Journal articles: 'Sodium Ion Cells'

1

Ban, Yue, Benjamin E. Smith, and Michael R. Markham. "A highly polarized excitable cell separates sodium channels from sodium-activated potassium channels by more than a millimeter." Journal of Neurophysiology 114, no. 1 (July 2015): 520–30. http://dx.doi.org/10.1152/jn.00475.2014.

Full text

Abstract:

The bioelectrical properties and resulting metabolic demands of electrogenic cells are determined by their morphology and the subcellular localization of ion channels. The electric organ cells (electrocytes) of the electric fish Eigenmannia virescens generate action potentials (APs) with Na+ currents >10 μA and repolarize the AP with Na+-activated K+ (KNa) channels. To better understand the role of morphology and ion channel localization in determining the metabolic cost of electrocyte APs, we used two-photon three-dimensional imaging to determine the fine cellular morphology and immunohistochemistry to localize the electrocytes' ion channels, ionotropic receptors, and Na+-K+-ATPases. We found that electrocytes are highly polarized cells ∼1.5 mm in anterior-posterior length and ∼0.6 mm in diameter, containing ∼30,000 nuclei along the cell periphery. The cell's innervated posterior region is deeply invaginated and vascularized with complex ultrastructural features, whereas the anterior region is relatively smooth. Cholinergic receptors and Na+ channels are restricted to the innervated posterior region, whereas inward rectifier K+ channels and the KNa channels that terminate the electrocyte AP are localized to the anterior region, separated by >1 mm from the only sources of Na+ influx. In other systems, submicrometer spatial coupling of Na+ and KNa channels is necessary for KNa channel activation. However, our computational simulations showed that KNa channels at a great distance from Na+ influx can still terminate the AP, suggesting that KNa channels can be activated by distant sources of Na+ influx and overturning a long-standing assumption that AP-generating ion channels are restricted to the electrocyte's posterior face.

APA, Harvard, Vancouver, ISO, and other styles

2

Li, Xianji, Andrew L. Hector, John R. Owen, and S. Imran U. Shah. "Evaluation of nanocrystalline Sn3N4derived from ammonolysis of Sn(NEt2)4as a negative electrode material for Li-ion and Na-ion batteries." Journal of Materials Chemistry A 4, no. 14 (2016): 5081–87. http://dx.doi.org/10.1039/c5ta08287k.

Full text

Abstract:

Bulk nanocrystalline Sn₃N₄powders were synthesised by a two step ammonolysis route. These provided good capacities in sodium and lithium cells, and good stability in sodium cells.

APA, Harvard, Vancouver, ISO, and other styles

3

Sabzpoushan, S. H., and A. Faghani Ghodrat. "Role of Sodium Channel on Cardiac Action Potential." Engineering, Technology & Applied Science Research 2, no. 3 (June 4, 2012): 232–36. http://dx.doi.org/10.48084/etasr.174.

Full text

Abstract:

Sudden cardiac death is a major cause of death worldwide. In most cases, it's caused by abnormal action potential propagation that leads to cardiac arrhythmia. The aim of this article is to study the abnormal action potential propagation through sodium ion concentration variations. We use a new electrophysiological model that is both detailed and computationally efficient. This efficient model is based on the partial differential equation method. The central finite difference method is used for numerical solving of the two-dimensional (2D) wave propagation equation. Simulations are implemented in two stages, as a single cardiac cell and as a two-dimensional grid of cells. In both stages, the normal action potential formation in case of a single cell and it's normal propagation in case of a two-dimensional grid of cells were simulated with nominal sodium ion conductance. Then, the effect of sodium ion concentration on the action potential signal was studied by reducing the sodium ion conductance. It is concluded that reducing the sodium ion conductance, decreases both passing ability and conduction velocity of the action potential wave front.

APA, Harvard, Vancouver, ISO, and other styles

4

Niu, Yu‐Bin, Ya‐Xia Yin, and Yu‐Guo Guo. "Nonaqueous Sodium‐Ion Full Cells: Status, Strategies, and Prospects." Small 15, no. 32 (March 25, 2019): 1900233. http://dx.doi.org/10.1002/smll.201900233.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Stanton, B. A., and B. Kaissling. "Regulation of renal ion transport and cell growth by sodium." American Journal of Physiology-Renal Physiology 257, no. 1 (July 1, 1989): F1—F10. http://dx.doi.org/10.1152/ajprenal.1989.257.1.f1.

Full text

Abstract:

Intracellular sodium has been implicated in a variety of cellular processes including regulation of Na+-K+-ATPase activity, mitogen-induced cell growth, and proliferation and stimulation of Na+-K+-ATPase by aldosterone. In renal epithelial cells a rise in sodium uptake across the apical membrane increases intracellular sodium concentration, which in turn stimulates the turnover rate of Na+-K+-ATPase and thereby enhances sodium efflux across the basolateral membrane. A prolonged increase in sodium uptake causes dramatic hypertrophy and hyperplasia and a rise in the quantity of Na+-K+-ATPase in the basolateral membrane. These structural and functional changes occur in the kidney in the absence of alterations in plasma aldosterone and vasopressin levels. Several mitogens induce growth and proliferation by initiating a cascade of events, which include a rise in intracellular sodium. Accordingly, an increase in the sodium concentration within renal epithelial cells may elicit a “mitogen-like” effect by initiating the cascade at the sodium step, even in the absence of a mitogen. A rise in cell sodium may also stimulate the production of autocrine growth factors that directly or indirectly regulate cell growth and proliferation, by modifying the response to mitogens or to changes in the ionic composition of the extracellular fluid. In this review we will examine the evidence that supports a role for intracellular sodium in regulating these cellular events in renal epithelial cells.

APA, Harvard, Vancouver, ISO, and other styles

6

Karasawa, Akira, Haijiao Liu, Matthias Quick, Wayne A. Hendrickson, and Qun Liu. "Crystallographic Characterization of Sodium Ions in a Bacterial Leucine/Sodium Symporter." Crystals 13, no. 2 (January 20, 2023): 183. http://dx.doi.org/10.3390/cryst13020183.

Full text

Abstract:

Na+ is the most abundant ion in living organisms and plays essential roles in regulating nutrient uptake, muscle contraction, and neurotransmission. The identification of Na+ in protein structures is crucial for gaining a deeper understanding of protein function in a physiological context. LeuT, a bacterial homolog of the neurotransmitter:sodium symporter family, uses the Na+ gradient to power the uptake of amino acids into cells and has been used as a paradigm for the study of Na+-dependent transport systems. We have devised a low-energy multi-crystal approach for characterizing low-Z (Z ≤ 20) anomalous scattering ions such as Na+, Mg2+, K+, and Ca2+ by combining Bijvoet-difference Fourier syntheses for ion detection and f” refinements for ion speciation. Using the approach, we experimentally identify two Na+ bound near the central leucine binding site in LeuT. Using LeuT microcrystals, we also demonstrate that Na+ may be depleted to study conformational changes in the LeuT transport cycle.

APA, Harvard, Vancouver, ISO, and other styles

7

Berkowitz, L. R., and E. P. Orringer. "Passive sodium and potassium movements in sickle erythrocytes." American Journal of Physiology-Cell Physiology 249, no. 3 (September 1, 1985): C208—C214. http://dx.doi.org/10.1152/ajpcell.1985.249.3.c208.

