oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 3 )

2019 ( 250 )

2018 ( 429 )

2017 ( 441 )

Custom range...

Search Results: 1 - 10 of 234689 matches for " Matthew L Costa "
All listed articles are free for downloading (OA Articles)
Page 1 /234689
Display every page Item
Warwick Hip Trauma Study: a randomised clinical trial comparing interventions to improve outcomes in internally fixed intracapsular fractures of the proximal femur. Protocol for The WHiT Study
Xavier Griffin, Nick Parsons, Juul Achten, Matthew L Costa
BMC Musculoskeletal Disorders , 2010, DOI: 10.1186/1471-2474-11-184
Abstract: We have planned a three arm, single centre, standard-of-care controlled, double blinded, pragmatic, randomised clinical trial. The trial will include a standard two-way comparison between platelet-rich plasma and standard-of-care fixation versus standard-of-care fixation alone. In addition there will be a subsidiary pilot arm testing a fixed-angle screw and plate fixation system.Current Controlled Trials ISRCTN49197425Proximal femoral fractures are one of the greatest challenges facing the medical community. In 1990, a global incidence of 1.31 million was reported and was associated with 740,000 deaths [1]. Proximal femoral fractures constitute a heavy socioeconomic burden worldwide. The cost of this clinical problem is estimated at 1.75 million disability adjusted life years lost, 1.4% of the total healthcare burden in established market economies [1].Proximal femoral fractures can be subdivided into intra and extracapsular fractures. Approximately half of all proximal femoral fractures are intracapsular. These fractures are at risk of healing complications as the blood supply to the femoral head may be compromised by the fracture. There are two operative strategies in the management of intracapsular fractures of the proximal femur: internal fixation and hip arthroplasty.Arthroplasty surgery eliminates the risk of fixation failure as the femoral head is replaced. However, it is a major operation with very significant complications of its own including infection, dislocation and periprosthetic fracture. The most common form of arthroplasty in this group of patients is hemiarthroplasty, where the head of the femur is replaced but the acetabulum is left intact, but this procedure is associated with an approximately 20% risk of late acetabular wear leading to arthritic changes and the potential need for further surgery [2]. Internal fixation has the key advantage of preserving the patients' own bone and cartilage. It is also a quicker operation requiring a much smaller
An evaluation of the quality of statistical design and analysis of published medical research: results from a systematic survey of general orthopaedic journals
Nick R Parsons, Charlotte L Price, Richard Hiskens, Juul Achten, Matthew L Costa
BMC Medical Research Methodology , 2012, DOI: 10.1186/1471-2288-12-60
Abstract: A detailed statistical survey sampled 100 representative orthopaedic papers using a validated questionnaire that assessed the quality of the trial design and statistical analysis methods.The survey found evidence of failings in study design, statistical methodology and presentation of the results. Overall, in 17% (95% confidence interval; 10–26%) of the studies investigated the conclusions were not clearly justified by the results, in 39% (30–49%) of studies a different analysis should have been undertaken and in 17% (10–26%) a different analysis could have made a difference to the overall conclusions.It is only by an improved dialogue between statistician, clinician, reviewer and journal editor that the failings in design methodology and analysis highlighted by this survey can be addressed.
