Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pheochromocytoma is mainly characterized by a great deal of variability in its biological activity and in its clinical manifestations. This special feature has always to be taken into account in any diagnostic procedure. The tumor is generally suspected on clinical ground for the presence of paroxysmal hypertension but this sign is largely aspecific and often absent. The diagnosis of pheochromocytoma has to be based on laboratory tests demonstrating an excess and/or a disregulation in catecholamine (CA) secretion. CA or CA metabolites can be measured in urine or blood. Whatever the sample measured, it is important to correlate its result with the clinical picture found during its collection. Basal plasma CA concentrations are often raised also during periods of normotension but their accuracy is the highest in samples drawn during a hypertensive crisis. When basal measurements are insufficient for a final diagnosis, inhibitory (clonidine) or stimulatory (glucagon) tests can be performed. Clonidine test is recommended in patients showing slight increases in basal plasma CA. Glucagon stimulation test should be performed only in normotensive patients with an incidental adrenal mass, patients with sporadic hypertensive crises or members of families affected by MEN II. Localization procedures are mainly based on CT (or MRI) and on scintigraphy with I131-MIBG. CT possesses high sensitivity (about 96%) while I131-MIBG scintigraphy possesses a very high specificity (about 97%). Therefore, both the procedures should be performed before surgery. Rarely, it is also necessary to perform catheterization of the venous tree and plasma sampling for CA measurement to localize the tumor through the discovery of a secretory gradient.
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PMID:[Diagnostic problems in pheochromocytoma]. 765 Dec 83

We assessed the usefulness of endorectal surface coil MRI (ERSC-MRI) for staging diagnosis of prostate cancer to compare preoperative ERSC-MRI findings with pathological staging in patients performed radical prostatectomy. MR imaging was performed on a 1.5 T MR system with an endorectal surface coil designed for imaging the prostate. At the time the coil was inserted, 1.0 mg of glucagon was injected in tramuscularly. T1-weighted MR images were obtained in the axial plane, and T2-weighted, spin echo MR images were obtained in the sagittal, coronal, and axial planes for each patient. The capsular penetration of prostatic cancer was defined according to the six diagnostic criteria by Outwater et al.: (1) a bulge formation of the low-signal-intensity area beyond the prostatic capsule, (2) low-signal-intensity stranding in the periprostatic tissue, (3) retraction of the prostatic capsule besides the low-signal-intensity area, (4) elongation of the low-signal-intensity area in the prostatic capsule, (5) thickening of prostatic capsule. (6) extracapsular tumor. The sensitivity, specificity and accuracy of ERSC-MRI for capsular penetration of the prostatic cancer were 95.5%, 40.0%, and 85.2%, respectively. These results indicate that ERSC-MRI is useful for staging diagnosis of prostatic cancer.
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PMID:[Assessment of local staging of prostate cancer by endorectal surface coil]. 975 May 5

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

Exendin-4 is a 39 amino acid peptide produced in the salivary gland of the Gila monster lizard. It has a 53% amino acid homology to the incretin hormone glucagon-like peptide-1 (GLP-1). Exendin-4 induces insulin release through activation of the GLP- 1 receptor but is a much more potent insulinotropic agent than GLP-1. Of critical importance for its potential use as a treatment for diabetes is its much longer biological effect in vivo. Previous studies involving once daily administration of exendin-4 over 13 weeks to db/db mice demonstrated that it lowers hemoglobin A1c (HbA1c), a marker of mean blood glucose levels. Food consumption in the treated animals dropped over the first 4 days and then increased to a level comparable with that of the untreated animals. In this study, we initially examined the effect of once daily injections (over 14 days) on the food consumption of Zucker fatty rats. We observed an immediate reduction in food intake which then leveled off(after 5 days) to match that of the untreated animals. Subsequently we injected the same animals twice daily (treatment period of 56 days in total) and observed a sustained reduction in food intake and weight-gain. This was matched by a reduction in the critical parameters of HbA1c, fasting blood glucose and plasma insulin. MRI imaging of the abdominal regions of the animals showed that initially only the amount of fat deposited in the sc region was reduced after 4 weeks exendin-4 treatment. At the 8-week time point there was a corresponding decrease in the amount of visceral fat deposition. The combination of appetite reduction, decreased fat deposition and an improvement in the parameters associated with glucose intolerance makes a case for the use of exendin-4 as a treatment for diabetes.
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PMID:Exendin-4 decelerates food intake, weight gain, and fat deposition in Zucker rats. 1083 Feb 74

