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SEVEN, GÜLSEREN

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Author: SEVEN, GÜLSEREN × Type: Article ×

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    Long-term outcomes associated with pancreatic extracorporeal shock wave lithotripsy for chronic calcific pancreatitis
    (2012-05-01T00:00:00Z) Seven, GÜLSEREN; Schreiner, Mitchal A.; Ross, Andrew S.; Lin, Otto S.; Gluck, Michael; Gan, S. Ian; Irani, Shayan; Brandabur, John J.; Patterson, David; Kuhr, Christian; Kozarek, Richard; SEVEN, GÜLSEREN
    Background: Most outcomes data on pancreatic extracorporeal shock wave lithotripsy (P-ESWL) for chronic calcific pancreatitis (CCP) are based on studies with < 4 years- follow-up, and U.S. long-term studies are lacking.
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    Partially versus fully covered self-expanding metal stents for benign and malignant esophageal conditions: a single center experience
    (2013-06-01T00:00:00Z) Seven, GÜLSEREN; Irani, Shayan; Ross, Andrew S.; Gan, S. Ian; Gluck, Michael; Low, Donald; Kozarek, Richard A.; SEVEN, GÜLSEREN
    Fully covered self-expanding metal stents (FCSEMS), unlike partially covered SEMS (PCSEMS), have been used to treat benign as well as malignant conditions. We aimed to evaluate the outcome of PCSEMS and FCSEMS in patients with both benign and malignant esophageal diseases.
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    Assessment of Helicobacter pylori eradication rate of triple combination therapy containing levofloxacin
    (2011-12-01T00:00:00Z) Seven, GÜLSEREN; Cinar, Kubilay; Yakut, Mustafa; Idilman, Ramazan; Ozden, Ali; SEVEN, GÜLSEREN
    Background/aims: Owing to its high efficacy, ease of use, perfect adaptation and low complication profile, it is suggested that the triple therapy combination consisting of levofloxacin, amoxicillin and proton pump inhibitor may be an alternative for the first-line and second-line treatment of Helicobacter pylori. The aim of this study is to evaluate the efficacy of the triple therapy regimen containing two different doses of levofloxacin in the first-line eradication treatment. Material and Methods: 110 naive patients with anti Helicobacter pylori treatment indications according to Maastricht III Consensus Report were included to the study. Patients were randomized into two groups as the patients treated with a levofloxacin (500 mg o.i.d), amoxicillin (1 g b.i.d) and proton pump inhibitor (b.i.d) combination for 10 days (Group 1, n=60) and patients treated with a levofloxacin (500 mg b.i.d), amoxicillin (1 g bid) and proton pump inhibitor (b.i.d) combination for 10 days (Group 2, n=50). Eradication rate was assessed at the 6th week of therapy just subsequent to termination of treatment. Results: 110 treatment-naive patients (60 female, mean age: 44.1 +/- 14.7 years) were randomized and all patients completed the study. Helicobacter pylori eradication of the Group I was 60% and in Group 2 was 72.7%. The difference between the two groups was not statistically significant (p=0.427). None of patients experienced severe complication that would lead to discontinuation of therapy. Conclusion: It is observed that the efficacy of the triple therapy combination containing levofloxacin is not within acceptable limits for the first-line Helicobacter pylori eradication.
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    PublicationOpen Access
    Differentiating Gastrointestinal Stromal Tumors from Leiomyomas Using a Neural Network Trained on Endoscopic Ultrasonography Images.
