Rápido método de selección de plantas resistentes a herbicidas

Rápido método de selección de plantas resistentes a herbicidasFil: Larran, A. S. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentin

Nota Corta: Endophytic fungi in healthy soybean leaves

SUMMARY Fungal endophytes were isolated from healthy cultivated soybean leaves at two growth stages (R2-R3 and R4-R5) during the growing season 1997/98. Samples were obtained from a segregating population (F 3 generation) cultivated at the experimental field of the Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, Buenos Aires, Argentina. Twelve genera of endophytic fungi were isolated and identified. In general, in both growth stages the same species were isolated and most of them did not show significant differences in their infection frequencies. Most of the fungi isolated are cited as soybean pathogens in different places of the world. The most commonly isolated endophytes included Alternaria alternata and Glomerella cingulata (= Colletotrichum gloeosporioides). Key words: endophytes, Glycine max Endophytes are fungi that form inapparent infections within leaves and stems of healthy plant

Secretomas fúngicos como pretratamiento biológico sobre biomasa lignocelulósica de panicum prionitis

Debido a la inminente necesidad de producir y utilizar fuentes de energía renovables, ciertos pastizales naturales como Panicum prionitis, ricos en polisacáridos y con baja eficiencia forrajera, representan una fuente de azúcares fermentables muy interesante para la producción de bioetanol de segunda generación. Sin embargo, la presencia de lignina en sus hojas hace que el proceso de producción requiera de un pretratamiento previo a la sacarificación. Los hongos de la podredumbre blanca de la madera son capaces de degradar los materiales lignocelulósicos, secretando al medio extracelular diversas enzimas involucradas en tal proceso. En base a este criterio, se evaluó la eficiencia de los secretomas de dos especies fúngicas (Pycnoporus sanguineus y Ganoderma applanatum) como agentes de pretratamiento sobre la biomasa de P. prionitis. Los resultados demuestran que el pretratamiento con secretomas fúngicos resulta más eficiente que los tradicionales (pretratamiento químico y con enzimas ligninolíticas comerciales), permitiendo hidrolizar hasta un 47,5% de la celulosa en el caso de G. applanatum. Ensayos de cromatografía líquida acoplada a espectrometría de masas permitieron la identificación de una gran cantidad de proteínas en los secretomas, revelando que el 34% y el 42% de ellas se encuentran involucradas en los procesos de degradación de la biomasa lignocelulósica para G. applanatum y P. sanguineus, respectivamenteFil: Gauna, Albertina . Universidad Nacional de RosarioFil: Feldman, Susana R.. Universidad Nacional de RosarioFil: Larran, Alvaro S.. Universidad Nacional de RosarioFil: Permingeat, Hugo R.. Universidad Nacional de RosarioFil: Perotti, Valeria E.. Universidad Nacional de Rosari

Stepwise Optimization of the Procedure for Assessment of Circulating Progenitor Cells in Patients with Myocardial Infarction

The number and functional activity of circulating progenitor cells (CPCs) is altered in diabetic patients. Furthermore, reduced CPC count has been shown to independently predict cardiovascular events. Validation of CPCs as a biomarker for cardiovascular risk stratification requires rigorous methodology. Before a standard operation protocol (SOP) can be designed for such a trial, a variety of technical issues have to be addressed fundamentally, which include the appropriate type of red blood cell lysis buffer, FMO or isotype controls to identify rare cell populations from background noise, optimal antibody dilutions and conditions of sample storage. We herein propose improvements in critical steps of CPC isolation, antigenic characterization and determination of functional competence for final application in a prospective investigation of CPCs as a biomarker of outcome following acute myocardial infarction.In this validation study, we refined the standard operating procedure (SOP) for flow cytometry characterisation and functional analysis of CPCs from the first 18 patients of the Progenitor Cell Response after Myocardial Infarction Study (ProMIS). ProMIS aims to verify the prognostic value of CPCs in patients with either ST elevation or non-ST elevation myocardial infarction with or without diabetes mellitus, using cardiac magnetic resonance imaging (MRI) for assessment of ventricular function as a primary endpoint. Results indicate crucial steps for SOP implementation, namely timely cell isolation after sampling, use of appropriate lysis buffer to separate blood cell types and minimize the acquisition events during flow cytometry, adoption of proper fluorophore combination and antibody titration for multiple antigenic detection and introduction of counting beads for precise quantification of functional CPC activity in migration assay.With systematic specification of factors influencing the enumeration of CPC by flow cytometry, the abundance and migration capacity of CPCs can be correctly assessed. Adoption of validated SOP is essential for refined comparison of patients with different comorbidities in the analysis of risk stratification

Safety perspectives on presently considered drugs for the treatment of COVID‐19

Intense efforts are underway to evaluate potential therapeutic agents for the treatment of COVID‐19. In order to respond quickly to the crisis, the repurposing of existing drugs is the primary pharmacological strategy. Despite the urgent clinical need for these therapies, it is imperative to consider potential safety issues. This is important due to the harm–benefit ratios that may be encountered when treating COVID‐19, which can depend on the stage of the disease, when therapy is administered and underlying clinical factors in individual patients. Treatments are currently being trialled for a range of scenarios from prophylaxis (where benefit must greatly exceed risk) to severe life‐threatening disease (where a degree of potential risk may be tolerated if it is exceeded by the potential benefit). In this perspective, we have reviewed some of the most widely researched repurposed agents in order to identify potential safety considerations using existing information in the context of COVID‐19

Epicoccum nigrum P16, a Sugarcane Endophyte, Produces Antifungal Compounds and Induces Root Growth

Background: Sugarcane is one of the most important crops in Brazil, mainly because of its use in biofuel production. Recent studies have sought to determine the role of sugarcane endophytic microbial diversity in microorganism-plant interactions, and their biotechnological potential. Epicoccum nigrum is an important sugarcane endophytic fungus that has been associated with the biological control of phytopathogens, and the production of secondary metabolites. In spite of several studies carried out to define the better conditions to use E. nigrum in different crops, little is known about the establishment of an endophytic interaction, and its potential effects on plant physiology. Methodology/Principal Findings: We report an approach based on inoculation followed by re-isolation, molecular monitoring, microscopic analysis, plant growth responses to fungal colonization, and antimicrobial activity tests to study the basic aspects of the E. nigrum endophytic interaction with sugarcane, and the effects of colonization on plant physiology. The results indicate that E. nigrum was capable of increasing the root system biomass and producing compounds that inhibit the in vitro growth of sugarcane pathogens Fusarium verticillioides, Colletotrichum falcatum, Ceratocystis paradoxa, and Xanthomomas albilineans. In addition, E. nigrum preferentially colonizes the sugarcane surface and, occasionally, the endophytic environment. Conclusions/Significance: Our work demonstrates that E. nigrum has great potential for sugarcane crop application because it is capable of increasing the root system biomass and controlling pathogens. The study of the basic aspects of the interaction of E. nigrum with sugarcane demonstrated the facultative endophytism of E. nigrum and its preference for the phylloplane environment, which should be considered in future studies of biocontrol using this species. In addition, this work contributes to the knowledge of the interaction of this ubiquitous endophyte with the host plant, and also to a better use of microbial endophytes in agriculture.State of Sao Paulo Research Foundation (FAPESP)FAPESP (State of Sao Paulo Research Foundation) [02/14143-3, 10/08286-2]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq