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Dive into the research topics where Alexandros Giakoustidis is active.

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Featured researches published by Alexandros Giakoustidis.


Free Radical Research | 2006

Attenuation of intestinal ischemia/reperfusion induced liver and lung injury by intraperitoneal administration of (−)-Epigallocatechin-3-gallate

Alexandros Giakoustidis; Dimitrios Giakoustidis; Stavros Iliadis; Georgios Papageorgiou; Kokona Koliakou; Nicholas Kontos; Ioannis Taitzoglou; E. Botsoglou; Vasilis Papanikolaou; Kostas Atmatzidis; Dimitrios Takoudas; Antonios Antoniadis

The aim of this study was to evaluate the effect of ( − )-epigallocatechin-3-gallate (EGCG), a natural antioxidant, on liver and lungs after warm intestinal ischemia/reperfusion (I/R). Thirty male Wistar rats were equally divided into a sham-operation group, an intestinal I/R group and an intestinal I/R group pretreated with EGCG intraperitoneally. Intestinal ischemia was induced by occlusion of the superior mesenteric artery for 60 min followed by reperfusion for 120 min. Immediately after reperfusion, liver, lung and blood samples were collected and analyzed. Results showed that intestinal I/R increased the levels of aspartate (AST) and alanine (ALT) transaminase in serum to 987 and 752 IU/l, respectively. Malondialdehyde (MDA) increased in liver to 1.524 nmol/g in the group subjected to intestinal I/R compared to 0.995 nmol/g in the sham operation group. MDA was also increased in lungs to 1.581 nmol/g compared to 0.896 nmol/g in the sham operation group. Myeloperoxidase (MPO) increased in liver, after intestinal I/R, to 5.16 U/g compared to 1.59 U/g in the sham operation group. MPO was also increased in lungs to 3.89 U/g compared to 1.65 U/g in the sham operation group. Pretreatment with EGCG decreased serum levels of AST and ALT to 236 and 178 IU/l, respectively. It also decreased mean MDA levels in liver and lungs to 1.061 and 1.008 nmol/g, respectively, and mean MPO levels in liver and lungs to 1.88 and 1.71 U/g, respectively. Light microscopy and transmission electron microscopy examinations showed significant alteration in liver and lungs and protection of liver and lung parenchyma in the animals treated with EGCG.


Journal of Surgical Research | 2010

Attenuation of Liver Ischemia/Reperfusion Induced Apoptosis by Epigallocatechin-3-Gallate Via Down-Regulation of NF-κB and c-Jun Expression

Dimitrios Giakoustidis; Alexandros Giakoustidis; Stavros Iliadis; Kokona Koliakou; Nikolaos Antoniadis; Nikolaos Kontos; Georgios Papageorgiou; Eleni Kaldrimidou; Dimitrios Takoudas

INTRODUCTION Hepatic ischemia/reperfusion (I/R) activates Kupffer cells and initiates severe oxidative stress with enhanced production of reactive oxygen species (ROS) and tumor necrosis factor-alpha (TNF-alpha). ROS and TNF-alpha mediate the expression of nuclear factors and kinases, activating the signal transduction pathway, and triggering apoptosis. The aim of our study was to evaluate the potential protective effect of (-)-epigallocatechin-3-gallate (EGCG) administration in inhibition of apoptosis by attenuating the expression of NF-kappaB, c-Jun, and caspase-3 in a model of severe hepatic I/R. MATERIALS AND METHODS Thirty Wistar rats were allocated into three groups. Sham operation, I/R, and I/R-EGCG 50mg/kg. Hepatic ischemia was induced for 60min by Pringles maneuver. Malondialdehyde (MDA), myeloperoxidase (MPO), light histology, scanning electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and immunocytochemistry for NF-kappaB, c-Jun, caspase-3, analysis on liver specimens and aspartate (AST), and alanine (ALT) transferases analysis in serum, were performed 120min after reperfusion. RESULTS Apoptosis as indicated by TUNEL and caspase-3 was widely expressed in the I/R group but very limited in the EGCG treated group. Liver was stained positive for NF-kappaB and c-Jun in the I/R group but failed to be stained positive in the EGCG treated group. MDA, MPO, AST, and ALT showed marked increase in the I/R group and significant decrease in EGCG treated group. Significant alterations of liver specimens were observed by light histology and transmission electron microscopy whilst pretreatment with EGCG resulted in parenchymal preservation. CONCLUSIONS Administration of EGCG is likely to inhibit I/R-induced apoptosis and protect liver by down-regulating NF-kappaB and c-Jun signal transduction pathways.


