Serdar Erkasap
Eskişehir Osmangazi University
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Featured researches published by Serdar Erkasap.
Toxicology | 2003
Ahmet Kahraman; Nilüfer Erkasap; Tulay Koken; Mustafa Serteser; Serdar Erkasap
The role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effects of quercetin were evaluated in an experimental model. In addition, the effects of quercetin on gastric damage were evaluated histopathologically. Rats were divided into three groups as control rats, ethanol treated rats and ethanol+quercetin treated rats. Ethanol group was given a gastric gavage containing 1 ml of 80% ethanol (v/v) prepared in distilled water. Quercetin (200 mg/kg body wt.) was given by intragastric gavage 120 min before the administration of ethanol. Gastric tissue thiobarbituric acid reactive substance levels, carbonyl compounds, histamine levels and myeloperoxidase activities were found to be increased in ethanol treated rats and quercetin treatment reversed these increases. No statistically significant changes were found between all groups in catalase activity. The superoxide dismutase activity dropped significantly after ethanol treatment and quercetin treatment increased this enzyme activity. Gastric damage was confirmed histomorphometrically by significant increases in the number of mast cells and gastric erosions in ethanol treated rats. It was also confirmed that quercetin treatment significantly decreased the number of mast cells and reduced the area of gastric erosions. The results suggest that the gastroprotective effect of quercetin in this experimental model could be due to its antiperoxidative, antioxidant and antihistaminic effects.
Hpb | 2004
Sezgin Yilmaz; Ersin Ates; Çiğdem Tokyol; Turan Pehlivan; Serdar Erkasap; Tulay Koken
BACKGROUND Besides its haematopoietic effect, erythropoietin (EPO) has multiple protective effects, i.e. antiapoptotic, antioxidant and angiogenic properties. The neuroprotective effects of EPO against ischaemia have all been demonstrated in cell culture and animal models. The aim of the study was to evaluate the effect of erythropoietin on ischaemia-reperfusion injury (I/R injury) of the liver. METHODS Forty-eight adult male Sprague-Dawley rats weighing 250-300 g were divided into three groups: group I, hepatic ischaemia-reperfusion (Hepatic I/R); group II, hepatic ischaemia-reperfusion + EPO (Hepatic I/R+ EPO); group III, sham. Hepatic ischaemia was created by placing a microvascular clamp on the hepatic pedicle for 45 minutes. EPO was given to group II at a dose of 1000 U/kg 120 minutes before the onset of the ischaemia. Blood samples and liver tissues were obtained after 45 minutes of reperfusion from half of the rats in each group. The remaining rats were killed after a 24-hour observation period and blood and tissue samples were obtained. Blood alanine aminotransferase, tumour necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2) and liver tissue malondialdehyde (MDA) levels were determined. Liver tissue histopathology was also evaluated by light microscopy. RESULTS In rats with hepatic ischaemia, serum levels of ALT, TNF-alpha, IL-2 and liver tissue levels of MDA were reduced by the administration of erythropoietin and the histopathological score was also less severe. CONCLUSION This study demonstrates that pre-ischaemic administration of EPO has protective effects on hepatic I/R injury.
Journal of Physiology and Biochemistry | 2004
Serdar Erkasap; Nilüfer Erkasap; Tulay Koken; Ahmet Kahraman; Kubilay Uzuner; Nuray Yazihan; Ersin Ates
Tumor necrosis factor-alfa (TNF-α) has been established as an important mediator in renal ischemia-reperfusion (I/R) injury. Leptin, a product of the ob gene, has been known to exhibit cytoprotective effects on renal tissue, but its effect on renal tissue TNF-α level after renal I/R injury in rats remains unknown. The purpose of the study was to evaluate the effects of leptin on renal tissue TNF-α, malondialdehyde (MDA), protein carbonyls (PCs) and total sulfydryl group (SH) levels, and plasma nitrite levels after renal I/R injury in rats. The animals were divided into three groups: control, I/R and I/R+leptin. Rats were subjected to renal ischemia by clamping the left pedicle for 45 min, and then reperfused for 1 h. The I/R+leptin group was pretreated intraperitoneally with leptin (10 μg/kg) 30 min before the induction of ischemia. Our results indicate that MDA, TNF-α levels, and PCs were significantly higher in the I/R group than those in the control group (p<0.05). The administration of leptin decreased these parameters (p<0.05) significantly. The SH level was observed to significantly decrease after I/R injury when compared to the control group (p<0.05). Leptin treatment significantly increased tissue SH and plasma nitrite levels when compared to the I/R group (p<0.05). Plasma nitrite levels did not change significantly in I/R when compared to the control. These results suggest that leptin could exert a protective effect on I/R induced renal damage by decreasing TNF-α levels and increasing nitrite level.ResumenEl factor de necrosis tumoral alfa (TNF-α) está implicado en la lesión renal tras isquemia y reperfusión (I/R). Dado que se ha observado que la leptina presenta un efecto citoprotector sobre el tejido