Biomedical subjects

G Delides

Publications and source records attributed to G Delides.

At least 19 recordsLinked to original sources

PubMed2002

Changing pattern of cytokeratin 7 and 20 expression from normal epithelium to intestinal metaplasia of the gastric mucosa and gastroesophageal junction.

It is currently unclear whether intestinal metaplasia at the esophagogastric junction and in the distal esophagus represent a continuum of the same underlying disease process, i.e., gastroesophageal reflux, or constitute different entities with a different pathogenesis. Biopsies below the Z line might show specialized epithelium in some patients and the question is whether this is another form of short segment Barrett's esophagus or whether it is related to a generalized atrophic process of the stomach. Data from recent studies regarding the expression of cytokeratin CK7 and CK20 in intestinal metaplasia (IM) found at the gastroesophageal junction are conflicting. Prompted by these data we undertook the present study: a) to evaluate the expression of CK7 and CK20 in IM of the gastric cardia and to compare the findings with those in patients with Barrett's esophagus and IM of the gastric corpus and antrum mucosa; and b) to evaluate the immunophenotype of non-intestinalized cardiac mucosa and to compare it with that of normal gastric epithelium. We studied the expression of CK7 and CK20 on biopsy specimens from patients with long-segment Barrett's esophagus (n=17) and surgical resection and biopsy specimens of gastric cardia (n=15), corpus (n=14) and antrum (n=22) from patients with histological evidence of IM. Eighty-four biopsy specimens from 42 patients (antrum n=15, corpus n=20, cardia n=7) without evidence of IM were studied as a control group. We observed an immunophenotype characterised by diffuse moderate to strong CK7 staining on the surface and crypt epithelium combined with strong CK20 staining on the surface and superficial part of the crypts in 94.1% (16/17) of the cases with long-segment Barrett's esophagus, but in none of the 36 cases with IM in distal stomach (antrum and corpus). IM in the gastric cardia expressed the immunophenotype seen in IM of the gastric mucosa in 93.3% (14/15) of the cases. On the other hand, normal cardiac epithelium expressed patchy strong CK7 staining on the surface epithelium and on both, superficial and deep parts of the pits combined with patchy strong CK20 staining on the surface epithelium and superficial pits, a feature permitting distinction of the normal cardiac epithelium from those of the normal gastric antrum and corpus epithelium. We conclude that the expression of cytokeratins 7 and 20 can be used to distinguish the origin of IM of the gastroesophageal junction. The CK7/20 immunophenotype of IM in the gastric cardia closely resembles that of the IM in the gastric antrum and corpus and is different from IM in long-segment Barrett's esophagus. In contrast, the CK7/20 immunophenotype of the cardiac epithelium is different from that of the gastric antrum and corpus mucosa, suggesting that cardiac epithelium might not be a native normal gastric epithelium but one that is acquired as a consequence of longstanding inflammation. Changing pattern of CK7 and CK20 expression from normal to intestinalized epithelium suggests that IM arising from cardiac epithelium might have distinctive features.

Barrett Esophagus↗

PubMed2001

Pleuropulmonary blastoma: an aggressive intrathoracic neoplasm of childhood.

A case of a 4-year-old girl with pleuropulmonary blastoma is reported. Surgical resection of the tumor was performed and histologic examination revealed pleuropulmonary blastoma with rhabdomyosarcomatous differentiation. Postoperative chemotherapy was administered and 3 weeks after initiation of treatment protocol a second site of lesion in the retroperitoneum was revealed with extension to the mediastinum, which shared similar mesenchymal neoplastic characteristics to the previously diagnosed primary lesion. The girl died 4 1/2 months after initial evidence of disease because of brain metastasis, indicating a very aggressive neoplasm unresponsive to treatment.

Brain Neoplasms↗

PubMed2000

Immediate free flap mandibular reconstruction in osteosarcoma of the mandible in childhood.

Mandibular osteogenic sarcoma (OS) is a very rare entity in childhood. Adequate surgical rejection with a wide margin of normal tissue is the mainstay of treatment of this site, while the role of adjuvant chemotherapy remains uncertain. A case is presented of a 15 1/2-year-old male with a huge OS of the mandible. The boy underwent surgical resection of the mandible with immediate fibula free flap reconstruction and is alive and free of disease 6 1/2 years following unitial diagnosis. This case suggests that immediate bone reconstitution with vascularized grafts have good functional and morphological results for osteosarcoma of the lower jaw.

