George Kouklakis - Academia.edu (original) (raw)

Papers by George Kouklakis

Research paper thumbnail of Endoscopic removal of a toothpick perforating the sigmoid colon and causing chronic abdominal pain: a case report

Research paper thumbnail of Data from Phase I/II Trial of Bevacizumab and Radiotherapy for Locally Advanced Inoperable Colorectal Cancer: Vasculature-Independent Radiosensitizing Effect of Bevacizumab

Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in ... more Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models, and bevacizumab has therapeutic activity in patients with metastatic colorectal cancer.Experimental Design: Twenty-two patients with locally advanced inoperable colorectal carcinomas (LA/I-CRC) were treated with conformal hypofractionated (3.4 Gy/fraction 15) split-course accelerated radiotherapy (biological equivalent dose, 67.2 Gy) supported with amifostine, capecitabine (600 mg/m2 daily, 5 days/week), and bevacizumab (5 mg/kg every 2 weeks, five cycles). Biopsies from nine patients, performed before and 1 week after bevacizumab administration, were analyzed for changes in mRNA expression with Illumina gene arrays.Results: No serious grade 3 chemotherapy-related side effects were recorded. There was low acute toxicity, with moist perineal desquamation noted in 2 of 22 patients, diarrhea grade 2 to 3 in 5 of 22 patients, and severe proctalgia in 2 of 22 patients. On...

Research paper thumbnail of Author ' s response to reviews Title : Spontaneous idiopathic pneumoperitoneum presenting as acute abdomen : a case report

Case Presentation Should read "Emergency laparotomy..." Change made as indicated by the... more Case Presentation Should read "Emergency laparotomy..." Change made as indicated by the reviewer. Emergency laparotomy was performed but no identifiable cause was found. INTRODUCTION This is a very under-referenced section of the manuscript. Almost each line contains a factual statement that is not referenced. Please reference all statement correctly. Change made as indicated by the reviewer. Pneumoperitoneum (PP) is the result of a gastrointestinal (GI) tract perforation in over 90% of cases [1]. Perforation of the stomach or duodenum due to peptic ulcer is considered the most common cause of PP. Pneumoperitoneum can also be the result of a diverticular rupture or of an abdominal trauma [1]. It commonly presents with signs and symptoms of peritonitis, while subphrenic free gas in an upright chest x-ray is the most common radiological finding. Pneumoperitoneum in most cases requires urgent surgical exploration and

Research paper thumbnail of Bevacizumab-based conformal radio-chemotherapy for locally advanced inoperable colorectal cancer

Journal of Clinical Oncology, 2008

Research paper thumbnail of Association between Helicobacter pylori burden and Alzheimer's disease

European journal of neurology : the official journal of the European Federation of Neurological Societies, 2014

Keywords: Alzheimer's disease; bacterial infections; cognitive disorders and dementia; infect... more Keywords: Alzheimer's disease; bacterial infections; cognitive disorders and dementia; infections; mild cognitive impairment; neurological disorders

Research paper thumbnail of Benign post-radiation rectal stricture treated with endoscopic balloon dilation and intralesional triamcinolone injection

Case reports in gastroenterology, 2012

Post-radiation stricture is a rare complication after pelvis irradiation, but must be in the mind... more Post-radiation stricture is a rare complication after pelvis irradiation, but must be in the mind of the clinician evaluating a lower gastrointestinal obstruction. Endoscopy has gained an important role in chronic radiation proctitis with several therapeutic options for management of intestinal strictures. The treatment of rectal strictures has been limited to surgery with high morbidity and mortality. Therefore, a less invasive therapeutic approach for benign rectal strictures, endoscopic balloon dilation with or without intralesional steroid injection, has become a common treatment modality. We present a case of benign post-radiation rectal stricture treated successfully with balloon dilation and adjuvant intralesional triamcinolone injection. A 70-year-old woman presented to the emergency room complaining for 2 weeks of diarrhea and meteorism, 11 years after radiation of the pelvis due to adenocarcinoma of the uterus. Colonoscopy revealed a stricture at the rectum and multiple en...

