Picoeukaryotes of the Micromonas genus: sentinels of a warming ocean

Photosynthetic picoeukaryotesx in the genus Micromonas show among the widest latitudinal distributions on Earth, experiencing large thermal gradients from poles to tropics. Micromonas comprises at least four different species often found in sympatry. While such ubiquity might suggest a wide thermal niche, the temperature response of the different strains is still unexplored, leaving many questions as for their ecological success over such diverse ecosystems. Using combined experiments and theory, we characterize the thermal response of eleven Micromonas strains belonging to four species. We demonstrate that the variety of specific responses to temperature in the Micromonas genus makes this environmental factor an ideal marker to describe its global distribution and diversity. We then propose a diversity model for the genus Micromonas, which proves to be representative of the whole phytoplankton diversity. This prominent primary producer is therefore a sentinel organism of phytoplankton diversity at the global scale. We use the diversity within Micromonas to anticipate the potential impact of global warming on oceanic phytoplankton. We develop a dynamic, adaptive model and run forecast simulations, exploring a range of adaptation time scales, to probe the likely responses to climate change. Results stress how biodiversity erosion depends on the ability of organisms to adapt rapidly to temperature increase.

Use of a Computer for Compiling and Holding a Medical Thesaurus

A method is described to compile and hold a medical thesaurus through a combination of intellectual effort and the widest possible use of computerization. Various techniques, such as the automatic generation of relationships among terms, are discussed.

Certains suggestions are offered as to the kind of assistance a computer can provide.

Factors Generating Glucose Degradation Products In Sterile Glucose Solutions For Infusion: Statistical Relevance Determination Of Their Impacts

Sterilising glucose solutions by heat promotes the generation of a large number of glucose degradation products (GDPs). It has been shown that high levels of GDPs may result in Advanced Glycation End products that have an impact on cellular homeostasis and health in general. If data is available for peritoneal dialysis solutions, little has been published for glucose infusion fluids. It is essential to identify the parameters causing the formation of GDPs and so limit the risk of exposing patients to them. After quantifying both 5-hydroxymethyl-2-furfural, considered as an important indicator of degradation, and 2-furaldehyde, an ultimate GDP of one degradation pathway, in marketed solutions, the aim of this work is to build a model integrating all the parameters involved in the formation rates of these two GDPs: supplier, glucose amount, container material, oxygen permeability coefficient and time-lapse since manufacture. Our results show a good logarithmic relationship between GDP formation rates and time-lapse since manufacture for both GDPs. The amount of GDPs in the glucose solutions for infusion depends on the initial glucose amount, the polymer of the container, the time elapsed since manufacturing and the supplier.

Revision of the Genus Micromonas Manton et Parke (Chlorophyta, Mamiellophyceae), of the Type Species M. pusilla (Butcher) Manton & Parke and of the Species M. commoda van Baren, Bachy and Worden and Description of Two New Species Based on the Genetic and Phenotypic Characterization of Cultured Isolates

The green picoalgal genus Micromonas is broadly distributed in estuaries, coastal marine habitats and open oceans, from the equator to the poles. Phylogenetic, ecological and genomic analyses of culture strains and natural populations have suggested that this cosmopolitan genus is composed of several cryptic species corresponding to genetic lineages. We performed a detailed analysis of variations in morphology, pigment content, and sequences of the nuclear-encoded small-subunit rRNA gene and the second internal transcribed spacer (ITS2) from strains isolated worldwide. A new morphological feature of the genus, the presence of tip hairs at the extremity of the hair point, was discovered and subtle differences in hair point length were detected between clades. Clear non-homoplasious synapomorphies were identified in the small-subunit rRNA gene and ITS2 spacer sequences of five genetic lineages. These findings lead us to provide emended descriptions of the genus Micromonas, of the type species M. pusilla, and of the recently described species M. commoda, as well as to describe 2 new species, M. bravo and M. polaris. By clarifying the status of the genetic lineages identified within Micromonas, these formal descriptions will facilitate further interpretations of large-scale analyses investigating ecological trends in time and space for this widespread picoplankter.

[Impact of education program and clinical posting in psychiatry on medical students' stigmatizing attitudes towards psychiatry and psychiatric disorders]

OBJECTIVE

The aim of the study was to explore whether a medical student education program and clinical posting in psychiatry had an impact on medical students' stigmatizing attitudes towards psychiatry and psychiatric disorders.

METHODS

Medical students from the University of Bordeaux were recruited during their 4-year course at the beginning of the academic education program in psychiatry. Medical students who were concomitantly in a clinical posting in wards of psychiatry or neurology were invited to participate in the study. The medical student version of the scale Mental Illness: Clinicians' Attitudes (MICA) was used to measure their attitudes towards psychiatry and persons with psychiatric disorder. This 16-item scale is designed to measure attitudes of health care professionals towards people with mental illness, a higher score indicating more stigmatizing attitudes. Items exploring history of psychiatric disorders in close persons were added at the end of the MICA scale. The questionnaire was completed twice by each student, at the beginning and the end of the 11-week clinical posting. All questionnaires were strictly anonymized. Multivariate linear regression analyses were used to identify the variables independently associated with MICA total score.

