A thematic analysis of alcohol use and culture amongst elite (intercounty) Gaelic Athletic Association (GAA) players.

BACKGROUND: There are limited studies examining alcohol consumption in Gaelic Athletic Association (GAA) players. In a previous paper, we reported excess alcohol consumption, alcohol-related harms and binge drinking amongst elite GAA players. In that survey, the players were provided with an opportunity to provide comments on alcohol. This current study analyses these comments. AIMS: The aim of this study was to provide a qualitative analysis of elite GAA players opinions on alcohol consumption, harms, behaviours and culture. METHODS: An anonymous, web-based e-questionnaire was distributed to all registered adult elite (inter-county) GAA players. This analysed demographics, alcohol consumption, alcohol culture and alcohol-related harms. This paper is a thematic analysis of the players comments on alcohol in the GAA. RESULTS: Seven hundred seventy-three of 3592 (21%) players responded. One hundred fifty-two respondents (21%) commented in the free text section of the survey regarding alcohol. One hundred eleven comments (73%) were suitable for analysis. Relevant themes were a pattern of abstinence and bingeing (n = 44), excess alcohol consumption (n = 40) and drinking bans contributing to a binge drinking culture (n = 37). There was a mixed attitude to alcohol sponsorship. CONCLUSION: These data show players recognise intermittent binge drinking with periods of abstinence and alcohol-related harms. Further initiatives regarding alcohol harm reduction merit consideration including prohibition of alcohol sponsorship, similar to the GAA's ban on gambling.

Developing future clinical leaders in patient safety: the Irish experience.

INTRODUCTION: It is 20 years since the Institute of Medicine advocated a national approach to improve care and patient safety. Patient safety infrastructure has greatly improved in certain countries. In Ireland, patient safety infrastructure is in ongoing development. To contribute to this, the Royal College of Physicians of Ireland/International Society for Quality in Healthcare Scholar in Residence Programme was launched in 2016. This programme aims to improve patient safety and develop a movement of future clinician leaders to drive improvements in patient safety and the quality of care. METHODS: Doctors in postgraduate training complete a year-long immersive mentorship. This involves monthly group meetings with key patient safety opinion makers, one-on-one mentorship, leadership courses, conference attendance and presentations. Each scholar undertakes a quality improvement (QI) project. RESULTS: A QI project was associated with a decrease in caesarean section rates from 13.7% to 7.6% (p=0.0002) among women in spontaneous labour at term with a cephalic presentation. Other projects are ongoing. CONCLUSION: Medical error, patient safety and QI must be addressed comprehensively at both undergraduate and postgraduate level. We believe the Irish mentorship programme will help to change the paradigm and improve patient safety.

Predictors of adverse gambling behaviours amongst elite athletes.

Problem gambling levels amongst elite sportspeople are above populational baseline. We assess gambling in an elite Irish sporting population. An anonymous web-based questionnaire including the validated Problem Gambling Severity Index was distributed. Univariate and multivariate analyses were performed to evaluate predictors of moderate/high risk gambling. 608 players (mean age 24) were included. Seventy nine percent of respondents were current gamblers and 6% problem gamblers. Amongst high-risk gamblers, significantly more were male (100% vs 76%, p = 0.003), fewer completed university (52% vs 69%, p = 0.024), and more were smokers (48% vs 24%, p = 0.002). They were also more likely to avail of free online gambling offers (90% vs 44%, p < 0.001), gamble with teammates (52% vs 21%, p < 0.001) and have placed their first bet before age 16 (41% vs 19%, p = 0.003). In multivariate analysis, moderate/high risk gambling was associated with: male gender (OR = 8.9 [1.1-69], p = 0.035), no 3rd level education (OR = 2.5 [1.4-5.0], p = 0.002), free online gambling use (OR = 4.3 [2.1-5.3], p < 0.001), gambling with teammates (OR = 3.0 [1.7-5.3], p < 0.001), and being under 18 at first bet (OR = 2.0 [1.1-3.3], p = 0.013). This study shows a harmful gambling culture amongst elite Irish athletes. Male gender, lower educational status, free online gambling use, gambling with teammates and first bet at less than age 18 were associated with moderate/high risk gambling. These groups may benefit from targeted interventions.

Harmful alcohol consumption in elite sports players in Ireland.

BACKGROUND: Sportspeople are more prone to binge drink than their peers. AIMS: We aimed to assess alcohol consumption, harms and behaviours in an elite Irish sporting population (Gaelic footballers and hurlers). METHODS: An anonymous web-based questionnaire (demographics, alcohol consumption, culture and related harms) was administered to all elite players. The AUDIT-C questionnaire (frequency, quantity of alcohol consumption and frequency of binge drinking) was used to assess for adverse alcohol use. Univariate and multivariate analyses assessed for predictors of adverse alcohol use. RESULTS: 717 players (mean age 24 years) were analysed. The majority of patients were male (75%), unmarried (93%) and had completed university (67%). 96% were current drinkers. Players consumed more alcohol during the off-season (median 20 versus 8 standard drinks in 28 days) compared to the elite season. Amongst current drinkers, 73% exhibit adverse alcohol use, 93% reported binge drinking and 65% an alcohol related harm in the past year. Most players would turn to family (36%) or friends (21%) for help. There were significant associations between monthly bingeing (OR 18.4), smoking (OR 3.3), generally drinking in public (OR 3.2), current gambling (OR 2.3), male gender (OR 2.1), an alcohol harm in the past year (OR 1.9) and adverse alcohol use. In contrast, co-habiting with a partner (OR 0.5) was protective. CONCLUSIONS: Excess alcohol consumption, alcohol related harms and binge drinking are prevalent in an elite sporting population, particularly during the off-season. Specific strategies are required to reduce alcohol related harms, particularly amongst high-risk groups during the off-season.

Exploring the effect of alcohol on disease activity and outcomes in rheumatoid arthritis through systematic review and meta-analysis.

To evaluate the effects of alcohol consumption on disease activity in rheumatoid arthritis. EMBASE, Pubmed, the Cochrane Library, and Web of Science were searched until July 29, 2020. English language studies that reported disease activity outcomes in rheumatoid arthritis were included. Studies were excluded if they were reviews, case reports, had fewer than 20 patients, or reported on prevalence but not disease activity in RA. Forest plots were used to determine pooled mean difference and were generated on RevMan5.3. Linear regression was used to determine correlations between alcohol and antibody status, gender, and smoking status. The search identified 4126 citations of which 14 were included. The pooled mean difference in DAS28 (95% CI) was 0.34 (0.24, 0.44) (p < 10-5) between drinkers and non-drinkers with lower DAS28 in non-drinkers, 0.33 (0.05, 0.62) (p = 0.02) between heavy drinkers and non-drinkers with lower DAS28 in heavy drinkers, and 0.00 (- 0.30, 0.30) (p = 0.98) between low- and high-risk drinkers. The mean difference of HAQ assessments was significantly different between those who drink alcohol compared to those who do not, with drinkers reporting lower HAQ scores (0.3 (0.18, 0.41), p < 10-5). There was no significant correlation between drinking and gender, smoking status, or antibody positivity. Alcohol consumption is associated with lower disease activity and self-reported health assessment in rheumatoid arthritis. However, drinking has no correlation with smoking, gender, or antibody status.

The effects of alcohol consumption and its associations with disease activity among 979 patients with inflammatory arthritis.

OBJECTIVE: The role of alcohol in inflammatory disease remains debated. This study explores the relationship between alcohol and disease activity in patients with inflammatory arthritis. METHODS: Patients attending a rheumatology clinic between 2010 and 2020 were prospectively followed. Information on demographics, alcohol use, smoking habits and disease outcome measures were collected from these patients. Statistical analysis included univariate and multivariate linear and binary logistic regressions, Mann-Whitney U tests and one-way analysis of variance with Tukey's honest significant difference (HSD) test. RESULTS: Of the 979 analysed patients, 62% had rheumatoid arthritis (RA), 26.7% had psoriatic arthritis (PsA) and 11.2% had ankylosing spondylitis. Mean DAS28-CRP (Disease Activity Score 28 - C-reactive protein) in RA and PsA at 1 year was 2.96±1.39, and 64.2% of patients were in remission (DAS28-CRP ≤2.6 or BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) ≤4). Both male gender and risky drinking (>15 units of weekly alcohol) were significantly associated with remission. Compared with women, men had an OR of 1.8 (1.1, 2.5) (p=0.034) for any alcohol consumption and 6.9 (4.7, 9.1) (p=0.001) for drinking at least 15 weekly drinks. When adjusted for gender, there was no association between alcohol and disease activity. Yet, when adjusted for alcohol consumption, gender still significantly influenced disease activity. CONCLUSION: While it may appear that alcohol is linked to remission in inflammatory arthritis, when adjusted for gender, it is not. Men with inflammatory arthritis drink significantly more than women and have less severe disease activity.

First use of tofacitinib to treat an immune checkpoint inhibitor-induced arthritis.

Immune checkpoint inhibitors have revolutionised cancer treatment; however, immune-related adverse events do occur, with up to 7% developing inflammatory arthritis. Common rheumatoid arthritis therapies such as methotrexate, prednisolone and biologics have been used to treat this arthritis in small, uncontrolled case series with varying success. In this case of personalised medicine, we report the first use of tofacitinib, a small molecular inhibitor of the Janus kinase-signal transducer and activator of transcription pathway, to treat checkpoint inhibitor-related inflammatory arthritis. This resulted in a rapid clinical response and complete, sustained remission of the arthritis with associated marked reduction in synovial molecular and cellular immune response.

Long-term remission and biologic persistence rates: 12-year real-world data.

BACKGROUND: Biologic therapies have greatly improved outcomes in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Yet, our ability to predict long-term remission and persistence or continuation of therapy remains limited. This study explores predictors of remission and persistence of the initial biologic therapy in patients after 12 years. Furthermore, outcomes with adalimumab and etanercept are compared. PATIENTS AND METHODS: RA and PsA patients were prospectively recruited from a biologic clinic. Outcomes on commencing therapy, at 1 year and 12 years were reviewed. Demographics, medications, morning stiffness, patient global health score, tender and swollen joint counts, antibody status, CRP and HAQ were collected. Outcomes at 1 year and 12 years are reported and predictors of biologic persistence and EULAR-defined remission (DAS28-CRP < 2.6) are examined with univariate and multivariate analysis. RESULTS: A total of 403 patients (274 RA and 129 PsA) were analysed. PsA patients were more likely to be male, in full-time employment and have completed higher education. PsA had higher remission rates than RA at both 1 year (60.3% versus 34.5%, p < 0.001) and 12 years (91.3% versus 60.6%, p < 0.001). This difference persisted when patients were matched for baseline disease activity (p < 0.001). Biologic continuation rates were high for RA and PsA at 1 year (49.6% versus 58.9%) and 12 years (38.2% versus 52.3%). In PsA, patients starting on etanercept had lower CRP at 12 years (p = 0.041). Multivariate analysis showed 1-year continuation [OR 4.28 (1.28-14.38)] and 1-year low-disease activity [OR 3.90 (95% CI 1.05-14.53)] was predictive of a 12-year persistence. Persistence with initial biologic at 12 years [OR 4.98 (95% CI 1.83-13.56)] and male gender [OR 4.48 (95% CI 1.25-16.01)] predicted 12 year remission. CONCLUSIONS: This is the first study to show better response to biologic therapy in PsA compared to RA at 12 years. Long-term persistence with initial biologic agent was high and was predicted by biologic persistence and low-disease activity at 1 year. Interestingly, PsA patients had higher levels of employment, educational attainment, and long-term remission rates compared to RA patients.

