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Biomedical subjects

A Bellastella

Publications and source records attributed to A Bellastella.

At least 91 records · Page 5Linked to original sources
PubMed1987

Influence of blindness on plasma luteinizing hormone, follicle-stimulating hormone, prolactin, and testosterone levels in prepubertal boys.

The aim of this study was to determine if changes in LH, FSH, PRL, and testosterone (T) secretion occur in blind prepubertal boys. Eight blind and six normal boys, aged 7-10 yr, living at an institute for blind subjects in Naples, Italy, were studied. Each had a combined GnRH (100 micrograms) and TRH (200 micrograms) test at 0800 h after nocturnal rest. Plasma LH, FSH, PRL, and T levels were measured by RIA. The blind boys had basal plasma LH, FSH, and T levels significantly lower than those in the normal boys (P less than 0.01 for all three); plasma PRL basal levels were similar to those in the normal boys. The blind boys, moreover, had lower peak LH, FSH, and PRL (P less than 0.01 for all three peaks) levels in response to GnRH-TRH. Our results, similar to those found by others in patients with delayed puberty or with hypogonadotropic hypogonadism, suggest that light stimuli influence neuroendocrine-gonadal activity in humans, as in other mammals; and in blind prepubertal boys, impaired hormone secretion could cause a delay of pubertal development or more severe hypogonadism.

Blindness↗
PubMed1986

Thyroid localization in adult histiocytosis X.

Authors report on a rare case of thyroid involvement by histiocytosis X. A 27-yr-old man with diabetes insipidus and lung bullous disease of 2 yr duration was found to have thyroid gland infiltration by differentiated histiocytosis X. This was based on cytological findings consistent with the diagnosis, obtained by fine needle aspiration biopsy. Endocrine studies revealed altered hypothalamic-pituitary function accounted for by a hypothalamic lesion.

Adult↗
PubMed1986

Circannual variations of plasma testosterone, luteinizing hormone, follicle-stimulating hormone and prolactin in Klinefelter's syndrome.

To clarify the influence of primary testicular failure upon circannual hormone rhythmicity we have been studying, by cross-sectional design, 93 adult patients with Klinefelter's syndrome (KS) and 64 adult healthy males to look for evidence of circannual rhythms in testosterone (T), LH, FSH and PRL plasma concentrations. Plasma samples were taken from 08.00 to 09.00 h and all hormones were measured by radioimmunoassay. The data were assessed by the single cosinor method in order to obtain evidence for any significant rhythm and to estimate its parameters mesor, amplitude and acrophase. In the controls, annual rhythms were validated for the secretion of T (annual crest time in September), LH (annual crest time in February) and FSH (annual crest time in January), whereas PRL did not show a significant annual rhythm. In KS, significant circannual rhythms were validated for the secretion of T (annual crest time in April) and FSH (annual crest time in September), but not for LH and PRL secretion. Our results suggest that in KS the circannual hormone rhythmicity may be influenced by seminiferous tubule dysgenesis.

Adolescent↗
PubMed1986

Circannual variations of plasma thyrotropin in Klinefelter's syndrome.

The aim of this study was to explore the occurrence of abnormalities in the circannual thyrotropin (TSH) rhythm in Klinefelter's syndrome (KS). For 3 years, 69 healthy adult males and 73 patients with KS, usually living in Sardinia, were studied by a cross-sectional design. Plasma samples were taken between 08.00 and 09.00 h and TSH was radioimmunoassayed. First, the mean (+/- SD) of the data, grouped for each month of the year, was estimated to seek any macroscopic annual variation. Then, a cosine function was fitted to the single serially independent data by the single cosinor method in order to test for any statistically significant rhythm and, if the no-rhythm assumption is rejected, to describe the circannual parameters. Our patients showed circannual mean TSH concentrations lower than controls (p less than 0.001) without any statistically significant circannual rhythm, which was instead apparent in normal subjects with the annual crest time in December (95% CL November-February). Our results support the hypothesis that in KS the impaired TSH secretion may be related to abnormalities in the hypothalamic-pituitary coordination of the circannual rhythmicity of this hormone.

Adolescent↗
PubMed1985

Persistent TRH-induced growth hormone release after short-term and long-term L-thyroxine replacement therapy in primary congenital hypothyroidism.

