Ahmet Kazez

Hypoxia-induced necrotizing enterocolitis in the immature rat: The role of lipid peroxidation and management by vitamin E

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.

Protective Effect of Melatonin on Antioxidative System in Experimental Ischemia-Reperfusion of Rat Small Intestine

Aims: Effect of exogenously administered melatonin (N-acetyl 5-methoxytryptamine) on antioxidant systems in experimental Ischemia–Reperfusion (I-R) of rat gastrointestinal system (GIS) was examined.Methods: A total of 40 rats were divided into 4 groups: Group 1 (Sham), Group 2 (I-R), Group 3 (I-R + 10 mg/kg melatonin) and Group 4 (I-R + 20 mg/kg melatonin). Activity levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined in small intestines.Results: There was a significant (p<0.05) reduction in GSH-Px levels in Group 2 (64.16±7.02 U/mg protein) compared to Group 1 (80.15±9.32 U/mg protein). We observed a meaningful increase in GSH-Px levels in melatonin applied groups (Group 3: 75.94±9.83 U/mg protein, Group 4: 78.55±9.11 U/mg protein) compared to Group 2. Correspondingly, SOD activity levels were significantly reduced (p<0.001) in Group 2 (24.14±4.35 U/mg protein) compared to controls (52.91±6.13 U/mg protein). A stronger effect (p<0.001) of melatonin was observed on SOD levels compared to GSH-Px levels in both doses (Group 3: 38.96±6.39 U/mg protein, Group 4: 43.07±7.76 U/mg protein). Levels of selenium were reduced significantly in Group 2 (1.11±0.31 μg/g tissue) compared to Group 1 (2.01±0.19 μg/g tissue). Melatonin application in Group 3 (1.13±0.28 μg/g tissue) and Group 4 (1.89±0.48 μg/g tissue) caused an increase in selenium levels. There was a strong correlation between increases in selenium and GSH-Px levels in Group 4 (r:0.651 p<0.01).Conclusions: Melatonin seems to exert its antioxidant effect in GIS tract by stimulating SOD and GSH-Px. Selenium also seems to have an antioxidant contribution on protecting rat gastrointestinal tract I-R injury.

Ectopic adrenal tissue in the inguinal region in children.

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.

Giant Mesenteric Lipoma as a Rare Cause of Ileus in a Child : Report of a Case

Mesenteric lipoma is a rare benign tumor of mature fat cells. Although generally asymptomatic, it occasionally causes abdominal pain, ileus, and small bowel volvulus, depending on its location and size. A definitive diagnosis can be made by pathological examination. Ultrasonography and abdominal computed tomography show this lesion as a well-defined, homogeneous mass with fat density surrounded by a thin capsule. Because of its rare etiologic origin, we report the case of a 7-year-old girl with a mass in the abdomen and ileus, found to be caused by a mesenteric lipoma.

Neurofibroma of the breast in a boy with neurofibromatosis type 1

Neurofibromas occurring in the breast are very rare. A 10-year-old boy with neurofibromatosis type 1 (NF1) presented with a palpable mass on his left breast. US showed a well-defined and hypoechoic solid mass within the subcutaneous fat tissue in the areolar area. Mass was isointense compared to muscle and hypointense compared to fat tissue on TIW and T2W MR images. Excisional biopsy was applied to the mass. The diagnosis of gynecomastia and neurofibroma was made on the basis of histopathological and immunohistochemical findings.

The effect of vitamin E on ipsilateral and contralateral testis following unilateral testicular torsion in rats.

