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Positive coping styles and perigenual ACC volume: two related mechanisms for conferring resilience?
(2016)Social Cognitive and Affective NeuroscienceStress exposure has been linked to increased rates of depression and anxiety in adults, particularly in females, and has been associated with maladaptive changes in the anterior cingulate cortex (ACC), which is an important brain structure involved in internalizing disorders. Coping styles are important mediators of the stress reaction by establishing homeostasis, and may thus confer resilience to stress-related psychopathology. Anatomical ...Journal Article -
Adaptation to parasites and costs of parasite resistance in mutator and non-mutator bacteria
(2016)Molecular Biology and EvolutionParasitism creates selection for resistance mechanisms in host populations and is hypothesized to promote increased host evolvability. However, the influence of these traits on host evolution when parasites are no longer present is unclear. We used experimental evolution and whole-genome sequencing of Escherichia coli to determine the effects of past and present exposure to parasitic viruses (phages) on the spread of mutator alleles, ...Journal Article -
Dorsal anterior cingulate lactate and glutathione levels in euthymic bipolar i disorder: 1H-MRS study
(2016)The International Journal of NeuropsychopharmacologyObjective: Oxidative stress and mitochondrial dysfunction are 2 closely integrated processes implicated in the physiopathology of bipolar disorder. Advanced proton magnetic resonance spectroscopy techniques enable the measurement of levels of lactate, the main marker of mitochondrial dysfunction, and glutathione, the predominant brain antioxidant. The objective of this study was to measure brain lactate and glutathione levels in bipolar ...Journal Article -
Phylodynamics with Migration: A Computational Framework to Quantify Population Structure from Genomic Data
(2016)Molecular Biology and EvolutionWhen viruses spread, outbreaks can be spawned in previously unaffected regions. Depending on the time and mode of introduction, each regional outbreak can have its own epidemic dynamics. The migration and phylodynamic processes are often intertwined and need to be taken into account when analyzing temporally and spatially structured virus data. In this article, we present a fully probabilistic approach for the joint reconstruction of ...Journal Article -
First-Step Mutations during Adaptation Restore the Expression of Hundreds of Genes
(2016)Molecular Biology and EvolutionThe temporal change of phenotypes during the adaptive process remains largely unexplored, as do the genetic changes that affect these phenotypic changes. Here we focused on three mutations that rose to high frequency in the early stages of adaptation within 12 Escherichia coli populations subjected to thermal stress (42 °C). All the mutations were in the rpoB gene, which encodes the RNA polymerase beta subunit. For each mutation, we ...Journal Article -
Quantifying Age-dependent Extinction from Species Phylogenies
(2016)Systematic BiologySeveral ecological factors that could play into species extinction are expected to correlate with species age, i.e., time elapsed since the species arose by speciation. To date, however, statistical tools to incorporate species age into likelihood-based phylogenetic inference have been lacking. We present here a computational framework to quantify age-dependent extinction through maximum likelihood parameter estimation based on phylogenetic ...Journal Article -
Programmable colloidal molecules from sequential capillarity-assisted particle assembly
(2016)Science AdvancesThe assembly of artificial nanostructured and microstructured materials which display structures and functionalities that mimic nature’s complexity requires building blocks with specific and directional interactions, analogous to those displayed at the molecular level. Despite remarkable progress in synthesizing “patchy” particles encoding anisotropic interactions, most current methods are restricted to integrating up to two compositional ...Journal Article -
An anticancer drug suppresses the primary nucleation reaction that initiates the production of the toxic Ab42 aggregates linked with Alzheimer’s disease
(2016)Science AdvancesThe conversion of the β-amyloid (Aβ) peptide into pathogenic aggregates is linked to the onset and progression of Alzheimer’s disease. Although this observation has prompted an extensive search for therapeutic agents to modulate the concentration of Aβ or inhibit its aggregation, all clinical trials with these objectives have so far failed, at least in part because of a lack of understanding of the molecular mechanisms underlying the ...Journal Article -
Domain morphology, boundaries, and topological defects in biophotonic gyroid nanostructures of butterfly wing scales
(2016)Science AdvancesMany organisms in nature have evolved sophisticated cellular mechanisms to produce photonic nanostructures and, in recent years, diverse crystalline symmetries have been identified and related to macroscopic optical properties. However, because we know little about the distributions of domain sizes, the orientations of photonic crystals, and the nature of defects in these structures, we are unable to make the connection between the ...Journal Article -
Complementary-addressed site-directed spin labeling of long natural RNAs
(2016)Nucleic Acids ResearchNanoscale distance measurements by pulse dipolar Electron paramagnetic resonance (EPR) spectroscopy allow new insights into the structure and dynamics of complex biopolymers. EPR detection requires site directed spin labeling (SDSL) of biomolecule(s), which remained challenging for long RNAs up-to-date. Here, we demonstrate that novel complementary-addressed SDSL approach allows efficient spin labeling and following structural EPR studies ...Journal Article