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2. Deconjugated urinary metanephrine, normetanephrine and 3-methoxytyramine in laboratory diagnosis of pheochromocytoma and paraganglioma
- Creator:
- Radovan Bílek, Tomáš Zelinka, Petr Vlček, Jaroslava Dušková, David Michalský, Novák, K., Jiří Bešťák, and Jiří Widimský
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- Type:
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, moč, chromatografie, feochromocytomy, paragangliomy, urine, chromatography, pheochromocytoms, paraganglioms, deconjugated metanephrine, deconjugated normetanephrine, deconjugated 3-methoxytyramine, electrochemical detection, 14, and 612
- Language:
- English
- Description:
- This work discusses the clinical performance of deconjugated metanephrine (MN), normetanephrine (NMN) and 3-methoxytyramine (3MT) determined in the basal first morning urine using a chromatographic method with electrochemical detection for the clinical diagnosis of pheochromocytoma (PHEO) and paraganglioma (PGL). Urine samples were collected from 44 patients (36 with PHEO, 8 with PGL) aged 54+/-17 (20-78) years (22 females, 22 males). A sampling of biological materials was performed preoperatively and about one week, six months and one year after adrenal gland surgery. The control group consisted of 34 PHEO/PGL patients more than 4 months after adrenal gland surgery. All subjects in the control group were without a diagnosis of PHEO or PGL. Clinical sensitivity was 55 % for MN, 64 % for NMN, 80 % for combination of both MN and NMN, and only 23 % for 3TM. Clinical specificity calculated from the control group was 93 % for MN, 95 % for NMN, 95 % for the combination MN and NMN, and 97 % for 3TM. Cut-off values for deconjugated metanephrines in the basal urine were 310 (MN), 690 (NMN) and 250 μg/l (3MT). Chromatographic determination of deconjugated urinary metanephrines, which is simple without the necessity of special laboratory material, can serve for the screening of PHEO or PGL patients. Urine NMN and 3MT exerts an association to malignity, and all markers are associated with tumor mass. However, the principal laboratory diagnosis of PHEO or PGL must be based on plasma-free metanephrines and plasma chromogranin A with better performance in the laboratory diagnosis of PHEO or PGL., R. Bílek, T. Zelinka, P. Vlček, J. Dušková, D. Michalský, K. novák, J. Bešťák, J. Widimský Jr., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Diminished circadian blood pressure rhythm in patients with asymptomatic normotensive pheochromocytoma
- Creator:
- Tomáš Zelinka, Jiří Widimský, and Weisserová, J.
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, feochromocytomy, pheochromocytoms, pheochromocytoma, circadian blood pressure rhythm, 14, and 612
- Language:
- English
- Description:
- In our study, the circadian blood pressure (BP) rhythm was studied in subjects with asymptomatic and normotensive pheochromocytoma. We have therefore performed 24-hour BP monitoring not only in 6 subjects with asymptomatic pheochromocytoma, but also in 33 patients with symptomatic pheochromocytoma and in 10 normotensive subjects, who served as a control group. Circadian BP rhythm was expressed by assessing a relative night-time BP decline. We found a similar BP rhythm, catecholamine excretion and tumor size in subjects with both forms of pheochromocytoma. Subjects with asymptomatic pheochromocytoma had a significantly lower night-time systolic BP decline (P=0.01) and diastolic BP decline (P=0.006) than normotensive controls. We conclude that the attenuated night-time BP decline in normotensive and asymptomatic subjects with pheochromocytoma might be a possible sign of partial desensitization of the cardiovascular system to catecholamines., T. Zelinka, J. Widimský, J. Weisserová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Does the treatment of primary hyperaldosteronism influence glucose tolerance?
