Search

The organization of intracellular space into distinct, membraneless, compartments is a ubiquitous feature of living organisms. It has recently become apparent that many of these biomolecular condensates may be formed by liquid-liquid phase separation. Representing (liquid-like) regions enriched in specific proteins and nucleic acid species, they partition biomolecules by providing a chemical environment distinct from the surrounding intracellular milieu. Regulation of their interfacial phenomena allows cells to localise them to specific regions of intracellular space, as well as control the kinetics of their formation and growth. Through identifying and studying constituent proteins of biomolecular condensates, researchers have deciphered many of the sequence features necessary for phase separation. Of principal importance was the development of model biomolecular condensate systems in vitro. This has enabled rigourous physical modelling in a controlled environment, allowing investigations into the molecular specifics driving condensate formation through phase separation. In this thesis, we advance the study of biomolecular condensates, basing our research around the Ddx4N model system focusing on condensate formation and interfacial phenomena. Ddx4N is the intrinsically disordered N-terminal tail of human ATP-dependent DEADbox RNA helicase 4, shown to be necessary and sufficient for phase separation in vitro and in cells. Since its discovery as a condensate forming protein, its sequence features have been identified in numerous other condensate associated proteins, making Ddx4N an ideal model system. First, we expand current knowledge concerning its phase separation. By investigating mutant sequences in vitro, the the role of protein net charge is revealed, whilst also emphasising the effect of phenylalanine/tyrosine on cation-π interactions. Furthermore, we show the effect of net charge is reproducible in a cellular environment, using in cell fluorescence images of exogenous Ddx4N condensates. Our attention is then drawn to the development of an experimental pipeline affording the precise characterisation of in vitro condensate interfacial phenomena through drop shape analysis. Confocal microscopy, the Young-Laplace equation and bespoke image analysis are combined to allow measurement of capillary lengths and contact angles of condensates resting on solid surfaces. Measuring condensate contact angles using our automated technique is found to be superior to a recently reported manual method. We then focus on the fluid-fluid interfacial tension of condensates, presenting calculations based around the theory of van der Waals, implemented through the work of Scheutjens and Fleer. Then we aimed to verify these calculations by measuring condensate capillary lengths through drop shape analysis, with a view to extracting their fluid-fluid interfacial tensions. However, we saw an unexpected increase of capillary length with condensate size. After close interrogation of the experimental technique and possible physical origins, we were unable to and an explanation for this phenomena. As such, the origin of our observed positive relationship between capillary length and condensate size remains an open question, requiring further study. Finally, motivated by the observation that membrane-associated condensates are localised through specific interactions with membrane bound species, we decided to investigate the non-specific wetting of membrane surfaces by biomolecular condensates. Through measurement of contact angles on a supported lipid bilayer, we found condensates to be repelled by the membrane. Further measurements of condensate contact angles on hydrophilic and hydrophobic glass surfaces revealed a role for hydrophobic interactions, likely serving to repel condensates from necessarily hydrophilic headgroups of lipid bilayers. These data suggest repulsion between biomolecular condensates and membranes is responsible for the maintenance of endogenous condensates in the cytoplasm/nucleoplasm, away from intracellular membranes. Furthermore, we discover a positive line tension at the three phase contact line, with a deleterious impact on condensate wetting at the micrometer lengthscale.