Full text

Abstract:

Deoxygenation causes an increase in passive Na and K movements across the membrane of the sickle erythrocyte. Some investigators find that these ion movements are accompanied by cell dehydration, while others find no evidence for cell water loss with sickling. Because gelation of hemoglobin S would be enhanced by cell water loss, we reinvestigated Na and K movements in sickle cells to define further the role that ion movements might play in the pathogenesis of sickling. With deoxygenation, we found that sickle cells gained Na and lost K without losing cell water. These net ion movements were not seen in control red blood cells. For sickle cells, deoxygenation also increased passive unidirectional influxes of Na and K, effects not observed when control red blood cells were deoxygenated. The deoxygenation-induced passive influxes of Na and K in sickle cells were not diminished by anion substitution or by the addition of the diuretic furosemide. We also found differences in passive Na and K fluxes between oxygenated sickle cells and normal red blood cells. The addition of furosemide or replacement of Cl with NO3 or SCN, maneuvers that largely reduced passive Na and K movements in oxygenated normal cells, had no effect on Na and K movements in oxygenated sickle cells. These findings militate against the idea that solute and water loss occur as a consequence of deoxygenation but do indicate that there are acquired membrane abnormalities in sickle red blood cells.

APA, Harvard, Vancouver, ISO, and other styles

8

Peters, Jens, Alexandra Peña Cruz, and Marcel Weil. "Exploring the Economic Potential of Sodium-Ion Batteries." Batteries 5, no. 1 (January 16, 2019): 10. http://dx.doi.org/10.3390/batteries5010010.

Full text

Abstract:

Sodium-ion batteries (SIBs) are a recent development being promoted repeatedly as an economically promising alternative to lithium-ion batteries (LIBs). However, only one detailed study about material costs has yet been published for this battery type. This paper presents the first detailed economic assessment of 18,650-type SIB cells with a layered oxide cathode and a hard carbon anode, based on existing datasheets for pre-commercial battery cells. The results are compared with those of competing LIB cells, that is, with lithium-nickel-manganese-cobalt-oxide cathodes (NMC) and with lithium-iron-phosphate cathodes (LFP). A sensitivity analysis further evaluates the influence of varying raw material prices on the results. For the SIB, a cell price of 223 €/kWh is obtained, compared to 229 €/kWh for the LFP and 168 €/kWh for the NMC batteries. The main contributor to the price of the SIB cells are the material costs, above all the cathode and anode active materials. For this reason, the amount of cathode active material (e.g., coating thickness) in addition to potential fluctuations in the raw material prices have a considerable effect on the price per kWh of storage capacity. Regarding the anode, the precursor material costs have a significant influence on the hard carbon cost, and thus on the final price of the SIB cell. Organic wastes and fossil coke precursor materials have the potential of yielding hard carbon at very competitive costs. In addition, cost reductions in comparison with LIBs are achieved for the current collectors, since SIBs also allow the use of aluminum instead of copper on the anode side. For the electrolyte, the substitution of lithium with sodium leads to only a marginal cost decrease from 16.1 to 15.8 €/L, hardly noticeable in the final cell price. On the other hand, the achievable energy density is fundamental. While it seems difficult to achieve the same price per kWh as high energy density NMC LIBs, the SIB could be a promising substitute for LFP cells in stationary applications, if it also becomes competitive with LFP cells in terms of safety and cycle life.

APA, Harvard, Vancouver, ISO, and other styles

9

Cragg, Peter J. "Artificial Transmembrane Channels for Sodium and Potassium." Science Progress 85, no. 3 (August 2002): 219–41. http://dx.doi.org/10.3184/003685002783238780.

Full text

Abstract:

Transport of alkali metals, particularly sodium and potassium, across cell membranes is an essential function performed by special proteins that enable cells to regulate inter- and extracellular ion concentrations with exceptional selectivity. The importance of these channel-forming proteins has led to researchers emulating of their structural features: an ion-specific filter and conduction at rates up to 108 ions per second. Synthetic helical and cyclic polypeptides form channels, however, the specificity of ion transport is often low. Ion-specific macrocycles have been used as filters from which membrane-spanning derivatives have been prepared. Success has been limited as many compounds act as ion carriers rather than forming transmembrane channels. Surfactant compounds also allow ions to cross membranes but any specificity is serendipitous. Overall it seems possible to mimic either ion specificity or efficient transmembrane ion transport. The goal for the future will be to combine both characteristics in one artificial system.

APA, Harvard, Vancouver, ISO, and other styles

10

Van Mil, H. G. J. "Analysis of a Model Describing the Dynamics of Intracellular Ion Composition in Biological Cells." International Journal of Bifurcation and Chaos 08, no. 05 (May 1998): 1043–47. http://dx.doi.org/10.1142/s0218127498000851.

Full text

Abstract:

An electrophysiological model describing the dynamics of the intracellular ion concentration and the membrane potential (Vm) in biological cells is presented. The model links passive ion fluxes through channels of sodium, potassium and chloride to active ion fluxes generated by the sodium potassium pump. To model the interaction of Vm to the ionic fluxes Kirchhoff current law is used. Only one Vm-dependent permeability as represented by an inwardly rectifying potassium channel (IKR) is incorporated. It is shown that the resulting system of ordinary differential equations is degenerate. Decomposition of the system into noninteracting subsystems allows a dynamically independent description of the currents of sodium and potassium in relation to Vm. Physical and mathematical arguments for the decomposition into subsystems are presented. Analysis of the model show hysteresis properties that can account for the experimentally-observed bistability in skeletal and heart muscles fibers.

APA, Harvard, Vancouver, ISO, and other styles

11

Zhu, Kai, Shaohua Guo, Jin Yi, Songyan Bai, Yingjin Wei, Gang Chen, and Haoshen Zhou. "A new layered sodium molybdenum oxide anode for full intercalation-type sodium-ion batteries." Journal of Materials Chemistry A 3, no. 44 (2015): 22012–16. http://dx.doi.org/10.1039/c5ta05444c.

Full text

Abstract:

A new layered Na_0.3MoO₂ exhibits a reversible capacity of 146 mA h g⁻¹, remarkable cycling stability and good rate capability for sodium half-cells. And a Na_0.3MoO₂//Na_0.8Ni_0.4Ti_0.6O₂ full intercalation-type sodium-ion cell is fabricated and it displays an excellent cycling stability. These results indicate that molybdenum-based oxide is a promising anode material for sodium-ion batteries.

APA, Harvard, Vancouver, ISO, and other styles

12

Nikinmaa, Mikko, and Bruce L. Tufts. "Regulation of acid and ion transfer across the membrane of nucleated erythrocytes." Canadian Journal of Zoology 67, no. 12 (December 1, 1989): 3039–45. http://dx.doi.org/10.1139/z89-427.

Full text

Abstract:

The major pathways for proton transport across the membrane of nucleated erythrocytes are the passive Jacobs–Stewart cycle and the secondarily active sodium–proton exchange. The relative importance of these two pathways in the control of red cell pH depends on the sodium–proton exchange rate and the rate of the slowest step of passive proton equilibration. In cyclostome red cells, which lack anion exchange, intracellular pH is controlled by the sodium-dependent acid–extrusion mechanism. In unstimulated teleost red cells, the Jacobs–Stewart cycle appears to be the most important pathway for the transport of protons across the membrane. Adrenergic stimulation activates sodium–proton exchange. Sodium–proton exchange is able to increase intracellular pH and decrease extracellular pH because the rate of proton transport via the Jacobs–Stewart cycle is limited by the uncatalysed extracellular dehydration of carbonic acid to carbon dioxide. The turnover rate of the adrenergically activated sodium–proton exchange is influenced by pH and oxygen tension. In amphibian red cells, acidification activates sodium–proton exchange. The exchange may limit the changes in intracellular pH after acid–base disturbances.

APA, Harvard, Vancouver, ISO, and other styles

13

Hambleton, T. A., J. R. Bourke, G. J. Huxham, and S. W. Manley. "Sodium dependence of the thyrotrophin-induced depolarization in cultured porcine thyroid cells." Journal of Endocrinology 108, no. 2 (February 1986): 225–30. http://dx.doi.org/10.1677/joe.0.1080225.

