107 results on '"A. G. Vagenakis"'
Search Results
2. Impaired Pharmacokinetics of Levothyroxine in Severely Obese Volunteers
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Amalia Faltaka, Fotios Kalfarentzos, Marina Michalaki, Apostolos G. Vagenakis, Kostas B. Markou, Irene Mamali, Georgios K. Markantes, and Margarita I. Gkotsina
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Adult ,Male ,Thyroid Hormones ,endocrine system ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Levothyroxine ,Thyrotropin ,Physiology ,Body Mass Index ,Cohort Studies ,Endocrinology ,Pharmacokinetics ,Internal medicine ,medicine ,Humans ,Euthyroid ,Obesity ,Autoantibodies ,Triiodothyronine ,business.industry ,Body Weight ,Case-control study ,medicine.disease ,Thyroxine ,Area Under Curve ,Case-Control Studies ,Lean body mass ,Female ,business ,Body mass index ,medicine.drug - Abstract
Suppressive or replacement doses of levothyroxine (LT4) are affected by the rate and extent of the active ingredient absorbed, as well as by the lean body mass. Obesity has reached epidemic proportions worldwide and is related with many comorbidities. The aim of this study was to determine the pharmacokinetic parameters of LT4 in severely obese individuals and compared them with similar data in lean control subjects.We studied 62 euthyroid subjects who had negative tests for anti-thyroid peroxidise antibodies (Ab-TPO). Thirty eight of these subjects were severely obese but otherwise healthy (severe obese subjects [SOS] group). Twenty-four were healthy control subjects (control group), with a body mass index of 23.3 ± 1.7 kg/m(2). Subjects received 600 μg oral sodium LT4 after an overnight fast. Serum triiodothyronine (T3), T4, and thyroid-stimulating hormone were measured at baseline. Serum T4 and T3 was measured 0.5, 1, 1.5, 2, 2.5, 3, and 4 hours after LT4 administration.Baseline serum T4 and thyroid-stimulating hormone concentrations were higher in the SOS group than in the control group; serum T3 was similar in the two groups. The corrected area under the curve and the maximum T4 concentration after LT4 administration were lower, whereas the time to maximum concentration from the baseline was higher in SOS than in the control group. The estimated plasma volume was higher in the SOS than in the control group. Mean serum T3 levels increased gradually during the four hours after LT4 administration in the control group. In contrast, they decreased gradually in the SOS group.Severely obese individuals may need higher LT4 suppressive or replacement doses than normal-weight individuals due, among other factors, to impaired LT4 pharmacokinetic parameters. The latter could be attributed to their higher plasma volume and/or to delayed gastrointestinal LT4 absorption. T4 conversion to T3 might be defective in severe obesity.
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- 2011
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3. Abolished circadian rhythm of salivary cortisol in elite artistic gymnasts
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Athanasios Tsekouras, Anastasia Theodoropoulou, Kostas B. Markou, Loredana Rottstein, Eftychia Koukkou, Apostolos G. Vagenakis, Michel Leglise, Neoklis A. Georgopoulos, Panagiotis Mylonas, Evgenia Lampropoulou, George Polykarpou, and Gregoris Iconomou
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Male ,medicine.medical_specialty ,Saliva ,Adolescent ,Gymnastics ,Hydrocortisone ,Clinical Biochemistry ,Physical exercise ,Biochemistry ,Endocrinology ,Internal medicine ,Humans ,Medicine ,Body Weights and Measures ,Circadian rhythm ,Thelarche ,Molecular Biology ,Morning ,Pharmacology ,business.industry ,Adrenarche ,Organic Chemistry ,Bone age ,Circadian Rhythm ,Case-Control Studies ,Lean body mass ,Regression Analysis ,Female ,business ,Stress, Psychological - Abstract
The aim of this study was to evaluate the effects of intensive physical exercise and acute psychological stress during high level athletic competition as reflected on the levels of salivary cortisol in elite artistic gymnasts (AGs).The study included 239 AGs (142 females-97 males) who participated in the European Championship of Gymnastics in 2006 and 81 adolescents (40 females-41 males), matched for age, as controls. All athletes participated voluntarily in all or parts of the study, providing samples or data for each of the variables measured. Height, weight, body fat, lean body mass (LBM), bone age and Tanner stage of puberty were assessed and data concerning the time of thelarche, adrenarche and menarche as well as, the onset and the intensity (hours per week) of training were obtained.Saliva samples were collected, the morning before training and in the afternoon shortly after the competition. From controls, the saliva samples were collected in the morning. Cortisol concentrations were measured using a chemiluminescence method. Acute stress was assessed using a questionnaire designed for the study.No difference was found between morning and afternoon salivary cortisol levels in both male and female AGs (females: AM: 15.45±7.45nmol/l vs PM: 15.73±9.38nmol/l; males: AM: 10.21±5.52nmol/l vs PM: 9.93±13.8nmol/l, p0.05). Female AGs presented higher levels of morning salivary cortisol than female controls (p0.05). Both male and female AGs had higher degree of psychological stress in comparison with controls (p0.001, p0.013, respectively). Female AGs had higher morning and afternoon salivary cortisol levels (p0.01, p0.01, respectively) and higher degree of stress (p0.003) than males.In elite AGs the diurnal rhythm of salivary cortisol has been abolished, probably due to the strenuous training and competition conditions. Female AGs presented higher levels of morning salivary cortisol and psychological stress compared to both male AGs and female controls. The long term consequences of these modifications of the HPA axis remain to be elucidated.
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- 2011
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4. The influence of intensive physical training on growth and pubertal development in athletes
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Neoklis A. Georgopoulos, Kostas B. Markou, Nikolaos D. Roupas, Athanasios Tsekouras, Anastasia Theodoropoulou, and Apostolos G. Vagenakis
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medicine.medical_specialty ,biology ,Athletes ,business.industry ,General Neuroscience ,Physical fitness ,biology.organism_classification ,Affect (psychology) ,Child development ,General Biochemistry, Genetics and Molecular Biology ,Endocrinology ,History and Philosophy of Science ,Internal medicine ,Prepubertal stage ,Genetic predisposition ,medicine ,Bone maturation ,Menarche ,business ,human activities - Abstract
Genetic potential for growth can be fully expressed only under favorable environmental conditions. Although moderate physical activity has beneficial effects on growth, excessive physical training may negatively affect it. Sports favoring restricted energy availability, in the presence of high energy expenditure, are of particular concern. In gymnastics, a different pattern in skeletal maturation and linear growth was observed, resulting in an attenuation of growth potential in artistic gymnasts (AG), more pronounced in males than in females. In female rhythmic gymnasts (RG), the genetic predisposition to growth was preserved owing to a late catchup growth phenomenon. In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented so far. Intensive physical training and negative energy balance alter the hypothalamic pituitary set point at puberty, prolong the prepubertal stage, and delay pubertal development and menarche in a variety of sports. In elite RG and AG, prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, following the bone maturation rather than the chronological age.
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- 2010
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5. Hypothalamic–pituitary–adrenal axis response to the severity of illness in non-critically ill patients: does relative corticosteroid insufficiency exist?
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Venetsana Kyriazopoulou, A Tsekouras, Apostolos G. Vagenakis, Marina Michalaki, T Margeli, and C H Gogos
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Male ,Hypothalamo-Hypophyseal System ,endocrine system ,medicine.medical_specialty ,Hydrocortisone ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Pituitary-Adrenal System ,Severity of Illness Index ,Sepsis ,Endocrinology ,Adrenocorticotropic Hormone ,Stress, Physiological ,Internal medicine ,Severity of illness ,medicine ,Humans ,Stroke ,Aged ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Circadian Rhythm ,medicine.anatomical_structure ,Ischemic Attack, Transient ,Hypothalamus ,Acute Disease ,Chronic Disease ,Corticosteroid ,Female ,business ,hormones, hormone substitutes, and hormone antagonists ,Glucocorticoid ,Hypothalamic–pituitary–adrenal axis ,medicine.drug - Abstract
ObjectiveRelative corticosteroid insufficiency may be common in critically ill patients and is associated with a poor outcome; however, the response of the hypothalamic–pituitary–adrenal (HPA) axis in nursed patients is not known. Our aim was to evaluate the response of HPA axis to the severity of illness in non-critically ill nursed (NCIN) patients and the clinical outcome.Subjects and methodsFifty-six nursed patients who were divided into four groups (stroke, mild disease, sepsis and severe sepsis) as well as a control group (n=15) were studied. At admission (day 1), cortisol and ACTH were measured and a low-dose (1 μg) corticotrophin test was performed, followed 2 h later by a standard-dose (250 μg) corticotrophin test. Diurnal variation of cortisol was obtained on day 2. A second identical set of low-dose and standard-dose corticotrophin tests were performed on day 5 or 6 (recovery phase).ResultsIn patients with stroke and severe sepsis, cortisol had the highest values and its diurnal variation was abolished. Dissociation of ACTH and cortisol was found in all patients.The Δmax of cortisol after the 1-μg corticotrophin test did not differ among the groups, while after the 250-μg corticotrophin test, it was borderline higher in controls. The ratio of responders (Δmax of cortisol ≥9 μg/dl) to non-responders after 1- or 250-μg corticotrophin test did not differ among patients and controls. All patients had a good outcome without glucocorticoid treatment.ConclusionsDepending on the severity of illness, mild alterations in the HPA axis occurred. However, relative corticosteroid insufficiency was not confirmed in NCIN patients.
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- 2010
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6. The Odyssey of Nontoxic Nodular Goiter (NTNG) in Greece under Suppression Therapy, and after Improvement of Iodine Deficiency
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Kostas B. Markou, Panagiota Paraskevopoulou, Marina Michalaki, Apostolos G. Vagenakis, and Venetsana Kyriazopoulou
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Adult ,Male ,endocrine system ,medicine.medical_specialty ,Goiter ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Thyroid Gland ,Thyrotropin ,chemistry.chemical_element ,Iodine ,Hyperthyroidism ,Gastroenterology ,Thyroid function tests ,Group B ,Endocrinology ,Risk Factors ,Internal medicine ,Prevalence ,medicine ,Humans ,Prospective Studies ,Aged ,Retrospective Studies ,Aged, 80 and over ,Triiodothyronine ,Dose-Response Relationship, Drug ,Greece ,medicine.diagnostic_test ,business.industry ,Contraindications ,Incidence (epidemiology) ,Middle Aged ,medicine.disease ,Iodine deficiency ,Surgery ,Thyroxine ,Thyrotoxicosis ,chemistry ,Female ,Thyroid function ,business ,Goiter, Nodular - Abstract
Nontoxic nodular goiter (NTNG) is common in endemic goiter regions. Thyroxine (T4) is often used to treat NTNG. There is little information regarding T4 treatment in regions that have recently become iodine sufficient. We studied the effect of T4 treatment on thyroid function tests in southwestern Greece (SWG), a recently iodine-sufficient area.We studied 827 residents of SWG (group A) to determine goiter prevalence, thyroid function, and urinary iodine concentration (UIC). Group B: 385 consecutive patients with thyroid dysfunction. Of these, 89 had NTNG and followed for 10 years on T4 treatment, and 296 had hyperthyroidism. Group C: 29 patients with NTNG, treated with triiodothyronine (T3) 50 mug/day and followed for 6 months. Measurements included serum T4 and 24-hour radioactive iodine uptake (RAIU) before and at the end of T3 administration.The median UIC in group A was 114 microg/L. In group B (89 patients), the incidence of newly diagnosed hyperthyroidism was 5-7% per year with a cumulative percentage of 33% at the 10th year. The initial thyrotropin (TSH) was lower (0.78 +/- 0.51 mIU/L) in those who developed thyrotoxicosis compared to those who remained euthyroid (1.17 +/- 0.74 mIU/L) (p0.05). In 296 thyrotoxic patients, the incidence of autoimmune hyperthyroidism and toxic multi-nodular goiter (TMNG) was similar. In group C, 10/29 patients remained euthyroid and the 24-hour RAIU decreased by 49% during T3 treatment. Similarly, serum T4 decreased by 49%. In the remaining patients who developed hyperthyroidism, 24-hour RAIU and T4 were decreased by 19% and 22%, respectively.In SWG, a recently iodine-sufficient region, the risk of developing hyperthyroidism in patients with NTNG after administration of 100-150 microg T4 is relatively high in those whose serum TSH before T4 treatment is in the lower normal range. Therefore, T4 treatment should be avoided in these patients.
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- 2008
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7. Glucose Levels and Insulin Secretion in Surgery-Induced Hyperglycemia in Normoglycemic Obese Patients
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Venetsana Kyriazopoulou, Apostolos G. Vagenakis, Maria-Ioanna Argentou, Marina Michalaki, Panagiotis Mylonas, Fotis Kalfarentzos, and Yves Debaveye
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Adult ,Male ,medicine.medical_specialty ,Time Factors ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Body Mass Index ,Insulin resistance ,Internal medicine ,Insulin Secretion ,medicine ,Humans ,Insulin ,Postoperative Period ,Elective surgery ,Insulin secretion ,Nutrition and Dietetics ,business.industry ,Severe obesity ,medicine.disease ,Obesity, Morbid ,Surgery ,Endocrinology ,Elective Surgical Procedures ,Hyperglycemia ,Female ,Preoperative fasting ,Insulin Resistance ,business ,Body mass index - Abstract
Transient hyperglycemia is commonly observed in non-diabetic subjects during surgery. We undertook this study to investigate (1) insulin secretion pattern and glucose levels during elective surgery, and (2) the role of pre-operative fasting in the development of surgery-induced hyperglycemia.We examined 21 severely obese normal glucose tolerant patients, who underwent bariatric surgery. From the 21 operated subjects, 14 remained fasted while seven patients received 75 g glucose the preoperative night. They sampled at baseline and from the onset of operation frequently for 9 h thereafter, for measuring serum insulin and glucose.Hyperglycemia developed within 1 h from the onset of operation and lasted 9 h. The administration of 75 g glucose the preoperative night prevented surgery-induced hyperglycemia. Insulin profile analyzed by deconvolution analysis was similar between fasted patients and those who received 75 g glucose. Serum insulin was suppressed at the beginning of the surgery and reached baseline values 4 h thereafter.Hyperglycemia occurred within 1 h from the beginning of surgery and sustained for at least 9 h while insulin levels are suppressed or unaltered compared to baseline values in euglycemia. The administration of 75 g glucose the preoperative night prevents surgery-induced hyperglycemia without altering the profile of insulin secretion.
