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Ioannis Ilias

Publications and source records attributed to Ioannis Ilias.

At least 19 recordsLinked to original sources
PubMed2006

Differentiated thyroid cancer: comparison of therapeutic iodine 131 biological elimination after discontinuation of levothyroxine versus administration of recombinant human thyrotropin.

The biological elimination of therapeutic 131I in patients with differentiated thyroid cancer (DTC), post total or near-total thyroidectomy, was compared after withholding levothyroxine suppression against administration of recombinant human thyrotropin without stopping levothyroxine. In 163 patients (group G1) levothyroxine was withheld before 131I therapy: in 138 patients the tumor was limited to the thyroid bed (group G1.1) and in 25 patients metastases were present (group G1.2). A second group of patients (G2; n = 28) received 131I therapy after administration of recombinant human thyrotropin without stopping levothyroxine. Mean retained 131I activity (as a percentage of the administered dose) was 5%-29% (group G1.1), 20%-43% (group G1.2) and 1%-17% (group G2). The effective half-life of 131I was 0.59-0.69 days (group G1.1), 0.87-1.22 days (group G1.2) and 0.38-0.44 days (group G2). In conclusion, the use of recombinant human thyrotropin to prepare patients with thyroid cancer for therapy with 131I shortens its effective half-life and reduces its retained activity compared to preparation with discontinuation of levothyroxine suppression.

Adolescent↗
PubMed2006

Discordant localization of 2-[18F]-fluoro-2-deoxy-D-glucose in 6-[18F]-fluorodopamine- and [(123)I]-metaiodobenzylguanidine-negative metastatic pheochromocytoma sites.

BACKGROUND: Although the majority of pheochromocytomas (PHEO) are benign, a subset is malignant. Computed tomography (CT) and magnetic resonance imaging (MRI) localize PHEO with high sensitivity but, because of limited specificity, [(131)I]- or [(123)I]-metaiodobenzylguanidine ([(131)I]- or [(123)I]-MIBG) is often used as a complementary agent. 6-[18F]-fluorodopamine ([18F]-DA) has been developed as a radiopharmaceutical for the targeting of noradrenergic pathways, and has been shown to result in a better detection rate of PHEO sites than MIBG; however, [18F]-DA has shown a lack of accumulation in some patients with metastatic PHEO. METHODS: Five patients with widespread metastatic PHEO who had CT and MRI evidence of metastatic disease (one man and four women; age range, 25-64 years), and who underwent imaging with [(123)I]-MIBG, [18F]-DA and 2-[18F]-fluoro-2-deoxy-D-glucose ([18F]-FDG), were evaluated retrospectively. Tomographic imaging was performed and positron emission tomography (PET) images were inspected visually and quantitatively. RESULTS: All five patients had [(123)I]-MIBG scans that grossly underestimated the extent of disease when compared with conventional CT and MRI. All lesions seen on [(123)I]-MIBG scans were detected on [18F]-DA scans, which also detected additional lesions. Nonetheless, [18F]-DA also failed to detect numerous lesions seen on CT and MRI. In all of these cases, [18F]-FDG PET showed lesions that were not detected on either [(123)I]-MIBG or [18F]-DA scans. CONCLUSIONS: When [(123)I]-MIBG or [18F]-DA fails to localize lesions seen on conventional imaging studies, [18F]-FDG may be recommended as an ancillary test for the diagnosis and localization of metastatic PHEO. This is particularly important in patients with aggressive PHEO.

3-Iodobenzylguanidine↗
PubMed2006

Current trends in functional imaging of pheochromocytomas and paragangliomas.

Most pheochromocytomas/paragangliomas should be evaluated with anatomical imaging (computed tomography or magnetic resonance imaging) followed by functional imaging (nuclear medicine modalities). Functional imaging assures that the tumor is indeed a pheochromocytoma/paraganglioma and enables more thorough localization, especially detecting as many lesions as possible (in particular for metastatic disease). Functional imaging for pheochromocytomas/paragangliomas, can use radiolabeled ligands specific for pathways of synthesis, metabolism, and inactivation of catecholamines or nonspecific ligands. In an overview of the available nuclear medicine modalities, we summarize the accumulated experience and recommend when functional imaging should be applied to patients with pheochromocytoma/paraganglioma.

Adrenal Gland Neoplasms↗
PubMed2006

Interleukin-6: a cytokine and/or a major modulator of the response to somatic stress.

