Effect of Copper and Zinc Ions on Biochemical and Molecular Characteristics of Calcium Oxalate Renal Stones: a Controlled Clinical Study.

Contradictory results are existed in the literature regarding the impact of trace elements on the pathogenesis of calcium oxalate (CaOx) stone patients. Therefore, the aim of our study was to investigate the effect of Cu and Zn on biochemical and molecular characteristics of CaOx stones. Plasma and urine concentrations of Cu and Zn in 30 CaOx stones patients and 20 controls were determined by flame atomic absorption spectrometry (FAAS). Urinary levels of citric acid and oxalate were measured by commercial spectrophotometric kits. Blood levels of glutathione reduced (GSH) and catalase (CAT) were determined as markers of antioxidant activity, while blood malondialdehyde (MDA) and urine level of nitric oxide (NO) were used to assess oxidative stress. Gene expression of MAPk pathway (ERK, P38, and JNK) were estimated. The plasma and urine levels of Cu were significantly increased in the patient group compared to those of controls, while the levels of Zn were decreased. Excessive urinary excretion of citric acid and oxalate were found among CaOx stone patients. The GSH and CAT concentration were significantly reduced in CaOx stones patients compared to healthy group. The plasma MDA and urine NO concentration were significantly increased in CaOx stones patients compared to control group. The expressions of the studied genes were significantly increased in CaOx stones patients. These findings suggest that alteration in Cu and Zn might contribute to pathogenesis of CaOx patients through oxidative stress and MAPK pathway genes (ERK, P38 and JNK).

Does the Presence of Heavy Metals Influence the Gene Expression and Oxidative Stress in Bladder Cancer?

Heavy metal toxicity is associated with cancer progression. Studies have reported the relation between some metal ions and bladder cancer (BC). Direct influence of such agents in bladder carcinogenesis is still needed. Total 49 BC patients were included in the study. Level of Pb, Cr, Hg and Cd, oxidative stress markers, and gene expression of Bcl-2, Bax, IL-6, AKT, and P38 genes were detected in cancer and non-cancerous tissues obtained from bladder cancer patients. Concentrations of Pb, Cr, and Cd were significantly elevated in cancer tissues than normal, while Hg level was significantly increased in normal tissue than cancer. MDA level was significantly higher and SOD activity was lower in the cancer tissues compared to non-cancerous. The expressions of Bcl-2, IL-6, AKT, and P38 were significantly increased in the cancer tissues than in normal tissues while Bax level was significantly increased in non-cancerous tissue than in cancer tissue. In cancer tissue, there were significant correlations between Cr level with expression of Bax, AKT, and P38 while Cd level was significantly correlate with Bax, IL-6, AKT, and P38expression. The correlation between Cr and Cd with the expression of Bax, IL-6, AKT, and P38 may indicate a carcinogenic role of these metals on progression of bladder cancer.

The Ideal Interval Between Repeated Shockwaves Lithotripsy Sessions for Renal Stones: A Randomized Controlled Trial.

Objectives: To assess the ideal interval between repeated extracorporeal shockwave lithotripsy (SWL) for renal stones. Patient and Methods: Eligible patients with a single renal stone ≤20 mm who required SWL were randomly assigned to one of three groups based on intervals between first and second sessions. Patients underwent the second session after 3, 7, and 14 days in Groups 1, 2, and 3, respectively. Tubular functions were assessed through comparisons of urinary execration of kidney injury molecule-1 (KIM-1), neutrophil gelatinase associated lipocalin (NGAL), and interleukin-18 (IL-18) with pre-SWL values, whereas glomerular function was assessed by comparisons of protein/creatinine ratio with pre-SWL and changes in ipsilateral renal function on isotope scans. Treatment success was assessed by noncontrast CT after 3 months. Results: All demographics of the 166 patients included in the study were comparable between the three groups. There were significant elevations of tubular biomarkers and protein/creatinine ratio after first and second SWL sessions compared with pre-SWL values (p < 0.0001). All tubular biomarkers returned to pre-SWL values at 7 and 14 days after second session, whereas they remained significantly elevated 3 days after second session (p = 0.027, < 0.001 and <0.001 for KIM-1, NGAL, and IL-18, respectively). SWL success was 73.6% in Group 1, 83.7% in Group 2, and 81% in Group 3. A significant decrease in ipsilateral renal split function was observed in Group 1 at the 3-month follow-up. Conclusions: An interval of 7 days is required between SWL sessions when treating renal stones to allow for complete recovery of kidney functions. Clinical Trial Registration: ID: NCT04575480.

