68 research outputs found
Biochemical and molecular approaches to the study of iron nutrition in the marine cyanobacterium synechococcus WH 7803
Field work with natural phytoplankton assemblages using conventional oceanographic techniques, has established the limited ability of such methods to be able to identify the existence of iron-deplete conditions in the North Atlantic Ocean. Such results confirmed the requirement of "novel" detection methods to determine whether phytoplankton are iron limited in non-productive waters.
Carotenoid-containing cell walls from the marine cyanobacterium Synechococcus WH 7803 contained two major polypeptides of Mr - 94,000 and 67,000. The larger of the two appeared to be heat modifiable, a characteristic of porins. Western blot analysis showed that the cell walls from different species of cyanobacteria and one prochlorophyte exhibited a high degree of antigenic relatedness.
The effects of iron-deplete conditions upon the outer membrane protein (OMP) profile of Synechococcus WH 7803 was simulated by the addition of 15 nq ml-1 EDDA to normal growth medium. Initial SDS-PAGE analysis revealed the presence of specific iron-regulated outer-membrane proteins. The size of the polypeptides present depended upon the type of iron limitation imposed.
Light-stimulated 35S-methionine uptake and incorporation into protein was observed with Synechococcus WH 7803. The reproducibility and sensitivity of this technique resulted in its use as a detection system for the synthesis of iron- regulated membrane proteins. After 21-48 hr growth of Synechococcus WH 7803 cells in iron-deplete medium a protein of Mj. 36,000 was synthesized. Repression of the protein's synthesis occurred after 24 hr growth in iron-replete medium. This protein was localized to both the internal membrane and the cell wall. By contrast, antibodies raised against the 36,000 Da polypeptide were able to detect the protein in internal membrane, cell wall and whole cell fractions of Synechococcus WH 7803 cells grown in both iron-replete and deplete medium. This suggests that the protein is expressed constitutively.
Although partial characterization of the 36,000 Da polypeptide has, as yet, been unsuccessful, certain characteristics of the protein were reminiscent of those of TonB. Antibodies raised against a synthetic peptide containing the x-proline dipeptide repeat of TonB were unable to detect a similar protein in Synechococcus WH 7803.
However, Southern hybridization analysis using both the S. typhimurium tonb gene and an oligonucleotide probe constructed against the TonB Lys-Pro dipeptide repeat, suggest the presence of a TonB homologue. Once the blockage has been removed from the N-terminus of the 36 kDa protein the sequence should hopefully yield conclusive evidence as to the protein's function.
Sequestration of iron by Synechococcus WH 7803 cells was observed using flame atomic absorption spectroscopy on whole cell samples. Such sequestration suggests the presence of iron storage proteins. Western blot analysis and Mossbauer spectroscopy confirmed the presence of an iron storage protein namely bacterioferritin. The 57Fe associated with the storage protein was in the same form as that found in the bacterioferritins of B.coli and P.aeruginosa, as determined by Mossbauer spectroscopy. In addition, siderophore production has not been found in this cyanobacterium
Assessment of musculoskeletal examination skills of 4th year medical students using a novel OSCE
Objective: Despite the high prevalence of musculoskeletal complaints presenting to physicians in the United States, there are very few opportunities for University of Michigan clinical medical students to receive formative or summative assessment of their ability to evaluate patients with these complaints. The purpose of this study was to assess 4th year students’ ability to examine and diagnose several common musculoskeletal disorders using a novel objective structured clinical examination (OSCE).
Methods: A multidisciplinary team of musculoskeletal specialists developed the content and structure of three OSCE stations focusing on examination of the shoulder, back and knee. For each station, volunteer M4 students were provided a clinical vignette with three possible diagnoses to consider, and were instructed to anticipate physical examination maneuvers or findings that would discriminate between the three diagnoses. Then they would examine a professional patient simulating findings associated with one of the diagnoses and choose their favored diagnosis. Their encounter was directly observed by a faculty member who scored their performance on selected physical examination maneuvers based on a checklist (0 = not done, 1 = partially done, 2 = fully done). Each encounter was recorded to allow for later review by another faculty. Immediate feedback was provided to students at the end of the OSCE, making this a formative as well as summative assessment experience. Faculty received verbal and written instruction on how to score students. IRB exemption was obtained for this study.
