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The Effect of Dialysis Modality and Membrane Performance on Native Immunity in Dialysis Patients

Abstract

Chronic Kidney Disease (CKD) is characterized by immune activation with development of chronic inflammation. However, immune deficiency also exists in CKD patients. The number and the activity of Natural Killer cells (NK-cells) are influenced by the biocompatibility of various dialysis membranes. In this study we investigated the effect of dialysis modality and membrane type on NK-cell number and on phagocytic activity of neutrophils in patients on different dialysis methods.

Sixty patients were included in the study and divided in three groups of 20 patients each. Patients on conventional hemodialysis using Low Flux membrane (cHD-LF) were included in Group I, patients on conventional dialysis using High Flux membrane (cHD-HF) were included in Group II and patients treated by on-line hemodiafiltration with High Flux polysulphone membrane (on-line HDF) were included in Group III. Native immunity was investigated using the number of NK-cells and the phagocytic activity of neutrophils.

NK-cells count was significantly lower (p<0.001) in the three groups of dialyzed patients in comparison to healthy subjects. However, no significant difference was observed in the NK-cells count among patients treated by conventional dialysis using Low or High Flux membrane and patients treated by on-line hemodiafiltration. Similarly, although the phagocytic activity of neutrophils was significantly decreased in all patients on dialysis (p<0.001), no difference related to the dialysis modality or membrane performance was observed. A strong positive correlation was recognized between parathormone blood levels and number of NK-cells (r=0.305, p<0.01).

In conclusion, an impairment of the native immunity represented by NK cell number and phagocytic activity of neutrophils is observed in patients on dialysis. Dialysis modality and membrane performance do not influence the native immunity of dialyzed patients. However, parathormone blood levels are possibly involved in the development of immune system disturbances in such patients.

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Pilot Tests and Fouling Identification in the Ultrafiltration of Model Oily and Saline Wastewaters

References [1] Abadi SRH, Sebzari MR, Hemati M, Rekabdar F, Mohammadi T. Ceramic membrane performance in microfiltration of oily wastewater. Desalination. 2011;265:222-228. DOI: 10.1016/j.desal.2010.07.055. [2] Ebrahimi M, Willershausen D, Ashaghi KS, Engel L, Placido L, Mund P, et al. Investigations on the use of different ceramic membranes for efficient oil-field produced water treatment. Desalination. 2010;250(3):991-996. DOI: 10.1016/j.desal.2009.09.088. [3] Jamaly S, Giwa A, Hasan SW. Recent improvements in oily wastewater treatment

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Pervaporative desulfurization of gasoline – separation of thiophene/n-heptane mixture / Perwaporacyjne odsiarczanie benzyny – separacja mieszanin tiofen/n-heptan

Abstract

This paper presents the recent advances in pervaporative reduction of sulfur content in gasoline. Methods of preliminary selection of membrane active layer material are presented. Interactions between gasoline components (typical hydrocarbon and sulfur species) and membranes are showed. Influence of pervaporation process parameters i.e. feed temperature, downstream pressure and feed flow rate on the separation efficiency is discussed. Investigations of the influence of sulfur concentration in fluid catalytic cracking (FCC) gasoline on membrane performance have been conducted. A series of PV tests was carried out to investigate the separation properties of the commercial composite membrane with an active layer made of poly(dimethylsiloxane) and to determine the efficiency of organic sulphur compound (thiophene) removal from model thiophene/n-heptane mixture depending on its concentration.

Open access
Continuous renal replacement therapy allows higher colistin dosing without increasing toxicity

Abstract

Polymyxins are ‘‘old’’ antimicrobials which were abandoned for almost 30 years because of significant renal and neurological toxicity. However, the alarming rise of multi-resistant Gramnegative bacterial infections worldwide has revived interest in these ‘‘forgotten’’ agents. Colistin (polymyxin E) is one of the main antibiotics of this class. It is most often administered as the pro-drug colistimethate sodium. Doses for treatment of systemic infections in adults range between 3 and 9 million IU per day. Colistin is increasingly used for treatment of pneumonia and bacteremia in critically ill patients. During their ICU stay, many of these subjects will need continuous renal replacement therapy (CRRT) because of acute kidney injury or an unstable hemodynamic condition. Based on recent pharmacological data and own experience, we postulate that patients undergoing CRRT may receive substantially higher doses of colistin (i.e., a high loading dose, followed by a maintenance dose up to 4.5 million IU tid). Treatment can be continued for a prolonged time period without increasing toxicity. CRRT counteracts colistin accumulation because the drug is continuously filtered and also significantly adsorbed in the bulk of the dialysis membrane. Implementing such ‘‘CRRT rescue’’ therapy does require the strict use of highly adsorptive dialysis membranes in association with citrate anticoagulation to increase membrane performance.

