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MicroRNAs (miRNAs) are small regulatory RNA molecules that inhibit the expression of specific target genes by binding to and cleaving their messenger RNAs or otherwise inhibiting their translation into proteins. miRNAs are transcribed as much larger primary transcripts (pri-miRNAs), the function of which is not fully understood. Here we show that plant pri-miRNAs contain short open reading frame sequences that encode regulatory peptides. The pri-miR171b of Medicago truncatula and the pri-miR165a of Arabidopsis thaliana produce peptides, which we term miPEP171b and miPEP165a, respectively, that enhance the accumulation of their corresponding mature miRNAs, resulting in downregulation of target genes involved in root development. The mechanism of miRNA-encoded peptide (miPEP) action involves increasing transcription of the pri-miRNA. Five other pri-miRNAs of A. thaliana and M. truncatula encode active miPEPs, suggesting that miPEPs are widespread throughout the plant kingdom. Synthetic miPEP171b and miPEP165a peptides applied to plants specifically trigger the accumulation of miR171b and miR165a, leading to reduction of lateral root development and stimulation of main root growth, respectively, suggesting that miPEPs might have agronomical applications.

Parts of the Brunn–Minkowski theory can be extended to hedgehogs, which are envelopes of families of affine hyperplanes parametrized by their Gauss map. F. Fillastre introduced Fuchsian convex bodies, which are the closed convex sets of Lorentz–Minkowski space that are globally invariant under the action of a Fuchsian group. In this paper, we undertake a study of plane Lorentzian and Fuchsian hedgehogs. In particular, we prove the Fuchsian analogues of classical geometrical inequalities (analogues that are reversed as compared to classical ones).

Ustilago maydis is a fungus infecting aerial parts of maize to form smutted galls. Due to its interest as a genetic tool in plant pathology, we evaluated its ability to penetrate into plant roots. The fungus can penetrate between epidermic root cells, forming inter and intracellular pseudohyphae. Root infection didn't provoke gall formation on the maize lines tested, and targeted PCR detection showed that U. maydis , unlike the other maize smut fungus Sporisorium reilianum , has a weak aptitude to grow from the roots up to the aerial part of maize. We also observed that U. maydis can infect Medicago truncatula hairy roots as an alternative host. This plant species is a model host to study root symbiosis, and this pathosystem can provide new insights on root–microbe interactions. Considering that U. maydis could be a soil fungus, we tested its responsiveness to GR24, a strigolactone analogue. Strigolactones are root exuded molecules which activate mitochondrial metabolism of arbuscular mycorrhizal (AM) fungi. Physiologic and molecular analysis revealed that GR24 also increases cell respiration of U. maydis . This result points out that strigolactones could have an incidence on several rhizospheric microbes. These data provide evidences that the biotrophic pathogen U. maydis has to be considered for studying root infection.

Introduction To improve the mortality rate on the battlefield, and especially the potentially survivable pre-Medical Treatment Facility deaths, Tactical Combat Casualty Care (TCCC) is now considered as a reference for management of combat casualty from the point of injury to the first medical treatment facility. TCCC comprises of a set of trauma management guidelines designed for use on the battlefield. The French Military Health Service also standardised a dedicated training programme, entitled “Sauvetage au Combat” (SC) (“ forward combat casualty care ”), with the characteristic of forward medicalisation on the battlefield, the medical team being projected as close as possible to the casualty at the point of injury. The aim of our article is to describe the process and the result of the SC training. Materials and methods Records from the French Military Health Service Academy – Ecole du Val-de-Grâce administration, head of the SC teaching programme, defining its guidelines, and supporting its structure and its execution, were examined and analyzed, since the standardisation of the SC training programme in 2008. The total number of trainees was listed following the different courses (SC1, SC2, SC3). Results At the end of 2013, every deployed combatant underwent SC1 courses (confidential data), 785 health-qualified combatants were graduated for SC2 courses and 672 Role 1 physician–nurse pairs for SC3 courses. Conclusion The SC concept and programmes were defined in France in 2007 and are now completely integrated into the predeployment training of all combatants but also of French Military Health Service providers. Finally, SC teaching programmes enhance the importance of teamwork in forward combat medicalisation settings.

Resume Il est conjecture depuis longtemps que si S est une surface convexe fermee de classe C + 2 dont les courbures principales K 1 , K 2 verifient l'inegalite ( K 1 − c )( K 2 − c )≤0 pour une constante c , alors S est une sphere. Des resultats partiels ont ete obtenus par A.D. Aleksandrov, H.F. Munzner et D. Koutroufiotis. Nous reformulons la conjecture en termes de herissons et nous donnons un contre-exemple. En outre, nous prouvons la conjecture pour les surfaces de largeur constante et donnons une nouvelle preuve pour les surfaces analytiques.

