Biochemical circuits

Development of artificial biochemical circuits based on nucleic acids can help researchers understand the mechanisms of complex biological systems, and design strategies for various requirements [57]. Operation of such circuits can be verified by conducting MS... 

Wallimann, T., Wyss. M., Brdicza, D., Nicolay, K.. Eppenberger, H.M. (1992). Intracellular compartmentation. structure and function of creatine kinase isoenzymes in tissues with high and fluctuating energy demands The phosphocreatine circuit for cellular energy homeostasis. Biochem. J. 281,21-40. 

Microelectronic circuits for communications. Controlled permeability films for drug delivery systems. Protein-specific sensors for the monitoring of biochemical processes. Catalysts for the production of fuels and chemicals. Optical coatings for window glass. Electrodes for batteries and fuel cells. Corrosion-resistant coatings for the protection of metals and ceramics. Surface active agents, or surfactants, for use in tertiary oil recovery and the production of polymers, paper, textiles, agricultural chemicals, and cement. 

KR Page. (1980). The use of KC1 salt bridges in electrophysiological circuits. Comp Biochem Physiol A67 637-642. 

It may be that any peripherally adversive stimulus — especially one that stimulates sympathetic activity — thus has the potential to activate brain areas of prime importance in the formation of anxiety symptoms. As a result of pharmacological challenge studies, biochemical assays, neuroimaging and studies of animal models, a number of centrally acting neurotransmitters, and their relevant neural circuits, are implicated in anxiety. These neurotransmitters include norepinephrine, serotonin, GABA, neuropeptide Y, cholecystokin and substance P. 

J. J. Tyson and H. G. Othmer, The dynamics of feedback control circuits in biochemical pathways. Progr. Theor. Biol. 5, 1 62 (1978). 

Biochemical lesions that induce depressive syndromes include such classic examples as Parkinson s and Huntington s diseases, especially early in their courses. These disorders involve derangements of central amine systems (i.e., in Parkinson s, there is a disturbance in both dopamine and norepinephrine in Huntington s, dopamine is affected, as well as other nonbiogenic amine neural circuits). Furthermore, antidepressants and ECT, which potentiate central neurotransmission, have effectively relieved depression associated with Parkinson s disease. 

Micro flow control devices open new possibilities for the miniaturization of conventional chemical and biochemical analysis systems. The micro total analysis system (pTAS) including microfabricated detectors (e.g. silicon based chemical sensors, optical sensors), micro flow control devices and control/detec-tion circuits is a practical micro electro mechanical system (MEMS). pTAS realize very small necessary sample volume, fast response and the reduction of reagents which is very useful in chemical and medical analysis. Two approaches of monolithic and hybrid integration of these devices have been studied. Monolithic and hybrid types of flow injection analysis (FIA) systems were already demonstrated [4, 5]. The combination of the partly integrated components and discrete components is useful in many cases [6]. To fabricate such systems, bonding and assembling methods play very important roles [7]. 

In a more technical vein, Miller excitedly announced that some components of IC biochemical systems I discuss have other roles in the cell, such as the ciliary proteins tubulin and dynein.11 But I myself pointed that out when I first wrote Darwin s Black Box ten years ago For example, in Chapter 3 I wrote that microtubules occur in many cells and are usually used as mere structural supports, like girders, to prop up cell shape.12 Furthermore, motor proteins also are involved in other cell functions, such as transporting cargo from one end of the cell to another. Nonetheless, I emphasized that such other roles don t help with the irreducible complexity of the cilium an evolutionary story for the cilium must envision a circuitous route, perhaps adapting parts that were originally used for other purposes to build a cilium. And I went on to show why indirect routes are quite implausible.13 Toothpicks do not... 

Mohler H, Fritschy JM, Crestani F, Hensch T, Rudolph U. 2004. Specific GABA(A) circuits in brain development and therapy. Biochem Pharmacol 68 1685-1690. 

A central question in cellular biology is now to elucidate (meaning to develop models with reliable predictive power) the mechanisms by which the cells transduce information and perform their functions. Cellular biochemical signaling systems are customarily visualized as logic circuits the components for the circuitry, now popularly called modules [78], consist of molecules and biochemical reactions. Hence they can be subjected to kinetic and thermodynamic analysis as we have introduced in the previous chapters. In this chapter, we study several such modules that occur widely in cellular biology. 

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