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- 2008
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8. Thyroid Function in Humans with Morbid Obesity
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Aggeliki S. Leonardou, Agathoklis Psyrogiannis, Venetsana Kyriazopoulou, Ioannis Habeos, Maria Makri, Apostolos G. Vagenakis, Marina Michalaki, Fotis Kalfarentzos, and Marianna Argentou
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Adult ,Blood Glucose ,Leptin ,Male ,endocrine system ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Thyroid Gland ,Levothyroxine ,Thyrotropin ,Thyroid Function Tests ,Iodide Peroxidase ,Gastroenterology ,Thyroid function tests ,Body Mass Index ,Cohort Studies ,Endocrinology ,Hypothyroidism ,Internal medicine ,medicine ,Humans ,Insulin ,Euthyroid ,Subclinical infection ,Triiodothyronine ,Anthropometry ,medicine.diagnostic_test ,business.industry ,Thyroid ,Glucose Tolerance Test ,Middle Aged ,Obesity, Morbid ,Thyroxine ,medicine.anatomical_structure ,Cohort ,Female ,Thyroid function ,business ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Morbidly obese subjects may present with abnormal thyroid function tests but the reported data are scarce. Therefore, we studied the thyroid parameters in 144 morbidly obese patients, 110 females and 34 males, to assess the prevalence of hypothyroidism. Eleven percent (11.8%) carried the diagnosis of hypothyroidism and were undergoing levothyroxine (LT4) replacement therapy, 7.7% had newly diagnosed subclinical hypothyroidism, 0.7% had subclinical hyperthyroidism and 7.7% were euthyroid with positive antibodies (anti-thyroid peroxidase antibodies [TPOAb]). From the 144 subjects, we selected a cohort of 78 euthyroid subjects with negative TPOAb, who did not receive LT4 replacement or suppression therapy (the experimental group) and compared them to 77 normal-weight euthyroid subjects, TPOA-negative, matched for age and gender who served as controls. The experimental group had higher serum levels of triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), and thyrotropin (TSH) compared to the control group. Serum TSH concentration was associated with fasting serum insulin levels and insulin resistance but not with serum leptin levels, body mass index (BMI), fat mass, and lean body mass. In conclusion, in morbidly obese individuals, the prevalence of overt and subclinical hypothyroidism was high (19.5%). The morbidly obese subjects have higher levels of T3, FT3, T4, and TSH, probably the result of the reset of their central thyrostat at higher level.
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- 2006
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9. Inappropriately low erythropoietin response for the degree of anemia in patients with noninsulin-dependent diabetes mellitus
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Apostolos G. Vagenakis, Venetsana Kyriazopoulou, Alexandra Kouraklis-Symeonidis, Argiris Symeonidis, Michalis Leotsinidis, Pavlos Vassilakos, Agathoklis Psiroyiannis, and Nicholas C. Zoumbos
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Adult ,Male ,medicine.medical_specialty ,Glycosylation ,Anemia ,Population ,Pathogenesis ,Hemoglobins ,hemic and lymphatic diseases ,Internal medicine ,Diabetes mellitus ,Humans ,Medicine ,Hypoxia ,Megaloblastic anemia ,education ,Erythropoietin ,Aged ,Aged, 80 and over ,Glycated Hemoglobin ,education.field_of_study ,Hematology ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Endocrinology ,Diabetes Mellitus, Type 2 ,Cytokines ,Female ,Hemoglobin ,business ,medicine.drug - Abstract
We investigated erythropoietin (Epo) response in a cohort of diabetic patients with various types of anemia to approach the pathogenesis of some cases of "unexplained" anemia encountered among diabetics. Serum Epo levels were determined totally in 747 evaluable subjects with normal renal and hepatic function, of whom 694 had anemia. Among anemic patients, 237 were diabetics, while among the 53 nonanemic persons, there were also 21 diabetics. Diabetic and nondiabetic subjects were uniformly balanced in relation to their demographic features and were categorized according to the etiology of their anemia. Hemoglobin (Hb) did not differ between diabetic and nondiabetic subjects in all the etiological groups and in the whole population. Diabetic patients had significantly lower serum Epo levels as compared to nondiabetics (36.5+/-61 vs 69.4+/-191 IU/ml, p0.0001), and this was true for all etiologic groups of anemia with the exception of patients with myeloproliferative disorders and those with megaloblastic anemia. The natural logarithmic (ln)-EpoxHb component was used as an index of response to anemia and was found to be significantly decreased in almost all subgroups of diabetic patients. Serum Epo levels were also negatively correlated with the percentage of glycosylated Hb, HbA1(C) (r=-0.446), and the correlation was stronger with the ln of serum Epo (r=-0.638, p0.001). Inappropriately low serum Epo level is a uniform feature in patients with type II diabetes mellitus and may represent a constitutive blunted response to anemia or an altered metabolic rate of Epo, probably as a result of abnormal glycosylation of the cytokine.
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- 2005
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10. Statins and transcriptional regulation: The FXR connection
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Apostolos G. Vagenakis, Panos G. Ziros, Ioannis Habeos, Agathoklis Psyrogiannis, and Athanasios G. Papavassiliou
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Male ,Transcriptional Activation ,Simvastatin ,medicine.medical_specialty ,Statin ,medicine.drug_class ,Biophysics ,Administration, Oral ,Receptors, Cytoplasmic and Nuclear ,Biology ,Biochemistry ,Cell Line ,Cricetinae ,Internal medicine ,Transcriptional regulation ,medicine ,Animals ,Tissue Distribution ,cardiovascular diseases ,Receptor ,Molecular Biology ,Cells, Cultured ,Regulation of gene expression ,Carbohydrate homeostasis ,Mesocricetus ,nutritional and metabolic diseases ,Cell Biology ,DNA-Binding Proteins ,Endocrinology ,Gene Expression Regulation ,Liver ,Nuclear receptor ,Hypolipidemic Agents ,Hepatocytes ,lipids (amino acids, peptides, and proteins) ,Farnesoid X receptor ,Transcription Factors - Abstract
Farnesoid X receptor (FXR) is a nuclear receptor involved in lipoprotein as well as glucose metabolism. Statins are widely used hypolipidemic agents with many pleiotropic actions. It is known that statins affect other nuclear hormone receptors, but no reports are available on the effect of these drugs on FXR. Employing an animal model (Syrian hamsters), we hereby present evidence to demonstrate that Simvastatin, a broadly prescribed statin, decreases the expression of FXR at both the RNA and protein levels and down-regulates its DNA-binding activity. This novel property may have important implications on the mode statins influence on lipoprotein and carbohydrate homeostasis in the organism.
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- 2005
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11. Kallmann's Syndrome and Schizophrenia
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Venetsanos Mavreas, George A. Vagenakis, Argyro Sgourou, Apostolos G. Vagenakis, Anthi Protonatariou, Charalabos Papageorgiou, Panayotis A. Dimopoulos, Neoklis A. Georgopoulos, and Thomas Hyphantis
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Adult ,Paranoid schizophrenia ,Psychosis ,medicine.medical_specialty ,Pediatrics ,Kallmann syndrome ,Hypothalamus ,Anosmia ,Olfaction Disorders ,03 medical and health sciences ,0302 clinical medicine ,MMPI ,Pituitary Gland, Anterior ,Hyposmia ,Hypogonadotropic hypogonadism ,Surveys and Questionnaires ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Hypogonadism ,Brain ,Kallmann Syndrome ,medicine.disease ,Magnetic Resonance Imaging ,Olfactory Bulb ,030227 psychiatry ,Diagnostic and Statistical Manual of Mental Disorders ,Psychiatry and Mental health ,Endocrinology ,Schizophrenia ,Female ,Atrophy ,medicine.symptom ,Psychology ,Kallmann's syndrome - Abstract
Objective: Kallmann's Syndrome is a heritable disorder characterized by the association of hypogonadotropic hypogonadism and anosmia or hyposmia. A common pathogenesis for KS and schizophrenia had been proposed based on shared pathologies of these two disorders, although no such clinical associations have ever been reported. Method: We report a 35 year old man with schizophrenia and Kallmann's Syndrome. The patient presented with signs and symptoms of hypogonadism, severe hyposmia and normal endocrine functions of the anterior pituitary. Hyposmia has been attributed to the absence of the olfactory bulbs and tracts and atrophy of the olfactory gyri, but normal olfactory mucosa. The patient presented with paranoid schizophrenia with persecutory delusions, auditory hallucinations, thought disorder, depersonalization, and gradual but marked global deterioration. Results: Psychiatric evaluation revealed an entirely different psychopathological and personality profile between the patient and the six other Kallmann patients studied. Cycle sequencing analysis revealed a normal sequence of all 14 exons of the KAL gene. In conclusion, based on the presented case, Kallmann's Syndrome and schizophrenia represent a rare clinical association rather than a syndrome with a common pathogenesis, which if present should be confined to the olfactory dysfunction.
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- 2004
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12. Relative Iron 'Overload' in Offspring of Patients with Type 2 Diabetes Mellitus: A New Component in the Conundrum of Insulin Resistance Syndrome?
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Venetsana Kyriazopoulou, Agathoklis Psyrogiannis, Michalis Leotsinidis, Apostolos G. Vagenakis, and Argiris Symeonidis
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medicine.medical_specialty ,medicine.diagnostic_test ,biology ,Transferrin saturation ,business.industry ,Offspring ,Endocrinology, Diabetes and Metabolism ,Insulin ,medicine.medical_treatment ,General Medicine ,Type 2 diabetes ,medicine.disease ,Ferritin ,Endocrinology ,Insulin resistance ,Total iron-binding capacity ,Internal medicine ,Serum iron ,medicine ,biology.protein ,business - Abstract
There are a few reports suggesting that subtle disturbances of iron metabolism are frequently found in patients with type 2 diabetes (DM2), but it is not known if these disturbances precede or accompany the diabetic state. We investigated the serum iron indices in 41 offspring of DM2 parents (group I) with normal glucose tolerance, and in 49 offspring whose parents had no history of DM2 and were matched for sex, age, body mass index (BMI), waist to hip ratio (WHR) and blood pressure (group II). Serum iron, ferritin, total iron binding capacity (TIBC), transferrin saturation, serum triglycerides, cholesterol, Apo-B, high density lipoprotein (HDL) and glucose and insulin values during an oral glucose tolerance test were measured. Insulin resistance was assessed using the homeostasis model assessment (HOMA - Insuline resistence index-IRI). In comparison to controls (group II), the offspring of DM2 subjects (group I) had higher fasting serum triglycerides (mean +/- SD 2.25+/-2.08 vs. 1.6+/-0.8 mmol/L, p
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- 2003
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13. Hyperthyrotropinemia during Iodide Administration in Normal Children and in Children Born with Neonatal Transient Hypothyroidism
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Maria Makri, Apostolos G. Vagenakis, Panagiota Paraskevopoulou, Gregoris Iconomou, Neoklis A. Georgopoulos, Kostas B. Markou, Konstantinos S. Karaiskos, and Chryssanthi Mengreli
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Male ,endocrine system ,medicine.medical_specialty ,Adolescent ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Iodide ,Thyrotropin ,Thyroglobulin ,Biochemistry ,Infant, Newborn, Diseases ,Group B ,Endocrinology ,Hypothyroidism ,Thyroid-stimulating hormone ,Thyroid peroxidase ,Internal medicine ,Blood plasma ,Congenital Hypothyroidism ,medicine ,Humans ,Child ,chemistry.chemical_classification ,biology ,business.industry ,Biochemistry (medical) ,Age Factors ,Infant, Newborn ,Iodides ,Thyroxine ,chemistry ,biology.protein ,Triiodothyronine ,Female ,Thyroid function ,business ,Hormone - Abstract
The aim of the present study was to examine the effects of chronic iodide administration in pharmacological doses on thyroid function in children with a history of transient congenital hypothyroidism (TCH). We hypothesized that such children may carry a previously undisclosed intrinsic intrathyroidal defect, rendering them susceptible to TCH. We administered for this 60-65 mg iodide daily for 60 d in 13 individuals with TCH (group A), 8 of their siblings (group B), 8 healthy controls (group C), and 11 normal adults (group D). Thyroid function was evaluated by measuring serum T(3), T(4), free T(3), free T(4), TSH, and thyroglobulin concentrations and autoantibodies against thyroid peroxidase and thyroglobulin at baseline at 15, 30, and 60 d during iodide administration, and 2 months after iodide withdrawal. Hyperthyrotropinemia greater than 4.2 mU/liter but not higher than 10 mU/liter with normal thyroid hormone concentrations was observed in one of the TCH group and in two of the group B siblings. During iodide administration, hyperthyrotropinemia was observed in 8 of 13 (62%) adolescents in group A, 4 of 7 (57%) in group B, and 6 of 8 (75%) in group C. None of the 11 adults (group D) developed hyperthyrotropinemia during iodide administration. Serum T(4) and free T(4) concentrations were decreased in all groups when compared with baseline values. The magnitude of the decrease of serum T(4) was identical in all groups (0.7-0.8 microg/dl). Thyroid enlargement was observed in all subjects and was more pronounced in children. There were no cases of subclinical and/or overt hyperthyroidism. After iodine withdrawal, serum TSH decreased in all groups and returned to baseline levels, as well as the thyroid volume. In conclusion, the hypothalamic-pituitary-thyroid axis of adolescents with TCH responds to pharmacological doses of iodide similarly to that observed in normal children. The hyperthyrotropinemia observed in the adolescents exposed to iodides may reflect incipient transient hypothyroidism or simply a brisk TSH response to a small serum T(4) decrease. Whatever the mechanism, chronic use of excessive quantities of iodide should be avoided until the end of puberty.
