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The clinical effectiveness of screening is highly dependent on uptake. Previous randomised controlled trials suggest that non-participant reminders, which highlight the opportunity to re-book an appointment, can improve participation. The present analysis examines the impact of implementing these reminders within the English Flexible Sigmoidoscopy (FS) Screening Programme, which offers once-only FS screening to adults aged 55–59 years.We assessed the screening status of 26,339 individuals invited for once-only FS screening in England. A total of 10,952 (41.6%) had attended screening, and were subsequently ineligible. The remaining 15,387 had not attended screening, and were selected to receive a reminder, 1–2 years after their invitation. Descriptive statistics were used to assess the increase in uptake and the adenoma detection rate (ADR) of those who self-referred, six months after the delivery of the final reminder. Pearson’s Chi-Square was used to compare the ADR between those who attended when invited and those who self-referred.Of the 15,387 adults eligible to receive a reminder, 13,626 (88.6%) were sent a reminder as intended (1,761 were not sent a reminder, due to endoscopy capacity). Of these, 8.0% (n = 1,086) booked and attended an appointment, which equated to a 4.1% increase in uptake from 41.6% at baseline, to 45.7% at follow-up. The ADR was significantly higher for those who self-referred, compared with those who attended when invited (13.3% and 9.5%, respectively; X2 = 16.138, p = 0.000059).The implementation of non-participant reminders led to a moderate increase in uptake. Implementing non-participant reminders could help mitigate the negative effects of COVID-19 on uptake.

Abstract Malaria parasites such as Plasmodium falciparum have exerted formidable selective pressures on the human genome. Of the human genetic variants associated with malaria protection, beta thalassaemia (a haemoglobinopathy) was the earliest to be associated with malaria prevalence. However, the malaria protective properties of beta thalassaemic erythrocytes remain unclear. Here we studied the mechanics and surface protein expression of beta thalassaemia heterozygous erythrocytes, measured their susceptibility to P. falciparum invasion, and calculated the energy required for merozoites to invade them. We found invasion-relevant differences in beta thalassaemic cells versus matched controls, specifically: elevated membrane tension, reduced bending modulus, and higher levels of expression of the major invasion receptor basigin. However, these differences acted in opposition to each other with respect to their likely impact on invasion, and overall we did not observe beta thalassaemic cells to have lower P. falciparum invasion efficiency for any of the strains tested.

Large epidemiological studies often require sample transportation and storage, presenting unique considerations when applying advanced lipidomics techniques. The goal of this study was to acquire lipidomics data on plasma and serum samples stored at potential preanalytical conditions (e.g., thawing, extracting, evaporating), systematically monitoring lipid species for a period of one month. Split aliquots of 10 plasma samples and 10 serum samples from healthy individuals were kept in three temperature-related environments: refrigerator, laboratory benchtop, or heated incubator. Samples were analyzed at six different time points over 28 days using a Bligh & Dyer lipid extraction protocol followed by direct infusion into a lipidomics platform using differential mobility with tandem mass spectrometry. The observed concentration changes over time were evaluated relative to method and inter-individual biological variability. In addition, to evaluate the effect of lipase enzyme levels on concentration changes during storage, we compared corresponding fasting and post-prandial plasma samples collected from 5 individuals. Based on our data, a series of low abundance free fatty acid (FFA), diacylglycerol (DAG), and cholesteryl ester (CE) species were identified as potential analytical markers for degradation. These FFA and DAG species are typically produced by endogenous lipases from numerous triacylglycerols (TAGs), and certain high abundance phosphatidylcholines (PCs). The low concentration CEs, which appeared to increase several fold, were likely mass-isobars from oxidation of other high concentration CEs. Although the concentration changes of the high abundant TAG, PC, and CE precursors remained within method variability, the concentration trends of FFA, DAG, and oxidized CE products should be systematically monitored over time to inform analysts about possible pre-analytical biases due to degradation in the study sample sets.

