[Gel centrifugation as a method of separation in radioimmunological determination of serum estrogens].
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Twelve cases of premature ovarian failure (POF) are described. The clinical, hormonal, histopathologic and cytogenetic studies of each patient have been presented. The scope and the limitations of laparoscopic ovarian biopsy are discussed, as is the importance of radioimmunoassay of follicle-stimulating and luteinizing hormones (FSH/LH) in comparison to ovarian biopsy for the diagnosis of premature ovarian failure. A plea is made for the early diagnosis of POF so that these young women can be spared the expensive and time-consuming treatment for the associated problem of infertility.
We have studied a large group of Australian women breastfeeding for an extended period of time to determine the duration of lactational anovulation (n = 89) and amenorrhea (n = 101). Salivary progesterone assays were used to determine ovulation. These women had a mean of 322 days of anovulation and 289 days amenorrhea. Less than 20% had ovulated and less than 25% had menstruated by 6 months postpartum. The latest ovulation was at 750 days and the latest menstruation at 698 days. There was no significant correlation between any measure of maternal nutritional status and the duration of anovulation or amenorrhea. Neither the time of first supplement introduction to the baby nor the amount of supplement given was an accurate predictor of the return of ovulation or menstruation. However, our results clearly show that lactational amenorrhea can provide good protection against pregnancy in the 1st 6 months postpartum, even in well-nourished women who are giving their babies supplemental feeds.
Ceramic drug delivery systems (CDS) are capable of delivering a wide variety of chemicals and/or biologicals directly into the systemic circulation in a continuous manner over long intervals with minimum risk to the recipient. The objectives of the present study were: (i) to determine the capability of tricalcium phosphate (TCP) capsules to deliver estradiol (E) in a sustained manner into the circulation of intact adult male rats, and (ii) to investigate the physiological responses associated with the presence of constant levels of estradiol in adult male rats. Microcrystals, particle size of less than 38 um, of TCP powder were prepared using standard procedures. TCP capsules with an outer diameter of 0.8 cm and an inner diameter of 0.4 cm were prepared by compressing calcined materials in a cylindrical dye at a compression load of 700 Kg. The ceramic capsules had a final density of 1.82 +/- 0.03 gm/cm3. A total of 54 adult male rats were divided into three groups of 18. Each rat in group I was implanted intraperitoneally with 2 CDS, one TCP capsule impregnated with polylactic acid (PLA) and the second nonimpregnated TCP capsule. Each capsule contained 40 mg of E. Animals in group II were implanted with two similar capsules without E (shams) and group III animals which served as intact controls were not fitted with CDS. Eight rats from each group were euthanized 2, 4, or 6 months following CDS implantation. Ceramic capsules were retrieved from the euthanized animals and the amount of E left within the ceramic was determined.(ABSTRACT TRUNCATED AT 250 WORDS)
In this study we have found, that the gingiva epithelium is a sensitive hormonal receptor which may present different histologic and cytologic changes in relation to the hormonal influences acting upon this organ. The oral smears can be used as a reliable test for the evaluation of estrogenic effects in monohormonal conditions.
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Plasma concentrations of LHRH were measured by radioimmunoassay in daily samples obtained from 10 normally ovulating women. The normalcy of each menstrual cycle was determined by measuring luteinizing hormone (LH), follicle-stimulating hormone (FSH), total estrogen, and progesterone concentrations. Six women had consistently measurable immunoreactive LH-releasing hormone (LHRH) in every blood sample. In four, LHRH could not be detected in some of the samples, more frequently during the follicular phase. LHRH levels varied between 10 and 35 pg/ml during the menstrual cycle. At midcycle, coincident with the LH surge, the mean LHRH level (17.6 +/- 4.4 pg/ml) was not significantly different from the mean follicular or luteal phase values. The lowest LHRH level, 11.4 +/- 4.6 pg/ml, was observed on the day of the estrogen surge. A detailed evaluation was made of the specific days of the cycle. Blood samples obtained from an indwelling venous catheter every 20 minutes over a 3 or a 5 hour period during the days of the estrogen surge and the LH surge and on the following day showed no correlation between OHRH, LH, and FSH values.
Estrogen sulfotransferase (EC 2.8.2.4) activity and estrogen receptor levels were measured in 32 human primary breast cancer cytosol preparations. Two types of tumors were identified: type 1, in which estrogen sulfotransferase levels were low (less than 40 pmol 17 beta-estradiol 3-sulfate formed per mg protein per 2 hr) and were independent of [35S]adenosine 3'-phosphate 5'-phosphosulfate production from [35S]sulfate and adenosine triphosphate, and type 2, in which estrogen sulfotransferase levels ranged from 50 to 200 pmol 17 beta-estradiol 3-sulfate per mg protein per 2 hr and were correlated with [35S]adenosine 3'-phosphate 5'-phosphosulfate formation (r = 0.70; p less than 0.005). In type 1 tumors, 11 of 16 were estrogen receptor negative; in type 2 tumors, 2 of 16 were receptor negative. Estrogen sulfotransferase levels in receptor-negative tumors were significantly lower than the levels in receptor-positive tumors (p = 0.025).
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The oestrogen levels were assessed in 180 urine samples taken from 20 cows. The animals had received over 15 days 40 mg one-per-cent oily solution of chloromadinone acetate. The solution had been applied orally or by pour-on methods. The curves of oestrogen excretion were identical for both methods of application, both during and after completed administration. In other words, the effect obtainable from pour-on application is just as good as that obtainable from oral administration.
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Six sexual steroidal hormones (progesterone, pregnenolone, testosterone, ethinyl-oestradiol, oestriol and oestrone) inhibit acetylcholine- and histamine-induced contractions of the isolated guinea-pig ileum. Different degrees of inhibitory capacity were found. High concentrations of PGE1 and F2alpha reverse some of these inhibitions. This reversal seems to be non-specific and probably related to sensitization of the ileal smooth muscle by prostaglandins. The inhibitory action of sexual steroids might be non-specific as well. But a "corticoid-like" effect cannot be excluded.
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