| 51. |
- Cunningham, Janet L., et al.
(författare)
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Tachykinins in endocrine tumors and the carcinoid syndrome
- 2008
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Ingår i: European Journal of Endocrinology. - 0804-4643 .- 1479-683X. ; 159:3, s. 275-282
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Tidskriftsartikel (refereegranskat)abstract
- ObjectiveA new antibody, active against the common tachykinin (TK) C-terminal. was used to study TK expression in patients with endocrine tumors and a possible association between plasma-TK levels and symptoms of diarrhea and flush in patients with metastasizing ileocecal serotonin-producing carcinoid tumors (MSPCs).MethodTK, serotonin and chromogranin A (CgA) immunoreactivity (IR) was studied by immunohistochemistry in tissue samples from 33 midgut carcinoids and 72 other endocrine tumors. Circulating TK (P-TK) and urinary-5 hydroxyindoleacetic acid (U-5HIAA) concentrations were measured in 42 patients with MSPCs before treatment and related to symptoms in patients with the carcinoid syndrome. Circulating CgA concentrations were also measured in 39 out of the 42 patients.ResultsAll MSPCs displayed serotonin and strong TK expression. TK-IR was also seen in all serotonin-producing lung and appendix carcinoids. None of the other tumors examined contained TK-IR cells. Concentrations of P-TK, P-CgA, and U-5HIAA were elevated in patients experiencing daily episodes of either flush or diarrhea, when compared with patients experiencing occasional or none of these symptoms. In a Spearman partial rank test, the correlation of P-TK with daily diarrhea was independent of both U-5HIAA and CgA levels.ConclusionWe found that TK synthesis occurs in serotonin-IR tumors and that P-TK levels are significantly correlated with symptoms of flush and diarrhea in patients with MSPCs. This is. to our knowledge, the first report demonstrating an independent correlation of P-TKs with carcinoid diarrhea, a symptom that is customarily regarded as serotonin mediated. Further investigations may present opportunities for new therapeutic possibilities.
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| 52. |
- Dahlman, T, et al.
(författare)
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Integrins in thyroid tissue: upregulation of alpha2beta1 in anaplastic thyroid carcinoma
- 1998
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Ingår i: European journal of endocrinology. - : Oxford University Press (OUP). - 0804-4643 .- 1479-683X. ; 138:1, s. 104-112
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To evaluate the integrin pattern in the normal thyroid gland and in different pathological disorders including malignant tumors, because the aggressiveness of several malignant tumors correlates with alterations in the expression of one or more integrins. DESIGN: We examined the expression of integrins and E-cadherin immunohistochemically in a large and well-defined sample of normal and pathological human thyroid tissue. METHODS: Cryosections of 58 thyroid tissue specimens from normal tissue, thyrotoxicosis, nodular goiter, oxyphilic adenoma, follicular adenoma, follicular carcinoma, papillary carcinoma and anaplastic carcinoma, and three lymph node metastases were investigated immunohistochemically using monoclonal antibodies specifically recognizing the integrin beta1-, beta4-, alpha1-, alpha2-, alpha3-, alpha5- and alpha6-subunits, or E-cadherin. RESULTS: All thyroid epithelial cells expressed integrin beta1- and alpha3-subunits. Immunostaining of the beta4-subunit and the alpha6-subunits was found only in tumors. The staining pattern in the three lymph node metastases from papillary carcinomas did not differ from that in their primaries. Anaplastic carcinomas demonstrated neoexpression of the integrin alpha2-subunit. E-cadherin was detected in all tissues except anaplastic carcinomas. CONCLUSIONS: Neoexpression of alpha6beta4 was seen in most malignant tumors, whereas alpha2 was exclusively found in anaplastic carcinomas. In the latter, a loss of E-cadherin expression was also seen. These changes in cell adhesion molecule expression strongly suggest an association with the acquisition of proliferative and invasive properties.
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| 53. |
- Demelash, Abeba, 1962, et al.
(författare)
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Selenium has a protective role in caspase-3-dependent apoptosis induced by H2O2 in primary cultured pig thyrocytes.
