Anti-adhesives

Silicone fluids containing Si—H groups are also used for paper treatment. The paper is immersed in a solution or dilute emulsion of the polymer containing either a zinc salt or organo-tin compound. The paper is then air-dried and heated for two minutes at 80°C to cure the resin. The treated paper has a measure of water repellency and in addition some anti-adhesive properties. 

Following with bacterial infections and anti-adhesion strategies,86 88 NMR based structural studies have been conducted on O-polysaccharide chains in these past few years,38 40,42,43 in order to elucidate the molecular basis and the role of the lipopolysaccharides in these pathologies. 

Dendritic and Hyperbranched Glycoconjugates as Biomedical Anti-Adhesion Agents... 

This chapter will provide an overview of the research on anti-adhesion agents. Particular attention will be devoted to the anti-adherence agents derived from or foimd naturally in foods. In addition, the pathogen infection process, the architecture of host epithelial cell surfaces, and the chemistry and mechanisms involved in bacterial interactions with host cell surfaces will also be reviewed. 

There are some pofenfial limifafions of anti-adhesive strategies that must also be recognized. Pathogenic bacteria often encode genes for more than one type of adhesin, and, via a process knovm as phase variation (Flenderson et al., 1999), express adhesins on either a random or perhaps "as-needed" basis. Therefore, a cocktail of different anti-adhesive agents... 

FIGURE 2.2 Schematic illustration of adherence (A) and anti-adhesive agents probiotics (B), adhesin analogs (C), and receptor analogs (D). 

Many bacterial adhesins and host receptors have been identified and studied in great depth, as described in Section VII. Therefore, with every new adhesin or receptor discovered, a new opportunity arises to develop an anti-adherence mechanism that may inhibit or block the adhesin-receptor interaction, which is the ultimate aim of anfi-adhesion therapy (Kahane and Ofek, 1996 Moricouf et ah, 1990 Ofek and Doyle, 1994). In actual practice, there are several t) es of anfi-adhesive mechanisms including adhesin-based vaccines, innafe hosf-derived anti-adhesives, probiotics, adhesin analogs, and receptor analogs. 

TABLE 2.3 Synthetic and naturally occurring anti-adhesive receptor analogs... 

In addition to reducing urinary and stomach infections, cranberry juice has also been shovm to have anti-adhesive activity against oral bacteria, such as S. mutans (Guo et al, 1998 Weiss et al, 2002). In the latter study, the ability of saliva-coated S. mutans to adhere to saliva- or glucan-coated hydroxyapatite in the presence of 25% cranberry juice was greatly reduced by 40-85% as compared to the control, indicating that cranberry... 

Einally, another group of oligosaccharides that have attracted attention for their potential anti-adhesive activity are the mannooligosacchar-ides (MOS). The MOS can be extracted from natural sources, produced... 

Research aimed at imderstanding bacterial pathogenesis has established the importance of bacterial adherence in disease. This research has led to the identification of a number of both bacterial adhesins and potential host cell receptors. By imderstanding the detailed interactions between a bacterial adhesin and host receptor, it is possible to develop new mechanisms to prevent bacterial adhesion, thereby averting disease. Many promising anti-adhesion mechanisms have been developed and studied, but much more work is needed, both in vitro and in vivo, to establish the feasibility of these mechanisms. 

Kelly, C. G., and Younson, J. S. (2000). Anti-adhesive strategies in the prevention of infectious disease at mucosal surfaces. Expert. Opin. Investig. Drugs 9,1711-1712. 

Ofek, I., Hasty, D. L., and Sharon, N. (2003b). Anti-adhesion therapy of bacterial disease Prospects and problems. FEMS Immunol. Med. Microbiol. 38,181-191. 

Rosenberg, M., Greenstein, R. B.-N., Barki, M., and Goldberg, S. (1996). Hydrophobic interactions as a basis for interfering with microbial adhesion. In "Toward Anti-adhesion Therapy for Microbial Disease." (1. Kahane and 1. Ofek, eds), pp. 241-248. Plenum Press, New York, NY. 

Sharon, N., and Ofek, I. (2000). Safe as mother s milk Carbohydrates as future anti-adhesion drugs for bacterial diseases. Glycocon. J. 17, 659-664. 

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