The hypothalamic-pituitary-adrenal (HPA) axis and the proinflammatory cytokines (and interleukin-6 [IL-6] in particular) are enmeshed in the response to somatic stress, either in health or in acute or chronic disease. Usually IL-6 is elevated in states of septic (such as sepsis) or aseptic inflammation (such as rheumatoid arthritis). Exercise is a form of somatic stress. Local tissue IL-6 elevation is noted during shorter and less intense exercise, whereas brief peripheral IL-6 "bursts" are observed with longer and more intense exercise. Therapeutic interventions that target IL-6 or its soluble receptor are currently assessed, with an emphasis on autoimmune diseases and inflammatory conditions.

Humans↗
PubMed2006

Pheochromocytoma: physiopathologic implications and diagnostic evaluation.

Pheochromocytoma (PHEO) is a chromaffin cell tumor embryologically arising from the neural crest tissue. The dominant secretory products of PHEO are catecholamines: noradrenaline (norepinephrine), adrenaline (epinephrine), and to a lesser extent dopamine. In addition to catecholamines, PHEO cells also elaborate and release several neuropeptides and inflammatory cytokines which can exert intra-adrenal and extra-adrenal systemic effects and cause characteristic clinical syndromes. In a concise review we present the intra-adrenal and extra-adrenal pathophysiologic implications of PHEO and the nuclear medicine modalities that permit functional imaging of physiological processes and help localize these tumors. The specific pathways of synthesis, metabolism, and inactivation of catecholamines (of PHEOs and paragangliomas) can be used as means to develop suitable tracers for positron emission tomography (PET) ligands. In this review we focus on imaging with PET using [(18)F]-fluorodopamine, [(18)F]-fluorohydroxyphenylalanine, [(11)C]-epinephrine, or [(11)C]-hydroxyephedrine and examine how functional imaging can often complement traditional anatomical imaging modalities and other scintigraphic techniques.

Animals↗
PubMed2006

Lack of association between alpha2B-adrenergic receptor polymorphism and risk of restenosis following coronary angioplasty and stent implantation--preliminary report.

BACKGROUND: A genetic association/prospective follow-up study was conducted to investigate whether genetic variation of the alpha(2B)-adrenergic receptor gene was associated with the risk of restenosis in 96 Greek coronary artery disease patients undergoing coronary angioplasty and stent implantation. METHODS: For comparison of genotype frequency, a control group of 83 asymptomatic individuals was also studied. The end-point of the current study was the incidence of restenosis at 7 months of clinical follow-up. RESULTS: The majority of patients (70/96) had the insertion/insertion genotype, fewer patients (23/96) had the insertion/deletion genotype and only 3/96 had the deletion/deletion genotype; overall the frequency distribution was not different from that of the control subjects. Restenosis occurred in 15 of the 96 patients. CONCLUSIONS: In the population studied, alpha(2B)-adrenoreceptor polymorphisms were not found to predispose patients to an increased incidence of restenosis. Nevertheless, these findings should be considered as preliminary, taking into account the small number of patients that were studied and the rarity of the deletion/deletion genotype.

Adult↗
PubMed2006

Anxiety and depression in Greek nursing and medical personnel.

The relatively low number of nurses compared to physicians in Greece and the few available studies on the psychological problems of the health professionals led to comparison of anxiety and depression for 76 Greek nursing personnel (20 men, M age: 32.8 yr., SD: 3.8 yr., and 56 women, M age: 36.6 yr., SD: 7.7 yr.) and 66 doctors (35 men, M age: 35.9 yr., SD: 8.9 yr. and 31 women, M age: 32.7 yr., SD: 8.1 yr.) using validated translations of the Spielberger State-Trait Anxiety Inventory and the Beck Depression Inventory. Male nurses had the lowest scores on trait anxiety, while female doctors had the highest scores, followed by female nurses. Depression scores were not different between doctors and nurses, regardless of sex. Age and depression scores were positively correlated (Spearman rho = .31) only for the female nurses. The findings suggest that interventions for diagnosis and stress management in the health-care workplace should be equally targeted for nursing and medical personnel.

Adult↗
PubMed2005

Cushing's syndrome due to ectopic corticotropin secretion: twenty years' experience at the National Institutes of Health.