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- 2003
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14. Growth Retardation in Artistic Compared with Rhythmic Elite Female Gymnasts
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Apostolos G. Vagenakis, Dan Benardot, Neoklis A. Georgopoulos, Michel Leglise, Anastasia Theodoropoulou, and Kostas B. Markou
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Adult ,medicine.medical_specialty ,Percentile ,Adolescent ,Gymnastics ,Body height ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Growth ,Body weight ,Biochemistry ,Body Mass Index ,Endocrinology ,Internal medicine ,medicine ,Humans ,Child ,Growth Disorders ,Growth retardation ,business.industry ,Population mean ,Body Weight ,Biochemistry (medical) ,Anthropometry ,Body Height ,Rhythmic gymnastics ,Female ,business ,Body mass index - Abstract
We studied 129 female rhythmic gymnasts (RG) and 142 female artistic gymnasts (AG) who participated in the 1999 Gymnastics World Championship for RG in Osaka, Japan, and the 1999 and 2001 Gymnastics World Championships for AG in Tianjin, China (n 48), and Ghent, Belgium (n 94), respectively. RG were taller than average, with a mean height SD score above the 50th percentile, whereas AG were relatively short, with a mean height SD score below the 50th percentile. Both RG and AG followed their respective reported target height SD score, which was above the 50th percentile for the RG and below the 50th percentile for the AG. The RG followed a growth pattern that was higher than their reported target height, whereas AG exhibited a negative growth pattern. RG and AG weighed less than the population mean, with the mean weight for age below the 50th percentile for both groups. RG were taller than AG (t 17.15; P < 0.001), with a higher reported target height SD score (t 6.44; P < 0.001), a greater height-reported target height (t 2.74; P < 0.001), and a lower mean body fat (t 11.83; P < 0.001) and body mass index (t 10.73; P < 0.001) than AG. AG started their training at an earlier age than RG (t 4.13; P < 0.001). Using multiple regression analysis, actual height SD score was independently influenced positively by weight SD score for both RG (b 0.421; t 4.317; P < 0.001) and AG (b 1.404; t 16.514; P
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- 2002
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15. Identification of Iodine Deficiency in the Field by the Rapid Urinary Iodide Test: Comparison with the Classic Sandell-Kolthoff Reaction Method
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Eleni Anastasiou, Kostas B. Markou, Maria Makri, George Sakellaropoulos, Barbara Vlasopoulou, Neoklis A. Georgopoulos, Apostolos G. Vagenakis, Nikolaos Lazarou, and George A. Vagenakis
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Male ,medicine.medical_specialty ,Azerbaijan ,Goiter ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Population ,Iodide ,Urology ,chemistry.chemical_element ,Urine ,World Health Organization ,Iodine ,Endocrinology ,medicine ,Humans ,Mass Screening ,Child ,education ,Developing Countries ,Mass screening ,chemistry.chemical_classification ,education.field_of_study ,business.industry ,Gold standard (test) ,Iodides ,medicine.disease ,Iodine deficiency ,Surgery ,chemistry ,Colorimetry ,Female ,Spectrophotometry, Ultraviolet ,business - Abstract
The two traditional methods for the assessment of iodine deficiency in a given area are the estimation of urinary excretion of iodine, and the prevalence of goiter. In field studies, the estimation of urinary iodine excretion (UIE) in random urine specimens provides an adequate assessment of a population's iodine nutrition. The recommended method is the classic one, based on Sandell-Kolthoff reaction (Method A). Recently, a new semi-quantitative method has been introduced (rapid urinary iodide test [RUIT]). We performed a field study in a developing country (Azerbaijan) in order to compare the classic Method A to RUIT. The study included 942 schoolchildren, to whom UIE was estimated by RUIT. Comparing the two methods, (n = 260), the sensitivity of RUIT using as gold standard Method A, was 96% and the specificity was 61%. The correlation between median values UIE estimated by RUIT and by Method A was excellent (r = 0.98, p < 0.001). An agreement in iodine deficiency classification according to the World Health Organization-United Nations Children's Fund-International Council for the Control of Iodine-Deficiency Disorders (WHO-UNICEF-ICCIDD) between the two methods was observed in eight of nine areas. In conclusion, RUIT is a suitable method for UIE estimation in field studies of suspected iodine deficiency. The test is relatively inexpensive, easy to perform, and does not require sophisticated instruments.
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- 2002
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16. Iodine Deficiency in Azerbaijan After the Discontinuation of an Iodine Prophylaxis Program: Reassessment of Iodine Intake and Goiter Prevalence in Schoolchildren
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Rauf Jabbarov, Larissa Deville, Neoklis A. Georgopoulos, George A. Vagenakis, Chrisanthi Megreli, Maria Makri, Kostas B. Markou, Eleni Anastasiou, Apostolos G. Vagenakis, Nikolaos Lazarou, Barbara Vlasopoulou, Marina G. Kerimova, George Sakellaropoulos, and Rafig M. Mamedgasanov
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Male ,endocrine system ,medicine.medical_specialty ,Pediatrics ,Azerbaijan ,Goiter ,Adolescent ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Thyroid Gland ,Thyrotropin ,chemistry.chemical_element ,Iodine ,Iodide Peroxidase ,Thyroglobulin ,Endocrinology ,Internal medicine ,medicine ,Humans ,Child ,Autoantibodies ,Ultrasonography ,Palpation ,Triiodothyronine ,business.industry ,Thyroid ,Iodides ,medicine.disease ,Iodine deficiency ,Discontinuation ,Thyroxine ,medicine.anatomical_structure ,chemistry ,Female ,Thyroid function ,business - Abstract
The goal of this study was to assess the prevalence of iodine deficiency (ID) in Azerbaijan after the discontinuation of an iodine prophylaxis program by assessing the prevalence of goiter, iodine intake, and thyroid function. The study included 942 schoolchildren (475 boys and 467 girls) ages 8-14 years, from 13 distinct regions. The survey included the following: (1) clinical evaluation; (2) assessment of thyroid volume both by ultrasound and by palpation; (3) determination of iodide in a morning urine specimen using the classic Sandel-Kolthoff reaction in 347 schoolchildren; (4) determinations of thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4), thyroglobulin (Tg), and anti-thyroid peroxidase (TPO) in serum (n = 165) and TSH in whole blood spotted on filter paper (n = 942). The prevalence of goiter for the whole country was determined by ultrasound (US) to be 86% and by palpation 66%, reaching 100% in the mountainous regions of Caucasus. The median urinary iodine excretion (UIE) was 54 microg/L, reaching level of 26 and 39 microg/L in the Caucasus region. In conclusion, according to the World Health Organization (WHO) classification, Azerbaijan now has mild to moderate ID (median UIE, 54 microg/L) and in the mountainous regions with severe ID. The high prevalence of goiter and the low UIE emphasizes the need for urgent medical reintervention. An iodination program is now implemented by our team in the mountainous regions under the auspice of the government of Azerbaijan.
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- 2001
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17. Height Velocity and Skeletal Maturation in Elite Female Rhythmic Gymnasts
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Kostas B. Markou, Johannes C. A. Dimopoulos, Michel Leglise, Anastasia Theodoropoulou, Apostolos G. Vagenakis, George A. Vagenakis, Dan Benardot, and Neoklis A. Georgopoulos
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Adult ,Aging ,medicine.medical_specialty ,Percentile ,Adolescent ,Gymnastics ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Growth ,Biology ,Biochemistry ,Endocrinology ,Rhythm ,Animal science ,Internal medicine ,Genetic predisposition ,medicine ,Independent parameter ,Humans ,Prospective Studies ,Child ,Bone Development ,Puberty ,Biochemistry (medical) ,Final height ,Skeleton (computer programming) ,Body Height ,Skeletal maturation ,Body Composition ,Female ,Linear growth - Abstract
Rhythmic gymnasts performing under conditions of high intensity are exposed to particularly high levels of psychological stress and intense physical training, factors that can contribute to the observed delay in skeletal maturation and pubertal development, and alter optimal growth. The study was conducted in the field, during the International, European, and World Rhythmic Sports Gymnastics Championships of the years 1997-2000, and included 104 elite female rhythmic gymnasts, aged 12-23 yr. The study included height and weight measurements, estimation of body fat and skeletal maturation, and registration of parental height. Height, weight, target height, and predicted adult height were expressed as the SD score of the mean height and weight for age, according to Tanner's standards. Gymnasts were taller and thinner than average for age, with height velocity SD score for each age group above the 50th percentile for all age groups (n = 140, mean = 1.9 +/- 2.5). Interestingly, although height velocity in normal girls comes to an end by the age of 15, in our examined rhythmic gymnasts it continues up to the age of 18. There was a delay of skeletal maturation of 1.8 yr (n = 72, r = 0.730, P < 0.001), compensated by an acceleration of height velocity toward the end of puberty. The final adult height was identical to the estimated predicted height at first evaluation, and significantly higher than the genetically determined target height (n = 35, r = 0.58, P < 0.001), denoting that genetic predisposition to final height is not only achieved, but even exceeded. Using multiple regression analysis, target height was the only independent parameter that has been proven to influence positively the height velocity SD score (b = 0.233, t = 2.215, P = 0.029), denoting that genetic predisposition remains the main driving force for the observed efficient catch up growth. In conclusion, the elite rhythmic gymnasts compensate for their loss of pubertal growth spurt by a late acceleration of linear growth. Despite the delay in skeletal maturation, genetic predisposition of growth is not only preserved, but even exceeded.
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- 2001
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18. Dissociation of the Early Decline in Serum T3 Concentration and Serum IL-6 Rise and TNFα in Nonthyroidal Illness Syndrome Induced by Abdominal Surgery
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Apostolos G. Vagenakis, Fotios Kalfarentzos, Marina Michalaki, Venetsana Kyriazopoulou, and Maria Makri
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Adult ,Male ,medicine.medical_specialty ,Hydrocortisone ,Triiodothyronine, Reverse ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Deiodinase ,Thyrotropin ,Biochemistry ,Postoperative Complications ,Endocrinology ,Internal medicine ,Abdomen ,Blood plasma ,Humans ,Medicine ,Interleukin 6 ,Triiodothyronine ,biology ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,business.industry ,Biochemistry (medical) ,Thyroid ,Middle Aged ,Euthyroid Sick Syndromes ,Pathophysiology ,Thyroxine ,medicine.anatomical_structure ,Cytokine ,biology.protein ,Female ,business ,Abdominal surgery - Abstract
The etiology of the prompt decline in serum T3 in patients with nonthyroidal illness syndrome has not been adequately explained. It has been attributed to various parameters, including test artifacts, inhibitors of T4 and T3 binding to proteins, decreased 5′-deiodinase activity, and circulating cytokines. Currently, much attention is centered on the role of IL-6 and TNFα in developing the nonthyroidal illness syndrome through an effect on the hypothalamus, pituitary, and possibly 5′-deiodinase activity. We therefore studied the relation of the endogenous serum IL-6 and TNFα rise early in the course of nonthyroidal illness syndrome to the early decline in serum T3 in 19 apparently healthy individuals, aged 43 ± 16 yr, who underwent elective abdominal surgery for cholelithiasis or gastroplasty. Serum T3, free T3, T4, free T4, rT3, TSH, IL-6, and TNFα were measured before and at various time intervals up to 42 h after skin incision. We observed a prompt decline in serum T3 30 min before skin incision, which continued to decline throughout the observational period. The magnitude of the decline reached 20% from the baseline value at 2 h. The early decline of T3 was attenuated and lasted from the 2–8 h, probably due to the sharp increase in serum TSH that started immediately after the entrance to the operating room and lasted for 2 h. In contrast, serum T4 and free T4 concentrations were increased soon after skin incision and remained elevated during the first postoperative day. Serum rT3 increased approximately 6 h after the initiation of surgery and remained elevated thereafter. Serum IL-6 remained essentially undetectable for 2 h after skin incision, whereas serum T3 was low. Two hours after skin incision, serum IL-6 increased sharply and remained elevated throughout the observational period. Serum TNFα remained essentially undetectable throughout the postoperative period. Serum cortisol increased rapidly upon entrance to the operating room and remained elevated throughout the postoperative period. We conclude that the decline in serum T3 early in the course of nonthyroidal illness syndrome is not due to increased serum IL-6 or TNFα levels. The brisk TSH secretion soon after the onset of the syndrome attenuates the decline in serum T3 due to T3 secretion from the thyroid. The early and brisk cortisol response to surgery may at least in part explain the early decrease in serum T3 in nonthyroidal illness syndrome.
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- 2001
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19. Interleukin-6 and C-reactive protein as early markers of sepsis in patients with diabetic ketoacidosis or hyperosmosis
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Charalambos Gogos, A. G. Vagenakis, George Dimitracopoulos, H. P. Bassaris, Fotini Paliogianni, and S. Giali
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Adult ,Male ,medicine.medical_specialty ,Diabetic ketoacidosis ,Endocrinology, Diabetes and Metabolism ,Gastroenterology ,Diabetic Ketoacidosis ,Sepsis ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,Humans ,Medicine ,Interleukin 6 ,Aged ,Coma ,biology ,Interleukin-6 ,business.industry ,Osmolar Concentration ,Metabolic disorder ,C-reactive protein ,Middle Aged ,Prognosis ,medicine.disease ,Ketoacidosis ,C-Reactive Protein ,Endocrinology ,biology.protein ,Hyperglycemic Hyperosmolar Nonketotic Coma ,Female ,medicine.symptom ,business ,Biomarkers - Abstract
An early diagnosis of sepsis in patients with diabetic ketoacidosis and hyperosmolar non-ketotic coma is crucial and could save lives. We studied serum C-reactive protein and interleukin-6 to find out how useful these might be for identifying sepsis.Sixty one diabetic patients with ketoacidosis or hyperosmolar non-ketotic coma were enrolled. Patients with signs and symptoms of systemic inflammatory response syndrome were identified. Acute-phase reactants, including C-reactive protein and interleukin-6, the main cytokine responsible for the induction of acute-phase proteins, were measured on admission and when patients had clinically improved and were euglycaemic.A total of 49 out of 61 patients with diabetic ketoacidosis or hyperosmosis had signs of systemic inflammatory response syndrome. Another 27 patients had systemic inflammatory response syndrome and no signs of infection and 22 patients had systemic inflammatory response syndrome due to proven infection. We detected a significant increase in serum C-reactive protein and interleukin-6 values in patients infected compared with patients not infected with systemic inflammatory response syndrome SIRS. Patients who finally died had much higher levels of these proteins, while there was a prompt reduction of serum C-reactive protein and interleukin-6 early during remission.Diabetic ketoacidosis and hyperosmolar non-ketotic coma can often cause a clinical syndrome resembling systemic inflammatory response syndrome. Determination of serum C-reactive protein and interleukin-6 levels is a useful way of excluding an underlying infection early on as well as confirming and monitoring sepsis.
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- 2001
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20. Iodine-Induced Hypothyroidism
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Venetsana Kyriazopoulou, Apostolos G. Vagenakis, Neoklis A. Georgopoulos, and Kostas B. Markou
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endocrine system ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Thyroid Gland ,Amiodarone ,Autoimmune thyroiditis ,Endocrinology ,Hypothyroidism ,Pregnancy ,Thyroid peroxidase ,Prenatal Diagnosis ,Internal medicine ,medicine ,Humans ,Euthyroid ,biology ,Goiter ,business.industry ,Thyroid ,Infant, Newborn ,Drug Synergism ,Organification ,Iodides ,medicine.disease ,Thyroid Diseases ,medicine.anatomical_structure ,Postpartum thyroiditis ,biology.protein ,Female ,Thyroglobulin ,Thyroid function ,business ,Iodine - Abstract
Iodine is an essential element for thyroid hormone synthesis. The thyroid gland has the capacity and holds the machinery to handle the iodine efficiently when the availability of iodine becomes scarce, as well as when iodine is available in excessive quantities. The latter situation is handled by the thyroid by acutely inhibiting the organification of iodine, the so-called acute Wolff-Chaikoff effect, by a mechanism not well understood 52 years after the original description. It is proposed that iodopeptide(s) are formed that temporarily inhibit thyroid peroxidase (TPO) mRNA and protein synthesis and, therefore, thyroglobulin iodinations. The Wolff-Chaikoff effect is an effective means of rejecting the large quantities of iodide and therefore preventing the thyroid from synthesizing large quantities of thyroid hormones. The acute Wolff-Chaikoff effect lasts for few a days and then, through the so-called "escape" phenomenon, the organification of intrathyroidal iodide resumes and the normal synthesis of thyroxine (T4) and triiodothyronine (T3) returns. This is achieved by decreasing the intrathyroidal inorganic iodine concentration by down regulation of the sodium iodine symporter (NIS) and therefore permits the TPO-H202 system to resume normal activity. However, in a few apparently normal individuals, in newborns and fetuses, in some patients with chronic systemic diseases, euthyroid patients with autoimmune thyroiditis, and Graves' disease patients previously treated with radioimmunoassay (RAI), surgery or antithyroid drugs, the escape from the inhibitory effect of large doses of iodides is not achieved and clinical or subclinical hypothyroidism ensues. Iodide-induced hypothyroidism has also been observed in patients with a history of postpartum thyroiditis, in euthyroid patients after a previous episode of subacute thyroiditis, and in patients treated with recombinant interferon-alpha who developed transient thyroid dysfunction during interferon-a treatment. The hypothyroidism is transient and thyroid function returns to normal in 2 to 3 weeks after iodide withdrawal, but transient T4 replacement therapy may be required in some patients. The patients who develop transient iodine-induced hypothyroidism must be followed long term thereafter because many will develop permanent primary hypothyroidism.
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- 2001
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21. Increased sensitivity to the inhibitory effect of excess iodide on thyroid function in patients with beta-thalassemia major and iron overload and the subsequent development of hypothyroidism
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Theodore K. Alexandrides, Apostolos G. Vagenakis, Neoklis A. Georgopoulos, and S Yarmenitis
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Adult ,Male ,Thyroid Hormones ,endocrine system ,medicine.medical_specialty ,Iron Overload ,Adolescent ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Thyroid Gland ,Thyrotropin ,chemistry.chemical_element ,Thyroid Function Tests ,Iodine ,Endocrinology ,Hypothyroidism ,Liver Function Tests ,Thyroid peroxidase ,Internal medicine ,Humans ,Medicine ,Child ,Ultrasonography ,Subclinical infection ,biology ,business.industry ,Thyroid disease ,beta-Thalassemia ,Thyroid ,Primary hypothyroidism ,General Medicine ,Iodides ,medicine.disease ,medicine.anatomical_structure ,chemistry ,Child, Preschool ,Ferritins ,biology.protein ,Female ,Thyroid function ,business ,hormones, hormone substitutes, and hormone antagonists ,Follow-Up Studies ,Hormone - Abstract
OBJECTIVE: Patients with beta-thalassemia frequently develop primary hypothyroidism and other endocrine disorders due to iron overload. We studied whether administration of excess iodide to patients with apparently normal thyroid function could uncover an underlying thyroid disease. DESIGN AND METHODS: Twenty-five patients, 10 prepubertal (mean age 11+/-3 years) and 15 adults (mean age 23+/-5 years) with normal thyroid hormone and TSH levels, a normal response of TSH to TRH and negative thyroid peroxidase antibodies received 20mg iodide three times daily for three weeks, and thyroid hormone and TSH levels were measured weekly during, and for three weeks after, iodide administration and every 3 months thereafter for the next 5 years. RESULTS: During iodide administration there was a significant decrease in thyroid hormone concentrations which remained within normal levels, and a significant increase in TSH concentrations which in 14 out of 25 (56%) patients reached the hypothyroid level. Baseline TSH values were higher in those patients who developed subclinical hypothyroidism (2.31+/-0.71mU/l vs 1. 34+/-0.64mU/l, P=0.0016). Subclinical hypothyroidism developed in 70% of prepubertal and in 47% of adult patients. Serum ferritin was elevated in all patients. Nine of the fourteen patients (64.3%) who developed subclinical hypothyroidism during iodide administration developed hypothyroidism during the 5-year follow-up compared with only one of the eleven patients with a normal response to iodide (P=0.004). CONCLUSIONS: Patients with beta-thalassemia should not be exposed to excess iodide due to increased sensitivity to its inhibitory effects on thyroid function. The susceptible individuals frequently develop permanent hypothyroidism in the following years.
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- 2000
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22. Thyroid function and immune profile in rheumatoid arthritis. A controlled study
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A. G. Vagenakis, M. Makri, C. Markou, M. Christofidou, Vassiliki Siambi, and Andrew P. Andonopoulos
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Adult ,Male ,endocrine system ,medicine.medical_specialty ,endocrine system diseases ,Thyroid Gland ,Trab ,Thyroid Function Tests ,Gastroenterology ,Thyroid function tests ,Thyroiditis ,Arthritis, Rheumatoid ,Autoimmune thyroiditis ,Rheumatology ,Thyroid-stimulating hormone ,Monitoring, Immunologic ,Thyroid peroxidase ,Internal medicine ,Osteoarthritis ,medicine ,Humans ,Prospective Studies ,Aged ,biology ,medicine.diagnostic_test ,business.industry ,Penicillamine ,Thyroid ,General Medicine ,Middle Aged ,medicine.disease ,Thyroid Diseases ,Endocrinology ,medicine.anatomical_structure ,biology.protein ,Female ,Thyroid function ,business - Abstract
The aim of our study was to determine the prevalence of thyroid dysfunction and autoimmune abnormalities in rheumatoid arthritis (RA) and to further investigate the possible association between D-penicillamine and autoimmune thyroiditis. For this purpose, one hundred and one unselected consecutive patients with RA and 70 age and sex matched controls were studied prospectively. Evaluation included a complete history and physical examination with special attention to symptoms suggestive of thyroid pathology, routine laboratory and serologic immune profile, plus determination of serum levels of thyroxine (T4), triiodothyronine (T3), thyroid stimulating hormone (TSH), antibodies to thyroid peroxidase (AbTPO) and TSH receptor antibodies (TRAB). Serum thyroxine binding globulin (TBG) was measured in all subjects with high thyroid hormone levels, whereas free T3 and T4 concentrations were determined in all individuals with abnormal T3, T4, TSH or TBG. Six patients with hyperhyroidism, 3 with hypothyroidism and 1 with the euthyroid hyperthyroxinemia (EH) syndrome were found, whereas four of the controls had hyperthyroidism. Thirteen patients and 6 controls had high AbTPO levels whereas no one had high TRAB. No association was detected between thyroid abnormalities and any serologic RA finding. Furthermore, no correlation between thyroid dysfunction and elevated AbTPO's was found. A relatively high prevalence of thyroid dysfunction (9,9%) and subclinical autoimmune thyroiditis (12,9%), the latter indicated by elevated AbTPO's, was found in our RA patients. These figures were higher than those in the control group (5,7% and 8,6% respectively), but the difference did not reach statistical significance. Of further interest may be our finding that, despite anecdotal reports blaming D-penicillamine for cases of autoimmune thyroiditis, the incidence of the latter was similar among recipients and nonrecipients of the drug. Similarly, TRAB were not detected in any patient treated with D-penicillamine.
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- 1996
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23. Prolactin and Growth Hormone in Perinatal Asphyxia
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Anastasia Varvarigou, Constantinos Frimas, Maria Makri, Apostolos G. Vagenakis, and Nicholas G. Beratis
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endocrine system ,medicine.medical_specialty ,Encephalopathy ,Fetal Hypoxia ,Growth hormone ,Brain Ischemia ,Internal medicine ,medicine ,Humans ,Hypoxia, Brain ,Asphyxia ,Asphyxia Neonatorum ,Brain Diseases ,Fetus ,Respiratory distress ,business.industry ,Infant, Newborn ,Hypoxia (medical) ,medicine.disease ,Prolactin ,Perinatal asphyxia ,Endocrinology ,Growth Hormone ,Pediatrics, Perinatology and Child Health ,medicine.symptom ,business ,Infant, Premature ,hormones, hormone substitutes, and hormone antagonists ,Developmental Biology - Abstract
To assess the pituitary response to perinatal asphyxia, the prolactin (PRL) and growth hormone (hGH) serum concentrations were measured in 55 asphyctic (15 preterm and 40 full-term) and 35 control (15 preterm and 20 full-term) newborns at 2-4,24,48 and 96 h of life. At 2-4 h the median PRL in the preterm asphyctic neonates was 5.2 U/l, whereas in the preterm control newborns it was 3.2. In the full-term newborns with and without hypoxic-ischaemic encephalopathy (HIE) it was 5.8 and 3.4, respectively. In the full-term neonates with HIE the PRL remained significantly higher than in the controls up to the fourth day. At 2–4 h the median hGH in the preterm asphyctic and control newborns was 106.2 and 54.8 mU/l, respectively. In the full-term newborns it was 85.0 and 40.8, respectively. The lowest hGH concentrations were found in the severe HIE. The increased PRL and hGH in asphyxia may result from a stress-related hormone release, whereas the very low hGH concentrations in severe HIE may result from a damage at the hypothalamic-hypophyseal axis.
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- 1996
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24. Improved levothyroxine pharmacokinetics after bariatric surgery
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Georgios K. Markantes, Apostolos G. Vagenakis, Margarita I. Gkotsina, Fotios Kalfarentzos, George Sakellaropoulos, Kostas B. Markou, Irene Mamali, and Marina Michalaki
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Adult ,Male ,endocrine system ,Sleeve gastrectomy ,medicine.medical_specialty ,Thyroid Hormones ,Adolescent ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Levothyroxine ,Cmax ,Bariatric Surgery ,Endocrinology ,Pharmacokinetics ,Oral administration ,medicine ,Humans ,Obesity ,Biliopancreatic Diversion ,Gastrointestinal tract ,business.industry ,Area under the curve ,Middle Aged ,Surgery ,Thyroxine ,Treatment Outcome ,Female ,business ,medicine.drug - Abstract
The absorption of levothyroxine (LT4) is affected by many factors. Bariatric surgery is recommended in severely obese patients. The aim of this study was to determine the consequences of bariatric surgery on LT4 pharmacokinetic parameters, and to identify the regions of the gastrointestinal tract where LT4 is absorbed in patients with severe obesity before and after surgery.We studied 32 severely obese nonhypothyroid patients who underwent sleeve gastrectomy (SG; n=10), Roux-en-Y gastric bypass (RYGBP; n=7), or biliopancreatic diversion with long limbs (BPD-LL; n=15). Before surgery, from 8:00 a.m., blood samples were collected before and every 30 minutes after the oral administration of a solution of 600 μg of LT4. The same procedure was repeated 35 days after surgery. We estimated the pharmacokinetic parameters of LT4 before and after surgery, including the area under the curve (AUC), the peak thyroxine concentration (Cmax), and the time to peak thyroxine concentration (Tmax).Following surgery, in the SG group, the mean AUC was higher than it was before surgery (18.97±6.01 vs. 25.048±6.47 [μg/dL]·h; p0.01), whereas the values of Cmax and Tmax were similar to those before surgery. In the RYGBP group, mean AUC, Cmax, and Tmax were similar before and after surgery. In the BPD-LL group, mean AUC and Cmax were higher after surgery than before (14.18±5.64 vs. 25.51±9.1 [μg/dL]·h, p0.001; 5.62±1.34 vs. 8.16±2.57 μg/dL, p0.001, respectively), whereas Tmax was similar.The pharmacokinetic parameters of LT4 absorption are improved following SG and BPD-LL types of bariatric procedures. We conclude that the stomach, the duodenum, and the upper part of the jejunum are not sites for LT4 absorption, because in the above-mentioned bariatric procedures these are bypassed or removed.
