Bioelectricity

Anand M, Khanna RN, Gopal K, et al. 1980b. Effect of endosulfan in bioelectrical activity of brain in rats. Vet Hum Toxicol 22 385-387. 

One of the main determinants of the number of subjects required to reach the desired statistical power is the precision of the measurement tool utilized. More precise measurements will reduce the number of subjects required. As an example, if a study is being conducted to assess the influence of a dietary supplement on body fat, several measurement tools could be used to assess this outcome. These tools range from low levels of cost and precision (e.g. skinfold measurements) to moderate levels (e.g. bioelectrical impedance) to high levels of cost and precision (dual x-ray absorptiometry - DXA). A study that uses skinfold measurements to measure the outcome will require many more subjects than one which employs DXA. Therefore, it is often less expensive in total to utilize a more expensive measurement tool, because the more precise tool will allow the study to have sufficient power with a smaller number of subjects. 

Williams, R. J. P., A general approach to bioelectrics, in Charge and Field Effects in Biosystems (Eds M. J. Allen and P. N. R. Usherwood), Abacus Press, London, 1984. 

Table 3 Bioelectrical Properties of the Albino Rabbit Cornea and the Pigmented Rabbit Conjunctiva...

Koncki R., Mohr G., Wolfbeis O.S., Enzyme sensor for urea based on novel pH bulk optode membrane, Biosens. Bioelectr. 1995 10 653-659. 

Andreou V., Clonis Y., A portable fiber-optic pesticide biosensor based on immobilized cholinesterase and sol-gel entrapped bromocresol purple for in-field use, Biosens. Bioelectr. 2002 17 61-69. 

Jia J., Tang M., Chen X., Qi L., Dong S., Co-immobilized microbial biosensor for BOD estimation based on sol-gel derived composite material, Biosens. Bioelectr. 2003 18 1023-1029. 

S. Kintzios, E. Pistola, P. Panagiotopoulos, M. Bomsel, N. Alexandropoulos, F. Bern, G. Ekonomou, J. Biselis, and R. Levin, Bioelectric recognition assay (BERA). Biosens. Bioelectron. 16, 325-336 (2001). 

S.A. Jaffari and A.P.F. Turner, Novel hexacyanoferrate(III) modified graphite disc electrodes and their application in enzyme electrodes.1. Biosens. Bioelectr. 12,1—9 (1997). 

J.G. Guan, Y.Q. Miao, and J.R. Chen, Prussian blue modified amperometric FIA biosensor one-step immunoassay for alpha-fetoprotein. Biosens. Bioelectr. 19, 789-794 (2004). 

Anthropometric measurements are gross measurements of body cell mass used to evaluate LBM and fat stores. The most common measurements are weight, height, limb size (e.g., skinfold thickness and midarm muscle, wrist, and waist circumferences), and bioelectrical impedance analysis (BIA). 

Pavlenko, V. B., Evstafyeva, I. A., Evstafyeva, E. V., Artov, A. M. (2000). Psychological features and parameters of bioelectrical activity of a brain at the teenagers in connection with the content of mercury in organism. Tavricheskiy medico-biologichesky vestnik, 4, 3 4, 121-125. 

The rat skin TER assay enables to reliably discriminate between skin corrosives and noncorrosive substances [148], The assay relies on the change in the bioelectrical properties of the skin in response to the application of test chemicals. For the measurements, small discs of rat skin are necessary onto which the substances are applied to the epidermal surface for up to 24 h. In... 

Robison TW, Dorio RJ, Kim KJ (1993) Formation of tight monolayers of guinea pig airway epithelial cells cultured in an air-interface Bioelectric properties. Biotechniques 15(3) 468—473. 

Cheek JM, Kim KJ, Crandall ED (1989) Tight monolayers of rat alveolar epithelial cells bioelectric properties and active sodium transport. Am J Physiol 256 (3 Pt 1 ) C688-C693... 

Itil, T.M., The discovery of psychotropic drugs by computer-analyzed cerebral bioelectrical potentials (CEEG), Drug Dev. Res., 1, 373-407, 1981. 

Alvarez, X.A., Mouzo, R., Pichel, V., et al. (1999) Double-blind placebo-controlled study with dticoline in APOE genotyped Alzheimer s disease patients. Effects on cognitive performance, brain bioelectrical activity, and cerebral perfusion. Meth. Find. Exp. Clin. Pharmacol., 21, 633-644. 

Ion-selective electrodes are a remarkable product of this approach. Their development can be followed in several circular pathways from natural bioelectric phenomena to artificial membrane systems and back again, to attempts to explain processes at a cellular level. 

In 1848 du Bois-Reymond [21] suggested that the surfaces of biological formations have a property similar to the electrode of a galvanic cell and that this is the source of bioelectric phenomena observed in damaged tissues. The properties of biological membranes could not, however, be explained before at least the basic electrochemistry of simple models was formulated. The thermodynamic relationships for membrane equilibria were derived by Gibbs in 1875 [29], but because the theory of electrolyte solutions was formulated first by Arrhenius as late as 1887, Gibbs does not mention either ions or electric potentials. 

Nerve cells have two distinct properties that distinguish them from all other types of cells in the body. First, they conduct bioelectrical signals for relatively long distances without any loss of signal strength. Second, they... 

Essentially all nerve cells have one or more projections termed dendrites whose primary function is to receive information from other cells in their vicinity and pass this information on to the cell body. Following the analysis of this information by the nerve cell, bioelectrical changes occur in the nerve membrane that result in the information being passed to the nerve terminal situated at the end of the axon. The change in membrane permeability at the nerve terminal then triggers the release of the neurotransmitter. 

Noble metal connections can reduce the corrosion to an "acceptable" level. This assumption is not true for leads which enter the package from sensors such as micro-electrodes which are characterized by relatively high impedances. The trend for neuroprosthe-tio devices is towards closed-loop control in which the use of high impedance bioelectric sensors will be common. In addition, differing potentials within multi-circuit cables can result in corrosion even when the conductors are fabricated from highly corrosion resistant materials such as MP35N. 

Fig. 17. Bioelectric catalysis on a designed heme protein modified Au electrode. Schematic electron transfer. Reprinted with permission from Ref. (7S7) copyright 1999 American Chemical Society.

Blanchard AP, Kaiser RJ, Hood LE (1996) Biosens Bioelectr 11 687 Gillmor SD, Thiel AJ, Strother TC, Smith LM, LagallyMG (2000) Langmuir 16 7223 Zammatteo N, Jeanmart L, Hamels S, Courtois S, Louette P, Hevesi L, Remade J (2000) Anal Biochem 280 143... 

Ivanova EP, Pham DK, Brack N, Pigram P, Nicolau DV (2004) Biosens Bioelectr 19 1363-1370... 

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