Spatio-temporal connectivity of a toxic cyanobacterial community and its associated microbiome along a freshwater-marine continuum

Due to climate changes and eutrophication, blooms of predominantly toxic freshwater cyanobacteria are intensifying and are likely to colonize estuaries, thus impacting benthic organisms and shellfish farming representing a major ecological, health and economic risk. In the natural environment, Microcystis form large mucilaginous colonies that influence the development of both cyanobacterial and embedded bacterial communities. However, little is known about the fate of natural colonies of Microcystis by salinity increase. In this study, we monitored the fate of a Microcystis dominated bloom and its microbiome along a French freshwater-marine gradient at different phases of a bloom. We demonstrated changes in the cyanobacterial genotypic composition, in the production of specific metabolites (toxins and compatible solutes) and in the heterotrophic bacteria structure in response to the salinity increase. In particular M. aeruginosa and M. wesenbergii survived salinities up to 20. Based on microcystin gene abundance, the cyanobacteria became more toxic during their estuarine transfer but with no selection of specific microcystin variants. An increase in compatible solutes occurred along the continuum with extensive trehalose and betaine accumulations. Salinity structured most the heterotrophic bacteria community, with an increased in the richness and diversity along the continuum. A core microbiome in the mucilage-associated attached fraction was highly abundant suggesting a strong interaction between Microcystis and its microbiome and a likely protecting role of the mucilage against an osmotic shock. These results underline the need to better determine the interactions between the Microcystis colonies and their microbiome as a likely key to their widespread success and adaptation to various environmental conditions.

Exploring the Exopolysaccharide Production Potential of Bacterial Strains Isolated from Tunisian Blue Crab Portunus segnis Microbiota

The blue crab (BC) Portunus segnis is considered an invasive species colonizing Tunisian coasts since 2014. This work aims to explore its associated bacteria potential to produce anionic exopolysaccharides (EPSs) in order to open up new ways of valorization. In this study, different BC samples were collected from the coastal area of Sfax, Tunisia. First, bacterial DNA was extracted from seven different fractions (flesh, gills, viscera, carapace scraping water, and three wastewaters from the production plant) and then sequenced using the metabarcoding approach targeting the V3-V4 region of the 16S rDNA to describe their microbiota composition. Metabarcoding data showed that the dominant bacterial genera were mainly Psychrobacter, Vagococcus, and Vibrio. In parallel, plate counting assays were performed on different culture media, and about 250 bacterial strains were isolated and identified by sequencing the 16S rDNA. EPS production by this new bacterial diversity was assessed to identify new compounds of biotechnological interest. The identification of the bacterial strains in the collection confirmed the dominance of Psychrobacter spp. strains. Among them, 43 were identified as EPS producers, as revealed by Stains-all dye in agarose gel electrophoresis. A Buttiauxella strain produced an EPS rich in both neutral sugars including rare sugars such as rhamnose and fucose and uronic acids. This original composition allows us to assume its potential for biotechnological applications and, more particularly, for developing innovative therapeutics. This study highlights bacterial strains associated with BC; they are a new untapped source for discovering innovative bioactive compounds for health and cosmetic applications, such as anionic EPS.

Screening for precancerous anal lesions linked to human papillomaviruses: French recommendations for clinical practice

In France, about 2000 new cases of anal cancer are diagnosed annually. Squamous cell carcinoma is the most common histological type, mostly occurring secondary to persistent HPV16 infection. Invasive cancer is preceded by precancerous lesions. In addition to patients with a personal history of precancerous lesions and anal cancer, three groups are at very high risk of anal cancer: (i) men who have sex with men and are living with HIV, (ii) women with a history of high-grade squamous intraepithelial lesions (HSILs) or vulvar HPV cancer, and (iii) women who received a solid organ transplant more than 10 years ago. The purpose of screening is to detect HSILs so that they can be treated, thereby reducing the risk of progression to cancer. All patients with symptoms should undergo a proctological examination including standard anoscopy. For asymptomatic patients at risk, an initial HPV16 test makes it possible to target patients at risk of HSILs likely to progress to cancer. Anal cytology is a sensitive test for HSIL detection. Its sensitivity is greater than 80% and exceeds that of proctological examination with standard anoscopy. It is indicated in the event of a positive HPV16 test. In the presence of cytological abnormalities and/or lesions and a suspicion of dysplasia on clinical examination, high-resolution anoscopy is indicated. Performance is superior to that of proctological examination with standard anoscopy. However, this technique is not widely available, which limits its use. If high-resolution anoscopy is not possible, screening by a standard proctological examination is an alternative. There is a need to develop high-resolution anoscopy and triage tests and to evaluate screening strategies.

