Polychlorinated biphenyls and testosterone: age and congener related correlation approach in heavily exposed males.

Objective: It was aimed to evaluate some fundamental correlations of 15 individual PCB congeners and their sum with serum testosterone level in highly and long-term exposed males with special respect to minimize the interfering effect of age.

Methods: A total of 834 males from eastern Slovakia (age range of 21-78 years; median, 75th and 90th percentile of 48, 54 and 58 years, respectively) were examined consisting of 432 males from highly polluted area and 402 males from the area of background pollution. In all of them the serum level of 15 polychlorinated biphenyl congeners (PCBs), hexachlorobenzene (HCB) and dichlorodiethyl-dichloroethylene (DDE) was measured by gas chomatography/mass spectrometry and total testosterone in serum was measured with the aid of electrochemiluminiscent immunoassay.

Increased prevalence and coincidence of antinuclear and antithyroid antibodies in the population exposed to high levels of polychlorinated pollutants cocktail.

Objectives: Because of well known association between the exposure to persistent organochlorinated pollutants (POPs) and impaired immune system, it was attempted to check possible coincidence of nuclear and thyroperoxidase antibodies with the levels of major POPs.

Methods: Antinuclear antibodies. (ANA) were estimated by indirect immunofluorescence test using Hep2- cells and thyroperoxidase antibodies (TPOab) by electrochemiluminiscent immunoassay in the cohort of 253 adults (82 males and 171 females) aged 21-75 years, among them 144 (46 males and 98 females) from the area polluted (POLL) by polychlorinated biphenyls (PCB) and 109 (36 males and 73 females) from the area of background pollutrion (BCGR).

Multiple adverse thyroid and metabolic health signs in the population from the area heavily polluted by organochlorine cocktail (PCB, DDE, HCB, dioxin).

Background: Several our previous studies showed associations of increasing blood level of persistent organochlorinated pollutants (POPs) with individual thyroid and metabolic adverse health signs in subjects from heavily polluted area (POLL) compared to these from the area of background pollution (BCGR). In this study we present increasing number of subjects with multiple adverse signs positively associated with blood level of polychlorinated biphenyls (PCBs) which is used as a marker of other POPs cocktail.

Methods: In a total of 2046 adults (834 males and 1212 females; age range 21-75) from POLL and BCGR the serum level of major POPs such as of 15 most abundant PCBs congeners, dichlorodiphenyl-dichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB) was estimated by high resolution gas chromatography.

Increased thyroid volume, prevalence of thyroid antibodies and impaired fasting glucose in young adults from organochlorine cocktail polluted area: outcome of transgenerational transmission?

In 137 females (F) and 94 males (M) aged 21-35 years from organochlorines (OCs) polluted area (POLL) increased thyroid volume (ThV), prevalence of antibodies to thyroperoxidase (TPOab), thyrotropin receptor (TRab) and of impaired fasting glucose (IFG) was found compared to 116 F and 107 M from background pollution area (BCGR). In F and M from POLL also strikingly increased level of PCBs, DDE and HCB was found. Such findings were compared to the generation of their parents aged 41-55 years consisting of 320F/213M from POLL and 406F/231M from BCGR.

Possible effects of persistent organochlorinated pollutants cocktail on thyroid hormone levels and pituitary-thyroid interrelations.

In polluted district of Michalovce in East Slovakia (POLL) and two districts with background pollution (BCGR) 2046 adults (834 males and 1212 females aged 20-75 years) were examined. Serum levels of thyrotropin (TSH), free thyroxine (FT4), total triiodothyronine (TT3) and antithyroperoxidase antibodies (TPOab) were estimated by electrochemiluminiscent assay and also these of 15 polychlorinated biphenyl congeners (PCBs), p,p'-DDE, p,p'-DDT, hexachlorobenzene (HCB) and hexachlorocyclohexane were measured by high resolution gas chromatography/mass spectrometry. In addition, also dioxins, furans, coplanar- and mono-ortho-PCBs as well as selected hydroxylated and methylsulphonated PCBs and DDE metabolites were measured by appropriate methods based on gas chromatography/mass spectrometry principle.

Thyroid ultrasound volume, structure and function after long-term high exposure of large population to polychlorinated biphenyls, pesticides and dioxin.

We examined 2,046 adults (834 males and 1,212 females aged 20-75 years) from polluted district in East Slovakia (POLL) and two neighboring upstream and upwind located districts of background pollution (BCGR). By ultrasound we estimated the thyroid volume (ThV), hypoechogenicity (HYE), nodules and cysts. Serum levels of thyrotropin (TSH), thyroperoxidase antibodies (TPOab) and thyroglobulin were estimated by electrochemiluminiscent assay and these of 15 PCB congeners, p,p'-DDE, p,p'-DDT, hexachlorobenzene (HCB) and hexachlorocyclohexane by high-resolution gas chromatography.

Fish from industrially polluted freshwater as the main source of organochlorinated pollutants and increased frequency of thyroid disorders and dysglycemia.

