Yasemin Erten

Gazi University, Ankara, Ankara, Turkey

Are you Yasemin Erten?

Claim your profile

Publications (27)33.76 Total impact

  • Article: Novel Inflammatory Marker in Dialysis Patients: YKL-40.
    [show abstract] [hide abstract]
    ABSTRACT: YKL-40 has been introduced as a marker of inflammation in different clinical situations. The association between YKL-40 and inflammation in chronic renal failure patients has not been researched currently. The objectives of this study were to establish serum YKL-40 concentrations in dialysis patients with chronic renal failure compared to healthy subjects and to explore its relationships with a proinflammatory cytokine, interleukine-6 (IL-6) and an acute phase mediator, high sensitivity C-reactive protein (hs-CRP). The study population included hemodialysis patients (N = 43; mean age of 40.9 ± 14.5), peritoneal dialysis patients (N = 38; mean age of 45.8 ± 13.7) and healthy subjects (N = 37; mean age of 45.5 ± 10.6). Serum concentrations of YKL-40, IL-6, hs-CRP and routine laboratory measures were evaluated. Compared to the healthy subjects, hemodialysis and peritoneal dialysis patients had higher concentrations of YKL-40, IL-6, hs-CRP, as well as lower concentrations of hemoglobin, serum albumin and high density lipoprotein-cholesterol (P < 0.001). YKL-40 concentrations were positively correlated with serum creatinine (P < 0.001, r = 0.495), IL-6 (P < 0.001, r = 0.306), hs-CRP (P = 0.001, r = 0.306) levels and inversely correlated with hemoglobin (P = 0.002, r = -0.285), serum albumin (P < 0.001, r = -0.355) and high density lipoprotein-cholesterol (P = 0.001, r = -0.306). In multivariate regression analysis YKL-40 was associated with creatinine, serum albumin and hs-CRP concentrations after adjustments with covariates. Dialysis patients with chronic renal failure have elevated serum YKL-40 concentrations. Associations with standard inflammatory parameters suggest that YKL-40 might be a novel inflammatory marker in this population.
    Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 04/2013; 17(2):193-201. · 1.39 Impact Factor
  • Article: A novel therapeutic approach to resistant hypertension: renal sympathetic denervation.
    Anadolu kardiyoloji dergisi: AKD = the Anatolian journal of cardiology 12/2012; · 0.44 Impact Factor
  • Article: The effects of iron on FGF23-mediated Ca-P metabolism in CKD patients.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Fibroblast growth factor 23 (FGF23) is an important counterregulatory hormone for phosphate homeostasis. Since it has been reported that iron administration induces hypophosphatemic osteomalacia by triggering FGF23 synthesis, we hypothesized that iron administration might lead to a further increase in FGF23, resulting in alterations to Ca-P metabolism in a stage 5 CKD population. METHODS: This cross-sectional study was performed in a single center, and involved 73 hemodialysis patients (47.7 ± 15.74 years old, 68.5 % men), 29 peritoneal dialysis patients (44.55 ± 15.05 years old, 62.1 % men), and 55 healthy (43.57 ± 14.36 years old, 55.6 % men) subjects. The dialysis group was subcategorized according to iron therapy administration into users and nonusers. RESULTS: The median iFGF23 level was significantly higher in the dialysis population than in the healthy controls [88.050 (25.2-1038.3) pg/ml versus 46.95 (2.4-356) pg/ml (p < 0.001)]. In the dialysis population, a significantly lower median iFGF23 level was observed in iron therapy users than in nonusers [87.6 (25.2-1038.3) versus 119 (51.6-1031); respectively, p = 0.045]. A significant negative association between iron administration and iFGF23 level was revealed by both univariate (r = -0.237, p = 0.016) and multivariate (β = -0.221, p = 0.032) analysis. No association was found between iFGF23 and serum ferritin and iron levels. Also, there was no association between iron therapy and serum phosphate level. CONCLUSION: In contrast to what is seen for the general population, this study showed that there was a negative relationship between iron administration and serum iFGF23 level in a dialysis population. We can therefore conclude that if high levels of FGF23 are harmful, iron therapy may have a beneficial effect on bone metabolism by reducing FGF23 levels in a dialysis population.
