Publications by authors named "Dubourg G"

Objectives: In this review, we provide an overview of the composition of the microbiota associated with these two dental pathologies, caries and tartar, highlighting the microbial profiles associated with each pathology.

Design: This literature review was carried out by a manual search of two electronic databases, PubMed and Web of Science (WOS), using specific keywords to the two oral pathologies dental caries and calculus.

Results: The oral microbial community is known for its complexity, and comprises hundreds of species of different micro-organisms.

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The application of metal oxide nanomaterials (MO NMs) in the agrifood industry offers innovative solutions that can facilitate a paradigm shift in a sector that is currently facing challenges in meeting the growing requirements for food production, while safeguarding the environment from the impacts of current agriculture practices. This review comprehensively illustrates recent advancements and applications of MO for sustainable practices in the food and agricultural industries and environmental preservation. Relevant published data point out that MO NMs can be tailored for specific properties, enabling advanced design concepts with improved features for various applications in the agrifood industry.

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The emergence of the coronavirus pandemic facilitated the acquisition of mutations in the SARS-CoV-2 genome, resulting in the appearance of new variants over the past three years. We previously identified several taxa associated with the clinical outcome of COVID-19 disease in a retrospective study involving 120 patients (infected patients and negative subjects). However, little is known about whether the different variants could influence variations in the composition of the nasopharyngeal microbiota.

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Article Synopsis
  • Respiratory infections, primarily caused by viruses, are a major health issue globally, and a study was conducted in rural Senegal to investigate the presence of viruses and bacteria in symptomatic and asymptomatic individuals.
  • The research found that 83.6% of symptomatic individuals tested positive for at least one respiratory virus, with influenza A, metapneumovirus, and enterovirus being notably more common among those with symptoms, while 21.8% of asymptomatic individuals also had viral infections.
  • Additionally, 82.0% of symptomatic subjects carried at least one respiratory bacterium, with Moraxella catarrhalis and Streptococcus pneumoniae being the most common, highlighting the need for further surveillance of these pathogens
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The cause of death of Saint-Louis is not known, but recent findings indicated that he presented scurvy and inflammatory jaw disease, which has been associated with infection by oral commensals. Here, we have the exceptional opportunity to analyze the relics of the viscera of King Saint-Louis. A 4.

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Blood is a precious biological liquid that is normally sterile. Therefore, bacteria in the bloodstream are shown a priori anomaly. A blood culture is systematically performed to diagnose the cause of the bacteremia.

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Formyl peptide receptor-1 (FPR1) is a pattern recognition receptor that is mostly expressed by myeloid cells. In patients with colorectal cancer (CRC), a loss-of-function polymorphism (rs867228) in the gene coding for FPR1 has been associated with reduced responses to chemotherapy or chemoradiotherapy. Moreover, rs867228 is associated with accelerated esophageal and colorectal carcinogenesis.

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Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) are powerful tools to study the ultrastructure of numerous specimens and to determine their elemental composition, respectively. However, results have not yet been reported on their application to urine samples in routine clinical laboratory practice. Herein we investigate urine sediment by using SEM and EDX to detect and identify different urine components.

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Episodes of bacterial superinfections have been well identified for several respiratory viruses, notably influenza. In this retrospective study, we compared the frequency of superinfections in COVID-19 patients to those found in influenza-positive patients, and to controls without viral infection. We included 42 468 patients who had been diagnosed with COVID-19 and 266 261 subjects who had tested COVID-19 negative between 26 February 2020 and 1 May 2021.

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Strain Marseille-P4119T was isolated from a faecal sample of a healthy 32-year-old faecal transplant donor. The bacterium was anaerobic, Gram-negative, rod-shaped, non-motile, and did not produce spores. We studied its phenotypic characteristics and sequenced its whole genome.

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Strain Marseille-P8396 is a new species isolated from a patient with recurrent Clostridioides difficile infection. Its optimal growth condition was observed at pH of 7.5, at a temperature of 37 °C after 72 h of incubation on Columbia agar (BioMérieux, France) with 5% sheep blood, under an anaerobic atmosphere.

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While populations at risk for severe SARS-CoV-2 infections have been clearly identified, susceptibility to the infection and its clinical course remain unpredictable. As the nasopharyngeal microbiota may promote the acquisition of several respiratory infections and have an impact on the evolution of their outcome, we studied the nasopharyngeal microbiota of COVID-19 patients in association with baseline disease-related clinical features compared to that of patients tested negative. We retrospectively analyzed 120 nasopharyngeal pseudonymized samples, obtained for diagnosis, divided into groups (infected patients with a favorable outcome, asymptomatic, and deceased patients) and patients tested negative for SARS-CoV-2, by using Illumina-16S ribosomal ribonucleic acid (rRNA) sequencing and specific polymerase chain reaction (PCR) targeting pathogens.

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Blood cultures detected as positive by the automated system but negative by microscopy and subculture are considered as "false-positives." Several causes have been identified, including hyperleukocytosis or the presence of fastidious bacteria, but as many cases remain unexplained we aimed to investigate the false positives occurring in our laboratory. We retrospectively collected data on blood cultures received over a period of 12 months to determine factors associated with the false-positive vials.

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Article Synopsis
  • Blood is typically sterile tissue, but in this study, three bacterial strains were isolated from individuals suffering from bacteremia for further investigation.* -
  • The strains included two Gram-positive non-spore-forming rod-shaped bacteria (Marseille-P7157T and Marseille-Q2854T) and one Gram-negative motile rod-shaped bacterium (Marseille-P8049T), with distinct major fatty acids identified.* -
  • Genomic analysis revealed significant sequence similarities with known species, leading to the classification of these newly isolated strains as different species: Acinetobacter ihumii sp. nov., Microbacterium ihumii sp. nov., and Gulosibacter massiliensis sp. nov.*
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The higher incidence of bladder cancer in men has long been attributed to environmental factors, including smoking. The fact that the sex ratio of bladder cancer remains consistently weighted toward men despite the remarkable increase in the prevalence of smoking among women suggests that other risk factors influence the incidence rates of bladder cancer. These factors may include the urinary microbiota.

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Background: We aimed to compare the clinical severity in patients who were coinfected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and rhinovirus or monoinfected with a single one of these viruses.

Methods: The study period ranged from 1 March 2020 to 28 February 2021 (one year). SARS-CoV-2 and other respiratory viruses were identified by real-time reverse-transcription-PCR as part of the routine work at Marseille University hospitals.

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From 2015 to 2017, 3197 interpretable Bordetella polymerase chain reaction (PCR) tests were performed for 2760 children presenting to our tertiary university hospital. Requests mainly came from the emergency department (62%) and for children older than 1 year (68%). Only 32 PCR (1%) results were positive, mainly in children younger than 1 year (n = 29/32, 90.

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We report here the complete genome sequences of three Bacillus cereus group strains isolated from blood cultures from premature and immunocompromised infants hospitalized in intensive care units in three French hospitals. These complete genome sequences were obtained from a combination of Illumina HiSeq X Ten short reads and Oxford Nanopore MinION long reads.

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Thanks to its ability to isolate previously uncultured bacterial species, culturomics has dynamized the study of the human microbiota. A new bacterial species, Gemella massiliensis Marseille-P3249, was isolated from a sputum sample of a healthy French man. Strain Marseille-P3249 is a facultative anaerobe, catalase-negative, Gram positive, coccus, and unable to sporulate.

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Antibiotic resistance genes exist naturally in various environments far from human usage. Here, we investigated multidrug-resistant Klebsiella pneumoniae, a common pathogen of chimpanzees and humans. We screened antibiotic-resistant K.

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