Phospholipid coat

All enveloped human vimses acquire their phospholipid coating by budding through cellular membranes. The maturation and release of enveloped influenza particles is illustrated in Fig. 3.8. The capsid protein subunits are transported flom the ribosomes to the nucleus, where they combine with new viral RNA molecules and are assembled into the helical capsids. The haemagglutinin and neuraminidase proteins that project fiom the envelope of the normal particles migrate to the cytoplasmic membrane where they displace the normal cell membrane proteins. The assembled nucleocapsids finally pass out from the nucleus, and as they impinge on the altered cytoplasmic membrane they cause it to bulge and bud off completed enveloped particles flxm the cell. Vims particles are released in this way over a period of hours before the cell eventually dies. 

Rasiel, A. et al., Phospholipid Coated Poly(Lactic Acid) Microspheres for the Delivery of LHRH Analogues, Polymers for Advanced Technologies. 13, 127, 2002. 

Noun + participle time-consuming calculation, phospholipid-coated capillaries... 

Fluorocarbon-filled, phospholipid-coated microbubbles Assessment of response to angiogenesis inhibitor therapy Ultrasound contrast agent... 

Intravenously injected, fluorocarbon-filled, phospholipid-coated microbubbles by themselves have little or no therapeutic value unless they are made acoustically... 

Another method employed to minimize fouling is the use of phospholipid coating designed to mimic the normal mammalian cell membrane. The best studied of these compounds has been phosphorylcholine (PC). For example, Goreish et al. applied PC to polyethylene terephthalate substrate and found that PC decreased the number of inflammatory cells that bound to the substrate.79 More important, they also implanted PC-coated substrates intramuscularly in rabbits and found that at week 13, the encapsulation tissue as a result of the foreign body reaction was much thinner in the PC-treated tissue samples. 

For possible consequences of drug-membrane interactions on conformation and/or orientation, see also Chapter 5. The examples discussed provide support for the assumption that the active conformation can be induced by the lipid environment. In other cases, however, inactivity may be related to such changes. Using NOE-NMR, changes in conformation have also been shown for verapamil in the presence of lipid-mimetic solvents such as acetonitrile [140] and for the binding of verapamil and verapamil analogs to amphiphilic surfaces (phospholipid-coated poly-styrene-divinylbenzene beads) [141]. 

To predict in vivo permeabilities, the parallel artificial membrane permeability assay (PAMPA) was introduced in 1998. Since then, it has gathered considerable interest in the pharmaceutical industry [41-47]. This method uses a phospholipid-coated filter separating two aqueous compartments to mimic the passive transport of small molecules. It readily provides information about passive-transport perme-... 

Haynes, D.H. Phospholipid-Coated Microcrystals Injectable Eormulations of Water-Insoluble Drugs. US Patents 5,091,187 and 5,091,188, Eeb 25, 1992, assigned to inventor Miami, EL. 

De Cuyper M, Muller P, Lueken H, Hodenius M (2003) Synthesis of magnetic Fe O particles covered with a modifiable phospholipid coat. J Phys Condens Matter 15 S1425-S1436... 

Another group having done extensive studies on the influence of preparation procedure on liposphere characteristics is Cortesi et al. [36], Strictly speaking, they were not investigating particles as described by Domb, who states in the patent that phospholipids may be replaced only in part with surfactants such as Tween, Span, and PEG surfactants. Steroids cannot function alone but may be incorporated, and amphiphiles can be added to the phospholipid coating to alter the surface charge [1],... 

Domb claims in his patent that the release rate of incorporated substances is controlled by both the phospholipid coating and the carrier [1], The first peptide-loaded... 

Stabilization of BLMs at the surface of electrodes has been reported by a number of groups [28-30]. For example, the tip of a Teflon-coated platinum microelectrode was cut in situ with a scalpel while immersed in a lipid solution (lipid in a hydrocarbon solvent). Upon immersion of the wire into an aqueous solution of 0.1 M KCl, the phospholipid coating adhering to the metal surface spontaneously thinned to form a BLM directly adjacent to the electrode surface... 

The SERRS of P-450 (rat Ever) adsorbed onto a phosphatidyl-choline/silver colloid (citrate-reduced) substrate leads to a low to high spin-state conversion. This spin-state marker band shift is ascribed to a strong interaction of P-450 with the phospholipid coating [17]. 

The other predominant factor affecting the survival of the bubbles is the coating surrounding the bubble. Most of our work has centered on phospholipid-coated microbubbles. We have seen that bubbles tend to be more stable when prepared using saturated lipids rather than unsaturated lipids and that longer chain lipids may allow preparation of somewhat more stable microbubbles. This is consistent with experimental work... 

The outer shell or film coating the microbubble is a layer of phospholipid coating an inner gaseous core of perfluorocarbon gas, perfluoropropane, in the case of Definity microbubbles (Lantheus Medical Imaging, N. Billerica, Mass.) which was... 

Soletti L, Nieponice A, Hong Y, Ye SH, Stankus JJ, Wagner WR, et al. In vivo performance of a phospholipid-coated bioerodable elastomeric graft for small-diameter vascular applications. J Biomed Mater Res A 2011 96(2) 436-48. 

No.2, Feb.2002, p. 127-36 PHOSPHOLIPID COATED POLYLACTIC ACID MICROSPHERES FOR THE DELIVERY OF LHRH ANALOGUES... 

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