    Clinical and Experimental Nephrology 11/2012; · 1.37 Impact Factor
  • Article: Neutrophil to Lymphocyte Ratio in Evaluation of Inflammation in Patients with Chronic Kidney Disease.
    [show abstract] [hide abstract]
    ABSTRACT: Aim: The current data have proven the pivotal role of inflammation in the development of atherosclerosis and cardiovascular diseases in patients with chronic kidney disease (CKD). Neutrophil to lymphocyte (N/L) ratio has increasingly been reported as a measure of systemic inflammation. This study assessed N/L ratio and investigated its associations with standard inflammatory biomarkers in different stages of CKD patients. Material and methods: This cross-sectional study included 30 predialysis, 40 hemodialysis, 35 peritoneal dialysis patients, and 30 healthy subjects. N/L ratio and important clinical and laboratory parameters were registered. Multivariate regression analyses were carried out to investigate the relations of N/L ratio. Results: N/L ratio was significantly higher in each patient group compared to the healthy subjects (for all, p < 0.001). It was positively correlated with interleukin-6 (IL-6) (r = 0.393, p < 0.001) and high-sensitivity C-reactive protein (hs-CRP) (r = 0.264, p = 0.002) levels and negatively correlated with hemoglobin (r = -0.271, p = 0.001), serum albumin (r = -0.400, p < 0.001), and high-density lipoprotein (HDL) cholesterol levels (r = -0.302, p < 0.001). In CKD patients with hypertension (HT), higher N/L ratio was detected when compared to those without HT (p = 0.006). Having CKD, the presence of HT, serum albumin, HDL-cholesterol, IL-6, and hs-CRP levels were found to be independent predictors of the ratio after adjusting for significant covariates (p < 0.001). Conclusion: An easy and inexpensive laboratory measure of N/L ratio might provide significant information regarding inflammation in CKD including predialysis and dialysis patients.
    Renal Failure 11/2012; · 0.82 Impact Factor
  • Article: Protective effect of beta-glucan on contrast induced-nephropathy and a comparison of beta-glucan with nebivolol and N-acetylcysteine in rats.
    [show abstract] [hide abstract]
    ABSTRACT: It has been shown that beta-glucan (BG), which has antioxidant and immunomodulatory effects, attenuats renal ischemia-reperfusion injury. We aimed to investigate whether BG might have a preventive role against the development of contrast-induced nephropathy and to compare its effect with nebivolol (Nb) and N-acetylcysteine (NAC). Thirty-six Wistar albino female rats were randomly divided into six groups (n = 6 each): control, contrast media (CM), BG, BG + CM, Nb + CM, and NAC + CM. With the exception of control and CM groups, the others were given drugs orally once a day for 5 days. Kidney function parameters, inflammatory parameters, and serum and renal tissue oxidative stress markers were measured. Increases of serum creatinine and blood urea nitrogen levels were significantly higher (p < 0.05) in the CM group only. Absolute changes of serum creatinine levels in BG, BG + CM and Nb + CM groups were significantly lower than those in the CM group (p < 0.05). Serum levels of advanced oxidation protein products and malondialdehyde were significantly less (p < 0.05) in the BG group compared to the CM group. Histopathological lesions in the CM group were more advanced (p < 0.05). No significant differences between the BG + CM, Nb + CM and NAC + CM groups were found with regard to histopathological findings. This study suggests that BG protects or ameliorates against contrast-induced nephropathy. Its beneficial effects may be similar to or greater than those of Nb or NAC.
    Clinical and Experimental Nephrology 04/2011; 15(5):658-65. · 1.37 Impact Factor
  • Article: A case of an accelerated uremic neuropathy.
    [show abstract] [hide abstract]
    ABSTRACT: We present a 62-year-old man, with a prior history of diabetes mellitus, atherosclerotic heart disease, and chronic renal failure requiring peritoneal dialysis, who developed accelerated uremic sensorimotor polyneuropathy. Our patient significantly improved after effective hemodialysis. Although renal transplantation is a curable therapy for uremic neuropathy, effective dialysis is still an important treatment for the group of patients who cannot undergo renal transplantation.
    Renal Failure 01/2011; 33(3):371-2. · 0.82 Impact Factor
  • Article: Operational tolerance after immunosuppressive withdrawal in a case with renal transplantation.
