SUPRAORBITAL AND ENDONASAL APPROACHES: TAILORING SURGICAL TECHNIQUES FOR TUBERCULUM SELLAE MENINGIOMAS BASED ON PREOPERATIVE GRADING SYSTEMS.

Background Tuberculum sellae meningiomas (TSM) tend to compress the optic apparatus and an ideal surgical route, whether transcranial or endonasal, is still debated. Another issue is if the minimally invasive supraorbital (SO) approach offers the same results compared to the more invasive craniotomy. Aiming to guide approach selection, preoperative grading systems have been described.

Silver(I)-Mediated 2D DNA Nanostructures.

Structural DNA nanotechnology enables the self-organization of matter at the nanometer scale, but approaches to expand the inorganic and electrical functionality of these scaffolds remain limited. Developments in nucleic acid metallics have enabled the incorporation of site-specific metal ions in DNA duplexes and provide a means of functionalizing the double helix with atomistic precision. Here a class of 2D DNA nanostructures that incorporate the cytosine-Ag-cytosine (dC:Ag:dC) base pair as a chemical trigger for self-assembly is described.

Six-Letter DNA Nanotechnology: Incorporation of - Base Pairs into Self-Assembling 3D Crystals.

Artificially expanded genetic information systems (AEGIS) were developed to expand the diversity and functionality of biological systems. Recent experiments have shown that these expanded DNA molecular systems are robust platforms for information storage and retrieval as well as useful for basic biotechnologies. In tandem, nucleic acid nanotechnology has seen the use of information-based "semantomorphic" encoding to drive the self-assembly of a vast array of supramolecular devices.

Engineering tertiary chirality in helical biopolymers.

Tertiary chirality describes the handedness of supramolecular assemblies and relies not only on the primary and secondary structures of the building blocks but also on topological driving forces that have been sparsely characterized. Helical biopolymers, especially DNA, have been extensively investigated as they possess intrinsic chirality that determines the optical, mechanical, and physical properties of the ensuing material. Here, we employ the DNA tensegrity triangle as a model system to locate the tipping points in chirality inversion at the tertiary level by X-ray diffraction.

Environmentally Controlled Oscillator with Triplex Guided Displacement of DNA Duplexes.

The use of DNA triplex association is advantageous for the reconfiguration of dynamic DNA nanostructures through pH alteration and can provide environmental control for both structural changes and molecular signaling. The combination of pH-induced triplex-forming oligonucleotide (TFOs) binding with toehold-mediated strand displacement has recently garnered significant attention in the field of structural DNA nanotechnology. While most previous studies use single-stranded DNA to displace or replace TFOs within the triplex, here we demonstrate that pH alteration allows a DNA duplex, with a toehold assistance, to displace TFOs from the components of another DNA duplex.