Full text

Abstract:

ABSTRACT Cultured porcine thyroid cells exhibit a resting membrane potential of about − 73 mV and depolarize to about − 54 mV on exposure to TSH. The depolarizing response to TSH was preserved in a medium consisting only of inorganic salts and buffers, but was abolished in sodium-free medium, demonstrating dependence on an inward sodium current. Increasing the potassium concentration of the medium resulted in a reduction in the resting membrane potential of 60 mV per tenfold change in potassium concentration, and a diminished TSH response. A hyperpolarizing TSH response was observed in a sodium- and bicarbonate-free medium, indicating that a hyperpolarizing ion current (probably carried by potassium) was also enhanced in the presence of TSH. Tetrodotoxin blocked the TSH response. We conclude that the response of the thyroid cell membrane to TSH involves increases in permeability to sodium and potassium, and that the thyroid membrane ion channels bear some similarity to the voltage-dependent sodium channels of excitable tissues, despite the absence of action potentials in the thyroid. J. Endocr. (1986) 108, 225–230

APA, Harvard, Vancouver, ISO, and other styles

14

Rudola, Ashish, Christopher J. Wright, and Jerry Barker. "Reviewing the Safe Shipping of Lithium-Ion and Sodium-Ion Cells: A Materials Chemistry Perspective." Energy Material Advances 2021 (November 25, 2021): 1–12. http://dx.doi.org/10.34133/2021/9798460.

Full text

Abstract:

High energy density lithium-ion (Li-ion) batteries are commonly used nowadays. Three decades’ worth of intense research has led to a good understanding on several aspects of such batteries. But, the issue of their safe storage and transportation is still not widely understood from a materials chemistry perspective. Current international regulations require Li-ion cells to be shipped at 30% SOC (State of Charge) or lower. In this article, the reasons behind this requirement for shipping Li-ion batteries are firstly reviewed and then compared with those of the analogous and recently commercialized sodium-ion (Na-ion) batteries. For such alkali-ion batteries, the safest state from their active materials viewpoint is at 0 V or zero energy, and this should be their ideal state for storage/shipping. However, a “fully discharged” Li-ion cell used most commonly, composed of graphite-based anode on copper current collector, is not actually at 0 V at its rated 0% SOC, contrary to what one might expect—the detailed mechanism behind the reason for this, namely, copper dissolution, and how it negatively affects cycling performance and cell safety, will be summarized herein. It will be shown that Na-ion cells, capable of using a lighter and cheaper aluminum current collector on the anode, can actually be safely discharged to 0 V (true 0% SOC) and beyond, even to reverse polarity (negative voltages). It is anticipated that this article spurs further research on the 0 V capability of Na-ion systems, with some suggestions for future studies provided.

APA, Harvard, Vancouver, ISO, and other styles

15

Negulyaev, Yu A., and E. A. Vedernikova. "Hydrogen ion block of single sodium channels in neuroblastoma cells." Neurophysiology 21, no. 1 (1989): 87–90. http://dx.doi.org/10.1007/bf01059108.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Ren, Wenhao, Zixuan Zhu, Qinyou An, and Liqiang Mai. "Emerging Prototype Sodium-Ion Full Cells with Nanostructured Electrode Materials." Small 13, no. 23 (April 10, 2017): 1604181. http://dx.doi.org/10.1002/smll.201604181.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Kulkarni, Nalini H., Rosamund C. Smith, and Bonnie L. Blazer-Yost. "Loss of inversin decreases transepithelial sodium transport in murine renal cells." American Journal of Physiology-Cell Physiology 313, no. 6 (December 1, 2017): C664—C673. http://dx.doi.org/10.1152/ajpcell.00359.2016.

Full text

Abstract:

Type II nephronophthisis (NPHP2) is an autosomal recessive renal cystic disorder characterized by mutations in the inversin gene. Humans and mice with mutations in inversin have enlarged cystic kidneys that may be due to fluid accumulation resulting from altered ion transport. To address this, transepithelial ion transport was measured in shRNA-mediated inversin-depleted mouse cortical collecting duct (mCCD) cells. Loss of inversin decreased the basal ion flux in mCCD cells compared with controls. Depletion of inversin decreased vasopressin-induced Na+ absorption but did not alter Cl− secretion by mCCD cells. Addition of amiloride, a specific blocker of the epithelial sodium channel (ENaC), abolished basal ion transport in both inversin knockdown and control cells, indicating ENaC involvement. Transcript levels of ENaC β-subunit were reduced in inversin-knockdown cells consistent with decreased ENaC activity. Furthermore, Nedd4l (neural precursor cell expressed, developmentally downregulated 4 like), an upstream negative regulator of ENaC, was evaluated. The relative amount of the phosphorylated, inactive Nedd4l was decreased in inversin-depleted cells consistent with decreased ENaC activity. The protein levels of Sgk1 (serum and glucocorticoid-inducible kinase), which phosphorylates Nedd4l, remained unchanged although the transcript levels were increased in inversin-depleted cells. Interestingly, mRNA and protein levels of Crtc2 (Creb-regulated transcription coactivator) kinase, a positive regulator of Sgk1, were decreased in inversin-depleted cells. Together these results suggest that loss of inversin decreases Na+ transport via ENaC, mediated in part by transcriptional and posttranslational regulation of Crtc2/Sgk1/Nedd4l axis as a contributory mechanism for enlarged kidneys in NPHP2.

APA, Harvard, Vancouver, ISO, and other styles

18

Lübcke, Ralf, and Gilbert O. Barbezat. "Intestinal ion transport in rats with spontaneous arterial hypertension." Clinical Science 75, no. 2 (August 1, 1988): 127–33. http://dx.doi.org/10.1042/cs0750127.

Full text

Abstract:

1. Ion balance, intestinal ion transport in vivo with luminal Ringer, and direct voltage clamping in vivo with luminal Ringer and sodium-free choline-Ringer were studied in young (40 days old) and adult (120 days old) spontaneously hypertensive rats (SHR) and age-matched normotensive controls (Wistar–Kyoto rats, WKY). 2. Faecal sodium output was significantly higher in SHR compared with WKY in both young (+ 67%) and adult (+ 43%) rats. 3. Small-intestinal sodium absorption was equal in young SHR and WKY, but significantly greater net sodium absorption was found in the ileum of adult SHR. In contrast, net sodium absorption was reduced from the colon of both young and adult SHR. 4. In adult SHR, the colonic transepithelial short-circuit current (Isc) and the transepithelial potential difference (PD) were significantly higher, whereas the transepithelial membrane resistance (Rm) was significantly lower than in WKY. There was an identical drop in Isc in both strains when luminal sodium was replaced by choline. These data cannot be explained by increased electrogenic cation (sodium) absorption in the SHR, but would favour chloride secretion. 5. It is suggested that in SHR membrane electrolyte transport abnormalities may also be present in the epithelial cells of the small and large intestine, as have been demonstrated already in blood cells by several investigators. The SHR may become an interesting experimental animal model for the study of generalized ion transport disorders.

APA, Harvard, Vancouver, ISO, and other styles

19

Willow, Ashley, Haytham E. M. Hussein, and Serena Margadonna. "Anode-Free Sodium Ion Batteries: Effect of Pressure on Sodium Plating on Copper." ECS Meeting Abstracts MA2022-01, no. 1 (July 7, 2022): 103. http://dx.doi.org/10.1149/ma2022-011103mtgabs.