Research paper thumbnail of Locoregional immunochemotherapy in hepatocellular carcinoma

Hepato-gastroenterology

Hepatocellular carcinoma remains a disease with a poor and dismal prognosis, and all forms of cur... more Hepatocellular carcinoma remains a disease with a poor and dismal prognosis, and all forms of currently available conventional therapies are rarely beneficial. However, in recent years, combined targeting locoregional immunochemotherapy has been reported with very promising results. Adoptive immunotherapy with LAK cells (lymphokine-activated killer cells) and recombinant interleukin-2 is becoming one of the new modalities to reconstitute the depressed immune status of the tumor-bearing host. Interleukin-2, gamma-interferon, and interleukin-12 induce cytolytic activity of LAK and natural killer cells and are considered for cellular activation to locoregional immunotherapy before, after resection or even in unresectable hepatocellular carcinomas. Spleen is a suitable organ for LAK cell induction because it has densely packed lymphocytes. The strategy of administration of both interleukin-2 and gamma-interferon into the spleen for in vivo immunostimulation is based on the well-known sy...

Research paper thumbnail of Does Prophylactic Administration of Somatostatin Decrease the Rates of Complications After Pancreatic Resection?

Pancreas, 2013

The postoperative morbidity after pancreatectomy remains high. The role of somatostatin and its a... more The postoperative morbidity after pancreatectomy remains high. The role of somatostatin and its analogs in reducing complications after pancreatic resection is controversial. The aim of the study was to evaluate the ability of somatostatin to influence pancreatic cell's function with consequence the decrease of postoperative complications. Between January 2006 and December 2009, 67 patients for which pancreatectomy was indicated were randomized into 2 groups. At surgery, biopsies of the pancreas were taken to be studied by electron microscopy and analyzed for ultrastructural morphometry. The total mortality was 4.4% (n = 3/67; 2 patients from the control group and 1 patient from the treatment group). The overall morbidity was 35.8% (n = 24/67). Eighteen patients in the control group (n = 18/32; 56.25%) and 6 patients in the treatment group (n = 6/35; 17.14%) developed postoperative complications (2-tailed Fisher exact test; P = 0.001). The most common complication was the presence of fistula (n = 6/67; 8.95%). Perioperative administration of intravenous somatostatin at rates applied in this study was able to inhibit the exocrine pancreatic function. This finding supports the prophylactic effect of somatostatin on the early postoperative complications of pancreatic surgery shown in this study.

Research paper thumbnail of Enterolith Small-Bowel Obstruction Caused by Jejunal Diverticulosis: Report of a Case

Research paper thumbnail of Bevacizumab, Capecitabine, Amifostine, and Preoperative Hypofractionated Accelerated Radiotherapy (HypoArc) for Rectal Cancer: A Phase II Study

International Journal of Radiation Oncology*Biology*Physics, 2011

Bevacizumab has established therapeutic activity in patients with metastatic colorectal cancer, a... more Bevacizumab has established therapeutic activity in patients with metastatic colorectal cancer, and anti-vascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models. We assessed the feasibility and efficacy of preoperative radiochemotherapy combined with bevacizumab in patients with rectal cancer. Nineteen patients with radiologic T3 and/or N+ rectal carcinoma were treated with preoperative conformal hypofractionated accelerated radiotherapy (3.4 Gy in 10 consecutive fractions) supported with amifostine (500-1,000 mg daily), capecitabine (600 mg/m(2) twice daily, 5 days per week), and bevacizumab (5 mg/kg every 2 weeks for 2 cycles). Surgery followed 6 weeks after the end of radiotherapy. A cohort of 14 sequential patients treated with the same regimen without bevacizumab was available for comparison. Grade 2 or 3 diarrhea was noted in 7 of 19 patients (36.8%), which was statistically worse than patients receiving the same regimen without bevacizumab (p = 0.01). A higher incidence of Grade 2 or 3 proctalgia was also noted (21.1%) (p = 0.03). Bladder and skin toxicity was negligible. All toxicities regressed completely within 2 weeks after the end of therapy. Pathologic complete and partial response was noted in 7 of 19 cases (36.8%) and 8 of 19 cases (42.1%). Within a median follow-up of 21 months, none of the patients has had late complications develop and only 1 of 18 evaluable cases (5.5%) has had locoregional relapse. Bevacizumab can be safely combined with hypofractionated radiotherapy and capecitabine as a preoperative radiochemotherapy regimen for patients with rectal cancer. The high pathologic complete response rates urges the testing of bevacizumab in randomized studies.

