We have studied the modulation and differential sensitivity of the estrogen receptor (ER) in breast cancer in the presence of protecting or modifying agents of disulfide bonds and sulfhydryl groups present in the ER steroid-binding domain. Protecting agents such as mercaptoethanol and dithiotreitol increased the [(3)H]estradiol binding to ER by 25% and 50%, respectively. Modifying agents such as p-chloromercuribenzensulfonate decreased the [(3)H]estradiol binding by 70% and this was nearly completely abolished by N-ethylmaleimide (94%).
View Article and Find Full Text PDFThe objective of this comparative study was to determine the influence of changes in estradiol and progesterone during ovulatory vs. anovulatory cycles on levels of estradiol receptor (ER) and progesterone receptor (PgR) in endometrium. Thirty women (range age 20-35 years) were divided into three groups: women with a history of habitual abortion, obese women with menstrual disorders, and women with regular ovulatory cycles as well as proven fertility.
View Article and Find Full Text PDFBy centrifugation in a sucrose density gradient we studied the citosol 17beta-estradiol binding sites of blastocyst receptive and non-receptive endometrial zones, as well as uterine horn endometrium whose ovary was extirpated three weeks before pregnancy. The cytosol was prelabelled with [3H]-17beta-estradiol 2 and 25 nM. In this work two incubation temperatures were studied.
View Article and Find Full Text PDFGynecol Endocrinol
December 2005
The effect of administration time of tamoxifen was assessed in 52 postmenopausal patients with mammary cancer in order to evaluate its effect on endometrium and serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol. Mean age of the patients was 61.5 years, 23% had a history of smoking, mean body mass index (BMI) was 26.
View Article and Find Full Text PDFObjective: To study the influence of oral contraception use as risk factor for human papillomavirus infection (HPV) and progression to cervical intraepithelial neoplasia (CIN).
Materials And Methods: A prospective, transversal and comparative study of 84 female patients in reproductive age that had used oral contraception for more than three years as birth control method and who had CIN mild (CIN I), moderate (CIN II) or severe (CIN III) associated or not to HPV infection documented by colposcopy, pathology and cytology was done. 84 cases and 60 controls submitted to a directed interrogation were studied.