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Öğe The effect of celecoxib, a selective COX-2 inhibitor, on liver ischemia/reperfusion-induced oxidative stress in rats(Wiley, 2006) Ozturk, H; Gezici, A; Ozturk, HThis study examined the effects of celecoxib on hepatic ischemia/reperfusion (I/R) injury in rats. A total of 40 male Sprague-Dawley rats weighing 190-210g were randomized into 4 groups of 10: (1) controls: data from unmanipulated animals; (2) sham group: rats subjected to the surgical procedure, except for liver I/R, and given saline; (3) I/R group: rats that underwent liver ischemia for 1 h followed by reperfusion for 45 min; (4) I-R/Celecoxib group: rats pretreated with celecoxib Q mg kg(-1), i.p.) 40 min before liver I/R. Tc-99m sulfur colloid images were used to measure the uptake ratio and perfusion index. Liver tissues were taken to determine SOD, CAT, GSH-Px, and MDA levels and for biochemical and histological evaluation. The plasma ALT, AST, GGT, and LDH activities were higher in group 3 than in group 4. The uptake ratio was significantly lower in group 3 compared to groups 1, 2, and 4. In addition, in group 4, the uptake ratio and perfusion index were also significantly higher compared to group 3. MDA values and the hepatic injury score decreased, while the SOD, CAT, and GSH-Px values increased in group 4 compared to group 3. In group 3, hepatocytes were swollen with marked vacuolization. Group 4 showed well preserved liver parenchyma with hepatocytes arranged radially around the central vein; there were regular sinusoidal structures with normal morphology without any signs of congestion. We showed that celecoxib has beneficial effects in hepatic I/R injury and may protect the liver. (c) 2005 Elsevier Ireland Ltd. All rights reserved.Öğe The effects of exogenous interleukin-4 on hypoxia-induced lung injury(Springer, 2006) Ozturk, H; Ozturk, H; Buyukbayram, H; Tuncer, MCThe aim of this study was to determine the effects of recombinant human interleukin-4 (rhIL-4) on hypoxia-induced lung injury in immature rats. The study was performed on 1-day-old Sprague Dawley rat pups. Group 1 (n=7) served as nonhypoxic controls. Group 2 (untreated, n=7) rats were subjected to hypoxia-reoxygenation (H/O) and were then returned to their mothers. Group 3 (rhIL-4 treated, n=7) rats were subjected to H/O, were returned to their mothers, and were treated with rhIL-4 (75 mu g/kg subcutaneously) for the next 3 days. All animals were killed on day 4 and lung specimens were obtained to determine the tissue level of malondialdehyde (MDA) and histological changes. In the untreated group, MDA levels were significantly increased compared to control and rhIL-4 groups. In the rhIL-4 treated group, MDA levels were not significantly different compared to control group. The rhIL-4 treated group had a significantly lower score of pathological lesions and alveolar hemorrhage grade values than the untreated group. The untreated animals had areas marked intraalveolar hemorrhage, capillary congestion, interstitial edema, and hypercellularity of lung that were not seen in the rhIL-4 treated rats. In conclusion, this study found beneficial effects of rhIL-4 in an experimental model on the hypoxia-induced lung injury.Öğe Effects of gabexate mesilate on ischemia-reperfusion-induced testicular injury in rats(Springer, 2006) Gezici, A; Ozturk, H; Buyukbayram, H; Ozturk, H; Okur, HThe aim of this study was to determine the effects of a synthetic serine protease inhibitor, gabexate mesilate (GM), in rats with ischemia-reperfusion (I-R) damage due to unilateral testicular torsion. Thirty male Sprague-Dawley rats were separated into three groups, each containing ten rats. A sham operation was performed in group 1 (control). In group 2 (I-R/untreated), 1 h detorsion of the testis was performed after 6 h of unilateral testicular torsion. In group 3 (I-R/GM), after performing the same surgical procedures as in group II, gabexate mesilate was given intravenously. In all experimental rats, ipsilateral orchiectomies were performed for histological examination and measuring the tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). MDA values and the testicular injury score decreased and SOD, CAT and GSH-Px values increased in the GM-treated group compared to the I-R/untreated group. The Tc-99m pertechnetate uptake ratio and the perfusion index were significantly decreased in the group 2 compared to the group 1 and 3 rats. In group 3, these values were significantly increased compared to group 2. Most of the specimens in the GM-treated group showed grade-I testicular injury. However, the injuries in the I-R/untreated rats varied between grade-III and grade-IV. The results of this study show that GM may play a role in reducing the injury caused by I-R.