Zoe Plummer

Post-genomics studies and their application to non-invasive prenatal diagnosis.

Non-invasive prenatal diagnosis (NIPD) offers the opportunity to eliminate completely the risky procedures of amniocentesis and chorionic villus sampling. The development of NIPD tests has largely centred around the isolation and analysis of fetal cells in the maternal circulation and the analysis of free fetal DNA in maternal plasma. Both of these techniques offer difficult technical challenges, and at the current moment in time the use of free fetal DNA is the simplest and most effective method of defining paternally inherited fetal genes for diagnosis. Post-genomics technologies that explore the proteins (proteomics) and transcripts (transcriptomics) released by the placenta into the maternal circulation offer new opportunities to identify genes and their protein products that are key diagnostic markers of disease (in particular Down syndrome), and might replace the current screening markers in use for prediction of risk of Down syndrome. In the ideal situation, these markers are sufficiently diagnostic not to require invasive sampling of fetal genetic material. Post-genomics techniques might also offer better opportunities for defining fetal cell-specific markers that might enhance their isolation from maternal blood samples. This review describes progress in these studies, particularly those funded by the Special Non-invasive Advances in Fetal and Neonatal Evaluation (SAFE) Network of Excellence.

4.1R-deficient human red blood cells have altered phosphatidylserine exposure pathways and are deficient in CD44 and CD47 glycoproteins

Phosphatidylserine exposure on the surface of the red cell membrane initiates the process of eryptosis, the red cell death program. The 4.1R protein is a phosphatidylserine binding protein. In this article, the authors demonstrate that erythrocytes from two patients with 4.1R deficiency show alterations of other proteins of the 4.1 multicomplex such as CD44 and CD47 and significantly increased phosphatidylserine exposure, suggesting a role for 4.1 protein in a signaling pathway relevant for red cell turnover. Background Protein 4.1R is an important component of the red cell membrane skeleton. It imparts structural integrity and has transmembrane signaling roles by direct interactions with transmembrane proteins and other membrane skeletal components, notably p55 and calmodulin. Design and Methods Spontaneous and ligation-induced phosphatidylserine exposure on erythrocytes from two patients with 4.1R deficiency were studied, using CD47 glycoprotein and glycophorin C as ligands. We also looked for protein abnormalities in the 4.1R - based multiprotein complex. Results Phosphatidylserine exposure was significantly increased in 4.1R-deficient erythrocytes obtained from the two different individuals when ligands to CD47 glycoprotein were bound. Spontaneous phosphatidylserine exposure was normal. 4.1R, glycophorin C and p55 were missing or sharply reduced. Furthermore there was an alteration or deficiency of CD47 glycoprotein and a lack of CD44 glycoprotein. Based on a recent study in 4.1R-deficient mice, we found that there are clear functional differences between interactions of human red cell 4.1R and its murine counterpart. Conclusions Glycophorin C is known to bind 4.1R, and we have defined previously that it also binds CD47. From our evidence, we suggest that 4.1R plays a role in the phosphatidylserine exposure signaling pathway that is of fundamental importance in red cell turnover. The linkage of CD44 to 4.1R may be relevant to this process.

Propofol cardioplegia: A single-center, placebo-controlled, randomized controlled trial

OBJECTIVES Cardiac surgery with cardiopulmonary bypass and cardioplegic arrest is an effective treatment for coronary artery and aortic valve diseases. However, the myocardium sustains reperfusion injury after ischemic cardioplegic arrest. Our objective was to assess the benefits of supplementing cardioplegia solution with the general anesthetic propofol in patients undergoing either coronary artery bypass grafting (CABG) or aortic valve replacement (AVR). METHODS A single-center, double-blind randomized controlled trial was carried out to compare cardioplegia solution supplemented with propofol (concentration 6 μg/mL) versus intralipid (placebo). The primary outcome was cardiac troponin T release over the first 48 hours after surgery. RESULTS We recruited 101 participants (51 in the propofol group, 50 in the intralipid group); 61 underwent CABG and 40 underwent AVR. All participants were followed to 3 months. Cardiac troponin T release was on average 15% lower with propofol supplementation (geometric mean ratio, 0.85; 95% confidence interval [CI], 0.73-1.01; P = .051). There were no differences for CABG participants but propofol-supplemented participants undergoing AVR had poorer postoperative renal function (geometric mean ratio, 1.071; 95% CI, 1.019-1.125; P = .007), with a trend toward longer intensive care stay (median, 89.5 vs 47.0 hours; hazard ratio, 0.58; 95% CI, 0.31-1.09; P = .09) and fewer with perfect health (based on the EQ-5D health utility index) at 3 months (odds ratio, 0.26; 95% CI, 0.06-1.05; P = .058) compared with the intralipid group. Safety profiles were similar. There were no deaths. CONCLUSIONS Propofol supplementation in cardioplegia appears to be cardioprotective. Its influence on early clinical outcomes may differ between CABG and AVR surgery. A larger, multicenter study is needed to confirm or refute these suggestions.

