Publications by authors named "Maitre A"

A coherent concatenation of multiple solitary waves may lead to a stable infrared and visible broadband filament in a ceramic YAG polycrystal. This self-trapped soliton train is leveraged to implement self-referenced multiplex coherent anti-Stokes Raman scattering (SR-M-CARS) imaging. Simulations and experiments illustrating the filamentation process and the concatenation of focusing-defocusing cycles in ceramic and crystal YAG are presented.

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The Western honey bee () is a vital agricultural pollinator whose populations are threatened by the parasitic mite destructor and associated pathogens. While the impact of species on honey bees, particularly larvae causing American foulbrood, is documented, their effect on the microbiota of mites remains unclear. This study aimed to investigate the influence of sp.

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Article Synopsis
  • Mosquitoes are important vectors for diseases, making it essential to understand their microbiota to improve disease management strategies.
  • The study found distinct microbial compositions and interaction patterns between two mosquito species, Culex pipiens f. molestus and Culex quinquefasciatus, with Escherichia-Shigella being more widespread and interacting with many network nodes in both species, while Wolbachia showed species-specific associations.
  • Computer simulations demonstrated that the removal of microorganisms impacted network stability differently in the two species, indicating the unique role of each bacterium in maintaining microbial networks.
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Boron carbide (BC) possesses a large potential as a structural material owing to its lightness, refractory character, and outstanding mechanical properties. However, its large-scale industrialization is set back by its tendency to amorphize when subjected to an external stress. In the present work, we design a path toward nanostructured boron carbide with greatly enhanced hardness and resistance to amorphization.

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An infection with the tick-borne has been associated with a broad spectrum of clinical manifestations in humans, but patients are only seldomly reported. Understanding its disease etiology necessitates well-stablished infection models, improving to recognize and diagnose patients with infection and facilitating the development of effective control strategies. In this study, we used C3H/HeN mice as a model to establish infection, achieving a high infection prevalence (89-100 %).

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Evolutionary convergence in distantly related species is among the most convincing evidence of adaptive evolution. The mammalian ear, responsible for balance and hearing, is not only characterised by its spectacular evolutionary incorporation of several bones of the jaw, it also varies considerably in shape across modern mammals. Using a multivariate approach, we show that in Afrotheria, a monophyletic clade with morphologically and ecologically highly disparate species, inner ear shape has evolved similar adaptations as in non-afrotherian mammals.

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Article Synopsis
  • - This study builds on previous research about how antibiotics affect the tick microbiota, particularly the transmission of Babesia microti, by comparing antibiotic-treated (AT) and control-treated (CT) Haemaphysalis longicornis ticks to observe changes in their microbial community interactions.
  • - Results indicated that AT ticks had a more connected but less interactive microbial community, showing significant differences in network centrality measures, which reflect how different bacteria interact within the community.
  • - The findings highlight that certain bacteria like Coxiella and Acinetobacter play key roles in maintaining network stability, and the antibiotic treatment made these networks less robust, indicating a higher susceptibility to disturbances.
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Tick-borne rickettsioses, caused by Gram-negative bacteria of the Rickettsia genus, pose a growing global threat, with various arthropod vectors contributing to their transmission. Understanding the complex interactions within tick microbiota, including the role of Rickettsia species, is crucial for elucidating the dynamics of rickettsial diseases. Here, we investigate the taxonomic profiles and co-occurrence networks of Rickettsia in Rh.

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The honeybee (Apis mellifera) is a key pollinator critical to global agriculture, facing threats from various stressors, including the ectoparasitic Varroa mite (Varroa destructor). Previous studies have identified shared bacteria between Varroa mites and honeybees, yet it remains unclear if these bacteria assemble similarly in both species. This study builds on existing knowledge by investigating co-occurrence patterns in the microbiomes of both Varroa mites and honeybees, shedding light on potential interactions.

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The Ornithodoros moubata (Om) soft tick, a vector for diseases like tick-borne human relapsing fever and African swine fever, poses challenges to conventional control methods. With diminishing insecticide efficacy, harnessing the tick's microbiota through innovative approaches like microbiota-driven vaccination emerges as a promising strategy for sustainable and targeted disease control. This study investigated the intricate relationship between Pseudomonas, a keystone taxon in the Om microbiome, and its impact on tick fitness, microbiome structure and network dynamics.

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The innovation introduced in this study consists of replacing toluene with safer solvents such as cyclopentane or diethyl ether in the processing of a preceramic polycarbosilane (allylhydridopolycarbosilane, AHPCS) and assessing its impact on the functionalisation of BC powders to produce BC/SiC composites. Fourier-transform infrared (FT-IR) with ATR and nuclear magnetic resonance (NMR) spectroscopy revealed no major modification in the polymer structure. SEC/MALS analysis showed a slight change in the number-average molar mass of the polymer regardless of the functionalisation solvent used in correlation with a slight decrease in the polymer ceramic yield due to oligomer loss.

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Understanding the intricate ecological interactions within the microbiome of arthropod vectors is crucial for elucidating disease transmission dynamics and developing effective control strategies. In this study, we investigated the ecological roles of Coxiella-like endosymbiont (CLE) and Anaplasma marginale across larval, nymphal, and adult stages of Rhipicephalus microplus. We hypothesized that CLE would show a stable, nested pattern reflecting co-evolution with the tick host, while A.

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Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants of significant public health concern, with several that are highly toxic to humans, including some proven or suspected carcinogens. To account for the high variability of PAH mixtures encountered in occupational settings, adjusting urinary 1-hydroxypyrene (1-OHP) levels by the total airborne pyrene (PyrT)/benzo[a]pyrene (BaP) ratio is essential for human biomonitoring (HBM). Given the complexity and cost of systematically monitoring atmospheric levels, alternative approaches to simultaneous airborne and HBM are required.

