Publications by authors named "J R Portman"
Background: The MIMIX platform is a novel microneedle array patch (MAP) characterized by slowly dissolving microneedle tips that deploy into the dermis following patch application. We describe safety, reactogenicity, tolerability and immunogenicity for MIMIX MAP vaccination against influenza.
Methodology: The trial was a Phase 1, exploratory, first-in-human, parallel randomized, rater, participant, study analyst-blinded, placebo-controlled study in Canada.
The liver has a unique ability to regenerate; however, in the setting of acute liver failure (ALF), this regenerative capacity is often overwhelmed, leaving emergency liver transplantation as the only curative option. Here, to advance understanding of human liver regeneration, we use paired single-nucleus RNA sequencing combined with spatial profiling of healthy and ALF explant human livers to generate a single-cell, pan-lineage atlas of human liver regeneration. We uncover a novel ANXA2 migratory hepatocyte subpopulation, which emerges during human liver regeneration, and a corollary subpopulation in a mouse model of acetaminophen (APAP)-induced liver regeneration.
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- DNA experiences high mechanical stress from bending and twisting in various biological structures, such as nucleosomes and virus capsids, affecting essential processes like packaging and gene regulation.
- A new ligation assay developed on nicked DNA circles shows that DNA can unwind to over 11 base pairs per turn when curving tightly, challenging the conventional belief that its helical structure remains consistent.
- This research necessitates a re-evaluation of DNA's mechanical model and its implications for molecular processes involving tightly bent DNA.
Recently, a large family of at least 14 discotic liquid crystals was discovered that are exceptions to the conventional paradigm that discotic mesogens tend to feature long, flexible tails on their periphery. To understand why these materials are liquid crystals, as well as the structural determinants of discotic phase behavior, we studied a group of closely related small tail-free disk-like molecules, including both mesogenic and non-mesogenic compounds differing only in the position of a single fluorine substituent. The rigidity and structural simplicity of these molecules make them well suited to for study by large, fully all-atom simulations.
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- We conducted experiments and computational modeling to investigate the accessibility of human telomeric overhangs made up of 4-28 repeats of the GGGTTA sequence, focusing on their ability to form G-quadruplex structures.
- Using the FRET-PAINT method, we probed how accessible these overhangs are to a short strand that binds to complementary G-Tracts, finding that the accessibility patterns vary based on the length of the overhangs.
- Our results indicate that overhangs with a multiple of four (4n) G-Tracts show broader accessibility, while those with a two extra repeats (4n+2) have narrower accessibility, suggesting that stability varies and the junction between single- and double-stranded