- Creator:
- Branislav Štrauch, Jiří Widimský, Gustav Šindelka, and Jan Škrha
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, krevní tlak, blood pressure, primary hyperaldosteronism, impaired glucose tolerance, 14, and 612
- Language:
- English
- Description:
- Primary hyperaldosteronism (PH) is frequently considered to be a secondary form of diabetes mellitus (DM). In our previous study we attempted to evaluate the prevalence of DM among patients with PH compared to control subjects with essential hypertension (EH). We have noted a relatively high prevalence of DM and impaired glucose tolerance in PH, but the differences between the PH and EH groups did not reach statistical significance. We performed this study to assess whether the effective treatment of PH (surgical and conservative) would improve the glucose tolerance. We have studied 24 patients with PH of the following two subtypes: aldosterone-producing adenoma (APA) treated with adrenalectomy and idiopathic hyperaldosteronism (IHA) treated with spironolactone. No significant changes of glucose levels were found in the 60th and 120th min of the oral glucose tolerance test (OGTT) in the APA group. On the other hand, fasting glucose levels were decreased significantly after adrenalectomy. Plasma glucose levels were significantly increased in the 60th min, but no differences were found in fasting values and in the 120th min in the IHA group. There was a significantly higher incidence of impaired glucose tolerance (36 % before, 45 % after treatment) and DM (9 %, 18 %) in the IHA group compared to the APA group (8 %, 32 %; DM 0 %, 0 %). In conclusion, the treatment of PH does not improve glucose tolerance. Mild worsening of glucose tolerance after treatment could be explained by an increase of the body mass index. These data, in accordance with our previous study, do not support the idea that PH is a secondary form of diabetes mellitus., B. Štrauch, J. Widimsky Jr., G. Šindelka, J. Škrha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Have main types of primary aldosteronism different phenotype?
- Creator:
- Z. Šomlóová, Indra, T., Jan Rosa, Ondřej Petrák, Branislav Štrauch, Tomáš Zelinka, Robert Holaj, and Jiří Widimský
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, primary aldosteronism, aldosterone producing adenoma, idiopathic hyperaldosteronism, pulse wave velocity, metabolic profile, 14, and 612
- Language:
- English
- Description:
- Primary aldosteronism (PA) is the most common cause of endocrine hypertension with a high frequency of cardiovascular complications. We found in our previous study higher occurrence of metabolic disturbances in patients with idiopathic hyperaldosteronism (IHA) compared to subjects with aldosterone-producing adenoma (APA). The aim of our present study is to evaluate potential differences in the frequency of endorgan damage (arterial stiffness and microalbuminuria) between two main types of PA. The diagnosis of the particular form of PA was based on adrenal venous sampling and/or histopathological examination. We analyzed clinical and laboratory data from 72 patients with PA (36 with IHA, 36 with APA). The arterial stiffness was expressed as the carotid-femoral pulse wave velocity (PWV) and the renal damage as urinary albumin excretion levels (UAE). Patients with IHA had significantly (p<0.03) higher prevalence of metabolic syndrome (17 % in APA, 35 % in IHA), higher triglycerides (1.37±0.71 mmol/l in APA, 1.85±0.87 mmol/l in IHA), lower HDL cholesterol (1.25±0.28 mmol/l in APA, 1.06±0.25 mmol/l in IHA), higher PWV (7.91±1.61 m/s in APA, 8.99±1.77 m/s in IHA) and higher UAE (12.93±2.21 mg/l in APA, 28.09±6.66 mg/l in IHA). It seems that patients with IHA may have a slightly different phenotype compared to APA., Z. Šomlóová ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. HIF signaling pathway in pheochromocytoma and other neuroendocrine tumors
- Creator:
- Jochmanová, I., Tomáš Zelinka, Jiří Widimský, and Karel Pacák
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, feochromocytomy, paragangliomy, terapie, pheochromocytoms, paraganglioms, therapy, pheochromocytoma, paraganglioma, hypoxia-inducible factor, oxygen sensing, 14, and 612
- Language:
- English
- Description:
