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International audience; How specific interactions between plant and pathogenic, commensal, or mutualistic microorganisms are mediated and how bacteria are selected by a plant are important questions to address. Here, an Arabidopsis thaliana mutant called chs5 partially deficient in the biogenesis of isoprenoid precursors was shown to extend its metabolic remodeling to phenylpropanoids and lipids in addition to carotenoids, chlorophylls, and terpenoids. Such a metabolic profile was concomitant to increased colonization of the phyllosphere by the pathogenic strain Pseudomonas syringae pv. tomato DC3000. A thorough microbiome analysis by 16S sequencing revealed that Streptomyces had a reduced colonization potential in chs5. This study revealed that the bacteria–Arabidopsis interaction implies molecular processes impaired in the chs5 mutant. Interestingly, our results revealed that the metabolic status of A. thaliana was crucial for the specific recruitment of Streptomyces into the microbiota. More generally, this study highlights specific as well as complex molecular interactions that shape the plant microbiota.

Specialized metabolite (SM) diversification is a core process to plants’ adaptation to diverse ecological niches. Here we implemented a computational mass spectrometry (MS)-based metabolomics approach to explore SM diversification in tissues of 20 species covering Nicotiana phylogenetics sections. To drastically increase metabolite annotation, we created a large in silico fragmentation database, comprising more than 1 million structures, and scripts for connecting class prediction to consensus substructures. Altogether, the approach provides an unprecedented cartography of SM diversity and section-specific innovations in this genus. As a case-study, and in combination with NMR and MS imaging, we explored the distribution of N-acyl nornicotines, alkaloids predicted to be specific to Repandae allopolyploids, and revealed their prevalence in the genus, albeit at much lower magnitude, as well as a greater structural diversity than previously thought. Altogether, the novel data integration approaches provided here should act as a resource for future research in plant SM evolution.TeaserComputational metabolomics delineates main trends in the diversification of specialized metabolism in the genus Nicotiana

How specific interactions between plant and pathogenic, commensal, or mutualistic microorganisms are mediated and how bacteria are selected by a plant are important questions to address. Here, an

Background and purpose COVID‐19 affects the brain in various ways, amongst which delirium is worrying. An assessment was made of whether a specific, long‐lasting, COVID‐19‐related brain injury develops in acute respiratory distress syndrome patients after life‐saving re‐oxygenation. Methods Ten COVID+ patients (COVID+) with unusual delirium associated with neuroimaging suggestive of diffuse brain injury and seven controls with non‐COVID encephalopathy were studied. The assessment took place when the intractable delirium started at weaning off ventilation support. Brain magnetic resonance imaging (MRI) was performed followed by standard cerebrospinal fluid (CSF) analyses and assessment of CSF erythropoietin concentrations (as a marker for the assessment of tissue repair), and of non‐targeted CSF metabolomics using liquid chromatography high resolution mass spectrometry. Results Patients were similar as regards severity scores, but COVID+ were hospitalized longer (25 [11.75; 25] vs. 9 [4.5; 12.5] days, p = 0.03). On admission, but not at MRI and lumbar puncture performance, COVID+ were more hypoxic (p = 0.002). On MRI, there were leptomeningeal enhancement and diffuse white matter haemorrhages only in COVID+. In the latter, CSF erythropoietin concentration was lower (1.73 [1.6; 2.06] vs. 3.04 [2.9; 3.91] mIU/ml, p = 0.01), and CSF metabolomics indicated (a) increased compounds such as foodborne molecules (sesquiterpenes), molecules from industrialized beverages and micro‐pollutants (diethanolamine); and (b) decreased molecules such as incomplete breakdown products of protein catabolism and foodborne molecules (glabridin). At 3‐month discharge, fatigue, anxiety and depression as well as MRI lesions persisted in COVID+. Conclusions Some COVID+ are at risk of a specific delirium. Imperfect brain repair after re‐oxygenation and lifestyle factors might influence long‐lasting brain injuries in a context of foodborne micro‐pollutants., This explorative cohort study suggests that life‐saving re‐oxygenation of COVID+ patients is possibly followed by an incomplete brain repair as indicated by magnetic resonance imaging and low cerebrospinal fluid erythropoietin (CSF EPO) concentrations. In addition, non‐targeted metabolomics analysis identified the presence of many perturbed metabolites during COVID‐induced delirium, including biomarkers for the consumption of specific food and intermediate factors that have tangible impact on inflammatory pathways.

Position within the social group has consequences on individual lifespans in diverse taxa. This is especially obvious in eusocial insects, where workers differ in both the tasks they perform and their aging rates. However, in eusocial wasps, bees and ants, the performed task usually depends strongly on age. As such, untangling the effects of social role and age on worker physiology is a key step towards understanding the coevolution of sociality and aging. We performed an experimental protocol that allowed a separate analysis of these two factors using four groups of black garden ant (Lasius niger) workers: young foragers, old foragers, young nest workers, and old nest workers. We highlighted age-related differences in the proteome and metabolome of workers that were primarily related to worker subcaste and only secondarily to age. The relative abundance of proteins and metabolites suggests an improved xenobiotic detoxification, and a fuel metabolism based more on lipid use than carbohydrate use in young ants, regardless of their social role. Regardless of age, proteins related to the digestive function were more abundant in nest workers than in foragers. Old foragers were mostly characterized by weak abundances of molecules with an antibiotic activity or involved in chemical communication. Finally, our results suggest that even in tiny insects, extended lifespan may require to mitigate cancer risks. This is consistent with results found in eusocial rodents and thus opens up the discussion of shared mechanisms among distant taxa and the influence of sociality on life history traits such as longevity.