Abstract Background Winter numbers of the northwest European population of Bewick’s Swans (Cygnus columbianus bewickii) declined recently by c. 40%. During the same period, numbers of two sympatric and ecologically-similar congeners, the Mute Swan (Cygnus olor) and Whooper Swan (Cygnus cygnus) showed increases or stability. It has been suggested that these opposing population trends could have a causal relationship, as Mute and Whooper Swans are larger and competitively dominant to Bewick’s Swans in foraging situations. If so, effects of competition of Mute and Whooper Swans on Bewick’s Swans should be detectable as measurable impacts on behaviour and energetics. Methods Here, we studied the diurnal behaviour and energetics of 1083 focal adults and first-winter juveniles (“cygnets”) of the three swan species on their winter grounds in eastern England. We analysed video recordings to derive time-activity budgets and these, together with estimates of energy gain and expenditure, were analysed to determine whether individual Bewick’s Swans altered the time spent on key behaviours when sharing feeding habitat with other swan species, and any consequences for their energy expenditure and net energy gain. Results All three swan species spent a small proportion of their total time (0.011) on aggressive interactions, and these were predominantly intraspecific (≥ 0.714). Mixed-effects models indicated that sharing feeding habitat with higher densities of Mute and Whooper Swans increased the likelihood of engaging in aggression for cygnet Bewick’s Swans, but not for adults. Higher levels of interspecific competition decreased the time spent by Bewick’s Swan cygnets on foraging, whilst adults showed the opposite pattern. When among low densities of conspecifics (

The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein-independent substrate (CO2) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe4S4 cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe4S4 cluster of the nitrogenase Fe protein when potassium selenocyanate is used as the selenium source, an unexpected result as the Fe protein cluster is not traditionally perceived as a site of substrate binding within nitrogenase. The observed chalcogenide exchange illustrates that this Fe4S4 cluster is capable of core substitution reactions under certain conditions, adding to the Fe protein’s repertoire of unique properties.

Research in sickle cell anemia (SCA) has used, with limited race-matched control data, binary categorization of patients according to the presence or absence of silent cerebral infarction (SCI). SCI have primarily been identified using low-resolution MRI, with radiological definitions varying in lesion length and the requirement for abnormality on both fluid attenuated inversion recovery (FLAIR) and T1-weighted images. We aimed to assess the effect of published SCI definitions on global, regional, and lobar lesion metrics and their value in predicting cognition. One hundred and six patients with SCA and 48 controls aged 8–30 years underwent 3T MRI with a high-resolution FLAIR sequence and Wechsler cognitive assessment. Prevalence, number, and volume of lesions were calculated using a semi-automated pipeline for SCI defined as: (1) Liberal: any length (L-SCI); (2) Traditional: >3 mm in greatest dimension (T-SCI); (3) Restrictive; >3 mm in greatest dimension with a corresponding T1-weighted hypo-intensity (R-SCI). Globally, as hypothesized, there were large effects of SCI definition on lesion metrics in patients and controls, with prevalence varying from 24–42% in patients, and 4–23% in controls. However, contrary to hypotheses, there was no effect of any global metric on cognition. Regionally, there was a consistent distribution of SCI in frontal and parietal deep and juxta-cortical regions across definitions and metrics in patients, but no consistent distribution in controls. Effects of regional SCI metrics on cognitive performance were of small magnitude; some were paradoxical. These findings expose the challenges associated with the widespread use of SCI presence as a biomarker of white-matter injury and cognitive dysfunction in cross-sectional high-resolution MRI studies in patients with SCA. The findings indicate that with high-resolution MRI: (1) radiological definitions have a large effect on resulting lesion groups, numbers, and volumes; (2) there is a non-negligible prevalence of lesions in young healthy controls; and (3) at the group-level, there is no cross-sectional association between global lesion metrics and general cognitive impairment irrespective of lesion definition and metric. With high-resolution multi-modal MRI, the dichotomy of presence or absence of SCI does not appear to be a sensitive biomarker for the detection of functionally significant pathology; the search for appropriate endpoints for clinical treatment trials should continue.

