Objective To study the relationship between magnesium level in serum of patients with coronary heart disease and the extent of coronary artery stenosis. Methods Patients were selected from Guangzhou Coronary Artery Disease Cohort in 3 hospitals in Guangzhou from October 2008 to December 2011. Patients' characteristics of smoking, alcohol consumption, physical activity and admission condition were collected by cross-sectional method. Their fasting blood specimens in the second day morning after admission were taken for test of blood routine, serum magnesium, and C-active protein (CRP). Univariate and multivariate logistic regressions were used to analyze the data. Results There were 1 980 patients in the Guangzhou Coronary Artery Disease Cohort, and 979 subjects were included in the final analysis. The average age was (63.63±11.84) years for the total patient cohort and (62.62±11.03) for the subjects included (P<0.01), the average BMI was (23.88±3.33) for the cohort and (23.87±3.36) for the subjects (P>0.05), and proportion of the males was 65.60% for the cohort and 73.24% for the subjects (P<0.01). In the univariate logistic regression, the relationship between different serum magnesium level and coronary artery stenosis >75% had statistically significant in male, but not in female. After adjusted for age, BMI, systolic blood pressure, smoking, alcohol consumption, physical activity in the multivariate logistic regression, the serum magnesium levels at 0.39-0.84, 0.92-0.99 and >0.99 mmol/L had significant risk for coronary artery stenosis >75% compared with those at 0.85-0.91mmol/L in males (OR: 1.93, 1.77, 2.14, respectively). Conclusion Serum magnesium level and coronary artery stenosis in male patients were not a simple liner relationship. It might be conducive to the prevention of coronary heart disease to keep serum magnesium at moderate level.

Objective To develop a method for measurement of trimethylamine-N-oxide (TMAO)-microbiota-generated metabolite of choline in serum by stable isotope dilution high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) and to study its accuracy and stability. Methods Proteins in samples were precipitated with three volumes of 10 μmol/L internal standard d9-TMAO in acetonitrile and supernatants were analyzed after injection onto a SiO2 column (2.1 mm×100 mm, 5 μm.) and equilibrated with 30% solution A (10 mmol/L ammonium formate, pH = 3.0) and 70% solution B (acetonitrile). Results Lower limit of detection was 0.003 μmol/L and the lower limit of quantitation was 0.063 μmol/L at linear range of 0.16 - 20.00 mol/L (r2=0.999 9). The intra-batch and inter-batch coefficients of variance were 2.03% - 2.64% and 6.00% - 9.94%, and the recovery rates were 89.5% - 103.0%, respectively. Stability study revealed that the storage temperature and time could affect the concentration of TMAO. TMAO in serum was stable both during storage at -80 ℃ and throughout multiple freeze thaw cycles. Conclusion HPLC-MS/MS assay has characteristics of rapidness, accuracy, precision, and high-throughput nature and can meet the detection requirements for large quantity of blood samples.

Objective To investigate the status and associated factors of alcohol consumption among residents in Guangdong Province, and provide basic data for health risk assessment related to alcohol consumption. Methods During 2009 to 2012, using multi-stage stratified cluster sampling, three different stages including large cities, medium cities, and rural areas were classified for the survey. Nine districts/counties were selected across the province. Six resident/village committees were sampled in each county,75 households were sampled in each resident/village committee,and then,family members aged 5 and over were selected to participate in the survey.Survey contents included personal general situation, alcohol drinking in the past 12 months, types of alcoholic beverage, frequency, average consumption of every time, etc. Descriptive epidemiological analysis was carried out on the survey. PROC SURVEYMEANS and PROC SURVEYFREQ were used for calculating standardized average intake and rate, and the multiple logistic regression analysis was used for analyzing factors related to alcohol consumption. Results A total of 9 672 residents aged 15 and above were investigated, and valid number was 8 972 residents, and the questionnaire response rate was 92.8%. Among 8 972 respondents, 57.7% were female, 38.0% at medium-sized cities, 58.7% aged 30 to 59 years, 56.9% had middle school education, 44.2% had annual income of <10 000 Yuan, 83.6% married, and 17.9% smokers. A total of 2 758 residents had been drinking over the past 12 months, the crude drinking rate was 30.7%, and the standardized drinking rate was 33.3%; the average daily alcohol intake of 2 758 drinkers was (9.6 ± 2.1) g; the average daily alcohol intake of 312 excessive drinkers was (74.6 ± 11.5) g. The proportion of excessive alcohol drinking was 15.6% (279/1 787) for men and 3.4% (33/971) for women to all alcohol drinkers. In the multiple logistic regression model, the subjects aged 18-29 (OR=2.971), 30-44 (OR=3.857), and 45-59 (OR=3.147) age groups, the annual income level of 10 000 - 25 000 Yuan (OR=1.229) and > 25 000 Yuan (OR=1.206), and smokers (OR=2.321) were more likely to drink alcohol, while those of female (OR=0.347), middle school education (OR=0.767), and primary school education and below (OR=0.592) were less likely to drink alcohol. Conclusion Alcohol intake of excessive drinking was higher, and it is necessary to carry out risk assessments for hazardous substances related alcoholic beverage to control the risks associated with alcohol consumption.

