Kazuhiro Shirasu

Effect of Estriol on Bone Loss in Postmenopausal Japanese Women: A Multicenter Prospective Open Study

Objectives: To assess the effects of oral estriol on the bone mineral density (BMD) and bone metabolism in postmenopausal women.

Mechanisms involved in the pituitary desensitization induced by gonadotropin-releasing hormone agonists

OBJECTIVE We investigated the mechanisms of desensitization induced by gonadotropin-releasing hormone agonist in the pituitary. STUDY DESIGN Effects of gonadotropin-releasing hormone agonist on the pituitary were studied in vitro and in vivo in the rat. In the clinical study serum luteinizing hormone was measured by radioimmunoassay with a polyclonal luteinizing hormone antibody (luteinizing hormone-radioimmunoassay) and by immunoradiometric assay with monoclonal luteinizing hormone antibodies (luteinizing hormone-immunoradiometric assay) during gonadotropin-releasing hormone agonist treatment. RESULTS In the in vitro study bead-attached pituitary cells that were desensitized with a continuous infusion of 10(-7)mol/L gonadotropin-releasing hormone responded to 50 mmol/L K+. In the in vivo study gonadotropin-releasing hormone binding sites and rat luteinizing hormone beta-messenger ribonucleic acid in the pituitary decreased during gonadotropin-releasing hormone agonist treatment, but serum levels of rat luteinizing hormone did not decrease. In addition, a disparity between luteinizing hormone-radioimmunoassay and luteinizing hormone-immunoradiometric assay was demonstrated during gonadotropin-releasing hormone agonist treatment. CONCLUSION Pituitary desensitization in response to gonadotropin-releasing hormone agonist may not be wholly receptor mediated and a nonreceptor process may be involved.

Guidelines for office gynecology in Japan: Japan Society of Obstetrics and Gynecology and Japan Association of Obstetricians and Gynecologists 2011 edition

Gynecology in the office setting is developing worldwide. Clinical guidelines for office gynecology were first published by the Japan Society of Obstetrics and Gynecology and the Japan Association of Obstetricians and Gynecologists in 2011. These guidelines include a total of 72 clinical questions covering four areas (Infectious disease, Malignancies and benign tumors, Endocrinology and infertility, and Healthcare for women). These clinical questions were followed by several answers, backgrounds, explanations and references covering common problems and questions encountered in office gynecology. Each answer with a recommendation level of A, B or C has been prepared based principally on evidence or consensus among Japanese gynecologists.These guidelines would promote a better understanding of the current standard care practices for gynecologic outpatients in Japan.

Low-dose GnRH agonist therapy for the management of endometriosis.

Objective: In order to examine whether treatment with a GnRH agonist alone can maintain estrogen levels within the “estrogen window” that inhibits endometriosis without influencing bone‐mineral density, we studied the effects of GnRH agonist therapy and changes in bone‐mineral density.

Huge ovarian endometrial cyst: a case report

We are reporting a rare case of a huge ovarian endometrioma, one as large as an adult head, and the difficulty of differential diagnosis regarding this ovarian tumor.