Automated seamless DNA co-transformation cloning with direct expression vectors applying positive or negative insert selection

<p>Abstract</p> <p>Background</p> <p>Molecular DNA cloning is crucial to many experiments and with the trend to higher throughput of modern approaches automated techniques are urgently required. We have established an automated, fast and flexible low-cost expression cloning approach requiring only vector and insert amplification by PCR and co-transformation of the products.</p> <p>Results</p> <p>Our vectors apply positive selection for the insert or negative selection against empty vector molecules and drive strong expression of target proteins in <it>E.coli </it>cells. Variable tags are available both in N-terminal or C-terminal position. A newly developed β-lactamase (ΔW290) selection cassette contains a segment inside the β-lactamase open reading frame encoding a stretch of hydrophilic amino acids that result in a T7 promoter when back-translated. This position of the promoter permits positive selection and attenuated expression of fusion proteins with C-terminal tags. We have tested eight vectors by inserting six target sequences of variable length, provenience and function. The target proteins were cloned, expressed and detected using an automated Tecan Freedom Evo II liquid handling work station. Only two colonies had to be picked to score with 85% correct inserts while 80% of those were positive in expression tests.</p> <p>Conclusions</p> <p>Our results establish co-transformation and positive/negative selection cloning in conjunction with the provided vectors and selection cassettes as an automatable alternative to commercialized high-throughput cloning systems like Gateway^®or ligase-independent cloning (LIC) <b/>.</p

The RESPECT study: a feasibility randomised controlled trial of a sexual health promotion intervention for people with serious mental illness in community mental health services in the UK

BackgroundPeople with serious mental illness (SMI) have sexual health needs but there is little evidence to inform effective interventions to address them. In fact, there are few studies that have addressed this topic for people with SMI outside USA and Brazil. Therefore, the aim of the study was to establish the acceptability and feasibility of a trial of a sexual health promotion intervention for people with SMI in the UK.MethodThe RESPECT study was a two-armed randomised controlled, open feasibility trial (RCT) comparing Sexual health promotion intervention (3 individual sessions of 1 h) (I) or treatment as usual (TAU) for adults aged 18 or over, with SMI, within community mental health services in four UK cities. The main outcome of interest was the percentage who consented to participate, and retained in each arm of the trial, retention for the intervention, and completeness of data collection. A nested qualitative study obtained the views of participants regarding the acceptability of the study using individual telephone interviews conducted by lived experience researchers.ResultsOf a target sample of 100, a total of 72 people were enrolled in the trial over 12 months. Recruitment in the initial months was low and so an extension was granted. However this extension meant that the later recruited participants would only be followed up to the 3 month point. There was good retention in the intervention and the study as a whole; 77.8% of those allocated to intervention (n = 28) received it. At three months, 81.9% (30 I; 29 TAU) and at 6 months, 76.3% (13 I and 16 TAU) completed the follow-up data collection. No adverse events were reported. There was good completeness of the data. The sexual health outcomes for the intervention group changed in favour of the intervention. Based on analysis of the qualitative interviews, the methods of recruitment, the quality of the participant information, the data collection, and the intervention were deemed to be acceptable to the participants (n = 22).ConclusionsThe target of 100 participants was not achieved within the study’s timescale. However, effective strategies were identified that improved recruitment in the final few months. Retention rates and completeness of data in both groups indicate that it is acceptable and feasible to undertake a study promoting sexual health for people with SMI. A fully powered RCT is required to establish effectiveness of the intervention in adoption of safer sex.Study registrationISRCTN Registry ISRCTN15747739 prospectively registered 5th July 2016

Concept, Design and Implementation of a Cardiovascular Gene-Centric 50 K SNP Array for Large-Scale Genomic Association Studies

A wealth of genetic associations for cardiovascular and metabolic phenotypes in humans has been accumulating over the last decade, in particular a large number of loci derived from recent genome wide association studies (GWAS). True complex disease-associated loci often exert modest effects, so their delineation currently requires integration of diverse phenotypic data from large studies to ensure robust meta-analyses. We have designed a gene-centric 50 K single nucleotide polymorphism (SNP) array to assess potentially relevant loci across a range of cardiovascular, metabolic and inflammatory syndromes. The array utilizes a “cosmopolitan” tagging approach to capture the genetic diversity across ∼2,000 loci in populations represented in the HapMap and SeattleSNPs projects. The array content is informed by GWAS of vascular and inflammatory disease, expression quantitative trait loci implicated in atherosclerosis, pathway based approaches and comprehensive literature searching. The custom flexibility of the array platform facilitated interrogation of loci at differing stringencies, according to a gene prioritization strategy that allows saturation of high priority loci with a greater density of markers than the existing GWAS tools, particularly in African HapMap samples. We also demonstrate that the IBC array can be used to complement GWAS, increasing coverage in high priority CVD-related loci across all major HapMap populations. DNA from over 200,000 extensively phenotyped individuals will be genotyped with this array with a significant portion of the generated data being released into the academic domain facilitating in silico replication attempts, analyses of rare variants and cross-cohort meta-analyses in diverse populations. These datasets will also facilitate more robust secondary analyses, such as explorations with alternative genetic models, epistasis and gene-environment interactions

Sexual health promotion in people with severe mental illness: the RESPECT feasibility RCT

BackgroundPeople with serious mental illness have sexual health needs, but there is limited evidence regarding effective interventions to promote their sexual health.ObjectivesTo develop a sexual health promotion intervention for people with serious mental illness, and to conduct a feasibility trial in order to establish the acceptability and parameters for a fully powered trial.DesignA two-armed randomised controlled, open feasibility study comparing usual care alone with usual care plus the adjunctive intervention.SettingFive community mental health providers in Leeds, Barnsley, Brighton and London.ParticipantsAdults aged ≥ 18 years with serious mental illness and receiving care from community mental health teams.InterventionsA remote, web-based computer randomisation system allocated participants to usual care plus the RESPECT (Randomised Evaluation of Sexual health Promotion Effectiveness informing Care and Treatment) intervention (three sessions of 1 hour) (intervention arm) or usual care only (control arm). The intervention was an interactive manualised package of exercises, quizzes and discussion topics focusing on knowledge, motivation and behavioural intentions to adopt safer sexual behaviours.Main outcome measuresFeasibility parameters including establishing the percentage of people who were eligible, consented and were retained in each arm of the trial, retention for the intervention, as well as the completeness of the data collection. Data were collected on knowledge, motivation to adopt safer sexual behaviour, sexual behaviour, sexual stigma, sexual health service use and quality of life. Data were collected at baseline and then at 3 months and 6 months post randomisation.ResultsOf a target of 100 participants, 72 people participated in the trial over 12 months. Of the 36 participants randomised to the intervention arm, 27 received some of the intervention (75.0%). At 3 months, 59 of the 72 participants completed follow-up questionnaires (81.9%) (30 participants from the intervention arm and 29 participants from the control arm). Only the first 38 participants were followed up at 6 months. However, data were collected on 29 out of 38 participants (76.3% retention): 13 in the intervention arm and 16 in the control arm. No adverse events were reported. Participant feedback confirmed that both the design and the intervention were acceptable. The economic analysis indicated high completion rates and completeness of data among participants who continued the trial.ConclusionsDespite the limitations, the findings suggest that it is both acceptable and feasible to undertake a sexual health promotion study for people with serious mental illness.Future workA fully powered randomised controlled trial would be required to establish the clinical effectiveness of the intervention.Trial registrationCurrent Controlled Trials ISRCTN15747739