In a certain area of Michalovce district in East Slovakia, heavy industrial pollution by polychlorinated biphenyls (PCBs) developed in 1955-1984 and very high PCB levels in environmental and human samples are still persisting. Recently, a total of 2045 adults from this and the surrounding background pollution area have been examined using questionnaire data, thyroid volume by ultrasound (ThV), urinary iodine and serum levels of 15 PCB congeners, hexachlorobenzene (HCB), 2,2'-2-bis(4-chlorobiphenyl)-1,1-dichloroethylene (DDE), 2,2'-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), alpha-, beta- and gamma-hexachlorocyclohexane (HCH), thyrotropin (TSH), free thyroxine (FT4), anti-thyroperoxidase antibodies (TPOab) and fasting glucose. As based on our previous findings of strikingly high level of PCBs in fish from high pollution area (e.

Gene expression profiling of benign and malignant pheochromocytoma.

There are currently no reliable diagnostic and prognostic markers or effective treatments for malignant pheochromocytoma. This study used oligonucleotide microarrays to examine gene expression profiles in pheochromocytomas from 90 patients, including 20 with malignant tumors, the latter including metastases and primary tumors from which metastases developed. Other subgroups of tumors included those defined by tissue norepinephrine compared to epinephrine contents (i.

Insulin sensitivity indices: a proposal of cut-off points for simple identification of insulin-resistant subjects.

Demanding measurement of insulin sensitivity using clamp methods does not simplify the identification of insulin resistant subjects in the general population. Other approaches such as fasting- or oral glucose tolerance test-derived insulin sensitivity indices were proposed and validated with the euglycemic clamp. Nevertheless, a lack of reference values for these indices prevents their wider use in epidemiological studies and clinical practice.

Effect of space flight and head-down bedrest on neuroendocrine response to metabolic stress in physically trained subjects.

The aim of this study was to evaluate the association of plasma epinephrine (EPI) and norepinephrine (NE) responses to insulin induced hypoglycemia (ITT) 3 weeks before the space flight (SF), on the 5th day of SF, on the 2nd and 16th days after the landing in the first Slovak astronaut, and before and on the 5th day of prolonged subsequent head-down (-6 degrees) bed rest (BR) in 15 military aircraft pilots. Blood samples during the test were collected via cannula inserted into cubital vein, centrifuged in the special appliance Plasma-03, frozen in Kryogem-03, and at the end of the 8-day space flight transferred to Earth in special container for hormonal analysis. Insulin hypoglycemia was induced by i.

Low molecular weight proteomic information distinguishes metastatic from benign pheochromocytoma.

Metastatic lesions occur in up to 36% of patients with pheochromocytoma. Currently there is no way to reliably detect or predict which patients are at risk for metastatic pheochromocytoma. Thus, the discovery of biomarkers that could distinguish patients with benign disease from those with metastatic disease would be of great clinical value.

Phenylethanolamine N-methyltransferase gene expression in transplanted human heart.

Background: Phenylethanolamine N-methyltransferase (PNMT) is an enzyme involved in the epinephrine synthesis. The aim of this study was to investigate PNMT gene expression in the transplanted human heart in relation to the time elapsed from heart transplantation (HTx) and selected clinical characteristics.

Patients And Methods: The messenger RNA (mRNA) levels of PNMT in myocardial tissue were determined in 22 (21 males) patients at 0-12 years after HTx.

Downregulation of metastasis suppressor genes in malignant pheochromocytoma.

There is no reliable method currently available to predict malignant potential of pheochromocytoma based on conventional histology or genetic, molecular or immunohistochemical markers. Metastasis suppressor genes affect the spread of several cancers and, therefore, may provide promise as prognostic markers or therapeutic targets for malignant pheochromocytoma. We hypothesized that the downregulation of metastasis suppressor genes in malignant pheochromocytoma may play a role in malignant behavior.

Effects of endurance training on endocrine response to physical exercise after 5 days of bed rest in healthy male subjects.

The study was designed to evaluate how a bout of endurance training (ET) influences the endocrine response after head-down bed rest (HDBR). Eleven healthy males completed the study, which consisted of a 6-wk ET followed by 5 days of -6 degrees head-down HDBR. Treadmill exercise at 80% of pretraining maximal aerobic capacity (VO(2max)) was performed before and after ET as well as after HDBR.

Effects of space flight and -6 degrees bed rest on the neuroendocrine response to metabolic stress in physically fit subjects.

The aim of this study was to evaluate the association of plasma epinephrine (EPI) and norepinephrine (NE) responses to insulin-induced hypoglycemia (ITT) 3 weeks before the space flight (SF), on the fifth day of SF, on days 2 and 16 after landing in the first Slovak astronaut, and before and on the fifth day of prolonged bed rest (BR) in 15 military aircraft pilots, aged 33.5 +/- 1.4 years, body mass index (BMI) 26.

Effects of real and simulated microgravity on response of sympathoadrenal system to various stress stimuli.

