Blood red - cell

Nanosilica composed of bioactive nanoparticles can affect the RBC state up to strong hemolysis (erythrolysis) at relatively low concentration of silica C 0.1 wt% (Diociaiuti et al. 1999, Gerashchenko et al. 2002, Blitz and Gun ko 2006). The hemolytic effect of nanosilica can be reduced due to its modification by immobilized polymers (e.g., poly(vinyl pyrrolidone), poly(vinyl alcohol)) or on the use of binary nanooxides such as silica/alumina and silica/titania (Blitz and Gun ko 2006). 

Notice that the greater the content of the second oxide or adsorbed polymer, the lower the hemolytic effect of nanooxides. Changes in the whole RBCs and the RBC membranes interacting with solid nanoparticles can be complex and dependent on component concentrations and conditions (Chuiko 2003, Blitz and Gun ko 2006). 

Nanosilica A-300 (5bet=285 mVg) was used as the initial material. Nanosilica was modified by hexamethyldisilazane to substitute 50% of free surface silanols for trimethylsilyl (TMS) groups. This modification reduces the specific surface area by 15% but the hydrophilic properties practically remain since the heat of immersion in water and Gibbs free energy of the interfacial water layer are close to the corresponding values for the initial silica A-300. 

Rough spicules appear first on the edge of the disk (form 3) and then on the whole RBC surface (forms 4 and 5). 

FIGURE 7.43 Microphotographs of RBCs in the buffer suspension of (a) control sample, and with the presence of (b) 0.1 wt% and (c) 1.0 wt% of unmodified silica A-300. (Adapted with kind permission from Springer Science+Business Media Centr. Eur. J. Chem., Interaction of unmodified and partially silylated nanosilica with red blood cells, 5, 2007c, 951-969, Gun ko, V.M., Galagan, N.R, Grytsenko, l.V. et al.) 

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A number of refinements and applications are in the literature. Corrections may be made for discreteness of charge [36] or the excluded volume of the hydrated ions [19, 37]. The effects of surface roughness on the electrical double layer have been treated by several groups [38-41] by means of perturbative expansions and numerical analysis. Several geometries have been treated, including two eccentric spheres such as found in encapsulated proteins or drugs [42], and biconcave disks with elastic membranes to model red blood cells [43]. The double-layer repulsion between two spheres has been a topic of much attention due to its importance in colloidal stability. A new numeri-... 

Saponins dismpt red blood cells and may produce diarrhea and vomiting. They may also have a beneficial effect by complexing with cholesterol [57-88-5] and thus lowering semm cholesterol levels (24,25). In humans, intestinal microflora seem to either destroy saponins or inactivate them in small concentrations. 

Platelets - Lymphocytes Monocytes " Granulocytes Red blood cells... 

The formed elements consist primarily of red blood cells, ie, erythrocytes. Less than 1 /600 of the total volume of the formed elements is composed of white blood cells, ie, leukocytes, and less than 1/800 are platelets, ie, thrombocytes. Table 1 gives the typical constitution of human blood. 

Primary blood components iaclude plasma, red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes), and stem cells. Plasma consists of water dissolved proteias, ie, fibrinogen, albumins, and globulins coagulation factors and nutrients. The principal plasma-derived blood products are siagle-donor plasma (SDP), produced by sedimentation from whole blood donations fresh frozen plasma (FFP), collected both by apheresis and from whole blood collections cryoprecipitate, produced by cryoprecipitation of FFP albumin, collected through apheresis and coagulation factors, produced by fractionation from FFP and by apheresis (see Fractionation, blood-plasma fractionation). 

Red Blood Cells. Red blood cells (RBC) transport and deUver oxygen and carbon dioxide between the tissues and lungs. Red blood cell transfusions iacrease the oxygen carrying capacity ia anemic patieats. 

Each blood component has specific storage requirements in terms of optimal temperature, additives, expiration, and storage containers. Red blood cells (RBC) from whole blood, provided in 200 mL units, have an expiration of 42 days. Fro2en, deglycerolized RBC, in 170 mL containers, and washed red cells, in 200 mL containers, both expire 24 hours after thawing and washing, respectively leukocyte-reduced RBC, in 200 mL containers, are viable for 24 hours. 