We previously reported the characterization of walls are thin1 (wat1), an Arabidopsis mutant that exhibits two developmental phenotypes in stems: (1) a severe decrease in fiber secondary cell wall thickness and (2) a reduction in stem height.1 Auxin concentration and transport were also significantly reduced in the stem base of wat1 plants. In the original study, these characteristics were observed in plants grown under short day conditions (9 h light/15 h dark). Herein, we provide evidence for partial phenotypic complementation of both wat1 developmental phenotypes when grown under a continuous light regime. Interestingly, when auxin concentration and basipetal transport were measured in these plants, neither was restored to wild-type levels. These results suggest that free auxin concentration is not responsible for the partial light-regulated complementation of wat1-mediated phenotypes.

Hedgehogs are a natural generalization of convex bodies of class C2+. After recalling some basic facts concerning this generalization, we use the notion of index to study differential and integral geometries of hedgehogs. As applications, we prove a particular case of the Tennis Ball Theorem and a property of normals to a plane convex body of constant width.

We present a partial extension of the Alexandrov-Fenchel inequality to hedgehogs (envelopes parametrized by their Gauss map), and we deduce a series of geometric inequalities for hedgehogs, one of which is an inequality of Brunn-Minkowski type. Finally, we present an application to the study of the Blaschke diagram.

Introduction Les hemorragies des zones frontieres entre le tronc et les membres sont non garrotables et difficilement compressibles. Ces hemorragies dites « jonctionnelles » sont actuellement responsables de 20 % des deces evitables de cause hemorragique sur le terrain, dont la majorite concerne la region de l’aine [1] . Pour y faire face, quatre dispositifs mecaniques permettant une compression proximale des axes arteriels ont ete recemment developpes. Peu d’etudes cliniques sont disponibles. L’objectif de notre etude etait de comparer l’efficacite de deux dispositifs : le Combat Ready Clamp ® (CRoC) et le SAM Junctional Tourniquet ® (SJT), appliques au creux inguinal lorsque les garrots tourniquets sont insuffisants en auto-application pour interrompre le flux arteriel. Materiel et methodes Nous avons realise une etude clinique prospective portant sur 84 volontaires sains, dont le protocole a ete approuve par le comite d’ethique de la recherche de l’HIA Desgenettes. Apres recueil du consentement eclaire et en l’absence de criteres d’exclusion, chaque volontaire etait reparti aleatoirement en deux groupes selon le dispositif utilise en complement d’un garrot tourniquet place a la racine de la cuisse. Tous les sujets participaient a l’etude en tenue de combat apres realisation d’un exercice physique. Le critere de jugement principal etait l’abolition complete du flux arteriel poplite mesure en echographie-doppler. Resultats Les resultats de notre etude montrent une tres bonne efficacite des dispositifs de compression inguinale CRoC et SJT, voisine de 90 %. Il n’y a pas de difference significative d’efficacite entre le CRoC et le SJT, qu’ils soient associes au garrot ou utilises seuls. En termes de douleur, les deux dispositifs jonctionnels ont une tolerance comparable, significativement bien meilleure que celle du garrot tourniquet. Meme si aucune correlation ne peut etre affirmee statistiquement, les deux dispositifs semblent plus difficiles a appliquer sur des sujets avec un IMC eleve et/ou un profil de pression arterielle plus eleve. Aucun effet indesirable n’a ete releve pendant l’etude, ni a l’issue ( Tableau 1 ). Discussion A efficacite semblable, nous pensons que le SJT presente des atouts par rapport au CRoC. Son temps de pose est significativement plus court, il rend possible une compression inguinale bilaterale, il est le seul dispositif de compression ayant egalement l’indication pour la stabilisation pelvienne. Enfin, le SJT est moins cher et moins lourd. Ces resultats concordent avec la seule etude clinique comparative retrouvee dans la litterature [2] . Notre etude apporte des arguments objectifs pour les travaux du comite technique d’enseignement du sauvetage au combat dont un des roles est de proposer les evolutions des materiels de sante. Ainsi, le SJT pourrait entrer dans la dotation des unites medicales operationnelles de Role 1, en remplacement du CRoC. Nous soulignons l’interet de ces dispositifs en prehospitalier pour le milieu civil.

Resume Introduction Capnocytophaga canimorsus est un fin bacille a Gram negatif, commensal de la gueule du chien et du chat, responsable chez l’homme d’une meningite aigue, habituellement febrile et severe, mais d’evolution favorable en l’absence de septicemie, dont l’incidence est tres faible. Observation Un homme de 60 ans a eu une meningite aigue febrile avec etat confusionnel. Le liquide cephalorachidien (LCR) contenait 4 000 leucocytes par mm 3 (83 % de polynucleaires neutrophiles), une hyperproteinorachie a 5,02 g/L et une glycorachie nulle ; l’examen direct a trouve un bacille a Gram negatif d’aspect inhabituel (incurve, fusiforme). L’evolution fut rapidement favorable grâce a une antibiotherapie maintenue 22 jours. L’identification bacteriologique se fit par sequencage du gene codant l’ARNr 16S a partir de la culture du LCR. Le patient etait accompagne du meme chien depuis 8 ans sans morsure recente. Commentaire Oriente par la notion d’un contact recent avec un chien ou un chat, d’autant plus qu’un bacille a Gram negatif est isole a l’examen direct du LCR, le diagnostic est confirme grâce a une mise en culture suffisamment prolongee du prelevement de LCR et/ou sanguin, avec au besoin identification moleculaire. La prevention de l’infection repose sur une antibiotherapie en cas de morsure profonde ou si la victime a un deficit immunitaire.

