Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gonadotrophin (Gn), thyrotrophin (TSH) and prolactin (PRL) reserve was evaluated in patients (aged 12-26 years old) with beta thalassaemia. Abnormalities were detected in Gn reserve only. When compared with young adult controls, three of the four female patients and one of the two adult males had markedly impaired Gn responses to LH-releasing hormone (LHRH). Of the five prepubertal males, one had no Gn rise following LHRH, while responses in the other four patients were comparable to those in boys with delayed puberty. Only one adult male had an exaggerated LH response to LHRH. TSH and PRL dynamics were normal. No correlation could be found between the severity of the disturbance in the gonadal axis and the total number of blood transfusions. Our findings correlate best with the severity of the disease process itself.
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PMID:Gonadotrophin, thyrotrophin and prolactin reserve in beta thalassaemia. 35 99

To assess the influence of diminished oestrogen production on bone density, we studied 23 amenorrhoeic women and 20 controls (age range 16-29 years) divided into four groups: group 1: 6 patients with idopathic hypogonadotrophic hypogonadism with primary amenorrhoea (IHH); group 2: 5 patients with delayed puberty owing to thalassaemia major (TM); group 3: 12 patients with secondary hypothalamic amenorrhoea (HA); group 4: 20 women with normal menses (controls). Secondary sexual characteristics had developed in all except the women with TM. Groups 1 and 2 had never menstruated and group 3 had been amenorrhoeic for 6 months to 3 years. The control group was studied during the follicular phase of the cycle. None of the patients were taking oestrogens at the time of observation. Plasma concentrations were determined for 17 beta-oestradiol (E2), deidroepiandrosterone sulphate (DHEA-S), cortisol (F), prolactin (PRL), thyroid hormones (T3 and T4), and gonadotrophins (LH and FSH). Spinal bone mineral density (BMD g/cm2) was assessed by dual photon absorbiometry. BMD (mean +/- 1SD) was reduced in the patients (group 2: 0.920 +/- 0.95; group 1: 0.980 +/- 0.94; and group 3: 1.037 +/- 0.75) as compared with the controls (1.290 +/- 0.95) (P less than 0.01). In the three groups of patients, plasma E2 levels were lower than 50 pg/ml and were positively correlated with the BMD. As expected, plasma gonadotrophin levels were highly and significantly reduced (P less than 0.01) in the patients, compared with that of the controls. These results suggest that reduced spinal BMD in hypogonadic women may be related to the lack of oestrogenic influence on bone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Reduced spinal bone density in young women with amenorrhoea. 183 88

The aim of the present study was to investigate the effects of increased haemoglobin (Hb) levels on the thyroid function in patients with beta-thalassaemia major. Basal levels of thyroid hormones (T4, T3) and free thyroid hormones (fT4, fT3), basal TSH concentrations and the TSH responses to a TRH bolus (0.2 mg iv) were studied in ten euthyroid thalassaemic patients, aged 8 to 19 years, and in one 12 years-old thalassaemic girl with primary hypothyroidism. Five euthyroid thalassaemic patients (aged 8 to 12 years), as well as the hypothyroid thalassaemic girl, were prepubertal, whereas five euthyroid thalassaemic patients (aged 15 to 19 years) had delayed puberty. In each patient, the endocrine evaluation was carried out under conditions of low Hb levels (31 days after the last blood transfusion, mean Hb = 9.8 +/- 1.5 g/dl), and 11 days after the transfusion of 2 units packed red blood cells (PRBC). The latter increased significantly Hb concentrations in all the thalassaemic patients (mean Hb = 12.8 +/- 2.5 g/dl, P less than 0.001). Twelve normal prepubertal subjects, aged 6 to 11 years, served as the control group. Before the PRBC transfusion, basal T4, T3, fT4, fT3 and TSH concentrations were similar in euthyroid prepubertal thalassaemic patients (EPT) and in euthyroid patients with delayed puberty (EDPT), and were comparable to those in control subjects. The TSH responses to TRH (TSH peak, area and delta area) observed in EPT patients were similar to those in the EDPT group, but significantly higher in comparison with the normal children.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A rise in haemoglobin levels may enhance serum triiodothyronine (T3). Concentrations in prepubertal patients with beta-thalassaemia major. 212 31

Iron-chelating treatment is indicated in all children on prolonged transfusion therapy (i.e., chiefly patients with thalassemia and Blackfan-Diamond anemia). The purpose of iron-chelating treatment is to prevent the development of manifestations of iron overload including cardiac hemosiderosis and insulin-dependent diabetes mellitus (which are two potentially fatal complications), hepatic cirrhosis, hypoparathyroidism, hypothyroidism, and delayed puberty. Deferoxamine is the only effective iron-chelating agent and should be given in a daily dose of 40 mg/kg at initiation of the transfusion program. Administration is by subcutaneous infusions from 8 to 10 hours per day. The goal of iron-chelating treatment is to maintain serum ferritin levels between 500 and 1,000 ng/ml. This long-term treatment is a significant burden for patients and it can be hoped that non-toxic iron-chelating agents, active by mouth, will become available.
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PMID:[Iron chelation in children]. 268 51

