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Biomedical subjects

Z Laron

Publications and source records attributed to Z Laron.

At least 199 records · Page 11Linked to original sources
PubMed1985

Plasma growth hormone response to synthetic GH-RH1-44 in 52 children and adults with growth hormone deficiency of various etiologies.

52 patients (42 children and 10 adults) with growth hormone deficiency (GHD), grouped into four diagnostic categories, and 6 children with constitutional short stature who served as controls were tested for plasma GH response to synthetic GH-RH1-44 given in an intravenous bolus. The response was classified into three degrees according to the magnitude of the maximal rise: Good, greater than 9 ng/ml; Partial, 3.1-9.0 ng/ml; None, less than or equal to 3 ng/ml. Among the GHD patients the highest response was observed in patients with partial growth hormone deficiency (PGHD), and 60% of the children with isolated GH deficiency (IGHD) showed an increase in plasma GH levels. Nevertheless, the response of the GHD patients was lower than that in the control group. In the children and adolescents with PGHD and IGHD the response was not age related. Among those with multiple pituitary hormone deficiencies-idiopathic (MPHD-ID) there was no response in the adolescents although a hypothalamic disorder had been documented by other tests. Among those with MPHD-organic (MPHD-ORG) the GH-RH stimulated GH secretion in the patients with glioma, who had received only irradiation treatment, and in the youngest of the patients with craniopharyngioma. Of the 10 young adults tested none showed a good response. It is concluded that GH-RH is useful in differentiating between GH deficiency of hypothalamic origin and that of pituitary origin, and in selecting those patients who might benefit from long-term treatment with GH-RH in the future.

Adolescent↗
PubMed1985

Delayed puberty and hypoplastic uterus associated with hyperprolactinemia: successful treatment with bromocriptine.

A 15-year-old girl referred because of primary amenorrhea was found to have a hypoplastic uterus and persistent hyperprolactinemia (72-110 ng/ml). The gonadotrophin-dependent pubertal signs, i.e. breast and vulvar development, were significantly retarded (Tanner stage 2-3) while sexual hair was well developed; bone age was 13 years. The endocrinological evaluation revealed gonadotrophin secretion (LH-basal: 0.85-1.25; peak after LH-RH: 10.4 mIU/ml; FSH-basal: 1.63-2.5; peak: 8.2 mIU/ml) and E2 levels (26-68 pg/ml) which were appropriate for Tanner stage 3. The high basal levels of PRL were nonresponsive to either stimulatory (TRH) or inhibitory (nomifensine) agents. CT scan of the brain suggested the presence of a pituitary microadenoma. Following therapy with bromocriptine (2.5 mg/day) plasma PRL levels dropped to normal (5-6.8 ng/ml) with an accompanying catch-up of pubertal development and linear growth and a marked increase in size of the uterus as documented by repeated ultrasonographic examinations. Menarche occurred 5 months after initiation of therapy, followed by regular menses thereafter. Repeated CT scan of the brain showed a decrease in the density and size of the still persisting lesion. This patient demonstrates that hyperprolactinemia can cause delayed puberty with a particular inhibitory effect on uterine growth and development.

Adenoma↗
PubMed1985

Some properties of the plasma hGH activity in patients with Laron-type dwarfism determined by a radioreceptor assay using human liver tissue.

A radioreceptor assay for human growth hormone (hGH) using the 100,000-g pellet of human liver tissue homogenates obtained from a 13-year-old male donor of a kidney transplantation is described. The dilution curves of the plasma hGH of 6 patients with Laron-type dwarfism (LTD) as well as those of the plasma hGH from 1 normal child and 2 acromegalic patients were all found to be parallel to the standard curve, suggesting that in the LTD syndrome the circulating hGH is biologically active.

Acromegaly↗
PubMed1985

Hepatitis associated with propylthiouracil treatment.

A 12-year-old girl with hyperthyroidism who had started treatment with propylthiouracil (PTU) 100 mg tid developed hepatitis. The drug was stopped, and the clinical and laboratory findings of hepatitis disappeared within a week. She was not receiving other drugs that could cause hepatic damage, and investigations for various viral agents were negative. This is the ninth report of PTU-induced hepatitis. The clinical picture is similar to that of viral hepatitis. Recovery usually occurs after withdrawal of the drug, but there have been two fatal cases of PTU-induced hepatitis.