Results: 44 M4 students participated in the OSCE during the spring of 2012. General performance of M4 students in examining regional musculoskeletal complaints will be reported. Performance of individuals will be correlated with: anticipation of discriminatory features prior to examining the patients; self-assessment on ability to perform the relevant exam and anticipated need to do so in their future career; previous musculoskeletal elective exposure; future career choice; and performance on the M4 Comprehensive Clinical Assessment “Back pain” and “Abdominal pain” stations.
Conclusions: Initial validity evidence for a multistation musculoskeletal OSCE will be presented, as will the performance of a sampling of the 2012 graduating UM medical student class. This data will be used as part of ongoing evaluation of the longitudinal musculoskeletal curriculum at the University of Michigan medical school.http://deepblue.lib.umich.edu/bitstream/2027.42/91291/1/MedEdDay2012-poster-monradetal.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/91291/3/MEDC22poster.pd
Editorial Perspective: Speaking up for developmental language disorder - the top 10 priorities for research
Developmental language disorder (DLD) is one of the most common neurodevelopmental conditions, yet is chronically underserved, with far fewer children receiving clinical services than expected from prevalence estimates, and very little research attention relative to other neurodevelopmental conditions of similar prevalence and severity. This editorial describes a research priority-setting exercise undertaken by the Royal College of Speech and Language Therapists, which aims to redress this imbalance. From consultations with researchers, practitioners and individuals with lived experience, 10 research priorities emerge. Our goal is to share these priorities with the wider research community, to raise awareness and encourage research collaboration to improve outcomes for young people with DLD
Gender Differences in Perceptions and Self-Reported Driving Behaviors Among Teenagers. (Poster)
Research priorities relating to communication and swallowing for people with learning disabilities across the lifespan
Purpose
This research priority setting partnership (PSP) aims to collaboratively identify the “top ten” research priorities relating to communication and swallowing for children and adults with learning disabilities, across the lifespan in the UK, using a modified James Lind Alliance approach.
Design/methodology/approach
A steering group and reference group were established to oversee the PSP. A survey of speech and language therapists (SLTs) resulted in 157 research suggestions. These were further developed into 95 research questions through a multi-stakeholder workshop. Questions were prioritised via an online card-sort activity completed by SLTs, health-care or education professionals and carers. Research questions were analysed thematically. Ten adults with learning disabilities were supported to assign ratings to themes reflecting their prioritisation. The top ten research priorities were identified by combining results from these activities.
Findings
The top ten research priorities related to intervention, outcome measurement and service delivery around communication and dysphagia.
Originality/value
To the best of the authors’ knowledge, this is the first UK-wide research PSP on learning disabilities and speech and language therapy across the lifespan. It uses a novel approach to incorporate the preferences of people with learning disabilities in the prioritisation
Research priorities to improve the health of children and adults with dysphagia: a National Institute of Health Research and Royal College of Speech and Language Therapists research priority setting partnership
Objective To conduct the first UK-wide research priority setting project informing researchers and funders of critical knowledge gaps requiring investigation to improve the health and well-being of patients with eating, drinking and swallowing disorders (dysphagia) and their carers.
Design A priority setting partnership between the National Institute of Health Research (NIHR) and the Royal College of Speech and Language Therapists using a modified nominal group technique. A steering group and NIHR representatives oversaw four project phases: (1) survey gathering research suggestions, (2) verification and aggregation of suggestions with systematic review research recommendations, (3) multistakeholder workshop to develop research questions, (4) interim priority setting via an online ranking survey and (5) final priority setting.
