Antigone Siamopoulou
University of Ioannina
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Antigone Siamopoulou.
Acta Haematologica | 2010
Nikolaos Chaliasos; Anna Challa; Eleftheria Hatzimichael; Freideriki Koutsouka; Dimitrios K. Bourantas; Antonios P. Vlahos; Antigone Siamopoulou; Konstantinos L. Bourantas; Alexandros Makis
Background/Aim: The adipocytokines leptin and adiponectin represent a critical link between metabolism, immunity and chronic inflammation. A chronic vascular inflammatory state plays an important role in the pathophysiology of thalassaemia. We aimed to analyze the levels of these adipocytokines and determine any possible correlations with disease severity or vascular inflammation markers in beta-thalassaemia. Methods: Serum leptin, adiponectin, high-sensitivity C-reactive protein, endothelins, vascular adhesion molecule-1, intracellular adhesion molecule-1 and L- and E-selectin were measured in 28 beta-thalassaemia patients and compared with levels in healthy controls. Results: Leptin was significantly lower in patients compared to controls (2.23 ± 1.8 vs. 10.24 ± 5.78 µg/l; p = 0.0018), whereas adiponectin was elevated (11.75 ± 5.67 vs. 6.83 ± 2.75 µg/l; p = 0.009). For both adipocytokines, no correlations were found with characteristics such as age, gender, type of chelation, body mass index z score or haemoglobin. Leptin, but not adiponectin, was negatively correlated with ferritin (p = 0.032, r = –0.61). No correlations were found between leptin and the inflammation markers. However, adiponectin was positively correlated with endothelin-1 (p = 0.022, r = 0.63). Conclusions: Serum leptin is low in beta-thalassaemia, perhaps due to the toxic effect of iron overload on adipose tissue. Paradoxically, adiponectin levels are high and positively correlated with endothelin-1, raising questions about the pro- or anti-inflammatory role of this adipocytokine in beta-thalassaemia.
Anemia | 2013
Alexandros Makis; Nikolaos Chaliasos; Sapfo Alfantaki; Paraskevi Karagouni; Antigone Siamopoulou
Iron overload in hemoglobinopathies is secondary to blood transfusions, chronic hemolysis, and increased iron absorption and leads to tissue injury requiring the early use of chelating agents. The available agents are parenteral deferoxamine and oral deferiprone and deferasirox. There are limited data on the safety and efficacy of deferiprone at a very young age. The aim of our study was the presentation of data regarding the use of oral solution of deferiprone in 9 children (mean age 6.5, range 2–10) with transfusion dependent hemoglobinopathies (6 beta thalassemia major, 1 thalassemia intermedia, and 2 sickle cell beta thalassemia). The mean duration of treatment was 21.5 months (range 15–31). All children received the oral solution without any problems of compliance. Adverse reactions were temporary abdominal discomfort and diarrhea (1 child), mild neutropenia (1 child) that resolved with no need of discontinuation of treatment, and transient arthralgia (1 child) that resolved spontaneously. The mean ferritin levels were significantly reduced at the end of 12 months (initial 2440 versus final 1420 μg/L, P < 0.001). This small study shows that oral solution of deferiprone was well tolerated by young children and its use was not associated with major safety concerns. Furthermore, it was effective in decreasing serum ferritin.
Journal of Medical Case Reports | 2010
Alexandros Makis; Stavros Stavrou; Nikolaos Chaliasos; Aikaterini Zioga; Antonios P. Vlahos; Georgios Gaitanis; Antigone Siamopoulou; Ioannis D. Bassukas
IntroductionSweets syndrome characterized by fever, blood neutrophilia and inflammatory skin lesions, is rarely diagnosed in children. It presents in three clinical settings: classical Sweets syndrome, usually after a respiratory tract infection; malignancy-associated, frequently related to acute myelogeneous leukemia; and drug-induced. We present, to the best of our knowledge, the first case of a rotavirus -infection-related Sweets syndrome.Case presentationAn 18-month-old boy of Hellenic origin was referred to us with diarrhea, fever, neutrophilia, typical skin lesions, asymmetrical hip arthritis and oropharyngeal involvement. A skin biopsy confirmed the diagnosis. Thorough screening did not reveal any underlying systemic illness, except for the confirmation of an overt rotavirus infection. The syndrome responded promptly upon corticosteroid administration; no recurrence was observed.ConclusionBesides describing the connection of Sweets syndrome to a rotavirus infection, this case report is also a reminder that in a child presenting with a febrile papulo-nodular rash with neutrophilia Sweets syndrome should be included in the differential.
