Sub 23 µHz instantaneous linewidth and frequency stability measurements of the beat note from an offset phase locked single frequency heterodyned Nd:YAG laser system.

We report, what is to the best of our knowledge, the narrowest instantaneous linewidth measurement of the beat frequency between two phase locked heterodyned 1.319 µm Nd:YAG lasers. At both 65 kHz and 31.7 GHz beat frequencies, we measured the instantaneous 3 dB linewidth of the optically-generated microwave tones to be < 22.8 µHz, limited only by the minimum instrument resolution. Allan deviation measurements indicate that the laser system follows a 5 MHz quartz reference oscillator to stability levels of σy (1s) = 8.4 × 10-12. At 10.24 GHz, the laser system follows a sapphire loaded cavity oscillator to stability levels of σy (1s) = 1.6 × 10-11. For these measurements, the optical beat note closely follows the linewidth and stability of the driving microwave frequency reference.

Suppression of prolactin secretion in normal young women by 2-hydroxyestrone.

The nonuterotropic natural estrogen 2-hydroxyestrone administered to normal young women results in a prompt and profound suppression of serum prolactin in most of the subjects. With the exception of dopamine, this is the only endogenous material known to strongly inhibit prolactin secretion, and its action suggests that the physiological regulation of prolactin by estrogens in the human is dual in nature, consisting of stimulation by estradiol and inhibition by its catechol estrogen metabolite.

The plasma estradiol as an index of fetoplacental function.

A radioligand assay has been developed for the measurement of unconjugated 17beta-estradiol in as little as 0.01 ml of pregnancy plasma employing rabbit uterine cytosol as specific binder and activated charcoal as nonspecific absorbant. Large numbers of samples could be processed simultaneously at relatively little expense and results were obtainable within 3 hr. The procedure was sensitive to 1 ng/ml. No diurnal or positional variations were found. Values from 250 unselected normal patients showed a constantly rising mean plasma E(2) from 18 to 35 wk gestation from 4.5 to 14 ng/ml. From 35 to 40 wk, mean E(2) rose only to 15 ng/ml and the range of values increased substantially. When 22 normal pregnant subjects were followed serially, rising levels of plasma E(2) were found with no significant fall ever seen. By contrast, patients exhibiting fetal distress generally had falling or reduced E(2) levels. However, 3 cases of Rh isoimmunization had elevated or normal E(2) concentrations even after clearcut evidence of fetal demise. A decrease of 45% in E(2) concentration was associated with intraamniotic instillation of hypertonic saline prior to delivery supporting the view that placental conversion of maternal adrenal precursors is responsible for about half of the E(2) production in pregnancy. The postpartum clearance of endogenous E(2) was measured and found to fit a two compartment model with mean half-time of 22 min and 7 hr. Follicular phase levels of E(2) were attained by 35 hr postpartum. The concentration of unconjugated E(2) in pregnancy plasma correlated as well with the state of the placenta as other placental hormone measurements and holds promise of being a rapid, inexpensive, and reliable method of following patients with high-risk pregnancies in a variety of clinical settings.

Cytoplasmic and nuclear progestin receptors in human myometrium during the menstrual cycle and in pregnancy at term.

Exchange assays have been developed for the determination of the total progestin in receptor sites (unoccupied and occupied with endogenous hormone) in the cytosol and nuclei of human myometrium using radiolabeled R5020 (17,21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione) as ligand. These assays have been applied to the measurement of cytosol and nuclear progestin receptor sites in the myometrium during the menstrual cycle and in pregnancy at term. Both the cytosol receptor levels as well as the sum of cytosol and nuclear receptor levels were highest during the proliferative phase of the cycle, dropped moderately but significantly in the secretory phase, and decreased markedly in pregnancy at term. Despite the marked drop in cytosol receptor levels, nuclear receptor levels in pregnancy at term were similar to those observed in the proliferative or secretory phase. In addition, the fraction of the total cellular receptor that was associated with the nucleus increased from 5.5% in the proliferative phase to 60% in pregnancy at term. The decrease in cytosol progestin receptor concentration as well as the relative increase in nuclear localization of the receptor in human myometrium in pregnancy at term may be related to the high circulating progesterone levels.

The use of constant infusion of unlabeled dehydroepiandrosterone for the assessment of its metabolic clearance rate, its half-life, and its conversion into estrogens.

