Virus-mediated transient expression techniques enable gene function studies in black-grass

Even though considerable progress has been made in weed ecology, weed molecular biology has been hindered by an inability to genetically manipulate weeds. Genetic manipulation is essential to demonstrate a causative relationship between genotype and phenotype. Herein we demonstrate that virus-mediated transient expression techniques developed for other monocots can be used in black-grass (Alopecurus myosuroides) for loss- and gain-of-function studies. We not only use virus induced gene silencing (VIGS) to create the black-grass exhibiting reduced PHYTOENE DESATURASE expression and virus-mediated overexpression (VOX) to drive GREEN FLUORESCENT PROTEIN, we demonstrate these techniques are applicable to testing hypotheses related to herbicide resistance in black-grass. We use VIGS to demonstrate that AmGSTF1 is necessary for the resistant biotype Peldon to survive fenoxaprop application and show the heterologous expression of the bialaphos resistance gene with VOX is sufficient to confer resistance to an otherwise lethal dose of glufosinate. Black-grass is the most problematic weed for winter-cereal farmers in the UK and Western Europe as it has rapidly evolved adaptions that allow it to effectively avoid current integrated weed management practices. Black-grass also reduces yields and therefore directly threatens food security and productivity. Novel disruptive technologies which mitigate resistance evolution and enable better control over this pernicious weed are therefore required. These virus-mediated protocols offer a step change in our ability to alter genes of interest under controlled laboratory conditions and therefore to gain a molecular-level understanding of how black-grass can survive in the agri-environment

Computer vision-based analytical chemistry applied to determining iron in commercial pharmaceutical formulations

[EN] Two different computer vision-based analytical chemistry (CVAC) methods were developed to quantify iron in the commercial pharmaceutical formulations Ferbisol (R) and Ferro sanol (R). The methods involve using a digital camera or a desktop scanner to capture a digital image of a series of Fe2+ standard solutions and the unknown sample upon reaction with o-phenanthroline. The images are processed with appropriate software (e.g., the public domain programme ImageJ, from NIH) to obtain a numerical value (analytical signal) based on colour intensity. The fact that such a value is proportional to the analyte concentration allows one to construct a calibration graph from the standards and interpolate the value for the sample in order to determine its concentration. The results thus obtained were compared with those provided by a spectrophotometric method and the US Pharmacopoeia's recommended method. The differences never exceeded 2%. The two proposed methods are simple and inexpensive; also, they provide an effective instrumental alternative to spectrophotometric methods which can be especially beneficial in those cases where purchasing and maintaining a spectrophotometer is unaffordable.Solana-Altabella, A.; Sanchez-Iranzo, M.; Bueso-Bordils, J.; Lahuerta-Zamora, L.; Mellado Romero, AM. (2018). Computer vision-based analytical chemistry applied to determining iron in commercial pharmaceutical formulations. Talanta. 188:349-355. https://doi.org/10.1016/j.talanta.2018.06.008S34935518

Charting the evolutionary path of the SUMO modification system in plants reveals molecular hardwiring of development to stress adaptation

SUMO modification is part of the spectrum of Ubiquitin-like (UBL) systems that give rise to proteoform complexity through post-translational modifications (PTMs). Proteoforms are essential modifiers of cell signaling for plant adaptation to changing environments. Exploration of the evolutionary emergence of Ubiquitin-like (UBL) systems unveils their origin from prokaryotes where it is linked to the mechanisms that enable sulfur uptake into biomolecules. We explore the emergence of the SUMO machinery across the plant lineage from single-cell to land plants. We reveal the evolutionary point at which plants acquired the ability to form SUMO chains through the emergence of SUMO E4 ligases hinting at its role in facilitating multicellularity. Additionally, we explore the possible mechanism for the neofunctionalization of SUMO proteases through the fusion of conserved catalytic domains with divergent sequences. We highlight the pivotal role of SUMO proteases in plant development and adaptation, offering new insights into target specificity mechanisms of SUMO modification during plant evolution. Correlating the emergence of adaptive traits in the plant lineage with established experimental evidence for SUMO in developmental processes we propose that SUMO modification has evolved to link developmental processes to adaptive functions in land plants