    Southern medical journal 01/2011; 104(1):74. · 0.92 Impact Factor
  • Article: Association of the angiotensinogen M235T and APO E gene polymorphisms in Turkish type 2 diabetic patients with and without nephropathy.
    [show abstract] [hide abstract]
    ABSTRACT: Diabetic nephropathy (DN) is a leading cause of diabetes-related morbidity and mortality. The aim of this study was to evaluate the relationship of AGT M235T and apoprotein E (APO E) gene polymorphism with DN in Turkish patients of Type 2 diabetes, and to compare genotype and allele distributions among DN patients, non-DN patients, and healthy controls. AGT M235T and APO E genotype and allele analysis were performed in 111 DN patients, 108 non-DN patients, 106 healthy control subjects for APO E genotype, and 100 for AGT M235T genotype polymorphism. APO E and AGT M235T genotype were determined by RFLP-PCR. Results: The frequencies of APO E ε2/3, ε 3/3, ε 3/4 genotypes were 22.7%, 60%, 60%, respectively, among DN patients and 6.6%, 80%, 10.4%, respectively (p < 0.001), in the non-DN patients. The frequencies of AGT M235T MM, MT, TT genotypes among the same groups were 17%, 46%, 37% and 21%, 63%, 16%, respectively (p < 0.02). Having the ε2/3 genotype and TT genotype increased the risk for DN nephropathy [4.8-fold (95% CI: 1.94-11.67), 2.9-fold (95% CI: 1.27-6.69), respectively]. Our study has shown that AGT M235T TT genotype and APO E ε 2/3 genotype may be linked to a risk for DN among Turkish population.
    Renal Failure 01/2011; 33(5):469-74. · 0.82 Impact Factor
  • Article: Predictive markers of asymptomatic atherosclerosis in end-stage renal disease patients.
    [show abstract] [hide abstract]
    ABSTRACT: Uremia is associated with accelerated atherosclerosis and increased cardiovascular mortality in patients with end-stage renal disease (ESRD). Cardiac injury markers, such as myoglobin, creatine kinase-MB (CK-MB), or troponins, frequently used to recognize acute coronary events, may be falsely elevated in this patient group. In this study, our aim was to (i) test serum levels of myoglobin, CK-MB, and troponin I (cTnI) in ESRD patients without coronary artery disease (CAD) and compare the results with healthy controls and (ii) to investigate the association between these markers and carotid artery intima-media thickness (CA-IMT), high-sensitive C-reactive protein (hs-CRP), and serum uric acid (SUA) levels in ESRD patients. Fifty-two ESRD patients (25 hemodialysis and 27 peritoneal dialysis) and 17 healthy controls were included in the study. Serum levels of myoglobin, CK-MB, and cTnI were measured and ultrasonographic CA-IMT was determined in all participants. SUA and hs-CRP levels were only measured in the ESRD group. Serum myoglobin, CK-MB levels, and the mean CA-IMT were significantly higher in ESRD group (p < 0.01), whereas cTnI levels were not different compared to healthy controls (p = 0.70). There was also a positive correlation between CA-IMT and cTnI levels (p = 0.003, r = 0.35) and CA-IMT and hs-CRP (p = 0.03, r = 0.30) or SUA levels (p = 0.003, r = 0.43). cTnI may serve as a more sensitive marker in detecting cardiovascular events in patients with renal failure. Besides the traditional risk factors of atherosclerosis, cTnI, hs-CRP, and SUA may have a predictive role in recognizing premature atherosclerosis in ESRD patients.
    Renal Failure 05/2010; 32(4):448-54. · 0.82 Impact Factor
  • Article: Effects of everolimus on cytokines, oxidative stress, and renal histology in ischemia-reperfusion injury of the kidney.
