Simulación numérica aplicada a la interacción agua subterránea-humedales en la Llanura Pampeana, Provincia de Buenos Aires

En la llanura pampeana los cuerpos de agua superficial son parte activa del sistema de flujo del agua subterránea. La laguna La Salada y su área de influencia se ubican en las cercanías de la localidad La Dulce (Provincia de Bs. As.), sobre la divisoria sur de la cuenca del Río Quequén. El objetivo del trabajo es cuantificar la interacción entre los cuerpos de agua de la laguna, acuífero y río y establecer el balance global de masas a través de la modelación numérica. Los resultados de la simulación del flujo muestran en régimen estacionario el comportamiento efluente – influente de la laguna y el flujo de agua subterránea hacia el río. La simulación del régimen transitorio muestra un buen ajuste entre los niveles observados y calculados durante el periodo 2007-2010 en un freatímetro ubicado entre la laguna y el río. Los términos del balance global de masas incluyen precipitación 116 hm3/año, evapotranspiración 82.1 hm3/año, escurrimiento superficial 1.8 hm3/año, evaporación en la laguna 5 hm3/año, recarga del acuífero 16 hm3/año, descarga de agua subterránea a la laguna 6 hm3/año, descarga de agua subterránea al río 9.5 hm3/año y extracción para consumo urbano 0.5 hm3/año. La integración de herramientas numéricas de simulación del flujo con estudios previos de modelación hidrogeoquímica permitió alcanzar resultados consistentes de la evaporación en la laguna con respecto al valor obtenido por el balance hídrico. La metodología utilizada constituye un aporte al abordaje de estudios cuantitativos sobre la interacción aguas subterráneas – aguas superficiales en la llanura pampeana.In the Pampa plain the surface water bodies are integral parts of groundwater flow systems. La Salada wetland is located on the watershed of the Quequén River basin, next to La Dulce town (Buenos Aires Province).The aim of the present study is both to quantify the wetland - aquifer – river interactions and to establish the mass global balance through the numerical modeling. Results of flow simulation in the steady regime show the effluent-influent behavior of the wetland and the discharge of groundwater to the Quequén River. The transient regime shows a noticeable fitness observed between the simulated and the measured values compared to the daily record piezometer (2007-2010). Mass global balance comprise precipitation 116 hm3/year, evapotranspiration 82.1 hm3/year, runoff 1.8 hm3/año, evaporation in the wetland 5 hm3/year, recharge to the aquifer 16 hm3/ year, groundwater discharge to the wetland 6 hm3/ year, groundwater discharge to the river 9.5 hm3/ year y extraction for human consumption 0.5 hm3/ year. The joint tools of numerical simulation of flow and previous studies of hydrogeochemical modeling allow reach similar results for the evaporation in the wetland compared to those from the water balance. The study constitutes a contribution to the assessment of the groundwater – surface water interactions in the Pampa plain

The role of PKCzeta in cord blood T-cell maturation towards Th1 cytokine profile and its epigenetic regulation by fish oil

While immunodeficiency of immaturity of the neonate has been considered important as the basis for unusual susceptibility to infection, it has also been recognized that the ability to progress from an immature Th2 cytokine predominance to a Th1 profile has relevance in determining whether children will develop allergy, providing an opportunity for epigenetic regulation through environmental pressures. However, this notion remains relatively unexplored. Here, we present evidence that there are two major control points to explain the immunodeficiency in cord blood (CB) T-cells, a deficiency in interleukin (IL)-12 (IL-12) producing and IL-10 overproducing accessory cells, leading to a decreased interferon γ (IFNγ) synthesis and the other, an intrinsic defect in T-cell protein kinase C (PKC) ζ (PKCζ) expression. An important finding was that human CB T-cells rendered deficient in PKCζ, by shRNA knockdown, develop into low tumour necrosis factor α (TNFα) and IFNγ but increased IL-13 producing cells. Interestingly, we found that the increase in PKCζ levels in CB T-cells caused by prenatal supplementation with fish oil correlated with modifications of histone acetylation at the PKCζ gene (PRKCZ) promoter. The data demonstrate that PKCζ expression regulates the maturation of neonatal T-cells into specific functional phenotypes and that environmental influences may work via PKCζ to regulate these phenotypes and disease susceptibility.Hani Harb, James Irvine, Manori Amarasekera, Charles S. Hii, Dörthe A. Kesper, YueFang Ma, Nina D′Vaz, Harald Renz, Daniel P. Potaczek, Susan L. Prescott and Antonio Ferrant

