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Perceptions of online surgical-focused learning amongst surgeons during the COVID pandemic: A scoping review 2020-22. Surgeon 2024; 22:e94-e99. [PMID: 38142195 DOI: 10.1016/j.surge.2023.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 12/25/2023]
Abstract
INTRODUCTION During the COVID pandemic many centres adopted e-learning as a tool to adhere to social distancing recommendations while continuing to provide ongoing postgraduate medical education. We aimed to complete this scoping review in order to map experience and perceptions amongst surgeons and surgical trainees to remote learning during the COVID pandemic. METHODS Using Arksey and O'Malley's five step model for conducting a scoping review, a systematic search strategy was undertaken across three online databases SCOPUS, MEDLINE and Web of Science. Only original articles in English in the field of postgraduate education in surgery were included. RESULTS 44 studies were selected for review. Of these 44, 21 were studies of perception of a newly developed e-learning tool/platform. 17 were surveys of surgeon's attitudes towards e-learning during the COVID pandemic. The remaining 6 studies were studies of knowledge or skills acquired through new e-learning, which included a survey of experience. The United States was the most common country of origin with General Surgery the most represented surgical speciality. Response rates across all three study subgroups were on average >60%. Surgeon's experience of e-learning was reported in only positive terms in 86% (n = 38/44) of studies. CONCLUSIONS This paper is informative in that it focuses specifically on surgeons' perceptions of a e-learning tools used in addition to skills or knowledge gained. Positive e-learning experience reported in these studies may lead to more blended learning curriculums being developed, deployed and evaluated going forward.
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The Role of Physician and Practice Characteristics in the Quality of Diabetes Management in Primary Care: Systematic Review and Meta-analysis. J Gen Intern Med 2020; 35:1836-1848. [PMID: 32016700 PMCID: PMC7280455 DOI: 10.1007/s11606-020-05676-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 12/03/2019] [Accepted: 01/19/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND Despite evidence-based guidelines, high-quality diabetes care is not always achieved. Identifying factors associated with the quality of management in primary care may inform service improvements, facilitating the tailoring of quality improvement interventions to practice needs and resources. METHODS We searched MEDLINE, EMBASE, CINAHL and Web of Science from January 1990 to March 2019. Eligible studies were cohort studies, cross-sectional studies and randomised controlled trials (baseline data) conducted among adults with diabetes, which examined the relationship between any physician and/or practice factors and any objective measure(s) of quality. Studies which examined patient factors only were ineligible. Where possible, data were pooled using random-effects meta-analysis. RESULTS In total, 82 studies were included. The range of individual quality measures and the construction of composite measures varied considerably. Female physicians compared with males ((odds ratio (OR) = 1.07, 95% CI: 1.04, 1.10), 8 studies), physicians with higher diabetes volume compared with lower volume (OR = 1.24, 95% CI: 1.05-1.47, 4 studies) and practices with Electronic Health Records (EHR) versus practices without (OR = 1.43, 95% CI: 1.11-1.84, 4 studies) were associated with a higher quality of care. There was no association between physician experience, practice location and type of practice and quality. Based on the narrative synthesis, increasing physician age and higher practice socio-economic deprivation may be associated with lower quality of care. DISCUSSION Identification of physician- and practice-level factors associated with the quality of care (female gender, younger age, physician-level diabetes volume, practice deprivation and EHR use) may explain differences across practices and physicians, provide potential targets for quality improvement interventions and indicate which practices need specific supports to deliver improvements in diabetes care.
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Abstract
Background Failure of endovascular aneurysm repair may require explant of the stent graft in a subset of patients. We sought to assess outcomes in a cohort of patients undergoing explant of endovascular aneurysm repair in both emergency and elective settings. Methods Patients undergoing explant of endovascular aneurysm repair were identified from a prospectively maintained database, with additional information obtained through retrospective analysis of medical records. Results Over a 21-year period, 1997–2018 (May), there were 597 endovascular aneurysm repair procedures performed in our institution for abdominal aortic aneurysm. There were 19 endovascular aneurysm repair explants; five of these were referrals from other vascular centres. The median age was 73 years (range 46–81). The median length of time from insertion to explant was 39.2 months (range 0–153). Indications for elective explant were type Ia endoleak (n = 4), type 1b endoleak (n = 1), type II endoleak with increasing sac size (n = 1), type I/III endoleak (n = 1), type IV endoleak (n = 1), and increasing sac size without evident endoleak (type V, n = 2). The remaining nine cases were emergency procedures, with four patients presenting with rupture post endovascular aneurysm repair, four patients presenting with acute stent thrombosis, of which one also had a type 1a endoleak and one aorto-enteric fistula. There were no mortalities in the elective group and three mortalities in the emergency group (0 vs 33.3%, p = 0.087). Overall 30-day mortality was 15.8% Conclusion Explant of aortic stent grafts can be associated with high mortality and morbidity rates, especially in the emergent setting. Patient and device selection and post-operative surveillance remain vitally important to optimise outcomes post endovascular aneurysm repair.
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β-Branched Amino Acids Stabilize Specific Conformations of Cyclic Hexapeptides. Biophys J 2019; 116:433-444. [PMID: 30661666 DOI: 10.1016/j.bpj.2018.12.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/19/2018] [Accepted: 12/13/2018] [Indexed: 01/11/2023] Open
Abstract
Cyclic peptides (CPs) are a promising class of molecules for drug development, particularly as inhibitors of protein-protein interactions. Predicting low-energy structures and global structural ensembles of individual CPs is critical for the design of bioactive molecules, but these are challenging to predict and difficult to verify experimentally. In our previous work, we used explicit-solvent molecular dynamics simulations with enhanced sampling methods to predict the global structural ensembles of cyclic hexapeptides containing different permutations of glycine, alanine, and valine. One peptide, cyclo-(VVGGVG) or P7, was predicted to be unusually well structured. In this work, we synthesized P7, along with a less well-structured control peptide, cyclo-(VVGVGG) or P6, and characterized their global structural ensembles in water using NMR spectroscopy. The NMR data revealed a structural ensemble similar to the prediction for P7 and showed that P6 was indeed much less well-structured than P7. We then simulated and experimentally characterized the global structural ensembles of several P7 analogs and discovered that β-branching at one critical position within P7 is important for overall structural stability. The simulations allowed deconvolution of thermodynamic factors that underlie this structural stabilization. Overall, the excellent correlation between simulation and experimental data indicates that our simulation platform will be a promising approach for designing well-structured CPs and also for understanding the complex interactions that control the conformations of constrained peptides and other macrocycles.