    [show abstract] [hide abstract]
    ABSTRACT: To evaluate the effects of everolimus on renal ischemia-reperfusion injury (IRI). Wistar albino rats were divided into control, ischemia-reperfusion (IR), and ischemia-reperfusion/everolimus (IR/eve) groups. Everolimus was administered for seven consecutive days to the IR/eve group prior to injury. IR and IR/eve groups underwent forty-five minutes ischemia followed by the application of reperfusion at 2 and 24 hours. Blood samples and kidneys were taken from all animals. . Serum blood urea nitrogen and creatinine levels increased at two hours of reperfusion in the IR and IR/eve groups, and decreased at 24 hours of reperfusion in the IR group. In the IR/eve group, we detected significantly high interleukin-6 levels and low tumor necrosis factor-alpha and malondialdehyde levels at 24 hours. Myeloperoxidase levels increased at two hours of reperfusion in the IR/eve group, but decreased significantly at 24 hours. Everolimus did not improve renal tubular and interstitial injuries in renal IRI. It has been demonstrated that pretreatment with everolimus has beneficial effects on cytokines and oxidative stress in renal IRI. However, these effects are insufficient for the correction of histopathological changes and restoration of normal kidney function.
    Renal Failure 01/2009; 31(8):698-703. · 0.82 Impact Factor
  • Article: Prevalence of cholelithiasis in a Turkish population of end stage renal failure patients and related risk factors: experience of a center from Turkey.
    The Turkish journal of gastroenterology: the official journal of Turkish Society of Gastroenterology 07/2008; 19(2):139-40. · 0.47 Impact Factor
  • Article: The relationship between vascular endothelial growth factor (VEGF) and microalbuminuria in patients with essential hypertension.
    [show abstract] [hide abstract]
    ABSTRACT: The existence of microalbuminuria (MAU) in patients with essential hypertension is a strong indicator of microvascular damage. Although endothelial dysfunction and increased vascular permeability both have a role in the development of MAU, its ethiopathogenesis in hypertensive patients is not yet clearly understood. Vascular endothelial growth factor (VEGF) is the most important regulator of pathological or physiological angiogenesis and it additionally leads to increased vascular permeability. This study aims to assess the relationship of serum VEGF levels to MAU in non-complicated, newly-diagnosed essential hypertensive patients (EHs). This study included 30 newly-diagnosed EHs with MAU, 46 newly-diagnosed EHs without MAU and 46 healthy controls. None of the EHs had diabetes, renal impairment or atherosclerotic diseases. Serum VEGF levels were measured using the ELISA method. Serum levels of VEGF were significantly higher in EHs with MAU when compared with patients without MAU (225.15+/-109.34 pg/mL versus 166.78+/-114.35 pg/mL, p: 0.04) or controls (225.15+/-109.34 pg/mL versus 144.91+/-96.60 pg/mL, p: 0.007). On the other hand, no significant difference was observed between the non-MAU and control groups. In the univariate analysis, serum levels of VEGF, were positively correlated with systolic blood pressure (R: 0.253 p: 0.001), diastolic blood pressure (R: 0.162 p: 0.04), mean arterial pressure (R: 0.239 p: 0.002), creatinine clearance (R: 0.172 p: 0.04) and MAU (R: 0.338 p: 0.002). In the multiple linear regression analysis, VEGF levels were independently related to MAU (beta: 0.248, p: 0.02). VEGF levels are higher in EHs in the presence of MAU. These high values may be important in the early diagnosis of vascular damage in EHs. Additionally, VEGF may increase glomerular permeability and lead to MAU in EHs.
    Internal Medicine 02/2008; 47(17):1511-6. · 0.94 Impact Factor
  • Article: The relationship among asymmetric dimethylarginine (ADMA) levels, residual renal function, and left ventricular hypertrophy in continuous ambulatory peritoneal dialysis patients.
    [show abstract] [hide abstract]
    ABSTRACT: Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial-based nitric oxide synthase. Its level is increased by end stage renal disease. However, most studies showing an increase in ADMA in dialysis patients have focused on hemodialysis. Results with peritoneal dialysis patients have been more inconclusive. Recent studies suggest that ADMA may be a new cardiovascular risk factor. The aim of the present study was to evaluate the relationship between ADMA levels, residual renal function, and left ventricular hypertrophy in peritoneal dialysis patients. Serum ADMA measurements and echocardiographic evaluations were performed in 54 peritoneal dialysis patients and 26 healthy volunteers. Residual renal function was measured in peritoneal dialysis patients by urea clearance from a urine collection. Thirty-two of the 54 peritoneal dialysis patients had residual renal function. ADMA levels of the peritoneal dialysis group were found to be significantly higher than those of healthy individuals (p = 0.03). Within the peritoneal dialysis group, ADMA levels of patients with residual renal function were significantly lower than those without residual renal function (p = 0.01), though they were still higher than the ADMA levels of the control group (p = 0.04). Serum levels of ADMA were positively correlated with left ventricular mass index (r = 0.29, p = 0.01) and negatively correlated with early mitral inflow velocity (Em) (r = -0.28, p = 0.01), Em/Late mitral inflow velocity (Am) (r = -0,32, p = 0.00), and isovolumetric relaxation time (r = -0.30, p = 0.01). In conclusion, increased ADMA levels seem to be associated with left ventricular hypertrophy in peritoneal dialysis patients, and residual renal function may lead to a reduction of serum ADMA levels.