- Hypoxia-inducible factors (HIFs) are transcription factors controlling energy, iron metabolism, erythropoiesis, and development. Dysregulation of these proteins contributes to tumorigenesis and cancer progression. Recent findings revealed the important role of HIFs in the pathogenesis of neuroendocrine tumors, especially pheoch romocytoma (PHEO) and paraganglioma (PGL). PHEOs and PGLs are catecholamine- producing tumors arising from sympathetic- or parasympathetic- derived chromaffin tissue. To date, eighte en PHEO/PGL susceptibility genes have been identified. Based on the main signaling pathways, PHEOs/PGLs have been divided into two clusters, pseudohypoxic cluster 1 and cluster 2, rich in kinase receptor signaling and protein translation pathways. Recent data suggest that both clusters are interconnected via the HIF signaling and its role in tumorigenesis is supported by newly described somatic and germline mutations in HIF2A gene in patients with PHEOs/PGLs associated with polycythemia, and in some of them also with somatostatinoma. Moreover, HIF α signaling has also been sh own to be upregulated in neuroendocrine tumors other than PHEO/PGL. Some of these tumors are components of hereditary tumor syndromes which can be associated with PHEO/PGL, but also in ileal carcinoids or melanoma. HIF signaling appears to be one of the crucial players in tumorigenesis, which could suggest new therapeutic approaches for treatment of neuroendocrine tumors., I. Jochmanová, T. Zelinka, J. Widimský Jr., K. Pacak., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Impaired insulin action in primary hyperaldosteronism
- Creator:
- Jiří Widimský, Gustav Šindelka, Tomáš Haas, Martin Prázný, Jiřina Hilgertová, and Jan Škrha
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, inzulin, inzulinová rezistence, insulin, insulin resistance, aldosterone, primary hyperaldosteronism, 14, and 612
- Language:
- English
- Description:
- The presence of insulin resistance is frequently found in essential hypertension. There are, however, only sparse data with respect to the potential presence of insulin resistance in patients with secondary hypertension. We have therefore undertaken a study to reveal the potential occurrence of insulin resistance in primary hyperaldosteronism (PH). The hyperinsulinemic euglycemic clamp technique together with the evaluation of insulin receptor characteristics were used to study insulin resistance in 12 patients with PH. The measured parameters were compared to normal values in control subjects. We have found a significantly lower glucose disposal rate (M, m mol/kg/min) (18.7± 6 vs. 29.3± 4), decreased tissue insulin sensitivity index (M/I, m mol/kg/min per mU/l x100) (23.7± 9.8 vs. 37.5± 11.6) and also lower metabolic clearance rate of glucose (MCRg, ml/kg/min) (3.8± 1.5 vs. 7.0± 1.1) in patients with primary hyperaldosteronism. The insulin receptor characteristics on erythrocytes did not differ in primary hyperaldosteronism as compared to control healthy subjects. We thus conclude that insulin resistance is also present in secondary forms of hypertension (primary hyperaldosteronism) which indicates the heterogeneity of impaired insulin action in patients with arterial hypertension., J. Widimský Jr., G. Šindelka, T. Haas, M. Prázný, J. Hilgertová, J. Škrha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Inflammatory markers in primary aldosteronism
- Creator:
- Z. Šomlóová, Ondřej Petrák, Jan Rosa, Branislav Štrauch, Indra, T., Tomáš Zelinka, Martin Haluzík, Vít Zikán, Robert Holaj, and Jiří Widimský
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- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, primary aldosteronism, PINP, 14, and 612
- Language:
- English
- Description:
- Primary aldosteronism (PA) is the most common cause of endocrine hypertension with a high frequency of cardiovascular complications. The unfavorable cardiometabolic profile may be due to aldosterone-mediated activation of inflammatory cells, circulatory cytokines and activation of collagen synthesis in the vessel wall. Aim of our study was to evaluate differences in the levels of hsCRP, IL-6, TNF-α and N-terminal propeptide of collagen I (PINP) in patients with PA and essential hypertension (EH) as a control group, and between the subtypes of PA (aldosterone producing adenoma - APA, idiopathic hyperaldosteronism - IHA). We studied 28 patients with PA (IHA - 10 patients, APA - 12 patients, 6 unclassified) and 28 matched patients with EH. There were no differences in the levels of inflammatory markers between the followed groups [EH vs. PA: TNF-α (5.09 [3.68-6.32] vs. 4.84 [3.62-6.50] pg/ml), IL-6 (0.94 [0.70-1.13] vs. 0.97 [0.71- 1.28] pg/ml), hsCRP (0.53 [0.25-1.54] vs. 0.37 [0.31-0.61] mg/l), leukocytes (6.35±1.42 vs. 5.97±1.29 