Evaluación genotóxica del etopósido (vp-16) en cultivos celulares estimulados con fitohemaglutinina

Investigar la frecuencia y tipo de rearreglos cromosómicos inducidos in vitro por el VP16, construir un mapa de las bandas cromosómicas más afectadas por el medicamento y definir si existe o no una respuesta diferencial entre los individuos analizados

N-enhancement in GN-z11: First evidence for supermassive stars nucleosynthesis in proto-globular clusters-like conditions at high redshift ?

Unusually high N/O abundances were recently reported for a very compact, intensively star-forming object GN-z11 at z=10.6 from JWST/NIRSpec observations. We present an empirical comparison with the C, N, and O abundance ratios in Galactic globular clusters (GCs) over a large metallicity range. We show that hot hydrogen-burning nucleosynthesis within supermassive stars (SMS) formed through runaway collisions can consistently explain the observed abundances ratio in GN-z11 and in GCs. This suggests that a proto-globular cluster hosting a SMS could be at the origin of the strong N-enrichment in GN-z11. Our model predicts the behavior of N/O, C/O, and Ne/O ratios as a function of metallicity, which can be tested if high-z objects similar to GN-z11 are detected with JWST in the future. Further studies and statistics will help differentiate the proto-GC scenario from the Wolf-Rayet scenario that we quantify with a population synthesis model, and shed more light on this peculiar object.Comment: Submitted to A&A Letter

Evaluación de compost a base de residuos de la industria azucarera con gallinaza y estiércol bovino

El uso de compost producido a base de residuos de industria azucarera y de la cría de animales es una alternativa para corregir la fertilidad del suelo, reciclar los nutrientes y minimizar procesos de contaminación por la deposición inadecuada de los mismos. El experimento tiene como objetivo evaluar dosis de compost a base de residuos de la industria azucarera como mejorador de las características químicas del suelo. El experimento tuvo un arreglo factorial, siendo los factores, tipos y dosis de compost. El compost fue a base de residuos de la industria azucarera con estiércol bovino (C-EB) y con gallinaza (C-G), las dosis evaluadas de compost fueron 0; 2,11; 4,23; 6,34; 8,45; 10,56; 12,68 t ha-1. El experimento se realizó en invernadero en la Facultad de Ciencias Agrarias utilizando macetas de 5 L con 7,1 kg de suelo. En los mismos fue sembrado trigo como planta indicadora, siendo dispuestos los tratamientos en bloques completos al azar. El experimento fue conducido por tres meses y el trigo por 60 días. Las mediciones en el trigo y en las propiedades químicas del suelo fueron sometidas a análisis de varianza. En las propiedades químicas del suelo el fósforo presentó diferencia significativas con la aplicación de compost (C-G), a dosis de 12,68 t ha-1 alcanzó un máximo de 21,22 mg kg-1 se ajustó a una ecuación lineal (y =1,4752x+0,9223) con coeficiente de determinación (R² = 96 %), que indicó un aumento por cada tonelada adicional de Gallinaza.; el magnesio presento diferencia entre los tipos de compost siendo superior en el compost (C-G); las variables de Ca+2, Mg+2, K+, conductividad eléctrica y pH no presentaron diferencias significativas. La materia seca área y radicular presentaron diferencias significativas para ambos compost, alcanzando un peso de 20,00 y 11,55g respectivamente con la aplicación de 8,45 t ha-1 de C-EB. En conclusión los abonos orgánicos combinados con los residuos de la industria azucarera son una alternativa viable para la producción orgánicaFil: Bobadilla Galeano, Silvia P.. Universidad Nacional de Asunción (Paraguay)Fil: González, Alba L.. Universidad Nacional de Asunción (Paraguay)Fil: Leguizamón Rojas, Carlos A. . Universidad Nacional de Asunción (Paraguay)Fil: Zacarias Servin, Doralicia. Universidad Nacional de Asunción (Paraguay

Comparación del comportamiento glucémico de cuatro fórmulas nutricionales específicas para diabéticos mediante el uso de monitoreo continuo de glucosa

