Search results for " G4"

Development of Polyamine‐Substituted Triphenylamine Ligands with High Affinity and Selectivity for G‐Quadruplex DNA

2019

Currently, significant efforts are devoted to designing small molecules able to bind selectively to guanine quadruplexes (G4s). These noncanonical DNA structures are implicated in various important biological processes and have been identified as potential targets for drug development. Previously, a series of triphenylamine (TPA)-based compounds, including macrocyclic polyamines, that displayed high affinity towards G4 DNA were reported. Following this initial work, herein a series of second-generation compounds, in which the central TPA has been functionalised with flexible and adaptive linear polyamines, are presented with the aim of maximising the selectivity towards G4 DNA. The acid-bas…

Ruthenium-arene complexes bearing naphthyl-substituted 1,3-dioxoindan-2-carboxamides ligands for G-quadruplex DNA recognition.

2019

Quadruplex nucleic acids – DNA/RNA secondary structures formed in guanine rich sequences – proved to have key roles in the biology of cancers and, as such, in recent years they emerged as promising targets for small molecules. Many reports demonstrated that metal complexes can effectively stabilize quadruplex structures, promoting telomerase inhibition, downregulation of the expression of cancer-related genes and ultimately cancer cell death. Although extensively explored as anticancer agents, studies on the ability of ruthenium arene complexes to interact with quadruplex nucleic acids are surprisingly almost unknown. Herein, we report on the synthesis and characterization of four novel Ru(…

Unveiling the spatial structure of the overionized plasma in the supernova remnant W49B

2011

W49B is a mixed-morphology supernova remnant with thermal X-ray emission dominated by the ejecta. In this remnant, the presence of overionized plasma has been directly established, with information about its spatial structure. However, the physical origin of the overionized plasma in W49B has not yet been understood. We investigate this intriguing issue through a 2D hydrodynamic model that takes into account, for the first time, the mixing of ejecta with the inhomogeneous circumstellar and interstellar medium, the thermal conduction, the radiative losses from optically thin plasma, and the deviations from equilibrium of ionization induced by plasma dynamics. The model was set up on the basi…

Immunoglobulin G4-Related Aortitis and Severe Aortic Valve Stenosis Treated With Transcatheter Aortic Valve Replacement and Immunosuppression.

2021

Abstract IgG4-related disease is an immune-mediated fibro-inflammatory disorder with multisystemic involvement. Aortitis and peri-aortitis are the most common cardiovascular manifestations of the disease. We present the case of a 65-year-old man with symptomatic severe aortic stenosis and concomitant IgG4 aortitis. The diagnosis was confirmed by IgG4 serum levels, positive positron emission computed tomography (PET-CT) scans, and pathology from mediastinal dissection. Surgical aortic valve replacement (SAVR) was unfeasible owing to extensive mediastinal fibrosis, and transcatheter aortic valve replacement (TAVR) was successfully performed. As ascending aorta access for SAVR in IgG4 aortitis…

Genetic variability among serotype G4 human rotavirus strains circulating in Palermo in the period 1985–2003

2005

Synthesis, characterization and DNA binding studies of potential G4 stabilizer metal complexes

2012

Ni(II) and Zn(II) Schiff Base complexes: B-DNA vs G4-DNA binding

2015

Interplay of three G‑quadruplex units in the KIT promoter

2019

The proto-oncogene KIT encodes for a tyrosine kinase receptor, which is a clinically validated target for treating gastrointestinal stromal tumors. The KIT promoter contains a G-rich domain within a relatively long sequence potentially able to form three adjacent G-quadruplex (G4) units, namely, K2, SP, and K1. These G4 domains have been studied mainly as single quadruplex units derived from short truncated sequences and are currently considered promising targets for anticancer drugs, alternatively to the encoded protein. Nevertheless, the information reported so far does not contemplate the interplay between those neighboring G4s in the context of the whole promoter, possibly thwarting dru…

Progressive multi-organ expression of immunoglobulin G4-related disease: A case report.

2012

A 63-year-old Caucasian man presented with a cholestatic syndrome, renal failure and arthralgias. A laboratory examination revealed high immunoglobulin G (IgG) and IgG4 levels (5.95 g/L; normal range: 0.08-1.4 g/L), pointing to a diagnosis of systemic IgG4-related disease, with definite radiological evidence of biliary and pancreatic expression, and plausible renal, articular, salivary and lacrimal glands involvement. Due to the rarity of the condition, there are currently no random control trials to point to the optimal therapeutic approach. The patient has been on steroid therapy with the subsequent introduction of azathioprine, with a complete resolution of all symptoms, a rapid reductio…