Position within the social group has consequences on individual lifespans in diverse taxa. This is especially obvious in eusocial insects, where workers differ in both the tasks they perform and their aging rates. However, in eusocial wasps, bees and ants, the performed task usually depends strongly on age. As such, untangling the effects of social role and age on worker physiology is a key step towards understanding the coevolution of sociality and aging. We performed an experimental protocol that allowed a separate analysis of these two factors using four groups of black garden ant (Lasius niger) workers: young foragers, old foragers, young nest workers, and old nest workers. We highlighted age-related differences in the proteome and metabolome of workers that were primarily related to worker subcaste and only secondarily to age. The relative abundance of proteins and metabolites suggests an improved xenobiotic detoxification, and a fuel metabolism based more on lipid use than carbohydrate use in young ants, regardless of their social role. Regardless of age, proteins related to the digestive function were more abundant in nest workers than in foragers. Old foragers were mostly characterized by weak abundances of molecules with an antibiotic activity or involved in chemical communication. Finally, our results suggest that even in tiny species, extended lifespan may require to mitigate cancer risks. This is consistent with results found in eusocial rodents and thus opens up the discussion of shared mechanisms among distant taxa and the influence of sociality on life history traits such as longevity.

SummaryChromatin is a dynamic platform within which gene expression is controlled by epigenetic modifications, notably targeting amino acid residues of histone H3. Among them is Lysine 27 of H3 (H3K27), which trimethylation by the Polycomb Repressive Complex 2 (PRC2) is instrumental in regulating spatio-temporal patterns of key developmental genes. H3K27 is also subjected to acetylation, found at sites of active transcription. Most information on the function of histone residues and their associated modifications in plants was obtained from studies of loss-of-function mutants for the complexes that modify them.In order to decrypt the genuine function of H3K27, we expressed a non-modifiable variant of H3 at residue K27 (H3.3K27A) in Arabidopsis, and developed a multi-scale approach combining in-depth phenotypical and cytological analyses, with transcriptomics and metabolomics.We uncovered that the H3.3K27A variant causes severe developmental defects, part of them reminiscent of PRC2 mutants, part of them new. They include early flowering, increased callus formation, and short stems with thicker xylem cell layer. This latest phenotype correlates with mis-regulation of phenylpropanoid biosynthesis.Overall, our results reveal novel roles of H3K27 in plant cell fates and metabolic pathways, and highlight an epigenetic control point for elongation and lignin composition of the stem.

International audience; Ultrahigh resolution mass spectrometry (UHR-MS) coupled with direct infusion (DI) electrospray ionization offers a fast solution for accurate untargeted profiling. Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometers have been shown to produce a wealth of insights into complex chemical systems because they enable unambiguous molecular formula assignment even if the vast majority of signals is of unknown identity. Interlaboratory comparisons are required to apply this type of instrumentation in quality control (for food industry or pharmaceuticals), large-scale environmental studies, or clinical diagnostics. Extended comparisons employing different FT-ICR MS instruments with qualitative direct infusion analysis are scarce since the majority of detected compounds cannot be quantified. The extent to which observations can be reproduced by different laboratories remains unknown. We set up a preliminary study which encompassed a set of 17 laboratories around the globe, diverse in instrumental characteristics and applications, to analyze the same sets of extracts from commercially available standard human blood plasma and Standard Reference Material (SRM) for blood plasma (SRM1950), which were delivered at different dilutions or spiked with different concentrations of pesticides. The aim of this study was to assess the extent to which the outputs of differently tuned FT-ICR mass spectrometers, with different technical specifications, are comparable for setting the frames of a future DI-FT-ICR MS ring trial. We concluded that a cluster of five laboratories, with diverse instrumental characteristics, showed comparable and representative performance across all experiments, setting a reference to be used in a future ring trial on blood plasma.

The social organization of many primate, bird and rodent species and the role of individuals within that organization are associated with specific individual physiological traits. However, this association is perhaps most pronounced in eusocial insects (e.g., termites, ants). In such species, genetically close individuals show significant differences in behavior, physiology, and life expectancy. Studies addressing the metabolic changes according to the social role are still lacking. We aimed at understanding how sociality could influence essential molecular processes in a eusocial insect, the black garden ant (Lasius niger) where queens can live up to ten times longer than workers. Using mass spectrometry-based analysis, we explored the whole metabolome of queens, nest-workers and foraging workers. A former proteomics study done in the same species allowed us to compare the findings of both approaches. Confirming the former results at the proteome level, we showed that queens had fewer metabolites related to immunity. Contrary to our predictions, we did not find any metabolite linked to reproduction in queens. Among the workers, foragers had a metabolic signature reflecting a more stressful environment and a more highly stimulated immune system. We also found that nest-workers had more digestion-related metabolites. Hence, we showed that specific metabolic signatures match specific social roles. Besides, we identified metabolites differently expressed among behavioral castes and involved in nutrient sensing and longevity pathways (e.g., sirtuins, FOXO). The links between such molecular pathways and aging being found in an increasing number of taxa, our results confirm and strengthen their potential universality.

