Ioannis Stefanidis

University of Thessaly, Iolcus, Thessaly, Greece

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Publications (193)428.92 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Both exercise training and treatment with dopamine agonists (DA) have been used with success for the amelioration of uremic Restless Legs Syndrome (RLS) symptoms. However, no data are available combining those two approaches. The aim of the current randomized double blind placebo controlled study was to investigate the effects of a 6-month intradialytic exercise training in combination with a low dose of dopamine agonists in patients suffering from uremic RLS symptoms. Fourteen stable hemodialysis patients with RLS were randomly assigned into the exercise training plus DA group and the exercise training plus placebo group. Both combinations were found to equally reduce uremic RLS symptoms by approximately 60%. The combination of low dose of DA with aerobic exercise training could be considered an alternative approach to high DA dosage regimes in reducing RLS symptoms' severity.
    ASAIO journal (American Society for Artificial Internal Organs: 1992) 08/2015; DOI:10.1097/MAT.0000000000000271 · 1.52 Impact Factor
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    ABSTRACT: It is known that inadequate erythropoietin (EPO) production contributes to the pathogenesis of anemia of inflammation, although the exact molecular mechanism is unknown. Aryl hydrocarbon receptor (AhR) may compete with hypoxia inducible factor-2α (HIF-2α), the master regulator of EPO production, for binding with HIF-1β. The effect of kynurenine, an endogenous AhR activator increasing in inflammation, on EPO and hepcidin production was evaluated. HepG2 cells were treated with the hypoxia mimetic CoCl2, kynurenine, the AhR inhibitor CH223191 and combinations between them. EPO and hepcidin production were measured with ELISA. HIF-2α and CYP1A1 levels, a transcriptional target of AhR, were assessed by western blotting. CoCl2 increased EPO production and decreased hepcidin and CYP1A1. Kynurenine exerts the opposite effects. Wherever CH223191 added, the inhibitor overcorrected kynurenine-induced alterations both in the presence or absence of CoCl2. Also treatment with CH223191 alone increased EPO and decreased hepcidin indicating that there is a degree of constitutive AhR activation possibly by other endogenous AhR activators. In conclusion, kynurenine by competing HIF-2α may contribute to anemia of inflammation by decreasing EPO and increasing hepcidin production. The fact that inactivation of AhR alone induces EPO makes this transcription factor a potential therapeutic target in situations that require increased EPO. Copyright © 2015 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.
    Experimental hematology 08/2015; DOI:10.1016/j.exphem.2015.08.010 · 2.48 Impact Factor
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    ABSTRACT: Indoleamine 2,3-dioxygenase (IDO) is expressed in antigen presenting cells and exerts immunosuppressive effects on CD4+ T-cells. One mechanism is through the inhibition of aerobic glycolysis. Another prerequisite for T-cell proliferation and differentiation into effector cells is the increased fatty acid (FA) synthesis. The effect of IDO on enzymes involved in FA synthesis was evaluated in primary human cells both in MLRs in the presence or not of the IDO inhibitor 1-DL-methyl-tryptophan (1-MT), and in stimulated CD4+ T-cells in the presence or not of the general control nonderepressible 2 (GCN2) kinase activator tryptophanol (TRP). IDO or TRP inhibited cell proliferation. By assessing the level of GCN2 kinase or mammalian target of rapamycin complex 1 (mTORC1) substrates along with a kynurenine free system we showed that IDO exerts its effect mainly through activation of GCN2 kinase. IDO or TRP downregulated ATP-citrate lyase (ACL) and