Nicotine exposure impairs germ cell development in human fetal ovaries cultured in vitro.

In the present paper, we found that human fetal ovaries (at ~16 weeks) express the transcripts for several subunits of the nicotinic acetylcholine receptor (nAChR). Exposure to the drug in vitro resulted in the marked increase of apoptosis in the ovaries in a time and dose-dependent manner. Evidence that adverse nicotine effects are potentially due to an increased level of reactive oxygen species (ROS) and consequent DNA damage, both in the ovarian somatic cells and germ cells, are reported. After 4 days of culture, exposure to 1 mM and 10 mM nicotine caused a 50% and 75% decrease, respectively, in the number of oogonia/oocytes present in the fetal ovaries. These results represent the first indication that nicotine may directly cause apoptosis in cells of the fetal human ovary and may lead to a reduction of the ovarian reserve oocytes and consequent precocious menopause in mothers smoking during pregnancy.

Protective effects of melatonin against nicotine-induced disorder of mouse early folliculogenesis.

In this paper, we show that neonatal mice injected for five consecutive days with nicotine display impaired germ cell cyst breakdown and primordial follicle assembly resulting in decreased ovarian reserve lasting until sex maturation age. The effects of nicotine on the pups ovaries were associated with decreased expression of oocyte specific genes such as Nobox, Lhx8, Figlα and Sohlh2. Moreover, the ovaries of pups injected with nicotine showed increased level of cell oxidative stress and autophagic markers (upregulation of AMPKα-1, increased ratio LC3-II/LC3-I, downregulation of AKT and mTOR). Noteworthy, all these effects were counteracted by the administration of the hormone melatonin in 1 µM. In vitro culture of 0 dpp ovaries for 5 days in the presence of 10 µM nicotine reproduced its effect on germ cell cyst breakdown and primordial follicle assembly, furthermore it also revealing about 20% reduction of somatic cells proliferation, and these effects was prevented when melatonin was added to the medium. Taken together these results show that nicotine exposure can adversely affect the establishment of the ovarian reserve in the mouse likely by locally inducing cellular stress altering the primordial follicle assembly and that melatonin, however, is able to counteract such effects.

Clinical effect analysis of microscopic surgery for epiglottis cysts with coblation.

This study aims to explore the effects and advantages of coblation combined with microscopy to treat epiglottis cysts. Ninety patients with epiglottis cysts were randomly assigned to three groups: the first group: marsupialisation + electric coagulation group, n = 30; the second group: marsupialisation + coblation, n = 30; and the third group: marsupialisation + coblation + microsurgery, n = 30. To compare the cure rate, intraoperative bleeding volume, postoperative pain, operation time and postoperative complications were investigated among these three groups. The comparison among three procedures showed a significant difference for intraoperative bleeding volume, operation time and postoperative pain (P < 0.05), whereas no significant difference was observed for cure rate (P > 0.05). These three procedures are effective in treating epiglottis cysts. Microscopic surgery with coblation has the advantages of less bleeding, short procedure duration, less pain and few complications. Thus, microscopic surgery is worthy of clinical application.