International audience; Background: Hypertension is a major cardiovascular risk factor that affects most countries including those of Africa. Although Carissa edulis Vahl, Diodia scandens Sw. and Cleome gynandra L. are traditionally used in Benin as antihypertensive treatments with some efficacy mentioned by the local population, their biological activity on the cardiovascular system remains poorly studied.Aim: The study investigated the vasoreactivity of the plants and assessed the underlying mechanisms using isolated arteries.Study design: Aqueous-ethanolic extracts of aerial parts of C. edulis, D. scandens and C. gynandra were prepared by maceration before being subjected to multi-step liquid-liquid fractionation with solvents of increasing polarity. The vasoreactivity of the extracts and fractions were assessed on isolated porcine coronary artery and rat aorta using organ chambers, the role of nitric oxide (NO) using NG-nitro-L-arginine (NO synthase inhibitor), prostanoids using indomethacin (cyclooxygenases inhibitor) and endothelium-dependent hyperpolarization using TRAM-34 plus UCL 1684 (inhibitors of calcium-dependent K+ channels), and the vascular uptake of polyphenols using Neu reagent.Results: The aqueous-ethanolic crude extract of C. edulis (CECE) induced potent relaxations that were exclusively endothelium-dependent and more pronounced than those to D. scandens and C. gynandra. The n-butanolic fraction of C. edulis (CEBF) was more active than the cyclohexane, dichloromethane, and ethyl acetate fractions. The relaxation induced by CECE and CEBF were inhibited by NG-nitro-L-arginine and affected neither by TRAM-34 plus UCL 1684 nor by indomethacin. CEBF induced sustained endothelium-dependent relaxations for at least 60 min, and inhibited, in a concentration-dependent manner, contractions to KCl, CaCl2, U46619 and serotonin in rings with endothelium. Analysis of CEBF by LCsingle bondHRMS indicated the presence of polyphenols, terpenes, and alkaloids. Exposure of coronary artery and aorta rings to CEBF caused the accumulation of polyphenols predominantly in the endothelium.Conclusion: C. edulis leaf extract induced pronounced endothelium-dependent relaxations and inhibited contractile responses by stimulating the endothelial formation of NO. LCsingle bondHRMS analysis of the most active fraction, the butanolic fraction, revealed the presence of numerous compounds including polyphenols, terpenes, and alkaloids. The polyphenols of CEBF accumulated preferentially in the endothelium of the arterial wall. Thus, these observations support the folkloric use of C. edulis in hypertension.

In human society, there is a demand for sustainable solutions for water preservation and efficient treatment systems. An important water reservoir is road runoff defined as rainwater leaching from roads, loading micropollutants and infiltrating the soil. We aimed to study this poorly understood feature using large-scale metabolomic analysis coupled with analysis of soil physico-chemical properties and molecular chemical similarity enrichment. A total of 2406 micropollutants were assayed to understand their distribution and assess the trapping abilities of a road runoff infiltration system composed of a sedimentation pond and an infiltration pond. Here, we confirm the essential role of the infiltration pond in preventing environmental contamination and propose a model correlating micropollutant abundance and the soil physico-chemical properties. We demonstrate that sand in infiltration ponds is a key player, helping retain 86% of the micropollutant abundance and propose a model that could be easily applied for road runoff management.

Jasmonate signaling for adaptative or developmental responses generally relies on an increased synthesis of the bioactive hormone jasmonoyl-isoleucine (JA-Ile), triggered by environmental or internal cues. JA-Ile is embedded in a complex metabolic network whose upstream and downstream components strongly contribute to hormone homeostasis and activity. We previously showed that JAO2, an isoform of four Arabidopsis JASMONIC ACID OXIDASES, diverts the precursor jasmonic acid (JA) to its hydroxylated form HO-JA to attenuate JA-Ile formation and signaling. Consequently, JAO2-deficient lines have elevated defenses and display improved tolerance to biotic stress. Here we further explored the organization and regulatory functions of the JAO pathway. Suppression of JAO2 enhances the basal expression of nearly 400 JA-regulated genes in unstimulated leaves, many of which being related to biotic and abiotic stress responses. Consistently, non-targeted metabolomic analysis revealed the constitutive accumulation of several classes of defensive compounds in jao2-1 mutant, including indole glucosinolates and breakdown products. The most differential compounds were agmatine phenolamides, but their genetic suppression did not alleviate the strong resistance of jao2-1 to Botrytis infection. Furthermore, jao2 alleles and a triple jao mutant exhibit elevated survival capacity upon severe drought stress. This latter phenotype occurs without recruiting stronger abscisic acid responses, but relies on enhanced JA-Ile signaling directing a distinct survival pathway with MYB47 transcription factor as a candidate mediator. Our findings reveal the selected spectrum of JA responses controlled by the JAO2 regulatory node and highlight the potential of modulating basal JA turnover to pre-activate mild transcriptional programs for multiple stress resilience.

Current approaches are often limited to evaluating the contribution of pesticide dissipation processes in water-sediment systems as both degradation and phase transfer, that is, sorption-desorption, contribute to the apparent decrease of pesticide concentration. Here, the dissipation of widely used herbicides acetochlor and S-metolachlor was examined in laboratory by water-sediment microcosm experiments under oxic and anoxic conditions. Compound-specific isotope analysis (CSIA) emphasized insignificant carbon isotope fractionation in the sediment, indicating prevailing pesticide degradation in the water phase. Conceptual modeling accounting for phase transfer and biodegradation indicated that biodegradation may be underestimated when phase transfer is not included. Phase transfer does not affect carbon isotope fractionation for a wide spectrum of molecules and environmental conditions, underscoring the potential of pesticide CSIA as a robust approach to evaluate degradation in water-sediment systems. CSIA coupled with the identification of transformation products by high-resolution tandem mass spectrometry suggests the degradation of acetochlor and S-metolachlor to occur via nucleophilic substitution and the predominance of oxalinic acids as transformation products under both anoxic and oxic conditions. Altogether, combining the pesticide CSIA, the identification of transformation products, and the use of conceptual phase-transfer models improves the interpretation of pesticide dissipation in water-sediment systems.

