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Norwood, K.

Publications and source records attributed to Norwood, K..

3 recordsLinked to original sources

In silico genomic surveillance by CoVerage predicts and characterizes SARS-CoV-2 Variants of Interest

Rapidly evolving viral pathogens such as SARS-CoV-2 continuously accumulate amino acid changes, some of which affect transmissibility, virulence or improve the virus ability to escape host immunity. Since the beginning of the pandemic and establishment of SARS-CoV-2 as a human pathogen, multiple lineages with concerning phenotypic alterations, so called Variants of Concern (VOCs), have emerged and risen to predominance. To optimize public health management and to ensure the continued efficacy of vaccines, the early detection of such variants of interest is essential. Therefore, large-scale viral genomic surveillance programs have been initiated worldwide, with data being deposited in public repositories in a timely manner. However, technologies for their continuous interpretation are currently lacking. Here, we describe the CoVerage system (www.sarscoverage.org) for viral genomic surveillance, which continuously predicts and characterizes novel and emerging potential Variants of Interest (pVOIs) from country-wise lineage frequency dynamics together with their antigenic and evolutionary alterations utilizing the GISAID viral genome resource. In a comprehensive assessment of VOIs, VOCs and VUMs identified, we demonstrate how CoVerage can be used to swiftly identify and characterize such variants, with a lead time of almost three months relative to them reaching their maximal abundances. CoVerage can facilitate the timely identification and assessment of future SARS-CoV-2 variants relevant for public health.

bioinformatics↗

Multi-modal imaging of a single postmortem mouse brain over five orders of magnitude of resolution

Mammalian neurons operate at length scales spanning five orders of magnitude; micron-scale-diameter myelinated axons project millimeters across brain regions, ultimately forming nanometer scale synapses on individual post-synaptic neurons. Capturing these anatomical features across that breadth of scale has required imaging samples with multiple independent imaging modalities (e.g. MRI, electron microscopy, etc.). Translating between the different modalities, however, requires imaging the same brain with each. Here, we imaged the same postmortem mouse brain over five orders of spatial resolution using MRI, whole brain micron-scale synchrotron x-ray tomography (CT), and large volume automated serial electron microscopy. Using this pipeline, we can track individual myelinated axons previously relegated to axon bundles in diffusion tensor MRI or arbitrarily trace neurons and their processes brain-wide and identify individual synapses on them. This pipeline provides both an unprecedented look across a single brains multi-scaled organization as well as a vehicle for studying the brains multi-scale pathologies.

neuroscience↗

Defective intestinal repair after short-term high fat diet due to loss of efferocytosis

Defective tissue repair is a hallmark of many inflammatory disorders including, inflammatory bowel disease (IBD). While it is clear that high fat diets (HFD) can exacerbate inflammatory disease by increasing inflammation, the direct effect of lipids on tissue homeostasis and repair remains undefined. We show here that short term exposure to HFD directly impairs barrier repair after intestinal epithelial damage by interfering with recognition and uptake of apoptotic neutrophils by intestinal macrophages. Apoptotic neutrophil uptake induces macrophage IL-10 production, which is lacking after intestinal damage in the context of HFD. Overexpression of IL-10 rescues repair defects after HFD treatment, but not if epithelial cells lack the IL-10 receptor, highlighting the key role of IL-10 in barrier repair. These findings demonstrate a previously unidentified mechanism by which dietary lipids directly interfere with homeostatic processes required to maintain tissue integrity.

cell biology↗