Rheumatoid arthritis CD14+ monocytes display metabolic and inflammatory dysfunction, a phenotype that precedes clinical manifestation of disease.

INTRODUCTION: This study investigates the metabolic activity of circulating monocytes and their impact on pro-inflammatory responses in RA and explores whether this phenotype is already primed for inflammation before clinical manifestations of disease. METHODS: Blood was collected and CD14+ monocytes isolated from healthy control donors (HC), individuals at-risk (IAR) and RA patients. Monocyte frequency in blood and synovial tissue was assessed by flow cytometry. Inflammatory responses and metabolic analysis ± specific inhibitors were quantified by RT-PCR, Western blot, migration assays, Seahorse-XFe-technology, mitotracker assays and transmission electron microscopy. Transcriptomic analysis was performed on HC, IAR and RA synovial tissue. RESULTS: CD14+ monocytes from RA patients are hyper-inflammatory following stimulation, with significantly higher expression of cytokines/chemokines than those from HC. LPS-induced RA monocyte migratory capacity is consistent with increased monocyte frequency in RA synovial tissue. RA CD14+ monocytes show enhanced mitochondrial respiration, biogenesis and alterations in mitochondrial morphology. Furthermore, RA monocytes display increased levels of key glycolytic enzymes HIF1α, HK2 and PFKFB3 and demonstrate a reliance on glucose consumption, blockade of which abrogates pro-inflammatory mediator responses. Blockade of STAT3 activation inhibits this forced glycolytic flux resulting in metabolic reprogramming and resolution of inflammation. Interestingly, this highly activated monocytic phenotype is evident in IAR of developing disease, in addition to an enhanced monocyte gene signature observed in synovial tissue from IAR. CONCLUSION: RA CD14+ monocytes are metabolically re-programmed for sustained induction of pro-inflammatory responses, with STAT3 identified as a molecular regulator of metabolic dysfunction. This phenotype precedes clinical disease onset and may represent a potential pathway for therapeutic targeting early in disease.

COVID-19 and rheumatic musculoskeletal disease patients: infection rates, attitudes and medication adherence in an Irish population.

OBJECTIVES: To establish, amongst Irish rheumatic musculoskeletal disease (RMD) patients, rates of COVID-19 symptoms and positive tests, DMARD adherence and attitudes to virtual clinics. METHODS: An online survey assessing COVID-19 status, RMD diagnoses, adherence and information sources was disseminated via the Arthritis Ireland website and social media channels. RESULTS: There were 1381 respondents with 74.8% on immunosuppressive medication. Symptoms of COVID-19 were reported by 3.7% of respondents of which 0.46% tested positive, consistent with the general Irish population. The frequency of COVID-19 symptoms was higher for respondents with spondyloarthropathy [odds ratio (OR) 2.06, 95% CI: 1.14, 3.70] and lower in those on immunosuppressive medication (OR 0.48, 95% CI: 0.27, 0.88), and those compliant with health authority (HSE) guidance (OR 0.47, 95% CI: 0.25, 0.89). Adherence to RMD medications was reported in 84.1%, with 57.1% using health authority guidelines for information on medication use. Importantly, adherence rates were higher amongst those who cited guidelines (89.3% vs 79.9%, P <0.001), and conversely lower in those with COVID-19 symptoms (64.0% vs 85.1%, P =0.009). Finally, the use of virtual clinics was supported by 70.4% of respondents. CONCLUSION: The rate of COVID-19 positivity in RMD patients was similar to the general population. COVID-19 symptoms were lower amongst respondents on immunosuppressive medication and those adherent to medication guidelines. Respondents were supportive of HSE advice and virtual clinics.

Pathogenic, glycolytic PD-1+ B cells accumulate in the hypoxic RA joint.