We give a characterization of convex hypersurfaces with an equichordal point in terms of hedgehogs of constant width.

Une nouvelle edition d’un ouvrage qui peut renforcer l’orthographe aussi bien chez les enfants que chez les adolescents et adultes. Ecrire correctement les mots d’usage releve essentiellement d’une bonne memoire – visuelle –, mais aussi de la connaissance d’un certain nombre de regles (comportant des exceptions) qui en facilitent l’apprentissage. Le classement et la presentation adoptes dans cet ouvrage ont ete etudies pour que l’observation attentive des mots entraine soit la memorisation soit la decouverte d’une regle applicable dans la plupart des cas. A la base du classement, l’alphabet phonetique, avec ses differentes ecritures et ses differentes positions dans le mot : « commencant par », « finissant par », « au milieu ». Chaque fiche-lecon s’ouvre sur des consignes qui orientent le lecteur vers ce qu’il doit decouvrir. Des exercices varies et ludiques sont concus pour la bonne integration et la verification des connaissances. Ils mettent en jeu, outre la reflexion et le sens logique, toutes les formes de memoire : visuelle, auditive et motrice. Date de premiere edition : 2004.

The plant hormone auxin (indole-3-acetic acid, IAA) has a crucial role in plant development. Its spatiotemporal distribution is controlled by a combination of biosynthetic, metabolic and transport mechanisms. Four families of auxin transporters have been identified that mediate transport across the plasma or endoplasmic reticulum membrane. Here we report the discovery and the functional characterization of the first vacuolar auxin transporter. We demonstrate that WALLS ARE THIN1 (WAT1), a plant-specific protein that dictates secondary cell wall thickness of wood fibres, facilitates auxin export from isolated Arabidopsis vacuoles in yeast and in Xenopus oocytes. We unambiguously identify IAA and related metabolites in isolated Arabidopsis vacuoles, suggesting a key role for the vacuole in intracellular auxin homoeostasis. Moreover, local auxin application onto wat1 mutant stems restores fibre cell wall thickness. Our study provides new insight into the complexity of auxin transport in plants and a means to dissect auxin function during fibre differentiation., The plant hormone auxin is essential for plant development and growth and is transported across cellular membranes via specialized transporter proteins. In this study, Ranocha et al. identify the first vacuolar auxin transporter, WAT1, suggesting an involvement of the vacuole in auxin signalling.

Hedgehogs are (possibly singular and self-intersecting) hypersurfaces that describe Minkowski differences of convex bodies in $$\mathbb {R}^{n+1}$$ . They are the natural geometrical objects when one seeks to extend parts of the Brunn–Minkowski theory to a vector space which contains convex bodies. In terms of characteristic functions, Minkowski addition of convex bodies correspond to convolution with respect to the Euler characteristic. In this paper, we extend this relationship to hedgehogs with an analytic support function. In this context, resorting only to the support functions and the Euler characteristic, we give various expressions for the index of a point with respect to a hedgehog.

Moesziomyces penicillariae (Brefield) Vanky is a basidiomycete fungus responsible for smut disease on pearl millet, an important staple food in the sub-Sahelian zone. We revisited the life cycle of this fungus. Unlike other Ustilaginales, mating of sporidia was never observed and monoclonal cultures of monokaryotic sporidia were infectious in the absence of mating with compatible partner. These data argued for an atypical monokaryotic diploid cell cycle of M. penicillariae , where teliospores only form solopathogenic sporidia. After inoculation of monoclonal solopathogenic strains on spikelets, the fungus infects the ovaries and induces the folding of the micropilar lips, as observed during early pollination steps. The infected embryo then becomes disorganized and the fungus invades peripheral ovary tissues before sporulating. We evaluated the systemic growth abilities of the fungus. After root inoculation, mycelium was observed around and inside the roots. As argued by transmission electron microscopy (TEM) observations and polymerase chain reaction (PCR) detection using specific primers for M. penicillariae , the fungus can grow from roots to the caulinar meristems. In spite of this systemic growth, no sori were formed on the varieties of pearl millet tested after root inoculation. All together, these data suggest that the reduced life cycle of M. penicillariae – i.e. dispersal of ‘ready to infect’ solopathogenic sporidia, floral infection – is an adaptation to the aetiology of this disease to short-cycle pearl millet varieties from the sub-Sahel.