Öğe The effects of L-arginine on neurological function, histopathology, and expression of hypoxia-inducible factor-1 alpha following spinal cord ischemia in rats(Karger, 2005) Tuncer, MC; Hatipoglu, ES; Ozturk, H; Kervancioglu, P; Buyukbayram, HThe aim of this study was to investigate the effects of L-arginine (L-Arg) on neurological function, histopathology, and expression of hypoxia-inducible factor-1 alpha (HIF-1 alpha) following spinal cord ischemia in rats, and the interaction between therapy with the nitric oxide donor L-Arg and up-regulation of the expression of HIF-1 alpha. Thirty Wistar rats weighing between 200 and 250 g were divided into three groups, each containing 10 rats: group 1, sham operation; group 2, untreated ischemia-reperfusion (I-R); group 3, I-R plus L-Arg treatment. Spinal cord ischemia was applied for 20 min. There were no significant differences in mean arterial pressures, temperatures, and blood gas levels among the groups. In group 2, malondialdehyde values were significantly increased compared with groups 1 and 3. The rats with aortic occlusion in group 2 had paraplegia or paraparesis. In group 3, all animals were neurologically intact. In group 3, spinal motor neurons did not decrease significantly, and little proliferation of microglia was observed compared with those in group 2. In group 2, spinal motor neurons in ventral gray matter decreased significantly compared with those in groups 1 and 3. HIF-1 alpha-positive immunostaining was mildly detected in group 2 animals. The expression of immunoreactive cells was intensely increased in spinal cord tissue from I-R/L-Arg rats. In conclusion, our findings suggest that HIF-1 alpha-positive immunostaining may be critical factors in the pathophysiology of inflammatory spinal cord injury induced by I-R. Nitric oxide may play an important role in the immunohistochemical expression of these molecules, and the neuroprotective benefit of L-Arg may be attributed to preventing neural cell necrosis. Copyright (C) 2005 S. Karger AG, Basel.Öğe Effects of melatonin administration on intestinal adaptive response after massive bowel resection in rats(Springer, 2006) Ozturk, H; Öztürk, H; Yagmur, Y; Uzunlar, AKThis study evaluates whether melatonin can improve the structure of the small intestine and enhance adaptation in an experimental model of short bowel syndrome. Thirty Sprague-Dawley rats were divided randomly into three experimental groups of 10 animals each. In one group, only laparotomy was performed and these rats served as the sham-control group (G 1). The remaining 20 rats under-went 90% small bowel resection (SBR) and formed the two experimental groups: the SBR/untreated group (G2), and the SBR/melatonin-treated group (G3). Rats in the SBR/untreated group received no therapeutic treatment. Rats in the SBR/melatonin-treated group received melatonin intraperitoneally for 3 weeks. The animals were weighed daily. All rats underwent relaparotomy on day 21 of the experiment. Remnant small bowel was excised and evaluated for villus height. total mucosal thickness, and crypt cell mitosis. After the 90% SBR, all animals suffered from diarrhea and weight loss between the first and the sixth postoperative days. The body weight of the SBR/melatonin group showed significant increases at the beginning of postoperative day 10 and day 21 in comparison to that of the SBR/untreated group. The rats treated with melatonin had significantly greater villus height and crypt cell mitosis compared to the sham-control group and the SBR/untreated group. In addition, the mucosal thickness was significantly increased in the SBR/melatonin-treated group compared to the SBR/untreated rats. These observations suggest that melatonin treatment increases villus height, total mucosal thickness, and crypt cell mitosis after massive SBR and it may exert a considerable effect oil the mucosal adaptive response in short bowel syndrome in rats.Öğe The effects of mibefradil, a T-type Ca2+ channels blocker, on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney(Taylor & Francis Ltd, 2005) Gezici, A; Ozturk, H; Ozturk, HThis study was designed to determine the possible protective effect of mibefradil on renal ischemia/reperfusion (I/R) injury. Unilaterally nephrectomized Sprague-Dawley rats were subjected to 60 min of left renal ischemia followed by 45 min of reperfusion. Group 1 were sham-operated animals; group 2, I/R/untreated animals; and group III, I/R/ mibefradil-treated animals. A 99mTc-DTPA scan was taken to measure kidney perfusion, glomerular filtration rate (GFR) and the time elapsed from isotope injection to the maximum of the curve. Serum creatinine, blood urea nitrogen ( BUN), kidney malondialdehyde (MDA) level were determined as well as examining the kidneys histologically. Treatment