Daytime DNase-I Administration Protects Mice From Ischemic Stroke Without Inducing Bleeding or tPA-Induced Hemorrhagic Transformation, Even With Aspirin Pretreatment.

Background: Acute ischemic stroke treatment typically involves tissue-type plasminogen activator (tPA) or tenecteplase, but about 50% of patients do not achieve successful reperfusion. The causes of tPA resistance, influenced by thrombus composition and timing, are not fully clear. Neutrophil extracellular traps (NETs), associated with poor outcomes and reperfusion resistance, contribute to thrombosis.

The iMab antibody selectively binds to intramolecular and intermolecular i-motif structures.

i-Motifs (iMs) are quadruplex nucleic acid conformations that form in cytosine-rich regions. Because of their acidic pH dependence, iMs were thought to form only in vitro. The recent development of an iM-selective antibody, iMab, has allowed iM detection in cells, which revealed their presence at gene promoters and their cell cycle dependence.

Human genomic DNA is widely interspersed with i-motif structures.

DNA i-motif structures are formed in the nuclei of human cells and are believed to provide critical genomic regulation. While the existence, abundance, and distribution of i-motif structures in human cells has been demonstrated and studied by immunofluorescent staining, and more recently NMR and CUT&Tag, the abundance and distribution of such structures in human genomic DNA have remained unclear. Here we utilise high-affinity i-motif immunoprecipitation followed by sequencing to map i-motifs in the purified genomic DNA of human MCF7, U2OS and HEK293T cells.

Characterization of an HNA aptamer suggests a non-canonical G-quadruplex motif.

Nucleic acids not only form the basis of heredity, but are increasingly a source of novel nano-structures, -devices and drugs. This has spurred the development of chemically modified alternatives (xeno nucleic acids (XNAs)) comprising chemical configurations not found in nature to extend their chemical and functional scope. XNAs can be evolved into ligands (XNA aptamers) that bind their targets with high affinity and specificity.