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- 2012
25. Hyperinsulinaemia in Syndrome X: A Marker of the Syndrome?
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Dimitrios Alexopoulos, Dennis V. Cokkinos, Apostolus G. Vagenakis, Vasiliki Asimakopoulou, Christoforos Olympios, John Christodoulou, Stefanos G. Foussas, Venetsiana Kiriazopoulou, and Agathoklis Psiroyiannis
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Blood Glucose ,Male ,medicine.medical_specialty ,Epidemiology ,business.industry ,Insulin ,medicine.medical_treatment ,Middle Aged ,medicine.disease ,Angina ,Pathogenesis ,Coronary artery disease ,Endocrinology ,Internal medicine ,medicine ,Humans ,Female ,Abnormality ,Cardiology and Cardiovascular Medicine ,business ,Hyperinsulinism ,Syndrome x ,Body mass index ,Microvascular Angina - Abstract
BACKGROUND: Stimulated hyperinsulinaemia is observed in some patients with syndrome X, defined as angina, positive stress test and normal coronary arteriography, and may be involved in the pathogenesis of the syndrome. An increased sympathetic response to exercise may also be pathogenetically involved. However, the diagnostic value of hyperinsulinaemia as a marker of this syndrome has not been defined. METHODS: We determined blood glucose and immunoreactive insulin during fasting, at 60 and 120 min after a glucose load of 75g in 21 patients (eight men, 13 women, 53.9 +/- 7.1 years old) with syndrome X and in 21 healthy volunteers matched to the patients for age, sex and body mass index (eight men, 13 women, 51.6 +/- 9.3 years old). Insulin values were related to the rate-pressure product increase at first exercise stage. RESULTS: The glucose values as well as the insulin values during fasting were similar in syndrome X patients and in controls. However, significantly higher insulin values (mU/l) were observed at 60 (P < 0.01) and 120 min (P < 0.005) in syndrome X patients (median 75.5 and 52, range 43-290 and 6.1-212, respectively) than in controls (median 47.5 and 24.5, range 8-195.6 and 5.2-164, respectively). A considerable overlap of insulin values, however, was observed between the two groups, with abnormal values even during fasting. For a specificity of 95%, an abnormal insulin value had a sensitivity of between 19 and 24% and a diagnostic accuracy of 57-60%. A significant positive correlation was found between insulin levels after the glucose load and the rate-pressure product increment with exercise (60 min, r = 0.60; 120 min, r = 0.65). CONCLUSION: Hyperinsulinaemia may be pathogenetically involved in syndrome X patients, in close relation to the higher sympathetic drive that characterizes this syndrome. However, the wide range of insulin values, frequently overlapping with normal values, limits the usefulness of this abnormality as a marker of the syndrome.
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- 1994
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26. The expression of omental 11β-HSD1 is not increased in severely obese women with metabolic syndrome
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Georgia Voukelatou, Fotis Kalfarentzos, Marina Michalaki, Vasiliki Koika, Athanasios Tsoukas, Athanasios G. Papavassiliou, Venetsana Kyriazopoulou, Anna G. Antonacopoulou, Apostolos G. Vagenakis, and Marinos Nikolaou
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Adult ,medicine.medical_specialty ,Health (social science) ,Intra-Abdominal Fat ,Hydrocortisone ,medicine.medical_treatment ,Biopsy ,Subcutaneous Fat ,Bariatric Surgery ,Hysterectomy ,Real-Time Polymerase Chain Reaction ,Young Adult ,Glucocorticoid receptor ,Receptors, Glucocorticoid ,Physiology (medical) ,Internal medicine ,11-beta-Hydroxysteroid Dehydrogenase Type 1 ,Medicine ,Humans ,RNA, Messenger ,Metabolic Syndrome ,Analysis of Variance ,medicine.diagnostic_test ,business.industry ,Middle Aged ,medicine.disease ,Obesity ,Obesity, Morbid ,Hypercortisolemia ,Endocrinology ,Female ,Metabolic syndrome ,business ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Objective: Plasma cortisol in obese subjects does not differ from that in normoweight subjects. Extra-adrenal cortisol production by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) can result in local hypercortisolemia. The aim of the present study was to examine the role of visceral hypercortisolemia in the development of metabolic syndrome in severe obesity. Methods: Eight lean women during hysterectomy (controls) and 19 severely obese women during bariatric surgery were studied, 8 without metabolic syndrome (OM– group) and 11 with it (OM+ group). Biopsies of omental and subcutaneous fat were performed in the severely obese women during surgery, but only omental biopsies in the controls. Expression of 11β-HSD1, glucocorticoid receptor α (GRα) and glucocorticoid receptor β (GRβ) was evaluated using real-time PCR.Results: Omental 11β-HSD1 expression was different between groups (one-way ANOVA, p < 0.01). Post-hoc analysis revealed that mean omental 11β-HSD1 mRNA levels were higher in the OM– group compared to controls, whereas they were similar when comparing the OM+ group with lean controls. Expression of 11β-HSD1 in subcutaneous fat was not different between OM+ and OM– groups. GRα expression in omental fat did not differ among groups or between omental and subcutaneous fat in severely obese patients. An expression of GRβ was not detected.Conclusion: Contrary to our original hypothesis, omental 11β-HSD1 expression is not increased in the OM+ group.
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- 2011
27. Dissociation of thyrotropin and leptin secretion in acute surgical stress in severely obese patients
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Venetsana Kyriazopoulou, Apostolos G. Vagenakis, Marianna Argentou, Fotis Kalfarentzos, Panagiotis Mylonas, and Marina Michalaki
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Adult ,Leptin ,Male ,endocrine system ,medicine.medical_specialty ,Surgical stress ,Time Factors ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Bariatric Surgery ,Thyrotropin ,In vivo ,Internal medicine ,Medicine ,Humans ,Secretion ,Circadian rhythm ,Nutrition and Dietetics ,business.industry ,digestive, oral, and skin physiology ,Thyroid ,Fasting ,medicine.disease ,Obesity ,Euthyroid Sick Syndromes ,Circadian Rhythm ,Obesity, Morbid ,Endocrinology ,medicine.anatomical_structure ,Surgery ,business ,hormones, hormone substitutes, and hormone antagonists ,Hormone - Abstract
During illness, thyroid parameters undergo acute changes, which are known as non-thyroidal illness syndrome, the cause of which has not been elucidated. In vitro and in vivo data demonstrate that leptin regulates the expression of thyrotropin-releasing hormone (TRH)-mRNA in the paraventricular nucleus as well as the secretion of thyrotropin (TSH) in response to fasting in humans and animals. Moreover, in healthy adults, TSH and leptin have almost identical circadian rhythms. Our aim was to investigate the secretion of leptin and TSH, and their probable interaction, during the acute stress that is induced by surgery.We studied 18 severely obese but otherwise healthy men. All participants were admitted to the hospital in the morning after an overnight fast. On the following day, 14 of the participants underwent bariatric surgery at 0900. The remaining four participants did not undergo surgery and served as controls. Serum samples to measure the levels of TSH and leptin were collected from all participants, as follows: upon admission to the hospital (baseline values) and on the following day at 0900 and every 10 min, thereafter for 9 h.The serum TSH increased during the first hour after skin incision (si) and then decreased gradually throughout the rest of the observation period. In contrast, during the first hour after si, the leptin levels remained unaltered. The leptin levels then decreased and reached a nadir at 4 h and 10 min post si after which they remained constant for approximately 1 h. Thereafter, while TSH continued to decrease, leptin started to increase and reached baseline values at 9 h post si. In control subjects, the TSH and leptin profiles seemed parallel each other.During acute surgical stress, the secretion of TSH and leptin in severely obese men is asynchronous and causality could not be proven.
- Published
- 2009
28. Treating iodine deficiency: long-term effects of iodine repletion on growth and pubertal development in school-age children
- Author
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Apostolos G. Vagenakis, Rauf Jabarov, Barbara Vlassopoulou, Eleni Anastasiou, George A. Vagenakis, Evgenia Lampropoulou, Loredana Rottstein, Kostas B. Markou, Neoklis A. Georgopoulos, Athanasios Tsekouras, Anastasia Theodoropoulou, Charalampos Vasilopoulos, Panagiotis Mylonas, Dimitris J. Apostolopoulos, and Eftychia Koukkou
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Male ,Pediatrics ,medicine.medical_specialty ,Time Factors ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Human Development ,Treatment outcome ,chemistry.chemical_element ,Iodine ,Endocrinology ,Internal medicine ,medicine ,Prevalence ,Humans ,Child ,Growth Disorders ,School age child ,business.industry ,Goiter ,Puberty ,medicine.disease ,Iodine deficiency ,Thyroid Diseases ,Body Height ,Treatment Outcome ,chemistry ,Female ,business ,Oils - Abstract
Iodine deficiency (ID) is still a major universal health problem. Iodine deficiency disorders (IDDs) affect people of all ages, among whom the most vulnerable are children and adolescents. The aim of the present study was to assess the long-term effects on growth and pubertal development of correcting severe ID in areas of Azerbaijan between 1999 and 2000.Iodized oil was administered orally to 293,000 children, aged 6-16 years. Among those, 364 children were randomly selected and were examined 1 year before the administration of iodized oil (Group I-neg, iodine negative) and 295 children (Group I-Rx, iodine treated) were examined 4 years (Group I-R x 4, iodine treated 4 years later; n = 173) or 5 years (Group I-R x 5, iodine treated 5 years later; n = 122) after the last dose of iodide.In Group I-neg the median urine iodine concentration (UIC) (mcg/L) was 36 (mean: 36.272 +/- 11.036) and increased significantly (p0.001) in Group I-R x 4: 188 (mean: 230.969 +/- 155.818) and in Group I-R x 5: 175 (mean: 201.176 +/- 130.369). The prevalence of goiter was 99% in Group I-neg and 2% in Group I-R x 4. Children in Group I-Rx had a greater standard deviation score (SDS) for height (-0.1364 +/- 1.279, n = 294) than children in Group I-neg (-0.5019 +/- 1.17, n = 363) (p0.001, t = -3.817), which was more significant for boys. SDS for weight was similar in both groups (Group I-neg: -0.17 +/- 0.78, n = 363; Group I-Rx: -0.115 +/- 0.917, n = 294). The rate of puberty development as judged by the development of breast and pubic hair was normalized in both sexes after the correction of ID.Our results demonstrate that long-term correction of severe ID leads to sustained improvement of linear growth accompanied by a normalization of the time of onset of pubertal development for both sexes.
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- 2008
29. Effects of Iodides: Clinical Studies
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Apostolos G. Vagenakis
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Pathology ,medicine.medical_specialty ,business.industry ,Endocrinology, Diabetes and Metabolism ,Thyroid ,Thyroid Gland ,History, 20th Century ,Iodides ,Bioinformatics ,Thyroid Diseases ,United States ,Endocrinology ,medicine.anatomical_structure ,medicine ,Animals ,Homeostasis ,Humans ,business - Published
- 1990
- Full Text
- View/download PDF
30. Thyroid hormone synthesis and secretion in humans after 80 milligrams of iodine for 15 days and subsequent withdrawal
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Anastasia Theodoropoulou, Maria Makri, Apostolos G. Vagenakis, and Kostas B. Markou
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medicine.medical_specialty ,Wolff–Chaikoff effect ,Thyroid Hormones ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,chemistry.chemical_element ,Thyrotropin ,Context (language use) ,Excessive iodine intake ,Iodine ,Biochemistry ,Endocrinology ,Internal medicine ,medicine ,Humans ,Euthyroid ,Hyperparathyroidism ,business.industry ,Biochemistry (medical) ,Thyroid ,medicine.disease ,Thyroxine ,medicine.anatomical_structure ,chemistry ,Triiodothyronine ,business ,Hormone - Abstract
Context: In animals, acute iodine administration results in acute intrathyroidal inhibition of iodinations followed by escape of the inhibition if the excessive iodine intake continues. In humans, the intrathyroidal nonhormonal and hormonal iodine concentration after exposure to large doses of iodine for a relatively long period of time is not known. Objective: To determine whether, in human thyroid, administration of large doses of iodine for a relatively long time results in alterations of intrathyroidal hormonal (HI) T4 and T3 and total iodine (TI) content, as well as whether changes in serum concentration of thyroid hormones and TSH would occur after iodine administration or discontinuation. Design: In 33 euthyroid patients with single thyroid nodule or hyperparathyroidism, Lugol solution (80 mg iodine) was administered for 15 d before operation. Groups of six to eight patients underwent operation 0, 5, 10, and 15 d after iodine withdrawal. TI, HI in a sample of thyroid tissue, and serum concentration of T4, T3, and TSH were measured. In 21 normal euthyroid subjects who did not undergo operation, a similar protocol was used and serial blood measurements were taken. Main Outcome Measure: Intrathyroidal TI, HI, and serum thyroid hormone and TSH measurements were the main outcome measure. Results: Intrathyroidal HI content and serum T4 and T3 were unchanged during and after iodine discontinuation. TI was increased during iodine administration and returned to control values 5 d after discontinuation of iodine. The ratio of HI/TI was decreased and returned to control values 15 d after the iodine was discontinued. Serum TSH was increased during iodine administration and returned to control values 10 d after iodine withdrawal. Conclusions: In humans, administration of iodine for a relatively long period of time was accompanied by increased intrathyroidal TI, but no changes in HI or demonstrable increases of serum T4 and T3 were observed. It is hypothesized that the maintenance of normal intrathyroidal HI is the result of the combined inhibitory effect of iodine on thyroid hormone synthesis and on the release of T4 and T3 from the thyroid.
