68 results on '"Panopoulou E"'
Search Results
2. SEARCHING HPV GENOME FOR METHYLATION SITES INVOLVED IN MOLECULAR PROGRESSION TO CERVICAL PRECANCER: EP456
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Kottaridi, C, Pergialiotis, V, Leventakou, D, Pouliakis, A, Chrelias, G, Patsouri, E, Zacharatou, A, Panopoulou, E, Damaskou, V, Sioulas, V, Chrelias, C, Kalantaridou, S, and Panayiotides, I
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- 2019
- Full Text
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3. Out-of-sample equity premium prediction: a complete subset quantile regression approach
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Meligkotsidou, L. Panopoulou, E. Vrontos, I.D. Vrontos, S.D.
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This paper extends the complete subset linear regression framework to a quantile regression setting. We employ complete subset combinations of quantile forecasts in order to construct robust and accurate equity premium predictions. We show that our approach delivers statistically and economically significant out-of-sample forecasts relative to both the historical average benchmark, the complete subset mean regression approach and the single-variable quantile forecast combination approach. Our recursive algorithm that selects, in real time, the best complete subset for each predictive regression quantile succeeds in identifying the best subset in a time- and quantile-varying manner. © 2019 Informa UK Limited, trading as Taylor & Francis Group.
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- 2021
4. EP456 Searching HPV genome for methylation sites involved in molecular progression to cervical precancer
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Kottaridi, C, primary, Pergialiotis, V, additional, Leventakou, D, additional, Pouliakis, A, additional, Chrelias, G, additional, Patsouri, E, additional, Zacharatou, A, additional, Panopoulou, E, additional, Damaskou, V, additional, Sioulas, V, additional, Chrelias, C, additional, Kalantaridou, S, additional, and Panayiotides, I, additional
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- 2019
- Full Text
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5. Growth potential and carcass characteristics of native Machaeras, Damascus, and Machaeras x Damascus male kids
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Koumas, A., primary, Mavrogenis, A.P., additional, Papachristoforou, C., additional, Panopoulou, E., additional, and Rogdakis, E., additional
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- 2005
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6. SEARCHING HPV GENOME FOR METHYLATION SITES INVOLVED IN MOLECULAR PROGRESSION TO CERVICAL PRECANCER
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Kottaridi, C. Pergialiotis, V. Leventakou, D. Pouliakis, A. and Chrelias, G. Patsouri, E. Zacharatou, A. Panopoulou, E. and Damaskou, V. Sioulas, V. Chrelias, C. Kalantaridou, S. and Panayiotides, I.
- Published
- 2019
7. Searching HPV genome for methylation sites involved in molecular progression to cervical precancer
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Leventakou, D. Pouliakis, A. Pergialiotis, V. Chrelias, G. Patsouri, E. Zacharatou, A. Panopoulou, E. Damaskou, V. Sioulas, V. Chrelias, C. Kalantaridou, S. Panayiotides, I.G. Kottaridi, C.
- Abstract
Background: Human Papilloma Virus has been considered as the main cause for cervical cancer. In this study we investigated epigenetic changes and especially methylation of specific sites of HPV genome. The main goal was to correlate methylation status with histological grade as well as to determine its accuracy in predicting the disease severity by establishing optimum methylation cutoffs. Methods: In total, sections from 145 cases genotyped as HPV16 were obtained from formalin-fixed, paraffin-embedded tissue of cervical biopsies, conization or hysterectomy specimens. Highly accurate pyrosequencing of bisulfite converted DNA, was used to quantify the methylation percentages of UTR promoter, enhancer and 5’ UTR, E6 CpGs 494, 502, 506 and E7 CpGs 765, 780, 790. The samples were separated in different groupings based on the histological outcome. Statistical analysis was performed by SAS 9.4 for Windows and methylation cutoffs were identified by MATLAB programming language. Results: The most important methylation sites were at the enhancer and especially UTR 7535 and 7553 sites. Specifically for CIN3+ (i.e. HSIL or SCC) discrimination, a balanced sensitivity vs. specificity (68.1%, 66.2% respectively) with positive predictive value (PPV) and negative predictive value (NPV) (66.2%, 68.2% respectively) was achieved for UTR 7535 methylation of 6.1% cutoff with overall accuracy 67.1%, while for UTR 7553 a sensitivity 60.9%, specificity 69.0%, PPV=65.6%, NPV=64.5% and overall accuracy=65.0% at threshold 10.1% was observed. Conclusion: Viral HPV16 genome was found methylated in NF-1 binding sites of UTR in cases with high grade disease. Methylation percentages of E6 and E7 CpG sites were elevated at the cancer group. © The author(s).
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- 2019
8. Quantile forecast combinations in realised volatility prediction
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Meligkotsidou, L. Panopoulou, E. Vrontos, I.D. Vrontos, S.D.
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This paper tests whether it is possible to improve point, quantile, and density forecasts of realised volatility by conditioning on a set of predictive variables. We employ quantile autoregressive models augmented with macroeconomic and financial variables. Complete subset combinations of both linear and quantile forecasts enable us to efficiently summarise the information content in the candidate predictors. Our findings suggest that no single variable is able to provide more information for the evolution of the volatility distribution beyond that contained in its own past. The best performing variable is the return on the stock market followed by the inflation rate. Our complete subset approach achieves superior point, quantile, and density predictive performance relative to the univariate models and the autoregressive benchmark. © 2019, © 2019 Operational Research Society.
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- 2019
9. Backtesting VaR and ES under the magnifying glass
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Argyropoulos, C., Panopoulou, E., Argyropoulos, C., and Panopoulou, E.
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Backtesting provides the means of determining the accuracy of risk forecasts and the corresponding risk model. Given that the actual return generating process is unknown, the evaluation methods rely on various assumptions in order to quantify the models inefficiencies and proceed with the model evaluation. These method specific assumptions, in conjunction with the regulatory policies can introduce distortions in the evaluation process, which affect the reliability of the evaluation results. To investigate such effects from a practitioner's perspective, this paper reviews the major Value at Risk and Expected Shortfall forecast evaluation methods and evaluates their performance under a common simulation and financial application framework. Our findings suggest that focusing on specific individual hypothesis tests provides a more reliable alternative than the corresponding conditional coverage ones. In addition, selecting a two-year out-of-sample period provides a significantly better power to relevance ratio than the more relevant but powerless regulatory one-year specification.
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- 2019
10. Isolated and percutaneous liver perfusion for unresectable metastatic liver tumors: a systematic review.
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Bramis, K., primary, Bagias, G., additional, Panopoulou, E., additional, Petrou, A., additional, Alexakis, N., additional, Toutouzas, K., additional, Konstadoulakis, M., additional, and Zografos, G., additional
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- 2019
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11. BCL2L12 protein overexpression is associated with favorable outcome in diffuse large B-cell lymphoma patients in the rituximab era
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Papageorgiou, S.G. Kontos, C.K. Foukas, P.G. Panopoulou, E. Vasilatou, D. Rapti, S.-M. Gkontopoulos, K. Bazani, E. Panayiotides, I.G. Dimitriadis, G. Scorilas, A. Pappa, V.
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- 2016
12. A quantile regression approach to equity premium prediction
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Meligkotsidou, L. Panopoulou, E. Vrontos, I.D. Vrontos, S.D.
- Abstract
We propose a quantile regression approach to equity premium forecasting. Robust point forecasts are generated from a set of quantile forecasts using both fixed and time-varying weighting schemes, thereby exploiting the entire distributional information associated with each predictor. Further gains are achieved by incorporating the forecast combination methodology into our quantile regression setting. Our approach using a time-varying weighting scheme delivers statistically and economically significant out-of-sample forecasts relative to both the historical average benchmark and the combined predictive mean regression modeling approach. Copyright © 2014 John Wiley & Sons, Ltd.
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- 2014
13. Does the “hidden heat-sensitive polymorphism” in electrophoresis of crude extracts involve loci other than the structural locus examined? Experiments with D. subobscura
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Tsakas, S. C. and Diamantopoulou-Panopoulou, E.
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- 1980
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14. Breast ductal endoscopy: How many procedures qualify?
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Zagouri, F. Sergentanis, T.N. Giannakopoulou, G. Panopoulou, E. Chrysikos, D. Bletsa, G. Flessas, J. Filippakis, G. Papalabros, A. Bramis, K.J. Zografos, G.C.
