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Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64 ± 0.11 vs 0.42 ± 0.05, p < 0.001). There was a significant negative correlation between CIMT and serum levels of zinc (r = -0.70, p < 0.01), iron (r = -0.71, p < 0.01), and manganese (r = -0.47, p < 0.01), while there was a significant positive correlation between CIMT and serum levels of copper (r = 0.63, p < 0.01), magnesium (r = 0.77, p < 0.01), cobalt (r = 0.63, p < 0.01), cadmium (r = 0.48, p < 0.01), lead (r = 0.38, p < 0.01), and copper/zinc ratio (r = 0.68, p < 0.01). A linear regression analysis showed that serum levels of magnesium, cadmium, lead, and copper/zinc ratio were still significantly and positively correlated with CIMT. We propose that copper/zinc ratio, magnesium and toxic metals cadmium and lead are independent determinants of CIMT in maintenance HD patients without known atherosclerotic disease.

An 87 -year-old female who was undergoing peritoneal dialysis presented with peritonitis caused by Alcaligenes faecalis and Pantoea agglomerans in consecutive years. With the following report we discuss the importance of these unusual microorganisms in peritoneal dialysis patients.

Our data have demonstrated that HD patients exhibit increased oxidative DNA damage and decreased antioxidant activity. We propose that endothelial function is negatively correlated with 8-OHdG/dG ratio and positively correlated with antioxidant enzymes. To our knowledge, this is the first study to demonstrate the inverse relationship between endothelial function and plasma oxidative DNA damage in HD patients.

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Objectives: The aim of the study was to assess the effect of paricalcitol on the experimental contrast-induced nephropathy (CIN) model. We hypothesised that paricalcitol may prevent CIN. Methods: 32 Wistar albino rats were divided into four groups (n58 each): control group, paricalcitol group, CIN group and paricalcitol plus CIN group. Paricalcitol (0.4 mg kg -1 day -1 ) was given intraperitoneally for 5 consecutive days prior to induction of CIN. CIN was induced at day 4 by intravenous injection of indometacin (10 mg kg -1 ), Nv-nitro-L-arginine methyl ester (L-NAME, 10 mg kg -1 ) and meglumine amidotrizoate (6 ml kg -1 ). Renal function parameters, oxidative stress biomarkers, histopathological findings and vascular endothelial growth factor (VEGF) immunoexpression were evaluated. Results: The paricalcitol plus CIN group had lower mean serum creatinine levels (p50.034) as well as higher creatinine clearance (p50.042) than the CIN group. Serum malondialdehyde and kidney thiobarbituric acid-reacting substances levels were significantly lower in the paricalcitol plus CIN group than in the CIN group (p50.024 and p50.042, respectively). The mean scores of tubular necrosis (p50.024), proteinaceous casts (p50.038), medullary congestion (p50.035) and VEGF immunoexpression (p50.018) in the paricalcitol plus CIN group were also significantly lower. Conclusion: This study demonstrates the protective effect of paricalcitol in the prevention of CIN in an experimental model.

Cardiovascular disease (CVD) is the main cause of mortality in hemodialysis (HD) patients. Epicardial fat tissue (EFT) is a new risk factor in CVD. The aim of this study was to evaluate the association between EFT and coronary artery flow reserve (CFR), which is an early indicator of endothelial dysfunction in coronary vessels of HD patients. We performed a cross-sectional study including 71 chronic HD patients and 65 age- and sex-matched healthy controls. Epicardial fat tissue was significantly higher in HD patients when compared to healthy controls (6.53 ± 1.01 mm vs. 5.79 ± 1.06 mm, respectively, P < 0.001). On transthoracic Doppler echocardiography, CFR values were significantly lower in HD patients when compared to healthy controls (1.73 ± 0.11 vs. 2.32 ± 0.28, P < 0.001). Correlation analysis showed CFR values to be inversely correlated with EFT (r = -0.287, P < 0.05). Multiple linear regression analysis was used to define independent determinants of EFT in HD patients. Artery flow reserve, age, body mass index and total cholesterol levels were independently correlated with EFT thickness. This study demonstrated that EFT was significantly higher among HD patients compared to healthy controls. In addition, this study was the first to demonstrate an inverse correlation between EFT and CFR in this patient population.

Oxidative stress is accepted as a nonclassical cardiovascular risk factor in chronic renal failure patients. The aim of this study was to evaluate the relation between oxidative DNA damage (8-hydroxy-2'-deoxyguanosine/deoxyguanosine [8-OHdG/dG] ratio), oxidative stress biomarkers, antioxidant enzymes, and carotid artery intima-media thickness (CIMT) in hemodialysis (HD) patients. Forty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8-OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. CIMT was assessed by carotid artery ultrasonography. 8-OHdG/dG ratios and MDA levels were higher; SOD and GPx activities were lower in HD patients compared to controls. HD patients had significantly higher CIMT compared to controls (0.61 ± 0.08 vs. 0.42 ± 0.05, p < 0.001). There was a significant positive correlation between CIMT and 8-OHdG/dG ratio (r = 0.57, p < 0.01) and MDA levels (r = 0.41, p < 0.01), while there was a significant negative correlation between CIMT and SOD (r = -0.47, p < 0.01) and GPx levels (r = -0.62, p < 0.01). It is firstly demonstrated that CIMT is positively correlated with oxidative DNA damage in HD patients without known atherosclerotic disease.