Estimation of Biological Activity

A main topic in molecular pharmacology deals with the interaction between a receptor molecule and an agonist, either alone or in the presence of a competing antagonist. In a simple case, one molecule of agonist binds reversibly to a receptor 

FIGURE 6.29 Schematic view of a CPG neural network trained with vector pairs. The input vector consists of ten countrates for major elements in rock samples, whereas the output vector contains the interelement coefficients p for all major elements. After training, the network is able to predict the interelement coefficients for the given sample matrix. 

---

Ostroumov, S.A. Some aspects of the estimation of biological activity of xenobiotics. Bulletin of Moscow University 1990, 2, 27-34. 

The PASS estimations of biological activity spectra of new compounds are based on the Structure-Activity Relationships data and knowledge-base (SAR Base), which accumulates the results of the training set analysis. The in-house... 

The process of drug discovery relies on the testing of molecules in systems to yield estimates of biological activity in an iterative process of changing the structure... 

Bioassays Any quantitative estimation of biologically active substances by measurement of the magnitude of their actions on living organisms or parts of organisms. 

Fig. 13.1 An ideal activity landscape. In such landscapes, which are conceptually similar to the gently rolling Flint Hills of Kansas depicted in the figure, it is generally assumed that similar molecules have similar biological activities [3]. It is clear from the figure that even relatively sparse sampling of chemistry space may be sufficient to construct a reasonable estimate of the activity landscape.

CM80nm, respectively) as peaks related to the component type of humic-like substances [1 (excitation at 310-320 nm and emission at 38(M20nm) as a peak related to the component type of marine humic-like substances y (excitation at 270-280 nm and emission at 300-320 nm) as a peak related to the component type of tyrosine-like and/or protein-like 8 (excitation at 270-280nm and emission at 320-350 nm) as a peak related to the component type of tryptophane-like, proteinlike, and/or phenol-like substances. Parlanti et al. (2002) used the p and y peaks as markers to estimate the biological activity in coastal zones and the different stages of the biological production. 

Dissolved oxygen (DO) concentration is a key variable in the operation. It affects the economy and is also closely related to the biological activity of the organisms in the sludge. The main emphasis in this paper is to show how the DO concentration distribution in a non-homogeneous aerator can be used for the estimation of the activity of both heterotrophic and nitrifying organisms. 

Olsson, G. Andrews, J.F. "Estimation and control of biological activity in the activated sludge process using dissolved oxygen measurements" Proc. IFAC Symp. Environmental Systems Planning, Design and Control, Kyoto, Japan, 1977. 

Gel filtration in its various forms is an efficient tool for preparations in protein chemistry. It can also be used to test the supposed homogeneity of a protein or peptide preparation. A gel column calibrated with respect to its molecular-sieving properties may also be used to estimate the molecular size of biologically active or otherwise labeled substances before their isolation has been accomplished. Needless to say, the result of such an estimation must be cautiously interpreted. 

The computer program PASS was designed to predict many kinds of biological activity simultaneously based on the structural formulae of chemical compounds. Thus, PASS may estimate the biological activity profiles for virtual molecules, prior to their chemical synthesis and biological testing. 

Leave one out cross-validation for 3300 kinds of biological activity and 117 332 substances provides the estimate of PASS prediction accuracy during the training procedure. The average accuracy of prediction is about 94.7% according to the LOO CV estimation, while that for particular kinds of activity varies from 65% [System lupus erythematosus treatment, Immunomodulator (HIV)] to 99.9% (Allergic rhinitis treatment, histone acetylation inducer). The estimated accuracy of prediction for all kinds of biological activity predicted by PASS is presented at the web site. " ... 

The current worldwide supply for custom-made peptides is estimated to be around 10 billion (this amount includes pharmaceutically important peptides). Principal components of the market are peptides for studies of protein-protein interactions, finding antibody epitopes, and analogs of biologically active peptides and potential drugs. Added to this market is a significant business in peptide synthesizers, reagents, and supports. Large-scale proteomics research is... 

These numbers are not merely speculative estimates. The ratio 1 1000 is typical and considered reasonable Tor many studies oriented toward the creation of biologically active compounds. 

---