Prevalence, risk factors and molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) colonization in residents of long-term care facilities in Luxembourg, 2010.

A prevalence survey of methicillin-resistant Staphylococcus aureus (MRSA) was performed in 2010 in 19 long-term care facilities in Luxembourg. Of the 954 participating residents, 69 (7·2%) were colonized by MRSA. Previous history of MRSA [odds ratio (OR) 7·20, 95% confidence interval (CI) 3·19-16·27], quinolone therapy in the previous year (OR 2·27, 95% CI 1·17-4·41) and ≥24 h care administered per week (OR 4·29, 95% CI 1·18-15·56) were independent risk factors for MRSA colonization. More than 75% of strains were of clonal complex (CC)5, mainly spa-type t003 or sequence type (ST)225 and ST710, which is a rapidly emerging lineage prevalent in central Europe. Five residents were colonized by livestock-associated genotypes belonging to CC398. Previously dominant CC8 strains have recently been replaced by more resistant CC5 strains in Luxembourg.

Parental exposure to methyl methane sulfonate of three-spined stickleback: contribution of DNA damage in male and female germ cells to further development impairment in progeny.

Data regarding the link between DNA integrity of germ cells and the quality of progeny in fish exposed to genotoxicant are scarce although such information is of value to understand genotoxic effects of contaminants in aquatic fauna. This work aimed at studying the consequences of a parental exposure during the breeding season on offspring quality in three-spined stickleback. After in vivo exposure of adult fish to methyl methane sulfonate, a model alkylating compound, a clear increase in DNA damage was observed in erythrocytes of both genders, here used as a biomarker of exposure. MMS exposure significantly affected sperm DNA integrity but neither female fecundity nor fertilization success. In order to understand the contribution of each sex to potential deleterious effects in progeny due to parental exposure, mating of males and females exposed or not to MMS, was carried out. Exposure of both males and females or of males alone led to a significant increase in both mortality during embryo-larval stages and abnormality rate at hatching that appeared to be sensitive stages. Thus, in accordance with recent studies carried out in other freshwater fish species, such development defects in progeny were clearly driven by male genome, known to be devoid of DNA repair capacity in spermatozoa. The next step will be to investigate the link between DNA damage in stickleback sperm and reproductive impairment in natural populations exposed to complex mixture of genotoxicants.

The goby fish Sicydium spp. as valuable sentinel species towards the chemical stress in freshwater bodies of West Indies.

Implementation of the European Water Framework Directive in tropical areas such as the French West Indies (FWI) requires to select relevant aquatic sentinel species for investigating the ecological status of surface waters. The present work aimed to study the biological response of the widespread fish Sicydium spp. towards river chemical quality in Guadeloupe island through a set of proper biomarkers. During a 2-year survey, the hepatic EROD activity, the micronucleus formation and the level of primary DNA strand breaks in erythrocytes were measured respectively as an enzymatic biomarker of exposure and genotoxicity endpoints in fish living upstream and downstream of two chemically-contrasted rivers. Hepatic EROD activity was shown to be variable along the time but always significantly higher in fish from the most contaminated river (Rivière aux Herbes) compared to the low contaminated one (Grande Rivière de Vieux-Habitants). Fish size did not influence EROD activity. Female fish exhibited a lower EROD activity compared to males depending on the catching period. We observed significant temporal variation in micronucleus frequency and primary DNA damage level measured in fish erythrocytes that did not depend on the fish size. Micronucleus frequency and to a lesser extent DNA damage were significantly higher in fish from the Rivière aux Herbes compared to the Grande Rivière de Vieux-Habitants. Our results argue for the interest of using Sicydium spp. as sentinel species to assess river quality and chemical pressures in FWI.

Motivations and personality characteristics of candidate sperm and oocyte donors according to parenthood status: a national study from the French CECOS network.

STUDY QUESTION: In a non-commercial national gamete donation programme, do the motivations and personality characteristics of candidate sperm and oocyte donors differ according to their parenthood status? SUMMARY ANSWER: Moderate differences exist between non-parent and parent candidate donors in motivations for gamete donation and representations as well as in personality characteristics. WHAT IS KNOWN ALREADY: Several studies have analysed the motivations and experiences of oocyte or sperm donors, but mainly in countries where gamete donation is a commercial transaction, and very few studies have reported results of personality traits using personality inventory tests. No study has specifically investigated the motivations and personality characteristics of candidate gamete donors according to parenthood status. STUDY DESIGN SIZE DURATION: A prospective study was carried out including 1021 candidate donors from 21 centres (in university hospitals) of the national sperm and egg banking network in France between November 2016 and December 2018. PARTICIPANTS/MATERIALS SETTING METHODS: In total, 1021 candidate gamete donors were included in the study. During their first visit, male (n = 488) and female candidate donors (n = 533) completed a questionnaire on sociodemographic characteristics, their motivations for donation and their representations of donation, infertility and family. Secondly, a NEO Personality Inventory (NEO-PI-R) exploring the Big Five personality traits was completed online. Results were compared between parent and non-parent candidate donors. MAIN RESULTS AND THE ROLE OF CHANCE: Altruistic values were the principal motive for donation irrespective of parenthood status. Reassurance about their fertility or preservation of sperm for future use was more often reported in non-parent than in parent candidate donors. With regard to representation of gamete donation or of the family, independently of their parenthood status, candidate donors more frequently selected social rather than biological representations. Mean personality characteristics were in the normal range. Non-parent candidate donors had higher scores on openness and depression than parents, while parent candidate donors appeared more social than non-parents. LIMITATIONS REASONS FOR CAUTION: The personality characteristics inventory was not completed by all candidate donors included in the study. However, family status did not differ between the two groups (NEO-PI-R completed (n = 525) or not), while the group who completed the NEO-PI-R had a higher educational level. This national study was performed in a country where gamete donation is subject to strict legislation. WIDER IMPLICATIONS OF THE FINDINGS: In a global context where reproductive medicine is commercialized and gamete donor resources are limited, this study found that altruism and social representations of gamete donation and family are the main motivations for gamete donation in a country which prohibits financial incentive. These findings are relevant for health policy and for gamete donation information campaigns. STUDY FUNDING/COMPETING INTERESTS: Grant from the Agence de la Biomédecine, France. The authors have nothing to disclose related to this study. TRIAL REGISTRATION NUMBER: N/A.

Constrained G4 structures unveil topology specificity of known and new G4 binding proteins.

G-quadruplexes (G4) are non-canonical secondary structures consisting in stacked tetrads of hydrogen-bonded guanines bases. An essential feature of G4 is their intrinsic polymorphic nature, which is characterized by the equilibrium between several conformations (also called topologies) and the presence of different types of loops with variable lengths. In cells, G4 functions rely on protein or enzymatic factors that recognize and promote or resolve these structures. In order to characterize new G4-dependent mechanisms, extensive researches aimed at identifying new G4 binding proteins. Using G-rich single-stranded oligonucleotides that adopt non-controlled G4 conformations, a large number of G4-binding proteins have been identified in vitro, but their specificity towards G4 topology remained unknown. Constrained G4 structures are biomolecular objects based on the use of a rigid cyclic peptide scaffold as a template for directing the intramolecular assembly of the anchored oligonucleotides into a single and stabilized G4 topology. Here, using various constrained RNA or DNA G4 as baits in human cell extracts, we establish the topology preference of several well-known G4-interacting factors. Moreover, we identify new G4-interacting proteins such as the NELF complex involved in the RNA-Pol II pausing mechanism, and we show that it impacts the clastogenic effect of the G4-ligand pyridostatin.

Breakthrough instruments and products steady-state and time-resolved photoluminescence using the FluoTime 300 spectrometer with a FluoMic add-on.

This report highlights the combination of the FluoTime 300 photoluminescence spectrometer with a FluoMic add-on as a powerful tool for photophysical research and applications, yielding spectral, temporal, and spatial information on a wide range of samples. The steady-state and time-resolved measurement capabilities of this combination are demonstrated reflecting a broad range of applications.

[The bioethics law revision: comparative analysis of contributions from different public and professional offices. Assisted Reproductive Technology, embryo and stem cells research, umbilical cord blood bank]. / La révision de la loi de bioéthique : analyse comparative des contributions de différents organismes publics ou professionnels. Assistance médicale à la procréation, recherche sur l'embryon et les cellules souches, banque de sang du cordon ombilical.

The revision of the bioethics law of 2004 must occur in a five year's time. For this revision, the authorities decided to organize general states of bioethics and requested the production of contributions by the companies, institutions or associations. These texts tackle various subjects, like the Assisted Reproductive Technologies, research on the embryo and the stem cells and the banks of umbilical cord blood. Certain opinions converge, others differ, but all take part in the great debate which will take place at the time of the general conference.

[Ovarian stimulation and follicular puncture risks]. / Risques de la stimulation ovarienne et du prélèvement ovocytaire.

The ovarian stimulation and the follicular puncture in ART present risks which must be planned in order to better prevent them. These complications are the ovarian hyperstimulation syndrome, the thromboembolic and carcinologic risks; the anaesthetic, hemorrhagic and infectious risks of the punctures. The presence of an endometrioma can generate an increase in the infectious risk.

Benefits and limits of sediment toxicity tests as an aid to decision-making.

With respect to the management of dredged sediments, a crucial issue is whether the removed materials (watered and/or processed) are disposed of or reused in an environmentally sound manner. In this context, the number of studies dealing with hazard or risk assessment has exponentially increased. This emphasis has resulted in the promotion and application of a very large variety of ecotoxicological tests. As a consequence, there is a clear need to highlight the scope and limitations of these tests for their appropriate selection and interpretation. In this paper we discuss the choice, implementation and interpretation of laboratory tests carried out on aquatic organisms at various levels of biological organization. We examine some experimental tools and methods in order to determine how suitable they are in regard to the objectives for which they are employed. To make this discussion more consistent our paper is based on results from research programmes conducted for governmental organizations and industrial partners. The Laboratoire des Sciences de l'Environnement (LSE) was involved with Cemagref de Lyon in a first methodological programme on risk assessment of scenarios of dredged sediment deposition. Another programme for a chemical company was implemented to assess the benefits of a physico-chemical treatment applied to contaminated dredged sediments in a scenario of reuse or deposit in gravel pits. Currently, the LSE is working on a programme of risk assessment for road sediments in valorization scenarios. From these programmes, we expose how single-species tests, as well as more complex bioassays and microcosm tests, can be used in an iterative step of risk assessment. Concerning microcosm tests, we also introduce a more realistic system that has been designed to simulate natural hydraulic conditions of gravel pits to assess the effects of toxicants on gravel pit aquatic biota during the sediment immersion phase and the sediment post-deposition phase (paper in preparation). The benefits of these ecotoxicological approaches are underlined, but limits are discussed with regard to several criteria: ecological relevance, realism, use for decision-making, cost and complexity of methods involved.

Genotoxic pressure of vineyard pesticides in fish: field and mesocosm surveys.

The present study deals with the genotoxicity assessment of vineyard pesticides in fish exposed in the field or in mesocosm conditions. Primary DNA damage was quantified as strand breaks using the single cell gel electrophoresis assay (Comet assay) applied to fish erythrocytes. In a first experiment, a significant genotoxic effect was observed following an upstream-downstream gradient in early life stages of brown trout (Salmo trutta fario) exposed in the Morcille River contaminated by a mixture of vineyard pesticides during three consecutive years. The pronounced response in terms of DNA damage reported in the present study could argue for a high sensitivity of fish early life stage and/or a high level of exposure to genotoxic compounds in the Morcille River. This stresses the interest in using trout larvae incubated in sediment bed to assess genotoxic compounds in the field. In a second experiment, adult European topminnow (Phoxinus phoxinus) were exposed in water running through artificial channels to a mixture of diuron and azoxystrobin, two of the main pesticides detected in the Morcille watershed. As compared with the unexposed channel, a 3-5-fold increase in the DNA damage was observed in fish exposed to chronic environmental pesticide concentrations (1-2 microg L(-1) for diuron and 0.5-1 microg L(-1) for axoxystrobin). A single 6h pulse of pesticide (14 microg L(-1) of diuron and 7 microg L(-1) of azoxystrobin) was applied to simulate transiently elevated chemical concentrations in the river following storm conditions. It did not increase genotoxicity. After a 1-month recovery period, DNA damage in exposed fish erythrocytes recovered to unexposed level, suggesting possible involvement of both repair mechanisms and cellular turnover in this transient response. This work highlights that vineyard treatment by pesticides and in particular diuron and azoxystrobin can represent a genotoxic threat to fish from contaminated watershed rivers.

Genotoxic potential associated with low levels of the Fusarium mycotoxins nivalenol and fusarenon X in a human intestinal cell line.

This study aims to assess the genotoxic potential of nivalenol (NIV) and fusarenon X (FusX), produced by various Fusarium on cereals. Toxins were applied in time and dose-dependent experiments to the human enterocyte-like Caco-2 cell-line, both in dividing (undifferentiated) and in 10-12 days post-confluent cells (differentiated). Genotoxicity was evaluated through the alkaline Comet assay in a concentration range defined for each toxin as below the cytotoxicity threshold IC(10), determined by the MTS and the neutral red assays, to prevent false positive results because of DNA damage stemming from necrosis. Thus, genotoxicity was explored in the sub-cytotoxic 0-0.5 microM and 0-0.05 microM ranges respectively for NIV and FusX as the latter was found about 10-fold more cytotoxic than NIV. For both toxins, a 3h exposure did not cause any DNA damage, unlike after 24 and 72 h exposure in post confluent Caco-2 cells where DNA damage was significantly observed with a dose-dependent relationship. In dividing cells, only FusX increases DNA strand breaks in the 0.01-0.05 microM range after 72 h. These results demonstrated the existence of a genotoxic potential for NIV and FusX at low exposure levels and could contribute to the risk assessment process of these toxins that are of growing concern.

Detection of Loa loa Microfilariae in Follicular Fluid During Assisted Reproductive Technology: Case Report and Review of the Literature.

We report on a case of loiasis revealed during an assisted reproductive technology (ART) cycle. Loa loa could limit implantation outcome. We propose to focus on an ART strategy with frozen embryos to treat the patient before any transfer.

Biomonitoring of the genotoxic potential of aqueous extracts of soils and bottom ash resulting from municipal solid waste incineration, using the comet and micronucleus tests on amphibian (Xenopus laevis) larvae and bacterial assays (Mutatox and Ames tests).

The management of contaminated soils and wastes is a matter of considerable human concern. The present study evaluates the genotoxic potential of aqueous extracts of two soils (leachates) and of bottom ash resulting from municipal solid waste incineration (MSWIBA percolate), using amphibian larvae (Xenopus laevis). Soil A was contaminated by residues of solvents and metals and Soil B by polycyclic aromatic hydrocarbons and metals. MSWIBA was predominantly contaminated by metals. Two genotoxic endpoints were analysed in circulating erythrocytes taken from larvae: clastogenic and/or aneugenic effects (micronucleus induction) after 12 days of exposure and DNA-strand-breaking potency (comet assay) after 1 and 12 days of exposure. In addition, in vitro bacterial assays (Mutatox and Ames tests) were carried out and the results were compared with those of the amphibian test. Physicochemical analyses were also taken into account. Results obtained with the amphibians established the genotoxicity of the aqueous extracts and the comet assay revealed that they were genotoxic from the first day of exposure. The latter test could thus be considered as a genotoxicity-screening tool. Although genotoxicity persisted after 12 days' exposure, DNA damage decreased overall between days 1 and 12 in the MSWIBA percolate, in contrast to the soil leachates. Bacterial tests detected genotoxicity only for the leachate of soil A (Mutatox). The results confirm the ecotoxicological relevance of the amphibian model and underscore the importance of bioassays, as a complement to physico-chemical data, for risk evaluation.

[How to improve assisted reproductive techniques results? Biological aspects]. / Comment améliorer nos résultats d'Assistance médicale à la procréation? Le point de vue du biologiste.

In spite of recent improvements in IVF, pregnancy rates remained dramatically low. Better criteria are therefore necessary to establish the viability of a transferable top quality embryo. Observation of both pronuclei patterns at the zygote stage and early cleavage appears to offer an additional prognostic tool, correlating with chromosomal status and IVF outcome. Developmental ability and morphological evaluation of the embryo on days 2-3 remains the most used and valid method of selection, even though it is not sufficient to select embryos with the higher implantation potential. Blastocyst culture is another possible strategy for selecting the ideal embryo with theoretical, reduced risk of aneuploidies, though not all major chromosomal aberrations are excluded by prolonged in-vitro-culture. Concerning micro-manipulation of embryo such as hatching or cleaning or cytoplasm transfer, only controversial data are still available. In the field of ART, recent meta-analysis could not conclude to a positive effect concerning hatching, blastocyst culture or systematic PGD-AS (preimplantation genetic diagnosis with aneuploidy screening). Beside the technological aspect, Quality Management System is of great importance. Staff development and monitoring of staff performance in the IVF laboratory has to be considered in the next future.

Kinetics and Mechanisms of γ' Reprecipitation in a Ni-based Superalloy.

The reprecipitation mechanisms and kinetics of γ' particles during cooling from supersolvus and subsolvus temperatures were studied in AD730(TM) Ni-based superalloy using Differential Thermal Analysis (DTA). The evolution in the morphology and distribution of reprecipitated γ' particles was investigated using Field Emission Gun Scanning Electron Microscopy (FEG-SEM). Depending on the cooling rate, γ' particles showed multi or monomodal distribution. The irregularity growth characteristics observed at lower cooling rates were analyzed in the context of Mullins and Sekerka theory, and allowed the determination of a critical size of γ' particles above which morphological instability appears. Precipitation kinetics parameters were determined using a non-isothermal JMA model and DTA data. The Avrami exponent was determined to be in the 1.5-2.3 range, suggesting spherical or irregular growth. A methodology was developed to take into account the temperature dependence of the rate coefficient k(T) in the non-isothermal JMA equation. In that regard, a function for k(T) was developed. Based on the results obtained, reprecipitation kinetics models for low and high cooling rates are proposed to quantify and predict the volume fraction of reprecipitated γ' particles during the cooling process.

Biomonitoring of the genotoxic potential of draining water from dredged sediments, using the comet and micronucleus tests on amphibian (Xenopus laevis) larvae and bacterial assays (Mutatox and Ames tests).

Management of contaminated dredged sediments is a matter of great human concern. The present investigation evaluates the genotoxic potential of aqueous extracts of five sediments from French channels (draining water from dredged sediments), using larvae of the frog Xenopus laevis. Two genotoxic endpoints were analyzed in larvae: clastogenic and/or aneugenic effects (micronucleus induction after 12 d of exposure) and DNA-strand breaking potency (comet assay after 1 and 12 d of exposure) in the circulating blood. Additionally, in vitro bacterial assays (Microtox and Ames tests) were carried out and the results were compared with those obtained with larvae. Physicochemical analyses were also taken into account. Analytical analyses highlighted in the five draining waters a heavy load of contaminants such as metals and hydrocarbons. The results obtained with the micronucleus test established the genotoxicity of three draining waters. The comet assay showed that all 5 draining waters were genotoxic after 1 d of exposure. Although 3 of them were still genotoxic after 12 d of exposure, DNA damage globally decreased between d 1 and 12. The comet assay can be considered as a genotoxicity-screening tool. Data indicate that both tests should be used in conjunction in Xenopus. Bacterial tests (Ames) revealed genotoxicity for only one draining water. The results confirm the relevance of the amphibian model and the need to resort to bioassays in vivo such as the Xenopus micronucleus and comet assays for evaluation of the ecotoxicological impact, an essential complement to the physicochemical data.

