The interpretation of lung ultrasound is the result of the analysis of artifacts rather than exact representations of anatomical structures, which appear when changes in the physical properties of the lung occur. Its application to the study of interstitial lung disease (ILD) associated with autoimmune diseases has aroused great interest in the last 10 years, as evidenced by a growing number of publications studying its usefulness in the diagnostic process, as a prognostic marker and as an aid in monitoring of patients. The main elements in lung ultrasound interpretation in ILD are the B lines and the changes in the pleural line.
View Article and Find Full Text PDFThe most widely used method for intracellular RNA fluorescence labeling is MS2 labeling, which generally relies on the use of multiple protein labels targeted to multiple RNA (MS2) hairpin structures installed on the RNA of interest (ROI). While effective and conveniently applied in cell biology labs, the protein labels add significant mass to the bound RNA, which potentially impacts steric accessibility and native RNA biology. We have previously demonstrated that internal, genetically encoded, uridine-rich internal loops (URILs) comprised of four contiguous UU pairs (8 nt) in RNA may be targeted with minimal structural perturbation by triplex hybridization with 1 kD bifacial peptide nucleic acids (bPNAs).
View Article and Find Full Text PDFPurpose: Current speech-language pathology (SLP) services in Cambodia are limited in scope, service accessibility and integration into government systems. However, momentum is growing to develop an internationally recognised profession. This paper examines the depth and breadth of SLP support available to people with communication and/or swallowing difficulties in relation the Sustainable Development Goals (SDGs).
View Article and Find Full Text PDFDennis Bong, Philip Holliger, and Chaoyong Yang introduce the themed collection on XNA xeno-nucleic acids.
View Article and Find Full Text PDFThe interpretation of lung ultrasound (US) is the result of the analysis of artifacts, rather than exact representations of anatomical structures, which appear when changes in the physical properties of the lung occur. Its application to the study of interstitial lung disease (ILD) associated with autoimmune diseases has aroused great interest in the last 10 years, as evidenced by a growing number of publications studying its usefulness in the diagnostic process, as a prognostic marker, and as an aid in monitoring of patients. The main elements in lung US interpretation in ILD are the B lines and the changes in the pleural line.
View Article and Find Full Text PDFWe report a synthesis of bifacial peptide nucleic acids (bPNAs) with novel diketopiperazine (DKP) backbones that display unnatural melamine (M) bases, as well as native bases. To examine the structure-function scope of DKP bPNAs, we synthesized a set of bPNAs by using diaminopropionic acid, diaminobutyric acid, ornithine, and lysine derivatives to display the base-tripling motifs, which result in one, two, three, or four carbons linking the alpha carbon to the side-chain amine. Thermal denaturation of DNA hybrids with these bPNAs revealed that the optimal side-chain linkage was four carbons, corresponding to the lysine derivative.
View Article and Find Full Text PDFWe report herein a study on the impact of bifacial peptide nucleic acid (bPNA) amino acid composition and backbone modification on DNA binding. A series of bPNA backbone variants with identical net charge were synthesized to display either 4 or 6 melamine (M) bases. These bases form thymine-melamine-thymine (TMT) base-triples, resulting in triplex hybrid stem structures with T-rich DNAs.
View Article and Find Full Text PDFGeneral design principles for recognition at noncanonical interfaces of DNA and RNA remain elusive. Triplex hybridization of bifacial peptide nucleic acids (bPNAs) with oligo-T/U DNAs and RNAs is a robust recognition platform that can be used to define structure-function relationships in synthetic triplex formation. To this end, a set of minimal ( < 1 kD) bPNA variants was synthesized to probe the impact of amino acid secondary structural propensity, stereochemistry, and backbone cyclization on hybridization with short, unstructured T-rich DNA and U-rich RNAs.
View Article and Find Full Text PDFThe second part of the Guidelines and Recommendations for Musculoskeletal Ultrasound (MSUS), produced under the auspices of EFSUMB, following the same methodology as for Part 1, provides information and recommendations on the use of this imaging modality for joint pathology, pediatric applications, and musculoskeletal ultrasound-guided procedures. Clinical application, practical points, limitations, and artifacts are described and discussed for every joint or procedure. The document is intended to guide clinical users in their daily practice.
