin was 1.23±0.03 vs. 1.00±0.05, P＜0.05. Conclusion: In the mandibular first molars of EGFP-RhoADN transgenic mice, the enamel formation was disrupted and the adherens junctions of EGFP-RhoADN transgenic mice ameloblasts were implicated during amelogenesis. RhoA signaling pathway may play a critical role in enamel development by altering the adherens junctions in ameloblasts.

Objective： To investigate the correlation between matrix metalloproteinase (MMP)-2/MMP-9 levels and childhood caries, and the saliva levels of MMP-2/MMP-9 among healthy children and those with different degrees of dental caries, both before and after treatment. Methods: In the study, 368 children aged 3 to 5 years were separated into three groups: severe caries group (112 children), mild caries group (98 children) and caries free group (158 children). The children with severe caries were included in treatment group (83 children) after accepting a comprehensive treatment of caries. MMP-2 and MMP-9 levels were determined by enzyme-linked immunosorbent assay (ELISA) and the data were analyzed by the Statistics Package for Social Science (SPSS 13.0). The differences among severe caries group, mild caries group and caries free group were analyzed by SNK-q (Student Newman Keuls). The severe caries group and treatment group were compared by paired t test. The differences between each group were statistically analyzed. Results: There was no significant difference of the age and gender composition among severe caries group, mild caries group, caries free group and treatment group. The MMP-2 level of severe caries group ［(141.3±32.5) μg/L］ was higher than those of mild caries group ［(107.5±21.3) μg/L］ and caries free group ［(102.8±18.5) μg/L］ (P<0.05). There was no significant difference between mild caries and caries free group (P>0.05). After analysis of 83 children in the treatment group, the level of MMP2 ［(120.1±24.8) μg/L］ was lower than before ［(144.6±30.3) μg/L］ (P<0.05), but was higher than that of caries free group (P<0.05). The MMP-9 levels of severe caries group ［(445.8±68.1) μg/L］ and mild caries group ［(428.6±59.2) μg/L］ were higher than that of caries free group ［(385.4±60.6) μg/L］ (P<0.05), but the difference between severe caries group and mild caries group was not significant (P>0.05). After analysis of 83 children in the treatment group, the alteration of MMP-9 ［(432.2±64.7) μg/L］ was not significant either (P>0.05). Conclusion: The saliva levels of MMP-2 and MMP-9 in children with severe caries were higher than those in caries free children, even if the treatment was implemented, which suggests that the MMP-2 and MMP-9 in saliva might be related to the caries in children.

Objective： To investigate the clinical effect of eruption guidance appliance in the treatment of anterior cross bite in mixed-dentition children. Methods: In the study,10 mixed-dentition children with anterior cross bite，totally 12 incisors, were selected. Alginate was used to take upper and lower dentition impression and make a hard plaster model，which served as the eruption guidance appliance for treatment. The pre- and post-operative dental casts were digitized with SmartOptics Activity 880 scanner，and the three-dimensional overlapping models were obtained by reverse engineering software，Geomagic Studio 2012，then the threedimensional movements of the upper and lower incisors were analyzed using Imageware 13.2 software. The overbite and overjet were analyzed using the same methods. Measurement with copper wire was used to analyze the upper and lower arch length. Space analysis was the result by the sum of crown width minus the arch length. The crown width of unerupted permanent teeth was accor-ding to X-ray method to predict. The SPSS 17.0 software was used to analyze the pre-and post-operative measurements of the same child. The normality test of the measured data showed that it conformed to the normal distribution. Therefore，the t test and double side test were used，and the significance level was 0.05. Results: The course of treatment was (5.6±2.7) months. During orthodontic treatment, the upper incisors moved mainly labially（P<0.001）in three-dimensional displacement，and the lower incisors moved mainly the same direction（P=0.025）. During the treatment of eruption guidance appliance，the average overbite decreased (1.01±0.9) mm（t=-3.531，P=0.006），and the difference was statistically significant. There  was no statistically significant difference between the pre- and post-operative average overjet（t=0.771，P=0.460）. The severity of crowding in upper arch decreased (1.9±0.99) mm （t=-6.042，P<0.001），and that in lower arch decreased (1.9±0.74) mm （t=-8.143,P<0.001）， both of the differences were statistically significant. Conclusion: The anterior cross bite in mixed dentition could be corrected by eruption guidance appliance，and at the same time，the normal overjet and overbite were established，and the teeth were aligned.