Finding a partner in the ocean: molecular and evolutionary bases of the response to sexual cues in a planktonic diatom

Microalgae play a major role as primary producers in aquatic ecosystems. Cell signalling regulates their interactions with the environment and other organisms, yet this process in phytoplankton is poorly defined. Using the marine planktonic diatom Pseudo-nitzschia multistriata, we investigated the cell response to cues released during sexual reproduction, an event that demands strong regulatory mechanisms and impacts on population dynamics. We sequenced the genome of P. multistriata and performed phylogenomic and transcriptomic analyses, which allowed the definition of gene gains and losses, horizontal gene transfers, conservation and evolutionary rate of sex-related genes. We also identified a small number of conserved noncoding elements. Sexual reproduction impacted on cell cycle progression and induced an asymmetric response of the opposite mating types. G protein-coupled receptors and cyclic guanosine monophosphate (cGMP) are implicated in the response to sexual cues, which overall entails a modulation of cell cycle, meiosis-related and nutrient transporter genes, suggesting a fine control of nutrient uptake even under nutrient-replete conditions. The controllable life cycle and the genome sequence of P. multistriata allow the reconstruction of changes occurring in diatoms in a key phase of their life cycle, providing hints on the evolution and putative function of their genes and empowering studies on sexual reproduction

Finding a partner in the ocean: molecular and evolutionary bases of the response to sexual cues in a planktonic diatom

Microalgae play a major role as primary producers in aquatic ecosystems. Cell signalling regulates their interactions with the environment and other organisms, yet this process in phytoplankton is poorly defined. Using the marine planktonic diatom Pseudo-nitzschia multistriata, we investigated the cell response to cues released during sexual reproduction, an event that demands strong regulatory mechanisms and impacts on population dynamics. We sequenced the genome of P. multistriata and performed phylogenomic and transcriptomic analyses, which allowed the definition of gene gains and losses, horizontal gene transfers, conservation and evolutionary rate of sex-related genes. We also identified a small number of conserved noncoding elements. Sexual reproduction impacted on cell cycle progression and induced an asymmetric response of the opposite mating types. G protein-coupled receptors and cyclic guanosine monophosphate (cGMP) are implicated in the response to sexual cues, which overall entails a modulation of cell cycle, meiosis-related and nutrient transporter genes, suggesting a fine control of nutrient uptake even under nutrient-replete conditions. The controllable life cycle and the genome sequence of P. multistriata allow the reconstruction of changes occurring in diatoms in a key phase of their life cycle, providing hints on the evolution and putative function of their genes and empowering studies on sexual reproduction

Generalized cost-effectiveness analysis of a package of interventions to reduce cardiovascular disease in Buenos Aires, Argentina

<p>Abstract</p> <p>Background</p> <p>Chronic diseases, represented mainly by cardiovascular disease (CVD) and cancer, are increasing in developing countries and account for 53% of chronic diseases in Argentina. There is strong evidence that a reduction of 50% of the deaths due to CVD can be attributed to a reduction in smoking, hypertension and hypercholesterolemia. Generalized cost-effectiveness analysis (GCE) is a methodology designed by WHO to inform decision makers about the extent to which current or new interventions represent an efficient use of resources. We aimed to use GCE analysis to identify the most efficient interventions to decrease CVD.</p> <p>Methods</p> <p>Six individual interventions (treatment of hypertension, hypercholesterolemia, smoking cessation and combined clinical strategies to reduce the 10 year CVD Risk) and two population-based interventions (cooperation between government, consumer associations and bakery chambers to reduce salt in bread, and mass education strategies to reduce hypertension, hypercholesterolemia and obesity) were selected for analysis. Estimates of effectiveness were entered into age and sex specific models to predict their impact in terms of age-weighted and discounted DALYs saved (disability-adjusted life years). To translate the age- and sex-adjusted incidence of CVD events into health changes, we used risk model software developed by WHO (PopMod). Costs of services were measured in Argentine pesos, and discounted at an annual rate of 3%. Different budgetary impact scenarios were explored.</p> <p>Results</p> <p>The average cost-effectiveness ratio in argentine pesos (ARS$) per DALY for the different interventions were: (i) less salt in bread$151; (ii) mass media campaign $547; (iii) combination drug therapy provided to subjects with a 20$3,599, $4,113 and$4,533, respectively; (iv) high blood pressure (HBP) lowering therapy $7,716; (v) tobacco cessation with bupropion$ 33,563; and (iv) high-cholesterol lowering therapy with statins $ 70,994.</p> <p>Conclusion</p> <p>Against a threshold of average per capita income in Argentina, the two selected population-based interventions (lowering salt intake and health education through mass-media campaigns) plus the modified polypill strategy targeting people with a 20% or greater risk were cost-effective. Use of this methodology in developing countries can make resource-allocation decisions less intuitive and more driven by evidence.</p