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skin and connective tissue diseases - Abstract
Background. Breast ductal endoscopy is a relatively new diagnostic method with ever growing importance in the work-up of patients with bloody nipple discharge. The ability to perform ductal endoscopy is very important and useful for breast fellows. Learning curve in breast ductal endoscopy remains a terra incognita, since no systematic studies have addressed this topic. The purpose of this study is to determine the point (number of procedures during training) beyond which ductal endoscopy is successfully performed. Findings. Ten breast fellows received training in our Breast Unit. For the training process, an ex vivo model was adopted. Fellows were trained on 20 surgical specimens derived from modified radical mastectomy for breast cancer. The target of the education program was to acquire proficiency in performing ductoscopy. The achievement of four consecutively successful ductal endoscopies was determined as the point beyond which proficiency had been achieved. The number of procedures needed for the achievement of proficiency as defined above ranged between 9 and 17 procedures. The median value was 13 procedures; i.e. 50% of trainees had achieved proficiency at the 13th procedure or earlier. Conclusion. These pilot findings point to approximately 13 procedures as a point beyond which ductal endoscopy is successfully performed; studies on a larger number of fellows are nevertheless needed. Further research, focusing on the learning curves of different training models of ductal endoscopy, seems desirable. © 2009 Zografos et al; licensee BioMed Central Ltd.
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- 2009
15. Minimizing underestimation rate of microcalcifications excised via vacuum-assisted breast biopsy: A blind study
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Zografos, G.C. Zagouri, F. Sergentanis, T.N. Nonni, A. Koulocheri, D. Fotou, M. Panopoulou, E. Pararas, N. Fotiadis, C. Bramis, J.
- Abstract
Purpose: The main disadvantage of Vacuum Assisted Breast Biopsy (VABB) is the probability of underestimating atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS). This study evaluates a modified way of performing VABB. Methods: 266 women with microcalcifications graded BI-RADS 3&4 underwent VABB (11G) on the Fischer's table. 133 women were allocated to the "standard" protocol and 24 cores were obtained (1 offset-main target and one additional offset). 133 women were randomly allocated to the "extended" protocol and 96 cores were excised (one offset- main target and 7 peripheral offsets). A preoperative diagnosis was established, and the removed volume was calculated. When precursor or malignant lesions were diagnosed, open surgery was performed. A second pathologist, blind to the preoperative results and to the protocol made the postoperative diagnosis. The discrepancy between preoperative and postoperative diagnoses was evaluated. Results: When the standard protocol was applied, the underestimation rate for preoperative ADH, lobular neoplasia (LN), DCIS was 16.7%, 50% and 14.3% correspondingly. In the extended protocol, no underestimation was present in LN, ADH, but the underestimation rate for DCIS was 6.3%. In the extended protocol, no precursor/malignant tissue was left after VABB in all ADH cases, in 87.5% of LN cases, in 73.3% of DCIS, and in 50% of invasive carcinomas. The volume excised was 2.33 ± 0.60 cc and 6.14 ± 1.30 cc for the standard and the extended protocol, respectively. The rate of hematoma formation did not differ between the two protocols. Conclusions: This recently introduced, "extended" way of performing VABB in microcalcifications safely minimizes the underestimation rate, which may lead to a modified management of ADH lesions. © 2007 Springer Science+Business Media, LLC.
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- 2008
16. Erbin is a novel SARA-interacting protein on early endosomes that negatively regulates TGF-beta/Activin signaling
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Sflomos, G., Kostaras, E., Panopoulou, E., Pappas, N., Hyvonen, M., Fotsis, T., and Murphy, C.
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Febs Journal
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- 2008
17. Evaluation of pain experienced during breast ductal endoscopy
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Zografos, G.C. Zagouri, F. Sergentanis, T.N. Gounaris, A. Pararas, N. Oikonomou, V. Panopoulou, E. Fotiadis, C. Bramis, J.
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Purpose. Ductal endoscopy is valuable for the differential diagnosis of bloody nipple discharge; however, the pain associated with this procedure has not been evaluated. This study aims to assess the pain experienced by patients during ductal endoscopy. Methods. We studied a consecutive series of women who underwent ductal endoscopy, to investigate the cause of bloody nipple discharge. The procedure was performed using standard local anesthesia (lidocaine 1% 10 ml without epinephrine, involving nipple block and periaureolar administration). Patients were asked to score the level of pain with a visual analog scale, 1, 4, 7, 12, 17, 22, 27, and 32 min after the procedure, and describe their overall and maximum pain. Results. This series comprised 20 women aged from 27 to 68 years old. The overall pain (mean ± SE) score was equal to 5.8 ±0.3, and the maximum pain score was 8.3 ± 0.2. The peak of pain corresponded with when the dilator was inserted through the sphincter. The group in which the dilator was inserted after 4 min experienced more intense maximum and overall pain after 7, 12, 17 and 22 min. Conclusions. Pain is an important factor in ductal endoscopy, and peaks relatively early. A standard, baseline local lidocaine dose of greater than 10 ml may be necessary at the beginning of the procedure. Late insertion of the dilator seems to be an indicator of the force of the procedure. © 2008 Springer.
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- 2008
18. Vacuum-assisted breast biopsy: The value and limitations of cores with microcalcifications
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Zagouri, F. Sergentanis, T.N. Nonni, A. Koulocheri, D. Fotou, M. Panopoulou, E. Panou, M. Fotiadis, C. Bramis, J. Zografos, G.C.
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body regions ,skin and connective tissue diseases - Abstract
The aim of this study was to assess cores with microcalcifications (CM) and without microcalcifications (CWM) obtained from vacuum-assisted breast biopsy (VABB). The study included 12 atypical ductal hyperplasias (ADH), 37 ductal carcinomas in situ (DCIS), and seven invasive ductal carcinomas (IDC) diagnosed by VABB (11 G) on the Fischer's table. More than 24 cores were excised. For CM/CWM, a separate pathology report was given. Open surgery followed, and underestimation was calculated. The CM/CWM discrepancy was evaluated (superiority, identity, and inferiority). CWM failed to make the diagnosis in 8.3% and 35.1% of ADH and DCIS, respectively. In 28.6% of IDC, diagnosis was made through CWM. CM volume was 1.2±0.3 cm3 for the two IDCs missed by CM, 1.0±0.4 cm3 for the 40 cases of identical diagnoses, and 1.4±0.5 cm3 for the 14 cases of CM superiority (p=0.048, Kruskal-Wallis test). CWM volume was 6.3±1.8 cm3 for the two IDCs missed by CM, 2.6±1.8 cm3 for cases with identical diagnoses, and 3.4±1.6 cm3 for cases of CM superiority (p=0.018, Kruskal-Wallis test). The underestimation rate was 8.3% in ADH, and 10.8% in DCIS. CMs are superior in DCIS/ADH diagnosis. However, CWM may be valuable for the diagnosis of the invasive component. © 2007 Elsevier GmbH. All rights reserved.
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- 2007
19. Activin A suppresses neuroblastoma xenograft tumor growth via antimitotic and antiangiogenic mechanisms
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Panopoulou, E., Murphy, C., Rasmussen, H., Bagli, E., Rofstad, E. K., and Fotsis, T.