From genomics to integrative species delimitation? The case study of the Indo-Pacific Pocillopora corals

With the advent of genomics, sequencing thousands of loci from hundreds of individuals now appears feasible at reasonable costs, allowing complex phylogenies to be resolved. This is particularly relevant for cnidarians, for which insufficient data is available due to the small number of currently available markers and obscures species boundaries. Difficulties in inferring gene trees and morphological incongruences further blur the study and conservation of these organisms. Yet, can genomics alone be used to delimit species? Here, focusing on the coral genus Pocillopora, whose colonies play key roles in Indo-Pacific reef ecosystems but have challenged taxonomists for decades, we explored and discussed the usefulness of multiple criteria (genetics, morphology, biogeography and symbiosis ecology) to delimit species of this genus. Phylogenetic inferences, clustering approaches and species delimitation methods based on genome-wide single-nucleotide polymorphisms (SNP) were first used to resolve Pocillopora phylogeny and propose genomic species hypotheses from 356 colonies sampled across the Indo-Pacific (western Indian Ocean, tropical southwestern Pacific and south-east Polynesia). These species hypotheses were then compared to other lines of evidence based on genetic, morphology, biogeography and symbiont associations. Out of 21 species hypotheses delimited by genomics, 13 were strongly supported by all approaches, while six could represent either undescribed species or nominal species that have been synonymised incorrectly. Altogether, our results support (1) the obsolescence of macromorphology (i.e., overall colony and branches shape) but the relevance of micromorphology (i.e., corallite structures) to refine Pocillopora species boundaries, (2) the relevance of the mtORF (coupled with other markers in some cases) as a diagnostic marker of most species, (3) the requirement of molecular identification when species identity of colonies is absolutely necessary to interpret results, as morphology can blur species identification in the field, and (4) the need for a taxonomic revision of the genus Pocillopora. These results give new insights into the usefulness of multiple criteria for resolving Pocillopora, and more widely, scleractinian species boundaries, and will ultimately contribute to the taxonomic revision of this genus and the conservation of its species.

Sharing Vitamin B12 between Bacteria and Microalgae Does Not Systematically Occur: Case Study of the Haptophyte Tisochrysis lutea

Haptophyte microalgae are key contributors to microbial communities in many environments. It has been proposed recently that members of this group would be virtually all dependent on vitamin B12 (cobalamin), an enzymatic cofactor produced only by some bacteria and archaea. Here, we examined the processes of vitamin B12 acquisition by haptophytes. We tested whether co-cultivating the model species Tisochrysis lutea with B12-producing bacteria in vitamin-deprived conditions would allow the microalga to overcome B12 deprivation. While T. lutea can grow by scavenging vitamin B12 from bacterial extracts, co-culture experiments showed that the algae did not receive B12 from its associated bacteria, despite bacteria/algae ratios supposedly being sufficient to allow enough vitamin production. Since other studies reported mutualistic algae–bacteria interactions for cobalamin, these results question the specificity of such associations. Finally, cultivating T. lutea with a complex bacterial consortium in the absence of the vitamin partially rescued its growth, highlighting the importance of microbial interactions and diversity. This work suggests that direct sharing of vitamin B12 is specific to each species pair and that algae in complex natural communities can acquire it indirectly by other mechanisms (e.g., after bacterial lysis).

The extensive transgenerational transcriptomic effects of ocean acidification on the olfactory epithelium of a marine fish are associated with a better viral resistance

Background

Progressive CO₂-induced ocean acidification (OA) impacts marine life in ways that are difficult to predict but are likely to become exacerbated over generations. Although marine fishes can balance acid–base homeostasis efficiently, indirect ionic regulation that alter neurosensory systems can result in behavioural abnormalities. In marine invertebrates, OA can also affect immune system function, but whether this is the case in marine fishes is not fully understood. Farmed fish are highly susceptible to disease outbreak, yet strategies for overcoming such threats in the wake of OA are wanting. Here, we exposed two generations of the European sea bass (Dicentrarchus labrax) to end-of-century predicted pH levels (IPCC RCP8.5), with parents (F1) being exposed for four years and their offspring (F2) for 18 months. Our design included a transcriptomic analysis of the olfactory rosette (collected from the F2) and a viral challenge (exposing F2 to betanodavirus) where we assessed survival rates.

