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Après création dans une couche de charbon d'une communication entre deux forages, la gazéification in situ vise à réaliser l'extraction de l'énergie du charbon grâce au soutirage par l'un des puits de gaz combustible résultant de la combinaison du charbon en place avec les réactifs gazeux injectés par l'autre puits. Si une méthode de mise en communication des forages peut être découverte pour des couches de charbon profondes (plus de 800 m) il restera à déterminer comment conduire l'opération de gazéification et à évaluer la quantité de gaz, susceptible de méthanation, récupérable, dans un gisement donné, par un doublet de forages ; cette quantité gouverne en effet l'intérêt économique de l'opération. Un recensement des couches de charbon situées en France au delà de 800 m de profondeur, d'épaisseur au moins égale à 2 m et que rien n'empêche actuellement de considérer comme utilisables pour le procédé fournit une estimation totale, avec pondération suivant l'incertitude, de 2 milliards de tonnes. L'ampleur de ces ressources incite sur le plan français à s'efforcer d'établir si le procédé de gazéification souterraine permet leur récupération à un coût acceptable. Sur le plan mondial l'enjeu est, bien entendu, encore plus considérable. After a communication has been created between two boreholes in a Goal bed, insitu gasification is a way of trying to extract the energy contained tn the coal by with-drowing, via one of the wells, the combustible gas resulting from the combination of the Goal in place with gaseous reactants injected via the other well. If a method con be discovered for creating a communication betwen boreholes for deep Goal beds (deeper than 800 m), a method will still have ta be discovered for carrying out the gasification operation and for evaluating the amount of gas available for methanationthot is recoverable in a given deposit via a pair of boreholes. This amount effectively governs the economic feasibility of the operation. A survey of carbon beds in France located at depths greater than 800 m and at least 2 m thick, and which nothing now prevents from being considered as usable for the process, gives on overall estimate of 2 billion tons, with weighting according ta the degree of uncertainty. From the French standpoint, the size of these resources is an encouragement to determine whether the underground gasification process will enable them ta be recovered at an acceptable cost. From the worldwide stanpoint, the stokes are, of course, much greater.

RATIONALE: Fluid accumulation in the legs and its overnight redistribution into the neck appears to play a causative role in obstructive sleep apnea (OSA) in sedentary men. Chronic venous insufficiency (CVI) promotes fluid accumulation in the legs that can be counteracted by compression stockings. OBJECTIVES: To test the hypotheses that, in nonobese subjects with CVI and OSA, wearing compression stockings during the day will attenuate OSA by reducing the amount of fluid displaced into the neck overnight. METHODS: Nonobese subjects with CVI and OSA were randomly assigned to 1 week of wearing compression stockings or to a 1-week control period without compression stockings, after which they crossed over to the other arm. Polysomnography and measurement of overnight changes in leg fluid volume and neck circumference were performed at baseline and at the end of compression stockings and control periods. MEASUREMENTS AND MAIN RESULTS: Twelve subjects participated. Compared with the end of the control period, at the end of the compression stockings period there was a 62% reduction in the overnight leg fluid volume change (P = 0.001) and a 60% reduction in the overnight neck circumference increase (P = 0.001) in association with a 36% reduction in the number of apneas and hypopneas per hour of sleep (from 48.4 ± 26.9 to 31.3 ± 20.2, P = 0.002). CONCLUSIONS: Redistribution of fluid from the legs into the neck at night contributes to the pathogenesis of OSA in subjects with CVI. Prevention of fluid accumulation in the legs during the day, and its nocturnal displacement into the neck, attenuates OSA in such subjects. [ABSTRACT FROM AUTHOR]

Competing Interests: Nil.