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Cyclin-Dependent Kinase Inhibitor p21 ,Angiogenesis Inhibitors/*therapeutic use ,Gene Expression Regulation, Neoplastic ,Inhibin-beta Subunits/*therapeutic use ,Mice, Nude ,Cell Movement/drug effects ,Smad2 Protein ,Tumor Suppressor Proteins/metabolism ,Cell Proliferation/drug effects ,Mice ,Vascular Endothelial Growth Factor Receptor-2/metabolism ,Tumor Cells, Cultured ,Animals ,Humans ,Neuroblastoma/metabolism/pathology/*prevention & control ,Smad3 Protein ,Trans-Activators/metabolism ,Cyclin-Dependent Kinase Inhibitor p15 ,Mice, Inbred BALB C ,DNA-Binding Proteins/metabolism ,Activin Receptors/metabolism ,Cell Cycle Proteins/metabolism ,Neovascularization, Pathologic ,Endothelial Cells/*drug effects/metabolism ,Xenograft Model Antitumor Assays ,Antineoplastic Agents/*therapeutic use ,Signal Transduction ,Activins/*therapeutic use ,Female ,Cyclin-Dependent Kinase Inhibitor p27 - Abstract
The tumor suppressor function of activin A, together with our findings that activin A is an inhibitor of angiogenesis, which is down-regulated by the N-MYC oncogene, prompted us to investigate in more detail its role in the malignant transformation process of neuroblastomas. Indeed, neuroblastoma cells with restored activin A expression exhibited a diminished proliferation rate and formed smaller xenograft tumors with reduced vascularity, whereas lung metastasis rate remained unchanged. In agreement with the decreased vascularity of the xenograft tumors, activin A inhibited several crucial angiogenic responses of cultured endothelial cells, such as proteolytic activity, migration, and proliferation. Endothelial cell proliferation, activin A, or its constitutively active activin receptor-like kinase 4 receptor (ALK4T206D), increased the expression of CDKN1A (p21), CDKN2B (p15), and CDKN1B (p27) CDK inhibitors and down-regulated the expression of vascular endothelial growth factor receptor-2, the receptor of a key angiogenic factor in cancer. The constitutively active forms of SMAD2 and SMAD3 were both capable of inhibiting endothelial cell proliferation, whereas the dominant-negative forms of SMAD3 and SMAD4 released the inhibitory effect of activin A on endothelial cell proliferation by only 20%. Thus, the effects of activin A on endothelial cell proliferation seem to be conveyed via the ALK4/SMAD2-SMAD3 pathways, however, non-SMAD cascades may also contribute. These results provide novel information regarding the role of activin A in the malignant transformation process of neuroblastomas and the molecular mechanisms involved in regulating angiogenesis thereof. Cancer Res
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- 2005
20. Model selection for estimating certainty equivalent discount rates
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Groom, B., Koundouri, P., Panopoulou, E., and Pantalidis, T.
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In a recent paper, Newell and Pizer (2003) (N&P) build upon Weitzman (1998, 2001)and show how uncertainty about future interest rates leads to ?certainty equivalent? forwardrates (CER) that decline with the time horizon. Such Declining Discount Rates(DDR?s) have important implications for the economic appraisal of the long-term policyarena (e.g. climate change) and inter-generational equity. This paper discusses the implicationsof N&P?s transition from the theory to practice in the determination of theschedule of discount rates for use in Cost Benefit Analysis (CBA). Using both UK &US data we make the following points concerning this transition: i) to the extent thatdifferent econometric models contain different assumptions concerning the distributionof stochastic elements, model selection in terms of specification and ?efficiency criteria?has important implications for operationalising a theory of DDR?s that depends uponuncertainty; ii) mispecification testing naturally leads to employing models that accountfor changes in the interest rate generating mechanism. Lastly, we provide an analysis ofthe policy implications of DDR?s in the context of climate change and nuclear build inthe UK and the US. In a recent paper, Newell and Pizer (2003) (N&P) build upon Weitzman (1998, 2001)and show how uncertainty about future interest rates leads to ?certainty equivalent? forwardrates (CER) that decline with the time horizon. Such Declining Discount Rates(DDR?s) have important implications for the economic appraisal of the long-term policyarena (e.g. climate change) and inter-generational equity. This paper discusses the implicationsof N&P?s transition from the theory to practice in the determination of theschedule of discount rates for use in Cost Benefit Analysis (CBA). Using both UK &US data we make the following points concerning this transition: i) to the extent thatdifferent econometric models contain different assumptions concerning the distributionof stochastic elements, model selection in terms of specification and ?efficiency criteria?has important implications for operationalising a theory of DDR?s that depends uponuncertainty; ii) mispecification testing naturally leads to employing models that accountfor changes in the interest rate generating mechanism. Lastly, we provide an analysis ofthe policy implications of DDR?s in the context of climate change and nuclear build inthe UK and the US.
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- 2004
21. Early endosomal regulation of Smad-dependent signaling in endothelial cells
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Panopoulou, E., Gillooly, D. J., Wrana, J. L., Zerial, M., Stenmark, H., Murphy, C., and Fotsis, T.
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Trans-Activators/*physiology ,Signal Transduction/*physiology ,Endothelium, Vascular/*physiology ,rab5 GTP-Binding Proteins/genetics/metabolism ,Smad Proteins ,Carrier Proteins/physiology ,Kinetics ,DNA-Binding Proteins/*physiology ,Receptors, Transforming Growth Factor beta/physiology ,Animals ,Cattle ,Phosphorylation ,Promoter Regions, Genetic ,Endosomes/*physiology ,Zinc Fingers/physiology ,Cells, Cultured - Abstract
Transforming growth factor beta (TGFbeta) receptors require SARA for phosphorylation of the downstream transducing Smad proteins. SARA, a FYVE finger protein, binds to membrane lipids suggesting that activated receptors may interact with downstream signaling molecules at discrete endocytic locations. In the present study, we reveal a critical role for the early endocytic compartment in regulating Smad-dependent signaling. Not only is SARA localized on early endosomes, but also its minimal FYVE finger sequence is sufficient for early endosomal targeting. Expression of a SARA mutant protein lacking the FYVE finger inhibits downstream activin A signaling in endothelial cells. Moreover, a dominant-negative mutant of Rab5, a crucial protein for early endosome dynamics, causes phosphorylation and nuclear translocation of Smads leading to constitutive (i.e. ligand independent) transcriptional activation of a Smad-dependent promoter in endothelial cells. As inhibition of endocytosis using the K44A negative mutant of dynamin and RN-tre did not lead to activation of Smad-dependent transcription, the effects of the dominant-negative Rab5 are likely to be a consequence of altered membrane trafficking of constitutively formed TGFbeta/activin type I/II receptor complexes at the level of early endosomes. The results suggest an important interconnection between early endosomal dynamics and TGFbeta/activin signal transduction pathways. J Biol Chem
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- 2002
22. The enigma of noninterest income convergence
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Antzoulatos, A. A., primary, Panopoulou, E., additional, and Tsoumas, C., additional
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- 2011
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23. Growth curves for body weight and carcass components, and carcass composition of the Karagouniko sheep, from birth to 720d of age
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Goliomytis, M., primary, Orfanos, S., additional, Panopoulou, E., additional, and Rogdakis, E., additional
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- 2006
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24. Growth curves for body weight and major component parts, feed consumption, and mortality of male broiler chickens raised to maturity
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Goliomytis, M, primary, Panopoulou, E, additional, and Rogdakis, E, additional
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- 2003
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25. Cellularity and enzymatic activity of adipose tissue in the Karagouniko dairy breed of sheep from birth to maturity
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Rogdakis, E., primary, Charismiadou, M., additional, Orphanos, S., additional, Panopoulou, E., additional, and Bizelis, I., additional
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- 1997
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26. Carcass composition, size of fat cells and NADPH-generating dehydrogenases activity in adipose tissue of the fat-tailed Chios and the thin-tailed Karagouniko sheep breed.
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Panopoulou, E., Deligeorgis, S. G., Papadimitriou, T., and Rogdakis, E.
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- 1989
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27. Enabling problem based learning through web 2.0 technologies: PBL 2.0
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Tambouris, E., Panopoulou, E., Konstantinos Tarabanis, Ryberg, T., Buus, L., Peristeras, V., Lee, D., and Porwol, L.
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Web 2.0 ,learning ,e-learning platform ,Collaborative Learning ,PBL ,Problem Based Learning ,ComputingMilieux_COMPUTERSANDEDUCATION ,PBL 2.0 - Abstract
Advances in Information and Communications Technology (ICT), particularly the so-called Web 2.0, are affecting all aspects of our life: how we communicate, how we shop, how we socialise, and how we learn. Facilitating learning through the use of ICT, also known as eLearning, is a vital part of modern educational systems. Established pedagogical strategies, such as Problem Based Learning (PBL), are being adapted for online use in conjunction with modern Web 2.0 technologies and tools. However, even though Web 2.0 and progressive social-networking technologies are automatically associated with ideals such as collaboration, sharing, and active learning, it is also possible to use them in a very conservative, teacher-centred way limiting thus their impact. In this paper, we present a PBL 2.0 framework, i.e., a framework combining PBL practices with Web 2.0 technologies. More specifically, we (a) explain the theoretical considerations and construct the PBL 2.0 framework; (b) develop a learning platform to support the PBL 2.0 framework approach; and (c) apply PBL 2.0 in a real-world setting for lecturing University undergraduate students. Pilot results are encouraging as overall satisfaction with the developed platform and good acceptance of the new learning practices is observed. Although the full potential of PBL 2.0 could not be achieved due to different institutional and cultural obstacles, authors believe that PBL 2.0 framework provides good guidance for designing and implementing a PBL course.
