Symbiotic potential and survival of native rhizobia kept on different carriers

Native rhizobia are ideal for use as commercial legume inoculants. The characteristics of the carrier used to store the inoculants are important for the survival and symbiotic potential of the rhizobia. The objective of this study was to investigate the effects of peat (PEAT), perlite sugarcane bagasse (PSB), carboxymethyl cellulose plus starch (CMCS), and yeast extract mannitol supplemented with mannitol (YEMM) on the survival, nodulation potential and N₂ fixation capacity of the native strains Sinorhizobium mexicanum ITTG R7^T and Rhizobium calliandrae LBP2-1^T and of the reference strain Rhizobium etli CFN42^T. A factorial design (4 × 3) with four repetitions was used to determine the symbiotic potential of the rhizobial strains. The survival of the strains was higher for PEAT (46% for strain LBP2-1^T, 167% for strain CFN42^T and 219% for strain ITTG R7^T) than for the other carriers after 240 days, except for CFN42^T kept on CMCS (225%). All the strains kept on the different carriers effectively nodulated common bean, with the lowest number of nodules found (5 nodules) when CFN42^T was kept on CMCS and with the highest number of nodules found (28 nodules) when ITTG R7^T was kept on PSB. The nitrogenase activity was the highest for ITTG R7^T kept on PEAT (4911 μmol C₂H₄ per fresh weight nodule h⁻¹); however, no activity was found when the strains were kept on YEMM. Thus, the survival and symbiotic potential of the rhizobia depended on the carrier used to store them.

Shock séptico en unidad de cuidados intensivos: Enfoque actual en el tratamiento / Septic shock in intensive care units: Current focus on treatment

Los pilares terapéuticos del niño con shock séptico se mantienen en el tiempo, sin embargo, se han incorporado nuevos conceptos, siendo importante que el pediatra y el intensivista tengan conocimiento a cabalidad de ellos. La reanimación con fluidos es una intervención fundamental, no obstante, aún no se ha establecido un tipo de fluido ideal, presentando cada uno limitaciones específicas, no existiendo evidencia sobre la superioridad de un tipo de fluido. Si a pesar de una adecuada resucitación con fluidos persiste el shock, el inicio de inótropos y/o vasopresores está indicado. En caso de refractariedad al uso de vasopresores, nuevos fármacos vasoactivos pueden ser empleados y el uso de hidrocortisona debe considerarse en niños con sospecha de insuficiencia suprarrenal. Existe controversia respecto a la transfusión de glóbulos rojos o el nivel óptimo de glucemia, no existiendo consenso en el valor umbral para el uso de estos hemocomponentes o el inicio de insulina, respectivamente. Asimismo, la utilización de la hemofiltración de alto volumen (HFAV)aún permanece controversial, requiriendo mayores estudios para su recomendación en forma rutinaria en el curso de un shock séptico refractario. El soporte nutricional es primordial, ya que la desnutrición es una grave complicación que debe ser prevenida y tratada adecuadamente. El objetivo de la presente revisión es entregar una actualización en los más recientes avances en tratamiento del shock séptico en la población pediátrica.

Essential therapeutic principles in children with septic shock persist over time, although some new concepts have been recently incorporated, and fully awareness of pediatricians and intensivists is essential. Fluid resuscitation is a fundamental intervention, but the kind of ideal fluid has not been established yet, as each of these interventions has specific limitations and there is no evidence supportive of the superiority of one type of fluid. Should septic shock persists despite adequate fluid resuscitation, the use of inotropic medication and/or vasopressors is indicated. New vasoactive drugs can be used in refractory septic shock caused by vasopressors, and the use of hydrocortisone should be considered in children with suspected adrenal insufficiency, as it reduces the need for vasopressors. The indications for red blood cells transfusion or the optimal level of glycemia are still controversial, with no consensus on the threshold value for the use of these blood products or the initiation of insulin administration, respectively. Likewise, the use of high-volume hemofiltration is a controversial issue and further study is needed on the routine recommendation in the course of septic shock. Nutritional support is crucial, as malnutrition is a serious complication that should be properly prevented and treated. The aim of this paper is to provide update on the most recent advances as concerns the treatment of septic shock in the pediatric population.

