Publications by authors named "Christophe Audebert"

sp. is the most common single-celled eukaryote colonizing the human gastrointestinal tract worldwide. Because of the proven zoonotic potential of this protozoan, sustained research is therefore focused on identifying various reservoirs of transmission to humans, and in particular animal sources.

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apicomplexan protozoa are ubiquitous intracellular agents affecting humans and animals. In particular, bovine cryptosporidiosis is recognized as endemic worldwide. However, epidemiological investigations remain limited in France regarding the burden of these parasites in cattle.

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The basis of any animal experimentation begins with the housing of animals that should take into account the need for splitting animals into similar groups. Even if it is generally recommended to use the minimum number of animals necessary to obtain reliable and statistically significant results (3Rs rule), the allocation of animals is currently mostly based on randomness. Since variability in gut microbiota is an important confounding factor in animal experiments, the main objective of this study was to develop a new approach based on 16S rRNA gene sequencing analysis of the gut microbiota of animals participating in an experiment, in order to correctly assign the animals across batches.

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In the fight against SARS-COV-2, the development of serological assays based on different antigenic domains represent a versatile tool to get a comprehensive picture of the immune response or differentiate infection from vaccination beyond simple diagnosis. Here we use a combination of the Nucleoprotein (NP), the Spike 1 (S1) and Spike 2 (S2) subunits, and the receptor binding domain (RBD) and N-terminal domain (NTD) of the Spike antigens from the CoViDiag® multiplex IgG assay, to follow the immune response to SARS-CoV-2 infection over a long time period and depending on disease severity. Using a panel of 209 sera collected from 61 patients up to eight months after infection, we observed that most patients develop an immune response against multiple viral epitope, but anti-S2 antibodies seemed to last longer.

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Human gut microbial communities are mainly composed of bacteria, but also include fungi, viruses, archaea, and protozoa, whose role in the gut ecosystem has only recently begun to be recognized. For example, humans colonized by (a gut protozoan with controversial pathogenicity) host a more diverse bacterial microbiota than individuals not carrying it, suggesting that its presence may be beneficial for the host. In parallel, the presence of non-pathogenic spp.

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Article Synopsis
  • Three porcine enteric coronaviruses—PEDV, TGEV, and PDCoV—are affecting U.S. swine herds, requiring effective lab methods for diagnosis.
  • This study created a multiplex immunoassay using virus-specific proteins to simultaneously detect these viruses in one sample, similar to standard ELISA techniques.
  • The test showed high diagnostic sensitivity, achieving 92% for PEDV, 100% for TGEV, and 98% for PDCoV, confirming it as a reliable tool for diagnosing these infections in pigs.
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Cryptosporidium parvum is known to cause life-threatening diarrhea in immunocompromised hosts and was also reported to be capable of inducing digestive adenocarcinoma in a rodent model. Interestingly, three carcinogenic isolates of C. parvum, called DID, TUM1 and CHR, obtained from fecal samples of naturally infected animals or humans, showed higher virulence than the commercially available C.

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Targeted metagenomics is the solution of choice to reveal differential microbial profiles (defined by richness, diversity and composition) as part of case-control studies. It is well documented that each data processing step may have the potential to introduce bias in the results. However, selecting a bioinformatics pipeline to analyze high-throughput sequencing data from A to Z remains one of the critical considerations in a case-control microbiota study design.

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Article Synopsis
  • Gut commensal bacteria play a crucial role in maintaining immune balance, and changes in their composition are linked to diseases like autoimmunity and inflammation.
  • Researchers studied the gut microbiota of GalT-KO mice over 7 months using advanced sequencing methods, focusing on the diversity of specific bacterial types and their correlation with natural anti-glycan antibodies.
  • Findings suggest that specific bacterial orders are linked to the development of these antibodies, with changes in microbiota diversity impacting antibody levels and types, although not all diversity changes affect the gut microbiome's overall function.
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High throughput sequencing has opened up new clinical opportunities moving towards a medicine of precision. Oncology, infectious diseases or human genomics, many applications have been developed in recent years. The introduction of a third generation of nanopore-based sequencing technology, addressing some of the weaknesses of the previous generation, heralds a new revolution.

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The increase in available sequence data has advanced the field of microbiology; however, making sense of these data without bioinformatics skills is still problematic. We describe MICRA, an automatic pipeline, available as a web interface, for microbial identification and characterization through reads analysis. MICRA uses iterative mapping against reference genomes to identify genes and variations.