28. ERBIN is a new SARA-interacting protein: Competition between SARA and SMAD2 and SMAD3 for binding to ERBIN
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Sflomos, G., Kostaras, E., Panopoulou, E., Pappas, N., Kyrkou, A., Politou, A. S., Fotsis, T., and Murphy, C.
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Peptide Fragments/metabolism ,Transcriptional Activation ,animal structures ,Smad3 Protein/*metabolism ,Serine Endopeptidases/chemistry/genetics/*metabolism ,Luciferases, Renilla/biosynthesis/genetics ,Smad2 Protein/*metabolism ,Adaptor Proteins, Signal Transducing/chemistry/genetics/*metabolism ,Response Elements ,Cell Line ,Intracellular Signaling Peptides and Proteins/chemistry/genetics/*metabolism ,Mice ,Protein Transport ,Genes, Reporter ,Cell Nucleus/metabolism ,Animals ,Humans ,Protein Interaction Domains and Motifs ,RNA Interference ,biological phenomena, cell phenomena, and immunity ,Activins/metabolism ,Transforming Growth Factor beta/metabolism ,Protein Binding - Abstract
SARA, an early endosomal protein, plays a key role in TGFβ signalling, as it presents SMAD2 and SMAD3 for phosphorylation by the activated TGFβ receptors. Here, we show that ERBIN is a new SARA-interacting protein that can be recruited by SARA to early endosomes. ERBIN was recently shown to bind and segregate phosphorylated SMAD2 and SMAD3 (SMAD2/3) in the cytoplasm, thereby inhibiting SMAD2/3-dependent transcription. SARA binds to ERBIN using a new domain, which we have called the ERBID (ERBIN-binding domain), whereas ERBIN binds to SARA using a domain (amino acids 1208-1265) that also interacts with SMAD2 and SMAD3, which we have called the SSID (SARA- and SMAD-interacting domain). We additionally show that SARA competes with SMAD2/3 for binding to ERBIN. In agreement, overexpression of SARA or the ERBID peptide reverses the inhibitory effect of ERBIN on SMAD2/3-dependent transcription. Taken together, these data suggest that the response of cells to TGFβ and activin A can be influenced by the relative concentrations of SARA, ERBIN and SMAD2/3. © 2011. Published by The Company of Biologists Ltd.
29. The effects of asymmetric volatility shocks on equity and foreign exchange rate interactions
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Thomas Flavin, Panopoulou, E., Pantelidis, T., and Unalmis, D.
30. Volume of blood suctioned during vacuum-assisted breast biopsy predicts later hematoma formation
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Panopoulou Effrosyni, Flessas Ioannis, Safioleas Panagiotis, Michalopoulos Nikolaos V, Giannakopoulou Georgia, Chrysikos Dimosthenis, Domeyer Philip, Sergentanis Theodoros N, Zagouri Flora, Bletsa Garifallia, and Zografos George C
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Medicine ,Biology (General) ,QH301-705.5 ,Science (General) ,Q1-390 - Abstract
Abstract Background To evaluate whether the volume of blood suctioned during vacuum-assisted breast biopsy (VABB) is associated with hematoma formation and progression, patient's age and histology of the lesion. Findings 177 women underwent VABB according to standardized protocol. The volume of blood suctioned and hematoma formation were noted at the end of the procedure, as did the subsequent development and progression of hematoma. First- and second-order logistic regression was performed, where appropriate. Cases with hematoma presented with greater volume of blood suctioned (63.8 ± 44.7 cc vs. 17.2 ± 32.9 cc; p < 0.001, Mann-Whitney-Wilcoxon test for independent samples, MWW); the likelihood of hematoma formation was increasing till a volume equal to 82.6 cc, at which the second-order approach predicts a maximum. The volume of blood suctioned was positively associated with the duration of the procedure (Spearman's rho = 0.417, p < 0.001); accordingly, hematoma formation was also positively associated with the latter (p = 0.004, MWW). The volume of blood suctioned was not associated with patients' age, menopausal status and histopathological diagnosis. Conclusion The likelihood of hematoma is increasing along with increasing amount of blood suctioned, reaching a plateau approximately at 80 cc of blood lost.
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- 2010
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31. Breast ductal endoscopy: how many procedures qualify?
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Papalabros Alexandros, Filippakis George, Flessas John, Bletsa Garifallia, Chrysikos Dimosthenis, Panopoulou Effrosyni, Giannakopoulou Georgia, Sergentanis Theodoros N, Zagouri Flora, Bramis Kostas J, and Zografos George C
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Medicine ,Biology (General) ,QH301-705.5 ,Science (General) ,Q1-390 - Abstract
Abstract Background Breast ductal endoscopy is a relatively new diagnostic method with ever growing importance in the work-up of patients with bloody nipple discharge. The ability to perform ductal endoscopy is very important and useful for breast fellows. Learning curve in breast ductal endoscopy remains a terra incognita, since no systematic studies have addressed this topic. The purpose of this study is to determine the point (number of procedures during training) beyond which ductal endoscopy is successfully performed. Findings Ten breast fellows received training in our Breast Unit. For the training process, an ex vivo model was adopted. Fellows were trained on 20 surgical specimens derived from modified radical mastectomy for breast cancer. The target of the education program was to acquire proficiency in performing ductoscopy. The achievement of four consecutively successful ductal endoscopies was determined as the point beyond which proficiency had been achieved. The number of procedures needed for the achievement of proficiency as defined above ranged between 9 and 17 procedures. The median value was 13 procedures; i.e. 50% of trainees had achieved proficiency at the 13th procedure or earlier. Conclusion These pilot findings point to approximately 13 procedures as a point beyond which ductal endoscopy is successfully performed; studies on a larger number of fellows are nevertheless needed. Further research, focusing on the learning curves of different training models of ductal endoscopy, seems desirable.
- Published
- 2009
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32. Serum hepatitis B virus RNA detectability, composition and clinical significance in patients with ab initio hepatitis B e antigen negative chronic hepatitis B.
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Laras A, Papatheodoridi M, Panopoulou E, Papatheodoridis GV, Hadziyannis SJ, and Hadziyannis E
- Subjects
- Antiviral Agents therapeutic use, DNA, Viral genetics, Hepatitis B e Antigens, Humans, RNA, Retrospective Studies, Hepatitis B virus genetics, Hepatitis B, Chronic drug therapy
- Abstract
Background: Serum hepatitis B virus (HBV) RNA is a surrogate biomarker for intrahepatic covalently closed circular DNA (cccDNA) transcriptional activity and persistence. In this retrospective study, we investigated its presence, levels and composition in ab initio Hepatitis B e antigen (HBeAg) negative chronically infected patients and examined possible associations with disease activity and the outcome of nucleos(t)ide analogue (NA) discontinuation., Methods: We developed a sensitive real time polymerase chain reaction (RT-PCR) for the specific detection of HBV pregenomic RNA (pgRNA) and precore (preC) mRNA and analyzed 220 serum specimens, 160 under NA treatment, from 116 Greek patients initially negative for HBeAg., Results: HBV pgRNA was detected in 31% and preC mRNA in 15% of samples, at lower levels representing a small fraction (3.4%) of total core promoter produced transcripts. In the absence of NAs, pgRNA was detected in 57% of samples with median value of 5.19 (2.61-8.35) log
10 cp/mL, at lower levels than HBV DNA and correlated significantly with ALT (r = 0.764) and serum HBV DNA (r = 0.906). A wide range of HBV DNA/pgRNA ratio was observed with significant inter- and intra-patient variation. During NA treatment, pgRNA displayed low detectability (22%) and variable levels, median 3.97 (2.30- 8.13) log10 cp/mL, as well as, a significant inverse correlation with the duration of treatment (r = - 0.346, p < 0.01). In 74 events of NA discontinuation, end-of-treatment pgRNA-positive compared to pgRNA-negative cases, experienced more frequently virological (p = 0.016) and clinical (p = 0.011) relapse., Conclusions: In genotype D ab initio HBeAg negative patients, serum HBV RNA is primarily composed of pgRNA plus a minor fraction of preC mRNA transcripts. Serum pgRNA is associated with disease activity, suggesting lysis of infected hepatocytes as a possible source of serum HBV RNA in untreated patients and in the early phase of NA treatment. During long term NA treatment, detectable serum pgRNA predicts viral rebound and clinical relapse following treatment discontinuation and may thus serve as a marker for the decision of cessation of therapy., (© 2022. The Author(s).)- Published
- 2022
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33. Primary Duodenal Melanoma: Challenges in Diagnosis and Management of a Rare Entity.
