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Rehabilitation Computing in Electronic Computing
Published in Parveen Berwal, Jagjit Singh Dhatterwal, Kuldeep Singh Kaswan, Shashi Kant, Computer Applications in Engineering and Management, 2022
Parveen Berwal, Jagjit Singh Dhatterwal, Kuldeep Singh Kaswan, Shashi Kant
The patch-clamp methodology has been successfully used to study cellular ion channels. The practice is accomplished of sensing streams flowing in/out of the cell concluded a single ion network at peak resolution. The dysfunction of ion channels has now been shown to be the cause of a variety of diseases. The patch-clamp system can be used to study the operation of different ion channels under various physical and chemical stimulations, as well as cell communications, and these experiments can help one better understand the fundamentals of cells. Patch clamping involves isolating a patch of membranes from the extracellular environment with a glass Pasteur pipette to record the current running into the region. Glass micropipettes with a tip diameter of 1–2 m are created by heating and pulling small glass capillaries. After that, the capillary tubes are backfilled with an electrical conductor and rubbed against a surface of cells. A soft suction is applied to the pipette’s backend to increase the sealing state. In the enzyme immobilization setup, there are different attributes: monitoring electrodes within the pipette and a buffer solution in the bath solution, as shown in A resistive element seal between both the crystal and the membrane patch is done to avoid single cell membrane current flow of the order of a few Pico Amperes. The increased resistance seal decreases current flow between the metal conductors, finishes the membrane patch’s electrical separation, and lowers recording current noise. The seal is known as a giga-seal because its thermal conductivity is in the gig ohm range.
Nanoscale electrokinetic phenomena
Published in Zhigang Li, Nanofluidics, 2018
Voltage-gated ion channels are quite common and play critical roles in physiological functions of certain biological systems, such as nerve, muscle, and neuroendocrine cells. Under a transmembrane potential, voltage-gated ion channels can undergo conformational changes or surface property variations to control the opening and closing of the channel. Voltage-gated ion channels are also ion selective. According to ion selectivity, they are classified into voltage-gated K+ channels, Na+ channels, Ca2+ channels, and Cl− channels. Artificial nanochannels with similar voltage gating and ion selectivity properties possess promising potentials in many applications, such as functional nanodevices, drug delivery, and biodetection.
Electrophysiology
Published in Jay L. Nadeau, Introduction to Experimental Biophysics, 2017
Jay L. Nadeau, Christian A. Lindensmith, Thomas Knöpfel
Electrophysiology is a mainstay of biophysics; some may argue that it is what made biophysics exist. There are many reasons to perform electrophysiology, among them are as follows: to examine excitable cells to determine the factors controlling and altering their excitability; to clone and characterize new ion channels; to determine the effect of transfected ion channels on cell properties; to study the mechanisms of selectivity and/or gating; and to examine the effect of chemical species on ligand-gated ion channels for discovery of new drugs. The latter is a field of research unto itself, as drugs that affect ion channels include anesthetic agents, antidepressants, anticonvulsants, and classic drugs of addiction such as nicotine; other ion channel agents are commonly known poisons such as muscarine (found in some poisonous mushrooms), organophosphates, war gases known as “nerve gas,” and many more.
Plant pharmacology: Insights into in-planta kinetic and dynamic processes of xenobiotics
Published in Critical Reviews in Environmental Science and Technology, 2022
Tomer Malchi, Sara Eyal, Henryk Czosnek, Moshe Shenker, Benny Chefetz
There are numerous examples of analogies and homologies of receptors between animals and plants, and examples of such are transmembrane ion-channel receptors, transmembrane G-protein-coupled receptors and transmembrane receptors within cytosolic domains. Transmembrane ion-channel receptors such as voltage-gated ion channels regulate the ionic balance of the cell and cellular processes. Plant ion channel families exhibit homologies to animal proteins, and include hyperpolarization-and depolarization-activated Shaker-type potassium channels, chloride transporters/channels, cyclic nucleotide–gated channels, and ionotropic glutamate receptor homologs (Ward et al., 2009). Transmembrane G-protein-coupled receptors can activate a signal-transduction pathway that alters cellular processes through the activation of a second messenger system. Heterotrimeric G protein signaling regulates a wide range of growth and developmental processes in both animals and plants, but the two kingdoms are believed to have differences in protein structure, subunit composition and different G-protein-associated receptors (Stateczny et al., 2016; Trusov & Botella, 2016);
A bulk-driven, buffer-biased, gain-boosted amplifier for biomedical signal enhancement
Published in Cogent Engineering, 2019
Sarin Vijay Mythry, D. Jackuline Moni
Human body has an intricate network which is spread across the body and is controlled by the centers in the Brain and the Spinal cord. It is this nerve network which conveys the action commands from the control centers and in return gathers feedback information from various parts of the body via electro-chemical mechanisms. The unit of this elaborate nerve network is called a neuron. Neuron is a cell which has a cell body, dendrites, and an axon. Neurological and psychiatric disorders might be due to changes in inter-neuron information transfer and changes in the excitability of the neurons. Epilepsy is an example of a disease due to abnormal neuronal excitability. The information is transferred between neurons in the form of electrical signal which result from the flow of chemical ions across the cell membrane through ion channels. There are broadly two types of ion channels; they are leakage channels and voltage-gated channels. The leakage channels are open at rest and influence the cellular resting membrane potential. Voltage-gated channels on the other sideopen and close rapidly creating rapid signals called action potentials. These action potentials are generated near cell body and are transmitted along the axon till the nerve terminal without much decrement due to myelination of axon. At the nerve terminal, the action potential-induced depolarization opens voltage-gated calcium channels, which release chemicals called neuro-transmitters outside the neuron. When the neurotransmitter binds to another neuron it alters its excitability and thereby transferring the information, which is further propagated till its intended end site.
Performance improvement of the osmotic microbial fuel cell by the pre-treatment of anaerobic sewage sludge using solenoid magnetic field
Published in Environmental Technology, 2023
Mandar S. Bhagat, Arvind Kumar Mungray, Alka A. Mungray
A cell membrane has four different kinds of ion channel, as shown in Figure 6: a voltage-gated channel, an intracellular ligand-gated channel, an extracellular ligand-gated channel, and a stress-activated channel. Binding ligands and mechanical stress (such as vibration, sound waves, temperature, UV radiation, a magnetic field, and so on) are important stimuli that cause ion channels to open. As a result of this activity, the cell membrane endocytosis and exocytosis processes are activated [34,35]. These processes in bacteria increase the removal efficiency of organic matter present in wastewater. On the other hand, the metabolic functions of bacteria may be adversely affected by continuous, high-intensity SOMF.