Search PubMed⌕ Search

Biomedical subjects

I D Hay

Publications and source records attributed to I D Hay.

At least 109 records · Page 6Linked to original sources
PubMed1984

Contrasting effects of subcutaneous pulsatile GnRH therapy in congenital adrenal hypoplasia and Kallmann's syndrome.

A patient with congenital adrenal hypoplasia (AH) and hypogonadotrophic hypogonadism was treated with pulsatile subcutaneous GnRH therapy for 16 weeks in an attempt to induce puberty. No rise in serum LH or FSH concentrations occurred despite increasing doses of GnRH (2.8 micrograms/pulse-22.4 micrograms/pulse). In contrast a similar programme of therapy successfully initiated the biochemical changes of puberty in a patient with Kallmann's syndrome. Both patients before therapy had low basal serum LH and FSH concentrations with blunted LH and FSH responses to GnRH stimulation. After 1 week, serum LH and FSH rose into the normal adult range in the patient with Kallmann's syndrome. This study fails to confirm a previous report which suggested that intermittent low dose GnRH therapy may be of value in inducing puberty in AH. The reasons for the difference of pituitary responsiveness to GnRH in AH and Kallmann's syndrome are unclear at present.

Adrenal Glands↗
PubMed1983

Familial resistance to thyroid hormone associated with decreased transport across the plasma membrane.

Resistance to thyroid hormone associated with a defect in hormone transport across the plasma membrane occurred in a 74-year-old eumetabolic woman. She had marked elevations in the serum levels of total thyroxine (T4), free T4, and reverse triiodothyronine (rT3). Levels of T3 were only minimally increased. The hyperthyroxinemia was thyrotrophin (TSH) dependent, but was not due to an alteration in the binding of T4 to serum proteins. Refractoriness to thyroxine was only partial, as indicated by the increase in the basal metabolic rate and suppression of the response of TSH to thyrotrophin-releasing hormone (TRH) after the administration of L-thyroxine, 600 micrograms daily, for 3 weeks. The basic abnormality involved a selective decrease of T4 plasma membrane transport shown by in-vitro studies of erythrocytes. Screening of family members showed similar biochemical abnormalities in two other relatives. In this familial syndrome characterized by eumetabolic hyperthyroxinemia, the alteration of thyroid hormone metabolism seems to involve primarily the partition of T4 between the intra- and extracellular spaces.

Adult↗
PubMed1982

Effects of growth hormone, glucose and insulin on the factor VIII complex.

The relationship of growth hormone (GH) to the factor VIII complex (VIIIC, VIIIRAg and VIIIRRCo) was investigated. No correlation between basal levels of GH and factor VIII assays was found in 23 subjects. No significant change in factor VIII assays was observed after GH suppression by oral glucose or bromocriptine. After insulin-induced hypoglycaemic all three factor VIII assays rose and fell in parallel with GH. However, after exercise the rise in VIIIC and VIIIRAg preceded the rise in GH; and no changes in factor VIII assays were observed after administration of thyrotrophin releasing hormone (TRH) (releasing endogenous GH) or exogenous GH. These findings do not support a role for GH in the regulation of plasma levels of VIIIC, VIIIRAg or VIIIRRCo.

Antigens↗
PubMed1982

Cryosurgery or microsurgery in the management of acromegaly.

Fifty-six patients with growth hormone-secreting pituitary adenomas, 28 treated by cryoablation and 28 by microsurgery, have been followed up from three to eight years. Mean serum growth hormone concentrations were less than 10 mU/L in 19 patients (68%) after microsurgery as compared with seven (25%) after cryosurgery. Hypopituitarism and operative complications were more frequent after cryosurgery. Transsphenoidal microsurgery was particularly successful in reducing growth hormone secretion without impairing normal pituitary function, when the patient had not been previously treated by another method.

Acromegaly↗
PubMed1982

Serum immunoreactive melatonin in boys with delayed puberty.

Serum immunoreactive melatonin was measured in thirty-three male subjects with delayed puberty, thirty of whom had simple (idiopathic) delayed puberty (SDP) and three of whom were GH deficient. The results were compared with a control population of twenty-six subjects. Significantly elevated values of serum melatonin were demonstrated in both groups of abnormal subjects as compared with the control population (P less than 0.0001). No significant fall of serum melatonin was noted in the subjects with simple pubertal delay prior to the onset of puberty. However, there was a significant fall of serum melatonin in these subjects between mid and late puberty (P less than 0.025). The results suggest that whilst melatonin may inhibit puberty, a fall in serum levels is not essential for the commencement of puberty in man.

Adolescent↗
PubMed1982

Radioiodine-induced hypothyroidism in Graves' disease: factors associated.

A retrospective analysis was done of the records of 454 patients who received their first I-131 treatment for Graves' disease during six periods covering 1951 to 1978. In the earliest group, 3% of patients were hypothyroid 3 mo after I-131 use, and 40% were hypothyroid at 1 yr. In the most recent group, 36% of patients were hypothyroid at 3 mo and 91% were myxedematous at 1 yr. Although no obvious trends were noted, whether in the number of patients pretreated with thionamide drugs, in the mean 24-hr I-131 uptake, or in the calculated dose of I-131 (muCi/estimated gram of thyroid tissue) during the years of the study, the initial mean dose of I-131 administered increased from 8.1 mCi in the earliest group to 13.8 mCi in the latest group. Concurrently, estimates of gland size increased from a mean of 26 g in the first group to 43 g in the last. If, in patients with Graves' disease, the thyroid gland size did not truly increase during the years of the study, the increasing occurrence of early hypothyroidism seen after I-131 use may reflect the conscious or unconscious decision to use larger doses of I-131 calculated on the basis of inflated estimates of thyroid gland weight.

