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The juxtaposition of highly productive coral reef ecosystems in oligotrophic waters has spurred substantial interest and progress in our understanding of macronutrient uptake, exchange, and recycling among coral holobiont partners (host coral, dinoflagellate endosymbiont, endolithic algae, fungi, viruses, bacterial communities). By contrast, the contribution of trace metals to the physiological performance of the coral holobiont and, in turn, the functional ecology of reef-building corals remains unclear. The coral holobiont's trace metal economy is a network of supply, demand, and exchanges upheld by cross-kingdom symbiotic partnerships. Each partner has unique trace metal requirements that are central to their biochemical functions and the metabolic stability of the holobiont. Organismal homeostasis and the exchanges among partners determine the ability of the coral holobiont to adjust to fluctuating trace metal supplies in heterogeneous reef environments. This review details the requirements for trace metals in core biological processes and describes how metal exchanges among holobiont partners are key to sustaining complex nutritional symbioses in oligotrophic environments. Specifically, we discuss how trace metals contribute to partner compatibility, ability to cope with stress, and thereby to organismal fitness and distribution. Beyond holobiont trace metal cycling, we outline how the dynamic nature of the availability of environmental trace metal supplies can be influenced by a variability of abiotic factors (e.g. temperature, light, pH, etc.). Climate change will have profound consequences on the availability of trace metals and further intensify the myriad stressors that influence coral survival. Lastly, we suggest future research directions necessary for understanding the impacts of trace metals on the coral holobiont symbioses spanning subcellular to organismal levels, which will inform nutrient cycling in coral ecosystems more broadly. Collectively, this cross-scale elucidation of the role of trace metals for the coral holobiont will allow us to improve forecasts of future coral reef function.

Our aim was to determine the rate of success of HFNO and its relationship with current treatments for severe COVID-19.This was a cohort study including patients admitted for HFNO because of respiratory failure despite oxygen therapy through a facial mask. Care was standardized, with systematic use of steroids and prevention or treatment of thromboembolic complications, and tocilizumab when deemed useful. HFNO failure was defined by the requirement for mechanical ventilation and/or death.In August 2021, among 1397 patients with COVID-19 admitted in the emergency department, 110 (7.8%) received HFNO (mean age 55 years, sex-ratio M/F 1.4). Thirteen patients (12%) had received a steroid treatment before hospital admission. At least one comorbid condition was observed in 57% of the patients. Mean duration of the disease at admission was 8.8 days and mean respiratory rate was 34/min. A CT scan was performed for 101 patients (92%), among whom 13 had a pulmonary embolism. All patients received a steroid treatment, and tocilizumab was prescribed in 79 cases (72%). Failure of HFNO was observed in 54 cases (49%); the only risk factor was the absence of tocilizumab administration: AOR [IC95%] 3.50 [1.40-8.69]. We observed a trend toward failure with steroid use before hospital admission: AOR 3.83 [0.96-16.66].Success of HFNO, when all therapeutic means of treatment for severe COVID-19 pneumonia were applied, was associated with tocilizumab administration. Our data suggest the interest of a randomized study to determine whether HFNO is the right signal for prescription of anti-IL6 drugs.

Teleconsultation is an emerging tool whose utilization dramatically increased during the Covid-19 pandemic. Our aim was to determine its clinical accuracy.This prospective study was carried out during the first wave of Covid-19. Patients were teleconsulted by either general practitioners or emergency doctors reporting clinical exam results to the ID physicians by phone. Five signs were specifically checked: dyspnea, fever, cough, anosmia and flu-like illness. Data collected by remote consultation were compared to face-to-face examination in an ID Department.From March to April 2020, 149 patients were seen by remote medical care. Dyspnea was found in 14.1% of the teleconsultation patients vs 3.4% in face-to-face consultation; fever in 47.0 vs. 15.4%; cough in 69.1 vs. 16.1%; anosmia in 3.4 vs. 1.3%; flu-like illness in 53.0 vs. 7.4% (all differences significant: P0.001).We observed incongruency between remote and face-to-face consultation for the main clinical signs of Covid-19.

