Insights into the subdaily variations in methane, nitrous oxide and carbon dioxide fluxes from upland tropical tree stems.

Recent studies have shown that stem fluxes, although highly variable among trees, can alter the strength of the methane (CH) sink or nitrous oxide (NO) source in some forests, but the patterns and magnitudes of these fluxes remain unclear. This study investigated the drivers of subdaily and seasonal variations in stem and soil CH, NO and carbon dioxide (CO) fluxes. CH, NO and CO fluxes were measured continuously for 19 months in individual stems of two tree species, Eperua falcata (Aubl.

Residual water losses mediate the trade-off between growth and drought survival across saplings of 12 tropical rainforest tree species with contrasting hydraulic strategies.

Knowledge of the physiological mechanisms underlying species vulnerability to drought is critical for better understanding patterns of tree mortality. Investigating plant adaptive strategies to drought should thus help to fill this knowledge gap, especially in tropical rainforests exhibiting high functional diversity. In a semi-controlled drought experiment using 12 rainforest tree species, we investigated the diversity in hydraulic strategies and whether they determined the ability of saplings to use stored non-structural carbohydrates during an extreme imposed drought.

NOVEOS and ImmunoCAP Have Similar Performances for Diagnosing Food Allergies.

Background: The clinical significance of newly available platforms for specific IgE measurement must be evaluated. However, data are lacking for NOVEOS (Hycor), especially for food allergens.

Objective: We compared the technical and clinical performance of two platforms (ImmunoCAP and NOVEOS) to measure specific IgE to 10 food allergens.

Impaired balance between neutrophil extracellular trap formation and degradation by DNases in COVID-19 disease.

Background: Thrombo-inflammation and neutrophil extracellular traps (NETs) are exacerbated in severe cases of COVID-19, potentially contributing to disease exacerbation. However, the mechanisms underpinning this dysregulation remain elusive. We hypothesised that lower DNase activity may be associated with higher NETosis and clinical worsening in patients with COVID-19.

Niche breadth of Amazonian trees increases with niche optimum across broad edaphic gradients.

Understanding how biotic interactions and environmental filtering mediated by soil properties shape plant community assembly is a major challenge in ecology, especially when studying complex and hyperdiverse ecosystems like tropical forests. To shed light on the influence of both factors, we examined how the edaphic optimum of species (their niche position) related to their edaphic range (their niche breadth) along different environmental gradients and how this translates into functional strategies. Here we tested four scenarios describing the shape of the niche breadth-niche position relationship, including one neutral scenario and three scenarios proposing different relative influences of abiotic and biotic factors on community assembly along a soil resource gradient.

Amazon tree dominance across forest strata.

The forests of Amazonia are among the most biodiverse plant communities on Earth. Given the immediate threats posed by climate and land-use change, an improved understanding of how this extraordinary biodiversity is spatially organized is urgently required to develop effective conservation strategies. Most Amazonian tree species are extremely rare but a few are common across the region.

Simultaneous tree stem and soil greenhouse gas (CO , CH , N O) flux measurements: a novel design for continuous monitoring towards improving flux estimates and temporal resolution.

Tree stems and soils can act as sources and sinks for the greenhouse gases (GHG) carbon dioxide (CO ), methane (CH ), and nitrous oxide (N O). Since both uptake and emission capacities can be large, especially in tropical rainforests, accurate assessments of the magnitudes and temporal variations of stem and soil GHG fluxes are required. We designed a new flexible stem chamber system for continuously measuring GHG fluxes in a French Guianese rainforest.

Platelets and IgE: Shaping the Innate Immune Response in Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a systemic and potentially fatal autoimmune disease. SLE pathophysiology is complex and involves the interplay between the innate and adaptive immune systems, with a particularly significant role for type I interferons. Recently, the participation of other actors such as platelets and IgE has been described in SLE.

Pneumonia-Specific Escherichia coli with Distinct Phylogenetic and Virulence Profiles, France, 2012-2014.

In a prospective, nationwide study in France of Escherichia coli responsible for pneumonia in patients receiving mechanical ventilation, we determined E. coli antimicrobial susceptibility, phylotype, O-type, and virulence factor gene content. We compared 260 isolates with those of 2 published collections containing commensal and bacteremia isolates.

Tailoring Empirical Antimicrobial Therapy in Subjects With Ventilator-Associated Pneumonia With a 10-Hour E-Test Approach.

Background: In a previous study of subjects suspected of having ventilator-associated pneumonia, a rapid susceptibility testing approach by using ETEST (BioMérieux) strips directly applied to bronchoalveolar lavage samples provided valuable information at hour 24. The primary objective of this study was to assess a new direct specimen testing by using an even more-rapid E-test approach (at hour 10), which could promote an early de-escalation of the antimicrobial therapy.

Methods: Twenty-eight subjects with ventilator-associated pneumonia admitted to a medical ICU were prospectively included.