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Abstract
AIMS To estimate the health service use and direct healthcare costs attributable to diabetes using best available data and methods. METHODS A nationally representative sample of adults aged ≥50 years was analysed (n=8107). Health service use in the previous 12 months included the number of general practitioner visits, outpatient department visits, hospital admissions, and accident and emergency department attendances. Multivariable negative binomial regression was used to estimate the associations between diabetes and frequency of visits. Average marginal effects were applied to unit costs for each health service and extrapolated to the total population, calculating the incremental costs associated with diabetes. RESULTS The prevalence of diabetes was 8.0% (95% CI: 7.4, 8.6). In fully adjusted models, diabetes was associated with additional health service use. Compared to those without diabetes, people with diabetes have, on average, 1.49 (95% CI: 1.10, 1.88) additional general practitioner visits annually. Diabetes was associated with an 87% increase in outpatient visits, a 52% increase in hospital admissions and a 33% increase in accident and emergency department attendances (P<0.001). The incremental cost of this additional service use, nationally, is an estimated €88,894,421 annually, with hospital admissions accounting for 67% of these costs. CONCLUSION Using robust methods, we identified substantially increased service use attributable to diabetes across the health system. Our findings highlight the urgent need to invest in the prevention and management of diabetes.
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Destabilized adaptive influenza variants critical for innate immune system escape are potentiated by host chaperones. PLoS Biol 2018; 16:e3000008. [PMID: 30222731 PMCID: PMC6160216 DOI: 10.1371/journal.pbio.3000008] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 09/27/2018] [Accepted: 08/30/2018] [Indexed: 11/24/2022] Open
Abstract
The threat of viral pandemics demands a comprehensive understanding of evolution at the host-pathogen interface. Here, we show that the accessibility of adaptive mutations in influenza nucleoprotein at fever-like temperatures is mediated by host chaperones. Particularly noteworthy, we observe that the Pro283 nucleoprotein variant, which (1) is conserved across human influenza strains, (2) confers resistance to the Myxovirus resistance protein A (MxA) restriction factor, and (3) critically contributed to adaptation to humans in the 1918 pandemic influenza strain, is rendered unfit by heat shock factor 1 inhibition-mediated host chaperone depletion at febrile temperatures. This fitness loss is due to biophysical defects that chaperones are unavailable to address when heat shock factor 1 is inhibited. Thus, influenza subverts host chaperones to uncouple the biophysically deleterious consequences of viral protein variants from the benefits of immune escape. In summary, host proteostasis plays a central role in shaping influenza adaptation, with implications for the evolution of other viruses, for viral host switching, and for antiviral drug development.
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Understanding and designing head-to-tail cyclic peptides. Biopolymers 2018; 109:e23113. [PMID: 29528114 PMCID: PMC6135719 DOI: 10.1002/bip.23113] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 02/23/2018] [Accepted: 02/26/2018] [Indexed: 01/30/2023]
Abstract
Cyclic peptides (CPs) are an exciting class of molecules with a variety of applications. However, design strategies for CP therapeutics, for example, are generally limited by a poor understanding of their sequence-structure relationships. This knowledge gap often leads to a trial-and-error approach for designing CPs for a specific purpose, which is both costly and time-consuming. Herein, we describe the current experimental and computational efforts in understanding and designing head-to-tail CPs along with their respective challenges. In addition, we provide several future directions in the field of computational CP design to improve its accuracy, efficiency and applicability. These advances, combined with experimental techniques, shall ultimately provide a better understanding of these interesting molecules and a reliable working platform to rationally design CPs with desired characteristics.
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Sustaining quality in the community: trends in the performance of a structured diabetes care programme in primary care over 16 years. Diabet Med 2018; 35:1078-1086. [PMID: 29706032 DOI: 10.1111/dme.13658] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/23/2018] [Indexed: 11/28/2022]
Abstract
AIM To examine the quality of care delivered by a structured primary care-led programme for people with Type 2 diabetes mellitus in 1999-2016. METHODS The Midland Diabetes Structured Care Programme provides structured primary care-led management. Trends over time in care processes were examined (using a chi-squared trend test and age- and gender-adjusted logistic regression). Screening and annual review attendance were reviewed. A composite of eight National Institute for Health and Care Excellence-recommended processes was used as a quality indicator. Participants who were referred to diabetes nurse specialists were compared with those not referred (Student's t-test, Pearson's chi-squared test, Wilcoxon-Mann-Whitney test). Proportions achieving outcome targets [HbA1c ≤58 mmol/mol (7.5%), blood pressure ≤140/80 mmHg, cholesterol <5.0 mmol/l] were calculated. RESULTS Data were available for people with diabetes aged ≥18 years: 1998/1999 (n=336); 2003 (n=843); 2008 (n=988); and 2016 (n=1029). Recording of some processes improved significantly over time (HbA1c , cholesterol, blood pressure, creatinine), and in 2016 exceeded 97%. Foot assessment and annual review attendance declined. In 2016, only 29% of participants had all eight National Institute for Health and Care Excellence processes recorded. A higher proportion of people with diabetes who were referred to a diabetes nurse specialist had poor glycaemic control compared with those not referred. The proportions meeting blood pressure and lipid targets increased over time. CONCLUSIONS Structured primary care led to improvements in the quality of care over time. Poorer recording of some processes, a decline in annual review attendance, and participants remaining at high risk suggest limits to what structured care alone can achieve. Engagement in continuous quality improvement to target other factors, including attendance and self-management, may deliver further improvements.
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Abstract
Cyclic peptides are a promising class of molecules for unique applications. Unfortunately, cyclic peptide design is severely limited by the difficulty in predicting the conformations they will adopt in solution. In this work, we use explicit-solvent molecular dynamics simulations to design well-structured cyclic peptides by studying their sequence-structure relationships. Critical to our approach is an enhanced sampling method that exploits the essential transitional motions of cyclic peptides to efficiently sample their conformational space. We simulated a range of cyclic pentapeptides from all-glycine to a library of cyclo-(X1X2AAA) peptides to map their conformational space and determine cooperative effects of neighboring residues. By combining the results from all cyclo-(X1X2AAA) peptides, we developed a scoring function to predict the structural preferences for X1-X2 residues within cyclic pentapeptides. Using this scoring function, we designed a cyclic pentapeptide, cyclo-(GNSRV), predicted to be well structured in aqueous solution. Subsequent circular dichroism and NMR spectroscopy revealed that this cyclic pentapeptide is indeed well structured in water, with a nuclear Overhauser effect and J-coupling values consistent with the predicted structure.
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Mapping the sequence-structure relationships of simple cyclic hexapeptides. Phys Chem Chem Phys 2018; 19:3315-3324. [PMID: 28091629 DOI: 10.1039/c6cp06192c] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cyclic peptides are promising protein-protein interaction modulators with high binding affinities and specificities, as well as enhanced stabilities and oral availabilities over linear analogs. Despite their relatively small size and cyclic architecture, it is currently difficult to predict the favored conformation(s) of most classes of cyclic peptides. An improved understanding of the sequence-structure relationships for cyclic peptides will offer an avenue for the rational design of cyclic peptides as possible therapeutics. In this work, we systematically explored the sequence-structure relationships for two cyclic hexapeptide systems using molecular dynamics simulation techniques. Starting with an all-glycine cyclic hexapeptide, cyclo-G6, we systematically replaced glycine residues with alanines and characterized the structural ensembles of different variants. The same process was repeated with valines to investigate the effects of larger side chains. An analysis of the origin of structure preferences was performed using thermodynamics decomposition and several general observations are reported.