Full text

Abstract:

Sodium ion anode-free battery technology puts extra emphasis on high plating and stripping efficiency of sodium metal at the anode surface, due to the lack of an excess of the transporting ion. Recent studies have shown the importance of strict control of water content in enabling efficient plating and stripping of sodium on copper in the 1M NaPF6 in diglyme electrolyte[1]. We have achieved promising results at coin cell level in this configuration: 99.9% coulombic efficiency over 400 cycles, low nucleation overpotential of 40mV and 10mV hysteresis at 0.2mA cm-2, without dendrite formation. To demonstrate the scalability of the anode-free concept, we attempted plating and stripping of sodium metal on copper foils with areas that are 10-fold higher (>10 cm2) than those previously achievable in coin cells (~1cm2) using a split pouch cell configuration. Furthermore, we investigate the effect of pressure at this scale by using two methods. The initial method involves increasing spacer thickness, which acts to compress a wave spring within the split pouch cell. These experiments demonstrate that the plating and stripping voltage hysteresis can be decreased from 125mV -> 40mV -> 10mV, with increasing spacer thickness on the order 3mm -> 3.5mm -> 4mm. The hysteresis observed in coin cells is then matched when 4mm of spacers is used in split pouch cells, indicating a similar pressure applied in these two cell formats. Voltage instabilities are also reduced by increasing the spacer thickness, indicating the formation an increasingly stable solid electrolyte interface (SEI). Secondly, the optimal pressure for the Na||Cu half-cell is investigated by using a pressure calibration unit to accurately measure the applied force within a compressive jig. References: [1] Chengtian Zhou et al 2021 J. Electrochem. Soc. 168 060532 Figure 1

APA, Harvard, Vancouver, ISO, and other styles

20

Melyanovskaya, Yu L., E. I. Kondratyeva, and A. M. Budaeva. "Function of ion channels of epithelial cells in cystic fibrosis." PULMONOLOGIYA 33, no. 2 (April 12, 2023): 182–88. http://dx.doi.org/10.18093/0869-0189-2023-33-2-182-188.

Full text

Abstract:

Cystic fibrosis is a systemic hereditary disease caused by mutations in the CFTR gene, which regulates the transport of electrolytes (mainly chloride) across the membranes of the epithelial cells that line excretory ducts of exocrine glands. Dysfunction of the CFTR protein reduces passage of chloride ions through cell membranes and disrupts the passage of sodium ions, bicarbonate ions, and water.The aim of the study was to analyze comprehensively functioning of chloride and alternative (sodium and calcium) channels in the epithelium of patients with cystic fibrosis in relation to the age using functional tests in vitro.Methods. We used data from medical histories of patients with cystic fibrosis and intestinal current measurements.Results. The function of the calcium channel decreased with age in people without cystic fibrosis and carriers of “severe” genotypes. The function of sodium, chloride, and calcium channels was lower in all age groups of patients with cystic fibrosis compared to controls (p < 0.05). When comparing groups of patients with “severe genotype” and “mild genotype”, statistically significant differences were found in response to forskolin (p < 0.05). Patients with “mild” genotypes had a residual function of the CFTR channel which decreased with age.Conclusion. For the first time, the functioning of chloride and alternative channels in cystic fibrosis have been described in relation to the age and the genotype of patients.

APA, Harvard, Vancouver, ISO, and other styles

21

Russell, John M. "Sodium-Potassium-Chloride Cotransport." Physiological Reviews 80, no. 1 (January 1, 2000): 211–76. http://dx.doi.org/10.1152/physrev.2000.80.1.211.

Full text

Abstract:

Obligatory, coupled cotransport of Na+, K+, and Cl− by cell membranes has been reported in nearly every animal cell type. This review examines the current status of our knowledge about this ion transport mechanism. Two isoforms of the Na+-K+-Cl− cotransporter (NKCC) protein (∼120–130 kDa, unglycosylated) are currently known. One isoform (NKCC2) has at least three alternatively spliced variants and is found exclusively in the kidney. The other (NKCC1) is found in nearly all cell types. The NKCC maintains intracellular Cl− concentration ([Cl−]i) at levels above the predicted electrochemical equilibrium. The high [Cl−]i is used by epithelial tissues to promote net salt transport and by neural cells to set synaptic potentials; its function in other cells is unknown. There is substantial evidence in some cells that the NKCC functions to offset osmotically induced cell shrinkage by mediating the net influx of osmotically active ions. Whether it serves to maintain cell volume under euvolemic conditons is less clear. The NKCC may play an important role in the cell cycle. Evidence that each cotransport cycle of the NKCC is electrically silent is discussed along with evidence for the electrically neutral stoichiometries of 1 Na+:1 K+:2 Cl− (for most cells) and 2 Na+:1 K+:3 Cl− (in squid axon). Evidence that the absolute dependence on ATP of the NKCC is the result of regulatory phosphorylation/dephosphorylation mechanisms is decribed. Interestingly, the presumed protein kinase(s) responsible has not been identified. An unusual form of NKCC regulation is by [Cl−]i. [Cl−]i in the physiological range and above strongly inhibits the NKCC. This effect may be mediated by a decrease of protein phosphorylation. Although the NKCC has been studied for ∼20 years, we are only beginning to frame the broad outlines of the structure, function, and regulation of this ubiquitous ion transport mechanism.

APA, Harvard, Vancouver, ISO, and other styles

22

Villegas, R., Gloria M. Villegas, J. M. Rodriguez-Grille, and F. Sorais-Landaez. "The sodium channel of excitable and non-excitable cells." Quarterly Reviews of Biophysics 21, no. 1 (February 1988): 99–128. http://dx.doi.org/10.1017/s0033583500005035.

Full text

Abstract:

Excitation and conduction in the majority of excitable cells, as originally described in the squid axon, are initiated by a transient and highly selective increase of the membrane Na conductance, which allows this ion to move passively down its electrochemical gradient (Hodgkin & Katz, 1949; Hodgkin & Huxley, 1952). The term ‘Na channel’ was introduced to describe the mechanism involved in this conductance change (Hodgkin & Keynes, 1955).

APA, Harvard, Vancouver, ISO, and other styles

23

Wieland, S. J., J. E. Fletcher, H. Rosenberg, and Q. H. Gong. "Malignant hyperthermia: slow sodium current in cultured human muscle cells." American Journal of Physiology-Cell Physiology 257, no. 4 (October 1, 1989): C759—C765. http://dx.doi.org/10.1152/ajpcell.1989.257.4.c759.

Full text

Abstract:

Voltage-activated ion currents were measured in cultured skeletal muscle myoballs. Cultures were generated from biopsies from patients referred for diagnosis of susceptibility to malignant hyperthermia (MH); diagnosis of susceptibility (MH+) or nonsusceptibility (MH-) was made on the basis of in vitro halothane-induced contracture of a separate piece of biopsy. Measurements of ion currents were made at room temperature in the absence of anesthetic agents, using tight-seal whole-cell recording. Fast transient Na+ currents and delayed outward K+ currents were similar in magnitude and kinetics in cells from MH+ and MH- patients. An additional slowly inactivating inward current component was commonly observed in cells from MH+ patients. This current was blockable by tetrodotoxin and was carried by Na+ but not by Ba2+. The component was less frequently observed and was of a lower magnitude in cells from MH- patients. The increased magnitude of the slow inward current observed in cultured muscle cells from MH+ patients may be a manifestation of the lesion that causes MH.

APA, Harvard, Vancouver, ISO, and other styles

24

Peters, Jens F., Manuel Baumann, Joachim R. Binder, and Marcel Weil. "On the environmental competitiveness of sodium-ion batteries under a full life cycle perspective – a cell-chemistry specific modelling approach." Sustainable Energy & Fuels 5, no. 24 (2021): 6414–29. http://dx.doi.org/10.1039/d1se01292d.

Full text

Abstract:

Assessing different sodium-ion against current lithium-ion battery cells shows large difference between cell chemistries and a good environmental performance for manganese and Prussian blue-based cathodes under a full life cycle perspective.

APA, Harvard, Vancouver, ISO, and other styles

25

Lu, Bin, Chengjun Lin, Haiji Xiong, Chi Zhang, Lin Fang, Jiazhou Sun, Ziheng Hu, et al. "Hard-Carbon Negative Electrodes from Biomasses for Sodium-Ion Batteries." Molecules 28, no. 10 (May 11, 2023): 4027. http://dx.doi.org/10.3390/molecules28104027.