The Effects of Propofol Cardioplegia on Blood and Myocardial Biomarkers of Stress and Injury in Patients With Isolated Coronary Artery Bypass Grafting or Aortic Valve Replacement Using Cardiopulmonary Bypass: Protocol for a Single-Center Randomized Controlled Trial

Background Despite improved myocardial protection strategies, cardioplegic arrest and ischemia still result in reperfusion injury. We have previously published a study describing the effects of propofol (an anesthetic agent commonly used in cardiac surgery) on metabolic stress, cardiac function, and injury in a clinically relevant animal model. We concluded that cardioplegia supplementation with propofol at a concentration relevant to the human clinical setting resulted in improved hemodynamic function, reduced oxidative stress, and reduced reperfusion injury when compared to standard cardioplegia. Objective The Propofol cardioplegia for Myocardial Protection Trial (ProMPT) aims to translate the successful animal intervention to the human clinical setting. We aim to test the hypothesis that supplementation of the cardioplegic solution with propofol will be cardioprotective for patients undergoing isolated coronary artery bypass graft or aortic valve replacement surgery with cardiopulmonary bypass. Methods The trial is a single-center, placebo-controlled, randomized trial with blinding of participants, health care staff, and the research team. Patients aged between 18 and 80 years undergoing nonemergency isolated coronary artery bypass graft or aortic valve replacement surgery with cardiopulmonary bypass at the Bristol Heart Institute are being invited to participate. Participants are randomly assigned in a 1:1 ratio to either cardioplegia supplementation with propofol (intervention) or cardioplegia supplementation with intralipid (placebo) using a secure, concealed, Internet-based randomization system. Randomization is stratified by operation type and minimized by diabetes mellitus status. Biomarkers of cardiac injury and metabolism are being assessed to investigate any cardioprotection conferred. The primary outcome is myocardial injury, studied by measuring myocardial troponin T. The trial is designed to test hypotheses about the superiority of the intervention within each surgical stratum. The sample size of 96 participants has been chosen to achieve 80% power to detect standardized differences of 0.5 at a significance level of 5% (2-tailed) assuming equal numbers in each surgical stratum. Results A total of 96 patients have been successfully recruited over a 2-year period. Results are to be published in late 2014. Conclusions Designing a practicable method for delivering a potentially protective dose of propofol to the heart during cardiac surgery was challenging. If our approach confirms the potential of propofol to reduce damage during cardiac surgery, we plan to design a larger multicenter trial to detect differences in clinical outcomes. Trial Registration International Standard Randomized Controlled Trial Number (ISRCTN): 84968882; http://www.controlled-trials.com/ISRCTN84968882/ProMPT (Archived by WebCite at http://www.webcitation.org/6Qi8A51BS).

Protocol for a randomised controlled trial for Reducing Arthritis Fatigue by clinical Teams (RAFT) using cognitive–behavioural approaches

Introduction Rheumatoid arthritis (RA) fatigue is distressing, leading to unmanageable physical and cognitive exhaustion impacting on health, leisure and work. Group cognitive–behavioural (CB) therapy delivered by a clinical psychologist demonstrated large improvements in fatigue impact. However, few rheumatology teams include a clinical psychologist, therefore, this study aims to examine whether conventional rheumatology teams can reproduce similar results, potentially widening intervention availability. Methods and analysis This is a multicentre, randomised, controlled trial of a group CB intervention for RA fatigue self-management, delivered by local rheumatology clinical teams. 7 centres will each recruit 4 consecutive cohorts of 10–16 patients with RA (fatigue severity ≥6/10). After consenting, patients will have baseline assessments, then usual care (fatigue self-management booklet, discussed for 5–6 min), then be randomised into control (no action) or intervention arms. The intervention, Reducing Arthritis Fatigue by clinical Teams (RAFT) will be cofacilitated by two local rheumatology clinicians (eg, nurse/occupational therapist), who will have had brief training in CB approaches, a RAFT manual and materials, and delivered an observed practice course. Groups of 5–8 patients will attend 6×2 h sessions (weeks 1–6) and a 1 hr consolidation session (week 14) addressing different self-management topics and behaviours. The primary outcome is fatigue impact (26 weeks); secondary outcomes are fatigue severity, coping and multidimensional impact, quality of life, clinical and mood status (to week 104). Statistical and health economic analyses will follow a predetermined plan to establish whether the intervention is clinically and cost-effective. Effects of teaching CB skills to clinicians will be evaluated qualitatively. Ethics and dissemination Approval was given by an NHS Research Ethics Committee, and participants will provide written informed consent. The copyrighted RAFT package will be freely available. Findings will be submitted to the National Institute for Health and Care Excellence, Clinical Commissioning Groups and all UK rheumatology departments. Trial registration number ISRCTN: 52709998; Protocol v3 09.02.2015.

