Transport assays were initiated by the addition to the assay tubes of 100 µl of radioactively traced proline (0.5 µCi) to a final concentration of 0.31 mM or 1.36 mM, supplemented or not with 0.5 mM T4C. V0 was measured at 28°C for 30 s, and proline transport was stopped by addition of 800 ml of cold 50 mM proline in PBS, and rapid washing by centrifugation at 10,000 g for 60 s.
The development of an inhibition control was a very valuable addition to the assay, providing an accurate indication of the impact of contaminants in extracted DNA on analytical sensitivities.
In additional experiments, heat-inactivated (56 °C for 60 min) human plasma was diluted 1 : 2 before addition to the assay.
The O2 -dominant kinetic features can be quenched by additiO2 -dominantsay of the O2–-scavenger SOD containing both Cdc25 and O2–.
Egg yolk or lyophilized egg powder was first diluted 1 10 in acidified PBS (pH = 5) and centrifuged before further dilutions in PBS and addition to the assay plate.
In addition to the assay established in this study that works at the bulk level, analytical assays at the single-molecule level can also be designed for probing the acidification of the oxygen scavenging system in situ.
Dose response experiments were performed in the same way, except that concentrated compound stocks were used (10 μM in DMSO) that were serially diluted in 100% DMSO in half log series before addition to the assay plate.
An expanded set of 59 assays was examined (Table S1), including additional pure protein- or cell-extract-based assays and cellular toxicity assays, in addition to the 24 assays used to develop the decision tree.
In addition to the HI assays conducted at the NICD as described above, the chicken sera were screened by HI assays and ELISA using antibodies specific to a low pathogenicity H5N2 virus isolated from ostriches in South Africa.
In addition to the mutagenicity assay, the comet assay is a sensitive and valuable technique to observe genotoxic damage.