Importance: Pain is a common out-of-hospital symptom among patients, and opioids are often prescribed. Research suggests that overprescribing for acute traumatic pain is still prevalent, even when limits restricting opioid prescriptions have been implemented. Ketamine hydrochloride is an alternative to opioids in adults with out-of-hospital traumatic pain., Objective: To assess the noninferiority of intravenous ketamine compared with intravenous morphine sulfate to provide pain relief in adults with out-of-hospital traumatic pain., Design, Setting, and Participants: The Intravenous Subdissociative-Dose Ketamine Versus Morphine for Prehospital Analgesia (KETAMORPH) study was a multicenter, single-blind, noninferiority randomized clinical trial comparing ketamine hydrochloride (20 mg, followed by 10 mg every 5 minutes) with morphine sulfate (2 or 3 mg every 5 minutes) in adult patients with out-of-hospital trauma and a verbal pain score equal to or greater than 5. Enrollment occurred from November 23, 2017, to November 26, 2022, in 11 French out-of-hospital emergency medical units., Interventions: Patients were randomly assigned to ketamine (n = 128) or morphine (n = 123)., Main Outcomes and Measures: The primary outcome was the between-group difference in mean change in verbal rating scale pain scores measured from the time before administration of the study drug to 30 minutes later. A noninferiority margin of 1.3 was chosen., Results: A total of 251 patients were randomized (median age, 51 [IQR, 34-69] years; 111 women [44.9%] and 140 men [55.1%] among the 247 with data available) and were included in the intention-to-treat population. The mean pain score change was -3.7 (95% CI, -4.2 to -3.2) in the ketamine group compared with -3.8 (95% CI, -4.2 to -3.4) in the morphine group. The difference in mean pain score change was 0.1 (95% CI, -0.7 to 0.9) points. There were no clinically meaningful differences for vital signs between the 2 groups. The intravenous morphine group had 19 of 113 (16.8% [95% CI, 10.4%-25.0%]) adverse effects reported (most commonly nausea [12 of 113 (10.6%)]) compared with 49 of 120 (40.8% [95% CI, 32.0%-49.6%]) in the ketamine group (most commonly emergence phenomenon [24 of 120 (20.0%)]). No adverse events required intervention., Conclusions and Relevance: In the KETAMORPH study of patients with out-of-hospital traumatic pain, the use of intravenous ketamine compared with morphine showed noninferiority for pain reduction. In the ongoing opioid crisis, ketamine administered alone is an alternative to opioids in adults with out-of-hospital traumatic pain., Trial Registration: ClinicalTrials.gov Identifier: NCT03236805.

Plasmodesmata (PD) facilitate movement of molecules between plant cells. Regulation of this movement is still not understood. Plasmodesmata are hard to study, being deeply embedded within cell walls and incorporating several membrane types. Thus, structure and protein composition of PD remain enigmatic. Previous studies of PD protein composition identified protein lists with few validations, making functional conclusions difficult. We developed a PD scoring approach in iteration with large-scale systematic localization, defining a high-confidence PD proteome of Physcomitrium patens (HC300). HC300, together with bona fide PD proteins from literature, were placed in Pddb. About 65% of proteins in HC300 were not previously PD-localized. Callose-degrading glycolyl hydrolase family 17 (GHL17) is an abundant protein family with representatives across evolutionary scale. Among GHL17s, we exclusively found members of one phylogenetic clade with PD localization and orthologs occur only in species with developed PD. Phylogenetic comparison was expanded to xyloglucan endotransglucosylases/hydrolases and Exordium-like proteins, which also diversified into PD-localized and non-PD-localized members on distinct phylogenetic clades. Our high-confidence PD proteome HC300 provides insights into diversification of large protein families. Iterative and systematic large-scale localization across plant species strengthens the reliability of HC300 as basis for exploring structure, function, and evolution of this important organelle., (© 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation.)