Chemical and Drug Induced Liver Injury↗
PubMed1985

Effect of clonidine on plasma beta-endorphin, cortisol and growth hormone secretion in opiate-addicted subjects.

The effect of clonidine on plasma beta-endorphin, cortisol and growth hormone was studied in nine opiate-addicted subjects and seven control subjects aged 15 to 37 years. Clonidine, 0.15 mg, was administered orally in the morning, 18 to 24 h after the last administration of opioid drugs. Basal morning beta-endorphin levels were lower in the addicted than in the control subjects (3.76 +/- 0.8 vs. 7.42 +/- 1.2 pmol/l). Following the clonidine, there was an increase to normal values in the addicted subjects, but in the control subjects there was no change. Basal morning levels of cortisol were higher in the addicted subjects than in the controls (21.0 +/- 3.6 micrograms/dl vs. 13.0 +/- 1.2 microgram/dl, mean +/- SE). In control subjects clonidine induced a decrease of 50% in plasma cortisol, whereas in addicted subjects the decrease was not significant. It is hypothesized that in addicted subjects there is impaired activity of endogenous opioid peptides, leading to alteration in beta-endorphin and cortisol secretion.

Adolescent↗
PubMed1985

Comparison of the effect of insulin hypoglycemia and clonidine on secretion of growth hormone, cortisol and beta-endorphin in children and adolescents.

Plasma beta-endorphin, human growth hormone (hGH) and cortisol were measured concomitantly during insulin hypoglycemia (0.1 u/kg i.v.) or clonidine administration (0.075 mg/m2 orally) in children with idiopathic short stature. Whereas hypoglycemia raised plasma beta-endorphin levels, clonidine slightly decreased beta-endorphin in six subjects and had no effect in four. Cortisol levels increased following hypoglycemia and decreased markedly after clonidine. hGH increased to greater than 20 ng/ml in all but one subject. The findings are interpreted as further evidence that the hGH stimulation of clonidine is not stress-mediated.

Adolescent↗
PubMed1985

Human growth hormone gene deletion without antibody formation or growth arrest during treatment--a new disease entity?

Using restriction endonuclease analysis of genomic DNA hybridized to a human chorionic somatomammotropin (hCS) complementary (c)DNA probe, we studied four young Jewish patients with isolated growth hormone deficiency (IGHD), and 15 family members. One family originated in Iraq, two in Yemen and one in Iran. Each patient was homozygous for a deletion of approximately 7.5 kilobases, which included the hGH-N gene. Three of the deletions were associated with the same restriction fragment length polymorphism haplotype, while the deletion in the child of Iranian descent was associated with a different haplotype. All the patients were treated with three injections per week of pituitary human growth hormone (hGH) for periods of 2 1/2 to 14 1/2 years. All had a good growth response. Three reached normal and one almost normal height. Repeated serum analyses revealed absence of anti-hGH antibodies. Thus, the presently described patients differ from those previously reported from Switzerland, Argentina and Japan, all of whom developed anti-hGH antibodies during treatment, with resultant slowing or arresting of growth. Expression of heterozygosity in family members was variable with regard to stature, hGH reserve and insulin-like growth factor I (IGF-I) levels. It is hypothesized that hGH-N gene deletion is not the sole determinant of immune response during hGH treatment, and that the difference between the current series and other cases needs further investigation.

Autoantibodies↗
PubMed1985

Neuroendocrine study of a male infant with septo-optic dysplasia.

Septo-optic dysplasia includes abnormalities of the optic nerves and tracts with absence of the septum pellucidum. Most of the recently reported patients were deficient in growth hormone. We describe a male infant with septo-optic dysplasia in whom extensive endocrine evaluation revealed central diabetes insipidus, hypothalamic hypothyroidism and combined (hypothalamic-pituitary) hypoadrenalism, along with normal pituitary growth hormone reserve. This is the first reported case of a patient with septo-optic dysplasia who underwent corticotropin-releasing factor and growth hormone-releasing hormone stimulation.