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Dimopoulou K, Dimopoulou A, Dimopoulou D, Panopoulou E, Zacharatou A, Patapis P, and Zavras N
- Subjects
- Female, Humans, Aged, Endoscopy, Duodenum surgery, Duodenum pathology, Melanoma diagnosis, Melanoma surgery
- Abstract
Primary melanoma of the duodenum is an extremely rare, aggressive and life-threatening malignant neoplasm. Published data regarding the effectiveness of current treatment strategies is limited, and our knowledge relies mostly on sporadic case reports. The diagnosis of primary duodenal melanoma is challenging and is based on the patient's medical history and findings from physical examination and radiological and endoscopic imaging as well as proper and careful pathological examinations of the tumor. Despite the many advances in cancer treatment, the prognosis for patients with this type of melanoma remains extremely poor. Delayed diagnosis at advanced disease stage, the general aggressive behavior of this neoplasm, the technical difficulty in achieving complete surgical resection, along with the rich vascular and lymphatic drainage of the intestinal mucosa, all have a negative impact on patients' outcome. In the present review, we aimed to collect and summarize the currently available data in the literature regarding the pathogenesis, clinical features, diagnosis, management and long-term outcomes of this rare, malignant tumor, in order to expand knowledge of its biological behavior and investigate optimal therapeutic options for these patients. Additionally, we present our experience of a case involving a 73-year-old female with primary duodenal melanoma, who was successfully treated with complete surgical resection.
- Published
- 2022
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34. Embryonic stem cells are devoid of macropinocytosis, a trafficking pathway for activin A in differentiated cells.
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Kostopoulou N, Bellou S, Bagli E, Markou M, Kostaras E, Hyvönen M, Kalaidzidis Y, Papadopoulos A, Chalmantzi V, Kyrkou A, Panopoulou E, Fotsis T, and Murphy C
- Subjects
- Cell Differentiation, Embryonic Stem Cells, Endocytosis, Humans, Activins, Endothelial Cells
- Abstract
Ligand-receptor complexes formed at the plasma membrane are internalised via various endocytic pathways that influence the ultimate signalling output by regulating the selection of interaction partners by the complex along the trafficking route. We report that, in differentiated cells, activin A-receptor complexes are internalised via clathrin-mediated endocytosis (CME) and macropinocytosis (MP), whereas in human embryonic stem cells (hESCs) internalisation occurs via CME. We further show that hESCs are devoid of MP, which becomes functional upon differentiation towards endothelial cells through mesoderm mediators. Our results reveal, for the first time, that MP is an internalisation route for activin A in differentiated cells, and that MP is not active in hESCs and is induced as cells differentiate., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2021. Published by The Company of Biologists Ltd.)
- Published
- 2021
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35. The INTEND 1 randomized controlled trial of duct endoscopy as an indicator of margin excision in breast conservation surgery.
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Gui G, Panopoulou E, Tang S, Twelves D, Kabir M, Ward A, Montgomery C, Nerurkar A, Osin P, and Isacke CM
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- Breast, Endoscopy, Female, Humans, Mastectomy, Segmental, Middle Aged, Breast Neoplasms diagnosis, Breast Neoplasms surgery, Carcinoma, Ductal, Breast surgery
- Abstract
Purpose: With early detection, breast conservation surgery with adequate surgical margins is the standard of care. The aim of this study was to evaluate the use of pre-operative duct endoscopy (DE) to target surgical resection, improve adequate margins and reduce re-excision operations., Methods: Women with DCIS, stage I and II breast cancer suitable for breast conservation were randomized to DE-assisted wide local excision versus standard wide local excision (without DE). The primary endpoint was margin re-excision rates between the two groups. Secondary end points were: (i) volume differences of the surgical specimen; (ii) whether an extensive in situ component (EIC) influenced successful DE-guided resection., Results: 78 women were randomized: 44 patients to no-DE and 34 patients to the DE group. The median age was 59 (49-65) and 56 (48-64) years in the two groups respectively with mean follow-up of 9.1 (4.2-11.1) years. There were 23 positive findings in 17 women in 30 successful DE procedures (17/30 = 56.7%). The surgical specimen volume, no-DE (17 [IQR 10-29] cm
3 ) and DE 20 [IQR 12-28] cm3 ), did not differ, p = 0.377. The overall re-excision rate was 20/78 (26%), 9 (20%) and 11 (32% in the no-DE and DE groups, respectively, p = 0.233., Conclusions: This randomized clinical trial was limited by incomplete accrual. DE did not contribute to improved margin excision rates whether a target lesion was visualized or not. The presence of EIC did not improve efficacy of DE.- Published
- 2021
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36. In vivo biochemical investigation of spermatogenic status: 1H-MR spectroscopy of testes with nonobstructive azoospermia.
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Ntorkou A, Tsili AC, Astrakas L, Goussia A, Panopoulou E, Sofikitis N, and Argyropoulou MI
- Subjects
- Adult, Azoospermia metabolism, Azoospermia pathology, Azoospermia surgery, Case-Control Studies, Choline metabolism, Creatine metabolism, Glutamic Acid metabolism, Humans, Inositol metabolism, Lipid Metabolism, Male, Middle Aged, Prospective Studies, Retrospective Studies, Sperm Retrieval, Spermatozoa pathology, Testis metabolism, Testis pathology, Testis surgery, Azoospermia diagnostic imaging, Proton Magnetic Resonance Spectroscopy methods, Spermatogenesis, Testis diagnostic imaging
- Abstract
Objectives: To evaluate the biochemical milieu in testes with nonobstructive azoospermia (NOA) by using proton MR spectroscopy (1H-MRS) in detecting differences in testicular metabolites between histological stages of NOA and in assessing the possible presence of spermatozoa before microdissection testicular sperm extraction (mTESE)., Methods: Forty-nine NOA men and fifty age-matched controls were included in this prospective study. A single-voxel point-resolved spectroscopy sequence with TR/TE (2000/25 ms) was used. NOA testes were classified using the higher Johnsen score (hJS) (group 1, hJS ≥ 8; and group 2, hJS < 8). Nonparametric statistical tests were used to assess differences in normalized metabolite concentrations, defined as ratios of the metabolite concentrations versus creatine concentration between (a) NOA and controls, (b) NOA groups, and (c) NOA with positive and negative sperm retrieval., Results: Normalized concentrations of total choline (median 0.396 vs 1.09 mmol/kg, p = 0.002), myo-inositol (median 1.985 vs 3.19 mmol/kg, p = 0.002), and total lipids and macromolecules (TLM) resonating at 0.9 ppm (median 0.962 vs 2.43 mmol/kg, p = 0.024), 1.3 ppm (median 4.88 vs 10.7 mmol/kg, p = 0.043), and 2.0 ppm (median 2.33 vs 5.96 mmol/kg, p = 0.007) were reduced in NOA testes compared with controls. Decreased concentrations of TLM 2.0 (median 3.755 vs 0.436 mmol/kg, p = 0.043) were found in group 2 compared with group 1. Increased normalized concentrations of glutamate were observed in NOA testes with failed sperm retrieval (median 0.321 vs 0.000 mmol/kg, p = 0.028)., Conclusions: 1H-MRS provides metabolic information about the testis in NOA patients and assesses spermatogenic status before mTESE., Key Points: • NOA testes differed from age-matched controls, in terms of reduced normalized concentrations of tChol, mI, and lipids. • TLM 2.0 peaks were found useful in the identification of NOA testes with the presence of foci of advanced spermatogenesis up to the haploid gamete stage. • Glu proved a reliable metabolic signature of spermatogenesis in NOA population by assessing the possible presence of sperm after mTESE.
- Published
- 2020
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37. Immunohistochemical Profile of Tumor Suppressor Proteins RASSF1A and LATS1/2 in Relation to p73 and YAP Expression, of Human Inflammatory Bowel Disease and Normal Intestine.