Adolescent↗

PubMed2000

Image analysis of mesothelioma. I. differentiation of mesothelioma from adenocarcinoma of the lung.

OBJECTIVE: To explore the usefulness of nuclear micromorphometric analysis for the differentiation between epithelial mesothelioma and metastatic adenocarcinoma in the chest wall. STUDY DESIGN: High-resolution images of 2,100 nuclei from 27 cases of epithelial mesothelioma and 15 cases of adenocarcinoma of the lung were recorded. Stepwise discriminant analysis and a nonparametric classifier were applied to derive estimates for a case diagnosis correct classification rate. RESULTS: Nuclei from epithelial mesothelioma and adenocarcinoma of the lung showed statistically significantly different properties, but there was a region of overlap in feature space such that approximately 15-20% of cases could not be correctly classified. The lesion signatures derived from the mesothelioma cases with discriminant function scores that might result in case misclassification and the cases of adenocarcinoma of the lung spanned a similar range of degree of nuclear abnormality. However, the distribution of nuclear abnormality values for the mesothelioma cases has a mode at 0.87 SD from normal, whereas the distribution seen in lung adenocarcinoma cases had a mode at about 3.7 SD. CONCLUSION: Cases of epithelial mesothelioma and adenocarcinoma of the lung have nuclei with a wide range of deviation from normal in the spatial and statistical distribution of their nuclear chromatin. For approximately 80% of cases, correct case classification can be provided by nuclear micromorphometric analysis. Cases of epithelial mesothelioma with highly abnormal nuclei overlap in feature space with nuclei from adenocarcinoma of the lung. However, it is possible that characterization by a lesion signature may allow correct assignment for those cases.

Adenocarcinoma↗

PubMed2000

Image analysis of mesothelioma. II. Discrimination of mesothelioma from metastatic serous ovarian adenocarcinoma.

OBJECTIVE: To examine the utility of karyometric measurements in the differentiation of mesothelioma from metastatic serous ovarian adenocarcinoma. STUDY DESIGN: High-resolution images of 1,631 nuclei from 32 cases of mesothelioma and 742 nuclei from 15 cases of ovarian adenocarcinoma were recorded. A stepwise discriminant analysis and nonparametric classifier were applied. RESULTS: Nuclei from these two diagnostic categories appear very similar and occupy feature space with significant overlap. A nonparametric classification procedure provided acceptable correct classification. CONCLUSION: For certain regions in feature space, cases could be unequivocally classified.

Cell Nucleus↗

PubMed1998

Congenital capillary hemangioma and its therapeutic approach in infants: a case report.

Hemangiomas, common congenital lesions in infants and children, are thought to arise when islands of angioblastic tissue fail to connect with the developing vascular system. They are not usually life-threatening. A case of congenital capillary hemangioma in an infant, which was surgically excised, is reported, and therapeutic approaches are discussed.

Blood Vessels↗

PubMed1997

Expression of p53, mdm2, p21/waf1 and bcl-2 proteins in thymomas.

We have investigated the immunohistochemical expression of p53, mdm2, p21/waf1 and bcl-2 proteins in 31 thymic epithelial tumours comprising five medullary thymomas (MDT), four mixed thymomas (MT), 12 cortical thymomas (CT), eight predominately cortical thymomas (PCT) and two well-differentiated thymic carcinomas (WDTC). We have found p53, mdm2, p21 and bcl-2 protein expression in 25/31, 8/31, 5/31 and 10/31 thymic epithelial tumours, respectively. Coexpression of p53 and mdm2 proteins was found in eight cases (three CT, four PCT and one WDTC). Five of them were also p21 positive and three p21 negative. Discordant p53+/mdm2-/p21- protein expression was found in 19 cases (three MDT, three MT, nine CT, three PCT and one WDTC). Mdm2 and p21 proteins were not expressed in the absence of p53 protein. Coexpression of bcl-2 and p53 proteins was found in seven cases (three MDT, three MT and one WDTC). Eighteen cases were p53+/bcl-2- (10 CT, seven PCT and one WDTC) and three cases (two MDT and one MT) were bcl-2+/p53-. Our findings indicate that in thymomas, p53 expression is more frequently associated with cortical histotypes while bcl-2 expression is strongly associated with medullary and mixed histotypes. In addition, there is an inverse correlation between p53 and bcl-2 protein expression in thymomas. Coexpression of p53/mdm2/p21 proteins may reflect thymomas with wild-type (wt), p53 gene since mdm2 and p21 proteins are inducible by wt p53 gene. However, in view of previous findings that p53 mutation is an early event in thymomas, the possibility of p53 gene mutation with p53-independent mdm2 and p21 expression should be considered in these cases. Discordant p53+/mdm2-/p21- protein expression may represent thymomas with p53 gene mutations unable to activate expression of mdm2 and p21 proteins.