renal, se estudia en este trabajo el efecto de la hormona sobre el contenido en el tejido renal de TNF-α, malondialdehido (MDA), niveles de grupos carbonilo protéicos (PC) y de los grupos sulfhidrilo total (SH), y el nivel plasmático de nitrito tras lesión renal por isquemia/reperfusión en rata. Los animales se repartían en tres grupos de 8 ejemplares: control, I/R, e I/R+leptina. Las ratas se sometían a una isquemia renal durante 45 minutos con ulterior reperfusión de una hora. A los del grupo I/R+leptina se les había administrado por vía intraperitoneal leptina (10 μg/kg) 30 minutos antes de la inducción de la isquemia. Los resultados indican que el contenido en MDA, TNF-α y PC está significativamente elevado en el grupo I/R respecto del grupo de control (p<0.05), mientras que el de SH se reduce tras la lesión I/R y el nivel de nitrito en el plasma no varía. El tratamiento con leptina anula los incrementos de los niveles renales de TNF-α, MDA y PC y de la disminución de grupos SH en tejido renal e incrementa el nivel de nitritos plasmáticos por isquemia/reperfusión renal. Estos resultados sugieren que la leptina ejerce un efecto protector sobre la lesión renal inducida por isquemia y reperfusión por la disminución de TNF-α y el aumento plasmático de nitrito.
Surgery Today | 2003
Enver İhtiyar; Serap Isiksoy; Cem Algin; Adnan Sahin; Serdar Erkasap; Bekir Yasar
Ectopic thyroid is a rare developmental anomaly. We describe an unusual case of ectopic thyroid tissue found in the gallbladder wall of a 68-year-old man who underwent cholecystectomy for acute cholecystitis. Pathological findings were compatible with ectopic thyroid tissue in the gallbladder wall. This very rare pathology is discussed with a review of the revelant literature.
Journal of Surgical Research | 2011
Enver İhtiyar; N. Fatih Yaşar; Nilüfer Erkasap; Tulay Koken; Murat Tosun; Setenay Oner; Serdar Erkasap
BACKGROUND The aim of this study was to determine the effects of doxycycline on renal ischemia reperfusion (I/R) injury in a rat model of abdominal compartment syndrome (ACS). MATERIALS AND METHODS Forty-two Sprague-Dawley rats were divided into six groups. In the control group (group 1), kidney samples were collected with no manipulation; in the sham group (group 2) induction of ACS was followed by decompression. In groups 3 and 4, 1 cc of saline was administered intraperitoneally (i.p.) during the induction of ACS, and the kidneys were removed 1 and 24h after decompression, respectively. In groups 5 and 6, doxycycline (10mg/kg i.p.) was injected during the induction of ACS, and similarly all tissue samples were removed 1 and 24h after decompression, respectively. MDA, IL-1β, IL-6, TNF-α, MMP-2, and TIMP-1 were studied, and the apoptotic cells were enumerated histopathologically, and apoptosis and bcl-2 expression were assessed immunohistochemically. RESULTS Creatinine, MDA, IL-1β, and IL-6 levels were significantly higher in group 3, 1h after the reperfusion period compared with the control group, and the same parameters were significantly lower in the groups in which doxycycline was administered, 1 hour after decompression. However, there remained no difference between groups at 24h, except IL-1β, which was decreased to even lower values. TNF-α and TIMP-1 levels were not statistically different in all groups. The MMP-2 level was significantly higher in group 4 by 24h, and there remained no difference between groups 1, 2, and 6. In group 6, there were not any apoptotic cells as were observed in the other groups. The number of apoptotic cells and the expression of bcl-2 was significantly less in the groups in which doxycycline was administered. CONCLUSION Doxycycline had protective effects on I/R injury by decreasing apoptosis via reducing the level of pro-inflammatory cytokines, increasing the level of TIMP-1, and inhibiting the activity of MMP-2.
Transplantation | 1996
Ersin Ates; Peeyush Sharma; Serdar Erkasap; David Talbot; Enver İhtiyar; Bekir Yasar; Haluk Kiper
In order to prevent cyclosporine nephrotoxicity in the ischemic kidney, pentoxifylline was used in a rat model. Seventy-two rats were divided into six groups according to treatment after right nephrectomy: Group I was the control, group II was treated with 25 mg/kg cyclosporine, group III underwent renal ischemia for 45 min, group IV was given 25 mg/kg cyclosporine and subjected to renal ischemia, and group V was subjected to renal ischemia and given 45 mg/kg pentoxifylline (repeated at 12, 36, and 48 hr), group VI underwent renal ischemia and was then given both cyclosporine and pentoxifylline. BUN, creatinine, and potassium levels were significantly elevated 24 hr after cyclosporine (group II), ischemia (group III), and cyclosporine and ischemia (group IV). Sodium levels remained unaffected. BUN levels normalized in all but groups III and IV after 48 hr. Creatinine levels normalized in all but group IV after 48 hr. Creatinine clearance fell in all groups and remained low even after 48 hr. Pentoxifylline prevented dramatic rises in BUN and creatinine and levels nearly normalized after 48 hr. It also histologically prevented extensive tissue damage seen after ischemia. In conclusion, pentoxifylline has a protective effect upon the kidney when subjected to cyclosporine in the presence of ischemia.