Objective： Cytokines produced by various cells are strong local mediators of inflammation. Interleukin-1beta (IL-1β) and C-reactive protein (CRP) play essential roles in the development and progression of diabetes mellitus (DM). Thus periodontal diseases could be related to DM via the same mediators of inflammation. To evaluate plasma and gingival crevicular fluid (GCF) levels of IL-1β and CRP in adolescents with DM to further investigate whether DM has an impact on the levels of inflammation factors at an early stage, and to analyze the risk of developing periodontal diseases in adolescents with DM. Methods: A total of 121 adolescents aged from ten to sixteen years were enrolled, 41 adolescents diagnosed with diabetes mellitus were collected in the DM group, and 80 nondiabetic adolescents as the control group. The periodontal indices of each individual were recorded, including plaque index (PLI), modified bleeding index (mBI), probing depth (PD) and attachment loss (AL). GCF and intravenous blood samples were collected, and CRP and IL-1β levels were detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) PLI of DM group and control group were 1.23±0.05 and 0.95±0.04 separately, with significant difference (P=0.001). DM group and control group had mBI of 0.80±0.08 and 0.51±0.06 separately, with significant difference (P=0.003). Attachment loss was found in none of the subjects. PDs of DM group and control group were (2.37±0.51) mm and (2.31±0.05) mm separately, and there was no significant difference. (2) CRP in GCF was only detectable in partial of the individuals, with a detectable rate of 22.9% (11/48) in total. The detectable rate of CRP in GCF was significantly higher in DM group (38.5%) than that in control group (4.5%, P=0.006). The plasma level of CRP in DM group ［0.23 (0.15, 1.89) mg/L］ was higher than that in control group ［0.19 (0.12, 4.18) mg/L］, but without significance (P=0.776). (3) The plasma levels of IL-1β in DM group and control group were (14.11±0.57) ng/L and (14.71±0.50) ng/L separately, but there was no significance (P=0.456). GCF levels of IL-1β in DM group and control group were (12.91±1.95) μg/L and (17.68±3.07) μg/L, without significant difference (P=0.185). Conclusion: Periodontitis was not observed in adolescents with DM at an early stage. However, the rising levels of periodontal indices and CRP in GCF, might indicate that adolescents with DM have a higher risk of developing periodontal diseases in the future.

Objective： To investigate which shade guide, Vitapan Classical or Vita Bleachedguide 3D-Master, is better matched with the color of teeth in judging whitening effect, by comparing the color difference between shade tabs and corresponding teeth underwent cold light tooth whitening. Methods: A total of 60 patients underwent Beyond cold light tooth whitening from May 2014 to April 2016. The patients were divided into two experimental groups according to the shade guide used. Vitapan Classical shade guide was used to judge whitening effect in one group, and Vita Bleachedguide 3D-Master shade guide was used in another. Shade matching was carried out before and after whitening in both the two groups, and the results were recorded by digital photographs. Shade matching procedures were carried out by two doctors independently. If they chose the same tab, it would be seen as the shade matching result; While if they chose different tabs, another doctor would be invited to make a decision. Photographs were taken in preset conditions: intraoral photos of the full dentition in the front, and the proportion of shooting was 1 ∶3; aperture was F22; shutter speed was 1/200; intensity of flash was M/8; ISO value was 200. The photographs were analyzed by Photoshop software. Chromatic values were measured, and color diffe-rence values were calculated. Measuring of chromatic values was carried out by three doctors indepen-dently, and all the photos were measured twice by each doctor. Six measure results of each photo were recorded, and the maximum and the minimum were excluded, then the mean was seen as the final result. The color difference values were compared by independent-sample t test. Besides, changes of shade tabs after whitening in the two groups were recorded. Results: Color difference value was 5.06±1.71 in Vitapan Classical group, and 3.39±1.36 in Vita Bleachedguide 3D-Master group. There was statistically significant difference between the two groups (t=4.68，P<0.001). Change of shade tabs was 3.63±1.75 in Vitapan Classical group, and 2.23±1.01 in Vita Bleachedguide 3D-Master group. Conclusion: Vita Bleachedguide 3D-Master is better matched with the color of teeth, so it is preferred in judging the effect of cold light tooth whitening.