Adult↗
PubMed1981

Simultaneous determination of D- and L-thyroxine in human serum by liquid chromatography with electrochemical detection.

A method for the determination of D- and L-thyroxine in human serum is described. The method involves extraction of thyroxine from serum and the separation of thyroxine enantiomers on a reversed-phase, high-performance liquid chromatographic column by use of a chiral eluent containing L-proline and cupric sulfate. Satisfactory resolution of the enantiomers of thyroxine, triiodothyronine, and reverse triiodothyronine can be achieved in 12 min and, employing amperometric detection to monitor the separation, the detection limit for serum thyroxine is in the range of 1--3 ng per injected sample.

Chromatography, High Pressure Liquid↗
PubMed1981

Familial cytomegalic adrenocortical hypoplasia: an X-linked syndrome of pubertal failure.

Five boys with familial cytomegalic adrenocortical hypoplasia have been followed up for an average of 19 years. Despite treatment with replacement corticosteroids, all 5 failed to show a spontaneous onset of puberty and, when assessed at ages 13 to 19 years, all had both sexual infantilism and skeletal immaturity. Hypogonadism was confirmed by low levels of plasma testosterone, and pituitary reserve of gonadotrophin was shown to be inadequate by testing with gonadotrophin-releasing hormone. Two boys, both with adequate testosterone output on human chorionic gonadotrophin stimulation, were given gonadotrophin therapy, whereas the other 3 were treated with parenterally administered testosterone. With treatment, all 5 patients showed advances in pubertal staging. Although the mechanism of the hypogonadotropism remains unclear, the association of hypogonadotrophic hypogonadism with familial cytomegalic adrenocortical hypoplasia appears to be a constant one and may be considered as a treatable inherited syndrome of pubertal failure.

Adolescent↗
PubMed1980

Semi-quantitative analysis of the bone scan in acromegaly: correlation with human growth hormone values.

99Tcm-HEDP bone scans were obtained in 20 acromegalic patients. Twelve patients had active disease with elevated basal serum human growth hormone (HGH) levels. Eight patients were in clinical and biochemical remission. The bone scans, assessed independently by three observers, showed features characteristic of metabolic bone disease in patients with active acromegaly. The metabolic index derived from the scan correlated well with serum HGH levels (R = 0.71, p < 0.002). The bone scan may accurately reflect oversecretion of HGH and is of potential value in the assessment of patients with acromegaly.

Acromegaly↗
PubMed1980

Adrenal scintigraphy: comparison of the Anger tomoigraphic scanner and the large-field gamma camera: concise communication.

To evaluate observer performance in adrenal scintigraphy with two different imaging instruments and to assess the requirement for computer processing in routine adrenal imaging, gamma-camera images (analog and computer processed) and Anger tomoscanner studies were independently interpreted by three observers. Thirty-eight pairs of images were used for the analysis of the receiver operating characteristic (ROC) curve in comparing the tomoscanner with the large-field gamma camera, and 44 pairs of images were used for the comparison of the gamma camera analog images with computer-processed images. ROC analysis demonstrated a higher detection rate for the tomographic images. The computer-processed images did not improve adrenal detection. When each case was considered individually, the tomoiscanner was preferred in 37% of cases, and in 50% of cases, both instruments were considered to be equaly valuable.

Adolescent↗
PubMed1979

Semi-quantitative interpretation of the bone scan in metabolic bone disease: definition and validation of the metabolic index.

Certain easily recognisable features are commonly seen in the bone scans of patients with metabolic bone disorders. Seven such features have been numerically graded by three independent observers in the scans of 100 patients with metabolic bone disease and of 50 control subjects. The total score for each patient is defined as the metabolic index. The mean metabolic index for each group of patients with metabolic bone disease is significantly greater than that for the control group (P less than 0.001).

Bone Diseases↗
PubMed1979

Metoclopramide stimulation: a test of growth hormone reserve in adolescent males.

A comparison was made between the growth hormone (GH) response to metoclopramide ('Maxolon'--Beecham Laboratories) and insulin induced hypoglycaemia in thirty-five short adolescent males. Both tests initially caused adequate release of GH from the pituitary gland in 86% of those subjects who had normal GH reserve. The peak growth hormone responses of the two tests were similar in magnitude and were strongly correlated (r = 0.80, P less than 0.001). Both tests raised serum GH to a similar degree in twenty-nine out of the thirty-five boys (83%), but four boys who responded satisfactorily to hypoglycaemia failed to respond to metoclopramide (MCP) stimulation, and two boys who failed to respond to hypoglycaemia responded satisfactorily to MCP stimulation. MCP stimulation does not require prior preparation of the patient and is relatively free of side effects. Consequently, it is suggested that MCP stimulation may be a useful 1 hour out-patient test for growth hormone deficiency in this relatively common group of patients.

Adolescent↗
PubMed1979

Metoclopramide induced growth hormone release in hypogonadal males.

The growth hormone (GH) response to 10 mg intravenous metoclopramide (MCP) ('Maxolon'--Beecham Laboratories) was determined in ten hypogonadal adult males. All the subjects responded with a peak growth hormone level greater than 14 mU/l within 1 hour of administration of MCP. Seven normal adult males did not respond to MCP administration. It is concluded that MCP stimulation may be a useful test for both prolactin and growth hormone reserve in hypogonadal males.

Adolescent↗