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Dive into the research topics where Ioannis Paraskevaidis is active.

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Featured researches published by Ioannis Paraskevaidis.


Circulation | 2008

Inhibition of Interleukin-1 by Anakinra Improves Vascular and Left Ventricular Function in Patients With Rheumatoid Arthritis

Ignatios Ikonomidis; John Lekakis; Maria Nikolaou; Ioannis Paraskevaidis; Ioanna Andreadou; Theophania Kaplanoglou; Pelagia Katsimbri; Grigorios Skarantavos; Panayiotis N. Soucacos; Dimitrios Th. Kremastinos

Background— Interleukin-1 increases nitrooxidative stress. We investigated the effects of a human recombinant interleukin-1a receptor antagonist (anakinra) on nitrooxidative stress and vascular and left ventricular function. Methods and Results— In an acute, double-blind trial, 23 patients with rheumatoid arthritis were randomized to receive a single injection of anakinra (150 mg SC) or placebo and, after 48 hours, the alternative treatment. At baseline and 3 hours after the injection, we assessed (1) coronary flow reserve, aortic distensibility, systolic and diastolic (Em) velocity of the mitral annulus, and E to Em ratio (E/Em) using echocardiography; (2) flow-mediated, endothelium-dependent dilation of the brachial artery; and (3) malondialdehyde, nitrotyrosine, interleukin-6, endothelin-1, and C-reactive protein. In a chronic, nonrandomized trial, 23 patients received anakinra and 19 received prednisolone for 30 days, after which all indices were reassessed. Compared with baseline, there was a greater reduction in malondialdehyde, nitrotyrosine, interleukin-6, and endothelin-1 and a greater increase in flow-mediated dilation, coronary flow reserve, aortic distensibility, systolic velocity of mitral annulus, and E/Em after anakinra than after placebo (malondialdehyde −25% versus 9%; nitrotyrosine −38% versus −11%; interleukin-6 −29% versus 0.9%; endothelin-1 −36% versus −11%; flow-mediated dilation 45% versus −9%; coronary flow reserve 29% versus 4%; and aortic distensibility 45% versus 2%; P<0.05 for all comparisons). After 30 days of treatment, the improvement in biomarkers and in vascular and left ventricular function was greater in the anakinra group than in the prednisolone group (P<0.05). Conclusions— Interleukin-1 inhibition improves vascular and left ventricular function and is associated with reduction of nitrooxidative stress and endothelin.


Heart | 2006

Increased C reactive protein and cardiac enzyme levels after coronary stent implantation. Is there protection by remote ischaemic preconditioning

Efstathios K. Iliodromitis; Stamatis Kyrzopoulos; Ioannis Paraskevaidis; Kyriacos Kolocassides; Stamatis Adamopoulos; George Karavolias; Dimitrios Th. Kremastinos

Aim: To investigate whether remote ischaemic preconditioning (RIPC) can attenuate the inflammatory response and enzyme leakage that can occur after uncomplicated routine percutaneous coronary intervention (PCI). Methods: 41 consecutive normotensive patients with stable angina and single-vessel disease were assigned to be exposed to RIPC (n = 20) or not (control group; n = 21) before elective PCI with stent implantation. RIPC was induced by three cycles of 5-min ischaemia–reperfusion of both upper limbs (inflation/deflation of blood pressure cuff). C reactive protein (CRP), creatine phosphokinase (CK), CK cardiac isoenzyme (CK-MB) and troponin I (TNI) were serially measured for 48 h. Results: No difference in baseline values was observed between the groups. The CRP rose significantly (p<0.001) and at 48 h was similarly increased (>fourfold) in both groups (15.7 (2.6) v 14.0 (3.3) mg/l, RIPC v control; p = NS). However, sub-group analysis on the basis of statin use showed that the highest rise was in the group of patients with RIPC not taking statins and was significantly greater than in patients with RIPC taking statins (23.8 (3.71) v 11.4 (3.0) mg/l, respectively, p<0.01). Both CK-MB and TNI leakage were raised (slightly but significantly) after PCI in controls at 24 h compared with baseline values. However, this small rise was significantly worse after RIPC (CK-MB, 1.33 (0.27) v 3.57 (0.97) ng/ml, p<0.01; TNI, 0.255 (0.059) v 0.804 (0.232) ng/ml, p<0.05, respectively at 24 h). The increase was more marked in the RIPC subgroup not taking statins. Conclusions: RIPC does not reduce, but exacerbates, the enzyme and TNI release from the heart after single-vessel angioplasty with stent. Furthermore, the increased circulating CRP remains raised. It seems that there is an enhanced inflammatory response after RIPC in the absence of statin treatment.


