Using loop gain to assess ventilatory control in obstructive sleep apnea.

For the testing of a person's sense of smell, both subjective and objective methods are available. Subjective tests include odor identification, threshold and discrimination tests. A prerequisite for successful testing is the ability and willingness of the patient to cooperate. For testing smell in the demented, comatose or simulating patient, the measurement of chemosensory evoked potentials (CSEP) is an established method.

Chemoreceptor Cells↗

PubMed2006

Balls and chains--a mesoscopic approach to tethered protein domains.

Many proteins contain regions of unstructured polypeptide chain that appear to be flexible and to undergo random thermal motion. In some cases the unfolded sequence acts as a flexible tether that restricts the diffusion of a globular protein domain for the purpose of catalysis or self-assembly. In this article, we present a stochastic model for tethered protein domains under various conditions and solve it numerically to deduce the general and dynamic properties of these systems. A critical domain size dependent on the length of the tether is presented, above which a spherical domain tethered to an impenetrable wall by a flexible chain displays a restricted localization between two concentric half-shells. Results suggest that the diffusion of such a spherical domain is effectively reduced in its dimensionality and able to explore the available space with high efficiency. It also becomes clear that the orientation of the ball is not independent of the distance from the tethering point but becomes more constrained as the linking tether is extended. The possible biological significance of these and other results is discussed.

Chemoreceptor Cells↗

PubMed2006

[The capsaicin receptor. "TRPing" transduction for painful stimuli].

The capsaicin receptor TRPV1, once discovered as a receptor for pungent spices, is a polymodal sensor molecule for painful chemical and thermal stimuli. However, TRPV1 plays an important role not only for the integration of acute painful stimuli but also in the genesis of inflammatory processes. The persistent functional sensitization of TRPV1 as well as an up-regulation of its expression may contribute to the development and maintenance of chronic pain states. Thus, TRPV1 is an excellent target for a rational pharmacological treatment of pain. Several additional physiological and pathophysiological functions of TRPV1 are assumed beyond nociception and pain. Activation of TRPV1 seems to contribute to the etiology and pathogenesis of inflammatory diseases concerning, e.g., the gastrointestinal tract, the bladder, and the respiratory system. Therefore, the therapeutic potential of a pharmacological manipulation of TRPV1 may not be restricted to a symptomatic therapy of pain.

Chemoreceptor Cells↗