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)

Growth retardation in children with thalassaemia major is multifactorial. We studied the growth hormone (GH) response to provocation by clonidine and glucagon, measured the circulating concentrations of insulin, insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP3), and ferritin, and evaluated the spontaneous nocturnal (12 h) GH secretion in prepubertal patients with thalassaemia and age-matched children with constitutional short stature (CSS) (height SDS < -2, but normal GH response to provocation). The anatomy of the hypothalamic pituitary area was studied in patients with abnormal GH secretion using MRI scanning. Children with thalassaemia had significantly lower peak GH response to provocation by clonidine and glucagon (8.8 +/- 2.3 micrograms/l and 8.2 +/- 3.1 micrograms/l respectively) than did controls (17.6 +/- 2.7 micrograms/l and 15.7 +/- 3.7 micrograms/l respectively). They had significantly decreased circulating concentrations of IGF-I and IGFBP3 (68.5 +/- 19 ng/ml and 1.22 +/- 0.27 mg/l respectively) compared to controls (153 +/- 42 ng/ml and 2.16 +/- 0.37 mg/l respectively). Seven of the thalassaemic children had a GH peak response of < 7 micrograms/l after provocation. Those with a normal GH response after provocation also had significantly lower IGF-I and IGFBP3 concentrations than controls. Analysis of their spontaneous nocturnal GH secretion revealed lower mean (2.9 +/- 1.77 micrograms/l) and integrated (2.53 +/- 1.6 micrograms/l) concentrations compared to controls (4.9 +/- 0.29 micrograms/l and 5.6 +/- 0.52 micrograms/l respectively). Five of them had mean nocturnal GH concentration < 2 micrograms/l and four had maximum nocturnal peak below 10 micrograms/l. These data denoted defective spontaneous GH secretion in some of these patients. MRI studies revealed complete empty sella (n = 2), marked diminution of the pituitary size (n = 4), thinning of the pituitary stalk (n = 3) with its posterior displacement (n = 2), and evidence of iron deposition in the pituitary gland and midbrain (n = 7) in those patients with defective GH secretion (n = 9). Serum ferritin concentration was correlated significantly with the circulating IGF-I (r = -0.47, p < 0.01) and IGFBP3 (r = -0.43, p < 0.01) concentrations. These data prove a high prevalence of defective GH secretion in thalassaemic children associated with structural abnormality of their pituitary gland.
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PMID:Spontaneous and provoked growth hormone (GH) secretion and insulin-like growth factor I (IGF-I) concentration in patients with beta thalassaemia and delayed growth. 1066 1

Increased echogenicity of the pancreas, due to hemosiderosis, is a frequent laboratory finding in children and adolescents with beta-thalassemia. The aim of this study was to investigate whether increased echogenicity of the pancreas is associated with dysfunction. The ultrasonic image of the pancreas was examined in 34 children aged 12+/-3.8 years old and was compared to the endocrine and exocrine functioning of the gland. Oral glucose tolerance test (OGTT) was performed with simultaneous measurement of insulin and serum trypsin. Twenty-six of the 34 patients (76.5%) presented increased echogenicity, while 8 (23.5%) had a normal ultrasonic pancreatic image. 77% of the patients with increased echogenicity had abnormal OGTT, 46%, with subnormal or increased insulin values, and 32.5% manifested low levels of trypsin. Among the patients with normal ultrasound, 25% had abnormal OGTT and 37.5% abnormal insulin values. Statistical analysis with Student's t-test revealed that patients with increased echogenicity had significantly higher glucose values on OGTT at 60: 7.6 +/- 1.8 mmol/l (137.3 +/- 33.7 mg/dl) as compared to the patients with normal ultrasound: 6.1 +/- 1.2 mmol/l (110.75 +/- 21.72 mg/dl) (p<0.05). Insulin values were significantly affected at 30, 60, and 90 min: 570+/-301, 332+/-156, 294+/-158 pmol/l (79.54 +/- 42, 46.4 +/- 21.8, 41.04 +/- 22 mU/l) respectively in patients with increased echogenicity in comparison to those with normal ultrasonographic image of the gland: 301 +/- 170, 192 +/- 52, 135 +/- 63 pmol/l (42 +/- 23.7, 26.85 +/- 7.36, 18.9 +/- 8.8 mU/l) (p<0.05). No statistical significance was observed between the two groups regarding trypsin levels, even though abnormal values were observed in more children with increased echogenicity than in patients with a normal ultrasound. The above findings confirm that increased echogenicity of the pancreas is associated with disturbance of its function. This simple imaging method could be used as a rough early index of detection of an increased risk for developing diabetes mellitus in patients with beta-thalassemia.
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PMID:Ultrasonography of the pancreas, as a function index, in children with beta-thalassemia. 1071 56

