Reassignment of the murine 3'TRDD1 recombination signal sequence.

T cell receptor genes are assembled in developing T lymphocytes from discrete V, D, and J genes by a site-specific somatic rearrangement mechanism. A flanking recombination signal, composed of a conserved heptamer and a semiconserved nonamer separated by 12 or 23 variable nucleotides, targets the activity of the rearrangement machinery to the adjoining V, D, and J genes. Following the rearrangement of V, D, or J genes, their respective recombination signals are ligated together. Although these signal joints are allegedly invariant, created by the head-to-head abuttal of the heptamers, some do exhibit junctional diversity. Recombination signals were initially identified by comparison and alignment of germ-line sequences with the sequence of rearranged genes. However, their overall low level of sequence conservation makes their characterization solely from sequence data difficult. Recently, computational analysis unraveled correlations between nucleotides at several positions scattered within the spacer and recombination activity, so that it is now possible to identify putative recombination signals and determine and predict their recombination efficiency. In this paper, we analyzed the variability introduced in signal joints generated after rearrangement of the TRDD1 and TRDD2 genes in murine thymocytes. The recurrent presence of identical nucleotides inserted in these signal joints led us to reconsider the location and sequence of the TRDD1 recombination signal. By combining molecular characterization and computational analysis, we show that the functional TRDD1 recombination signal is shifted inside the putative coding sequence of the TRDD1 gene and, consequently, that this gene is shorter than indicated in the databases

Stroke systems of care in high-income countries: what is optimal?

Stroke is a complex, time-sensitive, medical emergency that requires well functioning systems of care to optimise treatment and improve patient outcomes. Education and training campaigns are needed to improve both the recognition of stroke among the general public and the response of emergency medical services. Specialised stroke ambulances (mobile stroke units) have been piloted in many cities to speed up the diagnosis, triage, and emergency treatment of people with acute stroke symptoms. Hospital-based interdisciplinary stroke units remain the central feature of a modern stroke service. Many have now developed a role in the very early phase (hyperacute units) plus outreach for patients who return home (early supported discharge services). Different levels (comprehensive and primary) of stroke centre and telemedicine networks have been developed to coordinate the various service components with specialist investigations and interventions including rehabilitation. Major challenges include the harmonisation of resources for stroke across the whole patient journey (including the rapid, accurate triage of patients who require highly specialised treatment in comprehensive stroke centres) and the development of technology to improve communication across different parts of a service

Tipping the polaron–bipolaron balance : concentration and spin effects in doped oligo(aniline)s observed by UV-vis-NIR and TD-DFT

The oxidation states and doped forms of oligo(aniline)s are readily interconverted, and each state has characteristic UV-vis-NIR absorptions, making this spectroscopic technique ideal for in situ analysis of oligo(aniline) behaviour. However, experimental isolation of some of these states can be challenging and quantitative agreement between experimental and calculated spectra has been poor, making it difficult to identify the exact structure(s) and properties of each state. Here we report a comprehensive study of the UV-vis-NIR spectra of all oxidation states and doped forms of a series of oligo(aniline)s of varying lengths (dimer, tetramer and octamer), using a computationally inexpensive DFT method that is particularly suited to molecules with charge-transfer character. The computational study suggests that doped oligo(aniline)s form mixtures of spin isomers (polaronic and bipolaronic forms) in solution, and we have been able to evaluate and compare the most likely electronic configurations, as well as supporting our insights experimentally, by ESR spectroscopy. This doping approach enables tuning of the spin isomer equilibrium position by varying the concentration of protonic dopant, offering a new pathway to explore the electronic structure of π-conjugated molecules more generally, and opening up new approaches to the design of spintronic materials

Preventing Smoking in Young People: A Systematic Review of the Impact of Access Interventions

Aims: To examine existing evidence on the effectiveness of interventions that are designed to prevent the illegal sale of tobacco to young people. The review considers specific sub-questions related to the factors that might influence effectiveness, any differential effects for different sub-populations of youth, and barriers and facilitators to implementation. Methods: A review of studies on the impact of interventions on young people under the age of 18 was conducted. It included interventions that were designed to prevent the illegal sale of tobacco to children and young people. The review was conducted in July 2007, and included 20 papers on access restriction studies. The quality of the papers was assessed and the relevant data was extracted. Results: The evidence obtained from the review indicates that access restriction interventions may produce significant reductions in the rate of illegal tobacco sales to youth. However, lack of enforcement and the ability of youth to acquire cigarettes from social sources may undermine the effectiveness of these interventions. Conclusions: When access interventions are applied in a comprehensive manner, they can affect young people's access to tobacco. However, further research is required to examine the effects of access restriction interventions on young people's smoking behaviour

