Ciencia y desertificación en América Latina

Los problemas de desertificación en América Latina y El Caribe son graves y afectan las bases productivas y la sociedad de prácticamente todos los países, con situaciones específicas de índole natural, socioeconómica y política, que tienden a agravar, profundizar y extender los efectos de la pobreza. Esta situación aún no ha sido estudiada suficientemente, y menos aún medidas y valoradas sus consecuencias económicas y sociales. En 2008, con el apoyo del Gobierno de Brasil, surge la ?Iniciativa de América Latina y El Caribe en Ciencia y Técnica en Desertificación? (ILACCT). Se discuten en este trabajo la oferta, problemas y necesidades de ciencia y técnica en la Región, así como los antecedentes de creación de la ILACCT, sus objetivos y temas centrales, alcances y posibilidades. Se espera de este modo aportar a consolidar el proceso iniciado para poner en valor las contribuciones de la ciencia y de la tecnología en el conocimiento de los procesos de desertificación y el manejo sustentable de la tierra, para ayudar a los decisores a la formulación de políticas proactivas y su control de gestión en la lucha contra la desertificación.The problems of desertification in Latin America and the Caribbean are serious and affect the production bases and societies of virtually every country, with specific situations of a natural, socioeconomic and political kind, which tend to aggravate, deepen and extend the effects of poverty. This situation has not yet been sufficiently studied, and even less have their economic and social consequences been measured and assessed. In 2008, with the support of Brazil’s government, there arises the “Initiative of Latin America and the Caribbean in Science and Technology in Desertification” (ILACCT). The offer, problems and necessities of science and technology in the Region are discussed in this work, as well as the background to the creation of the ILACCT, its objectives and key issues, scope and possibilities. In this manner, it is expected to contribute to strengthening the process started, so as to add value to the contributions of science and technology to the knowledge of desertification processes and of a sustainable management of land, aiming to help decision makers develop proactive policies and their management control in the combat against desertification.Fil: Abraham, Elena Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Matallo, Heitor. Convención de Naciones Unidas de Lucha contra la Desertificación y la Sequía; FranciaFil: De Lima, J. R.. Convención de Naciones Unidas de Lucha contra la Desertificación y la Sequía; Franci

Metabolic, cardiac and renal effects of the slow hydrogen sulfide-releasing molecule GYY4137 during resuscitated septic shock in swine with pre-existing coronary artery disease

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Published Ahead of Print, 19 January 2017Decreased levels of endogenous hydrogen sulfide (H2S) contribute to atherosclerosis, whereas equivocal data are available on H2S effects during sepsis. Moreover, H2S improved glucose utilization in anaesthetized, ventilated, hypothermic mice, but normothermia and/or sepsis blunted this effect. The metabolic effects of H2S in large animals are controversial. Therefore, we investigated the effects of the H2S donor GYY4137 during resuscitated, fecal peritonitis-induced septic shock in swine with genetically and diet-induced coronary artery disease (CAD). 12 and 18 hours after peritonitis induction, pigs received either GYY4137 (10 mg kg, n = 9) or vehicle (n = 8). Before, at 12 and 24 hours of sepsis, we assessed left ventricular (pressure-conductance catheters) and renal (creatinine clearance, blood NGAL levels) function. Endogenous glucose production and glucose oxidation were derived from the plasma glucose isotope and the expiratory CO2/CO2 enrichment during continuous i.v. 1,2,3,4,5,6-C6-glucose infusion. GYY4137 significantly increased aerobic glucose oxidation, which coincided with higher requirements of exogenous glucose to maintain normoglycemia, as well as significantly lower arterial pH and decreased base excess. Apart from significantly lower cardiac eNOS expression and higher troponin levels, GYY4137 did not significantly influence cardiac and kidney function or the systemic inflammatory response. During resuscitated septic shock in swine with CAD, GYY4137 shifted metabolism to preferential carbohydrate utilization. Increased troponin levels are possibly due to reduced local NO availability. Cautious dosing, the timing of GYY4137 administration and interspecies differences most likely account for the absence of any previously described anti-inflammatory or organ-protective effects of GYY4137 in this model

Subdoses de glyphosate como ferramenta na produção de ácido chiquímico por Brachiaria plantaginea (Link) Hitchc.

Resumo: Periodicamente a humanidade é assolada por pandemias de gripe com consequências fatais. Dessa forma, o desenvolvimento de medidas eficazes para combater as viroses é de crucial importância para a saúde humana. O fosfato de oseltamivir é um potente inibidor viral produzido a partir do ácido chiquímico e extraído da semente de llicium verum sua mais importante fonte natural. Tendo como sítio de ação a enzima 5-enolpiruvilchiquimato-3-fosfato sintae (EPSPs), glyflosate é o único composto capaz de inibir a sua atividade com o consequente acúmulo do ácido chiquímico pelos vegetais. Plantas de B. plantaginea foram pulverizadas com subdoses de glyflosate determinado-se o teor de ácido chiquímico na massa seca dessas plantas por HPLC aos 0, 3, 6, 9 e 12 dias após aplicação do herbicida. Os resultados mostraram que a aplicação de 36 g.ha-1 de equivalente ácido chiquímico quando comparada com os demais tratamentos nas diferentes épocas de amostragem, alcançando um máximo de concentração 6 dias após sua aplicação nas plantas de B. plantaginea, evidenciando o potencial dessa planta como fonte de ácido chiquímico para a produção de fosfato de oseltamivir quando tratada com esse herbicida

Effects of pretreatment hypothermia during resuscitated porcine hemorrhagic shock

OBJECTIVES: Accidental hypothermia increases mortality and morbidity after hemorrhage, but controversial data are available on the effects of therapeutic hypothermia. Therefore, we tested the hypothesis whether moderate pretreatment hypothermia would beneficially influence organ dysfunction during long-term, porcine hemorrhage and resuscitation. DESIGN: Prospective, controlled, randomized study. SETTING: University animal research laboratory. SUBJECTS: Twenty domestic pigs of either gender. INTERVENTIONS: Using an extracorporeal heat exchanger, anesthetized and instrumented animals were maintained at 38 degrees C, 35 degrees C, or 32 degrees C core temperature and underwent 4 hours of hemorrhage (removal of 40% of the blood volume and subsequent blood removal/retransfusion to maintain mean arterial pressure at 30 mm Hg). Resuscitation comprised of hydroxyethyl starch and norepinephrine infusion titrated to maintain mean arterial pressure at preshock values. MEASUREMENTS AND MAIN RESULTS: Before, immediately at the end of, and 12 and 22 hours after hemorrhage, we measured systemic and regional hemodynamics (portal vein, hepatic and right kidney artery ultrasound flow probes) and oxygen transport, and nitric oxide and cytokine production. Hemostasis was assessed by rotation thromboelastometry. Postmortem biopsies were analyzed for histomorphology (hematoxylin and eosin staining) and markers of apoptosis (kidney Bcl-xL and caspase-3 expression). Hypothermia at 32 degrees C attenuated the shock-related lactic acidosis but caused metabolic acidosis, most likely resulting from reduced carbohydrate oxidation. Although hypothermia did not further aggravate shock-related coagulopathy, it caused a transitory attenuation of kidney and liver dysfunction, which was ultimately associated with reduced histological damage and more pronounced apoptosis. CONCLUSIONS: During long-term porcine hemorrhage and resuscitation, moderate pretreatment hypothermia was associated with a transitory attenuation of organ dysfunction and less severe histological tissue damage despite more pronounced metabolic acidosis. This effect is possibly due to a switch from necrotic to apoptotic cell death, ultimately resulting from reduced tissue energy deprivation during the shock phase

Effects of the PPAR-β/δ agonist GW0742 during resuscitated porcine septic shock.

BACKGROUND: In un-resuscitated rodent models of septic shock, the peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ) agonist GW0742 improved visceral organ function. Therefore, we tested the hypothesis whether GW0742 would attenuate kidney injury during long-term, resuscitated, porcine polymicrobial septic shock. METHODS: Six, 12, and 18 h after the induction of fecal peritonitis by inoculation of autologous feces, anesthetized, mechanically ventilated, and instrumented male pigs with pre-existing atherosclerosis resulting from familial hypercholesteremia and atherogenic diet randomly received either vehicle (dimethyl sulfoxide, n = 12) or GW0742 (n = 10). Resuscitation comprised hydroxyethyl starch and norepinephrine infusion titrated to maintain mean arterial pressure at baseline values. RESULTS: Despite aggressive fluid resuscitation, fecal peritonitis was associated with arterial hypotension requiring norepinephrine infusion, ultimately resulting in progressive lactic acidosis and acute kidney injury. GW0742 did not beneficially affect any parameter of systemic and regional hemodynamics, gas exchange, metabolism, or organ function. The parameters of inflammation, oxidative and nitrosative stress, and organ injury (post-mortem analysis for histomorphology and markers of apoptosis) were not influenced either. Immunohistochemistry of pre-shock kidney biopsies from a previous study in this swine strain showed markedly lower PPAR-β/δ receptor expression than in healthy animals. CONCLUSIONS: In swine with pre-existing atherosclerosis, the PPAR-β/δ agonist GW0742 failed to attenuate septic shock-induced circulatory failure and kidney dysfunction, most likely due to reduced receptor expression coinciding with cardiovascular and metabolic co-morbidity