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Bioinformatics Analysis of Dysfunctional (Mutated) Proteins of Cardiac Ion Channels Underlying the Brugada Syndrome
Published in Qurban A. Memon, Shakeel Ahmed Khoja, Data Science, 2019
Carlos Polanco, Manlio F. Márquez, Vladimir N. Uversky, Thomas Buhse, Miguel Arias Estrada
Sodium channel subunit beta-1 (SCN1B, UniProt ID: Q07699), mutations in SCN1B gene are associated with generalized epilepsy with febrile seizures plus 1 (GEFS+1), BrS 5 (BRGDA5), familial atrial fibrillation, 13 (ATFB13), and epileptic encephalopathy, early infantile, 52 (EIEE52).
Sedation, analgesia and patient observation in interventional radiology
Published in William H. Bush, Karl N. Krecke, Bernard F. King, Michael A. Bettmann, Radiology Life Support (Rad-LS), 2017
Jeffrey E. Quam, Michael A. Bettmann
Local anesthetics interfere with the sodium channels of the nerve-cell membrane. Under normal circumstances, a slight depolarization of the cell membrane generates a large transient increase in the permeability of the membrane to sodium. By blocking this rapid influx of sodium, local anesthetics increase the threshold of excitability and blunt the rate of increase in action potential. These factors thus decrease the probability of propagation of an action potential along the nerve fiber. The sodium channel must be active and open to allow the anesthetic to interfere with the channel’s function. Although local anesthetics are non-specific nerve depressants (motor, sensory or autonomic), sensory nerve function is blocked earliest, because sensory neurons are the most rapidly firing type. Lidocaine was introduced in 1948 and is currently the most commonly used local anesthetic.26 It replaced procaine partly as a result of the decreased incidence of anaphylactoid reactions associated with its use. Lidocaine also provides a more prolonged anesthesia than does procaine.
Movement Control (Muscular Physiology)
Published in Emeric Arus, Biomechanics of Human Motion, 2017
The soma contains the nucleus and other cellular organelles. The dendrites are typically short, branched, and are thin extensions of the cell body that receives the excitation. The axon is a long, slender part of the cell body that sends nerve impulses. It arises from the cell body at the axon hillock. At this place, the density of sodium channels is very high, so this is the place where action potentials are generated.
A bulk-driven, buffer-biased, gain-boosted amplifier for biomedical signal enhancement
Published in Cogent Engineering, 2019
Sarin Vijay Mythry, D. Jackuline Moni
When neurons depolarize, Na+ (sodium) channels rapidly open and shift the membrane potential towards the equilibrium potential of sodium. As leakage channels are open at rest, there is a balance between leakage currents and Na+ channels opened at depolarization, but at a specific point, Na+ current exceeds the leakage current, membrane potential at this state is called the threshold potential. However, as Na+ depolarization opens voltage gated K+ channels; the membrane potential overshoots 0 mV and then rapidly returns to resting membrane potential after a transient undershoot. This rapid change occurs over several milliseconds and is called as an Action potential (or commonly as Sodium spike) and this propagates along the length of the axon. At the axon terminal, the spike provides Ca2+ opening depolarization and the resultant release of neurotransmitters which excite another neuron and thereby communicating information (Sadock et al., 0000). Figure 4 depicts the depolarization and repolarization wave in a nerve cell (Sadock et al., 0000).
Mechanism of peripheral nerve modulation and recent applications
Published in International Journal of Optomechatronics, 2021
Heejae Shin, Minseok Kang, Sanghoon Lee
Let’s look deeper at the simple principle with an example of activating a single axon using a monopolar electrode and cathodic current (Figure 2(a)). When a cathodic current is emitted from a single electrode adjacent to the axon, the electrical potential outside the cell in the area adjacent to the electrode becomes negative, and thereby the inside of the cell in the adjacent area becomes relatively positive. By these phenomena, if the membrane potential becomes sufficient to exceed the threshold of the axon, the pores of the voltage-gated sodium channel open, and a series of processes for generating a general action potential is carried out.[32]
Studies on local anesthetic lidocaine hydrochloride delivery via photo-triggered implantable polymeric microneedles as a patient-controlled transdermal analgesia system
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Yafeng Li, Xiaoxiang Liao, Bin Zheng
Local anaesthetics have been used to control pain-related issues that block the impulse initiation and transmission processes in the axons by blocking voltage-dependent sodium channels. Generally, local anaesthetics are divided into two major chemical classes: amino esters and amino amides. Amino esters are metabolised by plasma esters, whereas amino amides are metabolised in the liver by hepatic enzymes [6]. Lidocaine hydrochloride, the most frequently used local anaesthetic in the amide group, is widely used in various fields of medicine [7, 8]. In addition, lidocaine hydrochloride has a very short half-life (60–120 min) and a low level of toxicity [9, 10].