Effect of crotonaldehyde exposure induced lung injury in male rats / 中国职业医学

OBJECTIVE: To observe the effect of crotonaldehyde exposure on lung injury in male rats,and to explore the mechanism of toxic action. METHODS: Specific pathogen free healthy adult male Wistar rats were randomly divided into 4groups with 10 rats in each group: a control group and low-,medium- and high-dose groups. Rats were treated with 0. 00,2. 11,4. 22,8. 44 mg / kg body weigh crotonaldehyde by intra-gastric administration,once per day for 25 consecutive days.After the last treatment,rats were secrificed and the lung was isolated. Lung organ coefficients were calculated and the pathologic changes in lung tissues were observed. The levels of interferon( IFN)-γ,interleukin( IL)-1 β,IL-4,IL-6 and tumor necrosis factor( TNF)-α in lung tissue were determined by enzyme-linked immunosorbent assay. RESULTS: The lung tissue in both the medium- and high-dose group showed early inflammatory pathological changes with alveolar structure damage,interval widened and inflammatory cell infiltration,congestion,bronchiolar epithelial hyperplasia,visible red blood cells and inflammatory cells infiltration. The changes in the high-dose group were more severe than that in the medium-dose group. The lung organ coefficient and the levels of IFN-γ,IL-1 β,IL-4,IL-6,TNF-α in lung tissue were increased in dose-effect relations( P < 0. 01). CONCLUSION: Crotonaldehyde can increase the level of inflammatory factors in the lung tissues of rats,causing inflammatory injury of lung tissue.

Influence of genetic polymorphisms of epoxide hydrolase 1 on metabolism of styrene in body / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the role of genetic polymorphisms of epoxide hydrolase 1 (EPHX1) in the metabolism of styrene in vivo.</p><p><b>METHODS</b>Fifty-six styrene-exposed workers, who worked in the painting workshop of an enterprise for manufacturing glass fiber-reinforced plastic yachts in Shandong Province, China for over one year and were protected in approximately the same way, were selected as study subjects. The 8-hour time-weighted average concentration (8 h-TWA) of styrene and the concentrations of mandelic acid (MA) and phenyl glyoxylic acid (PGA) as urinary metabolites were measured. The genetic polymorphisms of EPHX1 were detected by polymerase chain reaction-restriction fragment length polymorphism analysis.</p><p><b>RESULTS</b>The urinary concentrations of MA and PGA were 177.25±82.36 mg/g Cr and 145.91±69.73 mg/g Cr, respectively, and the 8 h-TWA of styrene was 133.28±95.81 mg/m3. Urinary concentrations of MA and PGA were positively correlated with 8 h-TWA of styrene (R=0.861, P < 0.05; R=0.868, P < 0.05). The subjects were divided into high-exposure group (8 h-TWA >50 mg/m(3)) and low-exposure group (8 h-TWA ≤ 50 mg/m(3), and in the two groups, the urinary concentrations of MA and PGA were significantly higher in the individuals carrying high-activity genotypes of EPHX1 than in those carrying low-activity genotypes of EPHX1 (P < 0.05).</p><p><b>CONCLUSION</b>Genetic polymorphisms of EPHX1 play an important role in the metabolic process of styrene in vivo.</p>

