A prognostic model for assessment of outcome of root canal treatment in teeth with pulpitis or apical periodontitis / 北京大学学报(医学版)

OBJECTIVE@#To present a prognostic model for evaluating the outcome of root canal treatment in teeth with pulpitis or apical periodontitis 2 years after treatment.@*METHODS@#The implementation of this study was based on a retrospective study on the 2-year outcome of root canal treatment. A cohort of 360 teeth, which received treatment and review, were chosen to build up the total sample size. In the study, 143 teeth with vital pulp and 217 teeth with apical periodontitis were included. About 67% of the samples were selected randomly to derive a training date set for modeling, and the others were used as validating date set for testing. Logistic regression models were used to produce the prognostic models. The dependent variable was defined as absence of periapical lesion or reduction of periapical lesion. The predictability of the models was evaluated by the area under the receiver-operating characteristic (ROC) curve (AUC).@*RESULTS@#Four predictors were included in model one (absence of apical lesion): pre-operative periapical radiolucency, canal curvature, density and apical extent of root fillings. The AUC was 0.802 (95%CI: 0.744-0.859). And the AUC of the testing date was 0.688. Only the density and apical extent of root fillings were included to present model two (reduction of apical lesion). The AUC of training dates and testing dates were 0.734 (95%CI: 0.612-0.856) and 0.681, respectively. As predicted by model one, the probability of absence of periapical lesion 2 years after endodontic treatment was 90% in pulpitis teeth with sever root-canal curvature and adequate root canal fillings, but 51% in teeth with apical periodontitis. When using prognostic model two for prediction, in teeth with apical periodontitis, the probability of detecting lesion reduction with adequate or inadequate root fillings was 95% and 39% 2 years after treatment.@*CONCLUSION@#The pre-operative periapical status, canal curvature and quality of root canal treatment could be used to predict the 2-year outcome of root canal treatment.

Nutrient Intakes of Pregnant Women and their Associated Factors in Eight Cities of China: A Cross-sectional Study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>During the last 3 decades, China has dramatic changes of the dietary pattern among its citizens, particularly in urban cities. This study aimed to determine the nutrient intake status and factors associated with nutrient intakes of urban Chinese pregnant women now-a-day.</p><p><b>METHODS</b>The multistage stratified random sampling method was applied in the cross-sectional study. 479 women in three trimesters of pregnancy from eight cities of China were recruited. Nutrient intakes were evaluated with one 24 h dietary recall, and compared with the Chinese Dietary Reference Intakes (DRIs) 2013 for available nutrients.</p><p><b>RESULTS</b>Most pregnant women had imbalanced macronutrient distribution with excessive energy derived from fat. Intakes of Vitamin A, B 6, calcium, magnesium, and selenium were below Chinese Recommended Nutrient Intake (RNI) and Estimated Average Requirements (EARs) in all trimesters. Most pregnant women took more folic acid in the first trimester with a significant decrease in the second and third trimester (P < 0.05). Shortfall in iron intake was found in the third trimester whereas some women may be at the risk of excessive iron intake. Intakes of thiamin met RNI in the first trimester but were below EAR in all trimesters. Trimester phasing was positively associated with most nutrients (P < 0.05). Prepregnancy body mass index was inversely associated with energy, fat, Vitamin C, and calcium intake (P < 0.05). Educational level and household income were positively associated with folic acid intake (P < 0.05).</p><p><b>CONCLUSIONS</b>Current prenatal dietary choices of urban pregnant women in China are imbalanced in the nutrient intake when compared with national DRIs 2013, particularly in intakes of energy derived from fat and micronutrients. Appropriate dietary advice to pregnant women should promote a balanced diet with emphasis on avoidance of foods of high fat content and incorporation of foods that are good sources of the key micronutrients that are usually lacking in a regular pregnancy diet. Further research is needed to understand the eating habits and food patterns that contribute to this imbalanced diet in order to be able to effectively improve prenatal women's nutrient intake status.</p>