Mathematical model to predict the dry matter intake of dairy cows on pasture

In pasture-based dairy systems, there is a close relationship between milk production and dry matter intake (DMI), hence the importance of measuring these variables, although obtaining this information implies high labour and costs. The objective of this study was to design a mathematical model to predict DMI for grazing dairy cows. This model was based on the basic principle of the fill-unit system. In this scheme, cows and feedstuffs were described in terms of feed intake capacity (FIC) and fill (unit/amount of feed), respectively. The FIC was determined by the animal’s ability to regulate feed intake which depends on factors such as body size, age and lactation status. The “fill” was determined by the nutritional properties of the feedstuff such as its dry matter (DM) digestibility and crude protein (CP) content, among others. In the design of the model, ad lib. feed consumption was assumed. Parity, state of lactation and gestation were considered to estimate the cow ingestion capacity. Satiety values (SV) were determined for Festuca arundinacea and Lolium multiflorum and these values were incorporated into the model, including DM, CP, neutral detergent fibre (NDF) and in vitro digestible organic matter (dOM). The fixed parameters of the model were determined by adjusting a polynomial regression to the data from three experiments with lactating Holstein cows from Baja California, Mexico (n=30).The model allows predicting DMI, using as inputs, easily measured data and does not require knowing daily milk yield (MY) or body weight (BW), so the model is practical and consistent. The results obtained from the model were satisfactory because they were similar to those attained experimentally. Average DMI was 21.68 kg/d in one group and 23.44 kg/d in the other; when applying the model, we obtained an estimate of 22.82 kg/d for a cow with characteristics similar to those of the cows under stud

Broadly Protective Shigella Vaccine Based on Type III Secretion Apparatus Proteins

Shigella spp. are food- and waterborne pathogens that cause severe diarrheal and dysenteric disease associated with high morbidity and mortality. Individuals most often affected are children under 5 years of age in the developing world. The existence of multiple Shigella serotypes and the heterogenic distribution of pathogenic strains, as well as emerging antibiotic resistance, require the development of a broadly protective vaccine. All Shigella spp. utilize a type III secretion system (TTSS) to initiate infection. The type III secretion apparatus (TTSA) is the molecular needle and syringe that form the energized conduit between the bacterial cytoplasm and the host cell to transport effector proteins that manipulate cellular processes to benefit the pathogen. IpaB and IpaD form a tip complex atop the TTSA needle and are required for pathogenesis. Because they are common to all virulent Shigella spp., they are ideal candidate antigens for a subunit-based, broad-spectrum vaccine. We examined the immunogenicity and protective efficacy of IpaB and IpaD, alone or combined, coadministered with a double mutant heat-labile toxin (dmLT) from Escherichia coli, used as a mucosal adjuvant, in a mouse model of intranasal immunization and pulmonary challenge. Robust systemic and mucosal antibody- and T cell-mediated immunities were induced against both proteins, particularly IpaB. Mice immunized in the presence of dmLT with IpaB alone or IpaB combined with IpaD were fully protected against lethal pulmonary infection with Shigella flexneri and Shigella sonnei. We provide the first demonstration that the Shigella TTSAs IpaB and IpaD are promising antigens for the development of a cross-protective Shigella vaccine

Methodological approach for the analysis of risks due to hazardous atmospheres in the surrounding areas to industrial facilities which handling HAZMAT

La ausencia de proyectos de ordenamiento territorial, expone a la población a potenciales accidentes tecnológicos. Su impacto potencial puede ser evaluado mediante la estimación del riesgo. Se propone entonces una metodología para estimar el riesgo por amenazas tecnológicas enfocada en dos componentes: el procesamiento de datos meteorológicos para la definición de escenariosmás probables y más conservadores; y la aplicación de un índice de vulnerabilidad social para clasificar la población. Como caso de estudio se simuló la emisión de un tanque recibidor de amoníaco licuado en una industria frigorífica (La Plata, Argentina) y se estimó el riesgo considerando las características sociodemográficas de la población. Los resultados muestran las áreas donde se concentran los individuos en riesgo, posibles de ser atendidas para la etapa de prevención. Como ventaja, este enfoque metodológico sistémico resulta flexible, ya que brinda la posibilidad de ser aplicado en diversos escenarios, en función de la información local asequible.The absence of territorial planning projects exposes the population to potential technological incidents. Its potential impact can be assessed by risk estimation. Taking this into account, the potential condition can be warned. In this work we propose a methodology to estimate risk of technological hazards, focused on two components: the processing of meteorological databases to define the most probably and conservative scenario, and the application of a local social vulnerability index to classify the population. In this case of study, the risk was estimated for a hypothetical release of liquefied ammonia in a meat-packing industry (La Plata, Argentina). The results show the areas associated with higher risks, which are worth being addressed for the prevention of disasters in the region. Advantageously, this systemic approach is methodologically flexible as it provides the possibility of being applied in various scenarios based on the available information of both, the exposed population and its meteorology.Centro de Investigaciones del Medioambient

Aplicación de tecnologías de Sistemas de Información Geográfica (SIG) para la estimación del riesgo por exposición a compuestos orgánicos volátiles (COVs)