Abstract Background Environmental DNA (eDNA) metabarcoding is revolutionizing biodiversity monitoring, but has unrealized potential for ecological hypothesis generation and testing. Aims Here, we validate this potential in a large‐scale analysis of vertebrate community data generated by eDNA metabarcoding of 532 UK ponds. Materials & Methods We test biotic associations between the threatened great crested newt (Triturus cristatus) and other vertebrates as well as abiotic factors influencing T. cristatus detection at the pondscape. Furthermore, we test the status of T. cristatus as an umbrella species for pond conservation by assessing whether vertebrate species richness is greater in ponds with T. cristatus and higher T. cristatus Habitat Suitability Index (HSI) scores. Results Triturus cristatus detection was positively correlated with amphibian and waterfowl species richness. Specifically, T. cristatus was positively associated with smooth newt (Lissotriton vulgaris), common coot (Fulica atra), and common moorhen (Gallinula chloropus), but negatively associated with common toad (Bufo bufo). Triturus cristatus detection did not significantly decrease as fish species richness increased, but negative associations with common carp (Cyprinus carpio), three‐spined stickleback (Gasterosteus aculeatus), and ninespine stickleback (Pungitius pungitius) were identified. Triturus cristatus detection was negatively correlated with mammal species richness, and T. cristatus was negatively associated with gray squirrel (Sciurus carolinensis). Triturus cristatus detection was negatively correlated with larger pond area, presence of inflow, and higher percentage of shading, but positively correlated with HSI score, supporting its application to T. cristatus survey. Vertebrate species richness was significantly higher in T. cristatus ponds and broadly increased as T. cristatus HSI scores increased. Discussion We reaffirm reported associations (e.g., T. cristatus preference for smaller ponds) but also provide novel insights, including a negative effect of pond inflow on T. cristatus. Conclusion Our findings demonstrate the prospects of eDNA metabarcoding for ecological hypothesis generation and testing at landscape scale, and dramatic enhancement of freshwater conservation, management, monitoring, and research.

Previous studies have pointed to a role for regional cerebral hemodynamic stress in neurological complications in patients with sickle cell anemia (SCA), with watershed regions identified as particularly at risk of ischemic tissue injury. Using single- and multi-inflow time (TI) arterial spin labeling sequences (ASL) in 94 patients with SCA and 42 controls, the present study sought to investigate cerebral blood flow (CBF) and bolus arrival times (BAT) across gray matter, white matter with early arrival times, and in individual watershed areas (iWSAs). In iWSAs, associations between hemodynamic parameters, lesion burden, white matter integrity, and general cognitive performance were also explored. In patients, increases in CBF and reductions in BAT were observed in association with reduced arterial oxygen content across gray matter and white matter with early arrival times using both sequences (all p < 0.001, d = −1.55–−2.21). Across iWSAs, there was a discrepancy between sequences, with estimates based on the single-TI sequence indicating higher CBF in association with reduced arterial oxygen content in SCA patients, and estimates based on the multi-TI sequence indicating no significant between-group differences or associations with arterial oxygen content. Lesion burden was similar between white matter with early arrival times and iWSAs in both patients and controls, and using both sequences, only trend-level associations between iWSA CBF and iWSA lesion burden were observed in patients. Further, using the multi-TI sequence in patients, increased iWSA CBF was associated with reduced iWSA microstructural tissue integrity and slower processing speed. Taken together, the results highlight the need for researchers to consider BAT when estimating CBF using single-TI sequences. Moreover, the findings demonstrate the feasibility of multi-TI ASL for objective delineation of iWSAs and for detection of regional hemodynamic stress that is associated with reduced microstructural tissue integrity and slower processing speed. This technique may hold promise for future studies and treatment trials.