- 2004
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Ingår i: European journal of endocrinology / European Federation of Endocrine Societies. - 0804-4643. ; 150:6, s. 841-9
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Hydrogen peroxide (H2O2), necessary for thyroid hormonogenesis, is produced at the apical surface of the thyroid follicular epithelium. Excess H2O2 is potentially cytotoxic and may contribute to the development of hypothyroidism, e.g. in severe selenium deficiency. Yet it is unclear how H2O2 contributes to thyroid cell death. DESIGN AND METHODS: H2O2-induced apoptosis and necrosis were studied in primary cultured pig thyroid cells. Glutathione peroxidase (GPx) activity was altered by culture in low serum with or without selenite substitution. Apoptosis was evaluated by spectrofluorometric measurement of caspase-3-specific substrate cleavage, and by analysis of DNA fragmentation by agarose gel electrophoresis. Necrosis was detected by 51Cr release from prelabeled cells. RESULTS: Exogenous H2O2 dose-dependently (100-400 micromol/l) activated caspase-3 within 3-12 h, and DNA degradation was observed after 24 h. The potency of H2O2 to induce apoptosis was low compared with that of staurosporine, a strong proapoptotic agent. H2O2-treated cells with reduced GPx activity showed increased caspase-3 activation. Incubation of serum-starved cells with selenite (10-100 nmol/l) normalized the GPx activity and reduced the activation of caspase-3 by H2O2. High H2O2 concentrations (400-800 micromol/l) were required to obtain necrosis. The H2O2-induced necrosis was exaggerated by both low GPx activity and catalase inhibition. CONCLUSIONS: Cytotoxic effects of H2O2 on thyroid cells include caspase-3-dependent apoptosis that occurs at H2O2 concentrations insufficient to induce necrosis. Selenium deficiency aggravates the apoptotic response, probably due to impaired capacity of GPx to degrade H2O2.
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| 54. |
- Dogra, Prerna, et al.
(författare)
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Rare benign adrenal lesions
- 2023
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Ingår i: European Journal of Endocrinology. - : Oxford University Press. - 0804-4643 .- 1479-683X. ; 188:4, s. 407-420
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Tidskriftsartikel (refereegranskat)abstract
- While most benign lesions of the adrenal glands represent either an adrenocortical adenoma or a myelolipoma, the advent and frequent use of high-resolution radiological investigations have led to relatively increased incidental discovery of rare adrenal lesions, specifically benign adrenal cysts, adrenal ganglioneuromas, adrenal schwannomas, adrenal hemorrhage, and adrenal calcifications. Radiological characteristics of the different rare benign adrenal lesions could vary from distinct to indeterminate. Though typically nonfunctional, these rare lesions require evaluation for adrenal hormone excess, as they may phenotypically appear similar to pheochromocytoma or adrenocortical carcinoma and could sometimes be associated with or conceal an underlying functional adrenal tumor. In this review, we discuss the various rare benign adrenal lesions, emphasizing a practical perspective.
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| 55. |
- Dutta, Ravi Kumar, et al.
(författare)
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A somatic mutation in CLCN2 identified in a sporadic aldosterone-producing adenoma
- 2019
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Ingår i: European Journal of Endocrinology. - : BIOSCIENTIFICA LTD. - 0804-4643 .- 1479-683X. ; 181:5, s. K37-K41
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To screen for CLCN2 mutations in apparently sporadic cases of aldosterone-producing adenomas (APAs). Description: Recently, CLCN2, encoding for the voltage-gated chloride channel protein 2 (CIC-2), was identified to be mutated in familial hyperaldosteronism II (FH II). So far, somatic mutations in CLCN2 have not been reported in sporadic cases of APAs. We screened 80 apparently sporadic APAs for mutations in CLCN2. One somatic mutation was identified at p.Gly24Asp in CLCN2. The male patient had a small adenoma in size but high aldosterone levels preoperatively. Postoperatively, the patient had normal aldosterone levels and was clinically cured. Conclusion: In this study, we identified a CLCN2 mutation in a sporadic APA comprising about 1% of all APAs investigated. This mutation was complementary to mutations in other susceptibility genes for sporadic APAs and may thus be a driving mutation in APA formation.
