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N Papadopoulos

Publications and source records attributed to N Papadopoulos.

At least 19 recordsLinked to original sources
PubMed2006

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.

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).

Abortion, Induced↗
PubMed2006

Loss of chromosome 1 in myxopapillary ependymoma suggests a region out of chromosome 22 as critical for tumour biology: a FISH analysis of four cases on touch imprint smears.

OBJECTIVE: Ependymomas are glial tumours. They constitute approximately 5-10% of intracranial tumours and are tumours which can recur. Predictive factors of outcome in ependymomas are not well established. Karyotypic studies are relatively scarce and loss of chromosome 22 has been described to correlate with recurrence. We are unaware of any reports involving chromosome 1 aberrations in the malignant progression of ependymomas. METHODS: Cytogenetic analysis of four myxopapillary ependymomas was performed using double target fluorescent in situ hybridization (FISH), focusing on chromosomes 1 and 22. RESULTS: One patient's tumour had recurred. FISH was performed on 500 nuclei/tumours. All four cases showed a loss of chromosome 22q while only one showed an additional loss of chromosome 1p, and this was the one that recurred. CONCLUSIONS: We support the presence of a tumour suppressor gene on 1p associated with relapse in myxopapillary ependymomas and suggest that status of chromosome 1p by FISH may indicate a high-risk group of patients harbouring this tumour. More studies of this type are needed towards this direction as our results refer to a minimal number of individuals analysed.

Adult↗
PubMed2006

Pharmacologic and anti-IgE treatment of allergic rhinitis ARIA update (in collaboration with GA2LEN).

The pharmacologic treatment of allergic rhinitis proposed by ARIA is an evidence-based and step-wise approach based on the classification of the symptoms. The ARIA workshop, held in December 1999, published a report in 2001 and new information has subsequently been published. The initial ARIA document lacked some important information on several issues. This document updates the ARIA sections on the pharmacologic and anti-IgE treatments of allergic rhinitis. Literature published between January 2000 and December 2004 has been included. Only a few studies assessing nasal and non-nasal symptoms are presented as these will be discussed in a separate document.

Animals↗
PubMed2006

Tissue remodelling in upper airways: where is the link with lower airway remodelling?

Tissue remodelling reported in upper airways include epithelial hyperplasia, increased matrix deposition in the nasal or paranasal lining, matrix degradation and accumulation of plasma proteins. Genetic influences, foetal exposures and early life events may contribute to structural changes such as subepithelial fibrosis from an early age. Other structural alterations are related to duration of the disease and long-term uncontrolled inflammation. Structural changes may increase alteration of the protective functions of the upper airways namely by affecting mucociliary clearance and conditioning of inspired air. The sequences of tissue changes during wound repair of upper airway mucosa after surgery are illustrative of the complexicity of tissue modelling and remodelling and could be considered as an important source of information for a better understanding of the complex relationship between inflammatory reaction, of the subsequent tissue damages and fibroblast metabolism of upper airways.

Animals↗
PubMed2006

Angiogenic effect of intramuscular administration of basic fibroblast growth factor in atrophied muscles: an experimental study in the rat.

BACKGROUND: Although angiogenic therapy using recombinant growth factors holds much hope for the treatment of ischaemic diseases, there are still many unanswered questions, including its effectiveness on atrophic muscles. OBJECTIVE: To evaluate the angiogenic effects of intramuscularly administered basic fibroblast growth factor (b-FGF) on normal gastrocnemius muscles of rats and atrophic gastrocnemius muscles after tenotomy. METHODS: Forty rats were divided into groups as follows: group A, controls; group B, injected with 1 microg b-FGF; group C, tenotomy performed on the right gastrocnemius muscle; group D, tenotomy and 1 microg b-FGF. Mouse anti-rat CD31 antibody was used to evaluate the number of blood vessels present in histological preparations. RESULTS: There was a significant (p<0.01) decrease in the number of blood vessels compared with the controls in the atrophic muscles of group C. This was similar to the decrease in muscle weight in this group. However, there was a significant (p<0.01) increase in the number of blood vessels compared with the controls in groups B and D. Similarly, there was a significant (p<0.01) increase in the number of blood vessels in group D compared with the atrophic muscles in group C. CONCLUSION: Intramuscular administration of b-FGF increases angiogenesis in both normal and atrophic rat gastrocnemius muscles at the injection area.