Introducción: Las fórmulas líquidas nutricionales son consideradas alimentos que dadas sus características aseguran un aporte de macro y micronutrientes estándar que pueden sustituir o complementar la alimentación de los pacientes con diabetes. No existen comparaciones frente a frente que evalúen el perfil glucémico entre fórmulas nutricionales específicas para diabéticos. Materiales y métodos: Se realizó un ensayo clínico cruzado, con el fin de comparar el comportamiento glucémico y la variabilidad glucémica entre cuatro fórmulas nutricionales comerciales específicas para diabéticos y un desayuno estándar en 10 sujetos con diabetes mellitus tipo 2, mediante el uso de un sistema de monitoreo continuo de glucosa. Se calculó el promedio, desviación estándar y el área bajo la curva en hiperglucemia de cada una de las fórmulas. Además se determinó el coeficiente de variación y otras medidas de variabilidad. Se analizó el delta de glucosa intersticial cada cinco minutos estratificado para cada fórmula nutricional. Resultados: El promedio de glucosa para el desayuno control fue 146,7± 44,3 mg/dl, Ensoy Diabetes® 129,6 ±25,1mg/ dl, Enterex DBT® 129,6± 26,8 mg/dl, Glucerna SR® 131,5± 31,7 mg/dl y Prowhey DM® 131,7± 30,7 mg/dl. Las cuatro fórmulas nutricionales tuvieron menor AUC en un periodo de cuatro horas (posabsortivo) respecto a un desayuno estándar (p<0,001), generando menores excursiones glucémicas y reafirmando su menor índice glucémico. Conclusiones: Las cuatro fórmulas nutricionales específicas para diabéticos evaluadas en nuestro estudio fueron superiores en comportamiento y variabilidad glucémica a un desayuno estándar en población diabética. Ensoy Diabetes® mostró menor AUC frente a Glucerna SR®, hallazgo que podría ser explicado por el menor aporte real de carbohidratos de Ensoy Diabetes® (17 vs 22,4 g)

Partial loss of actin nucleator actin-related protein 2/3 activity triggers blebbing in primary T lymphocytes

T lymphocytes utilize amoeboid migration to navigate effectively within complex microenvironments. The precise rearrangement of the actin cytoskeleton required for cellular forward propulsion is mediated by actin regulators, including the actin‐related protein 2/3 (Arp2/3) complex, a macromolecular machine that nucleates branched actin filaments at the leading edge. The consequences of modulating Arp2/3 activity on the biophysical properties of the actomyosin cortex and downstream T cell function are incompletely understood. We report that even a moderate decrease of Arp3 levels in T cells profoundly affects actin cortex integrity. Reduction in total F‐actin content leads to reduced cortical tension and disrupted lamellipodia formation. Instead, in Arp3‐knockdown cells, the motility mode is dominated by blebbing migration characterized by transient, balloon‐like protrusions at the leading edge. Although this migration mode seems to be compatible with interstitial migration in three‐dimensional environments, diminished locomotion kinetics and impaired cytotoxicity interfere with optimal T cell function. These findings define the importance of finely tuned, Arp2/3‐dependent mechanophysical membrane integrity in cytotoxic effector T lymphocyte activities

Nietzsche’s Epistemic Perspectivism

Nietzsche offers a positive epistemology, and those who interpret him as a skeptic or a mere pragmatist are mistaken. Instead he supports what he calls per- spectivism. This is a familiar take on Nietzsche, as perspectivism has been analyzed by many previous interpreters. The present paper presents a sketch of the textually best supported and logically most consistent treatment of perspectivism as a first- order epistemic theory. What’s original in the present paper is an argument that Nietzsche also offers a second-order methodological perspectivism aimed at enhancing understanding, an epistemic state distinct from knowledge. Just as Descartes considers and rejects radical skepticism while at the same time adopting methodological skepticism, one could consistently reject perspectivism as a theory of knowledge while accepting it as contributing to our understanding. It is argued that Nietzsche’s perspectivism is in fact two-tiered: knowledge is perspectival because truth itself is, and in addition there is a methodological perspectivism in which distinct ways of knowing are utilized to produce understanding. A review of the manner in which understanding is conceptualized in contemporary epistemology and philosophy of science serves to illuminate how Nietzsche was tackling these ideas

Conventional vs. tubeless percutaneous nephrolithotomy. Is the urinary diversion really necessary?