Pseudomonas aeruginosa is one of the leading causes of healthcare-associated infections. For this study, the susceptibility profiles to antipseudomonal antibiotics and a quaternary ammonium compound, didecyldimethylammonium chloride (DDAC), widely used as a disinfectant, were established for 180 selected human and environmental hospital strains isolated between 2011 and 2020. Furthermore, a genomic study determined resistome and clonal putative relatedness for 77 of them. During the ten-year study period, it was estimated that 9.5% of patients' strains were resistant to carbapenems, 11.9% were multidrug-resistant (MDR), and 0.7% were extensively drug-resistant (XDR). Decreased susceptibility (DS) to DDAC was observed for 28.0% of strains, a phenotype significantly associated with MDR/XDR profiles and from hospital environmental samples (p < 0.0001). According to genomic analyses, the P. aeruginosa population unsusceptible to carbapenems and/or to DDAC was diverse but mainly belonged to top ten high-risk clones described worldwide by del Barrio-Tofiño et al. The carbapenem resistance appeared mainly due to the production of the VIM-2 carbapenemase (39.3%) and DS to DDAC mediated by MexAB-OprM pump efflux overexpression. This study highlights the diversity of MDR/XDR populations of P. aeruginosa which are unsusceptible to compounds that are widely used in medicine and hospital disinfection and are probably distributed in hospitals worldwide., (© 2023. The Author(s).)

Pseudomonas aeruginosa is one of the leading causes of healthcare-associated infections in humans. This bacterium is less represented in veterinary medicine, despite causing difficult-to-treat infections due to its capacity to acquire antimicrobial resistance, produce biofilms, and persist in the environment, along with its limited number of veterinary antibiotic therapies. Here, we explored susceptibility profiles to antibiotics and to didecyldimethylammonium chloride (DDAC), a quaternary ammonium widely used as a disinfectant, in 168 P. aeruginosa strains isolated from animals, mainly Equidae. A genomic study was performed on 41 of these strains to determine their serotype, sequence type (ST), relatedness, and resistome. Overall, 7.7% of animal strains were resistant to carbapenems, 10.1% presented a multidrug-resistant (MDR) profile, and 11.3% showed decreased susceptibility (DS) to DDAC. Genomic analyses revealed that the study population was diverse, and 4.9% were ST235, which is considered the most relevant human high-risk clone worldwide. This study found P. aeruginosa populations with carbapenem resistance, multidrug resistance, and DS to DDAC in equine and canine isolates. These strains, which are not susceptible to antibiotics used in veterinary and human medicine, warrant close the setting up of a clone monitoring, based on that already in place in human medicine, in a one-health approach.

Transition metals are essential for a wealth of metabolic reactions, but their concentrations need to be tightly controlled across cells and cell compartments, as metal excess or imbalance has deleterious effects. Metal homeostasis is achieved by a combination of metal transport across membranes and metal binding to a variety of molecules. Gene duplication is a key process in evolution, as emergence of advantageous mutations on one of the copies can confer a new function. Here, we report that the poplar genome contains two paralogues encoding NRAMP3 metal transporters localized in tandem. All Populus species analyzed had two copies of NRAMP3, whereas only one could be identified in Salix species indicating that duplication occurred when the two genera separated. Both copies are under purifying selection and encode functional transporters, as shown by expression in the yeast heterologous expression system. However, genetic complementation revealed that only one of the paralogues has retained the original function in release of metals stored in the vacuole previously characterized in A. thaliana. Confocal imaging showed that the other copy has acquired a distinct localization to the Trans Golgi Network (TGN). Expression in poplar suggested that the copy of NRAMP3 localized on the TGN has a novel function in the control of cell-to-cell transport of manganese. This work provides a clear case of neo-functionalization through change in the subcellular localization of a metal transporter as well as evidence for the involvement of the secretory pathway in cell-to-cell transport of manganese., (© The Author(s) 2022. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