International audience; The compatible interaction between the model plant, Arabidopsis thaliana, and the GMI1000 strain of the phytopathogenic bacterium, Ralstonia solanacearum, was investigated in an in vitro pathosystem. We describe the progression of the bacteria in the root from penetration at the root surface to the xylem vessels and the cell type-specific, cell wall-associated modifications that accompanies bacterial colonization. Within 6 days post inoculation, R. solanacearum provoked a rapid plasmolysis of the epidermal, cortical, and endodermal cells, including those not directly in contact with the bacteria. Plasmolysis was accompanied by a global degradation of pectic homogalacturonanes as shown by the loss of JIM7 and JIM5 antibody signal in the cell wall of these cell types. As indicated by immunolabeling with Rsol-I antibodies that specifically recognize R. solanacearum, the bacteria progresses through the root in a highly directed, centripetal manner to the xylem poles, without extensive multiplication in the intercellular spaces along its path. Entry into the vascular cylinder was facilitated by cell collapse of the two pericycle cells located at the xylem poles. Once the bacteria reached the xylem vessels, they multiplied abundantly and moved from vessel to vessel by digesting the pit membrane between adjacent vessels. The degradation of the secondary walls of xylem vessels was not a prerequisite for vessel colonization as LM10 antibodies strongly labeled xylem cell walls, even at very late stages in disease development. Finally, the capacity of R. solanacearum to specifically degrade certain cell wall components and not others could be correlated with the arsenal of cell wall hydrolytic enzymes identified in the bacterial genome.

Cinnamoyl-CoA reductase (CCR), which catalyses the first committed step of the lignin-specific branch of monolignol biosynthesis, has been extensively characterized in dicot species, but few data are available in monocots. By screening a Mu insertional mutant collection in maize, a mutant in the CCR1 gene was isolated named Zmccr1(-). In this mutant, CCR1 gene expression is reduced to 31% of the residual wild-type level. Zmccr1(-) exhibited enhanced digestibility without compromising plant growth and development. Lignin analysis revealed a slight decrease in lignin content and significant changes in lignin structure. p-Hydroxyphenyl units were strongly decreased and the syringyl/guaiacyl ratio was slightly increased. At the cellular level, alterations in lignin deposition were mainly observed in the walls of the sclerenchymatic fibre cells surrounding the vascular bundles. These cell walls showed little to no staining with phloroglucinol. These histochemical changes were accompanied by an increase in sclerenchyma surface area and an alteration in cell shape. In keeping with this cell type-specific phenotype, transcriptomics performed at an early stage of plant development revealed the down-regulation of genes specifically associated with fibre wall formation. To the present authors' knowledge, this is the first functional characterization of CCR1 in a grass species.

Il s'agit d'une version corrigée d'un précédent dépôt.; The classical Minkowski problem has a natural extension to hedgehogs, that is to Minkowski differences of closed convex hypersurfaces. This extended Minkowski problem is much more difficult since it essentially boils down to the question of solutions of certain Monge-Ampère equations of mixed type on the unit sphere. In this paper, we mainly consider the uniqueness question and give first results.

International audience; The chitin elicitor-binding protein (CEBiP) from rice was the first plant lysin motif (LysM) protein for which the biological and biochemical function had been established. It belongs to a plant-specific family of extracellular LysM proteins (LYMs) for which we analyzed the phylogeny. LYMs are present in vascular plants only, where an early gene duplication event might have resulted in two types which were retained in present day genomes. LYMs consist of a signal peptide, three consecutive LysMs, separated by cysteine pairs, and a C-terminal region without any known signature, whose length allows the distinction between the two types, and which may be followed by a glycosylphosphatidylinositol (GPI) anchor motif. We analyzed a representative of each type, MtLYM1 and MtLYM2, from Medicago truncatula at the biochemical level and with respect to their expression patterns and observed some similarities but also marked differences. MtLYM1 and MtLYM2 proved to be very different with regard to abundance and apparent molecular mass on SDS-PAGE. Both undergo several post-translational modifications, including N-glycosylation and the addition of a GPI anchor, which would position the proteins at the outer face of the plasma membrane. Only MtLYM2, but not MtLYM1, showed specific binding to biotinylated N-acetylchitooctaose in a manner similar to CEBiP, which belongs to the same type. We postulate that LYM2-type proteins likely function in the perception of chitin-related molecules, whereas possible functions of LYM1-type proteins remain to be elucidated.

Background Cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the final steps in the biosynthesis of monolignols, the monomeric units of the phenolic lignin polymers which confer rigidity, imperviousness and resistance to biodegradation to cell walls. We have previously shown that the Eucalyptus gunnii CCR and CAD2 promoters direct similar expression patterns in vascular tissues suggesting that monolignol production is controlled, at least in part, by the coordinated transcriptional regulation of these two genes. Although consensus motifs for MYB transcription factors occur in most gene promoters of the whole phenylpropanoid pathway, functional evidence for their contribution to promoter activity has only been demonstrated for a few of them. Here, in the lignin-specific branch, we studied the functional role of MYB elements as well as other cis-elements identified in the regulatory regions of EgCAD2 and EgCCR promoters, in the transcriptional activity of these gene promoters. Results By using promoter deletion analysis and in vivo footprinting, we identified an 80 bp regulatory region in the Eucalyptus gunnii EgCAD2 promoter that contains two MYB elements, each arranged in a distinct module with newly identified cis-elements. A directed mutagenesis approach was used to introduce block mutations in all putative cis-elements of the EgCAD2 promoter and in those of the 50 bp regulatory region previously delineated in the EgCCR promoter. We showed that the conserved MYB elements in EgCAD2 and EgCCR promoters are crucial both for the formation of DNA-protein complexes in EMSA experiments and for the transcriptional activation of EgCAD2 and EgCCR promoters in vascular tissues in planta. In addition, a new regulatory cis-element that modulates the balance between two DNA-protein complexes in vitro was found to be important for EgCAD2 expression in the cambial zone. Conclusions Our assignment of functional roles to the identified cis-elements clearly demonstrates the importance of MYB cis-elements in the transcriptional regulation of two genes of the lignin-specific pathway and support the hypothesis that MYB elements serve as a common means for the coordinated regulation of genes in the entire lignin biosynthetic pathway.