- Published
- 2006
31. The role of Hemochromatosis C282Y and H63D mutations in the development of type 2 diabetes mellitus in Greece
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Apostolos G. Vagenakis, Athanasios G. Papavassiliou, A Psilopanagiotou, Ioannis Habeos, Venetsana Kyriazopoulou, and Agathoklis Psyrogiannis
- Subjects
medicine.medical_specialty ,education.field_of_study ,Transferrin saturation ,business.industry ,Endocrinology, Diabetes and Metabolism ,Population ,Type 2 Diabetes Mellitus ,General Medicine ,medicine.disease ,Endocrinology ,Internal medicine ,Diabetes mellitus ,Hereditary hemochromatosis ,medicine ,Risk factor ,business ,education ,Allele frequency ,Hemochromatosis - Abstract
Several authors have suggested a positive association between diabetes type 2 (DM2) and the C282Y and H63D mutations of the hereditary hemochromatosis gene but others have disputed it. There are also papers reporting an increased iron load in diabetes type 2 and a possible association with the pathogenesis of the disease. We therefore performed a study in 100 type 2 diabetics and 100 age and sex matched controls to assess the possibility that C282Y and H63D mutations constitute a risk factor for DM2 in Greece. We also evaluated the iron load in 500 diabetes type 2 patients and 423 age and sex matched controls. We did not find any differences in the allele frequencies of the above mutations between patients with diabetes type 2 and controls. The allele frequencies were estimated to be 0.0075 for the C282Y and 0.115 for the H63D mutation. Subjects with even one mutation (C282Y or H63D) had higher transferrin saturation compared to those with no such mutations. This seems to apply to both diabetics (49+/- 8,6 vs 44,5+/- 5,4, p
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- 2006
32. Growth, pubertal development, skeletal maturation and bone mass acquisition in athletes
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Anastasia Theodoropoulou, Apostolos G. Vagenakis, Kostas B. Markou, Panagiotis Mylonas, George A. Vagenakis, and Neoklis A. Georgopoulos
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medicine.medical_specialty ,biology ,Bone density ,Athletes ,business.industry ,Endocrinology, Diabetes and Metabolism ,Bone age ,General Medicine ,medicine.disease ,biology.organism_classification ,Osteopenia ,Endocrinology ,Internal medicine ,Prepubertal stage ,medicine ,Menarche ,Genetic predisposition ,business ,Balance (ability) - Abstract
The genetic potentials for growth can be fully expressed only under favourable environmental conditions. Excessive physical training may negatively affect growth, especially during puberty. Sports that require a strict control of energy input in the presence of a high energy output are of particular concern. In gymnastics, a different pattern in skeletal maturation was observed, leading to an attenuation of growth potential ins Artistic Gymnasts (AG), more pronounced in males than in females, whereas in female Rhythmic Gymnasts (RG) the genetic predisposition to growth was preserved because of a late catch-up growth phenomenon. In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented. Intensive physical training and negative energy balance modify the hypothalamic pituitary set point at puberty, prolong the prepubertal stage and delay pubertal development and menarche in a variety of sports. In elite RG and AG the prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, paralleling the bone age rather than the chronological age. Bone formation, and, consequently, BMD are enhanced by physical activity. In athletes, high-impact loading activities have been shown to improve BMD, while in sports requiring a lean somatotype, the delay in skeletal maturation and pubertal development, resulting from hypoestrogenemia, predisposes athletes to osteopenia. In AG, an increase in bone density is observed using the bone age as denominator.
- Published
- 2006
33. Prolactin, cortisol secretion and thyroid function in patients with stroke of mild severity
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Venetsana Kyriazopoulou, N. Lekka, J. Elloul, P. Taleli, Anastasia Theodoropoulou, A. G. Vagenakis, and I. C. Metallinos
- Subjects
Cortisol secretion ,Male ,endocrine system ,medicine.medical_specialty ,Time Factors ,endocrine system diseases ,Hydrocortisone ,Endocrinology, Diabetes and Metabolism ,media_common.quotation_subject ,Clinical Biochemistry ,Thyrotropin ,Thyroid Function Tests ,Biochemistry ,Thyroid function tests ,Endocrinology ,TRH stimulation test ,Patient Admission ,Internal medicine ,medicine ,Post-stroke depression ,Humans ,Euthyroid ,Stroke ,Thyrotropin-Releasing Hormone ,media_common ,Aged ,Depressive Disorder ,medicine.diagnostic_test ,business.industry ,Convalescence ,Biochemistry (medical) ,General Medicine ,Middle Aged ,medicine.disease ,Prolactin ,Female ,Thyroid function ,business ,hormones, hormone substitutes, and hormone antagonists - Abstract
Different attempts were made to identify the variables that may be involved in the clinical course of cerebrovascular ischemia. In the case of stroke with mild severity (SMS), the clinical significance of neuroendocrine changes as well as of post-stroke depression (PSD) remains unknown. We therefore evaluated the presence of neuroendocrine changes in the acute and post-acute phase of SMS, and their potential role during convalescence. Serum cortisol, T4, T3, FT4, FT3, TSH and PRL levels were measured in 17 euthyroid patients with stroke on admission (day 1), following morning (day 2), 7 days and 3 months later. TSH and PRL secretion after TRH test were measured. Stroke severity on admission was determined by Scandinavian Stroke Scale (SSS). Montgomery-Asberg Depression Rating Scale (Madrs) was used for assessment of post-stroke depression. On admission, TSH and T3, were within normal limits and were greater compared to values on day 2. Lower basal TSH and decreased TSH response to TRH on day 2, were associated with stroke of greater severity. Delta-PRL after TRH on day 2 was higher in patients who develop PSD. Changes in serum thyroid hormones in SMS, reflects those of non-thyroidal illness. A mild stimulation of hypothalamic-pituitary-adrenal axis was detected. We provide evidence that PRL response to TRH, in the acute phase of stroke may be used as an index for early detection of PSD.
- Published
- 2006
34. Delayed but normally progressed puberty is more pronounced in artistic compared with rhythmic elite gymnasts due to the intensity of training
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Anastasia Theodoropoulou, George A. Vagenakis, Apostolos G. Vagenakis, G Kourounis, Dan Benardot, Neoklis A. Georgopoulos, Kostas B. Markou, and Michel Leglise
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Delayed puberty ,Adult ,medicine.medical_specialty ,Adolescent ,Gymnastics ,Endocrinology, Diabetes and Metabolism ,education ,Clinical Biochemistry ,Context (language use) ,Biochemistry ,Pubarche ,Pubertal stage ,Endocrinology ,Internal medicine ,medicine ,Sexual maturity ,Humans ,Sexual Maturation ,Thelarche ,Child ,Menarche ,Puberty, Delayed ,Physical Education and Training ,business.industry ,Biochemistry (medical) ,Bone age ,Cross-Sectional Studies ,Regression Analysis ,Female ,medicine.symptom ,business - Abstract
Elite gymnasts are subjected to intense training, which may alter pubertal development.The objective of the investigation was to study the impact of gymnastics on pubertal development in rhythmic (RGs) and artistic gymnasts (AGs).Evaluation of somatometric parameters, pubertal stage, and intensity of training in the competition field were studied.The study was conducted at European and world championships of years 1997-2004.Subjects included 433 elite RGs and 427 AGs, aged 11-23 yr.There were no interventions.Mean chronological and bone ages of each pubertal stage and their relation to the intensity of training were measured.AGs and RGs showed a delay in skeletal maturation (Delta age-bone age, 2.13 and 1.28, respectively; P0.001). AGs were subjected to higher levels of physical training. Thelarche occurred at 12.9 yr for RGs and 13.2 yr for AGs (P = 0.003) and pubarche at 12.5 and 12.9 yr, respectively (P = 0.002). Puberty was delayed but normally progressed. AGs entered each pubertal stage later than RGs. The delay was influenced by the amount of energy output. Menarcheal age was 14.6 yr for RGs and 14.9 yr for AGs. Menarche was influenced in AGs by bone age (b = 0.333; t = 2.521; P = 0.020), pubarche (b = 0.322; t = 2.401; P = 0.026), and body fat (b = -0.458; t = -3.412; P = 0.003) and in RGs by bone age (b = 0.378; t = 3.689; P0.001) and pubarche (b = 0.525; t = 6.017; P0.001).In RGs and AGs, pubertal development was shifted to a later age, maintaining a normal rate of progression, which followed the bone age. AGs, who were exposed to a greater and more sustained energy output than RGs, presented a more pronounced delay in both skeletal maturation and pubertal development.
- Published
- 2005
35. Function of the hypothalamic-pituitary-gonadal axis in long-term survivors of hematopoietic stem cell transplantation for hematological diseases
- Author
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Christos Smias, Apostolos G. Vagenakis, David Rousso, Ioanna Sakellari, Vassilios Mpatakoias, A. Avramides, Panayotis Kaloyannidis, Achilleas Anagnostopoulos, Dimitrios Panidis, Maria Somali, and Anargyros Kourtis
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Transplantation Conditioning ,Hormone Replacement Therapy ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Hypothalamus ,Physiology ,Graft vs Host Disease ,Hypothalamic–pituitary–gonadal axis ,Gonadotropin-releasing hormone ,Hematopoietic stem cell transplantation ,Transplantation, Autologous ,Gonadotropin-Releasing Hormone ,Endocrinology ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Hormone replacement therapy (male-to-female) ,Humans ,Testosterone ,Survivors ,Gonads ,Infertility, Male ,Leydig cell ,business.industry ,Estrogen Replacement Therapy ,Gonadal Disorders ,Hematopoietic Stem Cell Transplantation ,Obstetrics and Gynecology ,Total body irradiation ,Luteinizing Hormone ,Transplantation ,medicine.anatomical_structure ,Hematologic Neoplasms ,Pituitary Gland ,Female ,Follicle Stimulating Hormone ,business - Abstract
Gonadal dysfunction in adult long-term survivors of hematopoietic stem cell transplantation (HSCT) is an adverse effect of conditioning regimens consisting of chemotherapy and total body irradiation (TBI). The impact of conditioning regimens consisting of chemotherapy alone on the function of the hypothalamic-pituitary-gonadal (HPG) axis was evaluated in a series of 41 female and 31 male patients who had undergone either autologous or allogeneic bone marrow/peripheral blood stem cell transplantation; mean age at transplantation was 32.6 years and mean time interval from transplantation was 1.5 years (range 0.2-9.8 years). Provocative testing of the HPG axis by administration of luteinizing hormone-releasing hormone was included in the first endocrinological evaluation. The follow-up period extended to three consecutive years. Gonadal dysfunction was not reported by any of the patients prior to their underlying illness. Hypergonadotrophic hypogonadism was observed in 97% of female and 19% of male patients. Leydig cell strain (normal testosterone, high luteinizing hormone levels) was evident in 32% and spermatogenesis damage (high follicle-stimulating hormone levels) in 68% of the male population. At the conclusion of the study four women (10%) had regained spontaneous menses and all hypogonadal men had resumed normal testosterone levels. Our results indicate a high incidence of gonadal dysfunction due to target organ failure in HSCT recipients not treated by TBI.
- Published
- 2005
36. Insulin sensitivity and fibrinogen concentrations in normoglycaemic offspring of Type 2 diabetic parents
- Author
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Anastasia Theodoropoulou, Agathoklis Psyrogiannis, Marina Michalaki, Apostolos G. Vagenakis, Venetsana Kyriazopoulou, and Ioannis Habeos
- Subjects
Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,business.industry ,Offspring ,Endocrinology, Diabetes and Metabolism ,Insulin sensitivity ,Fibrinogen ,Glucose Tolerance Test ,Middle Aged ,Endocrinology ,Diabetes Mellitus, Type 2 ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Insulin ,Female ,business ,medicine.drug - Published
- 2005
37. Adequacy of saliva 17-hydroxyprogesterone determination using various collection methods
- Author
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Michel Leglise, Neoklis A. Georgopoulos, Kostas B. Markou, Panagiotis Mylonas, Apostolos G. Vagenakis, Anastasia Theodoropoulou, and Maria Makri
- Subjects
Adult ,Male ,Saliva ,Clinical Biochemistry ,Radioimmunoassay ,Biochemistry ,law.invention ,Specimen Handling ,Cushing syndrome ,Endocrinology ,Saliva collection ,law ,medicine ,Humans ,Molecular Biology ,Collection methods ,Pharmacology ,Chromatography ,Chemistry ,17-alpha-Hydroxyprogesterone ,Organic Chemistry ,Healthy subjects ,medicine.disease ,Hydroxyprogesterone ,Cotton swab ,Female - Abstract
Steroids determination in saliva offers several advantages. The collection of saliva is a noninvasive, less stressful technique than blood withdrawal and reflects the circulating unbound fractions. The suitability of saliva for 17-hydroxyprogesterone and cortisol determinations has been documented in healthy subjects as well as in diseases like Congenital Adrenal Hyperplasia and Cushing syndrome. The aim of the study was to compare the influence of different collection methods on the results of 17-hydroxyprogesterone measurement in saliva collected by different ways, using commercially available RIAs developed for plasma. 17-hydroxyprogesterone was determined in 64 healthy adult volunteers (30 males, 34 females) in serum (Group SE) and in saliva collected before meals at 8-10 p.m. by directly spitting into a plastic tube (Group SP), using a cotton swab (Group SA) and using a polyester swab Salivette (Group SB). We used a commercially available direct radioimmunoassay without separation technique. The 17-hydroxyprogesterone mean values (ng/ml) were 1.16+/-1.3 (Group SE), 0.056+/-0.046 (Group SP), 0.089+/-0.048 (Group SA) and 0.058+/-0.049 (Group SB). The detection limit was 0.010 ng/ml. The correlations between the values in serum (Group SE) and in saliva were: r=0.77, p0.05 (Group SP); r=0.62, p0.05 (Group SA); r=0.70, p0.05 (Group SB). The saliva values corresponding to the serum cut-off point of 3 ng/ml upper limit of normal values were in ng/ml 0.13 (Group SP), 0.16 (Group SA) and 0.11 (Group SB). In conclusion, 17-hydroxyprogesterone determinations in saliva using commercially available RIAs primarily developed for serum, is a reliable and easy to perform procedure. The three different methods of saliva collection showed 17-hydroxyprogesterone concentrations to have good agreement.
