1,126 research outputs found

    Ecological connectivity in Pacific deep-sea hydrothermal vent metacommunities

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    This work was supported by NSF grants OCE-0424953, OCE-1356738, and OCE-1829773 to L.S.M., NSF RAPID Grant OCE-1028862 to S.E.B., and Dalio Ocean Initiative and E/V Nautilus/Ocean Exploration Trust grant to S.E.B. and L.S.M. We acknowledge the sample collection permits CONAPESCA PPFE/DGOPA-010/17 and INEGI: Autorización EG0072017 associated to the Diplomatic Note number SRE 17-1087 (CTC/06727/17).Larval dispersal and connectivity between patchy, transient, deep-sea hydrothermal vent communities are important for persistence and recovery from disturbance. We investigated connectivity in vent metacommunities using the taxonomic similarity between larvae and adults to estimate the extent of exchange between communities and determine the relative roles of larval dispersal and environmental limitations (species sorting) in colonization. Connectivity at vent fields in 3 Pacific regions, Pescadero Basin, northern East Pacific Rise (EPR), and southern Mariana Trough, varied substantially and appeared to be driven by different processes. At Pescadero Basin, larval and adult taxa were similar, despite the existence of nearby (within 75 km) vent communities with different species composition, indicating limited larval transport and low connectivity. At EPR, larval and adult taxa differed significantly, despite the proximity of nearby vents with similar benthic composition, indicating substantial larval transport and potentially strong species sorting, but other factors may also explain these results. At the Mariana Trough, the larvae and adults differed significantly, indicating high larval transport but environmental limitations on colonization. We demonstrate that analysis of routinely collected samples and observations provides an informative indicator of metacommunity connectivity and insights into drivers of community assembly.Peer reviewe

    A transcriptome-driven analysis of epithelial brushings and bronchial biopsies to define asthma phenotypes in U-BIOPRED

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    RATIONALE AND OBJECTIVES: Asthma is a heterogeneous disease driven by diverse immunologic and inflammatory mechanisms. We used transcriptomic profiling of airway tissues to help define asthma phenotypes. METHODS: The transcriptome from bronchial biopsies and epithelial brushings of 107 moderate-to-severe asthmatics were annotated by gene-set variation analysis (GSVA) using 42 gene-signatures relevant to asthma, inflammation and immune function. Topological data analysis (TDA) of clinical and histological data was used to derive clusters and the nearest shrunken centroid algorithm used for signature refinement. RESULTS: 9 GSVA signatures expressed in bronchial biopsies and airway epithelial brushings distinguished two distinct asthma subtypes associated with high expression of T-helper type 2 (Th-2) cytokines and lack of corticosteroid response (Group 1 and Group 3). Group 1 had the highest submucosal eosinophils, high exhaled nitric oxide (FeNO) levels, exacerbation rates and oral corticosteroid (OCS) use whilst Group 3 patients showed the highest levels of sputum eosinophils and had a high BMI. In contrast, Group 2 and Group 4 patients had an 86% and 64% probability of having non-eosinophilic inflammation. Using machine-learning tools, we describe an inference scheme using the currently-available inflammatory biomarkers sputum eosinophilia and exhaled nitric oxide levels along with OCS use that could predict the subtypes of gene expression within bronchial biopsies and epithelial cells with good sensitivity and specificity. CONCLUSION: This analysis demonstrates the usefulness of a transcriptomic-driven approach to phenotyping that segments patients who may benefit the most from specific agents that target Th2-mediated inflammation and/or corticosteroid insensitivity

    Traction forces generated during studded boot‐surface interactions on third‐generation artificial turf: A novel mechanistic perspective

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    The traction forces generated during studded boot–surface interactions affect player performance and injury risk. Over 20 years of empirical research into traction on third generation (3G) artificial turf has met with only limited success in supporting the development of safer surfaces and boots. Thus, the purpose of this perspective article is to present a conceptual framework for generating scientific understanding on 3G turf traction through a novel mechanistic approach. A three-stage framework is proposed. Firstly, the hypothesized traction mechanisms and related analytical equations are identified, namely: friction between the boot outsole and surface; shear resistance of the performance infill layer to the outsole; and compressive resistance of the performance infill layer to horizontal stud displacement. Secondly, a Concept Map is generated to visually represent the contribution of the thirtynine variables identified as directly affecting the traction response. Finally, a Research Roadmap is constructed to guide the direction of future traction studies towards the development of safer surfaces and boots as well as improved mechanical tests to assess surface safety. The proposed framework represents the first attempt to deconstruct bootsurface interactions and hypothesize the science behind the mobilization of traction forces

    Identification of sVSG117 as an immunodiagnostic antigen and evaluation of a dual-antigen lateral flow test for the diagnosis of human african trypanosomiasis

