Brain pathogens

Lipid raft A membrane area enriched in cholesterol and sphingolipids, also referred to as membrane microdomains or sphingolipid microdomains. Lipid rafts are involved in signal transduction functions. Most brain pathogens use lipid raft as portal of entry in brain cells. 

Chloroform-methanol extracts of Borrelia burgdorferi were used for the identification of lipids and other related components that could help in the diagnosis of Lyme disease [58]. The provitamin D fraction of skin lipids of rats was purified by PTLC and further analyzed by UV, HPLC, GLC, and GC-MS. MS results indicated that this fraction contained a small amount of cholesterol, lathosterol, and two other unknown sterols in addition to 7-dehydrocholesterol [12]. Two fluorescent lipids extracted from bovine brain white matter were isolated by two-step PTLC using silica gel G plates [59]. PTLC has been used for the separation of sterols, free fatty acids, triacylglycerols, and sterol esters in lipids extracted from the pathogenic fungus Fusarium culmorum [60]. 

Once through the blood-brain barrier, pathogens thrive and replicate due to limited host defenses in the CNS. Figure 67-1 depicts the pathophysiologic changes associated... 

Walkley, S. U. Pathogenic cascades in brain dysfunction. In F. M. Platt and S. U. Walkley (eds), Lysosomal Disorders of the Brain. New York Oxford University Press, 2004, pp. 290-324. 

Infection by PrPSc is a more challenging—and obscure—process. Pathogens in mammals not only have to spread within an infected organism but also they must spread from one organism to another. The route of transmission followed by PrPSc is more complicated than that of fungal prions and places more requirements on this system. Tissues other than brain are also involved (Aguzzi, 2003 Seeger et al., 2005). 

Chloramphenicol [20 CAP D-(—)-ft reo-l-(p-nitrophenyl)-2-(dichloroacetamido)-l,3-propanediol] is an important antibiotic due to its broad activity against a number of clinically relevant microbial pathogens and its ability to penetrate easily the blood-brain barrier. Besides human application, CAP became widely and routinely used in veterinary practice and is used in Europe in most animal productions including fish128. 

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