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Publications (13)15.86 Total impact

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    Clinics 09/2008; 63(4):561-4. DOI:10.1590/S1807-59322008000400027 · 1.42 Impact Factor
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    ABSTRACT: Sildenafil both enhances vasodilatation by relaxing the smooth muscle in the vessels and inhibits platelet aggregation. We have therefore examined the potential benefits of sildenafil on an animal model for ischemic colitis (IC). Twenty-eight female Wistar albino rats weighing 250-300 g were randomized into three experimental groups as follows: in Group 1, animals were sham operated (n = 8) and received tap water; in Groups 2 and 3, the rats underwent a standardized surgical procedure to induce IC (n = 10 in each group). Group 2 animals served as the controls, receiving only tap water, while Group 3 animals received 10 mg/kg sildenafil per day as a single dose for a 3-day period. All animals were sacrificed 72 h after devascularization. To determine the severity of the ischemia, we scored the macroscopically visible damage, measured the ischemic area and scored the histopathology. Tissue malondialdehyde levels were also evaluated. The mean area of ischemic changes were 116.80 +/- 189.93 and 0.55 +/- 1.01 mm2 in Group 2 and 3 animals, respectively (p = 0.0001), while the macroscopically mean visible damage score decreased to 0.66 +/- 0.70 (p = 0.0001) for Group 3 animals. The Chiu scores were 0.00, 3.80 +/- 0.91 and 2.66 +/- 1.00 in Group 1, 2 and 3 animals, respectively. There was a statistically significant difference between Group 2 and 3 animals (p = 0.017). Our findings support the view that sildenafil leads to a improvement in IC due to its well-known effects on the vascular smooth muscle and on the microcirculatory hemodynamics.
    Digestive Diseases and Sciences 07/2008; 53(6):1618-23. DOI:10.1007/s10620-007-0033-9 · 2.55 Impact Factor
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    ABSTRACT: Surgeon inexperience has been defined as a significant predictor of deleterious outcome in thyroid surgery; however, the safety of training programs in which residents are the primary surgeons is controversial. The objective of this prospective study was to compare the complication rates of total thyroidectomy (TT) performed by residents with those of TT performed by specialist surgeons in similar patient groups. Between April 2001 and May 2007, 144 patients underwent TT at our hospital. For 75 operations, the primary surgeon was a resident under the direct supervision of the attending surgeon, and for 69 operations, the primary surgeon was the experienced attending surgeon. Pre-and postoperative vocal cord examinations and serum calcium level evaluations were carried out in all patients. The rates of temporary (unilateral) recurrent laryngeal nerve (RLN) palsy were 2.66% vs 2.17% after TT performed by the residents vs the attending surgeon, respectively. There were no significant differences in the incidences of temporary hypoparathyroidism (20% vs 20.28%), permanent (unilateral) RLN palsy, hematoma, infection, seroma, and incidental parathyroidectomy between the two groups. The complication rates of TT performed by residents and attending surgeons were similar. Thus, residents can perform TT safely and effectively under the direct supervision of a senior surgeon. Ultimately, strict adherence to the contemporary principles of thyroid surgery is of paramount importance.
    Surgery Today 02/2008; 38(10):879-85. DOI:10.1007/s00595-008-3760-4 · 1.21 Impact Factor
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    The Turkish journal of gastroenterology: the official journal of Turkish Society of Gastroenterology 07/2007; 18(2):131-2. · 0.47 Impact Factor
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    ABSTRACT: Intraabdominal adhesion formation and prevention is one of the major conflicts of modern surgery. We aimed to determine the effects of powdered gloves versus powder-free gloves and hyaluronate/carboxymethylcellulose membrane (H/CMCm) in a rat caecal serosal abrasion model. Sixty wistar albino rats were subjected to a standardized lesion by caecal abrasion model. In group 1, the procedure was performed with sterile powdered gloves. In group 2, the procedure was performed with powder-free sterile gloves. The H/CMCm was applied directly to the abraded caecum in group 3. Formation of adhesions were determined on one half of the animals from each group on the 7th postoperative day, and on the other half on the 15th postoperative day. There was a statistically significant difference between the adhesion scores on day 7 and 15 in groups 1 and 2 (p = 0.005, p = 0.007). There was no significant difference in adhesion scores on day 7 and 15 in group 3 (p = 0.145). The mean adhesion score was significantly higher in group 1 (powdered glove group) than group 2 (powder-free glove group) and group 3 (powder-free glove plus H/CMCm) on postoperative day 7 (p = 0.001). However, no significant difference was found between groups regarding adhesion scores on postoperative day 15 (p = 0.607). The comparisons of group 2 versus group 3, both on postoperative day 7 (p = 0.051) was not statistically significant, whereas a significant difference was detected between group 1 versus group 2 and group 3 on postoperative day 7 (p = 0.013, p = 0.001). Our experiment shows that the use of powder-free gloves may be as beneficial as Seprafilm in preventing postoperative adhesion formation.
