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At birth, mammals experience a massive colonization by microorganisms. We previously reported that newborn mice gestated and born germ-free (GF) have increased microglial labeling and alterations in developmental neuronal cell death in the hippocampus and hypothalamus, as well as greater forebrain volume and body weight when compared to conventionally colonized (CC) mice. To test whether these effects are solely due to differences in postnatal microbial exposure, or instead may be programmedin utero, we cross-fostered GF newborns immediately after birth to CC dams (GF→CC) and compared them to offspring fostered within the same microbiota status (CC→CC, GF→GF). Because key developmental events (including microglial colonization and neuronal cell death) shape the brain during the first postnatal week, we collected brains on postnatal day (P) 7. To track gut bacterial colonization, colonic content was also collected and subjected to 16S rRNA qPCR and Illumina sequencing. In the brains of GF→GF mice, we replicated most of the effects seen previously in GF mice. Interestingly, the GF brain phenotype persisted in GF→CC offspring for almost all measures. In contrast, total bacterial load did not differ between the CC→CC and GF→CC groups on P7, and bacterial community composition was also very similar, with a few exceptions. Thus, GF→CC offspring had altered brain development during at least the first 7 days after birth despite a largely normal microbiota. This suggests that prenatal influences of gestating in an altered microbial environment programs neonatal brain development.
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Reductive defluorination of graphite monofluoride by weak, non-nucleophilic reductants reveals low-lying electron-accepting sites
Graphite monofluoride (GF) can undergo reductive defluorination in the presence of weak, non-nucleophilic reductants. This leads to a new approach to GF–polyaniline composites as cathode materials for significantly improving the discharge capacity of primary lithium batteries. We postulate that the reduction is mediated by residual π-bonds in GF.
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- Award ID(s):
- 1665427
- PAR ID:
- 10059421
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 20
- Issue:
- 21
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 14287 to 14290
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8cp00384j