Journal of Cancer Research and Therapeutics | 2015
Murat Cilekar; Serdar Erkasap; Ülkü Öner; Murat Akici; Evrim Çiftçi; Hayrettin Dizen; Serkan Türel; Ozgu I Kavak; Sezgin Yilmaz
Squamous cell carcinoma (SCC) is a rare type of breast malignancy and little is known about long-term outcome. In the present report, the clinical features, histopathologic findings and postoperative course of a patient with squamous cell carcinoma are described. We have treated a 47-years-old woman who admitted for right breast mass without any discharge, bleeding and pain. The tumor was, 3 × 2 × 1.5 cm in size with central abscess formation. The result of surgical biopsy revealed large cell keratinizing type of SCC. The metastatic work-up studies ruled out any other probable sources of primary tumor. The patient was performed modified radical mastectomy and axillary dissection and received two cycles of chemotherapy. Squamous cell carcinoma of the breast (SCCB) is a rare entity and should be considered in patients with rapidly progressing breast mass. It should also be considered in breast lesions with abscess formation. The initial therapeutic approach should be surgical excision after histopathological diagnosis.
Current Therapeutic Research-clinical and Experimental | 2010
N. Fatih Yaşar; Riza Özdemir; Enver İhtiyar; Nilüfer Erkasap; Tulay Koken; Murat Tosun; Setenay Oner; Serdar Erkasap
BACKGROUND Abdominal compartment syndrome (ACS) refers to organ dysfunction and ischemia resulting from intra-abdominal hypertension (IAH). Ischemia of the gut results in the triggering of a systemic inflammatory response by releasing cytokines which, in turn, causes capillary leakage leading to bowel edema, further increasing intra-abdominal pressure and resulting in a morbid cycle of ischemia and edema. OBJECTIVE The aim of this study was to determine the effects of doxycycline on intestinal ischemia reperfusion (I/R) injury in a rat model of ACS. METHODS Sprague-Dawley rats were divided into 5 equal groups. In groups 1 and 2, saline (1 cc IP) was administered during induction of ACS and intestinal samples were removed at 1 and 24 hours, respectively, after decompression. In groups 3 and 4, doxycycline (10 mg/kg IP) was injected during induction of ACS and, similarly, intestinal samples were removed at 1 and 24 hours after decompression. In the control group (group 5), intestinal samples were collected without induction of ACS. Malon-dialdehyde (MDA), interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, matrix metalloproteinase-2 (MMP-2), and tissue inhibitor of metalloproteinase-1 were studied and the apoptotic cells were enumerated histopathologically. Apoptosis and β-cell lymphoma 2 (βcl-2) expression were assessed immunohistochemically. RESULTS Thirty-five rats were evenly divided into 5 groups of 7 rats each. MDA, IL-1β, IL-6, TNF-α, and MMP-2 levels were significantly higher in group 1 one hour after the reperfusion period compared with the control group (P < 0.001, P < 0.001, P < 0.05, P < 0.001, and P < 0.01, respectively). The same parameters were significantly lower in group 3, in which doxycycline was administered, than in group 1 (P < 0.001, P < 0.05, P < 0.05, P < 0.001, and P < 0.01, respectively). However, there was no significant difference between groups 2 and 4 in the 24th hour (all, P > 0.05). The mean (SD) number of apoptotic cells and the expression of βcl-2 was highest in group 2 at 24 hours after the reperfusion period (92.5 [11.4] and 35.9 [5.0], respectively) and significantly greater than that in group 4 (P < 0.001 and P < 0.05, respectively). CONCLUSION Doxycycline was associated with protective effects against I/R injury through decreasing apoptosis via attenuating the response of proinflammatory cytokines and inhibiting the activity of MMP-2 in this rat model.
