Refik Ayten
Fırat University
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Featured researches published by Refik Ayten.
World Journal of Surgery | 2005
Refik Ayten; Osman Doğru; Cemalettin Camci; Erhan Aygen; Ziya Çetinkaya; Handan Akbulut
Intestinal obstruction is responsible for 3% of admissions to hospital emergency surgical departments, but it is difficult to distinguish simple obstruction from strangulation. Simple criteria for this distinction are sought. In this experimental study, procalcitonin, a known marker of bacterial inflammation, was used to detect strangulation. The predictive value of procalcitonin for small bowel strangulation was evaluated. Thirty male New Zealand rabbits (mean weight: 3.0 kg) were divided into three groups. In the first (control) group, only laparatomy was performed. In the second group, simple obstruction was created by ligating a 10-cm distal ileum segment. In the third group, distal strangulation was created by ligating a 10-cm distal ileum segment with the mesentery. Blood (1 cc) was taken from the right auricular vein of each animal for measuring the procalcitonin level. In both the control group and the simple obstruction group the procalcitonin levels were normal. In the strangulation group, elevation of procalcitonin was detected after 30 minutes, and the elevation was statistically significant at 120th minute compared with the control and simple obstruction groups. In patients with small bowel obstruction, measurement of procalcitonin levels is easy to perform and can be used in the follow-up. A more extensive clinical study is needed to evaluate the accuracy of the test as a marker.
Diseases of The Colon & Rectum | 2009
Refik Ayten; Ziya Çetinkaya; Mustafa Girgin; Ibrahim Hanifi Ozercan; Bilal Ustundag; Erhan Aygen
PurposeThe objective of this pilot study was to establish an animal model for intra-abdominal infection and to examine the effect of sildenafil on anastomotic healing of the left colon and intra-abdominal adhesion formation.MethodsFourteen Winstar rats underwent colonic transsection and primary anastomosis after performing intra-abdominal infection. Rats were divided into two groups: Group 1 (nu2009=u20097): intra-abdominal infection, resection, and anastomoses; Group 2 (nu2009=u20097): intra-abdominal infection, resection, anastomoses, and sildenafil. Anastomotic bursting pressures, hydroxyproline levels, histopathologic grading, and abdominal adhesions were accessed on the postoperative Day 7.ResultsAnastomotic healing was found to be improved in terms of a bursting pressure (Pu2009=u20090.02). Histopathological examination revealed an increase in angiogenesis (Pu2009=u20090.007). Moreover, intra-abdominal adhesions were significantly less in rats given sildenafil (Pu2009=u20090.03).ConclusionSildenafil may improve anastomotic healing of the left colon and diminishes peritoneal adhesion formation in the presense of abdominal infection.
International Surgery | 2012
Mustafa Girgin; Burhan Hakan Kanat; Refik Ayten; Ziya Çetinkaya; Zekiye Kanat; Ahmet Bozdağ; Ahmet Türkoğlu; Yavuz Selim Ilhan
Pilonidal disease has been treated surgically and by various other methods for many years. The most important problem associated with such treatment is recurrence, but cosmetic outcome is another important issue that cannot be ignored. Today, crystallized phenol is recognized as a treatment option associated with good medical and cosmetic outcomes. We hypothesized that the addition of laser depilation to crystallized phenol treatment of pilonidal disease might increase the rate of success, and this study aimed to determine if the hypothesis was true. Patients who were treated with crystallized phenol and 755-nm alexandrite laser depilation were retrospectively analyzed. In total, 42 (31 male and 11 female) patients were treated with crystallized phenol and alexandrite laser depilation and were followed up between January 2009 and January 2012. In all, 38 patients (90.5%) had chronic disease and 4 (9.5%) had recurrent disease. Among the patients, 26 (61.9%) recovered following 1 crystallized phenol treatment, and the remaining patients had complete remission following repeated treatment. Some patients needed multiple treatments, even up to 8 times. None of the patients had a recurrence during a mean 24 months (range, 6-30 months) of follow-up. Whatever method of treatment is used for pilonidal disease, hair cleaning positively affects treatment outcome. The present results support the hypothesis that the addition of laser depilation (which provides more permanent and effective depilation than other methods) to crystallized phenol treatment (a non-radical, minimally invasive method associated with very good cosmetic results) can increase the effectiveness of the treatment and also reduce the recurrence rate of the disease.