Adrenal Glands↗
PubMed1985

Cytoplasmic islet cell antibodies in type I diabetics in Israel and their first-degree relatives.

The prevalence of islet cell antibodies (ICA) was studied in 172 newly diagnosed juveniles with Type I diabetes and in 300 unaffected first-degree relatives of 93 of these patients. Approximately 60% of the juvenile diabetics were ICA-positive at onset. Most of these patients gradually lost their antibodies, although two patients remained positive for ICA for periods up to 5 years. Complement-fixing ICA (CF-ICA) were found in 20% of the patients having ICA at onset. Disappearance of CF-ICA was rapid, with all patients showing negative values by the end of the second year. In 19 patients ICA intermittently disappeared and reappeared. ICA were found in 17 healthy family members (7 parents and 10 siblings). Although Type I diabetes is relatively rare in both the Jewish and Arab populations in Israel, these findings indicate that it has a similar autoimmune pathogenesis to that found in other populations around the world. The percentage of patients with ICA was as reported elsewhere, but that of CF-ICA was lower; its similarity with that reported for a Mediterranean population in France suggests a possible link with ethnic origin.

Adolescent↗
PubMed1985

Comparison of metabolic and psychological parameters during continuous subcutaneous insulin infusion and intensified conventional insulin treatment in type I diabetic patients.

Two methods of insulin treatment--intensified conventional therapy (ICT) of three to four daily injections and continuous s.c. insulin infusion (CSII)--were compared in nine patients with insulin-dependent diabetes mellitus (mean age +/- SD 29.4 +/- 5.6 years; duration of diabetes 14.6 +/- 2.9 years). Patients followed each regimen for 3 to 4 months. Under both regimens hemoglobin A1 (HbA1) levels were lower than those recorded previously, but under CSII the mean HbA1 and glucose levels were significantly lower than under ICT (7.8 +/- 0.1 vs. 8.9 +/- 0.2% for HbA1 and 136 +/- 40 vs. 155 +/- 60 mg/dl for blood glucose, P less than 0.001). There was no difference in the frequency of blood glucose levels less than 60 mg/dl, but under CSII hypoglycemic symptoms appeared at lower glucose levels. There was no marked difference between the two regimens regarding scores for depression and anxiety and other psychological parameters, but patients who chose to continue treatment with CSII following completion of the study had previously manifested a significantly higher degree of distress symptoms, which had been reduced during the study. CSII was preferred by some patients because of the superior metabolic control achieved and the greater flexibility in time and size of meals permitted, but was rejected by others because of technical failures and bulkiness of the device. It is concluded that metabolic control can be improved by either regimen, but external pumps must be further miniaturized and technical failures eliminated before CSIII is acceptable to larger numbers of patients.

Adult↗
PubMed1985

[Nanism with high values of GH and no generation of somatomedin after hGH (Laron's syndrome). Clinico-biochemical study of 8 cases].

Eight familial cases with Laron type dwarfism (LTD) are presented. An autosomic recessive transmission seems to be possible with clear predominance in females (6/2). This syndrome first described in Jewish people is probably frequent in our country, with clear historic Jewish antecedents in some of our cases. Some features like prenatal growth deficiency, disproportion between face and calvarium and high levels of inmunoreactive GH distinguish clearly LTD from isolated GH-deficiency. The incapability of hGH to increase low somatomedin activity confirms diagnosis. Moreover low or null nitrogen retention after hGH excludes an inactive GH as a cause of dwarfism.

Adult↗
PubMed1984

Effect of aging on human plasma growth hormone response to clonidine.

The effect of the oral administration of 0.150 mg/m2 clonidine on the plasma level of human growth hormone (hGH) was studied in 53 adults (25 males and 28 females) aged from 28 to 68 years, of which 15 were healthy volunteers and 38 were hypertensive. Both the normal and hypertensive subjects of both sexes showed an age-related responsiveness of hGH to clonidine, with a normal or partial response in the younger subjects and blunting or lack of response in the more elderly subjects. In the females the blunting of the hGH response appeared at an earlier age than in the males. It is speculated that an alteration in the sensitivity of the central alpha-adrenergic receptors and a decrease in the sex steroid hormones may account for the progressive reduction in hGH secretion with advancing age.

