[Neonatal sepsis by Citrobacter Freundii as a debut of cystic lymphatic malformation]. / Sepsis neonatal por Citrobacter Freundii como debut de malformación linfática quística.

Cystic lymphatic malformation (CLM) is a rare and benign entity caused by alterations in the embryological development of lymphatic structures. Its typical location is in the head and neck, although it has also been described at the abdominal level. It may not be evident in the first stages of life and its first manifestation may be a complication such as abdominal distension, hemorrhage, or sepsis, which may put the patient's life at risk. Surgical treatment is increasingly discussed, and less invasive techniques are proposed. OBJECTIVE: To describe an uncommon presentation of CLM, radiographic findings, complications, differential diagnosis, and both invasive and more conservative treatments. CLINICAL CASE: Newborn female infant consulted for fever and irritability, without specific signs on physical examination, with suspicion of sepsis. Ultrasonography showed a complex septate mass with cysts of different sizes encompassing the mesenteric vessels, supravesical location. In its most ante rior aspect, it presented a greater echogenicity that corresponded to the superinfected component. Magnetic resonance imaging identified a multitabulated cystic tumor corresponding to a complica ted mesenteric lymphangioma with signs of infection. Due to its size, which compressed the vena cava and the associated signs of complication, complete resection was decided with good subsequent evolution. CONCLUSION: The treatment of CLM in pediatric age is increasingly individualized and can vary from surgical resection to less invasive approaches that could reduce acute intraoperative or postoperative complications and mortality. In our case, the infection acted as sclerotherapy, mana ging to delimit the CLM and helping to improve the prognosis.

Estuarine dissolved speciation and partitioning of trace metals: a novel approach to study biogeochemical processes.

Estuaries are complex systems involving numerous biogeochemical gradients and processes that influence the behavior of trace metals. Lead (Pb), cadmium (Cd), and copper (Cu) speciation and partitioning were studied in the Gironde Estuary (SW France), using a multi-method approach in which data from innovative sensors and laboratory-based techniques were combined. For the first time in this system, the so-called dynamic fractions of the target metals (dissolved forms that are potentially bioavailable) were recorded on-board through voltammetry using unique antifouling gel-integrated microelectrode arrays (GIME) incorporated in a submersible sensing probe (TracMetal). Trace metals in the operationally defined dissolved <0.2 µm and <0.02 µm fractions, as well as complexed with suspended particles (collected after centrifugation) were quantified through sampling/laboratory-based techniques. High spatial resolution trace metal concentrations were monitored along the salinity gradient (S = 0.10 to S = 34.0) together with master bio-physicochemical parameters providing robust cruise-specific information on how well-known abiotic and biotic processes control the Gironde estuarine trace element partitioning, (i.e. conservative behavior, addition/removal). Combining conventional methods with GIME measurements showed: (i) the dominance of Cd dynamic species in the intra-estuarine total dissolved fraction (up to 90%), (ii) the importance of small colloids as trace metal carrier phases, desorbing and complexing dynamic fractions of Pb and Cu, and (iii) the potential influence of photo-redox processes remobilizing Pb under their dynamic forms (up to 80%). Data also suggest trace metal release/sorption by phytoplankton with an increase of dissolved Cu concentrations in the riverine branch, as well as Cu and Cd particulate concentrations showing higher levels towards productive coastal waters. This complete approach allowed to monitor key estuarine biogeochemical processes and highlighted the valuable use of the TracMetal to record subtle variations of potentially bioavailable dissolved metal fractions.

Improving sample preheating capabilities for dynamic loading on high-pulsed power drivers.