While autoantibodies are used in the diagnosis of rheumatoid arthritis (RA), the function of B cells in the inflamed joint remains elusive. Extensive flow cytometric characterization and SPICE algorithm analyses of single-cell synovial tissue from patients with RA revealed the accumulation of switched and double-negative memory programmed death-1 receptor-expressing (PD-1-expressing) B cells at the site of inflammation. Accumulation of memory B cells was mediated by CXCR3, evident by the observed increase in CXCR3-expressing synovial B cells compared with the periphery, differential regulation by key synovial cytokines, and restricted B cell invasion demonstrated in response to CXCR3 blockade. Notably, under 3% O2 hypoxic conditions that mimic the joint microenvironment, RA B cells maintained marked expression of MMP-9, TNF, and IL-6, with PD-1+ B cells demonstrating higher expression of CXCR3, CD80, CD86, IL-1ß, and GM-CSF than their PD-1- counterparts. Finally, following functional analysis and flow cell sorting of RA PD-1+ versus PD-1- B cells, we demonstrate, using RNA-Seq and emerging fluorescence lifetime imaging microscopy of cellular NAD, a significant shift in metabolism of RA PD-1+ B cells toward glycolysis, associated with an increased transcriptional signature of key cytokines and chemokines that are strongly implicated in RA pathogenesis. Our data support the targeting of pathogenic PD-1+ B cells in RA as a focused, novel therapeutic option.

A multidisciplinary approach to reproductive healthcare in women with rheumatic disease.

INTRODUCTION: Rheumatic disease (RD) patients when family planning must consider fertility, disease activity, and management from preconception to lactation. A clear understanding is necessary, especially for those receiving disease-modifying antirheumatic medications. Previous studies have highlighted unmet needs in the care of women with RDs with reproductive healthcare needs. This study describes the first published standardized reproductive care pathway for women with RDs and the outcomes of this approach. MATERIAL AND METHODS: We developed the care pathway with multidisciplinary input from rheumatologists, rheumatology nurse specialists, obstetricians, midwives, maternal medicine specialists, and pharmacists. We identified patients' emotional and healthcare needs, ensured access to expert advice, maintenance of good disease control, and positive reproductive outcomes. We prospectively followed the patients and report the results of the service. RESULTS: Ninety-eight women with median age (range) of 35 years (19-48) were assessed. The majority had an inflammatory arthritis. Seventy-six babies were born to 62 mothers. There were 12 miscarriages and one perinatal death. Breastfeeding rates at 6 weeks were low (28%). CONCLUSION: We describe the first published evidence-based integrated multidisciplinary reproductive care pathway for women with RDs and the results of this approach. Seventy percent of women successful in trying to conceive delivered a healthy baby, and 90% of patients were 'very satisfied' with the service.

A quality improvement intervention failed to significantly increase pneumococcal and influenza vaccination rates in immunosuppressed inflammatory arthritis patients.