Iron chelation therapy must be associated with the regular blood transfusions required for thalassaemia and other chronic anemias. We report here a study concerning 4 groups of patients, aged 6 to 28, regularly transfused at Necker Enfants-Malades hospital: a) 20 with thalassaemia major; b) 6 with thalassaemia intermedia; c) 2 with sickle cell disease and d) 2 with Blackfan-Diamond syndrome. The transfusion regimen consisting of monthly or quarterly transfusions varied as a function of the groups. Desferal was used in all patients. The dosage and the route of administration (IV, IM, SC) were adapted to the amount of iron transfused and to the nature of the disease. The serum ferritin level was considered as the indicator of the iron overload. Comparisons were established between the quantities of iron transfused, ferritin levels, and parameters such as dosage, route of administration and compliance to Desferal. During the period of study 3 patients died from cardiac failure due to transfusional hemosiderosis. Endocrine complications (diabetes 2 cases, hypocalcemia 3 cases, hypothyroidism 1 case and delayed puberty 7 cases) were observed. This high incidence of complications induced by post-transfusional iron overload has recently prompted us to improve the quality of chelation therapy through the use of the services of a specialized center where patients as well as their families can be trained more adequately in home care and self-treatment.
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PMID:[Treatment of post-transfusion iron overload by deferoxamine]. 273 4

Eight patients with beta-thalassemia who were given long-term treatment with combined multiple transfusions and chelation therapy underwent adrenal testing. The six male and two female patients ranged in age from 7 to 19 years. Six of eight patients had delayed bone ages and height greater than 2.5 SDs below the mean. Of the six patients more than 13 years of age, two had clinical evidence of isolated adrenarche and only one had evidence of true puberty. Cortisol levels were similar in patients and controls at zero time (10.6 +/- 1.8 micrograms/dL [292 +/- 50 nmol/L] vs 10.8 +/- 1.4 micrograms/dL [298 +/- 39 nmol/L]) and at 60 minutes (26.6 +/- 2.5 micrograms/dL [734 +/- 69 nmol/L] vs 24.9 +/- 1.9 micrograms/dL [687 +/- 52 nmol/L]) after insulin hypoglycemia (all values are the mean +/- SE). During an eight-hour infusion of ACTH, cortisol responses in the patients with thalassemia were not significantly different from those of controls. Baseline levels of the adrenal androgens dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) were significantly lower in the subjects with thalassemia compared with controls of similar bone age and pubertal status. The prolonged ACTH infusion caused a significant increase in the DHEA level (79.2 +/- 14.7 ng/dL [2.74 +/- 0.51 nmol/L] vs 538.6 +/- 38.1 ng/dL [18.67 +/- 4.79 nmol/L]) and the DHEA-S level (37.5 +/- 10.8 micrograms/dL [1.02 +/- 0.29 mumol/L] vs 70.5 +/- 18.3 micrograms/dL [1.19 +/- 0.50 mumol/L]) in the patients. The patients' peak stimulated levels of DHEA-S were significantly lower than those of the controls, whereas peak levels of DHEA were similar in the patients and the controls. These results indicate that combined multiple transfusions and chelation therapy preserve the integrity of the ACTH-cortisol axis in patients with thalassemia. The reduced levels of adrenal androgens, short stature, and delayed puberty noted in our patients suggest, however, that alternative approaches to the therapy of thalassemia are needed.
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PMID:Adrenal function in thalassemia major following long-term treatment with multiple transfusions and chelation therapy. Evidence for dissociation of cortisol and adrenal androgen secretion. 302 28

Endocrine studies were made on 23 female patients aged 13 to 29 years, with delayed puberty or primary amenorrhoea and beta thalassaemia major, and 12 healthy controls, of whom six were prepubertal and six were in Tanner's stage 3-4. Each patient and control received a single intravenous dose of 100 micrograms gonadotrophin releasing hormone (GnRH), and one week later, 10 U/kg body weight of human menopausal gonadotrophin (hMG) to stimulate ovarian function. The patients had decreased gonadotrophin reserves when compared with those of normal controls, only one of 23 patients had an intact luteinising hormone and follicle stimulating hormone response. Most of the thalassaemic patients with delayed puberty showed normal gonad response to human menopausal gonadotrophin (hMG), but three had very low responses, when compared with that of controls. The gonadal failure was even more severe in four of six patients with primary amenorrhoea. It is important to assess hypothalamic-pituitary-gonadal function in young women with beta thalassaemia major, so that those with glandular dysfunction may be started on replacement therapy.
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PMID:Gonadal function in patients with beta thalassaemia major. 312 28