of rats with mibefradil produced a significant reduction in the serum levels of creatinine and urea nitrogen. T-max-sec ( renal perfusion) was significantly lower in group 2 than in groups 1 and 3. The GFR was markedly greater in group 3 than in the group 2. The Tmax-min was significantly greater in group 2 than in group 3. Mibefradil treatment significantly decreased the MDA levels. The histopathologic score was significantly less in the group 3 rats compared with group 2 rats. Kidneys of group 2 rats showed tubular cell swelling, cellular vacuolization, pyknotic nuclei, medullary congestion, and moderate to severe necrosis. Treatment with mibefradil preserved the normal morphology of the kidney and shows normal glomeruli and slight edema of the tubular cells. These findings suggest that mibefradil reduces the renal dysfunction associated with I/R of the kidney.Öğe The effects of nitric oxide on the expression of cell adhesion molecules (ICAM-1, UEA-1, and tenascin) in rats with unilateral testicular torsion(W B Saunders Co, 2003) Ozturk, H; Buyukbayram, H; Ozdemir, E; Ketani, A; Gurel, A; Onen, A; Otçu, SBackground/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 11, 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 11, 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 totted testicular tissue may be a pathophysiologic sign of inflammation. NO regulates adhesion molecules expression.Öğe Esophageal, tracheal and pulmonary parenchymal alterations in experimental esophageal atresia and tracheoesophageal fistula - A histological and morphometric study(Karger, 2002) Otcu, S; Kaya, M; Ozturk, H; Buyukbayram, H; Dokucu, AI; Onen, A; Yucesan, SPulmonary complications are among the most important causes of morbidity and mortality in neonates with esophageal atresia and tracheofistula. We aimed to investigate the possible causes of respiratory complications encountered in esophageal atresia (EA) and tracheoesophageal fistula (TEF) in an experimental model. Sprague-Dawley fetal rats treated with adriamycin were used for the experiment. Time mated pregnant rats were given 1.75 mg/kg of adriamicyn intraperitoneally on days 6-9 of gestation. The fetuses were sacrified on day 21, weighed, and dissected under the surgical microscope. The animals were divided into four groups: (1) control group; (2) saline-injected group; (3) adriamycin-induced EA group, and (4) adriamycin administered but without development of EA. The lungs, esophagus, and trachea were excised and underwent histological examination. The mucosa of distal esophagus was thickened (p < 0.05); the submucosa was thinner (p < 0.05); and the muscular layer was thickened (p < 0.05) in fetuses with EA and TEF. In adriamycin-treated rats, in which EA and TEF developed, tracheal cartilage was loosened and formed into a D or C shape. The cartilage was fragmented into several segments on transverse sections in most fetuses. Alveolar septa were thin in lungs of fetus with EA and TEF (p < 0.05), without any fibrosis or evidence of parenchymal abnormality microscopically. Our findings suggest that respiratory complications may contribute to structural lesions in the trachea and particularly in the distal esophagus but not in the pulmonary parenchyma itself. Copyright (C) 2002 S. Karger AG, Basel.Öğe Expression of CD44 and E-cadherin cell adhesion molecules in hypertrophied bladders during chronic partial urethral obstruction and after release of partial obstruction in rats(Elsevier Science Inc, 2005) Ozturk, H; Ozturk, H; Guneli, E; Yagmur, Y; Buyukbayram, HObjectives. To determine the functional changes in the bladder and the expression of adhesion molecules in bladder tissue during chronic partial urethral obstruction and after release of partial obstruction in rats. Methods. Twenty-one male Sprague-Dawley rats were separated into three groups, each containing 7 rats. A sham operation was performed in group 1 and cystometry was done 6 weeks later. In groups 2 and 3, hypertrophied unstable bladders were developed by partial infravesical outflow obstruction during a 6-week period. After this period, cystometry was performed in all group 2 rats. In group 3, the ligature was removed, the rats were followed up for 6 weeks, and then cystometry was performed. After cystometric evaluation, the bladders in all the rats were removed, weighed, and studied immunohistopathologically. Results. After release of infravesical outflow obstruction, the bladder weight, residual volume, bladder capacity, maximal voiding pressure, voiding amplitude, and bladder contraction time decreased and bladder compliance increased in group 3 compared with group 2. CD44 and E-cadherin expression in the interstitial space and uroepithelial bladder tissue in group 2 rats stained intensely compared with those of groups 1 and 3. Conclusions. After release of 6 weeks of infravesical outflow obstruction, the cystometric parameters were significantly improved. Expression of CD44 and E-cadherin in the obstructed bladder tissue may be a pathologic sign of inflammation.