The increase of micronuclei frequencies of peripheral blood lymphocyte in plywood workers exposed accumulatively to formaldehyde / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of occupational exposure to formaldehyde on the micronuclei frequencies in peripheral blood lymphocytes of workers.</p><p><b>METHODS</b>Two hundred thirty six plywood workers were divided into 3 exposure groups (low, middle and high) according to internal exposure biomarker (formaldehyde human serum albumin conjugate, FA-HSA), which was detected by ELISA. The concentrations of formaldehyde (FA) in air of two workshops were measure using the high performance liquid chromatography. Cytokinesis-block micronucleus (CBMN) test was used to detect the micronuclei frequencies of peripheral blood lymphocyte in 236 workers.</p><p><b>RESULTS</b>The average concentrations of FA in the low and high exposure workshops were 0.58 +/- 0.20 and 1.48 +/- 0.61 mg/m3, respectively, there was significant difference (P < 0.01). The average concentrations of serum FA-HAS of workers in two workshops were 69.22 +/- 15.37 and 136.29 +/- 89.49 pg/ml, respectively, there was significant difference (P < 0.01). The results of CBMN test showed that the micronucleus frequencies in low, middle and high exposure groups were 1.94 +/- 1.72, 2.10 +/- 1.92 and 2.10 +/- 1.70 per thousand, respectively, there were no significant differences between groups. However, the micronucleus frequencies in accumulative low, middle and high exposure groups were 1.36 +/- 1.36, 2.31 +/- 1.81 and 2.49 +/- 1.92 per thousand, respectively, there were significant differences between different accumulative exposure groups (P < 0.01). The results of correlation analysis indicated that there was a positive correlation between accumulative exposure levels and micronucleus frequencies (r(s) = 0.321, P < 0.01). The accumulative exposure doses may be a risk factor for high micronucleus frequencies in workers exposed to FA (P(trend) = 0.002).</p><p><b>CONCLUSION</b>FA-HSA levels can serve as an internal exposure biomarker for assessing the exposure level of workers exposed to FA. Accumulative formaldehyde exposure resulted in an increase of micronuclei frequencies of peripheral blood lymphocyte in plywood workers.</p>

Meta-analysis of association of tumor necrosis factor alpha and transforming growth factor beta gene polymorphisms with pneumoconiosis / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To evaluate the relationship between tumor necrosis factor-alpha-238, transforming growth factor beta (509 and 869) gene polymorphisms and pneumoconiosis susceptibility.</p><p><b>METHODS</b>We searched published full-text from foreign language databases including Elsevier, PubMed, Wiley Online Library, EMCC, Web of Science, chinese databases containing CNKI, VIP, Wanfang, CBM and Cochrane library to collect case-control or cohort study on gene gene polymorphisms said above with pneumoconiosis susceptibility from the year January1988 to August 2011. 28 relevant articles were selected and 20 of them met the criteria. The correlated index was extracted for aggregate analysis in RevMan 4.2.</p><p><b>RESULTS</b>Among the 20 studies, 10 articles on TNF-α238 polymorphism (including 2232 pneumoconiosis cases and 1985 control subjects), 4 articles on TGF-β509 polymorphism (including 693 pneumoconiosis cases and 663 control subjects), and 6 articles on TGF-β869 polymorphism (including 1450 pneumoconiosis cases and 1101 control subjects) were included in the current study. Meta-analysis results showed that there was a significant association between TNF-α238 polymorphism and pneumoconiosis: the population with GA and AA genotypes of TNF-α238 had higher risks to pneumoconiosis (OR = 1.53, 95%CI: 1.25 ∼ 1.88) comparing to GG genotype, and the population with A allele had higher risks to pneumoconiosis comparing to allele G (OR = 1.64, 95%CI: 1.17 ∼ 2.30). The stratified analysis showed that the people with GA and AA genotypes and A allele who were silicosis, Asian or exposed to dust had higher risks to pneumoconiosis (OR = 2.14, 95%CI: 1.20 ∼ 3.82; OR = 2.16, 95%CI: 1.20 ∼ 3.88; OR = 1.78, 95%CI: 1.01 ∼ 3.11; OR = 1.83, 95%CI: 1.04 ∼ 3.22; OR = 1.80, 95%CI: 1.21 ∼ 2.66; OR = 1.50, 95%CI: 1.23 ∼ 1.83). No significant association was found between TGF-β (509 and 869) gene polymorphisms with pneumoconiosis: In contrast to the CC genotype, the population who had CT and TT genotypes had no higher risks to pneumoconiosis (OR = 1.56, 95%CI: 0.81 ∼ 3.01; OR = 0.96, 95%CI: 0.79 ∼ 1.18); The population who had T allele had no higher risks to pneumoconiosis in contrast to the C allele (OR = 1.35, 95%CI: 0.86 ∼ 2.13; OR = 1.02, 95%CI: 0.91 ∼ 1.15).</p><p><b>CONCLUSION</b>Significant association was found between TNFα238 gene polymorphism and pneumoconiosis; and TGF-β (509 and 869) were not.</p>