The epidemiology of severe PAD, as characterized by short-distance intermittent claudication (IC) and chronic limb-threatening ischemia (CLTI), remains undefined in New Zealand (NZ). This was a retrospective observational cohort study of the Midland region in NZ, including all lower limb PAD-related surgical and percutaneous interventions between the 1st of January 2010 and the 31st of December 2021. Overall, 2541 patients were included. The mean annual incidence of short-distance IC was 15.8 per 100,000, and of CLTI was 36.2 per 100,000 population. The annual incidence of both conditions was greater in men. Women presented 3 years older with PAD (p < 0.001). Patients with short-distance IC had lower ipsilateral major limb amputation at 30 days compared to CLTI (IC 2, 0.3% vs. CLTI 298, 16.7%, p < 0.001). The 30-day mortality was greater in elderly patients (<65 years 2.7% vs. ≥65 years 4.4%, p = 0.049), but did not differ depending on sex (females 36, 3.7% vs. males 64, 4.1%, p = 0.787). Elderly age was associated with a worse survival for both short-distance IC and CLTI. There was a worse survival for females with CLTI. In conclusion, PAD imposes a significant burden in NZ, and further research is required in order to reduce this disparity.

Staphylococcus lugdunensis is a coagulase-negative Staphylococcus that emerges as an important opportunistic pathogen. However, little is known about the regulation underlying the transition from commensal to virulent state. Based on knowledge of S. aureus virulence, we suspected that the agr quorum sensing system may be an important determinant for the pathogenicity of S. lugdunensis . We investigated the functions of the transcriptional regulator AgrA using the agrA deletion mutant. AgrA played a role in cell pigmentation: Δ argA mutant colonies were white while the parental strains were slightly yellow. Compared with the wild-type strain, the Δ argA mutant was affected in its ability to form biofilm and was less able to survive in mice macrophages. Moreover, the growth of Δ agrA was significantly reduced by the addition of 10% NaCl or 0.4 mM H 2 O 2 and its survival after 2 h in the presence of 1 mM H 2 O 2 was more than 10-fold reduced. To explore the mechanisms involved beyond these phenotypes, the Δ agrA proteome and transcriptome were characterized by mass spectrometry and RNA-Seq. We found that AgrA controlled several virulence factors as well as stress-response factors, which are well correlated with the reduced resistance of the Δ agrA mutant to osmotic and oxidative stresses. These results were not the consequence of the deregulation of RNAIII of the agr system, since no phenotype or alteration of the proteomic profile has been observed for the ΔRNAIII mutant. Altogether, our results highlighted that the AgrA regulator of S. lugdunensis played a key role in its ability to become pathogenic. IMPORTANCE Although belonging to the natural human skin flora, Staphylococcus lugdunensis is recognized as a particularly aggressive and destructive pathogen. This study aimed to characterize the role of the response regulator AgrA, which is a component of the quorum-sensing agr system and known to be a major element in the regulation of pathogenicity and biofilm formation in Staphylococcus aureus. In the present study, we showed that, contrary to S. aureus, the agrA deletion mutant produced less biofilm. Inactivation of agrA conferred a white colony phenotype and impacted S. lugdunensis in its ability to survive in mice macrophages and to cope with osmotic and oxidative stresses. By global proteomic and transcriptomic approaches, we identified the AgrA regulon, bringing molecular bases underlying the observed phenotypes. Together, our data showed the importance of AgrA in the opportunistic pathogenic behavior of S. lugdunensis allowing it to be considered as an interesting therapeutic target.

The adherent-invasive Escherichia coli (AIEC) pathotype has been implicated in the pathogenesis of inflammatory bowel diseases in general and in Crohn's disease (CD) in particular. AIEC strains are primarily characterized by their ability to adhere to and invade intestinal epithelial cells. However, the genetic and phenotypic features of AIEC isolates vary greatly as a function of the strain's clonality, host factors, and the gut microenvironment. It is thus essential to identify the determinants of AIEC pathogenicity and understand their role in intestinal epithelial barrier dysfunction and inflammation. We reasoned that soil nematode Caenorhabditis elegans (a simple but powerful model of host-bacterium interactions) could be used to study the virulence of AIEC vs. non- AIEC E. coli strains. Indeed, we found that the colonization of C. elegans (strain N2) by E. coli impacted survival in a strain-specific manner. Moreover, the AIEC strains' ability to invade cells in vitro was linked to the median lifespan in C. elegans (strain PX627). However, neither the E. coli intrinsic invasiveness (i.e., the fact for an individual strain to be characterized as invasive or not) nor AIEC's virulence levels (i.e., the intensity of invasion, established in % from the infectious inoculum) in intestinal epithelial cells was correlated with C. elegans ' lifespan in the killing assay. Nevertheless, AIEC longevity of C. elegans might be a relevant model for screening anti-adhesion drugs and anti-invasive probiotics.