Research paper thumbnail of Primary umbilical endometrioma: a rare case of spontaneous abdominal wall endometriosis

International Journal of General Medicine, 2012

Research paper thumbnail of Helicobacter pylori induced cognitive dysfunction might be associated with falls and fractures in cirrhosis

Research paper thumbnail of Helicobacter pylori Infection Might Contribute to Esophageal Adenocarcinoma Progress in Subpopulations With Gastroesophageal Reflux Disease and Barrett's Esophagus

Helicobacter, 2012

To the Editor, Fischbach et al. [1] concluded that estimates for the effect of Helicobacter pylor... more To the Editor, Fischbach et al. [1] concluded that estimates for the effect of Helicobacter pylori (H. pylori) on Barrett’s esophagus (BE) were heterogenous across studies; although overall H. pylori, and particularly cagA cytotoxin, tended to be protective for BE in most studies, H. pylori effect on BE varied by geographic location. Barrett’s esophagus is a complication of long-standing gastroesophageal reflux disease (GERD) and wellrecognized premalignant condition playing a pivotal role in the development of esophageal adenocarcinoma (EA), the most common esophageal malignancy in Western countries with increasing faster incidence than any other cancer [2]; GERD plays a crucial role in the pathophysiology and the clinical identification of BE [2]. In this regard, our data show that H. pylori infection (H. pylori-I) is frequent in Greek patients with GERD and even with nonendoscopical reflux disease [2], and H. pylori eradication leads to better control of GERD symptoms and improves esophagitis [2,3]. Moreover, consistent associations with the Greek data were shown by others [3] also reporting improvement in reflux symptoms following H. pylori treatment. It is important to note that some other authors, usually prior supporters of the theory that H. pylori “protects” against GERD, relented their initial findings, claiming that H. pylori eradication does not cause or protect against GERD and, moreover, recommending H. pylori eradication in GERD [4]. Additionally, although epidemiologic studies do not suggest causality with H. pylori, however, such studies support our and others’ findings; for instance, a large study (~21,000 cases) showed that the decrease in H. pylori-I parallels the decrease in peptic ulcer prevalence, and the increase in GERD and reappearance of GERD after H. pylori eradication is rare. Moreover, contrary to expectation, patients hospitalized with duodenal ulcers (61,548 cases), obviously attributed to H. pylori-I, had a significant 70% excess risk of EA. Much evidence further potentiates the concern that H. pylori is not “protective” against GERD [5] and its complications including BE and EA. The interplay between H. pylori and host factors plays an important role in the pathogenesis of GERD. Specifically, H. pylori may contribute to GERD pathogenesis by several mechanisms including release of several mediators, cytokines, and nitric oxide, which may adversely affect the lower esophageal sphincter (LES); direct damage of the esophageal mucosa by bacterial products; increased production of prostaglandins that sensitize afferent nerves and reduce LES pressure; and augmented acidity (by gastrin release) that exacerbate GERD [3]. The authors considered some putative pathways involving H. pylori and a decreased risk of BE [1]. However, these pathways might represent the one BE pathogenic “coin’s” side. Regarding the other alternative side, gastrin, induced by H. pylori-I, is an oncogenic growth factor contributing to esophageal, gastric, and colon carcinogenesis and, in particular, playing a potential causal effect on neoplastic progression in BE; gastrin stimulates proliferation via JAK2and Akt-dependent NF-kappaB (NF-jB) activation in Barrett’s EA cells, shows antiapoptotic activity through upregulation of Bcl-2 and survivin, and upregulates cyclooxygenase (COX)-2 expression [2]. In this regard, H. pylori-I activates NF-jB, an oxidantsensitive transcription regulator of inducible expression of inflammatory genes such as COX-2, which regulates gastrointestinal cancer cell growth and proliferation. In particular, H. pylori-I induced NF-jB and COX-2 expression in esophageal epithelial cells, playing a role in inflammation associated with BE and tumorigenesis in the esophagus [2]; upon colonizing esophagus, H. pylori increases the severity of esophageal inflammation and the incidence of BE and EA [6]. Moreover, recent evidence indicates that 1, H. pylori-I prevalence is high in BE; 2, neither H. pylori-I nor H. pylori-I by CagA+ strains reduce the risk of BE in certain populations with high prevalence of H. pylori-I; 3, the expected incidence of EA with persistent H. pylori-I is higher than that of EA after eradication of infection [5]; H. pylori-I may affect specific molecular alterations (genetic instability, E-cadherin methylation, and monoclonal antibody Das-1) associated with the pathogenesis of BE; and 4, H. pylori induces