The CEA operates several High-Pulsed Power (HPP) drivers for dynamic loading experiments. The aim of these experiments is to provide quantitative information about the response of various materials of interest, mainly under quasi-isentropic compression. In order to improve our ability to explore these materials' behavior over a wide range of thermodynamic paths and starting from various non-ambient conditions, we developed a device capable of pre-heating both metallic and nonmetallic samples up to several hundred degrees prior to loading. This device is based on conductive heating and on a configuration that allows homogeneous heating with unprecedented temperature stability on our HPP platforms. Moreover, it is designed to allow efficient sample heating, within extremely severe electromagnetic environments associated with such platforms. The main features of this preheating device, whose design was guided by extensive thermal simulations, are presented, along with various technical solutions that enabled its insertion in a reliable experimental configuration on our HPP drivers. The results obtained from preliminary experiments on a composite material (carbon fibers embedded in epoxy resin) and on a high purity copper sample preheated to 323 K and 573 K, respectively, are presented. The performance and robustness of this heating device are potentially valuable for extending the range of studies in dynamic loading experiments for various materials under ramp compression using HPP drivers.

Lipidomic and transcriptomic analyses of Chlamydomonas reinhardtii under heat stress unveil a direct route for the conversion of membrane lipids into storage lipids.

Studying how photosynthetic cells modify membrane lipids in response to heat stress is important to understand how plants and microalgae adapt to daily fluctuations in temperature and to investigate new lipid pathways. Here, we investigate changes occurring in lipid molecular species and lipid metabolism genes during early response to heat stress in the model photosynthetic microorganism Chlamydomonas reinhardtii. Lipid molecular species analyses revealed that, after 60 min at 42 °C, a strong decrease in specific polyunsaturated membrane lipids was observed together with an increase in polyunsaturated triacylglycerols (TAGs) and diacylglycerols (DAGs). The fact that decrease in the major chloroplastic monogalactosyldiacylglycerol sn1-18:3/sn2-16:4 was mirrored by an accumulation of DAG sn1-18:3/sn2-16:4 and TAG sn1-18:3/sn2-16:4/sn3-18:3 indicated that newly accumulated TAGs were formed via direct conversion of monogalactosyldiacylglycerols to DAGs then TAGs. Lipidomic analyses showed that the third fatty acid of a TAG likely originated from a phosphatidylethanolamine or a diacylglyceryl-O-4'-(N,N,N,-trimethyl)-homoserine betaine lipid species. Candidate genes for this TAG synthesis pathway were provided through comparative transcriptomic analysis and included a phospholipase A2 homolog and the DAG acyltransferase DGTT1. This study gives insights into the molecular events underlying changes in membrane lipids during heat stress and reveals an alternative route for TAG synthesis.

French adaptation of the new Knee Society Scoring System for total knee arthroplasty.

INTRODUCTION: In November 2011, the Knee Society published its new KSS score to evaluate objective clinical data and also patient expectations, satisfaction and knee function during various physical activities before and after total knee arthroplasty (TKA). We undertook the French cross-cultural adaptation of this scoring system according to current recommendations. HYPOTHESIS: The French version of the new KSS score is a consistent, feasible, reliable and discriminating score. PATIENTS AND METHODS: Eighty patients with knee osteoarthritis were recruited from two centers: one group of 40 patients had a TKA indication, while the other group of 40 patients had an indication for conservative treatment. After the new KSS score was translated and back-translated, it was compared to three other validated instruments (KOOS, AMIQUAL and SF-12) to determine construct validity, discriminating power, feasibility in terms of response rate and existence of floor or ceiling effect, internal consistency with Chronbach's alpha and reliability based on reproducibility and sensitivity to change (responsiveness). RESULTS: Due to missing data, two cases were eliminated. We found that the score could discriminate between groups; it had a nearly 100% response rate, a ceiling effect in the "expectations" domain, satisfactory Chronbach's alpha, excellent reproducibility and good responsiveness. DISCUSSION: These results confirm that the French version of the new KSS score is reliable, feasible, discriminating, consistent and responsive. The novelty of this scoring system resides in the "expectations" and "satisfaction" domains, its availability as a self-assessment questionnaire and the evaluation of function during various activities. LEVEL OF PROOF, TYPE OF STUDY: Level III.

Genetic diversity of Flavobacterium psychrophilum isolated from rainbow trout in France: predominance of a clonal complex.