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| 56. |
- Dwight, T, et al.
(författare)
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Genetic analysis of lithium-associated parathyroid tumors
- 2002
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Ingår i: European journal of endocrinology. - : Oxford University Press (OUP). - 0804-4643 .- 1479-683X. ; 146:5, s. 619-627
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The aim of this study was to determine the primary genetic events that may underlie the formation of parathyroid tumors in patients with lithium-associated hyperparathyroidism (HPT). METHODS: Comparative genomic hybridization (CGH), loss of heterozygosity (LOH) and multiple endocrine neoplasia type 1 gene (MEN1) mutation analysis were used to analyze twelve parathyroid tumors from nine patients with lithium-associated HPT. For comparison, CGH was also carried out in a non-lithium-associated group of thirteen sporadic parathyroid tumors. RESULTS: A higher prevalence of multiglandular disease in the lithium-associated HPT patients compared with the idiopathic sporadic patients was observed (Fisher's exact test, P=0.02). CGH alterations were detected in four lithium-associated parathyroid tumors, involving loss at 1p, 11, 15q, 22q and gain of the X chromosome. In addition, one of these four cases exhibited LOH at 11q13 and was found to contain a novel somatic MEN1 mutation (c.1193insTAC). Although fewer lithium-associated parathyroid tumors were shown to contain genetic alterations compared with the sporadic parathyroid tumors, the changes detected were those frequently associated with both familial and sporadic parathyroid tumorigenesis. CONCLUSION: This is, to our knowledge, the first genetic analysis of parathyroid tumors in lithium-associated HPT patients. Our data indicated that the majority of lithium-associated parathyroid tumors do not contain gross chromosomal alterations and suggest that in most cases the tumorigenic pathway is independent of MEN1 and genes at 1p34.3-pter and 1q21-q32. It is possible that other discrete genetic alterations or epigenetic changes, not screened for in this study, could also be responsible for parathyroid tumorigenesis in lithium-associated HPT.
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| 57. |
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| 58. |
- Eendebak, Robert J A H, et al.
(författare)
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The androgen receptor gene CAG repeat in relation to 4-year changes in androgen-sensitive endpoints in community-dwelling older European men
- 2016
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Ingår i: European Journal of Endocrinology. - 0804-4643. ; 175:6, s. 583-593
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Tidskriftsartikel (refereegranskat)abstract
- Context: The androgen receptor (AR) gene exon 1 CAG repeat length has been proposed to be a determinant of between-individual variations in androgen action in target tissues, which might regulate phenotypic differences of human ageing. However, findings on its phenotypic effects are inconclusive. Objective: To assess whether the AR CAG repeat length is associated with longitudinal changes in endpoints that are influenced by testosterone (T) levels in middle-Aged and elderly European men. Design: Multinational European observational prospective cohort study. Participants: A total of 1887 men (mean ± s.d. age: 63 ± 11 years; median follow up: 4.3 years) from centres of eight European countries comprised the analysis sample after exclusion of those with diagnosed diseases of the hypothalamic-pituitary-testicular (HPT) axis. Main outcome measures: Longitudinal associations between the AR CAG repeat and changes in androgen-sensitive endpoints (ASEs) and medical conditions were assessed using regression analysis adjusting for age and centre. The AR CAG repeat length was treated as both a continuous and a categorical (6-20; 21-23; 24-39 repeats) predictor. Additional analysis investigated whether results were independent of baseline T or oestradiol (E2) levels. Results: The AR CAG repeat, when used as a continuous or a categorical predictor, was not associated with longitudinal changes in ASEs or medical conditions after adjustments. These results were independent of T and E2 levels.
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| 59. |
- Ekman, Bertil, et al.
