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Featured researches published by N. Papadopoulos.


Theoretical Biology and Medical Modelling | 2005

Human embryonal epithelial cells of the developing small intestinal crypts can express the Hodgkin-cell associated antigen Ki-1 (CD30) in spontaneous abortions during the first trimester of gestation

D. Tamiolakis; J. Venizelos; Maria Lambropoulou; Silva Nikolaidou; Sophia Bolioti; Maria Tsiapali; Dionysios Verettas; Panagiotis Tsikouras; Athanasios Chatzimichail; N. Papadopoulos

BackgroundKi-1 (CD30) antigen expression is not found on peripheral blood cells but its expression can be induced in vitro on T and B lymphocytes by viruses and lectins. Expression of CD30 in normal tissues is very limited, being restricted mainly to a subpopulation of large lymphoid cells; in particular, cells of the recently described anaplastic large cell lymphoma (ALCL), the Reed-Sternberg (RS) cells of Hodgkins lymphoma and scattered large parafollicular cells in normal lymphoid tissues. More recent reports have described CD30 expression in non-hematopoietic and malignant cells such as cultured human macrophages, human decidual cells, histiocytic neoplastic cells, mesothelioma cells, embryonal carcinoma and seminoma cells.ResultsWe investigated the immunohistochemical expression of CD30 antigen in 15 paraffin-embedded tissue samples representing small intestines from fetuses after spontaneous abortion in the 8th, 10th and 12th weeks using the monoclonal antibody Ki-1. Hormones had been administered to all our pregnant women to support gestation. In addition, a panel of monoclonal antibodies was used to identify leukocytes (CD45/LCA), B-lymphocytes (CD20/L-26) and T-lymphocytes (CD3). Our findings were correlated with those obtained simultaneously from intestinal tissue samples obtained from 15 fetuses after therapeutic or voluntary abortions.ConclusionsThe results showed that: (1) epithelial cells in the developing intestinal crypts express the CD30 (Ki-1) antigen; (2) CD30 expression in these epithelial cells is higher in cases of hormonal administration than in normal gestation. In the former cases (hormonal support of gestation) a mild mononuclear intraepithelial infiltrate composed of CD3 (T-marker)-positive cells accompanies the CD30-positive cells.


Pathology & Oncology Research | 2005

An unusual case of posttransplant peritoneal primary effusion lymphoma with T-cell phenotype in a HIV-negative female, not associated with HHV-8

Ioannis Venizelos; D. Tamiolakis; Maria Lambropoulou; S. Nikolaidou; Sophia Bolioti; Hlias Papadopoulos; N. Papadopoulos

Primary effusion lymphoma (PEL) is a recently individualized form of non-Hodgkin’s lymphoma (WHO classification) that mainly develops in HIV infected males, more frequently in homosexuals and advanced stages of the disease (total CD4+ lymphocyte count below 100–200/μL). Occasionally, it appears in other immunodepressive states (such as solid organs transplant period) and even, although very rarely, in immunocompetent patients. From a pathogenetic point of view, PEL has been related to Kaposi’s sarcoma associated herpes virus (also named human herpesvirus 8, HHV-8), an etiological factor of Kaposi’s sarcoma. The relative infrequency of this disease, the absence of wide casuistics allowing a better characterization, and its unfavorable outcome support the need of a deeper knowledge. We present here the clinical-biological findings of a patient, HIV -seronegative, who was diagnosed with peritoneal PEL of T-cell origin, and not HHV-8-associated, five years after renal transplantation.


Leukemia & Lymphoma | 2005

Primary gastric Hodgkin's lymphoma: A case report and review of the literature

I Venizelos; Tamiolakis D; S Bolioti; S Nikolaidou; Maria Lambropoulou; G. Alexiadis; J. Manavis; N. Papadopoulos

Primary gastric Hodgkins lymphoma is a rarely encountered lesion. Most cases are observed in the course of systemic disease. Other cases have been reclassified in retrospective studies as non-Hodgkins lymphomas, after the employment of immunohistochemistry. Some Hodgkins lymphomas may masquerade non-Hodgkins lymphomas, and vice versa. Therefore, an accurate diagnosis is important, as treatment and outcome differ significantly for these entities. We report a case of primary Hodgkins lymphoma arising in the stomach of a 46-year-old male, and discuss the diagnostic approach as well as the differentials of Hodgkins disease in this anatomic site.


