39 research outputs found

    Correcting errors in synthetic DNA through consensus shuffling

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    Although efficient methods exist to assemble synthetic oligonucleotides into genes and genomes, these suffer from the presence of 1–3 random errors/kb of DNA. Here, we introduce a new method termed consensus shuffling and demonstrate its use to significantly reduce random errors in synthetic DNA. In this method, errors are revealed as mismatches by re-hybridization of the population. The DNA is fragmented, and mismatched fragments are removed upon binding to an immobilized mismatch binding protein (MutS). PCR assembly of the remaining fragments yields a new population of full-length sequences enriched for the consensus sequence of the input population. We show that two iterations of consensus shuffling improved a population of synthetic green fluorescent protein (GFPuv) clones from ∼60 to >90% fluorescent, and decreased errors 3.5- to 4.3-fold to final values of ∼1 error per 3500 bp. In addition, two iterations of consensus shuffling corrected a population of GFPuv clones where all members were non-functional, to a population where 82% of clones were fluorescent. Consensus shuffling should facilitate the rapid and accurate synthesis of long DNA sequences

    Rapid Publication Cyclosporin A Inhibits CD40 Ligand Expression in T Lymphocytes

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    Abstract The ligand for CD40 is expressed on activated T lymphocytes and delivers contact-dependen

    Social rearing environment influences dog behavioral development

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    Early life experiences are known to influence behavior later in life. In dogs, environmental influences of early home rearing could be exploited to improve the chances of developing adult behavior most suited to the adult environment. For working dog organizations, such as Guide Dogs, suitable adult behavior is important to ensure that dogs can fulfill their role as guides for people with visual impairment. Here, we test the hypothesis that dogs' home rearing environment will influence behavioral development. To investigate this hypothesis, carers of potential guide dogs (puppy walkers) completed a questionnaire, termed the Puppy Walker Questionnaire (PWQ), about the dog's behavior at 5, 8, and 12 months of age. An additional 11 questions were answered about the home environment at the last assessment. Because no questionnaire existed which measured behavior most relevant to Guide Dogs, questions from an existing questionnaire (Canine Behaviour and Research Questionnaire) were combined with additional questions. Thus, a subsidiary aim of the study was to test the reliability of the PWQ for measuring behavioral development of potential guide dogs. The PWQ, scored on a 100-mm visual analogue scale, grouped into 5 new scales: trainability, distractibility, general anxiety, body sensitivity, and stair anxiety, with 4 Canine Behaviour and Research Questionnaire scales: excitability, separation-related behavior, attachment and attention seeking, and energy level. For each reliable scale, multivariate linear regression identified significant predictors from the home environmental questions. The results suggest that home rearing environment is indeed important for behavioral development: 9 of 11 environmental variables were significant predictors of behavioral scores. Those environmental variables that appeared most important were social in nature. Dogs were scored as higher in energy level, excitability, and distractibility if they had been raised in a home with children, lower on energy level and distractibility the more experience of puppy walking their carer had, and lower on separation-related behavior the more they had been able to play with other dogs. These findings have implications for matching between dogs' early and later home environments. Follow-up of dogs in this study could help to elucidate effects on guiding suitability and matching between dog and guide dog owner

    An evidence-based decision assistance model for predicting training outcome in juvenile guide dogs

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    Working dog organisations, such as Guide Dogs, need to regularly assess the behaviour of the dogs they train. In this study we developed a questionnaire-style behaviour assessment completed by training supervisors of juvenile guide dogs aged 5, 8 and 12 months old (n = 1,401), and evaluated aspects of its reliability and validity. Specifically, internal reliability, temporal consistency, construct validity, predictive criterion validity (comparing against later training outcome) and concurrent criterion validity (comparing against a standardised behaviour test) were evaluated. Thirty-nine questions were sourced either from previously published literature or created to meet requirements identified via Guide Dogs staff surveys and staff feedback. Internal reliability analyses revealed seven reliable and interpretable trait scales named according to the questions within them as: Adaptability; Body Sensitivity; Distractibility; Excitability; General Anxiety; Trainability and Stair Anxiety. Intra-individual temporal consistency of the scale scores between 5±8, 8±12 and 5±12 months was high. All scales excepting Body Sensitivity showed some degree of concurrent criterion validity. Predictive criterion validity was supported for all seven scales, since associations were found with training outcome, at at-least one age. Thresholds of z-scores on the scales were identified that were able to distinguish later training outcome by identifying 8.4% of all dogs withdrawn for behaviour and 8.5% of all qualified dogs, with 84% and 85% specificity. The questionnaire assessment was reliable and could detect traits that are consistent within individuals over time, despite juvenile dogs undergoing development during the study period. By applying thresholds to scores produced from the questionnaire this assessment could prove to be a highly valuable decision-making tool for Guide Dogs. This is the first questionnaire-style assessment of juvenile dogs that has shown value in predicting the training outcome of individual working dogs

