Effects of Cardiac Stem Cell on Postinfarction Arrhythmogenic Substrate.

Clinical data suggest that cardiosphere-derived cells (CDCs) could modify post-infarction scar and ventricular remodeling and reduce the incidence of ventricular tachycardia (VT). This paper assesses the effect of CDCs on VT substrate in a pig model of postinfarction monomorphic VT. We studied the effect of CDCs on the electrophysiological properties and histological structure of dense scar and heterogeneous tissue (HT). Optical mapping and histological evaluation were performed 16 weeks after the induction of a myocardial infarction by transient occlusion of the left anterior descending (LAD) artery in 21 pigs. Four weeks after LAD occlusion, pigs were randomized to receive intracoronary plus trans-myocardial CDCs (IC+TM group, n: 10) or to a control group. Optical mapping (OM) showed an action potential duration (APD) gradient between HT and normal tissue in both groups. CDCs increased conduction velocity (53 ± 5 vs. 45 ± 6 cm/s, p < 0.01), prolonged APD (280 ± 30 ms vs. 220 ± 40 ms, p < 0.01) and decreased APD dispersion in the HT. During OM, a VT was induced in one and seven of the IC+TM and control hearts (p = 0.03), respectively; five of these VTs had their critical isthmus located in intra-scar HT found adjacent to the coronary arteries. Histological evaluation of HT revealed less fibrosis (p < 0.01), lower density of myofibroblasts (p = 0.001), and higher density of connexin-43 in the IC+TM group. Scar and left ventricular volumes did not show differences between groups. Allogeneic CDCs early after myocardial infarction can modify the structure and electrophysiology of post-infarction scar. These findings pave the way for novel therapeutic properties of CDCs.

Modeling field scale nitrogen non-point source pollution (NPS) fate and transport: Influences from land management practices and climate.

The use of nitrogen (N) fertilizer marked the start of modern agriculture that boosted food production to help alleviate food shortages across the globe but at the cost of severe environmental issues and critical stress to the agroecosystem. This paper was aimed at determining the fate and transport of nitrite and ammonia under future climate projections by adapting the recommended land management practices that are supposed to reduce nitrate N in surface water to state government target. To accomplish these objectives, a fully-distributed physical-based hydrologic model, MIKE SHE, and a hydrodynamic river model, MIKE 11, were coupled with MIKE ECO-Lab to simulate the fate and transport of different forms of N in the agro-ecosystem in the Upper Sangamon River Basin (USRB). Twelve (12) combinations of land management and climate projections were simulated to evaluate the N fate and transport in the USRB from 2020 to 2050. Under the current land management, the nitrate concentration in surface water was expected to exceed the EPA limit of 10 ppm up to 2.5% of the days in the simulation period. Regulating the fertilizer application rates to approximately 50% of the current rate will ensure this limit will not be exceeded in the future. Implementing cover cropping alone can potentially decrease nitrate N concentrations by 33% in surface water under dry climate and in the saturated zone under future projections. By combining the cover cropping and regulated application rate management, the nitrate N concentration in the saturated zone was expected to decrease by 67% compared with historic baseline. The modeling framework developed and used in this study can help evaluate the effectiveness of different management schemes aimed at reducing future nutrient load in our surface water and groundwater.

A comprehensive modeling framework to evaluate soil erosion by water and tillage.

Soil erosion is significantly increased and accelerated by unsustainable agricultural activities, resulting in one of the major threats to soil health and water quality worldwide. Quantifying soil erosion under different conservation practices is important for watershed management and a framework that can capture the spatio-temporal dynamics of soil erosion by water is required. In this paper, a modeling framework that coupled physically based models, Water Erosion Prediction Project (WEPP) and MIKE SHE/MIKE 11, was presented. Daily soil loss at a grid-scale resolution was determined using WEPP and the transport processes were simulated using a generic advection dispersion equation in MIKE SHE/MIKE 11 models. The framework facilitated the physical simulation of sediment production at the field scale and transport processes across the watershed. The coupled model was tested using an intensively managed agricultural watershed in Illinois. The impacts of no-till practice on both sediment production and sediment yield were evaluated using scenario-based simulations with different fractions of no-till and conventional tillage combinations. The results showed that if no-till were implemented for all fields throughout the watershed, 76% and 72% reductions in total soil loss and sediment yield, respectively, can be achieved. In addition, if no-till practice were implemented in the most vulnerable areas to sediment production across the watershed, a 40% no-till implementation can achieve almost the same reduction as 100% no-till implementation. Based on the simulation results, the impacts of no-till practice are more prominent if implemented where it is most needed.

