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A Segaloff

Publications and source records attributed to A Segaloff.

At least 19 recordsLinked to original sources

Structure of 3-hydroxy-1-methyl-1,3,5(10)-estratriene-11,17-dione.

C19H22O3, Mr = 298.39, orthorhombic, P2(1)2(1)2(1), a = 11.332 (6), b = 14.596 (7), c = 9.567 (4) A, V = 1582.6 (5) A3, Z = 4, D chi = 1.252 Mg m-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.0778 mm-1, F(000) = 640, T = 273 K, R = 0.067 for 1762 unique observed reflections where F greater than 2 sigma (F). The structure was studied to observe the effect of 1-methyl and 11-keto substitution. The 3-hydroxyl is hydrogen bonded to O11 at 2.76 A. The B ring is in a 7 alpha, 8 beta half-chair conformation. The molecule twists about the C(9)--C(10) bond to relieve the steric interaction between the 1-methyl and 11-keto groups. The C1--C10--C9--C11 torsion angle is 55 vs 33.5 degrees, the average of 38 estradiol analogue structures.

Estrone

The in vivo metabolism of 7 beta, 17-dimethyltestosterone-6,7-3H.

7 beta, 17-Dimethyltestosterone (17 beta-hydroxy-7 beta, 17-dimethyl-4-androsten-3-one) (I) was given to three subjects in oral doses of 400 mg per day for ten days. The initial dose contained the steroid tritiated in the 6 and 7 positions. Plasma levels and urinary excretion patterns were followed in all three subjects. Isolations were done on the urine, plasma, and stools of one patient. From the urine 7 beta, 17-dimethyl- 5 alpha-androstane-3 beta,17 beta-diol (VI) was isolated from the nonhydrolyzed fractions. Unchanged (I), 7 beta,17-dimethyl-5 beta-androstane-3 alpha,17 beta-diol (III) and 7 beta, 17-dimethyl-5 beta-androstane-3 beta,17 beta-diol (IV) were isolated from the nonhydrolyzed and enzyme-hydrolyzed fractions. 7 beta,17-dimethyl-5 alpha-androstane-3 alpha,17 beta-diol (V) was isolated from the enzymatic fractions. From the stools were isolated unchanged (I), (III), (IV), (V), and (VI). Unchanged (I) and its 5 alpha-dihydro derivative (17 beta-hydroxy-7 beta,17-dimethyl-5 alpha-androstan-3-one) (II) were identified in the plasma. The total recovery of radioactivity in the one patient on whom the isolations were done was 57%; 40% from the urine and 17% from the stools.

Adult

The pros and cons of estrogen therapy.

Hormone deficiency is the most obvious indication for its use, but estrogen therapy is sometimes beneficial in other conditions. Since rather serious complications are now being associated with such therapy, however, a decision to use estrogen calls for caution in determining the dose and the duration of administration.

Adenoma

Relaxin.

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Amino Acid Sequence

Plasma immunoreactive relaxin levels in pregnant and nonpregnant women.

Immunoreactive relaxin was measured in plasma samples obtained from human volunteers utilizing the RIA procedure of Sherwood et al., as modified by O'Byrne and Steinetz for heterologous plasma samples. Immunoreactive hormone was not detected in samples obtained from men, and only rarely in plasma of nonpregnant women. Immunoreactive relaxin was present as early as the fourth week of pregnancy and was detectable throughout the course of gestation. Immunoreactive relaxin tended to be higher early in pregnancy, and there was no peak just before parturition as occurs in many other species. Our results are at variance with those of Bryant and coworkers, who reported high levels of immunoreactive relaxin in men and nonpregnant as well as pregnant women. The possible reasons for this discrepancy are presented.

Contraceptives, Oral, Combined

Current status of estrogen and progesterone receptors in breast cancer.

Breast cancer is often hormone responsive, since growth or regression of tumors can often be modulated by appropriate endocrine manipulations. Estrogen and progesterone appear to be major hormones involved in regulation of breast tumor growth. It has been recently argued that a more accurate marker of hormonal responsiveness might result if an end product of an intact estrogen response system were measured instead of the initial hormone binding step. Progesterone receptor (PgR) has been investigated in this regard since it can be readily measured in human breast tumors and there is clear evidence in experimental breast tumor model systems that PgR is under acute estrogen control. PgR is rarely found in ER- metastatic breast tumors but is present in approximately 59% of ER+ metastatic tumors, especially in those tumors with high levels of ER. Preliminary clinical correlation of ER, PgR and response to endocrine therapy is encouraging. The response rate is significantly higher if the tumor contains both ER and PgR than if the tumor contains ER alone.

Adrenalectomy

Appraising current therapy for breast cancer. 3. Hormonal manipulation and chemotherapy.

Hormonal manipulation and chemotherapy used as adjuvants to surgery are aimed at controlling systemic micro-metastases from breast cancer. Primary hormonal manipulation consists of oophorectomy (for premenopausal women) or hormone administration. Hormone receptors, which are sometimes present in tumors, are now being measured and tested for their predictive value as to which tumors will respond to manipulation. Systemic chemotherapy has been used for years, but no drug that is specific against mammary tumors has yet been discovered. New drugs or combinations of older drugs are constantly being tested. To acquire a good data base for future decisions, systemic chemotherapy should be administered and patients followed up according to carefully constructed protocols.

Breast Neoplasms

Hormone treatment of breast cancer.

Alteration of the hormonal milieu is still one of the major and most successful methods for treating advanced breast cancer. With the exception of the use of thyroid hormone in conjunction with corticosteroids, we are not aware of any proved advantageous combination of hormonal agents that improves the objective regression rates in advanced breast cancer.

Adrenal Cortex Hormones

Combined androgen and antimetabolite therapy of advanced female breast cancer. A report of the cooperative breast cancer group.

A clinical trial of androgen and antimetabolite therapy of advanced female breast cancer was conducted in 110 patients by the Cooperative Breast Cancer Group. An objective regression rate of 20% was achieved in women receiving oral testolactone, 6% in patients given intravenous fluorouracil alone, and 14% when the androgen and antimetabolite were administered together. This randomized trial according to the CBCG protocol did not produce the high regression rate noted previously in a nonrandomized, nonprotocol evaluation of these drugs.

Administration, Oral

Spontaneous adenocarcinomas of the ventral prostate of aged A X C rats.

Spontaneous adenocarcinomas of the ventral prostate were present in 7 of 41 aged (34- to 37-month-old), virgin, untreated male A X C rats. The only consistent gross evidence of possible neoplastic involvement was intraprostate hemorrhage. The principally intraglandular neoplasms were composed of markedly anaplastic epithelial cells which retained a moderate propensity to form glandular patterns. The nuclei of the neoplastic cells were pleomorphic, vesiculated, enlarged, and hyperchromatic. Mitotic figures were frequent. Interglandular connective tissue was invaded in one rat; however, metastases were not demonstrated.

Adenocarcinoma