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Breast cancer, a global health concern affecting women, has been linked to alterations in the gut microbiota, impacting various aspects of human health. This study investigates the interplay between breast cancer and the gut microbiome, particularly focusing on colonization resistance-an essential feature of the microbiota's ability to prevent pathogenic overgrowth. Using a mouse model of breast cancer, we employ diversity analysis, co-occurrence network analysis, and robustness tests to elucidate the impact of breast cancer on microbiome dynamics.

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Upon ingestion from an infected host, tick-borne pathogens (TBPs) have to overcome colonization resistance, a defense mechanism by which tick microbiota prevent microbial invasions. Previous studies have shown that the pathogen alters the microbiota composition of the nymphs of , but its impact on tick colonization resistance remains unclear. We analyzed tick microbiome genetic data using published Illumina 16S rRNA sequences, assessing microbial diversity within ticks (alpha diversity) through species richness, evenness, and phylogenetic diversity.

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Article Synopsis
  • Jingmen tick virus (JMTV) is a segmented RNA virus discovered in 2014, linked to febrile illnesses in humans, and found in various species and environments globally.
  • Researchers developed a RT-qPCR assay to detect these viruses in ticks, testing its effectiveness on samples collected from livestock in Corsica, France.
  • The study reports the first detection of JMTV in Corsican ticks, revealing a significant genetic similarity to strains found in human patients elsewhere, highlighting the island's potential role in future epidemic monitoring.
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Interactions within the tick microbiome involving symbionts, commensals, and tick-borne pathogens (TBPs) play a pivotal role in disease ecology. This study explored temporal changes in the microbiome of , an important cattle tick vector, focusing on its interaction with . To overcome limitations inherent in sampling methods relying on questing ticks, which may not consistently reflect pathogen presence due to variations in exposure to infected hosts in nature, our study focused on ticks fed on chronically infected cattle.

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Avian malaria infection has been known to affect host microbiota, but the impact of infection on the colonization resistance in bird gut microbiota remains unexplored. This study investigated the dynamics of infection in canaries, aiming to explore the hypothesis that microbiota modulation by would reduce colonization resistance. Canaries were infected with , while a control group was maintained.

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Context: Pathogens can manipulate microbial interactions to ensure survival, potentially altering the functional patterns and microbiome assembly. The present study investigates how Anaplasma phagocytophilum infection affects the functional diversity, composition, and assembly of the Ixodes scapularis microbiome, with a focus on high central pathways-those characterized by elevated values in centrality metrics such as eigenvector, betweenness, and degree measures, in the microbial community.

Methods: Using previously published data from nymphs' gut V4 region's amplicons of bacterial 16S rRNA, we predicted the functional diversity and composition in control and A.

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Recent studies show that mosquito-microbiota interactions affects vector competence and fitness. We investigated if host antibodies modifying microbiota impact mosquito physiology. We focused on three prevalent bacteria (Acinetobacter, Pantoea, and Chryseobacterium), originally isolated from the Asian tiger mosquito Aedes albopictus.

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The gut microbiota plays a crucial role in animal health and homeostasis, particularly in endangered species conservation. This study investigated the fecal microbiota composition of European captive-bred African savanna elephants () housed in French zoos, and compared it with wild African savanna elephants. Fecal samples were collected and processed for DNA extraction and amplicon sequencing of the 16S rRNA gene.

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Background: Ticks can transmit a broad variety of pathogens of medical importance, including Borrelia afzelii, the causative agent of Lyme borreliosis in Europe. Tick microbiota is an important factor modulating, not only vector physiology, but also the vector competence. Anti-microbiota vaccines targeting keystone taxa of tick microbiota can alter tick feeding and modulate the taxonomic and functional profiles of bacterial communities in the vector.

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Most tick-borne pathogens (TBPs) are secondarily acquired by ticks during feeding on infected hosts, which imposes 'priority effect' constraints, as arrival order influences the establishment of new species in a microbial community. Here we tested whether once acquired, TBPs contribute to bacterial microbiota functioning by increasing community stability. For this, we used Hyalomma marginatum and Rhipicephalus bursa ticks collected from cattle in different locations of Corsica and combined 16S rRNA amplicon sequencing and co-occurrence network analysis, with high-throughput pathogen detection, and in silico removal of nodes to test for impact of rickettsial pathogens on network properties.

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The spread of the parasite Varroa destructor and associated viruses has resulted in massive honey bee colony losses with considerable economic and ecological impact. The gut microbiota has a major role in shaping honey bees tolerance and resistance to parasite infestation and viral infection, but the contribution of viruses to the assembly of the host microbiota in the context of varroa resistance and susceptibility remains unclear. Here, we used a network approach including viral and bacterial nodes to characterize the impact of five viruses, Apis Rhabdovirus-1 (ARV-1), Black Queen Cell virus (BQCV), Lake Sinai virus (LSV), Sacbrood virus (SBV) and Deformed wing virus (DWV) on the gut microbiota assembly of varroa-susceptible and Gotland varroa-surviving honey bees.

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Article Synopsis
  • * The researchers found that bleach washes significantly altered the microbiota composition in female ticks, indicating that bleach may penetrate and disrupt the internal microbiota.
  • * The ovary is identified as a crucial source of the tick microbiota, while the roles of other reproductive structures in microbiota contribution remain unclear, highlighting the need for further research on effective decontamination protocols.
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