An experimental study was conducted to investigate the role of lipid peroxidation in ipsilateral and contralateral testicular reperfusion injury following unilateral testicular torsion (TT) and the effect of vitamin E in the management of this injury. Fifty adult male Sprague-Dawley rats were divided into five equal groups. Bilateral orchiectomy was performed immediately in group 1, and 3 h after unilateral TT in group 2. In group 3, both testes were harvested 3 h after a sham operation. In groups 4 and 5, unilateral TT, detorsion after 3 h and bilateral orchiectomy after 6 h were performed. Vitamin E was given before detorsion in group 4 and after detorsion in group 5. The levels of malondialdehyde (MDA) were meas-ured as an index of lipid peroxidation in all testes. There were no significant differences between right and left testes within groups or between right or left testicular MDA values in different groups. The results suggest that lipid peroxidation does not play an important role in ipsilateral and contralateral testicular injury following unilateral TT and that vitamin E given before or after detorsion of testes is not useful in preventing testicular reperfusion injury.

A model of hypoxia-induced necrotizing enterocolitis: The role of distension

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.

Irisin immunohistochemistry in gastrointestinal system cancers

Cancer is the leading cause of morbidity and mortality worldwide. Some studies have shown that high heat kills cancer cells. Irisin is a protein involved in heat production by converting white into brown adipose tissue, but there is no information about how its expression changes in cancerous tissues. We used irisin antibody immunohistochemistry to investigate changes in irisin expression in gastrointestinal cancers compared to normal tissues. Irisin was found in human brain neuroglial cells, esophageal epithelial cells, esophageal epidermoid carcinoma, esophageal adenocarcinoma and neuroendocrine esophageal carcinoma, gastric glands, gastric adenosquamous carcinoma, gastric neuroendocrine carcinoma, gastric signet ring cell carcinoma, neutrophils in vascular tissues, intestinal glands of colon, colon adenocarcinoma, mucinous colon adenocarcinoma, hepatocytes, hepatocellular carcinoma, islets of Langerhans, exocrine pancreas, acinar cells and interlobular and interlobular ducts of normal pancreas, pancreatic ductal adenocarcinoma, and intra- and interlobular ducts of cancerous pancreatic tissue. Histoscores (area × intensity) indicated that irisin was increased significantly in gastrointestinal cancer tissues, except liver cancers. Our findings suggest that the relation of irisin to cancer warrants further investigation.

Hepatic Pseudocyst as a Result of Ventriculoperitoneal Shunts: Case Report and Review of the Literature

Hepatic pseudocyst formation is a rare intra-abdominal complication of ventriculoperitoneal shunts. The presence of an intracranial tumor and a history of central nervous system infection are major risk factors for the development of this complication. Hepatic pseudocysts secondary to ventriculoperitoneal shunts can be classified as intra- and extra-axially growing cysts. On abdominal computed tomography images, extra-axially growing pseudocysts are typically surrounded by a fine annulus that shows continuity to hepatic parenchyma. For treatment of extra-axially growing hepatic pseudocysts, surgical unroofing of the cyst and repositioning of the catheter is an effective method if there is no shunt infection and/or dysfunction.

Detection of bacterial translocation during intestinal distension in rats using the polymerase chain reaction

Abstract. To investigate whether distension causes bacterial translocation (BT), a rat model reported earlier by us was used and to detect the presence of bacterial DNA in blood by polymerase chain reaction (PCR) assay, the most sensitive detection method to date. In 4 groups of 4-week-old Wistar-albino rats a total of 15 animals each were included. In the 1st group (distension+gavage), 1010 Escherichia coli colonies were given via gavage and distension was carried out by rectal air inoculation. In the 2nd group (gavage), animals were inoculated with E. coli and no distension was induced. The 3rd group (distension) were only distended and no bacteria were inoculated. The control group were neither distended nor inoculated with E. coli. Blood samples were collected 3 h after manipulations and both blood cultures and PCR assays were performed. According to the PCR results BT was evident in 80% of group 1, 20% of group 2, and 33% of group 3 animals. BT was not determined in the control group. Significantly low percentages of positivity were observed in blood cultures in all groups (P < 0.05). These results confirm reports that BT occurs in the presence of distension and that PCR is a superior way of determining BT. Thus, it would be advisable to utilize PCR technology in cases where the possibility of distension exists, as early intervention might be useful before any severe clinical pathology (sepsis, multiple-organ-system failure) becomes evident.