acetyl coenzyme A carboxylase 1 (ACC1), key enzymes involved in FA synthesis. Also, IDO or TRP altered the expression of enzymes that control carbon atoms availability for FA synthesis, such as lactate dehydrogenase-A (LDH-A), pyruvate dehydrogenase (PDH), glutaminase 1 (GLS1) and glutaminase 2 (GLS2), in a way that inhibits FA synthesis. In conclusion, IDO through GCN2 kinase activation inhibits CD4+ T-cell proliferation and downregulates key enzymes that directly or indirectly promote FA synthesis, a prerequisite for CD4+ T-cell proliferation and differentiation into effector cell lineages. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Immunology 07/2015; 146(2). DOI:10.1111/imm.12502 · 3.80 Impact Factor
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    ABSTRACT: Background: Urate through NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome-dependent caspase-1 activation stimulates macrophages to secrete inteleukin-1β (IL-1β). Urate also enhances adaptive immunity indirectly through its effect on antigen presenting cells. In this study, the direct effect of urate on isolated primary human T-cells was evaluated. Methods: Isolated T-cells were cultured with or without monosodium urate crystals in the presence or not of the NLRP3 inflammasome inhibitor glyburide. Activated cleaved caspase-1 was assessed by means of western blotting, whereas caspase-1 activity was measured colorimetrically in the cell lysates. IL-1β was measured in the supernatants by means of enzyme-linked immunosorbent assay. T-cell proliferation was assessed by means of bromodeoxyuridine labelling and immunoenzymatic detection. Results: Urate induced caspase-1 activation and IL-1β release by T-cells. It also induced proliferation of T-cells. Glyburide inhibited urate-induced caspase-1 activation, IL-1β secretion and proliferation. Conclusions: Urate, a well defined danger signal, stimulates directly human T-cells in a NLRP3 infmmasomela-dependent way. The subsequent IL-1β secretion could enhance inflammation, whereas expansion of T-cell clones could facilitate a subsequent adaptive immune response. © 2015, Lithografia Antoniadis I - Psarras Th G.P. All rights reserved.
    Hippokratia 06/2015; 19(1):41-46. · 0.37 Impact Factor
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    ABSTRACT: Uremic restless legs syndrome (RLS) has been related to an enhanced mortality of hemodialysis (HD) patients. In the general population studies of this association have yielded inconsistent results. The aim of the present study was to re-evaluate the relationship of RLS and mortality in HD patients. We recorded the 3-year mortality in 579 HD patients after assessment for RLS symptoms. This population has been previously evaluated for the prevalence of RLS, according to the essential criteria of the International RLS Study Group. Mortality data were acquired from the national end-stage renal disease registry. Survival probability was calculated by the Kaplan-Meier method and analyzed by the log-rank test. For multivariate survival analysis, we implemented a Cox regression model. During the 3-year follow-up, we documented 118 deaths. Mortality was 15.6% in patients with RLS and 22.3% in patients without RLS (p = 0.079). According to the Cox regression analysis, there was no significant association between RLS and 3-year mortality, either in an age- and gender-adjusted model (hazard ratio [HR] = 0.772, 95% confidence interval [CI] = 0.488-1.219, p = 0.267) or in a multivariate adjusted model (HR = 0.667, 95% CI = 0.417-1.069, p = 0.092). Diagnosis of RLS according to the essential criteria of the International RLS Study Group does not seem to influence the 3-year mortality in HD patients. Our findings are in contrast to those in some previous reports, and reinforce the need for further studies of RLS and mortality in HD. Copyright © 2015 Elsevier B.V. All rights reserved.
