Biological systems signaling

Biomarkers are broadly defined as indicators signaling events in biologic systems or samples. They have been classified as markers of exposure, markers of effect, and markers of susceptibility (NAS/NRC 1989). 

A cell subjected to a stress of any kind can potentially exhibit a wide range of responses. Severe stress may lead to cell death and, ultimately, to cell lysis imposition of less severe conditions may result in a metabolically perturbed system, which may either revert to its initial state or adapt in some way to the imposed conditions. Figure 10 shows a hypothetical scheme, presented by Prokop and Bajpai [12], for the signal-response cascade associated with hydrodynamic shear stress. The signal reception/transduction mechanisms are, as yet, poorly understood. While Fig. 10 can be applied to any biological system, Namdev and... 

BIOLOGIC SYSTEMS EXHIBIT THREE TYPES OF TEMPORAL RESPONSES TO A REGULATORY SIGNAL... 

In Table 10 there are some examples of EPR signals obtained from metallo-proteins. Most of this work has been conducted at low temperatures and it is now necessary to develop probes which contain metals and which will give signals at room temperature, e.g. d1 complexes. Such a label could be of use in many explorations of activity in biological systems. 

If the solute concentration is very low, this signal can become very strong investigations on biological systems are often carried out in 1 1 mixtures of H20 and D20, and spectrum (c) shows that if we do this for our model compound we see no signal from the dissolved molecules ... 

---