The application of established cell viability assays such as the commonly used trypan blue staining method to coral cells is not straightforward due to different culture parameters and different cellular features specific to mammalian cells compared to marine invertebrates. Using Pocillopora damicornis as a model, we characterized the autofluorescence and tested different fluorescent dye pair combinations to identify alternative viability indicators. The cytotoxicity of different representative molecules, namely small organic molecules, proteins and nanoparticles (NP), was measured after 24 h of exposure using the fluorescent dye pair Hoechst 33342 and SYTOX orange. Our results show that this dye pair can be distinctly measured in the presence of fluorescent proteins plus chlorophyll. P. damicornis cells exposed for 24 h to Triton-X100, insulin or titanium dioxide (TiO2) NPs, respectively, at concentrations ranging from 0.5 to 100 µg/mL, revealed a LC50 of 0.46 µg/mL for Triton-X100, 6.21 µg/mL for TiO2 NPs and 33.9 µg/mL for insulin. This work presents the approach used to customize dye pairs for membrane integrity-based cell viability assays considering the species- and genotype-specific autofluorescence of scleractinian corals, namely: endogenous fluorescence characterization followed by the selection of dyes that do not overlap with endogenous signals.

The breakdown of symbiotic mutualism between cnidarian hosts and dinoflagellate algae partners (i.e., bleaching) has been linked to an immune-like response pathway brought on by a nitro-oxidative burst, a symptom of thermal stress. Stress induced by reactive oxygen species (ROS)/reactive nitrogen species is a problem common to aerobic systems. In this study, we tested the antioxidant effects of engineered poly(acrylic acid)-coated cerium dioxide nanoparticles (CeO2, nanoceria) on free-living Symbiodiniaceae (Breviolum minutum), a dinoflagellate alga that forms symbiotic relationships with reef-building corals and anemones. Results show that poly(acrylic acid)-coated CeO2 with hydrodynamic diameters of ~4 nm are internalized by B. minutum in under 30 min and subsequently localized in the cytosol. Nanoceria exposure does not inhibit cell growth over time, with the treated cultures showing a similar growth trend over the 25-day exposure. Aerobic activity and thermal stress when held at 34°C for 1 h (+6°C above control) led to increased intracellular ROS concentration with time. A clear ROS scavenging effect of the nanoceria was observed, with a 5-fold decrease in intracellular ROS levels during thermal stress. The nitric oxide (NO) concentration decreased by ~17% with thermal stress, suggesting the rapid involvement of NO scavenging enzymes or proteins within 1 h of stress onset. The presence of nanoceria did not appear to influence NO concentration. Furthermore, aposymbiotic anemones (Exaiptasia diaphana, ex Aiptasia pallida) were successfully infected with nanoceria-loaded B. minutum, demonstrating that inoculation could serve as a delivery method. The ability of nanoceria to be taken up by Symbiodiniaceae and reduce ROS production could be leveraged as a potential mitigation strategy to reduce coral bleaching.

BackgroundTraining in psychiatry requires specific knowledge, attitudes, and skills that are obtainable by simulation, of which the use is only recent and still needs further development. Evidence is accumulating on its effectiveness but requires further validation for medical students. We aimed to evaluate the effectiveness of a single-day optional teaching program in psychiatry by simulation for medical students and validate a scale measuring Confidence in Psychiatric Clinical Skills (CPCQ), as part of the assessment.MethodsThis was a controlled study in a French University that compared (using paired-sample Student t-tests) knowledge and attitudes (university grades and CPCQ scores) before, just after teaching with simulated patients, and 2 months later. Satisfaction with the program (including the quality of the debriefing) was also investigated. The CPCQ scale was validated by assessing the factor structure, internal consistency, and test-retest reliability. Finally, a comparison was run with a control group who received the usual psychiatric instruction using covariance analyses.ResultsTwenty-four medical students were included in the simulation group and 76 in the control group. Just after the simulation, knowledge and attitudes increased significantly in the simulation group. Satisfaction with the training and debriefing was very high. The CPCQ scale showed good psychometric properties: a single-factor structure, acceptable internal consistency (α = 0.73 [0.65–0.85]), and good test-retest reliability (ICC = 0.71 [0.35–0.88]). Two months after the simulation, knowledge and attitudes were significantly higher in the simulation group than the control group, despite a lack of difference in knowledge before the simulation.ConclusionsAdding a simulation program in psychiatry to the usual teaching improved the knowledge and confidence of medical students. The CPCQ scale could be used for the evaluation of educational programs.