Surgery Today | 2006

The Protective Effect of α-Tocopherol and GdCl3 Against Hepatic Ischemia/Reperfusion Injury

Dimitrios Giakoustidis; George Papageorgiou; Stavros Iliadis; Alexandros Giakoustidis; Evanthia Kostopoulou; Nickolas Kontos; E. Botsoglou; Dimitrios Tsantilas; Dimitrios Takoudas

PurposeTo evaluate the combined effect of α-tocopherol and gadolinium chloride (GdCl3) in reducing lipid peroxidation after severe hepatic ischemia/reperfusion (IR) injury.MethodsSixty male Wistar rats, 200–250 g, were randomly divided into six equal groups. There were two sham operation (SHAM) groups, two untreated IR groups, and two IR groups treated with GdCl3 and α-tocopherol (IRGT). After 60 min of total hepatic ischemia and 120 min reperfusion, one of each group was killed, liver samples were taken for malondialdehyde (MDA) and myeloperoxidase (MPO) analysis and light microscopy examination, and blood samples were analyzed for aspartate (AST) and alanine (ALT) transaminase, lactate dehydrogenase (LDH), and α-tocopherol content. The remaining groups were monitored for survival rate determination.ResultsThe mean MDA and MPO values in the SHAM, IR, and IRGT groups, respectively, were 1.117, 1.476, and 0.978 nmol/g wet tissue and 1.49, 6.26, and 1.78 (U/g). The mean α-tocopherol values in the SHAM, IR, and IRGT groups, respectively, were 10.4, 1.9, and 12 µmol/l. The mean serum AST, ALT, and LDH values were significantly higher in the IR group than in the SHAM group (P < 0.001), and significantly lower in the IRGT group than in the IR group (P < 0.001). Light microscopy examination revealed more severe congestion and vacuolization in the IR group than in the SHAM group, and minimal congestion and vacuolization in the IRGT group. Survival was significantly higher in the IRGT group than in the IR group.ConclusionThe administration of GdCl3 and α-tocopherol is likely to protect the liver against lipid peroxidation by suppressing Kupffer cell and polymorphonuclear leukocyte activation and enhancing endogenous antioxidant activity.


Free Radical Research | 2008

Inhibition of intestinal ischemia/repurfusion induced apoptosis and necrosis via down-regulation of the NF-kB, c-Jun and caspace-3 expression by epigallocatechin-3-gallate administration

Alexandros Giakoustidis; Dimitrios Giakoustidis; Kokona Koliakou; Eleni Kaldrymidou; Stavros Iliadis; Nickolaos Antoniadis; Nicholas Kontos; Georgios Papageorgiou; Konstantinos Atmatzidis; Dimitrios Takoudas

Intestinal ischemia/reperfusion (I/R) produces reactive oxygen species (ROS) activating signal transduction and apoptosis. The aim of this study was to evaluate the effect of (−)-epigallocatechin-3-gallate (EGCG) administration in inhibition of apoptosis by attenuating the expression of NF-kB, c-Jun and caspace-3 in intestinal I/R. Thirty male wistar rats were used. Group A sham operation, B I/R, C I/R-EGCG 50 mg/kg ip. Intestinal ischemia was induced for 60 min by clamping the superior mesenteric artery. Malondialdehyde (MDA), myeloperoxidase (MPO), light histology, Fragment End Labelling of DNA (TUNEL), immunocytochemistry for NF-kB, c-Jun and caspace-3 analysis in intestinal specimens were performed 120 min after reperfusion. Apoptosis as indicated by TUNEL and Caspace-3, NF-kB and c-Jun was widely expressed in I/R group but only slightly expressed in EGCG treated groups. MDA and MPO showed a marked increase in the I/R group and a significant decrease in the EGCG treated group. Light histology showed preservation of architecture in the EGCG treated group. In conclusion, EGCG pre-treatment is likely to inhibit intestinal I/R-induced apoptosis by down-regulating the expression of NF-kB, c-Jun and caspase-3.


Canadian Journal of Gastroenterology & Hepatology | 2015

Molecular signalling in hepatocellular carcinoma: Role of and crosstalk among WNT/ß-catenin, Sonic Hedgehog, Notch and Dickkopf-1.

