1,068 research outputs found
ESTIMATING DETERMINANTS OF STUDENT EVALUATION SCORES TO IMPROVE TEACHING
Student evaluations are used for both formative and summative assessment of teachers. This paper provides a method to make more effective use of these student evaluations by individual teachers. Data on three years of evaluations in two courses were used to develop regression models to explain overall effectiveness of teaching. The relative importance of explanatory variables changed with the course taught.Teaching/Communication/Extension/Profession,
An evolutionarily-unique heterodimeric voltage-gated cation channel found in aphids
We describe the identification in aphids of a unique heterodimeric voltage-gated sodium channel which has an atypical ion selectivity filter and, unusually for insect channels, is highly insensitive to tetrodotoxin. We demonstrate that this channel has most likely arisen by adaptation (gene fission or duplication) of an invertebrate ancestral mono(hetero)meric channel. This is the only identifiable voltage-gated sodium channel homologue in the aphid genome(s), and the channelâs novel selectivity filter motif (DENS instead of the usual DEKA found in other eukaryotes) may result in a loss of sodium selectivity, as indicated experimentally in mutagenised Drosophila channels
Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed COVIDâ19 infection to improve patient outcomes and to protect healthcare workers treating them (Review)
A C K N O W L E D G E M E N T S: We would like to thank the peer reviewers, Professor Jeremy Bagg, Dr Karolin Hijazi, Professor Carl Philpott and Professor Claire Hopkins, fortheirinsightful comments, which helped us to improve these reviews. Thanks also to Professor Peter Tugwell, Senior Editor Cochrane MOSS Network, for acting as sign-oF editor for these projects. We are also grateful to Doug Salzwedel from the Cochrane Hypertension Group for providing search peer review comments for the draK search strategy. Professor Schilder's time for this project was supported by the National Institute for Health Research, University College London Hospitals Biomedical Research Centre, London, UK. This project was supported by the National Institute for Health Research, via Cochrane Infrastructure, Cochrane Programme Grant or Cochrane Incentive funding to Cochrane ENT and Cochrane Oral Health. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the Systematic Reviews Programme, NIHR, NHS or the Department of Health.Peer reviewedPublisher PD
Heavy mineral analysis by ICP-AES a tool to aid sediment provenancing
Correlation and provenancing of sediments/sedimentary rocks can be achieved by several techniques; a common approach is through the identification and quantification of heavy minerals using a petrological microscope. This can be time consuming, the analysis of heavy minerals by inductively coupled plasma atomic emission spectroscopy offers a faster alternative, by determining key elements associated with specific heavy minerals. Here we outline a method for determining heavy mineral species though ICP-AES using high temperature fusion with a lithium metaborate flux to ensure complete dissolution of resistate minerals. The method was tested in a provenance study of desert sands from the United Arab Emirates. The results are compared with those derived from traditional optical microscopy. These show good agreement for minerals with specific geochemical signatures, whilst the overall geochemistry of the heavy mineral concentrate was diagnostic of potential sediment sources. This geochemical approach is capable of processing large numbers of samples rapidly and is advocated as a screening technique. A combination of geochemical and mineralogical data produced by these techniques provides a powerful diagnostic tool for studies of heavy mineral signatures in sediments frequently used in mineral reconnaissance, paleogeographic reconstruction and reservoir characterisation in the petroleum industry
Haplotyping the human leukocyte antigen system from single chromosomes
We describe a method for determining the parental HLA haplotypes of a single individual without recourse to conventional segregation genetics. Blood samples were cultured to identify and sort chromosome 6 by bivariate flow cytometry. Single chromosome 6 amplification products were confirmed with a single nucleotide polymorphism (SNP) array and verified by deep sequencing to enable assignment of both alleles at the HLA loci, defining the two haplotypes. This study exemplifies a rapid and efficient method of haplotyping that can be applied to any chromosome pair, or indeed all chromosome pairs, using a single sorting operation. The method represents a cost-effective approach to complete phasing of SNPs, which will facilitate a deeper understanding of the links between SNPs, gene regulation and protein function
[Accepted Manuscript] Reduced-cost Chlamydia trachomatis-specific multiplex real-time PCR diagnostic assay evaluated for ocular swabs and use by trachoma research programmes.
Trachoma, caused by the intracellular bacterium Chlamydia trachomatis (Ct) is the leading infectious cause of preventable blindness. Many commercial platforms are available that provide highly sensitive and specific detection of Ct DNA. However, the majority of these commercial platforms are inaccessible for population-level surveys in resource-limited settings typical to trachoma control programmes. We developed two low-cost quantitative PCR (qPCR) tests for Ct using readily available reagents on standard real-time thermocyclers.
Each multiplex quantitative PCR test targets one genomic and one plasmid Ct target in addition to an endogenous positive control for Homo sapiens DNA. The quantitative performance of the qPCR assays in clinical samples was determined by comparison to a previously evaluated droplet digital PCR (ddPCR) test. The diagnostic performance of the qPCR assays were evaluated against a commercial assay (artus C. trachomatis Plus RG PCR, Qiagen Ltd) using molecular diagnostics quality control standards and clinical samples. We examined the yield of Ct DNA prepared from five different DNA extraction kits and a cold-chain free dry-sample preservation method using swabs 'spiked' with fixed concentrations of human and Ct DNA.
