OBJECTIVEOur objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects.

METHODSWe built a function with different parameters to describe the effects of trace elements on neural tube defects. The association between neural tube defects and trace element levels was transformed into an optimization problem using the maximum likelihood method.

RESULTSTin, lead, nickel, iron, copper, and aluminum had typical layered effects (dosage effects) on the prevalence of neural tube defects. Arsenic, selenium, zinc, strontium, and vanadium had no effect, and molybdenum had one threshold value that affected the prevalence of birth defects.

CONCLUSIONAs an exploratory research work, our model can be used to determine the direction of the effect of the trace element content of cultivated soil on the risk of neural tube defects, which shows the clues by the dosage effect of their toxicological characteristics. Based on our findings, future biogeochemical research should focus on the direct effects of trace elements on human health.

China ; epidemiology ; Dose-Response Relationship, Drug ; Environmental Exposure ; Female ; Humans ; Metals ; chemistry ; toxicity ; Models, Biological ; Neural Tube Defects ; chemically induced ; epidemiology ; Pregnancy ; Prevalence ; Soil Pollutants ; chemistry ; toxicity ; Trace Elements ; chemistry ; toxicity

Objective To investigate the comorbidity of hepatic cystic echinococcosis with HBV/HCV infection, liver cirrhosis, and hepatocellular carcinoma, and to lay a foundation for further research on the influence of hepatic cystic echinococcosis on HBV/HCV infection, liver cirrhosis, and hepatocellular carcinoma. Methods A retrospective analysis was performed for the data of 401 patients with hepatic cystic echinococcosis who were admitted to The First Affiliated Hospital of Shihezi University from 2003 to 2019, and the state of comorbidity of hepatic cystic echinococcosis with HBV/HCV infection, liver cirrhosis, and hepatocellular carcinoma was clarified. The patients with hepatic cystic echinococcosis and chronic HBV/HCV infection were selected as comorbidity group, and the patients with HBV/HCV infection alone were matched as control group. The chi-square test and the Fisher's exact test were used to analyze the state of viral infection and the disease composition of liver cirrhosis and hepatocellular carcinoma. Results Of all 401 patients, 38(9.5%) were included in the comorbidity group and 2(0.5%) had liver cirrhosis after HBV/HCV infection, while no patient had hepatocellular carcinoma after HBV/HCV infection. Among the patients with chronic hepatitis B virus infection in the comorbidity group, non-active HBsAg carriers accounted for 81%, HBeAg-positive chronic hepatitis B patients accounted for 9.5%, and HBeAg-negative chronic hepatitis B patients accounted for 9.5%; among the patients with hepatitis B virus infection in the control group, non-active HBsAg carriers accounted for 43%, HBeAg-positive chronic hepatitis B patients accounted for 33%, and HBeAg-negative chronic hepatitis B patients accounted for 19%, with a significant difference between the two groups ( P =0.033). There was a significant difference in the HBV RNA clearance rate of the patients with HCV infection between the comorbidity group and the control group ( χ 2 =4.447, P =0.035). In the comorbidity group, the patients with liver cirrhosis accounted for 5.2% and there were no patients with hepatocellular carcinoma, while in the control group, the patients with liver cirrhosis accounted for 18.4% and those with hepatocellular carcinoma accounted for 5.2%; the comorbidity group had significantly lower proportions than the control group ( P =0.048). Conclusion The proportion of liver cirrhosis patients with hepatic cystic echinococcosis and HBV/HCV infection is lower than that of liver cirrhosis patients with viral hepatitis alone, and there are no cases of hepatocellular carcinoma after HBV/HCV infection. Further multicenter studies are needed to investigate the influence of hepatic cystic echinococcosis on chronic HBV/HCV infection, liver cirrhosis, and hepatocellular carcinoma.