The comprehensive cohort model in a pilot trial in orthopaedic trauma
Rebecca S Kearney, Juul Achten, Nick R Parsons, Matthew L Costa
BMC Medical Research Methodology , 2011, DOI: 10.1186/1471-2288-11-39
Abstract: Pragmatic randomised controlled trial and comprehensive cohort study within a level 1 trauma centre. Twenty randomised participants (10 operative and 10 non-operative) and 29 preference participants (3 operative and 26 non-operative). The ge range was 22-72 years and 37 of the 52 patients were men. All participants had an acute rupture of their Achilles tendon and no other injuries. All of the patients in the operative group had a simple end-to-end repair of the tendon with no augmentation. Both groups then followed the same eight-week immediate weight-bearing rehabilitation programme using an off-the-shelf orthotic. The disability rating index (DRI; primary outcome), EQ-5D, Achilles Total Rupture Score and complications were assessed ed at two weeks, six weeks, three months, six months and nine months after initial injury.At nine months, there was no significant difference in DRI between patients randomised to operative or non-operative management. There was no difference in DRI between the randomised group and the parallel patient preference group. The use of a comprehensive cohort of patients did not provide useful additional information as to the treatment effect size because the majority of patients chose non-operative management.Recruitment to clinical trials that compare operative and non-operative interventions is notoriously difficult; especially within the trauma setting. Including a parallel patient preference group to create a comprehensive cohort of patients has been suggested as a way of increasing the power of such trials. In our study, the comprehensive cohort model doubled the number of patients involved in the study. However, a strong preference for non-operative treatment meant that the increased number of patients did not significantly increase the ability of the trial to detect a difference between the two interventions.ISRCTN: ISRCTN29053307Randomised controlled trials are accepted as the 'gold standard' in trial design for evaluating the effec
The Achilles tendon total rupture score: a study of responsiveness, internal consistency and convergent validity on patients with acute Achilles tendon ruptures
Rebecca S Kearney, Juul Achten, Sarah E Lamb, Nicholas Parsons, Matthew L Costa
Health and Quality of Life Outcomes , 2012, DOI: 10.1186/1477-7525-10-24
Abstract: Consequently the purpose of this study was to evaluate internal consistency, convergent validity and responsiveness of this newly developed patient reported outcome measure within patients who have sustained an isolated acute Achilles tendon rupture.Sixty-four eligible patients with an acute rupture of their Achilles tendon completed the Achilles tendon Total Rupture Score alongside two further patient reported outcome measures (Disability Rating Index and EQ 5D). These were completed at baseline, six weeks, three months, six months and nine months post injury. The Achilles tendon Total Rupture Score was evaluated for internal consistency, using Cronbach's alpha, convergent validity, through correlation analysis and responsiveness, by analysing floor and ceiling effects and calculating its relative efficiency in comparison to the Disability Rating Index and EQ 5D scores.The Achilles tendon Total Rupture Score demonstrated high internal consistency (Cronbachs alpha > 0.8) and correlated significantly (p < 0.001) with the Disability Rating Index at five time points (pre-injury, six weeks, three, six and nine months) with correlation coefficients between -0.5 and -0.9. However, the confidence intervals were wide. Furthermore, the ability of the new score to detect clinically important changes over time (responsiveness) was shown to be greater than the Disability Rating Index and EQ 5D.A universally accepted outcome measure is imperative to allow comparisons to be made across practice. This is the first study to evaluate aspects of validity of this newly developed outcome measure, outside of the developing centre. The ATRS demonstrated high internal consistency and responsiveness, with limited convergent validity. This research provides further support for the use of this outcome measure, however further research is required to advocate its universal use in patients with acute Achilles tendon ruptures. Such areas include inter-rater reliability and research to determine
A randomised controlled trial of total hip arthroplasty versus resurfacing arthroplasty in the treatment of young patients with arthritis of the hip joint
Juul Achten, Nick R Parsons, Richard P Edlin, Damian R Griffin, Matthew L Costa
BMC Musculoskeletal Disorders , 2010, DOI: 10.1186/1471-2474-11-8
