The association between Dioscorea sansibarensis and Orrella dioscoreae as a model for hereditary leaf symbiosis

Hereditary, or vertically-transmitted, symbioses affect a large number of animal species and some plants. The precise mechanisms underlying transmission of functions of these associations are often difficult to describe, due to the difficulty in separating the symbiotic partners. This is especially the case for plant-bacteria hereditary symbioses, which lack experimentally tractable model systems. Here, we demonstrate the potential of the leaf symbiosis between the wild yam Dioscorea sansibarensis and the bacterium Orrella dioscoreae (O. dioscoreae) as a model system for hereditary symbiosis. O. dioscoreae is easy to grow and genetically manipulate, which is unusual for hereditary symbionts. These properties allowed us to design an effective antimicrobial treatment to rid plants of bacteria and generate whole aposymbiotic plants, which can later be re-inoculated with bacterial cultures. Aposymbiotic plants did not differ morphologically from symbiotic plants and the leaf forerunner tip containing the symbiotic glands formed normally even in the absence of bacteria, but microscopic differences between symbiotic and aposymbiotic glands highlight the influence of bacteria on the development of trichomes and secretion of mucilage. This is to our knowledge the first leaf symbiosis where both host and symbiont can be grown separately and where the symbiont can be genetically altered and reintroduced to the host.

Structures and roles of BcsD and partner scaffold proteins in proteobacterial cellulose secretion

Cellulose is the world's most abundant biopolymer, and similar to its role as a cell wall component in plants, it is a prevalent constituent of the extracellular matrix in bacterial biofilms. Although bacterial cellulose (BC) was first described in the 19th century, it was only recently revealed that it is produced by several distinct types of Bcs secretion systems that feature multiple accessory subunits in addition to a catalytic BcsAB synthase tandem. We recently showed that crystalline cellulose secretion in the Gluconacetobacter genus (α-Proteobacteria) is driven by a supramolecular BcsH-BcsD scaffold-the "cortical belt"-which stabilizes the synthase nanoarrays through an unexpected inside-out mechanism for secretion system assembly. Interestingly, while bcsH is specific for Gluconacetobacter, bcsD homologs are widespread in Proteobacteria. Here, we examine BcsD homologs and their gene neighborhoods from several plant-colonizing β- and γ-Proteobacteria proposed to secrete a variety of non-crystalline and/or chemically modified cellulosic polymers. We provide structural and mechanistic evidence that through different quaternary structure assemblies BcsD acts with proline-rich BcsH, BcsP, or BcsO partners across the proteobacterial clade to form synthase-interacting intracellular scaffolds that, in turn, determine the biofilm strength and architecture in species with strikingly different physiology and secreted biopolymers.

DNA demethylation and hypermethylation are both required for late nodule development in Medicago

Plant epigenetic regulations are involved in transposable element silencing, developmental processes and responses to the environment^1-7. They often involve modifications of DNA methylation, particularly through the DEMETER (DME) demethylase family and RNA-dependent DNA methylation (RdDM)⁸. Root nodules host rhizobia that can fix atmospheric nitrogen for the plant's benefit in nitrogen-poor soils. The development of indeterminate nodules, as in Medicago truncatula, involves successive waves of gene activation^9-12, control of which raises interesting questions. Using laser capture microdissection (LCM) coupled to RNA-sequencing (SYMbiMICS data¹¹), we previously identified 4,309 genes (termed NDD) activated in the nodule differentiation and nitrogen fixation zones, 36% of which belong to co-regulated genomic regions dubbed symbiotic islands¹³. We found MtDME to be upregulated in the differentiation zone and required for nodule development, and we identified 474 differentially methylated regions hypomethylated in the nodule by analysing ~2% of the genome⁴. Here, we coupled LCM and whole-genome bisulfite sequencing for a comprehensive view of DNA methylation, integrated with gene expression at the tissue level. Furthermore, using CRISPR-Cas9 mutagenesis of MtDRM2, we showed the importance of RdDM for CHH hypermethylation and nodule development. We thus proposed a model of DNA methylation dynamics during nodule development.

MtEFD and MtEFD2: Two transcription factors with distinct neofunctionalization in symbiotic nodule development

Rhizobium-legume nitrogen-fixing symbiosis involves the formation of a specific organ, the root nodule, which provides bacteria with the proper cellular environment for atmospheric nitrogen fixation. Coordinated differentiation of plant and bacterial cells is an essential step of nodule development, for which few transcriptional regulators have been characterized. Medicago truncatula ETHYLENE RESPONSE FACTOR REQUIRED FOR NODULE DIFFERENTIATION (MtEFD) encodes an APETALA2/ETHYLENE RESPONSIVE FACTOR (ERF) transcription factor, the mutation of which leads to both hypernodulation and severe defects in nodule development. MtEFD positively controls a negative regulator of cytokinin signaling, the RESPONSE REGULATOR 4 (MtRR4) gene. Here we showed that that the Mtefd-1 mutation affects both plant and bacterial endoreduplication in nodules, as well as the expression of hundreds of genes in young and mature nodules, upstream of known regulators of symbiotic differentiation. MtRR4 expressed with the MtEFD promoter complemented Mtefd-1 hypernodulation but not the nodule differentiation phenotype. Unexpectedly, a nonlegume homolog of MtEFD, AtERF003 in Arabidopsis (Arabidopsis thaliana), could efficiently complement both phenotypes of Mtefd-1, in contrast to the MtEFD paralog MtEFD2 expressed in the root and nodule meristematic zone. A domain swap experiment showed that MtEFD2 differs from MtEFD by its C-terminal fraction outside the DNA binding domain. Furthermore, clustered regularly interspaced short palindromic repeats-CRISPR associated protein 9 (CRISPR-Cas9) mutagenesis of MtEFD2 led to a reduction in the number of nodules formed in Mtefd-1, with downregulation of a set of genes, including notably NUCLEAR FACTOR-YA1 (MtNF-YA1) and MtNF-YB16, which are essential for nodule meristem establishment. We, therefore, conclude that nitrogen-fixing symbiosis recruited two proteins originally expressed in roots, MtEFD and MtEFD2, with distinct functions and neofunctionalization processes for each of them.

How to identify the anterior cribriform plate in the medial approach to the frontal sinus

Draf III frontal sinusotomy is one of the most complex surgical procedures on the frontal sinus, designed to limit the risks of restenosis by ensuring unification of the two ostia and resection of the floor of the sinus. This procedure requires a good knowledge of anatomy and sufficient surgical expertise to avoid the risk of CSF leak and to limit the risk of restenosis. The surgeon can use various landmarks, consisting of foramina, bone grooves and arteries located on the anterior part of the cribriform plate to guide the procedure. The purpose of this technical note is to explain the use of these landmarks to ensure safe Draf III frontal sinusotomy via a medial approach.

The French Cochlear Implant Registry (EPIIC): General indicators

Cochlear and brainstem implants have been included on the list of reimbursable products (LPPR) in France since March of 2009. The implants were initially inscribed for 5 years, after which an application for renewal with the French National Commission for the Evaluation of Medical Devices and Health Technologies (Commission Nationale d'évaluation des dispositifs médicaux et des technologies de santé - CNEDiMTS) was required [Haute Autorité de santé, 2009]. Upon registration to the list of reimbursable products, the companies and the reference centers for cochlear and brainstem implants were asked to set up a post-registration registry called EPIIC. This article reports the evolution in the EPIIC registry of the general indicators for 5051 patients over the five years from 2012-2016.

The French Cochlear Implant Registry (EPIIC): Cochlear implantation complications

OBJECTIVES

The aim of this study was to evaluate peri- and post-operative complications related to cochlear implantations. We searched for risk factors predicting these complications and analyzed the complications in the youngest and most elderly.

STUDY DESIGN

Retrospective analysis of cochlear implant patients.

MATERIALS AND METHODS

All patients who underwent cochlear implantation in France between January 2012 and December 2016 were anonymized and registered in the EPIIC database. This population included 3483 adults and 2245 children. Their demographic and surgical data and their incidence of peri- or post-operative complications, including their severity, whether major or minor, were all indicated.

RESULTS

The global complication rate was 6.84%. The risk of complication was higher in initial implantation versus reimplantation (P<0.0001). The risk was also higher for bilateral implantation versus unilateral (P<0.0001). Complications were more frequent for patients with cochlear malformation (P=0.002). There was no difference in complication rates across age groups; babies under 1 year old, and the elderly over 80 and even over 90, did not have more complications than the rest of the population. Patients treated in the daily care unit had no more complications than those who were hospitalized for one night or more (P=0.64).

CONCLUSION

Cochlear implantation is a safe technique with a low incidence of complications. The absence of increased risk in patients at the extremes of the age spectrum justifies offering this solution to all, without age limitation.

The French Cochlear Implant Registry (EPIIC): Perception and language results in infants with cochlear implantation under the age of 24 months

OBJECTIVE

Multi-centre study of the National French Registry (EPIIC) of patients with cochlear implants, focusing on infants who were operated-on under the age of 24 months between 2012 and 2016.

PATIENTS AND METHODS

A total of 615 profoundly deaf infants, who received cochlear implants (CIs) before their second birthday, were included in the registry by different CI centers. Epidemiological, surgical, speech therapy and school, follow-up data were included in the registry, 12, 24, 36 and 48 months thereafter. The following parameters were studied: type of implantation (uni- or bilateral), complications, cause of deafness, category of auditory perception (CAP), Open-set word recognition score (OSW), speech intelligibility rating, lexical comprehension with EVIP (Peabody), communication mode and type of schooling. Bilateral simultaneous CI (BiCI) and unilateral CI (UniCI) groups were compared.

RESULTS

There were 744 implantations. The explantation-reimplantation rate, within the four-year follow-up, was just 3.6%. Mean implantation age was 16.0 months, and similar in the two groups (BiCI/UniCI). A total of 51% of children had their first implant between 12 and 18 months, and 15% before 12 months. Implantation was unilateral in 52% of cases. Fifty-six percent of the bilateral procedures were sequential, with a mean delay of 16.8 months for the second implantation. The cause of deafness was unknown in 52% of cases. Of the 48% (297/615) of attributed cases, 32% had clear genetic causes. The remaining deafness was due to cytomegalovirus (CMV, 8%), inner-ear malformation (5%) and meningitis (3%). The main complications were from infections (47%) and internal device failure (25%). Four years post-operation, 84% of the UniCI and 75% of BiCl groups had a CAP≥5, and 83% of UniCl and 100% BiCI had OSW≥80%. Furthermore 74% of UniCI and 77% of BiCI communicated orally and 85% of UniCI and 90% of BiCI integrated into mainstream schooling.

CONCLUSION

The French Registry of cochlear implants (EPIIC) is the only such national registry in the world. Our analysis illustrates the immediate benefits of, either single or double, cochlear implantation for language, perception skills and schooling.

The French National Cochlear Implant Registry (EPIIC): Cochlear explantation and reimplantation

This study aims to determine the frequency and causes of cochlear explants with re-implantation (ERI) after 5 years' follow up of the patients included in the French national EPIIC (étude post-inscription des implants cochléaires) registry tracking patients with cochlear implantation. This multicenter, descriptive prospective study was conducted on 5051 patients enrolled in the EPIIC database between January 2012 and December 2016. Ninety-five patients (1.9%) received a primary implant and an ERI during the study. Of these, four benefitted from two ERIs. The number of ERIs was significantly higher in the pediatric population than among adults. The explantation and reimplantation were performed simultaneously in 86% of cases. The reasons for explantation were: in 46.4% of cases linked to a malfunction of the implant, and in 39.3% of cases for medical or surgical reasons. The number of electrodes inserted was significantly higher after the ERI than after the first implantation. There was just one post-ERI infection for these 95 explanted and re-implanted patients. As well as explantation with reimplantation rarely being necessary, it generally presents no major surgical difficulty and in most cases it allows a better integration than in the first implantation.

