Multiple stimuli

NF-/< B is stimulated by multiple stimuli within stressed cells of different origin to form part of a protective response (Baichwal and Baeuerle, 1997) (Table 7.3). Upon stimulation LB is rapidly phosphorylated, ubiquinated, and then degraded by proteasomes resulting in the release and subsequent nuclear translocation of active NF-/cB. 

The use of rumble strips on highways to prevent sleepiness-related accidents represents the clearest example of society adapting a countermeasure. Rumble strips combine multiple stimuli (i.e., noise, cutaneous stimulation) in an attempt to arouse the driver and prevent accidents. Like the other countermeasures discussed, there is no question about its acute effectiveness. There is a decrease in accidents proximal to the rumble strip. However, a question remains about its overall efficacy. Some research has described a phenomenon called migration, the movement of accidents from the location of the rumble strips to other locations on the highway. The question yet to be resolved is whether rumble strips prevent accidents or merely postpone them. 

With cell retention accomplished by 3D flow control, calcium mobilization in a single yeast cell has been studied over a long period of time, and in the manner of multiple stimuli and multiple responses. Loading of the Ca2+- sensitive dye Fluo-4 in the cell was accomplished either (1) after cell wall removal or (2)... 

Other methods for measurement of memory function rely on explicit discrimination tasks. The matching to sample task described earlier is one example. In this paradigm, a sample stimulus is presented briefly to the subject. The subject must then pick the sample stimulus when subsequently presented with multiple stimulus options (i.e., the subject must match the sample). When delay intervals are imposed between the presentation of the sample stimulus and the subsequent presentation of multiple stimuli, the task becomes a memory task. In this case, the subject must remember the sample stimulus in order to perform correctly. As in the delayed alternation procedure. 

IL-4 and IL-10 are inhibitors of IL-1 synthesis, as are glucocorticoids that are produced in response to IL-1, and may represent a feedback mechanism of IL-1 secretion. Multiple, stimuli are likely to operate in vivo to promote IL-Ip posttranslational processing, such as anion transport inhibitors. ... 

Multiple stimuli for the release of gastric acid exist, so blockade of the histamine receptor only decreases secretion to the extent that other stimuli are present or absent. Proton-pump inhibitors act at the last step of gastric acid synthesis and thus are not subject to the effects of other mediators. 

The pathways of metabolism have multiple control points and multiple regulators at each control point. The function of these complex mechanisms is to produce a graded response to a stimulus and to provide sensitivity to multiple stimuli so that an exact balance is maintained between flux through a given step (or series of steps) and the need or use for the product. Pyruvate dehydrogenase is an example of an enzyme that has multiple regulatory mechanisms. Regardless of insulin levels, the enzyme cannot become fully activated in the presence of products and absence of substrates. 

How crustaceans respond to chemical cues of elevated predation risk can be influenced by a variety of factors (see Fig. 18.2). Animals are always detecting multiple stimuli in a number of sensory modalities and those inputs can clearly alter responses to chemical danger cues. When the crayfish Pacifastacus leniusculus was exposed to both visual and chemical cues associated with predation risk, the reduction in locomotion and increase in shelter use was greater than when either stimulus was presented alone (Blake and Hart 1993). Detection of multiple cues related to increased predation risk clearly can be an indication of greater probability of predatory activity. 

The chemotaxis genes of E. coli are listed in Table 10. They include the genes identified by the groups of mutants that are nonchemotactic for multiple stimuli and for all the stimuli, as well as flagellar genes that are involved in regulating the direction of flagellar rotation. The... 

Integrated migration to multiple chemoattractants has been demonstrated, and the mechanism by which this occurs likely involves receptor desensitization. Using multiple combinations of pairs of chemoattractants, it has been shown that receptor desensitization or adaptation give the cell a memory of prior exposure, and this may influence how the cells respond to multiple stimuli. Chemoattractants... 

Kitayama J, Carr MW, Roth RJ, Buccola J, Springer TA. Contrasting responses to multiple stimuli in transendothelial migration. J Immunol 1997 158 2340-2349. 

Stimulation may be done with the same electrode designs either transcutaneous right above the bundle of interest, or by needles. Muscles, for example, in the hand are stimulated by stimulating efferent nerves in the arm. EMG electrodes can pick up the result of this stimulation, for instance for nerve velocity determination. It can also be picked up by neurographic electrodes, but the signal is much smaller and must therefore be averaged with multiple stimuli. However, the method is more interesting because there is more information in the response waveforms. 

Depending on the nature of the grafted chains, the membrane-brush system responds to a specific type of stimulus. Known types of stimuli-responsive polymers are PAA, which has a transition between the collapsed and swollen state around pK , and PNlPAAm, which has a pronounced tendency to swell and deswell as a function of temperature. Essentially numerous combinations can be envisioned for the fabrication of concave brushes with diverse properties, including multiblock grafted polymers [45] or mixed brushes that are sensitive to multiple stimuli [36]. 

SI-IMP has been used for synthesis of different types of stimuli-responsive polymer brushes that are responsive to several external stimuli, such as pFI, temperature, and ionic strength [28,58-65]. Because materials interact with their surroundings via their interfaces, the ability to fashion soft interfacial layers and tune the range, extent, and type of physicochemical interactions across interfaces is central to a variety of applications. Rahane et al. carried out sequential SI-IMP of two monomers to create bilevel poly(methacrylic acid)-Woc/c-poly(N-isopropylacrylamide) (PMAA-b-PNIPAM) block copolymer brushes that can respond to multiple stimuli [28]. They observed that each strata in the bilevel PMAA-b-PNIPAM brush retained its customary responsive characteristics PMAA being a "weak" polyelectrolyte swells as pH is increased and the thermoresponsive PNIPAM block collapses as temperature is raised through the volume phase transition temperature due to its lower critical solution temperature (LCST) behavior. As a result of ions added to make buffer solutions of various pH and because of the effect of surface confinement, the swollen-collapse transition of the PNIPAM layer occurs at a... 

Costa, R. R., Custodio, C. A., Arias, F. J., Rodriguez-Cabello, J. C. and Mano, J. F. (2011). Layer-by-layer assembly of chitosan and recombinant biopolymers into biomimetic coatings with multiple stimuli-responsive properties. Small, 7, 2640-2649. 

Vascular tissue is exposed to multiple stimuli that influence the activities of oxidases that produce ROS and metabolic conditions that influence the control of redox systems that influence both the metabolism of individual oxidant species and/or the expression of signaling regulated by these species. Changes in PO2 can influence both the release of vasoactive mediators from the endothelium and processes contained within vascular smooth muscle through changes in ROS. These interactions create an environment for the existence of a wealth of PO2 sensing and signaling mechanisms in the vessel wall. 

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