Setting UK health services and community.
Participants Patients with dysphagia, carers and professionals who work with children and adults with dysphagia from the UK.
Results One hundred and fifty-six speech and language therapists submitted 332 research suggestions related to dysphagia. These were mapped to 88 research recommendations from systematic reviews to form 24 ‘uncertainty topics’ (knowledge gaps that are answerable by research). Four patients, 1 carer and 30 healthcare professionals collaboratively produced 77 research questions in relation to these topics. Thereafter, 387 patients, carers and professionals with experience of dysphagia prioritised 10 research questions using an interim prioritisation survey. Votes and feedback for each question were collated and reviewed by the steering and dysphagia reference groups. Nine further questions were added to the long-list and top 10 lists of priority questions were agreed.
Conclusion Three top 10 lists of topics grouped as adults, neonates and children, and all ages, and a further long list of questions were identified by patients, carers and healthcare professionals as research priorities to improve the lives of those with dysphagia
Aquatic Macroinvertebrate Biodiversity Associated with Artificial Agricultural Drainage Ditches
Agricultural drainage channels and ditches are ubiquitous features in the lowland agricultural landscapes, built primarily to facilitate land drainage, irrigate agricultural crops and alleviate flood risk. Most drainage ditches are considered artificial waterbodies and are not typically included in routine monitoring programmes, and as a result the faunal and floral communities they support are poorly quantified. This paper characterizes the aquatic macroinvertebrate diversity (alpha, beta and gamma) of agricultural drainage ditches managed by an internal drainage board in Lincolnshire, UK. The drainage ditches support very diverse macroinvertebrate communities at both the site (alpha diversity) and landscape scale (gamma diversity) with the main arterial drainage ditches supporting greater numbers of taxa when compared to smaller ditches. Examination of the between site community heterogeneity (beta diversity) indicated that differences among ditches were high spatially and temporally. The results illustrate that both main arterial and side ditches make a unique contribution to aquatic biodiversity of the agricultural landscape. Given the need to maintain drainage ditches to support agriculture and flood defence measures, we advocate the application of principles from ‘reconciliation ecology’ to inform the future management and conservation of drainage ditches
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Editorial Perspective: Speaking up for developmental language disorder - the top 10 priorities for research
Developmental language disorder (DLD) is one of the most common neurodevelopmental conditions, yet is chronically underserved, with far fewer children receiving clinical services than expected from prevalence estimates, and very little research attention relative to other neurodevelopmental conditions of similar prevalence and severity. This editorial describes a research priority-setting exercise undertaken by the Royal College of Speech and Language Therapists, which aims to redress this imbalance. From consultations with researchers, practitioners and individuals with lived experience, 10 research priorities emerge. Our goal is to share these priorities with the wider research community, to raise awareness and encourage research collaboration to improve outcomes for young people with DLD
Algae as Protein Factories: Expression of a Human Antibody and the Respective Antigen in the Diatom Phaeodactylum tricornutum
Microalgae are thought to offer great potential as expression system for various industrial, therapeutic and diagnostic recombinant proteins as they combine high growth rates with all benefits of eukaryotic expression systems. Moreover, microalgae exhibit a phototrophic lifestyle like land plants, hence protein expression is fuelled by photosynthesis, which is CO2-neutral and involves only low production costs. So far, however, research on algal bioreactors for recombinant protein expression is very rare calling for further investigations in this highly promising field. In this study, we present data on the expression of a monoclonal human IgG antibody against the Hepatitis B surface protein and the respective antigen in the diatom Phaeodactylum tricornutum. Antibodies are fully-assembled and functional and accumulate to 8.7% of total soluble protein, which complies with 21 mg antibody per gram algal dry weight. The Hepatitis B surface protein is functional as well and is recognized by algae-produced and commercial antibodies
L’utilisation du masque laryngé d’intubation en cas de spondylarthrite ankylosante sévère
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