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Arsenic (As) and fluoride (F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, leading to cognitive, learning, and memory impairments. However, early biomarkers of learning and memory impairment induced by As and/or F remain unclear. In the present study, the mechanisms by which As and/or F cause learning memory impairment are explored at the multi-omics level (microbiome and metabolome). We stablished an SD rats model exposed to arsenic and/or fluoride from intrauterine to adult period. Arsenic and/fluoride exposed groups showed reduced neurobehavioral performance and lesions in the hippocampal CA1 region. 16S rRNA gene sequencing revealed that As and/or F exposure significantly altered the composition and diversity of the gut microbiome, featuring the Lachnospiraceae_NK4A136_group, Ruminococcus_1, Prevotellaceae_NK3B31_group, [Eubacterium]_ xylanophilum_group. Metabolome analysis showed that As and/or F-induced learning and memory impairment may be related to tryptophan, lipoic acid, glutamate, gamma-aminobutyric acidergic (GABAergic) synapse, and arachidonic acid (AA) metabolism. The gut microbiota, metabolites, and learning memory indicators were significantly correlated. Learning memory impairment triggered by As and/or F exposure may be mediated by different gut microbes and their associated metabolites. [ABSTRACT FROM AUTHOR]

Vinyl chloride (VC) is a common industrial organic chlorine and environmental pollutant. In recent years, the dietary structure of residents especially Chinese has gradually shifted to western dietary patterns. VC aggravates dietary fatty acid-induced hepatic steatosis, but its mechanism is still unclear. And if the risk factors for steatosis persist, more severe diseases such as fibrosis and cirrhosis will occur. Therefore, we studied the effects and mechanisms of VC (160 and 800 mg/m 3 ) and its metabolite (chloroacetaldehyde, 2.25, 4.5, and 9 μM) on hepatic steatosis of high-fat diet (HFD)-fed mice and palmitic acid (PA, 100 μM) treated HepG2 cells. Liver and serum biochemical indicators and pathological staining of the liver showed that the hepatic steatosis of VC combined with HFD groups was more severe than that of single-exposure groups (HFD group, low-dose VC group, and high-dose VC group). Moreover, VC enhanced HFD-induced oxidative stress (OS) and endoplasmic reticulum stress (ERS) and further upregulated the expression of sterol regulatory element-binding protein 1 (SREBP-1) and FAS. Besides, antioxidants and ERS inhibitors reduced the steatosis of HepG2 cells induced by VC metabolites and PA. These results suggest that VC exposure can enhance the degree of hepatic steatosis in HFD-fed mice. VC combined with HFD led to OS and ERS and upregulated the expression of de novo lipogenesis-related proteins, which may be related to the occurrence of hepatic steatosis. And the increased expression of CYP2E1 induced by VC combined with HFD may be the cause of OS., (© 2021 John Wiley & Sons, Ltd.)

Objective: To explore the association between chromosomal damage induced by vinyl chloride monomer (VCM) and polymorphisms of xenobiotic metabolism genes and DNA repair genes., Methods: Cytokinesis-block micronucleus (CBMN) test was performed to detect chromosomal damage in peripheral lymphocytes of 402 VCM-exposed workers. Multiplex PCR was used to simultaneously amplify GSTM1 and GSTT1 genes, other genetic polymorphisms were performed using a PCR-RFLP technique., Results: Multiple (adjusted) Poisson regression analysis showed that mean MN frequencies were significantly elevated for the intermediate (4000-40000 mg) and high (> 40000 mg) exposure groups as compared with the low exposure group (P = 0.003 and 0.03, respectively). For genetic polymorphisms, the exposed workers with CYP2E1 or XRCC1 Arg280His variance showed a higher CBMN frequency than their wild-type homozygous counterparts (P = 0.02); so did the workers with GSTP1 105Val/Val genotype or ALDH2 504Glu/Glu genotype than those with a combination of other genotypes (P = 0.01 and 0.003, respectively)., Conclusion: Our findings reveal that cumulative exposure dose of VCM and common genetic variants in genes, such as GSTP1, CYP2E1, ALDH2, XRCC1 Arg280His genotypes, are the major factors that modulate MN induction in VCM- exposed workers. Further study to investigate the relationship between individual characteristics and genetic susceptibility to VCM-caused chromosome damage is warranted, it is helpful for us to understand the mechanism of VCM metabolism, to find the biomarkers of susceptibility and to recognize the susceptible individuals in the primary prevention of VCM-caused damage.