Flavobacterium psychrophilum is the causative agent of "bacterial cold water disease" and "rainbow trout fry syndrome" in salmonid farming worldwide. These diseases, especially rainbow trout fry syndrome, are among the main hazards for French aquaculture. In this study, a multilocus sequence typing approach (MLST) was used to evaluate the genetic diversity of this bacterium. Seven housekeeping genes in a set of 66 isolates were investigated. They were recently collected from rainbow trout during clinical episodes in French farms from the two main geographical areas of production. A total of 5808 bp of sequence were analyzed for each isolate and showed relatively low levels of gene (H=0.4313) and nucleotide (π×100=0.31%) diversities. MLST identified 15 sequence types (STs), of which 14 have never been described. eBURST analysis separated the 15 STs in one clonal complex of 8 genetically related STs (with ST2 as founder) and 7 singletons. Genetic diversity was largely due to recombination, as demonstrated by a pairwise homoplasy index (PHI=5.35×10(-9)) significantly different from zero (p<0.05). The evolution of standardized association index (I(A)(S)) (all isolates: 0.6088, p<0.05; single representative of STs: 0.4567, p<0.05; and clusters of STs: 0.084, p>0.05), showed an epidemic structure of the population. These results emphasized the expansion of a limited number of dominant genetic variants in French clinical F. psychrophilum isolates from a single host species, with no geographic relationships.

A customised collared polished stem may reduce the complication rate of impaction grafting in revision hip surgery: a 12-year follow-up study.

We describe the results of 81 consecutive revision total hip replacements with impaction grafting in 79 patients using a collared polished chrome-cobalt stem, customised in length according to the extent of distal bone loss. Our hypothesis was that the features of this stem would reduce the rate of femoral fracture and subsidence of the stem. The mean follow-up was 12 years (8 to 15). No intra-operative fracture or significant subsidence occurred. Only one patient suffered a post-operative diaphyseal fracture, which was associated with a fall. All but one femur showed incorporation of the graft. No revision for aseptic loosening was recorded. The rate of survival of the femoral component at 12 years, using further femoral revision as the endpoint, was 100% (95% confidence interval (CI) 95.9 to 100), and at nine years using re-operation for any reason as the endpoint, was 94.6% (95% CI 92.0 to 97.2). These results suggest that a customised cemented polished stem individually adapted to the extent of bone loss and with a collar may reduce subsidence and the rate of fracture while maintaining the durability of the fixation.

Fate of arsenic-bearing phases during the suspended transport in a gold mining district (Isle river Basin, France).

Arsenic-rich (~140-1520 mg x kg(-1)) suspended particulate matter (SPM) was collected daily with an automatic sampler in the Upper Isle River (France) draining a former gold mining district in order to better understand the fate of arsenic during the suspended transport (particles smaller than 50 µm). Various techniques at a micrometric scale (EPMA, quantitative SEM-EDS with an automated particle counting including classification system and µXRD) were used to directly characterize As-bearing phases. The most frequent ones were aggregates of fine clay particles. Their mineralogy varied with particle sources involved. These aggregates were formed by chlorite-phlogopite-kaolinite assemblages during the high flow and chlorite-illite-montmorillonite during the low flow. Among all the observed As-carriers in SPM, these clay assemblages were the least As-rich (0.10 up to 1.58 wt.% As) and their median As concentrations suggested that they were less concentrated during the high flow than during the low flow. Iron oxyhydroxides were evidenced by µXRD in these clay aggregates, either as micro- to nano-sized particles and/or as coating. (Mn, Fe)oxyhydroxides were also present as discrete particles. Manganese oxides (0.14-1.26 wt.% As) transport significantly more arsenic during the low flow than during the high flow (0.16-0.79 wt.% As). The occurrence of Fe oxyhydroxide particles appeared more complex. During the low flow, observations on banks and in wetlands of freshly precipitated Fe hydroxides (ferrihydrite-type) presented the highest As concentrations (up to 6.5 wt.% As) but they were barely detected in SPM at a microscale. During the high flow, As-rich Fe-oxyhydroxides (0.10-2.80 wt.% As) were more frequent, reflecting mechanical erosion and transport when the surface water level increased. Arsenic transfers from SPM to corresponding aqueous fraction mostly depend on As-carrier stability. This study shows the temporal occurrence of each type of As-bearing phases in SPM, their As concentrations at a particle scale and abundance according to hydrological periods.