Bone disease is an important cause of morbidity in older patients with beta-thalassaemia major and intermedia. We studied 27 women and 23 men with beta-thalassaemia major (37) and intermedia (13) whose mean age was 32.3 +/- 9.7 years. Bone mineral density (BMD) of the lumbar spine, femoral neck and distal radius was determined by dual-energy X-ray absorbiometry (DXA). The longitudinal change in BMD over a mean of 5.6 years was determined in 19 patients. Serum 25-hydroxyvitamin D, insulin growth factor-1 (IGF-1), bone formation markers bone-alkaline phosphatase, osteocalcin and the resorption marker urinary N-telopeptide cross-linked type 1 collagen (NTx) were determined. The BsmI vitamin D receptor (VDR) gene polymorphism was analysed. Reduced BMD (Z-score < -2) was present in 89%, 62% and 73% of patients in the spine, hip and radius respectively. Vitamin D deficiency was found in 62%, decreased IGF-1 in 72% and increased urinary NTx in 84% of patients. Serum IGF-1 correlated with spine and hip BMD (r = 0.4, r = 0.39, P < 0.01 respectively), and NTx correlated with the hip BMD Z-score (r = 0.35 P < 0.05). The mean annual percentage change in spine BMD was -1.36%. Patients with the VDR BB genotype had lower spine BMD than patients with the bb genotype. In conclusion, bone loss continues in adult thalassaemia patients and is associated with increased bone resorption and decreased IGF-1. The BsmI VDR gene polymorphism is associated with osteopenia in thalassaemia.
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PMID:Bone mineral metabolism in adults with beta-thalassaemia major and intermedia. 1112 54

Erythrocytes from diabetic patients exhibit impaired viscoelastic properties when estimated by various methods. We determined erythrocyte filterability through 5-microm pores, in 51 patients with non-insulin-dependent diabetes mellitus, 18 healthy controls, 15 patients with homozygous beta-thalassemia and 15 with beta-thalassemia traits. The filtration measurements were made with a Hemorheometer, which uses the "initial flow rate" principle. To determine the Index of Rigidity (IR) of the red blood cells, we measured the passage time of white blood cell-free erythrocyte suspensions, 8% per volume, through the filter. Diabetic patients had significantly increased IR in comparison to healthy controls and to patients with beta-thalassemia trait, but not at the level found in patients with homozygous beta-thalassemia. In diabetic patients, a strong correlation between IR and the percentage of glycosylated haemoglobin was found (r=0.737, P < 0.0001), and a weaker one with serum unconjugated bilirubin (r=0.363, P=0.0097) and serum total lipids (r=0.321, P=0.0286). Patients with severe retinopathy also had significantly increased IR, in comparison to those with or without mild retinopathy. Anaemic diabetic patients, especially those with the anaemia of chronic disease, also had significantly increased IR in comparison to non-anaemic diabetics. No correlation between IR, MCV, MCH, MCHC, RDW, RBC morphology, serum LDH or the presence of erythrocyte inclusions after incubation with nitrous sodium solution was found. Our findings suggest that glycosylation of skeletal proteins probably contributes significantly to the increased membrane rigidity of diabetic erythrocytes.
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PMID:Impairment of erythrocyte viscoelasticity is correlated with levels of glycosylated haemoglobin in diabetic patients. 1148 49

Vitamin E administration prevented DEHP induced deleterious effects like (i) degenerative changes in the brain and thyroid, (ii) decrease in the activity of neuronal membrane Na+ - K+ ATPase, (iii) decrease in the concentration of insulin, cortisol and TSH, and (iv) the increase in T3 and T4 in female Albino rats. The results suggest use of vitamin E to prevent harmful effects of repeated transfusion of DEHP containing blood as in thalassemia patient. The possibility of using vitamin E to prevent the harmful effects of repeated transfusion of DEHP containing blood, as in thalassemia patients, is discussed.
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PMID:Vitamin E prevents deleterious effects of di (2-ethyl hexyl) phthalate, a plasticizer used in PVC blood storage bags. 1546 79

This was the sixth in a series of symposia that began in Beijing, China in 1986. Approximately 100 chemists, environmental and biomedical scientists from 25 countries attended the meeting and presented some 80 papers on topics ranging from cancer chemotherapy to the production of paper. About half the papers presented could be broadly described as having medical implications, and of these, approximately half related directly to the use of platinum and the potential uses of other metals, such as palladium and the lanthanides, as anticancer agents. Many of these papers provided valuable insights into mechanisms of action and offered pointers for future research, but only rarely did they point to potential new drugs that might find early exploitation in clinical medicine. Two of the more exciting clinical developments were the introduction of the insulin-mimetic bis(maltolato)oxovanadium(IV) (KP-102; Kinetek Pharmaceuticals Inc/University of British Columbia) into clinical trials in the UK for the treatment of Type II diabetes, and the increasing importance of the orally active agent 3-hydroxy-pyridin-4-one-deferiprone (Apotex Inc/Cipla Ltd), in the treatment of iron overload in thalassemia.
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PMID:Royal Society of Chemistry--sixth international symposium on applied bioinorganic chemistry. 1596 42