    (2021-10-07T00:00:00Z) Seven, GÜLSEREN; Silahtaroglu, Gokhan; Seven, Ozden Ozluk; Senturk, Hakan; SEVEN, GÜLSEREN
    Background: Endoscopic ultrasonography (EUS) is crucial to diagnose and evaluate gastrointestinal mesenchymal tumors (GIMTs). However, EUS-guided biopsy does not always differentiate gastrointestinal stromal tumors (GISTs) from leiomyomas. We evaluated the ability of a convolutional neural network (CNN) to differentiate GISTs from leiomyomas using EUS images. The conventional EUS features of GISTs were also compared with leiomyomas. Patients and methods: Patients who underwent EUS for evaluation of upper GIMTs between 2010 and 2020 were retrospectively reviewed, and 145 patients (73 women and 72 men; mean age 54.8 ± 13.5 years) with GISTs (n = 109) or leiomyomas (n = 36), confirmed by immunohistochemistry, were included. A total of 978 images collected from 100 patients were used to train and test the CNN system, and 384 images from 45 patients were used for validation. EUS images were also evaluated by an EUS expert for comparison with the CNN system. Results: The sensitivity, specificity, and accuracy of the CNN system for diagnosis of GIST were 92.0%, 64.3%, and 86.98% for the validation dataset, respectively. In contrast, the sensitivity, specificity, and accuracy of the EUS expert interpretations were 60.5%, 74.3%, and 63.0%, respectively. Concerning EUS features, only higher echogenicity was an independent and significant factor for differentiating GISTs from leiomyomas (p < 0.05). Conclusions: The CNN system could diagnose GIMTs with higher accuracy than an EUS expert and could be helpful in differentiating GISTs from leiomyomas. A higher echogenicity may also aid in differentiation.
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    Double Balloon Enteroscopy in a North American Setting: A Large Single Center 5-year Experience
    (2013-01-01T00:00:00Z) Seven, Gülseren; SEVEN, GÜLSEREN
    Background/Aims: Double balloon enteroscopy (DBE) allows both diagnosis and therapeutic maneuvers in the small bowel. Its use was pioneered in Europe and Asia but there remains a relative paucity of literature from North America. Our aim in this study was to determine diagnostic and therapeutic yield in a North American setting. Methods: A five-year retrospective analy-sis of all patients undergoing DBE at a single tertiary care North American hospital was performed. Results: Four-hundred fifty-seven procedures, 265 anterograde and 192 retrograde, were performed on 335 patients. The most common indications were obscure gastrointestinal bleeding, small bowel obstruction, and suspected masses and mucosal abnormalities. Total en-teroscopy was achieved in 19 of the 89 patients who had both anterograde and retrograde procedures. Overall diagnostic yield in the determination of cause of symptoms or previous imaging was 52%. The most common causes of obscure bleeding were small bowel ulcers (10%), vascular lesions (25%) and neoplasms (10%). The most common causes of small bowel obstruction were strictures, some of which underwent dilation. Other therapeutic interventions included polypectomy, retrieval of retained capsules, stent retrievals and percutaneous enteral jejunostomy tube placement. Overall complication rates were very low (0.6%) and included medication reaction (n=1), scope dysfunction (n=1) and perforation (n=1). Conclusions: DBE can be per-formed safely and with good diagnostic yield in a single referral center in North America. (Intest Res 2013;11:34-40Background/Aims: Double balloon enteroscopy (DBE) allows both diagnosis and therapeutic maneuvers in the small bowel. Its use was pioneered in Europe and Asia but there remains a relative paucity of literature from North America. Our aim in this study was to determine diagnostic and therapeutic yield in a North American setting. Methods: A five-year retrospective analy-sis of all patients undergoing DBE at a single tertiary care North American hospital was performed. Results: Four-hundred fifty-seven procedures, 265 anterograde and 192 retrograde, were performed on 335 patients. The most common indications were obscure gastrointestinal bleeding, small bowel obstruction, and suspected masses and mucosal abnormalities. Total en-teroscopy was achieved in 19 of the 89 patients who had both anterograde and retrograde procedures. Overall diagnostic yield in the determination of cause of symptoms or previous imaging was 52%. The most common causes of obscure