[Early spontaneous ileal perforations in preterm infants: report of 4 cases]. / Perforations iléales précoces sans signes d'entérocolite ulcéronécrosante: à propos de quatre cas survenus chez des prématurés.

An ileal perforation occurred shortly after birth in 4 very premature newborns. Diagnosis was made on an abdominal distension with a pneumoperitoneum on X-ray. There were no biological, radiological nor histological signs of necrotizing enterocolitis. There were no digestive short- or long-term complications. According to the few authors who described this syndrome, there are some risk factors, but they were not clearly involved in our cases. Ileal perforation in the absence of signs of necrotizing enterocolitis is rarely reported but should be well known because of its good prognosis.

Glucocorticoid-mediated potentiation of P450 induction in primary culture of rainbow trout hepatocytes.

Induction of 7-ethoxyresorufin O-deethylase activity (a cytochrome P450IA-dependent activity) by beta-naphthoflavone (0.36 microM) is increased 2-3-fold by dexamethasone or cortisol (10(-9)-10(-7) M) in rainbow trout hepatocyte cultures. This potentiation does not seem to be a time-dependent process and could be a classical glucocorticoid receptor-mediated event resulting in enhanced transcriptional activation of the CYP1A, as previously shown in mammals. Since glucocorticoid levels can increase in fish exposed to pollutants, such steroids may interfere with the induction response to xenobiotics.

Dye-loaded zeolite L sandwiches as artificial antenna systems for light transport

The synthesis and characterization of dye loaded zeolite L sandwiches acting as artificial antenna systems for light harvesting and transport is reported. A set of experimental tools for the preparation of neutral dye-zeolite L materials ranging from low to maximum packing densities has been developed. The role of co-adsorbed water and the distribution of molecules between the inner and the outer surface were found to be the determining parameters. p-Terphenyl (pTP) turned out to be very suitable for studying these and other relevant parameters of neutral dye-zeolite L materials. We observed that pTP located in the channels of zeolite L can reversibly be displaced by water. This can be used when synthesizing such materials. We also observed that all-trans-1,6-diphenyl-1,3,5-hexatriene (DPH) which is very photolabile in solution is stable after insertion into zeolite L. By combining our extensive knowledge of these systems with ion-exchange procedures developed in an earlier study, we have realized the first bi-directional three-dye antenna. In this material the near UV absorbing compounds DPH or 1,2-bis-(5-methyl-benzoxazol-2-yl)-ethene (MBOXE) are located in the middle part of zeolite L nanocrystals followed on both sides by pyronine (Py) and then by oxonine (Ox) as acceptors. Fluorescence of the oxonine located at both ends of the cylindrical zeolite L crystals was observed upon excitation of the near UV absorber in the middle section at 353 nm, where neither oxonine nor pyronine absorb a significant amount of the excitation light.

[Circulating calcitonin in fulminating purpura in children]. / Calcitonine circulante au cours du purpura fulminans de l'enfant.

Hypocalcaemia may complicate the treatment of fulminating meningococcaemia in children. In an attempt to elucidate the pathophysiology of the hypocalcaemia, we have measured accompanying changes in blood levels of calcitonin (BW-336-6 antiserum) and parathyroid hormone (C-terminal antiserum IRE). Ten children aged 1-11 years with fulminating meningococcaemia are studied. The high PTH levels may be a response to the hypocalcaemia, but the hypercalcitoninaemia seems inappropriate. Provided the immunoreactivity of the calcitonin detected corresponds to calcitonin 1-32, the origin of this hypercalcitoninaemia remains to be explained.