By combining Zinnia elegans in vitro tracheary element genomics with reverse genetics in Arabidopsis, we have identified a new upstream component of secondary wall formation in xylary and interfascicular fibers. Walls are thin 1 (WAT1), an Arabidopsis thaliana homolog of Medicago truncatula NODULIN 21 (MtN21), encodes a plant-specific, predicted integral membrane protein, and is a member of the plant drug/metabolite exporter (P-DME) family (transporter classification number: TC 2.A.7.3). Although WAT1 is ubiquitously expressed throughout the plant, its expression is preferentially associated with vascular tissues, including developing xylem vessels and fibers. WAT1:GFP fusion protein analysis demonstrated that WAT1 is localized to the tonoplast. Analysis of wat1 mutants revealed two cell wall-related phenotypes in stems: a defect in cell elongation, resulting in a dwarfed habit and little to no secondary cell walls in fibers. Secondary walls of vessel elements were unaffected by the mutation. The secondary wall phenotype was supported by comparative transcriptomic and metabolomic analyses of wat1 and wild-type stems, as many transcripts and metabolites involved in secondary wall formation were reduced in abundance. Unexpectedly, these experiments also revealed a modification in tryptophan (Trp) and auxin metabolism that might contribute to the wat1 phenotype. Together, our data demonstrate an essential role for the WAT1 tonoplast protein in the control of secondary cell wall formation in fibers.

We sought to determine whether online use of a beat-by-beat cardiovascular index, CARDEAN (Alpha-2, Lyon, France), modifies the incidence of patient movement during colonoscopy under anesthesia.Monitoring included an electrocardiogram, oscillometric and noninvasive beat-by-beat arterial blood pressure, O2 saturation, bispectral index (BIS), and CARDEAN. CARDEAN consists of beat-by-beat Finapres (Ohmeda, Madison, WI) combined with an algorithm that detects hypertension followed by tachycardia and produces an index scaled 0 to 100. The anesthesiologist was denied access to Finapres and CARDEAN. Propofol was adjusted to keep 40BIS60. Alfentanil 3.5 microg x kg(-1) was administered according to conventional signs (tachycardia, hypertension, and movement), unless the patient had signs of brady/apnea or Spo(2)95%. One hundred fifty-nine patients presenting for colonoscopy under propofol anesthesia were prospectively randomized to (i) control: no other intervention, or (ii) CARDEAN: in addition to conventional signs, an observer instructed the anesthesiologist to administer alfentanil when CARDEAN was60. The primary outcome was the number of observed movements.Data were analyzed in 146 patients (control: 75; CARDEAN: 71). The doses of propofol and alfentanil were similar in both groups. When BIS was60, movements were less frequent in the CARDEAN group (3.3 movements/100 min [2.3-4.8]) than in the control group (6.7 [5.3-8.5]) (odds ratio: 0.5 [0.32; 0.76], P = 0.001). During the first 10 minutes of the procedure, the incidence of movements was 38% and 59% in the CARDEAN and control groups, respectively (P = 0.04).With BIS60, CARDEAN-guided opioid administration is associated with a reduction of 51% of clinically unpredictable movements in unparalyzed patients undergoing colonoscopy. More studies are required to refine the role of CARDEAN in surgical settings.

International audience; Phoma macdonaldii, the causal agent of black stem disease of sunflower (Helianthus annuus),also attacks roots and collars of the plants, resulting in early death. Totally resistant lines do not exist for infection of the aerial parts, but tolerant lines have been characterised. This paper presents a study on colonisation of a partially resistant and a susceptible sunflower line by P. macdonaldii. The fungus was transformed with a constitutively expressed reporter gene encoding the jellyfish green fluorescent protein via Agrobacterium tumefaciens, and colonisation of sunflower roots by this transformed strain was studied by various microscopy techniques including confocaland scanning electron microscopy. The results show that penetration of the fungus into the root occurred through natural fissures or through the epidermis andwas similar in both lines. In contrast, the colonisation rate of the stele was reduced in the partially resistant line, and the morphology of the fungal hyphae was also affected. The effect on hyphal morphology wasstrongest in the stele, indicating a localised production of defence compounds in this line.