bleeding were small bowel ulcers (10%), vascular lesions (25%) and neoplasms (10%). The most common causes of small bowel obstruction were strictures, some of which underwent dilation. Other therapeutic interventions included polypectomy, retrieval of retained capsules, stent retrievals and percutaneous enteral jejunostomy tube placement. Overall complication rates were very low (0.6%) and included medication reaction (n=1), scope dysfunction (n=1) and perforation (n=1). Conclusions: DBE can be per-formed safely and with good diagnostic yield in a single referral center in North America. (Intest Res 2013;11:34-40Background/Aims: Double balloon enteroscopy (DBE) allows both diagnosis and therapeutic maneuvers in the small bowel. Its use was pioneered in Europe and Asia but there remains a relative paucity of literature from North America. Our aim in this study was to determine diagnostic and therapeutic yield in a North American setting. Methods: A five-year retrospective analy-sis of all patients undergoing DBE at a single tertiary care North American hospital was performed. Results: Four-hundred fifty-seven procedures, 265 anterograde and 192 retrograde, were performed on 335 patients. The most common indications were obscure gastrointestinal bleeding, small bowel obstruction, and suspected masses and mucosal abnormalities. Total en-teroscopy was achieved in 19 of the 89 patients who had both anterograde and retrograde procedures. Overall diagnostic yield in the determination of cause of symptoms or previous imaging was 52%. The most common causes of obscure bleeding were small bowel ulcers (10%), vascular lesions (25%) and neoplasms (10%). The most common causes of small bowel obstruction were strictures, some of which underwent dilation. Other therapeutic interventions included polypectomy, retrieval of retained capsules, stent retrievals and percutaneous enteral jejunostomy tube placement. Overall complication rates were very low (0.6%) and included medication reaction (n=1), scope dysfunction (n=1) and perforation (n=1). Conclusions: DBE can be per-formed safely and with good diagnostic yield in a single referral center in North America. (Intest Res 2013;11:34-40
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    Use of anti tumor necrosis factor-alpha monoclonal antibody for ulcerative jejunoileitis
    (2012-09-01T00:00:00Z) Seven, GÜLSEREN; Assaad, Adel; Biehl, Thomas; Kozarek, Richard A.; SEVEN, GÜLSEREN
    Ulcerative jejunoileitis is an uncommon clinical syndrome consisting of abdominal pain, weight loss associated with diarrhea, and multiple inflammatory ulcerations and strictures of the small bowel. Ulcerative jejunoileitis can complicate established celiac disease or develop in patients de novo. Increased levels of tumor necrosis factor-alpha (TNF-alpha) in the small intestine of patients with untreated celiac disease are associated with a role in the immune pathogenesis of this disorder. No specific therapy has been shown to change the course of ulcerative jejunoileitis. We report a case of severe ulcerative jejunoileitis previously unresponsive to traditional therapies, including high dose corticosteroids and cyclosporine. The patient had a dramatic resolution of symptoms and a complete normalization of endoscopic findings after anti-TNF-alpha monoclonal antibody, infliximab (Remicade (R)). (c) 2012 Baishideng. All rights reserved.
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    Effects of tissue cytomegalovirus quantitative polymerase chain reaction in the management of ulcerative colitis flare-ups: Should we wave aside?
    (2021-12-03T00:00:00Z) Kochan, Koray; Seven, Gulseren; Bas, Suleyman; Kiremitci, Sercan; Gecer, Melin; Senturk, Hakan; BİBERCİ KESKİN, ELMAS; SEVEN, GÜLSEREN
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    Entecavir Treatment of Chronic Hepatitis D
    (2012-09-01T00:00:00Z) Kabacam, Gokhan; ÖNDER, Fatih Oğuz; Yakut, Mustafa; Seven, GÜLSEREN; Karatayli, Senem C.; Karatayli, Ersin; Savas, Berna; Idilman, Ramazan; Bozdayi, A. Mithat; Yurdaydin, Cihan; SEVEN, GÜLSEREN
    Background. Hepatitis D virus (HDV) requires hepatitis B surface antigen (HBsAg) to propagate infection and cause disease. Entecavir is a nucleoside analog with potent antiviral efficacy, and in the woodchuck animal model it also decreased hepatitis B virus (HBV) cccDNA and woodchuck surface antigen. The aim of this study was to investigate the efficacy of entecavir in chronic hepatitis D (CHD).
