45 research outputs found
Usporedba djelovanja korionskog gonadotropina konja (eCG) i estradiol cipionata primijenjenih 24 sata nakon prestanka kontrolirane primjene progesterona kao dijela protokola za sinkronizaciju estrusa i umjetno osjemenjivanje meksičkog Criollo goveda.
Two experiments were conducted to evaluate the effect of administering equine chorionic gonadotropin (eCG) in substitution of estradiol, 24 h after the removal of a progesterone intravaginal device, on estrus and ovulatory response, and pregnancy rates of Rodeo Criollo cows (exp. 1, n = 21) and heifers (exp. 2, n = 39) subjected to a synchronization protocol (estradiol + CIDR + PGF2α) with estrus-detected artificial insemination. All females were inseminated 12 h after detected estrus. In cows, estrus and ovulation response, and maximum pre-ovulatory follicle diameter were similar (P>0.05) between equine chorionic gonadotropin and estradiol groups. However, the time to estrus was shorter (P0.05) in ovulation rate. Both treatments resulted in low pregnancy rates, with a significantly lower (P0,05) u skupinama krava kod kojih je bio primijenjen korionski gonadrotropin ili estradiol. Međutim, u skupini kod koje je bio primijenjen estradiol vrijeme do estrusa je bilo kraće (P0,05) u stopi ovulacije. Oba su postupka dovela do niže stope gravidnosti, pri čemu je smanjenje kod junica kojima je bio primijenjen korionski gonadotropin konja bilo signifikantno (P<0,05). Zaključno, primjena korionskog gonadotropina konja, kao zamjene za estradiol nakon uklanjanja sredstva za otpuštanje progesterona, dovela je u sklopu protokola za otkrivanje estrusa i umjetno osjemenjivanje do povećanog grupiranja estrusa i ovulacije te posljedično veće stope gravidnosti u krava, ali ne i u junica
A FRET-based cGMP biosensor in Drosophila
CUTie2 is a FRET-based cGMP biosensor tested so far only in cells. To expand its use to multicellular organisms we generated two transgenic Drosophila melanogaster strains that express the biosensor in a tissue-dependent manner. CUTie2 expression and subcellular localization was verified by confocal microscopy. The performance of CUTie2 was analyzed on dissected larval brains by hyperspectral microscopy and flow cytometry. Both approaches confirmed its responsivity, and the latter showed a rapid and reversible change in the fluorescence of the FRET acceptor upon cGMP treatment. This validated reporter system may prove valuable for studying cGMP signaling at organismal level.Agencia Nacional de Investigación e InnovaciónDirección Nacional de Innovación, Ciencia y Tecnologí
Novel role for animal innate immune molecules: Enterotoxic activity of a snail egg MACPF-Toxin
Gastropod Molluscs rely exclusively on the innate immune system to protect from pathogens, defending their embryos through maternally transferred effectors. In this regard, Pomacea snail eggs, in addition to immune defenses, have evolved the perivitellin-2 or PV2 combining two immune proteins into a neurotoxin: a lectin and a pore-forming protein from the Membrane Attack Complex/Perforin (MACPF) family. This binary structure resembles AB-toxins, a group of toxins otherwise restricted to bacteria and plants. Many of these are enterotoxins, leading us to explore this activity in PV2. Enterotoxins found in bacteria and plants act mainly as pore-forming toxins and toxic lectins, respectively. In animals, although both pore-forming proteins and lectins are ubiquitous, no enterotoxins have been reported. Considering that Pomacea snail eggs ingestion induce morpho-physiological changes in the intestinal mucosa of rodents and is cytotoxic to intestinal cells in culture, we seek for the factor causing these effects and identified PmPV2 from Pomacea maculata eggs. We characterized the enterotoxic activity of PmPV2 through in vitro and in vivo assays. We determined that it withstands the gastrointestinal environment and resisted a wide pH range and enzymatic proteolysis. After binding to Caco-2 cells it promoted changes in surface morphology and an increase in membrane roughness. It was also cytotoxic to both epithelial and immune cells from the digestive system of mammals. It induced enterocyte death by a lytic mechanism and disrupted enterocyte monolayers in a dose-dependent manner. Further, after oral administration to mice PmPV2 attached to enterocytes and induced large dose-dependent morphological changes on their small intestine mucosa, reducing the absorptive surface. Additionally, PmPV2 was detected in the Peyer's patches where it activated lymphoid follicles and triggered apoptosis. We also provide evidence that the toxin can traverse the intestinal barrier and induce oral adaptive immunity with evidence of circulating antibody response. As a whole, these results indicate that PmPV2 is a true enterotoxin, a role that has never been reported to lectins or perforin in animals. This extends by convergent evolution the presence of plant- and bacteria-like enterotoxins to animals, thus expanding the diversity of functions of MACPF proteins in nature.Fil: Giglio, Matías Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Ituarte, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Ibañez, Esteban Andrés. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Dreon, Marcos Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Prieto, Eduardo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Fernández, Patricia Ester. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Heras, Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentin
Preparación de sustancias de referencia para laboratorios de producción pública de medicamentos
Las sustancias de referencia (SR, comúnmente llamadas estándares) son compuestos químicos que se emplean habitualmente en los sectores de desarrollo y control de calidad de laboratorios productores de medicamentos, como así también en centros de salud pública. Las mismas son indispensables para ensayos fisicoquímicos que involucren identificación y/o cuantificación del fármaco (entre ellos ensayos de valoración, uniformidad de contenido en unidades de dosificación, ensayo de disolución) o de otros compuestos relacionados con el fármaco (sustancias relacionadas) cuyos límites admitidos son bajos y están vinculados con toxicidad del tratamiento. Habitualmente se emplean SR provistas por la Food and Drug Administration (FDA) de Estados Unidos (USP-RS) o las certificadas en la Comunidad Económica Europea (PhE-RS). Debido a la diferencia cambiaria, tanto USP-RS como las PhE-RS se caracterizan por su alto costo y su adquisición implica una erogación significativa para las unidades públicas de producción de medicamentos y centros de salud pública. Algunas SR se encuentran disponibles desde la Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT), a un precio accesible. No obstante, las más costosas a nivel internacional, por ejemplo las de sustancias relacionadas, no se encuentran disponibles aún por esta vía.
