The Ca2+ transient as a feedback sensor controlling cardiomyocyte ionic conductances in mouse populations.

Conductances of ion channels and transporters controlling cardiac excitation may vary in a population of subjects with different cardiac gene expression patterns. However, the amount of variability and its origin are not quantitatively known. We propose a new conceptual approach to predict this variability that consists of finding combinations of conductances generating a normal intracellular Ca2+ transient without any constraint on the action potential. Furthermore, we validate experimentally its predictions using the Hybrid Mouse Diversity Panel, a model system of genetically diverse mouse strains that allows us to quantify inter-subject versus intra-subject variability. The method predicts that conductances of inward Ca2+ and outward K+ currents compensate each other to generate a normal Ca2+ transient in good quantitative agreement with current measurements in ventricular myocytes from hearts of different isogenic strains. Our results suggest that a feedback mechanism sensing the aggregate Ca2+ transient of the heart suffices to regulate ionic conductances

Ecophysiological traits of grasses: resolving the effects of photosynthetic pathway and phylogeny

C4 photosynthesis is an important example of convergent evolution in plants, having arisen in eudicots, monocots and diatoms. Comparisons between such diverse groups are confounded by phylogenetic and ecological differences, so that only broad generalisations can be made about the role of C4 photosynthesis in
determining ecophysiological traits. However, 60% of C4 species occur in the grasses (Poaceae) and molecular phylogenetic techniques confirm that there are between 8 and 17 independent origins of C4 photosynthesis in the Poaceae. In a screening experiment, we compared leaf physiology and growth traits across several major
independent C3 & C4 groups within the Poaceae, asking 1) which traits differ consistently between photosynthetic
types and 2) which traits differ consistently between clades within each photosynthetic type

Using Specialist Screening Practitioners (SSPs) to increase uptake of the Bowel Scope (Flexible Sigmoidoscopy) Screening Programme: a study protocol for a feasibility single-stage phase II trial

Background: The NHS Bowel Scope Screening (BSS) programme offers men and women aged 55 years a onceonly flexible sigmoidoscopy (FS), a test that can help reduce colorectal cancer (CRC) incidence and mortality. However, the benefits of BSS are contingent on uptake. This National Institute for Health Research-funded singlestage phase II trial will test the feasibility of using patient navigation (PN), an intervention that offers support to patients to overcome barriers to healthcare, to increase BSS uptake within a socially deprived area of England. Methods/design: All individuals invited for BSS at South Tyneside NHS Foundation Trust during the 6-month recruitment period will be invited to take part in the study. Consenting participants will be randomised to receive PN or usual care in a 2:1 ratio. PN involves non-attenders receiving a phone call from a Specialist Screening Practitioner (SSP) who will elicit reasons for non-attendance and offer educational, practical, and emotional support as needed. If requested by the patient, another appointment for BSS will then be arranged. We anticipate 30 % of participants will be non-attenders. Using A’Hern single-stage design, with 20 % significance level and 80 % power, at least 35 participants who receive PN need to subsequently attend for PN to be considered worthy of further investigation in a definitive trial. The primary outcome measure will be the number of participants in the PN group who re-book and attend their BSS appointment. A qualitative analysis of the PN transcripts, and interviews with the SSPs, will also be conducted, alongside a quantitative analysis of completed patient-reported experience questionnaires. An economic analysis will calculate the costs of delivering PN. Discussion: This feasibility study will be instrumental in deciding whether to conduct the first definitive trial of PN in BSS in England. If PN is subsequently shown to be cost-effective at increasing uptake of BSS, NHS policies could be modified to implement PN as a standard service. The results will be disseminated in peer-reviewed journals and at scientific conferences. Trial registration: International Standard Randomised Controlled Trial Number, ISRCTN1331475

Structural analysis of herpes simplex virus by optical super-resolution imaging.

Herpes simplex virus type-1 (HSV-1) is one of the most widespread pathogens among humans. Although the structure of HSV-1 has been extensively investigated, the precise organization of tegument and envelope proteins remains elusive. Here we use super-resolution imaging by direct stochastic optical reconstruction microscopy (dSTORM) in combination with a model-based analysis of single-molecule localization data, to determine the position of protein layers within virus particles. We resolve different protein layers within individual HSV-1 particles using multi-colour dSTORM imaging and discriminate envelope-anchored glycoproteins from tegument proteins, both in purified virions and in virions present in infected cells. Precise characterization of HSV-1 structure was achieved by particle averaging of purified viruses and model-based analysis of the radial distribution of the tegument proteins VP16, VP1/2 and pUL37, and envelope protein gD. From this data, we propose a model of the protein organization inside the tegument.This work was supported by grants from the Leverhulme Trust (grant RPG-2012-793), the Royal Society (University Research Fellowship to C.M.C.), the Engineering and Physical Sciences Research Council, UK (grant EP/H018301/1) and by the Medical Research Council (grant MR/K015850/1).This is the final published version. It first appeared at http://www.nature.com/ncomms/2015/150122/ncomms6980/full/ncomms6980.html

Patient experience of gastrointestinal endoscopy: Informing the development of the Newcastle ENDOPREM

