Bioassays design

Note that not considered is the potential other case, where the neoplasia rates are low for both animals and humans. This is a very rare case and one for which our current bioassay designs probably lack sufficient power to be effective. 

Schmelz, E. A., Albom, H. T. and Tumlinson, J. H. (2001). The influence of intact-plant and excised-leaf bioassay designs on volicitin- and jasmonic acid-induced sesquiterpene volatile release in Zea mays. Planta 214 171-179. 

As pointed out above, the bioassay design depends on the objective(s) of the study. A bioassay to determine allelopathic interactions in the field or in an ecological setting may have a quite different design than one used to determine PGR activity of a compound or to determine its molecular mode of action. Specific bioassays can be used to follow the isolation/purification of allelochemicals, evaluate their phytotoxic (or growth simulation) effects (i.e., visual effects), determine their host range/selectivity, evaluate allelopathic action of volatile compounds, or examine physiological/biochemical effects, such as photodynamic and membrane effects, effects on photosynthesis, specific enzyme sites, and effects at the ultrastructural level to locate receptor sites or sites of injury. Several examples of useful bioassays will be presented later. 

The impact of such molecular biological manipulations has as yet been limited in terms of bioassay design. However this will not remain so for long. Based on the present demonstrations and theoretical conjecture, many novel antibody reagents may be anticipated that are relevant to the future of antibody-enzyme conjugates and their applications. 

The process from bioassay design to HTS construction can significantly change the design and final format of an assay. It is important that assay to screen reproducibility is monitored and maintained to ensure consistent results from the different laboratories involved in the discovery process. 

The first step in bioassay design is to determine exactly what behavior is to be measured. The next step is to standardize the experimental design and evaluate the significance of potential endogenous and exogenous sources of variation. 

Another problem with free-flight bioassays is that captive insects may be less discriminating than unconfined insects. This may result from a number of mechanisms, but two of primary importance in bioassay design are (1) the absence of normal continuity and transitions between multiple behavioral events (e.g., transition from flight to postalighting behaviors), and (2) unnaturally high oviposi-tional motivation in captive insects that are not allowed to oviposit between trials. Both mechanisms would tend to reduce the ability of laboratory insects to discriminate compared to insects under natural conditions. The first mechanism... 

---