La Alianza Cacao Per? y la cadena productiva del cacao fino de aroma

El Per?, por sus condiciones pol?ticas y econ?micas; su clima y biodiversidad para el cultivo de una amplia variedad de tipos de cacao; el reconocimiento por parte de la ICCO como pa?s productor de cacao fino de aroma (CFdA), y una cultura cacaotera a?n en crecimiento, es atractivo para empresas de la industria del cacao interesadas en pa?ses que ofrezcan condiciones para asegurar responsabilidad social y ambiental en sus operaciones. Desde el a?o 2012, la USAID promueve fondos mediante alianzas para el desarrollo global (GDA) en pa?ses que han mostrado mejora y crecimiento en los ?ltimos a?os, entre ellos el Per?. Mediante las GDA se busca la participaci?n p?blico-privada en iniciativas y proyectos de negocios que al mismo tiempo cumplan los objetivos de la USAID. En este contexto, surgi? el proyecto de la Alianza Cacao Per? (ACP), cuyo objetivo es posicionar al pa?s como uno de los l?deres mundiales de la producci?n del CFdA y mejorar las condiciones de vida del productor a trav?s de un modelo de negocio sostenible y alternativo al predominante en el pa?s. El objetivo de este libro es presentar un estudio del modelo propuesto por la ACP y compararlo con la cadena tradicional de producci?n del cacao. La investigaci?n se plantea un conjunto de preguntas como: ?cu?les son las fortalezas y las debilidades de ambos modelos?, ?qu? ventajas ofrece el modelo de negocio basado en la cadena productiva del CFdA de la ACP frente al modelo de la cadena productiva del cacao tradicional? y ?cu?les son los factores cr?ticos de ?xito para el sostenimiento del modelo de negocio basado en la cadena productiva del CFdA de la ACP

Distinction between signaling mechanisms in lipid rafts vs. caveolae

The relative importance of lipid rafts vs. specialized rafts termed caveolae to influence signal transduction is not known. Here we show that in cells lacking caveolae, the dually acylated protein, endothelial nitric oxide synthase (eNOS), localizes to cholesterol-rich lipid raft domains of the plasma membrane. In these cells, expression of caveolin-1 (cav-1) stimulates caveolae biogenesis, promotes the interaction of cav-1 with eNOS, and the inhibition of NO release from cells. Interestingly, in cells where cav-1 does not drive caveolae assembly, despite equal levels of cav-1 and eNOS and localization of both proteins to raft domains of the plasmalemma, the physical interaction of eNOS with cav-1 is dramatically less resulting in less inhibition of NO release. Thus, cav-1 concentrated in caveolae, not in rafts, is in closer proximity to eNOS and is necessary for negative regulation of eNOS function, thereby providing the first clear example of spatial regulation of signaling in this organelle that is distinct from raft domains

Functional interaction of endothelial nitric oxide synthase with a voltage-dependent anion channel

Endothelium-derived nitric oxide (NO) is an important regulator of vascular function. NO is produced by endothelial NO synthase (eNOS) whose function is modulated, in part, by specific protein interactions. By coimmunoprecipitation experiments followed by MS analyses, we identified a human voltage-dependent anion/cation channel or porin as a binding partner of eNOS. The interaction between porin and eNOS was demonstrated by coimmunoprecipitation studies in nontransfected human endothelial cells and Cos-7 cells transiently transfected with eNOS and porin cDNAs. In vitro binding studies with glutathione S-transferase–porin indicated that porin binds directly to eNOS and that this interaction augmented eNOS activity. The calcium ionophore, A23187, and bradykinin, which are known to activate eNOS, markedly increased porin–eNOS interaction, suggesting a potential role of intracellular Ca(2+) in mediating this interaction. Theses results indicate that the interaction between a voltage-dependent membrane channel and eNOS may be important for regulating eNOS activity

Host cell factor requirement for hepatitis C virus enzyme maturation

The cellular chaperone, HSP90, is identified here as an essential factor for the activity of NS2/3 protease of hepatitis C virus. The cleavage activity of NS2/3 protease synthesized in reticulocyte lysate is ATP-dependent, as evidenced by ATP depletion experiments and inhibition with nonhydrolyzable ATP analogs. Geldanamycin and radicicol, ATP-competitive inhibitors of the chaperone HSP90, also inhibit the cleavage of in vitro-synthesized NS2/3. Furthermore, these HSP90 inhibitors prevent NS2/3 cleavage when the protease is expressed in mammalian cells. The physical association of NS2/3 with HSP90 is demonstrated by immunoprecipitation. Thus, by way of a chaperone/folding activity, an HSP90-containing complex is required for maturation of the polyprotein that encodes the enzymes essential for hepatitis C virus replication

Endothelial nitric oxide synthase activation is critical for vascular leakage during acute inflammation in vivo

The role of endothelium-derived nitric oxide (NO) in acute inflammation is not known. Here, we examine acute inflammation in congenic endothelial NO synthase-deficient (eNOS(-/-)) mice. Intraplantar injection of carrageenan induces a biphasic inflammatory response. The early phase (0-6 h) is largely eliminated, and the secondary phase (24-96 h) is markedly reduced in eNOS(-/-) but not WT mice. Inhibition of phosphatidylinositol 3-kinase or hsp90, pathways upstream of eNOS activation, also reduces carrageenan-stimulated edema formation. To separate the ability of eNOS to regulate leukocyte trafficking vs. vascular permeability, zymosan-stimulated leukocyte infiltration and protein extravasation were assessed in WT and eNOS(-/-) mice. Zymosan increases inflammatory cell extravasation to the same extent in WT and eNOS(-/-) mice, whereas the extravasation of plasma protein is lower in eNOS(-/-) mice. Inhibition of phosphatidylinositol 3-kinase and hsp90 also blocks protein leakage, but not leukocyte influx. These data collectively support the critical role for eNOS in regulating the magnitude of the acute inflammatory response and show that eNOS is critical for regulating microcirculatory endothelial barrier function in vivo

A connecting hinge represses the activity of endothelial nitric oxide synthase

In mammals, endothelial nitric oxide synthase (eNOS) has the weakest activity, being one-tenth and one-sixth as active as the inducible NOS (iNOS) and the neuronal NOS (nNOS), respectively. The basis for this weak activity is unclear. We hypothesized that a hinge element that connects the FMN module in the reductase domain but is shorter and of unique composition in eNOS may be involved. To test this hypothesis, we generated an eNOS chimera that contained the nNOS hinge and two mutants that either eliminated (P728IeNOS) or incorporated (I958PnNOS) a proline residue unique to the eNOS hinge. Incorporating the nNOS hinge into eNOS increased NO synthesis activity 4-fold, to an activity two-thirds that of nNOS. It also decreased uncoupled NADPH oxidation, increased the apparent KmO2 for NO synthesis, and caused a faster heme reduction. Eliminating the hinge proline had similar, but lesser, effects. Our findings reveal that the hinge is an important regulator and show that differences in its composition restrict the activity of eNOS relative to other NOS enzymes