    Asian Journal of Surgery 05/2007; 30(2):96-101. DOI:10.1016/S1015-9584(09)60139-1 · 0.76 Impact Factor
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    ABSTRACT: We aimed to clarify the effects of different enteral nutrients (regular chow, complete balanced nutrition, complete balanced nutrition enriched with fiber and immune-enhancing diet) on ileal anastomotic healing and bacterial translocation (BT) in the stress-free metabolic state. The study was carried out with 40 male Wistar Albino Rats weighing between 250-300 g in four groups of 10 animals each. After terminal ileum anastomosis, animals were fed with early enteral nutrients using regular chow (group 1), Ensure ® (group 2), Enrich ® (group 3) and Impact Oral ® (group 4) for 7 days. There were no significant differences among the groups in bursting pressure (BP) (p=0.070) and BT (p=0,460). The difference between the groups according to hydroxyproline (HP) level was significant (p=0,042). The HP level of Group 4 (0,978–0,077 mg/g dry tissue) was lower than that of the control (1,544–0,155 mg/g dry tissue) group (p=0,008). Under normal conditions without stress, we could not demonstrate the superior effects of early enteral feeding with specialized enteral preparations or immunonutrients over normal diets on ileal anastomosis when the BP and BT were compared. The differences of the hydroxyproline levels may originate from local promoter effects of the nutrients on the intestinal mucosa and luminal environment.
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    ABSTRACT: Even lipomas are the most common mesenchymal benign tumors of the gastrointestinal tract, symptomatic colonic presentation is rare. Herein, we evaluated four patients suffering from various size of colonic lipomas and approached by different therapeutic modalities.
    World Journal of Gastroenterology 09/2006; 12(31):5075-7. · 2.43 Impact Factor
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    ABSTRACT: Starting continuous ambulatory peritoneal dialysis (CAPD) immediately after insertion of a peritoneal dialysis catheter is essential in end-stage renal disease (ESRD). In relation to the insertion methods, various mechanical and infectious complications may arise. In this study, we aimed to compare early complications of the laparoscopic tunneling method of CAPD placement that we developed recently in order to minimize the complications, with those of the conventional percutaneous method. Included in this study were 12 consecutive patients with ESRD to whom we introduced catheters for CAPD by way of laparoscopic tunneling between April 2003 and July 2003 and followed up for at least 6 months, and 30 patients to whom the catheters were placed percutaneously in the same time period with the same follow-up time. The complications seen during the first 6 months after catheter placement with these two different methods were compared. In all of the subjects, dialysis was started soon after catheter placement. No peroperative morbidity was seen in any of the patients. While with laparoscopic tunneling method no mechanical problem was seen, the percutaneous method resulted in early leakage in 10%, pericatheter bleeding in 3.3%, and hernia in 3.3% of the patients. As infectious complications, peritonitis occurred as one episode/36 patient-months in laparoscopic tunneling and one episode/22.5 patient-months in percutaneous method; catheter insertion site infection was seen in none in the laparoscopic method, while one episode/90patient-months was seen with the percutaneous method. Tunnel infection did not arise in any of the subjects. The authors of this study think that the peritoneal tunneling method for introducing CAPD, which has been recently developed and began to be routinely used by them, is rather safe in terms of early complications.
    Renal Failure 02/2006; 28(1):37-42. DOI:10.1080/08860220500461237 · 0.78 Impact Factor
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    ABSTRACT: The aim of the present study was to test the effectiveness of aprotinin to reduce bleeding in liver resection of guinea pigs with acutely injured hepatocyte using intraperitoneal d(+)Galactosamine. Thirty-two guinea pigs were divided equally into four groups. Group 1 was the control group. Group 2 received intraperitoneal D(+)galactosamine. Group 3 received intraperitoneal d(+)galactosamine prior to a standard liver resection. Group 4 received 10.000 KIU/kg aprotinin infusion via jugular catheter in 10 min prior to standard liver resection in pretreated animals with d(+)galactosamine. All of the measurements and surgical interventions were made 24 h after the administration of d(+)galactosamine. Bleeding amounts were recorded in groups 3 and 4 for 1 h by weighing the sponges placed into the abdomen. Liver function tests, histologic, haematologic and fibrinolytic parameters were measured. Hepatocyte injury and hyperfibrinolysis were seen at the end of 24 h after application of d(+)galactosamine in groups 2, 3, and 4. Statistically significant amounts of bleeding from the resected livers were observed in group 3 and 4. In group 4, the bleeding was reduced (P < 0.05) and fibrinolytic parameters were normalized (P < 0.05) with aprotinin infusion. Significant bleeding diathesis and hyperfibrinolysis occurred in groups 2, 3, and 4, which had hepatocyte injury proved with histopathologic and haematologic tests. Prothrombin time (PT) and partial thromboplastin time (aPTT) in groups 3 and 4 were fivefold higher than that in the control group (P = 0.0001). The bleeding tendency according to high PT and aPTT levels were continued with application of aprotinin while reduction of bleeding was seen. Parenchymatous organ haemorrhage in acute liver failure or hyperfibrinolytic conditions could be reduced significantly with aprotinin without procoagulant effect.