Cyclin-Dependent Kinase Inhibitor p21↗

PubMed1997

Cervical cytology in adolescence.

The prevalence of cervical intraepithelial neoplasia in young women is increasing worldwide. Frequency of the abnormal Papanicolau smears was examined in sexually active young females aged 13 to 19 years. The smears were reported as within normal limits or with benign cellular changes due to inflammation in 96.2% of cases. The cytological changes were related in 2.5% of cases of HPV infection, in 1.0% of cases to CIN I and in 0.3% of cases to CIN II. These results show a frequency of 3.8% of abnormal smears.

Adolescent↗

PubMed1996

Morphologic differences between latent membrane protein-1 (LMP-1)-positive and negative tumour cells in Epstein-Barr virus (EBV)-related childhood Hodgkin's disease. A morphometric study.

The values of five cellular morphometric parameters (longest and shortest cytoplasmic axis, cellular circumference, area and roundness coefficient) were compared between 20 Latent Membrane Protein 1 (LMP-1)-positive and an equal number of LMP-1-negative Reed-Sternberg and Hodgkin (HRS) cells for each of 13 cases of Hodgkin's disease (HD) occurring in children (aged 3-15 years); the presence of Epstein-Barr virus (EBV) encoded EBER mRNAs had previously been detected in all cases using RNA in situ hybridisation (RISH), while the presence of LMP-1 was immunohistochemically detected using the alkaline phosphatase-antialkaline phosphatase (APAAP) method. The longest and shortest axis, circumference and area were larger in LMP-1-positive than in LMP-1 negative HRS cells, while the roundness coefficient of LMP-positive HRS cells was smaller than that of LMP-1 negative cells. All differences were statistically highly significant when univariate (paired comparisons) t-test were used. Multivariate analysis (Hotelling's T2 test) showed all differences (except the roundness coefficient) to be significant both at the 5% and 1% level of significance. These results provide a numerical basis for the alteration brought by the expression of LMP-1 in the cellular skeleton of tumour (HRS) cells in EBV-related childhood HD cases.

Adolescent↗

PubMed1996

p53 protein expression in non-Hodgkin's lymphoma. Comparative study with the wild type p53 induced proteins mdm2 and p21/waf1.

Aims-To investigate the pattern of expression of p53 protein and two wild type p53 induced proteins (mdm2 and p21/waf1) as an indirect way of assessing p53 gene status in non-Hodgkin's lymphoma.Methods-Formalin fixed, paraffin wax embedded tissue from 87 cases of nodal non-Hodgkin's lymphoma, comprising 52 high grade and 35 low grade tumours, was stained by immunohistochemistry for p53, mdm2 and p21/waf1 proteins.Results-p53, mdm2 and waf1/p21 proteins were expressed in 36/52, 21/52 and 31/52 high grade and 3/35, 21/35 and 3/35 low grade non-Hodgkin's lymphomas, respectively. Parallel p53/mdm2 protein expression was found in 23 cases (21 high grade and two low grade). These 23 cases were also positive for p21/waf1 protein expression. Discordant p53 positive/mdm2 negative protein expression was found in 16 cases (15 high grade and one low grade). Eleven (10 high grade and one low grade) of these 16 cases were p21/waf1 positive and the remaining five high grade non-Hodgkin's lymphomas were p21/waf1 negative. Mdm2 and p21/waf1 proteins were not expressed in the absence of p53 protein expression.Conclusions-p53, mdm2 and waf1/p21 protein expression is more frequently associated with aggressive histotypes of non-Hodgkin's lymphoma. Parallel expression of p53, mdm2 and p21 proteins may represent non-Hodgkin's lymphomas with a wild type p53 gene as mdm2 and p21 proteins can be induced by the wild type gene. In these cases p53 protein expression may result from stabilisation via complex formation with the mdm2 protein. This could be important in the pathogenesis of these cases as mdm2 may deregulate the p53 dependent growth suppressive pathway. Discordant p53 positive/mdm2 negative/p21 negative protein expression may represent non-Hodgkin's lymphoma with p53 gene mutations unable to activate expression of mdm2 and p21 proteins. Non-Hodgkin's lymphoma with p53 positive/mdm2 negative/p21 positive protein expression may have either wild type p53 with deregulated mdm2 gene expression or mutated p53 gene with p53 independent p21 expression.