Appetite | 2009
Ziya Çetinkaya; Suleyman Aydin; Yusuf Ziya Cerrahoglu; Refik Ayten; Fazilet Erman; Erhan Aygen
This study was designed to measure the levels of serum and saliva ghrelin concentrations before and after surgery in an attempt to clarify whether this hormone plays any significant roles in acute appendicitis and cholelithiasis patients when compared with healthy controls. Samples were obtained from 20 patients with appendicitis, 10 patients with cholelithiasis before and after operation, and 16 healthy controls. The levels of ghrelin (acylated) were measured by means of a RIA assay. The results revealed that preoperative levels of ghrelin in saliva and serum were significantly decreased with respect to post-op in patients undergoing appendectomy, and control levels. This was also the case when the preoperative ghrelin concentrations in patients with appendicitis were compared with those having choelithiasis. Taken together, decreased ghrelin concentration in preoperative appendicitis might be a causative factor for the loss of appetite observed in an acute inflammatory condition such as acute appendicitis. However, further studies are necessary to reveal the exact mechanisms behind this observation.
World Journal of Emergency Surgery | 2006
Ziya Çetinkaya; Kazım Esen; Ibrahim Hanefi Ozercan; Bilal Ustundag; Refik Ayten; Erhan Aygen
BackgroundIschemia is the most important factor compromises wound healing in colonic anastomosis. Mesenteric vessels are ligated at first while performing colonic resection and following anastomosis. Therefore blood supply of the related segments of colon temporarily interrupted and ischemia can easily occur. This study was carried out to explore whether Bosentan, an endothelin-receptor antagonist, can eliminate vasoconstruction, increase blood flow in the splanchnic area and anastomotic region and therefore possibly facilitate wound healing and prevent intra-abdominal adhesion formation.MetodsStudy is conducted on 30 female Wistar-Albino rats weighing 180–240 gr. Rats were allocated into three groups. Group 1 (n = 10) recevied full-thickness resection of the left colon and end-to-end anastomosis. In Groups 2 (n = 10) and 3 (n = 10), vessels of 2–3 cm segment of the left colon were ligated, indications of necrosis of that segment were expected, followed by resection and end-to-end anastomosis. Two milliliter of saline and 5 mg/kg Bosentan was given intraperitoneally in Group 2 and 3, respectively. On postoperativ day 6, intra-abdominal adhesions were scored. Healing of anastomosis, anastomotic bursting pressures, tissue hydroxyproline levels and histopatologically healing scores were assessed.ResultsMacroscopic adhesion score in Group 3 was lower than the remained groups (p < 0.05). Tissue hydroxyproline levels were significantly higher in Group 3 compared to the Groups 1 and 2 (p < 0.001). Mean anastomotic bursting pressures were 200 mmHg, 164 mmHg and 240 mmHg in Groups 1, 2 an 3, respectively (p < 0.05 between Groups 1 and 3; p < 0.001 between Groups 2 and 3). Histopathologically, healing scores of Group 1 were significantly higher than the other groups (p < 0.05 group 1–3, group 2–3).ConclusionBosentan increases anastomotic healing of ischemic colonic anastomosis and decreases intra-abdominal adhesion formation.
Gastroenterology Research and Practice | 2011
Murat Basbug; Nurullah Bülbüller; Cemalettin Camci; Refik Ayten; Erhan Aygen; Ibrahim Hanifi Ozercan; Zulfu Arikanoglu; Sami Akbulut
Aims. This study determined the effects of a single dose of bevacizumab, an antiangiogenic recombinant monoclonal antibody that specifically targets vascular endothelial growth factor (VEGF), on adhesion formation in the rat cecal abrasion model. Methodology. Thirty female Wistar albino rats (200–224u2009g) were divided into three groups. All rats underwent laparotomy at which time cecal wall abrasion and abdominal wall injuries were induced. Group I (control) underwent only the abrasion procedure; Groups II and III received saline or bevacizumab intraperitoneally, respectively, following the abrasion. The rats were killed on postoperative day 7, and the severity of adhesions was evaluated, together with histopathological fibrosis parameters and immunohistochemical staining to identify the VEGF receptor. Results. The mean adhesion severity score in Groups I–III was 2.5 ± 0.52, 2.4 ± 0.69, and 0.7 ± 0.82, respectively; the score in Group III was significantly lower than that in Groups I (P < 0.001) and II (P < 0.001). In the histopathological evaluation, the mean fibrosis score in Group III was significantly lower that the scores in Groups I (P < 0.001) and II (P < 0.001). VEGF staining of the adhesion areas in Group III was significantly lower than that in Groups I (P < 0.001) and II (P < 0.001). Conclusion. Bevacizumab decreases adhesion formation following laparotomy in rats by blocking VEGF receptor occupancy.
