Publications by authors named "Kou Tamura"
Article Synopsis
- * The findings revealed a significant decline in multiple pregnancy rates over the 10-year span, with 2021 rates being 3.8% for ovarian stimulation, 2.3% for ovulation induction, and 1.9% for ART compared to higher rates in 2011.
- * Despite the decrease in multiple pregnancies, some adverse neonatal outcomes persisted, showing 40.9% low birth weight and 22.7% neonatal intensive care admissions in 2021, although there were no neonatal deaths reported in
Article Synopsis
- * The study compared levels of OT in the hypothalamus and serum of young versus middle-aged perimenopausal female rats, finding that older rats had higher body weight and fat but similar serum OT levels.
- * The research indicates that while estrogen (E2) helps maintain serum OT levels, other factors influence OT/OT receptor levels, suggesting OT alone may not prevent weight gain or metabolic issues in perimenopausal women.
Article Synopsis
- Previous studies indicate that androgen effects on body weight and appetite vary based on estrogen levels in females, but the exact mechanisms remain unknown.
- The research tested the hypothesis that androgens influence oxytocin levels, an anorectic factor, in ovariectomized female rats with and without estradiol supplementation.
- Findings revealed that testosterone increased oxytocin levels and reduced appetite in estrogen-deficient rats, while having no effect in those with estradiol, suggesting a link between androgens, oxytocin, and appetite regulation influenced by estrogen levels.
Stress responses to bacterial and viral mimetics in polycystic ovary syndrome model rats.
Brain Behav Immun Health
July 2024
Polycystic ovary syndrome (PCOS) is associated with an increased risk of psychological distress as well as enhanced responses to psychosocial stress. Recently, it was hypothesized that PCOS patients may be at high risk of novel COVID-19 infections and worse clinical presentations during such infections. Here, we evaluated the effects of PCOS on stress responses to bacterial and viral mimetics using dihydrotestosterone-induced PCOS model rats.
View Article and Find Full Text PDFActivin A promotes the development of endometriotic lesions in a murine model of endometriosis, and the immunohistochemical localization of phosphorylated suppressor of mothers against decapentaplegic homolog 2/3 (pSMAD2/3) complex in endometriotic lesions has been reported. Activin may therefore be involved in the development and proliferation of endometriotic cells via the SMAD signaling pathway. However, few detailed reports exist on SMAD7 expression in endometriosis.
View Article and Find Full Text PDFArticle Synopsis
- * Ovariectomized female rats were split into control, progesterone-treated, and estrogen-treated groups, with results showing that both hormone-treated groups had lower body weight and fat mass compared to controls.
- * Findings suggest that progesterone may positively influence body weight and appetite regulation, but its mechanisms differ from those of estrogen, particularly regarding hormone levels like oxytocin and leptin in the studied tissues.
Aim: Medroxyprogesterone acetate (MPA) is one of the treatments of atypical endometrial hyperplasia (AEH) and endometrial cancer (EC) to preserve the fertility. Efficacy of MPA therapy and fertility and obstetric outcomes after remission were evaluated in EC or AEH patients.
Methods: Among patients diagnosed with EC or AEH at Tokushima University Hospital between January 2002 and October 2020, we retrospectively analyzed patients, ages range from 26 to 40, who underwent conservative management using MPA (400-600 mg/day).
Article Synopsis
- Recent research shows that excess androgens in women of reproductive age can negatively impact metabolism, appetite, and body weight regulation.
- These androgens increase the risk of metabolic disorders such as obesity and diabetes by affecting appetite regulation and energy expenditure.
- However, these negative effects are not seen in post-menopausal women or ovariectomized animals, suggesting that estrogen levels might play a crucial role in how androgens influence metabolism.
Oxytocin (OT) affects many behavioral, psychological, and physiological functions, including appetite and body weight regulation. Central and peripheral OT levels are markedly affected by gonadal steroids, especially estrogen, and the anorectic effects of estrogen are partially mediated by OT in rodents. In this study, the relationship between the estrogen milieu and serum OT levels was evaluated in women of reproductive age under physiological ( = 9) and supraphysiological estrogenic conditions ( = 7).
View Article and Find Full Text PDFIt has been well established that undernutrition and low energy availability disturb female reproductive functions in humans and many animal species. These reproductive dysfunctions are mainly caused by alterations of some hypothalamic factors, and consequent reduction of gonadotrophin-releasing hormone (GnRH) secretion. Evidence from literature suggests that increased activity of orexigenic factors and decreased activity of anorexigenic/satiety-related factors in undernourished conditions attenuate GnRH secretion in an integrated manner.
View Article and Find Full Text PDFAim: The abnormal secretion of luteinizing hormone (LH) is one of the typical features of polycystic ovary syndrome (PCOS) and adopted in the diagnostic criteria of the Japan Society of Obstetrics and Gynecology (JSOG). We investigated cut-off values for LH and the LH/follicle-stimulating hormone (FSH) ratio in resent two measurement systems for the diagnosis of PCOS.
Methods: Ninety-nine controls and 106 patients with PCOS were enrolled.
Objectives : It has been suggested that the clinical outcomes of frozen-thawed embryo transfer (ET) are superior to those of fresh embryo transfer. We examined whether a freeze-all strategy is necessary for all embryo transfers, and, if not, to evaluate the conditions in which the pregnancy rates of fresh embryo transfer and frozen-thawed ET did not differ. Methods : Patients who underwent blastocyst transfer at Tokushima University Hospital between 2008 and 2019 were enrolled.
View Article and Find Full Text PDFIt has been shown that biotin, a water-soluble vitamin (B7), plays roles in reproductive functions, such as oocyte maturation and embryo development, in experimental animals. On the other hand, little is known about the clinical effects of biotin on human reproduction. In this study, serum and follicular fluid biotin levels were measured in patients who underwent in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), and their associations with reproductive outcomes were evaluated.
View Article and Find Full Text PDFBackground: Although animal models of PCOS have been used in many studies, none of them can reproduce both the reproductive and metabolic phenotypes of PCOS. In addition, behavioral parameters have not been evaluated in PCOS animal models.
Purpose: We tried to produce an improved rat model of PCOS, and the reproductive, metabolic, and behavioral phenotypes of the model rats were evaluated.
Purpose: We studied the influence of psychological stress during the early neonatal period on sexual maturation and sexual behavior in rats.
Methods: Neonatal male and female rats were divided into control (C) and maternal separation (MS) groups (n = 20-24 per group). The pups in the MS groups were placed in isolation cages for 240 minutes/d from postnatal days 2-11.