Analysis of PTEN mutation in non-familial pheochromocytoma.

PTEN, a tumor suppressor gene, is frequently mutated in a variety of human tumors. In mice, monoallelic inactivation of this gene predisposes animals to neoplasia of multiple organs. Interestingly, Pten heterozygous mice develop bilateral hyperplasia of the adrenal medulla.

Catecholamine excretion and circadian blood pressure profile in patients with pheochromocytoma.

Circadian blood pressure (BP) rhythm is often disturbed in patients with secondary forms of hypertension. The aim of the present article was to investigate changes in circadian BP profile parameters using two-step statistical approach by Fourier analysis in relation to day and night urinary catecholamine excretion in 35 patients with pheochromocytoma (mean age 42+/-19 years). Twenty-four-hour ambulatory BP measurements (ABPM) were obtained using the SpaceLabs 90,207 monitor.

The effects of genetic factors on selected indicators of the activity of the sympathoadrenal system and the renin-angiotensin-aldosterone system in twins.

Background: There are numerous data indicating a significant role of the sympathoadrenal system and the reninangiotensin- aldosterone system in the regulation of blood pressure and the pathogenesis of essential hypertension. However, the genetic background of essential hypertension remains unclear.

Aim: To determine the effects of genetic factors on selected indicators of the activity of the sympathoadrenal system and the renin-angiotensin-aldosterone system in twins.

Plasma neuropeptide Y immunoreactivity influences left ventricular mass in pheochromocytoma.

Unlabelled: Left ventricular hypertrophy (LVH) in patients with arterial hypertension is closely related to the levels of blood pressure (BP), catecholamines, angiotensin II and other mitogenic peptides. Pheochromocytoma (pheo) is a type of hypertension caused by excessive production of catecholamines. The aim of this study was to determinate if left ventricular hypertrophy in patients with pheochromocytoma is related to catecholamines and neuropeptide Y (NPY).

[Non-traditional atherosclerosis risk factors in patients with renal artery stenosis and hypertension].

The most investigated novel risk factors of atherosclerosis are: fibrinogen (Fb), homocysteine (Hcy), lipoprotein (a) (Lp(a)), plasminogen activator inhibitor (PAI-1), markers of inflammation and infectious factors. Atherosclerotic renal artery stenosis (RAS) is a manifestation of generalized atherosclerosis and often coexist with hypertension and renal failure. The aim of the study was to assess plasma concentration of Hcy, von Willebrand factor (VWF), (Lp(a), Fb, PAI-1, and assessment of ACE gene polymorphism in pts with RAS and hypertension.

Genetic influence on blood pressure and lipid parameters in a sample of Polish twins.

We studied 76 healthy monozygotic (MZ) and same-sex dizygotic (DZ) twin pairs (mean age 35 +/- 8 years, body mass index, BMI, 23.6 +/- 3.9 kg/m2) to determine genetic and environmental contributions to systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR) and serum lipids [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-chol), high-density lipoprotein cholesterol (HDL-chol) and triglycerides (TG)I.

Do catecholamines influence the level of plasma leptin in patients with phaeochromocytoma?

The relationship between plasma leptin and catecholamine concentrations during chronic and acute catecholamine excess is studied. Patients with phaeochromocytoma, divided according to gender, were examined under basal conditions (n = 18) and at selected time-points during surgical removal of the tumour (n = 12). Appropriate controls were used (n = 23) for the basal study.

Homocysteine, adrenergic activity and left ventricular mass in patients with essential hypertension.

Objective: Assessment of relationship between homocysteine (Hcy) and noradrenaline (NA), adrenaline (A) concentration and left ventricular mass index (LVMI) in patients with essential hypertension (EH).

Design And Methods: Samples obtained from 37 patients (14 female, 23 male) with mild EH (according to WHO criteria) (mean age 43.6 +/- 13.

Dopamine and dopa urinary excretion in patients with pheochromocytoma--diagnostic implications.

Pheochromocytoma, a potentially life-threatening disease, is a rare cause of hypertension. Most pheochromocytomas secrete excessive amounts of noradrenaline and adrenaline. It has been suggested by some authors that high circulating levels of dopamine and the catecholamine precursor dihydroxyphenylalanine (dopa) are more often associated with malignant rather than benign pheochromocytomas.

Do catecholamines influence the level of plasma leptin in patients with phaeochromocytoma?

The relationship between plasma leptin and catecholamine concentrations during chronic and acute catecholamine excess is studied. Patients with phaeochromocytoma, divided according to gender, were examined under basal conditions (n=18) and at selected time-points during surgical removal of the tumour (n=12). Appropriate controls were used (n=23) for the basal study.

Immunomorphological studies and cytometric DNA ploidy in diagnostics of pheochromocytoma.

The aim of the study was to define features indicating malignancy in pheochromocytoma through analysis of clinical data, immunomorphological and nuclear DNA ploidy patterns with flow cytometry. The studied group consisted of 33 patients with hypertension and adrenal gland tumor. In all patients 24 hr measurements of adrenaline, noradrenaline, dopamine and their metabolites were taken and the content of these substances in the tumor tissue was measured.

Incidence and clinical relevance of RET proto-oncogene germline mutations in pheochromocytoma patients.