OBJECTIVES: Pneumococcal and influenza vaccination rates have been suboptimal in studies of immunosuppressed patients. We aimed to assess barriers to and increase rates of 23-valent pneumococcal polysaccharide vaccine (PPSV23) and influenza vaccination in this group. The primary endpoint was a statistically significant increase in adequate PPSV23 and influenza vaccination. METHODS: In 2017, rheumatology outpatients completed an anonymous questionnaire recording vaccination knowledge, status, and barriers. Simultaneously, a low-cost multifaceted quality improvement (QI) intervention was performed. All outpatients on oral steroids, immunosuppressant conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or biologics disease-modifying antirheumatic drugs (bDMARDs) were included in the study. In 2018, post-intervention, the clinic was re-assessed. Demographics, diagnosis, medications, smart phone access, and willingness to use this for vaccination reminders were assessed for independent vaccination predictors using binary logistic regression analysis. RESULTS: Four hundred twenty-five patients were included (72.6% rheumatoid arthritis, 74% women, 45.6% ≥ 60 years old). From 2017 to 2018, PPSV23 vaccination rates changed from 41.0 to 47.2% (P = 0.29) and influenza from 61.8 to 62.1% (P = 0.95). The most common reason for non-vaccination was lack of awareness. Following the intervention, this changed for influenza (36.7 to 34.2%) and PPSV23 (82.1 to 76.4%). General practitioners performed most vaccinations, only 3.6% were delivered in the hospital. Significant predictors of PPSV23 vaccination were older age {≥ 80 years had an OR 41.66 (95% CI 3.69-469.8, P = 0.003), compared with ≤ 39 years}, bDMARD use (OR 2.80, 95% CI 1.24-6.32, P = 0.013), and adequate influenza vaccination (OR 9.01, 95% CI 4.40-18.42, P < 0.001). Up-to-date PPSV23 vaccination (OR 8.93, 95% CI 4.39-18.17, P < 0.001) predicted influenza vaccination. CONCLUSIONS: PPSV23 and influenza vaccination rates were suboptimal. The intervention did not cause a statistically significant change in vaccination rates. Point-of-care vaccination may be more effective.Key Points• Low vaccination rates amongst immunosuppressed inflammatory arthritis outpatients• Less than 5% of vaccinations occurred in hospital• There was no statistically significant difference in the rates of adequate PPSV23 (41.0 to 47.2%) or influenza (61.8 to 62.1%) vaccination following our intervention.

Readability and Quality of Online Information on Osteoarthritis: An Objective Analysis With Historic Comparison.

BACKGROUND: Osteoarthritis (OA) is the most common cause of disability in people older than 65 years. Readability of online OA information has never been assessed. A 2003 study found the quality of online OA information to be poor. OBJECTIVE: The aim of this study was to review the readability and quality of current online information regarding OA. METHODS: The term osteoarthritis was searched across the three most popular English language search engines. The first 25 pages from each search engine were analyzed. Duplicate pages, websites featuring paid advertisements, inaccessible pages (behind a pay wall, not available for geographical reasons), and nontext pages were excluded. Readability was measured using Flesch Reading Ease Score, Flesch-Kincaid Grade Level, and Gunning-Fog Index. Website quality was scored using the Journal of the American Medical Association (JAMA) benchmark criteria and the DISCERN criteria. Presence or absence of the Health On the Net Foundation Code of Conduct (HONcode) certification, age of content, content producer, and author characteristics were noted. RESULTS: A total of 37 unique websites were found suitable for analysis. Readability varied by assessment tool from 8th to 12th grade level. This compares with the recommended 7th to 8th grade level. Of the 37, 1 (2.7%) website met all 4 JAMA criteria. Mean DISCERN quality of information for OA websites was "fair," compared with the "poor" grading of a 2003 study. HONcode-endorsed websites (43%, 16/37) were of a statistically significant higher quality. CONCLUSIONS: Readability of online health information for OA was either equal to or more difficult than the recommended level.

Updated pharmacological management of rheumatoid arthritis for women before, during, and after pregnancy, reflecting recent guidelines.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disease which can cause significant disability, morbidity, mortality, and impaired fertility. It commonly affects women of childbearing age. Managing rheumatoid arthritis (RA) in the perinatal period poses challenges. There is concern about the teratogenic effects of many traditional disease-modifying anti-rheumatic drugs (DMARDs) and an ever-growing list of new therapeutic options with limited data in pregnancy and breastfeeding. AIMS: We aimed to create a standardized approach to pharmacological management of RA patients seen in our newly established Rheumatology and Reproductive Health Service. METHODS: We reviewed relevant publications on the use of anti-rheumatic drugs in pregnancy. These include recent guidelines from The British Society for Rheumatology (BSR) and British Health Professionals in Rheumatology (BHPR) and the European League Against Rheumatism (EULAR). RESULTS: After considering relevant publications, we developed a Saint Vincent's University Hospital/National Maternity Hospital consensus protocol for evidence-based medication in pregnancy in RA. CONCLUSIONS: RA tends to improve during pregnancy and flare postpartum. Several anti-rheumatic medication options during pregnancy and breastfeeding are now available including anti-tumor necrosis factor (anti-TNF) agents. Good disease control at all stages of reproduction is important to ensure best outcome for both mother and baby.