Results

We discovered transcriptomic trade-offs in both sensory and immune systems after long-term transgenerational exposure to OA. Specifically, RNA-Seq analysis of the olfactory rosette, the peripheral olfactory organ, from 18-months-old F2 revealed extensive regulation in genes involved in ion transport and neuronal signalling, including GABAergic signalling. We also detected OA-induced up-regulation of genes associated with odour transduction, synaptic plasticity, neuron excitability and wiring and down-regulation of genes involved in energy metabolism. Furthermore, OA-exposure induced up-regulation of genes involved in innate antiviral immunity (pathogen recognition receptors and interferon-stimulated genes) in combination with down-regulation of the protein biosynthetic machinery. Consistently, OA-exposed F2 challenged with betanodavirus, which causes damage to the nervous system of marine fish, had acquired improved resistance.

Conclusion

F2 exposed to long-term transgenerational OA acclimation showed superior viral resistance, though as their metabolic and odour transduction programs were altered, odour-mediated behaviours might be consequently impacted. Although it is difficult to unveil how long-term OA impacts propagated between generations, our results reveal that, across generations, trade-offs in plastic responses is a core feature of the olfactory epithelium transcriptome in OA-exposed F2 offspring, and will have important consequences for how cultured and wild fish interacts with its environment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08647-w.

Infection nosocomiale et clusters intra hospitalier d'infection à SARS cov 2 dans un centre hospitalier Général : Bilan d'une année de pandémie

Introduction

La mise à disposition large des tests PCR SARS cov2 et la stratégie de dépistage systématique autour d'un cas a permis de mettre en évidence la survenue de transmissions croisées entrainant des infections nosocomiales au sein des services de soins. Un cluster est défini par la présence d'au moins 3 cas dans un service de soins dans un délai de 14 jours. L'objectif de l'étude est de définir le nombre de cas d'infection nosocomiale et de phénomène de cluster hospitalier aux décours de la 2ème et 3ème vague d'infection à SARS cov 2 dans un centre hospitalier Général.

Matériels et méthodes

Etude rétrospective des infections nosocomiales et des clusters intra hospitalier entre avril 2020 et avril 2021 L'infection nosocomiale est définie par la négativité d'une PCR d'entrée et la positivité d'une PCR à plus de 7 jours de l'entrée. Un cluster est défini par au moins trois cas d'infection nosocomiale dans une même unité de lieux et de temps (14jours). La deuxième vague comprend les cas identifiés entre les mois d'octobre et décembre 2020 et janvier avril 2021 pour la troisième.

Résultats

Quatre mille deux cents cinq PCR positives ont été détectées entre avril 2020 et avril 2021. Le nombre covid nosocomiaux était de 123 des 1654 patients hospitalisés (7.4 %) et ayant un diagnostic virologique d'infection à SARScov2. Cent onze (79 %) des cas nosocomiaux étaient liés à des clusters. Durant la deuxième vague, 14 clusters ont été détectés dans 8 services différents (moyenne de 5 patients par épisodes avec au minimum 3 et au maximum 18 patients par cluster). Pendant la troisième vague, 4 clusters ont été identifiés dans 4 services. La durée moyenne de résolution des clusters a été de 14 jours. Les clusters ont été détectés pour 58 cas (47 %)en secteur médecine chirurgie obstétrique et pour 65 (53 %) cas en secteur soins de suite et rééducation.

La moyenne d'âge des cas nosocomiaux était de 83 ans, 85,37 % présentaient au moins une comorbidité et la mortalité a été de 22,76 % contre 19 % pour les cas communautaire (Xhi² = 1.03 NS).

Conclusion

L'acquisition nosocomiale du virus SARS cov 2 a été est un phénomène bien réel entrainant une surmortalité en milieu hospitalier. Ces données patients permettent de justifier les mesures spécifiques comme la vaccination précoce et obligatoire des personnels soignants et des patients à risque, un renforcement des mesures d'hygiène et un contrôle des visites.

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Psychiatry training goes virtual: the experience of the first online edition of the EPA Research Summer School

Introduction

The European Psychiatric Association (EPA) Summer School allows psychiatric trainees and early career psychiatrists (ECPs) from all over Europe to meet, network, and learn together. After the 2020 edition being cancelled due to COVID-19, the 10th edition in 2021 focused for the first time on research and was conducted remotely.

Objectives

To provide an overview and feedback about the first Virtual EPA Research Summer School as a new way to encourage international networking during COVID-19.

Methods

The School was organized by the EPA Secretary for Education, and 4 Faculty members. It started with a “breaking the ice session” one week before and then a two-days meeting on 23-24 September 2021 using an online video-platform. This was preceded by all the 21 participants (from 18 different countries) recording a short 4-minute video presentation, which was uploaded and shared with other participants and Faculty.

