assays in drug discovery and life science research. These assays are used, for example, in assay development to determine appropriate concentration ranges, in secondary screening to evaluate pharmacological response, and in early Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) to determine toxicological effects. The ability to rapidly and accurately produce dilution curves ...

We have modified the EMIT (Syva) serum digoxin assay for use with a mini-disc centrifugal analyzer. A minicomputer is used to control data acquisition, calculations, and readout for 14 cuvettes simultaneously. Thus, it is not necessary for time each individual assay manually or to plot calibration curves on graph paper. We use incubation times and dilutions similar to those used for the manual ...

An enzyme-linked immunosorbent assay was developed for measuring immunoglobulin G anti-diphtheric toxin antibodies in human serum. The assay was done in plastic plates coated with purified diphtheric toxoid. Since a straight-line relationship was found between logs of extinction values and of antibody concentrations, with a very constant slope, serum titers could be expressed as log10 of the se...

When steady state chemostat cultures are abruptly exposed to substrateexcess conditions, they exhibit long lags before adjusting to the new environment. The identity of the rate-limiting step for this slow response can be inferred from the initial yields and specific growth rates measured by exposing steady state cultures at various dilution rates to substrate-excess conditions. We measured the...

Korea is known as a hepatitis B virus-endemic area with a high incidence of hepatocellular carcinoma (HCC) [1]. Alpha-fetoprotein (AFP) is the most widely used tumor marker for monitoring HCC in clinical practices. The serum AFP level is <10 ng/mL in healthy adults, but patients with HCC show a very wide distribution of AFP levels. AFP level is known to increase in 60-70% of patients with HCC [...

Historically, quantitation of virus-specific CD8+ T cells has been accomplished by limiting dilution analysis of cytotoxic precursor cells. Recent studies have shown that this technique greatly underestimates the actual number of antigen-specific cells and have provided new insight into anti-viral immune responses.

BACKGROUND Measurement of late-night salivary cortisol concentrations is increasingly used as a screening test in suspected Cushing's syndrome. Cortisol concentrations are typically extremely low in late-night samples and discordant assay-specific reference ranges have been reported. Therefore, the aim of our study was to assess the analytical performance of the first automated cortisol immunoa...

Organic infusions created by fermenting white oak (Quercus alba L.) leaves in water were evaluated as sources of attractant odorants and contact oviposition stimulants for gravid Aedes albopictus (Skuse) and Aedes triseriatus (Say). Infusions were bioassayed in the laboratory by giving single females a choice of ovipositing in 1 container with infusion and 7 containers with water. Ae. albopictu...

Lymphocytes from rheumatoid arthritis patients have been fused with drug-marked human myeloma cell lines and hybrids selected which secrete rheumatoid factors. Limiting dilution and soft agarose plates have been used to clone these hybrids, but so far stable clones have not been obtained. Epstein-Barr virus has been used to transform lymphocytes, and clones which secrete rheumatoid factors have...

Heterogeneity within tumors is becoming increasingly recognized as an important cause of treatment failure in cancer. Two recent studies use fate-mapping and limiting dilution transplantation assays to identify SRY (sex determining region Y)-box 2 (Sox2) as cancer stem-cell marker and driver of cancer stemness.