Angiogenesis Inducing Agents↗
PubMed2006

Human embryonal tissues of all three germ layers can express the CD30 antigen. An immunohistochemical study of 30 fetuses coming after therapeutic abortions from week 8th to week 16th of gestation.

Originally, expression of the CD30 antigen was shown to be typical of the tumor cells of Hodgkin disease and of anaplastic large cell lymphomas. In reactive lymphoid tissue, CD30 is expressed only in a small population of activated lymphoid blasts. Since then, several reports have been published describing CD30 expression in non lymphoid tissues and neoplasms, such as embryonal carcinomas, seminomas, cultivated macrophages, histiocytic neoplastic cells, deciduals cells, and mesothelioma cells. In order to gain insight into the functions of CD30, given that it can mediate signals for cell proliferation and apoptosis, we studied the distribution of the antigen in different fetal archival paraffin-embedded tissues from week 8th to 16th of gestation. We investigated the immunohistochemical expression of CD30 in 30 paraffin-embedded tissue samples representing all three germ layers, using the monoclonal antibody Ber-H2 CD30 is expressed early in human fetal development (8th-10th week) in a wide variety of tissues, with the exception of the skin and thymus in which it is expressed later on. This is consistent with the observation that these organs are not fully differentiated before 10th and 13th week, respectively. No expression was observed in the cardiovascular and respiratory systems. The finding of CD30 expression in the terminal period of organogenesis, period, which is highly hormone related, implies that the antigen has an important role in cell development, maturation, and pathway to terminal differentiation in almost all fetal tissues and structures.

Abortion, Therapeutic↗
PubMed2006

Branchial cysts. A report of 4 cases.

OBJECTIVE: Cysts presented in the lateral aspect of the neck are relatively uncommon anomalies. Many theories have been proposed to explain the aetiology of these cysts, grouped in two main categories: the congenital and the cervical lymph nodes cystic transformation hypotheses. SETTINGS: In this paper we present 4 patient-cases documented in the department of Maxillofacial Surgery, and try to trace the profile of these lesions and investigate their origin. RESULTS: All lesions were well circumscribed by Computed Tomography, and prior to surgery they were assessed by means of fine needle aspiration cytology. Neutrophils, debris and mature squamous epithelial cells including degenerate forms, were the key-features in the cytological diagnosis. Histologic examination of the excised surgical specimen established the diagnosis in all cases. CONCLUSIONS: Our findings, compatible with the congenital theory lead us to the conclusion that the branchial cysts are the result of imperfect obliteration of the branchial clefts, arches, and pouches.

Adult↗
PubMed2005

Contribution of combined colposcopy and cytology in cervical pathology.

AIM: The regular Papanicolaou (Pap) smear is the cornerstone of women's preventive healthcare. The introduction of the regular Pap smear as a screening tool for cervical cancer has markedly decreased the number of deaths from cervical cancer. During the past decade, however, the rate of death from cervical cancer has remained relatively static. This screening method is known to have a high percentage of false negative results. To improve the detection of cervical lesions using the Pap smear in screening, a number of adjunct procedures have been developed. The purpose of this study is to evaluate the utility of a magnified chemoluminescent screening examination (Colposcopy) combined with the Pap smear in detecting cervical abnormalities. METHODS: We investigated a cohort of 58 subjects who have been forwarded for colposcopic evaluation due to referral cytology suggestive of persistent inflammatory process not otherwise specified, and cervical intraepithelial or invasive neoplasia, in Chania Colposcopic clinic. RESULTS: The higher the lesion detected by cytology, the more severe the corresponding colposcopic impression viewed. CONCLUSION: The data presented here are in harmony with previous reports and share our experience in a Regional Community Hospital Colposcopy Clinic. An integrated cytology-colposcopy program facilitates the assessment and identification of women harboring cervical pathological conditions.