    ANZ Journal of Surgery 04/2005; 75(4):239-43. DOI:10.1111/j.1445-2197.2005.03334.x · 1.12 Impact Factor
  • M Comert, A Borazan, E Kulah, B Hamdi Uçan
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    ABSTRACT: Mechanical outflow obstruction and leakage from the exit site of the catheter are two common complications of continuous ambulatory peritoneal dialysis. To lessen these complications and to achieve immediate use of the catheter, we developed a new laparoscopic technique for catheter placement. A total of 12 consecutive patients with end-stage renal failure were included in this study between April 2003 and July 2003. The average age of the patients was 42.4 years (range, 37-72). Patients were excluded only if a serious risk for general anesthesia was found. Using two 5-mm ports and a 3.3-mm mini-laparoscope, a peritoneal dialysis catheter was passed through a preperitoneal tunnel before the tip of the catheter was introduced into the pelvis. Routine peritoneal dialysis was started immediately after the operation while the patients were still in the operating room. The mean operating time was 18.6 min (range, 12-37). There was no operative morbidity. The mean follow-up period was 4.3 months (range, 3-7). No leakage of the dialysate liquid or outflow obstruction was observed during this period. The advantages of this method include accurate placement, preperitoneal fixation, and immediate use of the catheter for routine peritoneal dialysis. We also believe that because of the preperitoneal fixation of the catheter, this technique will decrease outflow obstruction, which usually occurs due to omental wrapping or displacement of the catheter tip.
    Surgical Endoscopy 03/2005; 19(2):245-8. DOI:10.1007/s00464-003-9302-7 · 3.31 Impact Factor
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    ABSTRACT: This study was designed to determine the effects of different surgeons on the experimental anastomosis studied in rats. Sixteen Wistar-albino rats were equally separated into two groups. The rats operated on by the first surgeon were coded Group 1 and operated on by the other surgeon were coded Group 2. Both surgeons were trained on the gastrointestinal surgery. The procedure of the study were standardized and dictated to the surgeons. Bursting pressure and tissue hydroxyproline content were determined as parameters of the anastomotic strength and healing on the seventh day postoperatively. The bursting pressures were measured with a digital manometer and anastomotic lines were removed to measure tissue hydroxyproline level. While hydroxyproline value in the first group was 105.60 +/- 9.43 microg/mg dry tissue, it was found to be 104.02 +/- 17.26 microg/mg dry tissue in the second group and this difference was not statistically significant (p=0.521). The bursting pressure was determined as 240.71 +/- 11.65 mmHg in the first group, 190.75 +/- 14.09 mmHg in the second group and the difference was statistically significant (p=0.002). The anastomotic resistances to intraluminal pressure were found statistically different whereas tissue hydroxyproline levels were normal between the groups. These results make us to consider mechanical differences occur related to the surgeons in the studies performed with the same technical detail.
    Hepato-gastroenterology 01/2004; 50 Suppl 2:ccxxxv-ccxxxvii. · 0.91 Impact Factor
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    ABSTRACT: This study was designed to determine whether there exists a difference between in vivo and in vitro measurements of bursting pressure (BP) of experimental intestinal anastomosis studied in Wistar-albino rats. In the first group (n=8), the BP was measured using in vivo method without detaching the adhesions around the anastomosis. BP was determined with digital manometer, and then anastomotic region was removed to measure tissue hydroxyproline (HP) levels. In the second group (n=8), the BP was measured with in vitro method after the segment of intestine including the anastomosis was dissected and isolated. The isolated specimen was then submerged in a normal saline bath. BP was determined with a digital manometer and anastomotic region was removed to measure tissue HP levels. While HP value in the first group was 105.60 +/- 9.43 microg/mg dry tissue, it was found to be 121.11 +/- 16.26 microg/mg dry tissue in the second group and this difference was not statistically significant (p=0.195). The BP was determined as 240.71 +/- 11.65 mmHg in the first group, 144.71 +/- 16.41 mmHg in the second group and the difference was statistically significant (p=0.002). The anastomotic resistances to intraluminal pressure were found to be statistically different whereas tissue HP levels were normal between the groups. These results make us consider that mechanical changes occur about the isolated anastomotic line and dissection of adhesions weakens the anastomosis.
    Hepato-gastroenterology 01/2004; 50 Suppl 2:ccxxxii-ccxxxiv. · 0.91 Impact Factor