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Ioannis Venizelos

Publications and source records attributed to Ioannis Venizelos.

15 recordsLinked to original sources
PubMed2006

Necrotic vasculitis in a patient with abdominal fibromatosis and Guillain-Barré syndrome.

The case of a 65-year-old woman presenting with Guillain-Barré syndrome is herein reported. Tomographic investigation revealed abdominal and retroperitoneal fibromatosis. During her hospitalization, renal involvement ensued, and subsequent renal biopsy demonstrated findings of crescentic pauci-immune glomerulonephritis negative for ANCA antibodies and with characteristics indicative of necrotic angiitis. The simultaneous existence of the three diseases in the same patient as well as the relation between necrotic vasculitis and G-B syndrome is speculated, and the relevant literature is reviewed.

Aged↗
PubMed2005

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

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/microL). 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.

Adult↗
PubMed2005

Aggressive angiomyxoma of the vulva extending into the pelvis: report of two cases.

Aggressive angiomyxoma is a rare soft-tissue neoplasm found mainly in the female pelvis. Approximately 130 cases have been reported in the literature to date. In most cases treatment consists of surgical resection, but local recurrence rates remain high (36-72%). Therefore, long-term follow up is necessary and magnetic resonance imaging seems to be the preferred method for detecting recurrence. We report our experience of a primary and a recurrent aggressive angiomyxoma.

Adult↗
PubMed2005

CD30 (Ki-1) molecule expression in human embryonal epithelial cells of the basal layer of the developing epidermis and epidermal buds and its potential significance for embryogenesis.

OBJECTIVE: CD30 antigen has long been considered to be restricted to tumour cells of Hodgkin's disease, of anaplastic large cell lymphoma and T and B activated lymphocytes. Expression of CD30 antigen has been reported in the decidual stroma, cultivated macrophages, lipoblasts, myoepithelial cells, reactive and neoplastic vascular lesions, mesotheliomas, embryonal carcinoma and seminoma cells. The fact that the CD30 molecule can mediate signals for cell proliferation or apoptosis prompted us to perform a systematic investigation of CD30 antigen expression in embryonal tissues during the proliferation and differentiation stages. We first targeted foetal human intestinal cryptae cells with positive results. The epidermis is a dynamic epithelium that is constantly renewed throughout life. Its turnover is estimated at about 7 days in mice and about 60 days in humans. This rapid replacement demands, as with other epithelial tissues, that an adult has stem cells capable of supplying differentiated cells throughout life. The most basic and widely accepted criteria for these stem cells are that they have a high capacity for self-renewal and the ability to generate daughter cells that undergo terminal differentiation. Not all of the proliferative cells in the basal layer are stem cells and we were intrigued to find out if stem or other cells in the basal layer can express the CD30 antigen. MATERIALS AND METHODS: We investigated the immunohistochemical expression of CD30 antigen in 15 paraffin-embedded tissue samples representing epidermis and epidermal buds from foetuses after spontaneous abortion in 8th, 10th, and 12th week of gestation, respectively, using the monoclonal antibody Ki-1. RESULTS: The results showed that the epithelial cells of the epidermis in the developing skin express the CD30 antigen and CD30 expression in these epithelial cells is higher in cases of hormonal administration than in normal gestation. A similar positive reaction was observed in the epidermal buds associated with the development of the skin appendages.

Epidermis↗
PubMed2004

Acute large bowel pseudo-obstruction due to multiple myeloma.

Involvement of the gastrointestinal (GI) tract by multiple myeloma (MM) is extremely rare. The small intestine and stomach are the most frequent sites of spread. We report 1 case of a 61-year-old woman who presented with clinical and radiographic features of an acute large bowel pseudo-obstruction. An abdominal computerized tomography (CT) showed a large tumor of the rectum. On morphological and immunohistochemical examination the tumor fulfilled the criteria of MM. The patient received combined chemotherapy and radiotherapy which led to the disappearance of the tumor. A review of the literature revealed that this is the first reported case of MM presented as acute large bowel pseudo-obstruction due to a rectal myeloma tumor.

