Résumé
Nano-particles are extensively employed in most industries. Several studies have been started to explore the probable detrimental effects of nano-particles on human reproduction. However, there is insufficient and controversially evident of effects of silver nano-particles on sperm parameters and other reproductive indices. Investigation of the effects of silver nano-particles on sperm parameters, sex hormones and Leydig cells in rat as an experimental model. In this experimental study, 75 male prepubertal Wistar rats were categorized in five groups including control group and 4 experimental groups [n=15 in each group]. The rats in the experimental groups were fed silver nano-particles [60 nm in dimension] with concentrations of 25, 50, 100, and 200 mg/kg/day. After 45 days [about one duration of spermatogenesis in rat], samples of blood were taken from the rats for testosterone, leuteinizing hormone [LH], and follicle stimulating hormone [FSH] assessments. Afterwards, the epididymis and the testis of each rat were dissected for analyzing sperm parameters and Leydig cells. The results demonstrated a statistically significant reduction in number of Leydig cells in experimental groups compared to control one. In addition, the data showed a reduction in testosterone and a rise in LH level which was more obvious in high doses [p<0.05]; however, FSH level showed a reduction but it was not statistically significant. A significant decrease was also found in sperm motility and normal sperm morphology in the experimental groups compared to the control one. Our results demonstrated that silver nano-particles, in addition to interruption in functions of sex hormones, can diminish the number of Leydig cells and sperm parameter indices. It should be noted that the effects of nano-particles on reproductive indices are dose-dependent
Résumé
There is no general agreement as to which treatment is best for hyperthyroidism. The objective of this study is to investigate the effectiveness of continuous methimazole [MMI] treatment and to compare the results of neuropsychological testing in patients receiving long-term continuous MMI to those on replacement thyroxine following radioiodine-induced [RAI] hypothyroidism. We enrolled 239 patients with diffuse toxic goiter who had recurrences of hyperthyroidism. Of these, 104 patients were randomized into two groups, MMI and treatment with thyroxine following RAI hypothyroidism. The remaining 135 patients voluntarily enrolled into either of the two groups. From all patients, 59 MMI-treated patients and 73 patients in the RAI group completed follow up. Thyroid function tests, serum lipids and lipoproteins, echocardiography, bone mineral density [BMD] and seven neuropsychology tests were performed at the final visit. In the RAI group compared to the MMI-treated group during a mean of 14 years follow up, there were more incidences of elevated TSH [> 5 mU/L; adjusted relative risk [RR] 1.23; 95% confidence interval [CI] 1.04-1.47], increased triglycerides [> 150 mg/dL; RR 2.20; 95% CI 1.34-3.62], HDL-C [< 40 mg/dL; RR 3.46; 95% CI 1.40 - 8.53], and early diastolic annular velocity [< 12.2 cm; RR 3.91; 95% CI 1.42-10.74], in addition to a decreased early diastolic to annular velocity ratio [< 6.7; RR 7.14; 95% CI 1.38-34.48]. The MMI group scored better in neuropsychology tests that included mood, direction, logical memory, repeated numbers, and intelligence quotient [IQ]. Long-term MMI treatment was superior to RAI therapy in patients with diffuse toxic goiter when mood, cognition, cardiac function and occurrence of thyroid dysfunction were compared