Alexandros Giakoustidis; Dimitrios Giakoustidis; Satvinder Mudan; Argyrios Sklavos; Roger Williams

Hepatocellular carcinoma is the sixth most common cancer worldwide. In the majority of cases, there is evidence of existing chronic liver disease from a variety of causes including viral hepatitis B and C, alcoholic liver disease and nonalcoholic steatohepatitis. Identification of the signalling pathways used by hepatocellular carcinoma cells to proliferate, invade or metastasize is of paramount importance in the discovery and implementation of successfully targeted therapies. Activation of Wnt/β-catenin, Notch and Hedgehog pathways play a critical role in regulating liver cell proliferation during development and in controlling crucial functions of the adult liver in the initiation and progression of human cancers. β-catenin was identified as a protein interacting with the cell adhesion molecule E-cadherin at the cell-cell junction, and has been shown to be one of the most important mediators of the Wnt signalling pathway in tumourigenesis. Investigations into the role of Dikkopf-1 in hepatocellular carcinoma have demonstrated controversial results, with a decreased expression of Dickkopf-1 and soluble frizzled-related protein in various cancers on one hand, and as a possible negative prognostic indicator of hepatocellular carcinoma on the other. In the present review, the authors focus on the Wnt⁄β-catenin, Notch and Sonic Hedgehog pathways, and their interaction with Dikkopf-1 in hepatocellular carcinoma.


Transplantation Proceedings | 2008

Impact of double-j ureteric stent in kidney transplantation: single-center experience.

Dimitrios Giakoustidis; K. Diplaris; Nikolaos Antoniadis; A. Papagianis; N. Ouzounidis; I. Fouzas; D. Vrochides; D. Kardasis; Georgios Tsoulfas; Alexandros Giakoustidis; G. Miserlis; G. Imvrios; Dimitrios Takoudas

We retrospectively evaluated the use of double-j stent and the incidence of urological complications in 2 groups of patients who received a kidney transplant. From January 2005 to September 2007 we studied 172 patients receiving kidney transplants, 65 and 107 from living and cadaver donors, respectively. From the 172 patients, a total of 34 were excluded due to ureterostomy or Politano-Leadbetter ureterovesical anastomosis. Another 21 patients were excluded from the study due to graft loss due to acute or hyperacute rejection, cytomegalovirus (CMV) infection, or vascular complication. The remaining patients were divided into 2 groups: group A (44 patients) and B (73 patients) with versus without the use of a double-j-stent, respectively. The 2 groups were comparable in terms of donor and recipient gender, ischemia time, and delayed graft function. We failed to observes significant differences between the 2 groups in mean hospital stay (23 +/- 9 and 19 +/- 9), urinary leak (2.3% and 4.1%), and urinary tract infection (20.4% and 19.2%), among groups A and B, respectively. The only difference observed concerned the gravity of the urinary leak; no surgical intervention was needed among the double-j stent group versus 2 patients demanding ureterovesical reconstruction in the nonstent group. In conclusion, our data suggested that the routine use of a double-j stent for ureterovesical anastomosis neither significantly increased urinary tract infection rates, nor decreased the incidence of urinary leaks, but may decrease the gravity of the latter as evidenced by the need for surgical intervention.


Journal of Surgical Oncology | 2015

Neutrophil to lymphocyte ratio predicts pattern of recurrence in patients undergoing liver resection for colorectal liver metastasis and thus the overall survival.

Alexandros Giakoustidis; Kyriakos Neofytou; Aamir Z. Khan; Satvinder Mudan

We investigate the neutrophil to lymphocyte ratio (NLR) as a potential prognostic factor for patients undergoing curative liver resection for colorectal liver metastasis (CRLM).


Transplantation proceedings | 2012

Prevalence and clinical impact of cytomegalovirus infection and disease in renal transplantation: ten years of experience in a single center.

Dimitrios Giakoustidis; A. Antoniadis; I. Fouzas; A. Sklavos; Alexandros Giakoustidis; N. Ouzounidis; Dimitrios Gakis; K. Koubanagiti; G. Myserlis; A. Tsitlakidis; I. Gerogiannis; A. Papagiannis; P. Christoforou; T. Deligiannidis; F. Solonaki; G. Imvrios