Background: Staphylococcus lugdunensis is a coagulase-negative Staphylococcus part of the commensal skin flora but emerge as an important opportunistic pathogen. Because iron limitation is a crucial stress during infectious process, we performed phenotypic study and compared proteomic profiles of this species incubated in absence and in presence of the iron chelator 2,2'-dipyridyl (DIP)., Results: No modification of cell morphology nor cell wall thickness were observed in presence of DIP. However iron-limitation condition promoted biofilm formation and reduced the ability to cope with oxidative stress (1 mM H 2 O 2 ). In addition, S. lugdunensis N920143 cultured with DIP was significantly less virulent in the larvae of Galleria mellonella model of infection than that grown under standard conditions. We verified that these phenotypes were due to an iron limitation by complementation experiments with FeSO 4 . By mass spectrometry after trypsin digestion, we characterized the first iron-limitation stress proteome in S. lugdunensis. Among 1426 proteins identified, 349 polypeptides were differentially expressed. 222 were more and 127 less abundant in S. lugdunensis incubated in iron-limitation condition, and by RT-qPCR, some of the corresponding genes have been shown to be transcriptionally regulated. Our data revealed that proteins involved in iron metabolism and carriers were over-expressed, as well as several ABC transporters and polypeptides linked to cell wall metabolism. Conversely, enzymes playing a role in the oxidative stress response (especially catalase) were repressed., Conclusions: This phenotypic and global proteomic study allowed characterization of the response of S. lugdunensis to iron-limitation. We showed that iron-limitation promoted biofilm formation, but decrease the oxidative stress resistance that may, at least in part, explained the reduced virulence of S. lugdunensis observed under low iron condition.

Nutrient recycling and mobilization from organ to organ all along the plant lifespan is essential for plant survival under changing environments. Nutrient remobilization to the seeds is also essential for good seed production. In this review, we summarize the recent advances made to understand how plants manage nutrient remobilization from senescing organs to sink tissues and what is the contribution of autophagy in this process. Plant engineering manipulating autophagy for better yield and plant tolerance to stresses will be presented., Competing Interests: The authors declare no conflict of interest.

An original immuno-regulatory strategy against inflammatory bowel diseases based on the use of 28 kDa glutathione S-transferase (P28GST), a unique schistosome protein, was recently proposed. Improvement of intestinal inflammation occurs through restoration of the immunological balance between pro-inflammatory T-helper 1 (Th1) responses and both T-helper 2 (Th2) and regulatory responses. However, detailed mechanisms explaining how P28GST prevents colitis and promotes gut homeostasis remain unknown. Considering the complex interplay between the adaptive and innate immune system and the intestinal microbiota, we raised the question of the possible role of the microbial ecosystem in the anti-inflammatory effects mediated by the helminth-derived P28GST protein. We first analyzed, by 16S rRNA sequencing, the bacterial profiles of mice fecal microbiota at several time points of the P28GST-immunomodulation period prior to trinitrobenzene sulfonic acid (TNBS)-colitis. The influence of gut microbiota in the P28GST-mediated anti-inflammatory effects was then assessed by fecal microbiota transplantation experiments from P28GST-immunized mice to either conventional or microbiota depleted naïve recipient mice. Finally, the experimental data were supplemented by the temporal fecal microbiota compositions of P28GST-treated Crohn's disease patients from a pilot clinical study (NCT02281916). The P28GST administration slightly modulated the diversity and composition of mouse fecal microbiota while it significantly reduced experimental colitis in mice. Fecal microbiota transplantation experiments failed to restore the P28GST-induced anti-inflammatory effects. In Crohn's disease patients, P28GST also induced slight changes in their overall fecal bacterial composition. Collectively, these results provide key elements in both the anti-inflammatory mechanisms and the safe therapeutic use of immunomodulation with such promising helminth-derived molecules., Competing Interests: None of the authors of this manuscript have a financial interest related to this work.