International audience; Introduction: Gestational age at delivery seems to be a risk factor of recurrence of preeclampsia. The objective of this study was to analyze adverse pregnancy outcomes and recurrence of preeclampsia during the subsequent pregnancy in women with a history of pre-eclampsia delivered before 26 weeks of gestation.Material and method: We performed a retrospective study in two French tertiary care hospitals between 2000 and 2018. Patients with a history of pre-eclampsia delivered before 26 weeks of gestation were analyzed. Information on the immediate subsequent pregnancy was collected. Adverse composite outcome was defined as recurrent preeclampsia, HELLP syndrome, placental abruption, fetal growth restriction

International audience; Conventional wastewater treatment plants are not designed to treat micropollutants; thus, for 20 years, several complementary treatment systems, such as surface flow wetlands have been used to address this issue. Previous studies demonstrate that higher residence time and low global velocities promote nutrient removal rates or micropollutant photodegradation. Nevertheless, these studies were restricted to the system limits (inlet/outlet). Therefore, detailed knowledge of water flow is crucial for identifying areas that promote degradation and optimise surface flow wetlands. The present study combines 3D water flow numerical modelling and liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS/MS). Using this numerical model, validated by tracer experimental data, several velocity areas were distinguished in the wetland. Four areas were selected to investigate the waterflow influence and led to the following results: on the one hand, the number and concentration of micropollutants are independent of the waterflow, which could be due to several assumptions, such as the chronic exposure associated with a low Reynolds number; on the other hand, the potential degradation products (metabolites) were also assessed in the sludge to investigate the micropollutant biodegradation processes occurring in the wetland; micropollutant metabolites or degradation products were detected in higher proportions (both number and concentration) in lower flow rate areas. The relation to higher levels of plant and microorganism metabolites suggests higher biological activity that promotes degradation.

Increased metabolism is one of the main causes for evolution of herbicide resistance in weeds, a major challenge for sustainable food production. The molecular drivers of this evolution are poorly understood. We tested here the hypothesis that a suitable context for the emergence of herbicide resistance could be provided by plant enzymes with high innate promiscuity with regard to their natural substrates. A selection of yeast-expressed plant cytochrome P450 enzymes with well documented narrow to broad promiscuity when metabolizing natural substrates was tested for herbicide metabolism competence. The positive candidate was assayed for capacity to confer herbicide tolerance in Arabidopsis thaliana. Our data demonstrate that Arabidopsis thaliana CYP706A3, with the most promiscuous activity on monoterpenes and sesquiterpenes for flower defence, can also oxidize plant microtubule assembly inhibitors, dinitroanilines. Ectopic overexpression of CYP706A3 confers dinitroaniline resistance. We show, in addition, that the capacity to metabolize dinitroanilines is shared by other members of the CYP706 family from plants as diverse as eucalyptus and cedar. Supported by three-dimensional (3D) modelling of CYP706A3, the properties of enzyme active site and substrate access channel are discussed together with the shared physicochemical properties of the natural and exogenous substrates to explain herbicide metabolism.

Vismione H (VH) is a fluorescent prenylated anthranoid produced by plants from the Hypericaceae family, with antiprotozoal activities against malaria and leishmaniosis. Little is known about its biosynthesis and metabolism in plants or its mode of action against parasites. When VH is isolated from Psorospermum glaberrimum, it is rapidly converted into madagascine anthrone and anthraquinone, which are characterized by markedly different fluorescent properties. To locate the fluorescence of VH in living plant cells and discriminate it from that of the other metabolites, an original strategy combining spectral imaging (SImaging), confocal microscopy and non-targeted metabolomics using mass spectrometry, was developed. Besides VH, structurally related molecules including madagascine, emodin, quinizarin as well as lapachol and fraxetin were analyzed. This strategy readily allowed a spatiotemporal characterization and discrimination of spectral fingerprints from anthranoids-derived metabolites and related complexes with cations and proteins. In addition, our study validates the capability of plant cells to metabolize VH into madagascine anthrone, anthraquinones and unexpected metabolites, leading to new hypotheses on the metabolism of anthranoids in plants.