Journal Article↗

PubMed1995

Expression of bcl-2 and p53 proteins in nasopharyngeal carcinoma. Absence of correlation with the presence of EBV encoded EBER1-2 transcripts and latent membrane protein-1.

Aims-To investigate the immunohistochemical expression of bcl-2 and p53 proteins in nasopharyngeal carcinomas in relation to the expression of the Epstein-Barr virus (EBV) encoded EBER messenger RNAs (mRNAs) and latent membrane protein-1 (LMP-1).Methods-Formalin fixed, paraffin wax embedded tissue from 44 nasopharyngeal carcinomas (NPCs) was stained by immunohistochemistry for p53, bcl-2 and LMP-1 proteins and by RNA in situ hybridisation for EBER mRNAs.Results-The tumours were divided histologically into 13 cases of keratinising squamous cell NPC (KNPC), 15 cases of non-keratinising squamous cell NPC (NKNPC) and 16 cases of undifferentiated NPC (UNPC). Bcl-2 expression was observed in five of 15 NKNPC cases and in six of 16 UNPC cases; p53 expression was observed in one of 13 KNPC, two of 15 NKNPC and four of 16 UNPC cases. EBER 1-2 transcripts were detected in five of 15 NKNPC and nine of 16 UNPC cases, while LMP-1 expression was observed in one of 16 UNPC cases. All 13 KNPCs were EBV and bcl-2 negative. No correlation was found between the presence of EBER 1-2 transcripts and the detection of bcl-2 or p53 proteins, or both, in NPC cells.Conclusions-The expression of bcl-2 and p53 proteins may be associated with the level of the tumour cell differentiation in NPC. In addition, in view of the important role of the bcl-2 protein in the inhibition of apoptosis, the expression of bcl-2 protein may contribute to tumour cell survival in a proportion of NPCs. Furthermore, in the light of previous findings that the p53 gene in most UNPCs is in the wild-type configuration, mechanisms other than mutation may be responsible for stabilisation of the p53 protein in UNPCs.

Journal Article↗

PubMed1995

MDM-2 protein expression in nasopharyngeal carcinomas. Comparative study with p53 protein expression.

Aims-To investigate the immunohistochemical expression of MDM-2 protein in comparison with that of p53 protein in nasopharyngeal carcinomas.Methods-Formalin fixed, paraffin wax embedded tissue from 59 cases of nasopharyngeal carcinoma was stained by immunohistochemistry for MDM-2 and p53 proteins.Results-The tumours were divided histologically into seven cases of keratinising nasopharyngeal carcinoma (KNPC), 14 cases of non-keratinising nasopharyngeal carcinoma (NKNPC), and 38 cases of undifferentiated nasopharyngeal carcinoma (UNPC). MDM-2 nuclear expression was observed in 0/7 KNPC, 1/14 NKNPC, and 11/38 UNPC. p53 nuclear expression was observed in 1/7 KNPC, 2/14 NKNPC, and 15/38 UNPC. Parallel MDM-2 and p53 expression was found in 12 cases (11 UNPC and one NKNPC). Discordant MDM-2-/p53 + expression was found in six cases (four UNPC, one NKNPC, and one KNPC), and absence of expression of both proteins in the remaining 41 cases.Conclusions-Expression of MDM-2 and p53 proteins may be associated with the level of tumour cell differentiation in nasopharyngeal carcinoma. Simultaneous expression of MDM-2/p53 in a proportion of UNPC suggests that MDM-2 protein may be responsible for stabilisation of p53 protein in these cases, in view of the previous demonstration of the p53 gene in germ line configuration. This could be important in the pathogenesis of these cases, since MDM-2 may deregulate the p53 dependent growth suppressive pathway. Discordant MDM-2-/p53 + expression in a few cases of nasopharyngeal carcinoma may reflect stabilisation of p53 protein by other proteins, or p53 mutations unable to activate MDM-2.