Colonic Pseudo-Obstruction↗
PubMed2004

Does neoplastic cholecystokinin expression reflect the embryonal pattern of the protein? A study in human pancreas.

AIM: To determine the immunoreactivity of cholecystokinin (CCK) during the development of the human fetal pancreas and pancreatic adenocarcinoma, given that, CCK positive cells were demonstrated either in its embryonic anlage or in pancreatic cancer. In order to obtain possible parallels in the expression pattern of neoplastic cells in adults (well--moderately--poorly differentiated), we investigated the pattern of CCK expression in the pancreatic tissue during the various stages of development and compared these with the proliferation of tissue assessed by proliferating cell nuclear antigen (PCNA) immunohistochemistry. EXPERIMENTAL DESIGN: Tissue sections from 15 pancreatic fetal specimens, and equal number of ductal adenocarcinoma specimens, were assessed using immunohistochemical methods for CCK. RESULTS: The density of positive cells in the primitive exocrine ductal walls and outgrowing buds was significantly higher than the relevant density in the neoplastic pancreatic tissue of mixed (ductal-endocrine) and pure ductal type (p1=0.004, p2 < 0.0005, p3 < 0.0005 and p4=0.023 respectively). The above values were estimated from 20th to 22nd weeks of gestation. There was no significant difference in the density of positive cells in the islet cell epithelium from 25-30 weeks, and the neoplastic tissue of mixed (p5=0.10) and pure ductal type (p6=0.15). CONCLUSIONS: The immunostaining for CCK identifies a sub-group of pancreatic ductal adenocarcinomas with a neuroendocrine component (initially considered as pure ductal tumors), and mixed ductal-endocrine tumors. This pattern of expression in neoplasms recapitulates the normal pattern during the embryonal development of the organ, and may be important for the development of new therapeutic approaches with eventual clinical utility.

Adenocarcinoma↗
PubMed2004

Altered intrahepatic hematopoiesis in neonates from women with pregnancy induced hypertension/pre-eclampsia.

AIM: To detect whether preeclampsia influences neonatal intrahepatic hematopoiesis, given that an activation of fetal neutrophils and monocytes during the course of this disorder occurs. EXPERIMENTAL DESIGN: We examined liver samples from 10 neonates of hypertensive/preeclamptic women at 27 to 28 weeks of gestation delivered by a cessarian section. All neonates were placed in incubators but they all died within 24 hours due to immaturity. The control group comprised 10 fetuses of the same gestational age, after voluntary abortion due to a neural defect. Specific antibodies against CD34, glycophorin C, hemoglobins A and F, myeloperoxidase, CD61, CD68, terminal desoxynucleotidyl transferase and the pax-5/B-cell specific activator protein, were used in each sample. RESULTS: Neonates from hypertensive/preeclamptic women, in comparison with controls, showed: a statistically significant reduction of erythropoiesis by 25% (p=0.015); a statistically significant increase of granulopoiesis (p=0.019); a statistically significant increase in the expression of CD68 positive cells of the monocytic lineage (p=0.017); a statistically significant increase in the expression of CD34 progenitor/stem positive cells (p=0.021). No statistically significant differences were observed in both examined groups, concerning megakaryopoiesis and B lymphopoiesis. CONCLUSIONS: Preeclampsia of pregnancy has an impact on neonatal intrahepatic hematopoiesis by increasing granulopoiesis, reducing erythropoiesis and triggering endothelial and stem cell activation. We suggest that these findings reflect a state of persistent inflammation and a loss of red blood cell production possibly contributing to the neonatal morbidity related to this disorder.

Female↗
PubMed2004

Human decidual cells activity in women with spontaneous abortions of probable CMV aetiology during the first trimester of gestation. An immunohistochemical study with CMV-associated antigen.