European Journal of Haematology | 2005

A comparison of magnetic resonance imaging and cardiac biopsy in the evaluation of heart iron overload in patients with β‐thalassemia major

Sophie Mavrogeni; Vyron Markussis; Loukas Kaklamanis; Dimitrios Tsiapras; Ioannis Paraskevaidis; George Karavolias; Markisia Karagiorga; Marouso Douskou; Dennis V. Cokkinos; Dimitrios Th. Kremastinos

Abstract:  Objectives: To apply magnetic resonance imaging (MRI) for the assessment of myocardial iron deposition in patients with β‐thalassemia and compare the results with cardiac biopsy data. Background: Myocardial iron accumulation is the main cause for cardiac complications in β‐thalassemia. Methods: Twenty‐five consecutive thalassemic patients were studied using a 0.5‐T (Tesla) system, ECG‐gated, with echo time (TE) = 17–68 ms. T2 relaxation time of the interventricular septum was calculated assuming simple monoexponential decay. A heart T2 relaxation time value of 32 ms was used for the discrimination between high and low iron deposition. Heart biopsy was performed within a week after the MRI study. Patients with stainable iron in more than 50% of the myofibrils were graded as having severe iron deposition. A serum ferritin level below 2000 ng/mL was considered as an indication of successful chelation. Results: Seven of the 25 patients had heart biopsy indicative of low iron deposition (Group L) and the remaining 18 patients had heart biopsy indicative of high iron deposition (Group H). T2 relaxation time of the heart (T2H) was lower in Group H compared to Group L (31.5 ± 3.9 (range: 28–40) ms vs. 35.7 ± 3.7 (range: 29–40) ms, P = 0.026). The T2H was in agreement with heart biopsy in 86% of the patients in Group L and in 78% of the patients in Group H (overall agreement 80%). Similarly, serum ferritin levels were in agreement with heart biopsy in 28% and 88%, respectively (overall agreement 72%). In Group L, MRI was in better agreement with biopsy compared to serum ferritin (86% vs. 28%, P < 0.05). A receiver operating characteristic curve (ROC) analysis confirmed that a T2 relaxation time of 32 ms had the highest discriminating ability for the corresponding biopsy outcome. Conclusions: Heart T2 relaxation time appears in agreement with cardiac biopsy, both in high and low iron deposition, and may become a useful non‐invasive index in β‐thalassemia.


European Heart Journal | 2003

Effects of growth hormone on circulating cytokine network, and left ventricular contractile performance and geometry in patients with idiopathic dilated cardiomyopathy

Stamatis Adamopoulos; John Parissis; Ioannis Paraskevaidis; Dimitrios Karatzas; Efthimios Livanis; Michael Georgiadis; George Karavolias; Dimitrios Mitropoulos; Dimitrios Degiannis; Dimitrios Th. Kremastinos

