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Öğe The effects of synthetic organoselenium compounds on nitric oxide in DMBA - Induced rat liver(Triveni Enterprises, 2009) Talas Z.S.; Bayraktar N.; Ozdemir I.; Gok Y.; Yilmaz I.DMBA (7,12-dimethylbenz[a]anthracene) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. Since selenium is known as a non-enzymic antioxidant, health problems induced by many environmental pollutants, have stimulated the evaluation of relative antioxidant potential of selenium and synthetic organoselenium compounds. Therefore, we aimed to evaluate chemopreventive potential of synthetic organoselenium compounds by monitoring level of liver nitric oxide. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (Se I) and (Se II) in the determined doses. DMBA-induced in rats, the effects of organoselenium compounds on nitric oxide levels in rat liver was studied. In this study, it has been observed a statistically significant increase in (Nitric Oxide) levels for the liver of rat exposed to DMBA (p<0.05). However with administration of Se I and Se II there was a statistically significant decrease in NO levels (p<0.05). The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rat livers was rationalized. Protection against nitric oxide measured in Se I and Se II treated groups were provided by synthesized organoselenium compounds. Se I and Se II both provided chemoprevention against DMBA-induced oxidative stress in rat liver. © Triveni Enterprises.Öğe Evaluation of serum levels of immunoglobulins (IgA, IgE, IgG, IgM) complements (C3, C4) and C-reactive protein in bladder cancer: A controlled prospective clinical trial(2005) Kiliç S.; Bayraktar M.; Bayraktar N.; Ergin H.; Beytur A.; E?ri M.Introduction: During the management of a patient with bladder cancer, the aim of a clinician is to diagnose the tumor with a most sensitive and least invasive method. Cystoscopy and urine cytology are standard practice in following these patients; however, cystoscopy is invasive, and urine cytology has low sensitivity. Therefore, this study aims to evaluate the diagnostic and prognostic value of the humoral immunity in the bladder cancer patients by means of measuring serum levels of immunoglobulins, complements and C-reactive protein pre and postoperatively compared with controls. Materials and methods: Blood and urine samples were taken from both tumor and control patients preoperatively and from only tumor patients at postoperative 1 and 3 months. Urine samples were examined immediately for microscopic examination and culturing. Serum samples were stored at -80°C in a deep freeze till processing and assessed blindly by same person at the end of the study. Patients who preoperatively received intravesical BCG instillation therapy, radiotherapy or chemotherapy for their bladder carcinoma diseases were not included in tumor group. Patients who underwent a transurethral procedure for a non-neoplastic genitourinary disease and did not have any documented cancer, served as controls. Results: Mean ages of tumor (20 pts; 1 female, 19 males) and control (41 pts; 3 females, 38 males) patients were 64.2±9.9 and 63.7±8.9, respectively (p=0.846). All tumor patients completed 3 months of follow-up. There was no statistical difference in urinary infection incidences between tumor and control groups. Serum IgA, IgE, IgG, C3 and CRP levels were statistically significantly higher in tumor group than in control group, while lower C4 and indifferent IgM levels were present in tumor group compared to control. However following tumor resection, all of them decreased very significantly. All serum levels, except C4, of 6 patients with visible tumor in their bladders at postoperative 3rd month were similar to those of tumor-negative patients. Although preoperative high levels of IgA, IgE, IgG, C3 and CRP appeared as sensitive, specific and predictive in primary bladder tumor diagnosis, post-treatment levels of any of those above were not found as useful in follow-up, suggesting that these were not diagnostic and prognostic parameters for bladder tumor. No correlation was established between infection and serum levels in both groups since there were not statistically significant differences in serum immunoglobulins, complements and CRP levels between the patients with and without urinary infection in each group. Pathologic stage and grade of the tumor did not correlate with immunoglobulin and C4 levels. However, there was a significant positive correlation between stage and C3 or CRP. There were no differences between the 3rd month serum levels of patients who took no therapy (6 pts) or chemotherapy (5 pts) or intravesical BCG (9 pts) after resections, except C4 which was higher in patients who took chemotherapy than in those who took BCG. Conclusion: Although serum immunoglobulins, complements and CRP appear to be nondiagnostic for primary bladder carcinoma, wider studies with longer follow-up and higher patient population are necessary for more definitive conclusions.Öğe excretion rate and composition of skin surface lipids on the foreheads of adult males with type iv hyperlipoproteinemia(2007) Güldür T.; Bayraktar N.; Koçer M.; Kaynar O.; Beker G.; Özcan H.Objectives: Most of the lipids of the skin surface come from sebaceous glands secretions, called sebum. Some of the sebum lipids are synthesized by sebaceous cells while some are reportedly derived from the plasma. Role of blood lipoproteins in sebum secretion rate and composition is unclear. To this end, excretion rate and composition of skin surface lipids of normo- and type IV hyperlipoproteinemic subjects were compared. Design and Methods: Quantitative analysis of skin surface lipids was performed by three successive sampling on left, middle, and right zones of the forehead with a sebumeter. Skin surface lipid samples for the compositional analysis were collected from the forehead, extracted into n-hexane, and analyzed by high performance thin layer chromatography (HPTLC). HPTLC plates were scanned with a densitometer for the quantification of the lipids. Results: Skin surface lipids from type IV hyperlipoproteinemic subjects contained higher proportion of wax. © 2007, by Walter de Gruyter GmbH & Co. All rights reserved.Öğe Serum electrolytes and nitric oxide levels in acute hypotension following intravenous heparin(2006) Toprak H.I.; Begec Z.; But A.; Sizanli E.; Bayraktar N.; Ersoy M.O.Heparin is frequently used as an anticoagulant agent for patients undergoing surgery with cardiopulmonary bypass. In literature, severe hypotension as a side effect of high dose bolus heparin has been already reported. However, the exact mechanism of hypotension has not yet fully been understood. The aim of the study was to investigate the relationship between hemodynamic instability induced by heparin and levels of serum electrolytes and nitric oxide. Forty patients undergoing elective coronary artery bypass grafting were included into the study. Patients with sudden decrease in mean arterial pressure (MAP) higher than 25 % of the baseline after heparin administration were included into group H (n=20). Besides, consecutive twenty hemodinamically stabile patients (with none or a MAP decrease lower than 25 % of baseline) constituted group N (n=20). Anesthetic techniques were standardized. Arterial blood gases were analyzed for pH, PaO2, PaCO2, potassium, sodium, calcium, magnesium, hematocrit before and 5 minutes after heparin administration. Synchronous serum nitric oxide levels analysis were also performed. The nitric oxide levels were measured as reflected by the formation of its stable end-metabolites, nitrite and nitrate. Serum electrolyte and nitric oxide levels were not statistically different neither between before and after heparin administration nor between hypotension group and normotension group. Hypotension observed after heparin administration was not related with the concentration of serum electrolytes and nitric oxide.
