RESUMO
Risk assessment is a necessary technical means to protect human health and environmental safety. Traditional risk assessment based on toxicity data obtained from animal experiments was difficult to meet the need for risk assessment for a large number of chemicals due to the low throughput, long cycle, high cost and uncertainty of extrapolation to human exposure dose. The proposed risk assessment frameworks, the model of action (MOA) and the adverse outcome pathway (AOP), pointed the way for us to develop new and efficient evaluation methods. In this review, the basic concepts and contents of MOA and AOP, as well as the relationship between them, were introduced. Taking acrylamide (AA) as an example, this review briefly described the application of MOA/AOP framework in chemical risk assessment, so as to provide theoretical guidance for better application of MOA/AOP framework in chemical risk assessment.
RESUMO
OBJECTIVE: To establish a method for simultaneous determination of 1,1,1-trichloroethane(TCA) and 1,1,2-TCA in the workplace air by solvent desorption-gas chromatography. METHODS: The 1,1,1-TCA and 1,1,2-TCA in the workplace air were collected by activated carbon tube and desorbed with carbon disulfide. They were separated with DB-1(100.0% dimethyl polysiloxane) capillary column and detected by flame ionization detector. RESULTS: The good linear ranges of 1,1,1-TCA and 1,1,2-TCA were 1.340-1.338×10~4 and 1.440-1.442×10~4 mg/L, respectively. The correlation coefficients were greater than 0.999, with the detection limits of 0.100 and 0.140 mg/L, respectively. The average desorption efficiencies of 1,1,1-TCA and 1,1,2-TCA were 98.6%-99.6% and 94.9%-96.2%. The within-run and between-run relative standard deviations were 0.4%-0.9% and 0.5%-1.1%, respectively. The samples could be stored at room temperature for at least 14 days. CONCLUSION: This method has high desorption efficiency and sensitivity, good precision and simple operation, which is suitable for simultaneous detection of 1,1,1-TCA and 1,1,2-TCA in the workplace air.
RESUMO
Objective To explore the clinical manifestation, imaging examination, treatment and prognosis of Alagille syndrome in a child combined with hepatocellular carcinoma. Method The clinical manifestation, assistant examination and diagnosis of Alagille syndrome combined with hepatocellular carcinoma were analyzed in the child, and the pertinent literature were reviewed. Results The 6-year-old girl was admitted to hospital for repeated jaundice, and had a history of cardiac surgery. After admission, the patient was found to have a typical face look such as frontal bossing, sunken eyes, pointed chin and hypertrophy of nasal tip. Blood biochemistry showed intrahepatic cholestasis and increased alpha-fetoprotein. Abdominal ultrasonography revealed diffuse multiple solid lesions in the liver. And magnetic resonance imaging of the liver indicated that the liver was enlarged and multiple solid space occupying masses. Jagged 1 gene detection showed heterozygosis mutation of c.1205delC. Conclusion Alagllie syndrome complicated with hepatocellular carcinoma in childhood is extremely rare, and early diagnosis and long-term follow-up are of positive significance for its treatment and prognosis.
RESUMO
Objective@#To investigate the value of DNA content in comet tail (TailDNA) in predicting the changes in peripheral blood cell counts in workers exposed to benzene.@*Methods@#In 2011, cluster sampling was used to select 150 male workers exposed to benzene in a petrochemical factory. Cubital venous blood and urine samples were collected for routine blood rest, comet assay, and measurement of s-phenylmercapturic acid (SPMA) and urine creatinine. The population was divided into groups according to urinary SPMA or TailDNA, and routine blood test results within 3 years were collected to analyze the changes in blood cell counts.@*Results@#The low-SPMA group had significantly higher white blood cell and neutrophilcounts in all years than the high-SPMA group (P<0.05) . The low-Tail DNA group had a significant increase in platelet count from 2012 to 2014 (P<0.05) , while the high-Tail DNA group had no significant change (P>0.05) . During the 4-year period, the high-TailDNA group had a significantly lower red blood cell count than the low-TailDNA group (P<0.05) . The high-TailDNA group showed a gradual reduction in white blood cell count over time (β=-0.113, P<0.05) , and the low-TailDNA group showed no trend of the reduction in white blood cell count (P>0.05) .@*Conclusion@#TailDNA can be used to predict the changes in blood cell counts in workers exposed to benzene.
RESUMO
Objective To investigate the effects of immune system and immuno-related miRNAs expression in low-dose benzene and its homologue mixed-exposed workers in a short time. Methods A total of 40 workers were recruited from a petrochemical factory ,and their blood samples were collected before and after work to detect the levels of IgA,IgG,IgM,IFN-γ,IL-1β,IL-2,IL-8,TNF-αin serum and miRNA-146a,-155 expression in the peripheral blood mononuclear cell. In the meanwhile ,we measured the individual benzene and its homologue exposure level of recruited workers. Results According to the concentration of benzene ,the subjects were divided into benzene-exposed group(20 workers)and control group(20 workers). And toluene exposure level in benzene-exposed group was significantly higher than that in control group(P<0.05). Significant decrease of IgG was found in benzene-exposed workers after one work shift,compared with control group(P<0.05). Moreover,the interaction between benzene and toluene was significant correlated with the decrease of IL-1β and TNF-α(P < 0.05). Additionally,the interaction between miRNA-155 and miRNA-146a was significant correlated with the decrease of TNF-α(P<0.05). Conclusions:Occupational exposure to low-dose benzene and toluene in a short time could decrease immune function. And there may be an effect of miRNAs in the regulation of cytokine.
RESUMO
ObjectiveTo study the risk factors of childhood functional constipation.MethodsA cross-sectional analysis of risk factors associated with 182 cases of functional constipation in children was conducted from March 2013 to February 2014. ResultsThe male patients were more than females, mainly in preschool children. The risk factors were did not like fruits and vegetables (52.2%), drank less water (44.0%), did not develop the habit of daily bowel movement (39.5%), defecation fear (36.3%), inadequate food intake (25.8%). There were different risk factors in different age stages.ConclusionsFunctional constipation is related to gender, age, diet habits and mental psychology.
RESUMO
Current occupational health and occupational medicine teaching content focused on the detection of harmful factors,and more belonged to validation experiments.Closed-end management of experimental teaching,experimental report-based performance evaluation methods and single model of teaching methods reduced the students' study interesting,lack of problem-solving abilities.Therefore,it is necessary to optimize the experimental curriculum,adopt an open experimental teaching,build a reasonable experimental evaluation system and promote the diversification of teaching model.