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    The diagnosis of human African trypanosomiasis (HAT) caused by Trypanosoma brucei gambiense relies mainly on the Card Agglutination Test for Trypanosomiasis (CATT). There is no immunodiagnostic for HAT caused by T. b. rhodesiense. Our principle aim was to develop a prototype lateral flow test that might be an improvement on CATT.Pools of infection and control sera were screened against four different soluble form variant surface glycoproteins (sVSGs) by ELISA and one, sVSG117, showed particularly strong immunoreactivity to pooled infection sera. Using individual sera, sVSG117 was shown to be able to discriminate between T. b. gambiense infection and control sera by both ELISA and lateral flow test. The sVSG117 antigen was subsequently used with a previously described recombinant diagnostic antigen, rISG65, to create a dual-antigen lateral flow test prototype. The latter was used blind in a virtual field trial of 431 randomized infection and control sera from the WHO HAT Specimen Biobank.In the virtual field trial, using two positive antigen bands as the criterion for infection, the sVSG117 and rISG65 dual-antigen lateral flow test prototype showed a sensitivity of 97.3% (95% CI: 93.3 to 99.2) and a specificity of 83.3% (95% CI: 76.4 to 88.9) for the detection of T. b. gambiense infections. The device was not as good for detecting T. b. rhodesiense infections using two positive antigen bands as the criterion for infection, with a sensitivity of 58.9% (95% CI: 44.9 to 71.9) and specificity of 97.3% (95% CI: 90.7 to 99.7). However, using one or both positive antigen band(s) as the criterion for T. b. rhodesiense infection improved the sensitivity to 83.9% (95% CI: 71.7 to 92.4) with a specificity of 85.3% (95% CI: 75.3 to 92.4). These results encourage further development of the dual-antigen device for clinical use

    Surveillance recommendations based on an exploratory analysis of respiratory syncytial virus reports derived from the European Influenza Surveillance System

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    BACKGROUND: Respiratory syncytial virus (RSV) is an important pathogen that can cause severe illness in infants and young children. In this study, we assessed whether data on RSV collected by the European Influenza Surveillance Scheme (EISS) could be used to build an RSV surveillance system in Europe. METHODS: Influenza and RSV data for the 2002–2003 winter season were analysed for England, France, the Netherlands and Scotland. Data from sentinel physician networks and other sources, mainly hospitals, were collected. Respiratory specimens were tested for influenza and RSV mainly by virus culture and polymerase chain reaction amplification. RESULTS: Data on RSV were entered timely into the EISS database. RSV contributed noticeably to influenza-like illness: in England sentinel RSV detections were common in all age groups, but particularly in young children with 20 (40.8%) of the total number of sentinel swabs testing positive for RSV. Scotland and France also reported the highest percentages of RSV detections in the 0–4 year age group, respectively 10.3% (N = 29) and 12.2% (N = 426). In the Netherlands, RSV was detected in one person aged over 65 years. CONCLUSION: We recommend that respiratory specimens collected in influenza surveillance are also tested systematically for RSV and emphasize the use of both community derived data and data from hospitals for RSV surveillance. RSV data from the EISS have been entered in a timely manner and we consider that the EISS model can be used to develop an RSV surveillance system equivalent to the influenza surveillance in Europe

    Cost-Effectiveness of an Opportunistic Screening Programme and Brief Intervention for Excessive Alcohol Use in Primary Care

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    Effective prevention of excessive alcohol use has the potential to reduce the public burden of disease considerably. We investigated the cost-effectiveness of Screening and Brief Intervention (SBI) for excessive alcohol use in primary care in the Netherlands, which is targeted at early detection and treatment of ‘at-risk’ drinkers.We compared a SBI scenario (opportunistic screening and brief intervention for ‘at-risk’ drinkers) in general practices with the current practice scenario (no SBI) in the Netherlands. We used the RIVM Chronic Disease Model (CDM) to extrapolate from decreased alcohol consumption to effects on health care costs and Quality Adjusted Life Years (QALYs) gained. Probabilistic sensitivity analysis was employed to study the effect of uncertainty in the model parameters. In total, 56,000 QALYs were gained at an additional cost of €298,000,000 due to providing alcohol SBI in the target population, resulting in a cost-effectiveness ratio of €5,400 per QALY gained.Prevention of excessive alcohol use by implementing SBI for excessive alcohol use in primary care settings appears to be cost-effective

    Effectiveness of skills-based training using the Drink-less package to increase family practitioner confidence in intervening for alcohol use disorders