Clinical and Experimental Medicine | 2006

Imbalance of mononuclear cell infiltrates in the placental tissue from foetuses after spontaneous abortion versus therapeutic termination from 8th to 12th weeks of gestational age

Maria Lambropoulou; D. Tamiolakis; J. Venizelos; V. Liberis; George Galazios; Panagiotis Tsikouras; D. Karamanidis; G. Petrakis; T. Constantinidis; M. Menegaki; N. Papadopoulos

Placental macrophages (Hofbauer cells) are located close to trophoblastic cells and foetal capillaries, which make them perfect candidates for involvement in regulatory processes within the villous core. Their capacity of producing several cytokines and prostaglandin-synthesising enzymes, and expressing vascular endothelial growth factor, indicate a possible role in placental development and angiogenesis in order to support pregnancy. Common cells to Hofbauer macrophages sharing similar cell surface markers (HLA-A, -B, -C and leukocyte common antigen) have been reported in the stroma, decidua and amnion, indicating additional foetal protection. Yet this is not always the case. Most spontaneous abortions occur before 12 weeks’ gestation, and most are due to chromosomal errors in the conceptus. Relatively few truly spontaneous abortions take place between 12 and 20 weeks’ gestation. Thereafter, between 20 and 30 weeks, another type of premature spontaneous termination becomes prevalent, which is due to ascending infection. The numbers of cells expressing the various markers of the monocytemacrophage lineage change throughout pregnancy. In the present study, we investigated the immunohistochemical expression of mononuclear infiltrations in paraffin-embedded placentas, from foetuses after spontaneous abortion (8th, 10th and 12th weeks of gestational age), and those after therapeutic abortion at the same time, using a panel of monoclonal antibodies for the identification of leukocytes (CD45/LCA), B-lymphocytes (CD20/L-26), T lymphocytes (CD45RO/UCHL1), CD68 and CD14 cells. Immunologic factors in human reproductive failure are plausible mechanisms of infertility and spontaneous abortion. Approximately 25% of cases of premature ovarian failure appear to result from an autoimmune aetiology. Unfortunately, current therapeutic options for these women are limited to exogenous hormone or gamete substitution. Local inflammations at the sites of endometriosis implants are postulated to mediate the pain and reduced fecundability associated with this clinical syndrome. The recruitment of immune cells, particularly monocytes and T-cells, neovascularisation around foci of invading peritoneal lesions, and the possible development of antiendometrial autoantibodies support an immunologic basis of this disorder. To date, treatment of pain and infertility associated with endometriosis is primarily surgical, although immune-based adjuvants are theoretical possibilities for the future. Finally, although hypotheses supporting immunologic mechanisms of recurrent pregnancy loss have been popular over the past decade, most clinical investigations in this area do not provide compelling evidence for this position. Reputable specialists in reproductive medicine use experimental immunotherapies judiciously in selected cases of repetitive abortion. For example, the use of anticoagulation therapy can be beneficial in cases with documented antiphospholipid antibodies. At present, however, efficacious immunotherapy protocols for general application have not been established. Despite these caveats, continued strides in our understanding of human reproductive immunology should yield considerable future progress in this field. During the physiological changes that occur in the first and in the beginning of the second trimester of pregnancy, spiral arteries of the placental bed are converted into the uteroplacental arteries. The essence of this conversion consists of losing the muscular elements in the vessel walls, making them unable to respond to vasomotor influences. Cells that infiltrate the walls of spiral arteries and replace their normal elements are called migratory, non-villous or intermediate trophoblastic cells. Besides infiltrating and replacing the anatomic structures of spiral arteries, intermediate trophoblastic cells also penetrate into the lumina of these vessels forming endovascular plugs. These plugs are one of the reasons why early uteroplacental blood flow cannot be visualised, even with transvaginal ultrasound, during the first 12 weeks of gestation. In uncomplicated pregnancies, the endovascular trophoblast is bound to disappear by the end of the second trimester of pregnancy, but the literature on this topic is scarce. Here we describe the detection, isolation and characterisation of CD45RO-, L26- and CD68/CD14-positive cells from human early pregnancy deciduas. These cells were found in close vicinity to endometrial glands, with preference to the basal layer of the decidua. We conclude that (1) maternal cells, apparently CD45RO/UCHL1-positive cells, cross the maternofoetal barrier and participate in spontaneous (involuntary) abortions, and (2) a small proportion of maternal cells (approximately 30%), apparently CD68/CD14-positive cells, also cross the maternal-foetal barrier and cause growth delay and recurrent reproductive failure. Further investigation of involvement of the intercellular adhesion molecules 1 and 2, platelet endothelial cell adhesion molecule, vascular cell adhesion molecule and E-selectin in leukocyte accumulation will be needed to support the passage of maternal cells to the foetus. The results were statistically significant (P<0.0001, Student’s t-test).