The qPCR assay was highly reproducible (Ct plasmid and genomic targets mean total coefficients of variance 41.5% and 48.3%, respectively). The assay detected 8/8 core specimens upon testing of a quality control panel and performed well in comparison to commercially marketed comparator test (sensitivity and specificity>90%). Optimal extraction and sample preservation methods for research applications were identified.
We describe a pipeline from collection to diagnosis providing the most efficient sample preservation and extraction with significant per test cost savings over a commercial qPCR diagnostic assay. The assay and its evaluation should allow control programs wishing to conduct independent research within the context of trachoma control, access to an affordable test with defined performance characteristics
Trachoma
Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectiousâinflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individualâs lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse
Protocol for a multi-centre observational and mixed methods pilot study to identify factors predictive of poor functional recovery after major gastrointestinal surgery and strategies to enhance uptake of perioperative optimization. Optimizing the care and treatment pathways for older patients facing major gastrointestinal surgery (OCTAGON)
Introduction: National datasets report large variations in outcomes from older people (â„65Â years) between different UK surgical units. This implies that not all patients receive the same level of care or access to resources, such as rehabilitation or allied health professional input. This might impact functional decline. Aims: Our aim is to evaluate the baseline status of older patients facing major gastrointestinal surgery and the impact of variation in perioperative assessment and provision of perioperative support on functional outcomes. Patientsâ experiences and views of assessment and optimization will be explored via integrated qualitative semi-structured interviews. Methods and analysis: This multi-centre, pilot cohort study will include patients â„65Â years presenting via both elective and emergency pathways at three to five South Yorkshire NHS hospitals (Clinical Trials registration NCT04545125). The primary outcome is functional recovery measured using the World Health Organization Disability Assessment Schedule 2.0 at 6Â weeks post-operation. Secondary outcomes include feasibility, quality of life, length of stay and complication rate. An opportunistic sample size of 120Â has been estimated and will inform the design of a future, adequately powered study. For the qualitative study, 20â30 semi-structured patient interviews will be undertaken with patients from the cohort study to explore experiences of assessment and optimization. Interviews will be digitally recorded, transcribed verbatim and analysed according to the framework approach. Ethics and dissemination: This study has been approved by the National Health Service Research Ethics Committee and is registered centrally with Health Research Authority. It has been adopted by the National Institute for Health Research Portfolio scheme. Dissemination will be via international and national surgical and geriatric conferences
Indentifying published studies of care home research: an international survey of researchers
Collating the published research around institutional, long term care is confounded by the differing terminologies used to describe this health-care setting. We aimed to collate the descriptors used by researchers to inform the future development of a âsearch filterâ (a collection of search terms to help identify relevant records from electronic literature databases). We surveyed international researchers via the Nursing Home Research International Working Group, European Geriatric Medicine Society and published reviewers, achieving at 38% response rate across 21 countries. Our findings identified variation in terminology used by researchers to describe long-term care settings in their country of practice. Nursing home was the most accepted term (96%). âHomes for the Agedâ was selected by 48% of respondents. A range of terms are likely to be necessary to identify all relevant research and these may not be intuitive. We will use these data to help inform development of a search filter
The role of cytokine gene polymorphisms in the pathogenesis of abdominal aortic aneurysms: A case-control study
AbstractBackground: Cytokines are the primary mediators of inflammation and also influence matrix metalloproteinase expression, both of which are important in development of abdominal aortic aneurysm (AAA). A significant, but as yet unknown, familial factor contributes to the pathogenesis of AAA. Many cytokine genes contain polymorphic sites, some of which affect cytokine production in vitro. Cytokine gene polymorphisms may therefore influence the pathogenesis of AAA. The purpose of this study was to determine whether there is any association between cytokine gene polymorphisms and AAA. Methods and Results: This case-control study comprised 100 patients with AAA and 100 age-matched and sex-matched control subjects. For each case and control subject in the study, genotypes at the following cytokine gene polymorphic loci were determined: interleukin (IL)-1ÎČ +3953, IL-6 â174, IL-10 â1082, IL-10 â592, and tumor necrosis factors-α â308. Allele and genotype frequencies were compared between AAA and control groups, and odds ratios (OR) were calculated for the presence of AAA with each allele at each locus examined as risk factors. The IL-10 â1082 A allele was significantly more common in the AAA group than the control group (P =.03). The OR for the IL-10 â1082 A allele as a risk factor for AAA was 1.8 (95% confidence interval, 0.9-3.6). Discussion: These associations suggest a significant role for IL-10 in the pathogenesis of AAA. This association of AAA with the IL-10 â1082 A allele is also biologically plausible; the IL-10 â1082 A allele is associated with low IL-10 secretion, and it may be that AAA develops in patients who are unable to mount the same anti-inflammatory response as those who do not have AAA. (J Vasc Surg 2003;37:999-1005.
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