ABCA7 frameshift deletion associated with Alzheimer disease in African Americans

Objective: To identify a causative variant(s) that may contribute to Alzheimer disease (AD) in African Americans (AA) in the ATP-binding cassette, subfamily A (ABC1), member 7 (ABCA7) gene, a known risk factor for late-onset AD. Methods: Custom capture sequencing was performed on ∼150 kb encompassing ABCA7 in 40 AA cases and 37 AA controls carrying the AA risk allele (rs115550680). Association testing was performed for an ABCA7 deletion identified in large AA data sets (discovery n = 1,068; replication n = 1,749) and whole exome sequencing of Caribbean Hispanic (CH) AD families. Results: A 44-base pair deletion (rs142076058) was identified in all 77 risk genotype carriers, which shows that the deletion is in high linkage disequilibrium with the risk allele. The deletion was assessed in a large data set (531 cases and 527 controls) and, after adjustments for age, sex, and APOE status, was significantly associated with disease (p = 0.0002, odds ratio [OR] = 2.13 [95% confidence interval (CI): 1.42–3.20]). An independent data set replicated the association (447 cases and 880 controls, p = 0.0117, OR = 1.65 [95% CI: 1.12–2.44]), and joint analysis increased the significance (p = 1.414 × 10−5, OR = 1.81 [95% CI: 1.38–2.37]). The deletion is common in AA cases (15.2%) and AA controls (9.74%), but in only 0.12% of our non-Hispanic white cohort. Whole exome sequencing of multiplex, CH families identified the deletion cosegregating with disease in a large sibship. The deleted allele produces a stable, detectable RNA strand and is predicted to result in a frameshift mutation (p.Arg578Alafs) that could interfere with protein function. Conclusions: This common ABCA7 deletion could represent an ethnic-specific pathogenic alteration in AD

Understanding interactions in face-to-face and remote undergraduate science laboratories

This paper reviews the ways in which interactions have been studied, and the findings of such studies, in science education in both face-to-face and remote laboratories. Guided by a systematic selection process, 27 directly relevant articles were analysed based on three categories: the instruments used for measuring interactions, the research findings on student interactions, and the theoretical frameworks used in the studies of student interactions. In face-to-face laboratories, instruments for measuring interactions and the characterisation of the nature of interactions were prominent. For remote laboratories, the analysis of direct interactions was found to be lacking. Instead, studies of remote laboratories were mainly concerned with their practical scope. In addition, it is found that only a limited number of theoretical frameworks have been developed and applied in the research design. Existent theories are summarised and possible theoretical frameworks that may be implemented in studies of interactions in undergraduate laboratories are proposed. Finally, future directions for research on the interrelationship between student interactions and laboratory learning are suggested

Canadian Stroke Best Practice Recommendations: Hyperacute Stroke Care Guidelines, Update 2015

The 2015 update of the Canadian Stroke Best Practice Recommendations Hyperacute Stroke Care guideline highlights key elements involved in the initial assessment, stabilization, and treatment of patients with transient ischemic attack (TIA), ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and acute venous sinus thrombosis. The most notable change in this 5th edition is the addition of new recommendations for the use of endovascular therapy for patients with acute ischemic stroke and proximal intracranial arterial occlusion. This includes an overview of the infrastructure and resources required for stroke centers that will provide endovascular therapy as well as regional structures needed to ensure that all patients with acute ischemic stroke that are eligible for endovascular therapy will be able to access this newly approved therapy; recommendations for hyperacute brain and enhanced vascular imaging using computed tomography angiography and computed tomography perfusion; patient selection criteria based on the five trials of endovascular therapy published in early 2015, and performance metric targets for important time-points involved in endovascular therapy, including computed tomography-to-groin puncture and computed tomography-to-reperfusion times. Other updates in this guideline include recommendations for improved time efficiencies for all aspects of hyperacute stroke care with a movement toward a new median target door-toneedle time of 30 min, with the 90th percentile being 60 min. A stronger emphasis is placed on increasing public awareness of stroke with the recent launch of the Heart and Stroke Foundation of Canada FAST signs of stroke campaign; reinforcing the public need to seek immediate medical attention by calling 911; further engagement of paramedics in the prehospital phase with prehospital notification to the receiving emergency department, as well as the stroke team, including neuroradiology; updates to the triage and same-day assessment Conflict of interest: Leanne K. Casaubon: Medtronic (as an independent study patient assessor for a cardiac TAVI study); NoNO Inc. as site PI for the Frontier study of NA-1 neuroprotective in stroke; Covidien as an advisory board member. Jean-Martin Boulanger: conference speaker for BI Novartis, Sanofi Aventis, Merck, Merz, Allergan, Pfizer, Bayer, Boehringer Ingelheim. Gord Gubitz: speaker for Bayer, Boehringer Ingleheim, and BMS Pfizer. Dr. Michael D. Hill: Heart and Stroke Foundation of Alberta Board Chair, salary award holder; Vernalis Group Ltd and Merck Ltd Consultant; Hoffmann-LaRoche Canada, provided drug for clinical trial, consultancy and CME lecturer; Coviden, research grant holder; Servier Canada, CME lecturer (funds donated to charity); BMS Canada, consultancy (funds donated to charity); Alberta Innovates Health Solutions, program grant award; principal investigator, ESCAPE trial. Brian Moses: speaker for AstraZeneca, Bayer, Boehringer Ingelheim, Sanofi Aventis, and Servier; speaker and advisory board member for BMS, Eli Lilly, Merck, NovoNordisk, Pfizer; advisory board member for Medtronic. Funding: The development of the Canadian Stroke Best Practice Recommendations is funded in their entirety by the Heart and Stroke Foundation, Canada. No funds for the development of these guidelines come from commercial interests, including pharmaceutical and medical device companies. All members of the recommendation writing groups and external reviewers are volunteers and do not receive any remuneration for participation in guideline development, updates, and reviews. All participants complete a conflict of interest declaration prior to participation. of patients with transient ischemic attack; updates to blood pressure recommendations for the hyperacute phase of care for ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The goal of these recommendations and supporting materials is to improve efficiencies and minimize the absolute time lapse between stroke symptom onset and reperfusion therapy, which in turn leads to better outcomes and potentially shorter recovery times