    Bathing Adaptations in the Homes of Older Adults (BATH-OUT-2) : study protocol for a randomised controlled trial, economic evaluation and process evaluation

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    Background The onset of disability in bathing is particularly important for older adults as it can be rapidly followed by disability in other daily activities; this may represent a judicious time point for intervention in order to improve health, well-being and associated quality of life. An important environmental and preventative intervention is housing adaptation, but there are often lengthy waiting times for statutory provision. In this randomised controlled trial (RCT), we aim to evaluate the effectiveness and cost-effectiveness of bathing adaptations compared to no adaptations and to explore the factors associated with routine and expedited implementation of bathing adaptations. Methods BATH-OUT-2 is a multicentre, two-arm, parallel-group RCT. Adults aged 60 and over who are referred to their local authority for an accessible level access shower will be randomised, using pairwise randomisation, 1:1, to receive either an expedited provision of an accessible shower via the local authority or a usual care control waiting list. Participants will be followed up for a maximum of 12 months and will receive up to four follow-ups in this duration. The primary outcome will be the participant’s physical well-being, assessed by the Physical Component Summary score of the Short Form-36 (SF-36), 4 weeks after the intervention group receives the accessible shower. The secondary outcomes include the Mental Component Summary score of the SF-36, self-reported falls, health and social care resource use, health-related quality of life (EQ-5D-5L), social care-related quality of life (Adult Social Care Outcomes Toolkit (ASCOT)), fear of falling (Short Falls Efficacy Scale), independence in bathing (Barthel Index bathing question), independence in daily activities (Barthel Index) and perceived difficulty in bathing (0–100 scale). A mixed-methods process evaluation will comprise interviews with stakeholders and a survey of local authorities with social care responsibilities in England. Discussion The BATH-OUT-2 trial is designed so that the findings will inform future decisions regarding the provision of bathing adaptations for older adults. This trial has the potential to highlight, and then reduce, health inequalities associated with waiting times for bathing adaptations and to influence policies for older adults. Trial registration ISRCTN Registry ISRCTN48563324. Prospectively registered on 09/04/2021

    Norovirus Regulation of the Innate Immune Response and Apoptosis Occurs via the Product of the Alternative Open Reading Frame 4

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    Small RNA viruses have evolved many mechanisms to increase the capacity of their short genomes. Here we describe the identification and characterization of a novel open reading frame (ORF4) encoded by the murine norovirus (MNV) subgenomic RNA, in an alternative reading frame overlapping the VP1 coding region. ORF4 is translated during virus infection and the resultant protein localizes predominantly to the mitochondria. Using reverse genetics we demonstrated that expression of ORF4 is not required for virus replication in tissue culture but its loss results in a fitness cost since viruses lacking the ability to express ORF4 restore expression upon repeated passage in tissue culture. Functional analysis indicated that the protein produced from ORF4 antagonizes the innate immune response to infection by delaying the upregulation of a number of cellular genes activated by the innate pathway, including IFN-Beta. Apoptosis in the RAW264.7 macrophage cell line was also increased during virus infection in the absence of ORF4 expression. In vivo analysis of the WT and mutant virus lacking the ability to express ORF4 demonstrated an important role for ORF4 expression in infection and virulence. STAT1-/- mice infected with a virus lacking the ability to express ORF4 showed a delay in the onset of clinical signs when compared to mice infected with WT virus. Quantitative PCR and histopathological analysis of samples from these infected mice demonstrated that infection with a virus not expressing ORF4 results in a delayed infection in this system. In light of these findings we propose the name virulence factor 1, VF1 for this protein. The identification of VF1 represents the first characterization of an alternative open reading frame protein for the calicivirus family. The immune regulatory function of the MNV VF1 protein provide important perspectives for future research into norovirus biology and pathogenesis

    The influence of viral RNA secondary structure on interactions with innate host cell defences

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    RNA viruses infecting vertebrates differ fundamentally in their ability to establish persistent infections with markedly different patterns of transmission, disease mechanisms and evolutionary relationships with their hosts. Although interactions with host innate and adaptive responses are complex and persistence mechanisms likely multi-factorial, we previously observed associations between bioinformatically predicted RNA secondary formation in genomes of positive-stranded RNA viruses with their in vivo fitness and persistence. To analyse this interactions functionally, we transfected fibroblasts with non-replicating, non-translated RNA transcripts from RNA viral genomes with differing degrees of genome-scale ordered RNA structure (GORS). Single-stranded RNA transcripts induced interferon-β mediated though RIG-I and PKR activation, the latter associated with rapid induction of antiviral stress granules. A striking inverse correlation was observed between induction of both cellular responses with transcript RNA structure formation that was independent of both nucleotide composition and sequence length. The consistent inability of cells to recognize RNA transcripts possessing GORS extended to downstream differences from unstructured transcripts in expression of TNF-α, other interferon-stimulated genes and induction of apoptosis. This functional association provides novel insights into interactions between virus and host early after infection and provides evidence for a novel mechanism for evading intrinsic and innate immune responses
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