Basal and L-dopa-stimulated secretion of growth hormone (GH) was investigated in 10 patients with beta-thalassaemia major. Five patients were prepubertal (chronological age 8 to 12 years), whereas 5 patients had delayed puberty (chronological age 15 to 19 years). Ten normal prepubertal subjects (chronological age 8 to 11 years) served as the control group. Each thalassaemic patient was subjected to two L-dopa tests (0.5 g L-dopa plus 0.7 mg/Kg body weight propranolol, orally): one was performed under conditions of low haemoglobin (Hb) levels (30 days after the last blood transfusion), and the second in the presence of increased Hb concentrations (10 days after the transfusion of packed red blood cells). Before the transfusion of packed red blood cells, basal GH concentrations were significantly higher in the patients with delayed puberty (4.3 +/- 1.6 ng/ml), than in prepubertal thalassaemic (1.8 +/- 0.9 ng/ml, p less than 0.05) and control (1.9 +/- 1.0 ng/ml, p less than 0.02) subjects. In contrast, the pituitary responsiveness to L-dopa, expressed as the relative maximum response for GH (GH delta %), was significantly higher in the latter two groups (8.5-fold, p less than 0.05, and 10.9-fold, p less than 0.02, respectively). The transfusion of packed red blood cells increased significantly Hb concentrations in both groups of thalassaemic patients (prepubertal +27%, p less than 0.05, delayed puberty +33%, p less than 0.025, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of increased haemoglobin levels on growth hormone (GH) secretion in beta-thalassaemia major: differences between prepubertal subjects and patients with delayed puberty. 324 42

A brief summary of the research carried out on the problem of geophagia is reported in this paper. Geophagia was a common finding among Turkish children and women in villages, associated with severe iron deficiency anemia in addition to zinc depletion. The syndrome characterized by geophagia, iron deficiency anemia, growth retardation, hypogonadism and zinc deficiency has been observed in both sexes in Turkey for several decades. Zinc deficiency has been also shown by our group in this syndrome. The decreased concentrations of zinc in serum, plasma, RBC, hair and urine were measured by atomic absorption spectrophotometer. Oral iron (both inorganic and radioactive iron) and zinc absorption tests were carried out with and without clay and revealed decreased iron and zinc absorption in some cases with prolonged geophagia. Therefore, malabsorption of iron and zinc was considered to be an additional and/or a new finding in the syndrome. Furthermore, Turkish clay most probably inhibits zinc absorption in a way similar to its inhibition of iron absorption. It was worthy of observation that some Turkish patients with this syndrome had a thalassemia-like appearance with similar skull-bone changes. Finally, growth retardation and delayed puberty were shown to be corrected by oral zinc treatment for 6-month terms. Linear growth and sexual maturation were found to be greater in the zinc-treated group than in the controls.
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PMID:Geophagia in Turkey: iron and zinc deficiency, iron and zinc absorption studies and response to treatment with zinc in geophagia cases. 665 8

Patients with beta-thalassemia major often have pubertal delay, the etiology of which has not been fully elucidated. We investigated the pituitary-gonadal response to short-term subcutaneous pulsatile gonadotropin-releasing hormone (GnRH) administration (150 ng/kg body weight every 120 min for 7 days) in five young males (aged 13.6-19.0 years) affected by beta-thalassemia major and presenting signs of delayed puberty. Immunoreactive and bioactive gonadotropin levels were determined and their isoform profiles were examined, before and after GnRH treatment, in a pool of samples collected every 15 min for 240 min. Testosterone, androstenedione, 17-hydroxyprogesterone, dehydroepiandrosterone and 17 beta-estradiol were measured as markers of gonadal function on days 0, 1, 3, 5 and 7 of treatment. Five patients (aged 16.9-26.8 years) with confirmed diagnosis of idiopathic hypogonadotropic hypogonadism who were starting pulsatile GnRH therapy were also studied in the same protocol. Increased sex steroid levels were observed in both groups as a result of treatment. On day 7, the thalassemic patients had increased bioactive luteinizing hormone (LH) and follide-stimulating hormone (FSH), although immunoreactive LH and FSH were comparable to day 0. Moreover, fewer acidic and more basic immunoreactive and bioactive isoforms were noted in LH profiles on day 7. Similar results were observed in hypogonadal patients, who also had increased immunoreactive LH and FSH values. We suggest that the early stage of delayed puberty in thalassemia might be characterized by a neuroendocrine dysfunction resulting in an impaired hypothalamic GnRH release, which is inadequate for a proper pituitary stimulation. Pulsatile GnRH treatment seems to re-establish partially the correct pituitary-gonadal function.
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PMID:Delayed puberty in males with beta-thalassemia major: pulsatile gonadotropin-releasing hormone administration induces changes in gonadotropin isoform profiles and an increase in sex steroids. 762 37


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