BACKGROUND Recent experimental and clinical data indicate that abnormal central and peripheral immune reactions contribute to the progression of chronic heart failure, and that immunomodulation may be an important therapeutic approach in this syndrome. Aims We sought to study the effects of growth hormone (GH) administration on circulating pro-inflammatory/anti-inflammatory cytokine balance, and to investigate whether these GH-induced immunomodulatory effects are associated with the improvement of left ventricular (LV) contractile performance in idiopathic dilated cardiomyopathy (DCM) patients. METHODS Plasma pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF) and its soluble receptor (sGM-CSFR), chemotactic cytokine macrophage chemoattractant protein-1 (MCP-1), soluble adhesion molecules intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1), and, finally, anti-inflammatory cytokines interleukin-10 (IL-10) and transforming growth factor-beta2 (TGF-beta2) were measured (ELISA method) in 12 patients with DCM (NYHA class III; LV ejection fraction: 23.6+/-1.7%) before and after a 3-month subcutaneous administration of GH 4IU every other day (randomized crossover design). Peak oxygen uptake (VO2 max), LV dimensions, LV mass index, end-systolic wall stress (ESWS), mean velocity of circumferential fibre shortening (Vcfc), and contractile reserve (change of ratio Vcfc/ESWS after dobutamine administration) were also determined at the same period. RESULTS Treatment with GH produced a significant reduction in plasma TNF-alpha (7.8+/-1.1 vs 5.5+/-0.9pg/ml, P=0.013), IL-6 (5.7+/-0.5 vs 4.7+/-0.4pg/ml, P=0.043), GM-CSF (27.3+/-1.7 vs 23.3+/-1.8pg/ml, P=0.042), sGM-CSFR (4.0+/-0.4 vs 3.2+/-0.4ng/ml, P=0.039), MCP-1 (199+/-5 vs 184+/-6pg/ml, P=0.048), sICAM-1 (324+/-34 vs 274+/-27ng/ml, P=0.008) and sVCAM-1 (1238+/-89 vs 1043+/-77ng/ml, P=0.002) in DCM patients. A significant increase in ratios IL-10/TNF-alpha (1.9+/-0.3 vs 3.5+/-0.9, P=0.049), IL-10/IL-6(2.6+/-0.6 vs 3.2+/-0.5, P=0.044) and TGF-beta2/TNF-alpha (3.1+/-0.6 vs 4.4+/-0.6, P=0.05) was alsofound with GH therapy. A significant reduction in ESWS (841+/-62 vs 634+/-48gr/cm(2), P=0.0026) and LV end-systolic volume index (LVESVI, 128+/-12 vs 102+/-12ml, P=0.035) as well as a significant increase in posterior wall thickness (PWTH, 9.2+/-0.5 vs 10.3+/-0.6mm, P=0.034), contractile reserve (0.00029+/-0.0001 vs 0.00054+/-0.0001circ*cm(2)/gr*s, P=0.00028) and VO2max (15.3+/-0.7 vs 17.1+/-0.9ml/kg/min, P=0.002) were observed after GH administration. Good correlations were found between GH-induced increase in contractile reserve and the increases in VO2max (r=0.63, P=0.028), IL-10/TNF-alpha (r=0.69, P=0.011) and TGF-beta2/TNF-alpha (r=0.58, P=0.046) ratios, as well as the reduction in plasma TNF-alpha levels (r=-0.86, P=0.0004). CONCLUSIONS GH administration modulates beneficially circulating cytokine network and soluble adhesion molecules in patients with DCM, whilst enhancing contractile reserve and diminishing LV volumes. These GH-induced anti-inflammatory effects may be associated with the improvement in LV contractile performance and exercise capacity as well as with the reverse of LV remodelling of patients with DCM.


American Journal of Hypertension | 2008

Incremental Value of Pulse Wave Velocity in the Determination of Coronary Microcirculatory Dysfunction in Never-treated Patients With Essential Hypertension

Ignatios Ikonomidis; John Lekakis; Costas G. Papadopoulos; Helen Triantafyllidi; Ioannis Paraskevaidis; Georgia Georgoula; Stavros Tzortzis; Ioanna Revela; Dimitrios Th. Kremastinos