Dicle Tıp Dergisi | 2010
Serdar Erkasap; Eda Ozcelik; Sema Uslu; Mehmet Kara; Nilüfer Erkasap
Objectives: Hepatitis C and interferon may trigger autoimmunity. We aimed to investigate the effects of combination treatment of peginterferon alpha (peg-IFN) + ribavirin in patients with chronic hepatitis C (CHC) on thyroid function tests and thyroid auto antibodies. Materials and Methods: The study included 45 outpatients with proven CHC having normal thyroid functions and previously not treated. The patients received combination of Peg-IFN+ribavirin. Values of fT3, fT4, TSH, antitiroglobulin (Anti-Tg) and thyroid peroxidase antibody (Anti-TPO) were measured at initial, fi rst, third and sixth months of treatment. Frequency of thyroid dysfunction was evaluated according to age and gender of patients. Results: Thyroid dysfunction emerged in 15 (%33.3) of 45 patients at the end of the six month of antiviral treatment. Symptomatic thyroid disease was confi rmed in 2 patients.Subclinical hyperthyroidism was determined in four patients (%8.9), and subclinical hypothyroidism in 3 patients (%6.7) at the end of third month.At the end of sixth month; symptomatic hyperthyroidism was observed in one patient (%2.2), subclinical hyperthyroidism in six (%13.3) and subclinical hypothyroidism in 7 patients (%15.6), and symptomatic hypothyroidism was determined in one patient (%2.2).At the end of the sixth month of antiviral treatment; Anti-Tg antibodies were positive in 12 patients (%26.7) and antiTPO in 11 patients (4 male and 7 female) (%24.5). No sig- nifi cant relationship was found between thyroid dysfunction and age, gender and ALT levels of patients (p>0.05). Conclusion: Periodic follow-up examinations should be done for thyroid autoimmunity and thyroid functions in CHC patients receiving combination treatment of PegINF+ribavirin.In adults, urethral foreign body is commonly observed with mental disorder, psychiatric or sexual behavior distursbance. In this paper, we reported a case which electrical cable wire was inserted into the urethra by the husband.Objectives: Dietary high fructose consumption which is closely associated with endothelial dysfunction via insulin resistance has recently increased in developed countries.Insulin resistance has a promoter effect on many meta-bolic disorders such as syndrome X, polycystic ovary syn-drome, Type 2 diabetes mellitus etc. Our aim in this study is to understand the impact of increased fructose intake on metabolisms of glucose, insulin and endothelial dys-function by measuring nitric oxide (NO) and endothelin-1(ET-1) levels in hepatic tissue which is crucial in fructose metabolism. Materials and Methods: We designed an animal study to understand increased fructose intake on hepatic en-dothelium. Twenty adult male albino rats were divided into two groups; the study group (group 1, n=10) received isocaloric fructose enriched diet (fructose-fed rats, con-taining 18.3% protein, 60.3% fructose and 5.2% fat) while the control group received purifi ed regular chow (group 2,n=10) for 2 weeks. After feeding period, blood and hepatictissue samples were collected and glucose, insulin, NO and ET-1 levels were analysed. Results: We found increased fasting glucose and insulin levels and impaired glucose tolerance in fructose fed rats. Higher NO and lower ETn1 levels were also detected in hepatic tissue samples of the group 1. Conclusion: Increased fructose consumption has delete- rious effects on glucose tolerance, insulin resistance and may cause to endothelial dysfunction. Key words: Fructose consumption, endothelial dysfunc-tion, nitric oxide, endothelin-1, liver.Oral squamous cell papilloma is a cutaneus lesions occurring due to human papilloma virus infections. These lesions spread locally and tend to have a high recurrence rate. Cases usually have a slow progression rather than acute symptoms. The course of disease is mostly subclinical. Although there are various treatment modalities which are recommended for the treatment of the disease, there is no particular and effective treatment modality that was proven. Limited surgical excisions result in frequent recurrences due to the presence of HPV in latent form around the lesions. Therefore, surgical excisions are combined with the other treatments such as systemically used interferons. We aimed to present a case of squmous cell papilloma with locally extensive lesions in the oral mucosa. Our patient was managed by the surgical excision and systemically given interferon treatment.
World Journal of Surgical Oncology | 2010
Enver İhtiyar; Özgül Paşaoğlu; Serdar Erkasap; Barış R Karakaş; Fatih Yaşar
Goblet cell carcinoid of the large intestine is a rare neoplasm, usually located in ascending colon and rectum. A 60-year-old male patient underwent surgery after the diagnosis of acute abdomen. Exploratory laparotomy revealed perforation with a diameter of 1 cm at the site of the previously performed gastroenterostomy and dilatation of the right colic flexure, secondary to a solid obstructive mass located in the mid-portion of transverse colon. Histopathological investigation of the biopsies, taken from the gastroenterostomy site and the tumor, revealed mixed carcinoid-adenocarcinoma with carcinoid component, predominantly composed of goblet cells. Three cycles of FOLFOX-4 protocol was administered. Following respiratory distress secondary to pulmonary metastasis, the patients condition deteriorated and subsequently died in the fourth postoperative month. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm.