BackgroundIntroduction of microbeads into flow‐cytometry has created a new scenario, making quantitative measurement of molecules dispersed in a homogeneous phase, with an extremely wide realm of already realized and potential applications possible. Development of this field has lead to specialized instrumentation and microbead arrays, dedicated to certain applications.MethodsFormaldehyde‐fixed yeast and bacterial cells were conjugated with avidin and applied as microbeads, to establish a simple, convenient, flexible, and inexpensive flow‐cytometric platform for various immunological and biochemical assays.ResultsWe have tested these “biological microbeads” for the simultaneous titration of human α‐fetoprotein (AFP) and human Chorionic Gonadotropin (βhCG) hormone levels, for the titration of proteolytic and nucleolytic (restriction) enzymes, and for quantitative PCR, using biotinylated and fluorescent primers.ConclusionsThe use of biological microbeads for various immunological and biochemical assays has been demonstrated. The flow‐cytometric methods proved to be at least as sensitive as the standard biochemical or immunological tests. For proteinase K activity measurements, a single enzyme molecule in the sample could be detected. The sensitivity, versatility, and low cost of the assays may advance flow‐cytometry to become a central methodological platform in most laboratories. The biological microbeads offer virtually unlimited possibilities for fluorescent labeling (addressing), conjugation of ligand binding molecules, and they are easy to handle and perform well in a multiplex format. © 2005 International Society for Analytical Cytology

Some recent results reported that aspirin (acetylsalicylic acid) had a positive effect on the treatment of certain types of cancer. However, the results cannot be generalized and it is not always clear whether it is a direct anticancer effect or a general health effect. Since plants produce different amounts of salicylic acid, we have sought a relationship between the salicylic acid content of some plant extracts and their anticancer activity. Growing of wheat and rice plants were carried out under controlled conditions. The salicylic acid content was determined by high-performance liquid chromatography. The viability and cell cycle assays were performed on HepG2 and Caco-2 cell lines. Despite the high content of salicylic acid, the extracts from rice plants did not show significant anticancer activity. In spite of the low salicylic acid content, the positive effect of wheat germ was confirmed in both tests. There is no direct relationship between the salicylic acid content of the plant extracts and their anticancer activity. However, it has been proven that young wheat germ is more effective than mature leaf.