Características epidemiológicas de la tuberculosis en un hospital de referencia / Determinants of Smoking in Pregnant Women treated in Public Institutions in the Province of Tucumán, Argentina

Introducción: En la actualidad, la tuberculosis es la novena causa de muerte y la primera por enfermedades infecciosas. Según estimaciones hay 10 millones de nuevos casos de enfermos por año en todo el mundo con más de un millón de muertes anuales. El objetivo del presente trabajo es caracterizar los pacientes diagnosticados de tuberculosis y tratados en el Hospital Transito Cáceres de Allende de la Ciudad de Córdoba. Material y métodos: Se realizó un estudio retrospectivo, observacional, descriptivo, de corte transversal. Resultados: Se incluyeron 69 pacientes, 57,9% fueron hombres. El grupo etario más afectado fue entre los 26 y 65 años. El 35% no tenía trabajo, y de los que si tenían, una gran parte no tenía estabilidad laboral. Ocho pacientes tenían algún grado de inmunocompromiso, presentando solo 1 infección por HIV. No hubo casos de pacientes con resistencia a drogas antituberculosas. Conclusiones: Las características epidemiológicas de nuestros pacientes son similares a otras publicaciones de la región. Conocerlas nos permite tomar decisiones de manejo diario, tanto en diagnóstico y tratamiento, como en la prevención y control de foco para limitar la propagación de la misma.

Epidemiological Characteristics of Tuberculosis in a Reference Hospital

Introduction: At present, tuberculosis is the ninth cause of death, the first from infectious diseases. According to some estimates, there are 10 million new cases of ill people with tuberculosis per year throughout the world, with more than one million annual deaths. The objective of this study was to characterize patients diagnosed with tuberculosis who were treated in the Hospital Transito Cáceres de Allende of the city of Córdoba. Materials and Methods: We conducted a retrospective, observational, descriptive, cross-sectional study. Results: 57.9% of the 69 patients included in the study were male. The most affected age group was between 26 and 65 years. 35% did not have a job, and a large part of those who were employed did not have job stability. Eight patients were partially immunocompromised and there was only 1 case of HIV infection. There were no cases of antituberculous drug-resistant patients. Conclusions: The epidemiological characteristics of our patients are similar to other publications of the area. Knowing about them allows us to make decisions regarding daily management, both in terms of diagnosis and treatment, and also prevention and outbreakcontrol, in order to limit disease propagation.

Riparian erosion vulnerability model based on environmental features.

Riparian erosion is one of the major causes of sediment and contaminant load to streams, degradation of riparian wildlife habitats, and land loss hazards. Land and soil management practices are implemented as conservation and restoration measures to mitigate the environmental problems brought about by riparian erosion. This, however, requires the identification of vulnerable areas to soil erosion. Because of the complex interactions between the different mechanisms that govern soil erosion and the inherent uncertainties involved in quantifying these processes, assessing erosion vulnerability at the watershed scale is challenging. The main objective of this study was to develop a methodology to identify areas along the riparian zone that are susceptible to erosion. The methodology was developed by integrating the physically-based watershed model MIKE-SHE, to simulate water movement, and a habitat suitability model, MaxEnt, to quantify the probability of presences of elevation changes (i.e., erosion) across the watershed. The presences of elevation changes were estimated based on two LiDAR-based elevation datasets taken in 2009 and 2012. The changes in elevation were grouped into four categories: low (0.5 - 0.7 m), medium (0.7 - 1.0 m), high (1.0 - 1.7 m) and very high (1.7 - 5.9 m), considering each category as a studied "species". The categories' locations were then used as "species location" map in MaxEnt. The environmental features used as constraints to the presence of erosion were land cover, soil, stream power index, overland flow, lateral inflow, and discharge. The modeling framework was evaluated in the Fort Cobb Reservoir Experimental watershed in southcentral Oklahoma. Results showed that the most vulnerable areas for erosion were located at the upper riparian zones of the Cobb and Lake sub-watersheds. The main waterways of these sub-watersheds were also found to be prone to streambank erosion. Approximatively 80% of the riparian zone (streambank included) has up to 30% probability to experience erosion greater than 1.0 m. By being able to identify the most vulnerable areas for stream and riparian sediment mobilization, conservation and management practices can be focused on areas needing the most attention and resources.

Recubrimiento pulpar directo con hidroxiapatita fosfato tricálcico e hidróxido de calcio en perros / Dentin formation using materials like hidroxipatita, tricalcium phosphate in direct pulp recoverings in dogs

El propósito de este estudio fué evaluar la formación de un puente dentinal, utilizando materiales como la hidroxiapatita, el fosfato tricálcico e hidróxido de calcio, en recubrimientos pulpares directos; ya que estos materiales parecen promover la formación de dentina en el sitio de la exposición pulpar. Cinco perros adultos fueron usados para esta investigación. Se realizaron cavidades clase V en molares y premolares superiores e inferiores para un total de 30 unidades muestrales. Dos animales fueron sacrificados a los 14 días y los tres restantes a los 28 días, para observar la formación del puente dentinal. No hubo diferencia significativa entre los materiales, aunque la hidroxiapatita demostró mejores resultados en forma global