BACKGROUND Coronary microcirculation is disturbed in essential hypertension. We investigated whether arterial stiffness determines coronary flow reserve (CFR) in hypertensive patients. METHODS We examined 100 never-treated hypertensives and 20 healthy controls. We measured (i) carotid-to-femoral pulse wave velocity (PWV); (ii) Systolic (V (s)) and diastolic (V (d)) coronary flow velocity, time integral (V (TI)-V (d)) of diastolic velocity and CFR after adenosine by transthoracic echocardiography; (iii) ratio of E wave from mitral inflow to Em of mitral annulus, as an index of left ventricular (LV) diastolic pressures using tissue Doppler; (iv) carotid intima-media thickness (IMT), as an index of vascular damage; and (v) 24-h blood pressure parameters using ambulatory blood pressure monitoring. RESULTS Patients had abnormal PWV, IMT, E/Em, resting V (d)/V (s), and CFR than controls (P < 0.05). In hypertensives, PWV was related to abnormal IMT and E/Em which in turn were related to reduced CFR (P < 0.05). PWV and E/Em were independent determinants of CFR and V (d)/V (s) (P < 0.05) in hypertensives. When added to a model including age, sex, smoking, LV mass (LVM), heart rate, 24-h systolic blood pressure (SBP), and E/Em, PWV had an incremental value in the determination of CFR (r (2) change from 0.25 to 0.46, P < 0.01). PWV >10.7 m/s predicted a CFR <2 with 79 and 75% and a CFR <2.6 with 83 and 82% sensitivity and specificity, respectively, using adjusted-receiver operating characteristic curve (ROC) analysis. CONCLUSIONS Elevated LV diastolic compressive forces on coronary microcirculation and the presence of generalized vascular damage may explain the association between PWV and CFR. PWV has an incremental value in the determination of impaired coronary microcirculation in hypertensive patients.


Circulation-cardiovascular Imaging | 2014

Increased benefit of interleukin-1 inhibition on vascular function, myocardial deformation, and twisting in patients with coronary artery disease and coexisting rheumatoid arthritis.

Ignatios Ikonomidis; Stavros Tzortzis; Ioanna Andreadou; Ioannis Paraskevaidis; Chrysoula Katseli; Pelagia Katsimbri; George Pavlidis; John Parissis; Dimitrios Th. Kremastinos; Maria Anastasiou-Nana; John Lekakis

Background—We investigated the effects of anakinra, an interleukin-1 receptor antagonist, on coronary and left ventricular function in coronary artery disease (CAD) patients with rheumatoid arthritis. Methods and Results—In a double-blind crossover trial, 80 patients with rheumatoid arthritis (60 with CAD and 20 without) were randomized to a single injection of anakinra or placebo and after 48 hours to the alternative treatment. At baseline and 3 hours after treatment, we assessed (1) flow-mediated dilation of brachial artery; (2) coronary flow reserve, ejection fraction, systemic arterial compliance, and resistance by echocardiography; (3) left ventricular global longitudinal and circumferential strain, peak twisting, untwisting velocity by speckle tracking; and (4) interleukin-1&bgr;, nitrotyrosine, malondialdehyde, protein carbonyl, and Fas/Fas ligand levels. At baseline, patients with CAD had 3-fold higher interleukin-1&bgr;, protein carbonyl, higher nitrotyrosine, malondialdehyde, and Fas/Fas ligand than non-CAD (P<0.05). After anakinra, there was a greater improvement of flow-mediated dilation (57±4% versus 47±5%), coronary flow reserve (37±4% versus 29±2%), arterial compliance (20±18% versus 2±17%), resistance (−11±19% versus 9±21%), longitudinal strain (33±5% versus 18±2%), circumferential strain (22±5% versus 13±5%), peak twisting (30±5% versus 12±5%), untwisting velocity (23±5% versus 13±5%), ejection fraction (12±5% versus 0.5±5%), apoptotic and oxidative markers, and, in particular, of protein carbonyl (35±20% versus 14±9%) in CAD than in non-CAD patients (P<0.01). No changes in the examined markers were observed after placebo. Conclusions—Interleukin-1 inhibition causes a greater improvement in endothelial, coronary aortic function in addition to left ventricular myocardial deformation and twisting in rheumatoid arthritis patients with CAD than in those without. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01566201.


