Lipid 752 INDEX

Mayzaud, P., Eaton, C.A. and Ackman, R.G. (1976) The occurrence and distribution of octadecapentaenoic acid in a natural plankton population. A possible food chain index. Lipids 11, 858-862. 

LIPOPROTEINS. Blood plasma lipoproteins are prominent examples of the class of proteins conjugated with lipid. The plasma lipoproteins function primarily in the transport of lipids to sites of active membrane synthesis. Serum levels of low density lipoproteins (LDLs) are often used as a clinical index of susceptibility to vascular disease. 

Comprehensive Organic Chemistry , Pergamon, Elmsford, NY, 1979, is a six-volume treatise on the synthesis and reactions of organic compounds. The first three volumes cover the various functional groups, vol. 4, heterocyclic compounds, and vol. 5, biological compounds such as proteins, carbohydrates, and lipids. Probably the most useful volume is vol. 6, which contains formula, subject, and author indexes, as well as indexes of reactions and... 

The parameters K1/ K2/ and K3 are defined by the refractive indices of the crystal and sample and by the incidence angle [32]. If the sample has uniaxial symmetry, only two polarized spectra are necessary to characterize the orientation. If the optical axis is along the plane of the sample, such as for stretched polymer films, only the two s-polarized spectra are needed to determine kz and kx. These are then used to calculate a dichroic ratio or a P2) value with Equation (25) (replacing absorbance with absorption index). In contrast, a uniaxial sample with its optical axis perpendicular to the crystal surface requires the acquisition of spectra with both p- and s-polarizations, but the Z- and X-axes are now equivalent. This approach was used, through dichroic ratio measurements, to monitor the orientation of polymer chains at various depths during the drying of latex [33]. This type of symmetry is often encountered in non-polymeric samples, for instance, in ultrathin films of lipids or self-assembled monolayers. 

The ratio of oleic acid to stearic acid (O/S) is another parameter used for assessing the degree of ageing of a lipid paint binder. This ratio is considered as an index of oxidation because the oleic acid double bond is particularly reactive towards oxidation, so normally the content of oleic acid in aged paintings is very low, with an O/S value around 0.1 0.2 [55]. 

Oxidative damage to membrane polyunsaturated fatty acids leads to the formation of numerous lipid peroxidation products, some of which can be measured as index of oxidative stress, including hydrocarbons, aldehydes, alcohols, ketones, and short carboxylic acids. 

Pentane and ethane (end products of n-6 and n-3 polyunsaturated fatty acid peroxidation, respectively) in expired air are useful markers of in vivo lipid peroxidation. Nevertheless, when gas chromatography is used to measure hydrocarbons, some technical difficulties may be experienced because chromatographic resolution of pentane from isoprene and isopentane is extremely difficult to achieve. Another possible problem could be the presence of these gases as contaminants in atmosphere. Furthermore, the production of hydrocarbon gases depends on the presence of metal ions to decompose lipid peroxides. If such ions are only available in limited amounts, this index may be inaccurate. 

The determination of F2-isoprostanes, oxidation products of arachidonic acid, has been proposed as a more reliable index of oxidative stress in vivo, overcoming many of the methodological problems associated with other markers. The isoprostanes have emerged as a most effective method of quantifying the potential of antioxidants to inhibit lipid peroxidation. However, one drawback of this method is that quantification of F2-iP requires sophisticated techniques, in particular GC/MS and HPLC/MS... 

Colquhoun and Schumacher [98] have shown that y-linolcnic acid and eicosapentaenoic acid, which inhibit Walker tumor growth in vivo, decreased proliferation and apoptotic index in these cells. Development of apoptosis was characterized by the enhancement of the formation of reactive oxygen species and products of lipid peroxidation and was accompanied by a decrease in the activities of mitochondrial complexes I, III, and IV, and the release of cytochrome c and caspase 3-like activation of DNA fragmentation. Earlier, a similar apoptotic mechanism of antitumor activity has been shown for the flavonoid quercetin [99], Kamp et al. [100] suggested that the asbestos-induced apoptosis in alveolar epithelial cells was mediated by iron-derived oxygen species, although authors did not hypothesize about the nature of these species (hydroxyl radicals, hydrogen peroxide, or iron complexes ). 

