Animal blood plasma

Several mechanisms have evolved to prevent this catastrophe. In bacteria and plants, the plasma membrane is surrounded by a nonexpandable cell wall of sufficient rigidity and strength to resist osmotic pressure and prevent osmotic lysis. Certain freshwater protists that live in a highly hypotonic medium have an organelle (contractile vacuole) that pumps water out of the cell. In multicellular animals, blood plasma and interstitial fluid (the extracellular fluid of tissues) are maintained at an osmolarity close to that of the cytosol. The high concentration of albumin and other proteins in blood plasma contributes to its osmolarity. Cells also actively pump out ions such as Na+ into the interstitial fluid to stay in osmotic balance with their surroundings. 

Abstract. Content of cholesterol in various tissues of experimental animals (blood plasma, thoracal department of aorta, liver microsomes) was increased during atherogenesis depending on the level of aorta impairment. In atherogenesis content of both primary and secondary products of lipid peroxidation was also increased in microsomal membranes of rabbit and mini-pig liver tissue the increase in the rate of microsomal lipid oxidation was accompanied by a decrease in the activity of membrane-bound microsomal 7a-hydroxylase of cholesterol. 

Supercritical fluid CO2 was also investigated for sterilization of dry-powder animal blood plasma containing both living micro-organisms and bacterial endospores (56). The initial water content of the plasma powder was 6.8%. No apparent inactivation of the microbes was achieved at 35°C and 20 MPa in a 2-h treatment. However, with the addition of water (initial water content of 16.7%) and/or the use of cosolvents (ethanol or acetic acid), 2-5 log reductions in living cells could be achieved. The need for water to achieve sterilization of the powders is consistent with previous investigations of sterilization at low water content. 

Furusawa N, Simultaneous high-performace liquid chromatographic determination of sulfamonomethoxine and its hydroxy/N4-acetyl metabolites following centrifugal ultra-filtration in animal blood plasma, Chromatographia 2000 52 653-656. 

Protein-Based Substitutes. Several plant and animal-based proteins have been used in processed meat products to increase yields, reduce reformulation costs, enhance specific functional properties, and decrease fat content. Examples of these protein additives are wheat flour, wheat gluten, soy flour, soy protein concentrate, soy protein isolate, textured soy protein, cottonseed flour, oat flour, com germ meal, nonfat dry milk, caseinates, whey proteins, surimi, blood plasma, and egg proteins. Most of these protein ingredients can be included in cooked sausages with a maximum level allowed up to 3.5% of the formulation, except soy protein isolate and caseinates are restricted to 2% (44). 

Medical Uses. Citric acid and citrate salts are used to buffer a wide range of pharmaceuticals at their optimum pH for stabiUty and effectiveness (65—74). Effervescent formulations use citric acid and bicarbonate to provide rapid dissolution of active ingredients and improve palatabiUty. Citrates are used to chelate trace metal ions, preventing degradation of ingredients. Citrates are used to prevent the coagulation of both human and animal blood in plasma and blood fractionation. Calcium and ferric ammonium citrates are used in mineral supplements. 

Cholesterol is a principal component of animal cell plasma membranes, and much smaller amounts of cholesterol are found in the membranes of intracellular organelles. The relatively rigid fused ring system of cholesterol and the weakly polar alcohol group at the C-3 position have important consequences for the properties of plasma membranes. Cholesterol is also a component of lipoprotein complexes in the blood, and it is one of the constituents oiplaques that form on arterial walls in atherosclerosis. 

Animal cell cultures that are initiated from cells removed directly from the animal are called primary cultures (Figure 2). Primary cultures include both explant cultures (i.e., cultures initiated from small pieces of intact tissue), as well as cultures initiated from preparations of individual or dispersed cells (obtained from intact tissue by mechanical or proteolytic dismption). Nerve fiber explant cultures in blood plasma were among the earliest types of tissue cultures (Harrison, 1907). Cells grow out from such tissue explants and form a single layer of cells completely filling the tissue culture vessel surface. Such cell cultures are called confluent monolayers. Confluent monolayers can then be treated with trypsin, so as to remove the individual cells from the culture vessel surface. The resulting cell suspension is then transferred into other culture containers, so that more viable monolayer... 

Historically, the development of animal cell culture systems has been dependent upon the development of new types of tissue culture media. Mouse L cells and HeLa cells were developed using a balanced salt solution supplemented with blood plasma, an embryonic tissue extract, and/or serum. In 1955 Eagle developed a nutritionally defined medium, containing all of the essential amino acids, vitamins, cofactors, carbohydrates, salts, and small amounts of dialyzed serum (Table 1). He demonstrated that this minimal essential medium (MEM) supported the long-term growth of mouse L and HeLa ceils. Eagle s MEM was so well defined that the omission of a single essential nutrient eventually resulted in the death of these animal cells in culture. 

Carotenoids are also present in animals, including humans, where they are selectively absorbed from diet (Furr and Clark 1997). Because of their hydrophobic nature, carotenoids are located either in the lipid bilayer portion of membranes or form complexes with specific proteins, usually associated with membranes. In animals and humans, dietary carotenoids are transported in blood plasma as complexes with lipoproteins (Krinsky et al. 1958, Tso 1981) and accumulate in various organs and tissues (Parker 1989, Kaplan et al. 1990, Tanumihardjo et al. 1990, Schmitz et al. 1991, Khachik et al. 1998, Hata et al. 2000). The highest concentration of carotenoids can be found in the eye retina of primates. In the retina of the human eye, where two dipolar carotenoids, lutein and zeaxan-thin, selectively accumulate from blood plasma, this concentration can reach as high as 0.1-1.0mM (Snodderly et al. 1984, Landrum et al. 1999). It has been shown that in the retina, carotenoids are associated with lipid bilayer membranes (Sommerburg et al. 1999, Rapp et al. 2000) although, some macular carotenoids may be connected to specific membrane-bound proteins (Bernstein et al. 1997, Bhosale et al. 2004). 

Claims have recently been made61 that the dextran of L. mesenteroides may serve as an efficient substitute for blood plasma. Solutions of partially-hydrolyzed dextran in saline gave favorable results when injected intravenously into experimental animals. Preliminary clinical tests were promising. 

It is interesting to note that pharmacological blockage of NKl receptors also revealed anxiolytic effects in the plus-maze test when mice from the 129/Sv strain (Santarelh et al. 2001), but not from other strains (Rodgers et al. 2004), were used. Thus, the anxiolytic effect of NKl receptor antagonists seems to be more sensitive to effects of the genetic background as compared to benzodiazepines. It is also possible that the relative contribution of the SP-NK1 system in the modulation of anxiety is situation dependent. The basal corticosterone levels in the blood plasma of NKIR and NK1 mice do not differ in low-stress situations, but the increase after the stressful elevated plus-maze test is blunted in the knockout animals (Santarelh et al. 2001). 

In 1847 E. Harless discovered the presence of copper in the blood of the octopus Eledone and the snail Helix pomatia (172, 173). Investigation of the phenomenon by which the blood and tissues of certain marine animals turn blue on exposure to air finally led to the discovery that the blood plasma of such animals contains copper combined with a protein. Because of its analogy to hemoglobin and its ability to carry oxygen, L. Fredericq in 1878 named the copper-containing protein in the blood of Octopus vulgaris hemocyanin (173, 174). 

To appreciate the important and delicate role played by hydrogen in animal life, one need only recall that die pH of die blood plasma never... 

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