Results

Participants were divided on a voluntary basis into three working groups: 1) “Drug repurposing: overcoming challenges in pharmacoepidemiology” 2) “Psychopathological research in psychiatry”; 3) “How to conduct a cross-sectional survey?”. The Summer School program was composed of plenary sessions with lectures by the Faculty members, discussion sessions, and working groups time. At the end, each group presented a summary of the work done to the rest of the participants.

Conclusions

Although the remote format limits social interactions during the Summer School, overall participants’ high satisfaction and productivity indicate that not only online formats, but also the topic of research might be covered in future editions.

Disclosure

No significant relationships.

Making the most out of the EPA Research Summer School: from a group exercise to an international collaborative study protocol

Introduction

The 2021 Research Summer School took place virtually, and 7 psychiatric trainees or early career psychiatrists (ECPs) from 7 different European countries participated in a working group on how to conduct a cross-sectional survey study.

Objectives

To provide an overview of the process of developing an internationally collaborative protocol during the EPA Virtual Research Summer School.

Methods

All participants were asked by the Faculty mentor chairing this working group to write a research question that could be investigated through a cross-sectional survey. After a brainstorming discussion, it was decided to investigate the experiences, knowledge, and attitudes of psychiatric trainees and ECPs about electroconvulsive therapy (ECT) in Europe, an effective yet controversial procedure.

Results

The process of developing a protocol entailed different phases. First, a literature search was conducted, which supported the need to explore more the attitudes towards ECT among ECPs. Through group discussion the study’s objectives were decided, as well as the most appropriate methodology (including data collection and questionnaire use). At the end of the course, the core of the research plan was presented to all participants at the Research Summer School, preceding its implementation.

Conclusions

Participating in the EPA Research Summer School is a unique experience, a great learning opportunity, and can also lead to fruitful collaborations. It enabled the learning of the key aspects of designing and conducting a survey. In a short period of time, it was possible to design a study protocol for a future international cross-sectional survey on ECT.

Disclosure

No significant relationships.

The role of perinatal palliative care following prenatal diagnosis of major, incurable fetal anomalies: a multicentre prospective cohort study

OBJECTIVE

To describe prenatal decision-making processes and birth plans in pregnancies amenable to planning perinatal palliative care.

DESIGN

Multicentre prospective observational study.

SETTING

Nine Multidisciplinary Centres for Prenatal Diagnosis of the Paris-Ile-de-France region.

POPULATION

All cases of major and incurable fetal anomaly eligible for TOP where limitation of life-sustaining treatments for the neonate was discussed in the prenatal period between 2015 and 2016.

METHODS

Cases of congenital defects amenable to perinatal palliative care were prospectively included in each centre. Prenatal diagnosis, decision-making process, type of birth plan, birth characteristics, pregnancy and neonatal outcome were collected prospectively and anonymously.

MAIN OUTCOME MEASURE

Final decision reached following discussions in the antenatal period.

RESULTS

We identified 736 continuing pregnancies with a diagnosis of a severe fetal condition eligible for TOP. Perinatal palliative care was considered in 102/736 (13.9%) pregnancies (106 infants); discussions were multidisciplinary in 99/106 (93.4%) cases. Prenatal birth plans involved life-sustaining treatment limitation and comfort care in 73/736 (9.9%) of the pregnancies. The main reason for planning palliative care at birth was short-term inevitable death in 39 cases (53.4%). In all, 76/106 (71.7%) infants were born alive, and 18/106 (17%) infants were alive at last follow-up, including four with a perinatal palliative care birth plan.

CONCLUSIONS

Only a small proportion of severe and incurable fetal disorders were potentially amenable to limitation of life-sustaining interventions. Perinatal palliative care may not be considered a universal alternative to termination of pregnancy.

TWEETABLE ABSTRACT

Perinatal palliative care is planned in 10% of continuing pregnancies with a major and incurable fetal condition eligible for TOP.

Comparative Analysis of Fecal Microbiomes From Wild Waterbirds to Poultry, Cattle, Pigs, and Wastewater Treatment Plants for a Microbial Source Tracking Approach