Background Cystic Fibrosis (CF) is a genetic condition affecting approximately 200 children and young people in Northern Ireland. A diagnosis of CF is life-changing for patients and their families. At diagnosis they are provided with a wealth of educational information. This can often be overwhelming at what is already a particularly challenging time. Consequently the CF team were keen to develop a resource which would enable patients and their families to access reliable educational information in their own time which would be of benefit both at the time of diagnosis and as they grew older. Methods We decided to create an app which could be downloaded and accessed free of charge. During the design process we consulted with medical professionals, CF specialist nurses, dieticians, physiotherapists, pharmacists, clinical psychologists and social workers in addition to patients and their families. Results We created an app containing information about the local adult and paediatric CF services and providing links to useful online resources in addition to material on physiotherapy, dietetics, medications, common infections, evolving research and the transition process. The app was made available to patients in 2018. To date it has been accessed over 3,200 times. Verbal feedback has been very positive. It costs approximately £75 per year to publish online and is updated regularly by members of the multidisciplinary team. Conclusions The app has already proved a useful resource for patients and their families. We are keen to continue to develop this resource by formally evaluating and adjusting the content accordingly., Background and Aims Type 1 diabetes requires significant self-management. Teenagers have motivation but are also vulnerable. The Flash Glucose monitoring system is a device that measures interstitial glucose level by scanning the sensor placed upon the arm. Does flash glucose monitoring improve the HBA1c and overall satisfaction in 12-16 year old patients with type 1 diabetes with suboptimal levels? Methods Flash glucose monitoring was made available to all patients with type 1 diabetes who fulfilled set criteria and after completing a training session. We included 12-16 year olds with hba1c 69 mmol/mol (8.5%) and above. Demographic details were recorded. We monitored their HbA1c at 3 and 6 months from starting flash glucose monitoring. We also asked them 2 questions - Do you feel the flash glucose monitoring system has made it easier for you to manage your diabetes on a day to day basis - Do you think it will improve your overall HbA1c level? Results 24 patients aged 12-16 years had Hba1c above 69mmol/mol 8 were eliminated either due to recent diagnosis of type 1 diabetes (3) or refusal to use Libre (5) therefore N=16. Median: HbA1c before starting Libre= 78mmol/mol (mean=85), at 3 months 86 mmol/mol ( mean=85) and 6 months 73mmol/mol ( mean 73) p=0.016 At 3 months all felt Libre made it easier to manage day to day sugar levels Conclusion There was a significant fall in Hba1c (P=0.016) 6 months after using Flash Glucose monitoring. Most felt it improved overall satisfaction, Background and Aims In the SHSCT diabetes team, our goal is to empower our young people and encourage selfmanagement of their diabetes. A key component of this is to understand the expectations of young people attending our clinics, and therefore provide patient centred consultations. Our aim was to identify each patient’s goals and specific areas for discussion when attending clinic. Methods We distributed questionnaires, the in form of a ‘mind bubble’, to young people over 12 years attending paediatric diabetes clinics in the Southern Trust over a two month period. A ‘mind bubble’ is a simplified visual questionnaire designed to be user-friendly and engage with young people. Young people were asked ‘What would you like to discuss today at your diabetes clinic?’ and their responses were then addressed at that attendance. Results We received 32 completed ‘mind bubbles’. The most common response was for advice on hyper- and hypoglycaemia (44%). 7 responses (22%) were regarding practical advice on holidays and exercise, 6 responses (19%) for specific questions regarding insulin pumps and infusion sets, and 3 (9%) regarding the use of associated computer programmes. 3 responses (9%) asked for education on ketones. Conclusions The ‘mind bubble’ provides a practical way for young people to inform the diabetes team of their expectations for each clinic visit. The wide variety of responses highlights the challenges of engaging with young people with complex, life long conditions, and the need for patient centred care to enable our young people grow in confidence., BACKGROUND Nursing handovers represent the transfer of professional responsibility for patient care between team members. Patient safety depends on clear and accurate handovers. Staff surveys in 2014 identified dissatisfaction with previous handover practice. Verbal handovers occurred away from the patient bedside, without use of standardised communication tools. An opportunity to improve nursing handovers was identified. AIMS To achieve 90% compliance of Bedside Nursing Handovers. To improve staff, patient and parent satisfaction. To create a culture of handover practice which prioritises patient safety METHODS A literature search was performed to identify best practice. Staff feedback exercises and “brainstorming” allowed evidence based interventions to be tailored to address specific shortcomings. Plan-Do-Study-Act cycles focused on: Face-to-face education/staff training SBAR communication tool implementation Introduction of written handover proformas Improving start and end times (minimising interruptions) Improving accuracy of