Background Measuring patient experience is important for evaluating the quality of patient care, identifying aspects requiring improvement and optimising patient outcomes. Patient Reported Experience Measures (PREMs) should, ideally, be patient derived, however no such PREMs for gastrointestinal (GI) endoscopy exist. This study explored the experiences of patients undergoing GI endoscopy and CT colonography (CTC) in order to: identify aspects of care important to them; determine whether the same themes are relevant across investigative modalities; develop the framework for a GI endoscopy PREM. Methods Patients aged ≥18 years who had undergone oesophagogastroduodenoscopy (OGD), colonoscopy or CTC for symptoms or surveillance (but not within the national bowel cancer screening programme) in one hospital were invited to participate in semi-structured interviews. Recruitment continued until data saturation. Inductive thematic analysis was undertaken. Results 35 patients were interviewed (15 OGD, 10 colonoscopy, 10 CTC). Most patients described their experience chronologically, and five ‘procedural stages’ were evident: before attending for the test; preparing for the test; at the hospital, before the test; during the test; after the test. Six themes were identified: anxiety; expectations; choice & control; communication & information; comfort; embarrassment & dignity. These were present for all three procedures but not all procedure stages. Some themes were inter-related (eg, expectations & anxiety; communication & anxiety). Conclusion We identified six key themes encapsulating patient experience of GI procedures and these themes were evident for all procedures and across multiple procedure stages. These findings will be used to inform the development of the Newcastle ENDOPREM™

Barriers to colonoscopy in UK colorectal cancer screening programmes: Qualitative interviews with ethnic minority groups

OBJECTIVE: People from ethnic minority backgrounds are less likely to attend colonoscopy, following faecal immunochemical test screening, and are more likely to be diagnosed with colorectal cancer at an advanced stage as a result. The aim of this research was to explore the barriers and facilitators to attending colonoscopy, perceived by ethnic minority groups living in the United Kingdom. METHODS: Semi-structured online and telephone interviews were conducted with thirty men and women of Black-African(n=5), Black-Caribbean(n=5), South Asian(n=10) and White British(n=10) descent. Participants were eligible for screening, but had not necessarily been invited for colonoscopy. All interviews were conducted in the participant's first language and were assessed using Framework-analysis, in line with a conceptual framework developed from previous interviews with healthcare professionals. RESULTS: Five thematic groups of barriers and facilitators were developed: 'Locus of control', 'Cultural attitudes and beliefs', 'Individual beliefs, knowledge and personal experiences with colonoscopy and cancer', 'Reliance on family and friends' and 'Health concerns'. Differences were observed, between ethnic groups, for: 'Locus of control', 'Cultural attitudes and beliefs' and 'Reliance on family and friends'. Black and South Asian participants frequently described the decision to attend colonoscopy as lying with 'God' (Muslims, specifically), 'the doctor', or 'family' (Locus of control). Black and South Asian participants also reported relying on friends and family for 'language, transport and emotional support' (Reliance on family and friends). Black-African participants, specifically, described cancer as 'socially taboo' (Cultural attitudes and beliefs). CONCLUSIONS: The results highlight several targets for culturally-tailored interventions to make colonoscopy more equitable. This article is protected by copyright. All rights reserved

Were Fertile Crescent crop progenitors higher yielding than other wild species that were never domesticated?

During the origin of agriculture in the Fertile Crescent, the broad spectrum of wild plant species exploited by hunter-gatherers narrowed dramatically. The mechanisms responsible for this specialization and the associated domestication of plants are intensely debated. We investigated why some species were domesticated rather than others, and which traits they shared. We tested whether the progenitors of cereal and pulse crops, grown individually, produced a higher yield and less chaff than other wild grasses and legumes, thereby maximizing the return per seed planted and minimizing processing time. We compared harvest traits of species originating from the Fertile Crescent, including those for which there is archaeological evidence of deliberate collection. Unexpectedly, wild crop progenitors in both families had neither higher grain yield nor, in grasses, less chaff, although they did have larger seeds. Moreover, small-seeded grasses actually returned a higher yield relative to the mass of seeds sown. However, cereal progenitors had threefold fewer seeds per plant, representing a major difference in how seeds are packaged on plants. These data suggest that there was no intrinsic yield advantage to adopting large-seeded progenitor species as crops. Explaining why Neolithic agriculture was founded on these species, therefore, remains an important unresolved challenge

Characteristics of particle dispersion in the North Atlantic: An alternative interpretation of SOFAR float results

An analysis of published results on the dispersion behavior of SOFAR floats indicates a systematic depth dependence of the mixing length in the North Atlantic subtropical gyre. In contrast to the integral time scale, the length scale appears to be independent of eddy intensity in the thermocline (Lx, Ly ∼ 80, 45 km) and in the deep ocean (Lx ∼ Ly : 20 – 30 km). A similar decrease with depth is revealed by particle dispersion in an eddy-resolving circulation model and interpreted as an enhanced effect of wave behavior in the weaker, subthermocline flow. The only weak anisotropy of deep float dispersion suggests an influence of bottom roughness on the structure of eddy variability