Objective To investigate the food and water intake during the first 3 days postpartum and analyze risk factors for the delayed onset of lactation among women in Guangzhou. Methods Data were collected from September 2013 to May 2014 in Guangzhou Women and Children's Medical Center. Three 24-hour dietary recalls (1 to 3 days postpartum) and questionnaire survey were conducted to collect food intake, demographic characteristic, maternal reproductive history, gestational age, delivery mode, postpartum analgesia, birth weight, feeding behaviors and condition of newborns of the delivery women. Factors associated with the delayed onset of lactation were identified with univariate and multivariate logistic regressions. Results Of the 237 pairs of delivery women and newborns, 204 participated in the study. The mean age of delivery women was (28.31±3.32) years. Among the participants, 98.0% were the Han nationality, 81.9% had the educational level at college or above, 75.5% were on the job during the pregnancy, 86.3% were primiparas, and 69.6% had natrural delivery. After delivery, proportions of three major macronutrients of protein, carbohydrates, and fat mothers took were 16.68%, 55.96%, and 27.60%, respectively, consistent with the ratios of 13%-15%, 50%-65%, and 20%-30% recommended by DRIs. Except eggs (104.4%), intakes of other food and water were below the recommended intakes. The consumptions of dairy (6.7%), fruits (21.0%), vegetables (21.0%), and bean products (26.7%) were at the lowest level. In addition, the intakes of energy and nutrients were seriously insufficient except niacin. The intakes of dietary fiber, vitamin C, and calcium were as low as 17.2%, 27.3%, and 29.4% of RNI/AI, respectively. The delayed onset of lactation accounted for 28.4% (58/204) and non-delayed ones, 71.6% (146/204). Multivariate unconditional logistic regression showed that primiparity (ORAdjust=5.66) and cesarean delivery (ORAdjust=2.60) were risk factors for the delayed onset of lactation, whereas breastfeed >2 times in the first 24 h and second 24 h (both ORAdjust=0.49) were protective factors for delayed onset of lactation. Conclusion Postpartum women in Guangzhou are at high risk of inadequate intakes of all kinds of food, water, energy and nutrients, and thus should be provided with dietary guidelines during early postpartum period. Primiparas and cesarean are risk factors for delayed onset of lactation, while the early breastfeeding experience within 48 h postpartum is beneficial to reduce the incidence of delayed onset of lactation.

Objective To understand dietary nutrition status of women in early pregnancy so as to provide scientific evidence for a more reasonable dietary recommendation for them. Methods A consecutive 3-day 24-h dietary recall method was used to investigate the dietary intake of women in early pregnancy who were enrolled in a cohort of a hospital in Dongguan City from April to August,2013. Recommended Nutrient Intakes (RNIs) of Chinese Dietary Reference Intakes and Dietary guidelines for Chinese pregnant women, women during lactation and children aged 0 to 6 years were used to evaluate the nutritional status of pregnant women. Results A total of 245 women aged between 20 and 35 years in early pregnancy were included in this study. The average age was (26.40±3.13) years and the average body mass index (BMI), (19.87±2.61). The average daily intake of energy was 1 456.00 kcal (80.89% of RNI). Protein to energy ratio (12.32%) was lower than RNI, whereas the fat to energy ratio (32.73%) was higher than RNI. Only the amount of niacin intake met the RNI (103.33% of RNI), while the intake amount of dietary fiber, sodium, calcium and vitamin B1 were 31.52%, 34.38%, 36.90%, 39.17% of RNI, respectively. The average daily intakes of cereals (238.43 g) and livestock meat (44.18 g) met RNI, fruit (218.10 g) was slightly above RNI, whereas vegetables (144.79 g), poultry (13.55 g), fish (31.60 g), milk and milk products (95.60 g), eggs (24.83 g), and beans and nuts (8.29 g) did not reach RNI. Among the pregnant women, 48.16% had excessive fruit intake compared with RNI, only 6.53% and 3.67% meet the RNI for vegetables and milk, respectively. Conclusion Nutrients and amount of food taken by most women in early pregnancy did not meet RNIs and reasonable nutrition guidance should be given to them.