We have exploited the feasibility of utilizing constant infusion of unlabeled dehydroepiandrosterone (DHEA) for calculating its MCR, its half-life (t1/2), and its conversion ratio into estrogens. In nonpregnant women, results obtained by infusion of unlabeled DHEA were similar to those obtained by the infusion of either labeled steroid or a mixture of labeled and unlabeled steroid. An increase of 3-fold in the infusion rate did not change any of these results, indicating that enzyme availability was not a limiting step in the production of estradiol (E2) from DHEA. When compared to the nonpregnancy state, term pregnancy was not associated with a change in plasma DHEA concentrations, but the MCR of DHEA of 76.8 +/- 18.8 (SE) liters/kg.day was 2.5-fold higher and the t1/2 of 22.5 +/- 3.6 min was 2-fold lower. The conversion ratio of DHEA into E2 increased during pregnancy by 500-fold, and DHEA contributed 9% of maternal circulating E2. In the first postpartum day, the MCR of DHEA and its t1/2 were not significantly different from those of term pregnancy, suggesting that the increased MCR of DHEA in pregnancy was not solely due to increased clearance of DHEA by the placenta.

Variations in estrone sulfatase activity in human leukocytes.

Peripheral blood leukocytes isolated from men and women were studied for their capacity to metabolize estrone (E1) sulfate. Fresh human leukocytes (granulocytes and mononuclear cells) were incubated in phosphate buffer, pH 7.4, containing [3H]E1S for 1 h at 37 C. The samples were extracted with chloroform for measurement of the [3H]E1 formed, and the results were corrected for nonenzymatic hydrolysis. The mean E1 sulfatase activity in leukocytes isolated from normal women in the follicular phase of their cycle was 75% higher than that during the luteal [1840 +/- 179 (+/- SE) vs. 1048 +/- 101 fmol E1 micrograms protein-1 h-1; P less than 0.004] and higher than that in normal men (875 +/- 123; P less than 0.002), but was not different from that in menopausal (1349 +/- 151) or hirsute women (1700 +/- 222). In pregnant women, the mean leukocyte E1 sulfatase activity was significantly lower (861 +/- 147) than that in nonpregnant women in the follicular phase (P less than 0.003). These results suggest that progesterone may modulate E1 sulfatase activity, whereas estrogens do not.

Human fatty marrow aromatizes androgen to estrogen.

Human female fatty marrow from the femur and iliac crest has the ability to convert androgen to estrogen. Homogenates of fatty marrow incubated with 19-[6,7-3H]hydroxyandrostenedione (19-hydroxyandrost-4-ene-3,17-dione) and an NADPH-generating system produced estrogen in all six samples. The major estrogen produced in five of the cases was [3H]estrone, the immediate product of the aromatizaton of 19-hydroxyandrostenedione. One case produced [3H]estradiol. The local formation of estrogens in bone marrow may be important to the closure of the epiphyses at puberty and may affect osteoporosis at the menopause.

Effects of dexamethasone on fetal and maternal thyroxine, triiodothyronine, reverse triiodothyronine, and thyrotropin levels.

The concentrations of T4, T3, rT3, and TSH were measured at term pregnancy in maternal and umbilical plasma and in amniotic fluid of 11 normal patients who received 8-16 mg dexamethasone 3-48 h before elective cesarean section and of 10 control patients who received no dexamethasone. The mean (+/- SE) concentrations of T4 (micrograms per dl) in maternal and umbilical plasma of dexamethasone-treated patients (12.5 +/- 0.9 and 13.0 +/- 0.9) were not significantly different (P less than 0.05) from those of the control patients (13.9 +/- 1.5 and 10.4 +/- 0.6, respectively). The mean (+/- SE) maternal plasma concentrations of T3 and rT3 (nanograms per dl) of dexamethasone-treated patients (204 +/- 6 and 82 +/- 11) were not significantly different (P less than 0.05) from those of the control patients (201 +/- 26 and 72 +/- 6, respectively). However, the mean (+/- SE) concentrations of T3 and rT3 (nanograms per dl) in umbilical plasma of dexamethasone-treated patients (106 +/- 13 and 360 +/- 35) were 3- and 2-fold and significantly higher (P less than 0.05) than those of the control group (39 +/- 6 and 195 +/- 19, respectively). No significant differences (P less than 0.05) were observed between the mean concentrations of TSH (microunits per ml) in maternal and umbilical plasma of dexamethasone-treated patients (2.5 +/- 0.5 and 3.0 +/- 1.0) and those of the control group (2.8 +/- 0.5 and 6.9 +/- 2.7, respectively). Under the conditions studied, no differences in the mean concentrations of amniotic fluid T4, T3, rT3, or TSH were observed between the two groups of patients (P less than 0.05). The increase of T3 and rT3 levels in umbilical plasma after dexamethasone administration indicates alteration in fetal thyroid economy.

Episodic secretion of human chorionic gonadotropin in early pregnancy.

The serum concentration of human chorionic gonadotropin (hCG) was measured at 10- to 60-minute intervals for 4-24 hours in 5 women at 5-8 weeks of pregnancy. hCG was found to be secreted episodically with pulses observed every 2-4 hours. The episodic secretion of hCG may have important implications to our understanding of both normal and abnormal reproduction.

Total and free thyroxine and triiodothyronine in normal and complicated pregnancy.

Serum concentrations of total and free thyroxine (T4 and FT4) and total and free triiodothyronine (T3 and FT3) were measured in normal pregnant women, in patients with toxemia of pregnancy, and in patients with gestational trophoblastic disease (GTD). In normal pregnancy, FT4 and FT3 levels remained normal while T4 and T3 levels were elevated. In patients with pre-eclampsia, the mean serum T3 concentration was significantly lower than that of normal pregnancy and the serum FT3 concentrations in three out of nine patients were below the normal pregnancy range. The mean serum T4 and FT4 concentrations in patients with pre-eclampsia were, however, significantly higher than those in normal pregnant women. In patients with GTD without signs of hyperthyroidism, the mean serum total and free T4 concentrations were 43 and 92% higher than those in normal pregnancy (P less than 0.02), and many patients had levels above the range of values observed in normal pregnant women. The mean serum total and free T3 concentrations in GTD patients without signs of hyperthyroidism were not different from those of normal pregnancy (P less than 0.05). In the single GTD patient with hyperthyroid crisis, the s. erum FT4 concentration was within the range seen in GTD patients without signs of hyperthyroidism. Her serum FT3 concentration was, however, much higher than the ranges in normal pregnancy or in GTD patients without clinical hyperthyroidism. Higher than normal FT4 levels were found in patients with and without elevated hCG levels.

Plasma cortisol and cortisone in pregnancies with normal and anencephalic fetuses.

Plasma cortisol (F), cortisone (E), and progesterone (P), were measured in the umbilical vein (UV), umiblical artery (UA), and maternal peripheral vein (MPV) of 17 normal patients, and of 8 patients carying anencephalic fetuses. The plasma F in MPV of patients undergoing vaginal delivery after labor of spontaneous onset was significantly higher than that of patients delivered by elective cesarean section, whereas the plasma F concentrations in the UA or UV of the 2 groups were not statistically different from each other. The anencephalic fetuses had UA plasma F and E concentrations which were significantly lower than those of normal fetuses, suggesting that a main portion of UA cortisol and cortisone originates in the fetal adrenal. The UV and MPV plasma F and E concentrations of patients carrying anencephalic fetuses did not differ, however, from those of normal patients, suggesting that these UV corticoids are derived mainly from maternal sources. The amniotic fluid cortisol levels of the patients carying anencephalic fetuses were lower than those observed in the normal pregnancies, suggesting that amniotic fluid cortisol is derived mainly from fetal sources.

Amniotic fluid reverse triiodothyronine in complicated pregnancy.

The concentrations of reverse triiodothyronine (3,3',5'-T3 or rT3) in amniotic fluid (AF) were measured by radioimmunoassay in 81 patients with various complications of pregnancy and in 39 normal pregnant patients at equivalent gestational age. In normal pregnancy, AFrT3 concentrations decreased with advancing gestational age. At 21-25, 26-30, 31-35, and 36-40 weeks of normal pregnancy, AFrT3 concentrations (mean +/- SE) were 353 +/- 62 (n = 6), 131 +/- 49 (n = 7), 94 +/- 25 (n = 14), and 93 +/- 5 (n = 20) ng/dl, respectively (ranges: 200-600, 57-350, 66-135, and 50-135). Both normal and supranormal values of AFrT3 were found in patients with complicated pregnancy. In patients with RH isoimmune disease, higher than normal AFrT3 concentrations were associated with seriously affected or gravely ill fetuses wheras normal AFrT3 concentrations predicted a more favorable outcome. There was a good correlation between AFrT3 and AF pigment (deltaOD450) levels (r = 0.70, P less than 0.001). In complicated pregnancy other than erythroblastosis fetalis, AFrT3 concentrations were not of any prognostic significance, and there was no correlation between AFrT3 and lecithin/spingomyelin ratio. The data suggest that AFrT3 determination may help in the assessment of the fetal condition in erythroblastosis fetalis.