    Sleep Medicine 06/2015; 16(9). DOI:10.1016/j.sleep.2015.04.023 · 3.15 Impact Factor
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    ABSTRACT: Introduction and Aims: Cardiac autonomic nervous system (ANS) dysfunction is a common feature in patients receiving hemodialysis (HD) therapy. Until today, spectral analysis of heart rate variability (HRV) is the most commonly used noninvasive method for the assessment of ANS activity. Pupillometry is a valid and low-cost method for the evaluation of ANS activity which reveals the sub-clinical defects in autonomic function of various diseases but also it has been proposed to be used as a complementary tool in the evaluation of cardiac autonomic function. Decreased HRV due to dysfunction of the cardiac autonomic function is a known complication of HD patients and is associated with an increased risk of ventricular arrhythmias and sudden death. However, the effect of HD on autonomic regulation of pupillary light reflex is not known. Furthermore, there are limited data available regarding alterations in HRV and pupillary light reflex during intradialytic exercise or without in HD patients. The aims of the current study were to investigate and compare the hemodynamic
    European Renal Association-European Dialysis and Transplant Association; 05/2015
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    ABSTRACT: Telomere shortening to a critical limit is associated with replicative senescence. This process is prevented by the enzyme telomerase. Oxidative stress and chronic inflammation are factors accelerating telomere loss. Chronic hemodialysis, typically accompanied by oxidative stress and inflammation, may be also associated with replicative senescence. To test this hypothesis, we determined telomere length and telomerase activity in peripheral blood mononuclear cells (PBMCs) in a cross-sectional study. Hemodialysis patients at the University Hospital Larissa and healthy controls were studied. Telomere length was determined by the TeloTAGGG Telomere Length Assay and telomerase activity by Telomerase PCR-ELISA (Roche Diagnostics GmbH, Mannheim, Germany). We enrolled 43 hemodialysis patients (17 females; age 65.0 ± 12.7 years) and 23 controls (six females; age 62.1 ± 15.7 years). Between the two groups, there was no difference in telomere length (6.95 ± 3.25 vs. 7.31 ± 1.96 kb; P = 0.244) or in telomerase activity (1.82 ± 2.91 vs. 2.71 ± 3.0; P = 0.085). Telomere length correlated inversely with vintage of hemodialysis (r = -0.332, P = 0.030). In hemodialysis patients, positive telomerase activity correlated with telomere length (r = 0.443, P = 0.030). Only age, and neither telomere length nor telomerase activity, was an independent survival predictor (hazard ratio 1.116, 95% confidence interval 1.009-1.234, P = 0.033). In this study, telomere length and telomerase activity in PBMCs are not altered in hemodialysis patients compared with healthy controls. Long duration of hemodialysis treatment is associated with telomere shortening and positive telomerase activity with an increased telomere length in PBMCs of hemodialysis patients. The underlying mechanism and clinical implications of our findings require further investigation. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
    Artificial Organs 04/2015; 39(9). DOI:10.1111/aor.12453 · 2.05 Impact Factor
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    ABSTRACT: Cognitive impairment is very often noted in patients with Chronic Kidney Disease (CKD). Even though, exercise is considered to be a quantifiable activity that improves cognition in animals and humans, it seems that few studies have examined the relationship between cognitive function and CKD from the perspective of physical activity and cognitive performance. Thus, this evidence based review summarizes the present level of knowledge regarding the effects of exercise training on cognitive function in CKD patients. A comprehensive literature search was conducted in PubMed and Scopus from May 2014 through June 2014, by using the Cochrane and PRISMA guidelines. Eligibility of the studies based on titles, abstracts and full-text articles was determined by two reviewers. Studies were selected using inclusion and exclusion criteria. We included only those studies that: assessed cognitive function in humans and animals using validated neuropsychological methods in chronic renal diseases patients; used exercise training protocols; addressed randomized control trials or controlled trials or clinical trials designed to evaluate cognitive impairment; and articles that were written in English. Studies were excluded when they concerned behavioral approaches and underpowered studies. According to the current review only a few studies have examined the issue of cognitive function in CKD patients. These studies indicate that these patients often exhibit cognitive impairment, which is highly associated with poor outcomes. It has been supported that exercise training can induce positive changes in brain metabolism favoring better scores in cognitive function in Chronic Kidney Disease patients although the physiological mechanisms, which explain the influence of physical activity on cognition, have focused on changes in neurotransmitters, neurotrophins and vasculature. Systematic exercise training seems to improve cognitive function in Chronic Kidney Disease patients but further research is warranted to further clarify the mechanisms involved. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Journal of Bodywork and Movement Therapies 04/2015; 19(3). DOI:10.1016/j.jbmt.2015.04.006
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    ABSTRACT: Ranolazine (RAN) and nicardipine (NIC) have been studied for their vasorelaxing effects but the combination of these agents against adrenergic vasoconstriction has not been tested. The present study aimed at investigating the vasorelaxing effect by the combination of the two agents on alpha1-adrenoceptor-mediated contraction on isolated rabbit aorta. Aortic rings were mounted for isometric tension recording in organ baths containing Krebs-Henseleit solution. Concentration-response curves of RAN (10–9 to 10–4 M), NIC (10–9 to 10–5 M), and RAN + NIC (3 × 10–6 M) were obtained in a cumulative manner using phenylephrine (PE, 2 × 10–6 M) as constrictor agent. The effective concentration (EC)50 values for RAN and NIC were 6.5 × 10–6 M and 1.4 × 10–5 M, respectively. The treatment of PE-precontracted aortic rings with either RAN or NIC up to 65 min revealed that both agents displayed a biphasic pattern of initial rising and late sustained phases of relaxation. At 35 min of incubation, RAN and NIC induced relaxation by 23 ± 3% and 14 ± 4%, respectively (N = 7, P = NS, RAN vs NIC); their combination resulted in a 34 ± 4% relaxation (N = 7; P < 0.01, RAN + NIC vs NIC). At 65 min the effect of NIC prevailed and tended to be closer to the values of the combination treatment (P < 0.01, RAN + NIC vs RAN). The results indicate that RAN at therapeutic concentrations exerts a significant additive vasorelaxing effect when combined with NIC in rabbit aorta.
