Supramolecular multiplexes from collagen mimetic peptide-PNA(GGG) conjugates and C-rich DNA: pH-induced reversible switching from triplex-duplex to triplex--motif.

Peptides are well known for forming nanoparticles, while DNA duplexes, triplexes and tetraplexes create rigid nanostructures. Accordingly, the covalent conjugation of peptides to DNA/RNA produces hybrid self-assembling features and may lead to interesting nano-assemblies distinct from those of their individual components. Herein, we report the preparation of a collagen mimetic peptide incorporating lysine in its backbone, with alkylamino side chains radially conjugated with G-rich PNA [collagen-(PNA-GGG)].

Supramolecular polyplexes from Janus peptide nucleic acids (bm-PNA-G5): self-assembled bm-PNA G-quadruplex and its tetraduplex with DNA.

Nucleic acids (DNA and RNA) can form diverse secondary structures ranging from hairpins to duplex, triplex, G4-tetraplex and C4-i-motifs. Many of the DNA analogues designed as antisense oligonucleotides (ASO) are also adept at embracing such folded structures, although to different extents with altered stabilities. One such analogue, peptide nucleic acid (PNA), which is uncharged and achiral, forms hybrids with complementary DNA/RNA with greater stability and specificity than DNA:DNA/RNA hybrids.

Dynamics of terminal fraying-peeling and hydrogen bonds dictates the sequential . cooperative melting pathways of nanoscale DNA and PNA triplexes.

Peptide nucleic acids (PNAs) are charge-neutral synthetic DNA/RNA analogues. In many aspects of biology and biotechnology, the details of DNA and PNA melting reaction coordinates are crucial, and their associative/dissociative details remain inadequately understood. In the current study, we have attempted to gain insights into comparative melting pathways and binding affinity of iso-sequences of an 18-mer PNA-DNA-PNA triplex and the analogous DNA-DNA-DNA triplex, and DNA-DNA and PNA-DNA duplexes.

Adrenocortical suppression in children with nephrotic syndrome treated with corticosteroids.

Background: Children with nephrotic syndrome are exposed to alternate day steroids for prolonged periods and this poses the need for evaluation of adrenocortical suppression using the adrenocorticotropic hormone (ACTH) stimulation test.

Methods: This cross-sectional study enrolled children (2-18 years) both with steroid sensitive nephrotic syndrome (SSNS) (n = 27) and steroid resistant (SRNS) (n = 25); those on daily prednisolone or having serious bacterial infections or hospitalized were excluded. The primary objective was to determine prevalence of adrenocortical suppression in those on low dose alternate day steroids for more than 8 weeks or having received > 2 mg/kg/d for > 2 weeks in the past 1 year and currently in remission.

Performance of Biopsy Tools in Procurement of Lung Tissue in Robot-Assisted Peripheral Navigation: A Comparison.

Introduction: Robot-assisted navigation bronchoscopy (RANB) has been gaining traction as a new technology for minimally invasive biopsies of peripheral pulmonary lesions (PPLs). Cryobiopsy is an established method of procuring satisfactory lung tissues and can be safely paired with RANB. While some studies have evaluated the diagnostic accuracy and yield of this procedure, there is limited data on the utility of various biopsy tools, the sequence of use and differences in tissue characteristics based on the sampling techniques.

Safety, Tolerability, and Pharmacokinetics of Single and Multiple Ascending Intravenous Infusions of PF-07304814 (Lufotrelvir) in Participants Hospitalized With COVID-19.

Background: An urgent need remains for antiviral therapies to treat patients hospitalized with COVID-19. PF-07304814-the prodrug (lufotrelvir) and its active moiety (PF-00835231)-is a potent inhibitor of the SARS-CoV-2 3CL protease.

Method: Eligible participants were 18 to 79 years old and hospitalized with confirmed COVID-19.

Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle.

Film cooling as applied to rocket nozzles is analyzed numerically with emphasis on the assessment of the effect of the mixing of coolant with the hot stream. Cooling performance, as characterized by cooling effectiveness, is studied for three different coolants in the three-dimensional, turbulent flow field of a supersonic convergent-divergent nozzle operating with a hot stream temperature of 2500 K over a range of blowing ratios. The coolant stream is injected tangentially into the mainstream using a diffuser-type injector.