Spectrophotometric determination of trace vanadium in fresh fruit juice samples by ion pair-based surfactant-assisted microextraction procedure with solidification of floating organic drop.

An ion pair-based surfactant-assisted dispersive liquid-liquid microextraction with solidification of floating organic drop (IP-SA-DLLME-SFOD) was developed for extraction of vanadium followed by spectrophotometric determination. Tannic acid (TA) and cetyl trimethylammonium bromide (CTAB) were utilized as complexing and ion-pairing agents, respectively. Using ion-pairing, TA-vanadium complex became more hydrophobic and quantitatively extracted into 1-undecanol. Some factors that influence extraction efficiency were studied. Under optimized circumstances, the detection and quantification limits were 1.8 µg L-1 and 5.9 µg L-1, respectively. The method was linear up to 1000 µg L-1 and the enrichment factors was 19.8. For 100 µg L-1 vanadium, the intra-day, and inter-days relative standard deviations (n = 8) were 1.4% and 1.8%, respectively. The suggested IP-SA-DLLME-SFOD procedure has been effectively implemented for spectrophotometric quantification of vanadium in fresh fruit juice samples. Finally, the greenness of the approach was estimated using Analytical Greenness Calculator (AGREE), which proved its environmental friendliness and safety.

Biogeochemical behaviour and toxicology of chromium in the soil-water-human nexus: A review.

Chromium (Cr) affects human health if it accumulates in organs to elevated concentrations. The toxicity risk of Cr in the ecosphere depends upon the dominant Cr species and their bioavailability in the lithosphere, hydrosphere, and biosphere. However, the soil-water-human nexus that controls the biogeochemical behaviour of Cr and its potential toxicity is not fully understood. This paper synthesizes information on different dimensions of Cr ecotoxicological hazards in the soil and water and their subsequent effects on human health. The various routes of environmental exposure of Cr to humans and other organisms are also discussed. Human exposure to Cr(VI) causes both carcinogenic and non-carcinogenic health effects via complicated reactions that include oxidative stress, chromosomal and DNA damage, and mutagenesis. Chromium(VI) inhalation can cause lung cancer; however, incidences of other types of cancer following Cr(VI) exposure are low but probable. The non-carcinogenic health consequences of Cr(VI) exposure are primarily respiratory and cutaneous. Research on the biogeochemical behaviour of Cr and its toxicological hazards on human and other biological routes is therefore urgently needed to develop a holistic approach to understanding the soil-water-human nexus that controls the toxicological hazards of Cr and its detoxification.

Relation between blood levels of heavy metals and some markers of oxidative stress among boys with neuropathic bladder and posterior urethral valve.

BACKGROUND: The status of heavy metals in children with lower urinary tract pathology that may harm the upper tract, e.g., neuropathic bladder and posterior urethral valve and its relationship with oxidative stress has not been adequately investigated. Therefore, the object of the current work was to evaluate the concentrations of copper, zinc, cadmium and lead and their relations with levels of catalase (CAT), malondialdehyde (MDA) and glutathione (GSH) in boys with neuropathic bladder and posterior urethral valve. METHODS: Thirty-six children with neuropathic bladder, 35 children with posterior urethral valve and 33 health controls were included in the study. In addition to routine laboratory tests, blood samples were collected from patients and controls to assess levels of Cu, Zn, Cd and Pb in addition to plasma concentrations of CAT, MDA and GSH. RESULTS: Significantly elevated levels of Cu, Pb, CAT, MDA and GSH and significantly lower concentration of blood Zn were found in the studied groups compared to the controls. In the posterior urethral valve group, blood level of Cu was positively correlated with GSH while a significantly negative relation was observed between blood Zn and CAT activity among the neuropathic bladder patients. CONCLUSION: Neuropathic bladder and posterior urethral valve may lead to abnormalities in the blood levels of heavy metals (i.e. Cu, Pb and Zn) and markers of oxidative stress (CAT, MDA and GSH). Therefore, the levels of theses metal ions should be monitored during the treatment course of neuropathic bladder and posterior urethral valve patients to prevent or minimize long-term oxidative injury.

Electrochemical sensing of sodium dehydroacetate in preserved strawberries based onin situ pyrrole electropolymerization at modified carbon paste electrodes.