    Acta cardiologica 04/2015; 70(2):157-162. DOI:10.2143/AC.70.2.3073506 · 0.65 Impact Factor
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    ABSTRACT: Specialty section: This article was submitted to Striated Muscle Physiology, a section of the journal Frontiers in Physiology Renal failure is accompanied by progressive muscle weakness and premature fatigue, in part linked to hypokinesis and in part to uremic toxicity. These changes are associated with various detrimental biochemical and morphological alterations. All of these pathological parameters are collectively termed uremic myopathy. Various interventions while helpful can't fully remedy the pathological phenotype. Complex mechanisms that stimulate muscle dysfunction in uremia have been proposed, and oxidative stress could be implicated. Skeletal muscles continuously produce reactive oxygen species (ROS) and reactive nitrogen species (RNS) at rest and more so during contraction. The aim of this mini review is to provide an update on recent advances in our understanding of how ROS and RNS generation might contribute to muscle dysfunction in uremia. Thus, a systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. While few studies met our criteria their findings are discussed making reference to other available literature data. Oxidative stress can direct muscle cells into a catabolic state and chronic exposure to it leads to wasting. Moreover, redox disturbances can significantly affect force production per se. We conclude that oxidative stress can be in part responsible for some aspects of uremic myopathy. Further research is needed to discern clear mechanisms and to help efforts to counteract muscle weakness and exercise intolerance in uremic patients.
    Frontiers in Physiology 04/2015; 1(6):30-102. DOI:10.3389/fphys.2015.00102 · 3.53 Impact Factor
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    ABSTRACT: Introduction and Aims: Chronic kidney disease (CKD) leads to muscle atrophy, metabolic disorders, diminished exercise capacity and fatigue. Complex mechanisms causing dysfunction have been proposed, and oxidative stress may be implicated. The presence of oxidative stress in CKD is evidenced by an overabundance of lipid, carbohydrate and protein oxidation products in blood and skeletal muscle of patients. The aim of this study was to evaluate the effects of uremia on skeletal muscle (psoas, soleus) and blood redox status in a rabbit model of renal insufficiency.
    ERA-EDTA; 01/2015
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    ABSTRACT: Hepatitis B virus (HBV) is a major global health problem. Despite the success of the general measures against blood transmitted infections in hemodialysis (HD) units, the prevalence of HBV infection among the HD patients is still high. Thus vaccination against HBV is indicating in this population. However, compared with the general population the seroprotection achieved in HD patients remains relatively low, at about 70%. In this review patient, HD procedure and vaccine-associated factors that affect the efficacy of HBV vaccination are analyzed. Also alternative routes of HBV vaccine administration as well as new and more immunogenic vaccine formulations are discussed. However, besides scientific progress, vigilance of HD physicians and staff regarding the general measures against the transmission of blood borne infections and the vaccination against HBV is also required for reducing the prevalence of this viral infection.