The French National Cochlear Implant Registry (EPIIC): Results, quality of life, questionnaires, academic and professional life

This study concerns the results of cochlear implantation in children and adults from French cochlear implantation centers, monitored at one, two and three years by the Cochlear Implant French Registry EPIIC. This multicenter study enrolled 2603 subjects (1667 adults and 936 children) implanted in one ear. The following parameters were studied: hearing overall performances, monosyllabic or dissyllabic word perception, speech intelligibility, self-assessment questionnaire of Cochlear Implant (CI) benefits (Abbreviated profile of Hearing aid Benefit); professional activity and schooling. This study confirms the ceiling effect in adults' performances after the 1^st year and the progressive growth in children's performances. It also shows that the contralateral hearing aid enhances performances compared to the CI alone condition, in all follow-up sessions. The French register of CIs is the only worldwide register of systematic follow-up on a period of three years and more of all adults and children implanted in a country.

The French National Cochlear Implant Registry (EPIIC): Cochlear implantation in adults over 65years old

OBJECTIVES

To analyze the performance of cochlear implants in French patients aged 65 and over, implanted between 2012 and 2016, using data from the French national registry for cochlear implants (EPIIC).

MATERIALS AND METHODS

The French national registry incorporates patient data from before implantation and for three years after implantation, stratified in different age groups (18-39, 40-64years, 65-74years and>75years). Here, we assessed the latter two categories. Hearing was assessed using mono- and disyllabic words in a silent background. The Category of Auditory Performance (CAP) scale was also implemented and subjects took the Abbreviated Profile of Hearing Aid Benefit (Aphab) questionnaire.

RESULTS

The population aged over 65 accounted for 38% (n=1193) of the 3178 adult implanted patients. The performance for mono- and disyllabic words in silence, the CAP scores and the APHAB questionnaire answers for ease of communication, background noise and reverberation were dramatically improved at one year post-implantation (P<0.0001 for each score) and remained stable between one and three years thereafter. The percentage improvement was similar across all age groups. The scores for loud-noise intolerance did not change after cochlear implantation in any age group.

CONCLUSION

Cochlear implants improve hearing and communication in subjects aged 65 and over, with comparable efficiency to that achieved in younger subjects. Cochlear implantation should thus be proposed whenever hearing aids provide only limited benefit. However, between 2012 and 2016, cochlear implantation was given to less than 1% of the French population aged 65 and over with profound deafness.

μLAS technology for DNA isolation coupled to Cas9-assisted targeting for sequencing and assembly of a 30 kb region in plant genome

Cas9-assisted targeting of DNA fragments in complex genomes is viewed as an essential strategy to obtain high-quality and continuous sequence data. However, the purity of target loci selected by pulsed-field gel electrophoresis (PFGE) has so far been insufficient to assemble the sequence in one contig. Here, we describe the μLAS technology to capture and purify high molecular weight DNA. First, the technology is optimized to perform high sensitivity DNA profiling with a limit of detection of 20 fg/μl for 50 kb fragments and an analytical time of 50 min. Then, μLAS is operated to isolate a 31.5 kb locus cleaved by Cas9 in the genome of the plant Medicago truncatula. Target purification is validated on a Bacterial Artificial Chromosome plasmid, and subsequently carried out in whole genome with μLAS, PFGE or by combining these techniques. PacBio sequencing shows an enrichment factor of the target sequence of 84 with PFGE alone versus 892 by association of PFGE with μLAS. These performances allow us to sequence and assemble one contig of 29 441 bp with 99% sequence identity to the reference sequence.

Aeolian noise of a cylinder in the critical regime

The noise from the flow around a circular cylinder in the critical regime is investigated by combining a compressible wall-resolved large eddy simulation and a Ffowcs Williams and Hawkings analogy on solid and porous surfaces. This simulation is validated by comparing several flow parameters with previous experimental and numerical data in the same flow regime. Significantly reduced drag and increased vortex shedding Strouhal number (0.33) are observed. Two slightly asymmetric laminar separation bubbles (LSBs) on the cylinder surface at about 100° are shown to trigger turbulence through Kelvin-Helmholtz (KH) shear-layer instability. The latter contributes to a narrowband hump in the wall-pressure fluctuations with a tone at a Strouhal number of 27, which can be as intense as the dominant vortex shedding tone. The ratio of the corresponding Strouhal numbers is consistent with the proposed variation with the Reynolds number by Prasad and Williamson [(1997). J. Fluid Mech. 333, 375-402]. The dominant far-field noise source is still the vortex shedding dipolar tone radiating mostly at 90°. Yet, two additional broadband noise sources are evidenced in the wake, one at low frequencies caused by the wake oscillation and another one at high frequencies caused by the KH instability mostly directly toward the LSB locations.

Qu’écrivent les personnes atteintes d’hémopathies malignes dans leurs directives anticipées ? Analyse qualitative de 35 écrits

En France, les directives anticipées (DA) se sont vues reconnaître un statut légal en 2005, renforcé en 2016, toutefois une minorité de personnes fait le choix d’en rédiger. Dans le contexte de la maladie grave, quel est leur contenu ? Quelles informations relatives à leur prise en charge ou leur fin de vie y déposent-elles ? L’objectif de cette recherche qualitative est d’analyser le contenu des DA rédigées par des patients atteints d’hémopathies malignes afin de mieux comprendre leur appropriation. L’étude s’est déroulée en deux étapes sur une durée totale de huit ans et deux mois : un travail préliminaire, rétrospectif et monocentrique et une seconde étape prospective et multicentrique dans six sites français. L’analyse qualitative des DA a été accomplie par un binôme composé d’un hématologue sénior et d’un chercheur en sciences humaines et sociales. Une analyse thématique a été réalisée avec identification des principaux messages et mots clés. Les 35 DA collectées sont investies de trois façons différentes : l’appropriation est 1) purement juridique avec une citation de la loi in extenso sans personnalisation de l’écrit ; 2) centrée sur les actes et traitements médicaux souhaités ou refusés ; 3) un moyen de transmettre des messages personnels à l’attention de leurs proches comme leur confiance, l’amour qu’il leur porte ou les modalités d’obsèques souhaitées. En conclusion, nos résultats objectivent que la rédaction de DA ne se limite pas aux patients en fin de vie et qu’au-delà de la transmission d’informations relatives aux actes ou traitements médicaux, les patients les utilisent pour y déposer des messages personnels à leurs proches. Ce nouveau rôle des DA pourrait favoriser la communication intrafamiliale même si ce n’est pas leur finalité première. Faire évoluer les DA vers un concept plus large, comme une planification anticipée des soins, pourrait être un moyen de repenser l’outil et de toucher un plus grand nombre de personnes.