Full text

Abstract:

With the development of high-performance electrode materials, sodium-ion batteries have been extensively studied and could potentially be applied in various fields to replace the lithium-ion cells, owing to the low cost and natural abundance. As the key anode materials of sodium-ion batteries, hard carbons still face problems, such as poor cycling performance and low initial Coulombic efficiency. Owning to the low synthesis cost and the natural presence of heteroatoms of biomasses, biomasses have positive implications for synthesizing the hard carbons for sodium-ion batteries. This minireview mainly explains the research progress of biomasses used as the precursors to prepare the hard-carbon materials. The storage mechanism of hard carbons, comparisons of the structural properties of hard carbons prepared from different biomasses, and the influence of the preparation conditions on the electrochemical properties of hard carbons are introduced. In addition, the effect of doping atoms is also summarized to provide an in-depth understanding and guidance for the design of high-performance hard carbons for sodium-ion batteries.

APA, Harvard, Vancouver, ISO, and other styles

26

Lakienko, Grigorii P., Zoya V. Bobyleva, Maria O. Apostolova, Yana V. Sultanova, Andrey K. Dyakonov, Maxim V. Zakharkin, Nikita A. Sobolev, et al. "Sosnowskyi Hogweed-Based Hard Carbons for Sodium-Ion Batteries." Batteries 8, no. 10 (September 20, 2022): 131. http://dx.doi.org/10.3390/batteries8100131.

Full text

Abstract:

Sodium-ion battery technology rapidly develops in the post-lithium-ion landscape. Among the variety of studied anode materials, hard carbons appear to be the realistic candidates because of their electrochemical performance and relative ease of production. This class of materials can be obtained from a variety of precursors, and the most ecologically important and interesting route is the synthesis from biomass. In the present work, for the first time, hard carbons were obtained from Heracleum sosnowskyi, a highly invasive plant, which is dangerous for humans and can cause skin burns but produces a large amount of green biomass in a short time. We proposed a simple synthesis method that includes the pretreatment stage and further carbonization at 1300 °C. The effect of the pretreatment of giant hogweed on the hard carbon electrochemical properties was studied. Obtained materials demonstrate >220 mAh g−1 of the discharge capacity, high values of the initial Coulombic efficiency reaching 87% and capacity retention of 95% after 100 charge-discharge cycles in sodium half-cells. Key parameters of the materials were examined by means of different analytical, spectroscopic and microscopic techniques. The possibility of using the giant hogweed-based hard carbons in real batteries is demonstrated with full sodium-ion cells with NASICON-type Na3V2(PO4)3 cathode material.

APA, Harvard, Vancouver, ISO, and other styles

27

Yang, Yan, Zhen-Zhen Pan, Ying-Ying Wang, Yuan-Chuan Ma, Chong Li, Yu-Jun Lu, and Xing-Long Wu. "Correction: Ionic-liquid-bifunctional wrapping of ultrafine SnO2 nanocrystals into N-doped graphene networks: high pseudocapacitive sodium storage and high-performance sodium-ion full cells." Nanoscale 11, no. 31 (2019): 14959–60. http://dx.doi.org/10.1039/c9nr90160d.

Full text

Abstract:

Correction for ‘Ionic-liquid-bifunctional wrapping of ultrafine SnO₂ nanocrystals into N-doped graphene networks: high pseudocapacitive sodium storage and high-performance sodium-ion full cells’ by Yan Yang et al., Nanoscale, 2019, DOI: 10.1039/c9nr02542a.

APA, Harvard, Vancouver, ISO, and other styles

28

Yan, Yang, Zhen-Zhen Pan, Ying-Ying Wang, Yuan-Chuan Ma, Chong Li, Yu-Jun Lu, and Xing-Long Wu. "Correction: Ionic-liquid-bifunctional wrapping of ultrafine SnO2 nanocrystals into N-doped graphene networks: high pseudocapacitive sodium storage and high-performance sodium-ion full cells." Nanoscale 11, no. 35 (2019): 16690. http://dx.doi.org/10.1039/c9nr90193k.

Full text

Abstract:

Correction for ‘Ionic-liquid-bifunctional wrapping of ultrafine SnO₂ nanocrystals into N-doped graphene networks: high pseudocapacitive sodium storage and high-performance sodium-ion full cells’ by Yan Yang et al., Nanoscale, 2019, 11, 14616–14624.

APA, Harvard, Vancouver, ISO, and other styles

29

Stanchovska, Silva, Mariya Kalapsazova, Sonya Harizanova, Violeta Koleva, and Radostina Stoyanova. "Design of Sodium Titanate Nanowires as Anodes for Dual Li,Na Ion Batteries." Batteries 9, no. 5 (May 13, 2023): 271. http://dx.doi.org/10.3390/batteries9050271.

Full text

Abstract:

The bottleneck in the implementation of hybrid lithium-sodium-ion batteries is the lack of anode materials with a desired rate capability. Herein, we provide an in-depth examination of the Li-storage performance of sodium titanate nanowires as negative electrodes in hybrid Li,Na-ion batteries. Titanate nanowires were prepared by a simple and reproducible hydrothermal method. At a low reaction pressure, the well-isolated nanowires are formed, while by increasing the reaction pressure from 2 to 30 bar, the isolated nanowires tend to bundle. In nanowires, the local coordinations of Na and Ti atoms deviate from those in Na2Ti3O7 and Na2Ti6O13 and slightly depend on the reaction pressure. During the annealing at 350 °C, both Na and Ti coordinations undergo further changes. The nanowires are highly defective, and they easily crystallize into Na2Ti6O13 and Na2Ti3O7 phases. The lithium storage properties are evaluated in lithium-ion cells vs. lithium metal anode and titanate electrodes fabricated with PVDF and carboxymethyl cellulose (CMC) binders. The Li-storage by nanowires proceeds by a hybrid capacitive-diffusive mechanism between 0.1 and 2.5 V, which enables to achieve a high specific capacity. Sodium titanates accommodate Li+ by formation of mixed lithium-sodium-phase Na2−xLixTi6O13, which is decomposed to the distinct lithium phases Li0.54Ti2.86O6 and Li0.5TiO2. Contrary to lithium, the sodium storage is accomplished mainly by the capacitive reactions, and thus the phase composition is preserved during cycling in sodium ion cells. The isolated nanowires outperform bundled nanowires with respect to rate capability.

APA, Harvard, Vancouver, ISO, and other styles

30

Rudola, Ashish, Christopher J. Wright, and Jerry Barker. "Communication—Surprisingly High Fast Charge Volumetric Capacities of Hard Carbon Electrodes in Sodium-Ion Batteries." Journal of The Electrochemical Society 168, no. 11 (November 1, 2021): 110534. http://dx.doi.org/10.1149/1945-7111/ac377a.

Full text

Abstract:

We show herein that electrode-level effects of commercially-available hard carbon (HC) material, as a function of the HC loading, can have two surprising positive outcomes in sodium-ion (Na-ion) pouch cells. First, a HC electrode’s plating-free volumetric capacity actually increases as its loading (and areal capacity) decreases, and secondly, the plating-free volumetric capacity at sub-30 min charging times for HC as Na-ion anode, can be better vs that of graphite anode in lithium-ion (Li-ion) cells at the electrode-level, and actually be significantly higher than the latter at sub-20 min and sub-15 min charging times, despite HC’s lower density than graphite.

APA, Harvard, Vancouver, ISO, and other styles

31

Altamura, Giovanni, Charles Roger, Louis Grenet, Joël Bleuse, Hélène Fournier, Simon Perraud, and Henri Mariette. "Influence of sodium-containing substrates on Kesterite CZTSSe thin films based solar cells." MRS Proceedings 1538 (2013): 103–6. http://dx.doi.org/10.1557/opl.2013.1000.