The application of established cell viability assays such as the commonly used trypan blue staining method to coral cells is not straightforward due to different culture parameters and different cellular features specific to mammalian cells compared to marine invertebrates. Using Pocillopora damicornis as a model, we characterized the autofluorescence and tested different fluorescent dye pair combinations to identify alternative viability indicators. The cytotoxicity of different representative molecules, namely small organic molecule, protein and nanoparticles (NP), was measured after 24 hours of exposure using the fluorescent dye pair Hoechst 33342 and SYTOX® orange. Our results show that this dye pair can be distinctly measured in the presence of fluorescent proteins plus chlorophyll. P. damicornis cells exposed for 24 hours to Triton-X100, insulin or titanium dioxide (TiO2) NPs, respectively, at concentrations ranging from 0.5-100 µg/mL, revealed a LC50 of 0.5 µg/mL for Triton-X100, 20 µg/mL for TiO2 NPs and an average 20% reduction in viability at 100 µg/mL for insulin. The workflow presented here provides a general framework for customizing dye pairs for cell viability assays considering the species- and genotype-specific autofluorescence of scleractinian corals.

Environment stress is a major threat to the existence of coral reefs and has generated a lot of interest in the coral research community. Under the environmental stress, corals can experience tissue loss and/or the breakdown of symbiosis between the cnidarian host and its symbiotic algae causing the coral tissue to appear white as the skeleton can be seen by transparency. Image analysis is a common method used to assess tissue response under the environmental stress. However, the traditional approach is limited by the dynamic nature of the coral-algae symbiosis. Here, we observed coral tissue response in the scleractinian coral, Montipora capricornis, using high frequency image analysis throughout the experiment, as opposed to the typical start/end point assessment method. Color analysis reveals that the process can be divided into five stages with two critical stages according to coral tissue morphology and color ratio. We further explore changes to the morphology of individual polyps by means of the Pearson correlation coefficient and recurrence plots, where the quasi-periodic and nonstationary dynamics can be identified. The recurrence quantification analysis also allows the comparison between the different polyps. Our research provides a detailed visual and mathematical analysis of coral tissue response to environmental stress, which potentially shows universal applicability. Moreover, our approach provides a robust quantitative advancement for improving our insight into a suite of biotic responses in the perspective of coral health evaluation and fate prediction.

With the ease of gene sequencing and the technology available to study and manipulate non-model organisms, the extension of the methodological toolbox required to translate our understanding of model organisms to non-model organisms has become an urgent problem. For example, mining of large coral and their symbiont sequence data is a challenge, but also provides an opportunity for understanding functionality and evolution of these and other non-model organisms. Much more information than for any other eukaryotic species is available for humans, especially related to signal transduction and diseases. However, the coral cnidarian host and human have diverged over 700 million years ago and homologies between proteins in the two species are therefore often in the gray zone, or at least often undetectable with traditional BLAST searches. We introduce a two-stage approach to identifying putative coral homologues of human proteins. First, through remote homology detection using Hidden Markov Models, we identify candidate human homologues in the cnidarian genome. However, for many proteins, the human genome alone contains multiple family members with similar or even more divergence in sequence. In the second stage, therefore, we filter the remote homology results based on the functional and structural plausibility of each coral candidate, shortlisting the coral proteins likely to have conserved some of the functions of the human proteins. We demonstrate our approach with a pipeline for mapping membrane receptors in humans to membrane receptors in corals, with specific focus on the stony coral, P. damicornis. More than 1000 human membrane receptors mapped to 335 coral receptors, including 151 G protein coupled receptors (GPCRs). To validate specific sub-families, we chose opsin proteins, representative GPCRs that confer light sensitivity, and Toll-like receptors, representative non-GPCRs, which function in the immune response, and their ability to communicate with microorganisms. Through detailed structure-function analysis of their ligand-binding pockets and downstream signaling cascades, we selected those candidate remote homologues likely to carry out related functions in the corals. This pipeline may prove generally useful for other non-model organisms, such as to support the growing field of synthetic biology.

BACKGROUND For several years, we applied an internal guideline for community-acquired urinary tract infections (cUTI), targeting the reduction of fluoroquinolone use (FQ) and thereby favouring cotrimoxazole (CTM) prescription. Our aim was to report adverse effects (AE) and outcome for patients presenting with cUTI and treated with these compounds. METHODS This cohort study was based on the dashboard of our department, bringing together 28 parameters for all patients, including diagnosis, microbiological data, antibiotic therapy, AE, length of hospital stay (LHS) and outcome. We included all patients with cUTI due to Enterobacteriaeae treated with CTM or FQ, and compared these 2 groups on in-hospital AE, LHS, and unfavourable outcome defined as intensive care requirement or death. RESULTS From June 2008 to June 2019, 640 cUTI due to Enterobacteriaeae were observed, among which 295 (46%) treated with CTM and 345 (54%) with a FQ. There were 25 AE (3.9%): 17 (5.7%) in the CTM group, and 8 (2.3%) in the FQ group (P=0.025). Adverse effects were associated with increased LHS compared to patients without AE: 11±6 vs. 7±4 days respectively, P