(c) 2005 Elsevier Inc.Öğe Influence of the platelet-activating factor receptor antagonist BB-882 on intra-abdominal adhesion formation in rats(Karger, 2003) Otcu, S; Ozturk, H; Aldemir, M; Kilinc, N; Dokucu, AIPostoperative intra-abdominal adhesion formation is a major clinical problem. We aimed to examine the preventive effect of treatment with the platelet-activating factor (PAF) antagonist (lexipafant, BB-882) on experimentally induced intra-abdominal adhesion formation in rats. Twenty male Sprague-Dawley rats weighing 250 and 290 g were studied. Generation of adhesions in rats by brushing a 1-cm(2) area of the cecum and the peritoneum on the right side of the abdominal wall was followed by intra-abdominal administration of saline and 5 mg/kg in a volume of 0.2 ml PAF receptor antagonist BB-882. After 45 days, formation of adhesions was graded and histological evaluation was processed. The severity of adhesions was significantly less in the BB-882 group than in the control group (p < 0.001, p < 0.05). The average adhesion scores in the control and BB-882 groups were 3.2 +/- 0.6 and 0.6 +/- 0.6, respectively, and the difference between both groups was found to be significant (p < 0.0001). The number of polymorphonuclear leukocytes and fibrotic areas was significantly decreased in the BB-882 group when compared to the control group (p < 0.001, p < 0.002). In conclusion, this study confirms the efficacy of BB-882 in the prevention of postoperative intra-abdominal adhesions in a rat model. Copyright (C) 2003 S. Karger AG, Basel.Öğe Non-operative management of isolated solid organ injuries due to blunt abdominal trauma in children(Georg Thieme Verlag Kg, 2004) Ozturk, H; Dokucu, AI; Onen, A; Otçu, S; Gedik, S; Azal, OFThe purpose of this study was to evaluate essential prerequisites for a selective non-operative approach in children with solid organ injuries due to blunt abdominal trauma, and to determine the predictive value of two different trauma scoring systems: the Injury Severity Score (ISS) and the Paediatric Trauma Score (PTS). A retrospective review of children who were admitted with blunt abdominal solid organ injuries to a paediatric trauma Centre between January 1986 and September 2001 was performed. Hepatic, splenic, and renal injuries were graded, based on the American Association for the Surgery of Trauma (AAST) Organ Injury Scale (ranged from grade I to IV). The patients were treated non-operatively or operatively and the two groups were compared for variables such as age, blood transfusion, ISS, PTS, length of hospitalisation, morbidity and mortality rate. Two hundred and five patients (147 boys and 58 girls) entered in this study. Median age was 7 years (1 - 15 yrs). The most common cause of trauma was falls (50%). Abdominal organ injuries were present in all patients with the spleen as the most commonly injured organ (111 patients). Fifty-one patients (32%) had additional extra-abdominal organ injuries. Thirty-five (17%) patients were treated operatively, while 170 (83%) were treated non-operatively. Post-traumatic complications developed in 10 patients treated operatively versus 4 patients treated non-operatively. Four patients died due to multiple organ failure (2 non-operative, 2 operative). When compared to the non-operative group, higher transfusion requirements (p < 0.05), a higher ISS (p < 0.01), lower PTS values (p = 0.0001), a longer hospitalisation period (p = 0.0001), and a higher complication rate (p < 0.05) were observed in the operative group. in addition, the non-operative treatment approach was more common in the last five years compared to the previous ten years (p = 0.002). In conclusion, the appropriate non-operative management of injured children reduces the risks of blood transfusion and decreases the length of hospital stay compared with a surgical approach. The use of physiological parameters and radiological findings may be sufficient criteria for observing haemodynamically stable patients with isolated abdominal organ injuries, and thus intensive care unit costs may be avoided. In addition, a careful and close follow-up is essential in injured patients with a low PTS or high ISS.