Seventeen patients with Cushing's disease (CD) were treated from 1978 to 2000. There were 11 males and 6 females aged 6.8-18.8 years (mean age 13.0 +/- 5.9 years). Presenting features were: weight gain (100%); growth failure (71%); hirsutism (53%); striae (53%); hypertension (47%). Mean age of patients with striae was 15.2 +/- 2.3 years, without striae 10.3 +/- 3.3 years. Median height SDS was -1.81 (range -0.28 to -4.17), 53% having height SDS < -1.8. The height velocity in 6 subjects was subnormal (0.9-3.8 cm/year). Median BMI SDS was 2.29 (range 1.72-5.06). Cushing's disease was confirmed by detectable serum ACTH, median 28 ng/l (range 12-99, NR <10-50) (n = 15); loss of cortisol circadian rhythm values at midnight ranging from 216 to 1,080 nmol/l (NR <50) (n = 15); lack of cortisol suppression (NV < 50 nmol/l) during low-dose dexamethasone suppression test (LDDST) (0.5 mg 6-hourly x 8) (n = 14); and >50% suppression of cortisol compared with the basal value during high-dose dexamethasone suppression test (HDDST) (2 mg 6-hourly x 8) (n = 14). A CRH test (1 microg/kg i.v.) showed an increase of cortisol from 12 to 217% (median 73.5%) (n = 16). Pituitary imaging (CT/MRI) showed an image consistent with microadenoma in 6/17 patients, but there was concordance between pituitary imaging and surgical findings in 1/11 patients (9%). Inferior petrosal sinus sampling (IPSS) for ACTH after CRH was performed in 11 subjects (age 10.7-18.8 years). Central to peripheral ACTH ratios were >2 (2.5-157.2) in 10/11 patients. The inter-petrosal sinus ACTH gradient was >1.4 in 10 patients (2.1-20.8), indicating lateralization of ACTH secretion. In 10 patients (91%), the side of the tumour on IPSS was predictive of findings at surgery. Therapy consisted of transsphenoidal microadenomectomy (TSS) in 16 patients and bilateral adrenalectomy (1978) in 1. Following TSS alone, 7 patients were cured (cortisol <50 nmol/l) and 2 were in remission (cortisol <300 nmol/l), i.e. 56%. Seven had persisting hypercortisolaemia and underwent pituitary irradiation (4,500 cGy). Therapeutic outcome for a median of 8 years (0.5-24 years) resulted in cure of CD in 14/17 patients (82%) and remission in 1. Linear growth after TSS +/- pituitary irradiation in 10 subjects showed no short-term catch-up growth, with peak growth hormone (GH) 0.5-20.9 mU/l to insulin tolerance test (ITT)/glucagon. Eight patients were treated with human growth hormone (hGH) (14 U/m(2)/week) combined in 3 with GnRH analogue. The mean final (n = 6) or latest (n = 4) height SDS was -1.36. The difference between final/latest height SDS and target height SDS was 0.93 +/- 1.13, i.e. less (p = 0.005) than the difference between height SDS and target height SDS at presentation, i.e. 1.72 +/- 1.26, indicating long-term catch-up growth.
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PMID:Cushing's disease in childhood: presentation, investigation, treatment and long-term outcome. 1140 58

Our objective was to determine the influence of patient-, study design-, and imaging protocol characteristics on staging performance of MR imaging in prostate cancer. In an electronic literature search and review of bibliographies (January 1984 to May 2000) the articles selected included data on sensitivity and specificity for local staging. Subgroup analyses examined the influence of age, prostate specific antigen, tumor grade, hormonal pre-treatment, stage distribution, publication year, department of origin, verification bias, time between biopsy and MR imaging; consensus reading, study design, consecutive patients, sample size, histology preparation, imaging planes, fast spin echo, fat suppression, endorectal coil, field strength, resolution, glucagon, contrast agents, MR spectroscopy, and dynamic contrast-enhanced MRI. Seventy-one articles and five abstracts were included, yielding 146 studies. Missing values were highly prevalent for patient characteristics and study design. Publication year, sample size, histologic gold standard, number of imaging planes, turbo spin echo, endorectal coil, and contrast agents influenced staging performance ( p=0.05). Due to poor reporting it was not possible to fully explain the heterogeneity of performance presented in the literature. Our results suggest that turbo spin echo, endorectal coil, and multiple imaging planes improve staging performance. Studies with small sample sizes may result in higher staging performance.
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PMID:Local staging of prostate cancer using magnetic resonance imaging: a meta-analysis. 1219 84

Pheochromocytomas (pheo) cause the most dramatic, life-threatening crises in all of endocrinology. A proper screening for pheo must be performed in any patient who has: 1) episodic headaches, tachycardia, and diaphoresis; 2) family history of pheo or multiple endocrine neoplasia; 3) incidental suprarenal mass; 4) paroxysms of tachyarrhythmias or hypertension; 5) adverse cardiovascular responses to anesthetic agents, histamine, phenothiazine, tricyclic antidepressants, etc); and 6) spells occurring during exercise, straining, etc. The key to diagnosing pheo is to suspect it, then to confirm it. Early recognition of its presence is critical to avoiding significant morbidity and mortality. Once suspected, the diagnosis can be confirmed with biochemical testing in virtually all patients. The combination of resting plasma catecholamines > or =2000 pg/mL and urinary metanephrines > or =1.8 mg/24 h has a diagnostic accuracy of 98% in both sporadic and hereditary pheos. When available, measurement of plasma free metanephrines should be performed especially in hereditary pheos. Provocative (glucagon) and suppression tests (clonidine) may be necessary when baseline measurements are inconclusive. CT and MRI are equally sensitive for localization (98% and 100%, respectively), but have lower specificities (70% and 67%). MIBG is 100% specific, but less sensitive (78%). The availability of various medical (selective alpha-1- and beta-adrenergic receptor antagonists, calcium channel blockers) and surgical modalities have made successful management more promising than ever before.
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PMID:Pheochromocytoma: current perspectives in the pathogenesis, diagnosis, and management. 1576 46

