Yazar "Özbek, E" seçeneğine göre listele
Listeleniyor 1 - 5 / 5
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Adrenomedullin and nitrite levels in children with primary nocturnal enuresis(Springer, 2002) Balat, AE; Çekmen, M; Yürekli, M; Gül, AK; Özbek, E; Korkut, M; Tarakçioglu, MPrimary nocturnal enuresis (PNE) is the most common type of nocturnal enuresis in children, but its etiology remains unclear. Recent studies indicated the differences in urinary electrolytes in enuretic children, and stressed the existence of a renal tubular maturation defect. In this study, 30 children (aged 6-12 years) with PNE were investigated in comparison with 18 healthy controls. We evaluated plasma antidiuretic hormone, electrolytes, 24-h urine volume, osmolarity, and urinary electrolytes. Unlike other studies, we firstly assessed the plasma and urinary adrenomedullin (AM) and total nitrite levels, a stable product of nitric oxide (NO), and investigated their relationship with urinary electrolytes. The plasma AM and total nitrite levels were significantly lower than controls. Urine volume (24-h) and potassium excretion were higher than in controls. However, 24-h urinary osmolarity and excretion of AM were significantly lower than in controls. Our results indicate that there may be a problem in renal regulation of potassium in children with PNE. Although decreased levels of AM and total nitrite may be a compensatory response to abnormal potassium and water excretion, further investigations are required to exclude whether the renal synthesis of AM and NO are also deficient in these children.Öğe Malondialdehyde level and total superoxide dismutase activity in seminal fluid from patients with varicocele(Springer-Verlag, 2001) Akyol, Ö; Özbek, E; Uz, E; Koçak, I[Abstract Not Available]Öğe Melatonin administration prevents the nephrotoxicity induced by gentamicin(Wiley, 2000) Özbek, E; Turkoz, Y; Sahna, E; Ozugurlu, F; Mizrak, B; Ozbek, MObjective To investigate the effect of melatonin on the antioxidant enzyme activity and renal tubular necrosis induced by gentamicin. Materials and methods Twenty-four adult male Sprague-Dawley rats were divided into three equal groups. In group 1, the rats were injected with vehicle (controls), in group 2 they were injected with gentamicin for 5 days and in group 3 injected with gentamicin plus melatonin for 5 days. At 24 h after the last injection, rats were killed and the renal cortex separated from the medulla. Most of the cortex was homogenized but a small sample was fixed in formaldehyde solution for histological examination by light microscopy. Blood samples were also taken to assess the serum levels of urea, creatinine, Na+, K+ and gamma-glutamyl transpeptidase (gamma-GT); before death, urine samples were analysed for protein content. Crude extracts of the cortex were used to deter-mine lipoperoxides, reduced glutathione (GSH-Px), catalase and superoxide dismutase (SOD). The results were compared using the Mann-Whitney U-test. Results Compared with the controls rats, gentamicin caused hyperproteinuria, an increase in the level gamma-GT In serum, a marked increase in lipoperoxides and a signifcant decrease of GSH-Px, catalase and SOD activity in the kidney. In the rats in group 3 there was a marked restoration in lipid peroxidation, GSH-Px, catalase, SOD activity and proteinuria, and in gamma-GT in serum. In rats in group 2 there was widespread tubular necrosis (grade 2-4) but in rats in group 3 there was a merited reduction in the extent of tubular damage. There was no significant difference in serum levels of Na+, K+, blood urea nitrogen and creatinine. Conclusion These results indicate that melatonin prevents the tubular necrosis induced by gentamicin in rats, presumably because it is a potent antioxidant and restores antioxidant enzyme activity in the rat kidney.