Micronutrient deficiencies affect a large part of the world's population. These deficiencies are mostly due to the consumption of grains with insufficient content of iron (Fe) or zinc (Zn). Both de novo uptake by roots and recycling from leaves may provide seeds with nutrients. Autophagy, which is a conserved mechanism for nutrient recycling in eukaryotes, was shown to be involved in nitrogen remobilization to seeds. Here, we have investigated the role of this mechanism in micronutrient translocation to seeds. We found that Arabidopsis thaliana plants impaired in autophagy display defects in nutrient remobilization to seeds. In the atg5-1 mutant, which is completely defective in autophagy, the efficiency of Fe translocation from vegetative organs to seeds was severely decreased even when Fe was provided during seed formation. Combining atg5-1 with the sid2 mutation that counteracts premature senescence associated with autophagy deficiency and using 57Fe pulse labeling, we propose a two-step mechanism in which Fe taken up de novo during seed formation is first accumulated in vegetative organs and subsequently remobilized to seeds. Finally, we show that translocation of Zn and manganese (Mn) to seeds is also dependent on autophagy. Fine-tuning autophagy during seed formation opens up new possibilities to improve micronutrient remobilization to seeds.

Histopathological diagnosis of biopsy samples and margin assessment of surgical specimens are challenging aspects in sarcoma. Using dog patient tissues, we assessed the performance of a recently developed technology for fast ex vivo molecular lipid-based diagnosis of sarcomas. The instrument is based on mass spectrometry (MS) molecular analysis through a laser microprobe operating under ambient conditions using excitation of endogenous water molecules. Classification models based on cancer/normal/necrotic, tumor grade, and subtypes showed a minimum of 97.63% correct classification. Specific markers of normal, cancer, and necrotic regions were identified by tandem MS and validated by MS imaging. Real-time detection capabilities were demonstrated by ex vivo analysis with direct interrogation of classification models., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Although iron is present in large amounts in the soil, its poor solubility means that plants have to use various strategies to facilitate its uptake. In this study, we show that expression of NtPDR3/NtABCG3, a Nicotiana tabacum plasma-membrane ABC transporter in the pleiotropic drug resistance (PDR) subfamily, is strongly induced in the root epidermis under iron deficiency conditions. Prevention of NtPDR3 expression resulted in N. tabacum plants that were less tolerant to iron-deficient conditions, displaying stronger chlorosis and slower growth than those of the wild-type when not supplied with iron. Metabolic profiling of roots and root exudates revealed that, upon iron deficiency, secretion of catechol-bearing O-methylated coumarins such as fraxetin, hydroxyfraxetin, and methoxyfraxetin to the rhizosphere was compromised in NtPDR3-silenced plants. However, exudation of flavins such as riboflavin was not markedly affected by NtPDR3-silencing. Expression of NtPDR3 in N. tabacum Bright Yellow-2 (BY-2) cells resulted in altered intra- and extracellular coumarin pools, supporting coumarin transport by this transporter. The results demonstrate that N. tabacum secretes both coumarins and flavins in response to iron deficiency and that NtPDR3 plays an essential role in the plant response to iron deficiency by mediating secretion of O-methylated coumarins to the rhizosphere.