RESULTS

At the beginning of the education program and clinical posting, 174 students completed the MICA scale: the mean MICA total score was equal to 46.4 (SD 6.9) in students in clinical posting in psychiatry (n=72) and 45.1 (SD 7.01) in those in neurology (n=102). At the end of the academic and clinical training, 138 students again completed the questionnaire, with mean MICA total scores equal to 41.4 (SD 8.1) in students in clinical posting in psychiatry (n=51) and 43.5 (SD 7.3) in those in neurology (n=87). Multivariate analyses showed that lower total MICA scores were independently associated with the time of assessment (lower scores at the end of education program and clinical posting) (b=-2.8; P=0.001), female gender (b=-1.8; P=0.03) and history of a psychiatric disorder in a close person (b=-1.92; P=0.02). Type of clinical posting (psychiatry vs. neurology) was not independently associated with MICA total scores (b=-0.02; P=0.98). A significant interaction was found between the variables "time of assessment" and "type of clinical posting" (P=0.05): stratified analyses showed that MICA total scores decreased significantly only when the clinical posting was in psychiatry (b=-4.66; P=0.001), with no significant change in medical students in neurology wards (b=-1.45; P=0.16).

CONCLUSION

Stigmatizing attitudes of medical students towards psychiatry and psychiatric disorders are reduced by an education program in psychiatry, with a positive impact more marked when the education program is concomitant to a clinical posting in psychiatry. As future health professionals in charge of persons with psychiatric disorders, medical students are key targets of actions aimed at reducing stigma towards mental health disorders. It is hence of great importance to promote clinical training in psychiatric wards during medical studies for all future practitioners, irrespective of their future specialty.

Temperature is a key factor in Micromonas-virus interactions

The genus Micromonas comprises phytoplankton that show among the widest latitudinal distributions on Earth, and members of this genus are recurrently infected by prasinoviruses in contrasted thermal ecosystems. In this study, we assessed how temperature influences the interplay between the main genetic clades of this prominent microalga and their viruses. The growth of three Micromonas strains (Mic-A, Mic-B, Mic-C) and the stability of their respective lytic viruses (MicV-A, MicV-B, MicV-C) were measured over a thermal range of 4-32.5 °C. Similar growth temperature optima (T_opt) were predicted for all three hosts but Mic-B exhibited a broader thermal tolerance than Mic-A and Mic-C, suggesting distinct thermoacclimation strategies. Similarly, the MicV-C virus displayed a remarkable thermal stability compared with MicV-A and MicV-B. Despite these divergences, infection dynamics showed that temperatures below T_opt lengthened lytic cycle kinetics and reduced viral yield and, notably, that infection at temperatures above T_opt did not usually result in cell lysis. Two mechanisms operated depending on the temperature and the biological system. Hosts either prevented the production of viral progeny or maintained their ability to produce virions with no apparent cell lysis, pointing to a possible switch in the viral life strategy. Hence, temperature changes critically affect the outcome of Micromonas infection and have implications for ocean biogeochemistry and evolution.

Analysis of plasticizers in PVC medical devices: Performance comparison of eight analytical methods

A wide variety of medical devices (MDs) used in hospitals are made of flexible plasticized polyvinylchloride (PVC). Different plasticizers are present in variable amounts in the PVC matrix of the devices and can leach out into the infused solutions and may enter into contact with the patients. The ARMED¹ project aims to assess the migration of these plasticizers from medical devices and therefore the level of exposure in patients. For the first task of the project, eight methods were developed to directly detect and quantify the plasticizers in the PVC matrix of the MDs. We compared the overall performances of the analytical methods using standardized and validated criteria in order to provide the scientific community with the guidance and the technical specifications of each method for the intended application. We have shown that routine rapid screening could be performed directly on the MDs using the FTIR technique, with cost-effective analyses. LC techniques may also be used, but with limits and only with individual quantification of the main plasticizers expected in the PVC matrix. GC techniques, especially GC-MS, are both more specific and more sensitive than other techniques. NMR is a robust and specific technique to precisely discriminate all plasticizers in a MD but is limited by its cost and its low ability to detect and quantify plasticizer contamination, e.g. by DEHP. All these results have been confirmed by a real test, called the " blind test " carried out on 10 MD samples.

Benthic protists: the under-charted majority

Marine protist diversity inventories have largely focused on planktonic environments, while benthic protists have received relatively little attention. We therefore hypothesize that current diversity surveys have only skimmed the surface of protist diversity in marine sediments, which may harbor greater diversity than planktonic environments. We tested this by analyzing sequences of the hypervariable V4 18S rRNA from benthic and planktonic protist communities sampled in European coastal regions. Despite a similar number of OTUs in both realms, richness estimations indicated that we recovered at least 70% of the diversity in planktonic protist communities, but only 33% in benthic communities. There was also little overlap of OTUs between planktonic and benthic communities, as well as between separate benthic communities. We argue that these patterns reflect the heterogeneity and diversity of benthic habitats. A comparison of all OTUs against the Protist Ribosomal Reference database showed that a higher proportion of benthic than planktonic protist diversity is missing from public databases; similar results were obtained by comparing all OTUs against environmental references from NCBI's Short Read Archive. We suggest that the benthic realm may therefore be the world's largest reservoir of marine protist diversity, with most taxa at present undescribed.

Measles outbreak in a refugee settlement in Calais, France: January to February 2016

We report a measles outbreak in a refugee settlement in Calais, France, between 5 January and 11 February 2016. In total, 13 confirmed measles cases were identified among migrants, healthcare workers in hospital and volunteers working on site. A large scale vaccination campaign was carried out in the settlement within two weeks of outbreak notification. In total, 60% of the estimated target population of 3,500 refugees was vaccinated during the week-long campaign.