Clonal evolution of Candida albicans, Candida glabrata and Candida dubliniensis at oral niche level in health and disease

This is the final version. Available on open access from Taylor & Francis via the DOI in this recordBackground:Candida species have long been recognised as aetiological agents of opportunistic infections of the oral mucosa, and more recently, as players of polymicrobial interactions driving caries, periodontitis and oral carcinogenesis. Methods: We studied the clonal structure of Candida spp. at oral niche resolution in patients (n = 20) with a range of oral health profiles over 22 months. Colonies from oral micro-environments were examined with multilocus sequencing typing. Results:Candida spp. identified were C. albicans, C. glabrata and C. dubliniensis. Increased propensity for micro-variations giving rise to multiple diploid strain types (DST), as a result of loss of heterozygosity, was observed among C. albicans clade 1 isolates compared to other clades. Micro-variations among isolates were also observed in C. dubliniensis contra to expectations of stable population structures for this species. Multiple sequence types were retrieved from patients without clinical evidence of oral candidosis, while single sequence types were isolated from oral candidosis patients. Conclusion: This is the first study to describe the clonal population structure, persistence and stability of Candida spp. at oral niche level. Future research investigating links between Candida spp. clonality and oral disease should recognise the propensity to micro-variations amongst oral niches in C. albicans and C. dubliniensis identified here.Medical Research Council (MRC)Wellcome Trus

No evidence of increased mutations in the germline of a group of British nuclear test veterans

Availability of data and materials: The dataset generated during this current study are available https://dataview.ncbi.nlm.nih.gov/object/PRJNA788492?reviewer=t65okctpc20o0jfr3n2rmf5n50Ethical Approval and consent to participate: The GCFT study was conducted in accordance with UK ethical framework and approved by the UK Health Research Authority (17/LO/0273).Copyright © The Author(s) 2022. The potential germline effects of radiation exposure to military veterans present at British nuclear tests in Australia and the South Pacific is of considerable interest. We analyzed germline mutations in 60 families of UK military personnel comprising 30 control and 30 nuclear test veterans (NTV). Using whole-genome sequencing we studied the frequency and spectra of de novo mutations to investigate the transgenerational effect of veterans’ (potential) exposure to radiation at nuclear bomb test sites. We find no elevation in total de novo single nucleotide variants, small insertion-deletions, structural variants or clustered mutations among the offspring of nuclear test veterans compared to those of control personnel. We did observe an elevated occurrence of single base substitution mutations within mutation signature SBS16, due to a subset of NTV offspring. The relevance of this elevation to potential exposure of veteran fathers and, future health risks, require further investigation. Overall, we find no evidence of increased mutations in the germline of a group of British nuclear test veterans. ISRCTN Registry 17461668.Nuclear Community Charity Fund (NCCF) through funds received by The Armed Forces Covenant Fund Trust under the Aged Veterans Fund Grant AVF16 (AM, MS, CG, CR, JP, RA, YD)

Real-Time Dynamics of Ca2+, Caspase-3/7, and Morphological Changes in Retinal Ganglion Cell Apoptosis under Elevated Pressure