- Published
- 2005
38. Growth and skeletal maturation in male and female artistic gymnasts
- Author
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Apostolos G. Vagenakis, Kostas B. Markou, Michel Leglise, Neoklis A. Georgopoulos, and Anastasia Theodoropoulou
- Subjects
Adult ,Male ,medicine.medical_specialty ,Bone development ,Adolescent ,Gymnastics ,Body height ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Growth ,Body weight ,Biochemistry ,Body Mass Index ,Endocrinology ,Sex Factors ,Sex factors ,Internal medicine ,medicine ,Humans ,Bone Development ,business.industry ,Biochemistry (medical) ,Final height ,Body Weight ,Puberty ,Bone age ,Body Height ,Skeletal maturation ,Regression Analysis ,Female ,business ,Body mass index - Abstract
We studied 262 athletes who were 13-23 yr old. There were 93 male and 169 female artistic gymnasts (AG). This study is unique in character, because all variables were measured on the field of competition (24th European Championship). Male AG had a higher height SD score than female (P < 0.001), with a higher reported target height SD score (P < 0.001), a higher predicted final height (P = 0.007), a lower Delta height - target height (P < 0.001), a less delayed bone age (P < 0.001), a greater body mass index (BMI) (P < 0.001), a lower mean body fat (P
- Published
- 2004
39. The influence of intensive physical exercise on bone acquisition in adolescent elite female and male artistic gymnasts
- Author
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Apostolos Kontogiannis, Michel Leglise, Panagiotis Mylonas, Anastasia Theodoropoulou, Kostas B. Markou, Neoklis A. Georgopoulos, and Apostolos G. Vagenakis
- Subjects
Adult ,Male ,medicine.medical_specialty ,Bone density ,Adolescent ,Gymnastics ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Physical exercise ,Biochemistry ,Endocrinology ,Sex Factors ,Bone Density ,Internal medicine ,medicine ,Humans ,Exercise ,Bone mineral ,Growth chart ,Bone Development ,business.industry ,Biochemistry (medical) ,Body Weight ,Puberty ,Bone age ,Body Height ,Physical therapy ,Lean body mass ,Regression Analysis ,Female ,Age of onset ,business ,Body mass index - Abstract
Physical exercise enhances bone acquisition during adolescence. The aim of the study was to evaluate the influence of intensive physical exercise on bone acquisition in adolescent elite artistic gymnasts. The study included 262 athletes (93 males and 169 females, aged 13-23 yr) participating in the 24th European Championship held in Greece. Bone age compared with chronological age was delayed by 2 yr for females (n = 120) and 1 yr for males (n = 68). For both sexes, the growth chart of bone mineral density (BMD) followed a normal pattern when estimated according to bone age rather than chronological age. For females, BMD was positively correlated with bone age, chronological age, height, body weight, body mass index, body fat, lean body mass, and with age of onset of training, and negatively with duration of exercise and intensity of training (P values range from0.05 to0.0001). Multiple regression analysis revealed that age of onset of training was the major parameter attenuating the effect of exercise on BMD (P0.001). The latter was related to the stage of puberty (P0.05). For males, BMD was correlated positively with bone age, height, body weight, and lean body mass (P values range from0.01 to 0.0001). Multiple regression analysis revealed that the more powerful factor influencing BMD was weight (P0.01). In conclusion, bone acquisition in adolescents under intensive physical training follows the normal pattern only when estimated according to bone age. The age of onset, the duration, and the intensity of exercise attenuate the bone acquisition, at least in female artistic gymnasts.
- Published
- 2004
40. Autonomously functioning thyroid nodules in a former iodine-deficient area commonly harbor gain-of-function mutations in the thyrotropin signaling pathway
- Author
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Athanasios G. Papavassiliou, Apostolos G. Vagenakis, Adamantia Papachatzopoulou, Argyro Sgourou, Neoklis A. Georgopoulos, Gerasimos P. Sykiotis, Kostas B. Markou, and Venetsana Kyriazopoulou
- Subjects
Thyroid nodules ,Adenoma ,Adult ,Male ,endocrine system ,Pathology ,medicine.medical_specialty ,endocrine system diseases ,Endemic Diseases ,Somatic cell ,Endocrinology, Diabetes and Metabolism ,Population ,Thyrotropin ,Biology ,medicine.disease_cause ,Pathogenesis ,Endocrinology ,Internal medicine ,medicine ,Humans ,Thyroid Nodule ,Mutation frequency ,education ,Aged ,education.field_of_study ,Mutation ,Hyperplasia ,Greece ,Thyroid ,Receptors, Thyrotropin ,General Medicine ,Middle Aged ,medicine.disease ,Iodine deficiency ,Heterotrimeric GTP-Binding Proteins ,medicine.anatomical_structure ,Thyroidectomy ,Female ,Goiter, Nodular ,Iodine ,Signal Transduction - Abstract
BACKGROUND: Somatic activating mutations of the thyrotropin (thyroid-stimulating hormone (TSH)) receptor (TSHR) and G(alphas) protein have been detected in solitary toxic adenomas and toxic multinodular goiters, but their role in the pathogenesis of autonomous nodules is debated. The frequency of mutations is highly variable among populations and is inversely proportional to iodine intake. DESIGN AND PATIENTS: We screened 28 clinically and histologically heterogeneous autonomous nodules from 24 Greek patients for the presence of TSHR and G(alphas) mutations. RESULTS: By direct sequencing of genomic DNA, we detected 11 somatic heterozygous gain-of-function mutations in TSHR and one in G(alphas). Forty-three percent (12 of 28) of all nodules and 57% (four of seven) of solitary toxic adenomas harbored an activating mutation. Typical adenomas and hyperplastic nodules did not differ in mutation frequency. Substitutions I568T and T632I were detected in both histological types of nodules. CONCLUSIONS: Our findings indicate that activating somatic mutations in the TSH signaling pathway are frequent in autonomous nodules in Greece. This may be due to earlier exposure of the population to iodine deficiency, which was corrected in Greece only over the past two decades. Gain-of-function mutations are shared by nodules with varying histological and clinical presentations. Thus, they may represent a common molecular mechanism underlying the pathogenesis of non-autoimmune thyroid autonomy.
- Published
- 2003
41. The alpha2B adrenergic receptor deletion/insertion polymorphism in morbid obesity
- Author
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Christodoulos S. Flordellis, Apostolos G. Vagenakis, Eftihia V. Polyzogopoulou, Fotios Kalfarentzos, Kostas Spyropoulos, Athanasios G. Papavassiliou, Georgia Trakada, Gerasimos P. Sykiotis, and Neoklis A. Georgopoulos
- Subjects
Adult ,Male ,medicine.medical_specialty ,Sympathetic Nervous System ,Adrenergic receptor ,Adolescent ,Genotype ,Rest ,Receptors, Adrenergic, alpha-2 ,Internal medicine ,Diabetes mellitus ,Medicine ,Humans ,Resting energy expenditure ,Metabolic Syndrome ,Polymorphism, Genetic ,Endocrine and Autonomic Systems ,business.industry ,Middle Aged ,medicine.disease ,Obesity, Morbid ,Endocrinology ,Blood pressure ,Basal metabolic rate ,Female ,Neurology (clinical) ,Basal Metabolism ,Metabolic syndrome ,medicine.symptom ,business ,Weight gain ,Gene Deletion - Abstract
The sympathetic nervous system participates in the regulation of the basal metabolic rate (BMR) and in the manifestation of the obesity-related metabolic syndrome. A deletion/insertion germline polymorphism of the alpha(2B) adrenergic receptor that is associated with reduced agonist-promoted desensitization has been linked to low BMR in obese subjects and to a predisposition to gain weight. This study investigated an association of the alpha(2B) polymorphism with the BMR and metabolic syndrome-related parameters of morbidly obese patients. Genotype frequencies were similar in patients and in a control group. The patients' BMR, adjusted for fat-free mass, fat mass, sex and age, did not differ between alpha(2B) genotypes. The polymorphism was also not associated with the patients' BMI, systolic and diastolic blood pressure, resting heart rate, total and HDL cholesterol, triglycerides, fasting glucose and uric acid levels. These findings do not support a major functional significance of the alpha(2B) adrenergic receptor polymorphism in the present sample of morbidly obese subjects.
- Published
- 2003
42. Restoration of euglycemia and normal acute insulin response to glucose in obese subjects with type 2 diabetes following bariatric surgery
- Author
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Theodore K. Alexandrides, Eftihia V. Polyzogopoulou, Fotios Kalfarentzos, and Apostolos G. Vagenakis
- Subjects
Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,Time Factors ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Gastric Bypass ,Type 2 diabetes ,Body Mass Index ,Impaired glucose tolerance ,Insulin resistance ,Weight loss ,Reference Values ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,Diabetes Mellitus ,Humans ,Insulin ,Obesity ,Glucose tolerance test ,medicine.diagnostic_test ,business.industry ,Body Weight ,Fasting ,Glucose Tolerance Test ,medicine.disease ,Surgery ,Obesity, Morbid ,Endocrinology ,Basal (medicine) ,Diabetes Mellitus, Type 2 ,Body Composition ,Female ,medicine.symptom ,business ,Follow-Up Studies - Abstract
Insulin resistance and loss of glucose-stimulated acute insulin response (AIR) are the two major and earliest defects in the course of type 2 diabetes. We investigated whether weight loss after bariatric surgery in patients with morbid obesity and type 2 diabetes could restore euglycemia and normal AIR to an intravenous glucose tolerance test (IVGTT). We studied 25 morbidly obese patients—12 with type 2 diabetes, 5 with impaired glucose tolerance, and 8 with normal glucose tolerance (NGT)—before and after a biliopancreatic diversion (BPD) with Roux-en-Y gastric bypass (RYGBP). Twelve individuals with normal BMI served as control subjects. Twelve months after surgery, in the diabetes group, BMI decreased from 53.2 ± 2.0 to 29.2 ± 1.7 kg/m2, fasting glucose decreased from 9.5 ± 0.83 to 4.5 ± 0.13 mmol/l, and fasting insulin decreased from 168.4 ± 25.9 to 37.7 ± 4.4 pmol/l (mean ± SE; P < 0.001). AIR, the mean of insulin concentration at 2, 3, and 5 min over basal in the IVGTT, increased by 770 and 935% at 3 and 12 months after surgery, respectively (from 24.0 ± 22.7 to 209 ± 43.4 and 248 ± 33.1 pmol/l, respectively; P < 0,001). Conversely, in the NGT group, the AIR decreased by 40.5% (from 660 ± 60 to 393 ± 93 pmol/l; P = 0.027) 12 months after surgery. BPD with RYGBP performed in morbidly obese patients with type 2 diabetes leads to significant weight loss, euglycemia, and normal insulin sensitivity; but most importantly, it restores a normal β-cell AIR to glucose and a normal relationship of AIR to insulin sensitivity. This is the first study to demonstrate that the lost glucose-induced AIR in patients with type 2 diabetes of mild or moderate severity is a reversible abnormality.
- Published
- 2003
43. Increased levels and positive correlation between erythropoietin and hemoglobin concentrations in newborn children of mothers who are smokers
- Author
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Anastasia Varvarigou, Maria Makri, Nicholas G. Beratis, and Apostolos G. Vagenakis
- Subjects
medicine.medical_specialty ,Tobacco smoke ,Hemoglobins ,Pregnancy ,Internal medicine ,medicine ,Humans ,Hypoxia ,Erythropoietin ,Fetus ,business.industry ,Smoking ,Infant, Newborn ,Fetal Blood ,medicine.disease ,Confidence interval ,Arginine Vasopressin ,Fetal Diseases ,Endocrinology ,Case-Control Studies ,Cord blood ,Pediatrics, Perinatology and Child Health ,Gestation ,Female ,Hemoglobin ,business ,medicine.drug - Abstract
The mean erythropoietin concentration in the cord blood of neonates whose mothers were smokers was greater than in neonates whose mothers were not smokers. There was a significant positive correlation between erythropoietin and hemoglobin concentrations. The findings suggest that approximately one of five fetuses who are exposed to tobacco smoke are in a state of chronic hypoxia. (J P ediatr 1994;124:480-2)
- Published
- 1994
- Full Text
- View/download PDF
44. Growth and pubertal development in elite female rhythmic gymnasts
- Author
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Anastasia Theodoropoulou, Apostolos G. Vagenakis, Panagiota Paraskevopoulou, L. Varaki, Michel Leglise, Z. Kazantzi, Kostas B. Markou, and Neoklis A. Georgopoulos
- Subjects
Adult ,medicine.medical_specialty ,Aging ,Adolescent ,Gymnastics ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Growth ,Biochemistry ,Body Mass Index ,Endocrinology ,Internal medicine ,medicine ,Sexual maturity ,Humans ,Breast ,Young adult ,Child ,Exercise ,Menarche ,Bone Development ,business.industry ,Biochemistry (medical) ,Body Weight ,Puberty ,Bone age ,Genitalia, Female ,Anthropometry ,Pubic hair ,Body Height ,medicine.anatomical_structure ,El Niño ,Female ,business ,Body mass index ,Hair - Abstract
Optimal growth depends upon both environmental and genetic factors. Among environmental factors that could alter growth and sexual maturation are stress and intensive physical training. The influence of these factors has been documented in a variety of sports, but there is limited information on rhythmic gymnasts, who have entirely different training and performance requirements.The study was conducted during the 13th European Championships in Patras, Greece, and included 255 female rhythmic gymnasts, aged 11–23 yr. The study included measurement of height and weight, assessment of breast and pubic hair development, estimation of body fat and skeletal maturation, and registration of menarcheal age and parental height.Gymnasts were taller than average height for age, with mean height above and mean weight below the 50th percentile. Actual height sd score was positively correlated to weight sd score (P < 0.001), number of competitions (P = 0.01), and body mass index (BMI; P < 0.001). Predicted adult height sd score was positively correlated to weight sd score (P < 0.001) and negatively to body fat (P = 0.004).There was a delay in skeletal maturation of 1.3 yr (P < 0.001). Pubertal development was following bone age rather than chronological age. The mean age of menarche was significantly delayed from that of their mothers and sisters (P = 0.008 and P = 0.05, respectively), was positively correlated to the intensity of training and to the difference between chronological age and bone age (P < 0.001 and P = 0.002, respectively), and was negatively correlated to body fat (P < 0.001).In the elite female rhythmic gymnasts, psychological and somatic efforts have profound effects on growth and sexual development. Despite these aberrations, adult height is not expected to be affected.
- Published
- 1999
45. Insulin resistance, hyperinsulinemia, and hypertriglyceridemia in patients with coronary artery disease independent of obesity
- Author
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Venetsana Kyriazopoulou, Apostolos G. Vagenakis, Alexopoulos Dk, and Psyrogiannis Aj
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Coronary Disease ,Type 2 diabetes ,030204 cardiovascular system & hematology ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Insulin resistance ,Risk Factors ,Internal medicine ,Hyperinsulinism ,medicine ,Hyperinsulinemia ,Humans ,030212 general & internal medicine ,Obesity ,Hypertriglyceridemia ,business.industry ,Insulin ,Glucose Tolerance Test ,Middle Aged ,medicine.disease ,Endocrinology ,Case-Control Studies ,Female ,Insulin Resistance ,Cardiology and Cardiovascular Medicine ,business ,Body mass index - Abstract
Insulin resistance and hyperinsulinemia both in normal persons and those with non- insulin dependent diabetes mellitus (NIDDM) (type 2 diabetes) appears to be related to obesity. It seems also that insulin plays a role in modulating the obesity-related factors (eg, hyperinsulinemia, hyperglycemia, hypertension, hypertriglyceridemia, hypercholes terolemia, low concentrations of high-density lipoprotein cholesterol) and takes its place among the many risk factors for coronary artery disease (CAD) associated with obesity. Insulin resistance and hyperinsulinemia could play the same role in pathogenesis of CAD independently of obesity. The authors determined blood glucose and immunoreactive insulin and plasma triglyceride concentrations in the fasting state at 60 and 120 minutes after a glucose load of 75 g in 68 patients (54 men, 14 women) with angiographic evidence of CAD and in 65 healthy volunteers matched to the patients for age, gender, and body mass index (43 men and 22 women). Patients with CAD and the healthy volunteers were categorized as obese (body mass index ≥ 26 kg/m2) and nonobese (body mass index < 26 kg/m2) . Four groups of subjects were analyzed: Group A included 40 healthy (28 men and 12 women) nonobese volunteers; group B, 25 healthy (15 men and 10 women) obese volunteers; group C, 39 (30 men and 9 women) nonobese patients with CAD; and group D, 29 (24 men and 5 women) obese patients with CAD. Fasting and postchallenged 60- and 120-minute glucose values were similar in groups A and C. However, significantly higher insulin values (mU/L) were observed in group C than in group A during fasting (12.2 ±6.2 vs 91 ±3, p Significantly higher plasma triglyceride concentrations were observed in group C than in group A (149.0 ±64.1 vs 114.6 ±46.6, p < 0.01 ) and in group D compared with group B (229.4 ± 104. 7 vs 144.9 ±65.1, p < 0.001. Plasma triglyceride concentrations were similar in groups B and C. The authors conclude that patients with documented CAD are insulin resistant inde pendently of obesity.
- Published
- 1998
46. Diurnal Variation of Plasma Cortisol Levels in Infancy
- Author
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Stephanos Mantagos, Apostolos G. Vagenakis, and A Moustogiannis
- Subjects
medicine.medical_specialty ,Hydrocortisone ,business.industry ,Endocrinology, Diabetes and Metabolism ,Diurnal temperature variation ,Infant, Newborn ,Infant ,Sensitivity and Specificity ,Circadian Rhythm ,Endocrinology ,Plasma cortisol ,Internal medicine ,Pediatrics, Perinatology and Child Health ,Normal children ,medicine ,Humans ,Circadian rhythm ,business - Abstract
Normal children and adults show diurnal variation of plasma cortisol levels reaching peak values around 08.00 h and lower values around 24.00 h. Despite numerous studies on diurnal variation of plasma cortisol levels in children, the age of appearance of a circadian rhythm has not been definitely established. The purpose of this study was to investigate the development of cortisol circadian rhythm in infancy. In seventy healthy, full-term infants, less than six months old, plasma cortisol was measured at 10.30 h and 22.30 h. The mean +/- SEM values of daytime plasma cortisol at one to four weeks of life were 159 +/- 41, 116 +/- 43, 240 +/- 54 and 456 +/- 95 nmol/l and the night-time values were 129 +/- 40, 99 +/- 44, 131 +/- 78 and 430 +/- 105 nmol/l, respectively. No statistically significant differences were found between daytime and night-time cortisol values during the first four weeks of life. In contrast, the daytime values of plasma cortisol were 295 +/- 62 at the age of 2-3 months, 211 +/- 43 at 4-5 months and 291 +/- 31 nmol/l at 6 months of life, and night-time values were 166 +/- 52, 119 +/- 35 and 109 +/- 21 nmol/l, respectively, which were statistically significant (p < 0.05). These data clearly indicate that cortisol circadian rhythm starts between the second and third month of life.
- Published
- 1998
- Full Text
- View/download PDF
47. The Effect of Light on Plasma Melatonin Levels in Premature Infants
- Author
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Apostolos G. Vagenakis, Anastasia Moustogiannis, Stephanos Mantagos, and Maria Makri
- Subjects
medicine.medical_specialty ,Light ,Endocrinology, Diabetes and Metabolism ,Gestational Age ,Pineal Gland ,Group B ,Melatonin ,Pineal gland ,Endocrinology ,Internal medicine ,medicine ,Birth Weight ,Humans ,Full Term ,Developmental maturation ,business.industry ,Infant, Newborn ,Gestational age ,Light deprivation ,medicine.anatomical_structure ,Pediatrics, Perinatology and Child Health ,Gestation ,business ,Infant, Premature ,medicine.drug - Abstract
Recent studies have shown that full term neonates actively secrete melatonin and that light deprivation during the first 72 h of life significantly increases plasma melatonin levels. In order to evaluate pineal gland activity and responsiveness to light in premature infants, we measured plasma melatonin levels in 23 healthy infants, 33-36 weeks of gestation, during their first week of life. Nine infants (Group A) remained under constant illumination conditions for 48 hour prior to melatonin measurements. Fourteen infants (Group B) were exposed for the same time period to an artificial alternation of day and night cycles by covering the eyes of the infants with eye pads during the night (20.00-08.00 h). Mean +/- SEM plasma melatonin at 20.00 h, 04.00 h, 12.00 h and 20.00 h was 14.8 +/- 1.6, 16.2 +/- 2.8, 18.7 +/- 3.1, 20.9 +/- 3.1 pg/ml in Group A and 20.5 +/- 3.2, 22.3 +/- 2.9, 20.2 +/- 2.2, 18.5 +/- 2.2 pg/ml in Group B respectively. The differences observed between the two groups were not statistically significant. Our results indicate that at this gestational age the pineal gland is actively secreting melatonin but does not respond to the light alternations attempted. Further studies are needed in order to evaluate the developmental maturation of the pineal gland in humans.
- Published
- 1996
- Full Text
- View/download PDF
48. Prolactin, growth hormone and insulin-like growth factor-I in newborn children of smoking mothers
- Author
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Apostolos G. Vagenakis, Nicholas G. Beratis, Maria Makri, and Anasiasia Varvarigou
- Subjects
endocrine system ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Radioimmunoassay ,Tobacco smoke ,Insulin-like growth factor ,Endocrinology ,Pituitary Hormones, Anterior ,Pregnancy ,Internal medicine ,medicine ,Endocrine system ,Humans ,Insulin-Like Growth Factor I ,Fetus ,business.industry ,Smoking ,Infant, Newborn ,Gestational age ,Fetal Blood ,Prolactin ,Cord blood ,Growth Hormone ,Prenatal Exposure Delayed Effects ,Female ,Immunoradiometric Assay ,business ,hormones, hormone substitutes, and hormone antagonists ,Infant, Premature ,Hormone - Abstract
Since maternal smoking causes fetal circulatory abnormalities, as well as disturbances of the maternal endocrine equilibrium, we measured the PRL, hGH and insulin-like growth factor-I (IGF-I) concentrations in the cord and venous blood of neonates of smoking mothers to determine whether or not the tobacco smoke affects the endocrine status of the neonate.The above hormones were measured in the cord blood of the newborns of both smoking and non-smoking mothers. Also, PRL and hGH were determined at 24 and 72 hours after birth in newborns of both groups.Fifty-three newborns of smoking and 47 newborns of non-smoking mothers were investigated. Seventeen of the newborns of the smoking and 21 of the non-smoking mothers were preterm. The remainder were full-term.PRL was measured with a solid-phase immunoradiometric assay, hGH with a solid-phase two-site immunoradiometric assay and IGF-I with a solid-phase radioimmunoassay after extraction with acid-ethanol.The median value of PRL in the 17 preterm newborns of smoking mothers was 4941 mU/I (range 1322-7230), whereas in the 21 preterm newborns of non-smoking mothers it was 2013 mU/I (range 243-4740) (P = 0.0002). The median hGH value in the above subjects was 102.0 mU/I (range 35.2-208.4) and 59.8 mU/I (range 11.6-134.2), respectively (P = 0.0039). The median IGF-I was 580.7 U/I (range 253.2-4851.1) and 530.6 U/I (range 239.6-3591.5), respectively (P = 0.429). In the 36 full-term newborns of smoking mothers the median PRL value was 5171 mU/I (range 2074-7530), whereas in the 26 full-term newborns of non-smoking mothers it was 5081 (range 244-6540) (P = 0.048). The median hGH was 69.6 mU/I (range 42.3-280.0) and 32.2 mU/I (range 6.2-200.0), respectively (P = 0.0031). Also, the median IGF-I value was 926.3 U/I (range 348.5-5344.7) and 462.1 U/I (range 250.2-1578.7), respectively (P = 0.0024). On the 3rd day the PRL in the preterm neonates of both smoking and non-smoking mothers showed the same 16.5% drop, and thus the difference between the groups was maintained. A similar reduction in the hormone levels was observed in the full term neonates.The findings indicate that the maternal tobacco-smoking causes disturbances of the endocrine status of the fetus, as shown by the increased levels of PRL, hGH and IGF-I, which are more pronounced between 30 and 37 weeks of gestation than at term.
- Published
- 1994
49. Growth hormone, insulin-like growth factor-I and prolactin in small for gestational age neonates
- Author
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Anastasia Varvarigou, Nicholas G. Beratis, Maria Makri, and Apostolos G. Vagenakis
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,Cord ,medicine.medical_treatment ,Biology ,Insulin-like growth factor ,Reference Values ,Internal medicine ,medicine ,Humans ,Insulin-Like Growth Factor I ,Growth factor ,Osmolar Concentration ,Infant, Newborn ,Gestational age ,Venous blood ,medicine.disease ,Fetal Blood ,Somatomedin ,female genital diseases and pregnancy complications ,Prolactin ,Endocrinology ,Growth Hormone ,Pediatrics, Perinatology and Child Health ,Infant, Small for Gestational Age ,Small for gestational age ,Female ,hormones, hormone substitutes, and hormone antagonists ,Developmental Biology - Abstract
Growth hormone (hGH), insulin-like growth factor-I (IGF-I) and prolactin (PRL) were measured in the cord and venous blood of small for gestational age (SGA) neonates in order to evaluate their endocrine status during the first 3 days of life. Although there were SGA newborns with both high and normal levels of hGH, the mean ( ± SD) concentration of hGH in the cord blood of the SGA neonates was 72.1 ± 50.6 ng/ml, whereas in the appropriate for gestational age (AGA) newborns it was 37.0 ± 23.5 (p = 0.001). The IGF-I in the cord blood of the SGA and the AGA newborns was 194.2 ± 174.8 ng/ml and 77.3 ± 50.2, respectively (p = 0.013). The PRL in the SGA and AGA newborns was 184.8 ± 62.4 ng/ml and ± 60.5, respectively (p = 0.0005). On the 3rd day the hGH in the SGA babies was 50.7 ± 41.2, whereas in the AGA it was 24.3 ± 12.3 (p = 0.034). On the same day the IGF-I was ± 120.9 and 44.8 ± 31.6, respectively (p > 0.05). Similarly, the PRL was 157.1 ± 52.3 and 90.9 ± 52.5, respectively (p = 0.0008). All neonates with high hGH concentrations had low IGF-I levels, whereas of those with normal hGH half had high and half normal IGF-I levels. There was no difference in the hormone levels between symmetric and asymmetric intrauterine growth-retarded infants. The findings suggest that the SGA neonates are heterogeneous comprising three groups. The neonates with high hGH and low IGF-I may have resistance at the level of the hGH receptor or a defect in IGF-I synthesis, whereas those with normal hGH and high IGF-I may have a post-IGF-I receptor defect, with compensatory increase in IGF-I synthesis independent of hGH control.
- Published
- 1994
50. Abnormal overnight dexamethasone suppression test in subjects receiving rifampicin therapy
- Author
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Venetsana Kyriazopoulou and Apostolos G. Vagenakis
- Subjects
Adult ,Male ,medicine.medical_specialty ,Hydrocortisone ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Antibiotics ,Biochemistry ,Dexamethasone ,Cushing syndrome ,Endocrinology ,Internal medicine ,medicine ,Humans ,False Positive Reactions ,Diagnostic Errors ,Cushing Syndrome ,business.industry ,Biochemistry (medical) ,Metabolism ,Middle Aged ,medicine.disease ,Dexamethasone suppression test ,Toxicity ,Prednisolone ,Rifampin ,business ,Rifampicin ,medicine.drug - Abstract
We have studied the effects of rifampicin on the overnight 1-mg dexamethasone suppression test usually employed to exclude suspected Cushing's syndrome. Previous observations indicate that in humans, rifampicin profoundly attenuates the biological effects of hydrocortisol and prednisolone, probably by increasing the metabolism of these drugs in the liver. The study was carried out in 16 normal volunteers. All subjects had a normal overnight 1-mg dexamethasone suppression test (468 +/- 86 vs. 32 +/- 21 nmol/L; mean +/- SD). In 8 subjects treated with rifampicin (600 mg) for 10 days, the inhibitory effect of dexamethasone on serum cortisol was completely prevented (575 +/- 114 vs. 434 +/- 82). In the remaining 8 rifampicin-treated subjects, the inhibitory effect of 1, 2, or 3 mg dexamethasone on serum cortisol was not observed. When 4 mg dexamethasone were administered, the serum cortisol level was 193 nmol/L, above the expected normal suppression value. The plasma dexamethasone concentration was very low after rifampicin treatment (range, 1.2-4.8 nmol/L). We conclude that when patients are treated with rifampicin, the standard overnight dexamethasone suppression test not only has no diagnostic value, but can be very misleading.
- Published
- 1992
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