2,828 research outputs found
Correlations between plasma variables and the deposition process of Si films from chlorosilanes in low pressure RF plasma of argon and hydrogen
The dissociation of chlorosilanes to silicon and its deposition on a solid substrate in a RF plasma of mixtures of argon and hydrogen were investigated as a function of the macrovariables of the plasma. The dissociation mechanism of chlorosilanes and HCl as well as the formation of Si in the plasma state were studied by sampling the plasma with a quadrupole mass spectrometer. Macrovariables such as pressure, net RF power input and locations in the plasma reactor strongly influence the kinetics of dissociation. The deposition process of microcrystalline silicon films and its chlorine contamination were correlated to the dissociation mechanism of chlorosilanes and HCl
Operationalization and reliability testing of ICF categories relevant for physiotherapists' interventions in the acute hospital
Objective: To operationalize items based on categories of
the International Classification of Functioning, Disability
and Health (ICF) relevant to patient problems that are addressed by physiotherapeutic interventions in the acute hospital, and to test the reliability of these items when applied by physiotherapists.
Methods: A selection of 124 ICF categories was operationalized in a formal decision-making and consensus process. The reliability of the newly operationalized item list was tested with a cross-sectional study with repeated measurements.
Results: The item writing process resulted in 94 dichotomous
and 30 polytomous items. Data were collected in a convenience sample of 28 patients with neurological, musculoskeletal, cardiopulmonary, or internal organ conditions, requiring physical therapy in an acute hospital. Fifty-six percent of the polytomous and 68% of the dichotomous items had a raw agreement of 0.7 or above, whereas 36% of all polytomous and 34% of all dichotomous items had a kappa coefficient of 0.7 and above.
Conclusion: The study supports that the ICF is adaptable to
professional and setting-specific needs of physiotherapists.
Further research towards the development of reliable instruments for physiotherapists based on the ICF seems justified.
Key words: ICF; classification; reliability; outcome measures; health status assessment
Comparative study of the persistence of anti-HIV activity of deoxynucleoside HIV reverse transcriptase inhibitors after removal from culture
<p>Abstract</p> <p>Background</p> <p>Most in vitro assays of drug potency may not adequately predict the performance in vivo. Methods to assess the persistence of antiviral activity of deoxynucleoside analogs, which require intracellular activation to the active metabolites that can persist in cells, will be important for designing dosages, combination regimens, and assessing treatment compliance. Using an HIV-IIIB/TZM-bl indicator cell culture system, we assessed the ability of an inhibitor to protect cells from infection and to delay viral rebound after removal of inhibitor from culture.</p> <p>Results</p> <p>The order of protection of cells from HIV-infection was 4'-Ed4T > LFD4C > DDI > D4T > 3TC > AZT > FTC > NVP. The fold-increase in EC<sub>50 </sub>to delay viral rebound was DDI < 4'-Ed4T < LFD4C < FTC < D4T < 3TC < NVP < AZT. The ranking of persistence of anti-HIV activity of the inhibitors based on the two-component assay was DDI > 4'-Ed4T > LFD4C > FTC = D4T > 3TC > NVP > AZT.</p> <p>Conclusion</p> <p>The persistence ranking was derived from assays based on measures of single viral replication-cycle and cumulative inhibition at multiple time-points. Therefore, a better indicator of the pharmacodynamic property of an inhibitor. The persistence of anti-HIV activity assay may complement in vitro potency assays to better predict in vivo performance of nucleoside analogs.</p
Activation of PKC-ε counteracts maturation and apoptosis of HL-60 myeloid leukemic cells in response to TNF family members
Protein kinase C (PKC)-ε, a component of the serine/threo-nine PKC family, has been shown to influence the survival and differentiation pathways of normal hematopoietic cells. Here, we have modulated the activity of PKC-ε with specific small molecule activator or inhibitor peptides. PKC-ε inhibitor and activator peptides showed modest effects on HL-60 maturation when added alone, but PKC-ε activator peptide significantly counteracted the pro-maturative activity of tumor necrosis factor (TNF)-α towards the monocytic/macrophagic lineage, as evaluated in terms of CD14 surface expression and morphological analyses. Moreover, while PKC-ε inhibitor peptide showed a reproducible increase of TNF-related apoptosis inducing ligand (TRAIL)-induced apoptosis, PKC-ε activator peptide potently counteracted the pro-apoptotic activity of TRAIL. Taken together, the anti-maturative and anti-apoptotic activities of PKC-ε envision a potentially important proleukemic role of this PKC family member
Minimum data set to measure rehabilitation needs and health outcome after major trauma : application of an international framework
BACKGROUND: Measurement of long term health outcome after trauma remains non-standardized and ambiguous which limits national and international comparison of burden of injuries. The World Health Organization (WHO) has recommended the application of the International Classification of Function, Disability and Health (ICF) to measure rehabilitation and health outcome worldwide. No previous poly-trauma studies have applied the ICF comprehensively to evaluate outcome after injury.
