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Macrocyclic Receptors for Biomolecules and Biochemical Sensing
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
Recognition and sensing are the fundamental processes in nature. One has five sensing organs, i.e., the nose, tongue, ears, eyes and skin. Among these, ear, eyes and skin are perceived to be physical sensors as they detect physical sensations of sound, light and heat, etc., respectively. In contrast, the nose and tongue are chemical sensors where the sense of smell and taste is perceived through chemoreceptors by complicated mechanism. Although the nose or tongue as sense organs cannot quantify the concentration of a particular chemical that is being sensed the biorecognition property of these can provide a guiding principle in the development of artificial sensing systems for the identification and measurement of biomolecules. Since detection of biologically important molecules specifically biomolecules are very important in catalysis, drug delivery, surface immobilization and sensing a small section of cavitands, namely, cyclodextrins, cyclophanes, cucurbiturils, and molecular tweezers, which display specific, well-characterized recognition properties toward biomolecules (nucleic acid, carbohydrates, proteins and lipids) are described here.
Human and Biomimetic Sensors
Published in Patrick F. Dunn, Fundamentals of Sensors for Engineering and Science, 2019
A stimulus can be characterized by its energy, location, intensity, and duration. Human sensory receptors respond to mechanical, chemical, thermal, and electromagnetic energy, as presented in Table 3.1. These are called mechanoreceptors, chemoreceptors, thermoreceptors, and photoreceptors, respectively. The stimuli of chemoreceptors are molecules that bind to the receptor site. Stimuli include oxygen, hydrogen (thus, pH), and more complex molecules. Mechanoreceptor stimuli are strain, vibration, acceleration, pressure, and sound. Light photons (electromagnetic energy) stimulate photoreceptors. Thermoreceptors are stimulated by temperature and changes in temperature. Each sensor description, its signal pathway, and sensor characteristics are presented in the following.
Biological Responses in Context
Published in Arthur T. Johnson, Biology for Engineers, 2019
Animal respiration is usually less sensitive to oxygen lack than it is to the presence of carbon dioxide. There are both carbon dioxide and oxygen chemoreceptors in the body, but the carbon dioxide-sensitive receptors have a greater effect on respiratory adjustments to exercise and atmospheric changes. In the presence of hyperbaric oxygen, however, the response to carbon dioxide may be eliminated entirely. When this happens, continuously produced carbon dioxide can build up to the point where cranial vasodilation can cause coma, convulsions, and even death. In addition, hyperbaric oxygen can cause pulmonary irritation, congestion, exudation, and edema. Central nervous systems are affected by the inactivation of certain enzymes as a direct result of the high levels of oxygen in the blood. Very high dissolved oxygen concentrations in ecosystems is also toxic to some cells.
Intra-carotid body inter-cellular communication
Published in Journal of the Royal Society of New Zealand, 2023
Liam P. Argent, Aabharika Bose, Julian F. R. Paton
Type I cells and petrosal afferents collectively release several neurotransmitters NO (Wang et al. 1993; Del Rio et al. 2011) and ATP (Buttigieg and Nurse 2004; Grygorczyk and Orlov 2017; Buvinic et al. 2002) as well as ACh (Zhang et al. 2000) and noradrenaline (Gomez-Niño et al. 1990; Schamel and Verna 1992) known to stimulate or inhibit vascular smooth muscle and so it may be that parenchymal cells engage in paracrine communication with the local vasculature and that this modulates carotid body perfusion with consequences for chemoreceptor sensitivity and ultimately petrosal afferent firing (Figure 1).