Lead is toxic to the kidney, cardiovascular system, developiag red blood cells, and the nervous system. The toxicity of lead to the kidney is manifested by chronic nephropathy and appears to result from long-term, relatively high dose exposure to lead. It appears that the toxicity of lead to the kidney results from effects on the cells lining the proximal tubules. Lead inhibits the metaboHc activation of vitamin D in these cells, and induces the formation of dense lead—protein complexes, causing a progressive destmction of the proximal tubules (13). Lead has been impHcated in causing hypertension as a result of a direct action on vascular smooth muscle as well as the toxic effects on the kidneys (12,13). 

Lead-induced anemia results from impairment of heme biosynthesis and acceleration of red blood cell destmction (10,13). Lead-induced inhibition of heme biosynthesis is caused by inhibition of S-aminolevulinic acid dehydratase and ferrochelatase which starts to occur at blood lead levels of 10 to 20 pu gjdL and 25 to 30 //g/dL, respectively (10,13). Anemia, however, is not manifested until higher levels are reached. 

The presence of hemoglohin-S (Hb-S) ia red blood cells leads to the formation of Hquid crystalline aggregates iaside the ceU under conditions of low oxygen tension (43,44). The morbid aggregates ultimately arrange themselves iato a gel-like material composed of long fibers that extend the entire length of the ceU and distort its usual shape. 

Cardiac nuclear imaging using Tc -red blood cells can measure the fraction of blood pumped by the heart during each beat. Tc -DTPA and sodium (9-iodohippurate, C H INNaO, are used to measure renal function of the kidney. The enhanced or diminished uptake of... 

A system of internal iron exchange exists which is dominated by the iron required for hemoglobin synthesis. For formation of red blood cells, iron stores can furnish 10—40 mg/d of iron, as compared to 1—3 mg from dietary sources (74). Only ca 10 wt % of ingested iron actually is absorbed. 

Absorption, Transport, and Excretion. The vitamin is absorbed through the mouth, the stomach, and predominantly through the distal portion of the small intestine, and hence, penetrates into the bloodstream. Ascorbic acid is widely distributed to the cells of the body and is mainly present in the white blood cells (leukocytes). The ascorbic acid concentration in these cells is about 150 times its concentration in the plasma (150,151). Dehydroascorbic acid is the main form in the red blood cells (erythrocytes). White blood cells are involved in the destmction of bacteria. 

Fohc acid is a precursor of several important enzyme cofactors required for the synthesis of nucleic acids (qv) and the metaboHsm of certain amino acids. Fohc acid deficiency results in an inabiUty to produce deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and certain proteins (qv). Megaloblastic anemia is a common symptom of folate deficiency owing to rapid red blood cell turnover and the high metaboHc requirement of hematopoietic tissue. One of the clinical signs of acute folate deficiency includes a red and painhil tongue. Vitamin B 2 folate share a common metaboHc pathway, the methionine synthase reaction. Therefore a differential diagnosis is required to measure foHc acid deficiency because both foHc acid and vitamin B 2 deficiency cause... 

The symptoms of vitamin E deficiency in animals are numerous and vary from species to species (13). Although the deficiency of the vitamin can affect different tissue types such as reproductive, gastrointestinal, vascular, neural, hepatic, and optic in a variety of species such as pigs, rats, mice, dogs, cats, chickens, turkeys, monkeys, and sheep, it is generally found that necrotizing myopathy is relatively common to most species. In humans, vitamin E deficiency can result from poor fat absorption in adults and children. Infants, especially those with low birth weights, typically have a vitamin E deficiency which can easily be corrected by supplements. This deficiency can lead to symptoms such as hemolytic anemia, reduction in red blood cell lifetimes, retinopathy, and neuromuscular disorders. 

Ribavirin is not incorporated into the DNA or RNA of either mammalian or viral systems. It has been shown (123), however, that a high dosage of ribavirin given over a prolonged period to Rhesus monkeys results in anemia of red blood cells. This effect is dose related and reversible upon cessation of treatment. Guanosine partially reverses the antiviral effect of ribavirin against certain vimses. 

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