The ATP binding cassette (ABC) transporter of mitochondria (Atm) from Arabidopsis thaliana (AtAtm3) has been implicated in the maturation of cytosolic iron-sulfur proteins and heavy metal detoxification, plausibly by exporting glutathione derivatives. Using single-particle cryo-electron microscopy, we have determined four structures of AtAtm3 in three different conformational states: two inward-facing conformations (with and without bound oxidized glutathione [GSSG]), together with closed and outward-facing states stabilized by MgADP-VO4. These structures not only provide a structural framework for defining the alternating access transport cycle, but also reveal the paucity of cysteine residues in the glutathione binding site that could potentially form inhibitory mixed disulfides with GSSG. Despite extensive efforts, we were unable to prepare the ternary complex of AtAtm3 containing both GSSG and MgATP. A survey of structurally characterized type IV ABC transporters that includes AtAtm3 establishes that while nucleotides are found associated with all conformational states, they are effectively required to stabilize occluded, closed, and outward-facing conformations. In contrast, transport substrates have only been observed associated with inward-facing conformations. The absence of structures with dimerized nucleotide binding domains containing both nucleotide and transport substrate suggests that this form of the ternary complex exists only transiently during the transport cycle.

Nicotinic partial agonists provide an accepted aid for smoking cessation and thus contribute to decreasing tobacco-related disease. Improved drugs constitute a continued area of study. However, there remains no reductionist method to examine the cellular and subcellular pharmacokinetic properties of these compounds in living cells. Here, we developed new intensity-based drug-sensing fluorescent reporters (iDrugSnFRs) for the nicotinic partial agonists dianicline, cytisine, and two cytisine derivatives – 10-fluorocytisine and 9-bromo-10-ethylcytisine. We report the first atomic-scale structures of liganded periplasmic binding protein-based biosensors, accelerating development of iDrugSnFRs and also explaining the activation mechanism. The nicotinic iDrugSnFRs detect their drug partners in solution, as well as at the plasma membrane (PM) and in the endoplasmic reticulum (ER) of cell lines and mouse hippocampal neurons. At the PM, the speed of solution changes limits the growth and decay rates of the fluorescence response in almost all cases. In contrast, we found that rates of membrane crossing differ among these nicotinic drugs by >30-fold. The new nicotinic iDrugSnFRs provide insight into the real-time pharmacokinetic properties of nicotinic agonists and provide a methodology whereby iDrugSnFRs can inform both pharmaceutical neuroscience and addiction neuroscience.

NmMetQ is a substrate-binding protein (SBP) from Neisseria meningitidis that has been identified as a surface-exposed candidate antigen for meningococcal vaccines. However, this location for NmMetQ challenges the prevailing view that SBPs in Gram-negative bacteria are localized to the periplasmic space to promote interaction with their cognate ABC transporter embedded in the bacterial inner membrane. To elucidate the roles of NmMetQ, we characterized NmMetQ with and without its cognate ABC transporter (NmMetNI). Here, we show that NmMetQ is a lipoprotein (lipo-NmMetQ) that binds multiple methionine analogs and stimulates the ATPase activity of NmMetNI. Using single-particle electron cryo-microscopy, we determined the structures of NmMetNI in the presence and absence of lipo-NmMetQ. Based on our data, we propose that NmMetQ tethers to membranes via a lipid anchor and has dual function and localization, playing a role in NmMetNI-mediated transport at the inner membrane and moonlighting on the bacterial surface.

Abstract Objective Analysis of environmental DNA (eDNA) is a method that has been used for the detection of various species within water bodies. The great crested newt (Triturus cristatus) has a short eDNA survey season (mid-April to June). Here we investigate whether this season could be extended into other months using the current methodology as stipulated by Natural England. Results Here we present data to show that in monthly water samples taken from two ponds (March 2014–February 2015) we were able to detect great crested newt DNA in all months in at least one of the ponds. Similar levels of great crested newt eDNA (i.e. highly positive identification) were detected through the months of March–August, suggesting it may be possible to extend the current survey window. In order to determine how applicable these observations are for ponds throughout the rest of the UK, further work in multiple other ponds over multiple seasons is suggested. Nevertheless, the current work clearly demonstrates, in two ponds, the efficacy and reproducibility of eDNA detection for determining the presence of great crested newts.