[Practice guidelines of the use of bisphosphonates in solid tumours with bone metastases and in multiple myeloma]. / Guide de recommandations d'utilisation des bisphosphonates dans les lésions osseuses malignes des tumeurs solides et du myélome multiple.

Bisphosphonates are indicated for the treatment of bone lesions in patients with solid tumours or multiple myeloma. Bisphosphonates have proven their effectiveness in reducing the number of bone complications (hypercalcemia, pain, disease-related fractures, spinal cord compression) and delaying their occurrence in patients with bone tumours; they have also been shown to reduce the need for bone surgery and palliative or pain-relieving radiotherapy in these patients. International recommendations for the treatment of bone lesions related to malignant solid tumours and multiple myeloma have been established. We have elaborated clinical practice guidelines on the use of bisphosphonates to assist treatment decision-making in bone oncology. The guide contains decision trees and tables with information to guide pre-treatment evaluation and patient follow-up, as well as indications and conditions of use of bisphosphonates. In 2007, the regional cancer network of Rhône-Alpes, ONCORA, formed a working group (GIP ONCORA) to elaborate the guideline. The final version was then discussed and adopted at a plenary session in July 2009, during a collaborative workshop on supportive care recommendations organized by ONCORA and the regional cancer network of Lorraine.

Mercury methylation rates of biofilm and plankton microorganisms from a hydroelectric reservoir in French Guiana.

The Petit-Saut ecosystem is a hydroelectric reservoir covering 365km(2) of flooded tropical forest. This reservoir and the Sinnamary Estuary downstream of the dam are subject to significant mercury methylation. The mercury methylation potential of plankton and biofilm microorganisms/components from different depths in the anoxic reservoir water column and from two different sites along the estuary was assessed. For this, reservoir water and samples of epiphytic biofilms from the trunk of a submerged tree in the anoxic water column and from submerged branches in the estuary were batch-incubated from 1h to 3 months with a nominal 1000ng/L spike of Hg(II) chloride enriched in (199)Hg. Methylation rates were determined for different reservoir and estuarine communities under natural nutrient (reservoir water, estuary freshwater) and artificial nutrient (culture medium) conditions. Methylation rates in reservoir water incubations were the highest with plankton microorganisms sampled at -9.5m depth (0.5%/d) without addition of biofilm components. Mercury methylation rates of incubated biofilm components were strongly enhanced by nutrient addition. The results suggested that plankton microorganisms strongly contribute to the total Hg methylation in the Petit-Saut reservoir and in the Sinnamary Estuary. Moreover, specific methylation efficiencies (%Me(199)Hg(net)/cell) suggested that plankton microorganisms could be more efficient methylating actors than biofilm consortia and that their methylation efficiency may be reduced in the presence of biofilm components. Extrapolation to the reservoir scale of the experimentally determined preliminary methylation efficiencies suggested that plankton microorganisms in the anoxic water column could produce up to 27mol MeHg/year. Taking into account that (i) demethylation probably occurs in the reservoir and (ii) that the presence of biofilm components may limit the methylation efficiency of plankton microorganisms, this result is highly consistent with the annual net MeHg production estimated from mass balances (8.1mol MeHg/year, Muresan et al., 2008a).

[Osteonecrosis of the jaw and biphosphonates: imaging features]. / Ostéonécrose de la machoire sous biphosphonates: aspects radiologiques.

