Oak root response to ectomycorrhizal symbiosis establishment: RNA-Seq derived transcript identification and expression profiling

Ectomycorrhizal symbiosis is essential for the life and health of trees in temperate and boreal forests where it plays a major role in nutrient cycling and in functioning of the forest ecosystem. Trees with ectomycorrhizal root tips are more tolerant to environmental stresses, such as drought, and biotic stresses such as root pathogens. Detailed information on these molecular processes is essential for the understanding of symbiotic tissue development in order to optimize the benefits of this natural phenomenon. Next generation sequencing tools allow the analysis of non model ectomycorrhizal plant-fungal interactions that can contribute to find the "symbiosis toolkits" and better define the role of each partner in the mutualistic interaction. By using 454 pyrosequencing we compared ectomycorrhizal cork oak roots with non-symbiotic roots. From the two cDNA libraries sequenced, over 2 million reads were obtained that generated 19,552 cork oak root unique transcripts. A total of 2238 transcripts were found to be differentially expressed when ECM roots were compared with non-symbiotic roots. Identification of up- and down-regulated gens in ectomycorrhizal roots lead to a number of insights into the molecular mechanisms governing this important symbiosis. In cork oak roots, ectomycorrhizal colonization resulted in extensive cell wall remodelling, activation of the secretory pathway, alterations in flavonoid biosynthesis, and expression of genes involved in the recognition of fungal effectors. In addition, we identified genes with putative roles in symbiotic processes such as nutrient exchange with the fungal partner, lateral root formation or root hair decay. These findings provide a global overview of the transcriptome of an ectomycorrhizal host root, and constitute a foundation for future studies on the molecular events controlling this important symbiosis.This work was funded by the Portuguese Foundation for Science and Technology (www.fct.pt) in the frame of the project Cork Oak EST Consortium SOBREIRO/0034/2009. Post-doc grant to MS was supported by the Portuguese Foundation for Science and Technology (SFRH/BPD/25661/2005). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Antimicrobial Consumption in Latin American Countries: First Steps of a Long Road Ahead

Background: Irrational antimicrobial consumption (AMC) became one of the main global health problems in recent decades. Objective: In order to understand AMC in Latin-American Region, we performed the present research in 6 countries. Methods: Antimicrobial consumption (J01, A07A, P01AB groups) was registered in Argentina, Chile, Colombia, Costa Rica, Paraguay, and Peru. Source of information, AMC type, DDD (Defined Daily Doses), DID (DDD/1000 inhabitants/day), population were variables explored. Data was analyzed using the Global Antimicrobial Resistance and Use Surveillance System (GLASS) tool. Results: Source of information included data from global, public, and private sectors. Total AMC was highly variable (range 1.91-36.26 DID). Penicillin was the most consumed group in all countries except in Paraguay, while macrolides and lincosamides were ranked second. In terms of type of AMC according to the WHO-AWaRe classification, it was found that for certain groups like “Reserve,” there are similarities among all countries. Conclusion and Relevance: This paper shows the progress that 6 Latin-American countries made toward AMC surveillance. The study provides a standardized approach for building a national surveillance system for AMC data analysis. These steps will contribute to the inclusion of Latin-America among the regions of the world that have periodic, regular, and quality data of AMC.Facultad de Ciencias Médica

Modulatory effects of arginine, glutamine and branched-chain amino acids on heat shock proteins, immunity and antioxidant response in exercised rats

Heat shock proteins (HSPs) are endogenous proteins whose function is to maintain the cell's tolerance to insult, and glutamine supplementation is known to increase HSP expression during intense exercise. Since few studies have addressed the possibility that supplementation with other amino acids could have similar effects to that of glutamine, our objective was to evaluate the effects of leucine, valine, isoleucine and arginine as potential stimulators of HSPs 25, 60, 70 and 90 in rats subjected to acute exercise as a stressing factor. The immune markers, antioxidant system, blood parameters, glycogen and amino acid profile responses were also assessed. Male Wistar rats were divided into seven groups: control (rest, without gavage), vehicle (water), L-leucine, L-isoleucine, L-valine, L-arginine and L-glutamine. Except for the control, all animals were exercised and received every amino acid by oral gavage. Arginine supplementation up-regulated muscle HSP70 and HSP90 and serum HSP70, however, none of the amino acids affected the HSP25. All amino acids increased exercise-induced HSP60 expression, except for valine. Antioxidant enzymes were reduced by exercise, but both glutamine and arginine restored glutathione peroxidase, while isoleucine and valine restored superoxide dismutase. Exercise reduced monocyte, platelet, lymphocyte and erythrocyte levels, while leucine stimulated immune response, preserved the levels of the lymphocytes and increased leukocytes and maintained platelets at control levels. Plasma and muscle amino acid profiles showed specific metabolic features. The data suggest that the tissue-protecting effects of arginine could proceed by enhancing specific HSPs in the bod8932283238FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2013/02862-0; 2013/06494-5; 2016/06630-

Breakup of gas bubbles rising in molten metals

A theory on the breakup of rising bubbles is developed on the basis of long-term experiments with bubbles rising in different liquids. The probability of bubble breakup is expressed in terms of half-life as a dimensionless function of the bubble volume and liquid properties. The results are applied to develop a mathematical model of bubbles rising in a column of high density liquid under a low external pressure. The model predicts that in typical steelmaking equipment the size of bubbles approaching the liquid level depends mostly on the external pressure and it is quite independent of the original size of the bubbles

Apoptosis and necrosis: two distinct events induced by cadmium in cortical neurons in culture

1. Cadmium is an extremely toxic metal commonly found in industrial workplaces, a food contaminant and a major component of cigarette smoke. Cadmium can severely damage several organs, including the brain. In this work, we have studied both the cadmium toxicity on rat cortical neurons in culture and the possible protective effect of serum. 2. Our results indicate that: (1) cadmium is taken up by the neurons in a dose and serum dependent way; (2) cadmium, at concentrations from 1 μM or 10 μM (depending on the absence or the presence of serum) up to 100 μM, decreases the metabolic capacity, which was evaluated by the XTT (tetrazolium salt) test; (3) cadmium induces apoptosis and LDH (lactate dehydrogenase) release in a dose dependent way; (4) in a serum-free medium, the cadmium-induced apoptosis is accompanied by caspase-3 activation; (5) both the caspase-3 activation and the cadmium-induced apoptosis are reversed by N-acethyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO), a selective caspase-3 inhibitor, indicating that the caspase-3 pathway is involved in cadmium-induced apoptosis in cortical neurons; and (6) the cadmium concentrations which produce caspase-3 activation do not modify the intracellular ATP levels; however, higher cadmium concentrations lead to both intracellular ATP depletion and ATP release, but do not increase the caspase-3 activity, indicating that cadmium also produces cellular death by necrosis. 3. These results suggest that cadmium induces either apoptosis or necrosis in rat cortical neurons, depending on the cadmium concentration