Sodium dehydroacetate (SDA) is one of the most common additives and preservatives in food, especially for strawberries, due to its fungicidal and antibacterial effects. Therefore, an innovative electrochemical sensor, depending on carbon paste electrode (CPE) modulated with multi-walled carbon nanotubes and molecularly imprinted polymers, was constructed for in situ detection of SDA. Based on density functional theory calculations, the polymer film was imprinted on the modified CPE surface via electrochemical polymerization of pyrrole in the presence of SDA. The morphology and electrochemical behavior of the synthesized sensors were characterized using different techniques. Under optimal conditions,a wide linear range (4.1 × 10-6 -1.2 mM)with a detection limit of 0.13 nM was obtained using differential pulse voltammetry and electrochemical impedance spectroscopy. The proposed sensor displayed superb selectivity for SDA, good precision (RSD = 2.7%), and high stability (˃4 weeks). Thus, it was successfully applied to determine SDA in strawberry samples with excellent recoveries (96.7%-100%).

A critical review of selected preconcentration techniques used for selenium determination in analytical samples.

Selenium (Se) is considered to be an essential trace element needed for all living organisms. The importance, deficiency, and toxic effects of Se mainly depend on its quantity and chemical nature. It has been observed that the inorganic versions of Se are more hazardous than the organic versions. This review is mainly focused on the application of different extraction methods used for Se extraction and determination such as microextraction, solid-phase extraction (SPE), and their modified modes in the last 12 years. The use of different dispersive medium (magnetic field, ultrasonic radiation, and vortex agitator) to enhance Se separation is also part of this review. The usage of environmentally friendly solvents such as supramolecular solvents, hydrophobic deep eutectic solvents (DESs), and ionic liquids (ILs) are also the focus of attention in this review. This review is also emphasized the application of advanced microextraction methods, particularly liquid-phase microextraction (LPME). The most recent advances in LPME extraction techniques for Se in various environmental samples, as well as their prospects, are reviewed. Additionally, a summary of cheap, simple, and accurate techniques that have not yet been used to determine small amounts of Se has been provided.

Air-assisted cloud point extraction coupled with inductively coupled plasma optical emission spectroscopy for determination of samarium in environmental samples.

For the first time, air-assisted cloud point extraction (AACPE) was presented to preconcentrate metal ions. The procedure was conjugated with inductively coupled plasma-optical emission spectroscopy for determination of samarium. In this procedure, samarium ions were complexed with aluminon and extracted into Triton X-114 in the presence of potassium iodide. The mixture was repeatedly sucked and dispersed with a syringe (three times) to create cloud solution. Experimental factors that affect the extraction competence of the AACPE procedure, such as pH, amount of aluminon and Triton X-114, salt addition, number of suction/injection cycles, and centrifugation rate and time, have been investigated and optimized. A linear calibration curve from 0.2 to 200.0 µg L-1 with enrichment factor and detection limit of 102 and 0.06 µg L-1, respectively, was established under the optimum experimental conditions. The approach was used to determine samarium in wastewater and rock samples, with recoveries ranging from 98% to 99%.

Applications of electrochemical techniques for determination of anticoagulant drug (Rivaroxaban) in real samples.

The electrochemical behavior of rivaroxaban (RIV), a direct Factor Xa inhibitor, was investigated using a glassy carbon electrode (GCE) based on molecularly imprinted polymer (MIP). The MIP was developed by co-polymerization of different monomers (acrylamide and methacrylic acid) with the cross-linker (ethylene glycol dimethacrylate (EGDMA)) in the presence of initiator (potassium persulphate) and RIV as a template. Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), energy dispersive X-ray (EDX), and scanning electron microscope (SEM) were used for the characterization of the fabricated polymers. To prepare the potentiometric sensor, the MIP was incorporated in polyvinyl chloride (PVC) in the presence of a plasticizer and coated on the GCE as one layer. While the voltammetric sensor was prepared by drop coating technique, in which the graphene oxide and MIP were deposited on the bare GCE, respectively. Linear response over RIV concentrations in the range of 1.2 × 10-9 - 1 × 10-3 mol L-1 and 5.4 × 10-11 - 3.1 × 10-3 mol L-1 with detection limits of 2.4 × 10-10 mol L-1 and 2.3 × 10-12 mol L-1 were achieved for potentiometric and voltammetric sensors, respectively. Both sensors have high precision, selectivity, and good stability. Due to the abovementioned merits, both sensors were successfully applied for the detection of RIV in different blood samples and in pharmaceutical tablets, and acceptable mean recoveries (99.3-100.3%) were obtained.

Gene expression and oxidative stress markers profile associated with toxic metals in patients with renal cell carcinoma.

BACKGROUND: Toxic metals are associated with cancer progression. Studies have reported the relation between some toxic metals and renal cell carcinoma (RCC). METHODS AND RESULTS: Blood levels of Cd and Pb were determined in 94 RCC patients (RCC group) and 91 matched controls as well as blood level of malondialdehyde (MDA) and catalase (CAT) activity as markers of oxidative stress and antioxidant, respectively. Gene expression of MAP kinase pathway (P38 and JNK), hypoxia-inducible factor 1-alpha (HIF1α), vascular endothelial growth factor (VEGF), cytochrome C oxidase subunit 6 (COX6), metallothionein (MT2A), and heat shock protein (HSP90AA1) were evaluated in the obtained tissue specimens. Blood Cd and Pb levels were significantly higher in RCC group comparing to control group with preferential significant increase of Cd in chromophobe RCC (chRCC) sub-type. MDA level was significantly higher and CAT activity was lower in the RCC compared to controls. The difference was evident only in chRCC. The expressions of genes were significantly increased in the cancer tissues than in non-cancerous tissues in RCC sub-types and there was a significant correlation between Cd levels and expression of genes VEGF, MT2A, P38 and JNK in chRCC group. Immunohistochemical staining of clear cell RCC tissues shows a marked expression of VEGF and HIF-1α.While COX6 staining show marked expression in chRCC. CONCLUSIONS: There is a positive correlation between Cd toxicity and the development of RCC, especially chRCC sub-type. Cd is strongly incriminated in the pathogenesis of chRCC through the effort on some genes and oxidative stress markers.

Chemical composition of Zamzam water: A comparative study with international standards of drinking water.

Studies conducted on the chemical composition of Zamzam water are conflicting especially for arsenic. Therefore, the aim of our study is to study the composition of tap and bottled Zamzam water and to compare its quality according to international guidelines of drinking water. Six Zamzam tap water samples as well as one bottled sample were analyzed according to standard methods (APHA) for their chemical constituents (pH, TDS, Na, K, Mg, Ca, Fe, Cu, Zn, Cd, Pb, Mn, Al, As, Cl-, SO4 -2, HCO3 - and PO4 -3). The results were compared to guidelines of WHO and EPA for quality of drinking water. All analyzed parameters were below the maximum allowable limits (MAL) of WHO and EPA (p˃0.05), with the exception of TDS. The average values of TDS (814 mg L-1 in tap zamzam water samples and 812 mg L-1 in bottled sample) were below the MAL of WHO (1000 mg L-1) but exceeded the limit that defined by EPA as a non-enforceable guidelines (500 mg L-1) (p˂0.05). Compared to the collected tap zamzam water samples, bottled sample had significantly lower levels of Na, PO4 -3 (p˂0.05) and Cu (p˂0.01). The study concluded that Zamzam water has acceptable chemical composition including arsenic, except for TDS that exceeds the high non-enforceable accepted limit according to EPA.

Chemically modified rice husk as an effective adsorbent for removal of palladium ions.

Bio-matrix of rice husk and Mobil Composition of Matter No. 41 (MCM-41) was modified with alizarin red S for preconcentration of Pd2+ prior flame atomic absorption spectrometric determination. The prepared bio-matrix (RH@MCM-41@ARS) was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope, energy dispersive X-ray spectrometer (SEM/EDX) and surface area studies. The impact of different parameters (solution pH, amount of sorbent, contact time, sample volume, initial Pd2+ concentration and diverse ions) on the uptake of Pd2+ were evaluated. The maximum adsorption capacity of Pd2+ onto RH@MCM-41@ARS was 198.2 mg g-1 at optimum conditions. Applying the optimized procedure as a preconcentration step led to limit of detection of 0.13 µg L-1 and dynamic analytical range up to 500 µg L-1. The sorbent was regenerated by 0.5 mol L-1 thiourea for at least 10 cycles without significant reduction of adsorption capacity. The method was applied for preconcentration of Pd2+ from real samples.

Correlation between blood levels of cadmium and lead and the expression of microRNA-21 in Egyptian bladder cancer patients.

