Akihisa Takasaki

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We investigated the relationship between oxidative stress and poor oocyte quality and whether the antioxidant melatonin improves oocyte quality. Follicular fluid was sampled at oocyte retrieval during in vitro fertilization and embryo transfer (IVF-ET). Intrafollicular concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in women with high rates of(More)
This review summarizes new findings related to beneficial effects of melatonin (N-acetyl-5-methoxytryptamine) on reproductive physiology. Recently many researchers have begun to study the local role of melatonin as an antioxidant. We focused on intra-follicular role of melatonin in the ovary. Melatonin, secreted by the pineal gland, is taken up into the(More)
Melatonin (N-acetyl-5-methoxytryptamine) is secreted during the dark hours at night by pineal gland, and it regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It has been believed that melatonin regulates ovarian function by the regulation of gonadotropin release in the hypothalamus-pituitary gland(More)
Melatonin (N-acetyl-5-methoxytryptamine) is secreted during the dark hours at night by the pineal gland. After entering the circulation, melatonin acts as an endocrine factor and a chemical messenger of light and darkness. It regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It also affects the(More)
BACKGROUND Additional treatment with a gonadotropin-releasing hormone (GnRH) agonist (GnRHa) before IVF-ET (ultralong GnRHa therapy) has been reported to improve the outcome of IVF-ET in endometriosis patients. However, the mechanism of ultralong GnRHa therapy is unclear. It is suggested that inflammatory cytokines and oxidative stress contribute to(More)
OBJECTIVE To investigate the relationship between growth hormone (GH) and luteal function. DESIGN In vivo comparative and in vitro culture studies. SETTING University hospital. PATIENT(S) Eighteen women who were interested in becoming pregnant and visited our clinic voluntarily participated in the study for urinary GH measurement. Ten women undergoing(More)
OBJECTIVE To examine changes in blood flow in the corpus luteum throughout the luteal phase and during early pregnancy. DESIGN Longitudinal and cross-sectional prospective studies. SETTING University hospital and city general hospital. PATIENT(S) Sixty-one women with normal menstrual cycles and normal luteal function, 13 women with hCG-induced(More)
OBJECTIVE To characterize pathophysiologic features of a "thin" endometrium. DESIGN A prospective observational study. SETTING University Hospital and City General Hospital. PATIENT(S) Patients with normal-thickness endometrium (Normal-Em group: endometrial thickness >or=8 mm; n = 57) and thin endometrium (Thin-Em group: endometrial thickness <8 mm; n(More)
OBJECTIVE To examine whether thin endometria can be improved by increasing uterine radial artery (uRA) blood flow. DESIGN A prospective observational study. SETTING University hospital and city general hospital. PATIENT(S) Sixty-one patients with a thin endometrium (endometrial thickness [EM] <8 mm) and high radial artery-resistance index of uRA(More)
This study investigated whether melatonin protects luteinized granulosa cells from reactive oxygen species (ROS) as an antioxidant to enhance progesterone production in the follicle during ovulation. Follicular fluid was sampled at the time of oocyte retrieval in women undergoing in vitro fertilization and embryo transfer (IVF-ET). Melatonin concentrations(More)