    Renal Failure 02/2008; 30(4):401-6. · 0.82 Impact Factor
  • Article: TGF-beta1 gene polymorphisms and peritoneal equilibration test results in CAPD patients.
    [show abstract] [hide abstract]
    ABSTRACT: Transforming growth factor-beta1 (TGF-beta1) stimulates the expression of collagen mRNA in cultured human peritoneal mesangial cells, which may predispose them to developing peritoneal fibrosis. Polymorphisms in the signal sequence genetically may be responsible for increased TGF-beta1 production (i.e., a substitution at amino acid position 10 and 25, +869 Leu(10)-Pro and +915 Arg(25)-Pro, respectively). The aim of this study was to find out whether there is any relation between peritoneal equilibration test (PET) results and TGF-beta1 gene polymorphism. Thirty-two CAPD patients and 72 healthy subjects were included into the study. Each CAPD patient had undergone two PET with a two-year interval. The patients were classified according to the results of a baseline PET as high (high-high average) and low (low-low average) transporters. In high transporters group (n = 20), the genotype frequencies were found as 45% Leu/Leu, 55% Leu/Pro for codon 10; and 85% Arg/Arg, 15% Arg/Pro for codon 25. In low transporters group (n = 12), the genotype frequencies were detected as 66.7% Leu/Leu and 33.3% Leu/Pro for codon 10; and 83.3% Arg/Arg, 16.7% Arg/Pro for codon 25. The distribution of the TGF-beta1 genotypes in our control population was compatible with a Hardy-Weinberg equilibrium. We found no relation between TGF-beta1 genotypes and peritoneal transport group (chi(2) test, p > 0.5). There was no relation between TGF-beta1 genotype and longitudinal change in peritoneal transport. This study is the first study analyzing the possible link between TGF-betal gene polymorphisms and the characteristics of peritoneal transport and longitudinal change of peritoneal transport characteristics in CAPD patients. Further work is needed to clarify the functional importance of these two polymorphisms in TGF-beta1 production and in the development of peritoneal fibrosis.
    Renal Failure 01/2008; 30(1):15-9. · 0.82 Impact Factor
  • Article: The relationship of visfatin levels to inflammatory cytokines and left ventricular hypertrophy in hemodialysis and continuous ambulatory peritoneal dialysis patients.
    [show abstract] [hide abstract]
    ABSTRACT: Visfatin was recently defined as an adipocytokine; however, the pathophysiological role of visfatin is not completely understood. A few studies suggest that visfatin may be a new proinflammatory adipocytokine. The aim of the present study was to compare serum visfatin levels between hemodialysis and continuous ambulatory peritoneal dialysis (CAPD) patients and evaluate the relationship between visfatin levels to IL-6, TNF-alpha, and left ventricular hypertrophy. Serum visfatin, IL-6, and TNF-alpha levels were measured by using the ELISA method, and echocardiographic evaluations were performed in 31 hemodialysis patients, 30 CAPD patients, and 21 healthy volunteers. Serum visfatin levels were higher in the CAPD group (265.27 +/- 387.86 ng/mL) than hemodialysis (97.68 +/- 244.96 ng/mL,) and control (41.33 +/- 48.87 ng/mL) groups (p = 0.04, p = 0.01, respectively). No significant difference was observed between the hemodialysis and control groups. In univariate analysis, visfatin levels were positively correlated with IL-6 (r = 0.24, p = 0.03), TNF-alpha (r = 0.34, p = 0.002), and BMI (r = 0.26, p = 0.03) and negatively correlated with some left ventricular diastolic parameters [Em and Em/Am (r = -0.305, p = 0.01), (r = -0.251, p = 0.03), respectively]. No relationship was found between visfatin and left ventricular mass index. In the linear regression analysis, visfatin levels independently related with TNF-( (beta = 0.369, p = 0.001) and IL-6 (beta = 0.284, p = 0.015). This study has found significantly higher levels of serum visfatin in CAPD patients when compared to healthy individuals. Increased visfatin levels seem to associate with proinflammatory cytokines such as IL-6 or TNF-alpha. As for the effects of on left ventricular structure and functions, visfatin might have negative effects on left ventricular diastolic function parameters but have no effects on left ventricular mass index.
