DNA methylation levels of genome in cFb transdifferentiation induced by SiO2 in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the DNA methylation levels of genome in cFb transdifferentiation induced by SiO2 in rats.</p><p><b>METHODS</b>The primary macrophages and fibrocytes of SD rats were co-cultured directly and indirectly, which were exposed to SiO2 at the doses of 25, 50 and 100 g/ml. The transdifferentiation of cFb was identified with immunohistochemical assay. The genomic DNA methylation levels of cFb were detected with HPLC.</p><p><b>RESULTS</b>Under the condition of indirect co-culture, as compared with control group, the genomic DNA methylation levels of cFb exposed to SiO2 at the doses of 25, 50 and 100 g/ml reduced by 19.9%, 26.9% and 30.3%, respectively (P < 0.05); as compared with cFb exposed to 100 g/ml SiO2, the genomic DNA methylation levels of cFb exposed to 5-aza-dC decreased by 22.0% (P < 0.05). Under the condition of ThinCert(TM) direct co-culture, as compared with control group, the genomic DNA methylation levels of cFb exposed to SiO2 at the doses of 25, 50 and 100 g/ml reduced by 22.2%, 30.2% and 36.7%, respectively (P < 0.05); as compared with cFb exposed to 100 g/ml SiO2, the genomic DNA methylation levels of cFb exposed to 5-aza-dC decreased by 20.6% (P < 0.05).</p><p><b>CONCLUSION</b>Under the co-culture condition in vitro, SiO2 could reduce the genomic DNA methylation levels of cFb. The ThinCert(TM) direct co-culture can be used to study the silicosis fibrosis.</p>

A meta-analysis of susceptibility to pneumoconiosis and polymorphism of tumor necrosis factor-α 308 and 238 locus / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the relationship between the polymorphism of TNF-α gene 308, 238 locus and the susceptibility to pneumoconiosis.</p><p><b>METHODS</b>Eighteen published case-control studies about TNF-α gene 308, 238 locus polymorphism and pneumoconiosis susceptibility were searched out from sino-foreign databases from January 1994 to December 2010. Meta-analysis was applied on the published research to calculate the pooled OR value (95%CI) and stratified analyze the types and species of pneumoconiosis.</p><p><b>RESULTS</b>Eleven of the published research articles were selected into the analysis, including 10 research focusing on TNF-α gene 308 locus, with 1408 cases and 1639 controls in total. The meta-analysis showed that comparing with Gln/Gln carriers, Arg/Arg, Arg/Gln, Gln/Arg + Arg/Arg carriers were 1.89-fold (95%CI: 1.10 - 3.24), 1.53-fold (95%CI: 1.25 - 1.87), and 1.56-fold (95%CI: 1.28 - 1.90) more susceptible to pneumoconiosis, respectively. The stratified analysis showed that among coal workers, the TNF-α gene 308 locus Arg/Arg, Arg/Gln, Gln/Arg + Arg/Arg carriers were separately 2.29-fold (95%CI: 1.22 - 4.29), 1.56-fold (95%CI: 1.20 - 2.03), 1.64-fold (95%CI: 1.28 - 2.11) more susceptible to pneumoconiosis than Gln/Gln carriers; and among Asian people, the TNF-α gene 308 locus Gln/Arg, Gln/Arg + Arg/Arg carriers were separately 1.58-fold (95%CI: 1.28 - 1.95) and 1.57-fold (95%CI: 1.28 - 1.94) more susceptible to pneumoconiosis than the Gln/Gln carriers. Four case-control research focus on the study of TNF-α gene 238 locus, including 391 cases and 391 controls in total. The analysis showed that comparing with the non-carriers, TNF-α gene 238 locus Arg/Arg, Arg/Gln, Gln/Arg + Arg/Arg carriers were 6.03-fold (95%CI: 1.35 - 26.97), 1.87-fold (95%CI: 1.07 - 3.30) and 2.36-fold (95%CI: 1.37 - 4.07) more susceptible to pneumoconiosis.</p><p><b>CONCLUSION</b>TNF-α gene 308, 238 locus Arg/Arg, Gln/Arg, Gln/Arg + Arg/Arg carriers are more susceptible to pneumoconiosis.</p>

Long term observation in effects of potassium and calcium supplementation on arterial blood pressure and sodium metabolism in adolescents with higher blood pressure / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of potassium and calcium supplementation in table salt on reduction of arterial blood pressure and sodium metabolism in adolescents with higher blood pressure.</p><p><b>METHODS</b>A single blind placebo-controlled trial was carried out for two years in 220 adolescents with higher blood pressure, aged 18 - 22 years, who were randomly divided into supplementary group (n = 110) and control group (n = 110). Each of the subjects in the supplementary group and their family members was given 10 mmol of potassium and 10 mmol of calcium mixed in their table salt daily for 24 months.</p><p><b>RESULTS</b>Night urinary sodium and potassium excretion increased (urinary Na(+), P < 0.05; urinary K(+), P < 0.01) and blood pressure lowered by 5.3 mm Hg/1.8 mm Hg in average from the baseline in the supplementary group two years after potassium and calcium supplementation, as compared with that in the control group increased by (1.3/1.7) mm Hg.</p><p><b>CONCLUSIONS</b>Adequate supplement of potassium and calcium in daily table salt intake was an effective way to prevent form hypertension and could promote their urinary sodium excretion and reduction of arterial blood pressure in adolescents with higher blood pressure.</p>