Objective To evaluate the association of pre-pregnancy body mass index (BMI) and adverse pregnancy outcomes. Methods Pregnant women were surveyed in Guangdong Provincial Maternity and Child Care Hospital from January 1, 2009 to January 1, 2012. The content of the survey included the pregnant age, gestational age, gravidity, birth history, past medical history, history of smoking and metabolic diseases (hypertension, diabetes), and family inheritance history. Their weight gains during gestation and pregnancy outcomes were carefully followed up. Results A total of 3 608 women were enrolled in this study. Their average age was（28.25±4.13）years, average pre-pregnancy BMI was（20.34±2.82）, and average growth of gestational weight was （15.21±4.35）kg. The BMI and body weight increased with the increase in gestational weeks (both P<0.01). Among all the women, 669 were underweight (BMI<18.5), 2 476 had normal weight (18.5≤BMI＜24.0), and 463 were overweight or obese (BMI≥24.0) before pregnancy. Incidence rates of adverse outcomes in different groups were 6.73%（45/669）, 33.12%（820/ 2 476）, and 46.87%（217/463）, （P＜0.01 between the three groups）. The proportion differences of outcomes of pregnancy, preeclampsia, GDM, preterm birth, fetal macrosomia, and full-term low birth weight infants were statistically significant (all P < 0.01) for the women with different pre-pregnant weights. Preeclampsia, GDM, premature delivery, and incidence of macrosomia were positively correlated with the pre-pregnancy weights (r=58.37, 85.33, 50.20, 23.62, all P < 0.01). The incidence of full-term low birth weight infants was negatively correlated with pre-pregnancy weights (r= -10.15, P < 0.05). Conclusion Abnormal pre-pregnancy BMI may be closely related to adverse pregnancy outcomes. The pregnancy weight gain should be based on pre-pregnancy BMI with different patterns.

Objective To analyze epidemic characteristics of reported other infectious diarrhea (other than cholera，dysentery, typhoid and paratyphoid) in Guangdong Province in 2013 so as to provide evidence for preventing and controlling the disease. Methods Epidemiological and pathogenic data of reported cases of other infectious diarrhea were collected from the Infectious Disease Report Information System in China Information System for Disease Prevention and Control from January 1 to December 31,2013. Outbreak data were collected from the Public Health Emergency Management of Information System. Descriptive statistical analysis was performed. Results A total of 166 274 other infectious diarrhea cases were reported in Guangdong Province in 2013 with an annual incidence rate of 156.95/100 000. The cases were distributed across the twenty-one cities in Guangdong. The top five cities by cases were Shenzhen (41 111 cases), Guangzhou (18 900), Meizhou (11 386), Jiangmen (10 704), and Dongguan (10 691), whose cases accounted for 55.81% of the total cases of the province. The cases peaked in January, October, November, and December, accounting for 59.83% of the reported cases（99 485/166 274）. There were 98 356 males and 67 918 females and the male to female sex ratio was 1.45∶1. The children in the age group between 0 and 4 year-old were the main population with infectious diarrhea (130 424 cases, 78.44% of the total cases). The cases were mainly scattered children (130 274 cases, 78.35%). Nineteen outbreaks were reported and all caused by norovirus. There were 76 264 laboratory-confirmed cases accounted for 45.86% of the cases reported and 59 844 confirmed cases have reported the test results, including 58 241 viral cases (97.32% of the total cases) and 1 525 bacterial cases (2.55%)．The main pathogen of viral diarrhea was rotavirus (95.73%，55 756/58 241). The main pathogen of bacterial diarrhea was Salmonella accounting for 81.11% of the bacterial cases（1 237/1 525）. Conclusion The incidence peak of other infectious diarrhea appeared in autumn and winter in Guangdong Province in 2013. The scattered children under 5 years were the high risk group of the infectious diarrhea. All the outbreaks were caused by norovirus. Rotavirus was the main pathogen of the viral diarrhea and Salmonella, the main one of the bacterial diarrhea.

Objective To understand the performance of automatic early warning information system (AEWIS), evaluate its operating results, and to provide scientific basis for further improvement of communicable disease early warning patterns. Methods Descriptive analysis method was used to describe the characteristics of warning information sent out by AEWIS from 2008 to 2013. Sensitivity, positive predictive value and lead time were taken as the main evaluation indicators for analyzing operating results of AEWIS. Results AEWIS issued 13 021 warning signals from 2008 to 2013 and 12 of the signals were confirmed to be outbreaks or epidemics through field investigations. Twenty-four kinds of infectious diseases were identified from the all early warning information issued. A total of 11 888(91.30%) diseases were hand, foot, and mouth disease, other infectious diarrhea, mumps, dysentery, hepatitis C, and measles. The peak number of early warning signals were 4 880 from May to July, accounting for 37.48% of the total signals. The median response time from early warning signal to submitting abnormal information card was 0.40 hour. The sensitivity of AEWIS was 85.71% and the positive predictive value was 0.09%. The lead time of the 8 of 12 outbreaks of infectious diseases detected by AEWIS was negative. Conclusion The sensitivity of the warning system is high, but the positive predictive value is low. It is recommended to adjust the threshold timely and reasonable, so that the early warning system can play a role in early warning outbreaks of infectious diseases at the grassroots level.