Research paper thumbnail of Relationship between Helicobacter pylori infection and autoimmune disorders

Clinical Chemistry and Laboratory Medicine, 2013

* Corresponding author: Jannis Kountouras , MD, PhD, Professor of Medicine, Department of Gastroe... more * Corresponding author: Jannis Kountouras , MD, PhD, Professor of Medicine, Department of Gastroenterology, Second Medical Clinic, Aristotle University of Thessaloniki, Ippokration Hospital, 8 Fanariou St, Byzantio, 551 33 Thessaloniki, Greece, Phone: + 3

Research paper thumbnail of Phase I/II Trial of Bevacizumab and Radiotherapy for Locally Advanced Inoperable Colorectal Cancer: Vasculature-Independent Radiosensitizing Effect of Bevacizumab

Clinical Cancer Research, 2009

Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in ... more Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models, and bevacizumab has therapeutic activity in patients with metastatic colorectal cancer. Experimental Design: Twenty-two patients with locally advanced inoperable colorectal carcinomas (LA/I-CRC) were treated with conformal hypofractionated (3.4 Gy/fraction 15) split-course accelerated radiotherapy (biological equivalent dose, 67.2 Gy) supported with amifostine, capecitabine (600 mg/m2 daily, 5 days/week), and bevacizumab (5 mg/kg every 2 weeks, five cycles). Biopsies from nine patients, performed before and 1 week after bevacizumab administration, were analyzed for changes in mRNA expression with Illumina gene arrays. Results: No serious grade 3 chemotherapy-related side effects were recorded. There was low acute toxicity, with moist perineal desquamation noted in 2 of 22 patients, diarrhea grade 2 to 3 in 5 of 22 patients, and severe proctalgia in 2 of 22 patients. ...

Research paper thumbnail of Laparoscopic resection of a pancreatic serous cystadenoma preserving the integrity of main pancreatic duct: a case report

Research paper thumbnail of Spontaneous bowel perforation complicating ventriculoperitoneal shunt: a case report

Research paper thumbnail of Re: Helicobacter Pylori Infection and Colorectal Cancer Risk: Evidence From a Large Population-Based Case-Control Study in Germany

American Journal of Epidemiology, 2012

Research paper thumbnail of Early Antivascular Effects of Bevacizumab Anti-VEGF Monoclonal Antibody on Colorectal Carcinomas Assessed With Functional CT Imaging

American Journal of Clinical Oncology, 2007

Research paper thumbnail of Tuberculosis in the Peritoneum: Not Too Rare After All

