1,118 research outputs found
THE ROLE OF PREVIOUS ANTERIOR CRUCIATE LIGAMENT INJURY ON THE VARIABILITY OF JOINT KINEMATICS AND COORDINATION DURING A MATCH SPECIFIC LAND-CUT TASK
This study compared the movement and coordination variability of the previously injured leg of ACL injured subjects (ACLr, n=9), against their non-injured leg and a control (nACL, n=9) leg. The variability of lower limb joint angles and couplings were calculated during a land-cut task (n=20). The previously injured leg had less variability than the noninjured leg in the knee rotation–knee abd-adduction coupling, and more variability than the nACL leg in frontal and transverse knee joint angles and hip rotation–knee abdadduction coupling. Reduced coordination variability could produce a more repetitive loading pattern linked to cartilage degeneration. Increased movement and coordination variability may stem from proprioceptive deficits on the previously injured leg and decrease the ability to adapt to perturbations
Lower limb coordination during a land-cut task following anterior cruciate ligament reconstruction and rehabilitation
This study compared the lower limb coordination of the previously injured leg of ACL injured participantsparticipants (ACLr, n=18), against their non-injured leg and a control (nACL, n=18) leg. The lower limb joint and segment couplings were calculated during maximal drop-jump land and unanticipated cutting task. Differences between the previously injured and nACL control leg were present in all but one of the lower limb joint and segment couplings. Differences between the previously injured and nACL control leg were present in the hip rotation - knee abduction adduction, and knee rotation knee abduction adduction couplings. The hip and thigh were the main areas where differences were reported. Altered proximal neuromuscular function may be the origin of these altered coordination patterns
Repeatability of quantitative18F-FLT uptake measurements in solid tumors: an individual patient data multi-center meta-analysis
INTRODUCTION: 3'-deoxy-3'-[18F]fluorothymidine (18F-FLT) positron emission tomography (PET) provides a non-invasive method to assess cellular proliferation and response to antitumor therapy. Quantitative18F-FLT uptake metrics are being used for evaluation of proliferative response in investigational setting, however multi-center repeatability needs to be established. The aim of this study was to determine the repeatability of18F-FLT tumor uptake metrics by re-analyzing individual patient data from previously published reports using the same tumor segmentation method and repeatability metrics across cohorts. METHODS: A systematic search in PubMed, EMBASE.com and the Cochrane Library from inception-October 2016 yielded five18F-FLT repeatability cohorts in solid tumors.18F-FLT avid lesions were delineated using a 50% isocontour adapted for local background on test and retest scans. SUVmax, SUVmean, SUVpeak, proliferative volume and total lesion uptake (TLU) were calculated. Repeatability was assessed using the repeatability coefficient (RC = 1.96 × SD of test-retest differences), linear regression analysis, and the intra-class correlation coefficient (ICC). The impact of different lesion selection criteria was also evaluated. RESULTS: Images from four cohorts containing 30 patients with 52 lesions were obtained and analyzed (ten in breast cancer, nine in head and neck squamous cell carcinoma, and 33 in non-small cell lung cancer patients). A good correlation was found between test-retest data for all18F-FLT uptake metrics (R2 ≥ 0.93; ICC ≥ 0.96). Best repeatability was found for SUVpeak(RC: 23.1%), without significant differences in RC between different SUV metrics. Repeatability of proliferative volume (RC: 36.0%) and TLU (RC: 36.4%) was worse than SUV. Lesion selection methods based on SUVmax ≥ 4.0 improved the repeatability of volumetric metrics (RC: 26-28%), but did not affect the repeatability of SUV metrics. CONCLUSIONS: In multi-center studies, differences ≥ 25% in18F-FLT SUV metrics likely represent a true change in tumor uptake. Larger differences are required for FLT metrics comprising volume estimates when no lesion selection criteria are applied
The burden of dental care in Amelogenesis Imperfecta paediatric patients in the UK NHS: a retrospective, multi-centred analysis
