Mass lipids

Figure 13.4 Low-mass lipid region of the 9.4 T MALDI-FTMS spectrum of...

Fig. 6 (a) Schematics of a polymer-tethered lipid bilayer on a solid support the architecture is composed of a proximal mixed monolayer of lipopolymers and regular low-mass lipids, covered by a monolayer of normal lipids obtained by vesicle fusion. The lipopolymers are covalently attached to the benzophenone-derivative coated substrate by a proton-abstraction reaction as depicted in (b)... 

Low-molar mass lipids have been known for more than 30 years for their ability to self-assemble into vesicles or liposomes, however, with limited overall stability. Polymer membranes, on the other hand, are almost one order of magnitude tougher and at least 10 times less permeable to water than common phospholipids bilayers, due to the increased length and conformational freedom of polymer chains compared to lipids [1]. Biohybrid polymer vesicles combine the toughness of polymers and the biocompatibility of peptides or sugars, making them promising candidates... 

FIGURE 12.3 Effect of different media on cell mass ( ), lipid content ( ), rate of A6-desat-uration of linoleic acid to y-linolenic acid ( ), and percentage of y-linolenic acid in total lipids ([]) in the transformed Y. lipolytica. A6-Desaturation was calculated as [Product]/[Product -i-Substrate] X 100%. Each value point represents the mean of three independent experiments. In each category, values with different letters or numbers are significantly different from each other atp <. 05. 

Lanolin steryl ester determinations Lanolin is the wool grease secreted by the sheep sebaceous glands, and represents a complex mixture of high molecular mass lipids, including fatty acids and alcohols, sterols, hydroxyacids, diols, and aliphatic and steryl esters. Lanolin is widely used in cosmetic and pharmaceutical formulations. The study of minor lipids... 

Figure 4.35 DSC curve of DMPC vesicles of various sizes (511, Sample, DMPC vesicle suspension liquid sample mass, lipid concentration 2 mmol L heating rate, 0.75"C min atmosphere, Nj sample vessel, tantalum-niobium alloy, 1.2 ml, scaled type reference, buffer solution vesicle size I,. 300-1000 nm, muti-layers II, average 200 nm, 3-4 layers HI, 40 nm, single layer...

Ether glycerophospholipid species with a saturated ether linkage have been reported as a low molecular mass lipidic modulator of glucocorticoid receptors (Schulman etal., 1992). The occurrence of l-(9-alkyl-T-enyl-2-lyso- n-glycero-... 

In special cases (as in colloidal solutions) some particles can be considered as essential and other particles as irrelevant , but in most cases the essential space will itself consist of collective degrees of freedom. A reaction coordinate for a chemical reaction is an example where not a particle, but some function of the distance between atoms is considered. In a simulation of the permeability of a lipid bilayer membrane for water [132] the reaction coordinate was taken as the distance, in the direction perpendicular to the bilayer, between the center of mass of a water molecule and the center of mass of the rest of the system. In proteins (see below) a few collective degrees of freedom involving all atoms of the molecule, describe almost all the... 

Murphy, R.C., Mass Spectrometry of Lipids, Plenum Press, New York, 1993. 

Figure 13 Center-of-mass mean-square displacements computed from MD simulations at 323 K. (a) DPPC motion in the plane of a lipid bilayer averaged over 10 ps (b) DPPC motion in the plane of a lipid bilayer averaged over 100 ps (c) comparison of the DPPC m-plane mean-square displacement to linear and power law functions of time (d) comparison of the center-of-mass mean-square displacement from an MD simulation of liquid tetradecane to a linear function of time.

Analysis of neutron data in terms of models that include lipid center-of-mass diffusion in a cylinder has led to estimates of the amplitudes of the lateral and out-of-plane motion and their corresponding diffusion constants. It is important to keep in mind that these diffusion constants are not derived from a Brownian dynamics model and are therefore not comparable to diffusion constants computed from simulations via the Einstein relation. Our comparison in the previous section of the Lorentzian line widths from simulation and neutron data has provided a direct, model-independent assessment of the integrity of the time scales of the dynamic processes predicted by the simulation. We estimate the amplimdes within the cylindrical diffusion model, i.e., the length (twice the out-of-plane amplitude) L and the radius (in-plane amplitude) R of the cylinder, respectively, as follows ... 

Murphy, R. C. Mass Spectrometry of Lipids. New York Plenum Press, 1993. Shibamoto, T., Ed. Lipid Chromatographic Analysis. New York Marcel Dekker, 1993. 

The classical PTPs can be subdivided into receptorlike PTPs and nonreceptor, cytosolic PTPs. The second category of PTPs are broadly defined as dual specificity phosphatases (DSPs), which dephosphorylate pSer/ pThr as well as pTyr. MAP kinase phosphatases (MKPs) ( MAP kinase cascades) and PTEN are examples of DSP family members. Remarkably, PTEN also has lipid phosphatase activity that is specific for phosphatidylinositol-3,4,5-trisphosphate generated in response to the actions of PI3K. Finally, the class of low molecular mass (LM-) PTPs and that of CDC25 PTPs accomplish the cells repertoire of PTPs (Fig. 3). 

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