Case Reports in Gastroenterology, 2012

Research paper thumbnail of Endoscopic removal of a toothpick perforating the sigmoid colon and causing chronic abdominal pain: a case report

Research paper thumbnail of Data from Phase I/II Trial of Bevacizumab and Radiotherapy for Locally Advanced Inoperable Colorectal Cancer: Vasculature-Independent Radiosensitizing Effect of Bevacizumab

Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in ... more Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models, and bevacizumab has therapeutic activity in patients with metastatic colorectal cancer.Experimental Design: Twenty-two patients with locally advanced inoperable colorectal carcinomas (LA/I-CRC) were treated with conformal hypofractionated (3.4 Gy/fraction 15) split-course accelerated radiotherapy (biological equivalent dose, 67.2 Gy) supported with amifostine, capecitabine (600 mg/m2 daily, 5 days/week), and bevacizumab (5 mg/kg every 2 weeks, five cycles). Biopsies from nine patients, performed before and 1 week after bevacizumab administration, were analyzed for changes in mRNA expression with Illumina gene arrays.Results: No serious grade 3 chemotherapy-related side effects were recorded. There was low acute toxicity, with moist perineal desquamation noted in 2 of 22 patients, diarrhea grade 2 to 3 in 5 of 22 patients, and severe proctalgia in 2 of 22 patients. On...

Research paper thumbnail of Author ' s response to reviews Title : Spontaneous idiopathic pneumoperitoneum presenting as acute abdomen : a case report

Case Presentation Should read "Emergency laparotomy..." Change made as indicated by the... more Case Presentation Should read "Emergency laparotomy..." Change made as indicated by the reviewer. Emergency laparotomy was performed but no identifiable cause was found. INTRODUCTION This is a very under-referenced section of the manuscript. Almost each line contains a factual statement that is not referenced. Please reference all statement correctly. Change made as indicated by the reviewer. Pneumoperitoneum (PP) is the result of a gastrointestinal (GI) tract perforation in over 90% of cases [1]. Perforation of the stomach or duodenum due to peptic ulcer is considered the most common cause of PP. Pneumoperitoneum can also be the result of a diverticular rupture or of an abdominal trauma [1]. It commonly presents with signs and symptoms of peritonitis, while subphrenic free gas in an upright chest x-ray is the most common radiological finding. Pneumoperitoneum in most cases requires urgent surgical exploration and

Research paper thumbnail of Bevacizumab-based conformal radio-chemotherapy for locally advanced inoperable colorectal cancer

Journal of Clinical Oncology, 2008

Research paper thumbnail of Association between Helicobacter pylori burden and Alzheimer's disease

European journal of neurology : the official journal of the European Federation of Neurological Societies, 2014

Keywords: Alzheimer's disease; bacterial infections; cognitive disorders and dementia; infect... more Keywords: Alzheimer's disease; bacterial infections; cognitive disorders and dementia; infections; mild cognitive impairment; neurological disorders

Research paper thumbnail of Benign post-radiation rectal stricture treated with endoscopic balloon dilation and intralesional triamcinolone injection

Case reports in gastroenterology, 2012

Post-radiation stricture is a rare complication after pelvis irradiation, but must be in the mind... more Post-radiation stricture is a rare complication after pelvis irradiation, but must be in the mind of the clinician evaluating a lower gastrointestinal obstruction. Endoscopy has gained an important role in chronic radiation proctitis with several therapeutic options for management of intestinal strictures. The treatment of rectal strictures has been limited to surgery with high morbidity and mortality. Therefore, a less invasive therapeutic approach for benign rectal strictures, endoscopic balloon dilation with or without intralesional steroid injection, has become a common treatment modality. We present a case of benign post-radiation rectal stricture treated successfully with balloon dilation and adjuvant intralesional triamcinolone injection. A 70-year-old woman presented to the emergency room complaining for 2 weeks of diarrhea and meteorism, 11 years after radiation of the pelvis due to adenocarcinoma of the uterus. Colonoscopy revealed a stricture at the rectum and multiple en...