- Author
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Nterma P, Panopoulou E, Papadaki-Petrou E, and Assimakopoulou M
- Subjects
- Adaptor Proteins, Signal Transducing analysis, Adaptor Proteins, Signal Transducing biosynthesis, Adult, Aged, Aged, 80 and over, Female, Humans, Immunohistochemistry, Male, Middle Aged, Protein Serine-Threonine Kinases analysis, Protein Serine-Threonine Kinases biosynthesis, Transcription Factors analysis, Transcription Factors biosynthesis, Tumor Protein p73 analysis, Tumor Protein p73 biosynthesis, YAP-Signaling Proteins, Young Adult, Biomarkers analysis, Inflammatory Bowel Diseases metabolism, Inflammatory Bowel Diseases pathology, Intestine, Large metabolism, Tumor Suppressor Proteins analysis, Tumor Suppressor Proteins biosynthesis
- Abstract
The intestinal neoplastic transformation is a possible risk of chronic inflammatory bowel disease (IBD). Previous evidence in mice IBD provides a role for the RAS-association domain family tumor suppressor protein 1 A (RASSF1A), in the repairing process following mucosa epithelium damage, through cooperation with the HIPPO-signaling molecules p73, and YAP. HIPPO pathway which has been implicated in stem cell activity includes as key components for signal transduction the large tumor suppressor homology Ser/Thr kinases LATS1/2. The aim of this study was to assess immunohistochemically, using specific antibodies, the RASSF1A and LATS1/2 expression patterns in a cohort of patients with IBD including 52 ulcerative colitis (UC), 24 Crohn's disease (CD) and 24 IBD unclassified (IBD-U), compared with normal intestine from non-IBD patients (control group). The relationship between subtypes of IBD and RASSF1A and LATS1/2 expression, both individually and related to p73 and YAP/pYAP(Ser127) proteins was also investigated. Quantitative analyses of the immunohistochemical findings in mucosa cells revealed a significantly decreased expression in UC and IBD-U for RASSF1A expression and a significantly elevated expression in UC, IBD-U, and CD for LATS1/2 expression compared with normal mucosa (P < 0.05). However, ROC curve analysis showed that only LATS1/2 could differentiate IBD from control group. RASSF1A expression was significantly correlated with LATS1/2 in UC with dysplasia (P < 0.0001), and p73 in UC (P < 0.001), and IBD-U (P < 0.02). The expression of all proteins did not differ significantly between subtypes of IBD (P ≥ 0.05). RASSF1A-LATS1/2 co-expression was mainly observed in IBD samples. These findings suggest that tumor suppression proteins RASSF1A and LATS1/2 may be involved in the pathogenesis of human IBD and imply a potential cooperation of RASSF1A, and HIPPO signaling pathways in human bowel inflammation.
- Published
- 2020
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38. Searching HPV genome for methylation sites involved in molecular progression to cervical precancer.
- Author
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Kottaridi C, Leventakou D, Pouliakis A, Pergialiotis V, Chrelias G, Patsouri E, Zacharatou A, Panopoulou E, Damaskou V, Sioulas V, Chrelias C, Kalantaridou S, and Panayiotides IG
- Abstract
Background: Human Papilloma Virus has been considered as the main cause for cervical cancer. In this study we investigated epigenetic changes and especially methylation of specific sites of HPV genome. The main goal was to correlate methylation status with histological grade as well as to determine its accuracy in predicting the disease severity by establishing optimum methylation cutoffs. Methods : In total, sections from 145 cases genotyped as HPV16 were obtained from formalin- fixed, paraffin-embedded tissue of cervical biopsies, conization or hysterectomy specimens. Highly accurate pyrosequencing of bisulfite converted DNA, was used to quantify the methylation percentages of UTR promoter, enhancer and 5' UTR, E6 CpGs 494, 502, 506 and E7 CpGs 765, 780, 790. The samples were separated in different groupings based on the histological outcome. Statistical analysis was performed by SAS 9.4 for Windows and methylation cutoffs were identified by MATLAB programming language. Results: The most important methylation sites were at the enhancer and especially UTR 7535 and 7553 sites. Specifically for CIN3+ (i.e. HSIL or SCC) discrimination, a balanced sensitivity vs. specificity (68.1%, 66.2% respectively) with positive predictive value (PPV) and negative predictive value (NPV) (66.2%, 68.2% respectively) was achieved for UTR 7535 methylation of 6.1% cutoff with overall accuracy 67.1%, while for UTR 7553 a sensitivity 60.9%, specificity 69.0%, PPV=65.6%, NPV=64.5% and overall accuracy=65.0% at threshold 10.1% was observed. Conclusion: Viral HPV16 genome was found methylated in NF-1 binding sites of UTR in cases with high grade disease. Methylation percentages of E6 and E7 CpG sites were elevated at the cancer group., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.
- Published
- 2019
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39. Diffusion tensor imaging parameters in testes with nonobstructive azoospermia.
- Author
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Tsili AC, Ntorkou A, Goussia A, Astrakas L, Panopoulou E, Sofikitis N, and Argyropoulou MI
- Subjects
- Adult, Case-Control Studies, Humans, Image Processing, Computer-Assisted, Infertility, Male diagnostic imaging, Male, Middle Aged, Retrospective Studies, Spermatogenesis, Spermatozoa, Azoospermia diagnostic imaging, Diffusion Tensor Imaging, Magnetic Resonance Imaging, Sperm Retrieval, Testis diagnostic imaging
- Abstract
Background: The development of noninvasive imaging parameters having the capacity to identify the population of men with nonobstructive azoospermia (NOA) where a successful sperm retrieval outcome is of great clinical significance., Purpose/hypothesis: To assess differences of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in NOA testes with impaired spermatogenesis and the possible association with the presence of spermatozoa after testicular sperm extraction (TESE)., Study Type: Retrospective., Population: Twenty NOA men (35 testes) and 21 age-matched controls (36 testes)., Field Strength/sequence: 1.5T, T
1 WI-SE T2 WI-FSE FS SS-EP-DTI., Assessments: The MRI data were analyzed by two radiologists in consensus. The average ADC and FA of testicular parenchyma was measured. NOA testes were classified as NOA with higher Johnsen score (JS) ≥8 (group 1) and JS <8 (group 2)., Statistical Tests: Parametric and nonparametric statistical tests were used to compare ADC and FA between NOA groups and normal testes (group 3) and to evaluate a possible association with the presence of spermatozoa after TESE., Results: Differences in ADC were found between groups 1 and 2 (P = 0.043) and groups 2 and 3 (P = 0.004), but not between groups 1 and 3 (P = 0.418). Higher values of FA were found both in NOA testes with JS ≥8 (P < 0.001) and JS <8 (P < 0.001) compared to controls. ADC (P = 0.096) and FA (P = 0.516) did not demonstrate differences in NOA testes with or without spermatozoa at TESE., Data Conclusion: Both ADC and FA are increased in NOA testes compared to a normal population. ADC was proven to be a more useful diagnostic adjunct tool in the identification of the population of NOA men with foci of advanced spermatogenesis. However, DTI parameters were not predictive of sperm retrieval after TESE., Level of Evidence: 4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1318-1325., (© 2018 International Society for Magnetic Resonance in Medicine.)- Published
- 2018
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40. Clonal evolution of colorectal cancer in a patient with serially resected metastases and liquid biopsies: a case report and discussion of the literature.
- Author
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Kastrisiou M, Zarkavelis G, Kampletsas E, Panopoulou E, Goussia A, Nasioulas G, Papadopoulou E, Tsaousi C, and Pentheroudakis G
- Abstract
Background: Metastatic colorectal cancer represents a striking example of clonal heterogeneity and tumour evolution, which generates acquired resistance to therapy. Once hard to perform, the study of clonal heterogeneity is now significantly aided by the use of liquid biopsies., Method: We herein report a case of a patient with colorectal cancer and serial development of multiple metastases which were all resected and genotyped. A rare point mutation was identified in the primary tumour (but not in any of the organ metastatic sites), as well as in the first and the last out of three consecutive liquid biopsies. The review of the literature offered some insight in the evolution of the patient's tumour and general directions on how to interpret liquid biopsy results., Conclusions: This patient case emphasises the need for large prospective studies designed to bridge liquid biopsy data with useful clinical endpoints, in order to optimally integrate this revolutionary tool in everyday practice., Competing Interests: Competing interests: GN and EP are employees of GeneKor Medical SA, Athens, Greece.
- Published
- 2018
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41. BCL2L12 protein overexpression is associated with favorable outcome in diffuse large B-cell lymphoma patients in the rituximab era.
- Author
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Papageorgiou SG, Kontos CK, Foukas PG, Panopoulou E, Vasilatou D, Rapti SM, Gkontopoulos K, Bazani E, Panayiotides IG, Dimitriadis G, Scorilas A, and Pappa V
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Biomarkers, Pharmacological metabolism, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Gene Expression Regulation, Neoplastic, HL-60 Cells, Humans, Lymphoma, Large B-Cell, Diffuse genetics, Lymphoma, Large B-Cell, Diffuse mortality, Muscle Proteins metabolism, Prognosis, Proto-Oncogene Proteins c-bcl-2 metabolism, Rituximab administration & dosage, Survival Analysis, Treatment Outcome, Up-Regulation genetics, Lymphoma, Large B-Cell, Diffuse diagnosis, Lymphoma, Large B-Cell, Diffuse drug therapy, Muscle Proteins genetics, Proto-Oncogene Proteins c-bcl-2 genetics, Rituximab therapeutic use
- Published
- 2016
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42. Cross-state disparities in US health care expenditures.