PURPOSE: The burden of dental care in Amelogenesis Imperfecta (AI) has not been well described. This condition results in weak, discoloured and often sensitive teeth. Specialist paediatric care is available for AI patients in the UK, but treatment protocols and care provided are inconsistent. The aim of this study was therefore to analyse the provision of treatment and burden of care for children and families with AI across four Paediatric Dentistry centres in the UK. METHODS: A retrospective evaluation of AI patient clinical records across four UK consultant-led Paediatric Dentistry centres was completed. Frequency and duration of care were recorded along with treatment and experience of inhalation sedation, local and general anaesthetic. RESULTS: In total, 138 records were available for analysis. The average patient age at first referral was 7.7 years (range 1-16 years) and families travelled an average 21.8 miles per appointment (range 0.2-286 miles). Patients attended on average 4.5 appointments per year for 5.8 years. In total, 65.2% had experience of local anaesthetic, 27.5% inhalation sedation and 31.9% general anaesthetic. Dental treatment including restorations and extractions were commonly required on multiple teeth per patient. CONCLUSION: AI carries a high burden of specialist dental care to patients and families. Specialist centres are required to provide longitudinal, comprehensive care
The challenges faced in the design, conduct and analysis of surgical randomised controlled trials
Randomised evaluations of surgical interventions are rare; some interventions have been widely
adopted without rigorous evaluation. Unlike other medical areas, the randomised controlled trial
(RCT) design has not become the default study design for the evaluation of surgical interventions.
Surgical trials are difficult to successfully undertake and pose particular practical and methodological challenges. However, RCTs have played a role in the assessment of surgical innovations and there is scope and need for greater use. This article will consider the design, conduct and analysis of an RCT of a surgical intervention. The issues will be reviewed under three
headings: the timing of the evaluation, defining the research question and trial design issues.
Recommendations on the conduct of future surgical RCTs are made. Collaboration between
research and surgical communities is needed to address the distinct issues raised by the assessmentof surgical interventions and enable the conduct of appropriate and well-designed trials.The Health Services Research Unit is funded by the Scottish Government Health DirectoratesPeer reviewedPublisher PD
Falls Assessment Clinical Trial (FACT): design, interventions, recruitment strategies and participant characteristics
<p>Abstract</p> <p>Background</p> <p>Guidelines recommend multifactorial intervention programmes to prevent falls in older adults but there are few randomised controlled trials in a real life health care setting. We describe the rationale, intervention, study design, recruitment strategies and baseline characteristics of participants in a randomised controlled trial of a multifactorial falls prevention programme in primary health care.</p> <p>Methods</p> <p>Participants are patients from 19 primary care practices in Hutt Valley, New Zealand aged 75 years and over who have fallen in the past year and live independently. Two recruitment strategies were used – waiting room screening and practice mail-out. Intervention participants receive a community based nurse assessment of falls and fracture risk factors, home hazards, referral to appropriate community interventions, and strength and balance exercise programme. Control participants receive usual care and social visits. Outcome measures include number of falls and injuries over 12 months, balance, strength, falls efficacy, activities of daily living, quality of life, and physical activity levels.</p> <p>Results</p> <p>312 participants were recruited (69% women). Of those who had fallen, 58% of people screened in the practice waiting rooms and 40% when screened by practice letter were willing to participate. Characteristics of participants recruited using the two methods are similar (p > 0.05). Mean age of all participants was 81 years (SD 5). On average participants have 7 medical conditions, take 5.5 medications (29% on psychotropics) with a median of 2 falls (interquartile range 1, 3) in the previous year.</p> <p>Conclusion</p> <p>The two recruitment strategies and the community based intervention delivery were feasible and successful, identifying a high risk group with multiple falls. Recruitment in the waiting room gave higher response rates but was less efficient than practice mail-out. Testing the effectiveness of an evidence based intervention in a 'real life' setting is important.</p> <p>Trial registration</p> <p>Australian Clinical Trials Register ID 12605000054617.</p
The role of the helper lipid on the DNA transfection efficiency of lipopolyplex formulations.