Changes in plasma levels of epinephrine (EPI) and norepinephrine (NE) were investigated in humans exposed to physical exercise (WL), to psychic stressor (mental arithmetic test, MAT), and to oral glucose administration (oGTT) before and during a stay in microgravity (real space flight, SF) or in simulated microgravity (head-down bed rest, HDBR). A permanent cannula inserted into the cubital vein and a special appliance, Plasma-03, were used for blood collection, plasma separation, and freezing of samples during SF. Plasma EPI, NE, dihydroxyphenylglycol (DHPG), and dihydroxyphenylalanine (DOPA) levels were measured by the high-pressure liquid chromatography (HPLC) method.

Changes in gene expression of phenylethanolamine N-methyltransferase in the transplanted human heart.

Heart transplantation (HTx) is an accepted treatment for precisely defined patients with chronic congestive heart failure; however, as a result of the procedure, the graft is completely denervated. Our study focused on the catecholamine biosynthetic pathway, that is, the production of epinephrine, which is known to have positive chronotropic and inotropic effects on the heart. mRNA levels of the phenylethanolamine N-methyltransferase (PNMT), the enzyme catalyzing epinephrine synthesis in myocardial tissue, were determined in 18 patients (0 to 10 yr after HTx).

Repeated stress-induced stimulation of catecholamine response is not followed by altered immune cell redistribution.

Stress response is considered an important factor in the modulation of immune function. Neuroendocrine hormones, including catecholamines, affect the process of immune cell redistribution, important for cell-mediated immunity. This longitudinal investigation was aimed at evaluating the effect of repeated stress-induced elevation of catecholamines on immune cell redistribution and expression of adhesive molecules.

Thyroid function and cholesterol level: paradoxical findings in large groups of population with high cholesterol food intake.

Objective: To compare the levels of serum cholesterol with thyroid function as estimated by the level of thyrotropin and free thyroxine with possible participation of thyroperoxidase antibodies in large number of adults examined within large field surveys focused on the evaluation of thyroid status of Slovak rural population.

Subjects And Methods: Serum level of cholesterol and thyrotropin (TSH) was estimated in a total of 2786 adults. In addition, in 2038 of them also the level of free thyroxine (FT4), total triiodothyronine (TT3), cholesterol, triglycerides and phospholipids was measured.

Responses of sympathoadrenal and renin angiotensin systems to stress stimuli in humans during real and simulated microgravity.

Changes of plasma hormone levels were investigated in human subjects after exposure to physical exercise (WL) and insulin induced hypoglycemia (ITT) during space flight or after head down bed rest (HDBR). Exaggerated responses of plasma epinephrine (EPI), norepinephrine (NE) and aldosterone (ALD) were observed after WL during space flight as compared to preflight response. Hypoglycemia during space flight induced attenuated responses of EPI, NE and augmented response of ALD.

The response of endocrine system to stress loads during space flight in human subject.

The responses of endocrine system to the exposure to stress-work load and hormonal changes during oral glucose tolerance tests were studied in the Slovak astronaut before (three weeks before flight), during (on the 4th and the 6th days of space flight), and after space flight (1-3 days and 15-17 days after space flight) on board of space station MIR. Blood samples during the tests were collected via cannula inserted into cubital vein, centrifuged in the special appliance Plasma-03, frozen in Kryogem-03, and at the end of the 8-day space flight transferred to Earth in special container for hormonal analysis. Preflight workload produced an increase of plasma norepinephrine and a moderate elevation of epinephrine levels.

[Use of the in vivo microdialysis technique in basic and clinical research].

Microdialysis is in vivo technique that permits monitoring of local concentrations of metabolites and drugs at specific sites in the body that makes it an attractive tool for the basic and clinical research. Microdialysis entered the experimental studies of the brain, and later also of the peripheral tissues such as adipose and muscle tissues, kidney, lung, eye, skin, and blood. There are several critical factors in the experimental implementations of microdialysis: the probe, the perfusion solution, tissue integrity, and the sensitivity of microdialysate analysis method.

Effect of head-down bed rest on the neuroendocrine response to orthostatic stress in physically fit men.

The role of neuroendocrine responsiveness in the development of orthostatic intolerance after bed rest was studied in physically fit subjects. Head-down bed-rest (HDBR, -6 degrees, 4 days) was performed in 15 men after 6 weeks of aerobic training. The standing test was performed before, after training and on day 4 of the HDBR.

Plasma hormone levels in human subject during stress loads in microgravity and at readaptation to Earth's gravity.

In great part of the investigations of endocrine system functions in astronauts during space flights the plasma levels of hormones and metabolites were determined only in resting conditions, usually from one blood sample collection. Such levels reflected the psychical and physical state and new hormonal homeostasis of organism at the time of blood collection, however, the functional capacity of neuroendocrine system to respond to various stress stimuli during space flight remained unknown. The aim of present investigations was to study dynamic changes of hormone levels during the stress and metabolic loads (insulin induced hypoglycemia, physical exercise and oral glucose tolerance test) at the exposure of human subject to microgravity on the space station MIR.

Effect of microgravity on plasma catecholamine responses to stressors during space flight.

The effect of microgravity on the sympathicoadrenal system (SAS) activity in humans and animals has not yet been clarified. Our previous studies suggested that the SAS activity, evaluated by circulating and/or urinary catecholamine (CA) levels in astronauts during space flights, was found to be rather unchanged. However, CA levels were measured in astronauts only at rest conditions.