Extended depth of field by colored apodization.

We describe an approach to achieving extended depth of field for a camera system based on reducing the aperture of the blue channel of a three-color camera by apodizing the lens with a yellow-colored filter. The resulting improvement in depth of field for the blue channel allows red and green channels to be digitally postprocessed for improved sharpness. Simulation confirms that our approach renders the modular transfer function of the system less dependent on object depth. Experimental test images verify the improvement in depth of field.

A double antibody radioimmunoassay for the determination of XV459, the active hydrolysis metabolite of roxifiban, in human plasma.

A radioimmunoassay (RIA) was developed for the determination of XV459, the active hydrolysis metabolite of the oral prodrug roxifiban (DMP 754), in human plasma. XV459 is a potent antagonist of the glycoprotein IIb/IIIa receptor. The method utilizes a competitive double antibody format employing an 125I-labeled XV459 analogue tracer which competes with XV459 for antibody binding sites and a second antibody precipitation step to separate antibody bound analyte from free analyte. The method has a validated lower quantification limit of 0.35 ng/ml (0.81 nM) using 12.5 microl of plasma and with dilution can accommodate clinical plasma samples ranging up to 48.0 ng/ml (110.7 nM). Cross-validation to an existing quantitative liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method showed good correlation (r(2)=0.98). The RIA has been successfully used to assay over 10000 clinical samples with sensitivity and specificity comparable to the LC-MS/MS method, but with faster turn around time and at greatly reduced costs.

Ligand and coactivator recruitment preferences of peroxisome proliferator activated receptor alpha.

The mechanism by which ligands of nuclear receptors show differential effects on gene transcription is not fully understood, but is believed to result in part from the preferential recruitment and/or displacement of coactivators and corepressors. We have explored the interaction of several known ligands and the nuclear receptor (peroxisome proliferator activated receptor alpha, PPARalpha) using scintillation proximity assay (SPA) and the interaction of LXXLL containing peptides derived from three coactivators (SRC-1, CBP and PGC-1) with PPARalpha in the presence of PPARalpha agonist ligands using fluorescence resonance energy transfer (FRET). The EC(50)s of the individual ligands for recruitment showed the same rank order regardless of the coactivator peptide used, with GW2331