En este trabajo se expone una metodología para estimar el riesgo que generan los COVs en la salud de la población más vulnerable de la región del Gran La Plata. Se propone utilizar un Sistema de Información Geográfica (SIG) para el análisis espacial ya que permite el abordaje mediante capas temáticas, facilitando el procesamiento de la información. La vulnerabilidad se evaluó mediante la construcción de un Puntaje de Clasificación Espacial Porcentual con las variables de costo “Hogares con Necesidades Básicas Insatisfechas” y “Hogares calefaccionados por combustión de biomasa”. La concentración de inmisión de benceno y BTEX se determinó mediante interpolación de medidas efectuadas con muestreadores pasivos en primavera de 2008 e invierno de 2009. La población afectada se estableció mediante el cruce de estas variables, generando cartografías donde se visualizan las áreas de riesgo de padecer cáncer discriminadas por su vulnerabilidad.Facultad de Ciencias Exacta

Estimación de la distribución de fuentes de emisión de dióxido de azufre en la ciudad de Bahía Blanca

Una adecuada gestión del medio ambiente requiere de la complementación de metodologías que permitan no sólo caracterizar la calidad del aire y conocer sus efectos en la salud, sino también reconocer las principales fuentes de emisión de los contaminantes de interés y sus contribuciones, de manera de poder definir una estrategia que permita conciliar los procesos productivos con la salud de la población. En este trabajo se implementa el modelo NTA (Nonparametric Trajectory Analysis) en el software libre Python, para estimar la distribución de fuentes de emisión y la concentración promedio del dióxido de azufre en la ciudad de Bahía Blanca (Provincia de Buenos Aires, Argentina). La herramienta es considerada un híbrido de los modelos receptores, dado que utiliza mediciones tomadas en el centro de monitoreo y datos meteorológicos locales. Para tal objetivo, se hace uso de la información de calidad de aire de dióxido de azufre, de acceso libre y gratuito en el sitio web del municipio, junto con datos del Servicio Meteorológico Nacional (SMN), descritos en el mismo período temporal. En función de la información recopilada, se aplica la herramienta a distintos períodos temporales, complementando el estudio con la elaboración de la rosa de los vientos para el mismo periodo de interés. Esta herramienta permitió conocer con más detalle el comportamiento previsto del patrón direccional del contaminante, a partir de la estimación de la zona de mayor de distribución de fuentes. Particularmente, se evidenciaron altas concentraciones al noroeste de la estación de monitoreo, en mayor medida para los meses fríos del año. Si bien Petrobras Argentina S.A. representa solo el 17.2% anual de las emisiones de SO2, es destacable la relevancia que tienen los vientos predominantes en la dispersión de los contaminantes, y consecuente en la definición de las áreas de impacto. Como fortaleza de la herramienta, se destaca la posibilidad de proyectar zonas de mayor amenaza en función de la meteorología local, de modo de optimizar los recursos disponibles aplicados a campañas de monitoreo, al acotar la potencial región de emisión.Centro de Investigaciones del MedioambienteCentro de Investigación y Desarrollo en Ciencias Aplicada

Characterization of BTEX emission sources in the Greater La Plata urban conglomerate using receptor models

Estudios previos en la región identifican a la industria petroquímica y al tráfico como las principales fuentes de emisión de BTEX. Para profundizar estos estudios, se aplicaron diferentes herramientas para caracterizar las fuentes emisoras. El Análisis de Componentes Principales (PCA) fue utilizado para cuantificar las fuentes de BTEX y los Métodos No Paramétricos para estimar la concentración en el espacio. Uno de estos, Nonparametric Wind Regression (NWR) es usado para obtener la relación entre la concentración y las componentes del viento. Su complemento, Source Apportionment (SA), relaciona las mayores contribuciones en función de las direcciones. A continuación, Nonparametric Trajectory Analysis (NTA) fue usado para estimar la concentración de BTEX en una coordenada geográfica. El resultado permitió describir las características de cada área dentro de la región: zonas residenciales y urbanas evidencian predominancia de una única fuente, presumiblemente asociada con el tráfico, mientras que la zona industrial presenta la contribución de dos fuentes principales, presumiblemente la industria petroquímica y el tráfico.Previous studies in the region identify the petrochemical industry and traffic as the main sources of BTEX emission. In order to further these studies, different tools were applied to characterize the emission sources. Principal Components Analysis (PCA) was used to quantify BTEX sources and Nonparametric Methods to estimate the concentration in the space. One of them, Nonparametric Wind Regression (NWR) was used to obtain the relationship between concentration and the wind components. Its complement, Source Apportionment (SA), relates higher contributions as a function of the directions. Afterwards, Nonparametric Trajectory Analysis (NTA) was used to estimate the concentration of BTEX on a geographical coordinate. The result allowed describing characteristics of each area inside the region: residential and urban zones evidence predominance of a single source, presumably associated with traffic, while industrial zone presents the contribution of two main sources, presumably petrochemical industry and traffic.Centro de Investigaciones del Medioambient