International audience; Sulfur metabolism in fuel-biodesulfurizing bacteria and the underlying physiological adaptations are not understood, which has impeded the development of a commercially viable bioprocess for fuel desulfurization. To fill these knowledge gaps, we performed comparative proteomics and untargeted metabolomics in cultures of the biodesulfurization reference strain Rhodococcus qingshengii IGTS8 grown on either inorganic sulfate or the diesel-borne organosulfur compound dibenzothiophene as a sole sulfur source. Dibenzothiophene significantly altered the biosynthesis of many sulfur metabolism proteins and metabolites in a growth phase-dependent manner, which enabled us to reconstruct the first experimental model for sulfur metabolism in a fuel-biodesulfurizing bacterium. All key pathways related to assimilatory sulfur metabolism were represented in the sulfur proteome, including uptake of the sulfur sources, sulfur acquisition, and assimilatory sulfate reduction, in addition to biosynthesis of key sulfur-containing metabolites such as S-adenosylmethionine, coenzyme A, biotin, thiamin, molybdenum cofactor, mycothiol, and ergothioneine (low-molecular weight thiols). Fifty-two proteins exhibited significantly different abundance during at least one growth phase. Sixteen proteins were uniquely detected and 47 proteins were significantly more abundant in the dibenzothiophene culture during at least one growth phase. The sulfate-free dibenzothiophene-containing culture reacted to sulfate starvation by restricting sulfur assimilation, enforcing sulfur-sparing, and maintaining redox homeostasis. Biodesulfurization triggered alternative pathways for sulfur assimilation different from those operating in the inorganic sulfate culture. Sulfur metabolism reprogramming and metabolic switches in the dibenzothiophene culture were manifested in limiting sulfite reduction and biosynthesis of cysteine, while boosting the production of methionine via the cobalamin-independent pathway, as well as the biosynthesis of the redox buffers mycothiol and ergothioneine. The omics data underscore the key role of sulfur metabolism in shaping the biodesulfurization phenotype and highlight potential targets for improving the biodesulfurization catalytic activity via metabolic engineering. IMPORTANCE For many decades, research on biodesulfurization of fossil fuels was conducted amid a large gap in knowledge of sulfur metabolism and its regulation in fuel-biodesulfurizing bacteria, which has impeded the development of a commercially viable bioprocess. In addition, lack of understanding of biodesulfurization-associated metabolic and physiological adaptations prohibited the development of efficient biodesulfurizers. Our integrated omics-based findings reveal the assimilatory sulfur metabolism in the biodesulfurization reference strain Rhodococcus qingshengii IGTS8 and show how sulfur metabolism and oxidative stress response were remodeled and orchestrated to shape the biodesulfurization phenotype. Our findings not only explain the frequently encountered low catalytic activity of native fuel-biodesulfurizing bacteria but also uncover unprecedented potential targets in sulfur metabolism that could be exploited via metabolic engineering to boost the biodesulfurization catalytic activity, a prerequisite for commercial application.

Wastewater is one of the major sources of micropollutant release into the environment. In order to reduce the impact of wastewater, wastewater treatment plants (WWTP) have been set up, in the instance of vertical flow constructed wetlands (VFCWs). Besides, micropollutants could represent a vast diversity of compounds and compound's choice could bias studies focused on their fate. To overcome this bias, non-targeted screening approaches can be performed. Therefore, the diffusion of micropollutants from raw wastewater in the VFCW compartments (wastewater, plants and sludge) as well as their fate have been investigated using this non-target approach with liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) and gas chromatography (GC) coupled to mass spectrometry. To help the operators in their sludge management, this study will be focused on the following question: Is there a specific distribution of micropollutants according to sludge layers? To eliminate the background contamination found both inside the CW and in the surrounding environment, a control coring was performed in bank. A specific distribution could be observed in the top (191 compounds) and bottom layers (38 compounds). However, a distribution over the whole depth for xenobiotics was observed. Micropollutants classes and the main microbial productivity were preferably found in the top layer. The micropollutants fate could however not be restricted to the sludge compartment. Therefore, the specific micropollutants distribution was analyzed in the outputs of the system in their interactions with wastewater (effluent, sludge, and reed rhizomes) to understand their fate. In our study, the results highlighted a consistent part of compounds found in at least two or three of these compartments, with a similar trend in each compartment. These results underline the interactions between the compartments and the global issues of micropollutants distribution as well as its wide spreading in the whole CW ecosystem.

To improve and complete our knowledge of archaeal tRNA modification patterns, we have identified and compared the modification pattern (type and location) in tRNAs of three very different archaeal species, Methanococcus maripaludis (a mesophilic methanogen), Pyrococcus furiosus (a hyperthermophile thermococcale), and Sulfolobus acidocaldarius (an acidophilic thermophilic sulfolobale). Most abundant isoacceptor tRNAs (79 in total) for each of the 20 amino acids were isolated by two-dimensional gel electrophoresis followed by in-gel RNase digestions. The resulting oligonucleotide fragments were separated by nanoLC and their nucleotide content analyzed by mass spectrometry (MS/MS). Analysis of total modified nucleosides obtained from complete digestion of bulk tRNAs was also performed. Distinct base- and/or ribose-methylations, cytidine acetylations, and thiolated pyrimidines were identified, some at new positions in tRNAs. Novel, some tentatively identified, modifications were also found. The least diversified modification landscape is observed in the mesophilic Methanococcus maripaludis and the most complex one in Sulfolobus acidocaldarius Notable observations are the frequent occurrence of ac4C nucleotides in thermophilic archaeal tRNAs, the presence of m7G at positions 1 and 10 in Pyrococcus furiosus tRNAs, and the use of wyosine derivatives at position 37 of tRNAs, especially those decoding U1- and C1-starting codons. These results complete those already obtained by others with sets of archaeal tRNAs from Methanocaldococcus jannaschii and Haloferax volcanii., SCOPUS: ar.j, info:eu-repo/semantics/published

Synthetic biology has potential spaceflight applications yet few if any studies have attempted to translate Earth-based synthetic biology tools into spaceflight. An exogenously inducible biological circuit for protein production in Arabidopsis thaliana, pX7-AtPDSi (Guo et al. 2003), was flown to ISS and functionally investigated. Seedlings were grown in a custom built 1.25 U plant greenhouse. Images recorded during the experiment show that leaves of pX7-AtPDSi seedlings photobleached as designed while wild type Col-0 leaves did not, which reveals that the synthetic circuit led to protein production during spaceflight. Polymerase chain reaction analysis post-flight also confirms that the Cre/LoxP (recombination system) portions of the circuit were functional in spaceflight. The subcomponents of the biological circuit, estrogen-responsive transcription factor XVE, Cre/LoxP DNA recombination system, and RNAi post-transcriptional gene silencing system now have flight heritage and can be incorporated in future designs for space applications. To facilitate future plant studies in space, the full payload design and manufacturing files are made available.