    World Journal of Gastroenterology 09/2014; 20(34):12018-12025. DOI:10.3748/wjg.v20.i34.12018 · 2.37 Impact Factor
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    ABSTRACT: Restless legs syndrome (RLS) affects almost one out of three end-stage renal disease patients. This review assesses the current treatment options of uremic RLS and its potential benefits of those treatments on quality of life parameters, cardiovascular mortality and survival. A systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. Fourteen studies met the inclusion criteria in which the international RLS study group criteria were used as the primary diagnostic tool. Both pharmacological and non-pharmacological approaches were found to reduce the severity of uremic RLS symptoms. Only four studies had reported changes on aspects related to quality of life while those changes were also associated with health benefits that resulted in reduced cardiovascular risk. The severity of uremic RLS symptoms can be ameliorated by using dopamine agonists and gabapentin, intravenous iron, exercise or supplementation with vitamins C and E, while some of those treatment benefits can be attenuated rapidly. There is a lack of strong evidence regarding the effects of the pharmacological approaches on quality of life and cardiovascular survival and mortality. In contrast exercise has been proven beneficial in both reducing the RLS symptoms’ severity score and improving the quality of life.
    Sleep Medicine Reviews 08/2014; 21. DOI:10.1016/j.smrv.2014.07.006 · 8.51 Impact Factor
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    ABSTRACT: Purpose: The relative effectiveness and tolerability of treatments for type 2 diabetes mellitus (T2DM) is not well understood because few randomized, controlled trials (RCTs) have compared these treatments directly. The purpose of the present study was to evaluate the relative effectiveness and tolerability of treatments of T2DM. Methods: We performed a network meta-analysis of available RCTs with pharmacologic interventions in T2DM and compared antidiabetic drugs and combination regimens with metformin (the reference drug). Glycemic control (proportion achieving HbA1c goal) and tolerability (risk of hypoglycemia) were the primary outcomes of interest. Direct and indirect relative effects (unadjusted) were expressed as odds ratios and 95% CIs. Findings: Eight treatments (glucagon-like peptide-1 [GLP-1] agonists plus metformin, sulfonylureas plus metformin, dipeptidyl peptidase-4 [DPP-4] inhibitors] plus metformin, colesevelan plus metformin, thiazolidinediones plus metformin, meglitinides plus metformin, α-glucosidase inhibitor plus metformin, and rosiglitazone monotherapy) outperformed metformin (direct effects). Triple combinations of GLP-1, thiazolinedione, insulin, metiglinide, or sulfonylureas added to a metformin backbone improved glycemic control (indirect effects). Higher risk of hypoglycemia was noted for sulfonylureas, α-glycosidases, and metiglinides when added to metformin (direct effects). Across indirect effects, only 17% of comparisons yielded less risk of hypoglycemia (70% were worse and 13% were comparable). Implications: Our results point out the relative superiority of 2- and 3-drug combination regimens over metformin and summarize treatment effects and tolerability in a comprehensive manner, which adds to our knowledge regarding T2DM treatment options.
    Clinical Therapeutics 08/2014; 36(10). DOI:10.1016/j.clinthera.2014.06.035 · 2.73 Impact Factor
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    ABSTRACT: Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immunity by inhibiting T-cell proliferation and altering glucose metabolism. Tumor suppressor p53 also alters these cellular processes towards the same direction. The effect of IDO on p53, and glucose metabolism was evaluated in alloreactive T-cells. Mixed lymphocyte reaction (MLR) performed in the presence or not of the IDO inhibitor, 1-DL-methyl-tryptophane (1-MT) and/or p53 inhibitor, pifithrin-α (PFT). Cell proliferation, glucose consumption and lactate production were assessed. 1-MT increased cell proliferation, glucose influx and lactate production, whereas PFT enhanced cell proliferation, glucose influx, leaving lactate production unaffected. In MLR-derived T-cells protein analysis revealed that IDO activated general control nonderepressible 2 (GCN2) kinase and induced p53, p53 phosphorylated at serine 15 (p-p53), and p21. In addition, both IDO and p53 decreased glucose transporter 1 (GLUT1), TP53-induced glycolysis and apoptosis regulator (TIGAR) and increased synthesis of cytochrome c oxidase 2 (SCO2). Also IDO reduced lactate dehydrogenase-A (LDH-A) and glutaminase 2 (GLS2), whereas p53 left them unaffected. Neither 1-MT nor PFT affected glucose-6-phosphate dehydrogenase (G6PD). Conclusively, in alloreactive T-cells, IDO increases p53 level, and both IDO and p53 inhibit cell proliferation, glucose consumption and glycolysis. Lactate production and glutaminolysis are also suppressed by IDO, but not by p53.