Journal Article↗

PubMed1995

Beta 2-microglobulin and HLA-DR expression in relation to the presence of Epstein-Barr virus in nasopharyngeal carcinomas.

We have investigated the immunohistochemical expression of beta 2-microglobulin and HLA-DR proteins in nasopharyngeal carcinoma (NPC) in relation to the expression of the Epstein-Barr virus (EBV)-encoded EBER 1-2 mRNAs and LMP-1 protein. beta 2-Microglobulin is expressed in association with MHC-I molecules on most nucleated cells and HLA-DR belongs to the MHC-II molecules which are expressed mostly on antigen-presenting cells. Formalin-fixed paraffin-embedded tissue from 37 NPC cases was stained with immunohistochemistry for beta 2-microglobulin, HLA-DR and LMP-1 proteins and by RNA in situ hybridization for EBER 1-2 mRNAs. beta 2-Microglobulin-positive staining was found in neoplastic cells in all cases. In 19/37 NPC cases the positive staining was found in most neoplastic cells. In the remaining 18 NPC cases more than 25% of the neoplastic cells showed significantly reduced or negative staining in comparison to the normal epithelium and infiltrating small lymphocytes. HLA-DR-positive staining was found in 27/37 NPC cases. EBER 1-2 transcripts were deteced in neoplastic cells in 13/37 NPC cases. LMP-1 expression in tumour cells was found in 4/13 EBER1-2-positive cases. No correlation was found between the presence of EBER1-2 transcripts or LMP-1 protein and the beta 2-microglobulin-reduced expression in NPC. Thus, EBV does not seem to use downregulation of MHC-I to avoid the T cell cytotoxic immune response in NPC. HLA-DR expression was observed in all 13 EBV-positive cases of NPC, suggesting that EBV may participate in the induction of HLA-DR expression in a proportion of NPC.

Adult↗

PubMed1995

Supporting telemicroscopy and laboratory medicine activities. The Greek "TELE.INFO.MED.LAB" project.

In this paper the authors present the basic results of the study for the "TELE.INFO.MED.LAB" project. This study is based on the local experience of the Metaxas Cancer Institute case and on international references. The possibilities rendered by current developments in telemedicine and particularly in telepathology accelerate and facilitate the communication of crucial medical data and creation of "second level" medical services overcoming the geographical particularities of the country. The availability of data transmission (signals, images, texts, etc.) enables the creation of a "uniform market" for various services. This system must take into account the financial realities, geographical aspects transportation problems and technological developments. Organization of this system, the choices of technical standards and the realization of a complete pilot project are described. For this system we also describe the functional and technical aspects, as well as software and hardware components for the different types of units.

Computer Communication Networks↗

PubMed1994

Frequent detection of Epstein-Barr virus (EBV), EBER transcripts and latent membrane protein-1 (LMP-1) in tumor cells in Hodgkin's disease arising in childhood.

