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Dive into the research topics where Alkiviadis Kostakis is active.

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Featured researches published by Alkiviadis Kostakis.


International Journal of Colorectal Disease | 2009

Survivin -31G/C promoter polymorphism and sporadic colorectal cancer

Maria Gazouli; Nikolaos Tzanakis; George Rallis; George Theodoropoulos; Ioannis Papaconstantinou; Alkiviadis Kostakis; Nicholas P. Anagnou; Nikolaos Nikiteas

IntroductionSurvivin is an apoptotic inhibitor, plays an important role in cell cycle regulation, and may be involved in the development and progression of cancer. A common polymorphism at the survivin gene promoter (-31 G/C) has been shown to influence survivin expression and the risk for cancer.AimThe aim of the present study was to investigate whether this polymorphism could be involved in the sporadic colorectal cancer (CRC) development, prognosis, and survival.Materials and methodsThe -31G/C polymorphism of survivin promoter was analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism method in biopsies from 312 patients with sporadic CRC and 362 healthy individuals. Survivin messenger RNA (mRNA) expression in CRC tissues was detected by quantitative reverse transcriptase PCR.Results and discussionThe genotype frequencies for -31GG, -31GC, and -31CC were 21.79%, 41.99%, and 36.22% in CRC patients and 33.98%, 45.03%, and 20.99% in healthy subjects, respectively. The frequencies of the survivin -31C allele and CC genotype were significantly higher in CRC patients than in healthy subjects (p < 0.0001). Homozygotes for the -31CC survivin genotype, expressed 1.6-fold higher mRNA levels of survivin compared to cases with the -31GG and -31GC genotypes.ConclusionThe -31CC genotype of survivin promoter is associated with CRC and may be a risk factor for CRC.


Acta Radiologica | 2004

Breast arterial calcifications as an indicator of systemic vascular disease

Christos Markopoulos; Dimitrios Mantas; K. Revenas; E. Kouskos; A. Tzonou; C. Liapis; Alkiviadis Kostakis

Purpose: To evaluate the association between mammographically detected arterial calcifications and systemic vascular disease. Material and Methods: The medical records of 77 women who had either breast arterial calcifications or underwent surgery for carotid stenosis, abdominal aortic aneurysm, or femoropopliteal bypass (study groups A and B) were evaluated and compared with 33 women without breast arterial calcifications (group C). Patients in both arms of the study underwent additional vascular tests or mammography. Results: Currently available data indicate that there is a statistically significant correlation between the presence of arterial calcifications on the mammogram and atheromatosis of the carotid or femoral arteries. Conclusion: Screening mammograms might be useful in the detection of women at risk for systemic vascular disease.


Urologia Internationalis | 2007

De novo Renal Cell Carcinoma in a Kidney Allograft 13 Years after Transplantation: A Case Report and Review of the Literature

George Zavos; John D. Kakisis; John Bokos; Paris Pappas; John Boletis; Alkiviadis Kostakis

De novo carcinoma of the renal transplant is a rare but disastrous clinical entity. We report such a tumor developing 13 years after transplantation and describe its clinical presentation, diagnostic approach and therapy. The importance of a surveillance program allowing early detection of tumor developing in the renal transplant is emphasized.


European Journal of Gastroenterology & Hepatology | 2015

Chronic severe constipation: current pathophysiological aspects, new diagnostic approaches, and therapeutic options.

Nikolaos Andromanakos; Stamatis I. Pinis; Alkiviadis Kostakis

Chronic constipation is a considerable problem because it significantly affects the quality of a patient’s life. Constipation can be diagnosed at every age and is more frequent in women and among the elderly. In epidemiological studies, its incidence is estimated at 2–27% in the general population. Chronic constipation may be primary or secondary. However, primary constipation (functional or idiopathic) can be classified into normal transit constipation, slow transit constipation, and pelvic outlet obstruction. In this review we make an attempt to present the current pathophysiological aspects and new therapeutic options for chronic idiopathic constipation, particularly highlighting the value of patient assessment for accurate diagnosis of the cause of the problem, thus helping in the choice of appropriate treatment.


World Journal of Surgery | 2003

Surgery for inguinal hernia in Byzantine times (A.D. 324-1453): first scientific descriptions.