Fecal pollution in coastal areas is of a high concern since it affects bathing and shellfish harvesting activities. Wild waterbirds are non-negligible in the overall signal of the detectable pollution. Yet, studies on wild waterbirds’ gut microbiota focus on migratory trajectories and feeding impact on their shape, rare studies address their comparison to other sources and develop quantitative PCR (qPCR)-based Microbial Source Tracking (MST) markers to detect such pollution. Thus, by using 16S rRNA amplicon high-throughput sequencing, the aims of this study were (i) to explore and compare fecal bacterial communities from wild waterbirds (i.e., six families and 15 species, n = 275 samples) to that of poultry, cattle, pigs, and influent/effluent of wastewater treatment plants (n = 150 samples) and (ii) to develop new MST markers for waterbirds. Significant differences were observed between wild waterbirds and the four other groups. We identified 7,349 Amplicon Sequence Variants (ASVs) from the hypervariable V3–V4 region. Firmicutes and Proteobacteria and, in a lesser extent, Actinobacteria and Bacteroidetes were ubiquitous while Fusobacteria and Epsilonbacteraeota were mainly present in wild waterbirds. The clustering of samples in non-metric multidimensional scaling (NMDS) ordination indicated a by-group clustering shape, with a high diversity within wild waterbirds. In addition, the structure of the bacterial communities was distinct according to bird and/or animal species and families (Adonis R² = 0.13, p = 10^–4, Adonis R² = 0.11, p = 10^–4, respectively). The Analysis of Composition of Microbiomes (ANCOM) showed that the wild waterbird group differed from the others by the significant presence of sequences from Fusobacteriaceae (W = 566) and Enterococcaceae (W = 565) families, corresponding to the Cetobacterium (W = 1427) and Catellicoccus (W = 1427) genera, respectively. Altogether, our results suggest that some waterbird members present distinct fecal microbiomes allowing the design of qPCR MST markers. For instance, a swan- and an oystercatcher-associated markers (named Swan_2 and Oyscab, respectively) have been developed. Moreover, bacterial genera harboring potential human pathogens associated to bird droppings were detected in our dataset, including enteric pathogens, i.e., Arcobacter, Clostridium, Helicobacter, and Campylobacter, and environmental pathogens, i.e., Burkholderia and Pseudomonas. Future studies involving other wildlife hosts may improve gut microbiome studies and MST marker development, helping mitigation of yet unknown fecal pollution sources.

Psychological impact of the SARS-CoV-2 outbreak on the staff of a French hospital

Background

The outbreak of SARS-CoV-2 has resulted in anxiety, depression and post-traumatic stress disorder (PTSD) among hospital staff. The factors associated with this psychological impact remain to be determined.

Methods

A cross-sectional study using an online questionnaire completed by the staff of a French hospital, two months after the SARS-CoV-2 outbreak.

Results

Among the 353 participants (of whom 67% were healthcare professionals), 32% had symptoms of anxiety, 16% of depression and 16% of PTSD. Eleven per cent had initiated or increased treatment with sleeping pills, and 6% with anxiolytics. In a multivariate analysis, factors independently associated with anxiety were: change of professional team, having a relative infected by SARS-CoV-2 and a new/increased treatment with sleeping pills or anxiolytics. The only factor associated with depression was the feeling of risk during professional practice. The factors associated with PTSD were: having a relative infected by SARS-CoV-2, the feeling of risk during professional practice, the increase in smoking and treatment with sleeping pills. The observance of transmission preventive measures (TPM) was not associated with the psychological impact of SARS-CoV-2. A personal history of SARS-CoV-2 infection and age < 36 years were associated with insufficient use of protective equipment. Age < 36 years, and being a healthcare professional were associated with the non-observance of social distancing.

Conclusion

The hospital staff displayed psychological consequences, resulting in the use of anxiolytics and sleeping pills. Belonging to a group with low-risk of severe disease was associated with lower observance of TPM.

Lignocellulose degradation at the holobiont level: teamwork in a keystone soil invertebrate

BACKGROUND

Woodlice are recognized as keystone species in terrestrial ecosystems due to their role in the decomposition of organic matter. Thus, they contribute to lignocellulose degradation and nutrient cycling in the environment together with other macroarthropods. Lignocellulose is the main component of plants and is composed of cellulose, lignin and hemicellulose. Its digestion requires the action of multiple Carbohydrate-Active enZymes (called CAZymes), typically acting together as a cocktail with complementary, synergistic activities and modes of action. Some invertebrates express a few endogenous lignocellulose-degrading enzymes but in most species, an efficient degradation and digestion of lignocellulose can only be achieved through mutualistic associations with endosymbionts. Similar to termites, it has been suspected that several bacterial symbionts may be involved in lignocellulose degradation in terrestrial isopods, by completing the CAZyme repertoire of their hosts.