This protocol was designed to detect acellular oxidative reactivity of nanoparticles

The Covid-19 pandemic is the major global health crisis of our time. The purpose of this study is to estimate the seroprevalence of IgG against SARS-CoV-2 among workers in the University Hospi-tal of Guadeloupe and to assess this seroprevalence in asymptomatic personnel as well as the proportion of asymptomatic agents among seropositive agents.We carried out a seroprevalence study in the staff of the University Hospital of Guadeloupe. The presence of IgG anti SARS-CoV-2 was determined by a micro-particulate immunolo-gical assay using the chemiluminescence technique (CMIA, Architect i2000SR, Abbott). Data on the previous presence of symptoms sugge-stive of COVID-19, were identified using a standardized questionnaire. Statistical analyses were performed using Epi Info® software.From 07/05/2020 to 28/10/2020, 892 serologies were performed, 45 of which were positive for SARS-CoV-2 : a prevalence of 5.0% [95% CI: 3.6% - 6.5%]. Seroprevalence was 1.5% [95% CI: 0.6% - 2.3%] among agents who reported being asymptomatic. Among seropositive individuals, 24.4% [95% CI:12% - 36%] was totally asymptomatic.Our results highlight the importance of continuing seroprevalence studies for SARS-CoV-2 in hospital staff, which can provide important information on the level of exposure in healthcare workers and asymptomatic transmission of SARS-CoV-2 in clinical set-tings.

Background: Household health-seeking behaviour for malaria treatment is an important policy concern in malaria-endemic African countries. This paper aims to shed light on the determinants of household’s health-seeking behaviour for malaria treatment in Cameroon.Methods: The cross-sectional study used secondary data from the fourth Cameroonian household consumption survey conducted by the National Institute of Statistics. A stratified, 2-stage sampling was implemented with a sample of 918 households which sought malaria treatment from different alternatives providers. The multinomial probit model was used to estimate the probability based on socio-demographic and economics determinants for a household to choose between different types of providers of malaria treatment.Results: The findings of this study indicate that, the alternative providers for malaria treatment were: public health facilities (61.1%), private health facilities (8.5%), traditional healers (1.4%), pharmacies (4.6%), informal vendor (18%), other types of recourse (6.4%). The decision to choose the provider for malaria treatment depends on factors such as household head, region, level of education, religion, area of residence, socio-professional category, and gender. The level of education appears to be an important determinant of a household’s seeking behaviour. Those with higher education are more likely to seek care at formal health facilities.Conclusions: Health policy-makers need to strive to improve the socio-demographic and economic conditions and sensitize households on the appropriate alternative ways to ensure the universal access to diagnosis and effective treatment of malaria in line with the global strategies recommended by WHO to achieve malaria elimination by 2030.

Time-Domain Nuclear Magnetic Resonance (TD-NMR) was used to quantify the lipid contents of 48 different organic waste substrates. Results obtained from TD-NMR were compared to those from Soxhlet extraction, currently the prevalent method for organic waste characterization, especially in the field of anaerobic digestion. Two calibration methods were tested. The first was a self-calibration process using pure oils (NMR1) which showed good repeatability compared to Soxhlet extraction with a better coefficient of variation (5%). Analyses of volatile fatty acids (VFA) and long-chain fatty acids (LCFA) by chromatography were carried out to understand why the NMR1 method produced underestimations for some samples. Statistical analysis showed that the presence of saturated fatty acids had a significant effect on differences between the Soxhlet and NMR1 methods. The second calibration method applied chemometrics to TD-NMR raw data (NMR2), taking Soxhlet extraction values as references. It provided a good prediction of lipid content and avoided the lengthy calibration procedure usually required for this type of study. Last, the NMR2 method was shown to be highly suited to the quantification of lipids in organic waste, demonstrating better repeatability than the classic Soxhlet method.

2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) is a popular fluorescent probe for the detection of oxidative stress in cells. Since the probe can be prone to auto-oxidation, carboxy-2',7'-dichlorodihydrofluorescein-diacetate (carboxy-H2DCF-DA) which is more stable and easily penetrates cell membranes is often reported in the literature instead. Upon crossing the cell membrane, esterases hydrolyse DCFH-DA to DCFH, which remains trapped within cells. The oxidation of DCFH yields DCF, a fluorescent compound which can be measured using excitation/emission wavelengths of 485-495/520-530 nm. Due to several cases of interference when used in cellular systems, DCFH-DA is a general marker of the cellular oxidative stress rather than a specific indicator H2O2 formation or other ROS.