Near-patient coagulation testing to predict bleeding after cardiac surgery: a cohort study

Essentials Near‐patient testing improves coagulopathy diagnosis in cardiac surgery patients with severe bleeding. We investigated how well pre‐emptive near‐patient testing predicted severe bleeding. Severe bleeding could be predicted using both near‐patient tests and patient clinical characteristics. Near‐patient test results gave little additional predictive value over clinical characteristics alone.

AB1130-HPR Cognitive Therapy for Reducing The Impact of Rheumatoid Arthritis Fatigue: Sucessful Strategies for Meeting Targets in A Complex Health Care Intervention

Background Complex interventions are widely used in modern health care practice and are defined as those having potentially interacting components. Evaluation can be challenging due to difficulties in logistics, standardisation, delivery, recruiting to time and target (particularly in multi-centre studies) and minimising attrition and data loss. We report how the RAFT study (a 7-centre randomised controlled trial comparing a complex, group cognitive-behavioural intervention with standard care, for the reduction of fatigue impact in patients with rheumatoid arthritis) is implementing successful strategies to meet targets. The study requires patients to make a substantial commitment over a two year period and for the intervention to be delivered by routine clinical staff trained for this purpose. Objectives To recruit to time and target, ensure intervention delivery, minimise attrition and maximise retention. Methods Maximising recruitment: Funded research nurse time at all 7 sites, mailshot approach option, recruitment posters, flexible/pragmatic approach to session attendance, telephone, email and postal contact, newsletter and regular knowledge exchange between the central management team and sites, weekly recruitment review. Ensuring intervention delivery: Flexible course dates and times, regular discussions around foreseeable issues and preventative actions, provision of real-time clinical supervision and full-time telephone/email support. Minimising attrition and data loss: Primary outcome collected by telephone ensuring regular personal contact. Secondary data collected by postal questionnaire reducing the number of hospital visits. Telephone reminders, partial withdrawal options, personalised letters and thank you cards. Patient involvement: Acceptability and feasibility consultations with our 2 patient partners. Both have experience of attending the intervention, were co-applicants on the grant proposal and continue to provide the patient perspective as members of the trial management group. Results Recruitment: Target of 300 participants with no recent medication changes and a fatigue level of ≥6 (on a 1–10 scale where 10 is totally exhausted). During the 2 year recruitment phase 333 participants were randomised (11% over target). Intervention delivery: 28/28 programmes successfully delivered with 7/7 sites and 14/15 tutors remaining fully engaged with the study. Attrition and data loss: Retention at 6 months is currently 92.5% (sample size allows for 20% attrition). Data returned by those reaching the 6 month time point is 100% for the primary outcome and 97% for secondary outcomes. Conclusions Advanced planning and consistent application of these strategies has ensured success so far. A flexible and pragmatic approach, regular communication between local and central teams, personal contact with participants and extensive patient partner input are key components. Acknowledgement This work is funded by the NIHR HTA commissioned call [project number 11/112/01] Disclosure of Interest None declared

Challenges of recruiting elderly patients undergoing cardiac surgery - our experience of recruiting 2500 participants in just 30 months at a single centre

Background Emergency operations, cancellations, changing operating theatre schedules, day of surgery arrivals and an aging population are all challenges facing the recruitment of cardiac surgery patients into studies. The observational Coagulation and Platelet Function Testing in Cardiac Surgery (COPTIC) study, which required patients to consent to give blood samples at the start and end of surgery, is the largest of its kind and the largest single study conducted at our hospital. We describe our experience of recruitment and retention and share our successful strategy.