Whole-genome landscape of Medicago truncatula symbiotic genes

Advances in deciphering the functional architecture of eukaryotic genomes have been facilitated by recent breakthroughs in sequencing technologies, enabling a more comprehensive representation of genes and repeat elements in genome sequence assemblies, as well as more sensitive and tissue-specific analyses of gene expression. Here we show that PacBio sequencing has led to a substantially improved genome assembly of Medicago truncatula A17, a legume model species notable for endosymbiosis studies¹, and has enabled the identification of genome rearrangements between genotypes at a near-base-pair resolution. Annotation of the new M. truncatula genome sequence has allowed for a thorough analysis of transposable elements and their dynamics, as well as the identification of new players involved in symbiotic nodule development, in particular 1,037 upregulated long non-coding RNAs (lncRNAs). We have also discovered that a substantial proportion (~35% and 38%, respectively) of the genes upregulated in nodules or expressed in the nodule differentiation zone colocalize in genomic clusters (270 and 211, respectively), here termed symbiotic islands. These islands contain numerous expressed lncRNA genes and display differentially both DNA methylation and histone marks. Epigenetic regulations and lncRNAs are therefore attractive candidate elements for the orchestration of symbiotic gene expression in the M. truncatula genome.

[Sedentary lifestyle and urinary incontinence in women: A literature review]

AIM

The sedentary lifestyle is defined by a lack of regular mobilizing activities in the activities of daily life. The purpose of this work was to gather data related to the potential link between urinary incontinence and sedentary lifestyle in women.

METHOD

A literature review (Pubmed/MEDLINE databases) based on keywords: women; urinary incontinence; sedentary; sedentary behavior; sedentary lifestyle; physical activity; exercise; sport, over the period 2008-2018 was carried out.

RESULTS

Five cross-sectional observational studies were analyzed. Overall, the data supported a link between sedentary behavior and urinary incontinence in women. Several potential confounding factors (age, body mass index, comorbidities, lower socio-familial support) have been identified in the literature. Pathophysiological mechanisms remain poorly established, potentially including metabolic factors, postural factors and muscle dysfunctions. Few articles respected the strict definition of sedentary lifestyle, and no prospective study investigating the causal link between meddle or long-term sedentary was highlighted.

CONCLUSION

The limited data available in the literature suggests that sedentary lifestyle is a risk factor for female urinary incontinence. Many confounding factors have been identified, justifying further studies evaluating more specifically the causal link between sedentary lifestyle and urinary incontinence in women.

Laser Capture Micro-Dissection Coupled to RNA Sequencing: A Powerful Approach Applied to the Model Legume Medicago truncatula in Interaction with Sinorhizobium meliloti

Understanding the development of multicellular organisms requires the identification of regulators, notably transcription factors, and specific transcript populations associated with tissue differentiation. Laser capture microdissection (LCM) is one of the techniques that enable the analysis of distinct tissues or cells within an organ. Coupling this technique with RNA sequencing (RNAseq) makes it extremely powerful to obtain a genome-wide and dynamic view of gene expression. Moreover, RNA sequencing allows two or potentially more interacting organisms to be analyzed simultaneously. In this chapter, a LCM-RNAseq protocol optimized for root and symbiotic root nodule analysis is presented, using the model legume Medicago truncatula (in interaction with Sinorhizobium meliloti in the nodule samples). This includes the description of procedures for plant material fixation, embedding, and micro-dissection; it is followed by a presentation of techniques for RNA extraction and amplification, adapted for the simultaneous analysis of plant and bacterial cells in interaction or, more generally, polyadenylated and non-polyadenylated RNAs. Finally, step-by-step statistical analyses of RNAseq data are described. Those are critical for quality assessment of the whole procedure and for the identification of differentially expressed genes.

[Tubulocystic renal cell carcinoma with poorly differentiated foci]

Tubulocystic renal cell carcinoma is a rare tumor with an indolent behavior in the majority of cases. In contrast, tubulocystic renal cell carcinoma with poorly differentiated foci has a bad prognosis with an aggressive and metastatic behavior. We present the case of a patient diagnosed with tubulocystic renal cell carcinoma with poorly differentiated foci.

Reprogramming of DNA methylation is critical for nodule development in Medicago truncatula

The legume-Rhizobium symbiosis leads to the formation of a new organ, the root nodule, involving coordinated and massive induction of specific genes. Several genes controlling DNA methylation are spatially regulated within the Medicago truncatula nodule, notably the demethylase gene, DEMETER (DME), which is mostly expressed in the differentiation zone. Here, we show that MtDME is essential for nodule development and regulates the expression of 1,425 genes, some of which are critical for plant and bacterial cell differentiation. Bisulphite sequencing coupled to genomic capture enabled the identification of 474 regions that are differentially methylated during nodule development, including nodule-specific cysteine-rich peptide genes. Decreasing DME expression by RNA interference led to hypermethylation and concomitant downregulation of 400 genes, most of them associated with nodule differentiation. Massive reprogramming of gene expression through DNA demethylation is a new epigenetic mechanism controlling a key stage of indeterminate nodule organogenesis during symbiotic interactions.