Research paper thumbnail of Locoregional immunochemotherapy in hepatocellular carcinoma

Hepato-gastroenterology

Hepatocellular carcinoma remains a disease with a poor and dismal prognosis, and all forms of cur... more Hepatocellular carcinoma remains a disease with a poor and dismal prognosis, and all forms of currently available conventional therapies are rarely beneficial. However, in recent years, combined targeting locoregional immunochemotherapy has been reported with very promising results. Adoptive immunotherapy with LAK cells (lymphokine-activated killer cells) and recombinant interleukin-2 is becoming one of the new modalities to reconstitute the depressed immune status of the tumor-bearing host. Interleukin-2, gamma-interferon, and interleukin-12 induce cytolytic activity of LAK and natural killer cells and are considered for cellular activation to locoregional immunotherapy before, after resection or even in unresectable hepatocellular carcinomas. Spleen is a suitable organ for LAK cell induction because it has densely packed lymphocytes. The strategy of administration of both interleukin-2 and gamma-interferon into the spleen for in vivo immunostimulation is based on the well-known sy...

Research paper thumbnail of Does Prophylactic Administration of Somatostatin Decrease the Rates of Complications After Pancreatic Resection?

Pancreas, 2013

The postoperative morbidity after pancreatectomy remains high. The role of somatostatin and its a... more The postoperative morbidity after pancreatectomy remains high. The role of somatostatin and its analogs in reducing complications after pancreatic resection is controversial. The aim of the study was to evaluate the ability of somatostatin to influence pancreatic cell's function with consequence the decrease of postoperative complications. Between January 2006 and December 2009, 67 patients for which pancreatectomy was indicated were randomized into 2 groups. At surgery, biopsies of the pancreas were taken to be studied by electron microscopy and analyzed for ultrastructural morphometry. The total mortality was 4.4% (n = 3/67; 2 patients from the control group and 1 patient from the treatment group). The overall morbidity was 35.8% (n = 24/67). Eighteen patients in the control group (n = 18/32; 56.25%) and 6 patients in the treatment group (n = 6/35; 17.14%) developed postoperative complications (2-tailed Fisher exact test; P = 0.001). The most common complication was the presence of fistula (n = 6/67; 8.95%). Perioperative administration of intravenous somatostatin at rates applied in this study was able to inhibit the exocrine pancreatic function. This finding supports the prophylactic effect of somatostatin on the early postoperative complications of pancreatic surgery shown in this study.

Research paper thumbnail of Enterolith Small-Bowel Obstruction Caused by Jejunal Diverticulosis: Report of a Case

Research paper thumbnail of Bevacizumab, Capecitabine, Amifostine, and Preoperative Hypofractionated Accelerated Radiotherapy (HypoArc) for Rectal Cancer: A Phase II Study

International Journal of Radiation Oncology*Biology*Physics, 2011

Bevacizumab has established therapeutic activity in patients with metastatic colorectal cancer, a... more Bevacizumab has established therapeutic activity in patients with metastatic colorectal cancer, and anti-vascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models. We assessed the feasibility and efficacy of preoperative radiochemotherapy combined with bevacizumab in patients with rectal cancer. Nineteen patients with radiologic T3 and/or N+ rectal carcinoma were treated with preoperative conformal hypofractionated accelerated radiotherapy (3.4 Gy in 10 consecutive fractions) supported with amifostine (500-1,000 mg daily), capecitabine (600 mg/m(2) twice daily, 5 days per week), and bevacizumab (5 mg/kg every 2 weeks for 2 cycles). Surgery followed 6 weeks after the end of radiotherapy. A cohort of 14 sequential patients treated with the same regimen without bevacizumab was available for comparison. Grade 2 or 3 diarrhea was noted in 7 of 19 patients (36.8%), which was statistically worse than patients receiving the same regimen without bevacizumab (p = 0.01). A higher incidence of Grade 2 or 3 proctalgia was also noted (21.1%) (p = 0.03). Bladder and skin toxicity was negligible. All toxicities regressed completely within 2 weeks after the end of therapy. Pathologic complete and partial response was noted in 7 of 19 cases (36.8%) and 8 of 19 cases (42.1%). Within a median follow-up of 21 months, none of the patients has had late complications develop and only 1 of 18 evaluable cases (5.5%) has had locoregional relapse. Bevacizumab can be safely combined with hypofractionated radiotherapy and capecitabine as a preoperative radiochemotherapy regimen for patients with rectal cancer. The high pathologic complete response rates urges the testing of bevacizumab in randomized studies.