The advancement of underrepresented minority and women PhD students to elite postdoctoral and faculty positions in the STEM fields continues to lag that of majority males, despite decades of efforts to mitigate bias and increase opportunities for students from diverse backgrounds. In 2015, the National Science Foundation Alliance for Graduate Education and the Professoriate (NSF AGEP) California Alliance (Berkeley, Caltech, Stanford, UCLA) conducted a wide-ranging survey of graduate students across the mathematical, physical, engineering, and computer sciences in order to identify levers to improve the success of PhD students, and, in time, improve diversity in STEM leadership positions, especially the professoriate. The survey data were interpreted via path analysis, a method that identifies significant relationships, both direct and indirect, among various factors and outcomes of interest. We investigated two important outcomes: publication rates, which largely determine a new PhD student's competitiveness in the academic marketplace, and subjective well-being. Women and minority students who perceived that they were well-prepared for their graduate courses and accepted by their colleagues (faculty and fellow students), and who experienced well-articulated and structured PhD programs, were most likely to publish at rates comparable to their male majority peers. Women PhD students experienced significantly higher levels of distress than their male peers, both majority and minority, while both women and minority student distress levels were mitigated by clearly-articulated expectations, perceiving that they were well-prepared for graduate level courses, and feeling accepted by their colleagues. It is unclear whether higher levels of distress in women students is related directly to their experiences in their STEM PhD programs. The findings suggest that mitigating factors that negatively affect diversity should not, in principle, require the investment of large resources, but rather requires attention to the local culture and structure of individual STEM PhD programs.

Prions are an enigma amongst infectious disease agents as they lack a genome yet confer specific pathologies thought to be dictated mainly, if not solely, by the conformation of the disease form of the prion protein (PrPSc). Prion diseases affect humans and animals, the latter including the food-producing ruminant species cattle, sheep, goats and deer. Importantly, it has been shown that the disease agent of bovine spongiform encephalopathy (BSE) is zoonotic, causing variant Creutzfeldt Jakob disease (vCJD) in humans. Current diagnostic tests can distinguish different prion types and in food-producing animals these focus on the differentiation of BSE from the non-zoonotic agents. Whilst BSE cases are now rare, atypical forms of both scrapie and BSE have been reported, as well as two types of chronic wasting disease (CWD) in cervids. Typing of animal prion isolates remains an important aspect of prion diagnosis and is now becoming more focused on identifying the range of prion types that are present in food-producing animals and also developing tests that can screen for emerging, novel prion diseases. Here, we review prion typing methodologies in light of current and emerging prion types in food-producing animals.

Genetic variants at three quantitative trait loci (QTL) for fetal haemoglobin (HbF), BCL11A, HBS1L-MYB and the β-globin gene cluster, have attracted interest as potential targets of therapeutic strategies for HbF reactivation in sickle cell anaemia (SCA). We carried out the first systematic evaluation of critical single nucleotide polymorphisms at these disease modifier loci in Nigerian patients with SCA. Common variants for BCL11A and HBS1L-MYB were strongly associated with HbF levels. At both loci, secondary association signals were detected, illustrating the mapping resolution attainable in this population. For BCL11A, the two independent sites of association were represented by rs1427407 (primary site, p = 7.0 x 10(-10)) and rs6545816 (secondary site, conditioned on rs1427407: p = 0.02) and for HBS1L-MYB by rs9402686 (HMIP-2B, p = 1.23 x 10(-4)) and rs66650371 (HMIP-2A, p = 0.002). Haplotype analysis revealed similarities in the genetic architecture of BCL11A and HBS1L-MYB in Nigerian patients. Variants at both loci also alleviated anaemia. The variant allele for the γ globin gene promoter polymorphism XmnI-HBG2 was too infrequent in our patients to be evaluated in this relatively small study. Studying the large and diverse SCA patient populations in African countries such as Nigeria will be key for a clearer understanding of how these loci work and for the discovery of new disease modifier genes.