Abstract: All patients medically fit for surgery and deemed suitable for a resurfacing arthroplasty are eligible to take part in this study. A randomisation sequence will be produced and administered independently. After consenting, all patients will be clinically reviewed and hip function, quality of life and physical activity level will be assessed through questionnaires. The allocated surgery will then be performed with the preferred technique of the surgeon. Six weeks post-operation hip function will be assessed and complications recorded. Three, six and 12 months post-operation hip function, quality of life and physical activity level will be assessed. Additional information about patients' out-of-pocket expenses will also be collected.Current Controlled Trials ISRCTN33354155UKCLRN portfolio ID 4093Hip arthroplasty is a procedure which has been performed by orthopaedic surgeons for decades, with improvements to the procedure and the implants being made almost continuously over that time. For older patients, several designs of Total Hip Arthroplasty (THA) have shown excellent results in terms of both function and value for money [1]. However, in younger more active patients, there is an approximate 50% failure rate at 25 years for traditional implants [2]. Modern THA designs with hard bearing surfaces may improve upon these results [3], but long-term evidence is lacking. The early results of Resurfacing Arthroplasty (RSA), a new technique where the proximal femoral anatomy is preserved, suggest a 98% survival at five years [4]; which is as good as any of the existing THA's [1]. However, no long-term data exists. In a recent review of the literature on RSA it was concluded that although the short-term functional results appear promising, some potential early disadvantages were identified; including risk of femoral neck fracture, avascular necrosis of the head of the femur and acetabular bone stock sacrifice [5].At present, only a few randomised trials have been performed c
UK DRAFFT - A randomised controlled trial of percutaneous fixation with kirschner wires versus volar locking-plate fixation in the treatment of adult patients with a dorsally displaced fracture of the distal radius
Matthew L Costa, Juul Achten, Nick R Parsons, Amar Rangan, Richard P Edlin, Jaclyn Brown, Sarah E Lamb
BMC Musculoskeletal Disorders , 2011, DOI: 10.1186/1471-2474-12-201
Abstract: All adult patients with an acute, dorsally-displaced fracture of the distal radius, requiring operative fixation are potentially eligible to take part in this study. A total of 390 consenting patients will be randomly allocated to either K-wire fixation or locking-plate fixation. The surgery will be performed in trauma units across the UK using the preferred technique of the treating surgeon. Data regarding wrist function, quality of life, complications and costs will be collected at six weeks and three, six and twelve months following the injury. The primary outcome measure will be wrist function with a parallel economic analysis.This pragmatic, multi-centre trial is due to deliver results in December 2013.Current Controlled Trials ISRCTN31379280UKCRN portfolio ID 8956Fractures of the distal radius are extremely common injuries. In the Western World, 6% of women will have sustained such a fracture by the age of 80 and 9% by the age of 90 [1]. The optimal management of fractures of the distal radius in adults remains controversial. There is a bimodal distribution in terms of age. Younger patients frequently sustain complicated, high-energy injuries involving the wrist joint. However, fractures of the distal radius are also common in older patients who are more likely to sustain low-energy fractures, often related to osteoporosis [2] This study is designed to address both groups of patients as the key management issues pertain to all patients with a fracture of the distal radius.In general, fractures of the distal radius are treated non-operatively if the bone fragments are undisplaced or the fragments can be held in anatomical alignment (reduction) by a plaster cast or orthotic. However, if this is not possible then operative fixation is required. This carries inherent risks for the patient and considerable cost implications for the NHS; much of this cost is related to the choice of fixation [3].There are several operative options but the two most common in the UK,
Atomistic Simulations of Formation of Elementary Zr-I Systems  [PDF]
Christopher D. Taylor, Matthew L. Rossi
Open Journal of Physical Chemistry (OJPC) , 2011, DOI: 10.4236/ojpc.2011.13014
Abstract: We report results of simulations on the formation of simple zirconium iodide molecules. Previous work by Wimmer et al. [1] explored the relationship between iodine and a zirconium surface. We investigate the reaction schemes through atomistic simulations to better understand the nature of Zr-I interactions through isolated molecules. The computed energy values of varying Zr-I systems suggests a strong binding mechanism between zirconium and iodine, and offer predictions of likely reaction products. The computed results predict condensation of volatile ZrI4 with ZrI2 to form Zr2I6