Research paper thumbnail of Primary umbilical endometrioma: a rare case of spontaneous abdominal wall endometriosis

International Journal of General Medicine, 2012

Research paper thumbnail of Helicobacter pylori induced cognitive dysfunction might be associated with falls and fractures in cirrhosis

Research paper thumbnail of Helicobacter pylori Infection Might Contribute to Esophageal Adenocarcinoma Progress in Subpopulations With Gastroesophageal Reflux Disease and Barrett's Esophagus

Helicobacter, 2012

To the Editor, Fischbach et al. [1] concluded that estimates for the effect of Helicobacter pylor... more To the Editor, Fischbach et al. [1] concluded that estimates for the effect of Helicobacter pylori (H. pylori) on Barrett’s esophagus (BE) were heterogenous across studies; although overall H. pylori, and particularly cagA cytotoxin, tended to be protective for BE in most studies, H. pylori effect on BE varied by geographic location. Barrett’s esophagus is a complication of long-standing gastroesophageal reflux disease (GERD) and wellrecognized premalignant condition playing a pivotal role in the development of esophageal adenocarcinoma (EA), the most common esophageal malignancy in Western countries with increasing faster incidence than any other cancer [2]; GERD plays a crucial role in the pathophysiology and the clinical identification of BE [2]. In this regard, our data show that H. pylori infection (H. pylori-I) is frequent in Greek patients with GERD and even with nonendoscopical reflux disease [2], and H. pylori eradication leads to better control of GERD symptoms and improves esophagitis [2,3]. Moreover, consistent associations with the Greek data were shown by others [3] also reporting improvement in reflux symptoms following H. pylori treatment. It is important to note that some other authors, usually prior supporters of the theory that H. pylori “protects” against GERD, relented their initial findings, claiming that H. pylori eradication does not cause or protect against GERD and, moreover, recommending H. pylori eradication in GERD [4]. Additionally, although epidemiologic studies do not suggest causality with H. pylori, however, such studies support our and others’ findings; for instance, a large study (~21,000 cases) showed that the decrease in H. pylori-I parallels the decrease in peptic ulcer prevalence, and the increase in GERD and reappearance of GERD after H. pylori eradication is rare. Moreover, contrary to expectation, patients hospitalized with duodenal ulcers (61,548 cases), obviously attributed to H. pylori-I, had a significant 70% excess risk of EA. Much evidence further potentiates the concern that H. pylori is not “protective” against GERD [5] and its complications including BE and EA. The interplay between H. pylori and host factors plays an important role in the pathogenesis of GERD. Specifically, H. pylori may contribute to GERD pathogenesis by several mechanisms including release of several mediators, cytokines, and nitric oxide, which may adversely affect the lower esophageal sphincter (LES); direct damage of the esophageal mucosa by bacterial products; increased production of prostaglandins that sensitize afferent nerves and reduce LES pressure; and augmented acidity (by gastrin release) that exacerbate GERD [3]. The authors considered some putative pathways involving H. pylori and a decreased risk of BE [1]. However, these pathways might represent the one BE pathogenic “coin’s” side. Regarding the other alternative side, gastrin, induced by H. pylori-I, is an oncogenic growth factor contributing to esophageal, gastric, and colon carcinogenesis and, in particular, playing a potential causal effect on neoplastic progression in BE; gastrin stimulates proliferation via JAK2and Akt-dependent NF-kappaB (NF-jB) activation in Barrett’s EA cells, shows antiapoptotic activity through upregulation of Bcl-2 and survivin, and upregulates cyclooxygenase (COX)-2 expression [2]. In this regard, H. pylori-I activates NF-jB, an oxidantsensitive transcription regulator of inducible expression of inflammatory genes such as COX-2, which regulates gastrointestinal cancer cell growth and proliferation. In particular, H. pylori-I induced NF-jB and COX-2 expression in esophageal epithelial cells, playing a role in inflammation associated with BE and tumorigenesis in the esophagus [2]; upon colonizing esophagus, H. pylori increases the severity of esophageal inflammation and the incidence of BE and EA [6]. Moreover, recent evidence indicates that 1, H. pylori-I prevalence is high in BE; 2, neither H. pylori-I nor H. pylori-I by CagA+ strains reduce the risk of BE in certain populations with high prevalence of H. pylori-I; 3, the expected incidence of EA with persistent H. pylori-I is higher than that of EA after eradication of infection [5]; H. pylori-I may affect specific molecular alterations (genetic instability, E-cadherin methylation, and monoclonal antibody Das-1) associated with the pathogenesis of BE; and 4, H. pylori induces

