A two-state model for the kinetics of competitive radioligand binding.

Background And Purpose: Ligand-receptor binding kinetics is receiving increasing attention in the drug research community. The Motulsky and Mahan model, a one-state model, offers a method for measuring the binding kinetics of an unlabelled ligand, with the assumption that the labelled ligand has no preference while binding to distinct states or conformations of a drug target. As such, the one-state model is not applicable if the radioligand displays biphasic binding kinetics to the receptor.

Structure-Activity Relationships of the Sustained Effects of Adenosine A2A Receptor Agonists Driven by Slow Dissociation Kinetics.

The duration of action of adenosine A receptor (A2A) agonists is critical for their clinical efficacy, and we sought to better understand how this can be optimized. The in vitro temporal response profiles of a panel of A2A agonists were studied using cAMP assays in recombinantly (CHO) and endogenously (SH-SY5Y) expressing cells. Some agonists (e.

Progress in phosphors and filters for luminescent solar concentrators.

Luminescent solar concentrators would allow for high concentration if losses by reabsorption and escape could be minimized. We introduce a phosphor with close-to-optimal luminescent properties and hardly any reabsorption. A problem for use in a luminescent concentrator is the large scattering of this material; we discuss possible solutions for this.

Ferroelectric thin-film capacitors and piezoelectric switches for mobile communication applications.

Thin-film ferroelectric capacitors have been integrated with resistors and active functions such as ESD protection into small, miniaturized modules, which enable a board space saving of up to 80%. With the optimum materials and processes, integrated capacitors with capacitance densities of up to 100 nF/mm2 for stacked capacitors combined with breakdown voltages of 90 V have been achieved. The integration of these high-density capacitors with extremely high breakdown voltage is a major accomplishment in the world of passive components and has not yet been reported for any other passive integration technology.

Improved performance of seroconversion with a 4th generation HIV antigen/antibody assay.

Recently a new fourth generation microELISA for large scale blood screening has been described in which HIV p24 Ag detection was integrated in an anti-HIV-1/-2 and anti-HIV-1 group O assay based on a direct assay format: (Vironostika HIV Uni-Form II Ag/Ab (Van Binsbergen et al., (1998)). When compared to the third generation a-HIV assay (Vironostika HIV Uni-Form II plus O), the seroconversion window was narrowed with more than one week.

Strongly enhanced sensitivity of a direct anti-HIV-1/-2 assay in seroconversion by incorporation of HIV p24 ag detection: a new generation vironostika HIV Uni-Form II.

The clinical sensitivity of the current anti-HIV assays is based for an important part on their reactivity with seroconversion panels. The most sensitive assay closes the seroconversion window as much as possible, thereby reducing the risk of transmitting false negative donations obtained from individuals infected recently. Because of the absence of anti-HIV antibodies during the early phase of infection, the seroconversion window can be narrowed partially by detection of HIV p24 Ag.

Reactivity of a new HIV-1 group O third generation A-HIV-1/-2 assay with an unusual HIV-1 seroconversion panel and HIV-1 group O/group M subtyped samples.

It was shown previously that about 97% of the anti-HIV-1 group O strain-positive samples were detected by crossreaction with native HIV-1 gp160 (Van Binsbergen et al., Evaluation of a new third generation anti-HIV-1/anti-HIV-2 assay with increased sensitivity for HIV-1 group O, J. Virol.

New developments in ELISA verification of anti-HIV screening of blood donors.

First generation ELISA screening assays for antibodies to HTLV-III (HIV) generated between 0.1 and 1.0% false positive results.