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Dive into the research topics where Hayrettin Öztürk is active.

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Featured researches published by Hayrettin Öztürk.


Journal of Pediatric Surgery | 2003

The effects of nitric oxide on the expression of cell adhesion molecules (ICAM-1, UEA-1, and tenascin) in rats with unilateral testicular torsion.

Hayrettin Öztürk; Hüseyin Büyükbayram; Enver Ozdemir; Aydın Ketani; Ahmet Gürel; Abdurrahman Onen; Selcuk Otcu

BACKGROUND/PURPOSE The aim of this study was to determine the effects of nitric oxide (NO) on the expression of adhesion molecules in the early course of testicular I-R injury in rats. METHODS Forty male Sprague-Dawley rats were separated into 4 groups, each containing 10 rats. A sham operation was performed in group 1 (control). In group 2 (I-R), after 6 hours of unilateral testicular torsion, 1-hour detorsion of the testis was performed. In group 3 (I-R/L-NAME), after performing the same surgical procedures as in group II, L-NAME was given for 30 minutes. In group 4 (I-R/Mol), after performing the same surgical procedure (torsion and detorsion) as in group II, molsidomine, an NO donor, was infused for 30 minutes. Then, ipsilateral orchiectomies were performed to measure the tissue levels of malondialdehyde (MDA) and NO and to make histologic examination. RESULTS MDA values and the testicular injury score decreased and NO values increased in the I-R/Mol-treated group compared with other experimental groups. The tenascin expression in the interstitial space and basement membrane of the tubuli seminiferi were milder in the I-R/Mol group compared with that of the I-R and the I-R/L-NAME. The acrosomes of the spermatids in I-R and I-R/L-NAME groups were stained mildly by lectin. In the I-R and I-R/L-NAME groups, the interstitial spaces, basement membrane of the tubuli seminiferi, and sertoli and germinal cells in testicular tissue were stained intensely by ICAM-1. CONCLUSIONS The expression of adhesion molecules such as tenascin, lectin, and ICAM-1 in the torted testicular tissue may be a pathophysiologic sign of inflammation. NO regulates adhesion molecules expression.


BJUI | 2001

The protective effects of nitric oxide on the contralateral testis in prepubertal rats with unilateral testicular torsion

Ali Ihsan Dokucu; Hayrettin Öztürk; Enver Ozdemir; A. Ketani; Hüseyin Büyükbayram; S. Yücesan

Objective To investigate histological changes in the contralateral testis of rats with unilateral testicular torsion and the protective effects of nitric oxide (NO) on possible damage.


Acta Chirurgica Belgica | 2004

The preventive effect of Rofecoxib in postoperative intraperitoneal adhesions.

Mustafa Aldemir; Hayrettin Öztürk; Erten C; Hüseyin Büyükbayram

Abstract Background: Previous studies showed that nonsteroidal anti-inflammatory (NSAi) drugs suppressed prostaglandin synthesis and were able to prevent adhesion formation following surgical trauma to the peritoneum. The selective suppression innammatory cascade may prevent adhesion formation. Therefore, we planned this study to experimentally evaluate the effects of Rofecoxib, the selective cyclo-oxygcnase-2 inhibitor, in postoperative intraperitoneal adhesions in an animal model. Methods: Male Sprague-Dawley rats were divided into three groups of 10. All rats underwent midline laparotomy under ketamine anaesthesia (25 mg/kg im). In group 1 (n = 10), the sham operation group (SG) ; abdominal walls were closed without any process after 2 minutes. In Group 2 (n = 10), the control group (CG) ; standard serosal damage was constituted and the abdominal wall was closed. In group 3 (n = 10), the COX-2 group (COXG), after serosal damage, the abdominal wall was closed. A 12 mg/kg/day dose of was given orally to the rats during one week. On the 7th postoperative day, all rats were sacrificed and intra-abdominal adhesions were evaluated both macroscopically and microscopically. Results: Macroscopically, no serious adhesion formations were seen in the SG. Multiple adhesion format ions of the CG were significantly more than those of the SG (p < 0.0001). It was determined that adhesions of the COXG diminished (p < 0.0001) when macromorphological adhesion scale results of the COXG were compared with those of the CG. The adhesion scores of the CG were compared microscopically with those of the COXG and granulation tissue formation and fibrosis in the COXG were found to be significantly less than those of the CG (respecti vely p = 0.002, p < 0.0001). Conclusions: We were of the opinion that Rofecoxib, the selective cyclo-oxygenase inhibitor, was effective in the prevention of postoperative peritoneal adhesions.


