Hamit Okur
Erciyes University
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Featured researches published by Hamit Okur.
Journal of Pediatric Surgery | 1995
Hamit Okur; Mustafa Küçükaydin; Kader Köse; Olgun Kontas; Pakize Doǧan; Ahmet Kazez
The authors developed an experimental model of necrotizing enterocolitis (NEC) by hypoxia-reoxygenation, and determined the content of malondialdehyde levels as an index of lipid peroxidation, related with a free-radical reaction in the gastrointestinal tract of newborn rats. They also investigated the role of vitamin E, an antioxidant, in this free-radical injury. The study was performed on 1-day-old rats. The 30 rat pups were divided into three groups. Hypoxia was induced by placing the pups in a 100% carbon dioxide chamber for 5 minutes. The pups were reoxygenated with 100% oxygen for 5 minutes. Group 1 (n = 10) was subjected to hypoxia-reoxygenation and killed 3 days after hypoxia. Group 2 (n = 10) was subjected to hypoxia-reoxygenation and treated with vitamin E (30 IU/kg/d intraperitoneally) for the next 3 days, and killed. Group 3 (n = 10) rats served as controls. The histopathology of the intestinal lesions in group 1 animals was characteristic of ischemic injury and ranged from superficial epithelial damage with villous shortening to transmural necrosis. In the vitamin E-treated animals these lesions were milder. The malondialdehyde levels of group 1 were significantly higher than those of the other two groups (P < .001). This study shows that oxidant-mediated lipid peroxidation injury plays a central role in mediating hypoxia-induced intestinal necrosis and suggests that vitamin E may play a therapeutic role in NEC.
Pediatric Pathology & Laboratory Medicine | 1995
Hamit Okur; Mustafa Küçükaydin; Ahmet Kazez; Olgun Kontas
Adrenal rests are common in children and are most often found as bright yellow, retroperitoneal nodules from the diaphragm to the pelvis. They are usually incidental findings during surgery. In a 12-month period, 268 children, 18 days to 15 years (mean 3.2 years) of age, underwent 304 operations for common inguinoscrotal disorders at the Department of Pediatric Surgery, Erciyes University Medical School. There were 252 males and 16 females, (M/F 15.7:1). Ectopic adrenal tissue was found in nine males (3%). This report concerns the incidence and structure of aberrant adrenal tissue found in children during inguinoscrotal operations, including its embryology, histology, and clinical implications.
Pediatrics International | 2009
Cigdem Ulukaya Durakbasa; Hamit Okur; Huseyin Murat Mutus; Ahmet Yagmur Bas; Mehmet Ali Ozen; Varol Sehiralti; Ahmet Nadir Tosyali; Itır Ebru Zemheri
Background: The present study gathers a single institutional experience of symptomatic omphalomesenteric duct (OMD) remnants in children with an emphasis on the age and modes of presentation, the surgical intervention and the histopathological findings.
Pediatric Surgery International | 2000
Cüneyt Turan; Uğur Özkan; Bülent Hayri Özokutan; Musa Özdemir; Hamit Okur; Mustafa Küçükaydin
Abstract To evaluate the morbidity and mortality of corrosive esophageal injuries (CEI) in the neonatal period, the records of 184 children hospitalized following caustic ingestion over a 10-year period from January 1987 to November 1997 were reviewed. Eight (4.3%) were newborns (5 boys and 3 girls). The mean age of the newborns was 12 days (range 1–28). The ingested caustic materials were benzalkonium chloride in six patients and trichloroacetic acid in two. Oropharyngeal examination and esophagoscopy were performed for diagnosis. Hyperemia and fibrin plaques were present in the oropharynx in all patients. The management consisted of endotracheal intubation, antibiotics, corticosteroids, and total parenteral nutrition. Pneumonia and sepsis developed in three patients and one died of sepsis. Stenosis developed in two patients, who were treated three times with antegrade dilatations. The morbidity was 62.5% (five patients) and the mortality was 12.5% (one) in newborns with CEI. These results indicate that ingestion of a caustic substance results in high morbidity and mortality in newborns. Parents and nurses should be warned about this risk.
