Effect of benzene on sperm DNA / 中华男科学杂志

<p><b>OBJECTIVE</b>To assess the effect of benzene on sperm DNA.</p><p><b>METHODS</b>Twenty-seven workers exposed to benzene for over two years were included in the experiment group and 35 unexposed ones were chosen as controls. Damage by benzene on sperm DNA was detected by modified single cell gel electrophoresis (SCGE).</p><p><b>RESULTS</b>The benzene concentration in the air of the workplace of the exposed workers was (86.49 +/- 2.83) mg/m3, twice that of the national maximum allowance (40 mg/cm3). Urinary, trans-muconic acid in the exposed group was (1.40 +/- 0.62) mg/L (n = 27), significantly higher than that of the controls [(0.82) +/- 0.16) mg/L, n = 35]. After SCGE, the percentage of head DNA in the exposed group [(70.18% +/- 7.36%, n = 13 ] was significantly lower than that of the controls (90.62% +/- 2.94%, n = 16), P < 0.001.</p><p><b>CONCLUSION</b>Higher concentration of benzene could cause damage to the sperm DNA of the workers exposed to it.</p>

Detection of numerical aberrations of chromosomes 7 and 8 in sperms of workers exposed to benzene series by two-color fluorescence in situ hybridization / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the frequency of numerical aberrations for chromosomes 7 and 8 in the sperms of workers exposed to benzene series.</p><p><b>METHODS</b>Numerical aberrations in the sperms of workers were detected by two-color fluorescence in situ hybridization with biotin labeled chromosome 7 probe (D7Z1) and digoxingenin labeled chromosome 8 probe (D8Z1).</p><p><b>RESULTS</b>The time-weight average air concentration (TWA) of benzene in the workshop was 42.29 mg/m(3), which was significantly higher than that of the national maximum allowable concentration [6 mg/m(3)]. The concentration of urinary trans,trans-muconic acid(ttMA) in the exposed group was also higher than that of the control group. In all, 155721 sperm nuclei from 15 workers in the exposed group and 123771 sperm nuclei from 12 individuals in the control group were examined. The results showed that the frequency of diploidy sperms and the frequencies of disomic sperm for chromosomes 7 and 8 in the exposed group (0.129%, 0.170%, 0.078%) were significantly higher than those of the control group (0.055%, 0.053%, 0.033%), respectively. The frequencies of nullisomic sperm for chromosomes 7 and 8 in the exposed group (0.165%, 0.088%) were also significantly increased, compared with those of the control group (0.056%, 0.029%). A statistically significant difference in the frequency of overall numerical chromosome aberrations was seen between the exposed group (0.745%) and the control group (0.289%).</p><p><b>CONCLUSION</b>The results suggested that higher concentration of benzene may induce higher frequencies of numerical aberrations in the sperms of workers exposed to benzene series.</p>

Freezing effect on sperm DNA / 中华男科学杂志

<p><b>OBJECTIVES</b>To assess the effect of freezing on the sperm DNA.</p><p><b>METHODS</b>To assess the sperm DNA preserved at -80 degrees C by using the single cell gel electrophoresis (SCGE).</p><p><b>RESULTS</b>There was no statistical difference on the time factor by analysis of variance (ANOVA).</p><p><b>CONCLUSIONS</b>Integrity of sperm DNA could not be devastated in frozen states.</p>