Onkologie | 2004

Intrahepatic Extramedullary Hematopoietic Tumor Mimicking Metastatic Carcinoma from a Colonic Primary

D. Tamiolakis; J. Venizelos; P. Prassopoulos; Constantinos Simopoulos; Sophia Bolioti; M. Tsiapali; N. Papadopoulos

Background: Extramedullary hematopoiesis (EMH) is associated with a number of diseases in which the normal function of the bone marrow is disturbed. While organs with hemopoietic capacity like the liver and spleen are most commonly involved, EMH has also occasionally been found in other organs like the adrenal gland, lymph nodes, breast, thymus, small bowel and central nervous system. However, presentation of a myeloproliferative disorder, such as EMH in these organs is a rare event. Case Report: We report clinical and fine-needle aspiration (FNA) findings in a patient who presented with intrahepatic EMH which mimicked metastatic carcinoma from a colonic primary. Results: Ultrasound-guided FNA of the intrahepatic mass revealed megakaryocytes and myelocytes thus establishing the diagnosis of EMH. Conclusions: EMH is an unusual condition that can mimic other solid masses of the liver. Because radiologic findings are not specific, EMH should be considered in the differential diagnosis, especially in patients with a myeloproliferative disorder. FNA and subsequent cytopathological interpretation of the aspirates enables avoidance of unnecessary potentially hazardous surgery.


Clinical and Experimental Medicine | 2003

Prognostic significance of HLA-DR antigen in serous ovarian tumors

D. Tamiolakis; Kotini A; J. Venizelos; T. Jivannakis; P. Simopoulos; N. Papadopoulos

Abstract.The antigens encoded by the major histocompability complex (HLA-DR) are cell glycoproteins that play a fundamental role in the regulation of the immune response. The prognosis of ovarian cancer is dependent on the histological type and on the clinical stage at diagnosis. Our study reports the value of HLA-DR antigen as a prognostic marker of ovarian serous adenocarcinoma. We studied 31 cases of serous ovarian cystadenoma, 12 cases of serous ovarian borderline cystadenoma, and 39 cases of well-differentiated cystadenocarcinoma for HLA-DR monoclonal antigen. We also studied the T helper marker (CD4) in the tumor stroma of the relevant cases, given that it is now known that the dependence of immune responsiveness on the class II antigens reflects the central role of these molecules in presenting antigen to T helper cells. HLA-DR was expressed in 20 of 31 cystadenomas (64.5%), 4 of 12 borderline tumors (33.3%), and in 10 of 39 invasive carcinomas (25.6%). CD4 was expressed in 9 of 31 cystadenomas (29%), 5 of 12 borderline tumors (42%), and in 26 of 39 invasive carcinomas (67%). There was a statistically significant difference for the two examined antigens in cystadenomas (p<0.001) and invasive carcinomas (p<0.001), whereas there was no statistical difference in borderline tumors (p<0.5). The results showed decreased expression of HLA-DR and increased expression of CD4 as the lesion progressed to malignancy. The aberrant expression of HLA-DR by epithelial cells of cystadenomas, of borderline tumors, and of invasive adenocarcinomas agrees with the hypothesis of the adenoma/adenocarcinoma sequence. The immune attraction mechanism by low HLADR signaling seems to be of minor importance in the malignant and metastatic potential of serous ovarian tumors.