Pediatric Surgery International | 2003

When to resect and when not to resect an asymptomatic Meckel's diverticulum: an ongoing challenge

Abdurrahman Onen; Murat Kemal Cigdem; Hayrettin Öztürk; Selcuk Otcu; Ali Ihsan Dokucu

Abstract. To determine the morbidity and mortality of Meckels diverticulum (MD) as a cause of acute abdominal disorders and to evaluate the relationship between patient age, MD complications, and postoperative complications. We reviewed 74 patients who underwent surgery between 1990 and 2000 for an acute abdominal syndrome with a MD diagnosed intraoperatively. Forty children were treated before 1995 and reviewed retrospectively, while the remaining 34 were reviewed prospectively. The average age was 4.8 years; the male/female ratio was 2.5/1; 34 (46%) were less than 2 years old, 32 were between 2 and 8 years, and 8 were older than 8 years. None of the symptoms was suggestive of the diagnosis of MD. Thirty-nine MDs were asymptomatic (21 intussusception, 18 volvulus), but all were the secondary cause of the acute abdomen. The remaining 35 children had a symptomatic MD (diverticulitis in 14, diverticular bleeding in 11, diverticular perforation in 10). The risk of complications due to a MD occurring in children under 2 years and between 2 and 8 years of age was significantly higher compared to children older than 8 years (P = 0.02). Postoperative complications occurred more commonly in children between 2 and 8 years of age compared to other patients. There is thus an increased risk of morbidity in a symptomatic MD in patients less than 2 and between 2 and 8 years of age, and there is no predictive factor for the development of diverticular complications. Resection of the MD is recommended in all children younger than 8 years, including asymptomatic ones, in the absence of absolute contraindications.


Surgery Today | 2003

Diagnostic delay increases morbidity in children with gastrointestinal perforation from blunt abdominal trauma

Hayrettin Öztürk; Abdurrahman Onen; Selcuk Otcu; Ali Ihsan Dokucu; Yusuf Yagmur; Mete Kaya; Selçuk Yücesan

Abstract.Purpose: Intestinal perforation due to blunt abdominal trauma is rarely seen in children and delayed diagnosis is a major concern. Because the potential risk factors affecting morbidity are not well known, we evaluated whether diagnostic delay increases morbidity in gastrointestinal perforation from blunt abdominal trauma in children. Methods: Twenty-nine children with gastrointestinal perforation caused by blunt abdominal trauma, admitted to our clinic between 1983 and 2001, were retrospectively evaluated by analyzing the relationship between overall morbidity and potential risk factors. Results: There were 23 boys and 6 girls. Most of the injuries were caused by falls and motor vehicle accidents. The jejunum was the most frequent site of perforation followed by the ileum. Simple closure was the most common surgical procedure. Postoperative complications developed in five patients (17%) and included wound infections in two, wound dehiscence in one, and adhesive small bowel obstruction in two. Potential risk factors such as trauma mechanism, the presence of shock on admission, and associated organ injury were not significantly correlated with postoperative complications, whereas a period of delay exceeding 8 h and an Injury Severity Score (ISS) exceeding 15 were significantly related to septic complications (P < 0.05). The relative risk of a septic complication developing was higher than 2 for the following risk factors: a fall from a flat-roofed house and a time delay before operative intervention. There were three deaths (10%) in this series, caused by sepsis in two patients and head injury in one. Conclusion: These findings suggest that rapid diagnosis and treatment is important for preventing complications in patients with intestinal perforation caused by blunt abdominal trauma. A delay exceeding 8 h and an ISS score exceeding 15 were related to significant septic complications, and falls from flat-roofed houses are an important public safety risk in Turkey.


Renal Failure | 2007

Nitric Oxide Regulates Expression of Sonic Hedgehog and Hypoxia-Inducible Factor-1α in an Experimental Model of Kidney Ischemia-Reperfusion

Hayrettin Öztürk; Mehmet Cudi Tuncer; Hulya Ozturk; Hüseyin Büyükbayram

This study was designed to determine the effect of L-arginine on hypoxia inducible factor alpha (HIF-1 α) and Sonic hedgehog (Shh) levels considered to be involved in the development of ischemia/reperfusion (I/R) injury. Unilaterally nephrectomized Sprague-Dawley rats were subjected to 60 minutes of left renal ischemia followed by 45 minutes of reperfusion. Group 1 were sham-operated animals; group 2, I-R/Untreated animals; and group 3, I-R/L-Arg-treated animals. Serum creatinine, blood urea nitrogen (BUN), and kidney malondialdehyde (MDA) levels were determined as well as examining the kidneys histologically. The treatment of rats with L-Arg produced a significant reduction in the levels of BUN, creatinine, MDA, and histopathological score compared to renal I/R groups. The Shh expression in the tubulus epithelia were intensely increased in the I-R/L-Arg group when compared to that of the Sham-control and the I-R/untreated groups. Additionally, the HIF-1α expression in the tubulus epithelia and the interstitial spaces were intensely increased in the I-R/L-Arg group. These findings suggest that NO reduces the renal dysfunction associated with I/R of the kidney and may act as a trigger to induce Shh and HIF-1 activity.