John Lascaratos; Constantine Tsiamis; Alkiviadis Kostakis

The aim of this article is to present the techniques applied by Byzantine physicians for inguinal hernia repair and to note their influence on the development of surgery after that time. A study and analysis of the original texts of the Byzantine medical writers, written in Greek, and containing the now mostly lost knowledge of the ancient Hellenistic and Roman periods, was undertaken. Two Byzantine physicians, Aetius of Amida (6th century A.D.) and Paul of Aegina (7th century A.D.), described two techniques for confrontation of inguinal hernia, namely the surgical removal of the prolapsed peritoneum and the cauterization of the groin. These methods were probably derived from the texts of earlier Greek surgeons to which they added their own keen observations. The study of Byzantine medical and literary texts proves that the surgical techniques for inguinal hernia were practiced in Byzantine times and influenced later Arabian and European surgery, thus constituting significant roots of surgery.


Acta Haematologica | 2014

UGT1A1*28 Polymorphism in Chronic Lymphocytic Leukemia: The First Investigation of the Polymorphism in Disease Susceptibility and Its Specific Cytogenetic Abnormalities

Maria Karakosta; Vassiliki Kalotychou; Alkiviadis Kostakis; Gabriel E. Pantelias; Ioannis Rombos; Gregory Kouraklis; Kalliopi N. Manola

Chronic lymphocytic leukemia (CLL) has been recently attributed to a combination of genetic predisposition and exposure to environmental factors. UDP-glucuronosyltransferase (UGT)1A1*28 is an inborn polymorphism that results in significant downregulation of uridine diphosphate glucuronyltransferase 1-1 (UGT1A1) activity, one of the most critical metabolizing enzymes involved in the detoxification of toxic substances, some of which contribute to CLL pathogenesis. Here, for the first time, we investigated the putative impact of UGT1A1*28 on CLL incidence and on the formation of the most common chromosomal abnormalities of CLL. UGT1A1*28 was investigated in 109 CLL patients and 108 healthy controls, and was associated with karyotypic and fluorescence in situ hybridization (FISH) results. A significant high frequency of the mutant genotype was observed in patients carrying abnormal FISH patterns, especially del(11q) and +12, which are CLL-specific abnormalities. We also observed a significant association between UGT1A1*28 and the intermediate to unfavorable cytogenetic CLL risk groups. No difference, though, was observed in genotypes between patients and controls. Therefore, we could suggest that UGT-deficient individuals may be at a greater risk for developing CLL-specific abnormalities. Our study might serve as a starting point to consider UGT1A1*28 polymorphism as one of the possible predisposing factors of CLL pathogenesis.


Langenbeck's Archives of Surgery | 2007

The role of liquid-based cytology in the investigation of colorectal lesions: a cytohistopathological correlation and evaluation of diagnostic accuracy

Konstantinos Kontzoglou; Konstantinos G. Moulakakis; Dimitrios Alexiou; Michael Safioleas; Nikolaos Nikiteas; Anna-Eva Giahnaki; Aspasia Kyroudes; Alkiviadis Kostakis; Petros Karakitsos

Background and aimsThe role of cytologic techniques is not widely accepted even if it is well documented that the cytologic investigation of colorectal tract could complement the biopsy and increase the correct diagnosis of carcinomas. This study aims to evaluate the role of Thin-Prep® liquid-based cytology in the investigation of colorectal lesions.Materials and methodsWe compared the diagnostic accuracy of Thin-Prep® with that of biopsy in 158 patients with signs and symptoms of the lower gastrointestinal tract. Each patient underwent colonoscopy, followed by tissue biopsy and brush cytology. Brushing material was obtained and prepared according to the operating manual of Thin-Prep®.ResultsThe rate of unsatisfactory smears was 5% (8/158) with liquid-based technique and appeared to be slightly higher than the respective of biopsy [3.2% (5/158) (5 vs 3.2%, P = 0.18)]. Based on the final diagnosis, 89 out of 93 total malignant cases and 53 out of 53 total benign cases were correctly diagnosed with Thin-Prep® technique (four false negatives). Accurate diagnosis with biopsy was performed in 87 out of 93 total malignant cases and 53 out of 53 total benign cases with biopsy (six false negatives). Neither in Thin-Prep® technique nor in biopsy were false-positive cases observed. The sensitivities of detecting malignancy by Thin-Prep® and biopsy were 95.7, and 93.5%, respectively (no significant difference, P = 0.239). The sensitivity was augmented (98.9%) when the two techniques were combined, and this difference was found to be statistically significant (98.9 vs 92.9, P = 0.01, and 98.9 vs 95.7, P = 0.039).ConclusionsLiquid-based cytology appears to be an easy, highly accurate, and reliable cytologic method for the diagnostic approach of colorectal diseases and could be applied as complementary to biopsy for the improvement of the diagnosis. Moreover, could be used for DNA ploidy analysis and immmunohistochemical studies.