Clinical and Experimental Medicine | 2009

Differential expression of tenascin-C in the developing human lung: an immunohistochemical study

Maria Lambropoulou; V. Limberis; N. Koutlaki; M. Simopoulou; D. Ntanovasilis; G. P. Vandoros; P. Tatsidou; I. Kekou; I. Koutsikogianni; N. Papadopoulos

Much of the specification for the basic embryonic body plan is the result of a hierarchy of developmental decisions at different developmental times. The extracellular matrix (ECM) appears to be a very dynamic structure during embryogenesis. One of the mesenchymal ECM proteins, tenascin, is reported to be transiently expressed during embryonic tissue development, and is absent or much reduced in most fully developed organs. The respiratory system is an outgrowth of the ventral wall of the foregut, and the epithelium of the larynx, trachea, bronchi and alveoli is of endodermal origin. The cartilaginous and muscular components are of mesodermal origin. The aim of this study was to investigate the role of tenascin-C (TNC) in the developing human lung, during the pseudoglandular, canalicular and saccular stage of lung maturation. Formalin-fixed, paraffin-embedded tissue from the lungs of 30 embryos (10 corresponding to the 10th to the 16th gestational week (pseudoglandular stage), 10 to the 17th to the 23rd gestational week (canalicular stage), and 10 to the 24th to the 27th gestational week (saccular stage), were investigated by conventional histology and immunohistology for the expression levels of TNC. The changes observed in the distribution patterns suggest that during embryogenesis, the rate of tenascin synthesis changes significantly. During the pseudoglandular stage, the density of cells expressing TNC was higher in the condensing mesenchyme surrounding the epithelial glands than in the epithelial cells, whereas the inverse result was observed during the canalicular stage. During the saccular stage the pattern of immunoreactivity with TNC was lower than those of the pseudoglandular and canalicular stage, either in epithelial or mesenchymal cells, but it was highly expressed in the basement membranes. This restricted spatiotemporal distribution suggests that tenascin has a key role (1) in mesenchymal tissue remodeling during the pseudoglandular stage, a period that describes the development of the complete bronchial tree and (2) on the epithelial cell shape and function during the canalicular stage, a period that describes the formation of pneumocytes type I and pneumocytes type II. The later, will produce the surfactant, a phospholipid-rich fluid capable of lowering surface tension at the air–alveolar interface. During the saccular stage, tenascin was present mainly in the basement membranes surrounding the acinar and vascular structures, indicating a supporting and mechanical role.


Onkologie | 2007

Cytoplasmic expression of c-erb-B2 in endometrial carcinomas.

Maria Lambropoulou; Dimitrios Stefanou; G. Alexiadis; D. Tamiolakis; Grigorios Tripsianis; Ekaterini Chatzaki; Gerasimos P. Vandoros; Anastasia Kiziridou; Evropi Papadopoulou; N. Papadopoulos

The aim of this study was to investigate the expression of c-erb-B2 in endometrial cancer with attention to both membranous and cytoplasmic staining, and to elucidate the significance of cytoplasmic signaling. Materials and Methods: c-erb-B2 reactivity was assessed by immunohistochemistry in 110 patients using a polyclonal antibody, and evaluated semiquantitatively according to the percentage of cells demonstrating membranous or diffuse cytoplasmic staining. Correlation was made with tumor stage, grade, myometrial invasion, histologic type, and disease outcome. Results: c-erb-B2 overexpression, indicated by membranous and cytoplasmic staining of at least 10% of the tumor cells, was found in 47 (42.7%) cases. Cytoplasmic expression of c-erb-B2 was observed more frequently than membranous (69.1 vs. 5.5%). Synchronous cytoplasmic and membranous signaling was noticed in 7.9% of cases. Interestingly, patients with cytoplasmic c-erb-B2-positive tumors had a significantly shorter survival (p = 0.047). Conclusions: These results indicate that c-erb-B2 is a specific marker of endometrial cancer. It is also an independent prognostic indicator of poor outcome. Cytoplasmic staining is as important as membranous staining, and is also a specific finding.


Leukemia & Lymphoma | 2004

Neutrophil-rich Anaplastic Large Cell Lymphoma (NR-ALCL) Mimicking Lymphadenitis: A Study by Fine-Needle Aspiration Biopsy

Tamiolakis D; G Georgiou; Panos Prassopoulos; Constantinos Simopoulos; J. Venizelos; N. Papadopoulos