The Turkish journal of gastroenterology | 2014
Burhan Hakan Kanat; Refik Ayten; Suleyman Aydin; Mustafa Girgin; Ziya Çetinkaya; Yavuz Selim Ilhan; Mesut Yur; Zekiye Catak
BACKGROUND/AIMSnDue to risk of morbidity and mortality, various tests and scoring systems used in the assessment of the diagnosis and severity of acute pancreatitis disease are gaining more importance every day. Most of the current scoring systems, validated by various parameters, have a sophisticated and complex structure. Research is ongoing to establish a method to diagnose the disease and determine the severity by using different and simple parameters. In this trial, we aimed to investigate the role of the orexigenic ghrelin and anorexigenic obestatin hormones, if any, on the diagnosis and assessment of the severity of acute pancreatitis.nnnMATERIALS AND METHODSnA total of 30 patients hospitalized between September 2009 and September 2010 with a diagnosis of acute pancreatitis (AP) and 25 healthy volunteers were enrolled in the trial with a prospective and randomized design. The patients were classified in two groups, mild (Ranson ≤3 and / or Apache II ≤8) and severe (Ranson >3 and/or Apache II >8) cases, as per the Ranson and Apache-II criteria; the ghrelin and obestatin levels in blood samples obtained from the patients were measured using the ELISA method.nnnRESULTSnTwenty-two of the 30 patients (73%) were regarded as mild pancreatitis cases, while 8 cases (27%) were diagnosed as severe pancreatitis. Comparison of the mild and severe pancreatitis groups did not reveal a statistical difference between the two groups in terms of acylated and de-acylated ghrelin values on presentation and following the initiation of oral feeding. Similarly, no significant difference was found in the comparison of the patient and the control groups in terms of acylated and de-acylated ghrelin values on presentation (p=0.863). On the other hand, acylated and de-acylated ghrelin values after initiation of oral feeding were observed to be higher in the patient group (p=0.001, p=0.000). Comparison of these two groups revealed a significant difference in obestatin values, both on presentation and after initiation of oral feeding (p=0.002 and p=0.000).nnnCONCLUSIONnConsistently high serum ghrelin values during pancreatic inflammation suggest that ghrelin may be used as an adjunctive parameter in the monitoring of the course of the disease. On the other hand, high obestatin values in patients on presentation indicate that this hormone is a more significant parameter in terms of diagnosis. However, no correlation was established between these two peptide hormones and the severity of AP.
Canadian Journal of Surgery | 2013
Akan Yenicerioglu; Ziya Çetinkaya; Mustafa Girgin; Bilal Ustundag; Ibrahim Hanefi Ozercan; Refik Ayten; Burhan Hakan Kanat
BACKGROUNDnIn acute pancreatitis, oxygen free radicals (OFRs) and cytokines have been shown to play a role in the failure of pancreatic microcirculation and the development of local tissue damage. We studied the effects of trimetazidine (TMZ), a potent antioxidant and anti-ischemic agent, on acute pancreatitis.nnnMETHODSnRats were randomized into 3 groups: a control group (n = 15), a study group (n = 15) in which acute pancreatitis was induced with with L-arginine, and a treatment group (n = 15) in which pancreatitis was induced and treated with TMZ intraperitoneally. The rats were followed for 24 hours. At the 24th hour we determined serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), amylase, lactate dehydrogenase (LDH), interleukin 1-β (IL-1β), interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α), and the pancreatic tissues were analyzed histopathologically.nnnRESULTSnThe AST (p < 0.001), ALT (p < 0.01), amylase (p < 0.001), LDH (p < 0.01), TNF-α (p < 0.01), IL-1β (p < 0.001) and IL-6 (p < 0.001) levels, and pancreatic tissue edema (p < 0.01), hemorrhage (p < 0.05), acinar cell necrosis (p < 0.001) and level of perivascular inflammation (p < 0.01), were significantly lower in the treatment group than the study group.nnnCONCLUSIONnTrimetazidine markedly decreases biochemical and histopathologic changes during the early stages of acute pancreatitis, thus preserving the pancreas histologically.