Quantitative information on the dynamics of multiple molecular processes in individual live cells under controlled stress is central to the understanding of the cell behavior of interest and the establishment of reliable models. Here, the dynamics of the apoptosis regulator intracellular Ca2+, apoptosis effector caspase-3/7, and morphological changes, as well as temporal correlation between them at the single cell level, are examined in retinal gangling cell line (differentiated RGC-5 cells) undergoing apoptosis at elevated hydrostatic pressure using a custom-designed imaging platform that allows long-term real-time simultaneous imaging of morphological and molecular-level physiological changes in large numbers of live cells (beyond the field-of-view of typical microscopy) under controlled hydrostatic pressure. This examination revealed intracellular Ca2+ elevation with transient single or multiple peaks of less than 0.5 hour duration appearing at the early stages (typically less than 5 hours after the onset of 100 mmHg pressure) followed by gradual caspase-3/7 activation at late stages (typically later than 5 hours). The data reveal a strong temporal correlation between the Ca2+ peak occurrence and morphological changes of neurite retraction and cell body shrinkage. This suggests that Ca2+ elevation, through its impact on ion channel activity and water efflux, is likely responsible for the onset of apoptotic morphological changes. Moreover, the data show a significant cell-to-cell variation in the onset of caspase-3/7 activation, an inevitable consequence of the stochastic nature of the underlying biochemical reactions not captured by conventional assays based on population-averaged cellular responses. This real-time imaging study provides, for the first time, statistically significant data on simultaneous multiple molecular level changes to enable refinements and testing of models of the dynamics of mitochondria-mediated apoptosis. Further, the platform developed and the approach has direct significance to the study of a variety of signaling pathway phenomena

Translational models for vascular cognitive impairment: a review including larger species.

BACKGROUND: Disease models are useful for prospective studies of pathology, identification of molecular and cellular mechanisms, pre-clinical testing of interventions, and validation of clinical biomarkers. Here, we review animal models relevant to vascular cognitive impairment (VCI). A synopsis of each model was initially presented by expert practitioners. Synopses were refined by the authors, and subsequently by the scientific committee of a recent conference (International Conference on Vascular Dementia 2015). Only peer-reviewed sources were cited. METHODS: We included models that mimic VCI-related brain lesions (white matter hypoperfusion injury, focal ischaemia, cerebral amyloid angiopathy) or reproduce VCI risk factors (old age, hypertension, hyperhomocysteinemia, high-salt/high-fat diet) or reproduce genetic causes of VCI (CADASIL-causing Notch3 mutations). CONCLUSIONS: We concluded that (1) translational models may reflect a VCI-relevant pathological process, while not fully replicating a human disease spectrum; (2) rodent models of VCI are limited by paucity of white matter; and (3) further translational models, and improved cognitive testing instruments, are required

The Concise Guide to PHARMACOLOGY 2013/14: overview.

The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties from the IUPHAR database. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. This compilation of the major pharmacological targets is divided into seven areas of focus: G protein-coupled receptors, ligand-gated ion channels, ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors & Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and GRAC and provides a permanent, citable, point-in-time record that will survive database updates

An optimised 3 M KCl salt-bridge technique used to measure and validate theoretical liquid junction potential values in patch-clamping and electrophysiology

Accurate potential measurements in electrophysiological experiments require correction for liquid junction potentials (LJPs), and, in patch-clamping especially, these can often be ~5-10 mV or more. They can be either calculated, if ion mobilities are known, or measured directly. We describe an optimised system to directly measure LJPs with a patch-clamp amplifier, using as a reference electrode, a freshly-cut 3 M KCl-agar salt-bridge (in polyethylene tubing) with its tip cut off by at least 5 mm during solution changes to eliminate its solution-history-dependent effects. We quantify such history-dependent effects and complement this with a de-novo theoretical analysis of salt diffusion to and from the salt-bridge. Our analysis and experimental results validate the optimised methodology for measuring LJPs, and the use of the Henderson equation for accurately calculating them. The use of this equation is also assessed and generally validated in the light of rigorous Nernst-Planck-Poisson and other numerical simulations and analytical studies of LJPs over recent decades. Digitizing, recording and amplifying the measured potentials increases their accuracy. The measured potentials still need correction for small, well-defined calculable, shifts in LJPs at the 3 M KCl-agar reference. Using this technique, we have measured changes in LJPs for diluted solutions of NaCl, LiCl, KCl, CsCl and NaF, obtaining excellent agreement within ±0.1 mV of predicted values, calculated using ion activities. Our de novo LJP measurements of biionic combinations of the above undiluted salts, and NaI and NaF (with halide anions I- and F -), generally also gave excellent agreement with predicted values. © 2013 European Biophysical Societies' Association