PURPOSE: 1) To review the pathophysiology of osteonecrosis of the jaw in patients receiving biphosphonates. 2) To review the imaging findings of osteonecrosis of the jaw and attempt to define pathognomonic imaging features. Materials and methods. Retrospective study of 15 patients with metastatic disease treated with biphosphonates. All available imaging studies including orthopantomograms, CT and bone scans were reviewed simultaneously by two radiologists (FO, DB). RESULTS: The most frequent imaging finding was osteolysis. Signs of biphosphonate impregnation were frequently observed: areas os osteosclerosis or heterogeneous demineralization due to abnormal bone remodeling. The outer cortex appeared duplicated in one case. Complications including fracture, sequestra, oroantral fistula and sinusitis may also occur. CONCLUSION: The imaging features of osteonecrosis remain fairly non-specific. Drug-related osteonecrosis of the jaw should nonetheless be suggested in the appropriate clinical setting in the presence of osteolysis associated with osteosclerosis. Imaging is helpful to assess the extent of the disease and detect complications for improved patient management.

Deconvolution of trace element (As, Cr, Mo, Th, U) sources and pathways to surface waters of a gold mining-influenced watershed.

The Upper Isle River (SW France) drains the second most productive gold-mining district of France. A high resolution survey during one hydrological year of As, Cl(-), Cr, Fe, Mn, Mo, SO(4)(2-), Th and U dissolved concentrations in surface water aimed to better understand pathways of trace element export to the river system downstream from the mining district. Dissolved concentrations of As (up to 35000 ng/L) and Mo (up to 292 ng/L) were about 3-fold higher than the regional dissolved background and showed a negative logarithmic relation with discharge. Dissolved concentrations of Cr (up to 483 ng/L), Th (up to 48 ng/L) and U (up to 184 ng/L) increased with discharge. Geochemical relationships between molar ratios in surface water, geochemical background as well as rain- and groundwater data were combined. The contrasting behavior of distinct element groups was explained by a scenario involving three seasonal components: (i) The high flow component is poorly concentrated in As and Mo but highly concentrated in Cr, Th, U. This has been attributed to diffuse sources such as water-soil interactions, atmospheric inputs, bedrock and bed sediment weathering. Although this component probably also includes a contribution by weathering of sulfide veins, this signal is masked by dilution. (ii) One low flow component presents high SO(4)(2-), Fe, As and Mo and moderate Cr, Th and U concentrations. This component has been attributed to point sources such as mine gallery effluents, mining waste weathering and groundwater inputs from natural and/or mining-induced sulfide oxidation in the ore deposit. (iii) A second low flow component showing high As plus Mo concentrations associated with very low SO(4)(2-), Fe, Cr, Th and U concentrations, probably reflects trace element scavenging by ferric oxyhydroxide formation in the adjacent aquifer. This is supported by the decrease of Fe, Cr, Th and U in surface waters. Flux estimates suggest contrasting element-specific impacts on annual dissolved fluxes. Runoff may account for the major part of annual dissolved As, Mo, Th and U fluxes in the Upper Isle River. Inputs related to sulfide oxidation respectively contributed approximately 30% and approximately 24% to annual As and Mo fluxes. The formation of ferric oxyhydroxides strongly retained Cr, Th and U during the low flow, limiting their dissolved concentrations in surface waters. If this process may eventually decrease As mobility, its impact on dissolved As concentrations in surface water may be limited or/and counterbalanced by As release during sulfide oxidation.

Essential veterinary education in fish health and disease: a global perspective.

Fish are the largest class of vertebrates, with over 25,000 estimated species and subspecies. Fish have evolved unique anatomical and physiological adaptations, when compared to terrestrial vertebrates, for life in a range of aquatic environments. Interest in aquatic animal health has been recorded in Eastern and Western cultures for more than 2,000 years. In recent times, there has been an increase in the numbers of aquatic animals being used as companion animals or pets, for food and in laboratories, as well as in restoration and conservation programmes. There has also been a corresponding increase in concern for their health and welfare. Moral and ethical considerations require the optimisation of husbandry practices and advances in aquatic animal health for these animals. As with other vertebrates, veterinarians are best equipped to meet the challenges for aquatic animal health from clinical, scientific and legal perspectives. To accomplish this goal, veterinary education must incorporate aquatic animal health throughout graduate curricula, create advanced postgraduate training opportunities, and support a continuum of professional development opportunities for all levels of aquatic animal health expertise.