Full text

Abstract:

AbstractThis work deals with the influence of sodium on the properties of CZTSSe material and solar cells. For that purpose, two types of substrates are compared, one with low sodium content (borosilicate glass), the other one with higher sodium content (soda-lime glass). In each case the Na-content in the CZTSSe passing from the substrate through the Mo back contact is quantified by secondary ion mass spectroscopy analysis. Photoluminescence spectroscopy indicates that better quality material is achievable when increasing the Na-content in the CZTSSe. The material characterization results are compared to the photovoltaic properties. Index Terms — Cu2ZnSn(S1-xSex)4, CZTSSe, CZTS, CZTSe, Sodium, Kesterite, thin film, solar cell.

APA, Harvard, Vancouver, ISO, and other styles

32

Mu, Jian-Jia, Zhao-Meng Liu, Qing-Song Lai, Da Wang, Xuan-Wen Gao, Dong-Run Yang, Hong Chen, and Wen-Bin Luo. "An industrial pathway to emerging presodiation strategies for increasing the reversible ions in sodium-ion batteries and capacitors." Energy Materials 2, no. 6 (2022): 200043. http://dx.doi.org/10.20517/energymater.2022.57.

Full text

Abstract:

Sodium-ion batteries (SIBs) and capacitors (SICs) have been drawing considerable interest in recent years and are considered two of the most promising candidates for next-generation battery technologies in the energy storage industry. Therefore, it is essential to explore feasible strategies to increase the energy density and cycling lifespan of these technologies for their future commercialization. However, relatively low Coulombic efficiency severely limits the energy density of sodium-ion full cells, particularly in the initial cycle, which gradually decreases the number of recyclable ions. Presodiation techniques are regarded as effective approaches to counteract the irreversible capacity in the initial cycle and boost the energy density of SIBs and SICs. Their cyclic stability can also be enhanced by the slow release of supplemental sodium and high-content recyclable ions during cycling. In this review, a general understanding of the sodium-ion loss pathways and presodiation process towards full cells with high Coulombic efficiency is summarized. From the perspectives of safety, operability and efficiency, the merits and drawbacks of various presodiation techniques are evaluated. This review attempts to provide a fundamental understanding of presodiation principles and strategies to promote the industrial development of SIBs and SICs.

APA, Harvard, Vancouver, ISO, and other styles

33

Chandra, S., E. P. Kable, G. H. Morrison, and W. W. Webb. "Calcium sequestration in the Golgi apparatus of cultured mammalian cells revealed by laser scanning confocal microscopy and ion microscopy." Journal of Cell Science 100, no. 4 (December 1, 1991): 747–52. http://dx.doi.org/10.1242/jcs.100.4.747.

Full text

Abstract:

Co-localization of the elements calcium, potassium, sodium and magnesium with sequestering organelles has been achieved by application of two microscopy techniques on the same cell. Organelles were first localized by laser scanning confocal microscopy (LSCFM) using fluorescent organelle stains. The same cells were then analyzed for elemental distribution with ion microscopy. This approach has identified a perinuclear region of prominent total calcium concentration with the Golgi apparatus. Live cells were fluorescently stained with C6-NBD-ceramide for labeling the Golgi apparatus prior to cryogenic preparation and freeze-drying, and imaged with LSCFM for Golgi localization; identical cells were then analyzed with ion microscopy to image subcellular distributions of total calcium, potassium, sodium and magnesium. In three cell lines, LLC-PK1 porcine kidney epithelial cells, Swiss 3T3 mouse fibroblast cells and L5 rat myoblast cells, the Golgi regions contained significantly higher total calcium concentrations than any other region of the cell (as measured at the spatial resolution of ion microscopy of about 0.5 micron). Intracellular potassium, sodium and magnesium were homogeneously distributed throughout the cell and did not show this pattern. Measurements of depletion of calcium by exposure to calcium-free medium showed that the Golgi apparatus was substantially more resistant to calcium depletion than all other regions of these cells, but sequestered Ca2+ could be released from the Golgi by exposing the cells to calcium ionophore A23187. The Golgi apparatus appears to sequester about 5% of the total cell calcium in LLC-PK1 cells, about 2.5% in 3T3 cells and L5 cells.

APA, Harvard, Vancouver, ISO, and other styles

34

Ganster, Raymond W., Rhonda R. McCartney, and Martin C. Schmidt. "Identification of a Calcineurin-Independent Pathway Required for Sodium Ion Stress Response in Saccharomyces cerevisiae." Genetics 150, no. 1 (September 1, 1998): 31–42. http://dx.doi.org/10.1093/genetics/150.1.31.

Full text

Abstract:

Abstract The calcium-dependent protein phosphatase calcineurin plays an essential role in ion homeostasis in yeast. In this study, we identify a parallel ion stress response pathway that is independent of the calcineurin signaling pathway. Cells with null alleles in both STD1 and its homologue, MTH1, manifest numerous phenotypes observed in calcineurin mutants, including sodium, lithium, manganese, and hydroxyl ion sensitivity, as well as alpha factor toxicity. Furthermore, increased gene dosage of STD1 suppresses the ion stress phenotypes in calcineurin mutants and confers halotolerance in wild-type cells. However, Std1p functions in a calcineurin-independent ion stress response pathway, since a std1 mth1 mutant is FK506 sensitive under conditions of ion stress. Mutations in other genes known to regulate gene expression in response to changes in glucose concentration, including SNF3, RGT2, and SNF5, also affect cell growth under ion stress conditions. Gene expression studies indicate that the regulation of HAL1 and PMR2 expression is affected by STD1 gene dosage. Taken together, our data demonstrate that response to ion stress requires the participation of both calcineurin-dependent and -independent pathways.

APA, Harvard, Vancouver, ISO, and other styles

35

Yang, Jie, and Mingyu Liu. "Role of a complex of two proteins in alleviating sodium ion stress in an economic crop." PLOS ONE 15, no. 11 (November 20, 2020): e0242221. http://dx.doi.org/10.1371/journal.pone.0242221.

Full text

Abstract:

An economically valuable woody plant species tree bean (Cajanus cajan (L.) Millsp.) is predominantly cultivated in tropical and subtropical areas and is regarded as an important food legume (or pulse) crop that is facing serious sodium ion stress. NAM (N-acetyl-5-methoxytryptamine) has been implicated in abiotic and biotic stress tolerance in plants. However, the role of NAM in sodium ion stress tolerance has not been determined. In this study, the effect of NAM was investigated in the economically valuable woody plant species, challenged with stress at 40 mM sodium ion for 3 days. NAM-treated plants (200 μM) had significantly higher fresh weight, average root length, significantly reduced cell size, increased cell number, and increased cytoskeleton filaments in single cells. The expression pattern of one of 10 Tree bean Dynamic Balance Movement Related Protein (TbDMP), TbDMP was consistent with the sodium ion-stress alleviation by NAM. Using TbDMP as bait, Dynamic Balance Movement Related Kinase Protein (TbDBK) was determined to interact with TbDMP by screening the tree bean root cDNA library in yeast. Biochemical experiments showed that NAM enhanced the interaction between the two proteins which promoted resist sodium ion stress resistance. This study provides evidence of a pathway through which the skeleton participates in NAM signaling.

APA, Harvard, Vancouver, ISO, and other styles

36

Nicholls, David G. "Mitochondrial ion circuits." Essays in Biochemistry 47 (June 14, 2010): 25–35. http://dx.doi.org/10.1042/bse0470025.

Full text

Abstract:

Proton circuits across the inner mitochondrial membrane link the primary energy generators, namely the complexes of the electron transport chain, to multiple energy utilizing processes, including the ATP synthase, inherent proton leak pathways, metabolite transport and linked circuits of sodium and calcium. These mitochondrial circuits can be monitored in both isolated preparations and intact cells and, for the primary proton circuit techniques, exist to follow both the proton current and proton electrochemical potential components of the circuit in parallel experiments, providing a quantitative means of assessing mitochondrial function and, equally importantly, dysfunction.