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Abstract
Cyclic peptides have unique properties and can target protein surfaces specifically and potently. N-Methylation provides a promising way to further optimize the pharmacokinetic and structural profiles of cyclic peptides. The capability to accurately model structures adopted by N-methylated cyclic peptides would facilitate rational design of this interesting and useful class of molecules. We apply molecular dynamics simulations with advanced enhanced sampling methods to efficiently characterize the structural ensembles of N-methylated cyclic peptides, while simultaneously evaluating the overall performance of several simulation force fields. We find that one of the residue-specific force fields, RSFF2, is able to recapitulate experimental structures of the N-methylated cyclic peptide benchmarks tested here when the correct amide isomers are used as initial configurations and enforced during the simulations. Thus, using our simulation approach, it is possible to accurately and efficiently predict the structures of N-methylated cyclic peptides if sufficient information is available to determine the correct amide cis/trans configuration. Moreover, our results suggest that, upon further optimization of RSFF2 to more reliably predict cis/trans isomers, molecular dynamics simulations will be able to de novo predict N-methylated cyclic peptides in the near future, strongly motivating such continued optimization.
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Predictions for α-Helical Glycopeptide Design from Structural Bioinformatics Analysis. J Chem Inf Model 2017; 57:2598-2611. [DOI: 10.1021/acs.jcim.7b00123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
Predicting and constraining RNA virus evolution require understanding the molecular factors that define the mutational landscape accessible to these pathogens. RNA viruses typically have high mutation rates, resulting in frequent production of protein variants with compromised biophysical properties. Their evolution is necessarily constrained by the consequent challenge to protein folding and function. We hypothesized that host proteostasis mechanisms may be significant determinants of the fitness of viral protein variants, serving as a critical force shaping viral evolution. Here, we test that hypothesis by propagating influenza in host cells displaying chemically-controlled, divergent proteostasis environments. We find that both the nature of selection on the influenza genome and the accessibility of specific mutational trajectories are significantly impacted by host proteostasis. These findings provide new insights into features of host–pathogen interactions that shape viral evolution, and into the potential design of host proteostasis-targeted antiviral therapeutics that are refractory to resistance. Influenza viruses, commonly called flu, can evade our immune system and develop resistance to treatments by changing frequently. Specifically, mutations in their genome cause influenza proteins to change in ways that can help the virus evade our defences. However, these mutations come at a cost and can prevent the viral proteins from forming functional and stable three-dimensional shapes – a process known as protein folding – thereby hampering the virus’ ability to replicate. In human cells, proteins called chaperones can help our other proteins fold properly. Influenza viruses do not have their own chaperones and, instead, hijack those of their host. Host chaperones are therefore crucial to the virus’ ability to replicate. However, until now, it was not known if host chaperones can influence how these viruses evolve. Here, Phillips et al. used mammalian cells to study how host chaperones affect an evolving influenza population. First, cells were engineered to either have normal chaperone levels, elevated chaperone levels, or inactive chaperones. Next, the H3N2 influenza strain was grown in these different conditions for nearly 200 generations and sequenced to determine how the virus evolved in each distinctive host chaperone environment. Phillips et al. discovered that host chaperones affect the rate at which mutations accumulate in the influenza population, and also the types of mutations in the influenza genome. For instance, when a chaperone called Hsp90 was inactivated, mutations became prevalent in the viral population more slowly than in cells with normal or elevated chaperone levels. Moreover, some specific mutations fared better in cells with high chaperone levels, whilst others worked better in cells with inactivated chaperones. These results suggest that influenza evolution is affected by host chaperone levels in complex and important ways. Moreover, whether chaperones will promote or hinder the effects of any single mutation is difficult to predict ahead of time. This discovery is significant, as the chaperones available to influenza can vary in different tissues, organisms and infectious conditions, and may therefore influence the virus' ability to change and evolve in a context-specific manner. The findings are likely to extend to other viruses such as HIV and Ebola, which also hijack host chaperones for the same purpose. More work is now needed to systematically quantify these effects so that we can better predict how specific chaperones will affect the ability of viruses to adapt, especially in pathologically relevant conditions like fever or viral host-switching. In the future, such insights could help shape the design of treatments to which viruses do not evolve resistance.
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OP15 Long term outcomes and mortality among patients enrolled in a structured primary care-led diabetes programme. Health Serv Res 2017. [DOI: 10.1136/jech-2017-ssmabstracts.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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OP16 Challenges experienced by community-based clinical nurse specialists in supporting the delivery of integrated diabetes care: a qualitative study. Health Serv Res 2017. [DOI: 10.1136/jech-2017-ssmabstracts.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Barriers and facilitators to initial and continued attendance at community-based lifestyle programmes among families of overweight and obese children: a systematic review. Obes Rev 2017; 18:183-194. [PMID: 27862851 PMCID: PMC5245104 DOI: 10.1111/obr.12478] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 08/04/2016] [Accepted: 09/20/2016] [Indexed: 12/13/2022]
Abstract
The success of childhood weight management programmes relies on family engagement. While attendance offers many benefits including the support to make positive lifestyle changes, the majority of families referred to treatment decline. Moreover, for those who do attend, benefits are often compromised by high programme attrition. This systematic review investigated factors influencing attendance at community-based lifestyle programmes among families of overweight or obese children. A narrative synthesis approach was used to allow for the inclusion of quantitative, qualitative and mixed-method study designs. Thirteen studies met the inclusion criteria. Results suggest that parents provided the impetus for programme initiation, and this was driven largely by a concern for their child's psychological health and wellbeing. More often than not, children went along without any real reason or interest in attending. Over the course of the programme, however, children's positive social experiences such as having fun and making friends fostered the desire to continue. The stigma surrounding excess weight and the denial of the issue amongst some parents presented barriers to enrolment and warrant further study. This study provides practical recommendations to guide future policy makers, programme delivery teams and researchers in developing strategies to boost recruitment and minimise attrition.
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Emergency endovascular management of acute thoracic aortic pathology A safe and feasible option. Surgeon 2016; 15:325-328. [PMID: 28034631 DOI: 10.1016/j.surge.2016.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 10/16/2016] [Indexed: 11/19/2022]
Abstract
Endovascular repair has revolutionised the emergency treatment of thoracic aortic disease. We report our 10 year experience using this treatment in emergency cases. A prospectively maintained vascular database was analysed. Patients' medical records and CT images stored on the hospital PACS system were also reviewed. Statistical analysis was done using IBM SPSS V21. There were a total of 59 thoracic aortic stenting procedures of which 33 (60% males with a mean age of 58 yrs) were performed for emergency thoracic pathologies: traumatic transection (n = 10), ruptured aneurysm (n = 6), non-traumatic dissection (n = 8) and penetrating aortic ulcer (n = 9). All patients had self-expanding endografts implanted. Two patients required debranching procedures before the endovascular treatment. Thirty-day mortality was 12.1% (4/33). 70% of patients received a single device. There were 7 procedure related complications, 6 requiring re-intervention: thoracotomy and drainage in 2 patients, proximal graft extension in 2, open drainage of groin haematoma in 1 and open repair of a common femoral artery pseudo-aneurysm in one patient. In total 23 patients were transferred from 11 centres nationwide. There were no mortalities or other complications related to patient transfer from peripheral centres. Although acute thoracic aortic pathology is life threatening, appropriate blood pressure management and treatment of associated injuries can result in favourable outcomes. Endovascular repair is a safe and effective treatment option which enables patients to be treated with reduced morbidity and mortality. Transfer of patients with acute pathology to a tertiary centre can safely be performed.