RESULTS

To test this hypothesis, host transcriptomic and microbiome shotgun metagenomic datasets were obtained and investigated from the pill bug Armadillidium vulgare. Many genes of bacterial and archaeal origin coding for CAZymes were identified in the metagenomes of several host tissues and the gut content of specimens from both laboratory lineages and a natural population of A. vulgare. Some of them may be involved in the degradation of cellulose, hemicellulose, and lignin. Reconstructing a lignocellulose-degrading microbial community based on the prokaryotic taxa contributing relevant CAZymes revealed two taxonomically distinct but functionally redundant microbial communities depending on host origin. In parallel, endogenous CAZymes were identified from the transcriptome of the host and their expression in digestive tissues was demonstrated by RT-qPCR, demonstrating a complementary enzyme repertoire for lignocellulose degradation from both the host and the microbiome in A. vulgare.

CONCLUSIONS

Our results provide new insights into the role of the microbiome in the evolution of terrestrial isopods and their adaptive radiation in terrestrial habitats.

Can chemical and molecular biomarkers help discriminate between industrial, rural and urban environments?

Air samples from four contrasting outdoor environments including a park, an arable farm, a waste water treatment plant and a composting facility were analysed during the summer and winter months. The aim of the research was to study the feasibility of differentiating microbial communities from urban, rural and industrial areas between seasons with chemical and molecular markers such as microbial volatile organic compounds (MVOCs) and phospholipid fatty acids (PLFAs). Air samples (3l) were collected every 2h for a total of 6h in order to assess the temporal variations of MVOCs and PLFAs along the day. MVOCs and VOCs concentrations varied over the day, especially in the composting facility which was the site where more human activities were carried out. At this site, total VOC concentration varied between 80 and 170μgm^-3 in summer and 20-250μgm^-3 in winter. The composition of MVOCs varied between sites due to the different biological substrates including crops, waste water, green waste or grass. MVOCs composition also differed between seasons as in summer they are more likely to get modified by oxidation processes in the atmosphere and in winter by reduction processes. The composition of microbial communities identified by the analysis of PLFAs also varied among the different locations and between seasons. The location with higher concentrations of PLFAs in summer was the farm (7297ngm^-3) and in winter the park (11,724ngm^-3). A specific set of MVOCs and PLFAs that most represent each one of the locations was identified by principal component analyses (PCA) and canonical analyses. Further to this, concentrations of both total VOCs and PLFAs were at least three times higher in winter than in summer. The difference in concentrations between summer and winter suggest that seasonal variations should be considered when assessing the risk of exposure to these compounds.

Variation of Oxygenation Conditions on a Hydrocarbonoclastic Microbial Community Reveals Alcanivorax and Cycloclasticus Ecotypes

Deciphering the ecology of marine obligate hydrocarbonoclastic bacteria (MOHCB) is of crucial importance for understanding their success in occupying distinct niches in hydrocarbon-contaminated marine environments after oil spills. In marine coastal sediments, MOHCB are particularly subjected to extreme fluctuating conditions due to redox oscillations several times a day as a result of mechanical (tide, waves and currents) and biological (bioturbation) reworking of the sediment. The adaptation of MOHCB to the redox oscillations was investigated by an experimental ecology approach, subjecting a hydrocarbon-degrading microbial community to contrasting oxygenation regimes including permanent anoxic conditions, anoxic/oxic oscillations and permanent oxic conditions. The most ubiquitous MOHCB, Alcanivorax and Cycloclasticus, showed different behaviors, especially under anoxic/oxic oscillation conditions, which were more favorable for Alcanivorax than for Cycloclasticus. The micro-diversity of 16S rRNA gene transcripts from these genera revealed specific ecotypes for different oxygenation conditions and their dynamics. It is likely that such ecotypes allow the colonization of distinct ecological niches that may explain the success of Alcanivorax and Cycloclasticus in hydrocarbon-contaminated coastal sediments during oil-spills.

Genome-Wide Association Study of Acute Renal Graft Rejection

Acute renal rejection is a major risk factor for chronic allograft dysfunction and long-term graft loss. We performed a genome-wide association study to detect loci associated with biopsy-proven acute T cell-mediated rejection occurring in the first year after renal transplantation. In a discovery cohort of 4127 European renal allograft recipients transplanted in eight European centers, we used a DNA pooling approach to compare 275 cases and 503 controls. In an independent replication cohort of 2765 patients transplanted in two European countries, we identified 313 cases and 531 controls, in whom we genotyped individually the most significant single nucleotide polymorphisms (SNPs) from the discovery cohort. In the discovery cohort, we found five candidate loci tagged by a number of contiguous SNPs (more than five) that was never reached in iterative in silico permutations of our experimental data. In the replication cohort, two loci remained significantly associated with acute rejection in both univariate and multivariate analysis. One locus encompasses PTPRO, coding for a receptor-type tyrosine kinase essential for B cell receptor signaling. The other locus involves ciliary gene CCDC67, in line with the emerging concept of a shared building design between the immune synapse and the primary cilium.

