Blood filtration

SCHEME 3.5 Blood filtration, reabsorption, and excretion in the nephron... 

A short report (K2) has appeared in which an automatic titrator has been used in a modified version of the Schales and Schales procedure (S2). In the modified method which employs 3 ml of a 1 10 blood filtrate, the standard mercuric nitrate in nitric acid is used as a titrant. The recovery values reported are sufficiently accurate for clinical use ... 

The kidney and bladder are very important in toxicology because they are the main route of elimination of hydrophilic toxicant metabolites and because damage to them in the form of impaired kidney function or bladder cancer is one of the major adverse effects of toxicants. The kidney plays a key role in maintaining body homeostasis. The basic unit of the kidney, through which the organ performs its crucial blood filtration action, is the nephron. As the main organ through which fluid is lost from the body, it is vital in the maintenance of extracellular fluid volume. It acts to maintain... 

A similar approach with multiple columns operating as automated multi-dimensional LC has also been reported by Machtejevas et al. for peptides from human blood filtrate [101],... 

Machtejevas E, John H, Wagner K, Standker L, Marko-Varga G, Forssmann WG, Bischoff R, Unger KK (2004) Automated multi-dimensional liquid chromatography sample preparation and identification of peptides from human blood filtrate. J Chromatogr B 803 121-130... 

Kidney Renal failure Endothelial Hollow fiber Support device, replacement Blood filtration, homeostasis maintenance [31]... 

Polysulfone hollow fibers are usually asymmetric in cross-section, with either an internal skin (for use in blood filtration) or an external skin (for use in gas separation). The ability to form asymmetric structures with divergent permeabilities attributable to the skin and supporting structures makes glassy polymers, such as the polysulfones, attractive for use in the development of separation devices. In contrast to membranes having a uniform cross-section, these asymmetric structures permit much higher filtration rates with equivalent sieving spectra. 

Any discussion of cirrhosis must be based on a Arm understanding of hepatic anatomy and vascular supply. Conceptually, the liver can be thought of as an elaborate blood filtration system receiving blood... 

A report describes 8 patients receiving ACE inhibitors and blood transfusions through bedside leucoreduction filters who experienced severe hypotensive reactions. The reactions were attributed to bradykinin generation during blood filtration and prevention of bradykinin breakdown due to the ACE inhibitors. Six of the patients tolerated subsequent transfusions, but 3 had discontinued their medication the day before the planned transfusion and one received washed (plasma-depleted) components. One patient experienced a second reaction, but then received washed red cells and had no reaction. ... 

Microfilters, Fig. 1 Left. (a) schematic and (b) picture of a microfiuidic blood filtration device [32]. The top and bottom pieces are made up of PDMS, and the membrane is a commercially available hydrophilic polypropylene filter. Right, schematic of another device fabricated similarly but with multiple layers of nanoporous membranes [33]... 

Thorslund S et al (2006) A hybrid poly(dimethyl-siloxane) microsystem for on-chip whole blood filtration optimized for steroid screening. Biomed Microdev 8 73-79... 

ThOTslnnd S, Bergquist J (2006) A hybrid poly (dimethylsiloxane) microsystem for on-ehip whole blood filtration optimized fen steroid screening. Biraned Microdeviees 8 73—79... 

Figure 6.5 Schematic representation of the on-line comprehensive two-dimensional HPLC system including an integrated sample preparation step [32]. Reprinted from Journal of Chromatography B, 803, Machtejevas, E., John, H., Wagner, K., Standker, L, Marko-Varga, C., Forssmann, W.C., Bischoff, R., Unger, K.K., Automated Multi-Dimensional Liquid Chromatography Sample Preparation and Identification of Peptides from Human Blood Filtrate, I2I 130. Copyright (2004), with permission from Elsevier...

Effectiveness of blood filtration is determined by the glomerular filtration rate (GFR), which is affected by the perfusion to the kidneys and other factors. 

GSH as referred to in this paper represent the total sulfhydryl content measured in a protein-free blood filtrate. 

PET track etched membranes are manufactured of thin polymer films irradiated by heavy ion beam (23). Latent tracks of heavy ions in polymer material are treated by chemical ways and as a result, membranes with regular, cylindrical pores with diameter in the range 0.1-3 pm and pore density between 10 to 6x10 pores/cm are obtained (Figure 4. 4). Typical applications of PET membranes are analytical methods, water analysis, general filtration (particles and bacteria removal, chromatography sample preparation), microorganism analysis, blood filtration and microscopy (24)... 

Blood filtration is another application area, since PBT is a good candidate for use as a filter - thanks to its outstanding wettability and fine fiber size. Leukocyte filters for filtering erythrocytes and thrombocyte concentrates as well as whole blood are becoming more important in daily hospital use. An illustration of a typical blood filter used during open-heart surgery can be found in literature. PBT can be effectively sterilized, which renders it suitable for other medical applications [71]. 

Nonwoven fabrics are widely used in various filtration processes in medical and healthcare sectors. Blood filtration is usually used in transfusion therapy, in which... 

The two special filtration mechanisms, sieving and bridging, in the blood filtration process are explained below, and the other five filtration mechanisms can be seen in Section 6.3. 

Most models currently available for blood filtration are based on empirical models/ Bruil proposed a mathematical model for leucocyte filtration process and could explain the filtration law in the plain membrane filter. However, the effect of direct interception in blood filtration is not clearly understood, and the particle capture efficiency may be modelled based on an empirical model proposed by Khilar and Fogler"" for Newtonian liquid flow. With the consideration of the further particle capture due to the reduction of the pore sizes and the porosity of filter fabric by particle bridging, pore blockage, and pore closure, a modified Khilar—Fogler model of the particle capture efficiency by Gruesbeck and Collins" may be applied in blood filtration. 

Other models of the filter efficiency for the filtration of solid and liquid parficles in a Newtonian liquid, due to the particle direct interception and additional clogging mechanism, might be usefid in the blood filtration." " ... 

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