Background: Acute pain is a common condition among prehospital patients and prompt management is pivotal. Opioids are the most frequently analgesics used in the prehospital setting. However, opioids are highly addictive, and some patients may develop opioid dependence, even when they are exposed to brief opioid treatments. Therefore, alternative non-opioid analgesia should be developed to manage pain in the prehospital setting. Used at subdissociative doses, ketamine, a noncompetitive N-methyl-D-aspartate and glutamate receptor antagonist, provides analgesic effects accompanied by preservation of protective airway reflexes. In this context, we will carry out a randomized controlled, open-label, multicenter trial to compare a subdissociative dose of ketamine to morphine to provide pain relief in the prehospital setting, in patients with traumatic and non-traumatic pain., Methods/design: This will be a multicenter, single-blind, randomized controlled trial. Consecutive adults will be enrolled in the prehospital setting if they experience moderate to severe, acute, non-traumatic and traumatic pain, defined as a numeric rating scale score greater or equal to 5. Patients will be randomized to receive ketamine or morphine by intravenous push. The primary outcome will be the between-group difference in mean change in numeric rating scale pain scores measured from the time before administration of the study medication to 30 min later., Discussion: This upcoming randomized clinical trial was design to assess the efficacy and safety of ketamine, an alternative non-opiate analgesia, to manage non-traumatic and traumatic pain in the prehospital setting. We aim to provide evidence to change prescribing practices to reduce exposition to opioids and the subsequent risk of addiction., Trial Registration: ClinicalTrials.gov, ID: NCT03236805 . Registered on 2 August 2017.

Ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) is the most abundant enzyme in plants and is responsible for CO 2 fixation during photosynthesis. This enzyme is assembled from eight large subunits (RbcL) encoded by a single chloroplast gene and eight small subunits (RbcS) encoded by a nuclear gene family. Rubisco is primarily found in the chloroplasts of mesophyll (C3 plants), bundle-sheath (C4 plants), and guard cells. In certain species, photosynthesis also takes place in the secretory cells of glandular trichomes, which are epidermal outgrowths (hairs) involved in the secretion of specialized metabolites. However, photosynthesis and, in particular, Rubisco have not been characterized in trichomes. Here, we show that tobacco ( Nicotiana tabacum ) trichomes contain a specific Rubisco small subunit, NtRbcS-T, which belongs to an uncharacterized phylogenetic cluster (T). This cluster contains RbcS from at least 33 species, including monocots, many of which are known to possess glandular trichomes. Cluster T is distinct from the cluster M, which includes the abundant, functionally characterized RbcS isoforms expressed in mesophyll or bundle-sheath cells. Expression of NtRbcS-T in Chlamydomonas reinhardtii and purification of the full Rubisco complex showed that this isoform conferred higher V max values as well as higher acidic pH-dependent activity than NtRbcS-M, an isoform expressed in the mesophyll. This observation was confirmed with trichome extracts. These data show that an ancient divergence allowed for the emergence of a so-far-uncharacterized RbcS cluster. We propose that secretory trichomes have a particular Rubisco uniquely adapted to secretory cells where CO K m values as well as higher acidic pH-dependent activity than NtRbcS-M, an isoform expressed in the mesophyll. This observation was confirmed with trichome extracts. These data show that an ancient divergence allowed for the emergence of a so-far-uncharacterized RbcS cluster. We propose that secretory trichomes have a particular Rubisco uniquely adapted to secretory cells where CO 2 is released by the active specialized metabolism., (© 2017 American Society of Plant Biologists. All Rights Reserved.)