Thus, the formation of isoprostanes is rightly considered as a unique noninvasive method for the estimation of in vivo lipid peroxidation. However, the use of 8-Ao-PGF2a isoprostane (now known as iPF2a-III) as an index of nonenzymatic in vivo peroxidation has some limitations due to the possibility of its formation by COX-1- and COX-2-catalyzed... 

Leatherland, J.F., R.A. Sonstegard, and M.V. Holdrient. 1979. Effect of dietary mirex and PCB s on hepato-somatic index, liver lipid, carcass lipid and PCB and mirex bioaccumulation in yearling coho salmon, Oncorhynchus kisutch. Comp. Biochem. Physiol. 63C 243-246. 

Weight should be monitored monthly for 3 months, then quarterly. Body mass index, waist circumference, blood pressure, fasting plasma glucose, and fasting lipid profile should be monitored at the end of 3 months, then annually. The use of patient self-assessments are encouraged. 

Using the Mie scattering method, the resonant wavelength shift due to the adsorbed lipid membrane onto the tube wall is simulated with the microtube dimensions identical to the previous simulations. The refractive index of lipid bilayer is assumed to be 1.46. When the inner surface of a tube is coated with lipid membrane, the magnetic field for TE mode can be described in the following form ... 

The results summarized above were obtained by using fluorescence based assays employing phospholipid vesicles and fluorescent labeled lipopeptides. Recently, surface plasmon resonance (SPR) was developed as new a technique for the study of membrane association of lipidated peptides. Thus, artificial membranes on the surface of biosensors offered new tools for the study of lipopeptides. In SPR (surface plasmon resonance) systemsI713bl changes of the refractive index (RI) in the proximity of the sensor layer are monitored. In a commercial BIAcore system1341 the resonance signal is proportional to the mass of macromolecules bound to the membrane and allows analysis with a time resolution of seconds. Vesicles of defined size distribution were prepared from mixtures of lipids and biotinylated lipopeptides by extruder technique and fused with a alkane thiol surface of a hydrophobic SPR sensor. 

The model here consists of a medium 3 (refractive index n3 e.g., glass), a sandwiched layer of thickness t (n2 e.g, polymer, metal, lipid, or more of... 

Abbreviations BSO, D.L-buthionine-. i -sulfoxime L , lipid alkyl radicals LH, lipid LO, Upid alkoxyl radicals LOO, Upid peroxyl radicals L-NAME, yV -nitro-L-arginine-methyl ester MBl, methylene bridge index (mean number of h -aUytic methylene positions per fatty add) NO, nitric oxide NOS, nitric oxide synthase NO, nitrite N02, nitrogen dioxide NO2CI, nitryl chloride O2 , superoxide OH, hydroxyl radical OL, epoxyaUyhc radical OLOO, epoxyperoxyl radical 0=NOO , peroxynitrite SNAP, S-nitroso-iV-acetyl-D.L-penicillamine SOD, superoxide dismutase contd. onp. 98, Subcellular Biochemistry, Volume 36 Phospholipid Metabolism in Apoptosis. 

Figure 7. Relationship of oxidation and degree of polyunsaturation. Polyunsaturation is measured as the methylene bridge index (MBI), which is a more precise measure of extent of unsaturation and oxidizability than the double bond index. It is the mean number of 6is-allylic methylene bridge positions per fatty acid (or fatty acyl chain) in a lipid ensemble. The rate of lipid radical formation measures formation of an oxidative product, while O2 consumption (% O2 lost per sec) is a measure of utilization of a reactant. (Drawn using our data abstracted from Wagner, B.A., Buettner, G.R., and Bums, C.P. 1994, Biochemistry 33 4449-4453).

AmB/lipid ratio (w/w) (%) Mean diameter (nm) Polydispersity index Zeta potential (mV)... 

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