A 45-year-old man presented to his practitioner with a 25day history of a painful tender nodule, measuring up to 2.5 cm in greatest dimension, in the right inguinal region. He had occasional complaints of pain down the anterior and lateral aspects of his right leg. No other palpable masses, skin lesions, or hepatosplenomegaly was identified. He was given a broad-spectrum antibiotic therapy, but the tenderness of the nodule did not resolve. Fifteen days later, the patient reported increased fatigue, but no fever, or recent weight loss. The patient was admitted for further analysis. Amongst the others, the laboratory tests for isolation of Chlamydia trachomatis (Frei test, complement-fixing antibodies, and microimmunofluorescence test for Chlamydia), were negative. Imaging studies did not show pelvic or elsewhere lymphadenopathy. A FNA biopsy on the inguinal nodule, using standard techniques with a 25-gauge needle, was performed. Airdried smears were stained with hemacolor and ethanolfixed smears were stained with Papanicolaou stain. The remaining fluid was centrifuged and cytospin preparations were made. A paraffin-embedded cell block was also prepared. The cytospin preparations and the direct smears were highly cellular consisting of small mature to large pleomorphic lymphoid cells intimately admixed with large numbers of neutrophils, representing up to 75% of all cells in some microscopic fields. Findings were suggestive of lymphadenitis, due to the intense presence of neutrophils. The cell block preparations showed an effacement of the architecture of the lymph node, with areas of suppurative necrosis surrounded by a cellular rim consisting of large-sized atypical lymphoid cells (Fig. 1). Higher magnification showed many of the atypical cells to have nuclei with a vesicular chromatin pattern and one or more prominent nucleoli. The surrounding cytoplasm was sometimes vacuolated. Numerous mitotic figures were identified. Classic Reed – Sternberg cells were scanty or absent. Immunocytochemical analysis performed on the cell block preparations revealed a CD30 and AKLpositive ALCL, T-cell type. Nuclear and cytoplasmic ALK-1 expression was seen in all tumor cells (Fig. 2), while CD30 showed a strong membranous staining with a paranuclear dot (Fig. 3). The atypical cells stained with antibodies for CD4/Leu-3a, CD43/Leu-22 (Bectin-Dickinson, San Jose, CA, USA), CD45/LCA, CD45RO/ UCHL-1, CD30/Ber-H2, and ALK protein/ALK-1 (Dako). Additional stains for CD3, CD15, CD20/L26, EMA/E29, kappa and Lambda polyclonal light chains (Dako) were negative. Most of the tumor cells showed nuclear p53 (Dako) staining and a high proliferative rate, confirmed by MIB-1/Ki67 staining of greater than 85%. The negative staining results with antibodies for S-100, Melan A/Klon A103, HMB-45/melanosome, cytokeratin coctail, myeloperoxidase and CD34 (Dako) effectively ruled out epithelial metastatic carcinoma, melanoma and granulocytic sarcoma respectively. Neutrophils were stained with CD15 but, as already stated, there was no staining of tumor cells with this antibody. The in situ hybridization for EBV, which was performed using a


Folia Histochemica Et Cytobiologica | 2012

Increased apoptotic activity on inflammatory human placentas in spontaneous abortions during the first and second trimester of gestation: a histochemical and immunohistochemical study

Theodora-Eleftheria Deftereou; Maria Lambropoulou; Ekaterini Chatzaki; Maria Koffa; Petros Ypsilantis; Olga Pagonopoulou; Iordana Grammatikopoulou; Elias Papadopoulos; Alexandros Papalambros; Emmanouil Kontomanolis; N. Papadopoulos

The aim of this study was to investigate the role of apoptotic markers on inflammatory human placentas from spontaneous abortions during the first and second trimester of gestation and compare them to those without inflammation. Paraffin-embedded specimens from 76 placentas were investigated by conventional histology and immunohistochemistry using monoclonal antibodies against M30, Caspase 3, Caspase 8 and Caspase 9, as well as the terminal deoxynucleotidyl tranferase-mediated deoxyuridine triphosphate nick end labeling method. A higher prevalence of expression of apoptotic markers (94.4%) was observed in placentas associated with chorioamnionitis in comparison with those without inflammation. Our observations confirm that apoptosis is strikingly prevalent in placentas diagnosed with histologic chorioamnionitis, while the inflammation induces cell death.

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Maria Lambropoulou

Democritus University of Thrace

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G. Alexiadis

Democritus University of Thrace

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Tamiolakis D

Democritus University of Thrace

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D. Tamiolakis

Democritus University of Thrace

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Kotini A

Democritus University of Thrace

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J. Venizelos

Democritus University of Thrace

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Constantinos Simopoulos

Democritus University of Thrace

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S. Nikolaidou

Democritus University of Thrace

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C. Simopoulos

Democritus University of Thrace

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Ioannis Venizelos

Democritus University of Thrace

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