109 l); APA vs. IHA: TNF-α (4.54 [3.62-7.03] vs. 5.19 [4.23-5.27] pg/ml), IL-6 (0.96 [0.63- 1.21] vs. 0.90 [0.65-1.06] pg/ml), hsCRP (0.34 [0.29-0.47] vs. 0.75 [0.36-1.11] mg/l), leukocytes (6.37±1.41 vs. 5.71±1.21 109 l)]. Significant differences in the levels of PINP between PA and EH group were observed (35.18 [28.46-41.16] vs. 45.21 [36.95-62.81] μg/l, p≤0.003). No differences in inflammatory markers were observed between the followed groups, we confirmed higher levels of PINP in patients with PA., Z. Šomlóová, O. Petrák, J. Rosa, B. Štrauch, T. Indra, T. Zelinka, M. Haluzík, V. Zikán, R. Holaj, J. Widimský Jr., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Lower physical fitness in patients with primary aldosteronism is linked to the severity of hypertension and kalemia
- Creator:
- Vladimír Tuka, Martin Matoulek, Tomáš Zelinka, Rosa, J., Ondřej Petrák, Mikeš, O., Zuzana Krátká, Branislav Štrauch, Robert Holaj, and Jiří Widimský
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tělesná kondice, physical fitness, primary hyperaldosteronism, exercise blood pressure, exercise stress test, 14, and 612
- Language:
- English
- Description:
- Hypokalemia as a typical feature of primary aldosteronism (PA) is associated with muscle weakness and could contribute to lower cardio pulmonary fitness. The aim of this study was to describe cardiopulmonary fitness and exercise blood pressure and their determinants during a symptom-limited exercise stress test in patients with PA. We performed a cross-sectional study of patients with confirmed PA who were included before adrenal vein sampling on whom a symptom-limited exercise stress test with expired gas analysis was performed. Patients were switched to the treatment with doxazosin and verapamil at least tw o weeks befor e the study. In 27 patients (17 male) the VO 2peak was 25.4± 6.0 ml/k g/min which corresponds to 80.8 ±18.9 % of Czech national norm. Linear regression analysis shows that VO 2peak de pends on doxazosin dose (DX) (p=0.001) and kal emia (p= 0.02): VO 2peak = 4.2 - 1.0 * DX + 7.6 * Ka lemia. Patients with higher doxazosin doses had a longer history of hypertension and had used more antihypertensives before examination, thus indicating that VO 2peak also depends on the severity of hypertension. In patients with PA, lower cardiopulmonary fitness depends inversely on the severity of hypertension and o n lower plasma potassium level., V. Tuka, M. Matoulek, T. Zelinka, J. Rosa, O. Petrák, O. Mikeš, Z. Krátká, B. Štrauch, R. Holaj, J. Widimský Jr., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Peripheral arterial stiffness in primary aldosteronism
- Creator:
- Jan Rosa, Z. Šomlóová, Ondřej Petrák, Branislav Štrauch, Indra, T., Šenitko, M., Tomáš Zelinka, Robert Holaj, and Jiří Widimský
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, peripheral arterial stiffness, primary aldosteronism, peripheral pulse wave velocity, 14, and 612
- Language:
- English
- Description:
- Aldosterone overproduction increases arterial wall stiffness by accumulation of different types of collagen fibres and growth factors. Our previous studies showed that central (aortic) arterial stiffness is increased in primary aldosteronism (PA) independently of concomitant hypertension and that these changes might be reversible after successful adrenalectomy. There is limited data available on the potential impact of mineralocorticoid overproduction on the deterioration of peripheral arterial stiffness. The current study was thus aimed at investigating the effect of aldosterone overproduction on peripheral arterial stiffness assessed by peripheral (femoralankle) pulse wave velocity (PWV) in PA patients compared with essential hypertension (EH) patients. Forty-nine patients with confirmed PA and 49 patients with EH were matched for age, blood pressure, body mass index, lipid profile, and fasting glucose. PWV was obtained using the Sphygmocor applanation tonometer. Both peripheral and central PWV were significantly higher in PA patients compared to EH patients, while clinical blood pressures were similar. Plasma aldosterone level was the main predictor of peripheral PWV in PA. Our data indicate aldosterone overproduction in PA does not preferentially affect central arterial system. Fibroproliferative effect of higher aldosterone levels lead to alteration of central-elastic as well as peripheral-muscular arteries with subsequent increase in its stiffness., J. Rosa ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public