Impact of the introduction of a nucleic acid amplification test for diagnosis on stool rejection policies.

Background: The change from non-molecular to nucleic acid amplification tests (NAATs) is known to increase the detection of infection (CDI); however, the impact on stool rejection policies in clinical laboratories is unclear. The current guidelines have reinforced the importance of respecting strict conditions for performing tests on stool samples for CDI diagnosis. The purpose of this study was to estimate whether the implementation of molecular tests has resulted in changes in stool rejection policies between clinical laboratories that introduced NAATs and those that did not.

Reduced inflammation in expanding populations of a neotropical bird species.

The loss of regulating agents such as parasites is among the most important changes in biotic interactions experienced by populations established in newly colonized areas. Under a relaxed parasite pressure, individuals investing less in costly immune mechanisms might experience a selective advantage and become successful colonizers as they re-allocate resources to other fitness-related traits. Accordingly, a refinement of the evolution of increased competitive ability (EICA) hypothesis proposed that immunity of invasive populations has evolved toward a reduced investment in innate immunity, the most costly component of immunity, and an increased humoral immunity that is less costly.

Interaction of Mycoplasma hominis PG21 with Human Dendritic Cells: Interleukin-23-Inducing Mycoplasmal Lipoproteins and Inflammasome Activation of the Cell.

lacks a cell wall, and lipoproteins anchored to the extracellular side of the plasma membrane are in direct contact with the host components. A Triton X-114 extract of enriched with lipoproteins was shown to stimulate the production of interleukin-23 (IL-23) by human dendritic cells (hDCs). The inflammasome activation of the host cell has never been reported upon infection.

There's no place like home: seedling mortality contributes to the habitat specialisation of tree species across Amazonia.

Understanding the mechanisms generating species distributions remains a challenge, especially in hyperdiverse tropical forests. We evaluated the role of rainfall variation, soil gradients and herbivory on seedling mortality, and how variation in seedling performance along these gradients contributes to habitat specialisation. In a 4-year experiment, replicated at the two extremes of the Amazon basin, we reciprocally transplanted 4638 tree seedlings of 41 habitat-specialist species from seven phylogenetic lineages among the three most important forest habitats of lowland Amazonia.

Mycoplasma pneumoniae: Current Knowledge on Macrolide Resistance and Treatment.

Mycoplasma pneumoniae causes community-acquired respiratory tract infections, particularly in school-aged children and young adults. These infections occur both endemically and epidemically worldwide. M.

Clostridium difficile Infection: A Model for Disruption of the Gut Microbiota Equilibrium.

The gut microbiota is a complex ecosystem defined by the combination of microorganisms living in the gastrointestinal tract. Its equilibrium is intimately involved in several aspects of vital process for human physiology and nutrition. Its composition changes depending on both exogenous and endogenous factors.

Surface lipoproteome of Mycoplasma hominis PG21 and differential expression after contact with human dendritic cells.

Aim: To assess the lipoproteins that are involved in the interaction between Mycoplasma hominis and human dendritic cells.

Materials & Methods: The surface lipoproteome of M. hominis PG21 was characterized by using Triton X-114 extraction and LC-MS/MS identification.

Comparison of a novel chemiluminescent based algorithm to three algorithmic approaches for the laboratory diagnosis of Clostridium difficile infection.

Background: Rapid commercial assays, including nucleic acid amplification tests and immunoassays for Clostridium. difficile toxins, have replaced the use of older assays. They are included in a two-step algorithm diagnosis, including first the detection of the glutamate dehydrogenase (GDH) as a screening method and second the detection of toxins as a confirmatory method.

Opportunistic Pulmonary Bordetella hinzii Infection after Avian Exposure.

We report 2 cases of pulmonary Bordetella hinzii infection in immunodeficient patients. One of these rare cases demonstrated the potential transmission of the bacteria from an avian reservoir through occupational exposure and its persistence in humans. We establish bacteriologic management of these infections and suggest therapeutic options if needed.

Prevalence and pathogenicity of binary toxin-positive Clostridium difficile strains that do not produce toxins A and B.

Clostridium difficile causes antibiotic-associated diarrhoea and pseudomembranous colitis. The main virulence factors of C. difficile are the toxins A (TcdA) and B (TcdB).

Experimental evidence for IS1294b-mediated transposition of the blaCMY-2 cephalosporinase gene in Enterobacteriaceae.

Objectives: The objective of this study was to investigate whether the insertion sequence IS1294b (IS91 family) is able to mobilize the blaCMY-2 gene and its adjacent regions from one replicon to another.

Methods: Klebsiella pneumoniae Kp2735 was typed by MLST and its plasmid content was examined by S1-PFGE and PCR-based replicon typing. The genetic blaCMY-2 environment was analysed after cloning experiments and sequencing.