cited By 17; International audience; To better understand the genetic control of secondary xylem formation in trees we analysed genes expressed during Eucalyptus xylem development. • Using eucalyptus xylem cDNA libraries, we identified EgROP1, a member of the plant ROP family of Rho-like GTPases. These signalling proteins are central regulators of many important processes in plants, but information on their role in xylogenesis is scarce. • Quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) confirmed that EgROP1 was preferentially expressed in the cambial zone and differentiating xylem in eucalyptus. Genetic mapping performed in a eucalyptus breeding population established a link between EgROP1 sequence polymorphisms and quantitative trait loci (QTLs) related to lignin profiles and fibre morphology. Overexpression of various forms of EgROP1 in Arabidopsis thaliana altered anisotropic cell growth in transgenic leaves, but most importantly affected vessel element and fibre growth in secondary xylem. Patches of fibre-like cells in the secondary xylem of transgenic plants showed changes in secondary cell wall thickness, lignin and xylan composition. • These results suggest a role for EgROP1 in fibre cell morphology and secondary cell wall formation making it a good candidate gene for marker-based selection of eucalyptus trees.

Chitin is an essential component of fungal cell walls, where it forms a crystalline scaffold, and chitooligosaccharides derived from it are signaling molecules recognized by the hosts of pathogenic fungi. Oomycetes are cellulosic fungus-like microorganisms which most often lack chitin in their cell walls. Here we present the first study of the cell wall of the oomyceteAphanomyces euteiches, a major parasite of legume plants. Biochemical analyses demonstrated the presence of ca. 10%N-acetyl-d-glucosamine (GlcNAc) in the cell wall. Further characterization of the GlcNAc-containing material revealed that it corresponds to noncrystalline chitosaccharides associated with glucans, rather than to chitin per se. Two putative chitin synthase (CHS) genes were identified by data mining of anA. euteichesexpressed sequence tag collection and Southern blot analysis, and full-length cDNA sequences of both genes were obtained. Phylogeny analysis indicated that oomycete CHS diversification occurred before the divergence of the major oomycete lineages. Remarkably, lectin labeling showed that theAphanomyces euteicheschitosaccharides are exposed at the cell wall surface, and study of the effect of the CHS inhibitor nikkomycin Z demonstrated that they are involved in cell wall function. These data open new perspectives for the development of antioomycete drugs and further studies of the molecular mechanisms involved in the recognition of pathogenic oomycetes by the host plants.

We prove a Sturm-type comparison theorem by a geometric study of plane (multi)hedgehogs. This theorem implies that for every $2\pi$-periodic smooth real function $h$, the number of zeros of $h$ in $[0,2\pi[$ is not bigger than the number of zeros of $h+h^{\prime\prime}$ plus $2$. In terms of $N$-hedgehogs, it can be interpreted as a comparison theorem between number of singularities and maximal number of support lines through a point. The rest of the paper is devoted to a series of geometric consequences.

Unexpected intraoperative movement may be detrimental during delicate surgery. This study tested retrospectively an algorithm based on beat-by-beat circulatory variables (incorporated into a Cardiovascular depth of anesthesia index: CARDEAN in relationship to unexpected movement, and compared its performance to that of the electroencephalogram (EEG)-derived index: BIS-XP 4.0.40 ASA I or II patients presenting for knee surgery had EEG (BIS XP 4.0), beat-by-beat (Finapres) finger non-invasive blood pressure (BP), conventional brachial BP and electrocardiogram (EKG) monitors attached. Anesthesia was induced and maintained with propofol and remifentanil. Before incision, the propofol concentration was set to maintain BIS60. From incision to emergence, the anesthesiologist was denied access to BIS or Finapres. Anesthesia adjustment was titrated at the discretion of the anesthesiologist according to conventional signs only: brachial BP, EKG, eyelash reflex, movement. Occurrences of movement and eye signs (divergence of eyeballs, tears, corneal reflex, eyelash reflex) were observed. The CARDEAN algorithm was written retrospectively and tested vs. BIS.11 movements occurred in 8 patients. CARDEAN60 predicted movement in 30% of the cases, 15 to 274 s before movement (sensitivity: 100%, specificity: 95%; relative operating curve ROC = 0.98; prediction probability pk = 0.98). BIS60 predicted movement in 19% of cases (sensitivity: 64%; specificity: 94%, ROC: 0.85, pk: 0.85).Retrospectively, a cardiovascular index predicted unexpected intraoperative movements. Prospective validation is needed.

The cellulose binding elicitor lectin (CBEL) from Phytophthora parasitica nicotianae contains two cellulose binding domains (CBDs) belonging to the Carbohydrate Binding Module1 family, which is found almost exclusively in fungi. The mechanism by which CBEL is perceived by the host plant remains unknown. The role of CBDs in eliciting activity was investigated using modified versions of the protein produced in Escherichia coli or synthesized in planta through the potato virus X expression system. Recombinant CBEL produced by E. coli elicited necrotic lesions and defense gene expression when injected into tobacco (Nicotiana tabacum) leaves. CBEL production in planta induced necrosis. Site-directed mutagenesis on aromatic amino acid residues located within the CBDs as well as leaf infiltration assays using mutated and truncated recombinant proteins confirmed the importance of intact CBDs to induce defense responses. Tobacco and Arabidopsis thaliana leaf infiltration assays using synthetic peptides showed that the CBDs of CBEL are essential and sufficient to stimulate defense responses. Moreover, CBEL elicits a transient variation of cytosolic calcium levels in tobacco cells but not in protoplasts. These results define CBDs as a novel class of molecular patterns in oomycetes that are targeted by the innate immune system of plants and might act through interaction with the cell wall.