Öğe Urinary adrenomedullin levels are increased and correlated with plasma concentrations in patients with Behcet's syndrome(Wiley-Blackwell, 2002) Evereklioglu, C; Özbek, E; Er, H; Çekmen, M; Yürekli, MBackground: The objective was to measure urinary adrenomedullin (AM) levels in patients with active or inactive Behcet's syndrome and compare them to levels in healthy control subjects. Methods: Forty-five consecutive patients with Behcet's syndrome (20 men and 25 women with a mean age of 37.7 +/- 10.8 years) and 20 age- and sex-matched healthy hospital staff volunteers as control subjects (nine men and 11 women with a mean age of 36.2 +/- 10.4 years) were studied. Urinary and plasma AM concentrations were measured by high-performance liquid chromatography. We also investigated whether disease activity correlates with urinary and plasma AM levels. The Mann-Whitney U -test was used in statistical analysis and the values were expressed as mean +/- SD. Results: Urinary excretion of AM (pmol per mg urinary creatinine) in patients with Behcet's syndrome (81.3 +/- 35.1) was significantly higher (P < 0.001) than in control subjects (31.2 +/- 16.1). Plasma AM levels (pmol/L) in patients with Behcet's syndrome and controls were 69.1 +/- 19.2 and 20.7 +/- 11.8, respectively; the difference was significant (P < 0.001). Although active Behcet's syndrome patients (n = 22) had higher urinary AM levels (92.1 +/- 41.1) compared to inactive (n = 23; 70.8 +/- 32.2), the difference was not significant (P > 0.05). Plasma AM levels in active Behcet's syndrome patients (77.5 +/- 21.2) were also higher than in inactive (61.6 +/- 17.3), but the difference was not significant (P > 0.05). Conclusion: Urinary AM levels were higher in Behcet's patients than in control subjects. Urinary AM levels were correlated with plasma AM levels. The results suggest that the higher AM levels found in the urine may be produced by the kidney as a result of the stimulation of inflammation during the course of Behcet's syndrome, or may come from plasma, as plasma AM levels were increased. However, the exact sites of AM synthesis by the kidney (e.g. glomeruli, blood vessels and/or tubular cells) could not be determined in this study. Further studies in this respect are necessary.Öğe Urinary nitric oxide levels are increased and correlated with plasma concentrations in patients with Behcet's disease(Wiley, 2003) Evereklioglu, C; Özbek, E; Çekmen, M; Mehmet, N; Duygulu, F; Ozkiris, A; Çalip, MNitric oxide ( NO) is a free radical and serves many functions within the kidney. Excess NO causes glomerular injury. Behcet's disease (BD) is a systemic immunoinflammatory vasculitis, affecting every organ in the body including the kidneys ( subclinic glomerulonephritis). We investigated the role of urinary total nitrite levels (end product of NO) in BD and evaluated whether urinary concentrations were correlated with its plasma levels or disease activity. Thirty-six consecutive Behcet's patients (19 men, 17 women; 35.9 years), and 20 age- and sex-matched healthy control volunteers (12 men, eight women; 33.2 years) were divided into an active (n = 16) and inactive ( n = 20) period. Urinary and serum NO levels (mumol/mg urinary creatinine) were higher in BD patients (4.1 +/- 0.3) than control subjects (1.7 +/- 0.2; P < 0.001). Serum NO levels in Behcet's patients and control subjects were 51.3 +/- 9.8 and 21.7 +/- 7.3 mu mol/ L, respectively (P < 0.001). Active patients had higher urinary NO excretion (4.9 +/- 0.3) than inactive patients (3.3 +/- 0.3; P < 0.01). Urinary NO levels were correlated with its serum levels (r(2) = 0.69, P < 0.001). Higher urinary NO levels found in BD may be produced by the kidney as a result of an inflammatory stimulation. As excess NO is toxic to the tissues, increased NO levels may play a role in mediating subclinic glomerular injury of such patients. However, we could not determine the exact site(s) of NO synthesis by the kidney, such as the glomeruli, blood vessels and/or the tubular cells. Whatever the source, urinary NO levels may be used as a new activity marker in the diagnosis and follow up of BD by serial measurements.