CONTEXT: Ectopic ACTH secretion (EAS) is difficult to diagnose and treat. We present our experience with EAS from 1983 to 2004. SETTING: The study was performed at a tertiary care clinical research center. PATIENTS: Ninety patients, aged 8-72 yr, including 48 females were included in the study. INTERVENTIONS AND OUTCOME MEASURES: Tests included 8 mg dexamethasone suppression, CRH stimulation, inferior petrosal sinus sampling (IPSS), computed tomography, octreotide scan, magnetic resonance imaging, and/or venous sampling. Therapies, pathological examinations, and survival were noted. RESULTS: Eighty-six to 94% of patients did not respond to CRH or dexamethasone suppression, whereas 66 of 67 had negative IPSS. To control hypercortisolism, 62 patients received medical treatment, and 33 had bilateral adrenalectomy. Imaging localized tumors in 67 of 90 patients. Surgery confirmed an ACTH-secreting tumor in 59 of 66 patients and cured 65%. Nonthymic carcinoids took longest to localize. Deaths included three of 35 with pulmonary carcinoid, two of five with thymic carcinoid, four of six with gastrinoma, two of 13 with neuroendocrine tumor, two of two with medullary thyroid cancer, one of five with pheochromocytoma, three of three with small-cell lung cancer, and two of 17 with occult tumor. Patients with other carcinoids and ethesioneuroblastoma are alive. CONCLUSIONS: IPSS best identifies EAS. Initial failed localization is common and suggests pulmonary carcinoid. Although only 47% achieved cure, survival is good except in patients with small-cell lung cancer, medullary thyroid cancer, and gastrinoma.

Adolescent↗
PubMed2005

Major depression is associated with significant diurnal elevations in plasma interleukin-6 levels, a shift of its circadian rhythm, and loss of physiological complexity in its secretion: clinical implications.

BACKGROUND: Major depressive disorder (MDD) is associated with increased risk for premature coronary heart disease and bone loss. Single time measurements of plasma IL-6, a good predictor of future risk for both cardiovascular disease and osteoporosis, revealed significant elevations in depressed patients. The objective of this study was to rigorously compare plasma IL-6 levels, measured over 24 h, in MDD patients and healthy controls. Given the activating role of IL-6 on the hypothalamic-pituitary-adrenal (HPA) axis, and the relevance of its dysregulation in MDD, we also analyzed the relations between IL-6 and cortisol levels. METHODS: We studied nine patients and nine controls, individually matched by gender, age (+/-5 yr), body mass index (+/-2 kg/m2), and menstrual cycle phase. Diagnosis of MDD was confirmed by structured clinical interview based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I diagnostic criteria. Self-reported mood ratings were assessed by multiple visual analog scales. The rhythmicity and complexity of IL-6 and cortisol secretion were tested by cosinor analyses, approximate entropy (ApEn) and cross-ApEn algorithms. RESULTS: MDD patients had significant mean IL-6 elevations from 1000-1200 h and at 1500 h (P ranging from <0.05 to <0.01) vs. controls. In addition, in MDD, the circadian rhythm of IL-6 was shifted by 12 h, and its physiological complexity was reduced, with no difference in the cross-ApEn of IL-6 and cortisol between the two groups, and significant time-lagged correlations only in the controls. IL-6 levels correlated significantly with mood ratings. CONCLUSIONS: We report profound morning elevations of plasma IL-6 and a reversal of its circadian rhythm in MDD patients, in the absence of hypercortisolism. These findings may be relevant to the increased risk for coronary heart disease and bone loss in MDD.

Adult↗
PubMed2005

Evaluation and treatment of Cushing's syndrome.

Cushing's syndrome results from sustained pathologic hypercortisolism caused by excessive corticotropin (ACTH) secretion by tumors in the pituitary gland (Cushing's disease, 70%) or elsewhere (15%), or by ACTH-independent cortisol secretion from adrenal tumors (15%). The clinical features are variable, and no single pattern is seen in all patients. Those features most specific for Cushing's syndrome include abnormal fat distribution, particularly in the supraclavicular and temporal fossae, proximal muscle weakness, wide purple striae, and decreased linear growth with continued weight gain in a child. Patients with characteristics of glucocorticoid excess should be screened with measurements of saliva or urine cortisol or dexamethasone suppression testing. The diagnosis of Cushing's syndrome should be followed by the measurement of plasma ACTH concentration to determine whether the hypercortisolism is ACTH-independent. In ACTH-dependent patients, bilateral inferior petrosal sinus sampling with measurement of ACTH before and after administration of ACTH-releasing hormone most accurately distinguishes pituitary from ectopic ACTH secretion. Surgical resection of tumor is the optimal treatment for all forms of Cushing's syndrome; bilateral adrenalectomy, medical treatment, or radiotherapy are sought in inoperable or recurrent cases. The medical treatment of choice is ketoconazole. The prognosis is better for Cushing's disease and benign adrenal causes of Cushing's syndrome than adrenocortical cancer and malignant ACTH-producing tumors.

Adrenalectomy↗
PubMed2005

New functional imaging modalities for chromaffin tumors, neuroblastomas and ganglioneuromas.

Nuclear medicine modalities use radiolabeled ligands that either follow metabolic pathways or act on cellular receptors. Thus, they permit functional imaging of physiological processes and help to localize sites such as tumors that harbor pathological events. The application of positron emission tomography (PET) ligands to the specific pathways of synthesis, metabolism and inactivation of catecholamines found in chromaffin tumors, neuroblastomas and ganglioneuromas can be used to provide a more thorough localization of these types of tumor. Recent advances have been made in functional imaging to localize pheochromocytomas, paragangliomas, neuroblastomas and ganglioneuromas, including approaches based on PET with [(18)F]fluorodopamine, [(18)F]fluorohydroxyphenylalanine, [(11)C]epinephrine or [(11)C]hydroxyephedrine. Such functional imaging can complement computed tomography or magnetic resonance imaging and other scintigraphic techniques to localize these tumors before surgical or medical therapeutic approaches are considered.

Adrenal Gland Neoplasms↗
PubMed2005

New therapeutic options for the metabolic syndrome: what's next?

The metabolic syndrome (MSX), characterized by obesity, insulin resistance, dyslipidemia and hypertension, increases the risk of cardiovascular morbidity and mortality. It has recently been hypothesized that MSX and type 2 diabetes are caused by triglyceride and long-chain fatty acid accumulation in liver, muscle, pancreatic islets and selected brain areas. This lipocentric approach is integrated with analysis of inflammation associated with end-organ damage, including the vascular wall. Genes and proteins contributing to insulin resistance, beta cell dysfunction and vascular wall damage have been identified. Transcription factors and coactivators, including peroxisome proliferator-activated receptor gamma (PPARgamma) coactivator-1 are crucial in mediating insulin resistance and accelerating vascular wall inflammation, and represent promising therapeutic targets. New pharmacological strategies include dual PPARalpha/gamma agonists, drugs with pleiotropic effects or combination therapies.

Cardiovascular Diseases↗
PubMed2005

Glucocorticoid-induced osteoporosis: from basic mechanisms to clinical aspects.

Glucocorticoid (GC)-induced osteoporosis (GCOP) is the most common cause of osteoporosis in adults aged 20-45 years as well as the most common cause of iatrogenic osteoporosis. GC excess, either endogenous or exogenous, induces bone loss in 30-50% of cases. Indeed, bone loss leading to fractures is perhaps the most incapacitating, sometimes partially irreversible, complication of GC therapy. Nevertheless, GCOP is often underdiagnosed and left untreated. The following article provides an update on the cellular and molecular mechanisms implicated in the pathophysiology of GC-induced bone loss, as well as some guidelines on diagnostic, preventive and therapeutic strategies for this medical condition, in an effort to promote a better knowledge and greater awareness of GCOP by both the patient and the physician.

Animals↗
PubMed2005

Preliminary report: psychological assessment of Greek women with diabetes during pregnancy.

23 Greek pregnant women with type 1 diabetes had a higher mean score on the Maudsley Obsessive-Compulsive Inventory in the second and third trimesters of pregnancy than 13 women with gestational diabetes. Long-term changes in the lifestyle of the former may apparently lead to this higher mean. For those with gestational diabetes, higher scores of alexithymia were correlated with slightly worse glycemic control.

Adult↗
PubMed2005

Neuropsychological correlates of Greek alcoholic patients who report memory disturbances.

We studied 40 male and 37 female (M age=63 yr.) Greek alcoholic patients and an equal number of control subjects. Both groups were evaluated with the Mini-Mental State Examination, the Syndrome Short Test, the Verbal Fluency Test (Category & Letter), the Clock Test, and the Digit Span (Forward and Backward from the Wechsler Adult Intelligence Scale-Revised). Alcoholic patients had statistically significant lower scores on MMSE, Verbal Fluency Test, and Digit Span, and higher scores on the Syndrome Short Test, while positive correlations were found among MMSE, Verbal Fluency Test, Clock Test, Digit Span-Backward, and age. These findings point to frontal lobe dysfunction in Greek alcoholic patients which is not different from that shown in patients from diverse ethnic and cultural backgrounds.