International Urology and Nephrology | 2001

The effects of the nitric oxide donor molsidomine prevent in warm ischemia-reperfusion injury of the rat renal — A functional and histophatological study

Hayrettin Öztürk; Mustafa Aldemir; Hüseyin Büyükbayram; Ali Ihsan Dokucu; Selç Otçu

Aim of this experimental study is to verify the protective effect of molsidomine on the renal function and structural modifications in the ischemia-reperfusion rat kidney. Sixty-eight male Sprague-Dawley rats, which were right nephrectomized and occluded left renal artery for 60 minutes were used. Group I (n = 10) Sham-Operated animals, which only underwent right nephrectomy. Group II (n = 20) Untreated ischemic rats, which underwent left renal ischemia by occlusion of the renal artery for 60 minutes before blood flow was restored. Group III (n = 18) Molsidomine treated ischemic rats, Group IV (n = 20) L-NAME (NG-nitro-L-arginine methyl ester) treated ischemic rats. Serum creatinine and blood urea nitrogen (BUN) were measured daily and biopsies were obtained from the remaining left kidneys. At seventh day, 55% and50% of the rats remained alive at the G-II and G-IV respectively. Molsidomine treated rats (G-III) were alive and healthy at day 7. The serum creatinine and BUN levels were significantly higher in G-II and G-IV when compared with the sham-operated group (G-I). G-III rats showed a rapid return to the normal serum creatinine and BUN values on postoperative days 1, 2, 3 and 4. The obtained values in G-III were significantly lower in comparison to the values of G-II and G-IV. The most severe damage (grade3 to 4) was determined in the kidneys of rats from GII or GIV. The degree of renal tubular damage in GIII was evaluated as grade 1 or 2 tubular damage according to Jablonkskis scale. Our findings suggested that the administration of molsidomine may vanquish the pernicious effects of warm ischemia on kidney structure and function.


BJUI | 2002

Blunt renal trauma in children with previously undiagnosed pre‐existing renal lesions and guidelines for effective initial management of kidney injury

Abdurrahman Onen; Mete Kaya; M.K. Ciǧdem; Selcuk Otcu; Hayrettin Öztürk; Ali Ihsan Dokucu

Objectives To record pre‐existing renal lesions (PERL) found incidentally during evaluation for blunt renal trauma in children, determine their importance, suggest guidelines for the effective initial management of children with significant renal trauma and to evaluate the role of temporary percutaneous nephrostomy tube drainage (TPND) in these patients.


Gastric Cancer | 2002

Primary gastric adenocarcinoma in a 2.5-year-old girl

Ali Ihsan Dokucu; Hayrettin Öztürk; Nihal Kilinç; Abdurrahman Onen; Yaşar Bükte; Murat Söker

Abstract.Primary gastric adenocarcinoma is extremely rare in children. Here, we report an additional case of primary adenocarcinoma, located at the lesser curvature in a girl at the age of 2.5 years. She had no family history and no apparent underlying cause for the tumor. She died 4 months after admission despite complete resection of the mass and chemotherapy.


Pediatric Surgery International | 2002

Effects of supplemental L-arginine on the intestinal adaptive response after massive small-bowel resection in rats.

Hayrettin Öztürk; Ali Ihsan Dokucu; Yusuf Yagmur; Ibrahim Sari

Abstract.To evaluate whether L-arginine methyl ester (L-Arg) can improve the structure of the small intestine and enhance adaptation in an experimental model of short-bowel syndrome (SBS), 40 Sprague-Dawley rats were divided randomly into four groups of 10 each. In one group only a laparotomy was performed (G1). The remaining 30 rats underwent 90% small-bowel resection (SBR) and formed the three experimental groups: the SBR/untreated group (G2), the SBR/L-NAME-treated group (G3), and the SBR/ L-Arg-treated group (G4). Rats in G2 received no therapeutic treatment. Rats in the SBR/L-NAME and SBR/L-Arg treated groups received N-G-nitro-L-arginine-methyl ester (L-NAME) and L-Arg intraperitoneally for 3 weeks, respectively. The animals were weighed daily. All rats underwent a relaparotomy on day 21 of the experiment. Remnant small bowel was excised and evaluated for villus height and crypt cell mitoses. After the 90% SBR, all animals had from diarrhea and weight loss between the 1st and 6th postoperative days (POD). The body weight of the SBR/L-Arg group showed significant increases at POD 10 and 21 in comparison to the SBR/untreated and SBR/L-NAME groups (P < 0.001). The rats treated with L-Arg had significantly greater villus height and crypt-cell mitoses compared to the other groups (P < 0.0001, P < 0.001). These observations suggest that L-Arg treatment increases villus height and crypt-cell mitoses after massive SBR and may play a considerable role in the mucosal adaptive response in SBS in rats.

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Hulya Ozturk

Abant Izzet Baysal University

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