Use of near infrared reflectance spectroscopy to predict phytate phosphorus, total phosphorus, and crude protein of common poultry feed ingredients

The purpose of the study that is presented herein was to develop near-infrared reflectance spectroscopy (NIRS) calibrations to predict total phosphorus (P), phytate-P, and protein concentrations of feed ingredients commonly used in monogastric feed formulation. Samples representing 14 vegetable ingredients (cereals, cereal by-products, and oilseed meals) were collected worldwide throughout 2013. The samples were assayed by standard wet chemical techniques for total P, phytate-P, and protein content. There was substantial variability in protein, phytate-P, and total P within and between ingredients used in the calibration set. Protein content varied from 76 to 487 g/kg. Total P ranged from 2.09 and 22.5 g/kg and phytate-P ranged from 0.99 and 13.8 g/kg. Within these broad ranges, NIRS values were highly correlated for determination of protein, total P, and phytate-P with a standard error of prediction equal to 9.06 g/kg, 0.80 g/kg, and 0.66 g/kg, respectively. The wide diversity and heterogeneity of the mix of feed ingredients allowed the development of NIRS calibrations of sufficient accuracy to help nutritionists control the nutritional composition of their feed.

Daclizumab Versus Rabbit Antithymocyte Globulin in High-Risk Renal Transplants: Five-Year Follow-up of a Randomized Study

We previously reported a randomized controlled trial in which 227 de novo deceased-donor kidney transplant recipients were randomized to rabbit antithymocyte (rATG, Thymoglobulin) or daclizumab if they were considered to be at high immunological risk, defined as high panel reactive antibodies (PRA), loss of a first kidney graft through rejection within 2 years of transplantation, or third or fourth transplantation. Patients treated with rATG had lower incidences of biopsy-proven acute rejection (BPAR) and steroid-resistant rejection at 1 year. Patients were followed to 5 years posttransplant in an observational study; findings are described here. Treatment with rATG was associated with a lower rate of BPAR at 5 years (14.2% vs. 26.0% with daclizumab; p = 0.035). Only one rATG-treated patient (0.9%) and one daclizumab-treated patient (1.0%) developed BPAR after 1 year. Five-year graft and patient survival rates, and renal function, were similar between the two groups. Overall graft survival at 5 years was significantly higher in patients without BPAR (81.0% vs. 54.8%; p < 0.001). In conclusion, rATG is superior to daclizumab for the prevention of BPAR among high-immunological-risk renal transplant recipients. Overall graft survival at 5 years was approximately 70% with either induction therapy, which compares favorably to low-risk cohorts.

[Incarceration of the retroverted uterus in the third trimester: report of 2 cases]

Incarceration of the retroverted gravid uterus in the third trimester is a rare but distinctive diagnosis. Initial symptoms are more frequently urinary and digestive symptoms which became more acute at the third trimester. Severe abdominal pain associated with bleeding in early labor leads to make the diagnosis during an emergency cesarean section. However, the typical features of the clinical transvaginal exam and the abdominal ultrasound exam can confirm easily this diagnosis. We report two additional cases where Joël-Cohen incision for cesarean section was possible after manual reposition of the uterus. We discuss the diagnostic approach and the management regarding a literature review.

Effects of Ar-H2-N2 microwave plasma on chitosan and its nanoliposomes blend thin films designed for tissue engineering applications

This work addresses the functionalization of chitosan thin films and its nanoliposomes blend films by a microwave-excited Ar/N2/H2 surface-wave plasma treatment which was found an effective tool to modify surface properties. Changes in the film properties (wettability, chemical composition, morphology) induced by the plasma treatment are studied using water contact angle measurements, X-ray photoelectron spectroscopy and scanning probe microscopy. The results suggest that hydrophilicity of the films is improved by plasma treatment in a plasma condition dependency manner. Water contact angle of chitosan films before and after plasma treatment are, respectively, 101° and 27°. Besides chemical changes on the surface, the nanoliposomes incorporation and plasma treatment also induce morphological modifications. Moreover, a correlation is found between the nanoliposomes composition and size, and the effects of plasma treatment. It is shown that the plasma treatment significantly improves the chitosan film functionalization. The effect of N2 content (88% and 100%) in the plasma gas mixture on the film etching is also pointed out.