Objective： To evaluate the accuracy of optical coherence tomography (OCT) in detecting root cracks after root canal instrumentation using histological gold standard. Methods： Twenty complete extracted human mandibular incisors that were free of caries, calculus, and root treatment were chosen and accessed coronally with a diamond bur, then mounted in resin blocks with alginate impression material using simulated periodontal ligaments, and the apex was exposed 3 mm. The teeth were stored in water at room temperature. Then the teeth were then instrumented to the major apical foramen (AF) at #30/0.09 using ProTaper Universal rotary nickel titanium system(Dentsply Maillefer, Ballaigues, Switzerland), irrigation with 1% sodium hypochlorite (NaOCl) by using a 26gauge needle followed after each instrument. The apical root was scanned with 360° of rotation by Swept-Source Optical Coherence Tomography （SS-OCT） (wavelength: 1 310 nm, scan rate: 20 kHz, axial resolution: 16 μm) with driving device（stepper motor and lifting platform）. The reconstruction images of axial planes 1, 2 and 3 mm from the apex were examined and the root cracks were blindly diagnosed by two observers. The horizontal section was performed at 1, 2 and 3 mm from the apex using low speed disc saw (Leica SP1600, Wetzlar, Germany). The presence of cracks was noted under an optical stereomicroscope (ZOOM-630E) with a cold light source using as gold standard to evaluate the accuracy of OCT in detecting root cracks after root canal instrumentation. Results： After canals instrumentation with ProTaper Universal rotary nickel titanium system to #30/0.09, root cracks were detected in 9 of 20 teeth by histological examination. Crack lines were observed on 13 of 60 horizontal sections and cracks on 12 of the 13 sections were detected by OCT. No cracks were observed in the other 47 of the 60 horizontal sections，none of which was misdiagnosed by OCT. The overall accuracy rate for detection of root cracks with OCT was 0.983, the sensitivity was 0.923, the specificity was 1.000, the positive predictive value (PPV) was 1.000 and the negative predictive value (NPV) was 0.979. Conclusion： OCT may be a promising nondestructive imaging method for diagnosing root canal cracks after canal instrumentation.

Objective： To evaluate the effect of the vacuum-formed retainer on preventing the proximal contact loss between the implant supported crown and its adjacent natural teeth. Methods: Fortysix posterior implant crowns in the mandible including 92 interproximal contacts in 46 patients (19 men, 27 women) aged from 25 to 66 years were included. The participants in experimental group (22 cases) were vacuum-formed retainers at night, while participants in control group (24 cases) only received routine examination. The two groups were not different in age, gender, the time interval of the tooth loss and tooth position at baseline. Mesial and distal proximal contact tightness was measured using the orthodontic dynamometer and metallic articulating film immediately after crown delivery, and 1-month, 3-month, 6-month, and 1-year follow-up respectively. The articulating film was inserted interdentally from the occlusal direction, and then it was slowly removed in the buccal-lingual direction by the dynamometer. Increasing the number of films (N) piece by piece until the frictional force (F) was great than 0, and the number of films (N) was recorded. At each follow-up, proximal contact between implant crown and its adjacent teeth was considered to be loss if the number of films (N) used at immediate crown delivery passed without frictional force (F=0). Besides, the periodontal conditions ［scored according to the probing depth (PD), bleeding index (BI), mobility (M)］ and complaint of food impaction were recorded. The mesial and distal proximal contact loss rates were compared between the two groups at different times. Chi-square test or Fisher’s exact test was used for statistical analysis. Results: The proximal contact loss rate on the mesial surface of the implant supported crown continuously increased over the follow-up pe-riods. At the end of the 1-, 3-, and 6-month follow ups, 18.2%, 22.7% and 27.3% were identified for the contact loss rates on the mesial surface of the implant supported crown in the experimental group, respectively. Meanwhile in control group, the rates were 20.8%, 37.5% and 45.8%. No significant differences were observed at the end of the 1-, 3-, and 6-month follow ups（1-month：χ2=0.000，P =1.000； 3-month： χ2=1.183， P=0.277； 6-month： χ2=1.697， P=0.193）. The proximal contact loss rate on the mesial surface in control group (62.5%) was significantly higher than that in the experimental group (31.8%, χ2=4.330, P=0.037) at the end of the 1-year follow-up. However, no statistical difference was found on the distal surfaces between the two groups during the whole follow-up periods. The first open contact was noted 1 month after crown insertion. Conclusion: By wearing vacuum-formed retainer for one year, the incidence of open contacts between the posterior implant prostheses and mesial adjacent teeth in the mandible has been reduced.