Capnocytophaga canimorsus is a fusiform and filamentous gram-negative rod, part of the normal oral flora of dogs and cause rare human febrile acute meningitis, usually severe but curable.A sixty years old man presented a severe acute meningitis with fever and confusion. CSF show 4,000 cells/mm3 with 83% neutrophilis, increased protein level (5,02 g/L), very low glucose and positive Gram stain result. The patient fully and quickly recovered with antibiotherapy for 22 days. Bacteriological diagnosis was made by genomic study from CSF culture. The patient has a close contact with his dog without being recently bitten.Diagnosis, suggested by bites or contact with dog or cat, gram-negative bacilli with gram stain of CSF specimen, is possible by prolonged culture of CSF or blood sample, with if necessary genomic study. Antibioprophylaxis is strongly recommended in cases of deep bite wounds and for immunocompromised patients.

An extensive search for maize (Zea mays) genes involved in cell wall biosynthesis and assembly has been performed and 735 sequences have been centralized in a database, MAIZEWALL (http://www.polebio.scsv.ups-tlse.fr/MAIZEWALL). MAIZEWALL contains a bioinformatic analysis for each entry and gene expression data that are accessible via a user-friendly interface. A maize cell wall macroarray composed of a gene-specific tag for each entry was also constructed to monitor global cell wall-related gene expression in different organs and during internode development. By using this macroarray, we identified sets of genes that exhibit organ and internode-stage preferential expression profiles. These data provide a comprehensive fingerprint of cell wall-related gene expression throughout the maize plant. Moreover, an in-depth examination of genes involved in lignin biosynthesis coupled to biochemical and cytological data from different organs and stages of internode development has also been undertaken. These results allow us to trace spatially and developmentally regulated, putative preferential routes of monolignol biosynthesis involving specific gene family members and suggest that, although all of the gene families of the currently accepted monolignol biosynthetic pathway are conserved in maize, there are subtle differences in family size and a high degree of complexity in spatial expression patterns. These differences are in keeping with the diversity of lignified cell types throughout the maize plant.

The aim of this paper is to motivate the development of a Brunn-Minkowski theory for minimal surfaces. In 1988, H. Rosenberg and E. Toubiana studied a sum operation for finite total curvature complete minimal surfaces in $\mathbb{R}^{3}$ and noticed that minimal hedgehogs of $\mathbb{R}^{3} $ constitute a real vector space [14]. In 1996, the author noticed that the square root of the area of minimal hedgehogs of $\mathbb{R}^{3}$ that are modelled on the closure of a connected open subset of $\mathbb{S}^{2}$ is a convex function of the support function [5]. In this paper, the author ¶ (i) gives new geometric inequalities for minimal surfaces of $\mathbb{R}^{3}$; ¶ (ii) studies the relation between support functions and Enneper-Weierstrass representations; ¶ (iii) introduces and studies a new type of addition for minimal surfaces; ¶ (iv) extends notions and techniques from the classical Brunn-Minkowski theory to minimal surfaces. Two characterizations of the catenoid among minimal hedgehogs are given.

CLPG1, an endopolygalacturonase (endoPG) gene of Colletotrichum lindemuthianum, was transferred to tobacco (Nicotiana tabacum) leaves by using the Agrobacterium tumefaciens transient delivery system. The following four constructs were prepared:CLPG1, with or without its signal peptide (SP; PG1, PG1ΔSP); CLPG1 with the tobaccoexpansin1 SP instead of its own SP (Exp::PG1ΔSP); and a mutated version of the latter on two amino acids potentially involved in the catalytic site of CLPG1 (D202N/D203N). Chlorotic and necrotic lesions appeared 5 to 7 d postinfiltration, exclusively in response to CLPG1 fused to the expansin SP. The lesions were correlated to the production of an active enzyme. Necrosis-inducing activity, as well as endoPG activity, were completely abolished by site-directed mutagenesis. Ultrastructural immunocytolocalization experiments indicated that the expansin SP addressed CLPG1 to the cell wall. Staining of parenchyma cells revealed the progressive degradation of pectic material in junction zones and middle lamella as a function of time after infiltration, ultimately leading to cell separation. A 30% decrease in the GalUA content of the cell walls was simultaneously recorded, thereby confirming the hydrolytic effect of CLPG1 on pectic polysaccharides, in planta. The elicitor activity of CLPG1 was further illustrated by the induction of defense responses comprising active oxygen species and β-1,3-glucanase activity, before leaf necrosis. Altogether, the data demonstrate that an appropriate SP and a functional catalytic site are required for the proper expression and elicitor activity of the fungal endoPG CLPG1 in tobacco.

(1996). A Note on the Tennis Ball Theorem. The American Mathematical Monthly: Vol. 103, No. 4, pp. 338-340.

