Although experimental and clinical evidence suggest that endogenous sex hormones influence bone sarcoma genesis, the hypothesis has not been adequately tested in an appropriate animal model. We conducted a historical cohort study of Rottweiler dogs because they frequently undergo elective gonadectomy and spontaneously develop appendicular bone sarcomas, which mimic the biological behavior of th...

Effective contraception is necessary in countries where limiting population growth has become a public policy imperative. The main antigenic targets for contraceptive vaccine development can be listed as following: 1) sperm antigens, 2) zona pellucida antigens, 3) gonadotrophin-releasing hormone, 4) chorionic gonadotrophin, 5) other protein/peptide hormones (follicle-stimulating hormone, lutein...

Steroid hormones have a large number of functions in the organism, including the regulation of stress response, the electrolytic balance, and reproduction. The synthesis of these hormones is mediated by a series of enzymes, which produce glucocorticoids, mineralocorticoids, progestins, androgens and estrogens using cholesterol as the metabolic main precursor. In this general way, steroid synthe...

OBJECTIVE Onset of schizophrenia occurs during the reproductive period in more than 80% of those affected. The author reviews neuroendocrine and physiologic events that occur in the basal forebrain at the initiation of and throughout the reproductive period and proposes their possible relationship to the onset of schizophrenia. METHOD The neuroendocrine changes that occur in specific areas of...