Biology subjects

Shneider, M.

Publications and source records attributed to Shneider, M..

4 recordsLinked to original sources

bioRxiv2023

The effect of intercellular medium salinity on the dielectric constant of cell membranes and the excitation thresholds of the action potential

A mechanism for axon swelling and subsequent compression in the area of action potential passage is considered. It is shown that the dynamics of changes in the radius of the axon during the passage of the action potential can be explained by changes in osmotic pressure. Axon swelling occurs at the leading edge of the action potential when Na+ ions flow from the extracellular electrolyte into the intracellular space, and subsequent compression occurs at the trailing edge during the ejection of K+ ions. The change in dielectric constant of the axon membrane is also discussed, and a possible explanation for the decrease in the excitation threshold of the action potential with an increase in salinity of the external electrolyte is proposed.

biophysics↗

bioRxiv2022

The possibility of anesthesia stimulated by a train of current pulses

This paper considers a simple theoretical model of blocking the passage of signals (action potentials) from sensory neurons and thereby effecting anesthesia without the use of anesthetics as a result of a sequence of unipolar current pulses generated by an external source. The proposed model allows the selection of parameters and the required frequency of the repetition of current pulses for the possible implementation of anesthesia depending on the electrical characteristics of the skin and the conductivity of the saline solution in which the myelinated nerve fibers are located.

bioengineering↗

bioRxiv2021

Physical model of electrical synapses in a neural network

A theoretical model of electrical synapses is proposed, in which connexons play the role of "nails" that hold unmyelinated areas of neurons at a distance of about 3.5 nm, and the electrical connection between them is provided by charging the membrane of an inactive neuron with currents generated in the intercellular electrolyte (saline) by the action potential in the active neuron. This mechanism is similar to the salutatory conduction of the action potential between the nodes of Ranvier in myelinated axons and the ephaptic coupling of sufficiently close spaced neurons.

biophysics↗

bioRxiv2019

Crystal Structure of the putative tail fiber protein gp53 from the Acinetobacter baumannii bacteriophage AP22

This report describes the structure of a putative tail fiber protein of the Acinetobacter baumannii bacteriophage AP22. The target host range of strictly lytic bacteriophage AP22 includes many clinical isolates of A. baumannii from hospitals in Chelyabinsk, Nizhny Novgorod, Moscow and St. Petersburg (Russia), but its host cell binding apparatus remains uncharacterized. Here, we report the crystal structure of the C-terminal fragment of AP22 gene product 53 (gp53) one of its two putative host cell-binding proteins. We show that gp53 forms a trimeric fiber and binds ethylene glycol and glycerol molecules that represent known surrogates of the oligosaccharide backbone. However, despite its structural similarities to other phage/virus host cell-binding fibers and its binding to small sugar-like molecules, gp53 did not inhibit AP22 infection and its role in the infection process remains unclear.

biophysics↗