Objective： To investigate the effect of smear layer on apical sealing ability in teeth obturated with mineral trioxide aggregate (MTA) Plus as retrofilling materials. Methods: Fifty freshly extracted maxillary anterior teeth or premolars with single root canal were used in this study. All teeth were instrumented to master apical point 60# by using the step-back technique, obturated with lateral condensation technique, and then apical resected. A root-end cavity was then instrumented with an ultrasonic diamondcoated tip. Then the selected teeth were randomly and equally divided into two groups (n=25). In the experimental group (smear-), the teeth were irrigated with 0.17 g/L ethylenediaminetetraacetic acid (EDTA) to remove smear layer on the root-end cavity wall; in the control group (smear+), the teeth were irrigated with physiological saline. Five teeth were extracted to evaluate the cleanliness of root end cavity walls under a videomicroscope, respectively. The scanning electron microscope (SEM) evaluation was also performed for the presence of smear layer and open tubule. For the additional 40 teeth, the root-end cavities were filled with MTA Plus. The quantitative apical leakage of each teeth was evaluated by measuring the concentration of leaked sucrose in apical reservoir on 1, 7, 14, 21, 28, 35, 42, 49 and 56 days, respectively. The samples were stored at 37 ℃ and 100% humidity for 56 days. Statistical analysis was done with ANOVA for repeated measurement design data. Results: Removal of the smear layer did not cause significantly less apical leaked sucrose than that when the smear layer was left intact for 56 days (P>0.05). There were statistically significant differences at the concentration of leaked sucrose among different observation time points (P<0.05) . Conclusion: It may be concluded that removing the smear layer may not be necessary in rootend cavities filled with MTA Plus.

Objective： To analyze and characterize the separation effectiveness of self-constructed asymmetrical flow field-flow fractionation system on proteins and lipoproteins, to achieve the optimization of the experimental conditions when separating lipoproteins by orthogonal design test and to investigate the carrier viscosity’s influence on separation effectiveness. Methods: The evaluation of asymmetrical flow field-flow fractionation separation capacity was conducted by using two standard proteins (carbonic anhydrase and thyroglobulin). Under the optimized separation conditions of carbonic anhydrase and thyroglo-bulin, the channel actual thickness (after assembling, the actual thickness of separation channel was less than initial thickness) was calculated by the analytes’ elution time based on the hydrokinetic theory. With orthogonal design test the optimized experimental conditions were studied and statistical analysis was carried on to find out the factors with statistical significance which needed further exploration. Results: According to the hydrodynamics principle and Stoke’s function, the channel actual thickness was mea-sured to be 164 μm by separating the two standard proteins, carbonic anhydrase and thyroglobulin, under proper experimental conditions. By the optimization based on orthogonal design test, base-line separation (the resolution had to be higher than 1.50) was achieved. The resolutions of the two experiments were 1.61 and 1.58.According to previous study/ pre-study and supporting theory, in the orthogonal design test, the total 5 factors were integrated for comprehensive investigation: the total flow rate (3.00, 3.50, 4.00, 4.50 mL/min), focus time (3.00, 3.50, 4.00, 4.50 min), transition time (0.5, 1.0, 1.5, 2.0 min), pH of the carrier fluid(6.8, 7.00, 7.20, 7.40) and viscosity of the carrier fluid hydroxypropylmethylcellulose concentration: 0.00%, 0.03%, 0.06%, 1.00%). Among the 5 factors, viscosity was found to have the statistical significance on separation effectiveness which was further investigated. The resolution of high density lipoprotein and low density lipoprotein was increased by the increasing viscosity which also caused more obvious negative spikes. Conclusion: The separating capacities of self-constructed asymmetrical flow field-flow fractionation system on lipoproteins were verified to be effective and an optimized experimental condition was found to achieve the base-line separation of high density li-poprotein and low density lipoprotein. Viscosity of the carrier fluid was proved to have the statistical significance on lipoprotein separation.