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Trends in blindness due to diabetic retinopathy among adults aged 18-69years over a decade in Ireland. Diabetes Res Clin Pract 2016; 121:1-8. [PMID: 27612011 DOI: 10.1016/j.diabres.2016.08.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 07/27/2016] [Accepted: 08/19/2016] [Indexed: 11/17/2022]
Abstract
AIMS To describe trends in the incidence of visual impairment and blindness due to diabetic retinopathy among adults aged 18-69years in Ireland between 2004 and 2013. METHODS Data on visual impairment due to diabetic retinopathy in adults aged 18-69years or over who are registered with the National Council for the Blind of Ireland, (2004-2013) were analysed. Annual incidence rates were calculated for the adult population and the population with diagnosed diabetes. Poisson regression was used to test for changes in rates over time. The relative, attributable and population risk of blindness and visual impairment due to diabetic retinopathy were calculated for 2013. RESULTS Over the decade, the prevalence of diagnosed diabetes increased from 2.1% to 3.6%. Among people with diagnosed diabetes, the incidence of visual impairment due to diabetic retinopathy increased from 6.4 (95% CI 2.4-13.9) per 100,000 in 2004 to 11.7 (95% CI 5.9-21.0) per 100,000 in 2013. The incidence of blindness due to diabetic retinopathy varied from 31.9 per 100,000 (95% CI 21.6-45.7) in 2004 to 14.9 per 100,000 (95% CI 8.2-25.1) in 2013. CONCLUSIONS Our findings indicate the need for increased attention to preventive measures for microvascular complications among adults with diabetes in Ireland. Retinopathy screening has been standardised in Ireland, these findings provide useful baseline statistics to monitor the impact of this population-based screening programme.
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Endovascular versus open repair of ruptured abdominal aortic aneurysm. Surgeon 2016; 14:274-7. [PMID: 26141726 DOI: 10.1016/j.surge.2015.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 05/07/2015] [Accepted: 05/24/2015] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Endovascular aneurysm repair (EVAR) is a comparatively less invasive technique than open repair (OR). Debate remains with regard to the benefit of EVAR for patients with ruptured abdominal aortic aneurysm (RAAA). We sought to evaluate and report outcomes of EVAR for RAAA in an Irish tertiary vascular referral centre. METHODS Patients undergoing emergency surgery for ruptured or symptomatic AAA were identified from theatre logbooks and HIPE database. Retrospective chart review was undertaken. Data were exported to IBM SPSS version 21 for statistical analysis with p < 0.05 considered significant. RESULTS A total of 41 patients underwent surgery for RAAA. The mean age was 74 years old with a range from 55 to 89 years. The majority (n = 25, 61%) were baseline American Society of Anaesthesiology (ASA) grade 3-4. Of these 56% underwent EVAR with the remaining 44% repaired open. Mortality rate in those undergoing emergency EVAR was 34.8%, compared with 38.9% in those undergoing open surgery. This difference was not statistically significant. The mean overall length of stay was 13 days. With regard to prognostic indicators of patient outcome, increasing patient age was noted to be significantly associated with increased mortality (p = 0.013), as was increased ASA score at time of surgery (p = 0.029). CONCLUSIONS Mortality rates in those undergoing EVAR for RAAA are comparable with those undergoing open repair. Increasing age and ASA score are significant predictors of mortality in patients with RAAA undergoing intervention.
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Computational methods to design cyclic peptides. Curr Opin Chem Biol 2016; 34:95-102. [PMID: 27592259 DOI: 10.1016/j.cbpa.2016.08.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/08/2016] [Accepted: 08/10/2016] [Indexed: 10/21/2022]
Abstract
Cyclic peptides (CPs) are promising modulators of protein-protein interactions (PPIs), but their application remains challenging. It is currently difficult to predict the structures and bioavailability of CPs. The ability to design CPs using computer modeling would greatly facilitate the development of CPs as potent PPI modulators for fundamental studies and as potential therapeutics. Herein, we describe computational methods to generate CP libraries for virtual screening, as well as current efforts to accurately predict the conformations adopted by CPs. These advances are making it possible to envision robust computational design of active CPs. However, unique properties of CPs pose significant challenges associated with sampling CP conformational space and accurately describing CP energetics. These major obstacles to structure prediction likely must be solved before robust design of active CPs can be reliably achieved.
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P104 Trends in the Quality of Structure Diabetes Care in Primary Care in Ireland. Br J Soc Med 2016. [DOI: 10.1136/jech-2016-208064.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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OP55 Diabetes Nurse Specialist services in Ireland: A cross-sectional survey. Br J Soc Med 2016. [DOI: 10.1136/jech-2016-208064.55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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General practitioner views on the determinants of test ordering: a theory-based qualitative approach to the development of an intervention to improve immunoglobulin requests in primary care. Implement Sci 2016; 11:102. [PMID: 27435839 PMCID: PMC4952272 DOI: 10.1186/s13012-016-0465-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/02/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Research suggests that variation in laboratory requesting patterns may indicate unnecessary test use. Requesting patterns for serum immunoglobulins vary significantly between general practitioners (GPs). This study aims to explore GP's views on testing to identify the determinants of behaviour and recommend feasible intervention strategies for improving immunoglobulin test use in primary care. METHODS Qualitative semi-structured interviews were conducted with GPs requesting laboratory tests at Cork University Hospital or University Hospital Kerry in the South of Ireland. GPs were identified using a Health Service Executive laboratory list of GPs in the Cork-Kerry region. A random sample of GPs (stratified by GP requesting patterns) was generated from this list. GPs were purposively sampled based on the criteria of location (urban/rural); length of time qualified; and practice size (single-handed/group). Interviews were carried out between December 2014 and February 2015. Interviews were transcribed verbatim using NVivo 10 software and analysed using the framework analysis method. Emerging themes were mapped to the theoretical domains framework (TDF), which outlines 12 domains that can enable or inhibit behaviour change. The behaviour change wheel and behaviour change technique (BCT) taxonomy were then used to identify potential intervention strategies. RESULTS Sixteen GPs were interviewed (ten males and six females). Findings suggest that intervention strategies should specifically target the key barriers to effective test ordering, while considering the context of primary care practice. Seven domains from the TDF were perceived to influence immunoglobulin test ordering behaviours and were identified as 'mechanisms for change' (knowledge, environmental context and resources, social/professional role and identity, beliefs about capabilities, beliefs about consequences, memory, attention and decision-making processes and behavioural regulation). Using these TDF domains, seven BCTs emerged as feasible 'intervention content' for targeting GPs' ordering behaviour. These included instructions on how to effectively request the test (how to perform behaviour), information on GPs' use of the test (feedback on behaviour), information about patient consequences resulting from not doing the test (information about health consequences), laboratory/consultant-based advice/education (credible source), altering the test ordering form (restructuring the physical environment), providing guidelines (prompts/cues) and adding interpretive comments to the results (adding objects to the environment). These BCTs aligned to four intervention functions: education, persuasion, environmental restructuring and enablement. CONCLUSIONS This study has effectively applied behaviour change theory to identify feasible strategies for improving immunoglobulin test use in primary care using the TDF, 'behaviour change wheel' and BCT taxonomy. The identified BCTs will form the basis of a theory-based intervention to improve the use of immunoglobulin tests among GPs. Future research will involve the development and evaluation of this intervention.
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The prevalence of Type 2 diabetes and related complications in a nationally representative sample of adults aged 50 and over in the Republic of Ireland. Diabet Med 2016; 33:441-5. [PMID: 26112979 DOI: 10.1111/dme.12845] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/23/2015] [Indexed: 12/16/2022]
Abstract
AIM To investigate the prevalence of diagnosed Type 2 diabetes and its related complications in a nationally representative sample of older adults in the Republic of Ireland. METHODS Cross-sectional analysis of a population-based sample of adults aged ≥ 50 years from the first wave of The Irish Longitudinal Study on Ageing (TILDA), (2009-2011). Diagnosed Type 2 diabetes prevalence was estimated by self-report or the use of oral hypoglycaemic agents. The prevalence of microvascular and macrovascular complications was determined by self-report. RESULTS Diagnosed Type 2 diabetes prevalence was 8.4% [95% confidence interval (CI): 7.8-9.0%] and was higher among men [10.3% (95% CI: 9.4-11.2%)] than women [6.6% (95% CI: 5.9-7.5%)]; P ≤ 0.001. Among participants with diagnosed Type 2 diabetes, the overall prevalence of microvascular complications was 26.0% (95% CI: 22.4-30.0%) with no evidence of gender-specific differences (P = 0.7). The overall prevalence of macrovascular complications was 15.1% (95% CI: 12.2-18.4%) and was higher among men [17.8% (95% CI: 14.3-23.1%)] than women [11.4% (95% CI: 7.7-16.4%)]; P ≤ 0.001. CONCLUSIONS In the absence of a national diabetes register, these findings provide a robust estimate of the national prevalence of diagnosed Type 2 diabetes and level of complications among adults aged 50 years and over in Ireland.
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Trends in the incidence of visual impairment due to diabetic retinopathy in Ireland, 2004–2013. Eur J Public Health 2015. [DOI: 10.1093/eurpub/ckv171.069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Health workforce planning and service expansion during an economic crisis: A case study of the national breast screening programme in Ireland. Health Policy 2015; 119:1593-9. [PMID: 26421598 DOI: 10.1016/j.healthpol.2015.08.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 08/17/2015] [Accepted: 08/20/2015] [Indexed: 11/25/2022]
Abstract
This article aims to estimate the workforce and resource implications of the proposed age extension of the national breast screening programme, under the economic constraints of reduced health budgets and staffing levels in the Irish health system. Using a mixed method design, a purposive sample of 20 participants were interviewed and data were analysed thematically (June-September 2012). Quantitative data (programme-level activity data, screening activity, staffing levels and screening plans) were used to model potential workload and resource requirements. The analysis indicates that over 90% operational efficiency was achieved throughout the first six months of 2012. Accounting for maternity leave (10%) and sick leave (3.5%), 16.1 additional radiographers (whole time equivalent) would be required for the workload created by the age extension of the screening programme, at 90% operational efficiency. The results suggest that service expansion is possible with relatively minimal additional radiography resources if the efficiency of the skill mix and the use of equipment are improved. Investing in the appropriate skill mix should not be limited to clinical groups but should also include administrative staff to manage and support the service. Workload modelling may contribute to improved health workforce planning and service efficiency.
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OP34 Are older people with diabetes an at-risk group for falls? a cross-sectional analysis of community-dwelling adults ≥50 years in Ireland. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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PP21 Informing intervention design to improve diet and physical activity during pregnancy: a qualitative study of the attitudes and experiences of women and healthcare providers. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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OP26 Trends in the incidence of visual impairment due to diabetic retinopathy among adults in the republic of ireland, 2004–2013. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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OP83 Adverse childhood experience and health service utilisation: findings from a primary care-based study. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.82] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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PP50 A realist evaluation of the national clinical care programme for diabetes, a programme designed to engage and empower clinicians to lead change in the health system. Br J Soc Med 2015. [DOI: 10.1136/jech-2015-206256.147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Laminar airflow and the prevention of surgical site infection. More harm than good? Surgeon 2014; 13:52-8. [PMID: 25453272 DOI: 10.1016/j.surge.2014.10.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Revised: 09/24/2014] [Accepted: 10/12/2014] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Laminar airflow (LAF) systems are thought to minimise contamination of the surgical field with airborne microbes and thus to contribute to reducing surgical site infections (SSI). However recent publications have questioned whether LAF ventilation confers any significant benefit and may indeed be harmful. METHODS A detailed literature review was undertaken through www.Pubmed.com and Google scholar (http://scholar.google.com). Search terms used included "laminar flow". "laminar airflow", "surgical site infection prevention", "theatre ventilation" and "operating room ventilation", "orthopaedic theatre" and "ultra-clean ventilation". Peer-reviewed publications in the English language over the last 50 years were included, up to and including March 2014. RESULTS Laminar airflow systems are predominantly used in clean prosthetic implant surgery. Several studies have demonstrated decreased air bacterial contamination with LAF using bacterial sedimentation plates placed in key areas of the operating room. However, apart from the initial Medical Research Council study, there are few clinical studies demonstrating a convincing correlation between decreased SSI rates and LAF. Moreover, recent analyses suggest increased post-operative SSI rates. CONCLUSION It is premature to dispense with LAF as a measure to improve air quality in operating rooms where prosthetic joint surgery is being carried out. However, new multi-centre trials to assess this or the use of national prospective surveillance systems to explore other variables that might explain these findings such as poor operating room discipline are needed, to resolve this important surgical issue.
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PP47 Predictors of general medical services scheme coverage during a changing economic landscape in Ireland. Br J Soc Med 2014. [DOI: 10.1136/jech-2014-204726.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Surgical attire, practices and their perception in the prevention of surgical site infection. Surgeon 2013; 12:47-52. [PMID: 24268928 DOI: 10.1016/j.surge.2013.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 10/10/2013] [Accepted: 10/10/2013] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Clean surgical scrubs, surgical gowns and headgear are worn by operative teams to decrease bacterial contamination and lower surgical site infection (SSI) rates. METHODS A detailed review was undertaken of peer-reviewed publications and other sources of material in the English language over the last 50 years included. RESULTS Surgical scrubs should be clean and made of tightly woven material. Studies investigating single-use gowns and drapes versus reusable gowns report conflicting evidence. Double gloving may reduce SSI rates in procedures where no antibiotic prophylaxis was administered. Bacterial contamination of the operative field has been shown to be decreased by the wearing of surgical headgear by the operating team. CONCLUSIONS Further consideration and better trials are required to determine the impact of different theatre clothing on SSI rates.
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Patient perception of quality online: a double edged sword. Surgeon 2013; 12:1-2. [PMID: 24239400 DOI: 10.1016/j.surge.2013.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Assessing the sustainability of improved surgical infection prevention practices. Surgeon 2012; 10:301-2. [PMID: 22342068 DOI: 10.1016/j.surge.2012.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/04/2012] [Accepted: 01/04/2012] [Indexed: 10/28/2022]
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Preventing infection in general surgery: improvements through education of surgeons by surgeons. J Hosp Infect 2011; 78:312-6. [PMID: 21640433 DOI: 10.1016/j.jhin.2011.03.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Accepted: 03/21/2011] [Indexed: 11/28/2022]
Abstract
Surgical patients are at particular risk of healthcare-associated infection (HCAI) due to the presence of a surgical site leading to surgical site infection (SSI), and because of the need for intravascular access resulting in catheter-related bloodstream infection (CRBSI). A two-year initiative commenced with an initial audit of surgical practice; this was used to inform the development of a targeted educational initiative by surgeons specifically for surgical trainees. Parameters assessed during the initial audit and a further audit after the educational initiative were related to intra- and postoperative aspects of the prevention of SSIs, as well as care of peripheral venous catheters (PVCs) in surgical patients. The proportion of prophylactic antibiotics administered prior to incision across 360 operations increased from 30.0% to 59.1% (P<0.001). Surgical site dressings were observed in 234 patients, and a significant decrease was found in the percentage of dressings that were tampered with during the initial 48h after surgery (16.5% vs 6.2%, P=0.030). In total, 574 PVCs were assessed over the two-year period. Improvements were found in the proportion of unnecessary PVCs in situ (37.9% vs 24.4%, P<0.001), PVCs in situ for >72h (10.6% vs 3.1%, P<0.001) and PVCs covered with clean and intact dressings (87.3% vs 97.6%, P<0.001). Significant improvements in surgical practice were established for the prevention of SSI and CRBSI through a focused educational programme developed by and for surgeons. Potentially, other specific measures may also be warranted to achieve further improvements in infection prevention in surgical practice.
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A study of the factors influencing school-going students considering medical careers. Surgeon 2011; 9:191-4. [PMID: 21672658 DOI: 10.1016/j.surge.2010.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 09/09/2010] [Accepted: 09/09/2010] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Obtaining a place in an Irish medical school is extremely competitive, a situation mirrored in many other countries. We aimed to determine the factors influencing school students in deciding to study medicine in university. We further determined what level of interest exists in pursuing a surgical career after completion of medical school. METHODS The Royal College of Surgeons in Ireland hosts an annual "Introduction to Medicine" programme for senior school children. Attendees were surveyed using a Likert scale to examine the factors influencing the group in choosing to study medicine, and pursue surgery as their ultimate career choice. RESULTS A total of 128 completed the survey, giving a response rate of 100%. The opportunity to help others was most the most influential factors cited by students (97%). Males were significantly more likely to have an interest in a career in surgery rather than medicine (p = 0.003), and ranked "financial reward" (p = 0.036) as a more significant factors in influencing career choice than did females. CONCLUSIONS A clear understanding of these factors influencing our students in their career choices and a strategy of recruitment based on these is imperative in order to optimize recruitment of students most suited to working as doctors.
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The role of topical antibiotics used as prophylaxis in surgical site infection prevention. J Antimicrob Chemother 2011; 66:693-701. [PMID: 21393223 DOI: 10.1093/jac/dkr009] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Compared with systemic antibiotic therapy, the topical or local delivery of an antibiotic has many potential advantages. However, local antibiotics at the surgical site have received very limited approval in any of the surgical prophylaxis consensus guidelines that we are aware of. A review of the literature was carried out through searches of peer-reviewed publications in PubMed in the English language over a 30 year period between January 1980 and May 2010. Both retrospective and prospective studies were included, as well as meta-analyses. With regard to defining 'topical' or 'local' antibiotic application, the application of an antibiotic solution to the surgical site intraoperatively or immediately post-operatively was included. A number of surgical procedures have been shown to significantly benefit from perioperative topical prophylaxis, e.g. joint arthroplasty, cataract surgery and, possibly, breast augmentation. In obese patients undergoing abdominal surgery, topical surgical prophylaxis is also proven to be beneficial. The selective use of topical antibiotics as surgical prophylaxis is justified for specific procedures, such as joint arthroplasty, cataract surgery and, possibly, breast augmentation. In selective cases, such as obese patients undergoing abdominal surgery, topical surgical prophylaxis is also proven to be beneficial. Apart from these specific indications, the evidence for use of topical antibiotics in surgery is lacking in conclusive randomized controlled trials.
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Delayed ultraviolet erythema not suppressed by oral prednisolone: a randomized crossover study. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2009; 25:143-5. [PMID: 19438993 DOI: 10.1111/j.1600-0781.2009.00431.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND The anti-inflammatory potency of topical dermatological corticosteroids in suppressing ultraviolet (UV) erythema is routinely measured. No such model exists to assess the potency of systemically administered steroids. OBJECTIVE To determine whether or not suppression of delayed UV erythema by a systemic corticosteroid could provide a useful model for assessing the anti-inflammatory potency of systemic corticosteroids. METHODS We conducted a randomized, placebo-controlled, patient and assessor blinded, crossover study of oral prednisolone effects on the delayed UV-induced erythemal response in normal subjects. Six healthy volunteers were phototested with a xenon arc monochromator and then dosed with 30 mg of oral prednisolone or matching placebo daily for 4 days. Repeat phototesting was performed on the 4th day of dosing. The minimal erythema dose (MED) was assessed immediately after test UV doses were administered and 24 h later. After a 2-week washout period, the dosing and testing were repeated in a crossover fashion. RESULTS A suppression index (SI) [1/(baseline MED value divided by on prednisolone/placebo value)] allowed comparison of the degree of suppression on and off prednisolone. Oral prednisolone did not significantly suppress the threshold UV erythema response (MED). We may have missed small effects in this study and possibly a larger dose or a longer duration of corticosteroid would have had an effect. Possibly, assessment of corticosteroid potency in suppressing established UV erythema rather than on the development of threshold erythema would have yielded different results. CONCLUSION The threshold UV erythema suppression model assessed in this study could not distinguish between oral prednisolone and placebo. This UV-erythema suppression test system is not promising as a model to test the anti-inflammatory potency of systemic steroids.
