Multi-class phytohormone analysis in rice cultivars using liquid chromatography high-resolution Orbitrap mass spectrometry operating in different scan modes

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Trace analysis of multi-class phytohormones in Oryza sativa using different scan modes in high-resolution Orbitrap mass spectrometry : method validation, concentration levels, and screening in multiple accessions

Phytohormones are signaling and regulating metabolites involved in numerous plant processes, including growth, development, and responses to stress. Currently, the focus is on the analysis of multiple phytohormones in order to characterize crosstalk and hormone signaling networks. In this paper, representative phytohormones of the major classes are simultaneously determined in rice tissues by a generic solid-liquid extraction, followed by liquid chromatography and electrospray ionization high-resolution tandem mass spectrometry using a Q-Exactive (TM) instrument. After a thorough optimization of the sample preparation, the analytical method was fully validated toward the ultra-trace quantification of six a priori selected plant hormones using three scan modes of the quadrupole-Orbitrap instrument: full-scan high-resolution mass spectrometry, targeted single ion monitoring (t-SIM), and t-SIM followed by data-dependent tandem mass spectrometry. Overall, a similar quantitative performance was noticed for the different scan modes. The analytical method was successfully applied to measure basal phytohormone levels in six different rice accessions, comprising Oryza sativa ssp. japonica, indica, and Oryza glaberrima. Hormone concentrations were higher in shoots than in roots or at least similar. Except for a lower level of salicylic acid in shoots of O. glaberrima versus O. sativa, no other differences in hormone levels could be noticed that were dependent of the (sub)species assignment of the analyzed accessions. Making use of the benefits of full-scan high-resolution mass spectrometry, a first post-run suspect screening was performed, suggesting - based on accurate mass measurements and isotopic patterns - the possible presence of about 50 additional plant hormones in the rice tissues

Vlaams Indicatorenboek 2019

Het Vlaams Indicatorenboek 2019 is een uitgave van het Expertisecentrum O&O Monitoring van de Vlaamse Gemeenschap in opdracht van de Vlaamse minister van Werk, Economie, Innovatie, en Sport en van de Vlaamse minister van Onderwijsstatus: publishe

Latin America’s new regional architecture : a cooperative or segmented regional governance complex?

In Latin America the repercussions of the proliferation and overlapping of regional organizations are discussed widely. This article examines the opposing views on this process. Some authors postulate that an exhaustion of integration in Latin America will end up in segmented regionalism and hemispheric disintegration. Others endorse a variable geometry of integration that facilitates intraregional cooperation and minimizes the risk of veto players and zero-sum politics. The article takes Latin America as a vantage point to analyse the topic of interacting and overlapping regional organizations from a more general perspective. It asks about the conditions under which the proliferation and overlapping of regional organizations might have positive or negative effects (on regional integration and cooperation). Additionally, it advocates broadening the analytical focus and replacing the analytical concepts of regional integration and cooperation with the analytical concept of regional governance. Regional governance more adequately captures and integrates different patterns of regional cooperation and different regional projects that result in overlapping regional organizations. Instead of looking at the proliferation of regional organizations from a perspective of fragmentation, this article contends that the focus should be redirected to analysing how different regional organizations interact. Regional interaction patterns can vary between synergistic, cooperative, conflictive, or segmented regional governance (complexes). In an initial application of this analytical scheme, the article summarizes the changing regional cooperation patterns in South America since 1990. In the conclusions it outlines some preliminary ideas for a future research agenda on regional governance (complexes)

Hemodynamic-effects of Corwin (ici118,587), a New Cardioselective Beta-adenoceptor Partial Agonist

We investigated a CAG trinucleotide repeat expansion in the ATXN2 gene in amyotrophic lateral sclerosis (ALS). Two new case-control studies, a British dataset of 1474 ALS cases and 567 controls, and a Dutch dataset of 1328 ALS cases and 691 controls were analyzed. In addition, to increase power, we systematically searched PubMed for case-control studies published after 1 August 2010 that investigated the association between ATXN2 intermediate repeats and ALS. We conducted a meta-analysis of the new and existing studies for the relative risks of ATXN2 intermediate repeat alleles of between 24 and 34 CAG trinucleotide repeats and ALS. There was an overall increased risk of ALS for those carrying intermediate sized trinucleotide repeat alleles (odds ratio 3.06 [95% confidence interval 2.37–3.94]; p = 6 × 10−18), with an exponential relationship between repeat length and ALS risk for alleles of 29–32 repeats (R2 = 0.91, p = 0.0002). No relationship was seen for repeat length and age of onset or survival. In contrast to trinucleotide repeat diseases, intermediate ATXN2 trinucleotide repeat expansion in ALS does not predict age of onset but does predict disease risk