Desigualdades en la distribución de factores de riesgo en enfermedades cardiovasculares en la Argentina: un estudio a partir de la Encuesta Nacional de Factores de Riesgo (ENFR) de 2005, 2009 y 2013

Background: Cardiovascular health inequalities have been documented in the literature in both developed and undeveloped countries and there is an inverse association between the incidence and mortality for specific cause of cardiovascular disease and levels of income, education and employment. Objective: The aim of this study was to identify the existence of inequalities in the prevalence of risk factors by socioeconomic status in Argentina. Methods: Data from the 2005, 2009 and 2013 National Risk Factor Surveys (NRFS) were analyzed. The prevalence of obesity, smoking, hypertension and cholesterol were studied. Differences for each risk factor were estimated in relation to socioeconomic status (measured by education, income and health coverage). The independent association between socioeconomic status and risk factors was assessed using logistic regression models. Results: Educational level was inversely associated with the prevalence of obesity (p<0.01), hypercholesterolemia (p<0.01), hypertension (p<0.01) and smoking (p<0.05) and the effect varied by gender and age group. Income level was significantly and inversely associated with the prevalence of hypertension (p<0.01). The temporal evolution of inequalities indicates there was no attenuation between surveys and, on the contrary, it showed an increase in smoking gaps. Conclusions: Deep inequalities were recorded in the distribution of cardiovascular risk factors by educational level. Groups with high burden of risk factors are vulnerable populations upon which preventive policies should be targeted.Introducción: Las desigualdades en salud cardiovascular se han documentado en la literatura tanto en países desarrollados como no desarrollados y existe una asociación inversa entre la incidencia y mortalidad por causa específica de enfermedades cardiovasculares y los niveles de ingreso, educación y empleo. Objetivo: Identificar la existencia de desigualdades en la prevalencia de factores de riesgo por nivel socioeconómico en la Argentina. Material y métodos: Análisis de los datos de la Encuesta Nacional de Factores de Riesgo (ENFR) de 2005, 2009 y 2013. Se estudió la prevalencia de obesidad, tabaquismo, hipertensión arterial y colesterol. Se estimaron las brechas para cada factor de riesgo en relación con el nivel socioeconómico (medido con educación, ingreso y cobertura de salud). La asociación independiente entre nivel socioeconómico y factores de riesgo se evaluó con modelos de regresión logística. Resultados: El nivel educativo se asoció inversamente con la prevalencia de obesidad (p < 0,01), hipercolesterolemia (p < 0,01), hipertensión arterial (p < 0,01) y tabaquismo (p < 0,05) y el efecto varió por grupos de edad y sexo. El nivel de ingreso se asoció significativamente y de manera inversa con la prevalencia de hipertensión (p < 0,01). La evolución temporal de las desigualdades indica que no hubo atenuación de estas entre las encuestas y, por el contrario, muestra un incremento en las brechas de tabaquismo. Conclusiones: Se registraron profundas desigualdades en la distribución de factores de riesgo cardiovascular por niveles educativos. Los grupos con elevada carga de factores de riesgo constituyen poblaciones vulnerables sobre las cuales deberían orientarse políticas preventivasFacultad de Ciencias Económica