202 research outputs found

    Use of Cross-Species Amplification Markers for Pollen-Medicated Gene Flow Determination in \u3cem\u3eTrifolium Polymorphum\u3c/em\u3e Poiret

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    The species Trifolium polymorphum Poiret is endemic to Uruguay and is widespread in native grasslands throughout the country. Preliminary observations suggested that the aerial flowers are chasmogamous (open at maturity for potential cross-pollination) while the basal flowers are cleistogamous. Several approaches have been practised to determine the reproductive system of forage legumes by the aid of co-dominant markers (Real et al., 2004; Dalla Rizza et al., 2004). The aim of this study is to explore cross-species amplification as a quick approach to obtain co-dominant markers to study the breeding system of T. polymorphum

    X Encuentro Latinoamericano y del Caribe de Biotecnología Agropecuaria y XI Simposio REDBIO Argentina : Libro de Resúmenes

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    En REDBIO 2019 de «mayor productividad agrícola con menor huella ambiental» se reconoce que los sistemas agrícolas dependen de la interconexión de muchos elementos y procesos diferentes. El desafío mundial de la seguridad alimentaria es multidimensional, de las cuales sólo algunas son susceptibles de cambio a través de la ciencia y la innovación. La ciencia interactúa necesariamente con los sistemas sociales, económicos y ambientales. Las mejoras en la producción de cultivos alimentarios pueden provenir de la investigación científica, pero para que los cambios en los sistemas de producción se consideren sostenibles, deben tener en cuenta los tres elementos

    Differential parameters between cytosolic 2-Cys peroxiredoxins, PRDX1 and PRDX2

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    Peroxiredoxins are thiol-dependent peroxidases that function in peroxide detoxification and H2O2 induced signaling. Among the six isoforms expressed in humans, PRDX1 and PRDX2 share 97% sequence similarity, 77% sequence identity including the active site, subcellular localization (cytosolic) but they hold different biological functions albeit associated with their peroxidase activity. Using recombinant human PRDX1 and PRDX2, the kinetics of oxidation and hyperoxidation with H2O2 and peroxynitrite were followed by intrinsic fluorescence. At pH 7.4, the peroxidatic cysteine of both isoforms reacts nearly tenfold faster with H2O2 than with peroxynitrite, and both reactions are orders of magnitude faster than with most protein thiols. For both isoforms, the sulfenic acids formed are in turn oxidized by H2O2 with rate constants of ca 2 × 103 M−1 s−1 and by peroxynitrous acid significantly faster. As previously observed, a crucial difference between PRDX1 and PRDX2 is on the resolution step of the catalytic cycle, the rate of disulfide formation (11 s−1 for PRDX1, 0.2 s−1 for PRDX2, independent of the oxidant) which correlates with their different sensitivity to hyperoxidation. This kinetic pause opens different pathways on redox signaling for these isoforms. The longer lifetime of PRDX2 sulfenic acid allows it to react with other protein thiols to translate the signal via an intermediate mixed disulfide (involving its peroxidatic cysteine), whereas PRDX1 continues the cycle forming disulfide involving its resolving cysteine to function as a redox relay. In addition, the presence of C83 on PRDX1 imparts a difference on peroxidase activity upon peroxynitrite exposure that needs further study.Fil: Dalla Rizza, Joaquín. Universidad de la Republica; UruguayFil: Randall, Lía M.. Universidad de la Republica; UruguayFil: Santos, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Ferrer Sueta, Gerardo. Universidad de la Republica; UruguayFil: Denicola, Ana. Universidad de la República; Urugua

    Prediction of Postprandial Glycemic Exposure Utility of fasting and 2-h glucose measurements alone and in combination with assessment of body composition, fitness, and strength

