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Human physiology, hazards and health risks
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2023
Revati Phalkey, Naima Bradley, Alec Dobney, Virginia Murray, John O’Hagan, Mutahir Ahmad, Darren Addison, Tracy Gooding, Timothy W Gant, Emma L Marczylo, Caryn L Cox
Sympathetic nerve fibres can cause either contraction or relaxation of the smooth muscle of the innervated structure. The receptors, which cause contraction as a response are alpha receptors and those that cause dilatation are beta receptors. These can be blocked selectively by either alpha or beta blockers. Blockade of beta receptors in the heart decreases the force with which the heart muscle contracts and is used to reduce blood pressure. Blocking the effects of alpha receptors on blood vessels, arterioles, where there is maximal resistance to blood flow would cause a fall in blood pressure. Alpha blockers are thus used to treat high blood pressure. Stimulation of beta receptors in the airways is used in the treatment of asthma to dilate or increase the lumen through which air can move in the small airways or bronchioles of the lung. In addition, there are ganglion-blocking drugs that block transmission at the sympathetic ganglia, which are also used to treat very high blood pressure in cases of emergency.
Designing for Upper Torso and Arm Anatomy
Published in Karen L. LaBat, Karen S. Ryan, Human Body, 2019
Three kinds of specialized sympathetic nervous system structures are located at variable distances from the spine. These structures, which carry out specific transmission activities, include: (a) sympathetic ganglia—clusters of sympathetic nervous system cells, (b) connected sympathetic ganglia, the sympathetic chain, also called the sympathetic trunk (refer to Figure 4.25), and (c) sympathetic nerve plexuses which connect the internal organs to the CNS. Just as they carry somatic (sensory and motor) nerve fibers, the thoracic spinal nerve roots and the pairs of thoracic spinal nerves they form (plus the first two lumbar spinal nerve roots/nerves) carry sympathetic nervous system fibers between the spinal cord and the sympathetic ganglia. From the sympathetic ganglia, lying close to the vertebral bodies, the nerve fibers connect to components farther out in the body (other sympathetic nervous system cells, blood vessels, sweat glands, and internal organs). The sympathetic chain, like the thoracic spinal cord, is protected from all but extreme trauma. Many implantable devices have been developed to stimulate or block nerve signal transmission at sympathetic nervous system structures (Stanton-Hicks & Salamon, 1997). Non-invasive wearable options may also be possible.
Human physiology, hazards and health risks
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2016
David J. Baker, Naima Bradley, Alec Dobney, Virginia Murray, Jill R. Meara, John O’Hagan, Neil P. McColl, Caryn L. Cox
Sympathetic nerve fibres can cause either contraction or relaxation of the smooth muscle of the innervated structure. The receptors, which cause contraction as a response, are alpha receptors and those that cause dilatation are beta receptors. These can be blocked selectively by either alpha or beta blockers. Blockade of beta receptors in the heart decreases the force with which the heart muscle contracts and is used to reduce blood pressure. Blocking the effects of alpha receptors on blood vessels, arterioles, where there is maximal resistance to blood flow would cause a fall in blood pressure and are thus used to treat high blood pressure. Stimulation of beta receptors in the airways is used in the treatment of asthma to dilate or increase the lumen through which air can move in the small airways or bronchioles of the lung. In addition there are ganglion-blocking drugs that block transmission at the sympathetic ganglia, which are also used to treat very high blood pressure in cases of emergency.
Theranostic approaches in nuclear medicine: current status and future prospects
Published in Expert Review of Medical Devices, 2020
Luca Filippi, Agostino Chiaravalloti, Orazio Schillaci, Roberto Cianni, Oreste Bagni
Neuroblastoma (NB) represents the most common solid tumor in children, arising from the embryonic sympathoadrenal lineage of the neural crest, almost exclusively occurring in children. Although it is a relatively rare disease with an incidence of 1 case on 8000 live births, it accounts for about the 13% malignancy-related death in pediatric patients [22]. Neuroblastoma can arise everywhere along the sympathetic system, but the most frequent localizations are represented by the sympathetic ganglia in abdomen and by the medullary portion of the adrenal glands. According to The Children’s Oncology Group (COG), NB is stratified in low, intermediate, and high-risk on the basis of several biological and clinical factors [23]. Despite many advances in therapeutic approaches, prognosis in high-risk NB remains poor.