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Biomedical subjects

J W Finkelstein

Publications and source records attributed to J W Finkelstein.

At least 37 records · Page 2Linked to original sources
PubMed1977

Endocrine and cytogenetic studies in a patient with Turner's phenotype and a ring chromosome.

A 27-year-old woman with secondary amenorrhea and some of the somatic stigmata of Turner's syndrome was found to have a ring chromosome. Laparoscopy and ovarian biopsy showed hypoplastic ovaries and an absence of primordial follicles. Endocrine evaluation showed a normal 24-h mean LH level (12.5 mIU/ml), an elevated FSH level (28 mIU/ml) and a normal plasma estradiol level (64 pg/ml). The augmented FSH and normal LH response to LH-RH is similar to what is found in men with germinal cell aplasia (Sertoli-cell only). The synchronous initiations of normal LH and abnormally augmented FSH secretory episodes in this patient suggests the absence or decrease of some factor normally produced by the ovarian follicle which modulates the release of FSH in response to LH-RH.

Adult↗
PubMed1976

Endocrine studies in a phenotypic girl with XY gonadal agenesis.

An 18-year-old phenotypic girl with XY gonadal agenesis had endocrine studies. The patient had a small amount of sexual hair, a slightly enlarged clitoris, normal labia and no posterior fusion. Her vagina was of normal length, but no cervix was palpable. At laparoscopy, no gonads, uterus or fallopian tubes were identified. The buccal smear was chromatin negative and the karyotype was 46XY. The 24 h LH plasma pattern was qualitatively similar to that found in normal late pubertal subjects, but the values were in the castrate range. The 24h mean plasma concentrations of testosterone and dihydrotestosterone were 16.4 ng/dl and 14.2 ng/dl, respectively. Urinary estrogen excretion was 15 and 19 mug/day. These clinical and endocrine findings suggest that the patient was a genetic male in whom Mullerian regression occurred normally; however, the testes probably ceased functioning early in gestation preventing normal development of the Wolffian system. This set of events resulted in agenesis of the gonaductal system and female external genitalia. The patient represents the second example of this variation of male pseudohermaphroditism associated with XY gonadal agenesis.

Adolescent↗
PubMed1976

Clinical and laboratory heterogeneity in idiopathic hypogonadotropic hypogonadism.

Six young men with idiopathic hypogonadotropic hypogonadism had 24-h frequent blood sampling studies for measurement of LH, FSH and testosterone. Five of the patients had LH and FSH measured after administration of 100 mug LH-RH during waking and then during sleep. Four of the patients had testicular biopsies performed. The results of the present studies showed that 4 of the patients had no evidence of episodic LH, FSH, or testosterone secretion. The two patients who showed significant sleep related pulses of LH had the highest 24 h mean testosterone concentrations, the best responses to exogenous LH-RH and the most differentiated testicular biopsies. Sleep had no effect on the release of LH or FSH in response to LH-RH. These sutdies suggest that the clinical and laboratory heterogeneity of idiopathic hypogonadotropic hypogonadism may be the result of differences in the degree of endogenous LH-RH deficiency.

Adult↗
PubMed1976

Human puberty: 24-hour estradiol in pubertal girls.

Plasma luteinizing hormone, follicle-stimulating hormone, and estradiol were measured at 20-minute intervals for 24-hours in seven pubertal premenarchal girls whose sleep was monitored polygraphically. A circadian variation in plasma estradiol was demonstrated with the highest values occurring during the day (1400-1600 hours) and lowest values during sleep, a time when gonadotropin secretion was augmented.

Adolescent↗
PubMed1975

Twenty-four hour prolactin (PRL) secretory patterns during pregnancy.

To determine if the central nervous system "program" controlling PRL secretion is operative during pregnancy, three pregnant women (12th, 20th and 32nd week of gestation) had 24-hour, 20-minute interval plasma sampling and polygraphic monitoring of nocturnal sleep. All three subjects showed episodic PRL secretion during waking which became augmented during nocturnal sleep. Since the number of "major" PRL secretory episodes was similar to normals, the increased PRL levels were most probably achieved by increased secretion per secretory episode. These findings suggest that during pregnancy, the PRL sleep related secretory "program" is maintained in a qualitative manner, albeit at a higher set-point.

Adult↗
PubMed1974

Hypothalamic-pituitary function in diverse hyperprolactinemic states.