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    OBJECTIVE —To determine the best predictors of total postprandial glycemic exposure and peak glucose concentrations in nondiabetic humans. RESEARCH DESIGN AND METHODS —Data from 203 nondiabetic volunteers who ingested a carbohydrate-containing mixed meal were analyzed. RESULTS —Fasting glucose and insulin concentrations were poor predictors of postprandial glucose area above basal ( R 2 = ∼0.07, P < 0.001). The correlation was stronger for 2-h glucose concentration ( R 2 = 0.55, P < 0.001) and improved slightly but significantly ( P < 0.001) with the addition of fasting glucose, insulin, age, sex, and body weight to the model ( r 2 = 0.58). The 2-h glucose concentration also predicted the peak glucose concentration ( R 2 = 0.37, P < 0.001) with strength of the prediction increasing ( P < 0.001) modestly with the addition of fasting glucose, insulin, age, sex, and body weight to the model ( R 2 = 0.48, P < 0.001). On the other hand, addition of measures of body function and composition did not improve prediction of total glycemic exposure or peak glucose concentration. CONCLUSIONS —Isolated measures of fasting or 2-h glucose concentrations alone or in combination with more complex measures of body composition and function are poor predictors of postprandial glycemic exposure or peak glucose concentration. This may explain, at least in part, the weak and at times inconsistent relationship between these parameters and cardiovascular risk

    Revisão das interações ecológicas da mosca Cochliomyia hominivorax e avaliação dos possíveis impactos ecológicos de sua erradicação no Uruguai

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    Controlling a pest species raises questions about the harmful effects its eradication could cause in ecosystems. Currently, in Uruguay are being analyzed strategies to eradicate the New World Screwworm (NWS), Cochliomyia hominivorax (Diptera: Calliphoridae), an obligatory ectoparasite that causes myiasis in warm-blooded vertebrates, including humans. The loss of a species implies a risk of secondary extinctions and cascading effects that depend on the ecological function of the species and the capacity of the rest of the species with which it interacts to compensate for its loss. To assess the ecological impact of the NWS eradication, we analyzed its ecological redundancy, its effect as an indirect regulatory agent for other species, and its participation in critical ecosystem functions. We conclude that the NWS presents high functional redundancy in most ecological interactions. It does not play an essential role as a regulatory agent of other species and does not play an important role in critical ecosystem functions. Without ignoring the information gaps that certainly exist about the ecological interactions network of the NWS in Uruguay, we estimate that its eradication is unlikely to cause secondary extinctions or cascading effects in the networks it integrates. In order to timely detect possible impacts during the course of the program, it is recommended to monitor the ecosystems using indicators related to direct and indirect partners in the ecological interactions of the NWS.El control de una especie plaga genera interrogantes sobre los efectos nocivos que su erradicación podría causar en los ecosistemas. Actualmente, en Uruguay se analizan estrategias para erradicar la mosca de la bichera (MB), Cochliomyia hominivorax (Diptera: Calliphoridae), un ectoparásito obligatorio que causa miasis en vertebrados de sangre caliente, incluidos los humanos. La pérdida de una especie supone un riesgo de extinciones secundarias y efectos en cascada que dependen de la función ecológica de la especie que se pierde y la capacidad del resto de las especies con las que interactúa para compensar su pérdida. Para evaluar el impacto ecológico de la erradicación de la MB analizamos su redundancia ecológica, su efecto como agente regulador indirecto de otras especies y su participación en funciones críticas de los ecosistemas. Concluimos que la MB presenta alta redundancia funcional en la mayoría de sus interacciones ecológicas, no juega un papel importante como agente regulador de otras especies y no juega un papel importante en funciones ecosistémicas críticas. Sin desconocer los vacíos de información que ciertamente existen sobre la red de interacciones ecológicas de la MB en Uruguay, estimamos que es poco probable que su erradicación cause extinciones secundarias o efectos en cascada en las redes de interacciones ecológicas que integra. A fin de detectar oportunamente eventuales impactos durante el curso del programa, se recomienda monitorear los ecosistemas utilizando indicadores relacionados con socios directos e indirectos en las interacciones ecológicas de la MB.O controle de uma espécie praga levanta questões sobre os efeitos nocivos que a erradicação pode causar nos ecossistemas. Atualmente, no Uruguai estão sendo analisadas estratégias de controle para erradicar a mosca da bicheira (MB), Cochliomyia hominivorax (Diptera: Calliphoridae), um ectoparasita obrigatório que causa miíase em vertebrados de sangue quente, incluindo o homem. A perda de uma espécie implica um risco de extinções secundárias e efeitos em cascata que dependem da função ecológica da espécie que se perde e da capacidade do resto das espécies com as quais interage para compensar a sua perda. Para avaliar o impacto ecológico da erradicação da MB, analisamos sua redundância ecológica, seu efeito como agente regulador indireto para outras espécies e sua participação em funções críticas do ecossistema. Concluímos que a MB apresenta alta redundância funcional na maioria de suas interações ecológicas, não desempenha um papel importante como agente regulador de outras espécies e não desempenha um papel importante em funções críticas do ecossistema. Sem ignorar as lacunas de informação que certamente existem sobre a rede de interações ecológicas do NWS no Uruguai, estimamos que é improvável que sua erradicação cause extinções secundárias ou efeitos em cascata nas redes de interações ecológicas que integra. Para detectar oportunamente possíveis impactos durante o curso do programa, recomenda-se monitorar os ecossistemas usando indicadores relacionados a parceiros diretos e indiretos nas interações ecológicas da MB