Inhibiting AKT Phosphorylation Employing Non-Cytotoxic Anthraquinones Ameliorates TH2 Mediated Allergic Airways Disease and Rhinovirus Exacerbation
Caio Cesar de Souza Alves, Adam Collison, Luke Hatchwell, Maximilian Plank, Matthew Morten, Paul S. Foster, Sebastian L. Johnston, Cristiane Fran?a da Costa, Mauro Vieira de Almeida, Henrique Couto Teixeira, Ana Paula Ferreira, Joerg Mattes
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079565
Abstract: Background Severe asthma is associated with T helper (TH) 2 and 17 cell activation, airway neutrophilia and phosphoinositide-3-kinase (PI3K) activation. Asthma exacerbations are commonly caused by rhinovirus (RV) and also associated with PI3K-driven inflammation. Anthraquinone derivatives have been shown to reduce PI3K-mediated AKT phosphorylation in-vitro. Objective To determine the anti-inflammatory potential of anthraquinones in-vivo. Methods BALB/c mice were sensitized and challenged with crude house dust mite extract to induce allergic airways disease and treated with mitoxantrone and a novel non-cytotoxic anthraquinone derivative. Allergic mice were also infected with RV1B to induce an exacerbation. Results Anthraquinone treatment reduced AKT phosphorylation, hypoxia-inducible factor-1α and vascular endothelial growth factor expression, and ameliorated allergen- and RV-induced airways hyprereactivity, neutrophilic and eosinophilic inflammation, cytokine/chemokine expression, mucus hypersecretion, and expression of TH2 proteins in the airways. Anthraquinones also boosted type 1 interferon responses and limited RV replication in the lung. Conclusion Non-cytotoxic anthraquinone derivatives may be of therapeutic benefit for the treatment of severe and RV-induced asthma by blocking pro-inflammatory pathways regulated by PI3K/AKT.
Antigen Cross-Priming of Cell-Associated Proteins is Enhanced by Macroautophagy within the Antigen Donor Cell
Matthew L. Albert
Frontiers in Immunology , 2012, DOI: 10.3389/fimmu.2012.00061
Abstract: Phagocytosis of dying cells constitutes an important mechanism of antigen capture for the cross-priming of CD8+ T cells. This process has been shown to be critical for achieving tumor and viral immunity. While most studies have focused on the mechanisms inherent in the dendritic cell that account for exogenous antigen accessing MHC I, several recent reports have highlighted the important contribution made by the antigen donor cell. Specifically, the cell stress and cell death pathways that precede antigen transfer are now known to impact cross-presentation and cross-priming. Herein, we review the current literature regarding a role for macroautophagy within the antigen donor cell. Further examination of this point of immune regulation is warranted and may contribute to a better understanding of how to optimize immunotherapy for treatment of cancer and chronic infectious disease.
Bilingual Picture–Word Studies Constrain Theories of Lexical Selection
Matthew L. Hall
Frontiers in Psychology , 2011, DOI: 10.3389/fpsyg.2011.00381
Abstract: Whether lexical selection is by competition is the subject of current debate in studies of monolingual language production. Here, I consider whether extant data from bilinguals can inform this debate. In bilinguals, theories that accept the notion of lexical selection by competition are divided between those positing competition among all lexical nodes vs. those that restrict competition to nodes in the target language only. An alternative view rejects selection by competition altogether, putting the locus of selection in a phonological output buffer, where some potential responses are easier to exclude than others. These theories make contrasting predictions about how quickly bilinguals should name pictures when non-target responses are activated. In Part 1, I establish the empirical facts for which any successful theory must account. In Part 2, I evaluate how well each theory accounts for the data. I argue that the data do not support theories that reject lexical selection by competition, and that although theories where competition for selection is restricted to the target language can be altered to fit the data, doing so would fundamentally undermine the distinctness of their position. Theories where selection is by competition throughout both target and non-target language lexicons must also be modified to account for the data, but these modifications are relatively peripheral to the theoretical impetus of the model. Throughout, I identify areas where our empirical facts are sparse, weak, or absent, and propose additional experiments that should help to further establish how lexical selection works, in both monolinguals and bilinguals.
Page 1 /234689
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.