    Renal Failure 01/2008; 30(6):617-23. · 0.82 Impact Factor
  • Article: A case with full clinical manifestations of Dorfman-Chanarin syndrome
    [show abstract] [hide abstract]
    ABSTRACT: Dorfman-Chanarin syndrome (DCS), is a rare, autosomal recessive disorder associated with lipid metabolism. It is characterized by ichthyosiform nonbullous erythroderma, lipid vacuoles in peripheral leukocytes and variable involvement of organs. We report a Turkish man with the complete syndrome, who described family history of ichthyosis. To best of our knowledge this is the sixth case from Turkish origin to date. In addition to congenital ichthyosis he had also strabismus, horizantal nystagmus, bilateral neurosensory hearing loss, hepatomegaly and splenomegaly. Liver biopsy revealed hidrophic degeneration in hepatocytes, steatosis, enlargement and inflammation in portal areas and portal central fibrosis, consistent with cirrhosis. Write stained peripheral blood smear examination revealed lipid vacuoles in all of the neutrophils consistent with Jordan’s anomaly. We think that, it is essential to evaluate the peripheral blood smear of the patients with ichthyosis and also patients with DCS should be informed and warned about the results of consanquinous marriage.
    Central European Journal of Medicine 02/2007; 2(1):116-121. · 0.31 Impact Factor
  • Article: B-flow sonographic evaluation of hemodialysis fistulas: a comparison with low- and high-pulse repetition frequency color and power Doppler sonography.
    [show abstract] [hide abstract]
    ABSTRACT: The purpose of this study was to determine the effectiveness of B-flow sonography in the evaluation of hemodialysis fistulas and to compare this new technique with color and power Doppler sonography. In this study, 32 randomly selected patients (mean age, 46 years; age range, 18-87 years) with normally functioning hemodialysis fistulas were evaluated with low- and high-pulse repetition frequency (PRF) color and power Doppler sonography (PRF values of 3 and 10 kHz) and B-flow sonography. All images were reviewed and graded independently by 2 observers for luminal filling with flow signals, visibility of the intimal layer, and overall image quality. The study was approved by the Institutional Review Board, and informed consent was obtained from all patients. Statistical analysis with Friedman and Wilcoxon signed rank tests revealed that B-flow sonography was superior to other techniques for luminal filling and visibility of the intimal layer (P = .000). For overall image quality, B-flow sonography was also the best method according to the Friedman test (P = .000). However, the Wilcoxon test showed no significant difference between B-flow and high-PRF (10-kHz) color and power Doppler sonography (P = .131). The kappa scores reflected moderate to good interobserver agreement (kappa = 0.285-0.784). B-flow sonography is a relatively new and superior imaging technique that provides direct visualization of the blood echoes and the morphologic characteristics of the surrounding vessel wall simultaneously. During the evaluation of hemodialysis shunts, the major advantage of this technique is its ability to avoid artifacts such as aliasing and overwriting.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 12/2005; 24(11):1503-8; quiz 1509-10. · 1.25 Impact Factor
  • Article: Effects of amifostine on glycerol-pretreated rabbit kidneys.