AIM: To apply the ICF categorization in patients with traumatic injuries to identify a minimum data set of important rehabilitation and health outcomes to enable national and international comparison of outcome data.
DESIGN: A mixed methods design of patient interviews and an on-line survey.
SETTING: An ethnically diverse urban major trauma center in London.
POPULATION: Adult patients with major traumatic injuries (poly-trauma) and international health care professionals (HCPs) working in acute and post-acute major trauma settings.
METHODS: Mixed methods investigated patients and health care professionals (HCPs) perspectives of important rehabilitation and health outcomes. Qualitative patient data and quantitative HCP data were linked to ICF categories. Combined data were refined to identify a minimum data set of important rehabilitation and health outcome categories.
RESULTS: Transcribed patient interview data (N.=32) were linked to 234 (64%) second level ICF categories. Two hundred and fourteen HCPs identified 121 from a possible 140 second level ICF categories (86%) as relevant and important. Patients and HCPs strongly agreed on ICF body structures and body functions categories which include temperament, energy and drive, memory, emotions, pain and repair function of the skin. Conversely, patients prioritised domestic tasks, recreation and work compared to HCP priorities of self-care and mobility. Twenty six environmental factors were identified. Patient and HCP data were refined to recommend a 109 possible ICF categories for a minimum data set.
CONCLUSIONS: The comprehensive measurement of health outcomes after trauma is important for patients, health professionals and trauma systems. An internationally applied ICF minimum data set will standardize the language used and concepts measured after major trauma to enable national and international comparison of outcome data
Neonatal hearing screening: modelling cost and effectiveness of hospital- and community-based screening
This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: Children with congenital hearing impairment benefit from early detection and management of their hearing loss. These and related considerations led to the recommendation of universal newborn hearing screening. In 2001 the first phase of a national Newborn Hearing Screening Programme (NHSP) was implemented in England. Objective of this study was to assess costs and effectiveness for hospital and community-based newborn hearing screening systems in England based on data from this first phase with regard to the effects of alterations to parameter values. METHODS: DESIGN: Clinical effectiveness analysis using a Markov Model. OUTCOME MEASURE: quality weighted detected child months (QCM). RESULTS: Both hospital and community programmes yielded 794 QCM at the age of 6 months with total costs of 3,690,000 pound sterling per 100,000 screened children in hospital and 3,340,000 pound sterling in community. Simulated costs would be lower in hospital in 48% of the trials. Any statistically significant difference between hospital and community in prevalence, test sensitivity, test specificity and costs would result in significant differences in cost-effectiveness between hospital and community. CONCLUSION: This modelling exercise informs decision makers by a quantitative projection of available data and the explicit and transparent statements about assumptions and the degree of uncertainty. Further evaluation of the cost-effectiveness should focus on the potential differences in test parameters and prevalence in these two settings.This work was undertaken by the Evaluation Team for the Implementation
Pilot of Newborn Hearing Screening in England which received funding
from the Department of Health
Moonlighting function of Phytochelatin synthase1 in extracellular defense against fungal pathogens
Phytochelatin synthase (PCS) is a key component of heavy metal detoxification in plants. PCS catalyzes both the synthesis of the peptide phytochelatin from glutathione and the degradation of glutathione conjugates via peptidase activity. Here, we describe a role for PCS in disease resistance against plant pathogenic fungi. The pen4 mutant, which is allelic to cadmium insensitive1 (cad1/pcs1) mutants, was recovered from a screen for Arabidopsis mutants with reduced resistance to the nonadapted barley fungal pathogen Blumeria graminis f. sp. hordei. PCS1, which is found in the cytoplasm of cells of healthy plants, translocates upon pathogen attack and colocalizes with the PEN2 myrosinase on the surface of immobilized mitochondria. pcs1 and pen2 mutant plants exhibit similar metabolic defects in the accumulation of pathogen-inducible indole glucosinolate-derived compounds, suggesting that PEN2 and PCS1 act in the same metabolic pathway. The function of PCS1 in this pathway is independent of phytochelatin synthesis and deglycination of glutathione conjugates, as catalytic-site mutants of PCS1 are still functional in indole glucosinolate metabolism. In uncovering a peptidase-independent function for PCS1, we reveal this enzyme to be a moonlighting protein important for plant responses to both biotic and abiotic stresses
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