Understanding leachate flow in municipal solid waste landfills by combining time-lapse ERT and subsurface flow modelling - Part I: Analysis of infiltration shape on two different waste deposit cells

Landfill bioreactors are based on an acceleration of in-situ waste biodegradation by performing leachate recirculation. To quantify the water content and to evaluate the leachate injection system, in-situ methods are required to obtain spatially distributed information, usually electrical resistivity tomography (ERT). In a previous study, the MICS (multiple inversions and clustering strategy) methodology was proposed to improve the hydrodynamic interpretation of ERT results by a precise delimitation of the infiltration area. In this study, MICS was applied on two ERT time-lapse data sets recorded on different waste deposit cells in order to compare the hydrodynamic behaviour of leachate flow between the two cells. This comparison is based on an analysis of: (i) the volume of wetted waste assessed by MICS and the wetting rate, (ii) the infiltration shapes and (iii) the pore volume used by the leachate flow. This paper shows that leachate hydrodynamic behaviour is comparable from one waste deposit cell to another with: (i) a high leachate infiltration speed at the beginning of the infiltration, which decreases with time, (ii) a horizontal anisotropy of the leachate infiltration shape and (iii) a very small fraction of the pore volume used by the leachate flow. This hydrodynamic information derived from MICS results can be useful for subsurface flow modelling used to predict leachate flow at the landfill scale.

[Voluntariness and blood donation: Proceedings of an ethics seminar held at the National Institute for Blood Transfusion]

Voluntariness stands for one of the four pillars of ethics in blood donation; it is, however, more related to tradition than to legislation. Because it seems necessary to apply "marketing" techniques to blood collection in order to meet the needs in blood components, both in terms of quantity and quality, one wonders if this may be at the expense of this principle of voluntariness. This seminar-belonging actually to a series of seminars in Ethics in Transfusion Medicine-aimed at questioning the possible weakness of voluntariness in the field of blood donation. To achieve this goal, specialists of numerous disciplines in medical sciences, law and humanities gathered to discuss all related issues to voluntariness in blood donation.

A Laser Dissection-RNAseq Analysis Highlights the Activation of Cytokinin Pathways by Nod Factors in the Medicago truncatula Root Epidermis

Nod factors (NFs) are lipochitooligosaccharidic signal molecules produced by rhizobia, which play a key role in the rhizobium-legume symbiotic interaction. In this study, we analyzed the gene expression reprogramming induced by purified NF (4 and 24 h of treatment) in the root epidermis of the model legume Medicago truncatula Tissue-specific transcriptome analysis was achieved by laser-capture microdissection coupled to high-depth RNA sequencing. The expression of 17,191 genes was detected in the epidermis, among which 1,070 were found to be regulated by NF addition, including previously characterized NF-induced marker genes. Many genes exhibited strong levels of transcriptional activation, sometimes only transiently at 4 h, indicating highly dynamic regulation. Expression reprogramming affected a variety of cellular processes, including perception, signaling, regulation of gene expression, as well as cell wall, cytoskeleton, transport, metabolism, and defense, with numerous NF-induced genes never identified before. Strikingly, early epidermal activation of cytokinin (CK) pathways was indicated, based on the induction of CK metabolic and signaling genes, including the CRE1 receptor essential to promote nodulation. These transcriptional activations were independently validated using promoter:β-glucuronidase fusions with the MtCRE1 CK receptor gene and a CK response reporter (TWO COMPONENT SIGNALING SENSOR NEW). A CK pretreatment reduced the NF induction of the EARLY NODULIN11 (ENOD11) symbiotic marker, while a CK-degrading enzyme (CYTOKININ OXIDASE/DEHYDROGENASE3) ectopically expressed in the root epidermis led to increased NF induction of ENOD11 and nodulation. Therefore, CK may play both positive and negative roles in M. truncatula nodulation.

A new method for the evaluation of the end-to-end distance of the knee ligaments and popliteal complex during passive knee flexion

BACKGROUND

Accurate knowledge about the length variation of the knee ligaments (ACL, PCL, MCL and LCL) and the popliteal complex during knee flexion/extension is essential for modelling and clinical applications. The aim of the present study is to provide this information by using an original technique able to faithfully reproduce the continuous passive knee flexion-extension kinematics and to reliably identify each ligament/tendon attachment site.

METHODS

Twelve lower limbs (femur, tibia, fibula, patella) were tested and set in motion (0-120°) using an ad hoc rig. Tibio-femoral kinematics was obtained using an optoelectronic system. A 3D digital model of each bone was obtained using low-dosage stereoradiography. Knee specimens were dissected and the insertion of each ligament and popliteal complex were marked with radio opaque paint. ACL, PCL and MCL were separated into two bundles. Bone epiphyses were CT-scanned to obtain a digital model of each ligament insertion. Bones and attachment site models were registered and the end-to-end distance variation of each ligament/tendon was computed over knee flexion.

RESULTS

A tibial internal rotation of 18°±4° with respect to the femur was observed. The different bundles of the ACL, MCL and LCL shortened, whereas all bundles of the PCL lengthened. The popliteal complex was found to shorten until 30° of knee flexion and then to lengthen.

CONCLUSION

The end-to-end distance variation of the knee ligaments and popliteal complex can be estimated during knee flexion using a robust and reliable method based on marking the ligaments/tendon insertions with radiopaque paint.

LEVEL OF EVIDENCE

Level IV.

Reduction and fusion in high-grade L5-S1 spondylolisthesis by a single posterior approach. Results in 50 patients

INTRODUCTION

Treatment strategies in high-grade L5-S1 spondylolisthesis are controversial. Reduction of slippage, correction of lumbosacral kyphosis and the necessity of a complementary anterior approach are debated in the literature. The present study reports clinical and radiological outcome for reduction and instrumented fusion on a single posterior approach.

MATERIAL AND METHOD

A retrospective study included all consecutive adolescent and young adult patients operated on by a single surgeon (D.C.) for high-grade (Meyerding 3-4-5) L5-S1 spondylolisthesis. The technique consisted in reduction of lumbosacral kyphosis and posterolateral fusion on a single posterior approach without resection of the sacral dome or complementary anterior approach. Only cases of adult ptosis required impacted tibial interbody graft. Clinical complications, radiologic lumbopelvic results and sagittal balance were analyzed at last follow-up.

