stem cells are generally defined as clonogenic cells capable of both self-renewal and differentiation. probably the best method for long-term preservation of spermatogonial stem cells is cryopreservation. in this study, effects of follicle stimulating hormone and testosterone on viability rate of cryopreserved spermatogonial stem cell after thawing were investigated. sertoli and spermatogonial ...

Background: Clomiphene citrate (CC) is still holding its place as the first-line treatment for induction of ovulation in polycystic ovary syndrome (PCOS) patients.  Objective: to assess effect extended clomiphene on pregnancy outcomes resistant PCOS. Patients and methods: this study was conducted 48 PCO patients with CC resistance attended Obstetrics Gynecology Outpatient Clinic at Menoufia U...

background: in vitro maturation (ivm) of oocytes reduces the costs and averts the side-effects of gonadotropin stimulation for in vitro fertilization (ivf). reliable ivm is an intellectual, scientific and clinical challenge with a number of potential applications. objective: the effect of hcg was evaluated on the timing and regulation of in vitro ovulation for the syrian mice oocytes in the pre...

background: follicle stimulating hormone (fsh) plays an essential role in reproductive physiology and follicular development. objective: a new variant of the equine fsh (efsh) gene was cloned, sequenced, and expressed in pichia pastoris (p. pastoris) gs115 yeast expression system. materials and methods: the full-length cdnas of the efshα and efshβ chains were amplified by reverse transcription ...

background: the pattern of islamic fasting differs from other forms of fasting, therefore its effect on health also differs. this research studies the effect of islamic fasting on gonadotropin hormones around the time of the ovulatory cycle and ovulation. materials and methods: this self-controlled study was performed on 24 adult females. blood sampling was performed during ramadan and two mont...

Follicle-stimulating hormone (FSH) secreted by adenohypophyseal cells plays an important role in the regulation of reproduction, but whether microRNAs (miRNAs) regulate the secretion of FSH remains unclear. In the present study, we predicted and screened miRNAs that might act on the follicle-stimulating hormone beta-subunit (FSHb) gene of rats using the TargetScan program and luciferase reporte...

In newts elevated titers of plasma prolactin (PRL), induced by low temperature, cause apoptosis in the penultimatemitotic stage of spermatogonia, and this cell death is suppressed by antiserum against newt PRL, but only during the initial 3 days of exposure (Yazawa et al., 1999). Thus, factors other than PRL must be involved in spermatogonial death. Follicle-stimulating hormone (FSH) may be a p...

To determine the effects of Ramadan fasting on the secretion of sex hormones in single healthy males, we measured blood hormone levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in 52 single male students aged 18-24 years who were fasting for > or = 12 hours during Ramadan. Four blood samples were taken from each, one 2 days before and the others on 10, 20 ...

Specific and sensitive in vitro bioassays suitable for measurement of follicle-stimulating hormone (FSH) in small quantities of serum and urine have recently been validated. Comparisons of bioassay (B-FSH) potencies with immunoassay (I-FSH) estimates and chromatofocusing patterns have facilitated new discoveries regarding the regulation of FSH biosynthesis, storage, secretion, serum concentrati...

OBJECTIVE The aim of the study reported here was to investigate the protective effect of gonadotropin-releasing hormone analog (GnRHa) against cyclophosphamide (CTX)-induced gonadotoxicity. METHODS Eighty Fischer 344 rats were divided randomly into four groups (20 per group). One group received normal saline, one GnRHa, one CTX, and one GnRHa+CTX. Several parameters were used to observe the o...