Study Objective To compare the outcomes of hysteroscopic management in women with a severe or nonsevere symptomatic cesarean scar defect (residual myometrium ≤3-mm vs >3-mm, respectively). Design Retrospective cohort study. Setting Gynecology department of a teaching hospital. Patients Seventy-one women with an operative hysteroscopy for a symptomatic defect (49 with severe defects and 22 with nonsevere ones). Interventions Operative hysteroscopy for cesarean scar defect in women with a severe defect (residual myometrium ≤3-mm) and with nonsevere defect (residual myometrium >3-mm). Measurements The main objective was to compare success rates between the 2 groups. The secondary objectives were the comparisons of (1) the number of women who required more than 1 procedure, (2) the rate of complications, (3) the number of subsequent pregnancies, and (4) the evolution of residual myometrium thickness between the groups. Main Results The success rates were not significantly different between the groups (73.5% in the severe group and 63.6% in the nonsevere group [p = .40]). The number of women requiring more than 1 procedure was also similar, as were the rate of complications and the mean increase of myometrium thickness. The rate of subsequent pregnancies in women who were infertile was significantly higher in women with a severe defect (p = .04). Conclusion The hysteroscopic approach seems to be a good way to manage cesarean scar defects even when the residual myometrium is thin. A prospective study is, however, necessary to confirm these findings.

The method presented uses mass spectrometry imaging (MSI) to establish the metabolic profile of S. alba leaves when exposed to xenobiotics. Using a non-targeted approach, plant metabolites and xenobiotics of interest are identified and localized in plant tissues to uncover specific distribution patterns. Then, in silico prediction of potential metabolites (i.e., catabolites and conjugates) from the identified xenobiotics is performed. When a xenobiotic metabolite is located in the tissue, the type of enzyme involved in its alteration by the plant is recorded. These results were used to describe different types of biological reactions occurring in S. alba leaves in response to xenobiotic accumulation in the leaves. The metabolites were predicted in two generations, allowing the documentation of successive biological reactions to transform xenobiotics in the leaf tissues.

The method presented uses mass spectrometry imaging (MSI) to establish the metabolic profile of S. alba leaves when exposed to xenobiotics. Using a non-targeted approach, plant metabolites and xenobiotics of interest are identified and localized in plant tissues to uncover specific distribution patterns. Then, in silico prediction of potential metabolites (i.e., catabolites and conjugates) from the identified xenobiotics is performed. When a xenobiotic metabolite is located in the tissue, the type of enzyme involved in its alteration by the plant is recorded. These results were used to describe different types of biological reactions occurring in S. alba leaves in response to xenobiotic accumulation in the leaves. The metabolites were predicted in two generations, allowing the documentation of successive biological reactions to transform xenobiotics in the leaf tissues.

To compare stimulated cycle (STC) versus modified natural cycle (MNC) for endometrial preparation prior to frozen embryo transfer (FET) in terms of convenience and efficacy.Prospective, open-label, randomized controlled study including 119 patients aged 20-38 years, undergoing intra-conjugal IVF/intracytoplasmic sperm injection, having regular cycles, at least two day 2 or day 3 frozen embryos, for whom it was the first or second FET performed, randomized to either MNC (n = 59) or STC (n = 60). Monitoring consisted of ultrasound and hormonal measurements. The number of monitoring visits required was compared between the two groups.STC required a significantly lower number of monitoring visits compared with MNC (3.6 ± 0.9 versus 4.4 ± 1.1, respectively, P 0.0001), a lower number of blood tests (2.7 ± 0.8 versus 3.5 ± 1.0, respectively, P 0.0001) and of ultrasounds (1.2 ± 0.4 versus 1.5 ± 0.6, respectively, P = 0.0039). FET during 'non-opening' hours (22.6% versus 27.5%, respectively, P = 0.32) and cancellation rates (11.7% versus 11.9%, respectively, P = 0.97) were comparable between the STC and MNC groups. No difference concerning HCG-positive rates (34.0% versus 23.1%, respectively, P = 0.22) nor live birth rates (24.5% for STC versus 23.1% for MNC, respectively, P = 0.86) was observed. Quality of life as defined by the FertiQol score was not different (P 0.05 for each item).Altogether, these findings can be used for everyday clinical practice to better inform patients when deciding on the protocol to use for FET. These results suggest that MNC is a good option for patients reluctant to have injections, but requires increased monitoring. STC may offer more flexibility for patients and IVF centres.