    International Immunology 07/2014; 26(12). DOI:10.1093/intimm/dxu077 · 2.54 Impact Factor
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    ABSTRACT: Vascular endothelial growth factor (VEGF), a cytokine that increases vascular permeability to water and proteins and induces angiogenesis, has been implicated in the development of pleural effusions. Inflammatory and malignant pleural effusions are rich in VEGF content while mesothelial cells produce and excrete VEGF. In this report we aimed at investigating by means of electrophysiology the direct effects of VEGF on the parietal and visceral sheep pleura as well as the type of receptors that mediate this effect. Our findings show that VEGF has a direct effect on the pleural mesothelium rendering it more permeable and this effect is mediated through the stimulation of VEGF receptor 2. Our findings shed more light to the role of VEGF in the pathogenesis of pleural effusions and provide functional evidence for a role of VEGFR2 on the pleural mesothelium that has never been studied before.
    Cytokine 06/2014; 69(2). DOI:10.1016/j.cyto.2014.06.014 · 2.66 Impact Factor
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    ABSTRACT: Abstract Non-dipping circadian blood pressure (BP) is a common finding in preeclampsia, accompanied by adverse outcomes. Melatonin plays pivotal role in biological circadian rhythms. This study investigated the relationship between melatonin secretion and circadian BP rhythm in preeclampsia. Cases were women with preeclampsia treated between January 2006 and June 2007 in the University Hospital of Larissa. Volunteers with normal pregnancy, matched for chronological and gestational age, served as controls. Twenty-four hour ambulatory BP monitoring was applied. Serum melatonin and urine 6-sulfatoxymelatonin levels were determined in day and night time samples by enzyme-linked immunoassays. Measurements were repeated 2 months after delivery. Thirty-one women with preeclampsia and 20 controls were included. Twenty-one of the 31 women with preeclampsia were non-dippers. Compared to normal pregnancy, in preeclampsia there were significantly lower night time melatonin (48.4 ± 24.7 vs. 85.4 ± 26.9 pg/mL, p < 0.001) levels. Adjustment for circadian BP rhythm status ascribed this finding exclusively to non-dippers (p < 0.01). Two months after delivery, in 11 of the 21 non-dippers both circadian BP and melatonin secretion rhythm reappeared. In contrast, in cases with retained non-dipping status (n = 10) melatonin secretion rhythm remained impaired: daytime versus night time melatonin (33.5 ± 13.0 vs. 28.0 ± 13.8 pg/mL, p = 0.386). Urinary 6-sulfatoxymelatonin levels were, overall, similar to serum melatonin. Circadian BP and melatonin secretion rhythm follow parallel course in preeclampsia, both during pregnancy and, at least 2 months after delivery. Our findings may be not sufficient to implicate a putative therapeutic effect of melatonin, however, they clearly emphasize that its involvement in the pathogenesis of a non-dipping BP in preeclampsia needs intensive further investigation.
    Renal Failure 06/2014; 36(7):1-7. DOI:10.3109/0886022X.2014.926216 · 0.94 Impact Factor
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    ABSTRACT: Variants of the interleukin-1β gene (IL1B) are implicated in the development of diabetic nephropathy (DN). The present candidate-gene association study was conducted to investigate the association between the IL1B C-511T variant and the risk of DN in a Caucasian population. The study population consisted of 173 cases (patients with type 2 diabetes mellitus [DM] and DN) and 186 controls (patients with DM free of DN). Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The PCR product was a 304-bp long DNA fragment of the IL1B gene promoter region, extending from position -702 to -398 and including the polymorphic AvaI site (at position -511). The magnitude of the overall association was tested using the generalized odds ratio (ORG) metric, a genetic model-free approach. The ORs (adjusted for effect modifiers) of the additive and co-dominant models were also estimated. The mode of inheritance was assessed using the degree of dominance index (h). There was a significant difference in the genotype distribution between the group of cases with DN compared with diseased controls free of DN (p=0.014). Analysis produced a significant ORG (ORG=1.74, 95% confidence interval [CI]=1.20-2.52), indicating that the risk of DN is significantly associated with the mutational load. The risk of developing DN is significantly enhanced in IL1B T allele carriers (dominant model, p=0.005) and in homozygotes (additive model, p=0.018) respectively. However, the recessive model for T allele (p=0.097) and the co-dominant model (p=0.085) produced non-significant results. Considering that the additive model was significant (OR=2.53, 95% CI=1.20-5.36) and the co-dominant is non-significant (OR=1.53, 95% CI=0.97-2.40), the mode of inheritance is complete "additiveness," with the degree of dominance being h=0. The findings provided evidence that the IL1B C-511T variant might be associated with development of DN.