Analyses on the characteristics and the trends of pneumoconiosis notified between 1997 and 2009, in China / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To describe the incidence of pneumoconiosis reported in China from 1997 to 2009 and investigate the epidemiological trends and characteristics of pneumoconiosis, and to provide basic data for formulating the guidelines and policies for control of pneumoconiosis, research on pneumoconiosis, and establishing the time series model for monitoring and early warning of pneumoconiosis.</p><p><b>METHODS</b>The national database of new cases of pneumoconiosis reported from 1997 to 2009 was subjected to systematic arrangement, descriptive analysis, and trend test using SPSS 15.0. The statistical indices included number of new pneumoconiosis cases in each year, types of pneumoconiosis, regional and industrial distributions of pneumoconiosis cases, work types of pneumoconiosis cases, and the annual changes in mean length of service and mean age at the onset of pneumoconiosis.</p><p><b>RESULTS</b>From 1997 to 2009, a total of 122 333 new cases of pneumoconiosis were reported; the number of new cases increased since 1998, but fell to 7620 in 2003, and then it increased again to a maximum of 12 492 in 2009. Of all patients, 87.5% were cases of coal-workers' pneumoconiosis and silicosis; 54 068 (44.2%) were coal-workers' pneumoconiosis cases, and 52 930 (43.3%) were silicosis cases. The pneumoconiosis cases were distributed mainly in Hunan Province (12 995 cases, 10.6%), Shandong Province (8952 cases, 7.3%), and Sichuan Province (8417 cases, 6.9%). Most cases were distributed in coal industry (61270 cases, 50.1%), architectural, material industry (9754 cases, 8.0%), nonferrous metals industry (9380 cases, 7.7%), and metallurgical industry (8773 cases, 7.2%). The work types of these cases mainly included tunneling as the main work (15 659 cases, 12.8%), mining as the main work (15 009 cases, 12.3%), drilling (14 010 cases, 11.5%), tunneling (12 122 cases, 9.9%), and hybrid coalmine work (10 612 cases, 8.7%). The mean length of service at the onset of pneumoconiosis in new cases of pneumoconiosis was shortened from 1997 to 2009, with a median length of service of 20.00 years; the median lengths of service at the onsets of coal-workers' pneumoconiosis, silicosis, and asbestosis were 21.58, 17.00, and 20.00 years, respectively. The median age at the onset of pneumoconiosis was 51.00 years, and the mean age of onset in new cases of pneumoconiosis increased over the 13 years.</p><p><b>CONCLUSION</b>The incidence of pneumoconiosis is still high, with a marked concentrated trend in several industries, work types, and pneumoconiosis types, a marked rising trend in number of new cases, and a marked shortening trend in length of service at the onset of pneumoconiosis. The prevention and control of pneumoconiosis should be enhanced in key industries and for people engaging in key types of work according to the epidemiological characteristics of pneumoconiosis. In addition, the demonstration project of comprehensive prevention and control of occupational dust hazards should be carried out, and the monitoring and early warning system for pneumoconiosis should be established.</p>

Study of estimation method for incidence of new cases of coal workers' pneumoconiosis in China / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To estimate the coverage level of case reporting for coal workers' pneumoconiosis (CWP) and the incidence of CWP in China according to the data from CWP reporting database in China as well as the data on annual raw coal output, coal workers, etc. from relevant year books, and to provide scientific data for CWP control measures.</p><p><b>METHODS</b>The data on the numbers of coal workers and annual raw coal outputs of national top 100 enterprises in coal sector (Top 100 in coal sector) were acquired from China Coal Industry Yearbook; the annual per capita output of raw coal in each enterprise was calculated. The numbers of coal workers in the enterprises other than the Top 100 were estimated based on the annual per capita output of raw coal in the Top 100 and the annual raw coal outputs of the enterprises other than the Top 100. The numbers of coal workers in the enterprises that reported CWP cases were estimated based on the distribution of these enterprises in China, and the coverage rates of case reporting in the Top 100 and other enterprises were calculated accordingly. The total number of CWP cases and the number of CWP cases due to per million tons of raw coal output were estimated according to the coverage rates of case reporting and the total numbers of reported CWP cases in China.</p><p><b>RESULTS</b>The mean coverage rates of case reporting in the Top 100 and other enterprises were 55.34% and 5.18%, respectively. The estimated mean numbers of new CWP cases in the Top 100 and other enterprises were 3088 and 98205, respectively; the estimated total number of new CWP cases nationwide was 101293. The estimated mean numbers of new CWP cases due to per million tons of raw coal output were 2.05 in the Top 100 and 7341 in other enterprises. The number of reported CWP cases accounted for 6.7% of the estimated number of CWP cases (6796/101293).</p><p><b>CONCLUSION</b>It is urgent to enhance occupational disease control in coal sector, and the estimation results for CWP should be spread and applied. The system of occupational disease control should be further improved.</p>

Prevalence of self-reported allergy, food hypersensitivity and food intolerance and their influencing factors in 0-36 months old infants in 8 cities in China / 中华儿科杂志