patient information transfer Utilisation of the Patient Safety Scan (safety checklist) -Regular audits monitored compliance. Results were displayed on a noticeboard for staff to identify areas for improvement and celebrate success. RESULTS Bedside handovers have increased from 0% to 100%. Parents and patients listen to handovers and have an opportunity to contribute. All handovers utilise SBAR communication and patient safety checks (namebands, PEWS charts, fluid balances, airway equipment and medications). Staff and parental feedback has demonstrated increased satisfaction and confidence with this safer, holistic, patient-centred handover. CONCLUSIONS Nursing bedside handovers have become routine practice in Maynard- Sinclair Ward and staff, patient and parental feedback continues to be extremely positive., Background & Aims In the paediatric patient, weight is required to calculate drug dosages and fluid prescriptions. In some instances, an actual weight measurement is not possible or practical and an estimate must be made. This study aimed to compare the accuracy of weight estimation using the current versus previous APLS formulae in Northern Irish children. Methods The actual weight and age of patients was collected from patient records from children attending the RBHSC Paediatric Emergency Department in April 2016 (n=523). The estimated weight using current and previous APLS formulae was calculated for each subject and compared to actual weight using the mean residual sum of squares (RSS). A sub-analysis of age groups was conducted (1-11 months; 1-5 years; 6-12 years; 13+ years). Results The Mean RSS across all age groups was 46.75 for the current formulae versus 103.23 for the previous formula. The comparative Mean RSS (current:previous formulae) for specified age groups was as follows: (1-11 months 1.65:4.88 n=82; 1-5 years 10.29:10.29 n=231; 6-12 years 77.85:181.12 n=185 ; 13+ years 301.40:708.13 n=25). Conclusion The current APLS formula is overall more accurate than the previous APLS formula at estimating weight in children and across almost all age groups (note: the formulae for 1-5 year olds were equivalent). Weight estimates are less accurate in older children with both calculation methods., Background & Aims Most studies explore children and young people’s (CYP’s) experience of healthcare without consulting CYP directly. The aim of this study is to explore “what is known about children and young people’s experiences of receiving healthcare from their present perspective?” Methods Scoping review methodology was used to address the research question through a phenomenological lens of direct quotation. Basic numerical analysis and qualitative content analysis was completed. Results 3095 CYP, aged 0-18 years, participated in the 89 studies included in this literature review at an international level. Studies describing CYPHCEs through direct quotations have increased from 2005. Most studies used semi-structured participatory interviews. CYPHCEs are complex and unique to that individual. Twelve themes emerged. Communication and autonomy were the most common themes. CYP are asking for better communication at an understandable level. Conclusions CYP have an increasingly active voice in qualitative healthcare research at an international level. A lack of patient-specific communication, which acknowledges the patient’s ability to understand, has a negative impact on CYPHCEs. CYP’s participation in their own care affects their experience, however, the level of participation each seeks is varies., Background and aims Fit Families for the Future launched in May 2019 and is presently Northern Ireland’s only multidisciplinary service for children (4-16 years) with BMI > 98th centile. Over 12 months we aim to support 48 children to achieve a healthier BMI. Methods Children are referred by paediatricians, GPs and school nurses. Each family is invited to clinic for holistic assessment by a paediatrician, physiotherapist, associate psychologist and dietician. Outcome measures include BMI, 6-minute walk test, grip strength, blood pressure testing, dietary history and quality-of-life measures. Parents are encouraged to have their own weight/BMI checked. An individualised family plan is coproduced. Treatments include a series of educational evening classes and/or oneto-one input from dietetics/physiotherapy/health coaching. Outcome measures will be reassessed at 3, 6 and 12 months. Results Currently 30 children have attended Fit Families assessment clinics. 29 are in the treatment phase. 1 child discharged as 12kg. One child’s BMI increased, and another’s remained static. Family and staff feedback have been overwhelmingly positive. Conclusions In response to feedback we have extended our evening class programme to 6-weeks, introduced text reminders for appointments and strengthened our outreach programme with community organisations including Parkrun and local councils. We are excited to recruit more families, see more results from the programme and develop a viable business case for this gap in paediatric services., Background and Aims Medication administration errors (MAE) are a common problem. To address this problem it is important to understand the how and why MAEs occur. The study aims to investigate; ° Type and characteristics of MAE; ° Underlying factors that led to these errors. Methods A mixed methods study of clinical incident reports related to MAE was undertaken. MAEs involving children 0-16 years, in paediatric medical and surgical wards in Northern Ireland (NI) between 2011- 2015 were included. The characteristics and types of MAE were quantified, then MAE descriptions were thematically analysed t determine the underlying contributing factors which led to error. Results