APA, Harvard, Vancouver, ISO, and other styles

37

Ransom, C. B., H. Sontheimer, and D. Janigro. "Astrocytic inwardly rectifying potassium currents are dependent on external sodium ions." Journal of Neurophysiology 76, no. 1 (July 1, 1996): 626–30. http://dx.doi.org/10.1152/jn.1996.76.1.626.

Full text

Abstract:

1. Two subtypes of astrocytes that expressed distinctly different ion channel complements were identified in primary cultures from rat spinal cord and hippocampus using whole cell patch-clamp techniques. One population of cells expressed voltage-activated Na+ currents and displayed outwardly rectifying I-V relationships; the other group of cells had no detectable Na+ currents and pronounced inwardly rectifying I-V curves. 2. Astrocytes expressing Na+ currents were hyperpolarized (by approximately 7 mV) upon removal of external sodium, suggesting a resting Na+ conductance in these cells. In contrast, cells expressing primarily inwardly rectifying K+ currents, Kir, depolarized (by approximately 4-6 mV) in low-sodium solutions. 3. Removal of external Na+ ions increased the input resistance (189% of control) and reduced the whole cell current amplitude (60% of control at -120 mV) of cells with Kir. The reduction in current amplitude was dose-dependent and became apparent after a 10% reduction of [Na+]0 in 7/7 cells tested. At -120 mV, the effect was near maximal in response to a 50% reduction of [Na+]0. 4. The outward potassium currents of cells expressing Na(+)-currents were unaffected by removal of bath Na+. 5. We conclude that the conductance of glial inwardly rectifying K+ channels is dependent on external sodium ions via a mechanism that does not involve sodium ion permeation or blockade of these channels.

APA, Harvard, Vancouver, ISO, and other styles

38

Russo, R. M., R. L. Lubman, and E. D. Crandall. "Evidence for amiloride-sensitive sodium channels in alveolar epithelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 262, no. 4 (April 1, 1992): L405—L411. http://dx.doi.org/10.1152/ajplung.1992.262.4.l405.

Full text

Abstract:

To maintain alveolar air spaces relatively fluid free, the alveolar epithelium appears capable of vectorial transport of water and solutes. Active transepithelial transport of sodium by alveolar epithelial cell monolayers has previously been demonstrated, indicating that alveolar pneumocytes must possess ion transport mechanisms by which sodium can enter the cells apically for subsequent extrusion via Na(+)-K(+)-adenosinetriphosphatase activity at the basolateral surface. In this study, sodium entry mechanisms were investigated by directly measuring 22Na uptake into rat alveolar epithelial cells grown in primary culture. Cells exhibited increasing 22Na uptake with time over a 30-min interval. Total sodium uptake was compared in the presence and absence of several sodium transport inhibitors. Uptake was inhibited by the sodium channel blockers amiloride and benzamil but was not affected by two amiloride analogues (bromohexamethylene amiloride and dimethylamiloride) with diminished specificity for blocking sodium channels and enhanced specificity for inhibiting the Na(+)-H+ antiporter. Uptake was also unaffected by the chloride transport inhibitor bumetanide or by the absence of glucose. These data suggest that sodium uptake occurs primarily via sodium channel and that Na(+)-H+ antiport, Na(+)-K(+)-2Cl- cotransport, and Na(+)-glucose cotransport do not contribute significantly to sodium uptake under these experimental conditions. The presence of sodium channels in the alveolar epithelial cell membrane may provide the major entry mechanism by which sodium enters these cells for subsequent active extrusion, thereby effecting net salt and water reabsorption from the alveolar spaces.

APA, Harvard, Vancouver, ISO, and other styles

39

Reichenbach, Andreas, Andre Henke, Wolfgang Eberhardt, Winfried Reichelt, and Dietrich Dettmer. "K+ ion regulation in retina." Canadian Journal of Physiology and Pharmacology 70, S1 (May 15, 1992): S239—S247. http://dx.doi.org/10.1139/y92-267.

Full text

Abstract:

During onset and offset of illumination, considerable changes in extracellular K+ concentration ([K+]e) occur within particular retinal layers. There are two ways in which glial cells may control [K+]e: (1) by space-independent processes, for example, by K+ uptake due to the Na+–K+ ATPase, and (2) by space-dependent processes, that is, by spatial buffering currents flowing through K+ channels. Rabbit retinal Müller (glial) cells were studied for expression of mechanisms supporting both kinds of processes. This review demonstrates that rabbit Müller cells have Na–K pumps whose distribution and properties are highly adapted to meet the needs of efficient K+ clearance. Furthermore, spatial buffering currents through specialized K+ channels of Müller cells greatly accelerate retinal K+ clearance during and after stimulation.Key words: glia, retina, potassium clearance, sodium–potassium pump, potassium channels.

APA, Harvard, Vancouver, ISO, and other styles

40

Ni, Qiao, Yuejiao Yang, Haoshen Du, Hao Deng, Jianbo Lin, Liu Lin, Mengwei Yuan, Zemin Sun, and Genban Sun. "Anode-Free Rechargeable Sodium-Metal Batteries." Batteries 8, no. 12 (December 5, 2022): 272. http://dx.doi.org/10.3390/batteries8120272.

Full text

Abstract:

Due to the advantages of rich resources, low cost, high energy conversion efficiency, long cycle life, and low maintenance fee, sodium–ion batteries have been regarded as a promising energy storage technology. However, their relatively low energy density compared with the commercialized lithium–ion batteries still impedes their application for power systems. Anode–free rechargeable sodium–metal batteries (AFSMBs) pose a solution to boost energy density and tackle the safety problems of metal batteries. At present, researchers still lack a comprehensive understanding of the anode-free cells in terms of electrolytes, solid–electrolyte interphase (SEI), and current collectors. This review is devoted to the field of AFSMBs, and outlines the breakthroughs that have been accomplished along with our perspective on the direction of future development for AFSMBs and the areas that warrant further investigation.

APA, Harvard, Vancouver, ISO, and other styles

41

Burnett, Paul, Janet K. Robertson, Jeffrey M. Palmer, Richard R. Ryan, Adrienne E. Dubin, and Robert A. Zivin. "Fluorescence Imaging of Electrically Stimulated Cells." Journal of Biomolecular Screening 8, no. 6 (December 2003): 660–67. http://dx.doi.org/10.1177/1087057103258546.

Full text

Abstract:

Designing high-throughput screens for voltage-gated ion channels has been a tremendous challenge for the pharmaceutical industry because channel activity is dependent on the transmembrane voltage gradient, a stimulus unlike ligand binding to G-protein-coupled receptors or ligand-gated ion channels. To achieve an acceptable throughput, assays to screen for voltage-gated ion channel modulators that are employed today rely on pharmacological intervention to activate these channels. These interventions can introduce artifacts. Ideally, a high-throughput screen should not compromise physiological relevance. Hence, a more appropriate method would activate voltage-gated ion channels by altering plasma membrane potential directly, via electrical stimulation, while simultaneously recordingthe operation of the channel in populations of cells. The authors present preliminary results obtained from a device that is designed to supply precise and reproducible electrical stimuli to populations of cells. Changes in voltage-gated ion channel activity were monitored using a digital fluorescent microscope. The prototype electric field stimulation (EFS) device provided real-time analysis of cellular responsiveness to physiological and pharmacological stimuli. Voltage stimuli applied to SK-N-SH neuroblastoma cells cultured on the EFS device evoked membrane potential changes that were dependent on activation of voltage-gated sodium channels. Data obtained using digital fluorescence microscopy suggests suitability of this system for HTS.