INTRODUCTION Renal transplantation is regarded as the optimal treatment for patients with end-stage renal disease. Despite significant improvements in surgical techniques and immunosuppressive therapy, long-term graft survival has not markedly increased over the years, due in part to the occurrence of cytomegalovirus (CMV) infection. PATIENTS AND METHODS Between January 2001 and September 2011, we performed 592 kidney transplantations (214 living and 378 cadaveric donors). All patients received induction therapy with interleukin (IL)-2 monoclonal antibodies or antithymoglobulin (ATG) combined with calcineurin inhibitors, mycophenolate mofetil, or mTOR antagonists and steroids. All CMV-seronegative patients and all subjects receiving ATG induction were prescribed prophylactic therapy with ganciclovir-intravenous (IV) for 15 days 2.5 mg/kg BW bid and thereafter oral valgancyclovir once a day. CMV infection was diagnosed using a CMV-PVR of ≥ 600 copies. We analyzed the time to manifestations of CMV infection, or positive CMV-PCR, patient and graft survival, serum creatinine (Cr), and blood urea nitrogen (BUN) values before and after CMV infection, as well as type of immunosuppression therapy. RESULTS The overall incidences of CMV infection and CMV disease were 76/592 (12.8%) and 23/592 (3.9%), respectively. The mean ± standard deviation (SD) times to positive CMV-PCR and CMV disease were 16.66 ± 23.38 months and 106 ± 61.2 (range, 28-215) days, respectively. Mortality was 1% (6/592) among our whole population, 7.9% (6/76) for CMV-infected, and 26% (6/23) in the CMV disease cohort. Cr and BUN showed no significant differences among the groups. CONCLUSIONS CMV infection and CMV disease comprise significant clinical problems, increasing morbidity and mortality. The use of prophylactic anti-CMV treatment is of paramount importance.


Future Oncology | 2010

Clinical utility of circulating tumor cell measurement in the diagnosis of indeterminate lesions of the pancreas

Satvinder Mudan; Alexandros Giakoustidis; Andrew V Thillainayagam; Jimmy Jacob; Justin Stebbing

The quantification of circulating tumor cells has been historically problematic due to the different methods applied to their measurement. Following the development of standardized technology, they are now becoming well-established prognostic and predictive markers in patients with breast, colon and prostate cancer. While they represent a real-time noninvasive test, their use in diagnostics has seldom been reported. We report their use to help diagnose an indeterminate pancreatic mass. The use of an automated circulating tumor cell platform as described is likely to have utility as an aid to differential diagnosis, although larger studies will be required to ascertain its positive or negative predictive value.


Liver Transplantation | 2016

Interleukin 18 binding protein ameliorates ischemia/reperfusion-induced hepatic injury in mice.

N. Ouzounidis; Alexandros Giakoustidis; Theofilos Poutahidis; Katerina Angelopoulou; Stavros Iliadis; Antonis Chatzigiagkos; Argyro Zacharioudaki; Stamatis Angelopoulos; Apostolos Papalois; Dimitrios Giakoustidis

Inflammation‐associated oxidative stress contributes to hepatic ischemia/reperfusion injury (IRI). Detrimental inflammatory event cascades largely depend on activated Kupffer cells (KCs) and neutrophils, as well as proinflammatory cytokines, including tumor necrosis factor α (TNF‐α) and interleukin (IL) 18. The aim of our study was to evaluate the effects of IL 18 binding protein (IL 18Bp) in hepatic IRI of mice. Thirty C57BL/6 mice were allocated into 3 groups: sham operation, ischemia/reperfusion (I/R), and I/R with intravenous administration of IL 18Bp. Hepatic ischemia was induced for 30 minutes by Pringles maneuver. After 120 minutes of reperfusion, mice were euthanized, and the liver and blood samples were collected for histological, immunohistochemical, molecular, and biochemical analyses. I/R injury induced the typical liver pathology and upregulated IL‐18 expression in the liver of mice. Binding of IL 18 with IL 18Bp significantly reduced the histopathological indices of I/R liver injury and KC apoptosis. The I/R‐induced increase of TNF‐α, malondialdehyde, aspartate aminotransferase, and alanine aminotransferase levels was prevented in statistically significant levels because of the pretreatment with IL 18Bp. Likewise, blocking of IL 18 ablated the I/R‐associated elevation of nuclear factor kappa B, c‐Jun, myeloperoxidase, and IL 32 and the up‐regulation of neutrophils and T‐helper lymphocytes. Administration of IL 18Bp protects the mice liver from I/R injury by intervening in critical inflammation‐associated pathways and KC apoptosis. Liver Transpl 22:237‐246, 2016.

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Satvinder Mudan

The Royal Marsden NHS Foundation Trust

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Dimitrios Giakoustidis

Aristotle University of Thessaloniki

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Kyriakos Neofytou

The Royal Marsden NHS Foundation Trust

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Aamir Z. Khan

The Royal Marsden NHS Foundation Trust

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Stavros Iliadis

Aristotle University of Thessaloniki

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Dimitrios Takoudas

Aristotle University of Thessaloniki

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Nikolaos Antoniadis

Aristotle University of Thessaloniki

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David Cunningham

The Royal Marsden NHS Foundation Trust

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Elizabeth C. Smyth

The Royal Marsden NHS Foundation Trust

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Mafalda Costa Neves

The Royal Marsden NHS Foundation Trust

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