Adult↗
PubMed2005

Ber-H2 (CD30) immunohistochemical staining of human fetal tissues.

OBJECTIVE: CD30 antigen has long been considered to be restricted to the tumour cells of Hodgkin's disease and of anaplastic large cell lymphoma as well as to T and B activated lymphocytes. It is now apparent that the range of normal and neoplastic cells, which may express CD30 antigen, is much wider than was at first thought. In order to gain insight into the physiological function of CD30 antigen, we studied the distribution of its expression in the tissues of fetuses from week 8th to week 16th. MATERIALS AND METHODS: We investigated the immunohistochemical expression of CD30 antigen in paraffin-embedded tissue samples representing all systems from 30 fetuses after therapeutic abortion at 8th to 10th and 12th to 16th week of gestation, respectively, using the monoclonal antibody Ber-H2. RESULTS: Our results demonstrated that CD30 is expressed early in human fetal development (8th to 10th week of gestation) in several fetal tissues derived from all three germ layers (gastrointestinal tract, special glands of the postpharyngeal foregut, urinary, musculoskeletal, reproductive, nervous, endocrine systems), with the exception of the skin and hematolymphoid system (thymus), in which the antigen is expressed later on (10th week onwards). Expression of CD30 was restricted to the hematolymphoid system in the 12-16 weeks of gestation. No expression of the marker was observed in the respiratory and cardiovascular systems during the entire period examined. CONCLUSIONS: CD30 antigen is of importance in cell development, and proliferation. It is also pathway-related to terminal differentiation in many fetal tissues and organs.

Antibodies, Monoclonal↗
PubMed2005

Distribution of somatostatin in pancreatic ductal adenocarcinoma remodels the normal pattern of the protein during foetal pancreatic development: an immunohistochemical analysis.

AIM: To determine the immunoreactivity of somatostatin during the development of the human fetal pancreas and pancreatic ductal adenocarcinoma, given that, somatostatin-positive cells were demonstrated either into its embryonic anlage or into pancreatic cancer. METHODS: Tissue sections from 15 pancreatic fetal specimens, and an 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 different from the relevant density in the neoplastic pancreatic tissue of mixed (ductal-endocrine) and pure ductal type (P1=0.021 P2=0.001, P3<0.0001, P4=0.003 respectively). The above values were estimated from the 8th to 10th 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=0.16) and pure ductal type (P6=0.65). CONCLUSION: The immunostaining for somatostatin 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 somatostatin and analogues as monotherapy in pancreatic cancer management.

Adenocarcinoma↗
PubMed2005

NCL-CD30 staining of epithelial cells in the basal germinative layer of the epidermis and epithelial buds during foetal skin development.

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 proliferation and differentiation stages. We first targeted the foetal human intestinal cryptae cells with positive results. The epidermis is a dynamic epithelium that is constantly renewed throughout life. The basal layer, attached to the basement membrane, contains the dividing cells of the skin and as cells move up from this layer they undergo differentiation, ending in the formation of a terminally differentiated anucleate cell called squame. It is intriguing to find out if cells in the basal layer can express the CD30 antigen. 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 the 8th, 10th and 12th weeks of gestation, respectively, using the monoclonal antibody NCL-CD30. A Northern blotting analysis was additionally performed. The results showed that: (1) the epithelial cells of the epidermis in the developing skin express the CD30 antigen; (2) CD30 expression in these epithelial cells is higher in cases of hormonal administration than in normal gestation; (3) a similar positive reaction involved the epidermal buds associated with the development of the skin appendages. Northern blots of tissue sections using a CD30 cDNA probe detected mRNAs of the same molecular mass and variety similarly to those in the positive control cell line HUT 102.

Antibodies, Monoclonal↗
PubMed2005

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

Primary gastric Hodgkin's 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-Hodgkin's lymphomas, after the employment of immunohistochemistry. Some Hodgkin's lymphomas may masquerade non-Hodgkin's 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 Hodgkin's lymphoma arising in the stomach of a 46-year-old male, and discuss the diagnostic approach as well as the differentials of Hodgkin's disease in this anatomic site.