Research paper thumbnail of Relationship between Helicobacter pylori infection and autoimmune disorders

Clinical Chemistry and Laboratory Medicine, 2013

* Corresponding author: Jannis Kountouras , MD, PhD, Professor of Medicine, Department of Gastroe... more * Corresponding author: Jannis Kountouras , MD, PhD, Professor of Medicine, Department of Gastroenterology, Second Medical Clinic, Aristotle University of Thessaloniki, Ippokration Hospital, 8 Fanariou St, Byzantio, 551 33 Thessaloniki, Greece, Phone: + 3

Research paper thumbnail of Phase I/II Trial of Bevacizumab and Radiotherapy for Locally Advanced Inoperable Colorectal Cancer: Vasculature-Independent Radiosensitizing Effect of Bevacizumab

Clinical Cancer Research, 2009

Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in ... more Purpose: Antivascular endothelial growth factor therapy enhances the activity of radiotherapy in experimental models, and bevacizumab has therapeutic activity in patients with metastatic colorectal cancer. Experimental Design: Twenty-two patients with locally advanced inoperable colorectal carcinomas (LA/I-CRC) were treated with conformal hypofractionated (3.4 Gy/fraction 15) split-course accelerated radiotherapy (biological equivalent dose, 67.2 Gy) supported with amifostine, capecitabine (600 mg/m2 daily, 5 days/week), and bevacizumab (5 mg/kg every 2 weeks, five cycles). Biopsies from nine patients, performed before and 1 week after bevacizumab administration, were analyzed for changes in mRNA expression with Illumina gene arrays. Results: No serious grade 3 chemotherapy-related side effects were recorded. There was low acute toxicity, with moist perineal desquamation noted in 2 of 22 patients, diarrhea grade 2 to 3 in 5 of 22 patients, and severe proctalgia in 2 of 22 patients. ...

Research paper thumbnail of Laparoscopic resection of a pancreatic serous cystadenoma preserving the integrity of main pancreatic duct: a case report

Research paper thumbnail of Spontaneous bowel perforation complicating ventriculoperitoneal shunt: a case report

Research paper thumbnail of Re: Helicobacter Pylori Infection and Colorectal Cancer Risk: Evidence From a Large Population-Based Case-Control Study in Germany

American Journal of Epidemiology, 2012

Research paper thumbnail of Early Antivascular Effects of Bevacizumab Anti-VEGF Monoclonal Antibody on Colorectal Carcinomas Assessed With Functional CT Imaging

American Journal of Clinical Oncology, 2007

Research paper thumbnail of Tuberculosis in the Peritoneum: Not Too Rare After All

Case Reports in Gastroenterology, 2012