Adult↗
PubMed1984

Plasma growth hormone response to oral clonidine as compared to insulin hypoglycemia in obese children and adolescents.

The response of plasma growth hormone (hGH) to a single oral dose of clonidine (0.15 mg/m2) was compared with that obtained with insulin hypoglycemia (ITT) induced by administration of double the usual dose (0.2 U/kg i.v.) in 13 obese subjects aged 5-17 years (7 males, 6 females) with a subscapular skinfold greater than 20 mm and a weight greater than 2 SD of the median. Six healthy subjects (3 males, 3 females), aged 8-14 years who served as controls received the usual dose of 0.1 U/kg i.v. in the ITT. Clonidine induced an increase of more than 10 ng/ml in the plasma hGH levels in 10 (4 males, 6 females) of the 13 obese subjects and in all of the healthy controls, with peak levels ranging from 14.3 to 31.0 ng/ml (m +/- SD 21.0 +/- 5.2 ng/ml); the ITT elicited a similar rise in only 6 of the 13 subjects and 3 of the healthy controls, with peak levels ranging from 9.8 to 20.0 ng/ml (m +/- SD 14.4 +/- 4.5 ng/ml). Clonidine decreased plasma insulin levels in all the obese female subjects (by a mean of 65%) whereas in the obese males the insulin pattern was variable. There was no change in blood glucose levels following the administration of clonidine; during the ITT all subjects showed a decrease to less than 50 mg/dl. Blood pressure decreased by a mean of 20 mmHg during the clonidine test. This study demonstrates that clonidine is a more effective hGH stimulus than insulin induced hypoglycemia in normal and in obese children and that the lower hGH secretion of the obese is confirmed by the clonidine test.

Adolescent↗
PubMed1984

Differential diagnosis between hypothalamic and pituitary hGH deficiency with the aid of synthetic GH-RH 1-44.

Synthetic GH-RH 1-44 administered as an intravenous bolus (1 microgram/kg) evoked a marked hGH rise (greater than 20 ng/ml) in three children with constitutional short stature and in two of eight children diagnosed as having hGH deficiency by insulin hypoglycaemia and/or clonidine tests. As judged by the intensity of the hGH response to the dose employed and the peak time, GH-RH 1-44 may be as potent as GH-RH 1-40 in children. It is concluded that GH-RH is an important addition to the endocrine armamentarium, providing the means for differentiation between hypothalamic and pituitary hGH deficiency in a simple test which is devoid of side effects.

Adolescent↗
PubMed1984

Total deficiency of corticosteroid-binding globulin.

An obese 15-year-old boy of Jewish Iranian origin who is the offspring of consanguineous parents was found to have very low levels of total cortisol in the plasma. Investigation of the family revealed a complete lack of cortisol-binding-globulin (CBG) in the proband and a sister, evidently the first cases of total CBG deficiency to be reported. The parents and a brother were found to have half the normal levels. This study indicates that CBG deficiency, a benign condition, is compatible with a codominant or recessive autosomal trait inheritance.

Adolescent↗
PubMed1984

Treatment of precocious puberty with LHRH analogue in combination with cyproterone acetate-further experience.

Six girls and one boy with precocious puberty were treated with a superactive LHRH analogue (D-TRP6-LHRH) for periods ranging from 1 year to 2 years and 3 months. In the first phase of the treatment it was administered in combination with cyproterone acetate (CyA) to counteract an early stimulatory effect until inhibition of gonadotrophin secretion was achieved. The gonadotrophin-dependent signs i.e. gonadarche, showed sustained arrest and even regression. Gonadal sex steroids decreased but the adrenal androgens were unaffected. In four patients who showed progression of the angrogen-dependent signs (adrenarche), despite suppression of gonadotrophins, increasing the dosage of the LHRH analogue was ineffective and combined therapy with CyA was reinstituted in three of them because of accelerated growth and bone maturation. It is concluded that at present the treatment of choice for precocious puberty is the daily administration of a superactive LHRH analogue such as D-TRP6-LHRH, together with CyA in the initial stage, and at a later state if adrenarche progresses too rapidly.

Androgens↗