OBJECTIVE: To investigate the relationship between blood levels of cadmium (Cd) and lead (Pb) and the expression of miRNA-21 among bladder cancer (BC) patients. MATERIAL AND METHODS: The blood concentrations of Cd and Pb in 268 BC patients and 132 controls were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The blood concentrations of Cd and Pb were interpreted according to the type and stage of the carcinoma. The expression of miRNA-21 was assessed by quantitative reverse transcription polymerase chain reaction in cancerous and adjacent non-cancerous bladder tissues among the patient groups. RESULTS: The blood concentrations of Cd and Pb were statistically elevated in BC patients compared to those of the controls. This elevation is more prevalent in groups with muscle-invasive bladder cancer (MIBC) than those with non-muscle invasive bladder cancer (NMIBC). Among the BC group, miRNA-21 was upregulated in cancerous tissues relative to adjacent non-cancerous tissues. Moreover, the expression was significantly higher in patients with MIBC compared to those with NMIBC. The expression of miRNA-21 in cancerous tissues was significantly associated with blood concentration of Cd and Pb among BC patients. CONCLUSION: There is a relationship between Cd and Pb body burden and the tissue expression of miRNA-21 among BC patients. This indicates the role of miRNA-21 in Cd and Pb induced BC.

Preventive effect of pomegranate juice against chemically induced bladder cancer: An experimental study.

OBJECTIVES: Pomegranate juice (PJ) is rich in important compounds with anti-cancer activities. This study aims to investigate the preventive effect of pomegranate juice (PJ) against bladder cancer (BC). METHODS: Eighty male Sprague Dawley rats were randomly classified into 4 equal groups: (1) Normal controls; (2) PJ group: supplied by PJ for 12 weeks; (3) Cancer-induced group: intake 0.05% v/v N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) for 8 weeks; (4) Cancer-prevented group: BBN + PJ. After 12 weeks, all rats were sacrificed and their urinary bladder tissues were subjected to histopathological and immunohistochemical (p53) examinations, expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), hypoxia-inducible factor 1 (HIF-1) and the tumor protein p53 (TP53) and analysis of oxidative stress markers. RESULTS: The development of BC was: 0/20 (0%) in normal, PJ and cancer-prevented groups and 20/20 (100%) in cancer-induced group. Significant neoplastic lesions were observed in cancer-induced group. Mild preneoplastic alterations were noticed in 25% (5/20) of cancer-prevented group. p53 immunostaining were significantly elevated in the cancer-induced group, which was decreased in the cancer-prevented group. The relative expressions of IL-6, TNF-α, HIF-1 and TP53 were significantly lower in the cancer-prevented group compared to the cancer-treated group. Correction in the oxidative stress markers were also observed in the cancer-prevented group. CONCLUSION: PJ possesses a promising inhibitory effect on BC development, probably due to its anti-oxidant and anti-inflammatory properties.

Copper and zinc levels in plasma and cancerous tissues and their relation with expression of VEGF and HIF-1 in the pathogenesis of muscle invasive urothelial bladder cancer: a case-controlled clinical study.

To evaluate Cu and Zn levels in bladder cancer (BC) patients and their relationship with expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1 (HIF-1). Plasma levels of Cu and Zn were determined in 66 transitional bladder cell carcinoma patients (BC group) and 60 matched controls. The concentration of Cu and Zn as well as the expressions of both VEGF and HIF-1 were also estimated in cancerous and non-cancerous bladder tissues in the BC group. The results showed that plasma Cu and Cu/Zn ratio were significantly higher in BC group when compared with the control group. In contrast, the plasma Zn in BC group was significantly lower than in the controls. Comparing levels of Cu and Zn in cancerous and non-cancerous bladder tissues among the BC group indicated a significantly higher Cu levels in the cancerous tissues, while Zn levels was significantly lower. There were higher expressions of both VEGF and HIF-1 in the cancerous samples. Moreover, the Cu concentration in cancerous tissues was significantly correlated with expressions of VEGF and HIF-1. Logistic regression analysis revealed that the increase in plasma Cu/Zn ratio and plasma Cu and the decrease in plasma Zn may be risk factors for development of bladder cancer. We concluded that alteration of plasma and bladder tissue levels of both Cu and Zn is correlated with pathogenesis of bladder cancer. The increase in Cu level in cancerous tissues of BC group has an important role in angiogenesis in bladder cancer cells.

Preconcentration of Lead in Blood and Urine Samples Among Bladder Cancer Patients Using Mesoporous Strontium Titanate Nanoparticles.