Objective: To survey the sleep habits (bedtime, wake time), sleep duration, and sleep problems in school-age children of China., Method: From November to December, 2005, a total of 19,299 school-age children from 55 elementary schools of 9 cities entered the study by a cross-sectional survey. A parent-administered questionnaire and the Chinese version of the Children's Sleep Habits Questionnaire were applied to investigate children's sociodemographic characteristics and sleep behaviors, respectively., Results: The mean sleep duration was 9 hours and 10 minutes (9:10, SD:48 min) during the weekdays and 9:48 (SD: 63 min) during the weekends. In about 71.4% and 41.8% school-aged children the sleep duration per day did not reach the lowest criterion of 10 hours recommended by the Ministry of Education of China during weekdays and weekends, respectively. Sleep problems were common with prevalence ranging from 14.5% for sleep-disordered breathing to 75.3% for daytime sleepiness. Parasomnia (chi(2) = 13.76, P < 0.01) and sleep-disordered breathing (chi(2) = 119.83, P < 0.01) were more prevalent in boys than in girls; however, sleep anxiety was more prevalent in girls than in boys (chi(2) = 19.42, P < 0.01). Except for night waking, other types of sleep problems were significantly associated with age., Conclusions: Inadequate sleep duration and sleep problems prevail among school-age children, which indicates that children's sleep health may be a major public health concern in China.

Objective: To explore the relationship between polymorphisms of FAS and FASL genes and genetic susceptibility of silicosis., Methods: A case-control study was conducted. The case group was 183 male patients with silicosis and the control group was 111 male silica-exposed but without silicosis miners. Data on total dust concentrations was collected to estimate cumulative total dust exposure (CTE) of each subject and each person's characteristics and work history were obtained from questionnaire. Polymerase chain reaction re-strained fragment length polymorphism technique (PCR-RFLP) was applied to detect the single nucleotide polymorphisms (SNPs) of FAS-1377, FAS-670 and FASL-844. Associations between polymorphisms and risk of silicosis and stages, interactions between polymorphisms, between polymorphisms and CTE and smoking and haplotypes were analyzed., Results: There were no differences in the FAS-1377, FAS-670 and FASL-844 genotypes between the case group and the control group (P > 0.05). No association was observed between FAS-1377, FAS-670 and FASL-844 polymorphisms and silicosis and stages (P > 0.05). The frequencies of FAS-1377G/-670G haplotype in the cases (9.6%) were higher than those in the controls (3.6%) (P < 0.05). No interactions between the polymorphisms of different genes, the gene polymorphism and the total accumulative total dust, the gene polymorphism and smoking were observed (P > 0.05)., Conclusion: FAS-1377, FAS-670 and FASL-844 polymorphisms are not susceptible factors of silicosis. The FAS-1377G/-670G haplotype might be a susceptibility marker of silicosis.

Objective: To explore the relationship between genetic polymorphism of P53, P21, CCND1 and susceptibility of chromosomal damage induced by vinyl chloride monomer (VCM)., Methods: 183 workers occupationally exposed to VCM were involved in our study. Cytokinesis-block micronucleus (CB-MN) assay was used to detect chromosome damage in peripheral lymphocyte. PCR-RFLP technique was applied to detect polymorphisms in P53 gene (exon4, intron3 and intron6), P21 gene (exon2 and exon3) and CCND1 (exon4)., Results: The risk of chromosomal damage for VCM-exposed workers with more than 30 yr was 1.2202 (95% CI: 1.0580 approximately 1.4072, P = 0.0062) compared with the younger workers, and the risk of female workers was 1.1491 (95% CI: 0.9841 approximately 1.3416, P = 0.0772) compared with male workers. The MN frequency in subjects with P53 intron6 mutant homozygous and heterozygous was higher than their wild-type homozygous counterparts (OR = 1.3032, 95% CI: 1.1285 approximately 1.6405, P = 0.0285). P53 exon4, intron3 and intron6 haplotype pairs of BBB/AAA and BAB/AAA were associated with the increased frequencies of micronucleus., Conclusion: Among VCM-exposed workers, more than 30ys, female, carrying P53 intron6 mutated allele and BBB/AAA and BAB/AAA haplotype pairs have higher risk of chromosomal damage.

Objective: To develop the Chinese version of Children's Sleep Habits Questionnaire (CSHQ) by translating and retranslating the English version of CSHQ and to examine the reliability, content validity, construct validity of the Chinese version in a general population of school-age children., Methods: During November and December 2005, a total of 20 457 school-age children from 55 primary schools of 9 cities were recruited through cluster-stratified selection, using geographic location, economic standard, and population density as criteria. A parent-administered questionnaire and the Chinese version of CSHQ were completed to quantify sociodemographic characteristics and to characterize sleep patterns and sleep disturbances, respectively., Results: The internal consistency of overall questionnaire and the eight subscales of the Chinese version of CSHQ was good (Cronbach's alpha coefficient was 0.73 and ranged from 0.42 to 0.69, respectively). The consistency between mother and father was ICCs = 0.89 for overall questionnaire and ranged from ICCs = 0.83 to ICCs = 0.92 for subscales. The test-retest reliability was ICCs = 0.85 for overall questionnaire and range from ICCs = 0.60 to ICCs = 0.88 for subscales. Factor analysis revealed a three-factor structure, which could represent bedtime behavior problems, sleep disturbance, sleep duration and daytime sleepiness, respectively, and the three factors could be used to explain 58.63% of the total variance. The factor loading was above 0.5 for the corresponding subscale., Conclusions: Reliability, content validity and construct validity of the Chinese version of CSHQ in a general population of school-age children are good. It appears to be a suitable instrument for measuring sleep patterns and screening for sleep problems in school-aged children.