Introducción La nefrolitotomía percutánea (NLP) convencional utiliza derivación con nefrostomía para mejorar el drenaje de orina, facilitar la hemostasia postoperatoria y permitir un trayecto seguro para intervenciones adicionales futuras. Sin embargo, en los últimos años el procedimiento de NLP se ha modificado: ahora permite el retiro del uso del catéter de nefrostomía o de derivación urinaria, procedimiento conocido como tubeless. El presente estudio pretende evaluar la experiencia institucional en cuanto a seguridad, eficacia y ventajas de la NLP tubeless. Materiales y métodos Entre agosto de 2012 y mayo de 2014 se reclutó a 51 pacientes del Hospital Universitario San Ignacio y Clínica Fundadores para manejo con nefrolitotomía percutánea. Se incluyó a 49 pacientes con litiasis renal menor de 5cm de diámetro y mayor de 2cm con punción única o múltiple. Se aleatorizaron en 2 grupos: grupo A sin derivación (no nefrostomía no catéter doble J) 26 pacientes, grupo B con derivación (nefrostomía sonda Foley 18 Fr) 23 pacientes. Los desenlaces evaluados fueron: efectividad verificada mediante revisión de imágenes postoperatorias y definida como cálculo residual menor de 5mm, sangrado postoperatorio con medición de hemoglobina durante las primeras 24 h después de cirugía, valoración de dolor con escala visual análoga, necesidad de analgésicos durante las primeras 4 h, cantidad de rescates de analgésico durante las primeras 24 h de cirugía. Los datos se analizaron mediante el paquete estadístico IBM SPSS versión 20, utilizando estadística no paramétrica con la prueba de Wilcoxon Mann-Whitney una vez se determinó que la muestra no tenía una distribución normal. Las variables dicotómicas se analizaron utilizando la prueba de Chi2. Resultados Las características de base de los pacientes son comparables: la edad promedio en el grupo A fue de 44,73 años y en el B de 50,26 años (p=0,186), el peso en el grupo A fue de 75,96 kg y en el B de 71,96 kg (p=0,054), el tamaño de los cálculos en el A fue de 28,23mm en promedio y en el B de 29,69mm, sin diferencia estadísticamente significativa (p=0,517). No hubo diferencias significativas en cuanto a efectividad en ambos grupos: en el A el porcentaje de lito residual fue de 1,15% y en el B de 0,87% (p=0,713). No hubo diferencias estadísticamente significativas en cuanto a sangrado postoperatorio (p=0,566), pero sí se observó mayor dolor, requerimiento de analgésicos y mayor número de rescates en los pacientes a los cuales se les dejó derivación mediante nefrostomía. Discusión Nuestro trabajo demuestra que la NLP sin derivación urinaria es una técnica segura en aquellos pacientes en los cuales se logra una extracción completa del cálculo, con sangrado comparable a la cirugía convencional y, adicionalmente, con el beneficio de menor dolor y menor requerimiento de analgésico postoperatorio.Q4Artículo original5-9Introduction Conventional percutaneous nephrolithotomy (PNL) uses a nephrostomy derivation to improve the drainage of urine, facilitate postoperative hemostasis and allow a safe course for future additional surgical interventions. However, in recent years the PNL procedure has been modified to avoid the use of a nephrostomy catheter or any other urinary diversion. This procedure is known as tubeless. This study aims to assess the institutional experience in safety, efficiency and advantages of tubeless PNL. Materials and methods Between August 2012 and May 2014, 51 patients were recruited in San Ignacio University Hospital and Fundadores Clinic to be treated with PNL. Forty-nine patients with kidney lithiasis less than 5cm of diameter and greater than 2cm with single or multiple puncture were included. They were randomised into 2 groups: group A no derivation (no nephrostomy catheter, no double J) 26 patients, group B with derivation (18 Fr Foley nephrostomy catheter) 23 patients. The evaluated outcomes were: Effectiveness verified by reviewing postoperative images and defined as a residual stone less than 5mm of diameter, postoperative bleeding with hemoglobin measurement during the first 24h after surgery, pain assessment with the visual analog scale, need for analgesics during the first 4h, amount of analgesic rescues during the first 24h of surgery. Data were analyzed using the statistical package SPSS version 20, using the nonparametric statistical test Wilcoxon Mann-Whitney 11 it was determined that the sample does not have a normal distribution, the dichotomous variables were analyzed using Chi2 test. Results Baseline characteristics of patients are comparable: The average age in the group A was 44.73 and 50.26 years in the group B (P=.186), average weight in group A and B was 75.96kg and 71.96kg, respectively (P=.054), the average size of the stones in group A was 28.23mm and 29.69mm in group B with no statistically significant difference (P=.517). There were no significant differences in effectiveness in both groups, in group A the percentage of residual lithiasis was 1.15% and 0.87% in group B (P=.713). There were no statistically significant differences in postoperative bleeding (P=.566), although pain, analgesic requirement and number of rescues needed were greater in patients who were left with a nephrostomy derivation. Discussion Our work shows that percutaneous nephrolithotomy without urinary diversion is a safe procedure in patients in whom a complete stone removal is achieved, with bleeding comparable to conventional surgery, and additionally with the benefit of less pain and less postoperative analgesic requirement

Agronomic aspects, chemical composition and digestibility of forage from corn-crotalaria intercropping.