Heart | 2008

Clinical and prognostic implications of self-rating depression scales and plasma B-type natriuretic peptide in hospitalised patients with chronic heart failure

John Parissis; Maria Nikolaou; Dimitrios Farmakis; Vassiliki Bistola; Ioannis Paraskevaidis; Stamatios Adamopoulos; Gerasimos Filippatos; Dimitrios Th. Kremastinos

Background: Depression is common among patients with chronic heart failure (CHF) and has been independently associated with a poorer prognosis. Purpose: This study evaluated the clinical and prognostic value of depression scales (Beck Depression Inventory (BDI), Zung Self-rating Depression Scale (Zung SDS)) along with plasma B-type natriuretic peptide (BNP) in CHF. Methods: 155 hospitalised CHF patients (ejection fraction 26.9% (SD 6.4%)) were studied by depression (BDI, Zung SDS) and functional questionnaires (Kansas City Cardiomyopathy Questionnaire (KCCQ), Duke Activity Status Index (DASI)), BNP and 6-minute walk test (6MWT). Patients were followed for 6 months for cardiovascular events, including death from any cause or rehospitalisation for CHF decompensation. Results: Seventy-six (49%) patients with depressive symptoms, as estimated by both scales, had significantly lower DASI and KCCQ scores (13.2 (SD 9.9) vs 23.6 (SD 13.0) and 26.6 (SD 15.0) vs 45.0 (SD 17.0), respectively; p<0.001), higher BNP (921 (SD 889) vs 439 (SD 267) pg/ml, p = 0.001) and reduced 6MWT (270 (SD 130) vs 337 (SD 133); p<0.001). According to logistic regression analysis, Zung SDS and BNP were independently associated with adverse clinical outcomes; values of Zung SDS ⩾40 and of BNP ⩾290 pg/ml predicted future events with a sensitivity of 82% and 94% and a specificity of 45% and 46%, respectively. The combination of Zung SDS plus BNP had an additive prognostic value, predicting events with a sensitivity of 77% and a specificity of 70% (event-free survival: Zung <40 and BNP <290 pg/ml; 170 (SD 9) days; Zung ⩾40 and BNP <290 pg/ml, 159 (SD 14) days; Zung <40 and BNP ⩾290 pg/ml, 118 (SD 15) days; Zung ⩾40 and BNP ⩾290 pg/ml, 73 (SD 8) days, p<0.001). Conclusions: CHF patients with depressive symptoms have impaired physical activity, associated with excessive neurohormonal activation. Among the studied scales, Zung SDS seemed to independently predict clinical outcome, especially in patients with increased plasma BNP concentration. Hence, the combination of those two modalities provides a practical means for risk stratification in CHF.


Heart Failure Reviews | 2009

Levosimendan: from basic science to clinical practice

John Parissis; Pinelopi Rafouli-Stergiou; Ioannis Paraskevaidis; Alexandre Mebazaa

Levosimendan is a new cardiac enhancer that exerts positive inotropic effects on the failing heart mediated by calcium sensitization of contractile proteins as well as peripheral vasodilatory effects mediated by opening of ATP-sensitive potassium channels in vascular smooth-muscle cells. Levosimendan is the most well-studied calcium sensitizer in the real clinical practice, producing greater hemodynamic and symptomatic improvement in patients with acute heart failure syndromes (AHFS) than those with traditional inotropes. Immunomodulatory and anti-apoptotic properties of levosimendan may be an additional biologic mechanism that prevents further cytotoxic and hemodynamic consequences of abnormal immune and neurohormonal responses in AHFS. Recent mortality trials showed that levosimendan does not improve short- and long-term prognosis in AHFS in comparison to dobutamine or placebo. However, in patients with a previous history of CHF and on beta-blocker on admission, levosimendan seems to have a beneficial effect on short-term mortality. According to the recent guidelines of the European Society of Cardiology, levosimendan is indicated in patients with symptomatic low cardiac output HF secondary to cardiac systolic dysfunction without severe hypotension (Class IIa, Level of Evidence B).


European Journal of Preventive Cardiology | 2008

Effects of darbepoetin-alpha on quality of life and emotional stress in anemic patients with chronic heart failure.