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    Evaluation of Ki67 index in endoscopic ultrasound-guided fine needle aspiration samples for the assessment of malignancy risk in gastric gastrointestinal stromal tumors.
    (2020-10-05T00:00:00Z) Senturk, Hakan; Seven, GÜLSEREN; Kochan, KORAY; Caglar, Erkan; Kiremitci, Sercan; Koker, Ibrahim Hakki; SEVEN, GÜLSEREN; KOÇHAN, KORAY; KÖKER, İBRAHİM HAKKI; ŞENTÜRK, HAKAN
    Background: The risk of malignancy in resected gastrointestinal stromal tumors (GISTs) depends on tumor size, location, and mitotic index. Reportedly, the Ki67 index has a prognostic value in resected GISTs. We aimed to analyze the accuracy of endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) samples with reference to Ki67 index, using surgical specimens as the gold standard. Methods: Fifty-five patients who underwent EUS-FNA followed by surgical resection for gastric GISTs were retrospectively analyzed. Patients’ age and sex; tumors’ size and location; mitotic index, cell type, cellularity, pleomorphism, presence of ulceration, hemorrhage, necrosis, mucosal or serosal invasion, growth pattern, and Ki67 index based on pathology were investigated. Results: Location in fundus, ulceration, hemorrhage, mucosal invasion, and Ki67 index in surgical specimens were significant in predicting high-risk groups (P < 0.05) on univariate analysis. resence of bleeding (P = 0.034) and the Ki67 index (P = 0.018) were the only independent significant factors in multivariate analysis. The optimal cutoff level of Ki67 was 5%, with 88.2% sensitivity and 52.8% specificity (P = 0.021). The mean Ki67 index was lower in EUS-FNA samples than in surgical specimens [2% (1-15) vs. 10% (1-70), P = 0.001]. The rank correlation coefficient value of Ki67 was 0.199 (P = 0.362) between EUS-FNA and surgical samples and showed no reliability for EUS-FNA samples. Conclusion: The Ki67 index in resected specimens correlated with high-risk GISTs, although it had no additive value to the current criteria. The Ki67 index in EUS-guided FNA samples is not a reliable marker of proliferation in GISTs.
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    PublicationOpen Access
    Predictive Role of Acute Phase Reactants in the Response to Therapy in Patients with Chronic Hepatitis C Virus Infection
    (2013-01-01T00:00:00Z) Oguz, Ayten; Atay, Ahmet Engin; Tas, Adnan; Seven, GÜLSEREN; Koruk, Mehmet; SEVEN, GÜLSEREN
    Background/Aims: Biochemical parameters and acute-phase proteins (APPs) may provide complementary data in patients with chronic hepatitis C (CHC). We aimed to evaluate the predictive role of APPs in the response to antiviral therapy. Methods: Forty-five patients underwent antiviral therapy. Serum ferritin, C-reactive protein (CRP), transferrin, albumin, alpha-1 acid glycoprotein (A1AG), and alpha-2 macroglobulin (A2MG) levels were examined at the initial evaluation and at the 4th, 12th, and 48th weeks. HCV RNA levels were examined at the initial evaluation and at the 12th and 48th weeks. Results: Ferritin, transferrin, A1AG, and A2MG levels were significantly higher in the patient group (p<0.05). CRP, ferritin, A1AG, and A2MG levels were significantly increased from baseline to the 4th week (p<0.05). The responders and nonresponders to antiviral therapy had insignificantly but remarkably different levels of CRP, ferritin, transferrin, A1AG, A2MG, and alanine aminotransferase (ALT) both at the initial evaluation and at the 12th week. Conclusions: Variations in ferritin, A1AG, A2MG, albumin, CRP, and transferrin levels are not alternatives to virological and biochemical parameters for predicting an early response to therapy in patients with CHC. However, the investigation of ALT levels and hepatitis C virus RNA in combination with acute-phase reactants may provide supplementary data for evaluating responses to antiviral therapy. (Gut Liver 2013;7:82-88)