A Case-control Study of Environmental Risk Factors for Nonsyndromic Cleft of the Lip and/or Palate in Xuzhou,China

In this study, we sought to determine the association between environmental factors and nonsyndromic cleft of the lip and/or palate （NSCLP） to understand the etiology of the disease. A total of 200 NSCLP cases and 327 controls were recruited at the Maternal and Child Health Hospital of Xuzhou City. We conducted face-to-face interviews with the mothers of both cases and controls. The factors increasing the risk of NSCLP were a positive family history [odds ratio （OR）=56.74], pesticide exposure （OR=8.90）, and indoor decoration pollution （OR= 4.32）. On the other hand, the factors decreasing the risk of NSCLP were a high education level （OR=0.22） and supplementation of folic acid （OR=0.23） and multivitamins （OR=0.16）. Positive family history, pesticide exposure, and indoor decoration pollution are associated with the risk of NSCLP. In contrast, high education level and folic acid and multivitamin supplementation are protective factors against NSCLP.

THE STUDY ON RISK FACTORS ASSOCIATED WITH BREAST CANCER AMONG WOMEN IN TIANJIN, CHINA AND ADELAIDE, AUSTRALIA

To explore the possible explanation of the marked difference in the incidence of breast cancer between Chinese and Australian women, the authors have compared and analysed the results of two case-control studies completed recently in Tianjin, China and Adelaide, Australia. Of 10 known risk factors for breast cancer 9 were significantly higher in level in Adelaide women than in Tianjin women, i.e., women in Adelaide were much taller, heavier, more obese, earlier at menarche, later at first full-term pregnancy, more nulliparous, less parity, more in history of breast cancer in first degree relatives, more educated. From the 7 risk factors analysed by use of logistic regression model 5 factors, i.e., earlier age at menarche, later age at first full-term pregnancy, less parity, history of benign disease, and history of breast cancer in first degree relatives, were associated significantly with the increased risk for breast cancer in the Tianjin study, but not in Adelaide study. These factors being not associated with breast cancer in Adelaide women were unexpected. The explanation of the indefinite findings in Adelaide study was due to the fact that the level of the risk factor is universally high, relatively uniform and lack of categories. The difference in the risk factor distribution between cases and controle would not be seen in case-control studies, and significance of the risk factor therefore may not be found. According to data on diet survey in these two cities, the calories from fat was significantly higher in Adelaide women than in Tianjin women. The marked difference in incidence in women in the two cities resulted from the summing-up effect of a number of factors. The important role of fat intake in geographical incidence difference and in the development of breast cancer was also discussed.

A Genetic Susceptibility Study of Lung Cancer Risk Potentially Associated with Polycyclic Aromatic Hydrocarbon Inhalation Exposure

For lifetime non-smokers, lung cancer risk is mainly associated with inhalation exposure to air pollution. For the Chinese population, indoor air pollution due to solid fuel combustion has been the primary source of inhalation exposure for decades. Polycyclic aromatic hydrocarbons （PAHs） are the by-products of incomplete combustion.

A STUDY OF PRECANCEROUS GASTRIC LESIONS IN A HIGH RISK POPULATION

A study of precancerous gastric lesion was conducted in a randomly selected high risk population in Linqu, Shandong Province of China. 849 subjects aged from 30-64 were examined bioptically. There were 8 cases of gastric cancer, the prevalence rate was 0.9%. 169 subjects were diagnosed to be dysplasia, the prevalence rate of dysplasia was increased significantly with age. The regression equation was Y=0.47X-0.25. The prevalence of CAG was found in 36 per cent of the studied subjects and both dysplasia and CAG were more serious in the antrum than the. fundus. The results showed a natural history of precancerous gastric lesions in a high risk population in a high risk area.

How Work Organization Affects the Prevalence of WMSDs: A Case-control Study

Objective In this study, we aimed at exploring the association between work-related musculoskeletal disorders（WMSDs） and work organization based on a case-control study. Methods A total of 1938 workers who claimed to suffer from WMSDs were selected from Beijing, Henan, Hubei, and the Guangdong province. The control group consisted of 2009 workers employed in similar industries without severe disease or musculoskeletal discomforts. We used a modified version of the questionnaire developed by the NMQ and the DMQ to investigate individual and work-related factors. Results A total of 13 variables（P〈0.1） were selected by the chi-square test and finally, 7 variables entered into the equation, with 6 variables reaching statistical significance（P〈0.05）. The odds ratios（OR） of ＇work changing with season＇ and ＇sufficient rest time＇ did not reach 1（0.749 and 0.441, respectively）. In addition, ＇sufficient rest time＇ seemed to be the stronger protective factor according to its higher standardized coefficient. And ＇repetitive work every minute＇, ＇constantly repetitive work＇（every day）, ＇shortage of site personnel＇, and ＇often switching shifts with others＇ seemed to be the risk factors. Conclusion Work organization may have comprehensive effects on the occurrence of WMSDs. This pattern of associations suggests that further investigation into the mechanism of how work organization affects the prevalence of WMSDs is required.