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Linking process variables and newsprint properties in Mazandaran Wood and paper Industries

. Bioresource Technol. 119, 252-261. 7. Kallioinen, M., Huuhilo, T., Reinikainen, S.P., Nuortila- -Jokinen, J. & Mänttäri, M. (2006). Examination of membrane performance with multivariate methods: A case study within a pulp and paper mill fi ltration application. Chemometr Intell. Lab. 84(1), 98-105. 8. Lahtinen, K. & Kuuipalo, J. (2008). Statistical prediction model for water vapour barrier of extrusion-coated paper. TAPPI J. 9(2008), 8-15. 9. Mercangoz, M. & Doyle, F.J. (2006). Model-based control in the pulp and paper

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Performance and Selectivity of Ceramic Membranes in the Ultrafiltration of Model Emulsion in Saline

References [1] S.R.H. Abadi, M.R. Sebzari, M. Hemati, F. Rekabdar and T. Mohammadi. “Ceramic membrane performance in microfiltration of oily wastewater”, Desalination, vol. 265, no. 1-3, Jan. 2011, pp. 222-228. [2] N.A. Ochoa, M. Masuelli and J. Marchese. “Effect of hydrophilicity on fouling of an emulsified oil wastewater with PVDF/PMMA membranes”, J. Membrane Sci., vol. 226, no. 1-2, Dec. 2003, pp. 203-211. [3] R. Marecik, P. Cyplik and Ł. Chrzanowski. ”Oczyszczanie ścieków rafineryjnopetrochemicznych

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Evaluation of fouling potential of nanofiltration membranes based on the dynamic contact angle measurements

Bruggen, B., (2006). Characterization of polymeric nanofi ltration membranes for systematic analysis of membrane performance. J. Membr. Sci. , 278, 418-427. doi:10.1016/j. memsci.2005.11.027. 15. Boussu, K., Van der Bruggen, B., Volodin, A., Snauwaert, J., Van Haesendonck, C. & Vandecasteele, C. (2005). Roughness and hydrophobicity studies of nanofi ltration membranes using different modes of AFM. J. Colloid Interf. Sci. , 286, 632-638. doi:10.1016/j.jcis.2005.01.095. 16. Nghiem, L.D., Schafer, A.I. & Elimelech, M. (2005). Nanofi

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Optimization of electrocoagulation of instant coffee production wastewater using the response surface methodology

Technology of COD and BOD Reduction from Coffee Processing Wastewater Using Avocado Seed Carbon (ASC). Water, Air, Soil Pollut. 207, 299–306. DOI: 10.1007/s11270-009-0137-2. 7. Qiao, W., Takayanagi, K., Shofie, M., Niu, Q., Yu, H.Q. & Li, Y.Y. (2013). Thermophilic anaerobic digestion of coffee grounds with and without waste activated sludge as co-substrate using a submerged AnMBR: System amendments and membrane performance. Bioresour. Technol. 150, 249–258. DOI: 10.1016/j.biortech.2013.10.002. 8. Benincá, C., Vargas, F.T., Martins, M.L., Gonçalves, F.F., Vargas

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Evaluation of effectiveness of natural organic compounds removal from water in hybrid processes

., K onieczny K., R ajca M. 2005. Hybrid membrane processes for the removal of contaminations from natural water. Monographs of Environmental Engineering Committee of Polish Academy of Sciences. Vol. 32 pp. 143. C ai Z., K im J., B enjamin M.M. 2008. NOM removal by adsorption and membrane filtration using heated aluminum oxide particles. Environmental Science and Technology. Vol. 42. Iss. 2 p. 619–623. K absch -K orbutowicz M., B iłyk A., M ołczan M. 2006. The effect of feed water pretreatment on ultrafiltration membrane performance. Polish

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The application of ultrafiltration for separation of glycerol solution fermented by bacteria

.F. & Bénézech, T. (2004). The effect of multiple fouling and cleaning cycles on a tubular ceramic microfiltration membrane fouled with a whey protein concentrate. Membrane performance and cleaning efficiency, Food Bioproducts Process , 82 (C3), 231-243. DOI: 10.1205/ fbio.82.3.231.44182. 25. Cabero, M.L., Riera, F.A. & Alvarez, R. (1999). Rinsing of ultrafiltration ceramic membranes fouled with whey proteins: effects on cleaning procedures, J. Membr. Sci . 154, 239-250. DOI: 10.1016/S0376-7388(98)00294-4. 26. Bachin, P., Aimar, P. & Field, R

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