Background: The purpose of this study was to describe the sleep structure (especially slow wave sleep) in adults with congenital central hypoventilation syndrome (CCHS), a rare genetic disease due to mutations in the PHOX2B gene. Fourteen patients aged 23 (19.0; 24.8) years old (median [1 rst -3rd quartiles]) with CCHS underwent a sleep interview and night-time attended polysomnography with their ventilatory support. Their sleep variables were compared to those collected in 15 healthy control subjects matched for age, sex and body mass index., Results: The latency to N3 sleep was shorter in patients (26.3 min [24.0; 30.1]) than in controls (49.5 min [34.3; 66.9]; P = 0.005), and sleep onset latency tended to be shorter in patients (14.0 min [7.0; 20.5]) than in controls (33.0 min [18.0; 49.0]; P = 0.052). Total sleep time, sleep stage percentages, sleep fragmentation as well as respiratory and movement index were within normal ranges and not different between groups., Conclusions: Normal sleep in adult patients with CCHS and adequate ventilator support indicates that the PHOX2 gene mutations do not affect brain sleep networks. Consequently, any complaint of disrupted sleep should prompt clinicians to look for the usual causes of sleep disorders, primarily inadequate mechanical ventilation. Shorter N3 latency may indicate a higher need for slow wave sleep, to compensate for the abnormal respiratory-related cortical activity during awake quiet breathing observed in patients with CCH.

Each essential transition metal plays a specific role in metabolic processes and has to be selectively transported. Living organisms need to discriminate between essential and non-essential metals such as cadmium (Cd(2+) ), which is highly toxic. However, transporters of the natural resistance-associated macrophage protein (NRAMP) family, which are involved in metal uptake and homeostasis, generally display poor selectivity towards divalent metal cations. In the present study we used a unique combination of yeast-based selection, electrophysiology on Xenopus oocytes and plant phenotyping to identify and characterize mutations that allow plant and mammalian NRAMP transporters to discriminate between their metal substrates. We took advantage of the increased Cd(2+) sensitivity of yeast expressing AtNRAMP4 to select mutations that decrease Cd(2+) sensitivity while maintaining the ability of AtNRAMP4 to transport Fe(2+) in a population of randomly mutagenized AtNRAMP4 cDNAs. The selection identified mutations in three residues. Among the selected mutations, several affect Zn(2+) transport, whereas only one, E401K, impairs Mn(2+) transport by AtNRAMP4. Introduction of the mutation F413I, located in a highly conserved domain, into the mammalian DMT1 transporter indicated that the importance of this residue in metal selectivity is conserved among NRAMP transporters from plant and animal kingdoms. Analyses of overexpressing plants showed that AtNRAMP4 affects the accumulation of metals in roots. Interestingly, the mutations selectively modify Cd(2+) and Zn(2+) accumulation without affecting Fe transport mediated by NRAMP4 in planta. This knowledge may be applicable for limiting Cd(2+) transport by other NRAMP transporters from animals or plants., (© 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.)

Cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. However, little data are available regarding the identification of Cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. To evaluate the prevalence of Cryptosporidiumspp. in fish from Lake Geneva (Lac Léman) in France, 41 entire fish and 100 fillets (cuts of fish flesh) were collected from fishery suppliers around the lake. Nested PCR using degenerate primers followed by sequence analysis was used. Five fish species were identified as potential hosts of Cryptosporidium: Salvelinus alpinus, Esox lucius, Coregonus lavaretus, Perca fluviatilis, and Rutilus rutilus. The presence of Cryptosporidium spp. was found in 15 out of 41 fish (37%), distributed as follows: 13 (87%) C. parvum, 1 (7%) C. molnari, and 1 (7%) mixed infection (C. parvum and C. molnari). C. molnari was identified in the stomach, while C. parvum was found in the stomach and intestine. C. molnari was also detected in 1 out of 100 analyzed fillets. In order to identify Cryptosporidium subtypes, sequencing of the highly polymorphic 60-kDa glycoprotein (gp60) was performed. Among the C. parvum positive samples, three gp60 subtypes were identified: IIaA15G2R1, IIaA16G2R1, and IIaA17G2R1. Histological examination confirmed the presence of potential developmental stages of C. parvum within digestive epithelial cells. These observations suggest that C. parvum is infecting fish, rather than being passively carried. Since C. parvum is a zoonotic species, fish potentially contaminated by the same subtypes found in terrestrial mammals would be an additional source of infection for humans and animals, and may also contribute to the contamination of the environment with this parasite. Moreover, the risk of human transmission is strengthened by the observation of edible fillet contamination.