<p><b>OBJECTIVE</b>To measure the prevalence, the possible causes and the influencing factors of allergy, food hypersensitivity and food intolerance in 0-36 month old infants in 8 cities in China.</p><p><b>METHOD</b>Totally 2632 infants from the outpatient departments of prevention and health care of two representative hospitals in 8 Chinese cities were randomly selected by applying multistage cluster sampling method from October 2011 to March 2012, and a one-on-one survey to infants' parents was conducted to investigate infants' sensitization status.</p><p><b>RESULT</b>Self-reported infant allergy rate was 17.97% (473/2632) ; self-reported food hypersensitivity and food intolerance rates were 6.53% (172/2632) and 4.26% (112/2632) , respectively. The proportion of self-reported food hypersensitivity of 0-12 months old infants was 4.47% (74/1656) and their top five allergens in a descending order were eggs (28.38%) , shrimp (25.68%) , fish (21.62%) , milk (18.92%) and wheat (4.05%) . The proportion of self-reported 13-36 months old infant's food hypersensitivity was 10.05% (98/976) . The top five allergens were shrimp (33.93%) , fish (26.79%) , eggs (23.21%) , milk (12.50%) and soy (3.57%) in 13-24 months group, while fish (38.24%) , shrimp (35.29%) , eggs (20.59%) , milk (20.59%) and peanuts (2.94%) in 25-36 months group. Both 7-12 and 13-24 month old were the highest incidence (both of them were 11.98%, 58/484) of age for developing food hypersensitivity and 7-12-month old was also the highest incidence (8.47%, 41/484) of age for food intolerance. The self-reported food intolerance rate was 3.68% (61/1656) and 5.23% (51/976) in the two age groups, respectively. Age, parental history of allergy and father's educational level (OR was 2.452, 1.482 and 2.598, respectively, P < 0.01) were the risk factors of food hypersensitivity; within two weeks of sickness (OR = 1.267, P < 0.05) was the risk factor of food intolerance.</p><p><b>CONCLUSION</b>Infancy was the most vulnerable period of life of getting allergy, therefore, it is necessary for all infants to prevent allergy through a variety of effective strategies.</p>

Silicosis in automobile foundry workers: a 29-year cohort study / 生物医学与环境科学（英文）

<p><b>OBJECTIVES</b>The purposes were to determine the relationship between silicosis among foundry workers and their cumulative exposure to silica dust, and to establish a regression model to predict the risk for developing silicosis by a given length of employment and air concentrations of silica at worksites.</p><p><b>METHODS</b>A 29-year cohort study was conducted, including all those employed for more than one year during January 1, 1980 to December 31, 1996 and all members of the cohort were followed-up to December 31, 2008. In total, 2009 workers of an automobile foundry in Shiyan, Hubei province were recruited in the study, 1300 at eight worksites including sand preparation, cast shakeout, and finishing, melting, moulding, core-making, overhead crane operation and pouring as exposed group, and the other 709 auxiliary workers at the same factory, such as electricians, inspectors, fitters, and so on, as control group. Person-years of observation were calculated by persons observed and years followed-up for each of them. Person-year incidence of silicosis and its relative risk (RR) or odds ratio (OR) and 95% confidence intervals (CI) among the workers were estimated, adjusted for relevant factors with logistic regression model using SPSS version 15.0 software.</p><p><b>RESULTS</b>Totally, 2009 workers were followed-up for 37 151 person-years and 48 cases of silicosis were found, with an overall incidence of 1.34 per thousand, 2.02 per thousand in exposed group, and 0.15 per thousand in control one. Risk of silicosis was significantly higher in the exposed group than that in the control one (RR = 13.13, 95% CI 3.18-54.13), higher in men than that in women (RR = 13.92, 95% CI 1.92-100.93). Risks of silicosis varied by job, highest in those exposed to cast shakeout and finishing (RR = 28.14, 95% CI 6.43-123.11), followed by those exposed to pouring (RR = 22.23, 95% CI 5.01-98.55) in the foundry. Average length of employment at onset of silicosis was 25.94 years, and silicosis incidence increased with length of employment. Average age at onset of silicosis was 47.83 years old. The risk of silicosis in workers with pulmonary tuberculosis was 2.57 folds as those without it (P < 0.01). Ten deaths were recorded in those with silicosis, with a case-fatality rate of 20.83 percent three of them died of lung cancer, three of liver cancer, two of ischemic heart disease, and two of other diseases as their immediate causes of death. Incidence of silicosis in foundry workers positively correlated with their cumulative silica exposure (OR = 3.00, 95% CI 2.34-3.83). Risks of silicosis increased by 4.38 folds with an increase of 1 mg/m3-year of cumulative silica exposure, and by 3.79 folds with smoking, respectively, adjusted for alcohol drinking and age. Based on a logistic regression model fitted, incidence of silicosis is expected to be 44.6 per thousand for those with daily exposure to silica of 4.18 mg/m3 in average for 30 years, and if incidence of silicosis is expected to be less than 1 per thousand, daily exposure to silica should be controlled below 0.2 mg/m3 for those with 20 years of employment, or below 0.1 mg/m3 for those with 30 or 40 years of silica exposure.</p><p><b>CONCLUSIONS</b>At present, foundry workers in China still face high risk of developing silicosis. For lowering occurrence of silicosis in exposed workers, it seems necessary that current occupational exposure limits for silica at worksites in China should be reexamined and silica dust control measures be strengthened.</p>