Cartography of Methicillin-Resistant S. aureus Transcripts: Detection, Orientation and Temporal Expression during Growth Phase and Stress Conditions

BACKGROUND: Staphylococcus aureus is a versatile bacterial opportunist responsible for a wide spectrum of infections. The severity of these infections is highly variable and depends on multiple parameters including the genome content of the bacterium as well as the condition of the infected host. Clinically and epidemiologically, S. aureus shows a particular capacity to survive and adapt to drastic environmental changes including the presence of numerous antimicrobial agents. Mechanisms triggering this adaptation remain largely unknown despite important research efforts. Most studies evaluating gene content have so far neglected to analyze the so-called intergenic regions as well as potential antisense RNA molecules. PRINCIPAL FINDINGS: Using high-throughput sequencing technology, we performed an inventory of the whole transcriptome of S. aureus strain N315. In addition to the annotated transcription units, we identified more than 195 small transcribed regions, in the chromosome and the plasmid of S. aureus strain N315. The coding strand of each transcript was identified and structural analysis enabled classification of all discovered transcripts. RNA purified at four time-points during the growth phase of the bacterium allowed us to define the temporal expression of such transcripts. A selection of 26 transcripts of interest dispersed along the intergenic regions was assessed for expression changes in the presence of various stress conditions including pH, temperature, oxidative shocks and growth in a stringent medium. Most of these transcripts showed expression patterns specific for the defined stress conditions that we tested. CONCLUSIONS: These RNA molecules potentially represent important effectors of S. aureus adaptation and more generally could support some of the epidemiological characteristics of the bacterium

The effect of multiple adverse childhood experiences on health: a systematic review and meta-analysis

Background A growing body of research identifies the harmful effects that adverse childhood experiences (ACEs; occurring during childhood or adolescence; eg, child maltreatment or exposure to domestic violence) have on health throughout life. Studies have quantified such effects for individual ACEs. However, ACEs frequently co-occur and no synthesis of findings from studies measuring the effect of multiple ACE types has been done. Methods In this systematic review and meta-analysis, we searched five electronic databases for cross-sectional, case-control, or cohort studies published up to May 6, 2016, reporting risks of health outcomes, consisting of substance use, sexual health, mental health, weight and physical exercise, violence, and physical health status and conditions, associated with multiple ACEs. We selected articles that presented risk estimates for individuals with at least four ACEs compared with those with none for outcomes with sufficient data for meta-analysis (at least four populations). Included studies also focused on adults aged at least 18 years with a sample size of at least 100. We excluded studies based on high-risk or clinical populations. We extracted data from published reports. We calculated pooled odds ratios (ORs) using a random-effects model. Findings Of 11 621 references identified by the search, 37 included studies provided risk estimates for 23 outcomes, with a total of 253 719 participants. Individuals with at least four ACEs were at increased risk of all health outcomes compared with individuals with no ACEs. Associations were weak or modest for physical inactivity, overweight or obesity, and diabetes (ORs of less than two); moderate for smoking, heavy alcohol use, poor self-rated health, cancer, heart disease, and respiratory disease (ORs of two to three), strong for sexual risk taking, mental ill health, and problematic alcohol use (ORs of more than three to six), and strongest for problematic drug use and interpersonal and self-directed violence (ORs of more than seven). We identified considerable heterogeneity (I 2 of > 75%) between estimates for almost half of the outcomes. Interpretation To have multiple ACEs is a major risk factor for many health conditions. The outcomes most strongly associated with multiple ACEs represent ACE risks for the next generation (eg, violence, mental illness, and substance use). To sustain improvements in public health requires a shift in focus to include prevention of ACEs, resilience building, and ACE-informed service provision. The Sustainable Development Goals provide a global platform to reduce ACEs and their life-course effect on health. Funding Public Health Wales. © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licens

American Gut: an Open Platform for Citizen Science Microbiome Research

McDonald D, Hyde E, Debelius JW, et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3(3):e00031-18