- Author
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Panopoulou E and Pantelidis T
- Subjects
- Health Services economics, Humans, United States, Economics, Medical statistics & numerical data, Health Expenditures statistics & numerical data, Health Services statistics & numerical data
- Abstract
This study examines the degree of convergence in health care expenditures among the US states from 1980 to 2004. Our results suggest that the US states form two clubs with specific geographical characteristics that converge to different equilibria. We also extend our analysis to investigate the cross-state disparities in nine major components of health expenditures. Our findings provide evidence for full convergence for only two components, namely 'physician and other professional services' and 'home health care'. However, for the remaining components, we can still identify various convergence clubs., (Copyright © 2012 John Wiley & Sons, Ltd.)
- Published
- 2013
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43. ERBIN is a new SARA-interacting protein: competition between SARA and SMAD2 and SMAD3 for binding to ERBIN.
- Author
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Sflomos G, Kostaras E, Panopoulou E, Pappas N, Kyrkou A, Politou AS, Fotsis T, and Murphy C
- Subjects
- Activins metabolism, Adaptor Proteins, Signal Transducing chemistry, Adaptor Proteins, Signal Transducing genetics, Animals, Cell Line, Cell Nucleus metabolism, Genes, Reporter, Humans, Intracellular Signaling Peptides and Proteins chemistry, Intracellular Signaling Peptides and Proteins genetics, Luciferases, Renilla biosynthesis, Luciferases, Renilla genetics, Mice, Peptide Fragments metabolism, Protein Binding, Protein Interaction Domains and Motifs, Protein Transport, RNA Interference, Response Elements, Serine Endopeptidases chemistry, Serine Endopeptidases genetics, Transcriptional Activation, Transforming Growth Factor beta metabolism, Adaptor Proteins, Signal Transducing metabolism, Intracellular Signaling Peptides and Proteins metabolism, Serine Endopeptidases metabolism, Smad2 Protein metabolism, Smad3 Protein metabolism
- Abstract
SARA, an early endosomal protein, plays a key role in TGFβ signalling, as it presents SMAD2 and SMAD3 for phosphorylation by the activated TGFβ receptors. Here, we show that ERBIN is a new SARA-interacting protein that can be recruited by SARA to early endosomes. ERBIN was recently shown to bind and segregate phosphorylated SMAD2 and SMAD3 (SMAD2/3) in the cytoplasm, thereby inhibiting SMAD2/3-dependent transcription. SARA binds to ERBIN using a new domain, which we have called the ERBID (ERBIN-binding domain), whereas ERBIN binds to SARA using a domain (amino acids 1208-1265) that also interacts with SMAD2 and SMAD3, which we have called the SSID (SARA- and SMAD-interacting domain). We additionally show that SARA competes with SMAD2/3 for binding to ERBIN. In agreement, overexpression of SARA or the ERBID peptide reverses the inhibitory effect of ERBIN on SMAD2/3-dependent transcription. Taken together, these data suggest that the response of cells to TGFβ and activin A can be influenced by the relative concentrations of SARA, ERBIN and SMAD2/3., (@ 2011. Published by The Company of Biologists Ltd)
- Published
- 2011
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44. Volume of blood suctioned during vacuum-assisted breast biopsy predicts later hematoma formation.
- Author
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Zagouri F, Sergentanis TN, Domeyer P, Chrysikos D, Giannakopoulou G, Michalopoulos NV, Safioleas P, Flessas I, Panopoulou E, Bletsa G, and Zografos GC
- Abstract
Background: To evaluate whether the volume of blood suctioned during vacuum-assisted breast biopsy (VABB) is associated with hematoma formation and progression, patient's age and histology of the lesion., Findings: 177 women underwent VABB according to standardized protocol. The volume of blood suctioned and hematoma formation were noted at the end of the procedure, as did the subsequent development and progression of hematoma. First- and second-order logistic regression was performed, where appropriate. Cases with hematoma presented with greater volume of blood suctioned (63.8 +/- 44.7 cc vs. 17.2 +/- 32.9 cc; p < 0.001, Mann-Whitney-Wilcoxon test for independent samples, MWW); the likelihood of hematoma formation was increasing till a volume equal to 82.6 cc, at which the second-order approach predicts a maximum. The volume of blood suctioned was positively associated with the duration of the procedure (Spearman's rho = 0.417, p < 0.001); accordingly, hematoma formation was also positively associated with the latter (p = 0.004, MWW). The volume of blood suctioned was not associated with patients' age, menopausal status and histopathological diagnosis., Conclusion: The likelihood of hematoma is increasing along with increasing amount of blood suctioned, reaching a plateau approximately at 80 cc of blood lost.
- Published
- 2010
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45. VEGF autoregulates its proliferative and migratory ERK1/2 and p38 cascades by enhancing the expression of DUSP1 and DUSP5 phosphatases in endothelial cells.
- Author
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Bellou S, Hink MA, Bagli E, Panopoulou E, Bastiaens PI, Murphy C, and Fotsis T
- Subjects
- Cell Movement physiology, Cell Nucleus drug effects, Cell Nucleus metabolism, Cell Proliferation, Cells, Cultured, Drug Interactions, Dual Specificity Phosphatase 1 genetics, Dual Specificity Phosphatase 1 metabolism, Dual-Specificity Phosphatases genetics, Dual-Specificity Phosphatases metabolism, Humans, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, Phosphorylation, Tissue Distribution, Transcription, Genetic physiology, Umbilical Veins cytology, Up-Regulation physiology, Vascular Endothelial Growth Factor A pharmacology, p38 Mitogen-Activated Protein Kinases metabolism, Endothelial Cells cytology, Endothelial Cells enzymology, Extracellular Signal-Regulated MAP Kinases metabolism, Homeostasis, Mitogen-Activated Protein Kinase Phosphatases metabolism, Vascular Endothelial Growth Factor A metabolism
- Abstract
Vascular endothelial growth factor (VEGF) is a key angiogenic factor that regulates proliferation and migration of endothelial cells via phosphorylation of extracellular signal-regulated kinase-1/2 (ERK1/2) and p38, respectively. Here, we demonstrate that VEGF strongly induces the transcription of two dual-specificity phosphatase (DUSP) genes DUSP1 and DUSP5 in endothelial cells. Using fluorescence microscopy, fluorescence lifetime imaging (FLIM), and fluorescence cross-correlation spectroscopy (FCCS), we found that DUSP1/mitogen-activated protein kinases phosphatase-1 (MKP-1) was localized in both the nucleus and cytoplasm of endothelial cells, where it existed in complex with p38 (effective dissociation constant, K(D)(eff), values of 294 and 197 nM, respectively), whereas DUSP5 was localized in the nucleus of endothelial cells in complex with ERK1/2 (K(D)(eff) 345 nM). VEGF administration affected differentially the K(D)(eff) values of the DUSP1/p38 and DUSP5/ERK1/2 complexes. Gain-of-function and lack-of-function approaches revealed that DUSP1/MKP-1 dephosphorylates primarily VEGF-phosphorylated p38, thereby inhibiting endothelial cell migration, whereas DUSP5 dephosphorylates VEGF-phosphorylated ERK1/2 inhibiting proliferation of endothelial cells. Moreover, DUSP5 exhibited considerable nuclear anchoring activity on ERK1/2 in the nucleus, thereby diminishing ERK1/2 export to the cytoplasm decreasing its further availability for activation.
- Published
- 2009
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46. Breast ductal endoscopy: how many procedures qualify?