Although numerous studies are available in the literature on endocrine complications in thalassaemia, little is known about this subject in developing countries. Therefore, an international multicenter study was conducted in a large series of children and adolescents with beta thalassaemia major in order to obtain more information on the prevalence of short stature and endocrine complications in different areas of the world and to elucidate the problems that must be dealt with in the future. A questionnaire was sent to 29 Centres treating a total of 3817 beta thalassaemia major patients. Thirty-six per cent of patients were over the age of 16 years. Short stature was present in 31.1% of males and 30.5% of females, and the prevalence of growth hormone deficiency was 7.9% in males and 8.8% in females. Lack of pubertal changes was the most common endocrine complication (40.5%) followed by hypoparathyroidism (6.9%), impaired glucose tolerance (6.5%), insulin-dependent diabetes mellitus (3.2%) and primary hypothyroidism (3.2%). The prevalence of endocrine complications differed among centres, particularly for growth hormone deficiency, hypoparathyroidism and hypothyroidism. Compliance to chelation therapy was poor in 51% of patients and serum liver enzymes were high in 65% of patients. Since several endocrine glands may be affected in patients with thalassaemia major, and their life expectancy is now much longer, it is important that physicians be aware of the endocrine abnormalities that may develop. Therefore, periodic evaluation of these problems should be carried out in thalassaemic patients with iron overload, particularly after the age of 11 years. In conclusion, since iron overload and liver damage seem to be the most important factors responsible for endocrine complications, adequate compliance to chelation therapy and rigid precautions against liver infections are imperative.
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PMID:Prevalence of endocrine complications and short stature in patients with thalassaemia major: a multicenter study by the Thalassaemia International Federation (TIF). 1646 5

We selected 92 subjects (46 females and 46 males), aged 10-15 years, from the Haematology and Endocrine Clinic of Shiraz University, Iran. Forty-six were beta thalassaemia patients (beta-Th) with short stature, 23 had idiopathic short stature (ISS) and 23 were healthy children with a standing height between the 10th and 95th percentile. Growth hormone (GH) secretion was normal in 23 beta-Th patients and reduced in the remaining 23 patients. A low insulin growth factor I (IGF-I) was found in 73.9% of beta-Th patients with GH deficiency, 56.5% of beta-Th patients with normal GH secretion to stimulation test and 8.7% of children with ISS. The reduced IGF-I concentration in beta-Th patients with normal GH secretion may be explained by partial insensitivity to GH (GHIS), neurosecretory dysfunction, low bioactive GH or increased proportion of circulating, non-22-kDa GH isoform. The possibility of GHIS in beta-Th patients with short stature indicates that higher doses of rechGH may be required to obtain an improvement in growth velocity in beta-Th patients.
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PMID:Reduced insulin growth factor I concentrations in iron-overloaded beta thalassaemic patients with normal growth hormone secretion and liver function. 1646 6

The pathogenesis of diabetes in thalassaemia is complex and multifactorial. Understanding the sequence of abnormalities in the progression from normal glucose tolerance to impaired glucose tolerance may help in the formulation of ways to intervene in this process. In our study, we assessed the effects of acarbose, an alpha-glucosidase inhibitor, in five young adult thalassaemic patients with hyperinsulinism and normal oral glucose tolerance test (OGTT). A decrease of fasting insulin levels, insulin peak and area under the curve (AUC) after OGTT, were observed in thalassaemic patients receiving acarbose therapy. These values remained unchanged in an untreated group of eight thalassaemic patients. We believe that acarbose may have a potential role in the treatment of abnormalities of glucose homeostasis and insulin release.
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PMID:Effects of acarbose in beta-thalassaemia major patients with normal glucose tolerance and hyperinsulinism. 1646 10

Recent advances in molecular genetics have led to a better understanding of hereditary iron overload syndromes, of which the most frequent are recessive HFE-hemochromatosis and, to a much lesser extent, dominant ferroportin disease. Acquired iron overload syndromes can be related to metabolic syndrome (insulin resistance syndrome), end-stage cirrhosis, or hematological disorders such as thalassemia and refractory anaemia.
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PMID:[Human hepatic iron overload syndromes]. 1673 93


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