Multifunctional, lipopolyplex formulations comprising a mixture of cationic liposomes and cationic, receptor-targeting peptides have potential use in gene therapy applications. Lipopolyplex formulations described here are typically far more efficient transfection agents than binary lipoplex or polyplex formulations. It has been shown previously that the peptide component mediates both DNA packaging and targeting of the nanoparticle while in this report we investigate the contribution of the lipid component. We hypothesised that the lipid components synergise with the peptides in the transfection process by promoting endosomal escape after lipid bilayer fusion. Lipopolyplexes were prepared with cationic liposomes comprising DOTAP with either neutral lipid DOPE or DOPC. DOPE promotes fusogenic, inverted hexagonal lipid structures while DOPC promotes more stable laminar structures. Lipopolyplexes containing DOPE showed substantially higher transfection efficiency than those formulated with DOPC, both in vitro and in vivo. DOPE-containing lipopolyplexes showed rapid endosomal trafficking and nuclear accumulation of DNA while DOPC-containing formulations remained within the late endo-lysosomal compartments. These findings are consistent with previous finding for the role of DOPE in lipoplexes and support the hypothesis regarding the function of the lipid components in lipopolyplexes. These findings will help to inform future lipopolyplex design, strategies and clinical development processes
Quantitative assessment of the expanding complementarity between public and commercial databases of bioactive compounds
<p>Abstract</p> <p>Background</p> <p>Since 2004 public cheminformatic databases and their collective functionality for exploring relationships between compounds, protein sequences, literature and assay data have advanced dramatically. In parallel, commercial sources that extract and curate such relationships from journals and patents have also been expanding. This work updates a previous comparative study of databases chosen because of their bioactive content, availability of downloads and facility to select informative subsets.</p> <p>Results</p> <p>Where they could be calculated, extracted compounds-per-journal article were in the range of 12 to 19 but compound-per-protein counts increased with document numbers. Chemical structure filtration to facilitate standardised comparisons typically reduced source counts by between 5% and 30%. The pair-wise overlaps between 23 databases and subsets were determined, as well as changes between 2006 and 2008. While all compound sets have increased, PubChem has doubled to 14.2 million. The 2008 comparison matrix shows not only overlap but also unique content across all sources. Many of the detailed differences could be attributed to individual strategies for data selection and extraction. While there was a big increase in patent-derived structures entering PubChem since 2006, GVKBIO contains over 0.8 million unique structures from this source. Venn diagrams showed extensive overlap between compounds extracted by independent expert curation from journals by GVKBIO, WOMBAT (both commercial) and BindingDB (public) but each included unique content. In contrast, the approved drug collections from GVKBIO, MDDR (commercial) and DrugBank (public) showed surprisingly low overlap. Aggregating all commercial sources established that while 1 million compounds overlapped with PubChem 1.2 million did not.</p> <p>Conclusion</p> <p>On the basis of chemical structure content <it>per se </it>public sources have covered an increasing proportion of commercial databases over the last two years. However, commercial products included in this study provide links between compounds and information from patents and journals at a larger scale than current public efforts. They also continue to capture a significant proportion of unique content. Our results thus demonstrate not only an encouraging overall expansion of data-supported bioactive chemical space but also that both commercial and public sources are complementary for its exploration.</p
Keystone symposium: The role of microenvironment in tumor induction and progression, Banff, Canada, 5–10 February 2005
The first Keystone symposium on the role of microenvironment in tumor induction and progression attracted 274 delegates from 13 countries to Banff in the heart of the Canadian Rockies. The meeting was organized by Mina Bissell, Ronald DePinho and Luis Parada, and was held concurrently with the Keystone symposium on cancer and development, chaired by Matthew Scott and Roeland Nusse. The 30 oral presentations and over 130 posters provided an excellent forum for discussing emerging data in this rapidly advancing field
- …