View Article and Find Full Text PDFWe hypothesize that programmable hybridization to noncanonical nucleic acid motifs may be achieved by macromolecular display of binders to individual noncanonical pairs (NCPs). As each recognition element may individually have weak binding to an NCP, we developed a semi-rational approach to detect low affinity interactions between selected nitrogenous bases and noncanonical sites in duplex DNA and RNA. A set of fluorogenic probes was synthesized by coupling abiotic (triazines, pyrimidines) and native RNA bases to thiazole orange (TO) dye.
View Article and Find Full Text PDFThe first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process.
View Article and Find Full Text PDFWe report herein a new class of synthetic reagents for targeting the element for nuclear expression (ENE) in MALAT1, a long noncoding RNA upregulated in many cancers. The -acting ENE contains a U-rich internal loop (URIL) that forms an 11 base UAU-rich triplex stem with the truncated 3' oligo-A tail of MALAT1, protecting the terminus from exonuclease digestion and greatly extending transcript lifetime. Bifacial peptide nucleic acids (bPNAs) similarly bind URILs base triple formation between two uracil bases and a synthetic base, melamine.
View Article and Find Full Text PDFInterstitial lung disease (ILD) is one of the most relevant extra-articular manifestations of rheumatic diseases resulting in a substantial increase in morbidity and mortality. Early diagnosis and close monitoring to identify patients at high risk of progression are crucial to establish the need for targeted treatment with immunomodulatory and antifibrotic drugs, with potential ability to change the course of the disease. However, there are unmet needs in this field as pulmonary auscultation, chest radiography, or pulmonary function studies do not allow identification of the most incipient stages of the disease.
View Article and Find Full Text PDFDengue virus infection depends on its fusion with the host membrane, where the binding occurs through interaction between proteins on the virus cell surface and specific viral receptors on target membranes. This process is mediated by the fusion peptide located between residues 98 and 112 (DRGWGNGCGLFGKGG) that forms a loop in domain II of dengue E glycoprotein. In this study, we evaluated the role of fusion peptide surrounding regions (88-97 and 113-123) of the Dengue 2 subtype on its interaction with the membrane and fusion activity.
View Article and Find Full Text PDFMorphine is a commonly used opioid drug to treat acute pain by binding to the mu-opioid receptor (MOR), but its effective analgesic efficacy via triggering of the heterotrimeric G protein pathway is accompanied by a series of adverse side effects via triggering of the β-arrestin pathway. Recently, PZM21, a recently developed MOR biased agonist, shows preferentially activating the G protein pathway over β-arrestin pathway. However, there is no high-resolution receptor structure in complex with PZM21 and its action mechanism remains elusive.
View Article and Find Full Text PDFThe notion of using synthetic heterocycles instead of the native bases to interface with DNA and RNA has been explored for nearly 60 years. Unnatural bases compatible with the DNA/RNA coding interface have the potential to expand the genetic code and co-opt the machinery of biology to access new macromolecular function; accordingly, this body of research is core to synthetic biology. While much of the literature on artificial bases focuses on code expansion, there is a significant and growing effort on docking synthetic heterocycles to noncoding nucleic acid interfaces; this approach seeks to illuminate major processes of nucleic acids, including regulation of transcription, translation, transport, and transcript lifetimes.
View Article and Find Full Text PDFHerein, we demonstrate context-dependent molecular recognition of DNA by synthetic bPNA iron and copper complexes, using oxidative backbone cleavage as a chemical readout for binding. Oligoethylenimine bPNAs displaying iron·EDTA or copper·phenanthroline sites were found to be efficient chemical nucleases for designed and native structured DNAs with T-rich single-stranded domains. Cleavage reactivity depends strongly on structural context, as strikingly demonstrated with DNA substrates of the form (GGGTTA).
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