Diseases of The Colon & Rectum | 2005
Erhan Aygen; Cemalettin Camci; Ali Sait Durmus; Osman Doğru; Ömer Topuz; Refik Ayten; Ahmet Ayar
PURPOSEAlthough the exact pathogenesis of anal fissure is not known, hypertonicity of the internal anal sphincter might be involved in its pathogenesis as main event. To gain information about possible usefulness of the novel, smooth-muscle–relaxing drug, sildenafil, in chronic anal fissure, we investigated the effect of sildenafil citrate on acetylcholine-induced contractility of internal anal sphincter isolated from dogs.METHODSInternal anal sphincter strips were taken from German shepherd dogs and suspended in a tissue bath filled with Krebs solution at 37°C (pH 7.4) continuously bubbled with 95 percent oxygen and 5 percent carbon dioxide, and isometric contractions were recorded. Contractions were evoked by 10 μM acetylcholine, and the effects of different concentrations of sildenafil citrate (0.1, 0.3, and 1 mM) on the isometric tension of each internal anal sphincter strip were examined. The statistical significance was analyzed by one-way analysis of variance.RESULTSPretreatment with sildenafil citrate (0.1 mM) attenuated contractile response to acetylcholine (n = 3), which were significantly weak compared with the maximum contractile response to the acetylcholine alone (610 ± 110 mg vs. 2,825.17 ± 416 mg; n = 12; P < 0.05). Sildenafil citrate also significantly inhibited the acetylcholine-induced contractions in a dose-dependent manner when applied after.CONCLUSIONSThis experimental in vitro study showed that sildenafil citrate relaxes acetylcholine stimulated contractions of isolated dog internal anal sphincter. This may be of importance for raising the possibility that sildenafil cit-rate may have future potential in the treatment of chronic anal fissure. Further studies are needed for a conclusive decision on possible usefulness of sildenafil citrate in patients with chronic anal fissure.
Hepato-gastroenterology | 2011
Cuneyt Kirkil; Nurullah Bülbüller; Erhan Aygen; Murat Basbug; Refik Ayten; Necip Ilhan; Yavuz Selim Ilhan; Sami Akbulut
BACKGROUND/AIMSnMalnutrition adversely affects the postoperative outcome of patients with gastrointestinal cancer. Therefore, the malnourished cancer patients are supported by enteral or parenteral nutrition. In this study, we aimed to investigate the effects of preoperative nutritional supports on total antioxidant capacity (TAC) in malnourished patients with gastrointestinal (GI) cancers.nnnMETHODOLOGYnSeventy-five malnourished patients with GI cancers and 25 patients with non-cancer surgical problems were included in the study. The dietary of cancer patients were supported with immune-enhancing enteral solution in group II or standard enteral solution in group III and with parenteral solution in group IV. Plasma TAC levels were measured prior and after nutritional support. Data were expressed as mmol Trolox eq./L.nnnRESULTSnThe mean TAC levels of groups before treatment were 1.10±0.17, 0.92±0.19, 0.89±0.17 and 0.92±0.18, respectively. It was significantly higher in group I than others. The mean TAC levels of supported groups after treatment were 1.11±0.20, 1.08±0.21 and 1.09±0.27, respectively. Although there was a statistically significant increase in TAC after treatment in group II and III, it was not statistically significant in group IV.nnnCONCLUSIONSnIt was concluded that preoperative nutritional support with standard or immune-enhancing enteral solutions significantly increased TAC levels of malnourished patients with GI cancers.