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2 Neuro-Developmental Outcomes at 18 Months Corrected Age in Infants Weighing <1500 Grams Enrolled in a Randomized Trial of Agressive Versus Conservative Phototherapy. Paediatr Child Health 2004. [DOI: 10.1093/pch/9.suppl_a.13ab] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
Thalidomide was initially used as a sedative during pregnancy but was withdrawn from the market due to its teratogenic effects. In vitro studies have shown that thalidomide inhibits tumour necrosis factor alpha (TNF-alpha) mRNA expression and protein production by mitogen-stimulated macrophages and activated T cells. Even at the highest concentration (10-1 mM) tested, however, TNF-alpha levels are inhibited only partially and the mechanism of action is unknown. In the present investigations, we have examined the influence of thalidomide on nuclear levels of NF-kappa B in human peripheral blood mononuclear cells (PBMC) following activation with mitogen or phorbol myristate acetate (PMA)/ionophore. Dexamethasone was used as a positive control due to its well-characterised mechanism of action and NF-kappa B-mediated effects on TNF-alpha expression. PBMC from healthy human volunteers were stimulated optimally with phytohemagglutinin (PHA) or PMA/ionophore in the presence of 10(-1)-10(-5) mM thalidomide or dexamethasone, concentrations that displayed a range of inhibitory effects on TNF-alpha production. Cells were harvested at varying time points and nuclear extracts prepared. Nuclear levels of NF-kappa B were measured using electrophoretic mobility shift assays (EMSA) with a radiolabelled DNA probe specific for NF-kappa B. Results were analysed using optical densitometry. Nuclear levels of NF-kappa B were found to be unaffected by thalidomide at all concentrations tested, including concentrations (10(-1)-10(-3) mM) that exhibited significant inhibition of TNF-alpha protein and mRNA expression. In concurrent experiments, dexamethasone was found to reduce NF-kappa B expression in a dose-dependent manner with maximal inhibition at the highest dose tested (10(-1) mM). TNF-alpha gene expression is controlled by at least three separate transcription factors that are involved in binding to the promoter region. These observations suggest that thalidomide does not act directly on NF-kappa B and therefore inhibits TNF-alpha production through another independent mechanism.
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Selective down-regulation of T cell- and non-T cell-derived tumour necrosis factor alpha by thalidomide: comparisons with dexamethasone. Immunol Lett 1999; 68:325-32. [PMID: 10424439 DOI: 10.1016/s0165-2478(99)00055-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Both thalidomide and dexamethasone have been shown to inhibit the production of tumour necrosis factor alpha (TNF-alpha), but little is known of their cellular selectivity. Inhibition of monocyte TNF-alpha expression has been implicated in the clinical efficacy of thalidomide, and it has been suggested that the drug modulates only monocyte-derived cytokines. Given the importance of T lymphocyte responses in immunological disorders in which treatment with thalidomide has been successful, it is pertinent to study the effects of this drug on T cell-derived TNF-alpha. In the present investigations we have examined the influence of both thalidomide and dexamethasone on mitogen-induced elaboration of TNF-alpha by CD3+ peripheral blood mononuclear cells (PBMC) and the T cell line MOLT-4. PBMC from healthy human volunteers were stimulated optimally with phytohaemagglutinin (PHA) in the presence of varying concentrations of thalidomide or dexamethasone, and supernatants assayed for TNF-alpha and interleukin 2 (IL-2). Concurrently, PHA-stimulated PBMC were treated with 1 x 10(-1) mM thalidomide or dexamethasone and the cells fixed, permeabilised, stained with anti-CD3 and anti-TNF-alpha fluorescently labelled antibodies and analysed by flow cytometry. MOLT-4 cells were cultured in the presence or absence of the drugs following activation with phorbol myristate acetate (PMA)/ionophore, and supernatants analysed by enzyme-linked immunosorbent assay (ELISA) for cytokine expression. Thalidomide was found to inhibit PBMC-derived TNF-alpha, but not IL-2. In contrast, dexamethasone down-regulated both TNF-alpha and IL-2 in a dose-dependent manner. Thalidomide and dexamethasone both suppressed intracellular levels of TNF-alpha in CD3+ PBMC, reducing percentages of double positive staining cells by 28 and 52%, respectively, compared with controls. In addition, TNF-alpha production by CD3- PBMC was inhibited by 31% by thalidomide and by 47% by dexamethasone. In order to determine whether thalidomide was acting directly on T cells, or indirectly through effects on accessory cells, TNF-alpha production in the T cell line MOLT-4 was investigated. TNF-alpha secretion by PMA/ionophore activated MOLT-4 cells was reduced by 80% following thalidomide treatment and close to background levels following dexamethasone treatment. To verify that thalidomide was acting selectively to down-regulate TNF-alpha, IL-2 production by MOLT-4 cells was also measured and found to be unaffected by the drug. In contrast, dexamethasone reduced MOLT-4-derived IL-2 levels by 20%. These observations suggest that thalidomide, in addition to its known inhibitory effect on monocyte-derived TNF-alpha, is capable also of down-regulating T cell-derived TNF-alpha in a direct and selective manner. In addition, the inhibition of intracellular levels of TNF-alpha strengthens the evidence that the inhibitory effect of thalidomide is at the level of transcription and/or translation and does not reduce cellular TNF-alpha secretion. Such effects could explain the efficacy of thalidomide treatment in various immunological disorders where T cell activation plays an important role in the pathogenesis of the disease.
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Differential regulation by thalidomide and dexamethasone of cytokine expression in human peripheral blood mononuclear cells. IMMUNOPHARMACOLOGY 1998; 40:11-20. [PMID: 9776474 DOI: 10.1016/s0162-3109(98)00010-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Immunosuppressive drugs are used routinely to reduce the inappropriate production of cytokines in an immune response. Recent attention has focused on drugs that selectively inhibit specific cytokines. Both thalidomide and dexamethasone have been reported to exhibit immunomodulatory effects on cytokines in vitro. We wished to examine the effects of thalidomide and dexamethasone on the production of cytokines by peripheral blood mononuclear cells (PBMC), following mitogenic stimulation, at the level of both secreted product and mRNA production. PBMC from healthy human volunteers were stimulated optimally with phytohaemagglutinin (PHA) in the presence of varying concentrations of thalidomide and dexamethasone using dimethyl sulphoxide (DMSO) as the solvent. Analysis of supernatants by enzyme-linked immunosorbent assay (ELISA) showed that thalidomide caused a dose-dependent inhibition of the pro-inflammatory cytokines interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-alpha), maximally reducing production by 20 (P < 0.05) and 30% (P < 0.01), respectively, compared with controls. However, thalidomide did not affect either proliferation or the production of interleukin 2 (IL-2), interleukin 4 (IL-4) or interleukin 10 (IL-10). A slight bell shaped inhibition of interferon gamma (IFN-gamma) was seen which was statistically significant (P < 0.05). In contrast, dexamethasone inhibited markedly the expression of all cytokines tested (IL-2, IL-4, IL-6, IL-10, IFN-gamma and TNF-alpha) in dose-dependent fashion, reducing levels to near to background. Reverse transcription-polymerase chain reaction (RT-PCR) analyses showed that thalidomide inhibited selectively the expression of TNF-alpha and IL-6 mRNA, whereas dexamethasone inhibited mRNA levels of all cytokines examined. The data indicate that dexamethasone is a broad range immunosuppressant inhibiting all cytokines tested in a dose-dependent manner at the level of both secreted product and mRNA. Conversely, thalidomide selectively inhibits the production of IL-6 and TNF-alpha. Due to their markedly different effects on cytokine production, and the fact that both drugs act at the level of transcription, we believe they influence separate pathways involved in cytokine gene regulation.