Performance equivalence study of sodium starch glycolate, modified maize starch and maize starch as disintegrants in paracetamol tablet formulation

Fierce price competition informed the reappraisal and reformulation of paracetamol tablet. Sodium starch glycolate [SSG] was implicated in the high cost and needed to be replaced. The use of modified maize starch [MMS] produced by cold, dilute acid hydrolysis of maize starch [MS] offered good and cheaper alternative. Evaluation of different disintegrants using 5 batch formulations coded SSG-3, MS-3, MMS-3, MMS-6 and MMS-9 and characterization of resultant tablets showed that interchanging SSG with MMS resulted in no deleterious therapeutic consequences. Inclusion of 6% MMS in the paracetamol formulation gave tablets that exhibited good mechanical and dissolution properties comparable to the tablets produced with 3% sodium starch glycolate. Indeed, at 95% confidence level, t-test which compares the p-value [?0.05] of dissolution of the batch formulations returned values of 0.000056 for MS-3, 0.0182 for MMS-3, 0.0965 for MMS-6 and 0.1433 for MMS-9. The values confirmed the significant differences between batch SSG-3 and batches MS-3 and MMS-3 and no difference of any significance in batches MMS-6 and MMS-9. Hence MS and MMS at 3% level can not effectively replace SSG at 3% level. The poor friability [1.12%] as well as higher disintegration time [16 minutes, 54 seconds], both higher than official limits of<1% and ?15 minutes respectively, would not also allow the use of MMS at 3 and 9% level as substitutes for 3% SSG. Thus, only MMS at 6% inclusion level can interchange with SSG 3%. Cost-benefit analysis showed that over 9% cost reduction is achieved by the replacement without compromising both physical and chemical qualities of the resultant tablets which include mean dissolution time [MDT] 50% of 4.5 minutes and dissolution of 103.87% in 30 minutes

Genetic variability for waxy genes in Argentinean bread wheat germplasm

Amylose and amylopectin are the two polysaccharides that constitute starch in bread wheat and the enzyme GBSSI (Granule-bound starch synthase I), also known as waxy protein, is responsible for amylose synthesis in storage tissues. Decrease of the amylose content in starch has been associated with the lack of waxy protein(s). In this work, different sets of PCR markers were used to characterize the genetic variability of waxy loci from 103 Argentinean bread wheat cultivars. For the Wx-A1 locus, Wx-A1a and a novel molecular allele designed Wx-A1g were detected. Wx-B1 locus showed three alleles (Wx-B1a, Wx-B1b, Wx-B1e), and Wx-D1 locus showed only the Wx-D1a allele. Novel single-locus allele specific markers for Wx-A1b, Wx-B1b and Wx-D1b null alleles were also described. To our best knowledge this is the first study focused to characterize the genetic variability for waxy genes in bread wheat cultivars from South America.

Evaluación de la digestibilidad in vitro de un sustituto lácteo fabricado con harinas no precocidas / In vitro digestibility of a milk substitute fabricated with uncooked flours

Los sustitutos lácteos son utilizados en el desayuno de los beneficiarios del Programa de alimentación Escolar de la Junta Nacional de Auxilio Escolar y Becas en Chile. Los ingredientes principales de los sustitutos lácteos son leche, azúcar y harinas de cereales y las bases técnicas para fabricar estos productos estipulan además de sus proporciones que las harinas utilizadas deben estar precocidas lo que se evalúa determinando el grado de generalización de los almidones en cual debe ser mínimo de 92 por ciento. En la actualidad se ha presentado al Programa un nuevo tipo de sustituto lácteo de menor costo, formulado con harinas no precocidas y que contiene un preparado enzimático asegurándose por parte del fabricante que bajo las condiciones de reconstitución por él indicadas (85ºC y 5 min de reposo) se lograría la precocción de las harinas. El objetivo del presenta trabajo fue evaluar la digestibilidad in vitro, el efecto del preparado enzimático incorporado (tamaño molecular de almidón y equivalente de dextrosa) y el grado de gelatinización en este producto (SLE) reconstituído bajo diferentes temperaturas y tiempos de reposo. Como testigo se utilizó el mismo sustituto lácteo pero sin la incorporación del preparado enzimatico. A 85ºC y 5 min. de reposo DV para SLE fue 93,8 por ciento. a temperaturas <85ºC y 5 min, DV disminuyó significativamente (p>0,05) a 85 por ciento (75ºC), 82,2 por ciento (50ºC), 33,0 por ciento (40ºC) y 41,4 por ciento (20ºC). DV aumentó significativamente al aumentar el tiempo de reposo a 30 min. sólo para temperaturas >60ºC. Se observó que 85ºC/min el presente enzimático ha alcanzado un 92,1 por ciento de su capacidad hidrolítica potencial. El grado de gelatinización (GG) de SLE varió entre 42,6 por ciento (40ºC) y 93,8 por ciento (85ºC) para 5 min. de reposo, valores que aumentaron al dejar reposar por 30 minutos. El producto testigo mostró valores similares de DV y GG a SLE para todas las condiciones evaluadas. Se concluye que tanto SLE como el testigo presentan una buena digestibilidad in vitro y grado de gelatinización al reconstruir a 85ºC/5 min. Estos resultados indicarían que no es necesario precocer las harinas si se utilizan condiciones de preparación como las señaladas y que la incorporación de enzima cumpliría el objetivo de mejorar características físico químicas como la viscosidad del producto preparado