No appreciable changes in plasma GH levels after TRH stimulation have been observed in normal subjects, whereas acute GH release has been reported in primary hypothyroidism and other pathophysiological states. To evaluate the effect of the T4 replacement therapy on TRH-induced GH release, 28 patient volunteers with primary congenital hypothyroidism (PCH), were studied before (11 subjects), after 1 month (nine subjects) and after long-term T4 replacement therapy (eight subjects). All patients underwent a TRH test with measurement of TSH, PRL and GH levels, and were compared to 28 age-matched normal subjects. An increase of plasma GH after TRH was found in 46% of patients without any therapy, in 67% of patients after one month of T4 administration and in 75% of patients after long-term therapy. No changes were observed in plasma GH levels in controls. The TSH response to TRH was inhibited and the response of PRL was reduced step by step by T4 replacement therapy in our patients with PCH. Our results suggest that: (i) Replacement T4 therapy in PCH does not abolish the paradoxical GH response to TRH, in spite of inhibiting the TSH response and reducing the exaggerated PRL response; (ii) the GH response to TRH in PCH seems to be unrelated to low thyroid hormone levels and/or to high TSH levels, but it could be due to changes in hypothalamic-pituitary regulation which are not improved by T4 replacement therapy.

Adolescent↗
PubMed1985

Male pseudohermaphroditism due to 3 beta-hydroxysteroid dehydrogenase-isomerase deficiency associated with atrial septal defect.

Male pseudohermaphroditism in a 6 month old boy, due to congenital 3 beta-hydroxysteroid dehydrogenase deficiency, associated with atrial septal defect, is reported. At 2 weeks he required therapy for severe dehydration and projectile vomiting. The parents were first cousins and one female sibling had died suddenly at 2 months. The patient presented with melanoderma, perineal hypospadias with testicles in a bifid scrotum and atrial septal defect (ostium secundum). Complete cytogenetic studies showed a 46,XY karyotype. Serum sodium ranged from 129 to 140 mEq/l and serum potassium from 5.1 to 4.6 mEq/l. Basal plasma hormonal studies showed normal androstenedione (delta 4A), decreased cortisol (F), slightly elevated ACTH, 17-hydroxy-progesterone (17-OH-P) and testosterone (T), and highly increased dehydroepiandrosterone-sulphate (DHEA-S) levels. ACTH stimulation increased and DXM suppression decreased the plasma levels of DHEA-S, 17-OH-P and T but not that of F; hCG stimulation during cortisone therapy did not change the levels of DHEA-S and T. Corticosteroid therapy normalized electrolyte levels and reduced melanoderma and hormonal hypersecretion. Moderately elevated plasma levels of 17-OH-P and T suggest a partial testicular 3 beta-HSD deficiency. The multifactorial inheritance and the relatively high prevalence of atrial septal defect vs the rarity of adrenal enzymatic defect suggest a causal association even if a common genetic factor cannot be excluded.

3-Hydroxysteroid Dehydrogenases↗
PubMed1984

Virilization syndrome in a young woman due to an androgen-secreting adenoma.

A virilization syndrome in a normally menstruated 20--year-old woman, due to adrenocortical tumor, is reported. Preoperative basal hormonal study showed normal plasma gonadotropins, androstenedione (A) and cortisol, slightly elevated testosterone (T), markedly increased urinary 17 ketosteroids (17KS) excretion and plasma dehydroepiandrosterone-sulfate (DHEA-S) levels. Thus DHEA-S was the major constituent of the androgen excess. Urinary 17KS and plasma DHEA-S did not change after ACTH, whereas increased after dexamethasone (DXM)-hCG administration. PRL and LH responses to TRH and LHRH tests were exaggerated. Echotomography, pneumoperitoneum radiography and selective adrenal venous angiography showed a tumor in the left adrenal gland. After the tumor removal all abnormalities were corrected. Light and electron microscopy showed well differentiation of the tumoral cells with typical ultrastructural characteristics of androgen-secreting tissue. It is concluded that the absence of amenorrhea and of LH suppression does not exclude the possibility of an androgen-secreting tumor. Moreover, the unusual finding of slightly elevated T value may be reported to enzymatic defect at the neoplastic cellular level. Furthermore the paradoxical DXM-hCG androgen response may be due to spontaneous variations in hormone secretion by the tumor or to cell receptors alteration.

Adenoma↗
PubMed1984

Circannual rhythms of plasma growth hormone, thyrotropin and thyroid hormones in prepuberty.

To clarify the occurrence of circannual GH, TSH, T4 and T3 rhythms in prepuberty we have been studying, for a four year period, 150 healthy subjects, aged 6-10, by cross-sectional design. Plasma samples were taken at 0800 h and all hormones were measured by RIA. The occurrence of any circannual rhythm was statistically investigated by the cosinor method. A significant rhythm was validated (P = 0.02) only in TSH secretion, with annual crest time in December; GH, T4, T3 did not show a circannual rhythm. Our results seem to strengthen the hypothesis that the thyroid hormones, at least before puberty, do not play an important role in the regulation of circannual TSH periodicity.

Child↗
PubMed1983

Circannual rhythms of plasma luteinizing hormone, follicle-stimulating hormone, testosterone, prolactin and cortisol in prepuberty.