Journal of Interferon and Cytokine Research | 2010
Alexandros Makis; David Shipway; Eleftheria Hatzimichael; Emmanouil Galanakis; Dmitry Pshezhetskiy; Nikolaos Chaliasos; Justin Stebbing; Antigone Siamopoulou
Viral meningitis is characterized by cerebrospinal fluid (CSF) lymphocyte pleocytosis, although neutrophils may predominate in the early phase. The T helper 1 (Th1)/Th2 cytokine balance and expression of adhesion molecules seem to be involved in the CSF chemotaxis. We aimed to determine expression of cytokines and adhesion molecules in enteroviral meningitis. We investigated the serum and CSF levels of adhesion molecules (E-selectin, L-selectin, vascular cell adhesion molecule-1 [VCAM-1], and intracellular adhesion molecule-1 [ICAM-1]) and cytokines (interleukin-12 [IL-12] and IL-4) in 105 children during an outbreak of enteroviral meningitis. Diagnosis was confirmed with positive polymerase chain reaction (PCR) and/or serology for echovirus or Coxsackie virus, and matched with control subjects for clinical features but with negative PCR and/or serology. Apart from VCAM-1, the CSF levels of all investigated inflammatory molecules were significantly increased. In serum, sL-selectin and ICAM-1 levels were significantly higher than control subjects. Serum and CSF L-selectin, serum VCAM-1, and CSF IL-12 were all observed to be expressed in significantly higher levels in the neutrophil-dominant subgroup (72% had duration of symptoms <24 h) than in the lymphocyte-dominant group (87.5% had duration of symptoms >24 h). Serum and CSF ICAM-1 was found at significantly higher levels in the latter group. Evolving expression of adhesion molecules and cytokines indicates a shift from Th1 to Th2 immune responses as infection progresses.
Scandinavian Journal of Infectious Diseases | 2000
Emmanouil Galanakis; Evangelia Kritikou-Pliota; Christianna Pappa; Antigone Siamopoulou; Zoe L. Papadopoulou
The case of an otherwise well 9-y-old boy with fever, papular rash, jaundice and impaired liver function is presented. Streptococcus mitis sensitive to penicillin grew in blood culture. The boy had an excellent outcome. The clinical spectrum of viridans streptococci may be wider than currently anticipated, and Streptococcus mitis may cause septicaemia and hepatitis in immunocompetent individuals.The case of an otherwise well 9-y-old boy with fever, papular rash, jaundice and impaired liver function is presented. Streptococcus mitis sensitive to penicillin grew in blood culture. The boy had an excellent outcome. The clinical spectrum of viridans streptococci may be wider than currently anticipated, and Streptococcus mitis may cause septicaemia and hepatitis in immunocompetent individuals.
Journal of Pediatric Hematology Oncology | 2011
Alexandros Makis; Antonis Kattamis; Vassilios Grammeniatis; Polyxeni Sihlimiri; Haralambos Kotsonis; Andreas Iliadis; Antigone Siamopoulou; Nikolaos Chaliasos
Diamond-Blackfan anemia (DBA) is a rare, congenital, pure red blood cell aplasia owing to gene defects affecting the function of ribosomal proteins, essential for erythroid maturation. Iron overload is a serious complication of chronic transfusions, which may lead to cardiac toxicity and endothelial damage. We report a case of pulmonary embolism, observed after viper bite in a transfusion-dependent child with DBA without known inherited thrombophilic factors. Embolic events are uncommon after viper bites, which they usually cause consumption coagulopathy, resulting in hypocoagulable state. DBA has not been earlier correlated with thrombotic episodes. In our patient, we suggest an iron overload-induced hypercoagulability state, which in the presence of a procoagulant substance lead to the development of a thromboembolic event.