Paraffin sections from 22 cases of Hodgkin's disease (HD) and 30 cases of non-Hodgkin's lymphomas (NHL) occurring in childhood (3-15 years old) were examined for the presence of Epstein-Barr Virus (EBV) encoded EBER mRNAS and Latent Membrane Protein-1 (LMP-1) using RNA in situ hybridization (RISH) and immunohistochemistry, respectively. In 12/22 (54%) cases of HD the EBER transcripts were detected in most Reed-Sternberg and Hodgkin (HRS) cells as well as in some scattered smaller lymphoid cells. In all these cases the LMP-1 protein was detected exclusively in HRS cells. Three additional cases of HD were found to be EBER RISH positive only in a few scattered small lymphoid cells, the LMP-1 staining being negative in these cases. The EBER and LMP-1 positivity in HRS cells were present in 0/1 of lymphocyte predominant, 4/10 (40%) of nodular sclerosis and 8/11 (72%) of mixed cellularity of HD. No EBER RISH signal was found in tumor cells of the 30 cases of NHL. In four of them only a few scattered small lymphoid cells were EBER RISH positive. LMP-1 reactivity was not detected in any NHL. These results provide evidence for an association between EBV and a sizeable proportion of childhood Hodgkin's disease and show that this association is more frequent in mixed cellularity subtype. Furthermore, the detection of the LMP-1 protein in HRS cells in view of the LMP-1 transforming potential, suggests that EBV may be involved in the pathogenesis of a substantial proportion of cases of HD occurring in childhood.

Adolescent↗

PubMed1992

Proliferating cell nuclear antigen (PCNA) expression in childhood lymphomas.

Paraffin sections from 21 cases of Hodgkin's disease (HD) and 28 cases (26 high-grade and 2 low-grade) of non-Hodgkin's lymphomas (NHL) occurring in childhood were examined for the presence of proliferating cell nuclear antigen using an anti-PCNA antibody. All cases of HD and NHL showed PCNA reactivity. In HD 50.9% (mean value) of Hodgkin and Reed-Sternberg (HRS) cells were PCNA positive and judged to be proliferating. PCNA reactivity was also found in a varying number of cells of the background population in HD (mean value = 11.7%). In NHL 61.2% (mean value) of cells were PCNA positive. In the 26 high grade tumours 63.6% (mean value) of cells were PCNA positive while only 32% (mean value) of cells were PCNA positive in the 2 low-grade tumours. Our results show that the proliferation rate of tumour cells in high-grade NHL is higher than those of tumour cells in low-grade NHL and HRS cells in HD. Moreover, we found a considerable variation of proliferation rate among individual cases of HD (range 31%-68%) of NHL (range 31%-78%). This suggests that PCNA assessment can help in the individual approach of the proliferation rate of each tumour, and, in conjunction with other parameters of the cell proliferation, could be useful for the understanding of the biological behavior of childhood lymphomas.

Adolescent↗

PubMed1992

Expression of the Epstein-Barr virus encoded latent membrane protein in tumor cells of Hodgkin's disease occurring in childhood.

Paraffin sections from 21 cases of Hodgkin's disease (HD), 28 cases of non-Hodgkin's lymphomas (NHL) and 34 cases of non-specific reactive lymphadenitides occurring in childhood were examined for the presence of the Epstein-Barr Virus (EBV)-encoded Latent Membrane Protein (LMP) using a double layer immunohistochemical method. LMP was detected in 12/21 (57%) cases of HD but not in NHL or reactive lymph nodes. LMP reactivity was restricted to Reed-Sternberg and Hodgkin's (HRS) cells in 4 of 9 (45%) cases of nodular sclerosis (NS), 6 of 9 (66%) cases of mixed cellularity (MC) and 2 of 2 (100%) cases of lymphocyte depletion (LD) while it was undetectable in the single case of lymphocyte predominance (LD) subtype. These results provide further evidence for an association between EBV and Hodgkin's disease, and they show that LMP expression occurs more frequently in the clinically more aggressive subtypes of HD. Furthermore, in view of the in vitro transforming potential of the LMP protein, the exclusive immunolocalization of LMP in HRS cells, suggests that EBV may be involved in the pathogenesis of a proportion of cases of HD.

Adolescent↗

PubMed1989

Variation of vascular density within and between tumors of the uterine cervix and its predictive value for radiotherapy.

Vascular density in different regions of a number of uterine cervix carcinomas was determined by morphometric analysis of stained histologic sections. Variance analysis indicated a larger inter- than intra-tumoral inhomogeneity of the vasculature, suggesting a certain individual vascularization pattern in these tumors. As indicated by a retrospective study of archival biopsies, this pattern has a predictive value in regard to the efficacy of radiotherapy.

Carcinoma, Squamous Cell↗