Journal of Pediatric Surgery | 1997
Ahmet Kazez; Nursel Küçükaydin; Mustafa Küçükaydin; Olgun Kontas; Hamit Okur; Pakize Dogan
BACKGROUND/PURPOSE This study was performed to investigate additional effects of intestinal distension in the damage to the gut caused by hypoxia-reperfusion. METHODS Five groups each consisting of ten 1-day-old Wistar albino rat pups were studied; Group 1, hypoxia-reoxygenation; Group 2, hypoxia-reoxygenation and distension; Group 3, distension and hypoxia-reoxygenation; Group 4, distension; and Group 5, control. Hypoxia was induced by placing the rat pups in a 100% carbon dioxide chamber for 5 minutes. After the hypoxia, the pups were exposed to 100% oxygen for reoxygenation for 5 minutes. The intestinal distension was carried out with a fine 21-gauge SILASTIC cannula via rectal route. The rats were killed on the third day, and all the intestine were harvested from duodenum to sigmoid colon. Malondialdehyde (MDA) levels were determined as an index of lipid peroxidation related to free radical reaction in the intestine. The histopathologic investigation was carried out by light microscopy in a blinded fashion. RESULTS The MDA levels of Group 3 animals were significantly higher than those in Group 1, 4, and the control group (P < .05). The MDA level of Group 2 did not differ significantly from that of the Group 3 (P > .05). All MDA levels of the study groups also were significantly higher than the control group (P < .05). CONCLUSION The results demonstrated that intestinal distension increased the damaging effects of hypoxia-reoxygenation in the gut.
Regulatory Peptides | 2005
Zübeyde Gündüz; Nurcan Dursun; Hülya Akgün; Figen Öztürk; Hamit Okur; Nedret Koç
BACKGROUND Leptin has direct and indirect effects on renal pathophysiological characteristics. In the present study, the effects of long-term leptin infusion on the renal hemodynamics, renal excretory functions, and the expression of transforming growth factor-beta (TGF-beta), plasma endothelin-1 (ET-1) levels, and preventive effects of the angiotensin II type 1 receptor antagonist, losartan, on these renal changes were evaluated. METHODS The study was performed by using forty Wistar albino rats. On day 0, osmotic mini-pumps filled with leptin or placebo were intraperitoneally placed under sterile conditions. The rats in Group L (Leptin group, n=15) and Group LL (Leptin-losartan group, n=15) were given recombinant murine leptin at a rate of 250 ng per hour for 28 days. Control rats (Group C, n=10) were administered placebo at the same infusion rate. The rats in Group LL were also administered losartan (10 mg kg(-1) d(-1)) perorally for 28 days. On day 28, the rats were placed in metabolic cages, and the food and water intakes were determined, and the urine was collected for 24 h. At the end of the study, systolic blood pressure (SBP), diastolic blood pressure (DBP) were determined directly from the left femoral artery, and renal blood flow (RBF) was recorded indirectly using a laser Doppler flow module. RESULTS Leptin infusion did not produce any changes in systemic arterial blood pressures and urinary flow rate. The rates of creatinine (Cr), sodium (Na), and protein excretions of the animals infused leptin were significantly increased. The urinary Cr and Na excretions were decreased, while the urinary protein excretion was normalized with the losartan treatment. The rats infused leptin had also higher circulating ET-1 levels. ET-1 levels were also reversed to the normal values with the losartan treatment. Renal TGF-beta1 expression was determined immunohistochemically, and it was more prominent in the renal tubules from the rats treated with leptin. The losartan treatment had no effect on renal TGF-beta1 expression. CONCLUSIONS Our results indicate that pathophysiological increases in plasma leptin concentrations cause enhanced renal Na, Cr and protein excretions, and high circulating ET-1 levels. Na and Cr excretions were decreased, while proteinuria and plasma ET-1 levels were normalized by losartan treatment, suggesting that renin-angiotensin system activation may have a role in leptin induced renal changes. TGF-beta1 may have an important role in leptin induced nephropathy.