RESULTS

Fifty patients, with a mean age at surgery of 21±11 years, were followed up for a mean 5.5±4.6 years. Mean lumbosacral angle was reduced by 25° (from 76° to 101°; P<0.05), and mean listhesis grade by >50% (from 75% to 23%; P<0.0001), without correction loss at last follow-up. C7 sagittal offset was corrected (from 8° to 4°; P<0.05), with harmonization of lumbar (from 57° to 64°; P<0.001) and thoracic curvature (from 37° to 44°; P=0.1). Seventeen patients (34%) showed postoperative radicular deficit, without sequelae at last follow-up. There were no cauda equina lesions. Bone fusion was achieved in 42 patients (84%), in the same surgical step. After revision by complementary interbody graft, there was no residual non-union.

CONCLUSION

Surgery on a single posterior approach gave reliable results in high-grade spondylolisthesis in adolescents and young adults. The technique is not however, free of risk (transient neurologic deficit and non-union), and patients should be forewarned. Complementary interbody graft can be reserved to adult ptosis with incomplete reduction of lumbosacral kyphosis and to revision surgery for non-union.

LEVEL OF EVIDENCE

IV, retrospective study.

Standing radiological analysis with a low-dose biplanar imaging system (EOS system) of the position of the components in total hip arthroplasty using an anterior approach

Aims

The primary aim of this study was to analyse the position of the acetabular and femoral components in total hip arthroplasty undertaken using an anterior surgical approach.

Patients and Methods

In a prospective, single centre study, we used the EOS imaging system to analyse the position of components following THA performed via the anterior approach in 102 patients (103 hips) with a mean age of 64.7 years (sd 12.6). Images were taken with patients in the standing position, allowing measurement of both anatomical and functional anteversion of the acetabular component.

Results

The mean inclination of the acetabular component was 39° (standard deviation (sd) 6), the mean anatomical anteversion was 30° (sd 10), and the mean functional anteversion was 31° (sd 8) five days after surgery. The mean anteversion of the femoral component was 20° (sd 11). Anatomical and functional anteversion of the acetabular component differed by >  10° in 23 (22%) cases. Pelvic tilt was the only pre-operative predictive factor of this difference.

Conclusion

Our study showed that anteversion of the acetabular component following THA using the anterior approach was greater than the recommended target value, and that substantial differences were observed in some patients when measured using two different measurement planes. If these results are confirmed by further studies, and considering that the anterior approach is intended to limit the incidence of dislocation, a new correlation study for each reference plane (anatomical and functional) will be necessary to define a ‘safe zone’ for use with the anterior approach. Take home message: EOS imaging system is helpful in the pre-operative and post-operative radiological analysis of total hip arthroplasty. Cite this article: Bone Joint J 2016;98-B:326–333.

Full-length de novo assembly of RNA-seq data in pea (Pisum sativum L.) provides a gene expression atlas and gives insights into root nodulation in this species

Next-generation sequencing technologies allow an almost exhaustive survey of the transcriptome, even in species with no available genome sequence. To produce a Unigene set representing most of the expressed genes of pea, 20 cDNA libraries produced from various plant tissues harvested at various developmental stages from plants grown under contrasting nitrogen conditions were sequenced. Around one billion reads and 100 Gb of sequence were de novo assembled. Following several steps of redundancy reduction, 46 099 contigs with N50 length of 1667 nt were identified. These constitute the 'Caméor' Unigene set. The high depth of sequencing allowed identification of rare transcripts and detected expression for approximately 80% of contigs in each library. The Unigene set is now available online (http://bios.dijon.inra.fr/FATAL/cgi/pscam.cgi), allowing (i) searches for pea orthologs of candidate genes based on gene sequences from other species, or based on annotation, (ii) determination of transcript expression patterns using various metrics, (iii) identification of uncharacterized genes with interesting patterns of expression, and (iv) comparison of gene ontology pathways between tissues. This resource has allowed identification of the pea orthologs of major nodulation genes characterized in recent years in model species, as a major step towards deciphering unresolved pea nodulation phenotypes. In addition to a remarkable conservation of the early transcriptome nodulation apparatus between pea and Medicago truncatula, some specific features were highlighted. The resource provides a reference for the pea exome, and will facilitate transcriptome and proteome approaches as well as SNP discovery in pea.

State of the art of endoscopic frontal sinus cerebrospinal fluid leak repair

Frontal sinus cerebrospinal fluid leaks are rare and their surgical management is difficult. Up until recently, they could only be treated by open surgery with an osteoplastic flap. With the development of endoscopic surgery, less invasive techniques such as an exclusive endoscopic approach can now be used, ensuring a simpler postoperative course. However, these techniques require a thorough knowledge of frontal sinus anatomy and endoscopic CSF leak repair. This knowledge is essential both to ensure closure of the CSF leak and to preserve frontal sinus patency.

Efficient central nervous system AAVrh10-mediated intrathecal gene transfer in adult and neonate rats

Intracerebral administration of recombinant adeno-associated vector (AAV) has been performed in several clinical trials. However, delivery into the brain requires multiple injections and is not efficient to target the spinal cord, thus limiting its applications. To assess widespread and less invasive strategies, we tested intravenous (IV) or intrathecal (that is, in the cerebrospinal fluid (CSF)) delivery of a rAAVrh10-egfp vector in adult and neonate rats and studied the effect of the age at injection on neurotropism. IV delivery is more efficient in neonates and targets predominantly Purkinje cells of the cerebellum and sensory neurons of the spinal cord and dorsal root ganglia. A single intra-CSF administration of AAVrh10, single strand or oversized self-complementary, is efficient for the targeting of neurons in the cerebral hemispheres, cerebellum, brainstem and spinal cord. Green fluorescent protein (GFP) expression is more widespread in neonates when compared with adults. More than 50% of motor neurons express GFP in the three segments of the spinal cord in neonates and in the cervical and thoracic regions in adults. Neurons are almost exclusively transduced in neonates, whereas neurons, astrocytes and rare oligodendrocytes are targeted in adults. These results expand the possible routes of delivery of AAVrh10, a serotype that has shown efficacy and safety in clinical trials concerning neurodegenerative diseases.