Objective To explore current situation and relevant influencing factors of low motor constitution among primary and secondary school students in Guangzhou City, so as to provide scientific evidence for making effective interventions. Methods Students between the fourth-grade in primary school and the third-grade in senior high school, who have participated in the National Physical Health Survey of Students in Guangzhou City, were selected from 12 monitoring schools (3 middle schools and 3 primary schools, each from both urban and rural area) to conduct tests of height, weight, and motor constitution. "Questionnaire for National Physical Health Survey of Students in 2010" was adopted for this survey. Students whose velocity, explosive force, muscular endurance, endurance running, and body flexibility were lower than the average value of those at the same gender and age were determined as the low motor constitution group. Unconditioned logistic regression was used to analyze the factors influencing the motor constitution of the students. Results A total of 3 846 students aged 9-18 years were surveyed. Of them, 969 boys and 947 girls were from the city, and 954 boys and 976 girls were from the rural area. The ratio of low motor constitution was 9.88% (380/3 846) for the students in Guangdong City, of which, 11.65% (224/1 923) was for male students and 8.11% (156/1 923) for female ones; 11.85% (227/1 916) for urban students and 7.93% (153/1 930) for rural ones (both P<0.01). The analysis of unconditioned logistic regression indicated that the protective factors for low motor constitution were female, rural area, and seriously doing exercise between classes (OR: 0.63,0.65, 0.80); the risk factors were overweight, a weekly physical classes ≥ 3, unwillingness to take physical education classes, and reluctance in long-distance running (OR: 2.80, 1.31, 1.67, 1.40). Conclusion To improve the active willingness to do physical exercise, ensure appropriate amount of exercise load, and weight control is an effective way for students to improve their motor constitution and strengthen their physical physique.

Objective To establish a comprehensive evaluation index system on methadone maintenance treatment (MMT) service in China and determine the weight coefficients of the indexes at all levels. Methods Delphi method was used to screen the indexes, and Fuzzy comprehensive evaluation method, to calculate the weight coefficients. Results Eighteen experts with three years and above relevant experience on MMT were selected for counseling. Their average age was 37.78 years, and on average, had 5.28 years of working experience in MMT-related field. The motivation coefficients of experts in two rounds of counseling were 94.7% and 100.0%, respectively. Both of the authorization coefficients are 0.80. The coordination coefficients of experts for the four-level indexes are 0.41, 0.36, 0.30, and 0.32 in the first round, and are 0.71, 0.58, 0.51, and 0.47 in the second round, respectively. Through two rounds of counseling, 7 indexes at the first level, 23 at the second level, 63 at the third level, and 41 in the fourth level were finally established. Of the first-level indexes, medical service provision had the greatest weight (0.160 4), followed by the medical record management (0.154 9). Of the second-level indexes, establishing a coordinating mechanism between MMT clinics and drug control agencies weighted the greatest (0.071 0). Conclusion The evaluation index system on MMT service established in the study is comprehensive and reliable, and can provide a reference for construction and assessment of comprehensive evaluation index system on MMT service in China.

Objective To explore the application of ARIMA model in the prediction of the incidence of mumps and verify the feasibility and applicability of the model.Methods Incidence data of mumps in Nanjing from January 2004 to December 2012 were fitted with ARIMA model using SPSS 18.0 statistical software. The incidence rate from January to December 2013 was verified by the established model, and then, monthly incidence rates in 2014 were predicted and evaluated. Results A total of 14 871 mump cases were reported from 2004 to 2013, with average annual incidence rate of 21.78 /100 000. Each year the monthly incidence rates were fluctuated around 1.85/100 000. ARIMA (1，0，0) (2，1，0)12 model was set up as the optimal one. The model residual sequence was white noise. The parameters of the model were statistically significant except the constant term. MAPE was 29.63% and R2, 0.76. Monthly incidence rates from January to December 2013 fitting with the model were all within the 95% confidence interval, consistent with the change trend of the actual incidence, which verified the availability of the model. Predicted by the model, the annual incidence rate of mumps in 2014 was 1.48/100 000 and the peak months of incidence were April (incidence rate: 2.33/100 000), May (2.72/100 000), and June (2.52/100 000). Conclusion ARIMA model can be used to fit mumps incidence trends in time series, and for dynamic analysis and short term prediction of the incidence of mumps.