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Maillard, A.

Publications and source records attributed to Maillard, A..

3 recordsLinked to original sources

Rare CNVs and phenome-wide profiling: a tale of brain-structural divergence and phenotypical convergence

Copy number variations (CNVs) are rare genomic deletions and duplications that can exert profound effects on brain and behavior. Previous reports of pleiotropy in CNVs imply that they converge on shared mechanisms at some level of pathway cascades, from genes to large-scale neural circuits to the phenome. However, studies to date have primarily examined single CNV loci in small clinical cohorts. It remains unknown how distinct CNVs escalate the risk for the same developmental and psychiatric disorders. Here, we quantitatively dissect the impact on brain organization and behavioral differentiation across eight key CNVs. In 534 clinical CNV carriers from multiple sites, we explored CNV-specific brain morphology patterns. We extensively annotated these CNV-associated patterns with deep phenotyping assays through the UK Biobank resource. Although the eight CNVs cause disparate brain changes, they are tied to similar phenotypic profiles across [~]1000 lifestyle indicators. Our population-level investigation established brain structural divergences and phenotypical convergences of CNVs, with direct relevance to major brain disorders.

genetics↗

Performances of NeuMoDx, a random-access system for HBV-DNA and HCV-RNA quantification

Viral loads (VL) monitoring for hepatitis B and C is essential to evaluate disease progression and treatment response. Automated, random-access rapid systems are becoming standard to provide reliable VL to clinicians. The aim of this study was to evaluate the analytical performances of the recently launched NeuMoDx for HBV-DNA and HCV-RNA quantification. Clinical samples routinely quantified on the Beckman-Veris system were either retrospectively (frozen samples; HBV n=178, HCV n=249), or in parallel (fresh primary tubes; HBV n=103, HCV n=124) tested using NeuMoDx. Linearity range was assessed on serial dilutions of high tittered plasmas containing different genotypes for HBV (A-E, n=10) and HCV (1a-b, 2-5, n=12). Overall test failure, mostly internal control amplification failure, was 2.3% and was not influenced by matrix types. For HBV-VL, Kappa agreement was 74%, with 27 (12.6%) discrepancies. Correlation between HBV assays on 72 quantified samples by both methods was excellent (r=0.963) with a mean bias (NeuMoDx-Veris) of 0.21 log IU/mL. For HCV-VL, Kappa agreement reached 94%, with 9 (2.8%) discrepancies. The r-correlation factor between assays on 104 samples was 0.960 with a mean bias of -0.14 log IU/mL (NeuMoDx-Veris). Serial dilutions confirmed the claimed linear ranges for all HBV and HCV genotypes. The mean turnaround time was 72 [55-101] for HBV and 96 [78-133] for HCV. These results obtained on the NeuMoDx confirmed the overall good functionality of the system with a short turn-around-time, full traceability and easy handling. These results on HBV- and HCV-VL look promising and should be challenged with further comparisons.

microbiology↗

Short-term evolution under copper stress increases probability of plasmid uptake

Understanding plasmid transfer dynamics remains a key knowledge gap in the mitigation of antibiotic resistance gene spread. Direct effects of exposure to stressors on plasmid uptake are well monitored. However, it remains untested whether evolution of strains under stress conditions modulates subsequent plasmid uptake. Here, we evolved a compost derived microbial community for six weeks under copper stress and non-exposed control conditions. We then tested the ability of isolated clones from both treatments to take up the broad host range plasmid pKJK5 from an E.coli donor strain. Clones pre-adapted to copper displayed a significantly increased probability to be permissive towards the plasmid compared to those isolated from the control treatment. Further, increased phylogenetic distance to the donor strain was significantly and negatively correlated with plasmid uptake probabilities across both treatments.

microbiology↗