Biomedical subjects

A J Duleba

Publications and source records attributed to A J Duleba.

39 records · Page 3Linked to original sources

PubMed1982

Comparative studies of androgen metabolism in theca and granulosa cells of human follicles in vitro.

In eight separate experiments, theca and granulosa were isolated from human follicles (5-25 mm in diameter), and their capacities to metabolize radiolabelled testosterone in 24 hour cultures were assessed. Theca metabolized testosterone primarily to androstenedione, however significant aromatization to estradiol-17 beta and to estrone was also observed. Granulosa metabolized testosterone primarily to estra-diol-17 beta and estrone, while smaller quantities were converted to androstenedione. In seven of these experiments, the intermediate of aromatization, 19-hydroxytestosterone, was identified. In six of these experiments, theca, when compared to granulosa, produced more androstenedione but less estradiol-17 beta and estrone. 5 alpha-Reduced androgens were non-detectable or produced in small quantities. In a single experiment, metabolism of androstenedione was compared to metabolism of testosterone by both theca and granulosa. Theca metabolized androstenedione to testosterone in smaller quantities than testosterone to androstenedione. Granulosa metabolized androstenedione to testosterone in higher quantities than testosterone to androstenedione. Both theca and granulosa aromatized androstenedione more readily than testosterone.

Adult↗

PubMedDate not supplied

Androgens and therapeutic aspects of antiandrogens in women.

OBJECTIVES: We reviewed the mechanisms of androgen actions and the established and experimental uses of antiandrogens in women. METHODS: Relevant studies were identified through a computerized bibliographic search (MEDLINE) and through manual review of bibliographies in relevant publications. RESULTS: Androgens exert major effects on the functions of gonads, sex organs, and various "nonreproductive" organs and systems, including muscles, liver, skin, nervous system, and the immune system. Most, but not all, of the actions of androgens may be explained by their binding with specific androgen receptors. Antiandrogens prevent androgens from expressing their activity at target cells. They act primarily by binding to androgen receptors and thus preventing activation of receptors by androgens. Steroidal antiandrogens may also exert a wide range of other hormonal and antihormonal effects by interacting with receptors for progesterone, glucocorticoids, and mineralocorticoids. Furthermore, some antiandrogens may decrease the production of androgens by acting at the hypothalamic-pituitary unit and modifying the release of LH, or by directly inhibiting individual enzymes involved in steroidogenesis. Antiandrogens are widely used in the treatment of women with various hyperandrogenic conditions, including polycystic ovary syndrome, idiopathic hirsutism, acne, seborrhea, and hair loss. CONCLUSIONS: Antiandrogens provide a logical and clinically effective pharmacotherapy of hyperandrogenic disorders. However, both steroidal and nonsteroidal antiandrogens may cause significant side effects, largely because of their interactions not only with androgen receptors, but also with other receptors and various enzymatic activities. Difficulties in designing the optimal antiandrogen largely result from the complexities of androgen metabolism and action in various tissues.

Androgen Antagonists↗

PubMedDate not supplied

Intracervical placement of catheter balloon at hysterosalpingography.

OBJECTIVE -- To describe the technique of hysterosalpingography with endocervical placement of the balloon of the catheter rather than endometrial placement. PATIENTS -- 48 consecutive patients undergoing hysterosalpingography in the course of infertility work-up at a university hospital. METHOD -- With the patient in the lithotomy position, the cervix is visualized and cleansed. The catheter and balloon are inserted in the cervical canal and inflated with the contrast agent. The contrast agent is injected slowly at low pressure, and three to six spot films are obtained. Only gentle traction can be applied by this method, so oblique views are obtained early in the examination. RESULTS -- Balloon placement was atraumatic. Although good views were obtained more frequently than with traditional techniques, about one-quarter of the studies were unsatisfactory. CONCLUSION -- This method is easy, atraumatic, and allows excellent visualization of the entire endometrial cavity and upper intracervical canal.

Catheterization↗