Öğe PAF antagonist BN-52021 reduces intercellular adhesion molecule-1 expression and oxidative stress in rats with reperfusion damage due to unilateral testicular torsion(Springer, 2006) Ozturk, H; Ozturk, H; Yagmur, YThe aim of this study was to determine the effects of specific platelet-activating factor (PAF) antagonist BN-52021 on intercellular adhesion molecule-1 (ICAM) expression and oxidative stress in rats with reperfusion damage due to unilateral testicular torsion. Thirty male Sprague-Dawley rats were separated into three groups, each containing ten rats. A sham operation was performed in group 1 (control). In group 2 [ischemia-reperfusion (I-R)/untreated], 1-h detorsion of the testis was performed after 6 h of unilateral testicular torsion. In group 3 (I-R/BN-52021), after performing the same surgical procedures as in groups II, BN-52021 was given intravenously at the starting time of reperfusion. In all experimental rats, ipsilateral orchiectomies were performed for histological examination and measuring the tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). MDA values and the testicular injury score decreased and SOD, CAT and GSH-Px values increased in the I-R/BN-52021 treated group compared to in the I-R/untreated group. Most of the specimens in the I-R/BN-52021 treated group showed grade-I testicular injury. However, the injuries in the I-R/untreated rats varied between grades III and IV. An ICAM-1 expression was intensive in the interstitial spaces and basement membrane of the tubuli seminiferi, of testicular tissue in the I-R/untreated group. However, an ICAM-1 expression was mild in the I-R/BN-52021 group. BN-52021 may play an important role in the immunohistochemical expression of adhesion molecule ICAM-1 and may reduce oxidative stress in rats with reperfusion damage due to unilateral testicular torsion.Öğe Protective effects of recombinant human interleukin-4 administration on the hypoxia-reoxygenation-induced gastric and intestinal injury in rat pups(Taylor & Francis Inc, 2005) Ozturk, H; Ozturk, H; Buyukbayram, HA total of 40 rat pups were randomly divided into 4 groups. Group 1 (sham) rats served as nonhypoxic controls. Group 2 (rhIL-4 treated/control) rats were subjected to H-O and were then returned to 3 hypoxia-reoxygenation [H-O]/untreated) rats were subjected to H-O and were then returned to their mothers. Group 4 (H-O/rhIL-4 treated) rats were subjected to H/O and were treated with rhIL-4 for the next 3 days. All animals were killed on day 4 and gastric and intestional specimens were obtained to determine the tissue level of malondialdehyde (MDA) and histological changes. In group 3 MDA levels were significantly increased compared with groups 1,2, and 4. In group 4, MDA levels were not significantly different compared with group 3. The gastric and intestinal injury score were significantly group 3 and 4 rats compared with group 1 and 2. However this increase was lower in. group 4 rats compared with group 3. In group 3, after hypoxia following reoxygenation, exfoliation and necrosis of superficial cells, blood cell infiltratian, and structural alterations on the two-third parts of the glandular pits, and bleeding erosions developed in all stomachs. Treatment with rhIL-4 produced a reduction of exfoliation of superficial cells, hemorrhage, and blood cell infiltration. In group 3 animals, destruction of villi and crypts of ileum and in some cases extension to the muscularis were noticed. In contrast, in the rats treated with rhIL-4, lesions were, limited essentially to the very tips of the villi. This study found beneficial effects of rhlL-4 in an experimental model of hypoxio-induced gastric and intestinalal injury.Öğe Relation between severity of injury and the early activation of interleukins in multiple-injured patients(Karger, 2005) Yagmur, Y; Ozturk, H; Unaldi, M; Gedik, EThe aim of this study was to evaluate the relation between severity of injury and the early activation of interleukins in multiple-injured patients. Ninety-nine patients with multiple injuries were included in this prospective study. Plasma levels of interleukin (IL)-1, IL-2, IL-6, IL-8 and TNF-alpha were measured. Injury Severity Score ( ISS), Revised Trauma Score (RTS), Glasgow Coma Score (GCS) and the Acute Physiology and Chronic Health Evaluation II (APACHE- II) were all recorded. Of the 99 patients, 82 were male and 17 were female. The mean age was 26.6 +/- 20.7 years. The mortality rate for this series was 17%. Patients who died from trauma exhibited a significant increase for IL-2, IL-6 and IL-8 in comparison with patients who survived. Significant differences for ISS, RTS and GCS were found between survivors and non-survivors. Values in all patients with ISS 1 16 were increased and these increases were significant for IL-6 and IL-2. These data show that the initial increase of IL-2, IL-6 and IL-8 might predict the patients with a high possibility of mortality and a significant increase of IL-2 and IL-6 in patients with ISS > 16 might be used in a new developed trauma score combined with ISS as an indicator for the injury severity. Copyright (C) 2005 S. Karger AG, Basel.