The natural history of clinical operational tolerance after kidney transplantation through twenty-seven cases

We report here on a European cohort of 27 kidney transplant recipients displaying operational tolerance, compared to two cohorts of matched kidney transplant recipients under immunosuppression and patients who stopped immunosuppressive drugs and presented with rejection. We report that a lower proportion of operationally tolerant patients received induction therapy (52% without induction therapy vs. 78.3%[p = 0.0455] and 96.7%[p = 0.0001], respectively), a difference likely due to the higher proportion (18.5%) of HLA matched recipients in the tolerant cohort. These patients were also significantly older at the time of transplantation (p = 0.0211) and immunosuppression withdrawal (p = 0.0002) than recipients who rejected their graft after weaning. Finally, these patients were at lower risk of infectious disease. Among the 27 patients defined as operationally tolerant at the time of inclusion, 19 still display stable graft function (mean 9 ± 4 years after transplantation) whereas 30% presented slow deterioration of graft function. Six of these patients tested positive for pre-graft anti-HLA antibodies. Biopsy histology studies revealed an active immunologically driven mechanism for half of them, associated with DSA in the absence of C4d. This study suggests that operational tolerance can persist as a robust phenomenon, although eventual graft loss does occur in some patients, particularly in the setting of donor-specific alloantibody.

Phenotype-genotype correlation and follow-up in adult patients with hypokalaemia of renal origin suggesting Gitelman syndrome

INTRODUCTION

Gitelman syndrome (GS) is a tubulopathy caused by SLC12A3 gene mutations, which lead to hypokalaemic alkalosis, secondary hyperaldosteronism, hypomagnesaemia and hypocalciuria.

AIM

The aim of this study was to assess the prevalence of SLC12A3 gene mutations in adult hypokalaemic patients; to compare the phenotype of homozygous, heterozygous and non-mutated patients; and to determine the efficiency of treatment.

METHODS

Clinical, biological and genetic data were recorded in 26 patients.

RESULTS

Screening for the SLC12A3 gene detected two mutations in 15 patients (six homozygous and nine compound heterozygous), one mutation in six patients and no mutation in five patients. There was no statistical difference in clinical symptoms at diagnosis between the three groups. Systolic blood pressure tended to be lower in patients with two mutations (P=0.16). Hypertension was unexpectedly detected in four patients. Five patients with two mutated alleles and two with heterozygosity had severe manifestations of GS. Significant differences were observed between the three groups in blood potassium, chloride, magnesium, supine aldosterone, 24 h urine chloride and magnesium levels and in modification of the diet in renal disease. Mean blood potassium levels increased from 2.8 ± 0.3, 3.5 ± 0.5 and 3.2 ± 0.3 before treatment to 3.2 ± 0.5, 3.7 ± 0.6 and 3.7 ± 0.3 mmol/l with treatment in groups with two (P=0.003), one and no mutated alleles respectively.

CONCLUSION

In adult patients referred for renal hypokalaemia, we confirmed the presence of mutations of the SLC12A3 gene in 80% of cases. GS was more severe in patients with two mutated alleles than in those with one or no mutated alleles. High blood pressure should not rule out the diagnosis, especially in older patients.

[Minimize kidney failure in transplantation patients with proliferation signal inhibitors]

Chronic renal dysfunction is a multifactorial and frequent event after organ transplantation. The measurement or the estimation of glomerular filtration rate is essential to detect early progressive renal dysfunction. Proliferation signal inhibitors are nonnephrotoxic immunosuppressive drugs which may be useful to minimize calcineurin inhibitors-related side effects through a conversion strategy. Most studies in the setting of kidney transplantation showed improvement in glomerular filtration rate as high than conversion was early. Proliferation signal inhibitors may be included quickly in new immunosuppressive regimen for liver transplanted patients with chronic renal dysfunction.

[Immunosuppressive strategies and chronic graft dysfunction in kidney transplantation]

Chronic graft dysfunction is a major cause of return to dialysis. In the majority of cases, it is correlated with histological signs of cellular and/or humoral rejection, the nephrotoxicity of anticalcineurins, or nonspecific lesions of interstitial fibrosis and tubular atrophy. Although the incidence of acute rejection has considerably decreased, renal toxicity of the calcineurin inhibitors remains problematic. In cases of established nephrotoxicity, the use of non-nephrotoxic immunosuppressors such as mycophenolic acid or the proliferation signal inhibitors makes it possible to reduce or even stop the anticalcineurins. In prevention of anticalcineurin nephrotoxicity, many attempts to minimize or wean patients from them have shown that improvement in renal function is only obtained at the cost of an increase in the incidence of acute rejection. This makes it necessary to select patients who may benefit from anticalcineurin-sparing treatment, based on clinical, histological, and biological markers. Finally, long-term follow-up is also fundamental in order to validate the positive impact on renal function of this strategy in terms of graft survival.