Diaminofuorescein-2 diacetate (DAF-2 DA) is a fluorescent indicator of nitric oxide (NO). The DAF reacts with the nitric anhydride (N2O3) which formed by oxidation of NO. Upon crossing the cell membrane, esterases hydrolyse DAF-2 DA to DAF-2, which remains trapped within cells. The DAF-2 reacts to the oxidation of intracellular NO (or more accurately the N2O3) to produce the highly fluorescent triazolofluorescein (DAF-2T) by nitrosation and dehydration (Kojima et al., 1999). Protocol adapted from Bouchard & Yamasaki (2009) and Kojima et al. (1999)

Background The reproducibility of gene expression measured by RNA sequencing (RNA-Seq) is dependent on the sequencing depth. While unmapped or non-exonic reads do not contribute to gene expression quantification, duplicate reads contribute to the quantification but are not informative for reproducibility. We show that mapped, exonic, non-duplicate (MEND) reads are a useful measure of reproducibility of RNA-Seq datasets used for gene expression analysis. Findings In bulk RNA-Seq datasets from 2,179 tumors in 48 cohorts, the fraction of reads that contribute to the reproducibility of gene expression analysis varies greatly. Unmapped reads constitute 1–77% of all reads (median [IQR], 3% [3–6%]); duplicate reads constitute 3–100% of mapped reads (median [IQR], 27% [13–43%]); and non-exonic reads constitute 4–97% of mapped, non-duplicate reads (median [IQR], 25% [16–37%]). MEND reads constitute 0–79% of total reads (median [IQR], 50% [30–61%]). Conclusions Because not all reads in an RNA-Seq dataset are informative for reproducibility of gene expression measurements and the fraction of reads that are informative varies, we propose reporting a dataset's sequencing depth in MEND reads, which definitively inform the reproducibility of gene expression, rather than total, mapped, or exonic reads. We provide a Docker image containing (i) the existing required tools (RSeQC, sambamba, and samblaster) and (ii) a custom script to calculate MEND reads from RNA-Seq data files. We recommend that all RNA-Seq gene expression experiments, sensitivity studies, and depth recommendations use MEND units for sequencing depth.

Temperatures approaching or exceeding 20°C have been measured during summer in polar regions at the surfaces of barren fellfield soils under cloudless skies around solar noon. However, despite the upper temperature limit for the growth of cold‐adapted microbes—which are abundant in polar soils and have pivotal roles in nutrient cycling—typically being close to this temperature, previous studies have not addressed the consequences of climate change for the metabolism of these organisms in the natural environment. Here in a 5‐year field experiment on Alexander Island in the southern maritime Antarctic, we show that the abundance of Pseudogymnoascus roseus, the most widespread decomposer fungus in maritime Antarctic fellfield soils, is reduced by 1–2 orders of magnitude when irrigated and nutrient‐amended soils are warmed to >20°C during summer. Laboratory experiments under conditions mimicking those during midsummer in the natural environment indicated that the hyphal extension rates of P. roseus isolates and the activities of five extracellular enzymes are reduced by 54%–96% at high water availability after exposure to temperatures cycling daily from 2 to 21°C and 2 to 24°C, relative to temperatures cycling from 2 to 18°C. Given that the temperatures of surface soils at the study site already reach 19°C during midsummer, the observations reported here suggest that, at predicted rates of warming arising from moderate greenhouse gas emissions, inhibitory effects of climate change on the metabolism of P. roseus could manifest themselves within the next few decades. Furthermore, with peak temperatures at the surfaces of fellfield soils at other maritime Antarctic locations and in High Arctic and alpine regions already exceeding 20°C during summer, the observations suggest that climate warming has the potential to inhibit the growth of other cold‐adapted microbes, with negative effects on soils as the Earth's climate continues to warm., Summertime temperatures at the surfaces of barren maritime Antarctic soils can approach or exceed 20°C under cloudless skies around solar noon. Here we show that the metabolism of the cold‐adapted and widespread Antarctic soil fungus Pseudogymnoascus roseus is inhibited when it is exposed to temperatures cycling daily to more than 20°C, both in the natural environment and the laboratory, with substantial reductions in the in vitro growth rates of colonies and activities of extracellular enzymes. We propose that surface warming in cold regions has the potential to inhibit the growth of other cold‐adapted microbes, with negative effects on soils as the Earth's climate continues to warm.