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M Bigos N Baumgarth G C Jager O C Herman T Nozaki R T Stovel D R Parks L A Herzenberg 《Cytometry》1999,36(1):36-45
BACKGROUND: This study describes a three laser flow cytometer, reagents, and software used to simultaneously evaluate nine distinct fluorescent parameters on one cell sample. We compare the quality of data obtained with (1) full software compensation and (2) the use of partial spectral compensation of selected pairs of parameters in analog hardware, in combination with final software compensation. An application characterizing low frequency murine B cell subpopulations is given. METHODS: The fluorochromes used are: fluorescein (FITC), phycoerythrin (PE), Cy5PE and Cy7PE, excited at 488 nm by an argon laser; Texas Red (TR), allophycocyanin (APC), and Cy7APC excited at 595 nm by a pumped dye laser; and cascade blue (CB) and cascade yellow (CY) excited at 407 nm by a violet-enhanced krypton laser. Custom additions to commercial electronics and an extended optical bench allow the measurement of these nine parameters plus forward and side scatter light signals. RESULTS: We find the use of partial analog compensation reduces the variation in the background staining levels introduced by the compensation process. Novel B cell populations with frequencies below 1% are characterized. CONCLUSIONS: Nine color flow cytometry is capable of providing measurements with high information content. The choice of reagent-dye combinations and the ability to compensate in multi-parameter measurement space are crucial to obtaining satisfactory results. 相似文献
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P L Colvin E Moriguchi P H Barrett J S Parks L L Rudel 《Journal of lipid research》1999,40(10):1782-1792
We hypothesized that small HDL particles, containing two apoA-I molecules but no apoA-II (LpAI), may be converted in vivo into medium and large HDL particles, containing three or four apoA-I molecules, respectively, and that more conversion will occur in animals with higher HDL concentrations. To test this possibility, kinetic studies of small LpAI were performed in African green monkeys with either high plasma HDL cholesterol concentrations (120 +/- 36 mg/dl, mean +/- SD, n = 3) or low plasma HDL cholesterol concentrations (40 +/- 13 mg/dl, n = 3). Tracer small LpAI was purified, without ultracentrifugation, by immunoaffinity and gel filtration. After injection, the specific activity of apoA-I in small, medium, and large HDL, consisting of both LpAI and LpAI:AII particles, was followed. A multicompartmental model was developed with the simultaneous analysis of urine and plasma turnover data for the kinetics of apoA-I in small, medium, and large HDL. These analyses indicated that small HDL is converted to either medium or large HDL with little or no interconversion of medium HDL and large HDL. Much of the metabolic conversion of small HDL occurs in a sequestered pool, effectively outside the circulating plasma, in a unidirectional manner before reentering the circulating plasma as medium or large HDL. The mean fractional catabolic rate of apoA-I in small, medium, and large HDL was not different comparing the high and low HDL group. In contrast, the mean production rate of apoA-I was greater in the high HDL group compared with the low HDL group. These data support the hypothesis that the plasma concentration of HDL is primarily a function of the rate of appearance of apoA-I in medium and large HDL. 相似文献
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E. Carvalho C. Sindt A. Verdier C. Galan L. O’Donoghue S. Parks M. Thibaudon 《Aerobiologia》2008,24(4):191-201
The Coriolis δ air sampler manufactured by Bertin Technologies (France) is a continuous air sampler, dedicated to outdoor monitoring of
airborne spores and pollen grains. This high-volume sampler is based on patented Coriolis technology delivering a liquid sample.
The air is drawn into a conical vial in a whirling type motion using suction; particles are pulled against the wall by centrifugal
force. Airborne particles are separated from the air and collected in a liquid medium. This innovative solution allows rapid
analysis by several techniques including PCR assay and serological assay in order to measure the antigenicity/allergenicity
of pollen grains and fungal spores. Also, traditional counting of pollen grains or taxa identification by optical microscopy
can be done. A study has been carried out by the Health Protection Agency (HPA), Porton Down, UK, to measure the physical
efficiency of the Coriolis air sampler. The physical efficiency of the sampler for collection of micro-organism-laden particles
of various sizes has been compared with that of membrane filter samplers using the techniques described by ISO 14698-1. The
Coriolis was operated simultaneously with membrane filter samplers in a controlled room where they were challenged with uniform-sized
particles of different diameters containing bacterial spores. For the larger particle sizes, it was found that the physical
efficiency of the Coriolis was 92% for 10-μm particles. The biological performance of the Coriolis in the collection of airborne
fungal spores and pollen grains was evaluated in comparison with a Hirst spore trap (one-week tape-on-drum type sampler) which
is one of the most frequently used traps in the measurement of outdoor pollen grain concentrations. The advantages and limitations
of both technologies are discussed. The Coriolis was operated simultaneously with a Hirst spore trap in the sampling station
of Réseau National de Surveillance Aérobiologique, France (RNSA); the pollen grain and fungal spore counts were analysed by
optical microscopy. The pollen grain count m−3 collected was compared for both devices. The dispersion values were obtained and statistical analysis was carried out. This
study shows that the Coriolis air sampler provided equivalent recovery of pollen grain and fungal spores compared with the
volumetric trap standard method (not significantly different, W test, α = 0.05). Nowadays, the French-led project, acronym MONALISA, with financial support from the European Commission––Life-Environment
(LIFE05 ENV/F/000068), is testing this innovative air sampler in order to measure the antigenicity/allergenicity of the main
aeroallergen particles, i.e. Betula (birch), Poaceae (grasses), Parietaria (pellitory), Olea spp (olive tree), and Artemisia (mugwort) pollen grains, and Alternaria (fungal spores) to validate a new approach of monitoring instead of quantifying pollen grains by their morphology. The robustness
and efficiency of the MONALISA system is being demonstrated at a national level throughout Europe in eight different countries
with different bio-climatic and topography characteristics: France, UK, Finland, Poland, Spain, Portugal, Switzerland, and
Italy. 相似文献
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Joseph P. Marino Lara S. Kallander Chun Ma Hye-Ja Oh Dennis Lee Dimitri E. Gaitanopoulos John A. Krawiec Derek J. Parks Christine L. Webb Kelly Ziegler Michael Jaye Scott K. Thompson 《Bioorganic & medicinal chemistry letters》2009,19(19):5617-5621
The liver X receptors (LXR) play a key role in cholesterol homeostasis and lipid metabolism. SAR studies around tertiary-amine lead molecule 2, an LXR full agonist, revealed that steric and conformational changes to the acetic acid and propanolamine groups produce dramatic effects on agonist efficacy and potency. The new analogs possess good functional activity, demonstrating the ability to upregulate LXR target genes, as well as promote cholesterol efflux in macrophages. 相似文献
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