Purpose Produce a precision dosing application for clinicians to control neutropenia in patients treated with both docetaxel and G-CSF. Context Chemotherapy induced neutropenia (CIN) poses serious harm to patients due to the heightened risk of severe infection. Accordingly, chemotherapy dose is assessed at the beginning of each cycle. The therapeutic window of chemotherapy is determined from population studies, with an individual's dose often scaled by their body surface area. This leads to a large number of patients being over- or under- dosed. We previously developed an application [1] which uses weekly neutrophil counts from the first cycle of docetaxel treatment to predict the level of neutropoenia in subsequent cycles for a given dose of docetaxel. However, in the original app the administration of G-CSF, used as a prophylactic treatment for neutropenia, was not considered. G-CSF administration lacks standardisation and the COVID-19 pandemic has created a highly risk averse environment to infections, raising the prospects that a clinician will administer G-CSF. MethodsAiming to predict the level of neutropenia after the first cycle we draw from models in the literature of CIN for G-CSF treated patients [2,3,4]. We adapt the G-CSF induced feedback effect on neutrophil development in these models to account for features specific to docetaxel patients; notably the rebound in neutrophils above baseline seen after nadir [5], and the apparent short maturation time of neutrophils [4]. Using data in the public domain from the comparator arm of a phase III clinical trial for metastatic hormone-resistant prostate cancer (clinical trial number NCT00617669), we identify 27 patients treated with docetaxel and G-CSF with weekly blood tests in the first and second cycle. We calibrate our model by minimising a Bayesian objective function to establish a model that predicts the neutrophil count in the second docetaxel cycle from the first. We then simulate the effect of different combinations of docetaxel, G-CSF, and the timing of G-CSF administration. Conclusions Current progress includes a model which captures the rebound above baseline in neutrophil count seen in docetaxel patients. We will show that our model captures the effect of filgrastim and pegfilgrastim on neutrophil counts, and can determine how a docetaxel patient may best benefit from G-CSF treatment and/or a change in dose of docetaxel. References 1. Villettte C., et al., Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 677. 2. Pastor, M.L., et al. 2013. Pharmaceutical research, 30(11), pp.2795-2807. 3. Melhem, M. et al., 2018. British journal of clinical pharmacology, 84(5), pp.911-925. 4. Quartino, A.L et al., 2014. Pharmaceutical research, 31(12), pp.3390-3403. 5. Friberg, L.E., et al., 2002. Journal of clinical oncology, 20(24), pp.4713-4721. Citation Format: Christian Hurry, Claire Villette, Hitesh Mistry, Jim Millen, Christophe Chassagnole. A precision dosing application for patients treated with docetaxel and G-CSF [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 228.

e13585 Background: The aim of this study is to produce a precision dosing application for clinicians to control neutropenia in prostate cancer patients treated with both docetaxel and G-CSF. Chemotherapy-induced neutropenia (CIN) poses serious harm to patients due to the heightened risk of severe infection. Accordingly, chemotherapy dose is assessed at the beginning of each cycle. The therapeutic window of chemotherapy is determined from population studies, with an individual’s dose often scaled by their body surface area. This leads to a large number of patients being over- or under- dosed. We previously developed an application [1] which uses weekly neutrophil counts from the first cycle of docetaxel treatment to predict the level of neutropoenia in subsequent cycles for a given dose of docetaxel. However, in the original app the administration of G-CSF, used as a prophylactic treatment for neutropenia, was not considered. G-CSF administration lacks standardisation and the COVID-19 pandemic has created a highly risk adverse environment to infections, raising the prospects that a clinician will administer G-CSF. Methods: We adapted and combined representations of endogenous and exogenous G-CSF action on CIN from the literature [2,3,4] to capture the inherent feedback effect of circulating neutrophils on progenitor proliferation as well as the stimulatory action of G-CSF injection on proliferation and maturation of progenitor cells. Using data in the public domain from the comparator arm of a phase III clinical trial for metastatic hormone-resistant prostate cancer (NCT00617669), we identified 134 patients treated with docetaxel with recorded weekly blood tests in the first and second cycle, including 27 also receiving G-CSF. We calibrated individualised patient models against neutrophil counts measured in the first cycle by minimising a Bayesian objective function and evaluated their ability to predict the levels observed in the second cycle. Results: The model was able to capture the main features of endogenous and exogenous G-CSF action on neutrophil count described in the literature, including endogenous-G-CSF-mediated rebound above baseline after chemotherapy-induced depletion [4], rapid rise in neutrophil count following exogenous G-CSF administration [5], as well as reduced chemotherapy-induced depletion and earlier recovery under G-CSF treatment compared to chemotherapy alone [5]. Conclusions: This tool has the potential to help determine how a docetaxel patient may best benefit from G-CSF treatment and/or a change in dose of docetaxel. References: Villettte C., et al., AACR; Cancer Res, 2019;79(13 Suppl): Abstract nr 677. Pastor, M.L., et al. 2013. Pharm. Res, 30(11), pp.2795-2807. Krzyzanski, W., et al. 2010. J. Clin. Pharmacol, 50(S9), pp.101S-112S. Quartino, A.L et al., 2014. Pharm. Res, 31(12), pp.3390-3403. Crawford, J., et al. 1991. N. Engl. J. Med, 325(3), pp.164-170.

Micropollutants are increasingly monitored as their presence in the environment is rising due to human activities, and they are potential threats to living organisms. This study aimed at understanding the role of plants in xenobiotics removal from polluted environments by following xenobiotics metabolism in leaf tissues. Different classes of micropollutants were investigated using liquid chromatography (LC) coupled to quadrupole-time of flight (Q-TOF) high resolution mass spectrometry (HRMS). The tissue localization of xenobiotics in the leaves of a spontaneous (not planted by humans) Salix alba growing near the water flux was further investigated using matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI). The LC-Q-TOF analysis revealed the distribution of micropollutants in three different compartments of a tertiary treatment wetland. When further investing the metabolic profile of S. alba leaves using MSI, different distribution patterns were observed in specific leaf tissues. Xenobiotic metabolites were predicted and could also be tentatively identified in S. alba leaves, shedding new light on the metabolic processes at play in leaves to manage xenobiotics uptake from a polluted environment. Using complementary metabolomics approaches, this study performed a large-scale exploration of micropollutants spreading in the environment at the exit of a tertiary treatment wetland. The use of MSI coupled with the prediction of xenobiotic metabolites yielded novel insights into plant metabolism during chronical exposure to low doses of a mixture of micropollutants.

