Search results for "Gonad"
showing 10 items of 240 documents
Data from: Testis asymmetry in birds: the influences of sexual and natural selection
2014
Gonad size and shape asymmetries are particularly common in birds. Although some obvious size and shape differences between the left and right testes in birds were first documented more than a century ago, little is known about what influences the variation across species in either the degree or the direction of these asymmetries. Here we show that a left bias in size is the most likely ancestral state in most orders and families, and that there is a weak but significant negative relation between the degree of size and shape asymmetries. In extant species, testis size and shape symmetries increase with the degree of sperm competition (relative testes mass), but those relations are significa…
Differential effects of sex hormones on peri- and endocortical bone surfaces in pubertal girls.
2005
Context: The role of sex steroids in bone growth in pubertal girls is not yet clear. Bone biomarkers are indicators of bone metabolic activity, but their value in predicting bone quality has not been studied in growing girls. Objective: This study examines the association of sex hormones and bone markers with bone geometry and density in pubertal girls. Design: The study was designed as a 2-yr longitudinal study in pubertal girls. Measurements were performed at baseline and at 1and 2-yr follow-ups. Setting: The study was conducted in a university laboratory. Participants: A total of 258 10- to 13-yr-old healthy girls at the baseline participated. Methods:Peripheralquantitativecomputedtomogr…
Relationship of sex hormones to bone geometric properties and mineral density in early pubertal girls.
2004
This study aimed to evaluate the associations among serum 17beta-estradiol (E2), testosterone (T), sex hormone-binding globulin (SHBG), bone geometric properties, and mineral density in 248 healthy girls between the ages of 10 and 13 yr old. The left tibial shaft was measured by peripheral quantitative computed tomography (Stratec XCT-2000; Stratec Medizintechnik, GmbH, Pforzheim, Germany). The cortical bone and marrow cavity areas were expressed as proportions of the total tibial cross-sectional area (CSA). Cortical thickness and total volumetric bone mineral density (vBMD) were also determined. These tibial geometric and densitometric measures were correlated against the serum sex hormone…
Anti-androgens for the treatment of hirsutism.
2002
Many alternatives exist for treating hirsutism. Based on an analysis of scientific literature and on the experiences of the author, the most common anti-androgen agents are discussed in this review. Androgen receptor blockers (cyproterone acetate, flutamide and spironolactone), 5 alpha-reductase inhibitors (finasteride) and androgen-suppressing agents (gonadotrophin-releasing hormone [GnRH] agonists, oestroprogestins, corticosteroids and insulin-sensitising agents) are evaluated and compared. The importance of diagnosis in choosing the most appropriate anti-androgen treatment is also discussed.
Body composition and muscle performance during menopause and hormone replacement therapy.
2003
Menopausal transition is characterized by ovarian failure and its consequent decrease in female sex steroid production. Earlier studies suggest that an increase and redistribution of body fat during menopause predispose women to cardiovascular disease and metabolic syndrome. In addition, peri- and post-menopausal women seem to have less lean body mass (LBM) compared with pre-menopausal women. Accordingly, a changing ovarian hormonal status may accelerate the loss of muscle mass and result in decreased muscle performance and functional capacity. Hormone replacement therapy (HRT) has been used to treat menopausal symptoms and as a primary prevention therapy in chronic conditions. Inconsistent…
Authors’ Response: Relationship of Sex Hormones to Bone Geometric Properties and Mineral Density in Early Pubertal Girls: Use of Correlation Analyses
2004
Association of female aging with decreased parthenogenetic activation, raised MPF, and MAPKs activities and reduced levels of glutathione S-transfera…
2004
This study aims to determine in the mouse whether oocytes from reproductively old females exhibit a different susceptibility to be parthenogenetically activated when compared to oocytes from young females. At the age of 10–12 (young-female group) or 60–62 (old-female group) weeks, hybrid female mice were superovulated using pregnant mare's serum gonadotropin (PMSG) followed by human chorionic gonadotropin (hCG) 48 hr later. After removing the cumulus cells, oocytes were exposed to any of two different activating protocols: (a) 6-min exposure to 8% ethanol; and (b) treatment with 200 μM thimerosal for 15 min followed by 8 mM dithiothreitol (DTT) for 30 min. Oocytes from old female mice displ…
Goserelin acetate to avoid hysterectomy in pre-menopausal women with fibroids requiring surgery
1999
Objective: To obtain information on the efficacy of repeated short cycles of GNRH agonist treatment in order to avoid hysterectomy in near-menopausal women with symptomatic fibroids. Study design: 72 pre-menopausal women (mean age 50 years) with one or more uterine fibroids >10 cm in diameter, symptomatic menorrhagia lasting three months or more and haemoglobin=9 g/dl entered the study. The patients were randomized with ratio of approximately 1:4 to: (a) immediate surgery; or (b) treatment with goserelin acetate. Patients randomized to goserelin acetate received a first cycle of 3.6 mg depot once every 28 days for four months. They were followed-up for three years. If menorrhagia was observ…
Endocrinology and physiology of pseudocyesis
2013
This literature review on pseudocyesis or false pregnancy aims to find epidemiological, psychiatric/psychologic, gynecological and endocrine traits associated with this condition in order to propose neuroendocrine/endocrine mechanisms leading to the emergence of pseudocyetic traits. Ten women from 5 selected studies were analyzed after applying stringent criteria to discriminate between cases of true pseudocyesis (pseudocyesis vera) versus delusional, simulated or erroneous pseudocyesis. The analysis of the reviewed studies evidenced that pseudocyesis shares many endocrine traits with both polycystic ovarian syndrome and major depressive disorder, although the endocrine traits are more akin…