Coca in History and Political Economy

Book reviewed in this article:
Coca Prohibition in Peru: The Historical Debates . Joseph Gagliano.
The Coca Boom and Rural Social Change in Bolivia . Harry Sanabria.     

The role of hallucinogenic drugs and sensory stimuli in Peruvian ritual healing

On Peru's north coast, curanderos perform night-long curing ceremonies in which the mescaline-bearing cactus San Pedro is used. The concept of autonomic nervous system tuning is presented as the best explanation for the overall physiological effect of the ritual. An assessment of the possible therapeutic impact of this condition is provided. Organic response and symbolic message are seen to resonate in the purificatory connotations of the ritual.     

Antigen-decorated shell cross-linked nanoparticles: synthesis, characterization, and antibody interactions

Antigen-decorated shell cross-linked knedel-like nanoparticles (SCKs) were synthesized and studied as multivalent nanoscale surfaces from which antibody-binding units were presented in a manner that was designed to approach virus particle surfaces. The SCK nanostructures were fabricated with control over the number of antigenic groups, from mixed micellization of amphiphilic diblock copolymer building blocks that contained either an antigen (2,4-dinitrophenyl) or an ethylpropionate group at the hydrophilic alpha-chain terminus. Amphiphilic diblock copolymers were synthesized by atom transfer radical polymerization of tert-butyl acrylate and methyl acrylate sequentially from either a 2,4-dinitrophenyl-functionalized initiator or ethyl 2-bromopropionate, followed by selective removal of the tert-butyl groups to afford 2,4-dinitrophenyl-poly(acrylic acid)60-b-poly(methyl acrylate)60 (DNP-PAA(60)-b-PMA60) and poly(acrylic acid)70-b-poly(methyl acrylate) (PAA70-b-PMA70). Micelles were assembled via addition of water to THF solutions of the polymers in 0:1, 1:1, and 1:0 molar ratios of DNP-PAA60-b-PMA60 to PAA70-b-PMA70, followed by dialysis against water. The acrylic acid groups of the micelle coronas were partially cross-linked (nominally 50%) with 2,2'-(ethylenedioxy)bis(ethylamine), in the presence of 1-(3'-dimethylaminopropyl)-3-ethylcarbodiimide methiodide. Following extensive dialysis against water, the 0%, 50%, and 100% dinitrophenylated shell cross-linked nanoparticles (DNP-SCKs) were characterized with dynamic light scattering (DLS), transmission electron microscopy (TEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), infrared and UV-vis spectroscopies, and analytical ultracentrifugation (AU). The surface accessibility and bioavailability of the DNP units upon the DNP-SCKs were investigated by performing quenching titrations of fluorescein-labeled IgE antibody in solution and degranulation of IgE sensitized RBL-2H3 cells. The DNP antigens proved to be surface-available and able to form multivalent bonds with IgE antibodies, causing degranulation.     

An assessment of the effects of shell cross-linked nanoparticle size, core composition, and surface PEGylation on in vivo biodistribution

Amphiphilic core-shell nanoparticles have drawn considerable interest in biomedical applications. The precise control over their physicochemical parameters and the ability to attach various ligands within specific domains suggest shell cross-linked (SCK) nanoparticles may be used as multi-/polyvalent scaffolds for drug delivery. In this study, the biodistribution of four SCKs, differing in size, core composition, and surface PEGylation, was evaluated. To facilitate in-vivo tracking of the SCKs, the positron-emitting radionuclide copper-64 was used. By using biodistribution and microPET imaging approaches, we found that small diameter (18 nm) SCKs possessing a polystyrene core showed the most favorable biological behavior in terms of prolonged blood retention and low liver accumulation. The data demonstrated that both core composition, which influenced the SCK flexibility and shape adaptability, and hydrodynamic diameter of the nanoparticle play important roles in the respective biodistributions. Surface modification with poly(ethylene glycol) (PEG) had no noticeable effects on SCK behavior.     

Medical Pluralism in the Andes

Medical Pluralism in the Andes . Joan D. Koss-Chioino, Thomas Leatherman, and Christine Greenway. New York: Routledge, 2003. xix + 256 pp.     

Synthesis, characterization, and bioavailability of mannosylated shell cross-linked nanoparticles

Saccharide-functionalized shell cross-linked (SCK) polymer micelles designed as polyvalent nanoscaffolds for selective interactions with receptors on Gram negative bacteria were constructed from mixed micelles composed of poly(acrylic acid-b-methyl acrylate) and mannosylated poly(acrylic acid-b-methyl acrylate). The mannose unit was conjugated to the hydrophilic chain terminus of the amphiphilic diblock copolymer precursor, from which the SCK nanoparticles were derived, by the growth of the diblock copolymer from a mannoside functionalized atom transfer radical polymerization (ATRP) initiator. Mixed micelle formation between the amphiphilic diblock copolymer and mannosylated amphiphilic diblock copolymer was followed by condensation-based cross-linking between the acrylic acid residues present in the periphery of the polymer micelles to afford SCK nanoparticles. SCKs presenting variable numbers of mannose functionalities were prepared from mixed micelles of controlled stoichiometric ratios of mannosylated and nonmannosylated diblock copolymers. The polymer micelles and SCKs were characterized by dynamic light scattering (DLS), electrophoretic light scattering, atomic force microscopy (AFM), transmission electron microscopy (TEM), and analytical ultracentrifugation (AU). Surface availability and bioactivity of the mannose units were evaluated by interactions of the nanostructures with the model lectin Concanavalin A via DLS studies, with red blood cells (rabbit) via agglutination inhibition assays and with bacterial cells (E. coli) via TEM imaging.