Barley (Hordeum vulgare) is the fourth crop cultivated in the world for human consumption and animal feed, making it important to breed healthy and productive plants. Among the threats for barley are lodging, diseases, and pathogens. To avoid lodging, dwarf and semi-dwarf mutants have been selected through breeding processes. Most of these mutants are affected on hormonal biosynthesis or signalling. Here, we present the metabolic characterization of a brassinosteroid insensitive semi-dwarf mutant, BW312. The hormone profile was determined through a targeted metabolomics analysis by UHPLC-triple quadrupole-MS/MS, showing an induction of gibberellic acid and jasmonic acid in the semi-dwarf mutant. A non-targeted metabolomics analysis by UHPLC-QTOF-MS/MS revealed a differential metabolic profile, with 16 and 9 metabolites showing higher intensities in the mutant and wild-type plants respectively. Among these metabolites, azelaic acid was identified. Gibberellic acid, jasmonic acid, and azelaic acid are involved in pathogen resistance, showing that this semi-dwarf line has an enhanced basal pathogen resistance in absence of pathogens, and therefore is of interest in breeding programs to fight against lodging, but also probably to increase pathogen resistance.

Vitamin D3 is a secosterol hormone critical for bone growth and calcium homeostasis, produced in vertebrate skin by photolytic conversion of the cholesterol biosynthetic intermediate provitamin D3. Insufficient levels of vitamin D3 especially in the case of low solar UV-B irradiation is often compensated by an intake of a dietary source of vitamin D3 of animal origin. Small amounts of vitamin D3 were described in a few plant species and considered as a peculiar feature of their phytochemical diversity. In this report we show the presence of vitamin D5 in the model plant Arabidopsis thaliana. This plant secosterol is a UV-B mediated derivative of provitamin D5, the precursor of sitosterol. The present work will allow a further survey of vitamin D distribution in plant species.

Here we have examined the composition of free sterols and steryl esters of pollen from selected angiosperm species, as a first step towards a comprehensive analysis of sterol biogenesis in the male gametophyte. We detected four major sterol structural groups: cycloartenol derivatives bearing a 9β,19-cyclopropyl group, sterols with a double bond at C-7(8), sterols with a double bond at C-5(6), and stanols. All these groups were unequally distributed among species. However, the distribution of sterols as free sterols or as steryl esters in pollen grains indicated that free sterols were mostly Δ(5)-sterols and that steryl esters were predominantly 9β,19-cyclopropyl sterols. In order to link the sterol composition of a pollen grain at anthesis with the requirement for membrane lipid constituents of the pollen tube, we germinated pollen grains from Nicotiana tabacum, a model plant in reproductive biology. In the presence of radiolabelled mevalonic acid and in a time course series of measurements, we showed that cycloeucalenol was identified as the major neosynthesized sterol. Furthermore, the inhibition of cycloeucalenol neosynthesis by squalestatin was in full agreement with a de novo biogenesis and an apparent truncated pathway in the pollen tube.

Vitamin D3 is a secosterol hormone critical for bone growth and calcium homeostasis, produced in vertebrate skin by photolytic conversion of the cholesterol biosynthetic intermediate provitamin D3. Insufficient levels of vitamin D3 especially in the case of low solar UV-B irradiation is often compensated by an intake of a dietary source of vitamin D3 of animal origin. Small amounts of vitamin D3 were described in a few plant species and considered as a peculiar feature of their phytochemical diversity. In this report we show the presence of vitamin D5 in the model plant Arabidopsis thaliana. This plant secosterol is a UV-B mediated derivative of provitamin D5, the precursor of sitosterol. The present work will allow a further survey of vitamin D distribution in plant species.

Objective To study possible associations among endometriosis, pelvic infectious disease, and ART. Design Retrospective cohort analysis over 4 consecutive years, based on medical records and insurance coding in a tertiary endometriosis reference center. Setting Tertiary university-based reference center for endometriosis. Patient(s) We retrieved all charts carrying the diagnoses infectious process and endometriosis in 2009–2012. Each chart was individually analyzed for categorization of the infectious episode and determining whether ART had been performed. Main Outcome Measure(s) Hospitalization for acute infection in women with known endometriosis and possible past ART. Intervention Retrospective insurance codes–triggered chart analysis. Result(s) Ten patients were admitted for an acute infection with fever, acute abdomen syndrome, elevated white blood cell count, and adnexal mass. Three women had oocyte retrieval, and an endometrioma was present 16, 57, and 102 days earlier. In one patient, the complication occurred 37 days after a cesarean section without prior ART. In the remaining six cases tubo-ovarian abscesses (TOAs) occurred spontaneously in endometriosis women who never had ART. Medical treatment succeeded in only two patients, and the remaining eight needed laparoscopic drainage. In 6 out of those 8 cases, laparoscopic drainage was a second-stage measure justified by failure to respond to antibiotic therapy. Conclusion(s) Our data indicate that some putative complications of ART and endometrioma may actually not be linked to ART, but rather constitute sporadic occurrences in endometriosis. Furthermore, TOAs occurring in women with endometriosis are best treated by early surgical drainage together with intravenous antibiotics.

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