Efectividad a medio plazo de una intervención educativa grupal dirigida al cuidado de los pies en pacientes con diabetes tipo 2 / Medium-term effectiveness of a group educational intervention on foot care in patients with type 2 diabetes

Objetivo. Evaluar la efectividad a medio plazo de una intervención educativa grupal en atención primaria, dirigida a mejorar las habilidades en el autocuidado de los pies en pacientes con diabetes tipo 2 y determinar el momento más adecuado para una nueva intervención. Método. Estudio intervención antes-después con seguimiento tras 24 meses. Muestra de 76 pacientes con diabetes 2 que asistieron a 2 talleres de educación grupal. Se midieron variables sociodemográficas y variables relacionadas con el estado neurovascular del pie y con los hábitos de higiene y cuidado. Para la comparación de resultados se usó la prueba de McNemar para datos apareados. Resultados. Edad media 66 años, 51% varones. Evolución de hábitos antes-después (8 meses) de la intervención: higiene correcta 41-86%, hidratación buena-regular 80-97%, lavado de pies diario 42-68%, utensilios correctos 41-79%, calzado adecuado 9-33%, uñas correctas 26-74%, todas estas diferencias con p < 0,001. Entre los pacientes que mejoraron a raíz del taller, el 76% mantuvo la variable higiene correcta (intervalo de confianza [IC] del 95%, 61-90%) a los 24 meses, hidratación el 100%, lavado diario el 70% (IC del 95%, 51-90%), utensilios adecuados el 74% (IC del 95%, 58-90%), calzado adecuado el 55% (IC del 95%, 34-77%) y uñas correctas el 81% (IC del 95%, 68-94%). Conclusiones. La intervención ha mejorado todas las variables relacionadas con el cuidado del pie diabético estudiadas. El efecto del taller se mantiene a 24 meses en al menos el 70% de los participantes para todas las variables, excepto en el calzado adecuado. La educación grupal favorece el cambio de hábitos. Creemos indicada una intervención educativa cada 24 meses

Aim. To evaluate the medium-term effectiveness of a group educational intervention in primary care aimed at improving attitudes and skillsin self-care of the feet in patients with type 2 diabetes, and to determine the optimal time for reintervention. Method. We performed a before-after intervention study with a 24-month follow-up. The sample consisted of 76 patients with type 2 diabetes who underwent two group education sessions. Sociodemographic variables and variables related to the neurovascular statusof the foot and with hygiene and self-care habits were measured. To compare the results, McNemar’s test for paired data was used.Results. The mean age was 66 years and 51% were men. Skills performance before-after (8 months) the intervention were as follows:correct hygiene 41%-86%, good-medium hydration 80%-97%, daily foot washing 42%-68%, proper tools use 41%-79%, proper shoes 9%-33%, proper nails 26%-74% (all differences with p < 0.001). Among patients that improved due to the sessions, skills were stillcorrect at 24 months in 76% (95% CI: 61%-90%) for hygiene, 100% for hydration, 70% for daily foot washing (95% CI: 51%-90%), 74% for proper tools use (95% CI: 58-90%), 55% for proper shoes (95% CI: 34%-77%) and 81% for proper nails (95% CI: 68%-94%).Conclusions. The intervention improved all the skills studied. The effects of the sessions were still evident after 24 months in more than 70% of patients for all the variables studied except proper shoe use. Group education favors skills improvement. We suggest repeating the intervention every 24 months

Phylogeny.fr: robust phylogenetic analysis for the non-specialist.

Phylogenetic analyses are central to many research areas in biology and typically involve the identification of homologous sequences, their multiple alignment, the phylogenetic reconstruction and the graphical representation of the inferred tree. The Phylogeny.fr platform transparently chains programs to automatically perform these tasks. It is primarily designed for biologists with no experience in phylogeny, but can also meet the needs of specialists; the first ones will find up-to-date tools chained in a phylogeny pipeline to analyze their data in a simple and robust way, while the specialists will be able to easily build and run sophisticated analyses. Phylogeny.fr offers three main modes. The 'One Click' mode targets non-specialists and provides a ready-to-use pipeline chaining programs with recognized accuracy and speed: MUSCLE for multiple alignment, PhyML for tree building, and TreeDyn for tree rendering. All parameters are set up to suit most studies, and users only have to provide their input sequences to obtain a ready-to-print tree. The 'Advanced' mode uses the same pipeline but allows the parameters of each program to be customized by users. The 'A la Carte' mode offers more flexibility and sophistication, as users can build their own pipeline by selecting and setting up the required steps from a large choice of tools to suit their specific needs. Prior to phylogenetic analysis, users can also collect neighbors of a query sequence by running BLAST on general or specialized databases. A guide tree then helps to select neighbor sequences to be used as input for the phylogeny pipeline. Phylogeny.fr is available at: http://www.phylogeny.fr/

Long-term survey of heavy-metal pollution, biofilm contamination and diatom community structure in the Riou Mort watershed, South-West France.

In a metal-polluted stream in the Riou Mort watershed in SW France, periphytic biofilm was analyzed for diatom cell densities and taxonomic composition, dry weight and metal bio-accumulation (cadmium and zinc). Periphytic diatom communities were affected by the metal but displayed induced tolerance, seen through structural impact (dominance of small, adnate species) as well as morphological abnormalities particularly in the genera Ulnaria and Fragilaria. Species assemblages were characterized by taxa known to occur in metal-polluted environments, and shifts in the community structure expressed seasonal patterns: high numbers of Eolimna minima, Nitzschia palea and Pinnularia parvulissima were recorded in Summer and Autumn, whereas the species Surirella brebissonii, Achnanthidium minutissimum, Navicula lanceolata and Surirella angusta were dominant in Winter and Spring. Commonly used indices such as the Shannon diversity index and Specific Pollution Sensitivity Index reflected the level of pollution and suggest seasonal periodicity, the lowest diversities being observed in Summer.

Connected populations for detecting quantitative trait loci and testing for epistasis: an application in maize.

Quantitative trait loci (QTL) detection experiments have often been restricted to large biallelic populations. Use of connected multiparental crosses has been proposed to increase the genetic variability addressed and to test for epistatic interactions between QTL and the genetic background. We present here the results of a QTL detection performed on six connected F(2) populations of 150 F(2:3) families each, derived from four maize inbreds and evaluated for three traits of agronomic interest. The QTL detection was carried out by composite interval mapping on each population separately, then on the global design either by taking into account the connections between populations or not. Epistatic interactions between loci and with the genetic background were tested. Taking into account the connections between populations increased the number of QTL detected and the accuracy of QTL position estimates. We detected many epistatic interactions, particularly for grain yield QTL (R(2) increase of 9.6%). Use of connections for the QTL detection also allowed a global ranking of alleles at each QTL. Allelic relationships and epistasis both contribute to the lack of consistency for QTL positions observed among populations, in addition to the limited power of the tests. The potential benefit of assembling favorable alleles by marker-assisted selection are discussed.

[Evaluation of the organization of pre and post transfusion screening of viral infection markers in blood recipients in France in 2001]. / Evaluation de l'organisation du dépistage sérologique pré- et post-transfusionnel en France en 2001.

In France, data collection related to blood recipient's viral infectious disease markers pre and post-transfusion is a legal requirement for hospitals. Our study aimed to evaluate the actual modalities of this extensive screening in 2001, six years after the Ministry of health issued recommendations. A questionnaire was sent to the haemovigilance correspondents in hospitals having transfused labile blood products (LBP) in 2001. A total of 1463 hospitals having transfused 85% of LBP in France responded. 82.4% of hospitals have written guidelines for pre-transfusion screening of viral markers, mainly for HIV and hepatitis C. A frozen repository storage is held by 23.9% of hospitals with storage durations between 1 to 40 years. 84% of hospitals have written guidelines for post-transfusion screening. The test prescriptions are mostly done by physicians from clinical services and they include in more than 80% of cases, HIV and HCV markers. Only 12% of hospitals recontact the patient in case of a no show. Even though 77.5% of responding hospitals have labile blood products recipients follow up processes, their effectiveness remains quite low, only 16% of recipients having test results available at the hospital.