Detorsion night-time bracing for the treatment of early onset idiopathic scoliosis

BACKGROUND

Management for early onset scoliosis has recently changed, with the development of new surgical procedures. However, multiple surgeries are often required and high complication rates are still reported. Conservative management remains an alternative, serial casting achieving excellent results in young children. Better compliance and improvement over natural history have been reported with night-time bracing in adolescent idiopathic scoliosis (AIS), but this treatment has never been reported in early onset idiopathic scoliosis (EIOS).

METHODS

All patients treated for progressive EOIS by detorsion night-time bracing (DNB), and meeting the Scoliosis Research Society (SRS) criteria for brace studies were reviewed. Recommendations were given to wear the DNB 8h/night and no restriction was given regarding sports activities. Radiological parameters were compared between referral and latest follow-up. Based on the SRS criteria defined for AIS, a similar classification was used as follows to analyze the course of the curves: success group: patients with a progression of 5° or less; unsuccess group (progression or failure): patients with a progression>5°, patients with curves exceeding 45° at maturity, or who have had recommendation for/undergone surgery, or patients who changed orthopaedic treatment, or who were lost to follow-up.

RESULTS

Thirty-three patients were included (21 girls and 12 boys), with a median Cobb angle of 31° (Q1-Q3: 22-40). Age at brace initiation averaged 50months (Q1-Q3: 25-60). Median follow-up was 102-months (Q1-Q3: 63-125). Fifteen patients (45.5%) had reached skeletal maturity at last follow-up. The success rate was 67% (22 patients), with a median Cobb angle reduction of 15° (P<0.001). Four patients stopped DNB due to an important regression. Eleven patients were in the unsuccessful group (33%). Only one had surgery. All patients remained balanced in the frontal plane and normokyphotic. Initial curve magnitude and age at brace initiation appeared to be important prognostic factors.

CONCLUSIONS

DNB is an effective conservative treatment, which can be considered a delaying tactic in the management of EOIS. This brace offers potential psychosocial and compliance benefits, and allows unconstrained spinal and chest wall growth, resulting in normokyphosis at maturity.

LEVEL OF EVIDENCE

Therapeutic study (retrospective consecutive case series): Level IV.

Do all Charcot Spine require surgery?

INTRODUCTION

Spinal neuroarthropathy (SNA), also called "Charcot spine", is very uncommon disease of unknown etiology. Kronig first reported this pathology in 1884 on a patient with Tabes dorsalis (also known as syphilitic myelopathy). As syphilis tends to disappear in developed countries, spinal cord lesion is the most frequent etiology of SNA.

OBJECTIVES

To describe clinical and radiographic results in 12 patients suffering from spinal neuroarthropathy (SNA).

METHODS

Twelve patients diagnosed with SNA were included in the study. All patients were wheelchair users. The average delay between the neurological disease and the diagnosis of SNA was 18 years. All patients were initially treated conservatively. Surgery was only indicated in persistent symptomatic or instable cases, and for infected SNA. Surgery was a circumferential arthrodesis.

RESULTS

From 12 patients, with a median follow-up of 4 years, five patients were operated on and 7 patients were still conservatively treated. Two patients with back pain and evolutive destruction were declined for surgery. One suffered of bilateral hip ankylosis and extensive spinal surgery would have confined him to bed, and one due to an evolutive bedsore. One patient improved with a complete regression of back pain.

CONCLUSION

Nowadays, surgical treatment is recommended with an extensive and circumferential fusion, in order to prevent relapses. Good radiographic outcome is reported but functional results have not been studied. Natural evolution of SNA remains unknown but can be less disabling than surgery. This pathologic mobility can contribute to patient's autonomy and can therefore be considered as opportune. Conservative therapy can be considered for SNA.

LEVEL OF EVIDENCE

Level IV.

Influence of the geomembrane on time-lapse ERT measurements for leachate injection monitoring

Leachate recirculation is a key process in the operation of municipal waste landfills as bioreactors. To quantify the water content and to evaluate the leachate injection system, in situ methods are required to obtain spatially distributed information, usually electrical resistivity tomography (ERT). However, this method can present false variations in the observations due to several parameters. This study investigates the impact of the geomembrane on ERT measurements. Indeed, the geomembrane tends to be ignored in the inversion process in most previously conducted studies. The presence of the geomembrane can change the boundary conditions of the inversion models, which have classically infinite boundary conditions. Using a numerical modelling approach, the authors demonstrate that a minimum distance is required between the electrode line and the geomembrane to satisfy the good conditions of use of the classical inversion tools. This distance is a function of the electrode line length (i.e. of the unit electrode spacing) used, the array type and the orientation of the electrode line. Moreover, this study shows that if this criterion on the minimum distance is not satisfied, it is possible to significantly improve the inversion process by introducing the complex geometry and the geomembrane location into the inversion tools. These results are finally validated on a field data set gathered on a small municipal solid waste landfill cell where this minimum distance criterion cannot be satisfied.

An integrated analysis of plant and bacterial gene expression in symbiotic root nodules using laser-capture microdissection coupled to RNA sequencing

Rhizobium-induced root nodules are specialized organs for symbiotic nitrogen fixation. Indeterminate-type nodules are formed from an apical meristem and exhibit a spatial zonation which corresponds to successive developmental stages. To get a dynamic and integrated view of plant and bacterial gene expression associated with nodule development, we used a sensitive and comprehensive approach based upon oriented high-depth RNA sequencing coupled to laser microdissection of nodule regions. This study, focused on the association between the model legume Medicago truncatula and its symbiont Sinorhizobium meliloti, led to the production of 942 million sequencing read pairs that were unambiguously mapped on plant and bacterial genomes. Bioinformatic and statistical analyses enabled in-depth comparison, at a whole-genome level, of gene expression in specific nodule zones. Previously characterized symbiotic genes displayed the expected spatial pattern of expression, thus validating the robustness of our approach. We illustrate the use of this resource by examining gene expression associated with three essential elements of nodule development, namely meristem activity, cell differentiation and selected signaling processes related to bacterial Nod factors and redox status. We found that transcription factor genes essential for the control of the root apical meristem were also expressed in the nodule meristem, while the plant mRNAs most enriched in nodules compared with roots were mostly associated with zones comprising both plant and bacterial partners. The data, accessible on a dedicated website, represent a rich resource for microbiologists and plant biologists to address a variety of questions of both fundamental and applied interest.