    Use of Genuine Sources of Ergot Resistance in Species of the \u3ci\u3edilatata\u3c/i\u3e Group of \u3ci\u3ePaspalum\u3c/i\u3e

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    Paspalum dilatatum Poir. (dallisgrass) is an excellent C4 forage for summer production, highly productive with a wide distribution within warm-temperate regions. P. dilatatum is native to South America with special relevance for milk and meat production since its forage quality is superior to that of other C4 forage grasses and it shows tolerance to frost and water stress. In situations of temperate and warm temperate climate, the presence of these species plays a key role in the ecological stability of the system due to the complementarity of the growth cycles between winter and summer grasses. Claviceps paspali (ergot) is a fungus that mainly parasitizes Paspalum spp., generating a structure called sclerotia, in which indole-diterpenoid alkaloids are isolated. Despite the excellent forage characteristics of Paspalum species, there is a need for the generation of varieties able to overcome two major limitations that were identified early on in this species, such as ergot susceptibility and seed production. With this objective, selected genotypes were crossed between apomictic and sexual species of different ploidy using P. malacophyllum as a source of immunity. Immunity to ergot has been evaluated in the field for two years in different representative regions of Uruguay and the accessions that did not get sick were selected as pollen donors. Crosses made with P. flavescens showed a germination percentage ranging between 1.7 and 7.09, while in P. dilatatum var. Chirú the range was reduced between 0.99 and 1.25 according to the employed parents. The hybrid nature of the progeny is being verified by microsatellites and functional markers associated with immunity and DNA content estimated by flow cytometry. This work aims to generate the basis to transfer immunity from P. malacophyllum in selected genotypes of Paspalum species predominant in Pampa biome and to improve seed production

    Minimal model estimation of glucose absorption and insulin sensitivity from oral test : validation with a tracer method

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    Measuring insulin sensitivity during the physiological milieu of oral glucose perturbation, e.g., a meal or an oral glucose tolerance test, would be extremely valuable but difficult since the rate of appearance of absorbed glucose is unknown. The reference method is a tracer two-step one: first, the rate of appearance of glucose (R(a meal)(ref)) is reconstructed by employing the tracer-to-tracee ratio clamp technique with two tracers and a model of non-steady-state glucose kinetics; next, this R(a meal)(ref) is used as the known input of a model describing insulin action on glucose kinetics to estimate insulin sensitivity (SI(ref)). Recently, a nontracer method based on the oral minimal model (OMM) has been proposed to estimate simultaneously the above quantities, denoted R(a meal) and SI, respectively, from plasma glucose and insulin concentrations measured after an oral glucose perturbation. This last method has obvious advantages over the tracer method, but its domain of validity has never been assessed against a reference method. It is thus important to establish whether or not the "nontracer" R(a meal) and SI compare well with the "tracer" R(a meal)(ref) and SI(ref). We do this comparison on a database of 88 subjects, and it is very satisfactory: R(a meal) profiles agree well with the R(a meal)(ref) and correlation of SI(ref) with SI is r = 0.86 (P < 0.0001). We conclude that OMM candidates as a reliable tool to measure both the rate of glucose absorption and insulin sensitivity from oral glucose tests without employing tracers

    Codes of Commitment to Crime and Resistance: Determining Social and Cultural Factors over the Behaviors of Italian Mafia Women

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    This article categorizes thirty-three women in four main Italian Mafia groups and explores social and cultural behaviors of these women. This study introduces the feminist theory of belief and action. The theoretical inquiry investigates the sometimes conflicting behaviors of women when they are subject to systematic oppression. I argue that there is a cultural polarization among the categorized sub-groups. Conservative radicals give their support to the Mafia while defectors and rebels resist the Mafia. After testing the theory, I assert that emancipation of women depends on the strength of their beliefs to perform actions against the Mafiosi culture
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