Status and associated factors of recreational drug use among man who have sex with man in Nanjing / 中华疾病控制杂志

Objective To understand the prevalence of synthetic drug use among man who have sex with man (MSM) in Nanjing and the associated factors. Methods MSM were recruited by snow-ball sampling, peer recommendation and network recruitment. Multivariate logistic regression analysis was performed to evaluate the correlated factors of recreational drug use. Results 29.6% of the 876 MSM ever used recreational drugs. The prevalence of HIV and syphilis infections were 9.5% and 9.0% respectively. After controlling the influence of correlated factors, recreational drug use was correlated with unprotected anal intercourse in the past 6 months(OR=1.83, 95% CI: 1.35-2.47, P<0.001), multiple male sex partnership in the past 6 months(OR=2.25, 95% CI: 1.65-3.05, P<0.001), higher HIV prevalence (OR=1.95, 95% CI: 1.21-3.17, P=0.007) and higher syphilis prevalence(OR=1.71, 95% CI: 1.02-2.84, P=0.040). Multivariate Logistic analysis showed that demographic and behavioral factors associated with recreational drug use including: less than 30 years old (OR=1.50, 95% CI: 1.07-2.11, P=0.020), self-identified as homosexual orientation (OR=1.65, 95% CI: 1.16-2.34, P=0.005), seeking male partners mainly via the internet(OR=1.58, 95% CI: 1.07-2.35, P=0.022), higher monthly income(OR=1.57, 95% CI: 1.13-2.17, P=0.007), receptive sexual role(OR=1.55, 95% CI: 1.04-2.32, P=0.033). Conclusions MSM has a high prevalence of recreational drug use in Nanjing, which was positively correlated with HIV/syphilis infection and high risk behaviors. Intervention efforts should be devoted to reduce and combat drug use among MSM.

Effects of dibutyl phthalate on sertoli cells of rat testis / 中华预防医学杂志

<p><b>OBJECTIVE</b>The present study was performed to examine functional and structural impairment of rat sertoli cells following dibutyl phthalate (DBP) exposure.</p><p><b>METHODS</b>The 6-week-old healthy male Sprague Dawley rats were randomly divided into 4 groups with 16 animals in each group. DBP dissolved in peanut oil was administered by gavage at doses of 0, 250, 500 and 1 000 mg/kg. After 2-week DBP treatment, half of the rats were sacrificed. The rest were killed following 4-week DBP exposure. Follicle stimulating hormone (FSH) was analysed by radioimmunoassay. The relative expression levels of androgen binding protein (ABP) mRNA and inhibin (INH)alpha mRNA were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The sertoli cell ultrastructures were observed by using transmission electron microscope (TEM).</p><p><b>RESULTS</b>FSH levels were increased after 4-week DBP exposure with significance at doses of 250 and 1 000 mg/kg. Sperm head count and daily sperm product were decreased significantly in 500 and 1 000 mg/kg groups. The expression levels of ABP mRNA were 0.89 +/- 0.15, 0.85 +/- 0.23, 0.54 +/- 0.17, 0.52 +/- 0.16 and 0.88 +/- 0.16, 0.61 +/- 0.12, 0.48 +/- 0.15, 0.47 +/- 0.11 for 0, 250, 500 and 1 000 mg/kg after 2- and 4-week DBP treatments respectively with significance at doses of 500 and 1 000 mg/kg (P < 0.01), while the levels of INHalpha mRNA were 0.88 +/- 0.16, 0.61 +/- 0.12, 0.48 +/- 0.15, 0.47 +/- 0.11 and 0.75 +/- 0.19, 0.56 +/- 0.16, 0.53 +/- 0.08, 0.45 +/- 0.10 with significance at all exposure groups (P < 0.01 or P < 0.05). In sertoli cells of rats exposed to 1 000 mg/kg DBP, TEM photos showed more lysosomes in cytoplasm, proliferated and expanded endoplasmic reticulum and nuclei malformation.</p><p><b>CONCLUSIONS</b>Sertoli cell should be one of the major toxic targets. Impairment of spermatogenesis caused by DBP should be partly due to the suppression of ABP and INHalpha biosynthesis.</p>

Effects of mono(2-ethylhexyl) phthalate on testosterone biosynthesis in leydig cells cultured from the rat testis / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effects of mono(2-ethylhexyl) phthalate(MEHP), the primary metabolite of di(2-ethylhexyl) phthalate (DEHP), on testosterone biosynthesis in Leydig cells cultured from the Sprague Dawley rat testis.</p><p><b>METHODS</b>Based on the primary Leydig cell culture model, MEHP exposure groups involved control (0 micromol/L), 62.5, 125, 250, 500 and 1000 micromol/L. We observed mitochondria activity with the MTT method, measured the testosterone level with RIA and determined steroidogenesis acute regulatory protein (StAR) mRNA expression with RT-PCR.</p><p><b>RESULTS</b>After Leydig cells were exposed to MEHP for 24 hours, the activity of mitochondria enhanced evidently at 250 micromol/L and then declined markedly at 1000 micromol/L compared with the control group (P < 0.01). The testosterone level showed an increasing tendency in both basal and hCG-stimulated states with statistical significance at 250 and 500 micromol/L compared with the control group (P < 0.01). However, the expression of StAR mRNA appeared unchanged at 62.5, 125 or 250 micromol/L, but exhibited a decreasing tendency at 500 and 1000 micromol/L (P < 0.01).</p><p><b>CONCLUSION</b>ME- HP directly affected the activity of mitochondria and testosterone biosynthesis of the Leydig cells in vitro. StAR, the regulator of cholesterol transport into mitochondria, might not be responsible for the increase of testosterone biosynthesis induced by MEHP.</p>