Prolactin secretion in normal adults is characterized by periods of episodic secretion which increase in magnitude during sleep. In this study, we report the 24-h mean prolactin concentrations, prolactin secretory patterns, and associated pituitary hormone function in nine patients (seven women and two men) with hyperprolactinemia of diverse etiologies. Four of the women and one of the men had clinically demonstrable pituitary tumors, one boy had a hypothalamic tumor, and the three other women had "functional" hyperprolactinemia. The 24-h mean prolactin concentrations derived from averaging the 20-min interval samples for 24 h ranged from 28.6 to 1,220 ng/ml. The plasma prolactin patterns in these patients showed persistence of episodic secretion in all and loss of the normal sleep-wake difference in plasma prolactin in seven of nine. Three of the patients with galactorrhea and comparable 24-h mean prolactin concentrations (58.3, 59.7, and 64.3 ng/ml) showed similar prolactin secretory patterns despite different etiologic mechanisms. Evaluation of the secretory patterns of luteinizing hormone (LH) in these patients showed loss of normal pulsatile LH release and a low 24-h mean LH concentration in the patient with the pituitary tumor, while the two patients without clinically demonstrable pituitary tumors ("post-pill" galactorrhea and "idiopathic" galactorrhea) showed normal LH secretory patterns and 24-h mean LH concentrations. The 24-h mean cortisol concentrations and secretory patterns were normal in five of the seven patients who had these parameters measured. The patient with the hypothalamic tumor had a low 24-h mean cortisol concentration and production rate and absent response to metyrapone. The patient with "idiopathic" galactorrhea had an elevated 24-h mean cortisol concentration but normal cortisol production rate and urinary 17-hydroxycorticoid excretion. Growth hormone secretion was abnormal in four of the patients (one with the hypothalamic tumor and three with pituitary tumors). Thyrotropin-releasing hormone (TRH) administration in four patients resulted in normal TSH release in two patients (one of whom developed galactorrhea after the test), an absent response in the patient with the hypothalamic tumor, and a blunted response in one of the women with a pituitary tumor. The two men had low 24-h mean plasma testosterone concentrations (69 and 30 ng/100 ml) and symptoms of impotence and loss of libido. Five of the women (four with pituitary tumors and one with Chiari-Frommel syndrome) had either low 24-h mean LH concentrations, abnormal LH secretory patterns, or both. These data indicate that patients with hyperprolactinemia encompassing a varied etiological range frequently show loss of the normal sleep-associated increase in prolactin secretion as well as abnormalities in the regulation of the other hypothalamic pituitary-regulated hormones. The finding that the abnormalities in LH, growth hormone, thyrotropin, and cortisol (adrenocorticotrophic) secretion were almost uniformly confined to the patients with the clinically demonstrable hypothalamic or pituitary tumors suggests that the size of the lesion is the critical factor.

17-Hydroxycorticosteroids↗
PubMed1974

Human puberty. Simultaneous augmented secretion of luteinizing hormone and testosterone during sleep.

Plasma luteinizing hormone (LH) and testosterone (T) were measured by radioimmunoassay in nine pubertal boys and three sexually mature young men at 20-min intervals for 24 h. Plasma LH and T were also measured in one boy during a delayed sleep onset study. Polygraphic monitoring was carried out to identify precisely sleep onset. Wakefulness, and specific sleep stages. In all nine pubertal boys the plasma T concentration fluctuated and was significantly higher during normal nocturnal sleep as compared to daytime waking. This increased T secretion during sleep was temporally linked to the characteristic pubertal sleep augmentation of LH secretion. To define further the relationship of this increased T secretion to sleep, plasma LH and T were also measured in three of the pubertal boys after acute (1-day) reversal of the sleep-wake cycle. One of these boys was also studied after 3 days of sleep-wake cycle reversal. The results of these studies showed that plasma T was now augmented during the reversed daytime sleep period; the mean T concentrations during this period were significantly higher (P < 0.001) than during nocturnal waking in all four studies. Measurement of plasma LH and T in the three sexually mature young men showed episodic secretion of LH and T during both waking and sleep periods; there was no consistent significant augmentation of LH or T secretion during sleep. This study demonstrates that (a) in normal pubertal boys and sexually mature young men plasma T fluctuates episodically; (b) there is marked augmentation of T secretion during sleep in pubertal boys, which is dependent on increased LH secretion; (c) this pubertal LH-T secretory "program" is dependent on sleep, since it shifts with delayed sleep onset and reversal of the sleep-wake cycle; and (d) this demonstrable tropic effect of LH on T is evident only during puberty, since sexually mature young men fail to show any consistent relationship between LH and T secretion either awake or asleep.

Adolescent↗