Influence of gamma and electron beam sterilization on the stability of a premixed injectable calcium phosphate cement for trauma indications.

Premixed calcium phosphate cements (CPC's) are becoming the material of choice for injectable cements as a result of their effective delivery to the target implantation site. For orthopaedic use, it is of vital importance that the attributes of these CPC's are not compromised by irradiation sterilization. Therefore, the aim of this study is to determine the influence of irradiation sterilization on a range of premixed CPC's, with an emphasis on improving product shelf life through the use of optimal packaging configurations and annealing steps. Electron spin resonance (ESR) confirmed the presence of free radicals in the inorganic phase of the CPC paste following irradiation. The inclusion of a 24-h annealing step was the only successful method in reducing the degree of free radical formation. Based on the results of injectability force testing, it was revealed that an annealing step greater than 24-h significantly altered the viscosity, however; at 24-h the key attributes of the CPC paste were minimally effected. Overall, it was established that vacuum packing the CPC paste, placing the contents into a foil pouch, gamma irradiating at the minimal dose required and using an annealing step of ≤ 24-h, has the potential to extend the shelf life of the cement.

Synthesis, characterisation and phase transition behaviour of temperature-responsive physically crosslinked poly (N-vinylcaprolactam) based polymers for biomedical applications.

Poly (N-vinylcaprolactam) (PNVCL) is a polymer which offers superior characteristics for various potential medical device applications. In particular it offers unique thermoresponsive capabilities, which fulfils the material technology constraints required in targeted drug delivery applications. PNVCL phase transitions can be tailored in order to suit the requirements of current and next generation devices, by modifying the contents with regard to the material composition and aqueous polymer concentration. In this study, physically crosslinked Poly (N-vinylcaprolactam)-Vinyl acetate (PNVCL-VAc) copolymers were prepared by photopolymerisation. The structure of the polymers was established by Fourier transform infrared spectroscopy, nuclear magnetic resonance and gel permeation chromatography. The polymers were further characterised using differential scanning calorimetry and swelling studies. Determination of the LCST of the polymers in aqueous solution was achieved by employing four techniques; cloud point, UV-spectrometry, differential scanning calorimetry and rheometry. Sol-gel transition was established using tube inversion method and rheological analysis. This study was conducted to determine the characteristics of PNVCL with the addition of VAc, and to establish the effects on the phase transition. The PNVCL based polymers exhibited a decrease in the LCST as the composition of VAc increased. Sol-gel transition could be controlled by altering the monomeric feed ratio and polymer concentration in aqueous milieu. Importantly all copolymers (10wt% in solution) underwent gelation between 33.6 and 35.9°C, and based on this and the other materials properties recorded in this study, these novel copolymers have potential for use as injectable in situ forming drug delivery systems for targeted drug delivery.

Effects of temperature, packaging and electron beam irradiation processing conditions on the property behaviour of Poly (ether-block-amide) blends.

The radiation stability of Poly (ether-block-amide) (PEBA) blended with a multifunctional phenolic antioxidant and a hindered amide light stabiliser was examined under various temperatures, packaging and electron beam processing conditions. FTIR revealed that there were slight alterations to the PEBA before irradiation; however, these became more pronounced following irradiation. The effect of varying the temperature, packaging and processing conditions on the resultant PEBA properties was apparent. For example, rheology demonstrated that the structural properties could be enhanced by manipulating the aforementioned criteria. Mechanical testing exhibited less radiation resistance when the PEBA samples were vacuum packed and exposed to irradiation. MFI and AFM confirmed that the melting strength and surface topography could be reduced/increased depending on the conditions employed. From this study it was concluded that virgin PEBA submerged in dry ice with non-vacuum packaging during the irradiation process, provided excellent radiation resistance (20.9% improvement) in contrast to the traditional method.