Unoccupied and occupied estrogen receptors in myometrial cytosol and nuclei from nonpregnant and pregnant women.

Exchange assays have been developed and used to measure the total concentration of estrogen receptor sites (unoccupied and occupied with endogenous hormone) in the cytosol and nuclei of human myometrium during the menstrual cycle and in pregnancy at term, before and during labor. A major fraction of the nuclear receptors appear to be unoccupied (not complexed with estrogen). These sites were detected in both crude and highly purified myometrial nuclei, indicating that they are located in the nucleus and do not represent a cytoplasmic or other cellular contaminant. The distribution of estrogen receptors between the cytosol and the nucleus varied in pregnant and nonpregnant patients. In pregnant patients, the receptor was detected only in the nucleus, while in nonpregnant patients most of the receptor was found in the cytosol. The levels of total receptor were considerably lower (5 times) in pregnancy at term than during the menstrual cycle. No significant differences in cytosol receptor levels or in unoccupied nuclear receptor levels were observed between the proliferative and secretory phases of the cycle. However, the levels of occupied nuclear receptors were significantly higher in the proliferative than in the secretory phase. The levels of total and occupied nuclear receptors in pregnancy at term were similar to those found during the proliferative phase and appeared to decrease somewhat during labor, although the differences were not statistically significant.

Plasma estetrol as an index of fetal well-being.

Estetrol (15alpha-hydroxyestriol or E4) is considered to be a specific product of fetal liver and has been suggested as a good indicator of fetal well-being. The concentration of unconjugated estetrol (E4) was measured by rapid and specific radioimmunoassay in 1 ml of maternal plasma. E4 levels prior to the 18th week of pregnancy were often undetectable (smaller than 50 pg/ml). The mean plasma E4 level at term of 1.2 ng/ml was 7-fold higher than that observed at 24 weeks of gestation, and no diurnal variations were found. E4 levels in fetal plasma at term were 12-fold higher than those in maternal plasma and no fetal arterial venous differences were found. Umbilical vein but not maternal plasma levels of patients undergoing vaginal delivery were higher than those undergoing cesarean section (P smaller than 0.05) suggesting increased adrenal output of E4 precursors during labor. In patients with severe Rh-isoimmune disease plasma E4 levels were not helpful in assessing fetal well-being. However, in patients with chronic hypertension or pre-eclampsia, subnormal plasma E4 concentrations always preceded intrauterine fetal death. Plasma E4 appears to be a good indicator of fetal well-being in patients with hypertensive disease of pregnancy.

Suppression of prolactin and gonadotropin secretion in post-menopausal women by 2-hydroxyestrone.

An infusion of 2-hydroxyestrone given to estrogen primed post-menopausal women resulted in a rapid and total suppression of serum prolactin. Serum LH responded with an initial rise followed by a 30% decrease below baseline values. Serum FSH exhibited a significant suppression below preinfusion levels. The catechol estrogen had no effect on serum LH, FSH and PRL in post-menopausal women who were not pretreated with estrogens. This impact of 2-hydroxyestrone on pituitary hormone secretion provides for the physiological role of this non-uterotropic estrogen in the neuroendocrine mechanisms of the human.

Placental sulfatase deficiency: a case study.

A pregnancy with placental sulfatase deficiency was suspected when a 36-year-old patient at 41 weeks of gestation was found to have extremely low urinary estriol excretion and an otherwise normal prenatal course. The maternal plasma levels of estriol and estradiol 17-beta (E2) were extremely low and estetrol (E4) was undetectable (less than 40 pg/ml), whereas dehydroepiandrosterone sulfate (DS) was normal. THE AMNIOTIC Fluid DS concentration was 22-fold higher than the mean of normal pregnancy, while that of dehydroepiandrosterone (D) and androstenedione (A) was normal. Following intravenous infusion of 50 mg DS, no rise of plasma E2 was noted and plasma E4 levels remained undetectable. At 42 weeks of pregnancy, after induction of labor failed, a healthy male infant was delivered by cesarean section. The umbilical vein (UV) and umbilical artery (UA) levels of DS were extremely high, and those of E2 and E4 were subnormal. The UA level of A was normal and the levels of D and testosterone were slightly elevated. In vitro studies of placental microsomes and the 10,000 x g supernantant confirmed the diagnosis of placental sulfatase deficiency. The infant at 6 months of age had normal growth and development and normal peripheral plasma DS concentration.