    DNA and cell biology 05/2014; 33(7). DOI:10.1089/dna.2013.2204 · 2.06 Impact Factor
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    ABSTRACT: Disturbed iron homeostasis contributes to resistance to recombinant human erythropoietin (rHuEpo) in hemodialysis (HD) patients. Although increased hepcidin, which downregulates the iron exporter ferroportin, had been incriminated, such an association has not been confirmed. Albeit not universally accepted, it has been supported that in case of copper deficiency, decreased activity of multicopper oxidases induces endocytosis and degradation of ferroportin. Ferroportin in monocytes, serum copper, ceruloplasmin and markers of iron status were measured, and associations with rHuEpo resistance index (ERI) were evaluated. After a 4-week washout period from iron treatment, 34 HD patients and 20 healthy volunteers enrolled in the study. Ferroportin was assessed by means of Western blotting, copper colorimetrically, whereas ceruloplasmin with enzyme-linked immunosorbent assay. Hemoglobin, serum iron, ferritin and transferrin saturation (TSAT) were also measured. Ferroportin in monocytes of HD patients was decreased. Serum copper, ceruloplasmin, iron and TSAT were decreased. No correlation between copper or ceruloplasmin and ferroportin was detected. ERI was negatively correlated with ferroportin and all the markers of iron adequacy, but not with copper or ceruloplasmin. Although copper deficiency and decreased ferroportin are common in HD patients, copper might not play role in ferroportin level in monocytes and in iron metabolism in this population.
    International Urology and Nephrology 05/2014; 46(9). DOI:10.1007/s11255-014-0725-y · 1.52 Impact Factor
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    ABSTRACT: A 77-year-old man, 11 years under chronic hemodialysis treatment for chronic renal failure of unknown origin, presented with anterior chest pain, dyspnea with paradoxical breathing, and sternal instability after a simple fall from a standing height. Patient underwent three-vessel coronary artery bypass grafting 31 months ago. Computed tomography with three-dimensional volume rendering showed sternal nonunion with a great gap between the two halves of the sternum and at least one fracture in the left half of the sternum. A successful surgical repair followed. Patient suffered from severe secondary hyperparathyroidism for many years. Despite treatment with sevelamer, paricalcitol and cinacalcet, intact parathyroid hormone was 1682 pg/mL. During the last 5 years, serum intact parathyroid hormone remained steadily above 1000 pg/mL. Patient refused parathyroidectomy in the past. We assume that long-lasting severe hyperparathyroidism contributed to this rare and life-threatening complication of median sternotomy in our patient, due to the detrimental effect of hyperparathyroidism on bone metabolism and its association with increased incidence of bone fractures and defect in bone fracture healing.
    Hemodialysis International 04/2014; 18(3). DOI:10.1111/hdi.12153 · 1.24 Impact Factor

Publication Stats

2k Citations
428.92 Total Impact Points


  • 2002–2015
    • University of Thessaly
      • • Department of Nephrology
      • • School of Medicine
      • • Department of Internal Medicine
      Iolcus, Thessaly, Greece
  • 2005–2012
    • General University Hospital of Larissa
      Lárissa, Thessaly, Greece
  • 2011
    • Aristotle University of Thessaloniki
      Saloníki, Central Macedonia, Greece
  • 2009
    • Γενικό Νοσοκομείο Σερρών
      Seres, Central Macedonia, Greece
  • 1992–2002
    • RWTH Aachen University
      Aachen, North Rhine-Westphalia, Germany
  • 1996–2001
    • University Hospital RWTH Aachen
      • Department of Neurology
      Aachen, North Rhine-Westphalia, Germany