Pediatric Surgery International | 1998
Mustafa Küçükaydin; Bülent Hayri Özokutan; Cüneyt Turan; Hamit Okur; Özkan Köse
Abstract During a 6-year period, 312 boys (mean age 4.7 years) underwent orchidopexy for cryptorchidism. A total of 388 epididymides were examined and the configurations were recorded as a prospective trial. This study consists of 166 ectopic testes and 222 undescended testes. The observed configurations of epididymides in the ectopic testes were: type 1a in 99 cases (59.6%), type 1b in 35 (21.1%), type 2 in 24 (14.5%), type 3 in 7 (4.2%), and type 4 in 1 (0.6%). There were no patients in the study with type 5 and 6 anomalies. The configurations of epididymides in the undescended testes were: type 1a in 105 (47.3%), type 1b in 63 (28.4%), type 2 in 26 (11.7%), type 3 in 13 (5.9%), type 4 in 5 (2.3%), type 5 in 7 (3.2%), and type 6 in 3 (1.4%).The data revealed that the incidence of epididymal abnormalities in undescended testes (41%) was higher than that in the ectopic testes (25.9%) (P < 0.05).
Urology | 2003
Hamit Okur; D.C.S. Gough
OBJECTIVES To describe the presentation and radiologic investigation of 6 patients who had persistent müllerian duct remnants (MDRs) in association with severe hypospadias and to review the long-term results of surgical management using the transtrigonal approach. METHODS The hospital records of 6 patients who had MDRs and who underwent transvesical transtrigonal excision were reviewed and long-term assessment of urinary control and continence was made by interview. RESULTS One patient presented in the newborn period with clinically palpable MDRs and five others escaped detection until after the hypospadias repair, despite ultrasonography of the pelvis specifically looking for MDRs. All had undescended testis with severe hypospadias. The karyotype was 45XO/46XY in five and 46XY in one. The most consistently useful examinations were voiding cystourethrography and magnetic resonance imaging. The excision was transtrigonal in each case. Early or late postoperative complications were not encountered in any of our patients. Gonadal histologic examination showed streak gonad in four and a dysgenetic testis in one. Histopathologic examination showed rudimentary uterus and fallopian tubes in 4 patients and a cystic structure lined with squamous and columnar epithelium in 2 patients. No areas of metaplasia were noted. Bladder emptying was normal after surgery. CONCLUSIONS Ultrasound examination alone is not always sufficient to diagnose MDRs, which may be responsible for symptoms after hypospadias surgery. The transtrigonal approach provided excellent visualization and access to MDRs and prostatic urethra.
The Annals of Thoracic Surgery | 1996
Hamit Okur; Mustafa Küçükaydin; Adnan Öztürk; Suleyman Balkanli; Ali Bozkurt
Bronchogenic cysts are relatively uncommon congenital lesions. Because of the variability in clinical presentation and the shortcomings of diagnostic procedures, bronchogenic cysts present a diagnostic problem. This report describes a giant bronchogenic cyst that presented as a lobar emphysema in a newborn.
Urologia Internationalis | 2006
Hamit Okur; Sabahattin Muhtaroglu; Ali Bozkurt; Olgun Kontas; Nursel Küçükaydin; Mustafa Küçükaydin
Introduction: To investigate the effects of blocking prenatal androgen with the anti-androgen flutamide on testicular weight (TW), seminiferous tubular diameter (STD), testicular biopsy score (TBS), testicular testosterone (TT), and fertility. Materials and Methods: Ten pregnant Wistar albino rats were injected with flutamide (100 mg/kg) on gestational days 16 and 19. Rats injected with the solvent were used as controls. Male pups from these dams were evaluated for testicular descent on postnatal day 22. The ability of each male to produce offspring was tested when the animals were aged 130 days. The rats were killed when 180 days old, and the testes were removed. Results: Sixteen of the 24 male rats (66.6%) exhibited cryptorchidism (6 unilateral, 10 bilateral) in the flutamide-treated group. Three of the rats with normally descended testicles were fertile, but none of the cryptorchid rats was fertile in flutamide-treated group. The average TW, mean STD, TBS and TT levels of the flutamide-treated rats was significantly lower than in the solvent-injected rats. However, there was no significant difference in these values between descended and undescended testes in flutamide-treated rats. Conclusion: Blocking of prenatal androgen with flutamide interferes with testicular development by inhibiting testicular descent, and also effects testicular morphology and function in both the descended and undescended testes of rats.