Adult↗
PubMed2004

L-Carnitine and acetyl-L-carnitine in the treatment of complications associated with HIV infection and antiretroviral therapy.

L-Carnitine (LC) and acetyl-L-carnitine (ALC) play major roles in cell energy and lipid metabolism. Supplementation with these nutrients, which are highly popular in USA, has been associated with favorable effects, including anti-oxidant action, neuro- and cardioprotection, immunomodulation, and cognitive enhancement. Patients with HIV infection and undergoing highly active antiretroviral therapy (HAART) often develop complications, such as polyneuropathy, skeletal myopathy, dyslipidemia and lipodystrophy, which have been linked to mitochondrial dysfunction. Moreover, these patients are often LC-deficient. Thus, they may benefit from LC and ALC supplementation. Indeed, oral, i.v., or i.m. administration of large doses of LC and/or ALC to HIV positive subjects untreated/treated with HAART was shown to: (1) increase the number of CD4 cells and reduce lymphocyte apoptosis; (2) improve symptoms of polyneuropathy; (3) prevent cardiovascular damage from wasting and diarrhea syndromes; (4) decrease serum levels of triglycerides and TNFalpha. No significant toxicities were associated with LC and ALC treatment. Although promising, most of these findings derive from small uncontrolled clinical trials. Further research is warranted to prove the efficacy and safety of LC and ALC supplementation in patients with complications of HIV infection and HAART.

Journal Article↗
PubMed2004

Hypothalamic-pituitary-adrenal axis dysfunction in critically ill patients with traumatic brain injury: incidence, pathophysiology, and relationship to vasopressor dependence and peripheral interleukin-6 levels.

OBJECTIVE: To investigate hypothalamic-pituitary-adrenal axis function in patients requiring mechanical ventilation for traumatic brain injury and to assess the relation of hypothalamic-pituitary-adrenal axis abnormalities with vasopressor dependence and peripheral cytokine levels. DESIGN: Prospective study. SETTING: General intensive care unit in a university teaching hospital. PATIENTS: Forty patients (33 men and 7 women) with moderate to severe traumatic brain injury (mean age, 37 +/- 16 yrs) were studied the day after termination of mechanical ventilation (7-60 days after trauma). INTERVENTIONS: First, a morning blood sample was obtained to measure baseline cortisol, corticotropin, interleukin-6, and tumor necrosis factor alpha. Subsequently, 1 microg of synthetic corticotropin was injected intravenously, and 30 mins later, a second blood sample was drawn to determine stimulated plasma cortisol. Based on data derived from healthy volunteers, patients having stimulated cortisol levels <18 microg/dL were defined as nonresponders to the low-dose stimulation test. Thirty-one patients underwent also a human corticotropin releasing hormone test. MEASUREMENTS AND MAIN RESULTS: In traumatic brain injury patients, mean baseline and low-dose stimulation test-stimulated cortisol levels were 17.2 +/- 5.4 microg/dL and 24.0 +/- 6.6 microg/dL, respectively. The median increment in cortisol was 5.9 microg/dL. Basal corticotropin levels ranged from 3.9 to 118.5 pg/mL. Six of the 40 patients (15%) failed the low-dose stimulation test. The human corticotropin releasing hormone test (performed in 26 responders and five nonresponders) revealed diminished cortisol release only in the low-dose stimulation test nonresponder patients. Corticotropin responses to corticotropin releasing hormone were consistent with both primary (three patients) and/or secondary (two patients) adrenal dysfunction. In retrospect, nonresponders to the low-dose stimulation test more frequently required vasopressors (6/6 [100%] vs. 16/34 [47%]; p =.02) and for a longer time interval (median, 0 vs. 293 hrs; p =.006) compared with responders. Furthermore, nonresponders had higher interleukin-6 levels compared with responders (56.03 vs. 28.04 pg/mL; p =.01), whereas tumor necrosis factor alpha concentrations were similar in the two groups (2.42 vs. 1.55 pg/mL; p =.53). CONCLUSIONS: Adrenal cortisol secretion after dynamic stimulation is deficient in a subset of critically ill patients with moderate to severe head injury. This disorder is associated with prior vasopressor dependency and higher interleukin-6 levels.

Adrenocorticotropic Hormone↗