British Journal of Haematology | 2013
Alexandros Makis; Anna Challa; Eleftheria Hatzimichael; Evangelos Briasoulis; Antigone Siamopoulou; Nikolaos Chaliasos
Cory, S. & Adams, J.M. (2002) The Bcl2 family: regulators of the cellular life-or-death switch. Nature Reviews Cancer, 2, 647–656. Del Gaizo Moore, V., Brown, J.R., Certo, M., Love, T.M., Novina, C.D. & Letai, A. (2007) Chronic lymphocytic leukemia requires BCL2 to sequester prodeath BIM, explaining sensitivity to BCL2 antagonist ABT-737. The Journal of Clinical Investigation, 117, 112–121. Gottschalk, A.R., Boise, L.H., Oltvai, Z.N., Accavitti, M.A., Korsmeyer, S.J., Quintans, J. & Thompson, C.B. (1996) The ability of Bcl-x(L) and Bcl-2 to prevent apoptosis can be differentially regulated. Cell Death and Differentiation, 3, 113–118. Mason, K.D., Carpinelli, M.R., Fletcher, J.I., Collinge, J.E., Hilton, A.A., Ellis, S., Kelly, P.N., Ekert, P.G., Metcalf, D., Roberts, A.W., Huang, D.C. & Kile, B.T. (2007) Programmed anuclear cell death delimits platelet life span. Cell, 128, 1173–1186. Oltersdorf, T., Elmore, S.W., Shoemaker, A.R., Armstrong, R.C., Augeri, D.J., Belli, B.A., Bruncko, M., Deckwerth, T.L., Dinges, J., Hajduk, P.J., Joseph, M.K., Kitada, S., Korsmeyer, S.J., Kunzer, A.R., Letai, A., Li, C., Mitten, M.J., Nettesheim, D.G., Ng, S., Nimmer, P.M., O’Connor, J.M., Oleksijew, A., Petros, A.M., Reed, J.C., Shen, W., Tahir, S.K., Thompson, C.B., Tomaselli, K.J., Wang, B., Wendt, M.D., Zhang, H., Fesik, S.W. & Rosenberg, S.H. (2005) An inhibitor of Bcl-2 family proteins induces regression of solid tumours. Nature, 435, 677–681. Park, C.M., Bruncko, M., Adickes, J., Bauch, J., Ding, H., Kunzer, A., Marsh, K.C., Nimmer, P., Shoemaker, A.R., Song, X., Tahir, S.K., Tse, C., Wang, X., Wendt, M.D., Yang, X., Zhang, H., Fesik, S.W., Rosenberg, S.H. & Elmore, S.W. (2008) Discovery of an orally bioavailable small molecule inhibitor of prosurvival B-cell lymphoma 2 proteins. Journal of Medicinal Chemistry, 51, 6902–6915. Roberts, A.W., Seymour, J.F., Brown, J.R., Wierda, W.G., Kipps, T.J., Khaw, S.L., Carney, D.A., He, S.Z., Huang, D.C., Xiong, H., Cui, Y., Busman, T.A., McKeegan, E.M., Krivoshik, A.P., Enschede, S.H. & Humerickhouse, R. (2012) Substantial susceptibility of chronic lymphocytic leukemia to BCL2 inhibition: results of a phase I study of navitoclax in patients with relapsed or refractory disease. Journal of Clinical Oncology, 30, 488– 496. Souers, A.J., Leverson, J.D., Boghaert, E.R., Ackler, S.L., Catron, N.D., Chen, J., Dayton, B.D., Ding, H., Enschede, S.H., Fairbrother, W.J., Huang, D.C., Hymowitz, S.G., Jin, S., Khaw, S.L., Kovar, P.J., Lam, L.T., Lee, J., Maecker, H.L., Marsh, K.C., Mason, K.D., Mitten, M.J., Nimmer, P.M., Oleksijew, A., Park, C.H., Park, C.M., Phillips, D.C., Roberts, A.W., Sampath, D., Seymour, J.F., Smith, M.L., Sullivan, G.M., Tahir, S.K., Tse, C., Wendt, M.D., Xiao, Y., Xue, J.C., Zhang, H., Humerickhouse, R.A., Rosenberg, S.H. & Elmore, S.W. (2013) ABT-199, a potent and selective BCL-2 inhibitor, achieves antitumor activity while sparing platelets. Nature Medicine, 19, 202–208. Vogler, M., Dinsdale, D., Sun, X.M., Young, K.W., Butterworth, M., Nicotera, P., Dyer, M.J. & Cohen, G.M. (2008) A novel paradigm for rapid ABT-737-induced apoptosis involving outer mitochondrial membrane rupture in primary leukemia and lymphoma cells. Cell Death and Differentiation, 15, 820–830. Vogler, M., Furdas, S.D., Jung, M., Kuwana, T., Dyer, M.J. & Cohen, G.M. (2010) Diminished sensitivity of chronic lymphocytic leukemia cells to ABT-737 and ABT-263 due to albumin binding in blood. Clinical Cancer Research, 16, 4217–4225.
Journal of Infection | 2005
Alexandros Makis; Emmanouil Galanakis; Eleftheria Hatzimichael; Zoe L. Papadopoulou; Antigone Siamopoulou; Konstantinos L. Bourantas
European Journal of Pediatrics | 2013
Meropi Tzoufi; Alexandros Makis; Nikolaos Chaliasos; Iliada Nakou; Ekaterini Siomou; Agathoklis Tsatsoulis; Anastasia Zikou; Maria I. Argyropoulou; Jean Paul Bonnefont; Antigone Siamopoulou
Pediatric Infectious Disease Journal | 2004
Nikolaos Daskas; Efstathios Aggelopoulos; Meropi Tzoufi; Paraskevi Kosta; Antigone Siamopoulou; Maria I. Argyropoulou