Lipoproteins are complex molecular assemblies that are key participants in the intricate cascade of extracellular lipid metabolism with important consequences in the formation of atherosclerotic lesions and the development of cardiovascular disease. Multiplexed mass spectrometry (MS) techniques have substantially improved the ability to characterize the composition of lipoproteins. However, these advanced MS techniques are limited by traditional pre-analytical fractionation techniques that compromise the structural integrity of lipoprotein particles during separation from serum or plasma. In this work, we applied a highly effective and gentle hydrodynamic size based fractionation technique, asymmetric flow field-flow fractionation (AF4), and integrated it into a comprehensive tandem mass spectrometry based workflow that was used for the measurement of apolipoproteins (apos A-I, A-II, A-IV, B, C-I, C-II, C-III and E), free cholesterol (FC), cholesterol esters (CE), triglycerides (TG), and phospholipids (PL) (phosphatidylcholine (PC), sphingomyelin (SM), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and lysophosphatidylcholine (LPC)). Hydrodynamic size in each of 40 size fractions separated by AF4 was measured by dynamic light scattering. Measuring all major lipids and apolipoproteins in each size fraction and in the whole serum, using total of 0.1 ml, allowed the volumetric calculation of lipoprotein particle numbers and expression of composition in molar analyte per particle number ratios. Measurements in 110 serum samples showed substantive differences between size fractions of HDL and LDL. Lipoprotein composition within size fractions was expressed in molar ratios of analytes (A-I/A-II, C-II/C-I, C-II/C-III. E/C-III, FC/PL, SM/PL, PE/PL, and PI/PL), showing differences in sample categories with combinations of normal and high levels of Total-C and/or Total-TG. The agreement with previous studies indirectly validates the AF4-LC-MS/MS approach and demonstrates the potential of this workflow for characterization of lipoprotein composition in clinical studies using small volumes of archived frozen samples.

Metastasis is associated with poor prognosis in breast cancer. Although some studies suggest beta-blockers increase survival by delaying metastasis, others have been discordant. This study provides both insights into the anomalous findings and identifies potential biomarkers that may be treatment targets. Cell line models of basal-type and oestrogen receptor-positive breast cancer were profiled for basal levels of adrenoceptor gene/protein expression, and β2-adrenoceptor mediated cell behaviour including migration, invasion, adhesion, and survival in response to adrenoceptor agonist/antagonist treatment. Protein profiling and histology identified biomarkers and drug targets. Baseline levels of adrenoceptor gene expression are higher in basal-type rather than oestrogen receptor-positive cancer cells. Norepinephrine (NE) treatment increased invasive capacity in all cell lines but did not increase proliferation/survival. Protein profiling revealed the upregulation of the pro-metastatic gene Ly6/PLAUR Domain-Containing Protein 3 (LYPD3) in norepinephrine-treated MDA-MB-468 cells. Histology confirmed selective LYPD3 expression in primary and metastatic breast tumour samples. These findings demonstrate that basal-type cancer cells show a more aggressive adrenoceptor-β2-activated phenotype in the resting and stimulated state, which is attenuated by adrenoceptor-β2 inhibition. This study also highlights the first association between ADRβ2 signalling and LYPD3; its knockdown significantly reduced the basal and norepinephrine-induced activity of MCF-7 cells in vitro. The regulation of ADRβ2 signalling by LYPD3 and its metastasis promoting activities, reveal LYPD3 as a promising therapeutic target in the treatment of breast and other cancers.