103 research outputs found
Quantification of human complement C2 protein using an automated turbidimetric immunoassay
Background:
The measurement of complement components is clinically useful where a deficiency is suspected, or where excessive activation and consumption are present in disease. C2 deficiency carries an increased risk of developing systemic lupus erythematosus, recurrent infections and atherosclerosis. In this study, we have evaluated The Binding Site’s Human Complement C2 SPAPLUS® assay.
Methods:
Linearity was tested using 13 sample dilutions covering the standard measuring range. Within- and between-assay variabilities were calculated using five samples with different C2 concentrations. The correlation between C2 concentrations in EDTA-plasma and serum was assessed, as was the correlation between C2 measurements by the automated assay and radial immunodiffusion. C2 concentrations were compared with CH50 activity, and quantified in individuals with homozygous or heterozygous C2 deficiency, acquired angioedema and patients with chronic inflammatory conditions.
Results:
The assay was linear across the measuring range (3.8–42.3 mg/L). Intra- and interassay variability were 2.3%–3.8% and 0%–3.3%, respectively. Comparison between C2 measurements in EDTA-plasma and serum provided a strong correlation (p<0.0001, R2=0.82, slope 0.92), as did the correlation between the automated and radial immunodiffusion methods (p<0.0001, R2=0.89, slope 1.07). A positive correlation between C2 concentration and CH50 activity was demonstrated (p<0.0001, R2=0.48). Significant differences were observed between the median C2 concentrations obtained in healthy controls and the patient clinical samples, with homozygous C2-deficient patients giving below detectable results.
Conclusions:
This C2 SPAPLUS® assay allows the automated, rapid and precice quantification of complement C2 protein and could therefore be considered as a replacement for older, more time-consuming methods
Pride and confidence at work: potential predictors of occupational health in a hospital setting
BACKGROUND: This study focuses on determinants of a healthy work environment in two departments in a Swedish university hospital. The study is based on previously conducted longitudinal studies at the hospital (1994–2001), concerning working conditions and health outcomes among health care personnel in conjunction with downsizing processes. Overall, there was a general negative trend in relation to mental health, as well as long-term sick leave during the study period. The two departments chosen for the current study differed from the general hospital trend in that they showed stable health development. The aim of the study was to identify and analyse experiential determinants of healthy working conditions. METHODS: Thematic open-ended interviews were carried out with seventeen managers and key informants, representing different groups of co-workers in the two departments. The interviews were transcribed verbatim and an inductive content analysis was made. RESULTS: In the two studied departments the respondents perceived that it was advantageous to belong to a small department, and to work in cooperation-oriented care. The management approaches described by both managers and co-workers could be interpreted as transformational, due to a strain of visionary, delegating, motivating, confirmative, supportive attitudes and a strongly expressed solution-oriented attitude. The daily work included integrated learning activities. The existing organisational conditions, approaches and attitudes promoted tendencies towards a work climate characterised by trust, team spirit and professionalism. In the description of the themes organisational conditions, approaches and climate, two core determinants, work-pride and confidence, for healthy working conditions were interpreted. Our core determinants augment the well-established concepts: manageability, comprehensiveness and meaningfulness. These favourable conditions seem to function as a buffer against the general negative effects of downsizing observed elsewhere in the hospital, and in the literature. CONCLUSION: Research illuminating health-promoting aspects is rather unusual. This study could be seen as explorative. The themes and core dimensions we found could be used as a basis for further intervention studies in similar health-care settings. The result could also be used in future health promotion studies in larger populations. One of the first steps in such a strategy is to formulate relevant questions, and we consider that this study contributes to this
Meta-analysis of SHANK Mutations in Autism Spectrum Disorders: A Gradient of Severity in Cognitive Impairments.
International audienceSHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD), but their prevalence and clinical relevance remain to be determined. Here, we performed a new screen and a meta-analysis of SHANK copy-number and coding-sequence variants in ASD. Copy-number variants were analyzed in 5,657 patients and 19,163 controls, coding-sequence variants were ascertained in 760 to 2,147 patients and 492 to 1,090 controls (depending on the gene), and, individuals carrying de novo or truncating SHANK mutations underwent an extensive clinical investigation. Copy-number variants and truncating mutations in SHANK genes were present in ∼1% of patients with ASD: mutations in SHANK1 were rare (0.04%) and present in males with normal IQ and autism; mutations in SHANK2 were present in 0.17% of patients with ASD and mild intellectual disability; mutations in SHANK3 were present in 0.69% of patients with ASD and up to 2.12% of the cases with moderate to profound intellectual disability. In summary, mutations of the SHANK genes were detected in the whole spectrum of autism with a gradient of severity in cognitive impairment. Given the rare frequency of SHANK1 and SHANK2 deleterious mutations, the clinical relevance of these genes remains to be ascertained. In contrast, the frequency and the penetrance of SHANK3 mutations in individuals with ASD and intellectual disability-more than 1 in 50-warrant its consideration for mutation screening in clinical practice
Pressure UlceR Programme Of reSEarch (PURPOSE): using mixed methods (systematic reviews, prospective cohort, case study, consensus and psychometrics) to identify patient and organisational risk, develop a risk assessment tool and patient-reported outcome Quality of Life and Health Utility measures
Background: The Pressure UlceR Programme Of reSEarch (PURPOSE) consisted of two themes. Theme 1 focused on improving our understanding of individuals’ and organisational risk factors and on improving the quality of risk assessments (work packages 1–3) and theme 2 focused on developing patient-reported outcome measures (work packages 4 and 5). Methods: The programme comprised 21 individual pieces of work. Pain: (1) multicentre pain prevalence study in acute hospitals, (2) multicentre pain prevalence study in community localities incorporating (3) a comparison of case-finding methods, and (4) multicentre, prospective cohort study. Severe pressure ulcers: (5) retrospective case study, (6) patient involvement workshop with the Pressure Ulcer Research Service User Network for the UK (PURSUN UK) and (7) development of root cause analysis methodology. Risk assessment: (8) systematic review, (9) consensus study, (10) conceptual framework development and theoretical causal pathway, (11) design and pretesting of draft Risk Assessment Framework and (12) field test to assess reliability, validity, data completeness and clinical usability. Quality of life: (13) conceptual framework development (systematic review, patient interviews), (14 and 15) provisional instrument development, with items generated from patient interviews [from (1) above] two systematic reviews and experts, (16) pretesting of the provisional Pressure Ulcer Quality of Life (PU-QOL) instrument using mixed methods, (17) field test 1 including (18) optimal mode of administration substudy and item reduction with testing of scale formation, acceptability, scaling assumptions, reliability and validity, and (19) field test 2 – final psychometric evaluation to test scale targeting, item response categories, item fit, response bias, acceptability, scaling assumptions, reliability and validity. Cost–utility: (20) time trade-off task valuations of health states derived from selected PU-QOL items, and (21) validation of the items selected and psychometric properties of the new Pressure Ulcer Quality of Life Utility Index (PUQOL-UI). Key findings:Pain: prevalence studies – hospital and community patients experience both pressure area-related and pressure ulcer pain; pain cohort study – indicates that pain is independently predictive of category 2 (and above) pressure ulcer development. Severe pressure ulcers: these were more likely to develop in contexts in which clinicians failed to listen to patients/carers or recognise/respond to high risk or the presence of an existing pressure ulcer and services were not effectively co-ordinated; service users found the interactive workshop format valuable; including novel components (interviews with patients and carers) in root cause analysis improves the quality of the insights captured. Risk assessment: we developed a Pressure Ulcer Risk Assessment Framework, the PURPOSE-T, incorporating the Minimum Data Set, a screening stage, a full assessment stage, use of colour to support decision-making, and decision pathways that make a clear distinction between patients with an existing pressure ulcer(s) (or scarring from previous ulcers) who require secondary prevention and treatment and those at risk who require primary prevention (http://medhealth.leeds.ac.uk/accesspurposet). Quality of life: the final PU-QOL instrument consists of 10 scales to measure pain, exudate, odour, sleep, vitality, mobility/movement, daily activities, emotional well-being, self-consciousness and appearance, and participation (http://medhealth.leeds.ac.uk/puqol-ques). Cost–utility: seven items were selected from the PU-QOL instrument for inclusion in the PUQOL-UI (http://medhealth.leeds.ac.uk/puqol-ui); secondary study analysis indicated that item selection for the PUQOL-UI was appropriate and that the index was acceptable to patients and had adequate levels of validity. Conclusions: The PURPOSE programme has provided important insights for pressure ulcer prevention and treatment and involvement of service users in research and development, with implications for patient and public involvement, clinical practice, quality/safety/health service management and research including replication of the pain risk factor study, work exploring ‘best practice’ settings, the impact of including skin status as an indicator for escalation of preventative interventions, further psychometric evaluation of PU-QOL and PUQOL-UI the measurement of ‘disease attribution.’ Funding: The National Institute for Health Research Programme Grants for Applied Research programme
Selfish drive can trump function when animal mitochondrial genomes compete.
Mitochondrial genomes compete for transmission from mother to progeny. We explored this competition by introducing a second genome into Drosophila melanogaster to follow transmission. Competitions between closely related genomes favored those functional in electron transport, resulting in a host-beneficial purifying selection. In contrast, matchups between distantly related genomes often favored those with negligible, negative or lethal consequences, indicating selfish selection. Exhibiting powerful selfish selection, a genome carrying a detrimental mutation displaced a complementing genome, leading to population death after several generations. In a different pairing, opposing selfish and purifying selection counterbalanced to give stable transmission of two genomes. Sequencing of recombinant mitochondrial genomes showed that the noncoding region, containing origins of replication, governs selfish transmission. Uniparental inheritance prevents encounters between distantly related genomes. Nonetheless, in each maternal lineage, constant competition among sibling genomes selects for super-replicators. We suggest that this relentless competition drives positive selection, promoting change in the sequences influencing transmission
Analyse de l'expression de l'ARN messager de l'interleukine-10
Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe
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