Association colloids toxicity

Lipid-associated formulations of amphotericin B, liposomal amphotericin B (AmBisome) and amphotericin B lipid complex (Abelcet) have been approved for use in proven cases of candidiasis however, patients with invasive candidiasis have also been treated successfully with amphotericin B colloid dispersion (Amphotec or Amphocil). The lipid-associated formulations are less toxic but as effective as amphotericin B deoxycholate. 

Measurements of the total concentration of microelements in environmental samples provide little information on their bioavailability. In water, most studies of the susceptibility of fish to heavy metal poisoning have shown that the free hydrated metals ions are the most toxic [118-120]. Ions that are strongly complexed or associated with colloidal particles are usually considered to be less toxic. 

The association of pollutants such as trace metals, nutrients, and toxic organic molecules to colloids is intimately connected to the health of natural waters. Colloids, with their large specific surface area, play a dominant role in the transportation and eventual deposition of these pollutants. Of particular interest is the size speciation data. It is important to know not only the total amount of pollutant present but also where it is distributed. It has been inherently difficult to study pollutant-colloid interactions because of the lack of methods for particle size determination and fractionation as well as the low concentrations of pollutants present in many systems. This entry outlines a new approach using field-flow fractionation (FFF). 

In wetlands, diffusive flux of toxic organics associated with colloidal organic matter may also be important. The sediment serves as a reservoir of dissolved organic carbon. Diffusion of toxic organics absorbed to organic carbon compounds into and out of the sediment bed may be an important transport process in highly organic soils. 

Currently, toxic effects of AmB have been largely ameliorated with the advent of lipid formulations, in these formulations, deoxycholate has been replaced by other Upids that mask AmB from susceptible tissues, thus reducing toxicity and facilitating its preferential uptake by reticuloendothelial cells. Thus, this drug delivery results in increasing efficacy and reduced toxicity. Three Upid-associated formulations of amphotericin are commercially available Uposomal amphotericin B (AmBisome), amphotericin B lipid complex (Abelcet), and amphotericin B colloidal dispersimi (Amphocil). These compoimds have been considered between the most striking advances in Leishmania therapy [52],... 

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