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    BACKGROUND: Misuse of alcohol is second only to tobacco as a leading cause of preventable death in Australia. There is an opportunity in family practice to detect problems and intervene with people at risk of alcohol-related harm before complications occur. However, family practitioners (FPs) report low levels of confidence in managing patients with drinking problems. The aim of this study was to determine whether the interactive training session using the 'Drink-less' package led to improvement in FPs' self-reported level of confidence in detecting and providing interventions for risky alcohol consumption. METHOD: FPs in urban and rural New South Wales were invited to training sessions in their local area. An introductory overview preceded a practical skills- based session, using the Drink-less package. Participants completed before and after evaluation forms. RESULTS: While 49% (CI 43 – 55) of the attending FPs indicated at baseline that they felt confident in identifying at-risk drinkers, this proportion rose to 90% (95% CI: 87 – 93) post-session, and they also reported increases in confidence from 36% (95% CI: 31 – 41) to 90% in their ability to advise patients. Urban FPs reported lower levels of confidence than rural FPs, both pre- and post-session. CONCLUSION: Training sessions in the Drink-less intervention resulted in increased self-reported confidence in detection and brief intervention for alcohol problems. Further research is needed to determine the duration of this effect and its influence on practice behaviour

    Conserved presence of G-quadruplex forming sequences in the Long Terminal Repeat Promoter of Lentiviruses

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    G-quadruplexes (G4s) are secondary structures of nucleic acids that epigenetically regulate cellular processes. In the human immunodeficiency lentivirus 1 (HIV-1), dynamic G4s are located in the unique viral LTR promoter. Folding of HIV-1 LTR G4s inhibits viral transcription; stabilization by G4 ligands intensifies this effect. Cellular proteins modulate viral transcription by inducing/unfolding LTR G4s. We here expanded our investigation on the presence of LTR G4s to all lentiviruses. G4s in the 5'-LTR U3 region were completely conserved in primate lentiviruses. A G4 was also present in a cattle-infecting lentivirus. All other non-primate lentiviruses displayed hints of less stable G4s. In primate lentiviruses, the possibility to fold into G4s was highly conserved among strains. LTR G4 sequences were very similar among phylogenetically related primate viruses, while they increasingly differed in viruses that diverged early from a common ancestor. A strong correlation between primate lentivirus LTR G4s and Sp1/NF\u3baB binding sites was found. All LTR G4s folded: their complexity was assessed by polymerase stop assay. Our data support a role of the lentiviruses 5'-LTR G4 region as control centre of viral transcription, where folding/unfolding of G4s and multiple recruitment of factors based on both sequence and structure may take place

    Characteristics of outdoor falls among older people: A qualitative study

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    Background Falls are a major threat to older people’s health and wellbeing. Approximately half of falls occur in outdoor environments but little is known about the circumstances in which they occur. We conducted a qualitative study to explore older people’s experiences of outdoor falls to develop understanding of how they may be prevented. Methods We conducted nine focus groups across the UK (England, Wales, and Scotland). Our sample was from urban and rural settings and different environmental landscapes. Participants were aged 65+ and had at least one outdoor fall in the past year. We analysed the data using framework and content analyses. Results Forty-four adults aged 65 – 92 took part and reported their experience of 88 outdoor falls. Outdoor falls occurred in a variety of contexts, though reports suggested the following scenarios may have been more frequent: when crossing a road, in a familiar area, when bystanders were around, and with an unreported or unknown attribution. Most frequently, falls resulted in either minor or moderate injury, feeling embarrassed at the time of the fall, and anxiety about falling again. Ten falls resulted in fracture, but no strong pattern emerged in regard to the contexts of these falls. Anxiety about falling again appeared more prevalent among those that fell in urban settings and who made more visits into their neighbourhood in a typical week. Conclusions This exploratory study has highlighted several aspects of the outdoor environment that may represent risk factors for outdoor falls and associated fear of falling. Health professionals are recommended to consider outdoor environments as well as the home setting when working to prevent falls and increase mobility among older people

    Seasonality and the effects of weather on Campylobacter infections

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    Background Campylobacteriosis is a major public health concern. The weather factors that influence spatial and seasonal distributions are not fully understood. Methods To investigate the impacts of temperature and rainfall on Campylobacter infections in England and Wales, cases of Campylobacter were linked to local temperature and rainfall at laboratory postcodes in the 30 days before the specimen date. Methods for investigation included a comparative conditional incidence, wavelet, clustering, and time series analyses. Results The increase of Campylobacter infections in the late spring was significantly linked to temperature two weeks before, with an increase in conditional incidence of 0.175 cases per 100,000 per week for weeks 17 to 24; the relationship to temperature was not linear. Generalized structural time series model revealed that changes in temperature accounted for 33.3% of the expected cases of Campylobacteriosis, with an indication of the direction and relevant temperature range. Wavelet analysis showed a strong annual cycle with additional harmonics at four and six months. Cluster analysis showed three clusters of seasonality with geographic similarities representing metropolitan, rural, and other areas. Conclusions The association of Campylobacteriosis with temperature is likely to be indirect. High-resolution spatial temporal linkage of weather parameters and cases is important in improving weather associations with infectious diseases. The primary driver of Campylobacter incidence remains to be determined; other avenues, such as insect contamination of chicken flocks through poor biosecurity should be explored
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