Hodgkin Disease↗
PubMed2005

VEGF trap as a novel antiangiogenic treatment currently in clinical trials for cancer and eye diseases, and VelociGene- based discovery of the next generation of angiogenesis targets.

The concept that tumors can be controlled by directly targeting their vascular supply has finally come of age, because clinical trials using a humanized monoclonal antibody that blocks VEGF have demonstrated exciting efficacy in cancer patients, as well as in vascular eye diseases that can lead to blindness. However, data suggest that these current regimens may not provide complete VEGF inhibition and, thus, that the maximum therapeutic potential of VEGF blockade has not yet been achieved. We describe the status of a very potent and high-affinity VEGF blocker, termed the VEGF Trap, that may provide the opportunity to maximize the potential of VEGF blockade in cancer as well as in vascular eye diseases. We also describe use of the VEGF Trap as a research tool, when coupled to high-throughput mouse genetics approaches such as VelociGene that can be exploited in strategies to discover and validate the next generation of angiogenesis targets.

Angiogenesis Inhibitors↗
PubMed2005

Local immune response in serous papillary carcinoma of the endometrium.

OBJECTIVE: Serous papillary carcinomas of the endometrium are aggressive tumors that tend to permeate, in a very extensive fashion, to uterine and adnexal lymphatic and vascular channels at an early stage in their evolution, and are associated with a particularly gloomy prognosis. It is generally thought that even tumors apparently limited to the endometrium or confined to an endometrial polyp have a poor outcome. Our study points towards the value of HLA-DR antigen in the outcome of serous papillary endometrial cancer. Our aim was to assess the HLA-DR expression in inactive, endometrial intraepithelial carcinoma (EIC), and invasive serous carcinoma curretage specimens from the endometrial cavity, suggesting a role in immune response to keep tumor proliferation in check. STUDY DESIGN: Thirty-one cases of inactive endometrium, twelve cases of EIC, and thirty-nine cases of serous papillary invasive carcinoma curettings were evaluated for the detection of HLA-DR monoclonal antigen. T helper (TH) marker (CD4) in the tumor stroma of the relevant cases was also studied, 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 TH cells. RESULTS: HLA-DR was expressed in 20 of 31 inactive endometrium (64.5%), 4 of 12 in EIC (33.3%), and in 10 of 39 serous papillary invasive carcinomas (25.6%). CD4 was expressed in 9 of 31 inactive endometrium (29%), 5 of 12 in EIC (42%), and in 26 of 39 serous papillary invasive carcinomas (67%). CONCLUSIONS: 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 inactive endometrium, of EIC and of serous papillary invasive carcinomas agrees with the hypothesis of the inactive endometrium - carcinoma in situ sequence as the usual route for the development of serous papillary invasive carcinoma. The immune attract mechanism by low HLA-DR signaling seems to be of minor importance in the malignant and metastatic potential of the serous papillary endometrial tumours.

Aged↗
PubMed2005

Oxidants in asthma and in chronic obstructive pulmonary disease (COPD).

Experimental and clinical evidences suggest that oxidants play a role in the pathogenesis of respiratory disorders characterised by chronic airway inflammation such as asthma and chronic obstructive pulmonary disease (COPD). The respiratory system is chronically exposed to environmental pollutants, including oxidants. Exogenous sources of oxidants are particularly relevant to the pathogenesis of COPD, being cigarette smoke an extremely rich source of oxidants. In addition, the inflammatory cells recruited to the airways of patients with asthma and COPD, have an exceptional capacity to produce oxidants. Many decades of research have produced a significant amount of data indicating pro-oxidative molecular mechanisms putatively relevant in the pathogenesis of the oxidative stress which characterises these diseases, both locally and systemically. As a consequence, a drug therapy able to restore the redox imbalance in asthma and COPD would probably exert clinical and functional benefits. Indeed, currently available therapies for asthma and COPD can exert an inhibitory effect on oxidant production in the airways. However, it is unknown whether the efficacy of the treatment is somehow linked to the pharmacological modulation of the oxidant/antioxidant balance. So far, it appears that the potential role of antioxidant compounds in the treatment of asthma and COPD has not been fully explored.

Antioxidants↗