The Beijing Desheng Diabetic Eye Study:rationale,design,methodology and baseline data

AIM： To present the rationale, design, methodology, and the baseline data of the Beijing Desheng Diabetic Eye Study（BDDES）, and to determine the prevalence of diabetic retinopathy（DR） and possible risk factors in patients with type 2 diabetes mellitus（T2DM） in an urban community of Beijing, China.METHODS： Community-based prospective cohort study of persons diagnosed with T2DM aged 30 y or older. The main variables of interest are the presence and progression of DR as determined by the standardized ETDRS grading of seven fields fundus photographs. The presence and severity of DR were analyzed for possible correlations to non-genetic and genetic dispositions.RESULTS： A total of 1438 participants with data available for analysis, the prevalence of any DR was 35.4%. The prevalence of mild non-proliferative diabetic retinopathy（NPDR）, moderate NPDR, severe NPDR, and proliferative diabetic retinopathy was 27.7%, 2.6%, 0.5% and 4.5%, respectively. By multiple logistic regression analysis, risk factors for the presence of any DR included male（P=0.031）, lower income level（P=0.011）, lower education background（P=0.022）, longer duration of diabetes（P=0.001）, younger age at diabetic onset（P=0.001）, higher systolic blood pressure（P=0.007）, higher glycosylated hemoglobin A1 c levels（P=0.001）, high albuminuria（P=0.03）, and use of insulin（P〈0.001）. For vision-threatening DR, four factors were significant： younger age at diabetic onset（P〈0.001）,higher systolic blood pressure（P=0.042）, high albuminuria（P〈0.001）, and use of insulin（P〈0.001）. CONCLUSION： The BDDES is the first large-scale ongoing cohort study of a Chinese urban population of persons with type 2 diabetes. Using standardized grading system comparable to large cohort studies from western populations, our baseline data shows that the prevalence of DR and major risk factors in this Chinese ethnic population are comparable to that found in the western population studies.

SEISMIC RISK ANALYSIS FOR OCEAN OIL PLATFORMS

The seismic risk analysis method and some special aspects concerning its application to ocean oil platforms are reviewed briefly through an example of analysis for the oil platforms in the Bohai sea. In view of the features of temporal and spatial distribution of earthquakes in China, it is emphasized that the temporal and spatial inhomogeneity of seismicity should be thoroughly studied when dealing with a specific project where a short service life and a high degree of safety are required.

Incidence,prevalence,and causes of spinal injuries in China,1990-2019:Findings from the Global Burden of Disease Study 2019

Background:Spinal injuries are an urgent public health priority;nevertheless,no China-wide studies of these injuries exist.This study measured the incidence,prevalence,causes,regional distribution,and annual trends of spinal injuries in China from 1990 to 2019.Methods:We used data from the Global Burden of Diseases,Injuries,and Risk Factors Study 2019 to estimate the incidence and prevalence of spinal injuries in China.The data of 33 provincial-level administrative regions(excluding Taiwan,China)provided by the National Center for Chronic and Noncommunicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention(CDC)were use to systematically analyze the provincial etiology,geographical distribution,and annual trends of spinal injuries.The Bayesian meta-regression tool DisMod-MR 2.1 was used to ensure the consistency among incidence,prevalence,and mortality rates in each case.Results:From 1990 to 2019,the number of living patients with spinal injuries in China increased by 138.32%,from 2.14 million to 5.10 million,while the corresponding age-standardized prevalence increased from 0.20%(95%uncertainty interval[UI]:0.18-0.21%)to 0.27%(95%UI:0.26-0.29%).The incidence of spinal injuries in China increased by 89.91%(95%UI:72.39-107.66%),and the prevalence increased by 98.20%(95%UI:89.56-106.82%),both the most significant increases among the G20 countries;71.00%of the increase could be explained by age-specific prevalence.In 2019,the incidence was 16.47(95%UI:12.08-22.00,per 100,000 population),and the prevalence was 358.30(95%UI:333.96-386.62,per 100,000 population).Based on the data of 33 provincial-level administrative regions provided by CDC,age-standardized incidence and prevalence were both highest in developed provinces in Eastern China.The primary causes were falls and road injuries;however,the prevalence and specific causes differed across provinces.Conclusions:In China,the overall disease burden of spinal injuries increased significantly during the past three decades but varied considerably according to geographical location.The primary causes were falls and road injuries;however,the prevalence and specific causes differed across provinces.

Mitochondrial DNA as a Risk Factor for False Positives in Case-Control Association Studies

During the last decade, hundreds of studies have been pub- lished examining whether significant associations exist be- tween mitochondrial DNA （mtDNA） variants and/or haplogroups （clades） and particular diseases （generally com- mon/complex diseases） （Fig. 1）. However, several authors have gathered evidence indicating a high incidence of false positive findings in mtDNA case-control association studies. Raule et al. （2007） and Herrnstadt and Howell （2004） showed various problems affecting mtDNA case-control association studies. Salas et al.

Method to assess component contribution to toxicity of complex mixtures： Assessment of puberty acquisition in rats exposed to disinfection byproducts

A method based on regression modeling was developed to discern the contribution of component chemicals to the toxicity of highly complex, environmentally realistic mixtures of disinfection byproducts（DBPs）. Chemical disinfection of drinking water forms DBP mixtures.Because of concerns about possible reproductive and developmental toxicity, a whole mixture（WM） of DBPs produced by chlorination of a water concentrate was administered as drinking water to Sprague–Dawley（S–D） rats in a multigenerational study. Age of puberty acquisition,i.e., preputial separation（PPS） and vaginal opening（VO）, was examined in male and female offspring, respectively. When compared to controls, a slight, but statistically significant delay in puberty acquisition was observed in females but not in males. WM-induced differences in the age at puberty acquisition were compared to those reported in S–D rats administered either a defined mixture（DM） of nine regulated DBPs or individual DBPs. Regression models were developed using individual animal data on age at PPS or VO from the DM study. Puberty acquisition data reported in the WM and individual DBP studies were then compared with the DM models. The delay in puberty acquisition observed in the WM-treated female rats could not be distinguished from delays predicted by the DM regression model, suggesting that the nine regulated DBPs in the DM might account for much of the delay observed in the WM. This method is applicable to mixtures of other types of chemicals and other endpoints.