(författare)
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A dose titration model for recombinant GH substitution aiming at normal plasma concentrations of IGF-I in hypopituitary adults
- 2002
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Ingår i: European Journal of Endocrinology. - : Oxford University Press (OUP). - 0804-4643 .- 1479-683X. ; 147:1, s. 49-57
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To evaluate a dose titration model for recombinant human GH substitution in adult patients with GH deficiency, aiming at normal plasma levels of IGF-I.DESIGN AND METHODS: Eighteen patients participated and a start dose of 0.17 mg GH/day was used except by two men who started with 0.33 mg/day. To demonstrate a clear GH effect the patients were first titrated, with steps of 0.17 mg GH/day every 6-8 weeks, to IGF-I levels in the upper range of age-adjusted reference values. The GH dose was then reduced 1 dose step and kept for a further 6 months. For comparison we investigated 17 healthy control subjects.RESULTS: Plasma IGF-I was increased after 2 weeks on the start dose and did not increase further for up to 8 weeks. Women had significantly lower GH sensitivity than men measured as net increment of IGF-I on the start dose of GH. GH sensitivity was not changed by age. The plasma IGF-I levels increased from 76.3+/-47.0 (s.d.) to 237+/-97 microg/l at the end of the study (P<0.001), and similar IGF-I levels were obtained in both sexes. The maintenance median GH dose was 0.33 mg/day in males and 0.83 mg/day in females (P=0.017). The GH dose correlated negatively with age in both sexes. Body weight, very low density triglycerides, lipoprotein(a) (Lp(a)), and fasting insulin increased, whereas insulin sensitivity index (QUICKI) decreased significantly. In comparison with the controls, the patients had lower fasting blood glucose, fasting insulin and Lp(a) levels at baseline, but these differences disappeared after GH substitution. The two groups had equal insulin sensitivity (QUICKI), but 2 h oral glucose tolerance test values of blood glucose and insulin were significantly higher in the patients at the end of the study.CONCLUSIONS: In conclusion our data suggest that the starting dose of GH substitution and the dose titration steps should be individualised according to GH sensitivity (gender) and the IGF-I level aimed for (age). The reduced insulin sensitivity induced by GH substitution could be viewed as a normalisation if compared with control subjects.
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| 60. |
- Ekman, Bertil, et al.
(författare)
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Circulating IGF-I concentrations are low and not correlated to glycaemic control in adults with type 1 diabetes
- 2000
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Ingår i: European Journal of Endocrinology. - : Oxford University Press (OUP). - 0804-4643 .- 1479-683X. ; 143:4, s. 505-510
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study plasma concentrations of insulin-like growth factor-I (IGF-I) in adults with type 1 diabetes (IDDM) in comparison with a reference population, and the influence of glycaemic control, dose of insulin, and sex on the concentration of circulating IGF-I in IDDM.DESIGN AND METHODS: Patients with type 1 diabetes were recruited consecutively from our outpatient diabetes unit. In all, 79 men and 55 women aged 20-60 years with a disease duration >/=6 years (range 6-51 years) took part in the study. A reference population of 80 men and 83 women aged 20-60 years was randomly obtained from the population registry. IGF-I was measured with radioimmunoassay after acid-ethanol extraction.RESULTS: Mean +/- s. d. values of IGF-I were lower in patients with diabetes (146+/-66 microg/l) than in controls (238+/-83 microg/l, P<0.001). Those with diabetes had lower IGF-I concentrations in all age groups and the differences were highly significant in all decades except in women aged 50-59 years. IGF-I was negatively correlated with age in patients and controls. No correlation was found between IGF-I and glycaemic control measured as haemoglobin A(1c) (HbA(1c)) in the patients. IGF-I was positively associated with the dose of insulin/kg body weight in male patients independently of age, HbA(1c) and body mass index (P<0.03), but not in female patients (P=0.14).CONCLUSIONS: Our data show that IGF-I concentrations are low in adult patients with type 1 diabetes with a disease duration >/=6 years, independently of glycaemic control. This suggests that subcutaneous insulin substitution is inadequate to normalize circulating IGF-I concentrations in patients without endogenous insulin secretion.
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