Determinations of endogenous immunoreactive luteinizing hormone-releasing hormone in human plasma.

A specific and sensitive RIA was developed for measuring immunoreactive LHRH (IR-LHRH) in methanol acid-extracted human plasma. Heparinized blood samples were obtained from normal adult women and men, and the plasma was extracted with methanol, acidified, lyophilized, and stored at -20 C until assayed for LHRH. The lowest detectable levels of IR-LHRH in 1.0-3.5 ml methanol acid-extracted plasma ranged from 0.975-1.95 pg/assay tube, and recovery of synthetic LHRH from plasma averaged 88.6 +/- 2.4% (SE). Gel chromatographic separation analysis revealed comparable elution peaks for endogenous, tritiated, and synthetic LHRH. The plasma extract was also effective in evoking the release of LH and FSH in vitro using isolated rat hemipituitaries. IR-LHRH levels in human peripheral plasma rose 50-fold within seconds after an iv bolus injection of 100 micrograms synthetic LHRH with a return to baseline within 60 min. When the pattern of IR-LHRH secretion in peripheral plasma was studied, episodes of IR-LHRH rise were observed approximately every 60 min in both men and women. The physiochemical and biochemical properties of IR-LHRH suggest that it is an authentic LHRH. The presence of pulses of IR-LHRH suggests that its concentration in peripheral blood reflects changes in levels in the pituitary portal blood.

Adrenal steroids in maternal and cord blood after dexamethasone administration at midterm.

We undertook a study designed to evaluate whether it is feasible to suppress fetal adrenal secretion of androgens at mid-pregnancy by giving dexamethasone (DX) to the mother. Levels of DX and adrenal steroids were measured in maternal and cord plasma of 13 DX-treated and 16 untreated mothers undergoing abortion at 18-20 weeks of pregnancy. Maternal adrenal suppression was evidenced by a sharp fall of plasma cortisol (F), cortisone (E), corticosterone (B), and dehydroepiandrosterone sulfate (DHEA-S). However, in cord blood no fall of DHEA-S or corticosterone sulfate (BS) was found up to 20 hours after DX administration, and cord plasma ACTH remained detectable. The failure of DX to suppress the fetal adrenal at mid-pregnancy suggests that this drug would not be effective in the intrauterine treatment of congenital adrenal hyperplasia (C.A.H.).

The intraovarian sites of androgen and estrogen formation in women with normal and hyperandrogenic ovaries as judged by in vitro experiments.

The status of oocytes, the follicular fluid concentrations of steroids, and the in vitro steroidogenic capacities of stromal tissue, thecal tissue, and granulosa cells from a 15-yr-old girl with primary amenorrhea, ovarian hyperandrogenism, insulin-resistant diabetes mellitus, and acanthosis nigricans were compared to those from normal adult human ovaries. Most oocytes (95%) in the antral follicles recovered from the hyperandrogenic ovaries were degenerative, and the antral fluid levels of testosterone were 30- to 200-fold higher than those in normal ovaries. Granulosa cells from the hyperandrogenic ovaries produced mainly estradiol as did those from normal healthy follicles. The thecal tissues produced 2- to 6-fold more androgen than similar tissues from normal ovaries. However, the stroma from the hyperandrogenic ovaries produced 49- to 250-fold more testosterone than that generated by normal tissues. These data suggest that the removal of stromal tissue as well as follicular tissue from patients with certain types of hyperandrogenism may sometimes contribute to a reduction in androgen secretion.

Prenatal diagnosis of congenital adrenal hyperplasia.

The accurate prenatal diagnosis of 21-beta-hydroxylase deficiency, based on amniotic fluid levels of 17-hydroxyprogesterone, is documented for a fetus 14 1/2 weeks old. In addition, family HLA genotyping data are consistent with the purported linkage between the HLA locus and the locus for 21-beta-hydroxylase.