Structural factors controlling the transition between columnar hexagonal and helical mesophase in triphenylene liquid crystals.

A series of novel triphenylenes has been synthesised by a combination of palladium catalysed coupling, oxidative cyclisation, bromination and nucleophilic aromatic substitution. The new derivatives are designed to have structures which are intermediate between the known symmetrical materials hexakis(hexyloxy)triphenylene and hexakis(hexylthio)triphenylene. The compounds having four hexyloxy and two hexylthio substituents form only Colh mesophases. Triphenylenes having four hexylthio and two hexyloxy substituents also give Colh mesophases but 3,6-bis(hexyloxy)-2,7,10,11-tetrakis(hexylthio)triphenylene 5 is unique in that it cools into a stable, more ordered phase. The low temperature phase, which appears to be indefinitely stable at ambient temperature, is assumed to be helical based on transition enthalpy data

Roles and responsibilities of the student nurse mentor: an update.

Facilitating the learning of student nurses in the workplace is an integral role of the registered nurse. This article aims to provide an overview of the role and responsibilities of the mentor in supporting pre-registration nursing students in clinical practice. The professional obligations for the mentor to meet the Nursing and Midwifery Council (NMC) standards (NMC, 2008a) will be explored, including the ongoing requirements to keep up to date in mentoring practices. Some of the challenges within the role will be identified, including the importance of recognizing and supporting the failing student. Recent changes to the preparation requirements for sign-off mentors will be discussed. The article concludes by presenting the potential benefits to both the individual and the practice placement provider

Microneedle Array Design Determines the Induction of Protective Memory CD8+ T Cell Responses Induced by a Recombinant Live Malaria Vaccine in Mice

BACKGROUND: Vaccine delivery into the skin has received renewed interest due to ease of access to the immune system and microvasculature, however the stratum corneum (SC), must be breached for successful vaccination. This has been achieved by removing the SC by abrasion or scarification or by delivering the vaccine intradermally (ID) with traditional needle-and-syringes or with long microneedle devices. Microneedle patch-based transdermal vaccine studies have predominantly focused on antibody induction by inactivated or subunit vaccines. Here, our principal aim is to determine if the design of a microneedle patch affects the CD8(+) T cell responses to a malaria antigen induced by a live vaccine. METHODOLOGY AND FINDINGS: Recombinant modified vaccinia virus Ankara (MVA) expressing a malaria antigen was percutaneously administered to mice using a range of silicon microneedle patches, termed ImmuPatch, that differed in microneedle height, density, patch area and total pore volume. We demonstrate that microneedle arrays that have small total pore volumes induce a significantly greater proportion of central memory T cells that vigorously expand to secondary immunization. Microneedle-mediated vaccine priming induced significantly greater T cell immunity post-boost and equivalent protection against malaria challenge compared to ID vaccination. Notably, unlike ID administration, ImmuPatch-mediated vaccination did not induce inflammatory responses at the site of immunization or in draining lymph nodes. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that the design of microneedle patches significantly influences the magnitude and memory of vaccine-induced CD8(+) T cell responses and can be optimised for the induction of desired immune responses. Furthermore, ImmuPatch-mediated delivery may be of benefit to reducing unwanted vaccine reactogenicity. In addition to the advantages of low cost and lack of pain, the development of optimised microneedle array designs for the induction of T cell responses by live vaccines aids the development of solutions to current obstacles of immunization programmes

Single-cell multi-omics analysis of the immune response in COVID-19

Analysis of human blood immune cells provides insights into the coordinated response to viral infections such as severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). We performed single-cell transcriptome, surface proteome and T and B lymphocyte antigen receptor analyses of over 780,000 peripheral blood mononuclear cells from a cross-sectional cohort of 130 patients with varying severities of COVID-19. We identified expansion of nonclassical monocytes expressing complement transcripts (CD16+C1QA/B/C+) that sequester platelets and were predicted to replenish the alveolar macrophage pool in COVID-19. Early, uncommitted CD34+ hematopoietic stem/progenitor cells were primed toward megakaryopoiesis, accompanied by expanded megakaryocyte-committed progenitors and increased platelet activation. Clonally expanded CD8+ T cells and an increased ratio of CD8+ effector T cells to effector memory T cells characterized severe disease, while circulating follicular helper T cells accompanied mild disease. We observed a relative loss of IgA2 in symptomatic disease despite an overall expansion of plasmablasts and plasma cells. Our study highlights the coordinated immune response that contributes to COVID-19 pathogenesis and reveals discrete cellular components that can be targeted for therapy

Synthesis and properties of macrodiscotic triphenylenophthalocyanines

The synthesis and properties of substituted triphenylenophthalocyanines are described where the benzene rings of phthalocyanines are replaced by triphenylene units. The resulting materials are macrodiscotic in nature and show red-shifted absorption spectra and columnar mesophase behavior over a wide temperature range

Synthesis and characterisation of novel hexaalkoxytriphenylenes bearing an additional alkyl chain in the α-position

Exhaustive alkylation of hexahydroxytriphenylene results in production of significant quantities of a side product bearing one additional alkyl chain originating from C-alkylation. A series of these novel materials have been isolated and characterised to gain further insight on factors controlling mesophase formation in triphenylene discotics

Unexpected mesophase behaviour in novel triphenylene multi-alkenes

The first series of hexaalkenyloxytriphenylenes, where the unsaturation resides at the termini of the side chains, has been synthesised and characterised. Most interestingly, the synthesis of these alkenyloxytriphenylenes, by alkylation of hexahydroxytriphenylene, is found to yield additional products resulting from a single C-alkylation alongside exhaustive O-alkylation; surprisingly several homologues of these materials retain columnar mesophase behaviour