    [show abstract] [hide abstract]
    ABSTRACT: Glycerol-induced acute renal failure is an experimental model for myoglobinuric nephropathy. Amifostine is a cytoprotective agent which scavenges the free radicals. Since there is enhanced production of reactive oxygen metabolites in glycerol-induced acute renal failure, we wanted to examine whether amifostine has a protective role against vascular reactivity and histological changes in kidneys isolated from glycerol-pretreated rabbits. Perfusion pressure was recorded from kidneys obtained from rabbits injected with glycerol 3 hr before the experiments and from glycerol-pretreated and non-pretreated rabbits injected with amifostine 30 min. before the experiments. Acetylcholine-induced (10(-8)-10(-5) M) vasodilatation was tested following the construction of submaximal vasoconstriction by phenylephrine. Histological investigation was performed using light microscope. Acetylcholine-induced vasodilatation was found to be significantly decreased in glycerol, glycerol+amifostine and amifostine groups compared to controls at all concentrations. Reduction in acetylcholine-induced vasodilation was more prominent in amifostine group compared to amifostine+glycerol group. There was histological renal damage in all experimental groups and this damage was more pronounced in glycerol+amifostine group. In conclusion, contrary to expectation, amifostine per se led to histological damage and potentiated the histological damage caused by glycerol and produced a decrease in acetylcholine-induced vasodilatation. The mechanisms by which amifostine exerts its effects are not known.
    Basic &amp Clinical Pharmacology &amp Toxicology 10/2005; 97(3):168-73. · 2.18 Impact Factor
  • Article: Relationship between sleep complaints and proinflammatory cytokines in haemodialysis patients.
    [show abstract] [hide abstract]
    ABSTRACT: Sleep complaints are common in end-stage renal disease. We aimed to investigate the relationship between sleep-related complaints and inflammatory cytokines in haemodialysis (HD) patients, and also the effects of HD on sleep patterns and cytokine levels. Predialysis serum interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) levels in nine patients with sleep complaints were compared with those of nine patients without sleep complaints and nine healthy controls. Patients with sleep complaints underwent polysomnography the night after HD and the following night. Patients with sleep complaints had significantly higher predialysis IL-1beta levels compared with those without and healthy controls (P=0.004 and P=0.000, respectively). They also had higher predialysis IL-6 and TNF-alpha levels than those without sleep complaints; however, the difference was not significant. Patients without sleep complaints had higher mean IL-6 and TNF-alpha and similar mean IL-1beta levels compared with healthy controls (P=0.001, P=0.024, P=0.26, respectively). Obstructive sleep apnoea syndrome (OSAS) was found in six out of nine (66%) patients with sleep complaints. Sleep architecture and cytokine levels did not differ between the two nights. The mean serum IL-1beta, IL-6 and TNF-alpha levels did not differ in the pre- and post-polysomnographic samples. There was no correlation between IL-1beta, IL-6 or TNF-alpha levels and the apnoea-hypopnoea index. Proinflammatory cytokines, IL-1beta in particular, might be associated with sleep complaints in HD patients. OSAS is not uncommon in HD patients with sleep-related complaints and sleep architecture does not appear to be effected by the HD procedure itself.
    Nephrology 09/2005; 10(4):330-5. · 1.31 Impact Factor
  • Article: Effects of Amifostine on Glycerol‐Pretreated Rabbit Kidneys
    [show abstract] [hide abstract]
    ABSTRACT: Glycerol-induced acute renal failure is an experimental model for myoglobinuric nephropathy. Amifostine is a cytoprotective agent which scavenges the free radicals. Since there is enhanced production of reactive oxygen metabolites in glycerol-induced acute renal failure, we wanted to examine whether amifostine has a protective role against vascular reactivity and histological changes in kidneys isolated from glycerol-pretreated rabbits. Perfusion pressure was recorded from kidneys obtained from rabbits injected with glycerol 3 hr before the experiments and from glycerol-pretreated and non-pretreated rabbits injected with amifostine 30 min. before the experiments. Acetylcholine-induced (10−8-10−5 M) vasodilatation was tested following the construction of submaximal vasoconstriction by phenylephrine. Histological investigation was performed using light microscope. Acetylcholine-induced vasodilatation was found to be significantly decreased in glycerol, glycerol+amifostine and amifostine groups compared to controls at all concentrations. Reduction in acetylcholine-induced vasodilation was more prominent in amifostine group compared to amifostine+glycerol group. There was histological renal damage in all experimental groups and this damage was more pronounced in glycerol+amifostine group. In conclusion, contrary to expectation, amifostine per se led to histological damage and potentiated the histological damage caused by glycerol and produced a decrease in acetylcholine-induced vasodilatation. The mechanisms by which amifostine exerts its effects are not known.
    Basic & Clinical Pharmacology & Toxicology 08/2005; 97(3):168 - 173. · 2.18 Impact Factor