Nuestro proyecto propone abordar la obtención de SR de algunos fármacos prioritarios definidos por unidades de producción pública de medicamentos de todo el país, focalizándonos en SR no disponibles en el listado de SR de ANMAT. Se prevé desarrollar los procedimientos de síntesis química, purificación, identificación y ensayos de control de calidad, que permitan obtener compuestos de referencia de máxima calidad y que cumplan requisitos impuestos por los órganos de control público. Las SR producidas se entregarán gratuitamente a unidades públicas de producción de medicamentos y centros de salud pública. Se reducirán de esta manera los costos de producción y control de medicamentos de centros de salud estatales y unidades productoras de medicamentos públicas. Este aporte redundará en un mejor aprovechamiento de los recursos (generalmente limitados) destinados a estas unidades.
Actualmente hemos avanzado en la obtención de SR de compuestos relacionados del enalapril (antihipertensivo) e ibuprofeno (analgésico, antiinflamatorio): dicetopiperacina del enalapril y 4-isobutilacetofenona, previéndose el inicio de su distribución gratuita a centros de salud pública y unidades de producción pública de medicamentos para fines de 2011. El proyecto se haya avalado por el Laboratorio Central de Salud Pública del Ministerio de Salud de la Provincia de Buenos Aires y por la Red de Laboratorios Públicos de Medicamentos para Producción, Investigación, Desarrollo y Servicios.Facultad de Ciencias Exacta
Cultural and leadership predictors of corporate social responsibility values of top management: A GLOBE study of 15 countries.
This paper examines cultural and leadership variables associated with corporate social responsibility values that managers apply to their decision-making. In this longitudinal study, we analyze data from 561 firms located in 15 countries on five continents to illustrate how the cultural dimensions of institutional collectivism and power distance predict social responsibility values on the part of top management team members. CEO visionary leadership and integrity were also uniquely predictive of such values. Journal of International Business Studies (2006) 37, 823–837. doi:10.1057/palgrave.jibs.8400230
The impact of societal cultural values and individual social beliefs on the perceived effectiveness of managerial influence strategies: a meso approach
This paper reports the findings of a 12-nation study designed to test empirically the relationships between societal cultural values, individual social beliefs, and the perceived effectiveness of different influence strategies. The relationships between three types of broad influence strategy (persuasive, assertive, and relationship based) and four dimensions of individual beliefs (cynicism, fate control, reward for application, and religiosity) were examined. Three of Project GLOBE's cultural values (in-group collectivism, uncertainty avoidance, and future orientation) were selected to investigate their direct effects on the rated effectiveness of influence strategies, and their possible interaction with dimensions of individual beliefs. Results showed that different dimensions of individual social beliefs predict the perceived effectiveness of the three types of influence strategy, and that cultural values can moderate the strength of the relationship between these dimensions of individual social beliefs and the perceived effectiveness of influence strategies
4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica
Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil.
El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país.
La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica.
Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas
Resilient Agility: A Necessary Condition for Employee and Organizational Sustainability
Resilient agility is a novel concept that refers to the combined resilience-agility capability that allows an actor to successfully perform in rapidly changing contexts. Change dynamics, at all levels, increase uncertainties and responsibilities for employees augmenting the need to strengthen the self via resilient agility. This study examines employee resilient agility as anteceded by supervisors’ safety, coworkers’ safety, workplace belongingness, job satisfaction, willingness to embrace organizational change, and creativity. Respondents are from multiple organizations, industries, and regions of the United States. Analyses were carried out utilizing PLS-SEM software. Findings indicate that supervisors’ safety, workplace belongingness, willingness to embrace organizational change, and creativity have substantial effects on explaining and understanding employees’ resilient agility. In contrast, the effects of coworkers’ safety were insignificant. This study (a) contributes to the nomological network of resilient agility by examining a set of its key antecedents and (b) suggests that drastic organizational restructuring (e.g., significant changes in the relative proportion of remote working during the COVID-19 pandemic) may negatively impact both relational-based constructs in organizations and employees’ ability to rapidly and effectively respond to change. Theoretical and practical implications as well as limitations and future research are discussed
Leadership Multiplicities Before and <i>During</i> the Post-Truth Era
Drawing from the ontology of the lack (Laclau and Mouffe 1985), aesthetic theory (Adorno 1997); practice theory (Bourdieu 2002), art perception theory (Bourdieu 1968), and storytelling theory (Boje 2001), we discuss leadership multiplicities and post-truth era phenomena. We conceptualize leadership as a heterogeneous field with an evolving incomplete set of contested narratives, at different development stages, entertained by different players. In the continuous re-occupation of the lack exists tensions, contradictions and conflicts within and between players’ narratives. This situation generates a large variability that requires acknowledgement, promotion, and some management. We relate our discussion to education. We suggest ways to create unity within diversity and resolve some of these contradictions and tensions. The concept of parallax (Zizek 2006), which offers a new gaze, illustrates how to configure sets of related leadership narratives