For a period of four years we have been studying 106 healthy males and 66 healthy females, aged 6-10, by cross-sectional design, to look for evidence of a circannual rhythm in LH, FSH, testosterone, PRL, and cortisol secretion. Plasma samples were taken at 0800 h and all hormones were measured by RIA. A cosine function was fitted to the single data to indicate any significant circannual (about 1 year) rhythm and to estimate its parameters: mesor, amplitude, and acrophase. Annual changes were validated in the secretion of: LH (annual crest time in January in both sexes), testosterone (studied only in males, annual crest time in July), and PRL (significant rhythm only in females with annual crest time in March). FSH and cortisol did not show an annual rhythm in both sexes. Our data suggest that sex influences the circannual hormonal rhythms from prepuberty onwards.

Activity Cycles↗
PubMed1983

Change in circadian cortisol rhythmicity in patients with intracranial tumour.

To verify the influence of intracranial expanding processes on circadian cortisol rhythm, we studied its occurrence in 10 normal subjects, in 5 patients with extrasellar tumour, and in 3 patients with intracranial haematoma. All patients were tested every 4 h. Cortisol was measured by RIA. A cosine function was fitted to the data by mean cosinor method to evidence any rhythm and its parameters. A significant circadian rhythm was detected in the normal subjects with acrophase at 07.55 (07.15-08.25). The patients with extrasellar tumour and those with intracranial haematoma showed a lack of circadian rhythmicity due to a significant increase of cortisol levels at 20.00 and at 00.00, respectively. Our results suggest that study of the cortisol rhythm is useful, especially when an extrasellar tumour is suspected.

Adult↗
PubMed1980

[Effect of sex on annual variations in plasma LH and FSH levels in prepubertal subjects].

We studied, from 1977 to 1979, 61 females and 72 males (aged 6 to 10 years) in order to demonstrate the occurrence of FSH and LH circannual variations. The data were fitted a cosine function by least square method in order to describe any rhythm and to estimate its parameters:mesor, amplitude, acrophase. Our data suggest that in prepubertal age the behaviour of FSH secretion is different in two sexes, but without circannual rhythm. LH instead shows a statistically significant circannual rhythm in both groups, without differences in mean levels between the two sexes.

Female↗
PubMed1980

[Effect of sex on annual variations in GH response to insulin hypoglycemia in prepuberal subjects of small stature].

86 males and 66 females, aged 6 to 10 years, affected by short stature (SDs -2 according to Tanner), were investigated from 1977 to 1979 in order to evidence any circannual rhythm in the GH response to insulin test. The patients were hospitalized one week before the study starting and they observed the following life schedule:nocturnal rest from 2200 to 0600, meals at 0800, 1300, 1800. The insulin test (0,1 UI/Kg body weight) were administered at 0800. Plasma samples were taken before and after 20, 40, 60, 90 minutes. The single basal data and the peak were fitted a cosine function by least square method in order to describe amy rhythm and to estimate its parameters:mesor, amplitude, acrophase. A significative circannual rhythm in the GH response to insulin is present in the female subjects, with acrophase in December (-354.85 degrees +/- 21.93). Our study suggest that the sex may influence the circannual response of GH to insulin stimulus from prepubertal age.

Body Height↗
PubMed1980

[Annual variations in plasma testosterone levels in prepuberal subjects].

40 prepubertal boys, aged 6 to 10 years, were studied from 1977 to 1979 in order to evidence any circannual rhythm in the testosterone plasmatic levels. The patients observed in the following life schedule: nocturnal rest from 2200 to 0600 circa, meals at 0800, 1300, 1900. Plasma samples were taken at 0800 and testosterone was assayed by RIA. Testosterone data were fitted a cosine function, by least square method in order to describe any rhythm and to estimate its parameters:mesor, amplitude, acrophase. A significative circannual rhythm in the testosterone levels is present (P= 0.008) with Acrophase in July (-198.38 degrees +/- 18.26 ES). Our study suggests that a significative testosterone rhythm, with circannual periodicity, is present also in prepubertal age.

Child↗
PubMed1978

[Plasma LH, FSH, TSH, prolactin and cortisol during a combined test of pituitary reserve in prepubertal subjects with short stature].

The effect of a combined test (insulin, TRH, LHRH) on plasma concentrations of LH, FSH, PRL, Cortisol was studied in 18 normal subjects in prepubescent state and in 65 patients in prepubescent state with short stature. In 6 subjects with short stature there was no change of LH, and in 7 subjects with short stature there was no change of FSH. In conclusion the combined test for pituitary stimulation provides an useful method for localizing the lesion in disorders of hypothalamo-pituitary axis.

Child↗