Gemdimethyl Peptide Nucleic Acids (α/β/γ-PNA): E/Z-Rotamers Influence the Selectivity in the Formation of Parallel/Antiparallel -PNA:DNA/RNA Duplexes.

Peptide nucleic acids (PNAs) consist of an aminoethylglycine () backbone to which the nucleobases are linked through a tertiary amide group and bind to complementary DNA/RNA in a sequence-specific manner. The flexible backbone has been the target for several chemical modifications of the PNA to improve its properties such as specificity, solubility, etc. PNA monomers exhibit a mixture of two rotamers (Z/E) arising from the restricted rotation around the tertiary amide N-CO bond.

Aza-PNA: Engineering E-Rotamer Selectivity Directed by Intramolecular H-bonding.

The replacement of α(CH) by NH in monomers of standard PNA and its homologue β- PNA leads to respective -PNA monomers ( and ) in which the NH can form either an 8-membered H-bonded ring with folding of the backbone (DMSO and water) or a 5-membered NH─αCO (water) to stabilize -type rotamers. Such -PNA oligomers with exclusive rotamers and intraresidue backbone H-bonding can modulate its DNA/RNA binding and assembling properties.

: 2022 Spring Forward, 2021 Look Back .

has entered its seventh year of publishing since the journal was launched in 2016. We are pleased to present an update and summarize 's new plans and offerings in 2022 and look back and share the key journal statistics from 2021 while featuring some of its excellent published content. We take this opportunity to thank our global pool of reviewers for their continued voluntary and invaluable support in serving the journal and their assistance in maintaining the quality of our published content.

Silver soldering of PNA:DNA duplexes: assembly of a triple duplex from bimodal PNAs with all-C on one face.

DNA:bm-PNA duplexes endowed with all-C on either the t-amide or triazole face and mixed base sequence on the other face can be welded with silver ions through C:Ag:C connects to give triple duplexes in one complex. The interplay of WC and Ag-mediated duplexes leads to synergistic stability effects on both duplexes and the complex.

Cone Beam CT Guidance Improves Transbronchial Lung Cryobiopsy Safety.

Introduction: Determining the cause of diffuse parenchymal lung disease (DPLD) is challenging. While surgical lung biopsy has been the standard approach, transbronchial lung cryobiopsy (TBLC) represents a minimally invasive alternative with an acceptable safety profile and reasonable accuracy. In this study, we prospectively assessed whether the use of cone beam CT (CBCT) coupled with a novel bronchoscope holder and prophylactic administration of vasoconstricting medications decreases potential complications and improves diagnostic accuracy when performing TBLC.

Endobronchial Leiomyoma: A case report with cryoprobe extraction and review of literature.

Large airway tumors are uncommon, accounting for about 0.6% of all pulmonary tumors [[1], [2], [3]]. The majority of these tumors (80-90%) are malignant, represented primarily by squamous cell carcinoma and adenoid cystic carcinoma [2,4].

Molecular Assembly of Triplex of Duplexes from Homothyminyl-Homocytosinyl Cγ(/)-Bimodal Peptide Nucleic Acids with dA/dG and the Cell Permeability of Bimodal Peptide Nucleic Acids.

Peptide nucleic acids (PNAs) are analogues of DNA with a neutral acyclic polyamide backbone containing nucleobases attached through a t-amide link on repeating units of aminoethylglycine (). They bind to complementary DNA or RNA in a sequence-specific manner to form duplexes with higher stablity than DNA:DNA and DNA:RNA hybrids. We have recently explored a new type of PNA termed bimodal PNA (-PNA) designed with two nucleobases per repeating unit of PNA oligomer and attached at Cα or Cγ of each unit through a spacer sidechain.

Gem-dimethyl peptide nucleic acid (α/β/γ--PNA) monomers: synthesis and the role of -substituents in preferential stabilisation of /-rotamers.

The flexible backbone of aminoethylglycine (aeg) PNA upon substitution becomes sterically constrained to enable conformational pre-organization for preferential binding to DNA or RNA. The bulky gem-dimethyl (gdm) substituent on carbons adjacent to the t-amide sidechain either at Cα (glycyl) or Cβ/Cγ (aminoethylene) sides may influence the Z/E rotamer ratio arising from a restricted rotation around the t-amide bond. Employing 2D NMR (NOESY), it is shown here that the Cα-gdm-PNA-T monomer exhibits exclusively the Z-rotamer, while the Cβ-gdm-PNA-T monomer shows only the E-rotamer.