Response differential

Figure 9-1. Differential response of the rate of an enzyme-catalyzed reaction, AV, to the same incremental change in substrate concentration at a substrate concentration ofK (AVa) or far above (AVg).

Cheeran MC, Hu S, Sheng WS, Rashid A, Peterson PK, Lokensgard JR (2005) Differential responses of human brain cells to West Nile virus infection. J Neurovirol 11 512-524 Cudrici C, Ito T, Zafranskaia E, Niculescu F, Mullen KM, Vlaicu S, Judge SI, Calabresi PA, Rus H (2007) Dendritic cells are abundant in non-lesional gray matter in multiple sclerosis. Exp Mol Pathol 83 198-206... 

Kudo FA, Warycha B, Juran PJ, Asada H, Teso D, Aziz F (2005) Differential responsiveness of early- and late-passage endothehal cells to shear stress. Am J Surg 190(5) 763-769 Lee RH, Efron D, Tantry U, Barbul A (2001) Nitric oxide in the healing wound a time-course study. J Surg Res 101(1) 104-108... 

Rainey, F. 1946. Quinine hunters in Ecuador. National Geographic Magazine 89 341-363. Rajakaruna, N., Siddiqui, M. Y., Whitton, J., Bohm, B. A. and Glass, A. D. M. 2003. Differential responses to Na+/K+ and Ca2+/Mg2+ in two edaphic races of Lasthenia californica (Asteraceae) complex A case for parallel evolution of physiological traits. New Phytol. 

Wildlife toxicologists should be attuned to developments in human health mercury, as assays that have been used successfully on humans may be suitable or adaptable for other vertebrate species. Echeverria and co-workers (Echeverria et al. 2005, 2006 Heyer et al. 2006) have characterized a gene encoding coproporphyrinogen oxidase, a gene in the heme biosynthetic pathway. Polymorphism in this gene predicts differential response to elemental mercury exposure in human subjects. Plans to modify this assay for other mercury species in matrices from wildlife are under way. 

Furakawa, T., Kimura, S., Furukawa, N., Bassett, A.L. and Myerburg, R.J. (1991). Role of ATP-regulated potassium channels in differential responses of endocardial and epicardial cells to ischaemia. Circ. Res. 68 1693-1702. 

Fig. 5.11 Output rate from VN epithelia in male mice sexually differentiated responses to male (1.) and to female (2.) urine, [time = sec] -50% neurones preferentially respond to like- or to opposite-sex urine ( 300 x dilution) (from Holy et al, 2000).

Sexually differentiated responses to female-soiled bedding occur within the regions of the AOB only the rostral zone was -activated in males as opposed to that of females the caudal zone cells had no such differential activation VN-x removed the response (Dudley and Moss, 1999 Matsuoka et al., 1999). The number of Fos-ii cells was larger after exposure to females of ICR stain, than to BALB females. Male strain-differences gave equivalent amounts of rostral/caudal activity in females. It is probable that discrimination by females of between-strain chemosignals is related to the fine distinctions possible through the operation of cues related to influence of products from the MHC loci. 

Mucignat-Caretta C., Caretta A. and Baldini J (1998). Protein-bound male urinary pheromones differential responses according to age and gender. Chem Senses 23, 67-70. 

Mallick, B. N., Thankachan, S. Islam, F. (1998). Differential responses of brain stem neurons during spontaneous and stimulation-induced desynchronization of the cortical eeg in freely moving cats. Sleep Res. Online 1, 132-46. 

Poland, R. E., McCracken, J. T., Lutchmansingh, P. et al. Differential response of rapid eye movement sleep to cholinergic blockade by scopolamine in currently depressed, remitted, and normal control subjects. Biol. Psych. 41 929-938,1997. 

Wilson, R.W. and E.W. Taylor. 1993. Differential responses to copper in rainbow trout (Oncorhynchus mykiss) acclimated to sea water and brackish water. Jour. Comp. Physiol. 163B 239-246. 

Hollister, T.A. and G.E. Walsh. 1973. Differential responses of marine phytoplankton to herbicides oxygen evolution. Bull. Environ. Contam. Toxicol. 9 291-295. 

Moraghan T, Antoniucci DM, Grenert JP, Sieck GC, Johnson C, Miller VM, Fitzpatrick LA (1996) Differential response in cell proliferation to beta estradiol in coronary arterial vascular smooth muscle cells obtained from mature female versus male animals. Endocrinology 137 5174-5177... 

An important insight from many studies (28) is that the response patterns—the molecular images—at various levels in the central olfactory pathway are set up by the differential responses of the ORCs in the peripheral receptor epithelium. These studies also suggest that functional modules, which may correspond to recognizable structural units such as individual glomeruli with their associated cells, in the olfactory bulb or lobe participate in the analysis of olfactory information conveyed to them... 

Tabo, J.D. and Paul, W.E. (1973). Functional heterogeneity of murine lymphoid cells. III. Differential responsiveness of T cells to phytohemagglutinin and concanavalin A for T cell subsets. J. Immunol. 110 362-369. 

The PBPK model development for a chemical is preceded by the definition of the problem, which in toxicology may often be related to the apparent complex nature of toxicity. Examples of such apparent complex toxic responses include nonlinearity in dose-response, sex and species differences in tissue response, differential response of tissues to chemical exposure, qualitatively and/or quantitatively difference responses for the same cumulative dose administered by different routes and scenarios, and so on. In these instances, PBPK modeling studies can be utilized to evaluate the pharmacokinetic basis of the apparent complex nature of toxicity induced by the chemical. One of the values of PBPK modeling, in fact, is that accurate description of target tissue dose often resolves behavior that appears complex at the administered dose level. 

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