Study on the association between maternal urinary phthalate metabolites and testicular steroid hormones in the cord blood in a Chinese population / 中华预防医学杂志

<p><b>OBJECTIVE</b>The purposes of our study were to investigate the association between maternal urinary phthalate metabolites and the levels of inhibin B (INHB) and insulin-like factor 3 (INSL3) in the cord blood in a Chinese pregnant population.</p><p><b>METHODS</b>Maternal urine samples in the third trimester of pregnancy of 69 participants were collected and stored, and the samples of cord blood (10 ml) were collected at delivery between June 2011 and September 2012 in a comprehensive hospital of gynecology and obstetrics in Tianjin, China.Four phthalate metabolites, monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobutyl phthalate (MBP), and mono-2-ethylhexyl phthalate (MEHP) were measured in the urine samples using liquid chromatography-tandem mass spectrometry. The levels of INHB, INSL3 in the cord blood were tested by ELISA. Associations of phthalate exposure with INHB and INSL3 levels were determined by spearman correlation and multiple regression model analysis.</p><p><b>RESULTS</b>The median concentrations of observed metabolites in descending order were 49.74 µg/L for MMP, 24.96 µg/L for MEHP, 19.52 µg/L for MEP and 17.73 µg/L for MBP. The median concentrations of INHB and INSL3 were 89.09 and 106.21 ng/L.Significant negative associations between INHB and MMP(β' = -0.252), MEP(β' = -0.363) or the sum value (∑PAEs) (β' = -0.346) were found by the multiple regression model analysis. For INSL3, only the sum value (β' = -0.313) was inversely significantly associated with the levels of INSL3 in the cord blood.</p><p><b>CONCLUSIONS</b>Maternal urinary phthalate metabolites were associated with INHB and INSL3 in the cord blood in a Chinese population.</p>

Effects of nanosized cadmium sulfide on male reproductive system in mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of nanosized cadmium sulfide (nano-CdS) on the male reproductive system in mice.</p><p><b>METHODS</b>Thirty-six specific pathogen?free male ICR mice were equally and randomly divided into three groups: two experimental groups and a control group. The two experimental groups were exposed to 100 mg/kg and 50 mg/kg nano-CdS once daily by gavage, respectively, while the control group was exposed to the same volume of physiological saline once daily by gavage. After 45 days, levels of cadmium accumulation and serum testosterone in the testis were determined, the epididymal sperm count, the rate of sperm abnormality, and histopathological changes in testis tissue were observed under a microscope, and the level of CYP11A1 mRNA was determined by qRT-PCR.</p><p><b>RESULTS</b>Compared with the control group, the two experimental groups had a significantly increased level of cadmium accumulation in the testis (P < 0.05), and the 100 mg/kg nano-CdS group had a significantly decreased epididymal sperm count (P < 0.05) and a significantly increased rate of sperm abnormality (P < 0.05), but the 50 mg/kg nano-CdS group did not. The 100 mg/kg nano-CdS group showed different histopathological changes in testis tissue, but the 50 mg/kg nano-CdS group did not. The two experimental groups had significantly reduced levels of testosterone and CYP11A1 mRNA compared with the control group.</p><p><b>CONCLUSION</b>Nano-CdS given through the digestive tract may have an effect on the male reproductive system in mice by affecting the key enzyme genes in the androgen synthesis pathway to reduce the levels of reproductive hormones.</p>