Short term effects of air pollution on health: a European approach using epidemiologic time series data: the APHEA protocol.
BACKGROUND AND OBJECTIVES: Results from several studies over the past five years have shown that the current levels of pollutants in Europe and North America have adverse short term effects on health. The APHEA project aims to quantifying these in Europe, using standardised methodology. The project protocol and analytical methodology are presented here. DESIGN: Daily time series data were gathered for several air pollutants (sulphur dioxide; particulate matter, measured as total particles or as the particle fraction with an aerodynamic diameter smaller than a certain cut off, or as black smoke; nitrogen dioxide; and ozone) and health outcomes (the total and cause specific number of deaths and emergency hospital admissions). The data included fulfilled the quality criteria set by the APHEA protocol. SETTING: Fifteen European cities from 10 different countries with a total population over 25 million. METHODOLOGY: The APHEA collaborative group decided on a specific methodological procedure to control for confounding effects and evaluate the hypothesis. At the same time there was sufficient flexibility to allow local characteristics to be taken into account. The procedure included modelling of all potential confounding factors (that is, seasonal and long term patterns, meteorological factors, day of the week, holidays, and other unusual events), choosing the "best" air pollution models, and applying diagnostic tools to check the adequacy of the models. The final analysis used autoregressive Poisson models allowing for overdispersion. Effects were reported as relative risks contrasting defined increases in the corresponding pollutant levels. Each participating group applied the analyses to their own data. CONCLUSIONS: This methodology enabled results from many different European settings to be considered collectively. It represented the best available compromise between feasibility, comparability, and local adaptibility when using aggregated time series data not originally collected for the purpose of epidemiological studies.
TCR signal initiation machinery is pre‐assembled and activated in a subset of membrane rafts
Recent studies suggest that rafts are involved in numerous cell functions, including membrane traffic and signaling. Here we demonstrate, using a polyoxyethylene ether Brij 98, that detergent‐insoluble microdomains possessing the expected biochemical characteristics of rafts are present in the cell membrane at 37°C. After extraction, these microdomains are visualized as membrane vesicles with a mean diameter of ∼70 nm. These findings provide further evidence for the existence of rafts under physiological conditions and are the basis of a new isolation method allowing more accurate analyses of raft structure. We found that main components of T cell receptor (TCR) signal initiation machinery, i.e. TCR–CD3 complex, Lck and ZAP‐70 kinases, and CD4 co‐receptor are constitutively partitioned into a subset of rafts. Functional studies in both intact cells and isolated rafts showed that upon ligation, TCR initiates the signaling in this specialized raft subset. Our data thus strongly indicate an important role of rafts in organizing TCR early signaling pathways within small membrane microdomains, both prior to and following receptor engagement, for efficient TCR signal initiation upon stimulation.
time series recurrent neural network metric space health care discrete wavelet transform sample size confidence interval discrete fourier transform systematic review dimensionality reduction internet service euclidean distance traffic engineering internet service provider web search engine amino acid internet traffic intensive care unit time warping similarity search background and objective x-ray computed tomography heart failure traffic classification large time body mass index early diagnosi evaluation procedure dimensionality reduction technique growth factor internet routing kidney disease signal transduction symmetric encryption chronic kidney disease sequence database chronic kidney time series database today internet scaling behavior internet backbone searchable symmetric encryption cardiac surgery series database internet traffic classification searchable symmetric oxidative stres publication bia cell surface efficient similarity external validation large time series efficient similarity search time warping distance glomerular filtration rate effective sample size hospital admission fast similarity fast similarity search plasma membrane acute kidney injury acute kidney kidney injury internet traffic engineering approximate similarity search search in large dynamic searchable area under curve kidney transplantation today internet traffic sse scheme dynamic searchable symmetric radical polymerization abbott laboratory traffic classification technique renal replacement therapy cell physiology ckd patient wide-area internet internet traffic measurement improved definition fibroblast growth factor chain transfer biological marker fibroblast growth genetic heterogeneity lipid raft excretory function cns disorder entity name part qualifier - adopted cessation of life standards characteristic complement system protein one thousand hypertensive disease limited stage (cancer stage) tissue membrane glutathione s-transferase adverse reaction to drug diameter (qualifier value) congenital abnormality kidney failure, chronic renal insufficiency creatinine measurement, serum (procedure) forecast of outcome stage level 1 microgram per liter milliliter per minute diagnosis, clinical vesicle (morphologic abnormality) lipid metabolism disorder transplanted tissue membrane protein traffic stage level 3 cfh gene hemolytic-uremic syndrome kidney failure, acute blighia sapida creatinine clearance measurement cystatin c (substance) stage level 5