In this work, mesoporous strontium titanate nanoparticles (SrTiO3 NPs) were synthesized through a single-step combustion process and were characterized by FT-IR, XRD, SEM-EDX, and TEM. The effects of main parameters that may influence the extraction process (i.e., pH, sorbent amount, time of extraction, eluting agent, and the presence concomitant ions) were investigated. The optimum extraction was achieved at pH 6, 50 mg of sorbent, 20-min shaking time, and 4.0 mL of 0.1 mol L-1 thiourea as desorption agent. Under these conditions, the maximum adsorption capacity was 155.6 mg g-1 with a preconcentration factor of 250 (for a 1000 mL sample solution). The calibration graph was linear up to 1000 µg L-1 and the limit of detection was 1.75 µg L-1. The precision (as relative standard deviation) was 2.53% (n = 10). The procedure was employed for the preconcentration of Pb2+ from blood and urine samples of bladder cancer patients before its determination by FAAS.

Does nitrite and nitrate levels in drinking water impact the health of people in Dakahlia governorate, Egypt?

A total of 1291 drinking water samples were examined for nitrite and nitrate during 6 months from December, 2015 to May, 2016 at 17 cities of Dakahlia governorate (Nile Delta, north of Egypt), and the results were utilized for assessment of health risk of the exposure from drinking water by calculating average daily intake (ADI), hazard quotient (HQ), and the hazard index (HI). The nitrite and nitrate in drinking water had a concentration range of 0.030-0.113 and 2.41-8.70 mg L-1, with mean values of 0.059 ± 0.014 and 5.25 ± 1.61 mg L-1, respectively. Nitrite and nitrate levels in rural areas and ground water samples were significantly higher than that in the urban ones. None of the analyzed samples exceeded WHO guideline values that set out to prevent methemoglobinemia. The values of HQ and HI for all age groups do not exceed unity indicating a low risk of methaemoglobinaemia for the population in this area. Results of the present study indicate that there is no health risk of residents from nitrite and nitrate through drinking water in the studied area. However, the other sources of exposure to nitrite and nitrate should be investigated in further studies.

Solid Phase Extraction and Preconcentration of Trace Gallium, Indium, and Thallium Using New Modified Amino Silica.

Amino silica gel functionalized with 2-hydroxy-5 -(2-hydroxybenzylideneamino)benzoic acid was synthesized, characterized and used as adsorbent for the removal of Ga3+, In3+ and Tl3+ from aqueous solution prior to their determination by flame atomic absorption spectrometry. Experimental parameters that affect the separation process were investigated in both batch and column modes. The maximum adsorption capacities of the sorbent are 61.7 mg g-1, 81.3 mg g-1 and 133.0 mg g-1 for Ga3+, In3+ and Tl3+, respectively. The preconcentration factor is 200 and the limits of detection of Ga3+, In3+ and Tl3+ are 4.10 µg L-1, 1.55 µg L-1 and 1.21 µg L-1, respectively. Interference by Al3+ can be masked by the addition of F-; and that of Fe3+ by its reduction to Fe2+ using 10% ascorbic acid. The method was successfully applied for the determination of these ions in water, sediments and liquid crystal display samples.

Impact of dialyzer membrane flux on metal clearance in hemodialysis patients.

Deficiency of essential trace elements (such as Cu or Zn) and accumulation of potentially toxic trace elements (as Cd or Pb) are both known to have adverse effects in hemodialysis (HD) patients. Up to our knowledge, no studies about the permeability of low and high flux polysulfone membranes on metal ions during hemodialysis are available. Therefore, the aim of the present study was to address this issue. Forty one hemodialysis patients (19 were using high flux polysulfone membrane while the remaining were using low flux one) participated in the study. Blood levels of Cu, Zn, Cd and Pb were determined by graphite furnace atomic absorption spectrometry among HD patients, before and after dialysis session, as well as among matched 40 healthy persons. Blood concentrations of Cu and Zn in the whole hemodialysis group was significantly lower than those of the healthy control group, on the other hand the toxic metals (Cd and Pb) levels were observed to be significantly higher among HD patients compared to the normal persons. Among the hemodialysis group, there were no significant differences between the low and high flux dialyzer groups in terms of pre-dialysis blood levels of Cu, Zn, Cd and Pb. In addition, significantly decreased levels of all metal ions were observed after dialysis sessions using either low or high flux membranes. An exception was Pb which did not show any difference between pre-dialysis and post-dialysis values in the low flux groupIn conclusion Zn and Cu deficiencies should be considered in the treatment of these patients. High flux membranes are more efficient than low flux ones in removing excess Cd and Pb. Therefore, when high flux membranes are used, chelation therapy might not be required for Cd and Pb overload.