Pigmented extramammary Paget’s disease (PEMPD) is an uncommon intraepithelial adenocarcinoma and a rare variant of Paget’s disease, characterized as a superficial pigmented scaly macule clinically and an increased number of melanocytes scattered between the Paget’s cells histologically. So it may be confused clinically and histologically with melanocytic tumors, dermatitis and other dermatoses. Different therapeutic attitudes are required in this case of adenocarcinoma in situ as opposed to melanoma and dermatitis. Condyloma acuminatum (CA) is a common sexually transmitted disease caused by human papilloma virus infection, which is also called as genital warts. In this article, we first reported a case of a 65-year-old Chinese man who had pigmented extramammary Paget’s disease complicated with CA. This patient presented with verrucous papules on the scrotum for 3.5 years, infiltrative erythema with itch on the mons pubis for 3 years, and scrotum and penis involved gradually for 4 months. Physical examination showed a 8 cm×10 cm dark red patch on the upper part of the scrotum, penis and mons pubis, as well as few maculopapules and nodules. Histopathologic examination of the lesion on the scrotum revealed a focus of Paget’s disease, characterized by the presence of large round cells with abundant pale or granular/dusty cytoplasm, pleomorphic vesicular nuclei and prominent nucleoli (Paget’s cells), while the histology of the verrucous lesion was consistent with CA. Immunohistochemistry was performed, which showed diffuse positive staining with CK, CEA, PAS, CK20, EMA, CK7, and Ki-67 (40%), HER2 in Paget’s cells and negative with P53, P16, CK5/6, S100, MelanA, HMB45, estrogen receptor, progesterone receptor, and gross cystic disease flid protein 15 (GCDFP-15). Human papillomavirus-11 (HPV-11) was positive by genotyping using gene amplification in the lesion of scrotum. According to clinical features and laboratory findings, a diagnosis of PEMPD complicated with CA was made. Local excision of the lesion was performed and sent for histological examination, with all margins clear of tumor. Both aforementioned diseases often occur in the vulva. Even so, it has been rarely reported coexisting of the above two diseases, of which the clinical significance and association are also unclear. In this article, we also reviewed the literature relating to PEMPD, and on this basis, the profile of this disease is discussed including its pathogenesis, clinical manifestation, diagnosis, treatment and advances. Due to PEMPD occasionally accompanied with an underlying carcinoma, it’s essential to make an accurate diagnosis. Besides, review of the literature reveals that pigmented variant of Paget’s disease could be initially misdiagnosed as melanocytic tumors and other dermatoses unless the entity is considered in the differential diagnosis and additional confirmatory studies are performed.

Cornual pregnancy is one of the diseases caused by embryo embedment at abnormal site. Since few women with cornual pregnancy continue to a middle or late gestation are at a relatively increased risk of uterus rupture，placenta accrete，postpartum hemorrhage and some other severe obstetric complications. We reported two cases of cornual pregnancy at the third trimester, including their clinical symptoms, diagnoses, treatments and obstetric outcomes. Patient 1 had regular prenatal examination. The ultrasound scan at the second trimester showed that the placenta was located at the right fundus of uterus and the myometrium was thin. She had sudden-onset abdominal pain and hypovolemic shock at the end of 33 weeks of gestation. Emergency laparotomy revealed right cornual pregnancy rupture and delivered a dead fetus. After removing the residual gestational tissue and repairing the uterine defect, a live infant was born by cesarean section three years later. Patient 2 was found an unusually located placenta accreta at the right cornu when cesarean section was performed for twin pregnancy and pre-eclampsia. Conservative treatments were tried to reduce bleeding, such as strong contractive drugs，B-Lynch suture，bilateral ascending branch of uterine artery ligation, but they all failed. The patient developed to disseminated intravascular coagulation and had to accept hysterectomy at last. Through analysis of the above two cases and review of related literature, we explored the diagnoses and management of the patients with cornual pregnancy at the late trimester. Ultrasonography is essential to diagnose cornual pregnancy, especially at the early stage, and the abnormal images need special attention during the whole term. Besides magnetic resonance imaging is an alternative method to evaluate the location and placenta accrete. Since cornual pregnancy is always accompanied with placenta accrete, which tends to result in uncontrollable postpartum hemorrhage and increase maternal mortality, cesarean section is suggested once diagnosed and individualized treatment strategy is made according to specific circumstances, including age, bearing requirement, severity of the disease, underlying disease and so on. Therefore, adequate preparation is very important and necessary before surgery. Drugs and conservative surgeries should be considered first when hemorrhage happens, however, hysterectomy is the last method to save patients’ lives when other treatment doesn’t work.