Kallirrhoe Kourea; John Parissis; Dimitrios Farmakis; Ioannis Paraskevaidis; Fotios Panou; Gerasimos Filippatos; Dimitrios Th. Kremastinos

Objective Anemia is a frequent comorbidity in chronic heart failure (CHF) adversely affecting patients’ prognosis. Erythropoietin seems to improve exercise capacity in CHF patients. This study investigates the effects of recombinant human erythropoietin analog darbepoetin-α on quality of life and emotional stress, evaluated by relevant questionnaires in patients with CHF and anemia. Methods Forty-one CHF patients [New York Heart Association class: II-III; left ventricular (LV) ejection fraction (EF) ≤40%; hemoglobin < 12.5 g/dl; serum creatinine < 2.5 mg/dl] were randomized (1:1) to receive either 3-month darbepoietin-α at 1.5 μg/Kg every 20 days plus iron orally (n = 21) or placebo plus iron orally (n = 20). Echocardiographic LVEF, questionnaires addressing quality of life (Kansas City Cardiomyopathy Questionnaire, functional and overall, Dukes Activity Status Index) and emotional stress [Zung self-rating depression scale (SDS), Beck Depression Inventory], as well as plasma b-type natriuretic peptide and 6-min walking distance (6MWT as a marker of exercise capacity) were assessed at baseline and posttreatment. Results A significant improvement in LVEF (32 ± 6 from 26 ± 6%, P < 0.001), 6MWT (274 ± 97 from 201 ± 113m, P < 0.01), hemoglobin (12.8 ± 1.4 from 10.9 ± 1.0 g/dl, P < 0.001) and plasma b-type natriuretic peptide (517 ± 579 from 829 ± 858 pg/ml, P = 0.002) was observed posttreatment only in darbepoetin-treated group. Kansas City Cardiomyopathy Questionnaire functional (78 ± 14 from 57 ± 24%, P < 0.01) and overall (68 ± 20 from 47 ± 22, P < 0.001), Dukes Activity Status Index (19 ± 11 from 14 ± 9, P < 0.05), Zung SDS (38 ± 10 from 47 ± 11, P < 0.05) and Beck Depression Inventory (11 ± 9 from 16 ± 10, P < 0.05) scores also improved in darbepoetin-treated patients, whereas they remain unchanged in the placebo group except for the Zung SDS which worsened (P≤0.05). A significant correlation between drug-induced percent changes in 6MWT and Zung SDS (r = –0.627, P < 0.05) was also observed. Conclusions Darbepoetin-α improves quality of life and emotional stress in CHF patients with anemia, with a parallel increase in exercise capacity.


International Journal of Cardiology | 1994

Does passive leg raising increase cardiac performance? A study using Doppler echocardiography

Zenon S. Kyriakides; Andreas Koukoulas; Ioannis Paraskevaidis; Dimitrios Chrysos; Dimitrios Tsiapras; Christos Galiotos; Dimitrios Th. Kremastinos

Passive leg raising is commonly used for the initial treatment of hypovolemic shock. However, there are many reports which have pointed out that it does not produce significant autotransfusion effect. We tried to evaluate the effects of passive leg raising on the cardiovascular performance in coronary artery disease patients in stable condition. We studied 31 patients of 51 +/- 10 years. Two M-mode echocardiographic and continuous wave Doppler studies of aortic flow were obtained. The first was performed while the patient was lying on the left side and the second after passive leg elevation. Left ventricular end-diastolic dimension increased by 0.40 +/- 0.82 cm (P = 0.007), fractional shortening by 2.5 +/- 6% (P = 0.01), peak aortic blood velocity by 5 +/- 14 cm/s (P = 0.02), and velocity time integral by 1.7 +/- 3.0 cm (P = 0.0007). From the above it is concluded that passive leg elevation really does increase preload, and consequently cardiac performance, by the classical Frank-Staring relationship in normovolemic coronary artery disease patients.

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Dimitrios Th. Kremastinos

National and Kapodistrian University of Athens

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John Parissis

National and Kapodistrian University of Athens

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Ignatios Ikonomidis

National and Kapodistrian University of Athens

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Gerasimos Filippatos

National and Kapodistrian University of Athens

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John Lekakis

National and Kapodistrian University of Athens

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Dimitrios Farmakis

National and Kapodistrian University of Athens

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Efstathios K. Iliodromitis

National and Kapodistrian University of Athens

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Maria Anastasiou-Nana

National and Kapodistrian University of Athens

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Maria Nikolaou

National and Kapodistrian University of Athens

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