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Thalidomide and derivatives: immunological investigations of tumour necrosis factor-alpha (TNF-alpha) inhibition suggest drugs capable of selective gene regulation. Clin Exp Immunol 1997; 110:151-4. [PMID: 9367395 PMCID: PMC2265499 DOI: 10.1111/j.1365-2249.1997.tb08310.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/1997] [Indexed: 02/05/2023] Open
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To bee or not to be? T-cell responses to bee venom PLA2 in relation to anaphylaxis and immunotherapy. Clin Exp Allergy 1997; 27:986-90. [PMID: 9678827 DOI: 10.1111/j.1365-2222.1997.tb01245.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bee venom immunotherapy induces a shift in cytokine responses from a TH-2 to a TH-1 dominant pattern: comparison of rush and conventional immunotherapy. Clin Exp Allergy 1995; 25:828-38. [PMID: 8564721 DOI: 10.1111/j.1365-2222.1995.tb00025.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The mechanism of immunotherapy is unclear. Allergic disease is known to involve enhanced TH-2 cytokine responses to allergen. OBJECTIVE In order to investigate the mechanisms of immunotherapy, we have examined changes in cytokine secretion before (13 patients) and during (nine patients) both rush and conventional venom immunotherapy (VIT) in bee venom allergic patients. METHODS Peripheral blood mononuclear cells were stimulated in vitro with bee venom, non-specific antigen or mitogen and secretion of IL-4 (TH-2) and IFN gamma (TH-1) over the culture period measured. RESULTS Untreated patients had TH-2 responses to venom and TH-1 responses to antigen and strong proliferative responses to venom. Controls showed no response (proliferation or cytokines) to venom and the normal TH-1 response to antigen. VIT resulted in marked changes in cytokine secretion to venom, with reduction of the abnormal TH-2 response and induction of a TH-1 response. The pattern differed in rush and conventional VIT. One day after rush VIT there was a significant fall in IL-4 secretion (P < 0.01), which rose by 3 weeks then declined. In conventional VIT there was a gradual reduction of IL-4 production significant after 2 months and undetectable by 6 months. IFN gamma secretion was induced by VIT. Proliferative responses mirrored the IL-4 changes. One day after rush VIT there was a loss of T cells, monocytes and NK cells from peripheral blood. CONCLUSION This study shows that immunotherapy shifted cytokine responses to allergen from a TH-2 to a TH-1 dominant pattern, suggesting direct effects on T cells. How these cytokine changes relate to clinical desensitization is not clear. In the longer term they would result in an isotype switch from IgE to IgG. Early changes in cytokine or chemokine production might downregulate mast cell or basophil reactivity and explain the rapid desensitization in rush VIT.
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The immunosuppressive drug thalidomide induces T helper cell type 2 (Th2) and concomitantly inhibits Th1 cytokine production in mitogen- and antigen-stimulated human peripheral blood mononuclear cell cultures. Clin Exp Immunol 1995; 99:160-7. [PMID: 7851006 PMCID: PMC1534314 DOI: 10.1111/j.1365-2249.1995.tb05527.x] [Citation(s) in RCA: 210] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Thalidomide is an effective immunomodulatory drug in man, but its mechanism of action remains unclear. We hypothesized that, in addition to its reported inhibitory effects on production of monocyte-derived tumour necrosis factor-alpha (TNF-alpha), thalidomide might be effective at the level of Th immunoregulation. In a comparative study with the immunosuppressant cyclosporin A, we have demonstrated a potent and specific effect of thalidomide on cytokine production relating to the distinct Th1 and Th2 subsets. It induced and enhanced the production of IL-4 and IL-5 and, at the same dose (1000 ng/ml), significantly inhibited interferon-gamma (IFN-gamma) production in phytohaemagglutinin (PHA)-stimulated human peripheral blood mononuclear cell (PBMC) cultures. Stimulation of PBMC with recall antigen (streptokinase:streptodornase (SKSD)) at 144 h in the absence of thalidomide resulted in a predominantly Th1 response, with the production of IFN-gamma and IL-2. Thalidomide switched this response from a Th1 to a Th2 type. The effect was most pronounced at 1000 ng/ml thalidomide, where inhibition of IFN-gamma and enhancement of IL-4 production was maximal. In unstimulated cultures thalidomide alone induced IL-4 production. Cyclosporin A, in contrast, inhibited both Th1 and Th2 cytokine production by PHA-stimulated PBMC. Time course data from thalidomide-treated cultures revealed that the augmented IL-4 production diminished as the culture time increased, whereas IFN-gamma production was significantly increased. This response might be due to activation-induced apoptosis of Th2 cells or the induction of Th2 cell anergy, in the continued presence of stimulating agents, with the emergence of IFN-gamma-secreting Th1 cells when Th2 antagonism declines. The effects of thalidomide and related compounds may enhance our understanding of the mechanisms of T helper cell selection, offer the possibility of controlled therapeutic switching between Th1 and Th2 responses, and may lead to a rational approach for the treatment of some T cell-mediated immunological disorders.
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The profiles of interleukin (IL)-2, IL-6, and interferon-gamma production by peripheral blood mononuclear cells from house-dust-mite-allergic patients: a role for IL-6 in allergic disease. Allergy 1994; 49:751-9. [PMID: 7695065 DOI: 10.1111/j.1398-9995.1994.tb02098.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have developed a model to measure cytokine production by peripheral blood mononuclear cells (PBMC) in vitro. In this report, we examine the production of interleukin-2 (IL-2), IL-6, and interferon-gamma (IFN-gamma) by PBMC of house-dust-mite (Dermatophagoides pteronyssinus)-allergic subjects. When stimulated with specific allergen (D. pteronyssinus), PBMC of patients produced significant levels of IL-2 and high levels of IL-6, but little or no IFN-gamma. Nonatopic control PBMC also produced IL-6, although at lower levels, but no IL-2 or IFN-gamma. A ubiquitous antigen, streptokinase/streptodornase (SKSD), induced high levels of IL-2 in patients, but only low levels of IFN-gamma and IL-6. Nonatopic controls produced similar levels of IL-2 and IL-6, but high levels of IFN-gamma to SKSD. IL-2 and IFN-gamma levels induced by the T-cell mitogen phytohaemagglutinin (PHA) were similar in patient and control groups, but IL-6 levels were significantly lower in the patients. IgE synthesis in vitro was shown only in atopic PBMC cultures stimulated with specific allergen. The major points can be summarized as 1) IL-2 production by atopic patients in response to allergen; 2) IL-6 production to allergen by both atopic and nonatopic patients, but significantly increased in atopic patients; and 3) defective IFN-gamma production by atopic patients to both allergen and antigen.(ABSTRACT TRUNCATED AT 250 WORDS)
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