In total 369 incident reports of MAEs (including 391 drugs) were analysed. The most common: MAE type was omitted and delayed (n=103; 28%). The most common drug class was antimicrobials (n=93; 24). MAE characteristics include; children 5 years and under (n=178; 48%); insignificant harm (n=257; 70%); Contributing themes were related to management and organisational processes; features of the team, environment, task, and patient; and unsafe acts of staff. Defences were also found but commonly occurred after MAEs reached the patient. Conclusion This research has found there are multiple types, characteristics and contributing factors associated with MAE. The findings should be used to target specific error types, drug classes and contributing factors to prevent potential MAEs in future practice., BACKGROUND White coats to lanyards, did we solve the infection control risk problem? Lanyards serve as a quick method of identifying the position of staff. However, with infection control becoming a prominent clinical priority, we are washing our hands but are we washing our lanyards? By exploring hygiene practices with regards to lanyards we can assess whether there is a need for change in the responsibility we take for what hangs around our neck. AIM To assess the lanyard hygiene practices of healthcare professionals within a district general hospital. METHOD A mixed-method survey of healthcare staff with dichotomous, nominal and free-text responses which were analysed numerically and thematically. RESULTS This questionnaire provided information on potential gaps relating to appropriate lanyard infection control measures. Common themes demonstrated that the majority of lanyards were not washed nor replaced regularly, despite being worn continuously throughout the day, including travel to and from work. Gaps in staff adherence and understanding of adequate lanyard hygiene were evident. CONCLUSION The survey reiterated the need for clear information and guidance with regards to lanyard hygiene practices. The data collected raises awareness of the current discontinuity in attention and supply of adequate information in order to empower staff to take responsibility for their neck-suspended lanyard. The implementation of a lanyard hygiene protocol and consideration of future movement towards rubberised lanyards are practical measures that could improve upon infection control standards within hospitals., Background & Aims Some people choose not to vaccinate their children resulting at least in part to a rise in the incidence of vaccine preventable disease such as measles globally. Interactions between Health Care Professionals (HCP) and parents help to alleviate vaccination concerns. What is the prevalence and cause of vaccine hesitancy or refusal in mothers attending antenatal clinics in a District General Hospital? Can targeted intervention strategies such as group educational sessions improve confidence in vaccine safety? Can educational sessions delivered to HCP about ‘vaccine safety & having conversations with vaccine hesitant families’ improve their confidence to undertake these discussions? Methods 147 consecutive mothers attending antenatal clinics filled questionnaires. Data including prevalence and spectrum of vaccine hesitancy with causation was obtained and analysed. Bespoke information sharing sessions on vaccine safety and having conversations with vaccine hesitant parents were delivered by trained HCP to families and HCP respectively. Feedback was analysed Results Majority of mothers had no concerns about vaccinating their baby (86%)with commonest concerns being ‘side effects like fever and allergic response’ followed by ‘link between MMR and autism’ 2 ‘Vaccine safety’ sessions for families significantly increased their confidence in vaccine safety (p=0.0004) 4 ‘Vaccine safety & having conversation’ sessions attended by multidisciplinary HCP significantly increased their confidence in the above area (p=0.001) Conclusions Majority of families are confident about the safety and efficiency of vaccines. Education and vaccine safety sessions targeted towards families and HCP both increase the confidence in vaccine safety., Fragile X Syndrome (FXS) is often described as the most common cause of intellectual disability (ID) in males. Anecdotally, we have noted a low diagnostic yield from FXS testing. FXS is typically caused by a triplet repeat expansion (>200 CGGs) in FMR1. FXS more commonly affects males, however it is estimated that one third of females are symptomatic. Classical features of FXS include ID, autism, behavioural disturbance and dysmorphism. Smaller expansions in FMR1 (pre-mutations) are associated with Fragile XAssociated Tremor/Ataxia Syndrome (FXTAS) and Premature Ovarian Insufficiency (POI). We retrospectively reviewed the results of FMR1 assays undertaken at the NIRGC between 24/05/12 – 08/07/19. In total, 521 FMR1 assays were performed for a variety of indications (FXS, FXTAS, POI and carrier status). Thirteen full mutations (>200 repeats) and 34 pre-mutations (59-200 repeats) were identified. All but two of those patients with a full mutation had a known family history of FXS. Of those with a full mutation, five were male and eight were female. Five of the females had symptoms of FXS. Our findings suggest a low diagnostic yield from FMR1 assays, particularly in the absence of a family history. It is also noteworthy that an equal number symptomatic females and males were diagnosed. This may be a reflection of the small sample size and/or ascertainment bias. We propose that FXS testing should not be undertaken as a first line investigation in children with ID, and only sought if there is a high degree of clinical suspicion, or a known family history.