Detection of glycogen in vivo would have utility in the study of normal physiology and many disorders. Presently, the only magnetic resonance (MR) method available to study glycogen metabolism in vivo is (13)C MR spectroscopy, but this technology is not routinely available on standard clinical scanners. Here, we show that glycogen can be detected indirectly through the water signal by using selective radio frequency (RF) saturation of the hydroxyl protons in the 0.5- to 1.5-ppm frequency range downfield from water. The resulting saturated spins are rapidly transferred to water protons via chemical exchange, leading to partial saturation of the water signal, a process now known as chemical exchange saturation transfer. This effect is demonstrated in glycogen phantoms at magnetic field strengths of 4.7 and 9.4 T, showing improved detection at higher field in adherence with MR exchange theory. Difference images obtained during RF irradiation at 1.0 ppm upfield and downfield of the water signal showed that glycogen metabolism could be followed in isolated, perfused mouse livers at 4.7 T before and after administration of glucagon. Glycogen breakdown was confirmed by measuring effluent glucose and, in separate experiments, by (13)C NMR spectroscopy. This approach opens the way to image the distribution of tissue glycogen in vivo and to monitor its metabolism rapidly and noninvasively with MRI.
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PMID:MRI detection of glycogen in vivo by using chemical exchange saturation transfer imaging (glycoCEST). 1736 May 29

We describe a Japanese brother and sister with Martsolf syndrome. They had short stature, severe mental retardation, cataract, hypogonadism, craniofacial dysmorphism, and bone and joint symptoms including scoliosis, lax finger joints, and talipes valgus. Previously undescribed findings included proximal femoral epiphyseal dysplasia reminiscent of Legg-Calve-Perthes disease in both patients, and Klippel-Feil malformation and osteopathia striata in one patient. Brain MRI showed mild frontal and temporal lobe atrophy, and mild ventricular enlargement. Severe GH deficiency was demonstrated after insulin tolerance and glucagon/propranolol tolerance tests. No responses to serum LH and FSH after a gonadotropin-releasing hormone (GnRH) test suggested secondary hypogonadism, that is, hypogonadotropic hypogonadism, due to hypothalamus-pituitary axis insufficiency in both patients.
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PMID:Martsolf syndrome in Japanese siblings. 1739 1

A 16-year-old boy with transfusion-dependent thalassemia major presented with tetany, numbness, bone pain, short stature and pubertal delay. His height SDS score=-2.6, BMI=22.4, spleen was palpable 5 cm and liver 7 cm below the costal margins. The cardio-vascular examination was normal. Laboratory investigations showed a hemoglobin level (8 g/dL), hypocalcemia, hyperphosphatemia and elevated alkaline phosphatase (ALP) with serum 25-OH D below 3 ng/ml and a normal magnesium level. Serum parathyroid hormone (PTH) level was lower (21 pg/mL; normal 16-70 pg/mL) than expected for the degree of hypocalcemia. Serum ferritin concentration was 4442 ug/L, insulin-like growth factor I (IGF-I) was 31 microg/L (normal 122- 286 microg/L), free T4 was 13.1 microg/dL, TSH 1.2 mIU/ml. These results revealed a combined vitamin D-parathyroid defect. Peak growth hormone (GH) responses to clonidine and glucagon tests were 7.6 ng/ml and 6.2 ng/ml, respectively. Serum LH and FSH concentrations were below 0.5 U/L and testosterone was below 10 ng/dl. Radiographs revealed osteopenia of the phalanges and long bones and DXA scanning revealed low BMD Z-score of the femoral neck and 4th and 5th lumbar spines. MRI showed evidence of hemosiderin deposition in the pituitary. The patient was started on oral daily calcium carbonate (1500 mg elemental calcium) and vitamin D2 (calciferol) 25,000 IU/day and intensive iron chelation therapy. A low dose of IM testosterone enanthate (1 mg/kg/month) was injected for 6 months. Follow-up after 4, 8 and 12 months revealed normal Ca, PO4, ALP, and 25-OH D concentrations and disappearance of spasms and numbness and increased growth velocity. In conclusion, investigating calcium homeostasis at regular intervals and early management of any abnormality can preclude the occurrence of complications.
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PMID:An adolescent boy with thalassemia major presenting with bone pain, numbness, tetanic contractions and growth and pubertal delay: panhypopituitarism and combined vitamin D and parathyroid defects. 1933 71


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