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In the past decade, metagenomics studies have become widespread due to the arrival of second-generation sequencing platforms characterized by low costs, high throughput and short read lengths. Today, although benchtop sequencers are considered to be accurate platforms to deliver data for targeted metagenomics studies, the limiting factor has become the analysis of these data. In a previous paper, we performed an Ion Torrent PGM 16S rDNA gene sequencing of faecal DNAs from 48 Blastocystis-colonized patients and 48 Blastocystis-negative subjects, in order to decipher the impact of this widespread protist on gut microbiota composition and diversity.

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Targeted metagenomics, also known as metagenetics, is a high-throughput sequencing application focusing on a nucleotide target in a microbiome to describe its taxonomic content. A wide range of bioinformatics pipelines are available to analyze sequencing outputs, and the choice of an appropriate tool is crucial and not trivial. No standard evaluation method exists for estimating the accuracy of a pipeline for targeted metagenomics analyses.

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Introduction And Purpose: Propidium monoazide (PMA)-pretreatment has increasingly been applied to remove the bias from dead or damaged cell artefacts, which could impact the microbiota analysis by high-throughput sequencing. Our study aimed to determine whether a PMA-pretreatment coupled with high-throughput sequencing analysis provides a different picture of the airway mycobiome and bacteriome.

Results And Discussion: We compared deep-sequencing data of mycobiota and microbiota of 15 sputum samples from 5 cystic fibrosis (CF) patients with and without prior PMA-treatment of the DNA-extracts.

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Alterations in the composition of commensal bacterial populations, a phenomenon known as dysbiosis, are linked to multiple gastrointestinal disorders, such as inflammatory bowel disease and irritable bowel syndrome, or to infections by diverse enteric pathogens. Blastocystis is one of the most common single-celled eukaryotes detected in human faecal samples. However, the clinical significance of this widespread colonization remains unclear, and its pathogenic potential is controversial.

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To quantitatively assess the risk of contamination by Pneumocystis depending on the degree of immunosuppression (ID) of the exposed rat hosts, we developed an animal model, where rats went through different doses of dexamethasone. Then, natural and aerial transmission of Pneumocystis carinii occurred during cohousing of the rats undergoing gradual ID levels (receivers) with nude rats developing pneumocystosis (seeders). Following contact between receiver and seeder rats, the P.

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Background: Inflammatory bowel diseases are incurable illnesses of the gastrointestinal tract, which substantially enhance the risk of developing colorectal carcinogenesis. Conventional photodynamic therapy is a clinically approved therapeutic modality used in the treatment of neoplastic diseases. Recent preclinical and clinical studies have shown that photodynamic therapy with low doses of photosensitizer and/or light improves inflammatory conditions, including colitis.

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During a pathogen outbreak, the emergency resides in the identification and characterization of the infectious agent. In addition to the traditional phenotypic methods which are still widely used, the molecular biology is nowadays a common approach of clinical microbiology labs and the pathogen can be identified by comparing its molecular fingerprint to a data-bank. High-throughput sequencing should allow overcoming this single identification to exploit the whole information encoded in the pathogen genome.

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The recent progresses of high-throughput sequencing (HTS) technologies enable easy and cost-reduced access to whole genome sequencing (WGS) or re-sequencing. HTS associated with adapted, automatic and fast bioinformatics solutions for sequencing applications promises an accurate and timely identification and characterization of pathogenic agents. Many studies have demonstrated that data obtained from HTS analysis have allowed genome-based diagnosis, which has been consistent with phenotypic observations.

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In order to standardize a polymerase chain reaction (PCR)-based method of Pneumocystis detection, we describe the development of an improved PCR method that targets the Pneumocystis mtLSUrRNA gene. Design of a new primer pair and PCR program with suitable parameters and optimization resulted in a simpler and faster single-round amplification assay. The sensitivity of the novel Pneumocystis genus-specific PCR proved comparable to the reference nested PCR.

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Background: The rapid evolution in high-throughput sequencing (HTS) technologies has opened up new perspectives in several research fields and led to the production of large volumes of sequence data. A fundamental step in HTS data analysis is the mapping of reads onto reference sequences. Choosing a suitable mapper for a given technology and a given application is a subtle task because of the difficulty of evaluating mapping algorithms.

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Cryptosporidium species are apicomplexan protozoans that are found worldwide. These parasites constitute a large risk to human and animal health. They cause self-limited diarrhea in immunocompetent hosts and a life-threatening disease in immunocompromised hosts.

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