Enseñando a una avestruz a trepar un árbol

Las competencias son características personales, que se evidencian a partir de comportamientos, conocimientos, habilidades y actitudes y generan un desempeño exitoso, en un cargo o labor determinada. A menudo, las organizaciones seleccionan su personal de acuerdo a las aptitudes, necesarias para desempeñar algunas funciones específicas. Sin embargo, ser apto para un cargo, va más allá, ello incluye el desarrollo del saber, que está dado por los conocimientos, las habilidades que definen el saber hacer y las competencias que determinan el saber, entendiendo lo que se hace. Frente a un reto como este, los jefes de área deben estar en la capacidad de diagnosticar lo que está ocurriendo, determinar sus causas, y adoptar planes de acción para lograr los objetivos. El propósito de este ensayo, es a través del desarrollo de tres capítulos, resaltar la importancia de definir perfiles por competencias, para todos los cargos a proveer en las organizaciones, apoyada en el estudio y análisis de expertos en el tema de gestión por competencias

Intercambio precolombino entre el Pacífico Norte y la región de San Ramón del 600 al 1550 D.C.

La presente investigación busca aportar a la comprensión y a la caracterización del intercambio entre el Pacífico Norte y la zona de San Ramón, por lo que se plantea si el intercambio de cerámica policroma entre estas dos regiones fue a través de un modelo de “emisario de élite”, de un modelo de distribución no centralizada, o responde a un modelo distinto. Para llevar a cabo la investigación se utilizaron las colecciones cerámicas recuperadas durante las investigaciones realizadas en la zona de San Ramón en el marco del proyecto “Cambio social precolombino en San Ramón de Alajuela y sus alrededores”, se realizó un análisis cerámico, mapas de concentración de la cerámica policroma en el sitio Barranca, y se determinaron las frecuencias de cerámica policroma en los sitios de la zona de San Ramón, datos que fueron utilizados en la elaboración de un gráfico de regresión para determinar la relación entre la desembocadura del río Barranca y el porcentaje de cerámica policroma en los sitios. Como resultados de la investigación se pudo determinar que para la zona de San Ramón se cumplen algunos de los postulados del modelo de distribución no centralizada, sin embargo otros de los datos que se obtuvieron deben tomar en cuenta el desarrollo de la producción en masa que se estaba dando en centros manufactureros en el área norte de la Gran Nicoya, como es el caso de Granada, donde se estaba produciendo el tipo Papagayo Policromo, que es el que presenta mayores frecuencias en la zona de San Ramón. A partir de la presente investigación surgieron una serie de interrogantes que deben ser contestadas a partir de nuevas investigaciones en la región.UCR::Vicerrectoría de Investigación::Sistema de Estudios de Posgrado::Ciencias Sociales::Maestría Académica en Antropologí

Isolation, characterization and molecular cloning of AnMIP, a new α-type phospholipase A2 myotoxin inhibitor from the plasma of the snake Atropoides nummifer (Viperidae: Crotalinae)

A new phospholipase A2 (PLA2)-inhibitory protein was isolated from the plasma of Atropoides nummifer, a crotaline snake from Central America. This inhibitor was named AnMIP, given its ability to neutralize the activity of basic PLA2 myotoxins of its own and related venoms. The cDNA of AnMIP was cloned and sequenced, showing that it belongs to the α group of phospholipase A2 inhibitors (PLIs). AnMIP appears as a homotrimer in the native state, held together by non-covalent forces, with a subunit molecular mass of 22,247–22,301 and an isoelectric point of 4.1–4.7. This trimeric structure is the first observed in a PLIα from American crotaline snakes, previously reported only in Asian species. Sequencing, mass spectrometry, and analytical isoelectrofocusing indicated the existence of isoforms, as reported for other PLIαs isolated from snake plasma. The inhibitory profile of AnMIP showed specificity towards group II PLA2s, either belonging to the catalytically-active (D49) or -inactive (K49) subtypes, exemplified in this study by Bothrops asper myotoxin I and A. nummifer myotoxin II, respectively. By phylogenetic analysis it was shown that AnMIP is closely related to CgMIP-II, previously isolated from the plasma of Cerrophidion godmani, showing 93% amino acid sequence identity.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)UCR::Vicerrectoría de Docencia::Salud::Facultad de MicrobiologíaUCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicin

Antivenomics of Atropoides mexicanus and Atropoides picadoi snake venoms: Relationship to the neutralization of toxic and enzymatic activities

Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an ‘antivenomics’ approach, the ability of a polyspecific (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are not included in the immunization mixture. In addition, the neutralization of lethal, hemorrhagic, myotoxic, coagulant, proteinase and phospholipase A2 (PLA2) activities of these venoms by the antivenom was assessed. The antivenom was highly-effective in immunodepleting many venom components, particularly high molecular mass P-III metalloproteinases (SVMPs), L-amino acid oxidases, and some serine proteinases and P-I SVMPs. In contrast, PLA2s, certain serine proteinases and P-I SVMPs, and a C type lectin-like protein were only partially immunodepleted, and two PLA2 molecules were not depleted at all. The antivenom was able to neutralize all toxic and enzymatic activities tested, although neutralization of lethality by A. nummifer venom was achieved when a challenge dose of 3 LD50s of venom was used, but was iffective when 4 LD50s were used. These results, and previously obtained evidence on the immunoreactivity of this antivenom towards homologous and heterologous venoms, revealed the low immunogenicity of a number of venom components (PLA2s, CRISPs, P-I SVMPs, and some serine proteinases), underscoring the need to search for innovative immunization protocols to improve the immune response to these antigens

Analizar la manera en que las acciones de los sindicatos influyen sobre la cultura organizacional de la empresa COCA-COLA

Gráficas, encuestaLa compañía Coca cola se fundó en 1891 formada por el también farmacéutico Asa G. Candler, su hermano John S. Candler y Frank Robinson. Dos años después registraron la marca en la Oficina de Registro de la Propiedad Industrial de los Estados Unidos. Coca Cola, tiene presencia en 10 países en América Latina esta compañía comprende que cada población es diferente, y que cada una tiene sus propias necesidades y hábitos. Es por eso que esta compañía se ha comprometido en satisfacer a sus consumidores, además de estar comprometidos y de desarrollar de manera sostenible cada comunidad donde operan. A lo largo de los años esta compañía ha ido transformando sus modelos de operación el cual les permitirá tener ventaja competitiva para generar una mayor cadena de valor, es ahí donde sus empleados juegan un papel fundamental porque son ellos los responsables de fortalecer las relaciones humanas y de ser capaces de generar cambios. La cultura organizacional de una empresa permite crear un conjunto de ideas, prácticas y valores que tienen en común los diversos agentes de una misma empresa. Esto involucra aspectos que engloban la ética, las creencias, la experiencia y la psicología del grupo. Además, establece las relaciones tanto de directivos como de empleados entre sí. Y por supuesto, la relación entre estos y los elementos externos como proveedores, usuarios y clientes.The Coca-Cola Company was founded in 1891 by fellow pharmacist Asa G. Candler, his brother John S. Candler, and Frank Robinson. Two years later they registered the trademark in the Industrial Property Registry Office of the United States. Coca Cola has a presence in 10 countries in Latin America, this company understands that each population is different, and that each one has its own needs and habits. That is why this company is committed to satisfying its consumers, in addition to being committed to and sustainably developing each community where they operate. Over the years, this company has been transforming its operating models which will allow them to have a competitive advantage to generate a greater value chain, that is where its employees play a fundamental role because they are responsible for strengthening human relations and to be able to generate change. The organizational culture of a company allows the creation of a set of ideas, practices and values that the various agents of the same company have in common. This involves aspects that encompass the ethics, beliefs, experience and psychology of the group. In addition, it establishes the relationships of both managers and employees with each other. And of course, the relationship between these and external elements such as suppliers, users and customers

Integrated “omics” profiling indicates that miRNAs are modulators of the ontogenetic venom composition shift in the Central American rattlesnake, Crotalus simus simus

Background Understanding the processes that drive the evolution of snake venom is a topic of great research interest in molecular and evolutionary toxinology. Recent studies suggest that ontogenetic changes in venom composition are genetically controlled rather than environmentally induced. However, the molecular mechanisms underlying these changes remain elusive. Here we have explored the basis and level of regulation of the ontogenetic shift in the venom composition of the Central American rattlesnake, Crotalus s. simus using a combined proteomics and transcriptomics approach. Results Proteomic analysis showed that the ontogenetic shift in the venom composition of C. s. simus is essentially characterized by a gradual reduction in the expression of serine proteinases and PLA2 molecules, particularly crotoxin, a β-neurotoxic heterodimeric PLA2, concominantly with an increment of PI and PIII metalloproteinases at age 9–18 months. Comparison of the transcriptional activity of the venom glands of neonate and adult C. s. simus specimens indicated that their transcriptomes exhibit indistinguisable toxin family profiles, suggesting that the elusive mechanism by which shared transcriptomes generate divergent venom phenotypes may operate post-transcriptionally. Specifically, miRNAs with frequency count of 1000 or greater exhibited an uneven distribution between the newborn and adult datasets. Of note, 590 copies of a miRNA targeting crotoxin B-subunit was exclusively found in the transcriptome of the adult snake, whereas 1185 copies of a miRNA complementary to a PIII-SVMP mRNA was uniquely present in the newborn dataset. These results support the view that age-dependent changes in the concentration of miRNA modulating the transition from a crotoxin-rich to a SVMP-rich venom from birth through adulhood can potentially explain what is observed in the proteomic analysis of the ontogenetic changes in the venom composition of C. s. simus. Conclusions Existing snake venom toxins are the result of early recruitment events in the Toxicofera clade of reptiles by which ordinary genes were duplicated, and the new genes selectively expressed in the venom gland and amplified to multigene families with extensive neofunctionalization throughout the approximately 112–125 million years of ophidian evolution. Our findings support the view that understanding the phenotypic diversity of snake venoms requires a deep knowledge of the mechanisms regulating the transcriptional and translational activity of the venom gland. Our results suggest a functional role for miRNAs. The impact of specific miRNAs in the modulation of venom composition, and the integration of the mechanisms responsible for the generation of these miRNAs in the evolutionary landscape of the snake's venom gland, are further challenges for future research.Ministerio de Economía y Competitividad/[BFU2010-17373]//EspañaGeneralitat Valenciana/[PROMETEO/2010/005]//EspañaUniversidad de Costa Rica/[741-B2-093]/UCR/Costa Rica/2009CR0021/CRUSA-CSIC/EspáñaPrograma Iberoamericano de Ciencia y Tecnología para el Desarrollo/206AC0281/CYTED/EspañaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP

Snake venomics of the South and Central American Bushmasters. Comparison of the toxin composition of Lachesis muta gathered from proteomic versus transcriptomic analysis

We report the proteomic characterization of the venoms of two closely related pit vipers of the genus Lachesis, L. muta (South American Bushmaster) and L. stenophrys (Central American Bushmaster), and compare the toxin repertoire of the former revealed through a proteomic versus a transcriptomic approach. The protein composition of the venoms of Lachesis muta and L. stenophrys were analyzed by RP-HPLC, N-terminal sequencing, MALDI-TOF peptide mass fingerprinting and CID-MS/MS. Around 30–40 proteins of molecular masses in the range of 13–110 kDa and belonging, respectively, to only 8 and 7 toxin families were identified in L. muta and L. stenophrys venoms. In addition, both venoms contained a large number of bradykinin-potentiating peptides (BPP) and a C-type natriuretic peptide (C-NP). BPPs and C-NP comprised around 15% of the total venom proteins. In both species, the most abundant proteins were Zn2+-metalloproteinases (32–38%) and serine proteinases (25–31%), followed by PLA2s (9–12%), galactose-specific C-type lectin (4–8%), l-amino acid oxidase (LAO, 3–5%), CRISP (1.8%; found in L. muta but not in L. stenophrys), and NGF (0.6%). On the other hand, only six L. muta venom-secreted proteins matched any of the previously reported 11 partial or full-length venom gland transcripts, and venom proteome and transcriptome depart in their relative abundances of different toxin families. As expected from their close phylogenetic relationship, the venoms of L. muta and L. stenophrys share (or contain highly similar) proteins, in particular BPPs, serine proteinases, a galactose-specific C-type lectin, and LAO. However, they dramatically depart in their respective PLA2 complement. Intraspecific quantitative and qualitative differences in the expression of PLA2 molecules were found when the venoms of five L. muta specimens (3 from Bolivia and 2 from Peru) and the venom of the same species purchased from Sigma were compared. These observations indicate that these class of toxins represents a rapidly-evolving gene family, and suggests that functional differences due to structural changes in PLA2s molecules among these snakes may have been a hallmark during speciation and adaptation of diverging snake populations to new ecological niches, or competition for resources in existing ones. Our data may contribute to a deeper understanding of the biology and ecology of these snakes, and may also serve as a starting point for studying structure–function correlations of individual toxins.Ministerio de Educación y Ciencia/[BFU2004-01432/BMC]//EspañaConsejo Superior de Investigaciones Científicas/[CSIC-UCR 2006CR0010]/CSIC-UCR/EspañaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP

Biochemistry and toxicology of toxins purified from the venom of the snake Bothrops asper

The isolation and study of individual snake venom components paves the way for a deeper understanding of the pathophysiology of envenomings – thus potentially contributing to improved therapeutic modalities in the clinical setting – and also opens possibilities for the discovery of novel toxins that might be useful as tools for dissecting cellular and molecular processes of biomedical importance. This review provides a summary of the different toxins that have been isolated and characterized from the venom of Bothrops asper, the snake species causing the majority of human envenomings in Central America. This venom contains proteins belonging to at least eight families: metalloproteinase, serine proteinase, C-type lectin-like, L-amino acid oxidase, disintegrin, DC-fragment, cystein-rich secretory protein, and phospholipase A2. Some 25 venom proteins within these families have been isolated and characterized. Their main biochemical properties and toxic actions are described, including, in some cases, their possible relationships to the pathologic effects induced by B. asper venom.Universidad de Costa Rica//UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicin

Differential susceptibility of C2C12 myoblasts and myotubes to group II phospholipase A2 myotoxins from crotalid snake venoms

Group II phospholipase A2 (PLA2) myotoxins isolated from Viperidae/Crotalidae snake venoms induce a rapid cytolytic effect upon diverse cell types in vitro. Previous studies suggested that this effect could be more pronounced on skeletal muscle myotubes than on other cell types, including undifferentiated myoblasts. This study utilized the murine skeletal muscle C2C12 cell line to investigate whether differentiated myotubes are more susceptible than myoblasts, and if this characteristic is specific for the group II myotoxic PLA2s. The release of lactic dehydrogenase was quantified as a measure of cytolysis, 3 h after cell exposure to different group II PLA2s purified from Bothrops asper, Atropoides nummifer, Cerrophidion godmani, and Bothriechis schlegelii venoms. In addition, susceptibility to lysis induced by synthetic melittin and group III PLA2 from bee (Apis mellifera) venom, as well as by anionic, cationic, and neutral detergents, was comparatively evaluated on the two cultures. Myotubes were significantly more susceptible to group II PLA2 myotoxins, but not to the other agents tested, under the same conditions. Moreover, the increased susceptibility of myotubes over myoblasts was also demonstrated with two cytolytic synthetic peptides, derived from the C-terminal region of Lys49 PLA2 myotoxins, that reproduce the action of their parent proteins. These results indicate that fusion and differentiation of myoblasts into myotubes induce changes that render these cells more susceptible to the toxic mechanism of group II PLA2 myotoxins, but not to general perturbations of membrane homeostasis. Such changes are likely to involve myotoxin acceptor site(s), which remain(s) to be identified.International Foundation for Science/[F/2766-2]/IFS/SueciaUniversidad de Costa Rica/[741-99-269]/UCR/Costa RicaUniversidad de Costa Rica/[741-A3-513]/UCR/Costa RicaConsejo Nacional para Investigaciones Científicas y Tecnológicas/[FV058-02]/CONICIT-FORINVES/Costa RicaNeTropica Sweden-Central America network/[]//SueciaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicin

Isolation of bothrasperin, a disintegrin with potent platelet aggregation inhibitory activity, from the venom of the snake Bothrops asper

The venom of Bothrops asper induces severe coagulation disturbances in accidentally envenomed humans. However, only few studies have been conducted to identify components that interact with the hemostatic system in this venom. In the present work, we fractionated B. asper venom in order to investigate the possible presence of inhibitors of platelet aggregation. Using a combination of gel filtration, anion-exchange chromatography, and reverse-phase high performance liquid chromatography, we isolated an acidic protein which shows a single chain composition, with a molecular mass of ~8 kDa, estimated by SDS-polyacrylamide gel electrophoresis. Its N-terminal sequence has high similarity to disintegrins isolated from different snake venoms, which are known to bind to cellular integrins such as the GPIIb/IIIa fibrinogen receptor on platelets. The purified protein exerted potent aggregation inhibitory activity on ADP-stimulated human platelets in vitro, with an estimated IC50 of 50 nM. This biological activity, together with the biochemical characteristics observed, demonstrate that the protein isolated from B. asper venom is a disintegrin, hereby named "bothrasperin". This is the first disintegrin isolated from Central American viperid snake species.El veneno de la serpiente Bothrops asper induce graves alteraciones de la coagulación en los humanos accidentalmente envenenados. Sin embargo, se han realizado pocos estudios para identificar los componentes del veneno que interactúan con el sistema hemostático. En el presente trabajo, fraccionamos el veneno de B. asper para investigar la posible presencia de inhibidores de la agregación plaquetaria. Empleando una combinación de técnicas cromatográficas (filtración en gel, intercambio aniónico y cromatografía líquida de alto desempeño en fase reversa), aislamos una proteína acídica de cadena simple, con una masa molecular de ~8 kDa, estimada mediante electroforesis en gel de poliacrilamida con SDS. Su secuencia de aminoácidos N-terminal muestra una alta similitud con la de disintegrinas aisladas de diferentes venenos de serpiente, las cuales se unen a integrinas celulares como el receptor de fibrinógeno GPIIb/IIIa de las plaquetas. La proteína purificada ejerce una potente acción inhibitoria sobre la agregación in vitro de plaquetas humanas estimuladas con ADP, con una IC 50 estimada en 50 nM. Esta actividad biológica, sumada a las características bioquímicas observadas, demuestran que la proteína aislada del veneno de B. asper es una disintegrina, a la cual denominamos "both-rasperina". Esta es la primera disintegrina aislada de una especie de vipéridos de Centroamérica