Clinical Transplantation | 2013

Impact of donor and recipient age difference on long-term allograft survival after living donor renal transplantation: analysis of 478 cases

Ioannis D. Kostakis; Demetrios Moris; Alexandros Barlas; Ioannis Bokos; Maria N. Darema; Eleni Theodoropoulou; Georgios Karaolanis; Alkiviadis Kostakis; Ioannis Boletis; Georgios Zavos

Either deceased or living‐related renal transplantation constitutes the best therapeutic option for patients with end‐stage renal disease. In this retrospective study, an attempt to identify parameters that affect allograft survival in living donor renal transplantation was made.


Journal of Vascular Research | 2017

Overexpression of Toll-Like Receptors 2, 3, 4, and 8 Is Correlated to the Vascular Atherosclerotic Process in the Hyperlipidemic Rabbit Model: The Effect of Statin Treatment

Alkistis Kapelouzou; Stavros Giaglis; Michalis Peroulis; Michalis Katsimpoulas; Petros Moustardas; Chrysostomos V. Arvanitis; Alkiviadis Kostakis; Panagiotis Karayannakos; Dennis V. Cokkinos

Background: Atherosclerosis is the major cause of cardiovascular disease; hypercholesterolemia is a major risk factor. We hypothesized that specific TLR members (TLR2, TLR3, TLR4, TLR8) may play a role in atherosclerosis progression and its accompanying inflammatory response. We determined the association of atherosclerotic lesions and TLR mRNA expression in different aortic sites. We also assessed the effects of fluvastatin (Flu) treatment on TLR expression and plaque characteristics. Methods: Male rabbits, fed with an atherogenic diet for a duration of 3 months, were screened for advanced atherosclerotic lesions in the aorta. Additional animals received normal diet or normal diet plus Flu for 1 additional month. TLR mRNA expression in various thoracic and abdominal aortic segments was assessed, together with atherosclerotic changes. Results: After high lipid diet, the atherosclerotic burden increased more in the abdominal than in the thoracic aorta; TLR2, 3, 4, and 8 also increased significantly. Flu decreased atherosclerotic plaque, calcium deposition, lipid cores, intraplaque hemorrhage, erythrocyte membranes, endothelial cells, and macrophage infiltration, while increasing smooth muscle cells in plaques of both aortic segments; it also lowered TLR2, 3, 4, and 8 expression in all aortic segments to a stronger degree than resumption of normal diet. There was a strong association between blood and tissue parameters during experimental period and finally a strong correlation found between these parameters with mRNA of TLR2, 3, 4, and 8 in various stages. Conclusion: For the first time TLR2, 3, 4, and 8 mRNA expression is prospectively explored after hypercholesterolemic diet in the rabbit model. TLR2, 3, 4, and 8 mRNA expression is strongly upregulated and correlates with the progression of atherosclerosis in the aorta. Flu significantly inhibited this progress and reduced inflammation via TLR downregulation which was strongly associated with regression of plaque morphology and atherosclerosis promoting factors.


Annals of Plastic Surgery | 2006

Soft-tissue sarcomas and reconstruction options: twenty-two years of experience.

Othon Papadopoulos; Petros Konofaos; Chrisostomos Chrisostomidis; Elina Papadimitraki; A. Stratigos; Alkiviadis Kostakis

Soft tissue sarcomas (STS) are particularly rare malignancies that constitute less than 1% of all malignancies. In recent years, prognostic clinical factors have been defined that help to stratify patients regarding their risk for local and distant recurrence and death from disease. Tumor grade, size, depth, completeness of resection, and presentation status are among the independent prognostic factors. At present, the treatment of these tumors constitutes a wide or marginal excision, adequate primary reconstruction, and radiotherapy. Surgery has generally been recommended as the primary method of treatment for achieving local control. Modern reconstructive surgery, especially musculocutaneous, either pedicle or free flaps, has made more extensive resections possible, while providing acceptable cosmetic and functional results. This study deals with our experience in the treatment of resectable STS with selective combination of treatment modalities.

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Despina Perrea

National and Kapodistrian University of Athens

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Nikolaos Nikiteas

National and Kapodistrian University of Athens

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Othon Papadopoulos

National and Kapodistrian University of Athens

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Dimitrios Filippou

National and Kapodistrian University of Athens

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John Boletis

National and Kapodistrian University of Athens

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Maria Gazouli

National and Kapodistrian University of Athens

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Petros Konofaos

National and Kapodistrian University of Athens

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