The objective of this study was to evaluate the effect of different intercropping and spacing arrangements of corn (Zea mays L) and crotalaria (Crotalaria spp) on the agronomic characteristics, chemical composition and forage digestibility. The experiment was distributed in a randomized complete block design with a 2 × 2 + 1 factorial scheme. The treatments were two cultivation systems (corn + Crotalaria juncea (CCJ) intercropping, and corn + Crotalaria ochroleuca (CCO) intercropping), in two spacing arrangements (A1 (corn and crotalaria sown in the same row) and A2 (corn and crotalaria sown in alternate rows)) plus control (single corn monocropping (CSC)), with six replicates per treatment, for 2 years. Forage plants were harvested when the corn grain reached the doughy-farinaceous phenological stage. Forage mass (total and of each species), morphological composition, chemical composition and in vitro digestibility were evaluated. The forage accumulation was higher for the A1 spatial arrangement. In the second year, the highest total forage mass was verified in the CCO inter- cropping (11 140 kg/ha). The highest corn mass (9402 kg/ha) was observed for CSC. The highest crotalaria mass was observed in the CCJ intercropping in both years. Regarding the chemical composition, CCJ and CCO intercropping had the highest crude protein concentra- tion. The lowest acid detergent fibre concentration was observed in CSC and CCO intercrop- ping, directly reflecting the in vitro dry matter digestibility coefficients. It is concluded that C. ochroleuca, sown between corn rows, had higher forage accumulation and nutritive value among the treatments tested in this experiment

Tamani grass-legume intercropping can improve productivity and composition of fodder destined to haylage or hay.

This research evaluated the biomass productivity and nutritional value of the haylage and hay from intercropping between Tamani grass and different legume species. For the productive characteristics of the different intercrops, we adopted a randomized block design, for evaluation of the combination of intercropping and conservation technic we used 5 x 2 factorial scheme (five intercrops and two types of conservation techniques). The treatments were Tamani grass as monoculture, and the intercrops of Tamani grass with crotalaria, soybean, cowpea, or pigeon pea. The conservation techniques were haylage (520 g/kg of DM) and hay (870 g/kg of DM). Plants were sown in alternate rows, with 45 cm of spacing between the rows. The parameters evaluated were grass and legume biomass production, canopy height, and haylage and hay chemical composition, and in vitro dry matter digestibility (ivDMD). There were no differences in the total biomass production between the intercrops and TA grass monoculture. The treatments intercropped with cowpea and soybean had the highest legume participation in the mixture, promoting an increase in crude protein and ivDMD content of haylage and hay. Haylage and hay had the same chemical composition, although haylage had higher ivDMD than hay. We concluded that intercropping Tamani grass with soybeans or cowpea maintained total biomass productivity and improved the nutritional value of haylage and ha

Latin America: the next region for haematopoietic transplant progress

Haematopoietic cell transplant activity in the 28 countries comprising Latin America is poorly defined. We conducted a voluntary survey of members of the Latin American Bone Marrow Transplantation Group regarding transplant activity 2009–2012. Collated responses were compared with data of transplant rates from the Worldwide Network for Blood and Marrow Transplantation for other geographic regions. Several socio-economic variables were analysed to determine correlations with transplant rates. In total, 94 teams from 12 countries reported 11519 transplants including 7033 autotransplants and 4486 allotransplants. Annual activity increased from 2517 transplants in 2009 to 3263 in 2012, a 30% increase. Median transplants rate (transplant per million inhabitants) in 2012 was 64 (autotransplants, median 40; allotransplants, median 24). This rate is substantially lower than that in North America and European regions (482 and 378) but higher than that in the Eastern Mediterranean and Asia Pacific regions (30 and 45). However, the Latin America transplant rate is 5–8-fold lower than that in America and Europe, suggesting a need to increase transplant availability. Transplant team density in Latin America (teams per million population; 1.8) is 3–4-fold lower than that in North America (6.2) or Europe (7.6). Within Latin America, there is substantial diversity in transplant rates by country partially explained by diverse socio-economic variables including per capita gross national income, health expenditure and physician density. These data should help inform future health-care policy in Latin America