The symbiotic transcription factor MtEFD and cytokinins are positively acting in the Medicago truncatula and Ralstonia solanacearum pathogenic interaction

• A plant-microbe dual biological system was set up involving the model legume Medicago truncatula and two bacteria, the soil-borne root pathogen Ralstonia solanacearum and the beneficial symbiont Sinorhizobium meliloti. • Comparison of transcriptomes under symbiotic and pathogenic conditions highlighted the transcription factor MtEFD (Ethylene response Factor required for nodule Differentiation) as being upregulated in both interactions, together with a set of cytokinin-related transcripts involved in metabolism, signaling and response. MtRR4 (Response Regulator), a cytokinin primary response gene negatively regulating cytokinin signaling and known as a target of MtEFD in nodulation processes, was retrieved in this set of transcripts. • Refined studies of MtEFD and MtRR4 expression during M. truncatula and R. solanacearum interaction indicated differential kinetics of induction and requirement of central regulators of bacterial pathogenicity, HrpG and HrpB. Similar to MtRR4, MtEFD upregulation during the pathogenic interaction was dependent on cytokinin perception mediated by the MtCRE1 (Cytokinin REsponse 1) receptor. • The use of M. truncatula efd-1 and cre1-1 mutants evidenced MtEFD and cytokinin perception as positive factors for bacterial wilt development. These factors therefore play an important role in both root nodulation and root disease development.

The CCAAT box-binding transcription factor NF-YA1 controls rhizobial infection

Symbiosis between legume plants and soil rhizobia culminates in the formation of a novel root organ, the 'nodule', containing bacteria differentiated as facultative nitrogen-fixing organelles. MtNF-YA1 is a Medicago truncatula CCAAT box-binding transcription factor (TF), formerly called HAP2-1, highly expressed in mature nodules and required for nodule meristem function and persistence. Here a role for MtNF-YA1 during early nodule development is demonstrated. Detailed expression analysis based on RNA sequencing, quantitiative real-time PCR (qRT-PCR), as well as promoter-β-glucuronidase (GUS) fusions reveal that MtNF-YA1 is first induced at the onset of symbiotic development during preparation for, and initiation and progression of, symbiotic infection. Moreover, using a new knock-out mutant, Mtnf-ya1-1, it is shown that MtNF-YA1 controls infection thread (IT) progression from initial root infection through colonization of nodule tissues. Extensive confocal and electronic microscopic observations suggest that the bulbous and erratic IT growth phenotypes observed in Mtnf-ya1-1 could be a consequence of the fact that walls of ITs in this mutant are thinner and less coherent than in the wild type. It is proposed that MtNF-YA1 controls rhizobial infection progression by regulating the formation and the wall of ITs.

Retrospective study of Mycoplasma gallisepticum meningoencephalitis in six turkey flocks in western France

Mycoplasma gallisepticum (MG) meningoencephalitis was diagnosed in six turkey flocks, from 1998 to 2005, in the western part of France. Affected birds were 8-11 weeks old and all displayed neurological signs, especially torticollis, with more than half having concomitant respiratory signs. Microscopical examination of brain samples from birds in all six flocks revealed similar lesions of acute to subacute multifocal parenchymal necrosis, perivascular cuffing, leptomeningitis and vasculitis. Birds from four of the six affected flocks were seropositive for MG and in birds from four flocks MG DNA was detected by polymerase chain reaction performed on tracheal swabs or on samples of formalin-fixed and paraffin wax-embedded brain. To our knowledge, this is the first pathological description of naturally occurring cases of turkey MG meningoencephalitis in Europe.

Assessment and Characterization of Stress Induced by Via-First TSV Technology

Through silicon via (TSV) is a key enabling technology for 3D stacking. One of the main concerns regarding the TSV introduction inside the IC fabrication is the resulting stress buildup in the silicon substrate that may induce warpage or expansion at the wafer level, strain and crystalline defects in the neighboring silicon of the TSV, and finally can impact the performance and reliability of the CMOS devices as well. Polysilicon, tungsten, and copper are the three main conductors that are currently considered for TSV fabrication. In the first part of this paper, the different factors that contribute to the stress in these three TSV types, including the geometry, the materials, and the process, will be reviewed.

After bonding on a temporary carrier and thinning of the substrate to expose the via, the stress built up during the fabrication of the TSV can be also revealed by the expansion of the silicon membrane.

We present thermomechanical FEM simulations and compare them with the experimental findings. We also present some characterizations of silicon defects by chemical revelation around the TSV structures. For characterization of the stress in TSV structures, different techniques as EBSD, microRaman, and XRD are presented. Finally, we conclude that with the optimization of some key processing steps, the stress induced in via-first technology may be acceptable for IC integration.

Gastric juvenile polyposis with high-grade dysplasia in pachydermoperiostosis

Pachydermoperiostosis (PDP) is the primary form of hypertrophic osteoarthropathy. It is a very rare disease consisting of pachydermia, digital clubbing and radiologic periostosis. Various digestive symptoms in PDP are seen in 11-49% of patients and juvenile polyps may be found at gastric endoscopy. We report here the history of a patient with PDP who was referred for assessment of severe anemia. Endoscopy of the upper digestive tract showed multiple polyps of the stomach with two huge lesions exhibiting foci of high-grade dysplasia. This observation suggests that PDP can be considered as a precancerous condition of the stomach and systematic screening using endoscopy should be considered in these patients.