Background: Autosomal dominant cancer syndrome--multiple endocrine neoplasia type 2 (MEN 2), may exist more often than expected in patients with pheochromocytoma. Germline mutations identified recently in MEN 2 can be revealed by genetic screening.

Objective: To evaluate the frequency of RET (rearranged during transfection) mutations in patients with pheochromocytoma.

Blood pressure, plasma NPY and catecholamines during physical exercise in relation to menstrual cycle, ovariectomy, and estrogen replacement.

Some evidences indicate that the female sex hormones protect against the development of cardiovascular diseases. Modulation of sympathetic activity may be one of the possibilities. We investigated the influence of treadmill stress on blood pressure (BP) and plasma neuropeptide Y (NPY), norepinephrine (NE) and epinephrine (E) concentrations in 11 normotensive, menstruating women in the follicular (HWf) and luteal (HWl) phases and in eight ovariectomized women, before (OVX) and after estrogen supplementation (OVXe).

Alterations in plasma neuropeptide Y immunoreactivity and catecholamine levels during surgical removal of pheochromocytoma.

Background: Neuropeptide Y, an abundant neurohormone present with catecholamines in the adrenal medulla, is a potent non-adrenergic vasoconstrictor and a vascular growth factor.

Objective: To determine the mechanism of the release from, and possible role of neuropeptide Y in, pheochromocytomas, compared with those of catecholamines.

Methods: Plasma and tumour levels of neuropeptide Y-immunoreactivity (by, radioimmunoassay) and of noradrenaline and adrenaline (by a radioenzymatic method) in 29 patients (19 women and 10 men, aged 22-68 years) were measured during surgical removal of the tumour, during alpha-adrenergic and beta-adrenergic blockade.

Hemorrheological indices, catecholamines, neuropeptide Y and serotonin in patients with essential hypertension.

Hemorrheological and humoral abnormalities and excessive platelet activity can predict the development of cardiovascular complications in patients with essential hypertension. A study was conducted to assess the influence of gender on these factors and the interrelations between changes in hemorrheology and the sympatho-adrenal system in 54 patients (18 women, 36 men) with essential hypertension (aged 39.6 +/- 9.

[Pheochromocytoma in a 81 year old woman treated with surgery--case report].

A case of pheochromocytoma in 81 year old woman hospitalized due to choledocholithiasis is reported. During premedication pronounced blood pressure elevation was observed. Operation was discontinued and diagnostic of pheochromocytoma was carried out.

[Evaluation of the usefulness for measuring catecholamines and their principle metabolites in the diagnosis of pheochromocytoma].

Objective of the study was assessment of the usefulness of determination of noradrenaline (NA) and adrenaline (A) in urine and blood as well as the total methoxycatecholamines (MNA +MA), vanillylmandelic acid (VMA), DOPA and dopamine (DA) urinary excretion in diagnosis of pheochromocytoma. The experience based on 155 patients with pheochromocytoma (105F, 50M, age 18-82 yrs) diagnosed in the Department of Hypertension and Angiology Academy of Medicine in Warsaw will be discussed. In all patients excluding 2 cases pheochromocytoma has been proven histopathologically.

[Pheochromocytoma with hemorrhagic necrosis and rupture with symptoms of acute abdomen and shock].

A case of a pheochromocytoma with haemorrhagic necrosis resulting in signs of acute abdomen with shock is reported. Diagnosis of a ruptured adrenal tumor was made by CT scanning. Elevated urine and plasma catecholamines as well as histological examination of the removed tumor confirmed the clinical suspicion of pheochromocytoma.

Circulating neuropeptide Y in humans: relation to changes in catecholamine levels and changes in hemodynamics.

Neuropeptide-Y (NPY) is a sympathetic cotransmitter, which causes vasoconstriction, decreases coronary blood flow and decreases cardiac output. Circulating immunoreactive NPY (ir-NPY) levels increase with exercise, in patients admitted to the coronary care unit, and during thoracic surgery, and may play a role in postoperative hemodynamics. We studied changes in ir-NPY, epinephrine (E) and norepinephrine (NE) arterial plasma levels, and their correlation to simultaneous hemodynamic measurements at 8 perioperative time points in 13 patients undergoing open heart surgery.

[Evaluation of blood rheology indices in patients with pheochromocytoma].

Investigated group consisted of 28 patients (21 female and 7 male) with pheochromocytoma in mean age of 39.9 +/- 13 years, while control group comprised 25 healthy volunteers in mean age 36.0 +/- 7.

[Effect of positive pressure respiration on diurnal catecholamine excretion by patients with obstructive sleep apnea].

The aim of the study was to investigate effects of CPAP treatment on diurnal catecholamine excretion in urine in patients with obstructive sleep apnea (OSA). 12 males with severe OSA (mean AHI = 63) were measured in 3 separate 8 hour samples by fluorimetric method. NA levels were higher in OSA patients in all urine samples than in obese, mildly hypertensive males (control group = C).

Heart rate variability before sudden blood pressure elevations or complex cardiac arrhythmias in phaeochromocytoma.

In phaeochromocytoma, sudden hypertensive or arrhythmic episodes are believed to be associated with excessive free catecholamine excretion. However, lack of correlation between blood pressure (BP) and plasma catecholamine levels has been reported. Therefore an attempt was made to assess the sympathovagal balance before and during episodes of BP elevation or complex cardiac arrhythmias in this disease.