Geochemical survey and metal bioaccumulation of three bivalve species (Crassostrea gigas, Cerastoderma edule and Ruditapes philippinarum) in the Nord Medoc salt marshes (Gironde estuary, France).

A 15-month experiment combining a geochemical survey of Cd, Cu, Zn and Hg with a bioaccumulation study for three filter-feeding bivalve species (oysters, Crassostrea gigas; cockles, Cerastoderma edule; and clams, Ruditapes philippinarum) was conducted in a breeding basin of the Nord Medoc salt marshes connected to the Gironde estuary, which is affected by historic polymetallic pollution. Regular manual surface measurements of temperature, salinity, pH and dissolved O(2) concentration and hourly multiprobe in situ measurements throughout several periods for 6-8 weeks were performed. The geochemical behavior of metals in water, suspended particulate matter and sediment and their ecotoxicological impact on the three bivalve species were evaluated by in situ exposure of juvenile oysters (water column) and adult cockles and clams (sediment surface). The physico-chemical parameters reflected seasonal variations and basin management. A distinct daily periodicity (except salinity) indicated intense photosynthesis and respiration. In summer, low dissolved O(2) saturations ( approximately 40-50%) occurred in the early morning at 30 cm above the sediment, whereas in depressions, the water column near the sediment surface was suboxic. Cadmium, Zn and Cu concentrations in suspended particulate matter exceeded typical estuarine values and were much higher than the homogeneously distributed concentrations in different depth ranges of the basin sediment. Particles collected in sediment traps showed intermediate metal concentrations close to sediment values. These results suggest trace metal recycling due to reductive dissolution under suboxic conditions at the sediment surface resulting in trace metal release to the water column and adsorption onto suspended particles. Dissolved Cd, Zn and Hg concentrations (e.g. 13-136 ng l(-1); 0.3-25.1 microg l(-1) and 0.5-2.0 ng l(-1), respectively) in the basin corresponded to the concentration range typically observed in the Gironde estuary, except for some maximum values attributed to metal recycling. In contrast, dissolved Cu concentrations (1.08-6.08 microg l(-1)) were mostly higher than typical estuarine values, probably due to recycled Cu complexation by dissolved organic matter. Growth, bioaccumulation rates and kinetics in the whole soft body of the bivalves were analyzed every 40 days. Although Cd bioaccumulation of oysters was lower in the basin than in the estuary during the same period (27,000 ng g(-1), dry weight and 40,000 ng g(-1), respectively) these values are largely above the new human consumption safety level (5000 ng g(-1), dw; European Community, 2002). For cockles and clams, Cd bioaccumulation was lower, reaching 1400 ng g(-1) and 950 ng g(-1), respectively. Similar results were obtained for Zn and Cu suggesting physiological differences between the species and/or differences in the exposure of the organisms due to physico-chemical conditions and metal distribution between dissolved and particulate phases. In contrast, Hg bioaccumulation was highest for cockles reaching bioconcentration factors of approximately 200,000, which even exceeded that of Cd in oysters (50,000) for the same exposition period. Nevertheless, Hg concentrations remained relatively low in the three bivalve species.

Rickettsia felis, from culture to genome sequencing.

Rickettsia felis has been recently cultured in XTC2 cells. This allows production of enough bacteria to create a genomic bank and to sequence it. The chromosome of R. felis is longer than that of previously sequenced rickettsiae and it possess 2 plasmids. Microscopically, this bacterium exhibits two forms of pili: one resembles a conjugative pilus and another forms hair-like projections that may play a role in pathogenicity. R. felis also exhibits several copies of ankyrin-repeat genes and tetratricopeptide encoding gene that are specifically linked to pathogenic host-associated bacteria. It also contains toxin-antitoxin system encoding genes that are extremely rare in intracellular bacteria and may be linked to plasmid maintenance.