AIM: To determine the expression of CMV-associated antigen in the human decidual endometrial stromal cells in spontaneous abortions with no evidence of maternal relapse during the first trimester of gestation. EXPERIMENTAL DESIGN: We examined 15 placentas resulting from intrauterine fetal death after spontaneous abortion during the 8th, 10th, and 12th week of gestation respectively, and in which CMV reactivation was ruled out from serological evaluation of the pregnant women at admission, versus equal controls after voluntary abortion following well-documented maternal viral recurrence. In addition, a panel of monoclonal antibodies for the identification of leukocytes (CD45/LCA), B-lymphocytes (CD20/L-26), and T-lymphocytes (CD45RO/UCHL1), was performed. All women received hormonal medication to support gestation, in the cases of spontaneous abortions. RESULTS: Immunohistochemical examination using a specific antibody against cytomegalovirus showed large multinucleated infected cells with intranuclear inclusions, located primarily in the decidual stroma within a lymphoplasmacytic infiltrate in the cases of spontaneous abortions. No evidence of infection was observed in the chorionic villi. In the cases of voluntary abortions same findings were observed in the relevant areas, and a strong evidence of infection was observed in the chorionic villi. CONCLUSION: This study demonstrates 1) that the decidual endometrial stromal cells can express the CMV-associated antigen prior to serological manifestation of the viral replication, 2) the expression of the antigen is higher in cases of hormonal administration to support gestation. In these cases a mild mononuclear infiltrate of UCHL1 (T marker) positive cells, accompanies the CMV-associated antigen positive cells.

Abortion, Spontaneous↗
PubMed2004

Gains and losses of HLA class II (DR) and CD4 in atypical hyperplasia, carcinoma in situ and infiltrating ductal carcinoma of the breast.

AIM: Breast cancer is a frequent cause of death among women with gynaecologic malignancies despite the introduction of combination chemotherapy. There is therefore a need for new therapeutic strategies for patients with breast cancer, such as cellular immunotherapy. In this immunohistochemical study we analyzed the epithelial expression of major histocompatibility complex (MHC) class II (HLA-DR) on atypical and malignant primary mammary epithelial cells, as well as the magnitude of the stromal T lymphocytes (T4 subset) at the tumor site. EXPERIMENTAL DESIGN: The study was carried out retrospectively in tumor tissue from 82 patients with mammary lesions (31 cases of atypical ductal hyperplasia -ADH-, 12 cases of ductal carcinoma in situ -DCIS- and 39 cases of infiltrating ductal carcinoma not otherwise specified -IDC-NOS). Medullary carcinomas were not included in our investigation. Material used had been formalin fixed and paraffin embedded. RESULTS: HLA class II (DR) was expressed in 20 of 31 ADHs (64.5%), in 4 of 12 DCISs (33.3%), and in 10 of 39 IDC-NOSs (25.6%). CD4 was expressed in 9 of 31 ADHs (29%), in 5 of 12 DCISs (42%), and in 26 of 39 IDC-NOSs (67%). CONCLUSIONS: The results showed decreased epithelial expression of HLA class II (DR) and increased stromal expression of CD4, as the lesion progressed to malignancy. Gradual loss of epithelial HLA class II expression might be a manifestation of cellular differentiation from the atypical form versus the malignant one, signaling simultaneously a selective effect on the response capacity of the immune system.

Adult↗
PubMed2003

Pancreatic-polypeptide in the human pancreas: expression and quantitative variation during development and in ductal adenocarcinoma.

