56 research outputs found
An ex vivo model using human osteoarthritic cartilage demonstrates the release of bioactive insulin-like growth factor-1 from a collagen-glycosaminoglycan scaffold.
Biomimetic scaffolds hold great promise for therapeutic repair of cartilage, but although most scaffolds are tested with cells in vitro, there are very few ex vivo models (EVMs) where adult cartilage and scaffolds are co-cultured to optimize their interaction prior to in vivo studies. This study describes a simple, non-compressive method that is applicable to mammalian or human cartilage and provides a reasonable throughput of samples. Rings of full-depth articular cartilage slices were derived from human donors undergoing knee replacement for osteoarthritis and a 3 mm core of a collagen/glycosaminoglycan biomimetic scaffold (Tigenix, UK) inserted to create the EVM. Adult osteoarthritis chondrocytes were seeded into the scaffold and cultures maintained for up to 30 days. Ex vivo models were stable throughout experiments, and cells remained viable. Chondrocytes seeded into the EVM attached throughout the scaffold and in contact with the cartilage explants. Cell migration and deposition of extracellular matrix proteins in the scaffold was enhanced by growth factors particularly if the scaffold was preloaded with growth factors. This study demonstrates that the EVM represents a suitable model that has potential for testing a range of therapeutic parameters such as numbers/types of cell, growth factors or therapeutic drugs before progressing to costly pre-clinical trials.The authors would like to kindly acknowledge funding from the EPSRC and Tigenix Ltd
(LM), Technology Strategy Board and Tigenix Ltd (JW) and the NIHR (DH).This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/cbf.3112
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Understanding the influences on successful quality improvement in emergency general surgery: learning from the RCS Chole-QuIC project
Abstract: Background: Acute gallstone disease is the highest volume Emergency General Surgical presentation in the UK. Recent data indicate wide variations in the quality of care provided across the country, with national guidance for care delivery not implemented in most UK hospitals. Against this backdrop, the Royal College of Surgeons of England set up a 13-hospital quality improvement collaborative (Chole-QuIC) to support clinical teams to reduce time to surgery for patients with acute gallstone disease requiring emergency cholecystectomy. Methods: Prospective, mixed-methods process evaluation to answer the following: (1) how was the collaborative delivered by the faculty and received, understood and enacted by the participants; (2) what influenced teams’ ability to improve care for patients requiring emergency cholecystectomy? We collected and analysed a range of data including field notes, ethnographic observations of meetings, and project documentation. Analysis was based on the framework approach, informed by Normalisation Process Theory, and involved the creation of comparative case studies based on hospital performance during the project. Results: Chole-QuIC was delivered as planned and was well received and understood by participants. Four hospitals were identified as highly successful, based upon a substantial increase in the number of patients having surgery in line with national guidance. Conversely, four hospitals were identified as challenged, achieving no significant improvement. The comparative analysis indicate that six inter-related influences appeared most associated with improvement: (1) achieving clarity of purpose amongst site leads and key stakeholders; (2) capacity to lead and effective project support; (3) ideas to action; (4) learning from own and others’ experience; (5) creating additional capacity to do emergency cholecystectomies; and (6) coordinating/managing the patient pathway. Conclusion: Collaborative-based quality improvement is a viable strategy for emergency surgery but success requires the deployment of effective clinical strategies in conjunction with improvement strategies. In particular, achieving clarity of purpose about proposed changes amongst key stakeholders was a vital precursor to improvement, enabling the creation of additional surgical capacity and new pathways to be implemented effectively. Protected time, testing ideas, and the ability to learn quickly from data and experience were associated with greater impact within this cohort
A high-resolution melt curve toolkit to identify lineage-defining SARS-CoV-2 mutations
The emergence of severe acute respiratory syndrome 2 (SARS-CoV-2) variants of concern (VOCs), with mutations linked to increased transmissibility, vaccine escape and virulence, has necessitated the widespread genomic surveillance of SARS-CoV-2. This has placed a strain on global sequencing capacity, especially in areas lacking the resources for large scale sequencing activities. Here we have developed three separate multiplex high-resolution melting assays to enable the identification of Alpha, Beta, Delta and Omicron VOCs. The assays were evaluated against whole genome sequencing on upper-respiratory swab samples collected during the Alpha, Delta and Omicron [BA.1] waves of the UK pandemic. The sensitivities of the eight individual primer sets were all 100%, and specificity ranged from 94.6 to 100%. The multiplex HRM assays have potential as a tool for high throughput surveillance of SARS-CoV-2 VOCs, particularly in areas with limited genomics facilities
Effectiveness of a quality improvement collaborative in reducing time to surgery for patients requiring emergency cholecystectomy.
BACKGROUND: Acute gallstone disease is a high-volume emergency general surgery presentation with wide variations in the quality of care provided across the UK. This controlled cohort evaluation assessed whether participation in a quality improvement collaborative approach reduced time to surgery for patients with acute gallstone disease to fewer than 8 days from presentation, in line with national guidance. METHODS: Patients admitted to hospital with acute biliary conditions in England and Wales between 1 April 2014 and 31 December 2017 were identified from Hospital Episode Statistics data. Time series of quarterly activity were produced for the Cholecystectomy Quality Improvement Collaborative (Chole-QuIC) and all other acute National Health Service hospitals (control group). A negative binomial regression model was used to compare the proportion of patients having surgery within 8 days in the baseline and intervention periods. RESULTS: Of 13 sites invited to join Chole-QuIC, 12 participated throughout the collaborative, which ran from October 2016 to January 2018. Of 7944 admissions, 1160 patients had a cholecystectomy within 8 days of admission, a significant improvement (P < 0·050) from baseline performance. This represented a relative change of 1·56 (95 per cent c.i. 1·38 to 1·75), compared with 1·08 for the control group. At the individual site level, eight of the 12 Chole-QuIC sites showed a significant improvement (P < 0·050), with four sites increasing their 8-day surgery rate to over 20 per cent of all emergency admissions, well above the mean of 15·3 per cent for control hospitals. CONCLUSION: A surgeon-led quality improvement collaborative approach improved care for patients requiring emergency cholecystectomy
Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial
Background
Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects.
Methods
FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762.
Findings
Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months.
Interpretation
Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function.
Funding
UK Stroke Association and NIHR Health Technology Assessment Programme
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