- Author
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Zagouri F, Sergentanis TN, Giannakopoulou G, Panopoulou E, Chrysikos D, Bletsa G, Flessas J, Filippakis G, Papalabros A, Bramis KJ, and Zografos GC
- Abstract
Background: Breast ductal endoscopy is a relatively new diagnostic method with ever growing importance in the work-up of patients with bloody nipple discharge. The ability to perform ductal endoscopy is very important and useful for breast fellows. Learning curve in breast ductal endoscopy remains a terra incognita, since no systematic studies have addressed this topic. The purpose of this study is to determine the point (number of procedures during training) beyond which ductal endoscopy is successfully performed., Findings: Ten breast fellows received training in our Breast Unit. For the training process, an ex vivo model was adopted. Fellows were trained on 20 surgical specimens derived from modified radical mastectomy for breast cancer. The target of the education program was to acquire proficiency in performing ductoscopy. The achievement of four consecutively successful ductal endoscopies was determined as the point beyond which proficiency had been achieved. The number of procedures needed for the achievement of proficiency as defined above ranged between 9 and 17 procedures. The median value was 13 procedures; i.e. 50% of trainees had achieved proficiency at the 13th procedure or earlier., Conclusion: These pilot findings point to approximately 13 procedures as a point beyond which ductal endoscopy is successfully performed; studies on a larger number of fellows are nevertheless needed. Further research, focusing on the learning curves of different training models of ductal endoscopy, seems desirable.
- Published
- 2009
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47. Pain during vacuum-assisted breast biopsy: are there any predictors?
- Author
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Zografos GC, Zagouri F, Sergentanis TN, Nonni A, Domeyer P, Koulocheri D, Flessas I, Panopoulou E, Chrysikos D, and Bramis J
- Subjects
- Adult, Aged, Aged, 80 and over, Biopsy, Needle methods, Blood Loss, Surgical, Female, Hematoma etiology, Humans, Luteal Phase, Menopause, Middle Aged, Multivariate Analysis, Pain diagnosis, Pain Measurement, Vacuum, Biopsy, Needle adverse effects, Breast Neoplasms pathology, Pain etiology
- Abstract
Introduction: To assess the putative predictors that may be implicated in the pain experienced during stereotactic vacuum-assisted breast biopsy (VABB)., Materials and Methods: One hundred and thirty-five consecutive women with microcalcifications underwent VABB on the Fischer's table. The visual analogue scale was used to measure the degree of the "average pain" (AP)., Results: At the univariable analysis, the AP was positively associated with the duration of the procedure, the diagnosis of malignant/preinvasive lesions and the volume of blood lost. Although menopausal status was not associated with the AP, within the premenopausal subpopulation, luteal phase was associated with higher VAS score. These findings also persisted at the multivariable ordinal logistic regression model. However, the mean experienced pain was associated neither with the volume of tissue excised nor with the hematoma formation, nor with patients' age., Conclusion: The aforementioned factors were independent positive predictors of the mean experienced pain during VABB.
- Published
- 2008
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48. Minimizing underestimation rate of microcalcifications excised via vacuum-assisted breast biopsy: a blind study.
- Author
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Zografos GC, Zagouri F, Sergentanis TN, Nonni A, Koulocheri D, Fotou M, Panopoulou E, Pararas N, Fotiadis C, and Bramis J
- Subjects
- Breast Neoplasms surgery, False Negative Reactions, Female, Humans, Precancerous Conditions surgery, Stereotaxic Techniques, Vacuum, Biopsy methods, Breast Neoplasms diagnosis, Precancerous Conditions diagnosis
- Abstract
Purpose: The main disadvantage of Vacuum Assisted Breast Biopsy (VABB) is the probability of underestimating atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS). This study evaluates a modified way of performing VABB., Methods: 266 women with microcalcifications graded BI-RADS 3&4 underwent VABB (11G) on the Fischer's table. 133 women were allocated to the "standard" protocol and 24 cores were obtained (1 offset-main target and one additional offset). 133 women were randomly allocated to the "extended" protocol and 96 cores were excised (one offset- main target and 7 peripheral offsets). A preoperative diagnosis was established, and the removed volume was calculated. When precursor or malignant lesions were diagnosed, open surgery was performed. A second pathologist, blind to the preoperative results and to the protocol made the postoperative diagnosis. The discrepancy between preoperative and postoperative diagnoses was evaluated., Results: When the standard protocol was applied, the underestimation rate for preoperative ADH, lobular neoplasia (LN), DCIS was 16.7%, 50% and 14.3% correspondingly. In the extended protocol, no underestimation was present in LN, ADH, but the underestimation rate for DCIS was 6.3%. In the extended protocol, no precursor/malignant tissue was left after VABB in all ADH cases, in 87.5% of LN cases, in 73.3% of DCIS, and in 50% of invasive carcinomas. The volume excised was 2.33 +/- 0.60 cc and 6.14 +/- 1.30 cc for the standard and the extended protocol, respectively. The rate of hematoma formation did not differ between the two protocols., Conclusions: This recently introduced, "extended" way of performing VABB in microcalcifications safely minimizes the underestimation rate, which may lead to a modified management of ADH lesions.
- Published
- 2008
- Full Text
- View/download PDF
49. Evaluation of pain experienced during breast ductal endoscopy.
- Author
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Zografos GC, Zagouri F, Sergentanis TN, Gounaris A, Pararas N, Oikonomou V, Panopoulou E, Fotiadis C, and Bramis J
- Subjects
- Adult, Aged, Anesthesia, Local, Exudates and Transudates, Female, Humans, Middle Aged, Nipples, Statistics, Nonparametric, Breast Diseases diagnosis, Endoscopy methods, Pain Measurement methods
- Abstract
Purpose: Ductal endoscopy is valuable for the differential diagnosis of bloody nipple discharge; however, the pain associated with this procedure has not been evaluated. This study aims to assess the pain experienced by patients during ductal endoscopy., Methods: We studied a consecutive series of women who underwent ductal endoscopy, to investigate the cause of bloody nipple discharge. The procedure was performed using standard local anesthesia (lidocaine 1% 10 ml without epinephrine, involving nipple block and periaureolar administration). Patients were asked to score the level of pain with a visual analog scale, 1, 4, 7, 12, 17, 22, 27, and 32 min after the procedure, and describe their overall and maximum pain., Results: This series comprised 20 women aged from 27 to 68 years old. The overall pain (mean +/- SE) score was equal to 5.8 +/-0.3, and the maximum pain score was 8.3 +/- 0.2. The peak of pain corresponded with when the dilator was inserted through the sphincter. The group in which the dilator was inserted after 4 min experienced more intense maximum and overall pain after 7, 12, 17 and 22 min., Conclusions: Pain is an important factor in ductal endoscopy, and peaks relatively early. A standard, baseline local lidocaine dose of greater than 10 ml may be necessary at the beginning of the procedure. Late insertion of the dilator seems to be an indicator of the force of the procedure.
- Published
- 2008
- Full Text
- View/download PDF
50. Vacuum-assisted breast biopsy: the value and limitations of cores with microcalcifications.
- Author
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Zagouri F, Sergentanis TN, Nonni A, Koulocheri D, Fotou M, Panopoulou E, Panou M, Fotiadis C, Bramis J, and Zografos GC
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Middle Aged, Precancerous Conditions pathology, Precancerous Conditions surgery, Retrospective Studies, Vacuum, Biopsy methods, Breast Neoplasms pathology, Breast Neoplasms surgery, Calcinosis pathology, Calcinosis surgery
- Abstract
The aim of this study was to assess cores with microcalcifications (CM) and without microcalcifications (CWM) obtained from vacuum-assisted breast biopsy (VABB). The study included 12 atypical ductal hyperplasias (ADH), 37 ductal carcinomas in situ (DCIS), and seven invasive ductal carcinomas (IDC) diagnosed by VABB (11G) on the Fischer's table. More than 24 cores were excised. For CM/CWM, a separate pathology report was given. Open surgery followed, and underestimation was calculated. The CM/CWM discrepancy was evaluated (superiority, identity, and inferiority). CWM failed to make the diagnosis in 8.3% and 35.1% of ADH and DCIS, respectively. In 28.6% of IDC, diagnosis was made through CWM. CM volume was 1.2+/-0.3 cm(3) for the two IDCs missed by CM, 1.0+/-0.4 cm(3) for the 40 cases of identical diagnoses, and 1.4+/-0.5 cm(3) for the 14 cases of CM superiority (p=0.048, Kruskal-Wallis test). CWM volume was 6.3+/-1.8 cm(3) for the two IDCs missed by CM, 2.6+/-1.8 cm(3) for cases with identical diagnoses, and 3.4+/-1.6 cm(3) for cases of CM superiority (p=0.018, Kruskal-Wallis test). The underestimation rate was 8.3% in ADH, and 10.8% in DCIS. CMs are superior in DCIS/ADH diagnosis. However, CWM may be valuable for the diagnosis of the invasive component.
- Published
- 2007
- Full Text
- View/download PDF
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