Let R be a continuous real function on the unit sphere S n of (n+1)-dimensional Euclidean space R n+1. We prove that the map h: S n → R , p↦∫ S n |〈p, q〉| R(q) dσ(q), where 〈·, ·〉 is the standard inner product and σ the spherical Lebesgue measure, is of class C2. It follows that the boundaries of zonoids (resp. generalized zonoids), whose generating measure have a continuous density with respect to σ, can be considered as hedgehogs (envelopes parametrized by their Gauss map) with a C2 support function. We deduce a local property for such zonoids. We give a formula for the curvature function of the hedgehog defined by h and we deduce a necessary and sufficient condition for h being the support function of a convex body of class C2+. We define projection hedgehogs (resp. mixed projection hedgehogs) and interpret their support functions in terms of n-dimensional volume (resp. mixed volume). Finally, we consider the extension of the classical Minkowski problem to hedgehogs.

Background Nitrogen (N) is a main nutrient required for tree growth and biomass accumulation. In this study, we analyzed the effects of contrasting nitrogen fertilization treatments on the phenotypes of fast growing Eucalyptus hybrids (E. urophylla x E. grandis) with a special focus on xylem secondary cell walls and global gene expression patterns. Results Histological observations of the xylem secondary cell walls further confirmed by chemical analyses showed that lignin was reduced by luxuriant fertilization, whereas a consistent lignin deposition was observed in trees grown in N-limiting conditions. Also, the syringyl/guaiacyl (S/G) ratio was significantly lower in luxuriant nitrogen samples. Deep sequencing RNAseq analyses allowed us to identify a high number of differentially expressed genes (1,469) between contrasting N treatments. This number is dramatically higher than those obtained in similar studies performed in poplar but using microarrays. Remarkably, all the genes involved the general phenylpropanoid metabolism and lignin pathway were found to be down-regulated in response to high N availability. These findings further confirmed by RT-qPCR are in agreement with the reduced amount of lignin in xylem secondary cell walls of these plants. Conclusions This work enabled us to identify, at the whole genome level, xylem genes differentially regulated by N availability, some of which are involved in the environmental control of xylogenesis. It further illustrates that N fertilization can be used to alter the quantity and quality of lignocellulosic biomass in Eucalyptus, offering exciting prospects for the pulp and paper industry and for the use of short coppices plantations to produce second generation biofuels. Electronic supplementary material The online version of this article (doi:10.1186/s12870-014-0256-9) contains supplementary material, which is available to authorized users.

Background Eucalyptus species are the most widely planted hardwood trees in the world representing more than 4.75 million ha in Brazil. Their high productivity, valuable wood properties and wide adaptability could allow sustainable and cost-efficient production of lignocellulosic bioenergy. The main limitation to this objective is wood recalcitrance to degradation which is linked to the structure and composition of lignified secondary cell walls. Lignin, for example, impairs the accessibility of cellulose during kraft pulping as well as during saccharification, a key step of bioethanol production. The application of nitrogen fertilizers is one strategy to increase growth rates and productivity since nitrogen is one of the most limiting nutrient for tree growth and carbon sequestration. However, the effects of nitrogen availability on wood properties and related gene expression are poorly understood. In poplar, it was recently reported that N fertilization increased aerial biomass, while in wood, fibre morphology and secondary cell wall structure and composition were modified. An increase in cellulose coupled with a decrease in lignin was observed and the mRNA profiles evaluated by microarray showed that nitrogen and tension wood have overlapping effects [1]. Moreover, a highly significant genetic correlation was observed between plant growth and lignin/cellulose composition. Quantitative trait loci co-localization identified the genomic position of potential pleiotropic regulators [2]. In order to get an insight on the regulation of nitrogen availability on wood formation in Eucalyptus, we have studied the effects of nitrogen fertilization on xylem transcriptome profiles using RNA-seq technology.

L’introduction de la notion de vecteurs en classe de seconde est, aux dires des professeurs expérimentés, l'un des chapitres les plus difficiles de la classe de seconde et le moins facilement compris des élèves. L'objectif de ce mémoire est d’essayer de répondre à la problématique suivante : d’où viennent les difficultés des élèves dans le calcul vectoriel ? Comment faire en sorte que les élèves maîtrisent au mieux le calcul vectoriel ? Le mémoire présente ainsi dans une première partie une fiche de lecture de l'article « Les vecteurs à l'issue de la seconde. Une analyse des manuels et de quelques difficultés d'élèves » de Marilena Bittar (« Petit x », 2000). La date de parution de cet article offre une perspective historique intéressante sur une problématique qui est aussi ancienne que l'enseignement des vecteurs et permet des comparaisons avec l'approche actuelle imposée par les programmes. Dans une deuxième partie, le mémoire rappelle le contenu du programme actuel de seconde sur le calcul vectoriel et fait quelques remarques à son sujet. Dans un troisième temps, il décrit et analyse quelques extraits de traces écrites de nos élèves pour comprendre d'où viennent leurs difficultés. Des exercices de manuels sont également étudiés. Finalement, avant de conclure, le mémoire propose des pistes permettant de faciliter l'apprentissage et la maîtrise du calcul vectoriel par les élèves.

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