Nonlinear material and ionic transport through membrane nanotubes

Membrane nanotubes (NTs) and their networks play an important role in intracellular membrane transport and intercellular communications. The transport characteristics of the NT lumen resemble those of conventional solid-state nanopores. However, unlike the rigid pores, the soft membrane wall of the NT can be deformed by forces driving the transport through the NT lumen. This intrinsic coupling between the NT geometry and transport properties remains poorly explored. Using synchronized fluorescence microscopy and conductance measurements, we revealed that the NT shape was changed by both electric and hydrostatic forces driving the ionic and solute fluxes through the NT lumen. Far from the shape instability, the strength of the force effect is determined by the lateral membrane tension and is scaled with membrane elasticity so that the NT can be operated as a linear elastic sensor. Near shape instabilities, the transport forces triggered large-scale shape transformations, both stochastic and periodic. The periodic oscillations were coupled to a vesicle passage along the NT axis, resembling peristaltic transport. The oscillations were parametrically controlled by the electric field, making NT a highly nonlinear nanofluidic circuitry element with biological and technological implications.This work was partially supported by NIGMS of the National Institutes of Health under award R01GM121725, RYC-2014-01419 to A.V.S.; Spanish Ministry of Science, Innovation and Universities grants PGC2018-099971-B-I00 and EUR2019-103830 to A.V.S.; Basque Government grant IT1270-19; and the Ministry of Science and Higher Education of the Russian Federation to P.I.K. and G.T.R

РЕАБИЛИТАЦИЯ БОЛЬНЫХ ПОСЛЕ РАДИКАЛЬНОЙ ПРОСТАТЭКТОМИИ

According to the data obtained by Russian and foreign investigators, the major complication after radical prostatectomy (RPE) is urinaryincontinence that is recorded in 20-30% of cases.Objective. To improve the results of surgical treatment in patients with prostate cancer, by developing and introducing a well-rounded post-operative rehabilitation program.Subjects and methods. Seventy-four patients who were treated at the urology clinic, Bashkir State Medical University, and underwent RPEin 2005 to 2007 have been examined; 27 of them were diagnosed as having urinary incontinence (UI). After discharge from the clinic, acontrol group received rehabilitative treatment at the sanatorium “Krasnousolsk” of the Republic of Bashkortostan. Results and discussion. Therapeutic exercises and pelvic floor electrostimulation halve the number of day urinations and paddings used inpatients with UI, by increasing the bladder capacity from 138.2±12.7 to 196±11.2 ml and improving the trophism of the bladder neck andurethra in the sphincteral area. Реабилитация больных после радикальной простатэктоми

Изменения ультраструктуры и микроциркуляции стенки мочевого пузыря у пациентов с неинвазивными формами рака

Bladder cancer relapses are associated with diffuse pattern of neoplastic changes in the mucous layer of the bladder; treatment efficacy depends on the degree of structural alterations in the bladder wall.Materials and methods: for evaluation of microcirculation characteristics and structural alterations of mucous layer of the bladder we have used laser analyzer of capillary blood circulation («ЛАКК-01» produced by НПП «ЛАЗМА», Russia) and compact mobile optic tomograph (ИПФ РАН, Russia).Results: conducted researches have shown alterations affecting both epithelial and submucous layers with their microcirculatory bed in perifocal to bladder tumor tissues.Conclusions: complimentary application of laser Doppler flowmeter and compact mobile optic tomograph allows defining the type and extent of pathologic process in the bladder wall in superficial tumors and choosing optimal method of correction.

REHABILITATION OF PATIENTS AFTER RADICAL PROSTATECTOMY

According to the data obtained by Russian and foreign investigators, the major complication after radical prostatectomy (RPE) is urinaryincontinence that is recorded in 20-30% of cases.Objective. To improve the results of surgical treatment in patients with prostate cancer, by developing and introducing a well-rounded post-operative rehabilitation program.Subjects and methods. Seventy-four patients who were treated at the urology clinic, Bashkir State Medical University, and underwent RPEin 2005 to 2007 have been examined; 27 of them were diagnosed as having urinary incontinence (UI). After discharge from the clinic, acontrol group received rehabilitative treatment at the sanatorium “Krasnousolsk” of the Republic of Bashkortostan. Results and discussion. Therapeutic exercises and pelvic floor electrostimulation halve the number of day urinations and paddings used inpatients with UI, by increasing the bladder capacity from 138.2±12.7 to 196±11.2 ml and improving the trophism of the bladder neck andurethra in the sphincteral area. </p

Changes of the ultrastructure and microcirculation of bladder wall in patients with non-invasive types of cancer

Bladder cancer relapses are associated with diffuse pattern of neoplastic changes in the mucous layer of the bladder; treatment efficacy depends on the degree of structural alterations in the bladder wall.Materials and methods: for evaluation of microcirculation characteristics and structural alterations of mucous layer of the bladder we have used laser analyzer of capillary blood circulation («ЛАКК-01» produced by НПП «ЛАЗМА», Russia) and compact mobile optic tomograph (ИПФ РАН, Russia).Results: conducted researches have shown alterations affecting both epithelial and submucous layers with their microcirculatory bed in perifocal to bladder tumor tissues.Conclusions: complimentary application of laser Doppler flowmeter and compact mobile optic tomograph allows defining the type and extent of pathologic process in the bladder wall in superficial tumors and choosing optimal method of correction

Line Activity of Ganglioside GM1 Regulates the Raft Size Distribution in a Cholesterol-Dependent Manner

Liquid-ordered lipid domains, also called rafts, are assumed to be important players in different cellular processes, mainly signal transduction and membrane trafficking. They are thicker than the disordered part of the membrane and are thought to form to compensate for the hydrophobic mismatch between transmembrane proteins and the lipid environment. Despite the existence of such structures in vivo still being an open question, they are observed in model systems of multicomponent lipid bilayers. Moreover, the predictions obtained from model experiments allow the explanation of different physiological processes possibly involving rafts. Here we present the results of the study of the regulation of raft size distribution by ganglioside GM1. Combining atomic force microscopy with theoretical considerations based on the theory of membrane elasticity, we predict that this glycolipid should change the line tension of raft boundaries in two different ways, mainly depending on the cholesterol content. These results explain the shedding of gangliosides from the surface of tumor cells and the following ganglioside-induced apoptosis of T-lymphocytes in a raft-dependent manner. Moreover, the generality of the model allows the prediction of the line activity of different membrane components based on their molecular geometry