AIM: To determine the immunoreactivity of pancreatic-polypeptide (PP) during the development of the human fetal pancreas and ductal pancreatic adenocarcinoma, given that, PP positive cells were demonstrated either into its embryonic anlage or into pancreatic cancer. METHODS: Tissue sections from 15 pancreatic fetal specimens, and equal number of ductal adenocarcinoma specimens, were assessed. RESULTS: The density of positive cells in the primitive exocrine ductal epithelium and endocrine epithelium was significantly higher than the relevant density in the neoplastic pancreatic tissue of mixed (ductal - endocrine) and pure ductal type (p1 = 0.001, p2 < 0.0005, p3 = 0.046 and p4 < 0.0005 respectively). The above values were estimated during the 10th to 12th week. There was no significant difference in the density of positive cells in the mantle zone of the islets from the 13th to the 24th week, and the neoplastic tissue of mixed (p5 = 0.11) and pure ductal type (p6 = 0.23). CONCLUSION: The immunostaining for PP identifies a subgroup of pancreatic ductal adenocarcinomas with a neuroendocrine component, initially considered as pure ductal tumors, and mixed ductal and neuroendocrine tumors. This pattern of expression in neoplasms recapitulates the normal pattern during the embryonal development of the organ, raising the question of therapeutic efficacy of PP and analogues as potential adjuvant treatment of pancreatic cancer.

Adenocarcinoma↗
PubMed2003

Prevalence of CD8/CD4 ratio in the fetal thymic parenchyme in Down's syndrome.

AIM: The maturation of most T-lymphocyte precursors takes place within the meshwork of thymic epithelial cells. Different steps of this process can be defined by immunologic phenotyping. The prothymocytes are positive for the terminal deoxynucleotidyl transferase (TdT) and give rise to cortical thymocytes, which express CD1, CD2, CD3, CD5, and both CD4 and CD8. These CD4 and CD8 double-positive cortical thymocytes differentiate into two lineages: CD4+ or CD8+ lymphocytes of the thymic medulla, by the tenth week of gestation. Our study points towards the determination of the CD8 cytotoxic/suppressor capacity of the fetal thymus in Down's syndrome. EXPERIMENTAL DESIGN: A quantitative comparison of T-lymphocytes (CD3, CD4, and CD8) in the thymic parenchyme in embryos after voluntary abortion during 2nd trimester of gestation and embryos with Down's syndrome, respectively, was performed. RESULTS: Our results showed: 1) A statistically significant depletion in the total number of T-cells (CD3 positive) in the cases of embryos with Down's syndrome over those after voluntary abortion, during the second trimester of gestation (p<0.0001, t-test). 2) A significant difference in the CD8/CD4 ratio in the cases of embryos with Down's syndrome, during the second trimester of gestation which was numerically stronger with the progress of fetal development (20th week: p<0.025; 24th week: p<0.01, chi-square). CONCLUSIONS: The occurrence of increased CD8/CD4 ratio in the cases with Down's syndrome, in the second trimester of gestation, underlines the cytotoxic/suppressor property of the thymus in the affected fetuses.

CD4-CD8 Ratio↗
PubMed2002

Low-grade chondrosarcomas: a difficult target for radionuclide imaging. Case report and review of the literature.

Bone scan with Tc-99m (technetium) diphosphonate is sensitive, but non-specific for musculoskeletal tumors. Tl-201 (thallium), Tc-99m-sestamibi, Tc-99m-tetrofosmin, and F-18-fluorodeoxyglucose (F-18-FDG) can visualize tumors more specifically and are therefore useful in orthopedic oncology. However, cartilaginous tumors are characterized by histological and biological features, which potentially impair specific radionuclide imaging. A case of a patient with a low-grade primary chondrosarcoma of the femur and a false negative Tl-201 scan is presented. Tc-99m-based tumor-localizing compounds (sestamibi, tetrofosmin), as well as metabolic and receptor-imaging radiopharmaceuticals have also been reported to fail in low-grade chondrosarcomas imaging. Low cellularity, mitochondrial specialization and the presence of an efflux membrane pump may contribute to poor imaging. A negative Tl-201 or Tc-99m-sestamibi scan should be interpreted with caution, when the possibility of a chondrosarcoma is not negligible.

Aged↗