APA, Harvard, Vancouver, ISO, and other styles

42

Jinisha, B., K. M. Anilkumar, M. Manoj, A. Abhilash, V. S. Pradeep, and S. Jayalekshmi. "Poly (ethylene oxide) (PEO)-based, sodium ion-conducting‚ solid polymer electrolyte films, dispersed with Al2O3 filler, for applications in sodium ion cells." Ionics 24, no. 6 (November 9, 2017): 1675–83. http://dx.doi.org/10.1007/s11581-017-2332-2.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Berenbrink, M., and C. Bridges. "CATECHOLAMINE-ACTIVATED SODIUM/PROTON EXCHANGE IN THE RED BLOOD CELLS OF THE MARINE TELEOST GADUS MORHUA." Journal of Experimental Biology 192, no. 1 (July 1, 1994): 253–67. http://dx.doi.org/10.1242/jeb.192.1.253.

Full text

Abstract:

The effects of catecholamines on the pH and the cellular ion and water content were investigated in red blood cells from the Atlantic cod (Gadus morhua). Noradrenaline induced a rapid decrease in the extracellular pH (pHe) of red blood cells suspended in a CO2/bicarbonate or in a CO2/bicarbonate-free buffer system. The noradrenaline-induced changes in pHe were a saturable function of the external sodium ion concentration and were inhibited by amiloride but not by DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid, final concentration of both 10(-4) mol l-1). The catecholamine-induced extracellular acidification was accompanied by an intracellular alkalization and protons were moved from their electrochemical equilibrium. Proton extrusion was associated with an increase in the red blood cell sodium and chloride concentrations. In the presence of DIDS, the chloride movements were blocked and the net proton efflux under these conditions matched the net sodium influx. The results strongly suggested the activation of a sodium/proton exchanger by catecholamines in the red blood cells of the Atlantic cod. The red blood cell receptor affinity for adrenaline was three times higher than that for noradrenaline. Comparison with data in the literature for in vivo catecholamine concentrations indicated that adrenaline was more effective than noradrenaline in activating the red blood cell sodium/proton exchanger in the Atlantic cod in vivo.

APA, Harvard, Vancouver, ISO, and other styles

44

Rockley, Kim, Karen Jones, Ruth Roberts, and Michael Morton. "Electrophysiological analysis of seroquel’s activity in sodium ion channels, CiPA ion channels and hiPSC-neuronal cells." Journal of Pharmacological and Toxicological Methods 111 (September 2021): 106991. http://dx.doi.org/10.1016/j.vascn.2021.106991.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Xu, Siguang, Cui Liu, Yana Ma, Hong-Long Ji, and Xiumin Li. "Potential Roles of Amiloride-Sensitive Sodium Channels in Cancer Development." BioMed Research International 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/2190216.

Full text

Abstract:

The ENaC/degenerin ion channel superfamily includes the amiloride-sensitive epithelial sodium channel (ENaC) and acid sensitive ionic channel (ASIC). ENaC is a multimeric ion channel formed by heteromultimeric membrane glycoproteins, which participate in a multitude of biological processes by mediating the transport of sodium (Na+) across epithelial tissues such as the kidney, lungs, bladder, and gut. Aberrant ENaC functions contribute to several human disease states including pseudohypoaldosteronism, Liddle syndrome, cystic fibrosis, and salt-sensitive hypertension. Increasing evidence suggests that ion channels not only regulate ion homeostasis and electric signaling in excitable cells but also play important roles in cancer cell behaviors such as proliferation, apoptosis, invasion, and migration. Indeed, ENaCs/ASICs had been reported to be associated with cancer characteristics. Given their cell surface localization and pharmacology, pharmacological strategies to target ENaC/ASIC family members may be promising cancer therapeutics.

APA, Harvard, Vancouver, ISO, and other styles

46

Sparling, Richard, Laurel Thorlacius Holth, and Zhaosheng Lin. "Sodium ion dependent active transport of leucine in Methanosphaera stadtmanae." Canadian Journal of Microbiology 39, no. 8 (August 1, 1993): 749–53. http://dx.doi.org/10.1139/m93-110.

Full text

Abstract:

A Na+-dependent active transport system for leucine has been observed in Methanosphaera stadtmanae. The Km for leucine as determined was 20 μM with a Vmax of 3.2 nmol∙min−1∙mg protein−1. A minimum of 5 mM Na+ was required for optimal uptake rates. After correction for unspecific binding and incorporation into trichloroacetic acid precipitable materials, [14C]leucine was accumulated inside the cell to concentrations > 100 times higher than in the medium. The uptake of leucine into active cells was inhibited by the protonophore 3,3′,4′5-tetrachlorosalicylanilide but stimulated by the synthetic Na+–H+ antiporter monensin. A 500 mM NaCl pulse was able to drive leucine into resting cells. Of the amino acids tested, only valine and isoleucine competed effectively with leucine for transport.Key words: archaea, archaebacteria, methanogen, leucine transport, bioenergetics, sodium motive force.

APA, Harvard, Vancouver, ISO, and other styles

47

Roden, D. M., and A. L. George. "Structure and function of cardiac sodium and potassium channels." American Journal of Physiology-Heart and Circulatory Physiology 273, no. 2 (August 1, 1997): H511—H525. http://dx.doi.org/10.1152/ajpheart.1997.273.2.h511.

Full text

Abstract:

The application of patch-clamp and molecular approaches has resulted in an increasingly refined understanding of the molecular entities underlying cardiac sodium and potassium currents. The sodium current results from expression of a single large alpha-subunit, whereas multiple potassium currents and potassium channel alpha-subunits have been identified. Recapitulation of some ion currents in heterologous expression systems requires not only expression of alpha-subunits but also ancillary (beta) subunits. Domains common to functions such as activation, inactivation, and drug block are now being identified in alpha- and beta-gene products. Variability in the expression or function of individual ion-channel genes is an increasingly recognized source of variability in the ion currents recorded in heart cells under physiological conditions (e.g. during development) as well as in disease.

APA, Harvard, Vancouver, ISO, and other styles

48

Duszyk, Marek, Andrew S. French, and S. F. Paul Man. "Cystic fibrosis affects chloride and sodium channels in human airway epithelia." Canadian Journal of Physiology and Pharmacology 67, no. 10 (October 1, 1989): 1362–65. http://dx.doi.org/10.1139/y89-217.

Full text

Abstract:

Abnormalities of epithelial function in cystic fibrosis (CF) have been linked to defects in cell membrane permeability to chloride or sodium ions. Recently, a class of chloride channels in airway epithelial cells have been reported to lack their usual sensitivity to phosphorylation via cAMP-dependent protein kinase, suggesting that CF could be due to a single genetic defect in these channels. We have examined single chloride and sodium channels in control and CF human nasal epithelia using the patch-clamp technique. The most common chloride channel was not the one previously associated with CF, but it was also abnormal in CF cells. In addition, the number of sodium channels was unusually high in CF. These findings suggest a wider disturbance of ion channel properties in CF than would be produced by a defect in a single type of channel.Key words: ion channels, cystic fibrosis, airway, epithelium.

APA, Harvard, Vancouver, ISO, and other styles

49

Zhong, Yu, Xinhui Xia, Jiye Zhan, Xiuli Wang, and Jiangping Tu. "A CNT cocoon on sodium manganate nanotubes forming a core/branch cathode coupled with a helical carbon nanofibre anode for enhanced sodium ion batteries." Journal of Materials Chemistry A 4, no. 29 (2016): 11207–13. http://dx.doi.org/10.1039/c6ta05069g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Sigworth, F. J. "Voltage gating of ion channels." Quarterly Reviews of Biophysics 27, no. 1 (February 1994): 1–40. http://dx.doi.org/10.1017/s0033583500002894.

Full text

Abstract:

Voltage-gated ion channels are membrane proteins that play a central role in the propagation and transduction of cellular signals (Hille, 1992). Calcium ions entering cells through voltage-gated calcium channels serve as the trigger for neurotransmitter release, muscle contraction, and the release of hormones. Voltage-gated sodium channels initiate the nerve action potential and provide for its rapid propagation because the ion fluxes through these channels regeneratively cause more channels to open.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Sodium Ion Cells'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles