Functional coupling between sodium-activated potassium channels and voltage-dependent persistent sodium currents in cricket Kenyon cells.

PubMed

Takahashi, Izumi; Yoshino, Masami

2015-10-01

In this study, we examined the functional coupling between Na(+)-activated potassium (KNa) channels and Na(+) influx through voltage-dependent Na(+) channels in Kenyon cells isolated from the mushroom body of the cricket Gryllus bimaculatus. Single-channel activity of KNa channels was recorded with the cell-attached patch configuration. The open probability (Po) of KNa channels increased with increasing Na(+) concentration in a bath solution, whereas it decreased by the substitution of Na(+) with an equimolar concentration of Li(+). The Po of KNa channels was also found to be reduced by bath application of a high concentration of TTX (1 μM) and riluzole (100 μM), which inhibits both fast (INaf) and persistent (INaP) Na(+) currents, whereas it was unaffected by a low concentration of TTX (10 nM), which selectively blocks INaf. Bath application of Cd(2+) at a low concentration (50 μM), as an inhibitor of INaP, also decreased the Po of KNa channels. Conversely, bath application of the inorganic Ca(2+)-channel blockers Co(2+) and Ni(2+) at high concentrations (500 μM) had little effect on the Po of KNa channels, although Cd(2+) (500 μM) reduced the Po of KNa channels. Perforated whole cell clamp analysis further indicated the presence of sustained outward currents for which amplitude was dependent on the amount of Na(+) influx. Taken together, these results indicate that KNa channels could be activated by Na(+) influx passing through voltage-dependent persistent Na(+) channels. The functional significance of this coupling mechanism was discussed in relation to the membrane excitability of Kenyon cells and its possible role in the formation of long-term memory. Copyright © 2015 the American Physiological Society.

Sodium and phosphorus-based food additives: persistent but surmountable hurdles in the management of nutrition in chronic kidney disease

PubMed Central

Gutiérrez, Orlando M.

2012-01-01

Sodium and phosphorus-based food additives are among the most commonly consumed nutrients in the world. This is because both have diverse applications in processed food manufacturing, leading to their widespread utilization by the food industry. Since most foods are naturally low in salt, sodium additives almost completely account for the excessive consumption of sodium throughout the world. Similarly, phosphorus additives represent a major and “hidden” phosphorus load in modern diets. These factors pose a major barrier to successfully lowering sodium or phosphorus intake in patients with chronic kidney disease. As such, any serious effort to reduce sodium or phosphorus consumption will require reductions in the use of these additives by the food industry. The current regulatory environment governing the use of food additives does not favor this goal, however, in large part because these additives have historically been classified as generally safe for public consumption. To overcome these barriers, coordinated efforts will be needed to demonstrate that high intakes of these additives are not safe for public consumption and as such, should be subject to greater regulatory scrutiny. PMID:23439374

Sodium- and phosphorus-based food additives: persistent but surmountable hurdles in the management of nutrition in chronic kidney disease.

PubMed

Gutiérrez, Orlando M

2013-03-01

Sodium- and phosphorus-based food additives are among the most commonly consumed nutrients in the world. This is because both have diverse applications in processed food manufacturing, leading to their widespread use by the food industry. Since most foods are naturally low in salt, sodium additives almost completely account for the excessive consumption of sodium throughout the world. Similarly, phosphorus additives represent a major and "hidden" phosphorus load in modern diets. These factors pose a major barrier to successfully lowering sodium or phosphorus intake in patients with CKD. As such, any serious effort to reduce sodium or phosphorus consumption will require reductions in the use of these additives by the food industry. The current regulatory environment governing the use of food additives does not favor this goal, however, in large part because these additives have historically been classified as generally safe for public consumption. To overcome these barriers, coordinated efforts will be needed to demonstrate that high intake of these additives is not safe for public consumption and as such should be subject to greater regulatory scrutiny. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Effects of Different Oral Doses of Sodium Chloride on the Basal Acid-Base and Mineral Status of Exercising Horses Fed Low Amounts of Hay.

PubMed

Zeyner, Annette; Romanowski, Kristin; Vernunft, Andreas; Harris, Patricia; Müller, Ann-Marie; Wolf, Carola; Kienzle, Ellen

2017-01-01

The provision of NaCl, according to current recommendations, to horses in moderate work has been shown to induce immediate postprandial acidosis. The present study aimed to clarify whether this NaCl induced acidosis i) persists beyond the immediate postprandial period, and ii) is still present after a 2 week adaptation period. Six adult warmblood mares in moderate work received daily 1.00 kg hay per 100 kg body weight (bwt) only together with 0.64 kg unprocessed cereal grains/100 kg bwt.d as fed basis. Using a 3x3 Latin Square, either 0 (NaCl-0), 50 (NaCl-50) or 100 (NaCl-100) g NaCl/d were fed together with the concentrates in two equal doses for 3 weeks. During the final week, a mineral digestibility trial was undertaken. The middle sodium and chloride intake (NaCl-50) at least met the most common recommendations for moderate work. Morning (7:00 AM) urine and venous blood samples were collected on days 0, 1-4, 8, and 15, and analysed for pH, acid-base status, creatinine and electrolyte concentrations. Fractional electrolyte clearances (FC) were determined. Mean apparent sodium digestibility ranged between 60-62% whereas chloride digestibility was consistently above 94%. Supplementing 100 g but not 50 g of NaCl resulted in significant reduction of blood pH and base excess as well as urinary pH and urine acid excretion. Both 50 g and 100 g NaCl supplementation caused a significant reduction in base and net acid-base excretion, urine density and potassium concentration, but increased urine sodium concentration and the FC of sodium and chloride (P < 0.05). This suggests that a high proportion of the recommended salt doses is excreted renally. The above effects of NaCl supplementation persisted over the 2 week measurement period. Results suggest that feeding 100 g NaCl to moderately exercising horses results in mild metabolic acidosis, whereas feeding 50 g according to current recommendations resulted in compensated acidosis.

Effects of Different Oral Doses of Sodium Chloride on the Basal Acid-Base and Mineral Status of Exercising Horses Fed Low Amounts of Hay

PubMed Central

Zeyner, Annette; Romanowski, Kristin; Vernunft, Andreas; Harris, Patricia; Müller, Ann-Marie; Wolf, Carola; Kienzle, Ellen

2017-01-01

The provision of NaCl, according to current recommendations, to horses in moderate work has been shown to induce immediate postprandial acidosis. The present study aimed to clarify whether this NaCl induced acidosis i) persists beyond the immediate postprandial period, and ii) is still present after a 2 week adaptation period. Six adult warmblood mares in moderate work received daily 1.00 kg hay per 100 kg body weight (bwt) only together with 0.64 kg unprocessed cereal grains/100 kg bwt.d as fed basis. Using a 3x3 Latin Square, either 0 (NaCl-0), 50 (NaCl-50) or 100 (NaCl-100) g NaCl/d were fed together with the concentrates in two equal doses for 3 weeks. During the final week, a mineral digestibility trial was undertaken. The middle sodium and chloride intake (NaCl-50) at least met the most common recommendations for moderate work. Morning (7:00 AM) urine and venous blood samples were collected on days 0, 1–4, 8, and 15, and analysed for pH, acid-base status, creatinine and electrolyte concentrations. Fractional electrolyte clearances (FC) were determined. Mean apparent sodium digestibility ranged between 60–62% whereas chloride digestibility was consistently above 94%. Supplementing 100 g but not 50 g of NaCl resulted in significant reduction of blood pH and base excess as well as urinary pH and urine acid excretion. Both 50 g and 100 g NaCl supplementation caused a significant reduction in base and net acid-base excretion, urine density and potassium concentration, but increased urine sodium concentration and the FC of sodium and chloride (P < 0.05). This suggests that a high proportion of the recommended salt doses is excreted renally. The above effects of NaCl supplementation persisted over the 2 week measurement period. Results suggest that feeding 100 g NaCl to moderately exercising horses results in mild metabolic acidosis, whereas feeding 50 g according to current recommendations resulted in compensated acidosis. PMID:28045916

Quantitative analysis of the persistent photoconductivity effect in Cu(In,Ga)Se2

NASA Astrophysics Data System (ADS)

Maciaszek, Marek; Zabierowski, Paweł

2018-04-01

The magnitude of the persistent photoconductivity effect (PPC) in two sets of Cu(In,Ga)Se2 samples, differing in the amount of cadmium and sodium, was measured. Using equations describing the magnitude of PPC, metastable defect and shallow acceptor densities were calculated. The method of the analysis of PPC in the presence of a deep acceptor level was presented. Based on obtained results, we drew conclusions about reasons of decreased PPC in Cu(In,Ga)Se2 without sodium as well as the role of (VSe-VCu) complexes in establishing the carrier concentration in Cu(In,Ga)Se2 with and without sodium.

[Low extracellular pH increases the persistent sodium current in guinea pig ventricular myocytes].

PubMed

Ma, Ji-Hua; Luo, An-Tao; Wang, Wei-Ping; Zhang, Pei-Hua

2007-04-25

Whole-cell and cell-attached patch-clamp techniques were used to record the changes of persistent sodium current (I(Na.P)) in ventricular myocytes of guinea pig to investigate the effect of low extracellular pH on I(Na.P) and its mechanism. The results showed that low extracellular pH (7.0, 6.8 and 6.5) obviously increased the amplitude of whole-cell I(Na.P) in a [H(+)] concentration-dependent manner. Under the condition of extracellular pH 6.5, I(Na.P) was markedly augmented from control (pH 7.4) value of (0.347+/-0.067) pA/pF to (0.817+/- 0.137) pA/pF (P<0.01, n=6), whereas the reducing agent dithiothreitiol (DTT, 1 mmol/L) reversed the increased IN(Na.P) from (0.817+/-0.137) pA/pF to (0.233+/-0.078) pA/pF (P<0.01 vs pH 6.5, n=6). Decreasing extracellular pH to 6.5 also increased the persistent sodium channel activity in cell-attached patches. The mean open probability and mean open time were increased from control value of 0.021+/-0.007 and (0.899+/-0.074) ms to 0.205+/-0.023 and (1.593+/-0.158) ms, respectively (both P<0.01, n=6), and such enhancement was reversed by application of 1 mmol/L DTT [to 0.019+/-0.005 and (0.868+/-0.190) ms, both P<0.01 vs pH 6.5, n=6]. Furthermore, protein kinase C (PKC) inhibitor bisindolylmaleimide (BIM, 5 micromol/L) reduced the enhanced mean open probability and mean open time at pH 6.5 from 0.214+/-0.024 and (1.634+/-0.137) ms to 0.025+/-0.006 and (0.914+/-0.070) ms, respectively (both P<0.01 vs pH 6.5, n=6). The results demonstrate that low extracellular pH markedly increases I(Na.P) in guinea pig ventricular myocytes, in which activation of PKC may be involved.

The human Nav1.5 F1486 deletion associated with long QT syndrome leads to impaired sodium channel inactivation and reduced lidocaine sensitivity

PubMed Central

Song, Weihua; Xiao, Yucheng; Chen, Hanying; Ashpole, Nicole M; Piekarz, Andrew D; Ma, Peilin; Hudmon, Andy; Cummins, Theodore R; Shou, Weinian

2012-01-01

The deletion of phenylalanine 1486 (F1486del) in the human cardiac voltage-gated sodium channel (hNav1.5) is associated with fatal long QT (LQT) syndrome. In this study we determined how F1486del impairs the functional properties of hNav1.5 and alters action potential firing in heterologous expression systems (human embryonic kidney (HEK) 293 cells) and their native cardiomyocyte background. Cells expressing hNav1.5-F1486del exhibited a loss-of-function alteration, reflected by an 80% reduction of peak current density, and several gain-of-function alterations, including reduced channel inactivation, enlarged window current, substantial augmentation of persistent late sodium current and an increase in ramp current. We also observed substantial action potential duration (APD) prolongation and prominent early afterdepolarizations (EADs) in neonatal cardiomyocytes expressing the F1486del channels, as well as in computer simulations of myocyte activity. In addition, lidocaine sensitivity was dramatically reduced, which probably contributed to the poor therapeutic outcome observed in the patient carrying the hNav1.5-F1486del mutation. Therefore, despite the significant reduction in peak current density, the F1486del mutation also leads to substantial gain-of-function alterations that are sufficient to cause APD prolongation and EADs, the predominant characteristic of LQTs. These data demonstrate that hNav1.5 mutations can have complex functional consequences and highlight the importance of identifying the specific molecular defect when evaluating potential treatments for individuals with prolonged QT intervals. PMID:22826127

Intrinsic membrane plasticity via increased persistent sodium conductance of cholinergic neurons in the rat laterodorsal tegmental nucleus contributes to cocaine-induced addictive behavior.

PubMed

Kamii, Hironori; Kurosawa, Ryo; Taoka, Naofumi; Shinohara, Fumiya; Minami, Masabumi; Kaneda, Katsuyuki

2015-05-01

The laterodorsal tegmental nucleus (LDT) is a brainstem nucleus implicated in reward processing and is one of the main sources of cholinergic afferents to the ventral tegmental area (VTA). Neuroplasticity in this structure may affect the excitability of VTA dopamine neurons and mesocorticolimbic circuitry. Here, we provide evidence that cocaine-induced intrinsic membrane plasticity in LDT cholinergic neurons is involved in addictive behaviors. After repeated experimenter-delivered cocaine exposure, ex vivo whole-cell recordings obtained from LDT cholinergic neurons revealed an induction of intrinsic membrane plasticity in regular- but not burst-type neurons, resulting in increased firing activity. Pharmacological examinations showed that increased riluzole-sensitive persistent sodium currents, but not changes in Ca(2+) -activated BK, SK or voltage-dependent A-type potassium conductance, mediated this plasticity. In addition, bilateral microinjection of riluzole into the LDT immediately before the test session in a cocaine-induced conditioned place preference (CPP) paradigm inhibited the expression of cocaine-induced CPP. These findings suggest that intrinsic membrane plasticity in LDT cholinergic neurons is causally involved in the development of cocaine-induced addictive behaviors. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Augmented sodium currents contribute to the enhanced excitability of small diameter capsaicin-sensitive sensory neurons isolated from Nf1+/⁻ mice.

PubMed

Wang, Yue; Duan, J-H; Hingtgen, C M; Nicol, G D

2010-04-01

Neurofibromin, the product of the Nf1 gene, is a guanosine triphosphatase activating protein (GAP) for p21ras (Ras) that accelerates conversion of active Ras-GTP to inactive Ras-GDP. Sensory neurons with reduced levels of neurofibromin likely have augmented Ras-GTP activity. We reported previously that sensory neurons isolated from a mouse model with a heterozygous mutation of the Nf1 gene (Nf1+/⁻) exhibited greater excitability compared with wild-type mice. To determine the mechanism giving rise to the augmented excitability, differences in specific membrane currents were examined. Consistent with the enhanced excitability of Nf1+/⁻ neurons, peak current densities of both tetrodotoxin-resistant sodium current (TTX-R I(Na)) and TTX-sensitive (TTX-S) I(Na) were significantly larger in Nf1+/⁻ than in wild-type neurons. Although the voltages for half-maximal activation (V(0.5)) were not different, there was a significant depolarizing shift in the V(0.5) for steady-state inactivation of both TTX-R and TTX-S I(Na) in Nf1+/⁻ neurons. In addition, levels of persistent I(Na) were significantly larger in Nf1+/⁻ neurons. Neither delayed rectifier nor A-type potassium currents were altered in Nf1+/⁻ neurons. These results demonstrate that enhanced production of action potentials in Nf1+/⁻ neurons results, in part, from larger current densities and a depolarized voltage dependence of steady-state inactivation for I(Na) that potentially leads to a greater availability of sodium channels at voltages near the firing threshold for the action potential.

Computational Reconstruction of Pacemaking and Intrinsic Electroresponsiveness in Cerebellar Golgi Cells

PubMed Central

Solinas, Sergio; Forti, Lia; Cesana, Elisabetta; Mapelli, Jonathan; De Schutter, Erik; D'Angelo, Egidio

2007-01-01

The Golgi cells have been recently shown to beat regularly in vitro (Forti et al., 2006. J. Physiol. 574, 711–729). Four main currents were shown to be involved, namely a persistent sodium current (I Na-p), an h current (I h), an SK-type calcium-dependent potassium current (I K-AHP), and a slow M-like potassium current (I K-slow). These ionic currents could take part, together with others, also to different aspects of neuronal excitability like responses to depolarizing and hyperpolarizing current injection. However, the ionic mechanisms and their interactions remained largely hypothetical. In this work, we have investigated the mechanisms of Golgi cell excitability by developing a computational model. The model predicts that pacemaking is sustained by subthreshold oscillations tightly coupled to spikes. I Na-p and I K-slow emerged as the critical determinants of oscillations. I h also played a role by setting the oscillatory mechanism into the appropriate membrane potential range. I K-AHP, though taking part to the oscillation, appeared primarily involved in regulating the ISI following spikes. The combination with other currents, in particular a resurgent sodium current (I Na-r) and an A-current (I K-A), allowed a precise regulation of response frequency and delay. These results provide a coherent reconstruction of the ionic mechanisms determining Golgi cell intrinsic electroresponsiveness and suggests important implications for cerebellar signal processing, which will be fully developed in a companion paper (Solinas et al., 2008. Front. Neurosci. 2:4). PMID:18946520

Functional up-regulation of Nav1.8 sodium channel in Aβ afferent fibers subjected to chronic peripheral inflammation

PubMed Central

2014-01-01

Background Functional alterations in the properties of Aβ afferent fibers may account for the increased pain sensitivity observed under peripheral chronic inflammation. Among the voltage-gated sodium channels involved in the pathophysiology of pain, Nav1.8 has been shown to participate in the peripheral sensitization of nociceptors. However, to date, there is no evidence for a role of Nav1.8 in controlling Aβ-fiber excitability following persistent inflammation. Methods Distribution and expression of Nav1.8 in dorsal root ganglia and sciatic nerves were qualitatively or quantitatively assessed by immunohistochemical staining and by real time-polymerase chain reaction at different time points following complete Freund’s adjuvant (CFA) administration. Using a whole-cell patch-clamp configuration, we further determined both total INa and TTX-R Nav1.8 currents in large-soma dorsal root ganglia (DRG) neurons isolated from sham or CFA-treated rats. Finally, we analyzed the effects of ambroxol, a Nav1.8-preferring blocker on the electrophysiological properties of Nav1.8 currents and on the mechanical sensitivity and inflammation of the hind paw in CFA-treated rats. Results Our findings revealed that Nav1.8 is up-regulated in NF200-positive large sensory neurons and is subsequently anterogradely transported from the DRG cell bodies along the axons toward the periphery after CFA-induced inflammation. We also demonstrated that both total INa and Nav1.8 peak current densities are enhanced in inflamed large myelinated Aβ-fiber neurons. Persistent inflammation leading to nociception also induced time-dependent changes in Aβ-fiber neuron excitability by shifting the voltage-dependent activation of Nav1.8 in the hyperpolarizing direction, thus decreasing the current threshold for triggering action potentials. Finally, we found that ambroxol significantly reduces the potentiation of Nav1.8 currents in Aβ-fiber neurons observed following intraplantar CFA injection and concomitantly blocks CFA-induced mechanical allodynia, suggesting that Nav1.8 regulation in Aβ-fibers contributes to inflammatory pain. Conclusions Collectively, these findings support a key role for Nav1.8 in controlling the excitability of Aβ-fibers and its potential contribution to the development of mechanical allodynia under persistent inflammation. PMID:24606981

Dominant frequency increase rate predicts transition from paroxysmal to long-term persistent atrial fibrillation.

PubMed

Martins, Raphael P; Kaur, Kuljeet; Hwang, Elliot; Ramirez, Rafael J; Willis, B Cicero; Filgueiras-Rama, David; Ennis, Steven R; Takemoto, Yoshio; Ponce-Balbuena, Daniela; Zarzoso, Manuel; O'Connell, Ryan P; Musa, Hassan; Guerrero-Serna, Guadalupe; Avula, Uma Mahesh R; Swartz, Michael F; Bhushal, Sandesh; Deo, Makarand; Pandit, Sandeep V; Berenfeld, Omer; Jalife, José

2014-04-08

Little is known about the mechanisms underlying the transition from paroxysmal to persistent atrial fibrillation (AF). In an ovine model of long-standing persistent AF we tested the hypothesis that the rate of electric and structural remodeling, assessed by dominant frequency (DF) changes, determines the time at which AF becomes persistent. Self-sustained AF was induced by atrial tachypacing. Seven sheep were euthanized 11.5±2.3 days after the transition to persistent AF and without reversal to sinus rhythm; 7 sheep were euthanized after 341.3±16.7 days of long-standing persistent AF. Seven sham-operated animals were in sinus rhythm for 1 year. DF was monitored continuously in each group. Real-time polymerase chain reaction, Western blotting, patch clamping, and histological analyses were used to determine the changes in functional ion channel expression and structural remodeling. Atrial dilatation, mitral valve regurgitation, myocyte hypertrophy, and atrial fibrosis occurred progressively and became statistically significant after the transition to persistent AF, with no evidence for left ventricular dysfunction. DF increased progressively during the paroxysmal-to-persistent AF transition and stabilized when AF became persistent. Importantly, the rate of DF increase correlated strongly with the time to persistent AF. Significant action potential duration abbreviation, secondary to functional ion channel protein expression changes (CaV1.2, NaV1.5, and KV4.2 decrease; Kir2.3 increase), was already present at the transition and persisted for 1 year of follow up. In the sheep model of long-standing persistent AF, the rate of DF increase predicts the time at which AF stabilizes and becomes persistent, reflecting changes in action potential duration and densities of sodium, L-type calcium, and inward rectifier currents.

Mechanisms contributing to the dopamine induction of crawl-like bursting in leech motoneurons.

PubMed

Crisp, Kevin M; Gallagher, Brian R; Mesce, Karen A

2012-09-01

Dopamine (DA) activates fictive crawling behavior in the medicinal leech. To identify the cellular mechanisms underlying this activation at the level of crawl-specific motoneuronal bursting, we targeted potential cAMP-dependent events that are often activated through DA(1)-like receptor signaling pathways. We found that isolated ganglia produced crawl-like motoneuron bursting after bath application of phosphodiesterase inhibitors (PDIs) that upregulated cAMP. This bursting persisted in salines in which calcium ions were replaced with equimolar cobalt or nickel, but was blocked by riluzole, an inhibitor of a persistent sodium current. PDI-induced bursting contained a number of patterned elements that were statistically similar to those observed during DA-induced fictive crawling, except that one motoneuron (CV) exhibited bursting during the contraction rather than the elongation phase of crawling. Although DA and the PDIs produced similar bursting profiles, intracellular recordings from motoneurons revealed differences in altered membrane properties. For example, DA lowered motoneuron excitability whereas the PDIs increased resting discharge rates. We suggest that PDIs (and DA) activate a sodium-influx-dependent timing mechanism capable of setting the crawl rhythm and that multiple DA receptor subtypes are involved in shaping and modulating the phase relationships and membrane properties of cell-specific members of the crawl network to generate crawling.

Hyperpolarization-Activated Current Induces Period-Doubling Cascades and Chaos in a Cold Thermoreceptor Model

PubMed Central

Xu, Kesheng; Maidana, Jean P.; Caviedes, Mauricio; Quero, Daniel; Aguirre, Pablo; Orio, Patricio

2017-01-01

In this article, we describe and analyze the chaotic behavior of a conductance-based neuronal bursting model. This is a model with a reduced number of variables, yet it retains biophysical plausibility. Inspired by the activity of cold thermoreceptors, the model contains a persistent Sodium current, a Calcium-activated Potassium current and a hyperpolarization-activated current (Ih) that drive a slow subthreshold oscillation. Driven by this oscillation, a fast subsystem (fast Sodium and Potassium currents) fires action potentials in a periodic fashion. Depending on the parameters, this model can generate a variety of firing patterns that includes bursting, regular tonic and polymodal firing. Here we show that the transitions between different firing patterns are often accompanied by a range of chaotic firing, as suggested by an irregular, non-periodic firing pattern. To confirm this, we measure the maximum Lyapunov exponent of the voltage trajectories, and the Lyapunov exponent and Lempel-Ziv's complexity of the ISI time series. The four-variable slow system (without spiking) also generates chaotic behavior, and bifurcation analysis shows that this is often originated by period doubling cascades. Either with or without spikes, chaos is no longer generated when the Ih is removed from the system. As the model is biologically plausible with biophysically meaningful parameters, we propose it as a useful tool to understand chaotic dynamics in neurons. PMID:28344550

Light scattering measurement of sodium polyacrylate products

NASA Astrophysics Data System (ADS)

Lama, Nisha; Norwood, David; Boone, Steven; Massie-Boyer, Valerie

2015-03-01

In the presentation, we will describe the use of a multi-detector HPLC incorporating the DAWN EOS multi-angle laser light scattering (MALLS) detector to measure the properties such as molecular weight, RMS radius, contour and persistence length and polydispersity of sodium polyacrylate products. The samples of sodium polyacrylate are used in various industries as thickening agents, coating dispersants, artificial snow, laundry detergent and disposable diapers. Data and results obtained from the experiment will be presented.

The interplay of seven subthreshold conductances controls the resting membrane potential and the oscillatory behavior of thalamocortical neurons

PubMed Central

Zagha, Edward; Mato, German; Rudy, Bernardo; Nadal, Marcela S.

2014-01-01

The signaling properties of thalamocortical (TC) neurons depend on the diversity of ion conductance mechanisms that underlie their rich membrane behavior at subthreshold potentials. Using patch-clamp recordings of TC neurons in brain slices from mice and a realistic conductance-based computational model, we characterized seven subthreshold ion currents of TC neurons and quantified their individual contributions to the total steady-state conductance at levels below tonic firing threshold. We then used the TC neuron model to show that the resting membrane potential results from the interplay of several inward and outward currents over a background provided by the potassium and sodium leak currents. The steady-state conductances of depolarizing Ih (hyperpolarization-activated cationic current), IT (low-threshold calcium current), and INaP (persistent sodium current) move the membrane potential away from the reversal potential of the leak conductances. This depolarization is counteracted in turn by the hyperpolarizing steady-state current of IA (fast transient A-type potassium current) and IKir (inwardly rectifying potassium current). Using the computational model, we have shown that single parameter variations compatible with physiological or pathological modulation promote burst firing periodicity. The balance between three amplifying variables (activation of IT, activation of INaP, and activation of IKir) and three recovering variables (inactivation of IT, activation of IA, and activation of Ih) determines the propensity, or lack thereof, of repetitive burst firing of TC neurons. We also have determined the specific roles that each of these variables have during the intrinsic oscillation. PMID:24760784

Synergetic Action of Domain II and IV Underlies Persistent Current Generation in Nav1.3 as revealed by a tarantula toxin

PubMed Central

Tang, Cheng; Zhou, Xi; Zhang, Yunxiao; xiao, Zhaohua; Hu, Zhaotun; Zhang, Changxin; Huang, Ying; Chen, Bo; Liu, Zhonghua; Liang, Songping

2015-01-01

The persistent current (INaP) through voltage-gated sodium channels enhances neuronal excitability by causing prolonged depolarization of membranes. Nav1.3 intrinsically generates a small INaP, although the mechanism underlying its generation remains unclear. In this study, the involvement of the four domains of Nav1.3 in INaP generation was investigated using the tarantula toxin α-hexatoxin-MrVII (RTX-VII). RTX-VII activated Nav1.3 and induced a large INaP. A pre-activated state binding model was proposed to explain the kinetics of toxin-channel interaction. Of the four domains of Nav1.3, both domain II and IV might play important roles in the toxin-induced INaP. Domain IV constructed the binding site for RTX-VII, while domain II might not participate in interacting with RTX-VII but could determine the efficacy of RTX-VII. Our results based on the use of RTX-VII as a probe suggest that domain II and IV cooperatively contribute to the generation of INaP in Nav1.3. PMID:25784299

Urease-independent chemotactic responses of Helicobacter pylori to urea, urease inhibitors, and sodium bicarbonate.

PubMed Central

Mizote, T; Yoshiyama, H; Nakazawa, T

1997-01-01

Helicobacter pylori CPY3401 and an isogenic urease-negative mutant, HPT73, showed chemotactic responses to urea, flurofamide (a potent urease inhibitor), and sodium bicarbonate. Since urea and sodium bicarbonate are secreted through the gastric epithelial surface and hydrolysis of urea by urease on the bacterial surface is essential for colonization, the chemotactic response of H. pylori may be crucial for its colonization and persistence in the stomach. PMID:9119496

Long-term Taenia saginata infection successfully treated with meglumine/diatrizoate sodium.

PubMed

Hirasaki, Shoji; Murakami, Kazutoshi; Mizushima, Takaaki; Hiramatsu, Kazuhisa; Hanayama, Yoshihisa; Kanamori, Tatsuya; Koide, Norio

2012-01-01

A 46-year-old Japanese man visited our hospital for chronic abdominal pain, persistent diarrhea and discharge of proglottids for 7 years. He had been living in Lao People's Democratic Republic. Ileography using meglumine/diatrizoate sodium (Gastrografin) revealed a long tapeworm. A Taenia saginata including the scolex was excreted through the intestinal tract by the administration of total 780 ml of Gastrografin. Taeniasis is an important disease in the differential diagnosis of imported diseases in Japan. Parasite infection should be suspected in patients with chronic abdominal pain or persistent diarrhea regardless of the findings for small bowel obstruction when there is a history of overseas travel.

Qualitative validation of the reduction from two reciprocally coupled neurons to one self-coupled neuron in a respiratory network model.

PubMed

Dunmyre, Justin R

2011-06-01

The pre-Bötzinger complex of the mammalian brainstem is a heterogeneous neuronal network, and individual neurons within the network have varying strengths of the persistent sodium and calcium-activated nonspecific cationic currents. Individually, these currents have been the focus of modeling efforts. Previously, Dunmyre et al. (J Comput Neurosci 1-24, 2011) proposed a model and studied the interactions of these currents within one self-coupled neuron. In this work, I consider two identical, reciprocally coupled model neurons and validate the reduction to the self-coupled case. I find that all of the dynamics of the two model neuron network and the regions of parameter space where these distinct dynamics are found are qualitatively preserved in the reduction to the self-coupled case.

Unusual Voltage-Gated Sodium Currents as Targets for Pain.

PubMed

Barbosa, C; Cummins, T R

2016-01-01

Pain is a serious health problem that impacts the lives of many individuals. Hyperexcitability of peripheral sensory neurons contributes to both acute and chronic pain syndromes. Because voltage-gated sodium currents are crucial to the transmission of electrical signals in peripheral sensory neurons, the channels that underlie these currents are attractive targets for pain therapeutics. Sodium currents and channels in peripheral sensory neurons are complex. Multiple-channel isoforms contribute to the macroscopic currents in nociceptive sensory neurons. These different isoforms exhibit substantial variations in their kinetics and pharmacology. Furthermore, sodium current complexity is enhanced by an array of interacting proteins that can substantially modify the properties of voltage-gated sodium channels. Resurgent sodium currents, atypical currents that can enhance recovery from inactivation and neuronal firing, are increasingly being recognized as playing potentially important roles in sensory neuron hyperexcitability and pain sensations. Here we discuss unusual sodium channels and currents that have been identified in nociceptive sensory neurons, describe what is known about the molecular determinants of the complex sodium currents in these neurons. Finally, we provide an overview of therapeutic strategies to target voltage-gated sodium currents in nociceptive neurons. Copyright © 2016 Elsevier Inc. All rights reserved.

Sodium channel dysfunction in intractable childhood epilepsy with generalized tonic–clonic seizures

PubMed Central

Rhodes, Thomas H; Vanoye, Carlos G; Ohmori, Iori; Ogiwara, Ikuo; Yamakawa, Kazuhiro; George, Alfred L

2005-01-01

Mutations in SCN1A, the gene encoding the brain voltage-gated sodium channel α1 subunit (NaV1.1), are associated with genetic forms of epilepsy, including generalized epilepsy with febrile seizures plus (GEFS+ type 2), severe myoclonic epilepsy of infancy (SMEI) and related conditions. Several missense SCN1A mutations have been identified in probands affected by the syndrome of intractable childhood epilepsy with generalized tonic–clonic seizures (ICEGTC), which bears similarity to SMEI. To test whether ICEGTC arises from molecular mechanisms similar to those involved in SMEI, we characterized eight ICEGTC missense mutations by whole-cell patch clamp recording of recombinant human SCN1A heterologously expressed in cultured mammalian cells. Two mutations (G979R and T1709I) were non-functional. The remaining alleles (T808S, V983A, N1011I, V1611F, P1632S and F1808L) exhibited measurable sodium current, but had heterogeneous biophysical phenotypes. Mutant channels exhibited lower (V983A, N1011I and F1808L), greater (T808S) or similar (V1611F and P1632S) peak sodium current densities compared with wild-type (WT) SCN1A. Three mutations (V1611F, P1632S and F1808L) displayed hyperpolarized conductance–voltage relationships, while V983A exhibited a strong depolarizing shift in the voltage dependence of activation. All mutants except T808S had hyperpolarized shifts in the voltage dependence of steady-state channel availability. Three mutants (V1611F, P1632S and F1808L) exhibited persistent sodium current ranging from ∼1–3% of peak current amplitude that was significantly greater than WT-SCN1A. Several mutants had impaired slow inactivation, with V983A showing the most prominent effect. Finally, all of the functional alleles exhibited reduced use-dependent channel inhibition. In summary, SCN1A mutations associated with ICEGTC result in a wide spectrum of biophysical defects, including mild-to-moderate gating impairments, shifted voltage dependence and reduced use dependence. The constellation of biophysical abnormalities for some mutants is distinct from those previously observed for GEFS+ and SMEI, suggesting possible, but complex, genotype–phenotype correlations. PMID:16210358

Sodium efflux from voltage clamped squid giant axons.

PubMed Central

Landowne, D

1977-01-01

1. The efflux of radioactive sodium was measured from squid axons during simultaneous voltage clamp experiments such that it was possible to determine the efflux of sodium associated with a measured voltage clamp current. 2. The extra efflux of sodium associated with voltage clamp pulses increased linearly with the magnitude of the depolarization above 40 mV. A 100 mV pulse of sufficient duration to produce all of the sodium current increased the rate constant of efflux by about 10(-6). 3. Application of 100 nM tetrodotoxin eliminated the sodium current and the extra efflux of radioactive sodium. 4. Cooling the axon increased the extra efflux/voltage clamp pulse slightly with a Q10 of 1/1-1. On the same axons cooling increased the integral of the sodium current with a Q10 of 1/1-4. 5. Replacing external sodium with Tris, dextrose or Mg-mannitol reduced the extra efflux of sodium by about 50%. The inward sodium current was replaced with an outward current as expected. 6. Replacing external sodium with lithium also reduced the extra efflux by about 50% but the currents seen in lithium were slightly larger than those in sodium. 7. The effect of replacing external sodium was not voltage dependent. Cooling reduced the effect so that there was less reduction of efflux on switching to Tris ASW in the cold than in the warm. 8. The extra efflux of sodium into sodium-free ASW is approximately the same as the integral of the sodium current. Adding external sodium produces a deviation from the independence principle such that there is more exchange of sodium than predicted. Such a deviation from prediction was noted by Hodgkin & Huxley (1952c). 9. Using the equations of Hodgkin & Huxley (1952c) modified to include the deviation from independence reported in this paper and its temperature dependence, one can predict the temperature dependence of the sodium efflux associated with action potentials and obtain much better agreement than is possibly without these phenomena. 10. This deviation from independence in the sodium fluxes is the type expected from some kind of mixing and binding of sodium within the membrane phase. PMID:856999

Lactase persistence and augmented salivary alpha-amylase gene copy numbers might have been selected by the combined toxic effects of gluten and (food born) pathogens.

PubMed

Pruimboom, Leo; Fox, Tom; Muskiet, Frits A J

2014-03-01

Various positively selected adaptations to new nutrients have been identified. Lactase persistence is among the best known, conferring the ability for drinking milk at post weaning age. An augmented number of amylase gene (AMY1) copies, giving rise to higher salivary amylase activity, has been implicated in the consumption of starch-rich foods. Higher AMY1 copy numbers have been demonstrated in populations with recent histories of starchy-rich diets. It is however questionable whether the resulting polymorphisms have exerted positive selection only by providing easily available sources of macro and micronutrients. Humans have explored new environments more than any other animal. Novel environments challenge the host, but especially its immune system with new climatic conditions, food and especially pathogens. With the advent of the agricultural revolution and the concurrent domestication of cattle came new pathogens. We contend that specific new food ingredients (e.g., gluten) and novel pathogens drove selection for lactase persistence and higher AMY gene copy numbers. Both adaptations provide ample glucose for activating the sodium glucose-dependent co-transporter 1 (SGLT1), which is the principal glucose, sodium and water transporter in the gastro-intestinal tract. Their rapid uptake confers protection against potentially lethal dehydration, hyponatremia and ultimately multiple organ failure. Oral rehydration therapy aims at SGLT1 activity and is the current treatment of choice for chronic diarrhoea and vomiting. We hypothesize that lifelong lactase activity and rapid starch digestion should be looked at as the evolutionary covalent of oral rehydration therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impaired sodium-dependent adaptation of arterial stiffness in formerly preeclamptic women: the RETAP-vascular study.

PubMed

van der Graaf, Anne Marijn; Paauw, Nina D; Toering, Tsjitske J; Feelisch, Martin; Faas, Marijke M; Sutton, Thomas R; Minnion, Magdalena; Lefrandt, Joop D; Scherjon, Sicco A; Franx, Arie; Navis, Gerjan; Lely, A Titia

2016-06-01

Women with a history of preeclampsia have an increased risk for cardiovascular diseases later in life. Persistent vascular alterations in the postpartum period might contribute to this increased risk. The current study assessed arterial stiffness under low sodium (LS) and high sodium (HS) conditions in a well-characterized group of formerly early-onset preeclamptic (fPE) women and formerly pregnant (fHP) women. Eighteen fHP and 18 fPE women were studied at an average of 5 yr after pregnancy on 1 wk of LS (50 mmol Na(+)/day) and 1 wk of HS (200 mmol Na(+)/day) intake. Arterial stiffness was measured by pulse-wave analysis (aortic augmentation index, AIx) and carotid-femoral pulse-wave velocity (PWV). Circulating markers of the renin-angiotensin aldosterone system (RAAS), extracellular volume (ECV), nitric oxide (NO), and hydrogen sulfide (H2S) were measured in an effort to identify potential mechanistic elements underlying adaptation of arterial stiffness. AIx was significantly lower in fHP women on LS compared with HS while no difference in AIx was apparent in fPE women. PWV remained unchanged upon different sodium loads in either group. Comparable sodium-dependent changes in RAAS, ECV, and NO/H2S were observed in fHP and fPE women. fPE women have an impaired ability to adapt their arterial stiffness in response to changes in sodium intake, independently of blood pressure, RAAS, ECV, and NO/H2S status. The pathways involved in impaired adaptation of arterial stiffness, and its possible contribution to the increased long-term risk for cardiovascular diseases in fPE women, remain to be investigated. Copyright © 2016 the American Physiological Society.

FeO "Orange Arc" Emission Detected in Optical Spectrum of Leonid Persistent Trains

NASA Technical Reports Server (NTRS)

Jenniskens, Peter; Lacey, Matt; Allan, Beverly J.; Self, Daniel E.; Plane, John M. C.; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

We report the detection of a broad continuum emission dominating the visual spectrum of a Leonid persistent train. A comparison with laboratory spectra of FeO 1 "orange arc" emission at I mbar shows a general agreement of the band position and shape. The detection of FeO confirms the classical mechanism of metal atom catalyzed recombination of ozone and oxygen atoms as the driving force behind optical emission from persistent trains. Sodium and iron atoms are now confirmed catalysts.

A Cold-Pole Enhancement in Mercury’s Sodium Exosphere

PubMed Central

Cassidy, Timothy A.; McClintock, William E.; Killen, Rosemary M.; Sarantos, Menelaos; Merkel, Aimee W.; Vervack, Ronald J.; Burger, Matthew H.

2018-01-01

The Ultraviolet and Visible Spectrometer (UVVS) component of the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) on the MESSENGER spacecraft characterized the local-time distribution of the sodium exosphere over the course of its orbital mission. The observations show that the sodium exosphere is enhanced above Mercury’s cold-pole longitudes. Based on previously published sodium exosphere models we infer that these regions act as nightside surface reservoirs, temporary sinks to the exosphere that collect sodium atoms transported anti-sunward. The reservoirs are revealed as exospheric enhancements when they are exposed to sunlight. As in the models the reservoir is depleted as the cold poles rotate from dawn to dusk, but unlike the models the depletion is only partial. The persistence of the reservoir means that it could, over the course of geologically long periods of time, contribute to an increase in the bulk concentration of sodium near the cold-pole longitudes. PMID:29720774

Sodium accumulation at potential-induced degradation shunted areas in polycrystalline silicon modules

DOE PAGES

Harvey, Steven P.; Aguiar, Jeffery A.; Hacke, Peter; ...

2016-09-19

Here, we investigated potential-induced degradation (PID) in silicon mini-modules that were subjected to accelerated stressing to induce PID conditions. Shunted areas on the cells were identified with photoluminescence and dark lock-in thermography (DLIT) imaging. The identical shunted areas were then analyzed via time-of-flight secondary-ion mass spectrometry (TOFSIMS) imaging, 3-D tomography, and high-resolution transmission electron microscopy. The TOF-SIMS imaging indicates a high concentration of sodium in the shunted areas, and 3-D tomography reveals that the sodium extends more than 2 um from the surface below shunted regions. Transmission electron microscopy investigation reveals that a stacking fault is present at an areamore » identified as shunted by DLIT imaging. After the removal of surface sodium, tomography reveals persistent sodium present around the junction depth of 300 nm and a drastic difference in sodium content at the junction when comparing shunted and nonshunted regions.« less

Activation of Ih and TTX-sensitive sodium current at subthreshold voltages during CA1 pyramidal neuron firing

PubMed Central

Yamada-Hanff, Jason

2015-01-01

We used dynamic clamp and action potential clamp techniques to explore how currents carried by tetrodotoxin-sensitive sodium channels and HCN channels (Ih) regulate the behavior of CA1 pyramidal neurons at resting and subthreshold voltages. Recording from rat CA1 pyramidal neurons in hippocampal slices, we found that the apparent input resistance and membrane time constant were strongly affected by both conductances, with Ih acting to decrease apparent input resistance and time constant and sodium current acting to increase both. We found that both Ih and sodium current were active during subthreshold summation of artificial excitatory postsynaptic potentials (EPSPs) generated by dynamic clamp, with Ih dominating at less depolarized voltages and sodium current at more depolarized voltages. Subthreshold sodium current—which amplifies EPSPs—was most effectively recruited by rapid voltage changes, while Ih—which blunts EPSPs—was maximal for slow voltage changes. The combined effect is to selectively amplify rapid EPSPs. We did similar experiments in mouse CA1 pyramidal neurons, doing voltage-clamp experiments using experimental records of action potential firing of CA1 neurons previously recorded in awake, behaving animals as command voltages to quantify flow of Ih and sodium current at subthreshold voltages. Subthreshold sodium current was larger and subthreshold Ih was smaller in mouse neurons than in rat neurons. Overall, the results show opposing effects of subthreshold sodium current and Ih in regulating subthreshold behavior of CA1 neurons, with subthreshold sodium current prominent in both rat and mouse CA1 pyramidal neurons and additional regulation by Ih in rat neurons. PMID:26289465

Vulvar pythiosis in two captive camels (Camelus dromedarius).

PubMed

Videla, Ricardo; van Amstel, Sarel; O'neill, Sarah H; Frank, Linda A; Newman, Shelley J; Vilela, Raquel; Mendoza, Leonel

2012-02-01

Two camels (Camelus dromedarius), 3- and 4-years-old, respectively, from an eastern Tennessee wildlife farm presented with persistent weight loss and large vulvar masses. An initial biopsy of the vulvar mass of one of the camels performed by a local veterinarian showed eosinophilic dermatitis. An allergic or parasitic dermatitis was suspected. The two camels were treated with one dose of sodium iodide (66 mg/kg, in 1.0 L of normosolR, IV) and ivermectin 1% (200 ug/kg PO). Upon presentation at the Veterinary Teaching Hospital, University of Tennessee, additional biopsies of the masses again revealed eosinophilic dermatitis. Microscopic examination of a Gomori methenamine silver (GMS)-stained section prepared from the biopsy of one of the camels revealed the presence of fungal-like hyphae of a mold which was suspected to be Pythium insidiosum. The vulvar masses were surgically debulked in both animals and sodium iodide and Pythium-immunotherapy prescribed. Pythium insidiosum was isolated in culture and hyphae elements were detected in histological sections confirming the diagnosis of pythiosis in both animals. Despite signs of progressive healing of the vulvar surgical areas, postoperative persistent weight lost in one of the camels suggested the possibility of gastro intestinal (GI) tract pythiosis. This camel died 5 months after the first onset of clinical signs and unfortunately a necropsy was not performed. The other camel responded well to the combination of surgery, iodides, and immunotherapy and has currently rejoined the other members of the herd.

Hematoma and abscess formation caused by Mycoplasma hominis following cesarean section

PubMed Central

Koshiba, Hisato; Koshiba, Akemi; Daimon, Yasushi; Noguchi, Toshifumi; Iwasaku, Kazuhiro; Kitawaki, Jo

2011-01-01

Mycoplasma species cannot be identified by routine bacteriological culture methods and are resistant to common antimicrobial agents. Mycoplasma hominis usually colonizes the lower urogenital tract and causes pyelonephritis, pelvic inflammatory disease, chorioamnionitis, rupture of fetal membranes, preterm labor, postpartum fever, postabortal fever, and neonatal infection. This organism is highly prevalent in cervicovaginal cultures of sexually active women. M. hominis, M. genitalis, Ureaplasma urealyticum, and U. parvum may invade and infect placental and fetal tissues, leading to adverse pregnancy outcomes. M. hominis occasionally causes nongenitourinary infection of the blood, wounds, central nervous system, joints, or respiratory tract. We present a case of a 27-year-old woman who developed abdominal wound hematoma and abscess after cesarean section. The wound was drained, but her high fever persisted, in spite of antibiotic treatment using flomoxef sodium and imipenem·cilastatin sodium. Because the exudate exhibited M. hominis growth in an anaerobic environment, we administered the quinolone ciprofloxacin. This therapy resolved her fever, and her white blood cell count and C-reactive protein level diminished to the normal ranges. To our knowledge, there are four published articles regarding the isolation of M. hominis from postcesarean incisions. Based on the current study and the literature, infection by this pathogen may cause hematoma formation with or without abscess after cesarean section or in immunosuppressed postoperative patients. In such cases, physicians may need to suspect Mycoplasma infection and initiate appropriate antibacterial treatment as soon as possible in order to avoid persistent fever. PMID:21339933

Plasma volume and renal function during and after ultramarathon running.

PubMed

Irving, R A; Noakes, T D; Burger, S C; Myburgh, K H; Querido, D; van Zyl Smit, R

1990-10-01

Plasma volume (PV) and renal function were studied in eight subjects for 3 d prior to and 6 d after a 56 km footrace. Immediately following the race, PV, creatinine clearance, and urine flow were unchanged from pre-race values. Over the subsequent 3 d, PV increased due initially to a 17 g influx of serum albumin and an associated increase in plasma sodium content, which persisted throughout the study period. A reduction in urine sodium secretion occurred during the race day. Creatinine clearance increased after the race and remained elevated for 48 h. Increases serum enzyme activities, C-reactive protein concentration, serum uric acid content, and plasma creatinine concentration and production suggest muscle damage. We suggested the following. First, the persistent post-exercise plasma volume expansion is initiated by an influx of albumin into the intravascular space with an associated increase in plasma sodium content. A decrease in urine sodium excretion during the race day would contribute to the latter. Second, the interpretation of post-race changes in serum constituents must take account of changes in plasma volume. Third, there is an increase in creatinine clearance, indicating an increase in glomerular filtration rate, after both standard and ultramarathon running. This may be caused by the products of muscle cell damage although the physiologic mechanism for this is unclear.

Role of sodium ferulate in the nociceptive sensory facilitation of neuropathic pain injury mediated by P2X(3) receptor.

PubMed

Zhang, Aixia; Xu, Changshui; Liang, Shangdong; Gao, Yun; Li, Guilin; Wei, Jie; Wan, Fang; Liu, Shuangmei; Lin, Jiari

2008-12-01

Neuropathic pain usually is persistent and no effective treatment. ATP plays an important role in the initiation of pain. P2X(3) receptors are localized in the dorsal root ganglion (DRG) neurons and activated by extracellular ATP. Sodium ferulate (SF) is an active principle from Chinese herbal medicine and has anti-inflammatory activities. This study observed the effects of SF on the nociceptive facilitation of the primary sensory afferent after chronic constriction injury (CCI) mediated by P2X(3) receptor. In this study, the content of ATP in DRG neurons was measured by high-performance liquid chromatography (HPLC). P2X(3) agonist-activated currents in DRG neurons was recorded by the whole-cell patch-clamp skill. The expression of P2X(3) mRNA in DRG neurons was analyzed by in situ hybridization. The ATP content of DRG was increased after CCI. In CCI rats treated with SF, the content of ATP in DRG neurons was reduced. SF decreased the increment of P2X(3) agonist-activated currents and P2X(3) mRNA expression in DRG neurons during CCI. SF may inhibit the initiation of pain and primary afferent sensitization mediated by P2X(3) receptor during CCI.

[Effects of phoxim and fenvalerate on TTX-S and TTX-R sodium channels in the DRG neurons of adult rat].

PubMed

Wang, X; Xiao, H; Dai, X; Liu, X; Yu, X; Wu, J

2000-05-01

To study the joint neurotoxic effects of phoxim (Pho) and fenvalerate (Fen) on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) Na(+) currents in dorsal root ganglion (DRG) neurons of adult rat. Whole cell patch clamp technique was used to test the effects of Pho and Fen on TTX-S and TTX-R sodium currents in DRG neurons. The inactivation of TTX-R sodium channel was obviously slowed down by Fen. The tau(Na) of peak currents at doses of 10, 50 and 100 micromol/L Fen and control groups were (8.10 +/- 2.41) ms, (11.78 +/- 2.76) ms, P < 0.01, (8.76 +/-1.94) ms, P < 0.05 and (6.41 +/- 1.32) ms respectively. The inactivation of TTX-R sodium channel tail currents was also significantly delayed by Fen. The tau(Na) of the tail currents at doses of 10, 50, 100 micromol/L Fen and control groups were 6.11 +/- 0.52 (P < 0.05), 7.82 +/- 0.82 (P < 0.05), 7.23 +/- 1.09 (P < 0.05) and (4.91 +/- 0.97) ms separately. As compared with TTX-R sodium channel, the TTX-S sodium channel was less responsive to Fen exposure, which only led to slowly decay TTX-S sodium tail currents. There was no any effect of Pho on the TTX-S and TTX-R sodium channels. The mixed treatment of a Pho and Fen did not show joint effect on the sodium currents. Both the peak and tail currents are changed by Fen, however, Fen has more remarkable effects on TTX-R than on TTX-S sodium channel. The combined exposure to Pho and Fen shows no joint effect on the sodium channel.

Effects of Replacement of External Sodium Chloride with Sucrose on Membrane Currents of the Squid Giant Axon

PubMed Central

Adelman, William J.; Taylor, Robert E.

1964-01-01

It was observed that a reduction of the sodium chloride concentration in the external solution bathing a squid giant axon by replacement with sucrose resulted in marked decreases in the peak inward and steady-state outward currents through the axon membrane following a step decrease in membrane potential. These effects are quantitatively acounted for by the increase in series resistance resulting from the decreased conductivity of the sea water and the assumption that the sodium current obeys a relation of the form I = k1C1 - k2C2 where C1, C2 are internal and external ion activities and k1, k2 are independent of concentration. It is concluded that the potassium ion current is independent of the sodium concentration. That the inward current is carried by sodium ions has been confirmed. The electrical potential (or barrier height) profile in the membrane which drives sodium ions appears to be independent of sodium ion concentration or current. A specific effect of the sucrose on hyperpolarizing currents was observed and noted but not investigated in detail. PMID:14232131

Irreversible modification of sodium channel inactivation in toad myelinated nerve fibres by the oxidant chloramine-T.

PubMed Central

Wang, G K

1984-01-01

The effects of externally applied chloramine-T on the excitability of single toad myelinated nerve fibres were studied. Chloramine-T is a mild oxidant which reacts specifically with the cysteine and methionine residues of proteins. Chloramine-T prolongs the action potential of a single myelinated fibre by more than 1000-fold. This effect is concentration- and time-dependent; higher concentrations and longer incubation times increase prolongation. Under voltage-clamp conditions, sodium channel inactivation is markedly inhibited by chloramine-T while sodium channel activation remains normal. Prolonged depolarization of the membrane leads to a maintained sodium current. The maintained sodium currents show activation kinetics, dependence on membrane potential, and reversal potentials which are similar to those of normal, inactivating sodium currents in untreated fibres. Both the maintained and the peak sodium currents are equally inhibited by tetrodotoxin. After partial removal of sodium inactivation by brief exposures to chloramine-T, the voltage dependence of the steady-state sodium current inactivation (h infinity) is shifted in the depolarized direction by about 20 mV, even after correction for the non-inactivating component contributed by the maintained current. The phenomena described here imply that cysteine or methionine residues are critical for the sodium channel inactivation processes. The two different modifications of inactivation, its removal shown by the maintained current, and the shift in the voltage-dependence of the remaining inactivatable channels, reveal that at least two separate residues are modified by chloramine-T. PMID:6321714

Salt taste inhibition by cathodal current.

PubMed

Hettinger, Thomas P; Frank, Marion E

2009-09-28

Effects of cathodal current, which draws cations away from the tongue and drives anions toward the tongue, depend on the ionic content of electrolytes through which the current is passed. To address the role of cations and anions in human salt tastes, cathodal currents of -40 microA to -80 microA were applied to human subjects' tongues through supra-threshold salt solutions. The salts were sodium chloride, sodium bromide, potassium chloride, ammonium chloride, calcium chloride, sodium nitrate, sodium sulfate, sodium saccharin, sodium acetate and sodium benzoate, which taken together encompass salty, bitter, sour and sweet taste qualities. The taste of NaCl, the salty and bitter tastes of the other chloride salts and the taste of NaNO(3) was inhibited, suggesting the current displaced stimulatory cations from salty and bitter receptors. However, bitter tastes of non-halide sodium salts were not inhibited, likely because other bitter receptors respond to anions. A discharge current at cathode-off ubiquitously evoked a metallic taste reminiscent of anodal taste used in clinical electrogustometry. Analogous effects on ambient NaCl responses were recorded from the hamster chorda tympani nerve. Increases in tastes of the saccharin and benzoate anions were not evoked during current flow, suggesting that cathodal current does not carry stimulatory anions to sweet receptors. Cathodal current may selectively inhibit salty and bitter-salty tastes for which proximal stimuli are cations.

Differential state-dependent modification of rat Na{sub v}1.6 sodium channels expressed in human embryonic kidney (HEK293) cells by the pyrethroid insecticides tefluthrin and deltamethrin

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Bingjun; Soderlund, David M., E-mail: dms6@cornell.edu

2011-12-15

We expressed rat Na{sub v}1.6 sodium channels in combination with the rat {beta}1 and {beta}2 auxiliary subunits in human embryonic kidney (HEK293) cells and evaluated the effects of the pyrethroid insecticides tefluthrin and deltamethrin on expressed sodium currents using the whole-cell patch clamp technique. Both pyrethroids produced concentration-dependent, resting modification of Na{sub v}1.6 channels, prolonging the kinetics of channel inactivation and deactivation to produce persistent 'late' currents during depolarization and tail currents following repolarization. Both pyrethroids also produced concentration dependent hyperpolarizing shifts in the voltage dependence of channel activation and steady-state inactivation. Maximal shifts in activation, determined from the voltagemore » dependence of the pyrethroid-induced late and tail currents, were {approx} 25 mV for tefluthrin and {approx} 20 mV for deltamethrin. The highest attainable concentrations of these compounds also caused shifts of {approx} 5-10 mV in the voltage dependence of steady-state inactivation. In addition to their effects on the voltage dependence of inactivation, both compounds caused concentration-dependent increases in the fraction of sodium current that was resistant to inactivation following strong depolarizing prepulses. We assessed the use-dependent effects of tefluthrin and deltamethrin on Na{sub v}1.6 channels by determining the effect of trains of 1 to 100 5-ms depolarizing prepulses at frequencies of 20 or 66.7 Hz on the extent of channel modification. Repetitive depolarization at either frequency increased modification by deltamethrin by {approx} 2.3-fold but had no effect on modification by tefluthrin. Tefluthrin and deltamethrin were equally potent as modifiers of Na{sub v}1.6 channels in HEK293 cells using the conditions producing maximal modification as the basis for comparison. These findings show that the actions of tefluthrin and deltamethrin of Na{sub v}1.6 channels in HEK293 cells differ from the effects of these compounds on Na{sub v}1.6 channels in Xenopus oocytes and more closely reflect the actions of pyrethroids on channels in their native neuronal environment. -- Highlights: Black-Right-Pointing-Pointer We expressed rat Na{sub v}1.6 voltage-gated sodium channels in HEK293 cells. Black-Right-Pointing-Pointer Tefluthrin and deltamethrin caused resting modification of Na{sub v}1.6 channels. Black-Right-Pointing-Pointer Only deltamethrin exhibited use-dependent enhancement of modification. Black-Right-Pointing-Pointer State-dependent effects of pyrethroids are influenced by the cellular context. Black-Right-Pointing-Pointer Channels in HEK293 cells exhibit properties similar to native neuronal channels.« less

Outcomes after Angiography with Sodium Bicarbonate and Acetylcysteine.

PubMed

Weisbord, Steven D; Gallagher, Martin; Jneid, Hani; Garcia, Santiago; Cass, Alan; Thwin, Soe-Soe; Conner, Todd A; Chertow, Glenn M; Bhatt, Deepak L; Shunk, Kendrick; Parikh, Chirag R; McFalls, Edward O; Brophy, Mary; Ferguson, Ryan; Wu, Hongsheng; Androsenko, Maria; Myles, John; Kaufman, James; Palevsky, Paul M

2018-02-15

Intravenous sodium bicarbonate and oral acetylcysteine are widely used to prevent acute kidney injury and associated adverse outcomes after angiography without definitive evidence of their efficacy. Using a 2-by-2 factorial design, we randomly assigned 5177 patients at high risk for renal complications who were scheduled for angiography to receive intravenous 1.26% sodium bicarbonate or intravenous 0.9% sodium chloride and 5 days of oral acetylcysteine or oral placebo; of these patients, 4993 were included in the modified intention-to-treat analysis. The primary end point was a composite of death, the need for dialysis, or a persistent increase of at least 50% from baseline in the serum creatinine level at 90 days. Contrast-associated acute kidney injury was a secondary end point. The sponsor stopped the trial after a prespecified interim analysis. There was no interaction between sodium bicarbonate and acetylcysteine with respect to the primary end point (P=0.33). The primary end point occurred in 110 of 2511 patients (4.4%) in the sodium bicarbonate group as compared with 116 of 2482 (4.7%) in the sodium chloride group (odds ratio, 0.93; 95% confidence interval [CI], 0.72 to 1.22; P=0.62) and in 114 of 2495 patients (4.6%) in the acetylcysteine group as compared with 112 of 2498 (4.5%) in the placebo group (odds ratio, 1.02; 95% CI, 0.78 to 1.33; P=0.88). There were no significant between-group differences in the rates of contrast-associated acute kidney injury. Among patients at high risk for renal complications who were undergoing angiography, there was no benefit of intravenous sodium bicarbonate over intravenous sodium chloride or of oral acetylcysteine over placebo for the prevention of death, need for dialysis, or persistent decline in kidney function at 90 days or for the prevention of contrast-associated acute kidney injury. (Funded by the U.S. Department of Veterans Affairs Office of Research and Development and the National Health and Medical Research Council of Australia; PRESERVE ClinicalTrials.gov number, NCT01467466 .).

[Protective effect of Uncaria rhynchophylla total alkaloids pretreatment on hippocampal neurons after acute hypoxia].

PubMed

Liu, Wei; Zhang, Zhao-qin; Zhao, Xiao-min; Gao, Yun-sheng

2006-05-01

To investigate the effect of Uncaria rhynchophylla total alkaloids (RTA) pretreatment on the voltage-gated sodium currents of the rat hippocampal neurons after acute hypoxia. Primary cultured hippocampal neurons were divided into RTA pre-treated and non-pretreated groups. Patch clamp whole-cell recording was used to compare the voltage-gated sodium current amplitude and threshold with those before hypoxia. After acute hypoxia, sodium current amplitude was significantly decreased and its threshold was upside. RTA pretreatment could inhibit the reduction of sodium current amplitude. RTA pretreatment alleviates the acute hypoxia-induced change of sodium currents, which may be one of the mechanisms for protective effect of RTA on cells.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harvey, Steven P.; Aguiar, Jeffery A.; Hacke, Peter

Here, we investigated potential-induced degradation (PID) in silicon mini-modules that were subjected to accelerated stressing to induce PID conditions. Shunted areas on the cells were identified with photoluminescence and dark lock-in thermography (DLIT) imaging. The identical shunted areas were then analyzed via time-of-flight secondary-ion mass spectrometry (TOFSIMS) imaging, 3-D tomography, and high-resolution transmission electron microscopy. The TOF-SIMS imaging indicates a high concentration of sodium in the shunted areas, and 3-D tomography reveals that the sodium extends more than 2 um from the surface below shunted regions. Transmission electron microscopy investigation reveals that a stacking fault is present at an areamore » identified as shunted by DLIT imaging. After the removal of surface sodium, tomography reveals persistent sodium present around the junction depth of 300 nm and a drastic difference in sodium content at the junction when comparing shunted and nonshunted regions.« less

Recent advances in distal tubular potassium handling

PubMed Central

Rodan, Aylin R.; Cheng, Chih-Jen

2011-01-01

It is well known that sodium reabsorption and aldosterone play important roles in potassium secretion by the aldosterone-sensitive distal nephron. Sodium- and aldosterone-independent mechanisms also exist. This review focuses on some recent studies that provide novel insights into the sodium- and aldosterone-independent potassium secretion by the aldosterone-sensitive distal nephron. In addition, we discuss a study reporting on the regulation of the mammalian potassium kidney channel ROMK by intracellular and extracellular magnesium, which may be important in the pathogenesis of persistent hypokalemia in patients with concomitant potassium and magnesium deficiency. We also discuss outstanding questions and propose working models for future investigation. PMID:21270092

A Quantitative Model for the Exchange Current of Porous Molybdenum Electrodes on Sodium Beta-Alumina in Sodium Vapor

NASA Technical Reports Server (NTRS)

Williams, R. M.; Ryan, M. A.; LeDuc, H.; Cortez, R. H.; Saipetch, C.; Shields, V.; Manatt, K.; Homer, M. L.

1998-01-01

This paper presents a model of the exchange current developed for porous molybdenum electrodes on sodium beta-alumina ceramics in low pressure sodium vapor, but which has general applicability to gas/porous metal electrodes on solid electrolytes.

mu-Opioid receptor-independent fashion of the suppression of sodium currents by mu-opioid analgesics in thalamic neurons.

PubMed

Hashimoto, Keisuke; Amano, Taku; Kasakura, Akiko; Uhl, George R; Sora, Ichiro; Sakai, Norio; Kuzumaki, Naoko; Suzuki, Tsutomu; Narita, Minoru

2009-03-27

Most reports in the literature have shown that the effects of opioid analgesics are primarily mediated by mu-opioid receptor (MOR), whereas other potential targets of opioid analgesics have not been thoroughly characterized. In this study, we found that extracellular application of morphine, fentanyl or oxycodone, which are all considered to be MOR agonists, at relatively high concentrations, but not endogenous mu-opioid peptides, produced a concentration-dependent suppression of sodium currents in cultured thalamic neurons. These effects of opioids were not affected by either a MOR antagonist naloxone or a deletion of MOR gene. Among these opioids, fentanyl strongly suppressed sodium currents to the same degree as lidocaine, and both morphine and oxycodone slightly but significantly reduced sodium currents when they were present extracellularly. In contrast, the intracellular application of morphine, but not oxycodone, fentanyl or lidocaine, reduced sodium currents. These results suggest that morphine, fentanyl and oxycodone each produce the MOR-independent suppression of sodium currents by distinct mechanisms in thalamic neurons.

Knockdown of sodium channel NaV1.6 blocks mechanical pain and abnormal bursting activity of afferent neurons in inflamed sensory ganglia

PubMed Central

Xie, Wenrui; Strong, Judith A.; Ye, Ling; Mao, Ju-Xian; Zhang, Jun-Ming

2013-01-01

Inflammatory processes in the sensory ganglia contribute to many forms of chronic pain. We previously showed that local inflammation of the lumbar sensory ganglia rapidly leads to prolonged mechanical pain behaviors and high levels of spontaneous bursting activity in myelinated cells. Abnormal spontaneous activity of sensory neurons occurs early in many preclinical pain models, and initiates many other pathological changes, but its molecular basis is not well understood. The sodium channel isoform NaV1.6 can underlie repetitive firing and excitatory persistent and resurgent currents. We used in vivo knockdown of this channel via local injection of siRNA to examine its role in chronic pain following local inflammation of the rat lumbar sensory ganglia. In normal DRG, quantitative PCR showed that cells capable of firing repetitively had significantly higher relative expression of NaV1.6. In inflamed DRG, spontaneously active bursting cells expressed high levels of NaV1.6′ immunoreactivity. In vivo knockdown of NaV1.6 locally in the lumbar DRG at the time of DRG inflammation completely blocked development of pain behaviors and abnormal spontaneous activity, while having only minor effects on unmyelinated C-cells. Current research on isoform-specific sodium channel blockers for chronic pain is largely focused on NaV1.8, because it is present primarily in unmyelinated C fiber nociceptors, or on NaV1.7, because lack of this channel causes congenital indifference to pain. However, the results suggest that NaV1.6 may be a useful therapeutic target for chronic pain, and that some pain conditions may be primarily mediated by myelinated A-fiber sensory neurons. PMID:23622763

Modulation of neuronal sodium channels by the sea anemone peptide BDS-I

PubMed Central

Liu, Pin; Jo, Sooyeon

2012-01-01

Blood-depressing substance I (BDS-I), a 43 amino-acid peptide from sea anemone venom, is used as a specific inhibitor of Kv3-family potassium channels. We found that BDS-I acts with even higher potency to modulate specific types of voltage-dependent sodium channels. In rat dorsal root ganglion (DRG) neurons, 3 μM BDS-I strongly enhanced tetrodotoxin (TTX)-sensitive sodium current but weakly inhibited TTX-resistant sodium current. In rat superior cervical ganglion (SCG) neurons, which express only TTX-sensitive sodium current, BDS-I enhanced current elicited by small depolarizations and slowed decay of currents at all voltages (EC50 ∼ 300 nM). BDS-I acted with exceptionally high potency and efficacy on cloned human Nav1.7 channels, slowing inactivation by 6-fold, with an EC50 of approximately 3 nM. BDS-I also slowed inactivation of sodium currents in N1E-115 neuroblastoma cells (mainly from Nav1.3 channels), with an EC50 ∼ 600 nM. In hippocampal CA3 pyramidal neurons (mouse) and cerebellar Purkinje neurons (mouse and rat), BDS-I had only small effects on current decay (slowing inactivation by 20–50%), suggesting relatively weak sensitivity of Nav1.1 and Nav1.6 channels. The biggest effect of BDS-I in central neurons was to enhance resurgent current in Purkinje neurons, an effect reflected in enhancement of sodium current during the repolarization phase of Purkinje neuron action potentials. Overall, these results show that BDS-I acts to modulate sodium channel gating in a manner similar to previously known neurotoxin receptor site 3 anemone toxins but with different isoform sensitivity. Most notably, BDS-I acts with very high potency on human Nav1.7 channels. PMID:22442564

Amyloid precursor protein modulates Nav1.6 sodium channel currents through a Go-coupled JNK pathway.

PubMed

Li, Shao; Wang, Xi; Ma, Quan-Hong; Yang, Wu-Lin; Zhang, Xiao-Gang; Dawe, Gavin S; Xiao, Zhi-Cheng

2016-12-23

Amyloid precursor protein (APP), commonly associated with Alzheimer's disease, also marks axonal degeneration. In the recent studies, we demonstrated that APP aggregated at nodes of Ranvier (NORs) in myelinated central nervous system (CNS) axons and interacted with Nav1.6. However, the physiological function of APP remains unknown. In this study, we described reduced sodium current densities in APP knockout hippocampal neurons. Coexpression of APP or its intracellular domains containing a VTPEER motif with Na v 1.6 sodium channels in Xenopus oocytes resulted in an increase in peak sodium currents, which was enhanced by constitutively active Go mutant and blocked by a dominant negative mutant. JNK and CDK5 inhibitor attenuated increases in Nav1.6 sodium currents induced by overexpression of APP. Nav1.6 sodium currents were increased by APPT668E (mutant Thr to Glu) and decreased by T668A (mutant Thr to ALa) mutant, respectively. The cell surface expression of Nav1.6 sodium channels in the white matter of spinal cord and the spinal conduction velocity is decreased in APP, p35 and JNK3 knockout mice. Therefore, APP modulates Nav1.6 sodium channels through a Go-coupled JNK pathway, which is dependent on phosphorylation of APP at Thr668.

Amyloid precursor protein modulates Nav1.6 sodium channel currents through a Go-coupled JNK pathway

PubMed Central

Li, Shao; Wang, Xi; Ma, Quan-Hong; Yang, Wu-lin; Zhang, Xiao-Gang; Dawe, Gavin S.; Xiao, Zhi-Cheng

2016-01-01

Amyloid precursor protein (APP), commonly associated with Alzheimer’s disease, also marks axonal degeneration. In the recent studies, we demonstrated that APP aggregated at nodes of Ranvier (NORs) in myelinated central nervous system (CNS) axons and interacted with Nav1.6. However, the physiological function of APP remains unknown. In this study, we described reduced sodium current densities in APP knockout hippocampal neurons. Coexpression of APP or its intracellular domains containing a VTPEER motif with Nav1.6 sodium channels in Xenopus oocytes resulted in an increase in peak sodium currents, which was enhanced by constitutively active Go mutant and blocked by a dominant negative mutant. JNK and CDK5 inhibitor attenuated increases in Nav1.6 sodium currents induced by overexpression of APP. Nav1.6 sodium currents were increased by APPT668E (mutant Thr to Glu) and decreased by T668A (mutant Thr to ALa) mutant, respectively. The cell surface expression of Nav1.6 sodium channels in the white matter of spinal cord and the spinal conduction velocity is decreased in APP, p35 and JNK3 knockout mice. Therefore, APP modulates Nav1.6 sodium channels through a Go-coupled JNK pathway, which is dependent on phosphorylation of APP at Thr668. PMID:28008944

Sodium intake in US ethnic subgroups and potential impact of a new sodium reduction technology: NHANES Dietary Modeling.

PubMed

Fulgoni, Victor L; Agarwal, Sanjiv; Spence, Lisa; Samuel, Priscilla

2014-12-18

Because excessive dietary sodium intake is a major contributor to hypertension, a reduction in dietary sodium has been recommended for the US population. Using the National Health and Nutrition Examination Survey (NHANES) 2007-2010 data, we estimated current sodium intake in US population ethnic subgroups and modeled the potential impact of a new sodium reduction technology on sodium intake. NHANES 2007-2010 data were analyzed using The National Cancer Institute method to estimate usual intake in population subgroups. Potential impact of SODA-LO® Salt Microspheres sodium reduction technology on sodium intake was modeled using suggested sodium reductions of 20-30% in 953 foods and assuming various market penetrations. SAS 9.2, SUDAAN 11, and NHANES survey weights were used in all calculations with assessment across age, gender and ethnic groups. Current sodium intake across all population subgroups exceeds the Dietary Guidelines 2010 recommendations and has not changed during the last decade. However, sodium intake measured as a function of food intake has decreased significantly during the last decade for all ethnicities. "Grain Products" and "Meat, Poultry, Fish, & Mixtures" contribute about 2/3rd of total sodium intake. Sodium reduction, using SODA-LO® Salt Microspheres sodium reduction technology (with 100% market penetration) was estimated to be 185-323 mg/day or 6.3-8.4% of intake depending upon age, gender and ethnic group. Current sodium intake in US ethnic subgroups exceeds the recommendations and sodium reduction technologies could potentially help reduce dietary sodium intake among those groups.

Consumer awareness of salt and sodium reduction and sodium labeling.

PubMed

Kim, M K; Lopetcharat, K; Gerard, P D; Drake, M A

2012-09-01

Reduction of dietary sodium by reduction of sodium in foods is a current industry target. Quantitative information on consumer knowledge of sodium and reduction of dietary sodium is limited. The objectives of this study were to characterize consumer knowledge and awareness of sodium and salt reduction in foods. Consumers (n = 489) participated in a quantitative internet survey designed to gather knowledge and attitudes towards dietary sodium, sodium in foods, and health. Eating habits and food consumption characteristics, knowledge of salt and sodium, and interest in health and wellness were probed. Saltiness believe and sodium knowledge indices were calculated based on correct responses to salt levels in food products. Kano analysis was conducted to determine the role of nutrition labels and satisfaction/dissatisfaction of foods. Consumers were aware of the presence of sodium in "salty" foods, and that sodium was part of salt. People who had a family history of certain diseases associated with a higher intake of dietary sodium did not necessarily have more knowledge of the relationship between sodium intake and a specific disease compared to consumers with no family history. Sodium content on the food label panel did not influence consumer dissatisfaction; however, sodium content did not necessarily increase consumer product satisfaction either. The addition of a healthy nutrient (that is, whole grain, fiber) into a current food product was appealing to consumers. For nutrient labeling, a "reduced" claim was more appealing to consumers than a "free" claim for "unhealthy" nutrients such as fat, sodium, and sugar. This study demonstrated the current state of consumer knowledge on sodium and salt reduction, and consumer perception of the relationship between diets high in sodium and many chronic diseases. Information that may contribute to consumer satisfaction on nutrition panel labeling was also determined. © 2012 Institute of Food Technologists®

Sodium influxes in internally perfused squid giant axon during voltage clamp.

PubMed

Atwater, I; Bezanilla, F; Rojas, E

1969-05-01

1. An experimental method for measuring ionic influxes during voltage clamp in the giant axon of Dosidicus is described; the technique combines intracellular perfusion with a method for controlling membrane potential.2. Sodium influx determinations were carried out while applying rectangular pulses of membrane depolarization. The ratio ;measured sodium influx/computed ionic flux during the early current' is 0.92 +/- 0.12.3. Plots of measured sodium influx and computed ionic flux during the early current against membrane potential are very similar. There was evidence that the membrane potential at which the sodium influx vanishes is the potential at which the early current reverses.

Molecular and functional differences in voltage-activated sodium currents between GABA projection neurons and dopamine neurons in the substantia nigra

PubMed Central

Ding, Shengyuan; Wei, Wei

2011-01-01

GABA projection neurons (GABA neurons) in the substantia nigra pars reticulata (SNr) and dopamine projection neurons (DA neurons) in substantia nigra pars compacta (SNc) have strikingly different firing properties. SNc DA neurons fire low-frequency, long-duration spikes, whereas SNr GABA neurons fire high-frequency, short-duration spikes. Since voltage-activated sodium (NaV) channels are critical to spike generation, the different firing properties raise the possibility that, compared with DA neurons, NaV channels in SNr GABA neurons have higher density, faster kinetics, and less cumulative inactivation. Our quantitative RT-PCR analysis on immunohistochemically identified nigral neurons indicated that mRNAs for pore-forming NaV1.1 and NaV1.6 subunits and regulatory NaVβ1 and Navβ4 subunits are more abundant in SNr GABA neurons than SNc DA neurons. These α-subunits and β-subunits are key subunits for forming NaV channels conducting the transient NaV current (INaT), persistent Na current (INaP), and resurgent Na current (INaR). Nucleated patch-clamp recordings showed that INaT had a higher density, a steeper voltage-dependent activation, and a faster deactivation in SNr GABA neurons than in SNc DA neurons. INaT also recovered more quickly from inactivation and had less cumulative inactivation in SNr GABA neurons than in SNc DA neurons. Furthermore, compared with nigral DA neurons, SNr GABA neurons had a larger INaR and INaP. Blockade of INaP induced a larger hyperpolarization in SNr GABA neurons than in SNc DA neurons. Taken together, these results indicate that NaV channels expressed in fast-spiking SNr GABA neurons and slow-spiking SNc DA neurons are tailored to support their different spiking capabilities. PMID:21880943

Active ion transport in dog tongue: a possible role in taste.

PubMed

DeSimone, J A; Heck, G L; DeSimone, S K

1981-11-27

An in vitro preparation of the dorsal epithelium of the dog tongue actively transports ions, producing a transepithelial potential difference characteristic of the ions and their concentration. Hypertonic sodium chloride solutions generally cause increased potentials and short-circuit currents and reduced resistances when placed on the mucosal surface. This hypertonic flux is eliminated by ouabain and is not found in ventral lingual epithelia. When either sodium acetate or tetramethylammonium chloride is substituted for sodium chloride in the mucosal medium, the currents are diminished but their sum at a given concentration approximates that for sodium chloride at the same concentration. This result suggests a current composed of inward sodium ion movement and outward chloride ion movement. Actively regulated potentials and currents, whether generated in the taste buds or in supporting cells, may be important in both normal chemotransduction and in taste responses evoked by currents passing through the tongue.

Sodium intake status in United States and potential reduction modeling: an NHANES 2007-2010 analysis.

PubMed

Agarwal, Sanjiv; Fulgoni, Victor L; Spence, Lisa; Samuel, Priscilla

2015-11-01

Limiting dietary sodium intake has been a consistent dietary recommendation. Using NHANES 2007-2010 data, we estimated current sodium intake and modeled the potential impact of a new sodium reduction technology on sodium intake. NHANES 2007-2010 data were used to assess current sodium intake. The National Cancer Institute method was used for usual intake determination. Suggested sodium reductions using SODA-LO (®) Salt Microspheres ranged from 20% to 30% in 953 foods and usual intakes were modeled by using various reduction factors and levels of market penetration. SAS 9.2, SUDAAN 11, and NHANES survey weights were used in all calculations with assessment across gender and age groups. Current (2007-2010) sodium intake (mg/day) exceeds recommendations across all age gender groups and has not changed during the last decade. However, sodium intake measured as a function of food intake (mg/g food) has decreased significantly during the last decade. Two food categories contribute about 2/3rd of total sodium intake: "Grain Products" and "Meat, Poultry, Fish & Mixtures". Sodium reduction, with 100% market penetration of the new technology, was estimated to be 230-300 mg/day or 7-9% of intake depending upon age and gender group. Sodium reduction innovations like SODA-LO (®) Salt Microspheres could contribute to meaningful reductions in sodium intake.

Effect of phenytoin on sodium conductances in rat hippocampal CA1 pyramidal neurons

PubMed Central

Zeng, Zhen; Hill-Yardin, Elisa L.; Williams, David; O'Brien, Terence; Serelis, Andris

2016-01-01

The antiepileptic drug phenytoin (PHT) is thought to reduce the excitability of neural tissue by stabilizing sodium channels (NaV) in inactivated states. It has been suggested the fast-inactivated state (IF) is the main target, although slow inactivation (IS) has also been implicated. Other studies on local anesthetics with similar effects on sodium channels have implicated the NaV voltage sensor interactions. In this study, we reexamined the effect of PHT in both equilibrium and dynamic transitions between fast and slower forms of inactivation in rat hippocampal CA1 pyramidal neurons. The effects of PHT were observed on fast and slow inactivation processes, as well as on another identified “intermediate” inactivation process. The effect of enzymatic removal of IF was also studied, as well as effects on the residual persistent sodium current (INaP). A computational model based on a gating charge interaction was derived that reproduced a range of PHT effects on NaV equilibrium and state transitions. No effect of PHT on IF was observed; rather, PHT appeared to facilitate the occupancy of other closed states, either through enhancement of slow inactivation or through formation of analogous drug-bound states. The overall significance of these observations is that our data are inconsistent with the commonly held view that the archetypal NaV channel inhibitor PHT stabilizes fast inactivation states, and we demonstrate that conventional slow activation “IS” and the more recently identified intermediate-duration inactivation process “II” are the primary functional targets of PHT. In addition, we show that the traditional explanatory frameworks based on the “modulated receptor hypothesis” can be substituted by simple, physiologically plausible interactions with voltage sensors. Additionally, INaP was not preferentially inhibited compared with peak INa at short latencies (50 ms) by PHT. PMID:27489371

Molecular Basis of Paralytic Neurotoxin Action on Voltage-Sensitive Sodium Channels

DTIC Science & Technology

1987-10-20

reaching a new steady state rate of inactivation after 5 min. Fig. 6C shows a family of sodium currents elicited by depolarizations to test potentials...Fig. 7 compares time courses of decay of sodium currents during test pulses to +10 mV for 70 msec in the presence or absence of I x 10-7 CsTx on semi...logarithmic coordinates. The decay of the sodium currents in the absence of toxin was described by a single exponential with a decay constant of 0.7

Channelopathies from Mutations in the Cardiac Sodium Channel Protein Complex

PubMed Central

Adsit, Graham S.; Vaidyanathan, Ravi; Galler, Carla M.; Kyle, John W.; Makielski, Jonathan C.

2013-01-01

The cardiac sodium current underlies excitability in heart, and inherited abnormalities of the proteins regulating and conducting this current cause inherited arrhythmia syndromes. This review focuses on inherited mutations in non-pore forming proteins of sodium channel complexes that cause cardiac arrhythmia, and the deduced mechanisms by which they affect function and dysfunction of the cardiac sodium current. Defining the structure and function of these complexes and how they are regulated will contribute to understanding the possible roles for this complex in normal and abnormal physiology and homeostasis. PMID:23557754

Tetrodotoxin-sensitive, voltage-dependent sodium currents in hair cells from the alligator cochlea.

PubMed

Evans, M G; Fuchs, P A

1987-10-01

We have used whole-cell patch clamp techniques to record from tall hair cells isolated from the apical half of the alligator cochlea. Some of these cells gave action potentials in response to depolarizing current injections. When the same cells were voltage clamped, large transient inward currents followed by smaller outward currents were seen in response to depolarizing steps. We studied the transient inward current after the outward current had been blocked by external tetraethylammonium (20 mM) or by replacing internal potassium with cesium. It was found to be a sodium current because it was abolished by either replacing external sodium with choline or by external application of tetrodotoxin (100 nM). The sodium current showed voltage-dependent activation and inactivation. Most of the spiking hair cells came from the apex of the cochlea, where they would be subject to low-frequency mechanical stimulation in vivo.

Sodium influxes in internally perfused squid giant axon during voltage clamp

PubMed Central

Atwater, I.; Bezanilla, F.; Rojas, E.

1969-01-01

1. An experimental method for measuring ionic influxes during voltage clamp in the giant axon of Dosidicus is described; the technique combines intracellular perfusion with a method for controlling membrane potential. 2. Sodium influx determinations were carried out while applying rectangular pulses of membrane depolarization. The ratio `measured sodium influx/computed ionic flux during the early current' is 0·92 ± 0·12. 3. Plots of measured sodium influx and computed ionic flux during the early current against membrane potential are very similar. There was evidence that the membrane potential at which the sodium influx vanishes is the potential at which the early current reverses. PMID:5767887

Effect of thiopental sodium on N-methyl-D-aspartate-gated currents.

PubMed

Liu, Hongliang; Dai, Tijun; Yao, Shanglong

2006-05-01

N-methyl-D-aspartate (NMDA) receptors in the prefrontal cortex (PFC) are closely related with the excitability of pyramidal neurons and PFC function. As the effect of thiopental sodium on the central nervous system may partly result from the inhibition of PFC NMDA receptors, we investigated the effect of thiopental sodium with different concentrations on NMDA-gated currents in acutely dissociated rat PFC pyramidal neurons. We sought to determine whether thiopental sodium inhibits NMDA receptor function. Three to four week old male Sprague-Dawley rats were sacrificed and the PFC was dissected. Pyramidal neurons from the PFC were prepared and standard whole-cell patch clamp recordings were performed. Escalating concentrations from 3-1000 microM NMDA were applied 100 microm from the pyramidal cells, and the concentration in the effect compartment related to 50% effect (EC50) of NMDA was determined for the ensuing experiments. One hundred microM NMDA alone (control) or NMDA with different concentrations (10-1000 microM) of thiopental sodium were applied. After the inhibitory concentration, in 50% of NMDA effect (IC50) of thiopental sodium was established this IC50 and NMDA 3-1000 microM were applied 100 microm from the pyramidal cells. The EC50 value of NMDA under the effect of IC50 thiopental sodium was determined. N-methyl-D-aspartate induced inward currents in a concentration-dependent manner, which were completely antagonized by 50 microM AP5. The maximal amplitude of NMDA-induced current was 1.15 +/- 0.27 nA. The EC50 of NMDA was 53.6 +/- 12.4 microM. The NMDA (100 microM)-gated current was inhibited by thiopental sodium in a concentration-dependent manner, and the IC50 of thiopental sodium was 33.6 +/- 6.1 microM. Under the effect of 33.6 microM thiopental sodium, the maximal amplitude of NMDA-induced current was 0.87 +/- 0.17 nA. The concentration-response curve of NMDA was shifted rightwards. The EC50 of NMDA was 128 +/- 15 microM, which was greater than that of NMDA without thiopental sodium (P < 0.01). Thiopental sodium decreases NMDA-gated currents in acutely dissociated rat prefrontal cortical pyramidal neurons in a concentration-dependent manner.

Unilateral eyelid angioedema with congestion of the right bulbar conjunctiva due to loxoprofen sodium.

PubMed

Tsuruta, Daisuke; Oshimo, Tomoko; Sowa, Junko; Ishii, Masamitsu; Kobayashi, Hiromi

2011-01-01

Angioedema is a variant of urticaria that causes deep dermal and subcutaneous swelling. It frequently is a unilateral reaction and usually lasts for several hours but may persist for several days. We report 2 cases of angioedema that involved the right upper and lower eyelids and was associated with congestion of the right bulbar conjunctiva; the symptoms started approximately 1 to 2 hours after taking loxoprofen sodium. All of the symptoms subsided after oral corticosteroid therapy. In both cases, an oral challenge test with 60 mg of loxoprofen sodium (contained in a tablet) caused swelling of the right upper eyelid within several hours, followed by swelling of the right bulbar conjunctiva. We believe the drug reaction in both patients is angioedema.

Electrochemical oxidation of tramadol in low-salinity reverse osmosis concentrates using boron-doped diamond anodes.

PubMed

Lütke Eversloh, Christian; Schulz, Manoj; Wagner, Manfred; Ternes, Thomas A

2015-04-01

The electrochemical treatment of low-salinity reverse osmosis (RO) concentrates was investigated using tramadol (100 μM) as a model substance for persistent organic contaminants. Galvanostatic degradation experiments using boron-doped diamond electrodes at different applied currents were conducted in RO concentrates as well as in ultra-pure water containing either sodium chloride or sodium sulfate. Kinetic investigations revealed a significant influence of in-situ generated active chlorine besides direct anodic oxidation. Therefore, tramadol concentrations decreased more rapidly at elevated chloride content. Nevertheless, reduction of total organic carbon (TOC) was found to be comparatively low, demonstrating that transformation rather than mineralization was taking place. Early stage product formation could be attributed to both direct and indirect processes, including demethylation, hydroxylation, dehydration, oxidative aromatic ring cleavage and halogenation reactions. The latter led to various halogenated derivatives and resulted in AOX (adsorbable organic halogens) formation in the lower mg/L-range depending on the treatment conditions. Characterisation of transformation products (TPs) was achieved via MS(n) experiments and additional NMR measurements. Based on identification and quantification of the main TPs in different matrices and on additional potentiostatic electrolysis, a transformation pathway was proposed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Explaining pathological changes in axonal excitability through dynamical analysis of conductance-based models

NASA Astrophysics Data System (ADS)

Coggan, Jay S.; Ocker, Gabriel K.; Sejnowski, Terrence J.; Prescott, Steven A.

2011-10-01

Neurons rely on action potentials, or spikes, to relay information. Pathological changes in spike generation likely contribute to certain enigmatic features of neurological disease, like paroxysmal attacks of pain and muscle spasm. Paroxysmal symptoms are characterized by abrupt onset and short duration, and are associated with abnormal spiking although the exact pathophysiology remains unclear. To help decipher the biophysical basis for 'paroxysmal' spiking, we replicated afterdischarge (i.e. continued spiking after a brief stimulus) in a minimal conductance-based axon model. We then applied nonlinear dynamical analysis to explain the dynamical basis for initiation and termination of afterdischarge. A perturbation could abruptly switch the system between two (quasi-)stable attractor states: rest and repetitive spiking. This bistability was a consequence of slow positive feedback mediated by persistent inward current. Initiation of afterdischarge was explained by activation of the persistent inward current forcing the system to cross a saddle point that separates the basins of attraction associated with each attractor. Termination of afterdischarge was explained by the attractor associated with repetitive spiking being destroyed. This occurred when ultra-slow negative feedback, such as intracellular sodium accumulation, caused the saddle point and stable limit cycle to collide; in that regard, the active attractor is not truly stable when the slowest dynamics are taken into account. The model also explains other features of paroxysmal symptoms, including temporal summation and refractoriness.

Nephrolithiasis and osteoporosis associated with hypophosphatemia caused by mutations in the type 2a sodium-phosphate cotransporter.

PubMed

Prié, Dominique; Huart, Virginie; Bakouh, Naziha; Planelles, Gabrielle; Dellis, Olivier; Gérard, Bénédicte; Hulin, Philippe; Benqué-Blanchet, François; Silve, Caroline; Grandchamp, Bernard; Friedlander, Gérard

2002-09-26

Epidemiologic studies suggest that genetic factors confer a predisposition to the formation of renal calcium stones or bone demineralization. Low serum phosphate concentrations due to a decrease in renal phosphate reabsorption have been reported in some patients with these conditions, suggesting that genetic factors leading to a decrease in renal phosphate reabsorption may contribute to them. We hypothesized that mutations in the gene coding for the main renal sodium-phosphate cotransporter (NPT2a) may be present in patients with these disorders. We studied 20 patients with urolithiasis or bone demineralization and persistent idiopathic hypophosphatemia associated with a decrease in maximal renal phosphate reabsorption. The coding region of the gene for NPT2a was sequenced in all patients. The functional consequences of the mutations identified were analyzed by expressing the mutated RNA in Xenopus laevis oocytes. Two patients, one with recurrent urolithiasis and one with bone demineralization, were heterozygous for two distinct mutations. One mutation resulted in the substitution of phenylalanine for alanine at position 48, and the other in a substitution of methionine for valine at position 147. Phosphate-induced current and sodium-dependent phosphate uptake were impaired in oocytes expressing the mutant NPT2a. Coinjection of oocytes with wild-type and mutant RNA indicated that the mutant protein had altered function. Heterozygous mutations in the NPT2a gene may be responsible for hypophosphatemia and urinary phosphate loss in persons with urolithiasis or bone demineralization. Copyright 2002 Massachusetts Medical Society

Human induced pluripotent stem cell-derived hepatic cell lines as a new model for host interaction with hepatitis B virus

PubMed Central

Kaneko, Shun; Kakinuma, Sei; Asahina, Yasuhiro; Kamiya, Akihide; Miyoshi, Masato; Tsunoda, Tomoyuki; Nitta, Sayuri; Asano, Yu; Nagata, Hiroko; Otani, Satoshi; Kawai-Kitahata, Fukiko; Murakawa, Miyako; Itsui, Yasuhiro; Nakagawa, Mina; Azuma, Seishin; Nakauchi, Hiromitsu; Nishitsuji, Hironori; Ujino, Saneyuki; Shimotohno, Kunitada; Iwamoto, Masashi; Watashi, Koichi; Wakita, Takaji; Watanabe, Mamoru

2016-01-01

Hepatitis B virus (HBV) is not eradicated by current antiviral therapies due to persistence of HBV covalently closed circular DNA (cccDNA) in host cells, and thus development of novel culture models for productive HBV infection is urgently needed, which will allow the study of HBV cccDNA eradication. To meet this need, we developed culture models of HBV infection using human induced pluripotent stem cell-derived hepatocyte lineages, including immature proliferating hepatic progenitor-like cell lines (iPS-HPCs) and differentiated hepatocyte-like cells (iPS-Heps). These cells were susceptible to HBV infection, produced HBV particles, and maintained innate immune responses. The infection efficiency of HBV in iPS-HPCs predominantly depended on the expression levels of sodium taurocholate cotransporting polypeptide (NTCP), and was low relative to iPS-Heps: however, long-term culture of iPS-Heps was difficult. To provide a model for HBV persistence, iPS-HPCs overexpressing NTCP were established. The long-term persistence of HBV cccDNA was detected in iPS-HPCs overexpressing NTCP, and depended on the inhibition of the Janus-kinase signaling pathway. In conclusion, this study provides evidence that iPS-derived hepatic cell lines can be utilized for novel HBV culture models with genetic variation to investigate the interactions between HBV and host cells and the development of anti-HBV strategies. PMID:27386799

Behavioral responses and fluid regulation in male rats after combined dietary sodium deficiency and water deprivation.

PubMed

Lucia, Kimberly J; Curtis, Kathleen S

2018-02-01

Most investigators use a single treatment such as water deprivation or dietary sodium deficiency to evaluate thirst or sodium appetite, which underlie behavioral responses to body fluid challenges. The goal of the present experiments was to assess the effects of combined treatments in driving behaviors. Therefore, we evaluated the effect of combined overnight water deprivation and dietary sodium deficiency on water intake and salt intake by adult male rats in 2-bottle (0.5M NaCl and water) tests. Overnight water deprivation alone increased water intake, and 10days of dietary sodium deficiency increased 0.5M NaCl intake, with a secondary increase in water intake. During combined water deprivation and dietary sodium deficiency, water intake was enhanced and 0.5M NaCl was reduced, but not eliminated, suggesting that physiologically relevant behavioral responses persist. Nonetheless, the pattern of fluid intake was altered by the combined treatments. We also assessed the effect of these behaviors on induced deficits in body sodium and fluid volume during combined treatments and found that, regardless of treatment, fluid ingestion partially repleted the induced deficits. Finally, we examined urine volume and sodium excretion during dietary sodium deficiency with or without overnight water deprivation and found that, whether or not rats were water deprived, and regardless of water consumption, sodium excretion was minimal. Thus, the combination of water deprivation and dietary sodium deficiency appears to arouse drives that stimulate compensatory behavioral responses. These behaviors, in conjunction with physiological adaptations to the treatments, underlie body sodium and volume repletion in the face of combined water deprivation and dietary sodium deficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

Relation of Dietary Sodium (Salt) to Blood Pressure and Its Possible Modulation by Other Dietary Factors: The INTERMAP Study.

PubMed

Stamler, Jeremiah; Chan, Queenie; Daviglus, Martha L; Dyer, Alan R; Van Horn, Linda; Garside, Daniel B; Miura, Katsuyuki; Wu, Yangfeng; Ueshima, Hirotsugu; Zhao, Liancheng; Elliott, Paul

2018-04-01

Available data indicate that dietary sodium (as salt) relates directly to blood pressure (BP). Most of these findings are from studies lacking dietary data; hence, it is unclear whether this sodium-BP relationship is modulated by other dietary factors. With control for multiple nondietary factors, but not body mass index, there were direct relations to BP of 24-hour urinary sodium excretion and the urinary sodium/potassium ratio among 4680 men and women 40 to 59 years of age (17 population samples in China, Japan, United Kingdom, and United States) in the INTERMAP (International Study on Macro/Micronutrients and Blood Pressure), and among its 2195 American participants, for example, 2 SD higher 24-hour urinary sodium excretion (118.7 mmol) associated with systolic BP 3.7 mm Hg higher. These sodium-BP relations persisted with control for 13 macronutrients, 12 vitamins, 7 minerals, and 18 amino acids, for both sex, older and younger, blacks, Hispanics, whites, and socioeconomic strata. With control for body mass index, sodium-BP-but not sodium/potassium-BP-relations were attenuated. Normal weight and obese participants manifested significant positive relations to BP of urinary sodium; relations were weaker for overweight people. At lower but not higher levels of 24-hour sodium excretion, potassium intake blunted the sodium-BP relation. The adverse association of dietary sodium with BP is minimally attenuated by other dietary constituents; these findings underscore the importance of reducing salt intake for the prevention and control of prehypertension and hypertension. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00005271. © 2018 American Heart Association, Inc.

Electrochemical Dissolution of Tungsten Carbide in NaCl-KCl-Na2WO4 Molten Salt

NASA Astrophysics Data System (ADS)

Zhang, Liwen; Nie, Zuoren; Xi, Xiaoli; Ma, Liwen; Xiao, Xiangjun; Li, Ming

2018-02-01

Tungsten carbide was utilized as anode to extract tungsten in a NaCl-KCl-Na2WO4 molten salt, and the electrochemical dissolution was investigated. Although the molten salt electrochemical method is a short process method of tungsten extraction from tungsten carbide in one step, the dissolution efficiency and current efficiency are quite low. In order to improve the dissolution rate and current efficiency, the sodium tungstate was added as the active substance. The dissolution rate, the anode current efficiency, and the cathode current efficiency were calculated with different contents of sodium tungstate addition. The anodes prior to and following the reaction, as well as the product, were analyzed through X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometry. The results demonstrated that the sodium tungstate could improve the dissolution rate and the current efficiency, due to the addition of sodium tungstate decreasing the charge transfer resistance in the electrolysis system. Due to the fact that the addition of sodium tungstate could remove the carbon during electrolysis, pure tungsten powders with 100 nm diameter were obtained when the content of sodium tungstate was 1.0 pct.

Survival of spumavirus, a primate retrovirus, in laboratory media and water.

PubMed

Lotlikar, Madhavi S; Lipson, Steven M

2002-06-04

The persistence of a previously characterized spumavirus strain (strain SV-522) was investigated utilizing various laboratory media and waters, including Eagle's minimal essential medium (EMEM) plus 0% fetal bovine serum (EMEM-0%), EMEM-2%, EMEM-10%, Chlamydia transport medium (CTM), phosphate-buffered saline, distilled, estuarine, and marine water, human serum, and the germicides, ethyl alcohol (70%) and sodium hypochlorite (10%). Experiments were performed at 4 degrees C and/or 23 degrees C. Infectivity endpoints were determined in stock aliquots upon initiation of testing and then after 3, 5, 7, and 10 days. The virus was reisolated from all diluents after 5 days at 23 degrees C and in EMEM-10% after 7 days. The virus was detected in CTM, EMEM-2%, EMEM-10%, and estuarine and marine waters after 7 days at 4 degrees C. Differences in the persistence of the virus may be ascribed to temperature and organic load. Water ionic strengths (e.g., estuarine vs. marine water) had no effect on modifying persistence of viral particles. Infectivity of spumavirus was undetectable after 30 s in 70% ethanol or 10% sodium hypochlorite. After 30 min at 23 degrees C, spumavirus infectivity in normal but not heat-inactivated human serum increased by almost 100-fold. Persistence of infectivity of primate spumavirus after 7 days in media and waters, and the agent's infectious potential in the human host, emphasize a need for cautious recognition during the manipulation of primate cells/organs and in the handling of primates themselves.

Substance P modulation of TRPC3/7 channels improves respiratory rhythm regularity and ICAN-dependent pacemaker activity.

PubMed

Ben-Mabrouk, Faiza; Tryba, Andrew K

2010-04-01

Neuromodulators, such as substance P (SubP), play an important role in modulating many rhythmic activities driven by central pattern generators (e.g. locomotion, respiration). However, the mechanism by which SubP enhances breathing regularity has not been determined. Here, we used mouse brainstem slices containing the pre-Bötzinger complex to demonstrate, for the first time, that SubP activates transient receptor protein canonical (TRPC) channels to enhance respiratory rhythm regularity. Moreover, SubP enhancement of network regularity is accomplished via selective enhancement of ICAN (inward non-specific cation current)-dependent intrinsic bursting properties. In contrast to INaP (persistent sodium current)-dependent pacemakers, ICAN-dependent pacemaker bursting activity is TRPC-dependent. Western Blots reveal TRPC3 and TRPC7 channels are expressed in rhythmically active ventral respiratory group island preparations. Taken together, these data suggest that SubP-mediated activation of TRPC3/7 channels underlies rhythmic ICAN-dependent pacemaker activity and enhances the regularity of respiratory rhythm activity.

Uptake and Accumulation of Pharmaceuticals in Overhead- and Surface-Irrigated Greenhouse Lettuce.

PubMed

Bhalsod, Gemini D; Chuang, Ya-Hui; Jeon, Sangho; Gui, Wenjun; Li, Hui; Ryser, Elliot T; Guber, Andrey K; Zhang, Wei

2018-01-31

Understanding the uptake and accumulation of pharmaceuticals in vegetables under typical irrigation practices is critical to risk assessment of crop irrigation with reclaimed water. This study investigated the pharmaceutical residues in greenhouse lettuce under overhead and soil-surface irrigations using pharmaceutical-contaminated water. Compared to soil-surface irrigation, overhead irrigation substantially increased the pharmaceutical residues in lettuce shoots. The increased residue levels persisted even after washing for trimethoprim, monensin sodium, and tylosin, indicating their strong sorption to the shoots. The postwashing concentrations in fresh shoots varied from 0.05 ± 0.04 μg/kg for sulfadiazine to 345 ± 139 μg/kg for carbamazepine. Root concentration factors ranged from 0.04 ± 0.14 for tylosin to 19.2 ± 15.7 for sulfamethoxazole. Translocation factors in surface-irrigated lettuce were low for sulfamethoxalzole, trimethoprim, monensin sodium, and tylosin (0.07-0.15), but high for caffeine (4.28 ± 3.01) and carbamazepine (8.15 ± 2.87). Carbamazepine was persistent in soil and hyperaccumulated in shoots.

Sodium effect on self-organization of amphiphilic carboxylates: formation of structured micelles and superlattices.

PubMed

Rosenlehner, Karin; Schade, Boris; Böttcher, Christoph; Jäger, Christof M; Clark, Timothy; Heinemann, Frank W; Hirsch, Andreas

2010-08-16

Not only the self-aggregation of dendritic polycarboxylates into structurally persistent micelles, but also that of the micelles themselves into superlattices is controlled by alkali-metal counterions and shows a pronounced sodium effect. Our combined experimental and computational work has revealed the formation of superlattices for the first time. The behavior of a variety of amphiphilic carboxylates and the different effects of the alkali cations Li(+), Na(+), and K(+) have been investigated by conductivity measurements, cryogenic transmission electron microscopy (cryo-TEM), and molecular-dynamics (MD) simulations. Together, these show that sodium salts of the amphiphiles give the most stable micelles, followed by lithium and potassium. Our results suggest that ion multiplets in bridging positions, rather than contact ion pairs, are responsible for the enhanced stability and the formation of hexagonally ordered superlattices with sodium counterions. Potassium ions do not form such ion multiplets and cannot therefore induce aggregation of the micelles. This sodium effect has far-reaching consequences for a large number of biological and technical systems and sheds new light on the origin of specific-ion effects.

Habitual dietary sodium intake is inversely associated with coronary flow reserve in middle-aged male twins.

PubMed

Eufinger, Silvia C; Votaw, John; Faber, Tracy; Ziegler, Thomas R; Goldberg, Jack; Bremner, J Douglas; Vaccarino, Viola

2012-03-01

Evidence links dietary sodium to hypertension and cardiovascular disease (CVD), but investigation of its influence on cardiovascular function is limited. We examined the relation between habitual dietary sodium and coronary flow reserve (CFR), which is a measure of overall coronary vasodilator capacity and microvascular function. We hypothesized that increased sodium consumption is associated with lower CFR. Habitual daily sodium intake for the previous 12 mo was measured in 286 male middle-aged twins (133 monozygotic and dizygotic pairs and 20 unpaired twins) by using the Willett food-frequency questionnaire. CFR was measured by positron emission tomography [N(13)]-ammonia, with quantitation of myocardial blood flow at rest and after adenosine stress. Mixed-effects regression analysis was used to assess the association between dietary sodium and CFR. An increase in dietary sodium of 1000 mg/d was associated with a 10.0% lower CFR (95% CI: -17.0%, -2.5%) after adjustment for demographic, lifestyle, nutritional, and CVD risk factors (P = 0.01). Across quintiles of sodium consumption, dietary sodium was inversely associated with CFR (P-trend = 0.03), with the top quintile (>1456 mg/d) having a 20% lower CFR than the bottom quintile (<732 mg /d). This association also persisted within pairs: a 1000-mg/d difference in dietary sodium between brothers was associated with a 10.3% difference in CFR after adjustment for potential confounders (P = 0.02). Habitual dietary sodium is inversely associated with CFR independent of CVD risk factors and shared familial and genetic factors. Our study suggests a potential novel mechanism for the adverse effects of dietary sodium on the cardiovascular system. This trial was registered at clinicaltrials.gov as NCT00017836.

Habitual dietary sodium intake is inversely associated with coronary flow reserve in middle-aged male twins1234

PubMed Central

Eufinger, Silvia C; Votaw, John; Faber, Tracy; Ziegler, Thomas R; Goldberg, Jack; Bremner, J Douglas

2012-01-01

Background: Evidence links dietary sodium to hypertension and cardiovascular disease (CVD), but investigation of its influence on cardiovascular function is limited. Objective: We examined the relation between habitual dietary sodium and coronary flow reserve (CFR), which is a measure of overall coronary vasodilator capacity and microvascular function. We hypothesized that increased sodium consumption is associated with lower CFR. Design: Habitual daily sodium intake for the previous 12 mo was measured in 286 male middle-aged twins (133 monozygotic and dizygotic pairs and 20 unpaired twins) by using the Willett food-frequency questionnaire. CFR was measured by positron emission tomography [N13]-ammonia, with quantitation of myocardial blood flow at rest and after adenosine stress. Mixed-effects regression analysis was used to assess the association between dietary sodium and CFR. Results: An increase in dietary sodium of 1000 mg/d was associated with a 10.0% lower CFR (95% CI: −17.0%, −2.5%) after adjustment for demographic, lifestyle, nutritional, and CVD risk factors (P = 0.01). Across quintiles of sodium consumption, dietary sodium was inversely associated with CFR (P-trend = 0.03), with the top quintile (>1456 mg/d) having a 20% lower CFR than the bottom quintile (<732 mg /d). This association also persisted within pairs: a 1000-mg/d difference in dietary sodium between brothers was associated with a 10.3% difference in CFR after adjustment for potential confounders (P = 0.02). Conclusions: Habitual dietary sodium is inversely associated with CFR independent of CVD risk factors and shared familial and genetic factors. Our study suggests a potential novel mechanism for the adverse effects of dietary sodium on the cardiovascular system. This trial was registered at clinicaltrials.gov as NCT00017836. PMID:22258268

Consumer awareness and interest toward sodium reduction trends in Korea.

PubMed

Kim, Mina K; Lee, Kwang-Geun

2014-07-01

Reduction of dietary sodium intake by lowering amount of sodium in foods is a global industry target. Quantitative information on current consumer knowledge of sodium reduction trends in Korea is unknown. The objective of this study was to quantify the consumer knowledge and awareness of sodium and salt reduction in foods and to characterize consumer interest in health labeling on the food package. Additionally, comparison of consumer knowledge status between Korea and United States was followed. Consumers (n = 289) participated in an internet survey designed to gauge consumer knowledge and attitudes toward dietary sodium, the sodium content in representative food products (n = 27), and their interest toward specific health claims, including sodium labeling. Questions regarding demographics as well as consumption characteristics were asked. Sodium knowledge index and saltiness belief index were calculated based on the number of correct responses regarding the salt level and sodium content in given food products. Kano analysis was conducted to determine the role of nutrition labels in consumer satisfaction with products. Current consumer knowledge on the sodium content in food products was high, and consumers were adept at matching the sodium content with the salty taste intensity of food products. Consumers' knowledge of the relationship between diets high in sodium and an increased risk of developing previously reported sodium-related diseases, such as hypertension, coronary heart disease, kidney disease, and stomach cancer, were also high. Information on the nutrition panel that influences the consumer satisfaction (trans-fat, sodium, ingredient list, and country of origin) as well as adjective-nutrition claim pairs that appeal positively to purchase intent of the product were identified. This work provided the current status of Korean consumer knowledge on the amount of sodium in food and that sodium can be a risk factor of developing chronic diseases. It also provided practical information to food marketers on what consumers like and what they want to see on product labels in Korea. © 2014 Institute of Food Technologists®

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bean, Bruce Palmer

The effects of ether and halothane on membrane currents in the voltage clamped crayfish giant axon membrane were investigated. Concentrations of ether up to 300 mM and of halothane up to 32 mM had no effect on resting potential or leakage conductance. Ether and halothane reduced the size of sodium currents without changing the voltage dependence of the peak currents or their reversal potential. Ether and halothane also produced a reversible, dose-dependent speeding of sodium current decay at all membrane potentials. Ether reduced the time constants for inactivation, and also shifted the midpoint of the steady-state inactivation curve in themore » hyperpolarizing direction. Potassium currents were smaller with ether present, with no change in the voltage dependence of steady-state currents. The activation of potassium channels was faster with ether present. There was no apparent change in the capacitance of the crayfish giant axon membrane with ether concentrations of up to 100 mM. Experiments on sodium channel inactivation kinetics were performed using 4-aminopyridine to block potassium currents. Sodium currents decayed with a time course generally fit well by a single exponential. The time constant of decay was a steep function of voltage, especially in the negative resistance region of the peak current vs voltage relation.The time course of inactivation was very similar to that of the decay of the current at the same potential. The measurement of steady-state inactivation curves with different test pulses showed no shifts along the voltage asix. The voltage-dependence of the integral of sodium conductance was measured to test models of sodium channel inactivation in which channels must open before inactivating; the results appear inconsistent with some of the simplest cases of such models.« less

Lifetime and dissolution kinetics of zinc oxide nanoparticles in aqueous media

NASA Astrophysics Data System (ADS)

Wang, Ning; Tong, Tiezheng; Xie, Minwei; Gaillard, Jean-François

2016-08-01

We have assessed the persistence and lifetime of ZnO nanoparticles (ZnO-NPs) by performing dissolution experiments in three different aqueous media. These experiments were performed at ZnO-NP concentration levels close to the solubility of zincite (˜8 μM or 650 μg l-1 of ZnO)—a concentration that is orders of magnitude higher than current estimated relevant environmental concentrations. The kinetics were followed by voltammetry, while maintaining the pH at about 7.5 using a CO2/N2 gas mixture to remove di-oxygen interference. Our results show that, under these conditions, ZnO-NPs readily dissolve with a lifetime expectancy that does not exceed 90 min. Water chemistry, especially the presence of dissolved organic matter (DOM), plays an important role in ZnO-NP dissolution. Dissolution rates significantly increase in the presence of strong chelating agents, EDTA and L-cysteine, while the addition of polymeric DOM, such as sodium alginate, has the opposite effect. Our results suggest that ZnO-NPs are unlikely to persist in natural aqueous media and that the toxicity should be primarily related to the released Zn2+ ions rather than effects commonly associated to the presence of nanoparticles.

Apparatus for detecting leakage of liquid sodium

DOEpatents

Himeno, Yoshiaki

1978-01-01

An apparatus for detecting the leakage of liquid sodium includes a cable-like sensor adapted to be secured to a wall of piping or other equipment having sodium on the opposite side of the wall, and the sensor includes a core wire electrically connected to the wall through a leak current detector and a power source. An accidental leakage of the liquid sodium causes the corrosion of a metallic layer and an insulative layer of the sensor by products resulted from a reaction of sodium with water or oxygen in the atmospheric air so as to decrease the resistance between the core wire and the wall. Thus, the leakage is detected as an increase in the leaking electrical current. The apparatus is especially adapted for use in detecting the leakage of liquid sodium from sodium-conveying pipes or equipment in a fast breeder reactor.

Analgesic ineffectiveness of lacosamide after spinal nerve ligation and its sodium channel activity in injured neurons.

PubMed

Hagenacker, T; Schäfer, N; Büsselberg, D; Schäfers, M

2013-07-01

Lacosamide is a novel anti-epileptic drug that enhances the slow- and not fast-inactivating state of voltage-gated sodium channels. Lacosamide has demonstrated analgesic efficacy in several animal studies but preclinical studies on neuropathic pain models are rare, and recent clinical trials showed no superior analgesic effects. Here, we examine whether an acute or chronic administration of lacosamide (3-60 mg/kg, i.p.) attenuates pain behaviour induced by spinal nerve ligation (SNL). To validate the inhibitory efficacy of lacosamide on voltage-gated sodium channels, sodium currents in naïve and SNL-injured dorsal root ganglion (DRG) neurons were recorded using whole-cell patch clamping. Lacosamide only marginally attenuated thermal hyperalgesia, but not tactile allodynia when applied once 7 or 14 days after SNL and showed no analgesic effect when applied daily for 19 days. In naïve neurons, 100 μmol/L lacosamide inhibited sodium channel currents by 58% and enhanced the slow inactivation (87% for lacosamide vs. 47% for control). In contrast, lacosamide inhibited sodium currents in injured DRG neurons by only 15%, while the effects on slow inactivation were diminished. Isolated currents from the NaV 1.8 channel subtype were only marginally changed by lacosamide. The reduced effectiveness of lacosamide on voltage-gated sodium channel currents in injured DRG neurons may contribute to the reduced analgesic effect observed for the SNL model. © 2012 European Federation of International Association for the Study of Pain Chapters.

Biodegradability of Corexit 9500 and Dispersed South Louisiana Crude Oil at 5 and 25oC

EPA Science Inventory

The reported persistence of the dioctyl sodium sulfosuccinate (DOSS) surfactant in Corexit 9500 in the oil plumes formed during the Deepwater Horizon oil spill has contributed to the concerns regarding the biodegradability and bioavailability of dispersed oil and dispersants used...

Biochar soil additions impacts herbicide fate: Importance of application timing and feedstock species

USDA-ARS?s Scientific Manuscript database

BACKGROUND: Biochar (BC), solid biomass subjected to pyrolysis, can alter the fate of pesticides in soil. We investigated the effect of soil amendment with several biochars on the sorption, persistence, leaching and bioefficacy of the herbicides clomazone (CMZ) and bispyribac sodium (BYP). RESULTS:...

Method of making a current collector for a sodium/sulfur battery

DOEpatents

Tischer, R.P.; Winterbottom, W.L.; Wroblowa, H.S.

1987-03-10

This specification is directed to a method of making a current collector for a sodium/sulfur battery. The current collector so-made is electronically conductive and resistant to corrosive attack by sulfur/polysulfide melts. The method includes the step of forming the current collector for the sodium/sulfur battery from a composite material formed of aluminum filled with electronically conductive fibers selected from the group of fibers consisting essentially of graphite fibers having a diameter up to 10 microns and silicon carbide fibers having a diameter in a range of 500--1,000 angstroms. 2 figs.

Method of making a current collector for a sodium/sulfur battery

DOEpatents

Tischer, Ragnar P.; Winterbottom, Walter L.; Wroblowa, Halina S.

1987-01-01

This specification is directed to a method of making a current collector (14) for a sodium/sulfur battery (10). The current collector so-made is electronically conductive and resistant to corrosive attack by sulfur/polysulfide melts. The method includes the step of forming the current collector for the sodium/sulfur battery from a composite material (16) formed of aluminum filled with electronically conductive fibers selected from the group of fibers consisting essentially of graphite fibers having a diameter up to 10 microns and silicon carbide fibers having a diameter in a range of 500-1000 angstroms.

Current Regulator For Sodium-Vapor Lamps

NASA Technical Reports Server (NTRS)

Mclyman, W. T.

1989-01-01

Regulating circuit maintains nearly-constant alternating current in sodium-vapor lamp. Regulator part of dc-to-ac inverter circuit used to supply power to street lamp from battery charged by solar-cell array.

Idraparinux sodium: SANORG 34006, SR 34006.

PubMed

2004-01-01

Idraparinux sodium [SANORG 34006, SR 34006], a synthetic, anti Xa pentasaccharide and analogue of SR 32701 and fondaparinux sodium, was in development with Sanofi (now Sanofi-Synthélabo) and Organon (Akzo Nobel) in Europe and the USA (now Sanofi-Synthélabo alone). It may have potential in the treatment and secondary prevention of thrombosis, especially deep-vein thrombosis (DVT). Because of the long duration of action of idraparinux sodium, it may be suitable for once-weekly administration. In January 2004, Sanofi-Synthélabo announced it was to acquire, before the end of the first quarter 2004, all the rights of Organon relating to idraparinux sodium, subject to approval of the regulatory authorities. Sanofi-Synthélabo is to make payments to Organon based on future sales. Idraparinux sodium has completed phase IIb development with the PERSIST study and it is in phase III clinical trials. In June 2003, Organon announced the initiation of pivotal phase III studies as a once-weekly treatment of DVT and pulmonary embolism (PE), and for the prevention of stroke in patients with atrial fibrillation. The AMADEUS study will focus on patients with atrial fibrillation while the Van Gogh PE, Van Gogh DVT and the Van Gogh extension (EXT) will focus on patients with DVT or PE.

Dietary sodium, adiposity, and inflammation in healthy adolescents.

PubMed

Zhu, Haidong; Pollock, Norman K; Kotak, Ishita; Gutin, Bernard; Wang, Xiaoling; Bhagatwala, Jigar; Parikh, Samip; Harshfield, Gregory A; Dong, Yanbin

2014-03-01

To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (β = 0.23), BMI (β = 0.23), waist circumference (β = 0.23), percent body fat (β = 0.17), fat mass (β = 0.23), subcutaneous abdominal adipose tissue (β = 0.25), leptin (β = 0.20), and tumor necrosis factor-α (β = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption.

Dietary Sodium, Adiposity, and Inflammation in Healthy Adolescents

PubMed Central

Pollock, Norman K.; Kotak, Ishita; Gutin, Bernard; Wang, Xiaoling; Bhagatwala, Jigar; Parikh, Samip; Harshfield, Gregory A.; Dong, Yanbin

2014-01-01

OBJECTIVES: To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. METHODS: A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. RESULTS: The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (β = 0.23), BMI (β = 0.23), waist circumference (β = 0.23), percent body fat (β = 0.17), fat mass (β = 0.23), subcutaneous abdominal adipose tissue (β = 0.25), leptin (β = 0.20), and tumor necrosis factor-α (β = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). CONCLUSIONS: The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption. PMID:24488738

21 CFR 184.1768 - Sodium lactate.

Code of Federal Regulations, 2014 CFR

2014-04-01

....1768 Sodium lactate. (a) Sodium lactate (C3H5O3Na, CAS Reg. No. 72-17-3) is the sodium salt of lactic acid. It is prepared commercially by the neutralization of lactic acid with sodium hydroxide. (b) The... ingredient is used in food at levels not to exceed current good manufacturing practice. (d) Prior sanctions...

Management of Teeth with Persistent Apical Periodontitis after Root Canal Treatment Using Regenerative Endodontic Therapy.

PubMed

Saoud, Tarek Mohamed A; Huang, George T-J; Gibbs, Jennifer L; Sigurdsson, Asgeir; Lin, Louis M

2015-10-01

Regenerative endodontic therapy (RET) is currently used to treat immature teeth with necrotic pulp and/or apical periodontitis. However, recently RET has been used to treat mature teeth with necrotic pulp and/or apical periodontitis and resulted in regression of clinical signs and/or symptoms and resolution of apical periodontitis. The purpose of this case report was to describe the potential of using RET to treat 2 mature teeth with persistent apical periodontitis after root canal therapy using RET. Two male patients, one 26-year old and another 12-year old, presented for retreatment of persistent apical periodontitis after root canal treatment of 2 mature teeth (#9 and #19). The gutta-percha fillings in the canals of teeth #9 and #19 were removed with Carvene gutta-percha solvent (Prevest DenPro, Jammu, India) and ProTaper Universal rotary retreatment files (Dentsply Maillefer, Ballaigues, Switzerland). The canals of both teeth were further chemomechanically debrided with rotary retreatment files and copious amounts of sodium hypochlorite irrigation and dressed with Metapaste (Meta Biomed, Chungbuk, Korea). RET was performed on teeth #9 and #19. Periapical bleeding was provoked into the disinfected root canals. The blood clots were covered with mineral trioxide aggregate plugs, and the access cavities were restored with intermediate restorative material. Teeth #9 and #19 showed regression of clinical signs and/or symptoms and healing of apical periodontitis after 13-month and 14-month follow-ups, respectively. Tooth #9 revealed narrowing of the canal space and apical closure by deposition of hard tissue. RET has the potential to be used to retreat teeth with persistent apical periodontitis after root canal therapy. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Genetic and phenotypic heterogeneity suggest therapeutic implications in SCN2A-related disorders.

PubMed

Wolff, Markus; Johannesen, Katrine M; Hedrich, Ulrike B S; Masnada, Silvia; Rubboli, Guido; Gardella, Elena; Lesca, Gaetan; Ville, Dorothée; Milh, Mathieu; Villard, Laurent; Afenjar, Alexandra; Chantot-Bastaraud, Sandra; Mignot, Cyril; Lardennois, Caroline; Nava, Caroline; Schwarz, Niklas; Gérard, Marion; Perrin, Laurence; Doummar, Diane; Auvin, Stéphane; Miranda, Maria J; Hempel, Maja; Brilstra, Eva; Knoers, Nine; Verbeek, Nienke; van Kempen, Marjan; Braun, Kees P; Mancini, Grazia; Biskup, Saskia; Hörtnagel, Konstanze; Döcker, Miriam; Bast, Thomas; Loddenkemper, Tobias; Wong-Kisiel, Lily; Baumeister, Friedrich M; Fazeli, Walid; Striano, Pasquale; Dilena, Robertino; Fontana, Elena; Zara, Federico; Kurlemann, Gerhard; Klepper, Joerg; Thoene, Jess G; Arndt, Daniel H; Deconinck, Nicolas; Schmitt-Mechelke, Thomas; Maier, Oliver; Muhle, Hiltrud; Wical, Beverly; Finetti, Claudio; Brückner, Reinhard; Pietz, Joachim; Golla, Günther; Jillella, Dinesh; Linnet, Karen M; Charles, Perrine; Moog, Ute; Õiglane-Shlik, Eve; Mantovani, John F; Park, Kristen; Deprez, Marie; Lederer, Damien; Mary, Sandrine; Scalais, Emmanuel; Selim, Laila; Van Coster, Rudy; Lagae, Lieven; Nikanorova, Marina; Hjalgrim, Helle; Korenke, G Christoph; Trivisano, Marina; Specchio, Nicola; Ceulemans, Berten; Dorn, Thomas; Helbig, Katherine L; Hardies, Katia; Stamberger, Hannah; de Jonghe, Peter; Weckhuysen, Sarah; Lemke, Johannes R; Krägeloh-Mann, Ingeborg; Helbig, Ingo; Kluger, Gerhard; Lerche, Holger; Møller, Rikke S

2017-05-01

Mutations in SCN2A, a gene encoding the voltage-gated sodium channel Nav1.2, have been associated with a spectrum of epilepsies and neurodevelopmental disorders. Here, we report the phenotypes of 71 patients and review 130 previously reported patients. We found that (i) encephalopathies with infantile/childhood onset epilepsies (≥3 months of age) occur almost as often as those with an early infantile onset (<3 months), and are thus more frequent than previously reported; (ii) distinct phenotypes can be seen within the late onset group, including myoclonic-atonic epilepsy (two patients), Lennox-Gastaut not emerging from West syndrome (two patients), and focal epilepsies with an electrical status epilepticus during slow sleep-like EEG pattern (six patients); and (iii) West syndrome constitutes a common phenotype with a major recurring mutation (p.Arg853Gln: two new and four previously reported children). Other known phenotypes include Ohtahara syndrome, epilepsy of infancy with migrating focal seizures, and intellectual disability or autism without epilepsy. To assess the response to antiepileptic therapy, we retrospectively reviewed the treatment regimen and the course of the epilepsy in 66 patients for which well-documented medical information was available. We find that the use of sodium channel blockers was often associated with clinically relevant seizure reduction or seizure freedom in children with early infantile epilepsies (<3 months), whereas other antiepileptic drugs were less effective. In contrast, sodium channel blockers were rarely effective in epilepsies with later onset (≥3 months) and sometimes induced seizure worsening. Regarding the genetic findings, truncating mutations were exclusively seen in patients with late onset epilepsies and lack of response to sodium channel blockers. Functional characterization of four selected missense mutations using whole cell patch-clamping in tsA201 cells-together with data from the literature-suggest that mutations associated with early infantile epilepsy result in increased sodium channel activity with gain-of-function, characterized by slowing of fast inactivation, acceleration of its recovery or increased persistent sodium current. Further, a good response to sodium channel blockers clinically was found to be associated with a relatively small gain-of-function. In contrast, mutations in patients with late-onset forms and an insufficient response to sodium channel blockers were associated with loss-of-function effects, including a depolarizing shift of voltage-dependent activation or a hyperpolarizing shift of channel availability (steady-state inactivation). Our clinical and experimental data suggest a correlation between age at disease onset, response to sodium channel blockers and the functional properties of mutations in children with SCN2A-related epilepsy. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Free standing Cu2Te, new anode material for sodium-ion battery

NASA Astrophysics Data System (ADS)

Sarkar, Ananta; Mallick, Md. Mofasser; Panda, Manas Ranjan; Vitta, Satish; Mitra, Sagar

2018-05-01

Sodium-ion battery is the most popular alternative to lithium-ion energy storage system due to its low cost and huge abundant resources throughout the world. Although recent literature showed cathode materials for sodium ion battery performs almost equivalent to lithium-ion counterpart but the anode of this sodium-ion battery is in premature state. Here, we introduced free-standing copper telluride (Cu2Te), a new anode materials for sodium-ion battery. For making the electrode we did not use any conductive carbon or current collector which increase the volumetric density as well as reduce the cost of the cell. This metallic Cu2Te alloy exhibited a high reversible capacity of ˜275 mAh g-1 at 50 mA g-1 current density and ˜200 mAh g-1 at higher current density of 100 mA g-1, operating between 0.1 to 2.0 V.

Drinking water sodium and blood pressure in children: a second look.

PubMed Central

Tuthill, R W; Calabrese, E J

1981-01-01

A previous study by the current authors demonstrated a statistically significant and clinically important elevation of 3-5 mmHg in mean systolic and diastolic blood pressure in high school sophomores in a community with 108 mg/L of sodium in the water supply when compared to their peers in an appropriately matched community with 8 mg/L of sodium. The current investigation, employing identical techniques but studying third graders in the same two communities, showed similar results. This second look considered dietary intake and urinary excretion of sodium. Since the difference in 24-hour dietary sodium consumption was 300 milligrams between the communities, an intake of one liter of high sodium tap water represented approximately 25 per cent of the difference in total sodium intake between the two communities. These studies suggest that sodium consumption in both drinking water and diet may be contributing to the different blood pressure distributions among the normotensive children in the two communities. PMID:7246839

Inhibition of tetrodotoxin-resistant sodium current in dorsal root ganglia neurons mediated by D1/D5 dopamine receptors

PubMed Central

2013-01-01

Background Dopaminergic fibers originating from area A11 of the hypothalamus project to different levels of the spinal cord and represent the major source of dopamine. In addition, tyrosine hydroxylase, the rate-limiting enzyme for the synthesis of catecholamines, is expressed in 8-10% of dorsal root ganglia (DRG) neurons, suggesting that dopamine may be released in the dorsal root ganglia. Dopamine has been shown to modulate calcium current in DRG neurons, but the effects of dopamine on sodium current and on the firing properties of small DRG neurons are poorly understood. Results The effects of dopamine and dopamine receptor agonists were tested on the tetrodotoxin-resistant (TTX-R) sodium current recorded from acutely dissociated small (diameter ≤ 25 μm) DRG neurons. Dopamine (20 μM) and SKF 81297 (10 μM) caused inhibition of TTX-R sodium current in small DRG neurons by 23% and 37%, respectively. In contrast, quinpirole (20 μM) had no effects on the TTX-R sodium current. Inhibition by SKF 81297 of the TTX-R sodium current was not affected when the protein kinase A (PKA) activity was blocked with the PKA inhibitory peptide (6–22), but was greatly reduced when the protein kinase C (PKC) activity was blocked with the PKC inhibitory peptide (19–36), suggesting that activation of D1/D5 dopamine receptors is linked to PKC activity. Expression of D1and D5 dopamine receptors in small DRG neurons, but not D2 dopamine receptors, was confirmed by Western blotting and immunofluorescence analysis. In current clamp experiments, the number of action potentials elicited in small DRG neurons by current injection was reduced by ~ 30% by SKF 81297. Conclusions We conclude that activation of D1/D5 dopamine receptors inhibits TTX-R sodium current in unmyelinated nociceptive neurons and dampens their intrinsic excitability by reducing the number of action potentials in response to stimulus. Increasing or decreasing levels of dopamine in the dorsal root ganglia may serve to adjust the sensitivity of nociceptors to noxious stimuli. PMID:24283218

The treatment of type 1 diabetes mellitus with agents approved for type 2 diabetes mellitus.

PubMed

Munir, Kashif M; Davis, Stephen N

2015-01-01

The management of type 1 diabetes remains a challenge for clinicians. Current practice is to administer insulin analogues to best mimic normal physiological insulin profiles. However, despite our best efforts the majority of individuals with type 1 diabetes continue to suffer from suboptimal glucose control, significant hypoglycemia and microvascular tissue complications of the disease. There is thus a significant unmet need in the treatment of T1DM to obtain better glycemic control. We discuss the use of α-glucosidase inhibitors, dipeptidyl-peptidase inhibitors, glucagon-like peptide 1 agonists, biguanides, thiazolidinediones and sodium glucose co-transporter 2 inhibitors in individuals with T1DM. Non-insulin therapies present a unique and exciting adjunctive treatment for individuals with type 1 diabetes. Although data are scarce, the classes of medications discussed help to lower glucose, decrease glycemic excursions and in some cases improve body weight, along with allowing dose reductions in total daily insulin. Glucagon-like peptide 1 agonists and sodium glucose co-transporter 2 inhibitors, in particular, have been demonstrated to provide clinical improvements in individuals with T1DM and we feel their use can be explored in obese, insulin-resistant patients with T1DM, those with frequent and significant glycemic excursions or individuals with persistently elevated hemoglobin A1c.

Comparison of fluorescence probes for intracellular sodium imaging in prostate cancer cell lines.

PubMed

Iamshanova, Oksana; Mariot, Pascal; Lehen'kyi, V'yacheslav; Prevarskaya, Natalia

2016-10-01

Sodium (Na + ) ions are known to regulate many signaling pathways involved in both physiological and pathological conditions. In particular, alterations in intracellular concentrations of Na + and corresponding changes in membrane potential are known to be major actors of cancer progression to metastatic phenotype. Though the functionality of Na + channels and the corresponding Na + currents can be investigated using the patch-clamp technique, the latter is rather invasive and a technically difficult method to study intracellular Na + transients compared to Na + fluorescence imaging. Despite the fact that Na + signaling is considered an important controller of cancer progression, only few data using Na + imaging approaches are available so far, suggesting the persisting challenge within the scientific community. In this study, we describe in detail the approach for application of Na + imaging technique to measure intracellular Na + variations in human prostate cancer cells. Accordingly, we used three Na + -specific fluorescent dyes-Na + -binding benzofuran isophthalate (SBFI), CoroNa™ Green (Corona) and Asante NaTRIUM Green-2 (ANG-2). These dyes have been assessed for optimal loading conditions, dissociation constant and working range after different calibration methods, and intracellular Na + sensitivity, in order to determine which probe can be considered as the most reliable to visualize Na + fluctuations in vitro.

Estimates of Dietary Sodium Consumption in Patients With Chronic Heart Failure.

PubMed

Colin-Ramirez, Eloisa; Arcand, JoAnne; Ezekowitz, Justin A

2015-12-01

Estimating dietary sodium intake is a key component of dietary assessment in the clinical setting of HF to effectively implement appropriate dietary interventions for sodium reduction and monitor adherence to the dietary treatment. In a research setting, assessment of sodium intake is crucial to an essential methodology to evaluate outcomes after a dietary or behavioral intervention. Current available sodium intake assessment methods include 24-hour urine collection, spot urine collections, multiple day food records, food recalls, and food frequency questionnaires. However, these methods have inherent limitations that make assessment of sodium intake challenging, and the utility of traditional methods may be questionable for estimating sodium intake in patients with HF. Thus, there are remaining questions about how to best assess dietary sodium intake in this patient population, and there is a need to identify a reliable method to assess and monitor sodium intake in the research and clinical setting of HF. This paper provides a comprehensive review of the current methods for sodium intake assessment, addresses the challenges for its accurate evaluation, and highlights the relevance of applying the highest-quality measurement methods in the research setting to minimize the risk of biased data. Copyright © 2015 Elsevier Inc. All rights reserved.

Kinetic and functional analysis of transient, persistent and resurgent sodium currents in rat cerebellar granule cells in situ: an electrophysiological and modelling study

PubMed Central

Magistretti, Jacopo; Castelli, Loretta; Forti, Lia; D'Angelo, Egidio

2006-01-01

Cerebellar neurones show complex and differentiated mechanisms of action potential generation that have been proposed to depend on peculiar properties of their voltage-dependent Na+ currents. In this study we analysed voltage-dependent Na+ currents of rat cerebellar granule cells (GCs) by performing whole-cell, patch-clamp experiments in acute rat cerebellar slices. A transient Na+ current (INaT) was always present and had the properties of a typical fast-activating/inactivating Na+ current. In addition to INaT, robust persistent (INaP) and resurgent (INaR) Na+ currents were observed. INaP peaked at ∼−40 mV, showed half-maximal activation at ∼−55 mV, and its maximal amplitude was about 1.5% of that of INaT. INaR was elicited by repolarizing pulses applied following step depolarizations able to activate/inactivate INaT, and showed voltage- and time-dependent activation and voltage-dependent decay kinetics. The conductance underlying INaR showed a bell-shaped voltage dependence, with peak at −35 mV. A significant correlation was found between GC INaR and INaT peak amplitudes; however, GCs expressing INaT of similar size showed marked variability in terms of INaR amplitude, and in a fraction of cells INaR was undetectable. INaT, INaP and INaR could be accounted for by a 13-state kinetic scheme comprising closed, open, inactivated and blocked states. Current-clamp experiments carried out to identify possible functional correlates of INaP and/or INaR revealed that in GCs single action potentials were followed by depolarizing afterpotentials (DAPs). In a majority of cells, DAPs showed properties consistent with INaR playing a role in their generation. Computer modelling showed that INaR promotes DAP generation and enhances high-frequency firing, whereas INaP boosts near-threshold firing activity. Our findings suggest that special properties of voltage-dependent Na+ currents provides GCs with mechanisms suitable for shaping activity patterns, with potentially important consequences for cerebellar information transfer and computation. PMID:16527854

Reduced Sodium Current in the Lateral Ventricular Wall Induces Inferolateral J-Waves.

PubMed

Meijborg, Veronique M F; Potse, Mark; Conrath, Chantal E; Belterman, Charly N W; De Bakker, Jacques M T; Coronel, Ruben

2016-01-01

J-waves in inferolateral leads are associated with a higher risk for idiopathic ventricular fibrillation. We aimed to test potential mechanisms (depolarization or repolarization dependent) responsible for inferolateral J-waves. We hypothesized that inferolateral J-waves can be caused by regional delayed activation of myocardium that is activated late during normal conditions. Computer simulations were performed to evaluate how J-point elevation is influenced by reducing sodium current conductivity (GNa), increasing transient outward current conductivity (Gto), or cellular uncoupling in three predefined ventricular regions (lateral, anterior, or septal). Two pig hearts were Langendorff-perfused with selective perfusion with a sodium channel blocker of lateral or anterior/septal regions. Volume-conducted pseudo-electrocardiograms (ECG) were recorded to detect the presence of J-waves. Epicardial unipolar electrograms were simultaneously recorded to obtain activation times (AT). Simulation data showed that conduction slowing, caused by reduced sodium current, in lateral, but not in other regions induced inferolateral J-waves. An increase in transient outward potassium current or cellular uncoupling in the lateral zone elicited slight J-point elevations which did not meet J-wave criteria. Additional conduction slowing in the entire heart attenuated J-waves and J-point elevations on the ECG, because of masking by the QRS. Experimental data confirmed that conduction slowing attributed to sodium channel blockade in the left lateral but not in the anterior/septal ventricular region induced inferolateral J-waves. J-waves coincided with the delayed activation. Reduced sodium current in the left lateral ventricular myocardium can cause inferolateral J-waves on the ECG.

Effects of cell volume changes on membrane ionic permeabilities and sodium transport in frog skin (Rana ridibunda).

PubMed

Costa, P M; Fernandes, P L; Ferreira, H G; Ferreira, K T; Giraldez, F

1987-12-01

1. Membrane potential and conductances and short-circuit current were continuously measured with microelectrodes and conventional electrophysiological techniques in a stripped preparation of frog skin epithelium. The effects of the removal of chloride or sodium ions and the concentration or dilution of the serosal (inner) bathing solution were studied. 2. Chloride- or sodium-free solutions produced a cell depolarization of about 30 mV in parallel with a fall in the short-circuit current. Mucosal and serosal membrane conductances both decreased and the sodium permeability of the mucosal barrier was calculated to fall to about one-half its value in standard Ringer solution. The observed decrease in the short-circuit current is probably related to the combined effect of the decrease in sodium permeability and the decrease in the driving force across the mucosal membrane. 3. The removal of chloride or sodium ions reduced the depolarization caused by serosal perfusion with high-potassium solutions (50 mM-KCl). The ratio of the change in cell membrane potential under short-circuit conditions to the change in the potassium equilibrium potential (delta Ec(s.c.)/delta EK), was 0.59 in standard Ringer solution and 0.26 and 0.24 after the removal of chloride or sodium respectively. The depolarizing effect of barium-containing solutions (2 mM-BaCl2) was also markedly reduced in chloride- or sodium-free solutions, suggesting a decrease of the potassium selectivity of the serosal membrane in these conditions. 4. Increasing the osmolality of the serosal bathing solution produced similar effects, i.e. cell depolarization, fall in the short-circuit current and membrane conductances and reduction of the depolarizing effect of high-potassium and barium solutions. On the contrary, dilution of the serosal bath produced the opposite effects, consistent with an increase in the serosal permeability to potassium. 5. The effects of chloride- or sodium-free solutions were reversed by the dilution of the serosal bath. Cells repolarized when exposed to low-osmolality solutions after being in the absence of serosal chloride or sodium. The repolarization ran in parallel with the restoration of the short-circuit current and the potassium selectivity of the serosal membrane. 6. The results show that the effects produced by the removal of sodium or chloride ions from the serosal bathing solution are most probably mediated by a reduction in cell volume. Cell volume changes would lead to changes in the serosal membrane selectivity to potassium and thus to changes in cell membrane potential and sodium transport.(ABSTRACT TRUNCATED AT 400 WORDS)

Vitex negundo induces an anticonvulsant effect by inhibiting voltage gated sodium channels in murine Neuro 2A cell line.

PubMed

Khan, Faisal; Saify, Zafar Saeed; Jamali, Khawar Saeed; Naz, Saima; Hassan, Sohail; Siddiqui, Sonia

2018-01-01

Vitex negundo (Vn) extract is famous for the treatment of neurological diseases such as migraine and epilepsy. These neurological diseases have been associated with abnormally increased influx of sodium ions into the neurons. Drugs that inhibit voltage gated sodium channels can be used as potent anti-epileptics. Till now, the effects of Vn on sodium channels have not been investigated. Therefore, we have investigated the effects of methalonic fraction of Vn extract in Murine Neuro 2A cell line. Cells were cultured in a defined medium with or without the Vn extract (100 μg/ml). Sodium currents were recorded using whole-cell patch clamp method. The data show that methanolic extract of Vn inhibited sodium currents in a dose dependent manner (IC50 =161μg/ml). Vn (100 μg/ml) shifted the steady-state inactivation curve to the left or towards the hyper polarization state. However, Vn did not show any effects on outward rectifying potassium currents. Moreover, Vn (100 μg/ml) significantly reduced the sustained repetitive (48±4.8%, P<0.01) firing from neonatal hippocampal neurons at 12 DIV. Hence, our data suggested that inhibition of sodium channels by Vn may exert pharmacological effects in reducing pain and convulsions.

The U.S. Department of Agriculture Automated Multiple-Pass Method accurately assesses sodium intakes

USDA-ARS?s Scientific Manuscript database

Accurate and practical methods to monitor sodium intake of the U.S. population are critical given current sodium reduction strategies. While the gold standard for estimating sodium intake is the 24 hour urine collection, few studies have used this biomarker to evaluate the accuracy of a dietary ins...

3D free-standing nitrogen-doped reduced graphene oxide aerogel as anode material for sodium ion batteries with enhanced sodium storage.

PubMed

Zhang, Jiao; Li, Chuanqi; Peng, Zhikun; Liu, Yushan; Zhang, Jianmin; Liu, Zhongyi; Li, Dan

2017-07-07

Sodium ion batteries have drawn extensive attentions for large-scale energy storage to replace lithium ion batteries primarily due to the natural abundance of sodium resource and low cost, but their energy density and electrochemical performance are hindered by the sluggish diffusion kinetics of sodium ion. Herein, free-standing nitrogen-doped graphene aerogel has been fabricated via hydrothermal reaction as the potential anode material for sodium ion batteries. The three dimensional porous network structure of the graphene aerogel provides sufficient interstitial space for sodium ion accommodation, allowing fast and reversible ion intercalation/de-intercalation. The nitrogen doping could introduce defects on the graphene sheets, making the feasible transport of large-sized sodium ion. Benefiting from the effective structure and nitrogen doping, the obtained material demonstrates high reversible capacities, good cycling performance (287.9 mA h g -1 after 200 cycles at a current density of 100 mA g -1 ), especially superior rate capability (151.9 mA h g -1 at a high current density of 5 A g -1 ).

Readthrough of SCN5A Nonsense Mutations p.R1623X and p.S1812X Questions Gene-therapy in Brugada Syndrome.

PubMed

Teng, Siyong; Huang, Jian; Gao, Zhan; Hao, Jie; Yang, Yuejin; Zhang, Shu; Pu, Jielin; Hui, Rutai; Wu, Yongjian; Fan, Zheng

2017-01-01

Nonsense mutation readthrough is used as a gene-specific treatment in some genetic diseases. The response to readthrough treatment is determined by the readthrough efficiency of various nonsense mutations. In this manuscript, we aimed to explore the harmful effects of nonsense mutation suppression. HEK293 cells were transfected with two SCN5A (encode cardiac Na+ channel) nonsense mutations, p.R1623X and p.S1812X. We applied two readthrough-enhancing methods (either aminoglycosides or a siRNA-targeting eukaryotic release factor eRF3a (a GTPase that binds eRF1)) to suppress these SCN5A nonsense mutations. When either of readthrough methods was used, the sodium channel proteins were examined by western blot and immunoblotting and recorded by whole cell patch-clamp to observe the functional characterization of the restored channels. Upon readthrough treatment, the sodium currents were restored to the mutant cDNAs. These mutations reduced full-length sodium channel protein levels, and the sodium currents were reduced to 3% of wild-type. The mutant cDNA sodium currents were increased to 30% of wild-type, and the fulllength proteins also increased. However, the functional characterization of these channels from cDNAs carrying p.R1623X and p.S1812X exhibited abnormal biophysical properties, including a negative shift in steady-state sodium channel inactivation, a positive shift in sodium channel activation and robust late sodium currents. The ramp test showed prolonged QT intervals. These results demonstrated that readthrough-enhancing methods effectively suppressed nonsense mutations in SCN5A and restored the expression of full-length channels. However, the restored channels may increase the risk of arrhythmia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Diabetes insipidus as a rare cause of acute cognitive impairment in multiple sclerosis.

PubMed

Tiedje, V; Schlamann, M; Führer, D; Moeller, L C

2013-10-01

Multiple sclerosis (MS) is a complex neurodegenerative disease presenting with a diversity of clinical symptoms including palsy and cognitive impairment. We present a 59-year-old woman with a history of secondary progressive MS since 1987, who was referred to our department because of recent onset of confusion and polydipsia. Initial lab tests showed mildly elevated serum sodium levels and low urine osmolality. Under water deprivation, diuresis and low urine osmolality persisted and serum sodium levels rose above 150 mmol/l. Oral desmopressin resulted in normalisation of serum sodium as well as urine osmolarity, confirming a diagnosis of central diabetes insipidus. As drug-induced diabetes could be excluded, pituitary magnetic resonance imaging (MRI) was performed. A demyelinating lesion was detected in the hypothalamus. The patient was started on oral desmopressin treatment (0.2 mg/day). Fluid intake and serum sodium levels have since remained normal. In summary, we report the rare case of a patient presenting with diabetes insipidus due to progressive MS. Diabetes insipidus should be considered in MS patients who develop new onset of polydipsia.

Treatment of the syndrome of inappropriate secretion of antidiuretic hormone by urea.

PubMed

Decaux, G; Brimioulle, S; Genette, F; Mockel, J

1980-07-01

Recent data have shown the role of urea in the urinary concentrating mechanism. We studied the effects of exogenous urea administration in hyponatremia associated with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). In 20 patients with SIADH, we observed a positive correlation between serum sodium and blood urea levels (r = 0.65; p less than 0.01). In one patient with an oat cell carcinoma and SIADH-induced hyponatremia, we observed the same positive correlation (r = 0.80; p less than 0.01) but also a negative one between the excreted fraction of filtered sodium and urinary urea (r = -0.67; p less than 0.001). The short-term administration of low doses of urea (4 to 10 g) resulted in correcting the "salt-losing" tendency of this patient. Longer term administration of high doses of urea (30 g/day) was attempted with the same patient as well as with a healthy volunteer subject with Pitressin-induced SIADH. in both patients, urea treatment lowered urinary sodium excretion as long as hyponatremia was significant (less than 130 meq/liter). Urea treatment also induced a persistent osmotic diuresis, allowing a normal daily intake of water despite SIADH. This was clearly shown during the long-term treatment of a third patient with SIADH who was taking 30 g urea/day during 11 weeks. It is concluded that urea is a good alternative in the treatment of patients with SIADH who presented with persistent hyponatremia despite the restriction of water intake.

The Effect of 8.25% Sodium Hypochlorite on Dental Pulp Dissolution and Dentin Flexural Strength and Modulus

DTIC Science & Technology

2015-06-18

sodium hypochlorite (NaOCl) became a main irrigant in endodontics (6) and is currently the preferred endodontic ... sodium hypochlorite used during endodontic irrigation (8). Since there may be many different concentrations of sodium hypochlorite available, the dentist...A, Brandt M. Toxicity of concentrated sodium hypochlorite used as an endodontic irrigant. Int Endod J 2004;37:272–80. 18. Hulsmann M, Hahn

Ciguatoxins: Cyclic Polyether Modulators of Voltage-gated Iion Channel Function

PubMed Central

Nicholson, Graham M.; Lewis, Richard J.

2006-01-01

Ciguatoxins are cyclic polyether toxins, derived from marine dinoflagellates, which are responsible for the symptoms of ciguatera poisoning. Ingestion of tropical and subtropical fin fish contaminated by ciguatoxins results in an illness characterised by neurological, cardiovascular and gastrointestinal disorders. The pharmacology of ciguatoxins is characterised by their ability to cause persistent activation of voltage-gated sodium channels, to increase neuronal excitability and neurotransmitter release, to impair synaptic vesicle recycling, and to cause cell swelling. It is these effects, in combination with an action to block voltage-gated potassium channels at high doses, which are believed to underlie the complex of symptoms associated with ciguatera. This review examines the sources, structures and pharmacology of ciguatoxins. In particular, attention is placed on their cellular modes of actions to modulate voltage-gated ion channels and other Na+-dependent mechanisms in numerous cell types and to current approaches for detection and treatment of ciguatera.

Twenty‐Two‐Year Population Trends in Sodium and Potassium Consumption: The Minnesota Heart Survey

PubMed Central

Meyer, Katie A.; Harnack, Lisa J.; Luepker, Russell V.; Zhou, Xia; Jacobs, David R.; Steffen, Lyn M.

2013-01-01

Background Limiting dietary sodium consumption is a core lifestyle recommendation for the prevention of hypertension. There is increasing evidence that low potassium consumption also increases hypertension risk. We estimated sex‐specific 22‐year trends in sodium and potassium consumption. Methods and Results We used data from the Minnesota Heart Survey, which performs surveillance of risk factors for cardiovascular disease in the Minneapolis–St. Paul metropolitan area. The Minnesota Heart Survey is a random population‐based sample of free‐living adults aged 25 to 74. Surveys were conducted in 1985–1987 (n=2273), 1990–1992 (n=2487), 1995–1997 (n=1842), 2000–2002 (n=2759), and 2007–2009 (n=1502). Dietary intake of sodium and potassium was estimated from one 24‐hour dietary recall. Over 22 years, age‐adjusted sodium and potassium intake among men remained relatively stable in 1985–1987 and 2007–2009 (Ptrend=0.41 and 0.29, respectively); sodium ranged from 3820 mg/day (1995–1997) to 3968 mg/day (2007–2009) and potassium from 3111 mg/day (2000–2002) to 3249 mg/day (1995–1997). Sodium and potassium intake increased among women, from 2531 mg/day in 1985–1987 to 2854 mg/day in 2007–2009 (Ptrend=0.001) for sodium and from 2285 to 2533 mg/day (Ptrend<0.0001) for potassium. We observed stable or increasing sodium and potassium intake within some strata of age, education, and body mass index. Conclusions Despite long‐standing public health recommendations to limit sodium intake to <2300 mg/day, high sodium intake levels have persisted over the past 22 years. Furthermore, although potassium consumption increased in some subgroups over the study period, mean consumption remained significantly lower than the recommended 4700 mg/day in all groups. PMID:24088508

Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water.

PubMed

Wolfe, Marlene K; Gallandat, Karin; Daniels, Kyle; Desmarais, Anne Marie; Scheinman, Pamela; Lantagne, Daniele

2017-01-01

To prevent Ebola transmission, frequent handwashing is recommended in Ebola Treatment Units and communities. However, little is known about which handwashing protocol is most efficacious. We evaluated six handwashing protocols (soap and water, alcohol-based hand sanitizer (ABHS), and 0.05% sodium dichloroisocyanurate, high-test hypochlorite, and stabilized and non-stabilized sodium hypochlorite solutions) for 1) efficacy of handwashing on the removal and inactivation of non-pathogenic model organisms and, 2) persistence of organisms in rinse water. Model organisms E. coli and bacteriophage Phi6 were used to evaluate handwashing with and without organic load added to simulate bodily fluids. Hands were inoculated with test organisms, washed, and rinsed using a glove juice method to retrieve remaining organisms. Impact was estimated by comparing the log reduction in organisms after handwashing to the log reduction without handwashing. Rinse water was collected to test for persistence of organisms. Handwashing resulted in a 1.94-3.01 log reduction in E. coli concentration without, and 2.18-3.34 with, soil load; and a 2.44-3.06 log reduction in Phi6 without, and 2.71-3.69 with, soil load. HTH performed most consistently well, with significantly greater log reductions than other handwashing protocols in three models. However, the magnitude of handwashing efficacy differences was small, suggesting protocols are similarly efficacious. Rinse water demonstrated a 0.28-4.77 log reduction in remaining E. coli without, and 0.21-4.49 with, soil load and a 1.26-2.02 log reduction in Phi6 without, and 1.30-2.20 with, soil load. Chlorine resulted in significantly less persistence of E. coli in both conditions and Phi6 without soil load in rinse water (p<0.001). Thus, chlorine-based methods may offer a benefit of reducing persistence in rinse water. We recommend responders use the most practical handwashing method to ensure hand hygiene in Ebola contexts, considering the potential benefit of chlorine-based methods in rinse water persistence.

D-amino acids reduce Enterococcus faecalis biofilms in vitro and in the presence of antimicrobials used for root canal treatment.

PubMed

Zilm, Peter S; Butnejski, Victor; Rossi-Fedele, Giampiero; Kidd, Stephen P; Edwards, Suzanne; Vasilev, Krasimir

2017-01-01

Enterococcus faecalis is the most frequent species present in post-treatment disease and plays a significant role in persistent periapical infections following root canal treatment. Its ability to persist in stressful environments is inter alia, due to its ability to form biofilms. The presence of certain D-amino acids (DAAs) has previously been shown to reduce formation of Bacillus subtilis biofilms. The aims of this investigation were to determine if DAAs disrupt biofilms in early and late growth stages for clinical E. faecalis strains and to test their efficacy in disrupting E. faecalis biofilms grown in sub-minimum inhibitory concentrations of commonly used endodontic biocides. From thirty-seven E. faecalis strains, the ten "best" biofilm producers were used to test the ability of a mixture containing D-leucine, D-methionine, D-tyrosine and D-tryptophan to reduce biofilm growth over a period of 24, 72 and 144 hours and when compared to their cognate L-Amino Acids (LAAs). We have previously shown that sub-MIC levels of tetracycline and sodium hypochlorite promotes biofilm growth in clinical strains of E. faecalis. DAAs were therefore tested for their effectiveness to reduce biofilm growth in the presence of sub-minimal concentrations of sodium hypochlorite (NaOCl-0.031%) and Odontocide™ (0.25% w/v), and in the presence of Odontopaste™ (0.25% w/v). DAAs significantly reduced biofilm formation for all strains tested in vitro, while DAAs significantly reduced biofilm formation compared to LAAs. The inhibitory effect of DAAs on biofilm formation was concentration dependent. DAAs were also shown to be effective in reducing E. faecalis biofilms in the presence of Odontopaste™ and sub-MIC levels of NaOCl and Odontocide™. The results suggest that the inclusion of DAAs into current endodontic procedures may reduce E. faecalis biofilms.

The Mercury exosphere after MESSENGER

NASA Astrophysics Data System (ADS)

Killen, Rosemary; McClintock, William; Vervack, Ronald; Merkel, Aimee; Burger, Matthew; Cassidy, Timothy; Sarantos, Menelaos

2016-07-01

The Mercury Atmospheric and Surface Composition Spectrometer (MASCS) on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft observed sodium, calcium and magnesium emisison in Mercury's exosphere on a near-daily basis for >16 Mercury years. The MASCS observations showed that calcium in Mercury's exosphere is persistently concentrated in the dawn hemisphere and is of extreme temperature (>50,000 K). The column abundance varies seasonally, and is extremely repeatable each Mercury year. In addition, the calcium exhibits a persistent maximum not at perihelion but 20° after perihelion, an enhancement that was shown to be coincident with the probable intersection of Mercury's orbit with a dust stream originating at Comet Encke. Any mechanism producing the Mercurian Ca exosphere must explain the facts that the Ca is extremely hot, that it is seen almost exclusively on the dawnside of the planet, and that its content varies seasonally, not sporadically. Energization of the Ca atoms was suggested to originate through dissociation of Ca-bearing molecules ejected by meteoritic impacts. Magnesium was also observed on a daily basis throughout the MESSENGER orbital phase. Mg has its own spatial and temporal pattern, peaking at mid-morning instead of early morning like Ca, and exhibiting a warm thermal profile, about 5000 K, unlike the extreme temperature of Ca which is an order of magnitude hotter. Although Mercury's sodium exosphere has been observed from the ground for many decades, the MASCS observations showed that, like calcium, the sodium exosphere is dominated by seasonal variations, not sporadic variations. However a conundrum exists as to why ground-based observations show highly variable high-latitude variations that eluded the MASCS. The origin of a persistent south polar enhancement has not been explained. The more volatile element, Na, is again colder, about 1200 K, but not thermally accommodated to the surface temperature. A combination of source processes is surmised for this element, dominated by photon-stimulated desorption. Sporadic and high latitude enhancements persistently seen from the Earth have eluded measurement from orbit, possibly due to the geometry of the observations. One discovery still not fully explained is the observation that ionized calcium is almost as dense in the anti-sunward near tail as neutral calcium. The reason is most probably due to magnetospheric convection, but further work is needed to confirm this. Other weakly emitting species such as aluminum were observed sporadically, but most often near the dawn terminator.

Final report on the safety assessment of sodium cetearyl sulfate and related alkyl sulfates as used in cosmetics.

PubMed

Fiume, Monice; Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F

2010-05-01

Sodium cetearyl sulfate is the sodium salt of a mixture of cetyl and stearyl sulfate. The other ingredients in this safety assessment are also alkyl salts, including ammonium coco-sulfate, ammonium myristyl sulfate, magnesium coco-sulfate, sodium cetyl sulfate, sodium coco/hydrogenated tallow sulfate, sodium coco-sulfate, sodium decyl sulfate, sodium ethylhexyl sulfate, sodium myristyl sulfate, sodium oleyl sulfate, sodium stearyl sulfate, sodium tallow sulfate, sodium tridecyl sulfate, and zinc coco-sulfate. These ingredients are surfactants used at concentrations from 0.1% to 29%, primarily in soaps and shampoos. Many of these ingredients are not in current use. The Cosmetic Ingredient Review (CIR) Expert Panel previously completed a safety assessment of sodium and ammonium lauryl sulfate. The data available for sodium lauryl sulfate and ammonium lauryl sulfate provide sufficient basis for concluding that sodium cetearyl sulfate and related alkyl sulfates are safe in the practices of use and concentration described in the safety assessment.

Surface disinfection challenges for Candida auris: an in-vitro study.

PubMed

Kean, R; Sherry, L; Townsend, E; McKloud, E; Short, B; Akinbobola, A; Mackay, W G; Williams, C; Jones, B L; Ramage, G

2018-04-01

The emerging pathogenic multidrug-resistant yeast Candida auris is an important source of healthcare-associated infections and of growing global clinical concern. The ability of this organism to survive on surfaces and withstand environmental stressors creates a challenge for eradicating it from hospitals. A panel of C. auris clinical isolates was evaluated on different surface environments against the standard disinfectant sodium hypochlorite and high-level disinfectant peracetic acid. C. auris was shown to selectively tolerate clinically relevant concentrations of sodium hypochlorite and peracetic acid in a surface-dependent manner, which may explain its ability to successfully persist within the hospital environment. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Electrocardiographic Biomarkers for Detection of Drug-Induced Late Sodium Current Block

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vicente, Jose; Johannesen, Lars; Hosseini, Meisam

Drugs that prolong the heart rate corrected QT interval (QTc) on the electrocardiogram (ECG) by blocking the hERG potassium channel and also block inward currents (late sodium or L-type calcium) are not associated with torsade de pointes (e.g. ranolazine and verapamil). Furthermore, identifying ECG signs of late sodium current block could aid in the determination of proarrhythmic risk for new drugs. A new cardiac safety paradigm for drug development (the "CiPA" initiative) will involve the preclinical assessment of multiple human cardiac ion channels and ECG biomarkers are needed to determine if there are unexpected ion channel effects in humans.

Electrocardiographic Biomarkers for Detection of Drug-Induced Late Sodium Current Block

DOE PAGES

Vicente, Jose; Johannesen, Lars; Hosseini, Meisam; ...

2016-12-30

Drugs that prolong the heart rate corrected QT interval (QTc) on the electrocardiogram (ECG) by blocking the hERG potassium channel and also block inward currents (late sodium or L-type calcium) are not associated with torsade de pointes (e.g. ranolazine and verapamil). Furthermore, identifying ECG signs of late sodium current block could aid in the determination of proarrhythmic risk for new drugs. A new cardiac safety paradigm for drug development (the "CiPA" initiative) will involve the preclinical assessment of multiple human cardiac ion channels and ECG biomarkers are needed to determine if there are unexpected ion channel effects in humans.

An effective assessment of valproate sodium-induced hepatotoxicity with UPLC-MS and (1)HNMR-based metabonomics approach.

PubMed

Huo, Taoguang; Chen, Xi; Lu, Xiumei; Qu, Lianyue; Liu, Yang; Cai, Shuang

2014-10-15

Valproate sodium is one of the most prescribed antiepileptic drugs. However, valproate sodium has various side effects, especially its toxicity on liver. Current markers for toxicity reflect mostly the late stages of tissue damage; thus, more efficient methods for toxicity evaluation are desired. To evaluate the toxicity of valproate sodium on liver, we performed both UPLC-MS and (1)HNMR-based metabonomics analysis of serum samples from 34 epileptic patients (age: 42.0±18.6, 18 male/16 female) after valproate sodium treatment. Compared to conventional markers, the serum metabolic profiles provided clear distinction of the valproate sodium induced normal liver function and abnormal liver function in epileptic patients. Through multivariate statistical analysis, we identified marker metabolites associated with the hepatotoxicity induced by valproate sodium, such as glucose, lactate, acetoacetate, VLDL/LDL, lysophosphatidylcholines, phosphatidylcholines, choline, creatine, amino acids, N-acetyl glycoprotein, pyruvate and uric acid. This metabonomics approach may provide effective way to evaluate the valproate sodium-induced toxicity in a manner that can complement current measures. This approach is expected to find broader application in other drug-induced toxicity assessment. Copyright © 2014 Elsevier B.V. All rights reserved.

Sodium Reduction in Processed Foods in Brazil: Analysis of Food Categories and Voluntary Targets from 2011 to 2017

PubMed Central

Silva, Sara A.; L’Abbé, Mary; Jaime, Patricia C.

2017-01-01

Non-communicable diseases, including cardiovascular diseases, are responsible for over 70% of deaths in Brazil. Currently, over 25% of Brazilian adults are diagnosed as hypertensive; overall, current dietary sodium intake in Brazil (4700 mg/person) is over twice the international recommendations, and 70–90% of adolescents and adults consume excessive sodium. National sodium reduction strategies consider the main dietary sources of sodium to be added salt to foods, foods consumed outside of the household, and sodium in processed foods. The national voluntary strategy for sodium reduction in priority food categories has been continuously monitored over a 6-year period (2011–2017) and there was a significant 8–34% reduction in the average sodium content of over half food categories. Different food categories have undergone differing reductions in sodium over time, aiding gradual biannual targets to allow industries to develop new technologies and consumers to adapt to foods with less salt. By 2017, most products of all food categories had met the regional targets proposed by the Pan American Health Organization, showing that voluntary sodium reduction strategies can potentially contribute to food reformulation. Nevertheless, regulatory approaches may still be necessary in the future in order to reach all food producers and to allow stronger enforcement to meet more stringent regional targets. PMID:28704932

Stacked vapor fed amtec modules

DOEpatents

Sievers, Robert K.

1989-01-01

The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

Masking Vegetable Bitterness to Improve Palatability Depends on Vegetable Type and Taste Phenotype

PubMed Central

2013-01-01

Consumption of dark green vegetables falls short of recommendations, in part, because of unpleasant bitterness. A laboratory-based study of 37 adults was used to determine bitter and hedonic responses to vegetables (asparagus, Brussels sprouts, kale) with bitter masking agents (1.33 M sodium acetate, 10 and 32 mM sodium chloride, and 3.2 mM aspartame) and then characterized by taste phenotype and vegetable liking. In repeated-measures ANOVA, aspartame was most effective at suppressing bitterness and improving hedonic responses for all sampled vegetables. Among the sodium salts, 32 mM sodium chloride decreased bitterness for kale and sodium acetate reduced bitterness across all vegetables with a tendency to increase liking for Brussels sprouts, as release from mixture suppression increased perceived sweetness. Participants were nearly equally divided into three 6-n-propylthiouracil (PROP) phenotype groups. Those tasting the least PROP bitterness (non-tasters) reported least vegetable bitterness, and the additives produced little change in vegetable liking. Aspartame persisted as the most effective bitter blocker for the PROP tasters (medium, supertasters), improving vegetable liking for the medium tasters but too much sweetness for supertasters. The sodium salts showed some bitter blocking for PROP tasters, particularly sodium acetate, without significant gains in vegetable liking. Via a survey, adults characterized as low vegetable likers reported greater increase in vegetable liking with the maskers than did vegetable likers. These results suggest that bitter masking agents (mainly sweeteners) can suppress bitterness to increase acceptance if they are matched to perceived vegetable bitterness or to self-reported vegetable disliking. PMID:23682306

Mutant SOD1-expressing astrocytes release toxic factors that trigger motoneuron death by inducing hyperexcitability

PubMed Central

Fritz, Elsa; Izaurieta, Pamela; Weiss, Alexandra; Mir, Franco R.; Rojas, Patricio; Gonzalez, David; Rojas, Fabiola; Brown, Robert H.; Madrid, Rodolfo

2013-01-01

Amyotrophic lateral sclerosis (ALS) is a devastating paralytic disorder caused by dysfunction and degeneration of motoneurons starting in adulthood. Recent studies using cell or animal models document that astrocytes expressing disease-causing mutations of human superoxide dismutase 1 (hSOD1) contribute to the pathogenesis of ALS by releasing a neurotoxic factor(s). Neither the mechanism by which this neurotoxic factor induces motoneuron death nor its cellular site of action has been elucidated. Here we show that acute exposure of primary wild-type spinal cord cultures to conditioned medium derived from astrocytes expressing mutant SOD1 (ACM-hSOD1G93A) increases persistent sodium inward currents (PCNa), repetitive firing, and intracellular calcium transients, leading to specific motoneuron death days later. In contrast to TTX, which paradoxically increased twofold the amplitude of calcium transients and killed motoneurons, reduction of hyperexcitability by other specific (mexiletine) and nonspecific (spermidine and riluzole) blockers of voltage-sensitive sodium (Nav) channels restored basal calcium transients and prevented motoneuron death induced by ACM-hSOD1G93A. These findings suggest that riluzole, the only FDA-approved drug with known benefits for ALS patients, acts by inhibiting hyperexcitability. Together, our data document that a critical element mediating the non-cell-autonomous toxicity of ACM-hSOD1G93A on motoneurons is increased excitability, an observation with direct implications for therapy of ALS. PMID:23486205

First report on an inotropic peptide activating tetrodotoxin-sensitive, "neuronal" sodium currents in the heart.

PubMed

Kirchhof, Paulus; Tal, Tzachy; Fabritz, Larissa; Klimas, Jan; Nesher, Nir; Schulte, Jan S; Ehling, Petra; Kanyshkova, Tatayana; Budde, Thomas; Nikol, Sigrid; Fortmueller, Lisa; Stallmeyer, Birgit; Müller, Frank U; Schulze-Bahr, Eric; Schmitz, Wilhelm; Zlotkin, Eliahu; Kirchhefer, Uwe

2015-01-01

New therapeutic approaches to improve cardiac contractility without severe risk would improve the management of acute heart failure. Increasing systolic sodium influx can increase cardiac contractility, but most sodium channel activators have proarrhythmic effects that limit their clinical use. Here, we report the cardiac effects of a novel positive inotropic peptide isolated from the toxin of the Black Judean scorpion that activates neuronal tetrodotoxin-sensitive sodium channels. All venoms and peptides were isolated from Black Judean Scorpions (Buthotus Hottentotta) caught in the Judean Desert. The full scorpion venom increased left ventricular function in sedated mice in vivo, prolonged ventricular repolarization, and provoked ventricular arrhythmias. An inotropic peptide (BjIP) isolated from the full venom by chromatography increased cardiac contractility but did neither provoke ventricular arrhythmias nor prolong cardiac repolarization. BjIP increased intracellular calcium in ventricular cardiomyocytes and prolonged inactivation of the cardiac sodium current. Low concentrations of tetrodotoxin (200 nmol/L) abolished the effect of BjIP on calcium transients and sodium current. BjIP did not alter the function of Nav1.5, but selectively activated the brain-type sodium channels Nav1.6 or Nav1.3 in cellular electrophysiological recordings obtained from rodent thalamic slices. Nav1.3 (SCN3A) mRNA was detected in human and mouse heart tissue. Our pilot experiments suggest that selective activation of tetrodotoxin-sensitive neuronal sodium channels can safely increase cardiac contractility. As such, the peptide described here may become a lead compound for a new class of positive inotropic agents. © 2014 American Heart Association, Inc.

Sodium and calcium currents shape action potentials in immature mouse inner hair cells

PubMed Central

Marcotti, Walter; Johnson, Stuart L; Rüsch, Alfons; Kros, Corné J

2003-01-01

Before the onset of hearing at postnatal day 12, mouse inner hair cells (IHCs) produce spontaneous and evoked action potentials. These spikes are likely to induce neurotransmitter release onto auditory nerve fibres. Since immature IHCs express both α1D (Cav1.3) Ca2+ and Na+ currents that activate near the resting potential, we examined whether these two conductances are involved in shaping the action potentials. Both had extremely rapid activation kinetics, followed by fast and complete voltage-dependent inactivation for the Na+ current, and slower, partially Ca2+-dependent inactivation for the Ca2+ current. Only the Ca2+ current is necessary for spontaneous and induced action potentials, and 29 % of cells lacked a Na+ current. The Na+ current does, however, shorten the time to reach the action-potential threshold, whereas the Ca2+ current is mainly involved, together with the K+ currents, in determining the speed and size of the spikes. Both currents increased in size up to the end of the first postnatal week. After this, the Ca2+ current reduced to about 30 % of its maximum size and persisted in mature IHCs. The Na+ current was downregulated around the onset of hearing, when the spiking is also known to disappear. Although the Na+ current was observed as early as embryonic day 16.5, its role in action-potential generation was only evident from just after birth, when the resting membrane potential became sufficiently negative to remove a sizeable fraction of the inactivation (half inactivation was at −71 mV). The size of both currents was positively correlated with the developmental change in action-potential frequency. PMID:12937295

Second-messenger regulation of sodium transport in mammalian airway epithelia.

PubMed Central

Graham, A; Steel, D M; Alton, E W; Geddes, D M

1992-01-01

1. Sodium absorption is the dominant ion transport process in conducting airways and is a major factor regulating the composition of airway surface liquid. However, little is known about the control of airway sodium transport by intracellular regulatory pathways. 2. In sheep tracheae and human bronchi mounted in Ussing chambers under short circuit conditions, the sodium current can be isolated by pretreating tissues with acetazolamide (100 microM) to inhibit bicarbonate secretion, bumetanide (100 microM) to inhibit chloride secretion and phloridzin (200 microM) to inhibit sodium-glucose cotransport. This sodium current consists of amiloride-sensitive (57%) and amiloride-insensitive (43%) components. 3. The regulation of the isolated sodium current by three second messenger pathways was studied using the calcium ionophore A23187 to elevate intracellular calcium, a combination of forskolin and the phosphodiesterase inhibitor zardaverine to elevate intracellular cyclic AMP, and the phorbol ester 12,13-phorbol dibutyrate (PDB) to stimulate protein kinase C. 4. In sheep trachea, A23187 produces a dose-related inhibition of the sodium current with maximal effect (38% of ISC) at 10 microM and IC50 1 microM. This response affects both the amiloride-sensitive and insensitive components of the sodium current and is not altered by prior stimulation of protein kinase C or elevation of intracellular cyclic AMP. In human bronchi, A23187 (10 microM) produced a significantly greater inhibition of ISC (68%), a response which was unaffected by prior treatment with PDB or forskolin-zardaverine. 5. In sheep trachea, stimulation of protein kinase C with PDB produced a dose-related inhibition of ISC maximal (56% of ISC) at 50 nM (IC50 7 nM). This response was abolished by amiloride (100 microM) pretreatment suggesting a selective effect on the amiloride-sensitive component of the sodium current. The response was not altered by prior elevation of intracellular calcium or cyclic AMP. PDB (10 nM) caused a similar inhibition of ISC in human bronchi (43%). The effect of PKC stimulation following pretreatment with A23187 was diminished in human bronchi. Elevating intracellular cyclic AMP did not alter this response. 6. Addition of forskolin (1 microM) together with the phosphodiesterase inhibitor zardaverine (100 microM) produced a mean 35-fold increase in intracellular cyclic AMP in sheep trachea. This was associated with a small, but significant, 6% transient increase in ISC followed by a significant 4% fall. Neither effect could be abolished by amiloride pretreatment. In human bronchi, a small decrease in ISC which could not be distinguished from that occurring in controls was observed.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1464841

Metam sodium reduces viability and infectivity of Eimeria oocysts

USDA-ARS?s Scientific Manuscript database

Metam sodium (MS, sodium N-methyldithiocarbamate) is a widely used soil pesticide. Fumigation or chemical sterilization of poultry litter containing infectious oocysts could be an effective strategy to block the transmission of avian coccidia. In the current study the effect of MS on the viability ...

76 FR 17026 - New Animal Drugs; Arsanilate Sodium; Sulfaethoxypyridazine

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-28

... [Docket No. FDA-2011-N-0003] New Animal Drugs; Arsanilate Sodium; Sulfaethoxypyridazine AGENCY: Food and... Administration (FDA) is amending the animal drug regulations to remove sections pertaining to use of arsanilate sodium and sulfaethoxypyridazine in medicated feed because there are no currently approved new animal...

Intrinsic and integrative properties of substantia nigra pars reticulata neurons

PubMed Central

Zhou, Fu-Ming; Lee, Christian R.

2011-01-01

The GABA projection neurons of the substantia nigra pars reticulata (SNr) are output neurons for the basal ganglia and thus critical for movement control. Their most striking neurophysiological feature is sustained, spontaneous high frequency spike firing. A fundamental question is: what are the key ion channels supporting the remarkable firing capability in these neurons? Recent studies indicate that these neurons express tonically active TRPC3 channels that conduct a Na-dependent inward current even at hyperpolarized membrane potentials. When the membrane potential reaches −60 mV, a voltage-gated persistent sodium current (INaP) starts to activate, further depolarizing the membrane potential. At or slightly below −50 mV, the large transient voltage-activated sodium current (INaT) starts to activate and eventually triggers the rapid rising phase of action potentials. SNr GABA neurons have a higher density of (INaT), contributing to the faster rise and larger amplitude of action potentials, compared with the slow-spiking dopamine neurons. INaT also recovers from inactivation more quickly in SNr GABA neurons than in nigral dopamine neurons. In SNr GABA neurons, the rising phase of the action potential triggers the activation of high-threshold, inactivation-resistant Kv3-like channels that can rapidly repolarize the membrane. These intrinsic ion channels provide SNr GABA neurons with the ability to fire spontaneous and sustained high frequency spikes. Additionally, robust GABA inputs from direct pathway medium spiny neurons in the striatum and GABA neurons in the globus pallidus may inhibit and silence SNr GABA neurons, whereas glutamate synaptic input from the subthalamic nucleus may induce burst firing in SNr GABA neurons. Thus, afferent GABA and glutamate synaptic inputs sculpt the tonic high frequency firing of SNr GABA neurons and the consequent inhibition of their targets into an integrated motor control signal that is further fine-tuned by neuromodulators including dopamine, serotonin, endocannabinoids, and H2O2. PMID:21839148

Effects of Volatile Aromatic Anesthetics on Voltage-Gated Na+ Channels Expressed in Xenopus Oocytes

PubMed Central

Horishita, Takafumi; Eger, Edmond I; Harris, R. Adron

2008-01-01

Background Many inhaled anesthetics inhibit voltage-gated sodium channels at clinically relevant concentrations, and suppression of neurotransmitter release by these agents results, at least partly, from decreased presynaptic sodium channel activity. Volatile aromatic anesthetics can inhibit N-methyl-D-aspartate (NMDA) receptor function and enhance γ-amino butyric acid A (GABAA) receptor function, but these effects depend strongly on the chemical properties of the aromatic ompounds. The present study tested whether diverse aromatic anesthetics consistently inhibit sodium channel function. Methods We studied the effect of eight aromatic anesthetics on Nav1.2 sodium channels with β1 subunits, using whole-cell, two-electrode voltage-clamp techniques in Xenopus oocytes. Results All aromatic anesthetics inhibited INa (sodium currents) at a holding potential which produce half-maximal current (V1/2) (partial depolarization); inhibition was modest with 1,3,5-trifluorobenzene (8 ± 2%), pentafluorobenzene (13 ± 2%), and hexafluorobenzene (13 ± 2%), but greater with benzene (37 ± 2%), fluorobenzene (39 ± 2%), 1,2-difluorobenzene (48 ± 2%), 1,4-difluorobenzene (31 ± 3%), and 1,2,4-trifluorobenzene (33 ± 1%). Such dichotomous effects were noted by others for NMDA and GABAA receptors. Parallel, but much smaller inhibition, was found for INa at a holding potential which produced near maximal current (−90 mV) (VH-90), and hexafluorobenzene caused small (6 ± 1%) potentiation of this current. These changes in sodium channel function were correlated with effectiveness for inhibiting NMDA receptors, with lipid solubility of the compounds, with molecular volume, and with cation-π interactions. Conclusion Aromatic compounds vary in their actions on the kinetics of sodium channel gating and this may underlie their variable inhibition. The range of inhibition produced by MAC concentrations of inhaled anesthetics indicates that sodium channel inhibition may underlie the action of some of these anesthetics but not others. PMID:18931215

Reducing Sodium in Foods: The Effect on Flavor

PubMed Central

Liem, Djin Gie; Miremadi, Fatemeh; Keast, Russell S. J.

2011-01-01

Sodium is an essential micronutrient and, via salt taste, appetitive. High consumption of sodium is, however, related to negative health effects such as hypertension, cardiovascular diseases and stroke. In industrialized countries, about 75% of sodium in the diet comes from manufactured foods and foods eaten away from home. Reducing sodium in processed foods will be, however, challenging due to sodium’s specific functionality in terms of flavor and associated palatability of foods (i.e., increase of saltiness, reduction of bitterness, enhancement of sweetness and other congruent flavors). The current review discusses the sensory role of sodium in food, determinants of salt taste perception and a variety of strategies, such as sodium replacers (i.e., potassium salts) and gradual reduction of sodium, to decrease sodium in processed foods while maintaining palatability. PMID:22254117

Ion currents involved in oocyte maturation, fertilization and early developmental stages of the ascidian Ciona intestinalis.

PubMed

Tosti, Elisabetta; Gallo, Alessandra; Silvestre, Francesco

2011-01-01

Electrophysiological techniques were used to study the role of ion currents in the ascidian Ciona intestinalis oocyte plasma membrane during different stages of growth, meiosis, fertilization and early development. Three stages of immature oocytes were discriminated in the ovary, with the germinal vesicle showing specific different features of growth and maturation. Stage-A (pre-vitellogenic) oocytes exhibited the highest L-type calcium current activity and were incompetent for meiosis resumption. Stage-B (vitellogenic) oocytes showed a progressive disappearance of calcium currents and the first appearance of sodium currents that remained high during the maturation process, up to the post-vitellogenic stage-C oocytes. The latter had acquired meiotic competence, undergoing spontaneous in vitro maturation and interacting with the spermatozoon. However, fertilized oocytes did not produce normal larvae, suggesting that cytoplasmic maturation may affect embryo development. In mature oocytes at the metaphase I stage, sodium currents were present and remained high up to the zygote stage. Oocytes fertilized in the absence of sodium showed significant reduction of the fertilization current amplitude and high development of anomalous "rosette" embryos. Current amplitudes became negligible in embryos at the 2- and 4-cell stage, whereas resumption of all the current activities occurred at the 8-cell embryo. Taken together, these results suggest: (i) an involvement of L-type calcium currents in initial oocyte meiotic progression and growth; (ii) a role of sodium currents at fertilization; (iii) a role of the fertilization current in ensuring normal embryo development. Copyright © 2011 Wiley Periodicals, Inc.

The effect of intravenous lactated Ringer's solution versus 0.9% sodium chloride solution on serum osmolality in human volunteers.

PubMed

Williams, E L; Hildebrand, K L; McCormick, S A; Bedel, M J

1999-05-01

Animal studies have shown that large volumes of IV lactated Ringer's solution (LR) decrease serum osmolality, thereby increasing cerebral water. These studies have led to recommendations to limit LR to avoid cerebral edema in neurosurgical patients. Eighteen healthy human volunteers aged 20-48 yr received 50 mL/kg LR over 1 h on one occasion and 0.9% sodium chloride (NS) on another. Venous samples were taken at baseline (T1), at infusion end (T2), and 1 h after T2 (T3). Time until first urination was noted. With LR, serum osmolality decreased by 4+/-3 mOsm/kg from T1 to T2 and increased insignificantly with NS. At T3, osmolality returned almost to baseline in the LR group. Blood pH increased from T1 to T2 with LR by 0.04+/-0.04 and decreased with NS by 0.04+/-0.04. These pH changes persisted at T3. Subjective mental changes occurred only with NS. Abdominal discomfort was more common with NS. Time until first urination was longer with NS (106+/-11 min) than with LR (75+/-10 min) (P < 0.001). In healthy humans, an infusion of large volumes of LR, but not NS, transiently decreased serum osmolality, whereas acidosis associated with NS persisted and urinary output was slower with NS. Large volumes of lactated Ringer's solution administered to healthy humans produced small transient changes in serum osmolality. Large volumes of sodium chloride did not change osmolality but resulted in lower pH.

Glial cells have heart: rH1 Na+ channel mRNA and protein in spinal cord astrocytes.

PubMed

Black, J A; Dib-Hajj, S; Cohen, S; Hinson, A W; Waxman, S G

1998-07-01

Astrocytes in vitro express several distinct voltage-sensitive sodium currents, including tetrodotoxin (TTX)-resistant in non-stellate astrocytes and TTX-sensitive currents in stellate astrocytes. However, the molecular identity of the underlying channels, and the mechanisms that regulate their expression, have yet to be identified. Since spinal cord astrocytes in vitro express sodium currents that are nearly ten-fold greater that those of astrocytes derived from other regions, we used reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization, and immunocytochemistry to search for a sodium channel mRNA and protein corresponding to a TTX-resistant channel in these cells. RT-PCR did not detect transcripts for SNS, which is known to encode a TTX-resistant current in dorsal root ganglion neurons. However, RT-PCR demonstrated the presence of rH1 mRNA in cultured spinal cord astrocytes derived from postnatal day 0 (P0) Sprague Dawley rats at 7 days in vitro and in also intact spinal cords of P0 and P7 rats. Hybridization signal for rH1 mRNA was detected by in situ hybridization cytochemistry in most non-stellate and, at varying levels, in stellate astrocytes in these cultures. Immunocytochemical studies, utilizing a polyclonal antibody (R-12) generated against a conserved polypeptide sequence of sodium channels, demonstrated sodium channel immunoreactivity in non-stellate and stellate astrocytes in these cultures. Spinal cord cultures reacted with a rH1-specific polyclonal antibody also showed rH1 immunostaining in non-stellate and stellate astrocytes, although the intensity of the rH1 immunoreactivity in both astrocyte morphologies was attenuated compared to that observed with the R-12 generic sodium channel antibody. The presence of rH1 mRNA and protein in non-stellate astrocytes in vitro provides a possible correlate for the TTX-resistant current that has been recorded in these cells. Since TTX-resistant current is not present in stellate astrocytes, the presence of rH1 mRNA and protein in these cells suggests, in addition, that post-translational mechanisms participate in the control of sodium channel expression in these cells.

Assessing U.S. sodium intake through dietary data and urine biomarkers

USDA-ARS?s Scientific Manuscript database

Sodium intake is directly related to blood pressure, a primary risk factor for heart disease and stroke. Reducing intake is estimated to save billions in U.S. health care dollars annually. Current public health recommendations and efforts targeting sodium reductions make accurate monitoring of pop...

Activation of β-noradrenergic receptors enhances rhythmic bursting in mouse olfactory bulb external tufted cells.

PubMed

Zhou, Fu-Wen; Dong, Hong-Wei; Ennis, Matthew

2016-12-01

The main olfactory bulb (MOB) receives a rich noradrenergic innervation from the nucleus locus coeruleus. Despite the well-documented role of norepinephrine and β-adrenergic receptors in neonatal odor preference learning, identified cellular physiological actions of β-receptors in the MOB have remained elusive. β-Receptors are expressed at relatively high levels in the MOB glomeruli, the location of external tufted (ET) cells that exert an excitatory drive on mitral and other cell types. The present study investigated the effects of β-receptor activation on the excitability of ET cells with patch-clamp electrophysiology in mature mouse MOB slices. Isoproterenol and selective β 2 -, but not β 1 -, receptor agonists were found to enhance two key intrinsic currents involved in ET burst initiation: persistent sodium (I NaP ) and hyperpolarization-activated inward (I h ) currents. Together, the positive modulation of these currents increased the frequency and strength of ET cell rhythmic bursting. Rodent sniff frequency and locus coeruleus neuronal firing increase in response to novel stimuli or environments. The increase in ET excitability by β-receptor activation may better enable ET cell rhythmic bursting, and hence glomerular network activity, to pace faster sniff rates during heightened norepinephrine release associated with arousal. Copyright © 2016 the American Physiological Society.

Electronic States and Persistent Currents in Nanowire Quantum Ring

NASA Astrophysics Data System (ADS)

Kokurin, I. A.

2018-04-01

The new model of a quantum ring (QR) defined inside a nanowire (NW) is proposed. The one-particle Hamiltonian for electron in [111]-oriented NW QR is constructed taking into account both Rashba and Dresselhaus spin-orbit coupling (SOC). The energy levels as a function of magnetic field are found using the exact numerical diagonalization. The persistent currents (both charge and spin) are calculated. The specificity of SOC and arising anticrossings in energy spectrum lead to unusual features in persistent current behavior. The variation of magnetic field or carrier concentration by means of gate can lead to pure spin persistent current with the charge current being zero.

Sodium and potassium conductance changes during a membrane action potential.

PubMed

Bezanilla, F; Rojas, E; Taylor, R E

1970-12-01

1. A method for turning a membrane potential control system on and off in less than 10 musec is described. This method was used to record membrane currents in perfused giant axons from Dosidicus gigas and Loligo forbesi after turning on the voltage clamp system at various times during the course of a membrane action potential.2. The membrane current measured just after the capacity charging transient was found to have an almost linear relation to the controlled membrane potential.3. The total membrane conductance taken from these current-voltage curves was found to have a time course during the action potential similar to that found by Cole & Curtis (1939).4. The instantaneous current voltage curves were linear enough to make it possible to obtain a good estimate of the individual sodium and potassium channel conductances, either algebraically or by clamping to the sodium, or potassium, reversal potentials. Good general agreement was obtained with the predictions of the Hodgkin-Huxley equations.5. We consider these results to constitute the first direct experimental demonstration of the conductance changes to sodium and potassium during the course of an action potential.

Sodium modified molybdenum sulfide via molten salt electrolysis as an anode material for high performance sodium-ion batteries.

PubMed

Wang, Shuai; Tu, Jiguo; Yuan, Yan; Ma, Rui; Jiao, Shuqiang

2016-01-28

The paper reports a facile and cost effective method for fabricating sodium molybdenum sulfide nanoparticles through using MoS2 sheets as the precursor by sodium-modification. The electrochemical performances of sodium molybdenum sulfide nanoparticles are studied as anode materials for sodium-ion batteries. The galvanostatic charge-discharge measurements have been performed in a voltage range of 0.01-2.6 V vs. Na(+)/Na under different current densities, using the as-prepared sodium molybdenum sulfide nanoparticles as a working electrode. Typically, the initial discharge and charge capacities of sodium molybdenum sulfide nanoparticles are 475 and 380 mA h g(-1), respectively, at a current density of 20 mA g(-1). The sodium molybdenum sulfide nanoparticles exhibit high capacity with a reversible discharge capacity of about 190 mA h g(-1) after 100 cycles. It should be emphasized that the discharge reaction consists of two steps which correspond to voltage plateaus of 0.93 V and 0.85 V vs. Na(+)/Na in the first discharge curve of the Na/MoS2 battery, respectively. But there is only one apparent voltage plateau in the Na/Na-Mo-S battery, and it reduces to below 0.5 V vs. Na(+)/Na, which can enhance the power density. All of the findings demonstrate that sodium molybdenum sulfide nanoparticles have steady cycling performance and environmental and cost friendliness as next generation secondary batteries.

Phenomenological studies on sodium for CSP applications: A safety review

NASA Astrophysics Data System (ADS)

Armijo, Kenneth M.; Andraka, Charles E.

2016-05-01

Sodium Heat transfer fluids (HTF) such as sodium, can achieve temperatures above 700°C to obtain power cycle performance improvements for reducing large infrastructure costs of high-temperature systems. Current concentrating solar power (CSP) sensible HTF's (e.g. air, salts) have poor thermal conductivity, and thus low heat transfer capabilities, requiring a large receiver. The high thermal conductivity of sodium has demonstrated high heat transfer rates on dish and towers systems, which allow a reduction in receiver area by a factor of two to four, reducing re-radiation and convection losses and cost by a similar factor. Sodium produces saturated vapor at pressures suitable for transport starting at 600°C and reaches one atmosphere at 870°C, providing a wide range of suitable operating conditions that match proposed high temperature, isothermal power cycles. This advantage could increase the efficiency while lowering the cost of CSP tower systems. Although there are a number of desirable thermal performance advantages associated with sensible sodium, its propensity to rapidly oxidize presents safety challenges. This investigation presents a literature review that captures historical operations/handling lessons for advanced sodium receiver designs, and the current state-of-knowledge related to sodium combustion behavior. Technical and operational solutions addressing sodium safety and applications in CSP will be discussed, including unique safety hazards and advantages using latent sodium. Lessons obtained from the nuclear industry with sensible and latent systems will also be discussed in the context of safety challenges and risk mitigation solutions.

Continuous subcutaneous infusion of lidocaine for persistent hiccup in advanced cancer.

PubMed

Kaneishi, Keisuke; Kawabata, Masahiro

2013-03-01

Persistent hiccup can cause anorexia, weight loss, disabling sleep deprivation, anxiety, and depression. Therefore, relief of persistent hiccup is important for advanced cancer patients and their family. Most reports on this condition are case series reports advocating the use of baclofen, haloperidol, gabapentin, and midazolam. However, these medications are occasionally ineffective or accompanied by intolerable side effects. The sodium channel blocker lidocaine has been shown to be effective in treating a variety of disorders thought to involve neuropathic mechanisms. Intravenous administration of lidocaine is common but efficacy has also been reported for subcutaneous infusion. In advanced cancer patients, subcutaneous infusion is easy, advantageous, and accompanied by less discomfort. We report a case of severe and sustained hiccup caused by gastric cancer that was successfully treated with a continuous subcutaneous infusion of lidocaine (480 mg (24 ml)/day) without severe side effects.

Stakeholder discussion to reduce population-wide sodium intake and decrease sodium in the food supply: a conference report from the American Heart Association Sodium Conference 2013 Planning Group.

PubMed

Antman, Elliott M; Appel, Lawrence J; Balentine, Douglas; Johnson, Rachel K; Steffen, Lyn M; Miller, Emily Ann; Pappas, Antigoni; Stitzel, Kimberly F; Vafiadis, Dorothea K; Whitsel, Laurie

2014-06-24

A 2-day interactive forum was convened to discuss the current status and future implications of reducing sodium in the food supply and to identify opportunities for stakeholder collaboration. Participants included 128 stakeholders engaged in food research and development, food manufacturing and retail, restaurant and food service operations, regulatory and legislative activities, public health initiatives, healthcare, academia and scientific research, and data monitoring and surveillance. Presentation topics included scientific evidence for sodium reduction and public health policy recommendations; consumer sodium intakes, attitudes, and behaviors; food technologies and solutions for sodium reduction and sensory implications; experiences of the food and dining industries; and translation and implementation of sodium intake recommendations. Facilitated breakout sessions were conducted to allow for sharing of current practices, insights, and expertise. A well-established body of scientific research shows that there is a strong relationship between excess sodium intake and high blood pressure and other adverse health outcomes. With Americans getting >75% of their sodium from processed and restaurant food, this evidence creates mounting pressure for less sodium in the food supply. The reduction of sodium in the food supply is a complex issue that involves multiple stakeholders. The success of new technological approaches for reducing sodium will depend on product availability, health effects (both intended and unintended), research and development investments, quality and taste of reformulated foods, supply chain management, operational modifications, consumer acceptance, and cost. The conference facilitated an exchange of ideas and set the stage for potential collaboration opportunities among stakeholders with mutual interest in reducing sodium in the food supply and in Americans' diets. Population-wide sodium reduction remains a critically important component of public health efforts to promote cardiovascular health and prevent cardiovascular disease and will remain a priority for the American Heart Association. © 2014 American Heart Association, Inc.

Ammonia toxicity and its prevention in inherited defects of the urea cycle.

PubMed

Walker, V

2009-09-01

The urea cycle is the final pathway for removal of surplus nitrogen from the body, and the major route in humans for detoxification of ammonia. The full complement of enzymes is expressed only in liver. Inherited deficiencies of urea cycle enzymes lead to hyperammonaemia, which causes brain damage. Severe defects present with hyperammonaemic crises in neonates. Equally devastating episodes may occur in previously asymptomatic adults with mild defects, most often X-linked ornithine transcarbamylase (OTC) deficiency. Several mechanisms probably contribute to pathogenesis. Treatment aims to reduce plasma ammonia quickly, reduce production of waste nitrogen, dispose of waste nitrogen using alternative pathways to the urea cycle and replace arginine. These therapies have increased survival and probably improve the neurological outcome. Arginine, sodium benzoate, sodium phenylbutyrate and, less often, sodium phenylacetate are used. Long-term correction is achieved by liver transplantation. Gene therapy for OTC deficiency is effective in animals, and work is ongoing to improve persistence and safety.

Dietary Sodium and Blood Pressure: How Low Should We Go?

PubMed

Van Horn, Linda

2015-01-01

Sodium intake in the United States exceeds recommended amounts across all age, gender and ethnic groups. National dietary guidelines advocate reduced intake by at least 1,000mg per day or more, but whether there is population-wide benefit from further reductions to levels of 1500mg per day remains controversial. A brief review of current evidence-based dietary guidelines is provided and key prospective, randomized studies that report dietary and urinary sodium data are summarized. Dietary sources of sodium and eating patterns that offer nutritiously sound approaches to nutrient dense, reduced sodium intake are compared. No studies suggest that high sodium intake at the levels of the population's current diet is optimal. On the contrary, national and international evidence and systematic reviews consistently recommend reducing sodium intake overall, generally by 1000mg/day. Recommendations to reduce intakes to 2400mg/d are generally accepted as beneficial. Whether further reductions to 1500mg/d are useful, feasible and safe among specific subgroups in the population who are at increased risk of hypertension or stroke remains controversial and requires individualized consideration by patients and their health care providers. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of a behavioral intervention that emphasizes spices and herbs on adherence to recommended sodium intake: results of the SPICE randomized clinical trial.

PubMed

Anderson, Cheryl A M; Cobb, Laura K; Miller, Edgar R; Woodward, Mark; Hottenstein, Annette; Chang, Alex R; Mongraw-Chaffin, Morgana; White, Karen; Charleston, Jeanne; Tanaka, Toshiko; Thomas, Letitia; Appel, Lawrence J

2015-09-01

For decades, dietary sodium intake in the United States has remained high, and few studies have examined strategies for maintaining recommended intakes. We examined the effects of a behavioral intervention, which emphasized spices and herbs, on the maintenance of sodium intake at the recommended intake of 1500 mg/d in individuals to whom the US Dietary Guidelines for Americans apply. We conducted a 2-phase study that included adults ≥18 y of age for whom Dietary Guidelines for Americans recommends 1500 mg Na/d. The study was conducted in Baltimore, Maryland, from 2012 to 2014. In phase 1, 55 individuals consumed a low-sodium diet for 4 wk. Participants were provided all foods, snacks, and calorie-containing drinks. In phase 2, 40 participants from phase 1 were randomly assigned to either a behavioral intervention to reduce sodium intake (n = 20) or a self-directed control group (n = 20) for 20 wk. The primary study outcome was the change in mean 24-h urinary sodium excretion during phase 2. Linear regression analyses were used to determine intervention effects on urinary sodium excretion. Participant characteristics were as follows: women: 65%; African American: 88%; hypertension: 63%; diabetes: 18%; mean age: 61 y; and mean body mass index (in kg/m(2)): 30. At the end of phase 2, mean 24-h sodium excretion was lower in the behavioral intervention than in the self-directed group (mean difference: -956.8 mg/d; 95% CI: -1538.7, -374.9 mg/d) after sodium intake at screening was controlled for (P = 0.002). These findings persisted in sensitivity analyses that excluded potentially incomplete urine collections [Mage's equation mean difference: -1090 mg/d (P = 0.001); Joosens' equation mean difference: -796 mg/d (P = 0.04)]. A multifactorial behavioral intervention emphasizing spices and herbs significantly reduced sodium intake. Because of the ubiquity of sodium in the US food supply, multilevel strategies addressing individual behaviors and the food supply are needed to improve adherence to recommendations. This trial was registered at clinicaltrials.gov as NCT01615159. © 2015 American Society for Nutrition.

The Effect of Serum Sodium on Survival in Patients Treated by Peritoneal Dialysis in the United Kingdom.

PubMed

Al-Chidadi, Asmaa; Nitsch, Dorothea; Davenport, Andrew

♦ BACKGROUND: Studies in hemodialysis patients suggest that hyponatremia is associated with increased mortality. However, results from peritoneal dialysis (PD) patients are discordant. We wished to establish whether there was an association between serum sodium and mortality risk in PD patients. ♦ METHODS: We analyzed 3,108 PD patients enrolled at day 90 of renal replacement therapy (RRT) into the UK Renal Registry (UKRR) data base with available serum sodium measurements (in 3 groups: ≤ 137, 138 - 140, ≥ 141 mmol/L) who were then followed up until death or the censoring date (31 December 2012). Analysis used Cox-regression with adjustment for age, sex, year of starting RRT, primary renal disease, serum albumin, smoking, and comorbidities. ♦ RESULTS: Unadjusted mortality rates were 118.6/1,000 person-years (py), 83.4/1,000 py, and 83.5/1,000 py for the lowest, middle, and highest serum sodium tertiles, respectively. After adjustment for covariates, patients in the lowest serum sodium group had almost 50% increased risk of dying compared with those with the highest serum sodium (hazard ratio [HR] 1.49, confidence interval [CI]:1.28 - 1.74), with a graded association between serum sodium and mortality. The association of serum sodium with mortality varied by age (p interaction < 0.001), and whilst this association attenuated after adjustment for confounding variables in the older age groups (55 - 64, and > 65 years), it remained in the younger age group of 18 - 54 years (HR 2.24 [1.36 - 3.70] in the lowest compared with the highest sodium tertile). ♦ CONCLUSIONS: Lower serum sodium concentrations at the start of RRT in PD patients are associated with increased risk of mortality. Whilst this association may well be due to confounding in the older age groups, the persistent strong association between hyponatremia and mortality in the younger age group after adjustment for the available confounders suggests that prospective studies are required to assess whether active intervention to maintain serum sodium changes outcomes. Copyright © 2017 International Society for Peritoneal Dialysis.

Validation of Finite-Element Models of Persistent-Current Effects in Nb 3Sn Accelerator Magnets

DOE PAGES

Wang, X.; Ambrosio, G.; Chlachidze, G.; ...

2015-01-06

Persistent magnetization currents are induced in superconducting filaments during the current ramping in magnets. The resulting perturbation to the design magnetic field leads to field quality degradation, in particular at low field where the effect is stronger relative to the main field. The effects observed in NbTi accelerator magnets were reproduced well with the critical-state model. However, this approach becomes less accurate for the calculation of the persistent-current effects observed in Nb 3Sn accelerator magnets. Here a finite-element method based on the measured strand magnetization is validated against three state-of-art Nb3Sn accelerator magnets featuring different subelement diameters, critical currents, magnetmore » designs and measurement temperatures. The temperature dependence of the persistent-current effects is reproduced. Based on the validated model, the impact of conductor design on the persistent current effects is discussed. The performance, limitations and possible improvements of the approach are also discussed.« less

Using Benchmarking To Strengthen the Assessment of Persistence.

PubMed

McLachlan, Michael S; Zou, Hongyan; Gouin, Todd

2017-01-03

Chemical persistence is a key property for assessing chemical risk and chemical hazard. Current methods for evaluating persistence are based on laboratory tests. The relationship between the laboratory based estimates and persistence in the environment is often unclear, in which case the current methods for evaluating persistence can be questioned. Chemical benchmarking opens new possibilities to measure persistence in the field. In this paper we explore how the benchmarking approach can be applied in both the laboratory and the field to deepen our understanding of chemical persistence in the environment and create a firmer scientific basis for laboratory to field extrapolation of persistence test results.

Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water

PubMed Central

Gallandat, Karin; Daniels, Kyle; Desmarais, Anne Marie; Scheinman, Pamela; Lantagne, Daniele

2017-01-01

To prevent Ebola transmission, frequent handwashing is recommended in Ebola Treatment Units and communities. However, little is known about which handwashing protocol is most efficacious. We evaluated six handwashing protocols (soap and water, alcohol-based hand sanitizer (ABHS), and 0.05% sodium dichloroisocyanurate, high-test hypochlorite, and stabilized and non-stabilized sodium hypochlorite solutions) for 1) efficacy of handwashing on the removal and inactivation of non-pathogenic model organisms and, 2) persistence of organisms in rinse water. Model organisms E. coli and bacteriophage Phi6 were used to evaluate handwashing with and without organic load added to simulate bodily fluids. Hands were inoculated with test organisms, washed, and rinsed using a glove juice method to retrieve remaining organisms. Impact was estimated by comparing the log reduction in organisms after handwashing to the log reduction without handwashing. Rinse water was collected to test for persistence of organisms. Handwashing resulted in a 1.94–3.01 log reduction in E. coli concentration without, and 2.18–3.34 with, soil load; and a 2.44–3.06 log reduction in Phi6 without, and 2.71–3.69 with, soil load. HTH performed most consistently well, with significantly greater log reductions than other handwashing protocols in three models. However, the magnitude of handwashing efficacy differences was small, suggesting protocols are similarly efficacious. Rinse water demonstrated a 0.28–4.77 log reduction in remaining E. coli without, and 0.21–4.49 with, soil load and a 1.26–2.02 log reduction in Phi6 without, and 1.30–2.20 with, soil load. Chlorine resulted in significantly less persistence of E. coli in both conditions and Phi6 without soil load in rinse water (p<0.001). Thus, chlorine-based methods may offer a benefit of reducing persistence in rinse water. We recommend responders use the most practical handwashing method to ensure hand hygiene in Ebola contexts, considering the potential benefit of chlorine-based methods in rinse water persistence. PMID:28231311

Fast-slow asymptotics for a Markov chain model of fast sodium current

NASA Astrophysics Data System (ADS)

Starý, Tomáš; Biktashev, Vadim N.

2017-09-01

We explore the feasibility of using fast-slow asymptotics to eliminate the computational stiffness of discrete-state, continuous-time deterministic Markov chain models of ionic channels underlying cardiac excitability. We focus on a Markov chain model of fast sodium current, and investigate its asymptotic behaviour with respect to small parameters identified in different ways.

Distribution of TTX-sensitive voltage-gated sodium channels in primary sensory endings of mammalian muscle spindles.

PubMed

Carrasco, Dario I; Vincent, Jacob A; Cope, Timothy C

2017-04-01

Knowledge of the molecular mechanisms underlying signaling of mechanical stimuli by muscle spindles remains incomplete. In particular, the ionic conductances that sustain tonic firing during static muscle stretch are unknown. We hypothesized that tonic firing by spindle afferents depends on sodium persistent inward current (INaP) and tested for the necessary presence of the appropriate voltage-gated sodium (NaV) channels in primary sensory endings. The NaV 1.6 isoform was selected for both its capacity to produce INaP and for its presence in other mechanosensors that fire tonically. The present study shows that NaV 1.6 immunoreactivity (IR) is concentrated in heminodes, presumably where tonic firing is generated, and we were surprised to find NaV 1.6 IR strongly expressed also in the sensory terminals, where mechanotransduction occurs. This spatial pattern of NaV 1.6 IR distribution was consistent for three mammalian species (rat, cat, and mouse), as was tonic firing by primary spindle afferents. These findings meet some of the conditions needed to establish participation of INaP in tonic firing by primary sensory endings. The study was extended to two additional NaV isoforms, selected for their sensitivity to TTX, excluding TTX-resistant NaV channels, which alone are insufficient to support firing by primary spindle endings. Positive immunoreactivity was found for NaV 1.1 , predominantly in sensory terminals together with NaV 1.6 and for NaV 1.7 , mainly in preterminal axons. Differential distribution in primary sensory endings suggests specialized roles for these three NaV isoforms in the process of mechanosensory signaling by muscle spindles. NEW & NOTEWORTHY The molecular mechanisms underlying mechanosensory signaling responsible for proprioceptive functions are not completely elucidated. This study provides the first evidence that voltage-gated sodium channels (NaVs) are expressed in the spindle primary sensory ending, where NaVs are found at every site involved in transduction or encoding of muscle stretch. We propose that NaVs contribute to multiple steps in sensory signaling by muscle spindles as it does in other types of slowly adapting sensory neurons. Copyright © 2017 the American Physiological Society.

Inherited pain: sodium channel Nav1.7 A1632T mutation causes erythromelalgia due to a shift of fast inactivation.

PubMed

Eberhardt, Mirjam; Nakajima, Julika; Klinger, Alexandra B; Neacsu, Cristian; Hühne, Kathrin; O'Reilly, Andrias O; Kist, Andreas M; Lampe, Anne K; Fischer, Kerstin; Gibson, Jane; Nau, Carla; Winterpacht, Andreas; Lampert, Angelika

2014-01-24

Inherited erythromelalgia (IEM) causes debilitating episodic neuropathic pain characterized by burning in the extremities. Inherited "paroxysmal extreme pain disorder" (PEPD) differs in its clinical picture and affects proximal body areas like the rectal, ocular, or jaw regions. Both pain syndromes have been linked to mutations in the voltage-gated sodium channel Nav1.7. Electrophysiological characterization shows that IEM-causing mutations generally enhance activation, whereas mutations leading to PEPD alter fast inactivation. Previously, an A1632E mutation of a patient with overlapping symptoms of IEM and PEPD was reported (Estacion, M., Dib-Hajj, S. D., Benke, P. J., Te Morsche, R. H., Eastman, E. M., Macala, L. J., Drenth, J. P., and Waxman, S. G. (2008) NaV1.7 Gain-of-function mutations as a continuum. A1632E displays physiological changes associated with erythromelalgia and paroxysmal extreme pain disorder mutations and produces symptoms of both disorders. J. Neurosci. 28, 11079-11088), displaying a shift of both activation and fast inactivation. Here, we characterize a new mutation of Nav1.7, A1632T, found in a patient suffering from IEM. Although transfection of A1632T in sensory neurons resulted in hyperexcitability and spontaneous firing of dorsal root ganglia (DRG) neurons, whole-cell patch clamp of transfected HEK cells revealed that Nav1.7 activation was unaltered by the A1632T mutation but that steady-state fast inactivation was shifted to more depolarized potentials. This is a characteristic normally attributed to PEPD-causing mutations. In contrast to the IEM/PEPD crossover mutation A1632E, A1632T failed to slow current decay (i.e. open-state inactivation) and did not increase resurgent currents, which have been suggested to contribute to high-frequency firing in physiological and pathological conditions. Reduced fast inactivation without increased resurgent currents induces symptoms of IEM, not PEPD, in the new Nav1.7 mutation, A1632T. Therefore, persistent and resurgent currents are likely to determine whether a mutation in Nav1.7 leads to IEM or PEPD.

S(+)amphetamine induces a persistent leak in the human dopamine transporter: molecular stent hypothesis

PubMed Central

Rodriguez-Menchaca, Aldo A; Solis Jr, Ernesto; Cameron, Krasnodara; De Felice, Louis J

2012-01-01

BACKGROUND AND PURPOSE Wherever they are located, dopamine transporters (DATs) clear dopamine (DA) from the extracellular milieu to help regulate dopaminergic signalling. Exposure to amphetamine (AMPH) increases extracellular DA in the synaptic cleft, which has been ascribed to DAT reverse transport. Increased extracellular DA prolongs postsynaptic activity and reinforces abuse and hedonic behaviour. EXPERIMENTAL APPROACH Xenopus laevis oocytes expressing human (h) DAT were voltage-clamped and exposed to DA, R(-)AMPH, or S(+)AMPH. KEY RESULTS At -60mV, near neuronal resting potentials, S(+)AMPH induced a depolarizing current through hDAT, which after removing the drug, persisted for more than 30 min. This persistent leak in the absence of S(+)AMPH was in contrast to the currents induced by R(-)AMPH and DA, which returned to baseline immediately after their removal. Our data suggest that S(+)AMPH and Na+ carry the initial S(+)AMPH-induced current, whereas Na+ and Cl- carry the persistent leak current. We propose that the persistent current results from the internal action of S(+)AMPH on hDAT because the temporal effect was consistent with S(+)AMPH influx, and intracellular S(+)AMPH activated the effect. The persistent current was dependent on Na+ and was blocked by cocaine. Intracellular injection of S(+)AMPH also activated a DA-induced persistent leak current. CONCLUSIONS AND IMPLICATIONS We report a hitherto unknown action of S(+)AMPH on hDAT that potentially affects AMPH-induced DA release. We propose that internal S(+)AMPH acts as a molecular stent that holds the transporter open even after external S(+)AMPH is removed. Amphetamine-induced persistent leak currents are likely to influence dopaminergic signalling, DA release mechanisms, and amphetamine abuse. PMID:22014068

Contribution of near-threshold currents to intrinsic oscillatory activity in rat medial entorhinal cortex layer II stellate cells

PubMed Central

Boehlen, Anne; Henneberger, Christian; Erchova, Irina

2013-01-01

The temporal lobe is well known for its oscillatory activity associated with exploration, navigation, and learning. Intrinsic membrane potential oscillations (MPOs) and resonance of stellate cells (SCs) in layer II of the entorhinal cortex are thought to contribute to network oscillations and thereby to the encoding of spatial information. Generation of both MPOs and resonance relies on the expression of specific voltage-dependent ion currents such as the hyperpolarization-activated cation current (IH), the persistent sodium current (INaP), and the noninactivating muscarine-modulated potassium current (IM). However, the differential contributions of these currents remain a matter of debate. We therefore examined how they modify neuronal excitability near threshold and generation of near-threshold MPOs and resonance in vitro. We found that resonance mainly relied on IH and was reduced by IH blockers and modulated by cAMP and an IM enhancer but that neither of the currents exhibited full control over MPOs in these cells. As previously reported, IH controlled a theta-frequency component of MPOs such that blockade of IH resulted in fewer regular oscillations that retained low-frequency components and high peak amplitude. However, pharmacological inhibition and augmentation of IM also affected MPO frequencies and amplitudes. In contrast to other cell types, inhibition of INaP did not result in suppression of MPOs but only in a moderation of their properties. We reproduced the experimentally observed effects in a single-compartment stochastic model of SCs, providing further insight into the interactions between different ionic conductances. PMID:23076110

Epigenetic Histone Deacetylation Inhibition Prevents the Development and Persistence of Temporal Lobe Epilepsy.

PubMed

Reddy, Sandesh D; Clossen, Bryan L; Reddy, Doodipala Samba

2018-01-01

Epilepsy is a chronic brain disease characterized by repeated unprovoked seizures. Currently, no drug therapy exists for curing epilepsy or disease modification in people at risk. Despite several emerging mechanisms, there have been few studies of epigenetic signaling in epileptogenesis, the process whereby a normal brain becomes progressively epileptic because of precipitating factors. Here, we report a novel role of histone deacetylation as a critical epigenetic mechanism in epileptogenesis. Experiments were conducted using the histone deacetylase (HDAC) inhibitor sodium butyrate in the hippocampus kindling model of temporal lobe epilepsy (TLE), a classic model heavily used to approve drugs for treatment of epilepsy. Daily treatment with butyrate significantly inhibited HDAC activity and retarded the development of limbic epileptogenesis without affecting after-discharge signal. HDAC inhibition markedly impaired the persistence of seizure expression many weeks after epilepsy development. Moreover, subchronic HDAC inhibition for 2 weeks resulted in a striking retardation of epileptogenesis. HDAC inhibition, unexpectedly, also showed erasure of the epileptogenic state in epileptic animals. Finally, butyrate-treated animals exhibited a powerful reduction in mossy fiber sprouting, a morphologic index of epileptogenesis. Together these results underscore that HDAC inhibition prevents the development of TLE, indicating HDAC's critical signaling role in epileptogenesis. These findings, therefore, envisage a unique novel therapy for preventing or curing epilepsy by targeting the epigenetic HDAC pathway. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

From laboratory to environmental conditions: a new approach for chemical's biodegradability assessment.

PubMed

François, Brillet; Armand, Maul; Marie-José, Durand; Thouand, Gérald

2016-09-01

With thousands of organic chemicals released every day into our environment, Europe and other continents are confronted with increased risk of health and environmental problems. Even if a strict regulation such as REgistration, Authorization and restriction of CHemicals (REACH) is imposed and followed by industry to ensure that they prove the harmlessness of their substances, not all testing procedures are designed to cope with the complexity of the environment. This is especially true for the evaluation of persistence through biodegradability assessment guidelines. Our new approach has been to adapt "in the lab" biodegradability assessment to the environmental conditions and model the probability for a biodegradation test to be positive in the form of a logistic function of both the temperature and the viable cell density. Here, a proof of this new concept is proposed with the establishment of tri-dimensional biodegradability profiles of six chemicals (sodium benzoate, 4-nitrophenol, diethylene glycol, 2,4,5-trichlorophenol, atrazine, and glyphosate) between 4 to 30 °C and 10(4) to 10(8) cells ml(-1) as can be found in environmental compartments in time and space. The results show a significant increase of the predictive power of existing screening lab-scale tests designed for soluble substances. This strategy can be complementary to those current testing strategies with the creation of new indicators to quantify environmental persistence using lab-scale tests.

Sodium intake among U.S. school-age children: National Health and Nutrition Examination Survey, 2011-2012

USDA-ARS?s Scientific Manuscript database

Identifying current major dietary sources of sodium can enhance strategies to reduce excess sodium intake which occurs among 90% of U.S. school-aged children. We conducted a cross-sectional analysis of 24-hour dietary recall data from a nationally representative sample of 2,142 U.S. children aged 6...

In vivo sodium concentration continuously monitored with fluorescent sensors.

PubMed

Dubach, J Matthew; Lim, Edward; Zhang, Ning; Francis, Kevin P; Clark, Heather

2011-02-01

Sodium balance is vital to maintaining normal physiological function. Imbalances can occur in a variety of diseases, during certain surgical operations or during rigorous exercise. There is currently no method to continuously monitor sodium concentration in patients who may be susceptible to hyponatremia. Our approach was to design sodium specific fluorescent sensors capable of measuring physiological fluctuations in sodium concentration. The sensors are submicron plasticized polymer particles containing sodium recognition components that are coated with biocompatible poly(ethylene) glycol. Here, the sensors were brought up in saline and placed in the subcutaneous area of the skin of mice by simple injection. The fluorescence was monitored in real time using a whole animal imager to track changes in sodium concentrations. This technology could be used to monitor certain disease states or warn against dangerously low levels of sodium during exercise.

Dietary Sodium Restriction and Association with Urinary Marinobufagenin, Blood Pressure, and Aortic Stiffness

PubMed Central

Fedorova, Olga V.; Racine, Matthew L.; Geolfos, Candace J.; Gates, Phillip E.; Chonchol, Michel; Fleenor, Bradley S.; Lakatta, Edward G.; Bagrov, Alexei Y.; Seals, Douglas R.

2013-01-01

Summary Background and objectives Systolic BP and large elastic artery stiffness both increase with age and are reduced by dietary sodium restriction. Production of the natriuretic hormone marinobufagenin, an endogenous α1 Na+,K+-ATPase inhibitor, is increased in salt-sensitive hypertension and contributes to the rise in systolic BP during sodium loading. Design, setting, participants, & measurements The hypothesis was that dietary sodium restriction performed in middle-aged/older adults (eight men and three women; 60±2 years) with moderately elevated systolic BP (139±2/83±2 mmHg) would reduce urinary marinobufagenin excretion as well as systolic BP and aortic pulse-wave velocity (randomized, placebo-controlled, and crossover design). This study also explored the associations among marinobufagenin excretion with systolic BP and aortic pulse-wave velocity across conditions of 5 weeks of a low-sodium (77±9 mmol/d) and 5 weeks of a normal-sodium (144±7 mmol/d) diet. Results Urinary marinobufagenin excretion (weekly measurements; 25.4±1.8 versus 30.7±2.1 pmol/kg per day), systolic BP (127±3 versus 138±5 mmHg), and aortic pulse-wave velocity (700±40 versus 843±36 cm/s) were lower during the low- versus normal-sodium condition (all P<0.05). Across all weeks, marinobufagenin excretion was related with systolic BP (slope=0.61, P<0.001) and sodium excretion (slope=0.46, P<0.001). These associations persisted during the normal- but not the low-sodium condition (both P<0.005). Marinobufagenin excretion also was associated with aortic pulse-wave velocity (slope=0.70, P=0.02) and endothelial cell expression of NAD(P)H oxidase-p47phox (slope=0.64, P=0.006). Conclusions These results show, for the first time in humans, that dietary sodium restriction reduces urinary marinobufagenin excretion and that urinary marinobufagenin excretion is positively associated with systolic BP, aortic stiffness (aortic pulse-wave velocity), and endothelial cell expression of the oxidant enzyme NAD(P)H oxidase. Importantly, marinobufagenin excretion is positively related to systolic BP over ranges of sodium intake typical of an American diet, extending previous observations in rodents and humans fed experimentally high-sodium diets. PMID:23929930

µ-Conotoxins Modulating Sodium Currents in Pain Perception and Transmission: A Therapeutic Potential

PubMed Central

Tosti, Elisabetta; Boni, Raffaele

2017-01-01

The Conus genus includes around 500 species of marine mollusks with a peculiar production of venomous peptides known as conotoxins (CTX). Each species is able to produce up to 200 different biological active peptides. Common structure of CTX is the low number of amino acids stabilized by disulfide bridges and post-translational modifications that give rise to different isoforms. µ and µO-CTX are two isoforms that specifically target voltage-gated sodium channels. These, by inducing the entrance of sodium ions in the cell, modulate the neuronal excitability by depolarizing plasma membrane and propagating the action potential. Hyperexcitability and mutations of sodium channels are responsible for perception and transmission of inflammatory and neuropathic pain states. In this review, we describe the current knowledge of µ-CTX interacting with the different sodium channels subtypes, the mechanism of action and their potential therapeutic use as analgesic compounds in the clinical management of pain conditions. PMID:28937587

Benzonatate inhibition of voltage-gated sodium currents.

PubMed

Evans, M Steven; Maglinger, G Benton; Fletcher, Anita M; Johnson, Stephen R

2016-02-01

Benzonatate was FDA-approved in 1958 as an antitussive. Its mechanism of action is thought to be anesthesia of vagal sensory nerve fibers that mediate cough. Vagal sensory neurons highly express the Nav1.7 subtype of voltage-gated sodium channels, and inhibition of this channel inhibits the cough reflex. Local anesthetics inhibit voltage-gated sodium channels, but there are no reports of whether benzonatate affects these channels. Our hypothesis is that benzonatate inhibits Nav1.7 voltage-gated sodium channels. We used whole cell voltage clamp recording to test the effects of benzonatate on voltage-gated sodium (Na(+)) currents in two murine cell lines, catecholamine A differentiated (CAD) cells, which express primarily Nav1.7, and N1E-115, which express primarily Nav1.3. We found that, like local anesthetics, benzonatate strongly and reversibly inhibits voltage-gated Na(+) channels. Benzonatate causes both tonic and phasic inhibition. It has greater effects on channel inactivation than on activation, and its potency is much greater at depolarized potentials, indicating inactivated-state-specific effects. Na(+) currents in CAD cells and N1E-115 cells are similarly affected, indicating that benzonatate is not Na(+) channel subtype-specific. Benzonatate is a mixture of polyethoxy esters of 4-(butylamino) benzoic acid having varying degrees of hydrophobicity. We found that Na(+) currents are inhibited most potently by a benzonatate fraction containing the 9-ethoxy component. Detectable effects of benzonatate occur at concentrations as low as 0.3 μM, which has been reported in humans. We conclude that benzonatate has local anesthetic-like effects on voltage-gated sodium channels, including Nav1.7, which is a possible mechanism for cough suppression by the drug. Copyright © 2015 Elsevier Ltd. All rights reserved.

Alterations of sodium and potassium channels of RGCs in RCS rat with the development of retinal degeneration.

PubMed

Chen, Zhongshan; Song, Yanping; Yao, Junping; Weng, Chuanhuang; Yin, Zheng Qin

2013-11-01

All know that retinitis pigmentosa (RP) is a group of hereditary retinal degenerative diseases characterized by progressive dysfunction of photoreceptors and associated with progressive cells loss; nevertheless, little is known about how rods and cones loss affects the surviving inner retinal neurons and networks. Retinal ganglion cells (RGCs) process and convey visual information from retina to visual centers in the brain. The healthy various ion channels determine the normal reception and projection of visual signals from RGCs. Previous work on the Royal College of Surgeons (RCS) rat, as a kind of classical RP animal model, indicated that, at late stages of retinal degeneration in RCS rat, RGCs were also morphologically and functionally affected. Here, retrograde labeling for RGCs with Fluorogold was performed to investigate the distribution, density, and morphological changes of RGCs during retinal degeneration. Then, patch clamp recording, western blot, and immunofluorescence staining were performed to study the channels of sodium and potassium properties of RGCs, so as to explore the molecular and proteinic basis for understanding the alterations of RGCs membrane properties and firing functions. We found that the resting membrane potential, input resistance, and capacitance of RGCs changed significantly at the late stage of retinal degeneration. Action potential could not be evoked in a part of RGCs. Inward sodium current and outward potassium current recording showed that sodium current was impaired severely but only slightly in potassium current. Expressions of sodium channel protein were impaired dramatically at the late stage of retinal degeneration. The results suggested that the density of RGCs decreased, process ramification impaired, and sodium ion channel proteins destructed, which led to the impairment of electrophysiological functions of RGCs and eventually resulted in the loss of visual function.

Sodium MRI: Methods and applications

PubMed Central

Madelin, Guillaume; Lee, Jae-Seung; Regatte, Ravinder R.; Jerschow, Alexej

2014-01-01

Sodium NMR spectroscopy and MRI have become popular in recent years through the increased availability of high-field MRI scanners, advanced scanner hardware and improved methodology. Sodium MRI is being evaluated for stroke and tumor detection, for breast cancer studies, and for the assessment of osteoarthritis and muscle and kidney functions, to name just a few. In this article, we aim to present an up-to-date review of the theoretical background, the methodology, the challenges and limitations, and current and potential new applications of sodium MRI. PMID:24815363

The effects of amiloride and age on oxygen consumption coupled to electrogenic sodium transport in the human sigmoid colon.

PubMed

Carra, Graciela E; Matus, Daniel; Ibáñez, Jorge E; Saraví, Fernando D

2015-01-01

Aerobic metabolism is necessary for ion transport in many transporting epithelia, including the human colonic epithelium. We assessed the effects of the epithelial sodium channel blocker, amiloride, on oxygen consumption and short-circuit current of the human sigmoid epithelium to determine whether these effects were influenced by the age of the subject. Segments of the sigmoid colon were obtained from the safety margin of resections performed in patients of 62-77 years of age. Isolated mucosa preparations were obtained and mounted in airtight Ussing chambers, fit for simultaneous measurement of short-circuit current and oxygen concentration, before and after blocking epithelial sodium channels with amiloride (0.1 mmol/L). Regression analyses were performed to assess the associations between short-circuit current, oxygen consumption, and age of the subject as well as to define the relationship between the decreases in short-circuit current and oxygen consumption after blockade. Epithelial sodium channel blockade caused an 80% reduction in short-circuit current and a 26% reduction in oxygen consumption. Regression analysis indicated that both changes were significantly related (r = 0.884;P = 0.0007). Oxygen consumption decreased by 1 m mol/h/cm2 for each 25 m A/cm2 decrease in short-circuit current. Neither short-circuit current nor oxygen consumption had any significant relationship with the age of the subjects. The decrease in epithelial oxygen consumption caused by amiloride is proportional to the decrease in short-circuit current and independent of the age of the subject.

Comparative photodynamic therapy cytotoxicity of mannose-conjugated chlorin and talaporfin sodium in cultured human and rat cells.

PubMed

Shinoda, Yo; Takahashi, Tsutomu; Akimoto, Jiro; Ichikawa, Megumi; Yamazaki, Hiromi; Narumi, Atsushi; Yano, Shigenobu; Fujiwara, Yasuyuki

2017-01-01

Photodynamic therapy (PDT) is a Food and Drug Administration authorized method for cancer treatment, which uses photosensitizer and laser photo-irradiation to generate reactive oxygen species to induce cell death in tumors. Photosensitizers have been progressively developed, from first to third generation, with improvements in cell specificity, reduced side effects and toxicity, increased sensitivity for irradiation and reduced persistence of photosensitizer in healthy cells. These improvements have been achieved by basic comparative experiments between current and novel photosensitizers using cell lines; however, photosensitizers should be carefully evaluated because they may have cell type specificity. In the present study, we compared a third-generation photosensitizer, β-mannose-conjugated chlorin (β-M-chlorin), with the second generation, talaporfin sodium (NPe6), using seven different rat and human cell lines and a neuronal/glial primary culture prepared from rat embryos. NPe6 was more effective than β-M-chlorin in human-derived cell lines, and β-M-chlorin was more effective than NPe6 in rat primary cultures and rat-derived cell lines, except for the rat pheochromocytoma cell line, PC12. These differences of phototoxicity in different cell types are not because of differences in photosensitivity between the photosensitizers, but rather are associated with different distribution and accumulation rates in the different cell types. These data suggest that evaluation of photosensitizers for PDT should be carried out using as large a variety of cell types as possible because each photosensitizer may have cell type specificity.

Aconite poisoning.

PubMed

Chan, Thomas Y K

2009-04-01

Aconitine and related alkaloids found in the Aconitum species are highly toxic cardiotoxins and neurotoxins. The wild plant (especially the roots and root tubers) is extremely toxic. Severe aconite poisoning can occur after accidental ingestion of the wild plant or consumption of an herbal decoction made from aconite roots. In traditional Chinese medicine, aconite roots are used only after processing to reduce the toxic alkaloid content. Soaking and boiling during processing or decoction preparation will hydrolyze aconite alkaloids into less toxic and non-toxic derivatives. However, the use of a larger than recommended dose and inadequate processing increases the risk of poisoning. A Medline search (1963-February 2009) was conducted. Key articles with information on the use of aconite roots in traditional medicine, active (toxic) ingredients, mechanisms of toxicity, toxicokinetics of Aconitum alkaloids, and clinical features and management of aconite poisoning were reviewed. The cardiotoxicity and neurotoxicity of aconitine and related alkaloids are due to their actions on the voltage-sensitive sodium channels of the cell membranes of excitable tissues, including the myocardium, nerves, and muscles. Aconitine and mesaconitine bind with high affinity to the open state of the voltage-sensitive sodium channels at site 2, thereby causing a persistent activation of the sodium channels, which become refractory to excitation. The electrophysiological mechanism of arrhythmia induction is triggered activity due to delayed after-depolarization and early after-depolarization. The arrhythmogenic properties of aconitine are in part due to its cholinolytic (anticholinergic) effects mediated by the vagus nerve. Aconitine has a positive inotropic effect by prolonging sodium influx during the action potential. It has hypotensive and bradycardic actions due to activation of the ventromedial nucleus of the hypothalamus. Through its action on voltage-sensitive sodium channels in the axons, aconitine blocks neuromuscular transmission by decreasing the evoked quantal release of acetylcholine. Aconitine, mesaconitine, and hypaconitine can induce strong contractions of the ileum through acetylcholine release from the postganglionic cholinergic nerves. Patients present predominantly with a combination of neurological, cardiovascular, and gastrointestinal features. The neurological features can be sensory (paresthesia and numbness of face, perioral area, and the four limbs), motor (muscle weakness in the four limbs), or both. The cardiovascular features include hypotension, chest pain, palpitations, bradycardia, sinus tachycardia, ventricular ectopics, ventricular tachycardia, and ventricular fibrillation. The gastrointestinal features include nausea, vomiting, abdominal pain, and diarrhea. The main causes of death are refractory ventricular arrhythmias and asystole and the overall in-hospital mortality is 5.5%. Management of aconite poisoning is supportive, including immediate attention to the vital functions and close monitoring of blood pressure and cardiac rhythm. Inotropic therapy is required if hypotension persists and atropine should be used to treat bradycardia. Aconite-induced ventricular arrhythmias are often refractory to direct current cardioversion and antiarrhythmic drugs. Available clinical evidence suggests that amiodarone and flecainide are reasonable first-line treatment. In refractory cases of ventricular arrhythmias and cardiogenic shock, it is most important to maintain systemic blood flow, blood pressure, and tissue oxygenation by the early use of cardiopulmonary bypass. The role of charcoal hemoperfusion to remove circulating aconitine alkaloids is not established. Aconite roots contain aconitine, mesaconitine, hypaconitine, and other Aconitum alkaloids, which are known cardiotoxins and neurotoxins. Patients present predominantly with neurological, cardiovascular, and gastrointestinal features. Management is supportive; the early use of cardiopulmonary bypass is recommended if ventricular arrhythmias and cardiogenic shock are refractory to first-line treatment.

[Efficacy of sodium hydroxide at 2.5 %, chlorhexidine gluconate at 0.5 % and calcium hydroxide against Candida albicans].

PubMed

Ndiaye, D; Diongue, K; Bane, K; Seck, A; Niang, S O; Lèye Benoist, F; Ndiaye, D; Touré, B

2016-12-01

Endodontic flora is dominated in the apical part of the channels by strict anaerobic and some facultative anaerobic bacteria but also by Candida yeasts, especially Candida albicans species that are involved in the maintenance and persistence of endodontic infections. Their elimination of the canal system in practice by chemo-mechanical methods of disinfection is not always guaranteed. Thus, this in vitro study was performed to determine the sensitivity of C. albicans with sodium hypochlorite (NaOCl) dosed at 2.5 %, the chlorhexidine digluconate 0.5 % and calcium hydroxide used in inter-session medication. The diffusion method was used initially to test the sensitivity of C. albicans strains with the above products. Then a dilution technique has allowed us to determine the minimum inhibitory concentration of these active products on C. albicans. Strains from infected pulp teeth of patients showed a sensitivity of C. albicans to sodium hypochlorite to a minimum inhibitory concentration less than 70μg/mL and 30μg/mL for chlorhexidine. This study demonstrated a sensitivity of C. albicans to sodium hypochlorite and chlorhexidine. Copyright © 2016. Published by Elsevier Masson SAS.

Photometer for detection of sodium day airglow.

NASA Technical Reports Server (NTRS)

Mcmahon, D. J.; Manring, E. R.; Patty, R. R.

1973-01-01

Description of a photometer for daytime ground-based measurements of sodium airglow emission. The photometer described can be characterized by the following principal features: (1) a narrow (4.5-A) interference filter for initial discrimination; (2) cooled photomultiplier detector to reduce noise from dark current fluctuations and chopping to eliminate the average dark current; (3) a sodium vapor resonance cell to provide an effective bandpass comparable to the Doppler line width; (4) separate detection of all light transmitted by the interference filter to evaluate the Rayleigh and Mie components within the Doppler width of the resonance cell; and (5) temperature quenching of the resonance cell to evaluate and account for instrumental imperfections.

Phenomenological Studies on Sodium for CSP Applications: A Safety Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armijo, Kenneth Miguel; Andraka, Charles E.

Sodium as a heat transfer fluid (HTF) can achieve temperatures above 700°C to improve power cycle performance for reducing large infrastructure costs of high-temperature systems. Current concentrating solar power (CSP) sensible HTF’s (e.g. air, salts) have poor thermal conductivity, and thus low heat transfer capabilities, requiring a large receiver. The high thermal conductivity of sodium has demonstrated high heat transfer rates on dish and towers systems, which allow a reduction in receiver area by a factor of two to four, reducing re-radiation and convection losses and cost by a similar factor. Sodium produces saturated vapor at pressures suitable for transportmore » starting at 600°C and reaches one atmosphere at 870°C, providing a wide range of suitable latent operating conditions that match proposed high temperature, isothermal input power cycles. This advantage could increase the receiver and system efficiency while lowering the cost of CSP tower systems. Although there are a number of desirable thermal performance advantages associated with sodium, its propensity to rapidly oxidize presents safety challenges. This investigation presents a literature review that captures historical operations/handling lessons for advanced sodium systems, and the current state-of-knowledge related to sodium combustion behavior. Technical and operational solutions addressing sodium safety and applications in CSP will be discussed, including unique safety hazards and advantages using latent sodium. Operation and maintenance experience from the nuclear industry with sensible and latent systems will also be discussed in the context of safety challenges and risk mitigation solutions.« less

Sodium movements in perfused squid giant axons. Passive fluxes.

PubMed

Rojas, E; Canessa-Fischer, M

1968-08-01

Sodium movements in internally perfused giant axons from the squid Dosidicus gigas were studied with varying internal sodium concentrations and with fluoride as the internal anion. It was found that as the internal concentration of sodium was increased from 2 to 200 mM the resting sodium efflux increased from 0.09 to 34.0 pmoles/cm(2)sec and the average resting sodium influx increased from 42.9 to 64.5 pmoles/cm(2)sec but this last change was not statistically significant. When perfusing with a mixture of 500 mM K glutamate and 100 mM Na glutamate the resting efflux was 10 +/- 3 pmoles/cm(2)sec and 41 +/- 10 pmoles/cm(2)sec for sodium influx. Increasing the internal sodium concentration also increased both the extra influx and the extra efflux of sodium due to impulse propagation. At any given internal sodium concentration the net extra influx was about 5 pmoles/cm(2)impulse. This finding supports the notion that the inward current generated in a propagated action potential can be completely accounted for by movements of sodium.

Sodium Movements in Perfused Squid Giant Axons

PubMed Central

Rojas, Eduardo; Canessa-Fischer, Mitzy

1968-01-01

Sodium movements in internally perfused giant axons from the squid Dosidicus gigas were studied with varying internal sodium concentrations and with fluoride as the internal anion. It was found that as the internal concentration of sodium was increased from 2 to 200 mM the resting sodium efflux increased from 0.09 to 34.0 pmoles/cm2sec and the average resting sodium influx increased from 42.9 to 64.5 pmoles/cm2sec but this last change was not statistically significant. When perfusing with a mixture of 500 mM K glutamate and 100 mM Na glutamate the resting efflux was 10 ± 3 pmoles/cm2sec and 41 ± 10 pmoles/cm2sec for sodium influx. Increasing the internal sodium concentration also increased both the extra influx and the extra efflux of sodium due to impulse propagation. At any given internal sodium concentration the net extra influx was about 5 pmoles/cm2impulse. This finding supports the notion that the inward current generated in a propagated action potential can be completely accounted for by movements of sodium. PMID:5672003

Slowly inactivating component of Na+ current in peri-somatic region of hippocampal CA1 pyramidal neurons

PubMed Central

Park, Yul Young; Johnston, Daniel

2013-01-01

The properties of voltage-gated ion channels on the neuronal membrane shape electrical activity such as generation and backpropagation of action potentials, initiation of dendritic spikes, and integration of synaptic inputs. Subthreshold currents mediated by sodium channels are of interest because of their activation near rest, slow inactivation kinetics, and consequent effects on excitability. Modulation of these currents can also perturb physiological responses of a neuron that might underlie pathological states such as epilepsy. Using nucleated patches from the peri-somatic region of hippocampal CA1 neurons, we recorded a slowly inactivating component of the macroscopic Na+ current (which we have called INaS) that shared many biophysical properties with the persistent Na+ current, INaP, but showed distinctively faster inactivating kinetics. Ramp voltage commands with a velocity of 400 mV/s were found to elicit this component of Na+ current reliably. INaS also showed a more hyperpolarized I-V relationship and slower inactivation than those of the fast transient Na+ current (INaT) recorded in the same patches. The peak amplitude of INaS was proportional to the peak amplitude of INaT but was much smaller in amplitude. Hexanol, riluzole, and ranolazine, known Na+ channel blockers, were tested to compare their effects on both INaS and INaT. The peak conductance of INaS was preferentially blocked by hexanol and riluzole, but the shift of half-inactivation voltage (V1/2) was only observed in the presence of riluzole. Current-clamp measurements with hexanol suggested that INaS was involved in generation of an action potential and in upregulation of neuronal excitability. PMID:23236005

Supporting Academic Persistence in Low-Skilled Adult Learners

ERIC Educational Resources Information Center

O'Neill, Susan; Thomson, Margareta Maria

2013-01-01

The current literature review explores the factors that contribute to academic persistence for adult learners. The aim of the study is to identify current research-based strategies aimed at supporting learner persistence, particularly for low-skilled adults. Elements of three theoretical frameworks, namely, expectancy-value theory (EVT), goal…

Effects of nano red elemental selenium on sodium currents in rat dorsal root ganglion neurons.

PubMed

Yuan, Huijun; Lin, Jiarui; Lan, Tonghan

2006-01-01

Nano red elemental selenium (Nano-Se), was demonstrated to be useful in medical and scientific researches. Here, we investigated the effects of Nano-Se on sodium currents on rat dorsal root ganglion neurons (DRG), using the whole-cell patch clamp method. Nano-Se reversibly decrease the I(Na)(TTX-S) in a concentration-dependent, time-dependent and open-channel block manners without affecting I(Na)(TTX-R). It shifted the steady-state activation and inactivation curves for I(Na) to more negative potentials. In the research of recovery from inactivation, the recovery time constant is longer in the present of Nano-Se. Nano-Se had a weaker inhibitory effect on I(Na), compared with marked decrease caused by selenite which indicated that Nano-Se is less neurotoxic than selenite in short-term/large dose treatments and had similar bio availability to sodium selenite. The results of interaction between the effects of Nano-Se and selenite on sodium currents indicated a negative allosteric interaction between the selenite binding site and the Nano-Se binding site or that they have the same competitive binding site.

Effects of a behavioral intervention that emphasizes spices and herbs on adherence to recommended sodium intake: results of the SPICE randomized clinical trial12

PubMed Central

Anderson, Cheryl AM; Cobb, Laura K; Miller, Edgar R; Woodward, Mark; Hottenstein, Annette; Chang, Alex R; Mongraw-Chaffin, Morgana; White, Karen; Charleston, Jeanne; Tanaka, Toshiko; Thomas, Letitia; Appel, Lawrence J

2015-01-01

Background: For decades, dietary sodium intake in the United States has remained high, and few studies have examined strategies for maintaining recommended intakes. Objective: We examined the effects of a behavioral intervention, which emphasized spices and herbs, on the maintenance of sodium intake at the recommended intake of 1500 mg/d in individuals to whom the US Dietary Guidelines for Americans apply. Design: We conducted a 2-phase study that included adults ≥18 y of age for whom Dietary Guidelines for Americans recommends 1500 mg Na/d. The study was conducted in Baltimore, Maryland, from 2012 to 2014. In phase 1, 55 individuals consumed a low-sodium diet for 4 wk. Participants were provided all foods, snacks, and calorie-containing drinks. In phase 2, 40 participants from phase 1 were randomly assigned to either a behavioral intervention to reduce sodium intake (n = 20) or a self-directed control group (n = 20) for 20 wk. The primary study outcome was the change in mean 24-h urinary sodium excretion during phase 2. Linear regression analyses were used to determine intervention effects on urinary sodium excretion. Results: Participant characteristics were as follows: women: 65%; African American: 88%; hypertension: 63%; diabetes: 18%; mean age: 61 y; and mean body mass index (in kg/m2): 30. At the end of phase 2, mean 24-h sodium excretion was lower in the behavioral intervention than in the self-directed group (mean difference: −956.8 mg/d; 95% CI: −1538.7, −374.9 mg/d) after sodium intake at screening was controlled for (P = 0.002). These findings persisted in sensitivity analyses that excluded potentially incomplete urine collections [Mage’s equation mean difference: −1090 mg/d (P = 0.001); Joosens’ equation mean difference: −796 mg/d (P = 0.04)]. Conclusions: A multifactorial behavioral intervention emphasizing spices and herbs significantly reduced sodium intake. Because of the ubiquity of sodium in the US food supply, multilevel strategies addressing individual behaviors and the food supply are needed to improve adherence to recommendations. This trial was registered at clinicaltrials.gov as NCT01615159. PMID:26269371

Pyrethroids Differentially Alter Voltage-Gated Sodium Channels from the Honeybee Central Olfactory Neurons

PubMed Central

Kadala, Aklesso; Charreton, Mercedes; Jakob, Ingrid; Cens, Thierry; Rousset, Matthieu; Chahine, Mohamed; Le Conte, Yves; Charnet, Pierre; Collet, Claude

2014-01-01

The sensitivity of neurons from the honey bee olfactory system to pyrethroid insecticides was studied using the patch-clamp technique on central ‘antennal lobe neurons’ (ALNs) in cell culture. In these neurons, the voltage-dependent sodium currents are characterized by negative potential for activation, fast kinetics of activation and inactivation, and the presence of cumulative inactivation during train of depolarizations. Perfusion of pyrethroids on these ALN neurons submitted to repetitive stimulations induced (1) an acceleration of cumulative inactivation, and (2) a marked slowing of the tail current recorded upon repolarization. Cypermethrin and permethrin accelerated cumulative inactivation of the sodium current peak in a similar manner and tetramethrin was even more effective. The slow-down of channel deactivation was markedly dependent on the type of pyrethroid. With cypermethrin, a progressive increase of the tail current amplitude along with successive stimulations reveals a traditionally described use-dependent recruitment of modified sodium channels. However, an unexpected decrease in this tail current was revealed with tetramethrin. If one considers the calculated percentage of modified channels as an index of pyrethroids effects, ALNs are significantly more susceptible to tetramethrin than to permethrin or cypermethrin for a single depolarization, but this difference attenuates with repetitive activity. Further comparison with peripheral neurons from antennae suggest that these modifications are neuron type specific. Modeling the sodium channel as a multi-state channel with fast and slow inactivation allows to underline the effects of pyrethroids on a set of rate constants connecting open and inactivated conformations, and give some insights to their specificity. Altogether, our results revealed a differential sensitivity of central olfactory neurons to pyrethroids that emphasize the ability for these compounds to impair detection and processing of information at several levels of the bees olfactory pathway. PMID:25390654

Sodium hypochlorite (dilute chlorine bleach) oral rinse in patient self-care.

PubMed

Rich, Sandra K; Slots, Jørgen

2015-01-01

Sodium hypochlorite (NaOCl), commonly known as "bleach," is widely accepted as being a safe and effective antiseptic against bacteria, fungi, and viruses. For over a century, bleach has been used to control or overcome infection in homes, hospitals, and even on battlefields, and in endodontics for disinfection of root canals. This paper reviews clinical studies on the efficacy of sodium hypochlorite oral rinse to combat dental plaque and gingival inflammation. Sodium hypochlorite is readily available as inexpensive household bleach, and we suggest that oral rinsing twice weekly with dilute bleach (0.25% sodium hypochlorite) constitutes a valuable adjunct to current methods of plaque removal.

Effect of pH on the Transformation of a New Readymix Formulation of the Herbicides Bispyribac Sodium and Metamifop in Water.

PubMed

Saha, Suman; Majumder, Sambrita; Das, Sushovan; Das, Tapan Kumar; Bhattacharyya, Anjan; Roy, Sankhajit

2018-04-01

A laboratory experiment was conducted to investigate the effect of pH on the persistence and the dissipation of the new readymix formulation of bispyribac sodium and metamifop. The experiment was conducted in water of three different pH viz. 4.0, 7.0 and 9.2. The spiking level of both the compounds in water was 1.0 and 2.0 µg/mL. The residues were extracted by a simple, quick and reliable method and quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS). The method was justified based on the recovery study, which was > 85%. The dissipation of both compounds followed first order kinetics. The half-life values ranged between 19.86-36.29 and 9.92-19.69 days for bispyribac sodium and metamifop, respectively. The pH of water has a prominent effect on degradation of both the compounds. The rate of dissipation of both the compounds was highest in water of acidic pH followed by neutral and alkaline pH.

Soil analyses for 1,3-dichloropropene (1,3-DCP), sodium n-methyldithiocarbamate (metam-sodium), and their degradation products near Fort Hall Idaho, September 1999 through March 2000

USGS Publications Warehouse

Parliman, D.J.

2001-01-01

Between September 1999 and March 2000, soil samples from the Fort Hall, Idaho, area were analyzed for two soil fumigants, 1,3-dichloropropene (1,3-DCP) and sodium n-methyldithiocarbamate (metam-sodium), and their degradation products. Ground water is the only source of drinking water at Fort Hall, and the purpose of the investigation was to determine potential risk of ground-water contamination from persistence and movement of these pesticides in cropland soils. 1,3-DCP, metam-sodium, or their degradation products were detected in 42 of 104 soil samples. The samples were collected from 1-, 2-, and 3-foot depths in multiple backhoe trenches during four sampling events—before pesticide application in September; after application in October; before soil freeze in December; and after soil thaw in March. In most cases, concentrations of the pesticide compounds were at or near their laboratory minimum reporting limits. U.S. Environmental Protection Agency Method 5035 was used as the guideline for soil sample preparation and analyses, and either sodium bisulfate (NaHSO4), an acidic preservative, or pesticide-free water was added to samples prior to analyses. Addition of NaHSO4 to the samples resulted in a greater number of compound detections, but pesticide-free water was added to most samples to avoid the strong reactions of soil carbonate minerals with the NaHSO4. As a result, nondetection of compounds in samples containing pesticide-free water did not necessarily indicate that the compounds were absent. Detections of these compounds were inconsistent among trenches with similar soil characteristics and histories of soil fumigant use. Compounds were detected at different depths and different trench locations during each sampling event. Overall results of this study showed that the original compounds or their degradation products can persist in soil 6 months or more after their application and are present to at least 3 feet below land surface in some areas. A few of the soil analyses results were unexpected. Degradation products of metam-sodium were detected in samples from croplands with a history of 1,3-DCP applications only, and were not detected in samples from croplands with a history of metam-sodium applications. Although 1,2-dibromoethane (EDB) has not been used in the area for many years, EDB was detected in a few soil samples. The presence of EDB in soil could be caused by irrigation of croplands with EDBcontaminated ground water. Analyses of these soil samples resulted in many unanswered questions, and further studies are needed. One potential study to determine vertical extent of pesticide compound migration in sediments, for example, would include analysis of one or more columns of soil and sediments (land surface to ground water, about 35 to 50 feet below land surface) in areas with known soil contamination. Another study would expand the scope of soil contamination to include broader types of cropland conditions and compound analyses.

Use of Urine Biomarkers to Assess Sodium Intake: Challenges and Opportunities

PubMed Central

Maalouf, Joyce; Elliott, Paul; Loria, Catherine M.; Patel, Sheena; Bowman, Barbara A.

2017-01-01

This article summarizes current data and approaches to assess sodium intake in individuals and populations. A review of the literature on sodium excretion and intake estimation supports the continued use of 24-h urine collections for assessing population and individual sodium intake. Since 2000, 29 studies used urine biomarkers to estimate population sodium intake, primarily among adults. More than half used 24-h urine; the rest used a spot/casual, overnight, or 12-h specimen. Associations between individual sodium intake and health outcomes were investigated in 13 prospective cohort studies published since 2000. Only three included an indicator of long-term individual sodium intake, i.e., multiple 24-h urine specimens collected several days apart. Although not insurmountable, logistic challenges of 24-h urine collection remain a barrier for research on the relationship of sodium intake and chronic disease. Newer approaches, including modeling based on shorter collections, offer promise for estimating population sodium intake in some groups. PMID:25974702

Dietary sodium in chronic kidney disease: a comprehensive approach.

PubMed

Wright, Julie A; Cavanaugh, Kerri L

2010-01-01

Despite existing guidelines, dietary sodium intake among people worldwide often exceeds recommended limits. Research evidence is growing in both animal and human studies showing indirect and direct adverse consequences of high dietary sodium on the kidney. In patients with kidney disease, dietary sodium may have important effects on proteinuria, efficacy of antiproteinuric pharmacologic therapy, hypertension control, maintaining an optimal volume status, and immunosuppressant therapy. Dietary sodium intake is an important consideration in patients with all stages of chronic kidney disease, including those receiving dialysis therapy or those who have received a kidney transplant. We review in detail the dietary sodium recommendations suggested by various organizations for patients with kidney disease. Potential barriers to successfully translating current sodium intake guidelines into practice include poor knowledge about the sodium content of food among both patients and providers, complex labeling information, patient preferences related to taste, and limited support for modifications in public policy. Finally, we offer existing and potential solutions that may assist providers in educating and empowering patients to effectively manage their dietary sodium intake.

Ca2+ toxicity due to reverse Na+/Ca2+ exchange contributes to degeneration of neurites of DRG neurons induced by a neuropathy-associated Nav1.7 mutation

PubMed Central

Estacion, M.; Vohra, B. P. S; Liu, S.; Hoeijmakers, J.; Faber, C. G.; Merkies, I. S. J.; Lauria, G.; Black, J. A.

2015-01-01

Gain-of-function missense mutations in voltage-gated sodium channel Nav1.7 have been linked to small-fiber neuropathy, which is characterized by burning pain, dysautonomia and a loss of intraepidermal nerve fibers. However, the mechanistic cascades linking Nav1.7 mutations to axonal degeneration are incompletely understood. The G856D mutation in Nav1.7 produces robust changes in channel biophysical properties, including hyperpolarized activation, depolarized inactivation, and enhanced ramp and persistent currents, which contribute to the hyperexcitability exhibited by neurons containing Nav1.8. We report here that cell bodies and neurites of dorsal root ganglion (DRG) neurons transfected with G856D display increased levels of intracellular Na+ concentration ([Na+]) and intracellular [Ca2+] following stimulation with high [K+] compared with wild-type (WT) Nav1.7-expressing neurons. Blockade of reverse mode of the sodium/calcium exchanger (NCX) or of sodium channels attenuates [Ca2+] transients evoked by high [K+] in G856D-expressing DRG cell bodies and neurites. We also show that treatment of WT or G856D-expressing neurites with high [K+] or 2-deoxyglucose (2-DG) does not elicit degeneration of these neurites, but that high [K+] and 2-DG in combination evokes degeneration of G856D neurites but not WT neurites. Our results also demonstrate that 0 Ca2+ or blockade of reverse mode of NCX protects G856D-expressing neurites from degeneration when exposed to high [K+] and 2-DG. These results point to [Na+] overload in DRG neurons expressing mutant G856D Nav1.7, which triggers reverse mode of NCX and contributes to Ca2+ toxicity, and suggest subtype-specific blockade of Nav1.7 or inhibition of reverse NCX as strategies that might slow or prevent axon degeneration in small-fiber neuropathy. PMID:26156380

Contamination sources, serogroups, biofilm-forming ability and biocide resistance of Listeria monocytogenes persistent in tilapia-processing facilities.

PubMed

Vázquez-Sánchez, Daniel; Galvão, Juliana Antunes; Oetterer, Marília

2017-11-01

The major contamination sources, serogroups, biofilm-forming ability and biocide resistance of Listeria monocytogenes persistent in tilapia-processing facilities were assessed. Twenty-five processing-control points were examined twice in two factories, including whole tilapias, frozen fillets, water and food-contact surfaces. L. monocytogenes were detected in 4 and 20% of points of Factory A and B respectively, but at low concentrations. Contamination was due to inadequate handling of tilapias in the slaughter room of Factory A and to the application of ineffective sanitizing procedures in Factory B. Seven strains were characterized by RAPD-PCR using primers HLWL85, OPM-01 and DAF4. Genotypic similarity allowed tracing the contamination source of tilapia fillets in Factory B and detecting a prevalent strain in Brazilian tilapia-processing facilities. The serogroup II (including the serotype 1/2c) was the most frequently found, followed by serogroup I (1/2a) and III (1/2b), whereas the serotype 4b was not detected. All strains showed high biofilm-forming ability on stainless steel and polystyrene, but biofilm formation was positively correlated with the type of origin surface. Biofilms were highly resistant to peracetic acid and sodium hypochlorite, being required doses higher than those recommended by manufacturers to be eradicated. Peracetic acid was more effective than sodium hypochlorite, but the use of disinfectants with similar mechanisms of action increases the risk of cross-resistance. Case-by-case approaches are thus recommended to determine the sources and degree of contamination present in each factory, which would allow applying precise responses to control the persistence of bacterial pathogens such as L. monocytogenes .

A comparison of two different 2400 mOsm solutions for resuscitation of major burns.

PubMed

Milner, S M; Kinsky, M P; Guha, S C; Herndon, D N; Phillips, L G; Kramer, G C

1997-01-01

The reduction of burn edema is a common goal in the resuscitation of patients with thermal injury. Initial infusion of a 2400 mOsm hypertonic 7.5% NaCl 6% dextran (HSD) has been shown to reduce volume needs, but elevated serum sodium levels limit the dose that can be safely used. This study tested the hypothesis that a 2400 mOsm solution of NaCl, amino acids, glucose, and 6% dextran (Isosal-D) would reduce similar volume requirements while maintaining normal plasma sodium levels. Hemodynamics, plasma sodium, fluid balance, and tissue water content were measured after an initial baseline period and during resuscitation of a large scald injury in 21 anesthetized sheep. Resuscitation was begun 30 minutes after the scald with infusion of 10 ml/kg of either lactated Ringer's (LR), Isosal-D, or HSD and was continued with LR to restore and maintain baseline oxygen delivery throughout the 8-hour period. Oxygen delivery, cardiac output, and mean arterial pressure were rapidly reestablished by all three solutions, although a persistent tachycardia was noted with Isosal-D. Net fluid requirements of both HSD (35 +/- 13 ml/kg) and Isosal-D (72 +/- 13 ml/kg) were significantly lower than in the LR group (203 +/- 39 ml/kg). Mean serum sodium increased 11 mEq with HSD to a peak after 4 hours of 152 +/- 5 mEq, whereas with LR sodium fell 7 mEq to 132 +/- 4. Isosal-treated animals had minimal change in serum sodium. HSD significantly decreased tissue water content in colon, liver, pancreas, and nonburned skin compared with LR, whereas Isosal-D reduced edema only in the colon. It is concluded that in this protocol Isosal-D was not as effective as HSD at reducing volume needs and edema and had unexpected chronotropic effects.

Fatal complication of intravesical formalin during control of intractable hemorrhage from radiation cystitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, M.S.; Singhal, P.C.; Bapna, B.C.

Fatal acute tubular necrosis occurred in 1 patient in whom intravesical formalin was used to control massive persistent hemorrhage from radiation cystitis. A suggestion is made to monitor blood formic acid levels and institute prompt dialysis whenever these exceed 80 mg per 100 ml to avert such a catastrophe. Intravenous sodium bicarbonate appears to be indicated prophylactically in combating the associated metabolic acidosis due to absorbed formic acid.

Use of Vegetable Oil in Reductive Dechlorination of Tetrachloroethene

DTIC Science & Technology

2001-08-01

12.5 g sodium bicarbonate (Fisher Scientific Co.), and 4.412 g of citric acid , trisodium salt dihydrate (99%, Aldrich 62 Chemical Co. Inc.) to 1 L of...relatively quickly, leading to low donor efficiency. Biomass and acetate were the most significant products of vegoil- fed microcosms. Volatile fatty acids ...longer than 2 carbons rarely persisted. Since these acids can act as good secondary donors in the aqueous phase, their absence implies that the

Sodium titanate nanotubes as negative electrode materials for sodium-ion capacitors.

PubMed

Yin, Jiao; Qi, Li; Wang, Hongyu

2012-05-01

The lithium-based energy storage technology is currently being considered for electric automotive industry and even electric grid storage. However, the hungry demand for vast energy sources in the modern society will conflict with the shortage of lithium resources on the earth. The first alternative choice may be sodium-related materials. Herein, we propose an electric energy storage system (sodium-ion capacitor) based on porous carbon and sodium titanate nanotubes (Na-TNT, Na(+)-insertion compounds) as positive and negative electrode materials, respectively, in conjunction with Na(+)-containing non-aqueous electrolytes. As a low-voltage (0.1-2 V) sodium insertion nanomaterial, Na-TNT was synthesized via a simple hydrothermal reaction. Compared with bulk sodium titanate, the predominance of Na-TNT is the excellent rate performance, which exactly caters to the need for electrochemical capacitors. The sodium-ion capacitors exhibited desirable energy density and power density (34 Wh kg(-1), 889 W kg(-1)). Furthermore, the sodium-ion capacitors had long cycling life (1000 cycles) and high coulombic efficiency (≈ 98 % after the second cycle). More importantly, the conception of sodium-ion capacitor has been put forward.

Slack, Slick, and Sodium-Activated Potassium Channels

PubMed Central

Kaczmarek, Leonard K.

2013-01-01

The Slack and Slick genes encode potassium channels that are very widely expressed in the central nervous system. These channels are activated by elevations in intracellular sodium, such as those that occur during trains of one or more action potentials, or following activation of nonselective cationic neurotransmitter receptors such as AMPA receptors. This review covers the cellular and molecular properties of Slack and Slick channels and compares them with findings on the properties of sodium-activated potassium currents (termed KNa currents) in native neurons. Human mutations in Slack channels produce extremely severe defects in learning and development, suggesting that KNa channels play a central role in neuronal plasticity and intellectual function. PMID:24319675

SODIUM DITHIONITE INJECTIONS USED FOR CHROMIUM REDUCTION: NEWSLETTER

EPA Science Inventory

NEWSLETTER NRMRL-ADA- 02116 Paul*, C.J. "Sodium Dithionite Injections Used for Chromium Reduction." In: Groundwater Currents Newsletter 2002. A field-scale pilot study was conducted in 1999 at the U.S. Coast Guard Support Center in El...

Development of a Sodium Lidar for Space-Borne Missions

NASA Astrophysics Data System (ADS)

Janches, D.; Krainak, M. A.; Yu, A. W.; Jones, S.; Chen, J. R.

2015-12-01

We are currently developing laser and electro-optic technologies to remotely measure Sodium (Na) by adapting existing lidar technology with space flight heritage to study the composition and dynamics of Earth's mesosphere based on a spaceborne instrument that will measure the mesospheric Na layer. There is a pressing need in the Ionosphere - Thermosphere - Mesosphere (ITM) community for high-resolution measurements that can characterize the effect of small-scale dynamics (i.e. Gravity Waves with wavelengths smaller than a few hundred km) in the Mesosphere-Lower-Termosphere (MLT) on a global basis. This is compelling because they are believed to be the dominant contributors to momentum transport and deposition in the MLT, which largely drive the global circulation and thermal structure and interactions with the tides and planetary waves in this region. A nadir-pointing spaceborne Na Doppler resonance fluorescence LIDAR on board of the International Space Station (ISS) will essentially make high-resolution, in time and space, Na density, temperature and vertical wind measurements, from 75-115 km (MLT region). Our instrument concept consisted of a high-energy laser transmitter at 589 nm and highly sensitive photon counting detector that allows for range-resolved atmospheric-sodium-temperature profiles. The atmospheric temperature is deduced from the linewidth of the resonant fluorescence from the atomic sodium vapor D2 line as measured by our tunable laser. We are currently developing a high power energy laser that allows for some day time sodium lidar observations with the help of a narrow bandpass filter based on etalon or atomic sodium Faraday filter with ~5 to 10 pm optical bandwidth. The current baseline detector for the lidar instrument is a 16-channel Photomultiplier Tube with receiver electronics that has been space-qualified for the ICESat-2/ATLAS mission. Our technique uses the 16-channels as a photon-number-resolving "single" detector to provide the required full-spectroscopic sodium lineshape waveform for recovering Mesospheric temperature profiles. In this paper, we will describe our instrument concept for a future Heliophysics space mission based on board of the ISS as well as show current progress results.

Sodium transport modes in AMTEC electrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, R.M.; Homer, M.L.; Lara, L.

1998-07-01

Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Sodium transport has been characterized in a variety of AMTEC electrodes and several different transport modes clearly exist. Free molecular flow is the dominant transport mechanism in clean porous molybdenum and tungsten electrodes, and contributes to sodium transport in all porous electrodes, including WPt{sub 2}, WRh{sub 3}, and TiN. Molybdenum and tungsten electrodes containing phases such as Na{sub 2}MoO{sub 4} and Na{sub 2}WO{sub 4} exhibit very efficient sodium ion transport through themore » electrode in the ionic conducting phase. These electrodes also show reversible electrochemical reactions in which sodium ions and electrons are inserted or removed from into phases such as Na{sub 2}MoO{sub 4} and Na{sub 2}Mo{sub 3}O{sub 6} which are present in the electrode WPt{sub 2} and WRh{sub 3} electrodes typically exhibit both free molecular flow transport as well as an enhanced thermally activated transport mode which is probably surface and/or grain boundary diffusion of sodium in the alloy electrode. Data for large area WPt{sub 2} electrodes within a cylindrical heat shield are reported in this paper. Sodium transport away from these electrodes is effected by both the electrode's properties and the exterior environment which inhibits sodium gas flow to the condenser. Liquid alloy electrodes have been examined and have fairly efficient transport properties by liquid phase diffusion, but have generally not been considered advantageous for development. Titanium nitride, TiN, electrodes used in AMTEC cells, and similar electronically conducting refractory compounds such as TiB{sub 2} and NbN are always physically porous to some degree as formed by sputter deposition or screen printing, and these compounds sinter quite slowly. Hence free molecular flow is always a significant sodium transport mode in these electrodes. However, the sodium transport rate computed from the physical morphology of the electrodes is not as efficient as actual sodium transport in TiN electrodes, implicating an enhanced transport mode, which remains operational at lower AMTEC operating temperatures. Some TiN electrodes also have been found to exhibit electrochemical reactions involving electrode phases which persist in sodium exposure test cells at 1223K, as reported in this paper.« less

Preparation of Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) Material and its Application to Electrochemical Degradation of Methylene Blue in Sodium Chloride Solution

NASA Astrophysics Data System (ADS)

Riyanto; Prawidha, A. D.

2018-01-01

Electrochemical degradation of methylene blue using Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) electrode in sodium chloride have been done. The aim of this work was to degradation of methylene blue using Carbon-Chitosan-Polyvinyl Chloride (CC-PVC). Carbon chitosan composite electrode was preparing by Carbon and Chitosan powder and PVC in 4 mL tetrahydrofuran (THF) solvent and swirled flatly to homogeneous followed by drying in an oven at 100 °C for 3 h. The mixture was placed in stainless steel mould and pressed at 10 ton/cm2. Sodium chloride was used electrolyte solution. The effects of the current and electrolysis time were investigated using spectrophotometer UV-Visible. The experimental results showed that the carbon-chitosan composite electrode have higher effect in the electrochemical degradation of methylene blue in sodium chloride. Based on UV-visible spectra analysis shows current and electrolysis time has high effect to degradation of methylene blue in sodium chloride. Chitosan and polyvinyl chloride can strengthen the bond between the carbons so that the material has the high stability and conductivity. As conclusions is Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) electrode have a high electrochemical activity for degradation of methylene blue in sodium chloride.

Rapidly Synthesized, Few-Layered Pseudocapacitive SnS2 Anode for High-Power Sodium Ion Batteries.

PubMed

Thangavel, Ranjith; Samuthira Pandian, Amaresh; Ramasamy, Hari Vignesh; Lee, Yun-Sung

2017-11-22

The abundance of sodium resources has recently motivated the investigation of sodium ion batteries (SIBs) as an alternative to commercial lithium ion batteries. However, the low power and low capacity of conventional sodium anodes hinder their practical realization. Although most research has concentrated on the development of high-capacity sodium anodes, anodes with a combination of high power and high capacity have not been widely realized. Herein, we present a simple microwave irradiation technique for obtaining few-layered, ultrathin two-dimensional SnS 2 over graphene sheets in a few minutes. SnS 2 possesses a large number of active surface sites and exhibits high-capacity, rapid sodium ion storage kinetics induced by quick, nondestructive pseudocapacitance. Enhanced sodium ion storage at a high current density (12 A g -1 ), accompanied by high reversibility and high stability, was demonstrated. Additionally, a rationally designed sodium ion full cell coupled with SnS 2 //Na 3 V 2 (PO 4 ) 3 exhibited exceptional performance with high initial Coulombic efficiency (99%), high capacity, high stability, and a retention of ∼53% of the initial capacity even after the current density was increased by a factor of 140. In addition, a high specific energy of ∼140 Wh kg -1 and an ultrahigh specific power of ∼8.3 kW kg -1 (based on the mass of both the anode and cathode) were observed. Because of its outstanding performance and rapid synthesis, few-layered SnS 2 could be a promising candidate for practical realization of high-power SIBs.

Genistein inhibition of OGD-induced brain neuron death correlates with its modulation of apoptosis, voltage-gated potassium and sodium currents and glutamate signal pathway.

PubMed

Ma, Xue-Ling; Zhang, Feng; Wang, Yu-Xiang; He, Cong-Cong; Tian, Kun; Wang, Hong-Gang; An, Di; Heng, Bin; Liu, Yan-Qiang

2016-07-25

In the present study, we established an in vitro model of hypoxic-ischemia via exposing primary neurons of newborn rats to oxygen-glucose deprivation (OGD) and observing the effects of genistein, a soybean isoflavone, on hypoxic-ischemic neuron viability, apoptosis, voltage-activated potassium (Kv) and sodium (Nav) currents, and glutamate receptor subunits. The results indicated that OGD exposure reduced the viability and increased the apoptosis of brain neurons. Meanwhile, OGD exposure caused changes in the current-voltage curves and current amplitude values of voltage-activated potassium and sodium currents; OGD exposure also decreased GluR2 expression and increased NR2 expression. However, genistein at least partially reversed the effects caused by OGD. The results suggest that hypoxic-ischemia-caused neuronal apoptosis/death is related to an increase in K(+) efflux, a decrease in Na(+) influx, a down-regulation of GluR2, and an up-regulation of NR2. Genistein may exert some neuroprotective effects via the modulation of Kv and Nav currents and the glutamate signal pathway, mediated by GluR2 and NR2. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Observation of long-lived persistent spin polarization in a topological insulator

NASA Astrophysics Data System (ADS)

Tian, Jifa; Hong, Seokmin; Miotkowski, Ireneusz; Datta, Supriyo; Chen, Yong P.

3D Topological insulators (TI), featuring helically spin-momentum-locked topological surface states (TSS), are considered promising for spintronics applications. Several recent experiments in TIs have demonstrated a current induced electronic spin polarization that may be used for all electrical spin generation and injection. Here, we report spin potentiometric measurements in TIs that have revealed a long-lived persistent electron spin polarization even at zero current. Unaffected by a small bias current and persisting for several days at low temperature, the spin polarization can be induced and reversed by a large ``writing'' current applied for an extended time. Such an electrically controlled persistent spin polarization with unprecedented long lifetime could enable a rechargeable spin battery and rewritable spin memory for potential applications in spintronics and quantum information.

Cardiac sodium channel Markov model with temperature dependence and recovery from inactivation.

PubMed Central

Irvine, L A; Jafri, M S; Winslow, R L

1999-01-01

A Markov model of the cardiac sodium channel is presented. The model is similar to the CA1 hippocampal neuron sodium channel model developed by Kuo and Bean (1994. Neuron. 12:819-829) with the following modifications: 1) an additional open state is added; 2) open-inactivated transitions are made voltage-dependent; and 3) channel rate constants are exponential functions of enthalpy, entropy, and voltage and have explicit temperature dependence. Model parameters are determined using a simulated annealing algorithm to minimize the error between model responses and various experimental data sets. The model reproduces a wide range of experimental data including ionic currents, gating currents, tail currents, steady-state inactivation, recovery from inactivation, and open time distributions over a temperature range of 10 degrees C to 25 degrees C. The model also predicts measures of single channel activity such as first latency, probability of a null sweep, and probability of reopening. PMID:10096885

Effect of Changes in Transepithelial Transport on the Uptake of Sodium across the Outer Surface of the Frog Skin

PubMed Central

Biber, Thomas U. L.

1971-01-01

The unidirectional sodium, uptake at the outer surface of the frog skin was measured by the method described by Biber and Curran (8). With bathing solutions containing 6 mM NaCl there is a good correlation between sodium uptake and short-circuit current (SCC) measured simultaneously except that the average uptake is about 40% higher than the average SCC. The discrepancy between uptake and SCC increases approximately in proportion to an increase in sodium concentration of the bathing solutions. Amiloride inhibits the unidirectional sodium uptake by 21 and 69% at a sodium concentration of 115 and 6 mM, respectively. This indicates that amiloride acts on the entry step of sodium but additional effects cannot be excluded. The sodium, uptake is not affected by 10-4 M ouabain at a sodium concentration of 115 mM but is inhibited by 40% at a sodium concentration of 6 mM. Replacement of air by nitrogen leads to a 40% decrease of sodium uptake at a sodium concentration of 6 mM. The results support the view proposed previously (8) that the sodium uptake is made up of two components, a linear component which is, essentially, not involved in transepithelial movement of sodium and a saturating component which reflects changes in transepithelial transport. Amiloride, seems largely to affect the saturating component. PMID:5559619

Identification of an ovarian voltage-activated Na+-channel type: hints to involvement in luteolysis.

PubMed

Bulling, A; Berg, F D; Berg, U; Duffy, D M; Stouffer, R L; Ojeda, S R; Gratzl, M; Mayerhofer, A

2000-07-01

An endocrine type of voltage-activated sodium channel (eNaCh) was identified in the human ovary and human luteinized granulosa cells (GC). Whole-cell patch-clamp studies showed that the eNaCh in GC is functional and tetrodotoxin (TTX) sensitive. The luteotrophic hormone human CG (hCG) was found to decrease the peak amplitude of the sodium current within seconds. Treatment with hCG for 24-48 h suppressed not only eNaCh mRNA levels, but also mean Na+ peak currents and resting membrane potentials. An unexpected role for eNaChs in regulating cell morphology and function was indicated after pharmacological modulation of presumed eNaCh steady-state activity in GC cultures for 24-48 h using TTX (NaCh blocker) and veratridine (NaCh activator). TTX preserved a highly differentiated cellular phenotype. Veratridine not only increased the number of secondary lysosomes but also led to a significantly reduced progesterone production. Importantly, endocrine cells of the nonhuman primate corpus luteum (CL), which represent in vivo counterparts of luteinized GC, also contain eNaCh mRNA. Although the mechanism of channel activity under physiological conditions is not clear, it may include persistent Na+ currents. As observed in GC in culture, abundant secondary lysosomes were particularly evident in the regressing CL, suggesting a functional link between eNaCh activity and this form of cellular regression in vivo. Our results identify eNaCh in ovarian endocrine cells and demonstrate that their expression is under the inhibitory control of hCG. Activation of eNaChs in luteal cells, due to loss of gonadotropin support, may initiate a cascade of events leading to decreased CL function, a process that involves lysosomal activation and autophagy. These results imply that ovarian eNaChs are involved in the physiological demise of the temporary endocrine organ CL in the primate ovary during the menstrual cycle. Because commonly used drugs, including phenytoin, target NaChs, these results may be of clinical relevance.

Electrophysiology of sodium-coupled transport in proximal renal tubules.

PubMed

Lang, F; Messner, G; Rehwald, W

1986-06-01

Effects of sodium-coupled transport on intracellular electrolytes and electrical properties of proximal renal tubule cells are described in this review. Simultaneous with addition of substrate for sodium-coupled transport to luminal perfusates, both cell membranes depolarize. The luminal cell membrane depolarizes due to opening of sodium-cotransport pathways. The depolarization of the peritubular cell membrane during sodium-coupled transport is primarily due to a circular current reentering the lumen via the paracellular pathway. The depolarization leads to a transient decrease of basolateral potassium conductance that in turn amplifies the depolarization. However, within 5-10 min of continued exposure to substrate, potassium conductance increases again, and peritubular cell membrane repolarizes. During depolarization the driving force of peritubular bicarbonate exit is reduced. As a result net alkalinization of the cell prevails despite an increase of intracellular sodium activity, which reduces the driving force for the sodium-hydrogen ion exchanger and would thus have been expected to acidify the cell. No evidence is obtained for regulatory inhibition of sodium-coupled transport by intracellular sodium or calcium. Rather, luminal cotransport is altered by the change of driving forces.

Dietary Sodium in Chronic Kidney Disease: A Comprehensive Approach

PubMed Central

Wright, Julie A.; Cavanaugh, Kerri L.

2010-01-01

Despite existing guidelines, dietary sodium intake among people worldwide often exceeds recommended limits. Research evidence is growing in both animal and human studies showing indirect and direct adverse consequences of high dietary sodium on the kidney. In patients with kidney disease, dietary sodium may have important effects on proteinuria, efficacy of antiproteinuric pharmacologic therapy, hypertension control, maintaining an optimal volume status, and immunosuppressant therapy. Dietary sodium intake is an important consideration in patients with all stages of chronic kidney disease, including those receiving dialysis therapy or those who have received a kidney transplant. We review in detail the dietary sodium recommendations suggested by various organizations for patients with kidney disease. Potential barriers to successfully translating current sodium intake guidelines into practice include poor knowledge about the sodium content of food among both patients and providers, complex labeling information, patient preferences related to taste, and limited support for modifications in public policy. Finally, we offer existing and potential solutions that may assist providers in educating and empowering patients to effectively manage their dietary sodium intake. PMID:20557489

Sodium and potassium conductance changes during a membrane action potential

PubMed Central

Bezanilla, Francisco; Rojas, Eduardo; Taylor, Robert E.

1970-01-01

1. A method for turning a membrane potential control system on and off in less than 10 μsec is described. This method was used to record membrane currents in perfused giant axons from Dosidicus gigas and Loligo forbesi after turning on the voltage clamp system at various times during the course of a membrane action potential. 2. The membrane current measured just after the capacity charging transient was found to have an almost linear relation to the controlled membrane potential. 3. The total membrane conductance taken from these current—voltage curves was found to have a time course during the action potential similar to that found by Cole & Curtis (1939). 4. The instantaneous current voltage curves were linear enough to make it possible to obtain a good estimate of the individual sodium and potassium channel conductances, either algebraically or by clamping to the sodium, or potassium, reversal potentials. Good general agreement was obtained with the predictions of the Hodgkin—Huxley equations. 5. We consider these results to constitute the first direct experimental demonstration of the conductance changes to sodium and potassium during the course of an action potential. PMID:5505231

Direct demonstration of persistent Na+ channel activity in dendritic processes of mammalian cortical neurones

PubMed Central

Magistretti, Jacopo; Ragsdale, David S; Alonso, Angel

1999-01-01

Single Na+ channel activity was recorded in patch-clamp, cell-attached experiments performed on dendritic processes of acutely isolated principal neurones from rat entorhinal-cortex layer II. The distances of the recording sites from the soma ranged from ≈20 to ≈100 μm.Step depolarisations from holding potentials of −120 to −100 mV to test potentials of −60 to +10 mV elicited Na+ channel openings in all of the recorded patches (n= 16).In 10 patches, besides transient Na+ channel openings clustered within the first few milliseconds of the depolarising pulses, prolonged and/or late Na+ channel openings were also regularly observed. This ‘persistent’ Na+ channel activity produced net inward, persistent currents in ensemble-average traces, and remained stable over the entire duration of the experiments (≈9 to 30 min).Two of these patches contained <= 3 channels. In these cases, persistent Na+ channel openings could be attributed to the activity of one single channel.The voltage dependence of persistent-current amplitude in ensemble-average traces closely resembled that of whole-cell, persistent Na+ current expressed by the same neurones, and displayed the same characteristic low threshold of activation.Dendritic, persistent Na+ channel openings had relatively high single-channel conductance (≈20 pS), similar to what is observed for somatic, persistent Na+ channels.We conclude that a stable, persistent Na+ channel activity is expressed by proximal dendrites of entorhinal-cortex layer II principal neurones, and can contribute a significant low-threshold, persistent Na+ current to the dendritic processing of excitatory synaptic inputs. PMID:10601494

The effects of hurricane Rita and subsequent drought on alligators in southwest Louisiana.

PubMed

Lance, Valentine A; Elsey, Ruth M; Butterstein, George; Trosclair, Phillip L; Merchant, Mark

2010-02-01

Hurricane Rita struck the coast of southwest Louisiana in September 2005. The storm generated an enormous tidal surge of approximately four meters in height that inundated many thousands of acres of the coastal marsh with full strength seawater. The initial surge resulted in the deaths of a number of alligators and severely stressed those who survived. In addition, a prolonged drought (the lowest rainfall in 111 years of recorded weather data) following the hurricane resulted in highly saline conditions that persisted in the marsh for several months. We had the opportunity to collect 11 blood samples from alligators located on Holly Beach less than a month after the hurricane, but were unable to collect samples from alligators on Rockefeller Wildlife Refuge until February 2006. Conditions at Rockefeller Refuge did not permit systematic sampling, but a total of 201 samples were collected on the refuge up through August 2006. The blood samples were analyzed for sodium, potassium, chloride, osmolality, and corticosterone. Blood samples from alligators sampled on Holly Beach in October 2005, showed a marked elevation in plasma osmolality, sodium, chloride, potassium, corticosterone, and an elevated heterophil/lymphocyte ratio. Blood samples from alligators on Rockefeller Refuge showed increasing levels of corticosterone as the drought persisted and elevated osmolality and electrolytes. After substantial rainfall in July and August, these indices of osmotic stress returned to within normal limits. (c) 2009 Wiley-Liss, Inc.

Environmentally persistent free radicals (EPFRs)-2. Are free hydroxyl radicals generated in aqueous solutions?

PubMed

Khachatryan, Lavrent; Dellinger, Barry

2011-11-01

A chemical spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), in conjunction with electron paramagnetic resonance (EPR) spectroscopy was employed to measure the production of hydroxyl radical (·OH) in aqueous suspensions of 5% Cu(II)O/silica (3.9% Cu) particles containing environmentally persistent free radicals (EPFRs) of 2-monochlorophenol (2-MCP). The results indicate: (1) a significant differences in accumulated DMPO-OH adducts between EPFR containing particles and non-EPFR control samples, (2) a strong correlation between the concentration of DMPO-OH adducts and EPFRs per gram of particles, and (3) a slow, constant growth of DMPO-OH concentration over a period of days in solution containing 50 μg/mL EPFRs particles + DMPO (150 mM) + reagent balanced by 200 μL phosphate buffered (pH = 7.4) saline. However, failure to form secondary radicals using standard scavengers, such as ethanol, dimethylsulfoxide, sodium formate, and sodium azide, suggests free hydroxyl radicals may not have been generated in solution. This suggests surface-bound, rather than free, hydroxyl radicals were generated by a surface catalyzed-redox cycle involving both the EPFRs and Cu(II)O. Toxicological studies clearly indicate these bound free radicals promote various types of cardiovascular and pulmonary disease normally attributed to unbound free radicals; however, the exact chemical mechanism deserves further study in light of the implication of formation of bound, rather than free, hydroxyl radicals.

The Daily Consumption of Cola Can Determine Hypocalcemia: A Case Report of Postsurgical Hypoparathyroidism-Related Hypocalcemia Refractory to Supplemental Therapy with High Doses of Oral Calcium.

PubMed

Guarnotta, Valentina; Riela, Serena; Massaro, Marina; Bonventre, Sebastiano; Inviati, Angela; Ciresi, Alessandro; Pizzolanti, Giuseppe; Benvenga, Salvatore; Giordano, Carla

2017-01-01

The consumption of soft drinks is a crucial factor in determining persistent hypocalcemia. The aim of the study is to evaluate the biochemical mechanisms inducing hypocalcemia in a female patient with usual high consumption of cola drink and persistent hypocalcemia, who failed to respond to high doses of calcium and calcitriol supplementation. At baseline and after pentagastrin injection, gastric secretion (Gs) and duodenal secretion (Ds) samples were collected and calcium and total phosphorus (P tot ) concentrations were evaluated. At the same time, blood calcium, P tot , sodium, potassium, chloride, magnesium concentrations, and vitamin D were sampled. After intake of cola (1 L) over 180 min, Gs and Ds and blood were collected and characterized in order to analyze the amount of calcium and P tot or sodium, potassium, magnesium, and chloride ions, respectively. A strong pH decrease was observed after cola intake with an increase in phosphorus concentration. Consequently, a decrease in calcium concentration in Gs and Ds was observed. A decrease in calcium concentration was also observed in blood. In conclusion, we confirm that in patients with postsurgical hypoparathyroidism, the intake of large amounts of cola containing high amounts of phosphoric acid reduces calcium absorption efficiency despite the high doses of calcium therapy.

Effect of diquafosol tetrasodium eye drop for persistent dry eye after laser in situ keratomileusis.

PubMed

Mori, Yosai; Nejima, Ryohei; Masuda, Ayami; Maruyama, Yoko; Minami, Keiichiro; Miyata, Kazunori; Amano, Shiro

2014-07-01

To evaluate the effect of diquafosol tetrasodium (DQS) for the treatment of persistent dry eye after laser in situ keratomileusis (LASIK). Miyata Eye Hospital, Miyazaki, Japan. Noncomparative case series. This prospective study included 30 eyes of 15 patients in whom dry eye had persisted for over 12 months after LASIK, and the symptoms had not improved with artificial tears and sodium hyaluronate treatment. In addition, treatment with DQS 3% eye drops, 6 times a day, was performed for 12 weeks. Best-corrected visual acuity, tear secretion with the Schirmer test, tear break-up time, and fluorescein and lissamine green staining scores on the cornea and conjunctiva were examined before and at 1, 4, and 12 weeks after the addition. A subjective questionnaire of 14 symptoms was also assessed before and 12 weeks after treatment. The fluorescein and lissamine green staining scores significantly improved over 12 weeks; however, the best-corrected visual acuity and tear secretion did not change. The symptoms of fatigue, dryness, grittiness, discomfort, difficulty in reading, and discomfort within the area of dryness improved after the additional DQS treatment. The DQS treatment improved the subjective and objective symptoms of persistent dry eye after LASIK. Increased mucin production because of the addition of DQS probably improved the tear film stability and reduced the symptoms of dry eye in patients who had persistent dry eye after LASIK.

Strategies to reduce sodium consumption: a food industry perspective.

PubMed

Dötsch, Mariska; Busch, Johanneke; Batenburg, Max; Liem, Gie; Tareilus, Erwin; Mueller, Rudi; Meijer, Gert

2009-11-01

The global high prevalence of hypertension and cardiovascular disease has raised concerns regarding the sodium content of the foods which we consume. Over 75% of sodium intake in industrialized diets is likely to come from processed and restaurant foods. Therefore international authorities, such as the World Health Organisation, are encouraging the food industry to reduce sodium levels in their products. Significant sodium reduction is not without complications as salt plays an important role in taste, and in some products is needed also for preservation and processing. The most promising sodium reduction strategy is to adapt the preference of consumers for saltiness by reducing sodium in products in small steps. However, this is a time-consuming approach that needs to be applied industry-wide in order to be effective. Therefore the food industry is also investigating solutions that will maintain the same perceived salt intensity at lower sodium levels. Each of these has specific advantages, disadvantages, and time lines for implementation. Currently applied approaches are resulting in sodium reduction between 20-30%. Further reduction will require new technologies. Research into the physiology of taste perception and salt receptors is an emerging area of science that is needed in order to achieve larger sodium reductions.

Blood pressure reduction by reducing sodium intake in the population: one shoe fits all?

PubMed

Teo, Koon; Mente, Andrew

2014-07-01

Current guidelines, based on extrapolations of observational studies or short-term relatively small clinical trials, recommend that daily sodium intake should be around 2 g/day or less. The assumption is that the relationship between sodium consumption and blood pressure (BP) levels is linear in all populations. Recent development suggests this may not be correct. We reviewed the literature on the association between sodium reduction and BP lowering, and preliminary data on 100,000 individuals from the Prospective Urban Rural Epidemiology study on sodium excretion and the association of sodium excretion with BP in general populations from 17 countries in five continents, with a focus on major subgroups. Earlier observational studies have shown inconsistencies in their findings which were not addressed by the recommendations. The PURE results showed that associations between sodium intake and BP were not linear; proportionally, higher BP was found in individuals with higher sodium intake compared with those with lower sodium intake, in individuals with hypertension compared to those without hypertension, and in older individuals compared with younger individuals. Recent data do not support the recommendation that all populations should reduce their sodium intake to one low level.

Cardiac safety of lacosamide: the non-clinical perspective.

PubMed

Delaunois, A; Colomar, A; Depelchin, B O; Cornet, M

2015-11-01

Lacosamide is indicated for the adjunctive treatment of partial-onset seizures in adult patients. Unlike other sodium channel-blocking antiepileptic drugs, lacosamide selectively enhances sodium channel slow inactivation. Potential effects of lacosamide on cardiac sodium channels and their cardiovascular consequences were comprehensively assessed. This manuscript presents the non-clinical cardiac safety profile of lacosamide. Lacosamide was tested in vitro on sodium and L-type calcium currents from isolated human atrial myocytes and on hERG-mediated potassium currents from stably transfected HEK293 cells. Cardiac action potentials were recorded in guinea pig ventricular myocytes. In vivo, hemodynamic and ECG parameters were evaluated in anesthetized dogs and monkeys receiving acute cumulative intravenous doses of lacosamide. Following intravenous dosing with lacosamide, dose-dependent PR and QRS prolongation and ECG abnormalities (loss of P waves, atrioventricular and intraventricular blocks, junctional premature contractions) were observed in anesthetized dogs and monkeys. In vitro, lacosamide reduced human cardiac sodium currents in a concentration-, voltage- and state-dependent manner. Lacosamide reductions in Vmax in guinea pig myocytes were similar to lamotrigine and carbamazepine. Lacosamide showed no relevant inhibitory effects on hERG and L-type calcium channels and did not prolong QTc in vivo. ECG findings in anesthetized animals correlate well with in vitro sodium channel-related effects and are also consistent with those (PR prolongation, first-degree atrioventricular block) reported in healthy volunteers and patients with epilepsy. Both in vivo and in vitro effects were detected from exposure levels 1.5- to 2-fold above those achieved with the maximum-recommended human lacosamide dose (400 mg/day). © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Alanine to valine substitutions in the pore helix IIIP1 and linker-helix IIIL45 confer cockroach sodium channel resistance to DDT and pyrethroids.

PubMed

Chen, Mengli; Du, Yuzhe; Nomura, Yoshiko; Zhu, Guonian; Zhorov, Boris S; Dong, Ke

2017-05-01

Pyrethroid insecticides exert toxic effects by prolonging the opening of voltage-gated sodium channels. More than 20 sodium channel mutations from arthropod pests and disease vectors have been confirmed to confer pyrethroid resistance. These mutations have been valuable in elucidating the molecular interaction between pyrethroids and sodium channels, including identification of two pyrethroid receptor sites. Previously, two alanine to valine substitutions, one in the pore helix IIIP1 and the other in the linker-helix connecting S4 and S5 in domain III (IIIL45), were found in Drosophila melanogaster mutants that are resistant to DDT and deltamethrin (a type II pyrethroid with an α-cyano group at the phenylbenzyl alcohol position, which is lacking in type I pyrethroids), but their role in target-site-mediated insecticide resistance has not been functionally confirmed. In this study, we functionally examined the two mutations in cockroach sodium channels expressed in Xenopus laevis oocytes. Both mutations caused depolarizing shifts in the voltage dependence of activation, conferred DDT resistance and also resistance to two Type I pyrethroids by almost abolishing the tail currents induced by Type I pyrethroids. In contrast, neither mutation reduced the amplitude of tail currents induced by the Type II pyrethroids, deltamethrin or cypermethrin. However, both mutations accelerated the decay of Type II pyrethroid-induced tail currents, which normally decay extremely slowly. These results provided new insight into the molecular basis of different actions of Type I and Type II pyrethroids on sodium channels. Computer modeling predicts that both mutations may allosterically affect pyrethroid binding. Copyright © 2016 Elsevier B.V. All rights reserved.

Zn2+ reduction induces neuronal death with changes in voltage-gated potassium and sodium channel currents.

PubMed

Tian, Kun; He, Cong-Cong; Xu, Hui-Nan; Wang, Yu-Xiang; Wang, Hong-Gang; An, Di; Heng, Bin; Pang, Wei; Jiang, Yu-Gang; Liu, Yan-Qiang

2017-05-01

In the present study, cultured rat primary neurons were exposed to a medium containing N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a specific cell membrane-permeant Zn 2+ chelator, to establish a model of free Zn 2+ deficiency in neurons. The effects of TPEN-mediated free Zn 2+ ion reduction on neuronal viability and on the performance of voltage-gated sodium channels (VGSCs) and potassium channels (Kvs) were assessed. Free Zn 2+ deficiency 1) markedly reduced the neuronal survival rate, 2) reduced the peak amplitude of I Na , 3) shifted the I Na activation curve towards depolarization, 4) modulated the sensitivity of sodium channel voltage-dependent inactivation to a depolarization voltage, and 5) increased the time course of recovery from sodium channel inactivation. In addition, free Zn 2+ deficiency by TPEN notably enhanced the peak amplitude of transient outward K + currents (I A ) and delayed rectifier K + currents (I K ), as well as caused hyperpolarization and depolarization directional shifts in their steady-state activation curves, respectively. Zn 2+ supplementation reversed the effects induced by TPEN. Our results indicate that free Zn 2+ deficiency causes neuronal damage and alters the dynamic characteristics of VGSC and Kv currents. Thus, neuronal injury caused by free Zn 2+ deficiency may correlate with its modulation of the electrophysiological properties of VGSCs and Kvs. Copyright © 2017 Elsevier GmbH. All rights reserved.

Global Nav1.7 Knockout Mice Recapitulate the Phenotype of Human Congenital Indifference to Pain

PubMed Central

Gingras, Jacinthe; Smith, Sarah; Matson, David J.; Johnson, Danielle; Nye, Kim; Couture, Lauren; Feric, Elma; Yin, Ruoyuan; Moyer, Bryan D.; Peterson, Matthew L.; Rottman, James B.; Beiler, Rudolph J.; Malmberg, Annika B.; McDonough, Stefan I.

2014-01-01

Clinical genetic studies have shown that loss of Nav1.7 function leads to the complete loss of acute pain perception. The global deletion is reported lethal in mice, however, and studies of mice with promoter-specific deletions of Nav1.7 have suggested that the role of Nav1.7 in pain transduction depends on the precise form of pain. We developed genetic and animal husbandry strategies that overcame the neonatal-lethal phenotype and enabled construction of a global Nav1.7 knockout mouse. Knockouts were anatomically normal, reached adulthood, and had phenotype wholly analogous to human congenital indifference to pain (CIP): compared to littermates, knockouts showed no defects in mechanical sensitivity or overall movement yet were completely insensitive to painful tactile, thermal, and chemical stimuli and were anosmic. Knockouts also showed no painful behaviors resulting from peripheral injection of nonselective sodium channel activators, did not develop complete Freund’s adjuvant-induced thermal hyperalgesia, and were insensitive to intra-dermal histamine injection. Tetrodotoxin-sensitive sodium current recorded from cell bodies of isolated sensory neurons and the mechanically-evoked spiking of C-fibers in a skin-nerve preparation each were reduced but not eliminated in tissue from knockouts compared to littermates. Results support a role for Nav1.7 that is conserved between rodents and humans and suggest several possibly translatable biomarkers for the study of Nav1.7-targeted therapeutics. Results further suggest that Nav1.7 may retain its key role in persistent as well as acute forms of pain. PMID:25188265

Spontaneous and persistent currents in superconductive and mesoscopic structures (Review)

NASA Astrophysics Data System (ADS)

Kulik, I. O.

2004-07-01

We briefly review aspects of superconductive persistent currents in Josephson junctions of the S/I/S, S/O/S and S/N/S types, focusing on the origin of jumps in the current versus phase dependences, and discuss in more detail the persistent and the "spontaneous" currents in Aharonov-Bohm mesoscopic and nanoscopic (macromolecular) structures. A fixed-number-of-electrons mesoscopic or macromolecular conducting ring is shown to be unstable against structural transformation removing spatial symmetry (in particular, azimuthal periodicity) of its electron-lattice Hamiltonian. In the case when the transformation is blocked by strong coupling to an external azimuthally symmetric environment, the system becomes bistable in its electronic configuration at a certain number of electrons. Under such a condition, the persistent current has a nonzero value even at an (almost) zero applied Aharonov-Bohm flux and results in very high magnetic susceptibility dM/dH at small nonzero fields, followed by an oscillatory dependence at larger fields. We tentatively assume that previously observed oscillatory magnetization in cyclic metallo-organic molecules by Gatteschi et al. can be attributed to persistent currents. If this proves correct, it may present an opportunity for (and, more generally, macromolecular cyclic structures may suggest the possibility of) engineering quantum computational tools based on the Aharonov-Bohm effect in ballistic nanostructures and macromolecular cyclic aggregates.

Tire-derived carbon composite anodes for sodium-ion batteries

DOE PAGES

Li, Yunchao; Paranthaman, M. Parans; Akato, Kokouvi; ...

2016-04-04

We report that hard-carbon materials are considered as one of the most promising anodes for the emerging sodium-ion batteries. Here, we report a low-cost, scalable waste tire-derived carbon as an anode for sodium-ion batteries (SIBs). The tire-derived carbons obtained by pyrolyzing the acid-treated tire at 1100 °C, 1400 °C and 1600 °C show capacities of 179, 185 and 203 mAh g -1, respectively, after 100 cycles at a current density of 20 mA g -1 in sodium-ion batteries with good electrochemical stability. The portion of the low-voltage plateau region in the charge-discharge curves increases as the heat-treatment temperature increases. Themore » low-voltage plateau is beneficial to enhance the energy density of the full cell. However, this plateau suffers rapid capacity fade at higher current densities. This study provides a new pathway for inexpensive, environmentally benign and value-added waste tire-derived products towards large-scale energy storage applications.« less

Potassium Loss during Galvanotaxis of Slime Mold

PubMed Central

Anderson, John D.

1962-01-01

The posterior reticulated regions of the plasmodia of the slime mold, Physarum polycephalum, whose migration has been oriented by direct current (3.0 to 5.0 µa/mm2 in the agar substrate), contain 30 per cent less potassium than the advancing non-reticulated region. The anterior regions have the same potassium concentration as that of the controls, approximately 32 meq/kg wet weight. Differences in potassium concentration between anterior and posterior regions of control plasmodia, not oriented by electric current, are less than 5 per cent. Sodium, in contrast to potassium, is generally less concentrated in the anterior than in the posterior regions of electrically oriented plasmodia, but sodium concentrations are extremely variable. No significant difference in protein concentration was found between oriented and control plasmodia. Thirty-five per cent of the total potassium, but none of the sodium, is found in acidified ethanol precipitates from plasmodial homogenates. Potassium, but not sodium, appears to be closely associated with processes which differentiate anterior from posterior in an oriented plasmodium. PMID:13861244

Voltage-Clamp Studies on Uterine Smooth Muscle

PubMed Central

Anderson, Nels C.

1969-01-01

These studies have developed and tested an experimental approach to the study of membrane ionic conductance mechanisms in strips of uterine smooth muscle. The experimental and theoretical basis for applying the double sucrose-gap technique is described along with the limitations of this system. Nonpropagating membrane action potentials were produced in response to depolarizing current pulses under current-clamp conditions. The stepwise change of membrane potential under voltage-clamp conditions resulted in a family of ionic currents with voltage- and time-dependent characteristics. In sodium-free solution the peak transient current decreased and its equilibrium potential shifted along the voltage axis toward a more negative internal potential. These studies indicate a sodium-dependent, regenerative excitation mechanism. PMID:5796366

Review: the use of sodium hypochlorite in endodontics--potential complications and their management.

PubMed

Spencer, H R; Ike, V; Brennan, P A

2007-05-12

Aqueous sodium hypochlorite (bleach) solution is widely used in dental practice during root canal treatment. Although it is generally regarded as being very safe, potentially severe complications can occur when it comes into contact with soft tissue. This paper discusses the use of sodium hypochlorite in dental treatment, reviews the current literature regarding hypochlorite complications, and considers the appropriate management for a dental practitioner when faced with a potentially adverse incident with this agent.

PERSISTENT CURRENT EFFECT IN 15-16 T NB3SN ACCELERATOR DIPOLES AND ITS CORRECTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashikhin, V. V.; Zlobin, A. V.

2016-11-08

Nb3Sn magnets with operating fields of 15-16 T are considered for the LHC Energy Doubler and a future Very High Energy pp Collider. Due to large coil volume, high critical current density and large superconducting (SC) filament size the persistent current effect is very large in Nb3Sn dipoles al low fields. This paper presents the results of analysis of the persistent current effect in the 15 T Nb3Sn dipole demonstrator being developed at FNAL, and describes different possibilities of its correction including passive SC wires, iron shims and coil geometry.

Red Phosphorus Nanodots on Reduced Graphene Oxide as a Flexible and Ultra-Fast Anode for Sodium-Ion Batteries.

PubMed

Liu, Yihang; Zhang, Anyi; Shen, Chenfei; Liu, Qingzhou; Cao, Xuan; Ma, Yuqiang; Chen, Liang; Lau, Christian; Chen, Tian-Chi; Wei, Fei; Zhou, Chongwu

2017-06-27

Sodium-ion batteries offer an attractive option for potential low cost and large scale energy storage due to the earth abundance of sodium. Red phosphorus is considered as a high capacity anode for sodium-ion batteries with a theoretical capacity of 2596 mAh/g. However, similar to silicon in lithium-ion batteries, several limitations, such as large volume expansion upon sodiation/desodiation and low electronic conductance, have severely limited the performance of red phosphorus anodes. In order to address the above challenges, we have developed a method to deposit red phosphorus nanodots densely and uniformly onto reduced graphene oxide sheets (P@RGO) to minimize the sodium ion diffusion length and the sodiation/desodiation stresses, and the RGO network also serves as electron pathway and creates free space to accommodate the volume variation of phosphorus particles. The resulted P@RGO flexible anode achieved 1165.4, 510.6, and 135.3 mAh/g specific charge capacity at 159.4, 31878.9, and 47818.3 mA/g charge/discharge current density in rate capability test, and a 914 mAh/g capacity after 300 deep cycles in cycling stability test at 1593.9 mA/g current density, which marks a significant performance improvement for red phosphorus anodes for sodium-ion chemistry and flexible power sources for wearable electronics.

The persistent current and energy spectrum on a driven mesoscopic LC-circuit with Josephson junction

NASA Astrophysics Data System (ADS)

Pahlavanias, Hassan

2018-03-01

The quantum theory for a mesoscopic electric circuit including a Josephson junction with charge discreteness is studied. By considering coupling energy of the mesoscopic capacitor in Josephson junction device, a Hamiltonian describing the dynamics of a quantum mesoscopic electric LC-circuit with charge discreteness is introduced. We first calculate the persistent current on a quantum driven ring including Josephson junction. Then we obtain the persistent current and energy spectrum of a quantum mesoscopic electrical circuit which includes capacitor, inductor, time-dependent external source and Josephson junction.

Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report

PubMed Central

2016-01-01

This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician’s diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC). A patch test using the toothpaste containing sodium lauryl sulfate (SLS) was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case. PMID:27789914

Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report.

PubMed

Thongprasom, Kobkan

2016-06-01

This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician's diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC). A patch test using the toothpaste containing sodium lauryl sulfate (SLS) was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case.

Pulsed magnetic stimulation modifies amplitude of action potentials in vitro via ionic channels-dependent mechanism.

PubMed

Ahmed, Zaghloul; Wieraszko, Andrzej

2015-07-01

This paper investigates the influence of pulsed magnetic fields (PMFs) on amplitude of evoked, compound action potential (CAP) recorded from the segments of sciatic nerve in vitro. PMFs were applied for 30 min at frequency of 0.16 Hz and intensity of 15 mT. In confirmation of our previous reports, PMF exposure enhanced amplitude of CAPs. The effect persisted beyond PMF activation period. As expected, CAP amplitude was attenuated by antagonists of sodium channel, lidocaine, and tetrodotoxin. Depression of the potential by sodium channels antagonists was reversed by subsequent exposure to PMFs. The effect of elevated potassium concentration and veratridine on the action potential was modified by exposure to PMFs as well. Neither inhibitors of protein kinase C and protein kinase A, nor known free radicals scavengers had any effects on PMF action. Possible mechanisms of PMF action are discussed. © 2015 Wiley Periodicals, Inc.

Prolonged hypernatremia triggered by hyperglycemic hyperosmolar state with coma: A case report.

PubMed

Vigil, Darlene; Ganta, Kavitha; Sun, Yijuan; Dorin, Richard I; Tzamaloukas, Antonios H; Servilla, Karen S

2015-05-06

A man with past lithium use for more than 15 years, but off lithium for two years and not carrying the diagnosis of diabetes mellitus or nephrogenic diabetes insipidus (NDI), presented with coma and hyperglycemic hyperosmolar state (HHS). Following correction of HHS, he developed persistent hypernatremia accompanied by large volumes of urine with low osmolality and no response to desmopressin injections. Urine osmolality remained < 300 mOsm/kg after injection of vasopressin. Improvement in serum sodium concentration followed the intake of large volumes of water plus administration of amiloride and hydrochlorothiazide. Severe hyperglycemia may trigger symptomatic lithium-induced NDI years after cessation of lithium therapy. Patients with new-onset diabetes mellitus who had been on prolonged lithium therapy in the past require monitoring of their serum sodium concentration after hyperglycemic episodes regardless of whether they do or do not carry the diagnosis of NDI.

Prolonged hypernatremia triggered by hyperglycemic hyperosmolar state with coma: A case report

PubMed Central

Vigil, Darlene; Ganta, Kavitha; Sun, Yijuan; Dorin, Richard I; Tzamaloukas, Antonios H; Servilla, Karen S

2015-01-01

A man with past lithium use for more than 15 years, but off lithium for two years and not carrying the diagnosis of diabetes mellitus or nephrogenic diabetes insipidus (NDI), presented with coma and hyperglycemic hyperosmolar state (HHS). Following correction of HHS, he developed persistent hypernatremia accompanied by large volumes of urine with low osmolality and no response to desmopressin injections. Urine osmolality remained < 300 mOsm/kg after injection of vasopressin. Improvement in serum sodium concentration followed the intake of large volumes of water plus administration of amiloride and hydrochlorothiazide. Severe hyperglycemia may trigger symptomatic lithium-induced NDI years after cessation of lithium therapy. Patients with new-onset diabetes mellitus who had been on prolonged lithium therapy in the past require monitoring of their serum sodium concentration after hyperglycemic episodes regardless of whether they do or do not carry the diagnosis of NDI. PMID:25949947

Fireball Observations in Visible and Sodium Bands

NASA Astrophysics Data System (ADS)

Fletcher, Sandra

On November 17th at 1:32am MST, a large Leonid fireball was simultaneously imaged by two experiments, a visible band CCD camera and a 590nm filtered band equi-angle fisheye and telecentric lens assembly. The visible band camera, ROTSE (Robotic Optical Transient Search Experiment) is a two by two f/1.9 telephoto lens array with 2k x2k Thompson CCD and is located at 35.87 N, 106.25 W at an altitude of 2115m. One-minute exposures along the radiant were taken of the event for 30 minutes after the initial explosion. The sodium band experiment was located at 35.29 N,106.46 W at an altitude of 1860m. It took ninety second exposures and captured several events throughout the night. Triangulation from two New Mexico sites resulted in an altitude of 83km over Wagon Mound, NM. Two observers present at the ROTSE site saw a green flash and a persistent glow up to seven minutes after the explosion. Cataloging of all sodium trails for comparison with lidar and infrasonic measurements is in progress. The raw data from both experiments and the atmospheric chemistry interpretation of them will be presented.

When to increase or reduce sodium loading in the management of fluid volume status during acute decompensated heart failure.

PubMed

Hirotani, Shinichi; Masuyama, Tohru

2014-12-01

Sodium restriction has been believed to be indispensible to manage fluid overload during acute decompensated heart failure (ADHF). However, recently, it was reported that a change in aggression of sodium and water restriction did not affect the outcome of ADHF. In contrast, current data suggest that small amount of hypertonic saline solution with high-dose furosemide produces an improvement in haemodynamic and clinical parameters without any severe adverse effects. In this perspective, first, we are going to describe the effects of sodium loading on neurohormonal activation, body's sodium balance, and renal function in chronic heart failure and the efficacy of loop diuretics in ADHF. Then, we are going to explain the possible mechanisms by which sodium loading enhances the efficacy of loop diuretics and about the clinical conditions during which sodium loading should be avoided. © 2014 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

New bimetallic EMF cell shows promise in direct energy conversion

NASA Technical Reports Server (NTRS)

Hesson, J. C.; Shimotake, H.

1968-01-01

Concentration cell, based upon a thermally regenerative cell principle, produces electrical energy from any large heat source. This experimental bimetallic EMF cell uses a sodium-bismuth alloy cathode and a pure liquid sodium anode. The cell exhibits reliability, corrosion resistance, and high current density performance.

Persistent oral human papillomavirus infection is associated with smoking and elevated salivary immunoglobulin G concentration.

PubMed

Haukioja, Anna; Asunta, Maribel; Söderling, Eva; Syrjänen, Stina

2014-09-01

Prevalence and risk factors for human papillomavirus (HPV) persistence in oral mucosa are largely unknown. Furthermore, the antiviral effects of saliva in the outcome of oral HPV infections are unexplored. To compare the levels of selected salivary defence proteins in women with a persistent oral HPV infection and in those without any signs of oral HPV. Lifestyle factors including the use of oral contraceptives, oral sex, smoking and alcohol drinking habits were also assessed. This nested case-control study of the Finnish Family HPV Study included 60 women with a persistent oral HPV infection and 117 women who remained HPV DNA negative throughout a 6-year follow-up. Whole saliva samples and oral scrapings for HPV testing were collected at the same visit. The oral HPV status was related to salivary concentrations of lactoferrin, lysozyme, IgA, IgG, total protein and sodium as well as to the use of oral contraceptives, oral sex, smoking and alcohol drinking habits. Women with a persistent oral HPV infection had higher salivary levels of IgG (p=0.007) and lysozyme (p=0.002, when adjusted to the total protein concentration), than those without an HPV infection. Lactoferrin and IgA concentrations were not related to the HPV-status. Smoking increased the risk of a persistent oral HPV infection (p=0.020), but the oral HPV status was not related to other life-style factors studied. Smoking is a risk factor for a persistent oral HPV infection. Oral HPV infection may be associated with increased concentrations of salivary IgG and lysozyme. Copyright © 2014 Elsevier B.V. All rights reserved.

Elesclomol Sodium and Paclitaxel in Treating Patients With Recurrent or Persistent Ovarian Epithelial Cancer, Fallopian Tube Cancer, or Primary Peritoneal Cancer

ClinicalTrials.gov

2017-05-02

Fallopian Tube Clear Cell Adenocarcinoma; Fallopian Tube Endometrioid Adenocarcinoma; Fallopian Tube Mucinous Adenocarcinoma; Fallopian Tube Serous Adenocarcinoma; Fallopian Tube Transitional Cell Carcinoma; Ovarian Brenner Tumor; Ovarian Clear Cell Adenocarcinoma; Ovarian Endometrioid Adenocarcinoma; Ovarian Mucinous Adenocarcinoma; Ovarian Seromucinous Carcinoma; Ovarian Serous Adenocarcinoma; Ovarian Transitional Cell Tumor; Primary Peritoneal Serous Adenocarcinoma; Recurrent Fallopian Tube Carcinoma; Recurrent Ovarian Carcinoma; Recurrent Primary Peritoneal Carcinoma; Undifferentiated Fallopian Tube Carcinoma; Undifferentiated Ovarian Carcinoma

Characteristics of persistent spin current components in a quasi-periodic Fibonacci ring with spin–orbit interactions: Prediction of spin–orbit coupling and on-site energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patra, Moumita; Maiti, Santanu K., E-mail: santanu.maiti@isical.ac.in

In the present work we investigate the behavior of all three components of persistent spin current in a quasi-periodic Fibonacci ring subjected to Rashba and Dresselhaus spin–orbit interactions. Analogous to persistent charge current in a conducting ring where electrons gain a Berry phase in presence of magnetic flux, spin Berry phase is associated during the motion of electrons in presence of a spin–orbit field which is responsible for the generation of spin current. The interplay between two spin–orbit fields along with quasi-periodic Fibonacci sequence on persistent spin current is described elaborately, and from our analysis, we can estimate the strengthmore » of any one of two spin–orbit couplings together with on-site energy, provided the other is known. - Highlights: • Determination of Rashba and Dresselhaus spin–orbit fields is discussed. • Characteristics of all three components of spin current are explored. • Possibility of estimating on-site energy is given. • Results can be generalized to any lattice models.« less

Desmopressin to Prevent Rapid Sodium Correction in Severe Hyponatremia: A Systematic Review.

PubMed

MacMillan, Thomas E; Tang, Terence; Cavalcanti, Rodrigo B

2015-12-01

Hyponatremia is common among inpatients and is associated with severe adverse outcomes such as osmotic demyelination syndrome. Current guidelines recommend serum sodium concentration correction targets of no more than 8 mEq/L per day in patients at high risk of osmotic demyelination syndrome. Desmopressin is recommended to control high rates of serum sodium concentration correction in severe hyponatremia. However, recommendations are based on limited data. The objective of this study is to review current strategies for DDAVP use in severe hyponatremia. Systematic literature search of 4 databases of peer-reviewed studies was performed and study quality was appraised. The literature search identified 17 observational studies with 80 patients. We found 3 strategies for desmopressin administration in hyponatremia: 1) proactive, where desmopressin is administered early based on initial serum sodium concentration; 2) reactive, where desmopressin is administered based on changes in serum sodium concentration or urine output; 3) rescue, where desmopressin is administered after serum sodium correction targets are exceeded or when osmotic demyelination appears imminent. A proactive strategy of desmopressin administration with hypertonic saline was associated with lower incidence of exceeding serum sodium concentration correction targets, although this evidence is derived from a small case series. Three distinct strategies for desmopressin administration are described in the literature. Limitations in study design and sample size prevent definitive conclusions about the optimal strategy for desmopressin administration to correct hyponatremia. There is a pressing need for better quality research to guide clinicians in managing severe hyponatremia. Copyright © 2015 Elsevier Inc. All rights reserved.

Differences in sodium voltage-gated channel properties according to myosin heavy chain isoform expression in single muscle fibres.

PubMed

Rannou, F; Droguet, M; Giroux-Metges, M A; Pennec, Y; Gioux, M; Pennec, J P

2009-11-01

The myosin heavy chain (MHC) isoform determines the characteristics and shortening velocity of muscle fibres. The functional properties of the muscle fibre are also conditioned by its membrane excitability through the electrophysiological properties of sodium voltage-gated channels. Macropatch-clamp is used to study sodium channels in fibres from peroneus longus (PL) and soleus (Sol) muscles (Wistar rats, n = 8). After patch-clamp recordings, single fibres are identified by SDS-PAGE electrophoresis according to their myosin heavy chain isoform (slow type I and the three fast types IIa, IIx, IIb). Characteristics of sodium currents are compared (Student's t test) between fibres exhibiting only one MHC isoform. Four MHC isoforms are identified in PL and only type I in Sol single fibres. In PL, maximal sodium current (I(max)), maximal sodium conductance (g(Na,max)) and time constants of activation and inactivation ((m) and (h)) increase according to the scheme I-->IIa-->IIx-->IIb (P < 0.05). (m) values related to sodium channel type and/or function, are similar in Sol I and PL IIb fibres (P = 0.97) despite different contractile properties. The voltage dependence of activation (V(a,1/2)) shows a shift towards positive potentials from Sol type I to IIa, IIx and finally IIb fibres from PL (P < 0.05). These data are consistent with the earlier recruitment of slow fibres in a fast-mixed muscle like PL, while slow fibres of postural muscle such as soleus could be recruited in the same ways as IIb fibres in a fast muscle.

Laser transmitter for space-based sodium lidar instrument

NASA Astrophysics Data System (ADS)

Yu, Anthony W.; Krainak, Michael A.; Janches, Diego; Konoplev, Oleg

2016-05-01

We are currently developing a laser transmitter to remotely measure Sodium (Na) by adapting existing lidar technology with space flight heritage. The developed instrumentation will serve as the core for the planning of a Heliophysics mission targeted to study the composition and dynamics of Earth's mesosphere based on a spaceborne lidar that will measure the mesospheric Na layer. We present performance results from our laser transmitter development effort with emphasis on wavelength tuning and power scaling of a diode-pumped Q-switched self-Raman c-cut Nd:YVO4 laser with intra-cavity frequency doubling that could produce multi-watt 589 nm wavelength output. We will review technologies that provide strong leverage for the sodium lidar laser system with strong heritage from past and current space flight missions.

Collecting Duct Nitric Oxide Synthase 1ß Activation Maintains Sodium Homeostasis During High Sodium Intake Through Suppression of Aldosterone and Renal Angiotensin II Pathways.

PubMed

Hyndman, Kelly A; Mironova, Elena V; Giani, Jorge F; Dugas, Courtney; Collins, Jessika; McDonough, Alicia A; Stockand, James D; Pollock, Jennifer S

2017-10-24

During high sodium intake, the renin-angiotensin-aldosterone system is downregulated and nitric oxide signaling is upregulated in order to remain in sodium balance. Recently, we showed that collecting duct nitric oxide synthase 1β is critical for fluid-electrolyte balance and subsequently blood pressure regulation during high sodium feeding. The current study tested the hypothesis that high sodium activation of the collecting duct nitric oxide synthase 1β pathway is critical for maintaining sodium homeostasis and for the downregulation of the renin-angiotensin-aldosterone system-epithelial sodium channel axis. Male control and collecting duct nitric oxide synthase 1β knockout (CDNOS1KO) mice were placed on low, normal, and high sodium diets for 1 week. In response to the high sodium diet, plasma sodium was significantly increased in control mice and to a significantly greater level in CDNOS1KO mice. CDNOS1KO mice did not suppress plasma aldosterone in response to the high sodium diet, which may be partially explained by increased adrenal AT1R expression. Plasma renin concentration was appropriately suppressed in both genotypes. Furthermore, CDNOS1KO mice had significantly higher intrarenal angiotensin II with high sodium diet, although intrarenal angiotensinogen levels and angiotensin-converting enzyme activity were similar between knockout mice and controls. In agreement with inappropriate renin-angiotensin-aldosterone system activation in the CDNOS1KO mice on a high sodium diet, epithelial sodium channel activity and sodium transporter abundance were significantly higher compared with controls. These data demonstrate that high sodium activation of collecting duct nitric oxide synthase 1β signaling induces suppression of systemic and intrarenal renin-angiotensin-aldosterone system, thereby modulating epithelial sodium channel and other sodium transporter abundance and activity to maintain sodium homeostasis. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Octopamine increases the excitability of neurons in the snail feeding system by modulation of inward sodium current but not outward potassium currents.

PubMed

Vehovszky, Agnes; Szabó, Henriette; Elliott, Christopher J H

2005-12-06

Although octopamine has long been known to have major roles as both transmitter and modulator in arthropods, it has only recently been shown to be functionally important in molluscs, playing a role as a neurotransmitter in the feeding network of the snail Lymnaea stagnalis. The synaptic potentials cannot explain all the effects of octopamine-containing neurons on the feeding network, and here we test the hypothesis that octopamine is also a neuromodulator. The excitability of the B1 and B4 motoneurons in the buccal ganglia to depolarising current clamp pulses is significantly (P < < 0.05) increased by (10 microM) octopamine, whereas the B2 motoneuron becomes significantly less excitable. The ionic currents evoked by voltage steps were recorded using 2-electrode voltage clamp. The outward current of B1, B2 and B4 motoneurons had two components, a transient IA current and a sustained IK delayed-rectifier current, but neither was modulated by octopamine in any of these three buccal neurons. The fast inward current was eliminated in sodium-free saline and so is likely to be carried by sodium ions. 10 microM octopamine enhanced this current by 33 and 45% in the B1 and B4 motoneurons respectively (P < < 0.05), but a small reduction was seen in the B2 neuron. A Hodgkin-Huxley style simulation of the B1 motoneuron confirms that a 33% increase in the fast inward current by octopamine increases the excitability markedly. We conclude that octopamine is also a neuromodulator in snails, changing the excitability of the buccal neurons. This is supported by the close relationship from the voltage clamp data, through the quantitative simulation, to the action potential threshold, changing the properties of neurons in a rhythmic network. The increase in inward sodium current provides an explanation for the polycyclic modulation of the feeding system by the octopamine-containing interneurons, making feeding easier to initiate and making the feeding bursts more intense.

Adoptable Interventions, Human Health, and Food Safety Considerations for Reducing Sodium Content of Processed Food Products

PubMed Central

Allison, Abimbola; Fouladkhah, Aliyar

2018-01-01

Although vital for maintaining health when consumed in moderation, various epidemiological studies in recent years have shown a strong association between excess dietary sodium with an array of health complications. These associations are robust and clinically significant for development of hypertension and prehypertension, two of the leading causes of preventable mortality worldwide, in adults with a high-sodium diet. Data from developed nations and transition economies show worldwide sodium intake of higher than recommended amounts in various nations. While natural foods typically contain a moderate amount of sodium, manufactured food products are the main contributor to dietary sodium intake, up to 75% of sodium in diet of American adults, as an example. Lower cost in formulation, positive effects on organoleptic properties of food products, effects on food quality during shelf-life, and microbiological food safety, make sodium chloride a notable candidate and an indispensable part of formulation of various products. Although low-sodium formulation of each product possesses a unique set of challenges, review of literature shows an abundance of successful experiences for products of many categories. The current study discusses adoptable interventions for product development and reformulation of products to achieve a modest amount of final sodium content while maintaining taste, quality, shelf-stability, and microbiological food safety. PMID:29389843

Adoptable Interventions, Human Health, and Food Safety Considerations for Reducing Sodium Content of Processed Food Products.

PubMed

Allison, Abimbola; Fouladkhah, Aliyar

2018-02-01

Although vital for maintaining health when consumed in moderation, various epidemiological studies in recent years have shown a strong association between excess dietary sodium with an array of health complications. These associations are robust and clinically significant for development of hypertension and prehypertension, two of the leading causes of preventable mortality worldwide, in adults with a high-sodium diet. Data from developed nations and transition economies show worldwide sodium intake of higher than recommended amounts in various nations. While natural foods typically contain a moderate amount of sodium, manufactured food products are the main contributor to dietary sodium intake, up to 75% of sodium in diet of American adults, as an example. Lower cost in formulation, positive effects on organoleptic properties of food products, effects on food quality during shelf-life, and microbiological food safety, make sodium chloride a notable candidate and an indispensable part of formulation of various products. Although low-sodium formulation of each product possesses a unique set of challenges, review of literature shows an abundance of successful experiences for products of many categories. The current study discusses adoptable interventions for product development and reformulation of products to achieve a modest amount of final sodium content while maintaining taste, quality, shelf-stability, and microbiological food safety.

Effect of stimulation and hyperpolarization on non-electrolyte and sodium permeability in perfused axons of squid.

PubMed

Hidalgo, C; Latorre, R

1970-11-01

1. The permeability for micro-injected [(3)H]ethylene glycol was measured in resting state and during stimulation at 100/sec in squid giant axons. No detectable changes during electrical activity were observed.2. The influxes of urethane, tritiated water, ethylene glycol, urea and sodium were measured in internally perfused squid axons. Ethylene glycol and urea influxes were determined simultaneously with sodium influxes. The electrical stimulation of the fibre produced an increase in the influx of sodium but did not alter the influxes of the non-electrolytes listed above.3. Experiments were done with the combined voltage clamp-perfusion technique. The influxes of ethylene glycol and sodium were simultaneously measured in resting state and during maximum sodium current under stimulation at 10/sec. The influx of sodium increased in these conditions but the influx of ethylene glycol remained constant. In some experiments, the fibre was hyperpolarized to 10 or 20 mV, above the resting potential and the influxes of ethylene glycol and sodium were measured. The sodium influx decreased to 60% at 20 mV above the resting potential whereas the influx of ethylene glycol remained constant.4. These results indicate that in the giant axons of the squid Dosidicus gigas, sodium and non-electrolytes fluxes are not coupled.

Effect of stimulation and hyperpolarization on non-electrolyte and sodium permeability in perfused axons of squid

PubMed Central

Hidalgo, Cecilia; Latorre, Ramón

1970-01-01

1. The permeability for micro-injected [3H]ethylene glycol was measured in resting state and during stimulation at 100/sec in squid giant axons. No detectable changes during electrical activity were observed. 2. The influxes of urethane, tritiated water, ethylene glycol, urea and sodium were measured in internally perfused squid axons. Ethylene glycol and urea influxes were determined simultaneously with sodium influxes. The electrical stimulation of the fibre produced an increase in the influx of sodium but did not alter the influxes of the non-electrolytes listed above. 3. Experiments were done with the combined voltage clamp—perfusion technique. The influxes of ethylene glycol and sodium were simultaneously measured in resting state and during maximum sodium current under stimulation at 10/sec. The influx of sodium increased in these conditions but the influx of ethylene glycol remained constant. In some experiments, the fibre was hyperpolarized to 10 or 20 mV, above the resting potential and the influxes of ethylene glycol and sodium were measured. The sodium influx decreased to 60% at 20 mV above the resting potential whereas the influx of ethylene glycol remained constant. 4. These results indicate that in the giant axons of the squid Dosidicus gigas, sodium and non-electrolytes fluxes are not coupled. PMID:5500991

Early adulthood: an overlooked age group in national sodium reduction initiatives in South Korea.

PubMed

Park, Sohyun; Lee, Jounghee; Kwon, Kwang-Il; Kim, Jong-Wook; Byun, Jae-Eon; Kang, Baeg-Won; Choi, Bo Youl; Park, Hye-Kyung

2014-12-01

South Korean's sodium consumption level is more than twice the upper limit level suggested by the WHO. Steep increases in the prevalence of hypertension and cardiovascular disease in Korea necessitate more effective sodium reduction programs. This study was conducted in order to compare sodium intake-related eating behaviors and key psychosocial factors according to age group and gender. Using an online survey, a total of 1,564 adults (20-59 years old) considered to be geographically representative of South Korea were recruited and surveyed. The major outcomes were perceived behaviors, knowledge, intentions, and self-efficacy related to sodium intake. The results show that perceived behavior and level of self-efficacy related to low sodium consumption differed by age and gender. Female participants showed better behavior and intention towards low sodium intake than male counterparts. Young participants in their 20s showed the lowest intention to change their current sodium intake as well as lowest self-efficacy measures. Future sodium reduction interventions should be developed with tailored messages targeting different age and gender groups. Specifically, interventions can be planned and implemented at the college level or for workers in their early career to increase their intention and self-efficacy as a means of preventing future health complications associated with high sodium intake.

Characterization of TTX-sensitive and TTX-resistant sodium currents in small cells from adult rat dorsal root ganglia.

PubMed

Elliott, A A; Elliott, J R

1993-04-01

1. The whole-cell patch-clamp technique was used to investigate the characteristics of two types of sodium current (INa) recorded at room temperature from small diameter (13-25 microns) dorsal root ganglion (DRG) cells, isolated from adult rats and maintained overnight in culture. 2. Sodium currents were isolated pharmacologically. Internal Cs+ and external tetraethylammonium (TEA) ions were used to suppress potassium currents. A combination of internal EGTA, internal F-, a low (10 microM) concentration of external Ca2+ and a relatively high (5 mM) concentration of internal and external Mg2+ was used to block calcium channels. The remaining voltage-dependent currents reversed direction at the calculated sodium equilibrium potential. Both the reversal potential and magnitude of the currents exhibited the expected dependence on the external sodium concentration. 3. INa subtypes were characterized initially in terms of their sensitivity to tetrodotoxin (TTX). TTX-sensitive (TTXs) currents were at least 97% suppressed by 0.1 microM TTX. TTX-resistant (TTXr) INa were recorded in the presence of 0.3 microM TTX and appeared to be reduced in amplitude by less than 50% in 75 microM TTX (n = 1). 4. As in earlier studies, the peak of the current-voltage relationship, the mid-point of the normalized conductance curve and the potential (Vh) at which the steady-state inactivation parameter (h infinity) was 0.5 were found to be significantly more depolarized for the TTXr INa (by ca 10, 14 and 37 mV respectively). There was little difference in the slope at the mid-point of the normalized conductance curves (the mean slope factors were 5.1 mV for the TTXs INa and 4.9 mV for the TTXr current) but the h infinity curves for TTXr currents were significantly steeper than those for TTXs currents (mean slope factors of 3.8 and 11.5 mV respectively). Both the time to peak and the decay time constant of the peak current recorded from a holding potential of -67 mV were more than a factor of three slower for the TTXr INa than for the TTXs current. 5. However, in direct contrast to the difference in activation and decay kinetics, 'slow' TTXr INa recovered from inactivation at -67mV, or reprimed, more than a factor of ten faster than 'fast' TTXs INa. 6. The differences apparent in both the repriming kinetics of TTXs and TTXr INa at -67 mV and the kinetics of the decay phase of the peak INa are shown to be explicable largely in terms of the voltage dependence of their respective inactivation systems.(ABSTRACT TRUNCATED AT 400 WORDS)

Eslicarbazepine acetate for the treatment of focal epilepsy: an update on its proposed mechanisms of action

PubMed Central

Soares-da-Silva, Patrício; Pires, Nuno; Bonifácio, Maria João; Loureiro, Ana I; Palma, Nuno; Wright, Lyndon C

2015-01-01

Eslicarbazepine acetate (ESL) is a once daily antiepileptic drug (AED) approved by the European Medicines Agency (EMA), the Food and Drug Administration (FDA) and Health Canada as an adjunctive therapy in adults with partial-onset seizures (POS). In humans and in relevant animal laboratory species, ESL undergoes extensive first pass hydrolysis to its major active metabolite eslicarbazepine that represents ∼95% of circulating active moieties. ESL and eslicarbazepine showed anticonvulsant activity in animal models. ESL may not only suppress seizure activity but may also inhibit the generation of a hyperexcitable network. Data reviewed here suggest that ESL and eslicarbazepine demonstrated the following in animal models: (1) the selectivity of interaction with the inactive state of the voltage-gated sodium channel (VGSC), (2) reduction in VGSC availability through enhancement of slow inactivation, instead of alteration of fast inactivation of VGSC, (3) the failure to cause a paradoxical upregulation of persistent Na+ current (INaP), and (4) the reduction in firing frequencies of excitatory neurons in dissociated hippocampal cells from patients with epilepsy who were pharmacoresistant to carbamazepine (CBZ). In addition, eslicarbazepine effectively inhibited high- and low-affinity hCaV3.2 inward currents with greater affinity than CBZ. These preclinical findings may suggest the potential for antiepileptogenic effects; furthermore, the lack of effect upon KV7.2 outward currents may translate into a reduced potential for eslicarbazepine to facilitate repetitive firing. PMID:26038700

Sodium fluoride in otosclerosis treatment: review.

PubMed

Cruise, A S; Singh, A; Quiney, R E

2010-06-01

To review the current literature on the use of sodium fluoride in the treatment of otosclerosis. A literature review was conducted, searching the Medline and PubMed database from 1966 to 2009, using the terms 'otosclerosis' and 'fluoride'. Article abstracts were reviewed and relevant full articles acquired. There has been only one double-blind, placebo-controlled trial of the use of sodium fluoride in otosclerosis patients, and this found a reduced incidence of deterioration in hearing after two years in the treatment group. Several case-control series have described a hearing benefit in the sodium fluoride treated group. Treatment doses vary greatly, and there is no evidence regarding the optimum duration of treatment. There is low quality evidence suggesting that sodium fluoride may be of benefit to preserve hearing and reduce vestibular symptoms in patients with otosclerosis.

Use of Electrochemical Noise (EN) Technique to Study the Effect of sulfate and Chloride Ions on Passivation and Pitting Corrosion Behavior of 316 Stainless Steel

NASA Astrophysics Data System (ADS)

Pujar, M. G.; Anita, T.; Shaikh, H.; Dayal, R. K.; Khatak, H. S.

2007-08-01

In the present paper, studies were conducted on AISI Type 316 stainless steel (SS) in deaerated solutions of sodium sulfate as well as sodium chloride to establish the effect of sulfate and chloride ions on the electrochemical corrosion behavior of the material. The experiments were conducted in deaerated solutions of 0.5 M sodium sulfate as well as 0.5 M sodium chloride using electrochemical noise (EN) technique at open circuit potential (OCP) to collect the correlated current and potential signals. Visual records of the current and potential, analysis of data to arrive at the statistical parameters, spectral density estimation using the maximum entropy method (MEM) showed that sulfate ions were incorporated in the passive film to strengthen the same. However, the adsorption of chloride ions resulted in pitting corrosion thereby adversely affecting noise resistance ( R N). Distinct current and potential signals were observed for metastable pitting, stable pitting and passive film build-up. Distinct changes in the values of the statistical parameters like R N and the spectral noise resistance at zero frequency ( R°SN) revealed adsorption and incorporation of sulfate and chloride ions on the passive film/solution interface.

Inhibition of cardiac sodium currents by toluene exposure

PubMed Central

Cruz, Silvia L; Orta-Salazar, Gerardo; Gauthereau, Marcia Y; Millan-Perez Peña, Lourdes; Salinas-Stefanón, Eduardo M

2003-01-01

Toluene is an industrial solvent widely used as a drug of abuse, which can produce sudden sniffing death due to cardiac arrhythmias. In this paper, we tested the hypothesis that toluene inhibits cardiac sodium channels in Xenopus laevis oocytes transfected with Nav1.5 cDNA and in isolated rat ventricular myocytes. In oocytes, toluene inhibited sodium currents (INa+) in a concentration-dependent manner, with an IC50 of 274 μM (confidence limits: 141–407μM). The inhibition was complete, voltage-independent, and slowly reversible. Toluene had no effect on: (i) the shape of the I–V curves; (ii) the reversal potential of Na+; and (iii) the steady-state inactivation. The slow recovery time constant from inactivation of INa+ decreased with toluene exposure, while the fast recovery time constant remained unchanged. Block of INa+ by toluene was use- and frequency-dependent. In rat cardiac myocytes, 300 μM toluene inhibited the sodium current (INa+) by 62%; this inhibition was voltage independent. These results suggest that toluene binds to cardiac Na+ channels in the open state and unbinds either when channels move between inactivated states or from an inactivated to a closed state. The use- and frequency-dependent block of INa+ by toluene might be responsible, at least in part, for its arrhythmogenic effect. PMID:14534149

Effect of cyclic aromatics on sodium active transport in frog skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blankemeyer, J.T.; Bowerman, M.C.

1993-01-01

A modified glass Ussing-chamber was used to mount the skin. The electrical potential difference (PD) was measured by two 3% agar-frog Ringer's bridges. Current (i.e. short-circuit current, or ISC) was passed by Ag-AgCl electrodes placed so that current density was uniform across the skin. Ringer's solution, bathing each side of the frog skin, was stirred and aerated by gas-lift pumps. The effect of toxicants on the ISC was determined by using the 15 min prior to toxicant administration as a control period, then calculating the change in ISC during the toxicant period as a percent of the control ISC. Phenolmore » and benzene are components of crude oil and crude oil waste. These hydrocarbons and phenanthrene were tested for their effect on frog skin. The results show that the effect of organics on sodium active transport of an epithelium is to alter the active transport of sodium ions. 5 refs., 3 figs., 1 tab.« less

Compendium of Dental Residents’ Research Project and Literature Reviews - 1991.

DTIC Science & Technology

1992-04-01

4-log1 0 (99.99%) reduction of any of the microorgan- isms under the test conditions. Sporicidin and 0.525% sodium hypochlorite were able to effect a...4-log1 0 reduction against S. aureus only. Impresept and 5.25% sodium hypochlorite did achieve a 4-log10 reduction in bacterial counts in all cases...alginate impressions is currently unknown and warrants investigation. Full strength (5.25%) sodium hypochlorite was effective in the shortest contact time (1

Urinary sodium excretion and kidney failure in non-diabetic chronic kidney disease

PubMed Central

Fan, Li; Tighiouart, Hocine; Levey, Andrew S.; Beck, Gerald J.; Sarnak, Mark J.

2014-01-01

Current guidelines recommend under 2g/day sodium intake in chronic kidney disease, but there are few studies relating sodium intake to long-term outcomes. Here we evaluated the association of mean baseline 24-hour urinary sodium excretion with kidney failure and a composite outcome of kidney failure or all-cause mortality using Cox regression in 840 participants enrolled in the Modification of Diet in Renal Disease Study. Mean 24-hour urinary sodium excretion was 3.46 g/day. Kidney failure developed in 617 and the composite outcome was reached in 723. In the primary analyses there was no association between 24-hour urine sodium and kidney failure [HR 0.99 (95% CI 0.91–1.08)] nor on the composite outcome [HR 1.01 (95% CI 0.93–1.09),] each per 1g/day higher urine sodium. In exploratory analyses there was a significant interaction of baseline proteinuria and sodium excretion with kidney failure. Using a 2-slope model, when urine sodium was under 3g/day, higher urine sodium was associated with increased risk of kidney failure in those with baseline proteinuria under 1g/day, and lower risk of kidney failure in those with baseline proteinuria of 1g/day or more. There was no association between urine sodium and kidney failure when urine sodium was 3g/day or more. Results were consistent using first baseline and time-dependent urine sodium. Thus, we noted no association of urine sodium with kidney failure. Results of the exploratory analyses need to be verified in additional studies and the mechanism explored. PMID:24646858

Indoxacarb, Metaflumizone, and Other Sodium Channel Inhibitor Insecticides: Mechanism and Site of Action on Mammalian Voltage-Gated Sodium Channels

PubMed Central

von Stein, Richard T.; Silver, Kristopher S.; Soderlund, David M.

2013-01-01

Sodium channel inhibitor (SCI) insecticides were discovered almost four decades ago but have only recently yielded important commercial products (eg., indoxacarb and metaflumizone). SCI insecticides inhibit sodium channel function by binding selectively to slow-inactivated (non-conducting) sodium channel states. Characterization of the action of SCI insecticides on mammalian sodium channels using both biochemical and electrophysiological approaches demonstrates that they bind at or near a drug receptor site, the "local anesthetic (LA) receptor." This mechanism and site of action on sodium channels differentiates SCI insecticides from other insecticidal agents that act on sodium channels. However, SCI insecticides share a common mode of action with drugs currently under investigation as anticonvulsants and treatments for neuropathic pain. In this paper we summarize the development of the SCI insecticide class and the evidence that this structurally diverse group of compounds have a common mode of action on sodium channels. We then review research that has used site-directed mutagenesis and heterologous expression of cloned mammalian sodium channels in Xenopus laevis oocytes to further elucidate the site and mechanism of action of SCI insecticides. The results of these studies provide new insight into the mechanism of action of SCI insecticides on voltage-gated sodium channels, the location of the SCI insecticide receptor, and its relationship to the LA receptor that binds therapeutic SCI agents. PMID:24072940

Gateways to clinical trials.

PubMed

Bayes, M; Rabasseda, X; Prous, J R

2002-05-01

Gateways to Clinical Trials is a guide to the most recent clinical trials in current literature and congresses. The data in the following tables can be retrieved from the Clinical Studies knowledge area of Prous Science Integrity, the drug discovery and development portal, http://integrity.prous.com. This issue focuses on the following selection of drugs: Abacavir sulfate, abarelix, abciximab, acarbose, alefacept, alteplase, amisulpride, amoxicillin trihydrate, apomorphine hydrochloride, aprepitant, argatroban monohydrate, aspirin, atenolol; Betamethasone dipropionate, betamethasone valerate, bicalutamide, bleomycin sulfate; Calcium carbonate, candesartan cilexetil, celecoxib, cetirizine hydrochloride, cisplatin, clarithromycin, clavulanate potassium, clomethiazole edisilate, clopidogrel hydrogensulfate, cyclophosphamide, chorionic gonadotropin (human); Dalteparin sodium, desloratadine, dexamethasone, doxorubicin, DPC-083; Efalizumab, efavirenz, enoxaparin sodium, eprosartan mesilate, etanercept, etoposide, ezetimibe; Faropenem daloxate, fenofibrate, fluocinolone acetonide, flutamide, fluvastatin sodium, follitropin beta, fondaparinux sodium; Gabapentin, glibenclamide, goserelin, granisetron hydrochloride; Haloperidol, hydrochlorothiazide; Imiquimod, interferon beta-1a, irbesartan, iseganan hydrochloride; L-758298, lamivudine, lanoteplase, leflunomide, leuprorelin acetate, loratadine, losartan potassium; Melagatran, metformin hydrochloride, methotrexate, metronidazole, micafungin sodium, mitoxantrone hydrochloride; Nelfinavir mesilate, neutral insulin injection, nizatidine; Olopatadine hydrochloride, omeprazole, ondansetron hydrochloride; Pamidronate sodium, paracetamol, paroxetine hydrochloride, perindopril, pimecrolimus, pioglitazone hydrochloride, piroxicam, pleconaril, pralmorelin, pravastatin sodium, prednisolone, prednisone, propofol; Raloxifene hydrochloride, ranpirnase, remifentanil hydrochloride, risedronate sodium, risperidone, rofecoxib, ropinirole hydrochloride, rosuvastatin calcium; Sevoflurane, sildenafil citrate, simvastatin, somatropin; Tacrolimus, tamoxifen citrate, telmisartan, temozolomide, thiopental sodium, tinzaparin sodium, tirofiban hydrochloride, treosulfan, triamcinolone acetonide; Urokinase; Valsartan, vardenafil, vincristine; Warfarin sodium; Ximelagatran; Zidovudine.

Ranolazine Shortens Repolarization in Patients with Sustained Inward Sodium Current Due To Type-3 Long QT Syndrome

PubMed Central

Moss, Arthur J.; Zareba, Wojciech; Schwarz, Karl Q.; Rosero, Spencer; McNitt, Scott; Robinson, Jennifer L.

2008-01-01

Introduction One form of the hereditary long QT-syndrome, LQT3-ΔKPQ, is associated with sustained inward sodium current during membrane depolarization. Ranolazine reduces late sodium channel current, and we hypothesized that ranolazine would have beneficial effects on electrical and mechanical cardiac function in LQT3 patients with the SCN5A-ΔKPQ mutation. Methods We assessed the effects of 8-hour intravenous ranolazine infusions (45mg/hr for 3 hours followed by 90mg/hr for 5 hours) on ventricular repolarization and myocardial relaxation in five LQT3 patients with the SCN5A-ΔKPQ mutation. Changes in electrocardiographic QTc parameters from before to during ranolazine infusion were evaluated by time-matched, paired t-test analyses. Cardiac ultrasound recordings were obtained before ranolazine infusion and just before completion of the 8-hour ranolazine infusion. Results Ranolazine shortened QTc by 26±3ms (p<0.0001) in a concentration-dependent manner. At peak ranolazine infusion, there was a significant 13% shortening in left ventricular isovolumic relaxation time, a significant 25% increase in mitral E-wave velocity, and a meaningful 22% decrease in mitral E-wave deceleration time compared to baseline. No adverse effects of ranolazine were observed in the study patients. Conclusion Ranolazine at therapeutic concentrations shortened a prolonged QTc interval and improved diastolic relaxation in patients with the LQT3-ΔKPQ mutation, a genetic disorder that is known to cause an increase of late sodium current. PMID:18662191

Effects of the β1 auxiliary subunit on modification of Rat Na{sub v}1.6 sodium channels expressed in HEK293 cells by the pyrethroid insecticides tefluthrin and deltamethrin

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Bingjun; Soderlund, David M., E-mail: dms6@cornell.edu

We expressed rat Na{sub v}1.6 sodium channels with or without the rat β1 subunit in human embryonic kidney (HEK293) cells and evaluated the effects of the pyrethroid insecticides tefluthrin and deltamethrin on whole-cell sodium currents. In assays with the Na{sub v}1.6 α subunit alone, both pyrethroids prolonged channel inactivation and deactivation and shifted the voltage dependence of channel activation and steady-state inactivation toward hyperpolarization. Maximal shifts in activation were ~ 18 mV for tefluthrin and ~ 24 mV for deltamethrin. These compounds also caused hyperpolarizing shifts of ~ 10–14 mV in the voltage dependence of steady-state inactivation and increased inmore » the fraction of sodium current that was resistant to inactivation. The effects of pyrethroids on the voltage-dependent gating greatly increased the size of sodium window currents compared to unmodified channels; modified channels exhibited increased probability of spontaneous opening at membrane potentials more negative than the normal threshold for channel activation and incomplete channel inactivation. Coexpression of Na{sub v}1.6 with the β1 subunit had no effect on the kinetic behavior of pyrethroid-modified channels but had divergent effects on the voltage-dependent gating of tefluthrin- or deltamethrin-modified channels, increasing the size of tefluthrin-induced window currents but decreasing the size of corresponding deltamethrin-induced currents. Unexpectedly, the β1 subunit did not confer sensitivity to use-dependent channel modification by either tefluthrin or deltamethrin. We conclude from these results that functional reconstitution of channels in vitro requires careful attention to the subunit composition of channel complexes to ensure that channels in vitro are faithful functional and pharmacological models of channels in neurons. - Highlights: • We expressed Na{sub v}1.6 sodium channels with or without β1 subunits in HEK293 cells. • Tefluthrin and deltamethrin shifted channel gating to hyperpolarized potentials. • The β1 subunit had opposite effects on the actions of tefluthrin and deltamethrin. • Auxiliary subunits are required for full reconstitution of channel function. • Channels in HEK293 cells exhibit properties similar to channels in neurons.« less

Severe hyperkalemia is rescued by low-potassium diet in renal βENaC-deficient mice.

PubMed

Boscardin, Emilie; Perrier, Romain; Sergi, Chloé; Maillard, Marc; Loffing, Johannes; Loffing-Cueni, Dominique; Koesters, Robert; Rossier, Bernard Claude; Hummler, Edith

2017-10-01

In adulthood, an induced nephron-specific deficiency of αENaC (Scnn1a) resulted in pseudohypoaldosteronism type 1 (PHA-1) with sodium loss, hyperkalemia, and metabolic acidosis that is rescued through high-sodium/low-potassium (HNa + /LK + ) diet. In the present study, we addressed whether renal βENaC expression is required for sodium and potassium balance or can be compensated by remaining (α and γ) ENaC subunits using adult nephron-specific knockout (Scnn1b Pax8/LC1 ) mice. Upon induction, these mice present a severe PHA-1 phenotype with weight loss, hyperkalemia, and dehydration, but unlike the Scnn1a Pax8/LC1 mice without persistent salt wasting. This is followed by a marked downregulation of STE20/SPS1-related proline-alanine-rich protein kinase (SPAK) and Na + /Cl - co-transporter (NCC) protein expression and activity. Most of the experimental Scnn1b Pax8/LC1 mice survived with a HNa + /LK + diet that partly normalized NCC phosphorylation, but not total NCC expression. Since salt loss was minor, we applied a standard-sodium/LK + diet that efficiently rescued these mice resulting in normokalemia and normalization of NCC phosphorylation, but not total NCC expression. A further switch to LNa + /standard-K + diet induced again a severe PHA-1-like phenotype, but with only transient salt wasting indicating that low-K + intake is critical to decrease hyperkalemia in a NCC-dependent manner. In conclusion, while the βENaC subunit plays only a minor role in sodium balance, severe hyperkalemia results in downregulation of NCC expression and activity. Our data demonstrate the importance to primarily correct the hyperkalemia with a low-potassium diet that normalizes NCC activity.

Cardiac sodium channel blockade after an intentional ingestion of lacosamide, cyclobenzaprine, and levetiracetam: Case report.

PubMed

Chua-Tuan, Jenny L; Cao, Dazhe; Iwanicki, Janetta L; Hoyte, Christopher O

2015-07-01

Lacosamide treats partial seizures by enhancing slow inactivation of voltage-gated sodium channels. The described cardiac toxicity of lacosamide in the literature to date includes atrioventricular blockade (PR prolongation), atrial flutter, atrial fibrillation, sinus pauses, ventricular tachycardia and a single cardiac arrest. We report a second case of cardiac arrest following an intentional lacosamide overdose. A 16 year-old female with a seizure disorder was found unresponsive in pulseless ventricular tachycardia after intentionally ingesting 4.5 g (76 mg/kg) lacosamide, 120 mg (2 mg/kg) cyclobenzaprine and an unknown amount of levetiracetam. Exact time of ingestion was unknown. Her initial electrocardiogram (ECG) demonstrated sinus tachycardia at 139 beats per minute, QRS duration 112 ms, and terminal R-wave in lead aVR > 3 mm. Despite treatment with 150 mEq of sodium bicarbonate, she had persistent EKG findings eight hours after presentation. Her serum lacosamide concentration nine hours after presentation was elevated at 22.8 μg/mL, while serum cyclobenzaprine concentration was 16 ng/mL (therapeutic: 10-30 ng/mL), and serum levetiracetam concentration was 22.7 μg/mL (therapeutic: 12-46 μg/mL). On hospital day three, ECG demonstrated resolution of the terminal R-wave with QRS of 78 ms. The patient recovered without physical or neurologic sequelae. The patient's lacosamide, cyclobenzaprine and levetiracetam overdose was associated with QRS prolongation and terminal right axis deviation--suggesting sodium channel blockade as a likely etiology for her cardiac arrest. Cyclobenzaprine has potential for sodium channel blockade and ventricular dysrhythmias although cardiac toxicity due to cyclobenzaprine alone is rare. The combination of cyclobenzaprine with lacosamide may have resulted in cardiovascular collapse. In conclusion, overdose of lacosamide combined with therapeutic concentrations of sodium channel blocking xenobiotics may cause cardiac conduction delays and cardiac arrest.

Sodium entry through endothelial store-operated calcium entry channels: regulation by Orai1

PubMed Central

Xu, Ningyong; Cioffi, Donna L.; Alexeyev, Mikhail; Rich, Thomas C.

2014-01-01

Orai1 interacts with transient receptor potential protein of the canonical subfamily (TRPC4) and contributes to calcium selectivity of the endothelial cell store-operated calcium entry current (ISOC). Orai1 silencing increases sodium permeability and decreases membrane-associated calcium, although it is not known whether Orai1 is an important determinant of cytosolic sodium transitions. We test the hypothesis that, upon activation of store-operated calcium entry channels, Orai1 is a critical determinant of cytosolic sodium transitions. Activation of store-operated calcium entry channels transiently increased cytosolic calcium and sodium, characteristic of release from an intracellular store. The sodium response occurred more abruptly and returned to baseline more rapidly than did the transient calcium rise. Extracellular choline substitution for sodium did not inhibit the response, although 2-aminoethoxydiphenyl borate and YM-58483 reduced it by ∼50%. After this transient response, cytosolic sodium continued to increase due to influx through activated store-operated calcium entry channels. The magnitude of this sustained increase in cytosolic sodium was greater when experiments were conducted in low extracellular calcium and when Orai1 expression was silenced; these two interventions were not additive, suggesting a common mechanism. 2-Aminoethoxydiphenyl borate and YM-58483 inhibited the sustained increase in cytosolic sodium, only in the presence of Orai1. These studies demonstrate that sodium permeates activated store-operated calcium entry channels, resulting in an increase in cytosolic sodium; the magnitude of this response is determined by Orai1. PMID:25428882

Sodium benzoate for treatment of hepatic encephalopathy.

PubMed

Misel, Michael L; Gish, Robert G; Patton, Heather; Mendler, Michel

2013-04-01

Hepatic encephalopathy (HE) is a serious but usually reversible neuropsychiatric complication of cirrhosis, inborn errors of metabolism involving disorders of the urea cycle, and noncirrhotic portosystemic shunting that most commonly arises from a transjugular intrahepatic portosystemic shunting procedure. Symptoms can include alterations in cognitive function, neuromuscular activity, and consciousness, as well as sleep disorders and mood changes. HE is associated with significant morbidity and mortality and, if not properly treated, will lead to increased hospital admissions and healthcare costs. Although the standard therapies of lactulose and rifaximin (Xifaxan, Salix) are effective for most patients, these drugs may be associated with significant adverse effects and expense and, in some patients, inadequate therapeutic response. A need for adjunctive therapies exists. Drugs that target serum and tissue ammonia metabolism and elimination may be important adjuncts to drugs that reduce ammonia production and absorption from the gastrointestinal tract for patients with severe or persistent overt symptoms of HE. Sodium benzoate is an inexpensive adjunctive agent that can be used in addition to lactulose and rifaximin and may provide an option for some select patients with refractory HE who have failed to respond to standard therapies or who cannot afford them. Although sodium benzoate does not share the same adverse effect profiles of standard therapies for HE, its efficacy has not been well established. Given the significant dose-dependent sodium content of this therapy, it may not be appropriate for patients with significant fluid retention or kidney dysfunction.

Sodium Benzoate for Treatment of Hepatic Encephalopathy

PubMed Central

Misel, Michael L.; Patton, Heather; Mendler, Michel

2013-01-01

Hepatic encephalopathy (HE) is a serious but usually reversible neuropsychiatric complication of cirrhosis, inborn errors of metabolism involving disorders of the urea cycle, and noncirrhotic portosystemic shunting that most commonly arises from a transjugular intrahepatic portosystemic shunting procedure. Symptoms can include alterations in cognitive function, neuromuscular activity, and consciousness, as well as sleep disorders and mood changes. HE is associated with significant morbidity and mortality and, if not properly treated, will lead to increased hospital admissions and healthcare costs. Although the standard therapies of lactulose and rifaximin (Xifaxan, Salix) are effective for most patients, these drugs may be associated with significant adverse effects and expense and, in some patients, inadequate therapeutic response. A need for adjunctive therapies exists. Drugs that target serum and tissue ammonia metabolism and elimination may be important adjuncts to drugs that reduce ammonia production and absorption from the gastrointestinal tract for patients with severe or persistent overt symptoms of HE. Sodium benzoate is an inexpensive adjunctive agent that can be used in addition to lactulose and rifaximin and may provide an option for some select patients with refractory HE who have failed to respond to standard therapies or who cannot afford them. Although sodium benzoate does not share the same adverse effect profiles of standard therapies for HE, its efficacy has not been well established. Given the significant dose-dependent sodium content of this therapy, it may not be appropriate for patients with significant fluid retention or kidney dysfunction. PMID:24711766

An evaluation of the effect of sodium bisulfate as a feed additive on Salmonella enterica serotype Enteritidis in experimentally infected broilers.

PubMed

Kassem, I I; Sanad, Y M; Stonerock, R; Rajashekara, G

2012-04-01

The colonization of broiler chickens with Salmonella can pose serious health and economic risks for both consumers and the poultry industry. Because colonization with Salmonella can lead to subsequent contamination of chicken carcasses during processing, preemptive control measures should include the reduction of this pathogen in chickens before slaughter. In this study, we evaluated the effect of sodium bisulfate, a potential antimicrobial feed additive, on Salmonella colonization of experimentally infected broiler chickens. Two hundred and forty 1-d-old chickens were infected orally with Salmonella enterica serotype Enteritidis and divided into 4 groups (each comprised of 60 chickens). Three groups received different concentrations of sodium bisulfate integrated into their feed, while the feed of the fourth group (positive control) was not treated. At time points before the broilers' slaughter age, different organs/tissues (liver, spleen, cecum, and bone marrow) and feces were aseptically collected and tested for the occurrence and density of Salmonella Enteritidis. Our results show that at 3 d postinfection, high colonization with Salmonella Enteritidis was detected and affected all tested tissues and fecal samples. Although colonization decreased across time, Salmonella Enteritidis persisted in the cecum, feces, spleen, and bone marrow, but not in the liver, until slaughter age. Furthermore, the addition of sodium bisulfate to the feed did not significantly reduce Salmonella Enteritidis numbers in infected chickens or affect the shedding of the pathogen.

Ionic channel mechanisms mediating the intrinsic excitability of Kenyon cells in the mushroom body of the cricket brain.

PubMed

Inoue, Shigeki; Murata, Kaoru; Tanaka, Aiko; Kakuta, Eri; Tanemura, Saori; Hatakeyama, Shiori; Nakamura, Atsunao; Yamamoto, Chihiro; Hasebe, Masaharu; Kosakai, Kumiko; Yoshino, Masami

2014-09-01

Intrinsic neurons within the mushroom body of the insect brain, called Kenyon cells, play an important role in olfactory associative learning. In this study, we examined the ionic mechanisms mediating the intrinsic excitability of Kenyon cells in the cricket Gryllus bimaculatus. A perforated whole-cell clamp study using β-escin indicated the existence of several inward and outward currents. Three types of inward currents (INaf, INaP, and ICa) were identified. The transient sodium current (INaf) activated at -40 mV, peaked at -26 mV, and half-inactivated at -46.7 mV. The persistent sodium current (INaP) activated at -51 mV, peaked at -23 mV, and half-inactivated at -30.7 mV. Tetrodotoxin (TTX; 1 μM) completely blocked both INaf and INaP, but 10nM TTX blocked INaf more potently than INaP. Cd(2+) (50 μM) potently blocked INaP with little effect on INaf. Riluzole (>20 μM) nonselectively blocked both INaP and INaf. The voltage-dependent calcium current (ICa) activated at -30 mV, peaked at -11.3 mV, and half-inactivated at -34 mV. The Ca(2+) channel blocker verapamil (100 μM) blocked ICa in a use-dependent manner. Cell-attached patch-clamp recordings showed the presence of a large-conductance Ca(2+)-activated K(+) (BK) channel, and the activity of this channel was decreased by removing the extracellular Ca(2+) or adding verapamil or nifedipine, and increased by adding the Ca(2+) agonist Bay K8644, indicating that Ca(2+) entry via the L-type Ca(2+) channel regulates BK channel activity. Under the current-clamp condition, membrane depolarization generated membrane oscillations in the presence of 10nM TTX or 100 μM riluzole in the bath solution. These membrane oscillations disappeared with 1 μM TTX, 50 μM Cd(2+), replacement of external Na(+) with choline, and blockage of Na(+)-activated K(+) current (IKNa) with 50 μM quinidine, indicating that membrane oscillations are primarily mediated by INaP in cooperation with IKNa. The plateau potentials observed either in Ca(2+)-free medium or in the presence of verapamil were eliminated by blocking INaP with 50 μM Cd(2+). Taken together, these results indicate that INaP and IKNa participate in the generation of membrane oscillations and that INaP additionally participates in the generation of plateau potentials and initiation of spontaneous action potentials. ICa, through L-type Ca(2+) channels, was also found to play a role in the rapid membrane repolarization of action potentials by functional coupling with BK channels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Study of corrosion behavior on the addition of sodium citrate in nickel electroplating on SPCC steel using EIS

NASA Astrophysics Data System (ADS)

Riastuti, R.; Ramadini, C.; Siallagan, S. T.; Rifki, A.; Herdino, F.

2018-04-01

The addition of sodium citrate to nickel electroplating process as additive is useful for refining the grain size of nickel deposit. The refining of grain size in nickel deposit as coating layer can improve surface performance, one of which corrosion resistance. This paper aims to investigate the effect of sodium citrate addition as grain refiner to promote corrosion resistance on SPCC steel. This experiment used Watt’s Bath solution of NiSO4 300 g/L, NiCl4 45 g/L, H3BO3 60 g/L, wetting agent 0.2 cc/L. Sodium citrate was added in composition of 45g/L and 60g/L. Nickel were deposited by direct current using current density on 6 A/dm2 at the acidity level of 5 for 30 minutes by keeping the operating temperature stable at 50°C. The grain size of nickel deposit was observed through Optical Microscope and Atomic Force Microscope (AFM). The corrosion behavior of SPCC was observed by linear polarization and Electrochemical Impedance Spectroscopy (EIS) methods using 3% NaCl solution. Based on the research, the addition of sodium citrate as grain refiner will increasing corrosion resistance on SPCC steel from 0.35 to 0.05 mm/year.

Preparation of 3D Architecture Graphdiyne Nanosheets for High-Performance Sodium-Ion Batteries and Capacitors.

PubMed

Wang, Kun; Wang, Ning; He, Jianjiang; Yang, Ze; Shen, Xiangyan; Huang, Changshui

2017-11-22

Here, we apply three-dimensional (3D) architecture graphdiyne nanosheet (GDY-NS) as anode materials for sodium-ion storage devices achieving high energy and power performance along with excellent cyclic ability. The contribution of 3D architecture nanostructure and intramolecular pores of the GDY-NS can substantially optimize the sodium storage behavior through the accommodated intramolecular pore, 3D interconnective porous structure, and increased activity sites to facilitate a fast sodium-ion-diffusion channel. The contribution of butadiyne linkages and the formation of a stable solid electrolyte interface layer are directly confirmed through the in situ Raman measurement. The GDY-NS-based sodium-ion batteries exhibit a stable reversible capacity of approximately 812 mAh g -1 at a current density of 0.05 A g -1 ; they maintain more than 405 mAh g -1 over 1000 cycles at a current density of 1 A g -1 . Furthermore, the sodium-ion capacitors could deliver a capacitance more than 200 F g -1 over 3000 cycles at 1 A g -1 and display an initial specific energy as high as 182.3 Wh kg -1 at a power density of 300 W kg -1 and maintain specific energy of 166 Wh kg -1 even at a power density of 15 000 W kg -1 . The high energy and power density along with excellent cyclic performance based on the GDY-NS anode offers a great potential toward application on next-generation energy storage devices.

Enhancing antibacterial effect of sodium hypochlorite by low electric current-assisted sonic agitation

PubMed Central

Maden, Murat; Ertuğrul, İhsan Furkan; Erik, Cevat Emre; Yetiş, Ceylan Çağıl; Tuncer, Yasin; Kahriman, Mesud

2017-01-01

Background This research focused on the effects of low electric current (μE)-assisted sonic agitation of sodium hypochlorite on Enterococcus faecalis infected human root dentin. Methods Extracted human canine roots were instrumented, sterilized, and experimentally contaminated with E. faecalis. After incubation for 21 days, the presence of the biofilm was confirmed by scanning electron microscopy (n = 3). Roots were randomly divided into seven groups according to decontamination procedures: G1: no treatment; G2: sterile saline; G3: 5.25% sodium hypochlorite; G4: passive ultrasonic irrigation; G5: EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) agitation (EA); G6: μE agitation; and G7: μE-assisted sonic agitation. Fixed μE amperage and intensities were applied in G6 and G7. Following microbial sampling, bacterial colonies were counted using the direct plating method. Results Biofilm was not eradicated in any sample. The μE-assisted sonic agitation of sodium hypochlorite revealed the lowest cfu values (p<0.05), whereas there were no significant differences among the passive ultrasonic irrigation, EndoActivator and μE agitation alone (p>0.05). Conclusions Based on available evidence, the following conclusions were drawn: The μE-assisted sonic agitation increased the antibiofilm efficiency of sodium hypochlorite than passive ultrasonic irrigation and EndoActivator. The μE-assisted sonic agitation on 5.25% sodium hypochlorite is not capable to eradicate biofilms at 10mA energy level in 60s. PMID:28854274

Enhancing antibacterial effect of sodium hypochlorite by low electric current-assisted sonic agitation.

PubMed

Maden, Murat; Ertuğrul, İhsan Furkan; Orhan, Ekim Onur; Erik, Cevat Emre; Yetiş, Ceylan Çağıl; Tuncer, Yasin; Kahriman, Mesud

2017-01-01

This research focused on the effects of low electric current (μE)-assisted sonic agitation of sodium hypochlorite on Enterococcus faecalis infected human root dentin. Extracted human canine roots were instrumented, sterilized, and experimentally contaminated with E. faecalis. After incubation for 21 days, the presence of the biofilm was confirmed by scanning electron microscopy (n = 3). Roots were randomly divided into seven groups according to decontamination procedures: G1: no treatment; G2: sterile saline; G3: 5.25% sodium hypochlorite; G4: passive ultrasonic irrigation; G5: EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) agitation (EA); G6: μE agitation; and G7: μE-assisted sonic agitation. Fixed μE amperage and intensities were applied in G6 and G7. Following microbial sampling, bacterial colonies were counted using the direct plating method. Biofilm was not eradicated in any sample. The μE-assisted sonic agitation of sodium hypochlorite revealed the lowest cfu values (p<0.05), whereas there were no significant differences among the passive ultrasonic irrigation, EndoActivator and μE agitation alone (p>0.05). Based on available evidence, the following conclusions were drawn: The μE-assisted sonic agitation increased the antibiofilm efficiency of sodium hypochlorite than passive ultrasonic irrigation and EndoActivator. The μE-assisted sonic agitation on 5.25% sodium hypochlorite is not capable to eradicate biofilms at 10mA energy level in 60s.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Natesan, K.; Momozaki, Y.; Li, M.

This report gives a description of the activities in design, fabrication, construction, and assembling of a pumped sodium loop for the sodium compatibility studies on advanced structural materials. The work is the Argonne National Laboratory (ANL) portion of the effort on the work project entitled, 'Sodium Compatibility of Advanced Fast Reactor Materials,' and is a part of Advanced Materials Development within the Reactor Campaign. The objective of this project is to develop information on sodium corrosion compatibility of advanced materials being considered for sodium reactor applications. This report gives the status of the sodium pumped loop at Argonne National Laboratory,more » the specimen details, and the technical approach to evaluate the sodium compatibility of advanced structural alloys. This report is a deliverable from ANL in FY2010 (M2GAN10SF050302) under the work package G-AN10SF0503 'Sodium Compatibility of Advanced Fast Reactor Materials.' Two reports were issued in 2009 (Natesan and Meimei Li 2009, Natesan et al. 2009) which examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design specifications for the ANL pumped loop for testing advanced structural materials. Available information was presented on solubility of several metallic and nonmetallic elements along with a discussion of the possible mechanisms for the accumulation of impurities in sodium. That report concluded that the solubility of many metals in sodium is low (<1 part per million) in the temperature range of interest in sodium reactors and such trace amounts would not impact the mechanical integrity of structural materials and components. The earlier report also analyzed the solubility and transport mechanisms of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen in laboratory sodium loops and in reactor systems such as Experimental Breeder Reactor-II, Fast Flux Test Facility, and Clinch River Breeder Reactor. Among the nonmetallic elements discussed, oxygen is deemed controllable and its concentration in sodium can be maintained in sodium for long reactor life by using cold-trap method. It was concluded that among the cold-trap and getter-trap methods, the use of cold trap is sufficient to achieve oxygen concentration of the order of 1 part per million. Under these oxygen conditions in sodium, the corrosion performance of structural materials such as austenitic stainless steels and ferritic steels will be acceptable at a maximum core outlet sodium temperature of {approx}550 C. In the current sodium compatibility studies, the oxygen concentration in sodium will be controlled and maintained at {approx}1 ppm by controlling the cold trap temperature. The oxygen concentration in sodium in the forced convection sodium loop will be controlled and monitored by maintaining the cold trap temperature in the range of 120-150 C, which would result in oxygen concentration in the range of 1-2 ppm. Uniaxial tensile specimens are being exposed to flowing sodium and will be retrieved and analyzed for corrosion and post-exposure tensile properties. Advanced materials for sodium exposure include austenitic alloy HT-UPS and ferritic-martensitic steels modified 9Cr-1Mo and NF616. Among the nonmetallic elements in sodium, carbon was assessed to have the most influence on structural materials since carbon, as an impurity, is not amenable to control and maintenance by any of the simple purification methods. The dynamic equilibrium value for carbon in sodium systems is dependent on several factors, details of which were discussed in the earlier report. The current sodium compatibility studies will examine the role of carbon concentration in sodium on the carburization-decarburization of advanced structural materials at temperatures up to 650 C. Carbon will be added to the sodium by exposure of carbon-filled iron tubes, which over time will enable carbon to diffuse through iron and dissolve into sodium. The method enables addition of dissolved carbon (without carbon particulates) in sodium that is of interest for materials compatibility evaluation. The removal of carbon from the sodium will be accomplished by exposing carbon-gettering alloys such as refractory metals that have a high partitioning coefficient for carbon and also precipitate carbides, thereby decreasing the carbon concentration in sodium.« less

Zinc naphthalenedicarboxylate coordination complex: A promising anode material for lithium and sodium-ion batteries with good cycling stability.

PubMed

Fei, Hailong; Feng, Wenjing; Xu, Tan

2017-02-15

It is important to discover new, cheap and environmental friendly electrode materials with high capacity and good cycling stability for lithium and sodium-ion batteries. Zinc 1,4-naphthalenedicarboxylate was firstly found to be stable anode materials for lithium and sodium-ion batteries. The discharge capacity can be up to 468.9mAhg -1 after 100 cycles at a current density of 100mAg -1 for lithium-ion batteries, while the second discharge capacity of 320.7mAhg -1 was achieved as anode materials for sodium-ion batteries. A possible electrochemical reaction mechanism was discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

High-Throughput Screening and Quantitative Chemical Ranking for Sodium Iodide Symporter Inhibitors in ToxCast Phase 1 Chemical Library

EPA Science Inventory

The U.S. EPA’s Endocrine Disruptor Screening Program (EDSP) and Office of Research and Development (ORD) are currently developing high throughput assays to screen chemicals that may alter the thyroid hormone pathway. One potential target in this pathway is the sodium iodide...

High-throughput screening (HTPS) of ToxCast Phase II chemical library for sodium iodide symporter (NIS) Inhibitors

EPA Science Inventory

In support of the Endocrine Disruptor Screening Program (EDSP), the U.S. EPA’s Office of Research and Development (ORD) is currently developing HTPS approaches to identify chemicals that may alter target sites in the thyroid hormone pathway. One target site is the sodium io...

USE OF GENOMIC TECHNOLOGIES AND ISOTONIC DOSE-RESPONSE MODELING IN THE DEVELOPMENT OF A BIOCHEMICAL MARKER OF EFFECT FOR PYRETHROID INSECTICIDE.

EPA Science Inventory

Pyrethroids are pesticides that disrupt nervous system function by prolongation of sodium currents

through voltage-sensitive sodium channels present in nerve membranes. Pyrethroid usage has

increased as use of other pesticides has declined. A sensitive, dose-respons...

High-Throughput Screening and Quantitative Chemical Ranking for Sodium Iodide Symporter Inhibitors in ToxCast Phase 1 Chemical Library

EPA Science Inventory

The U.S. EPA’s Endocrine Disruptor Screening Program (EDSP) and Office of Research and Development (ORD) are currently developing high throughput assays to screen chemicals that may alter the thyroid hormone pathway. One potential target in this pathway is the sodium iodide sympo...

Large-Area Carbon Nanosheets Doped with Phosphorus: A High-Performance Anode Material for Sodium-Ion Batteries.

PubMed

Hou, Hongshuai; Shao, Lidong; Zhang, Yan; Zou, Guoqiang; Chen, Jun; Ji, Xiaobo

2017-01-01

Large-area phosphorus-doped carbon nanosheets (P-CNSs) are first obtained from carbon dots (CDs) through self-assembly driving from thermal treatment with Na catalysis. This is the first time to realize the conversion from 0D CDs to 2D nanosheets doped with phosphorus. The sodium storage behavior of phosphorus-doped carbon material is also investigated for the first time. As anode material for sodium-ion batteries (SIBs), P-CNSs exhibit superb performances for electrochemical storage of sodium. When cycled at 0.1 A g -1 , the P-CNSs electrode delivers a high reversible capacity of 328 mAh g -1 , even at a high current density of 20 A g -1 , a considerable capacity of 108 mAh g -1 can still be maintained. Besides, this material also shows excellent cycling stability, at a current density of 5 A g -1 , the reversible capacity can still reach 149 mAh g -1 after 5000 cycles. This work will provide significant value for the development of both carbon materials and SIBs anode materials.

Oral Versus Topical Diclofenac Sodium in the Treatment of Osteoarthritis.

PubMed

Tieppo Francio, Vinicius; Davani, Saeid; Towery, Chris; Brown, Tony L

2017-06-01

Osteoarthritis (OA) is one of the most common causes of joint pain in the United States and non-steroidal anti-inflammatories (NSAIDs), such as Diclofenac sodium, which is currently available in two main routes of administration; oral and topical distribution have been established as one of the standard treatments for OA. Generally, oral NSAIDs are well tolerated; however our narrative review suggests that the topical solution had a better tolerability property than oral Diclofenac sodium, especially due to side effects of gastrointestinal bleeding with the utilization of the oral format. In addition, the topical route may be considered a reasonable selection by clinicians for management of musculoskeletal pain in those patients with a history of potential risk and adverse side effects. Most studies reviewed comparing oral versus topical solution of Diclofenac sodium revealed comparable efficacy, with minimal side effects utilizing the topical route. The key point of this narrative review is to help clinicians that currently must decide between very inexpensive diclofenac oral presentations and expensive topical presentations especially in the elderly population and the pros and cons of such decision-making process.

Salt balance: From space experiments to revolutionizing new clinical concepts on earth - A historical review

NASA Astrophysics Data System (ADS)

Gerzer, Rupert

2014-11-01

For a long time, sodium balance appeared to be a ;done deal; and was thought to be well understood. However, experiments in preparation of space missions showed that the concept of osmotic sodium storage and close correlations of sodium with water balance are only part of the regulatory mechanisms of body salt. By now it has turned out that the human skin is an important storage place and regulator for sodium, that sodium storage involves macrophages which in turn salt-dependently co-regulate blood pressure, that body sodium also strongly influences bone and protein metabolism, and that immune functions are also strongly influenced by sodium. In addition, the aging process appears to lead to increased body sodium storage, which in turn might influence the aging process of the human body. The current review article summarizes the developments that have led to these revolutionizing new findings and concepts as well as consequences deriving from these findings. Therefore, it is not intended in this article to give a complete literature overview over the whole field but to focus on such key literature and considerations that led to the respective developments.

Is it safe to re-access sodium bicarbonate bottles for use in minor surgery?

PubMed

Bjornson, Lindsay; Bucevska, Marija; Tilley, Peter; Verchere, Cynthia

2018-04-06

Sodium bicarbonate is added to lidocaine to reduce injection pain. In Canada, it is available in vials exceeding the injection volume 100-fold. These are single-use vials that should be disposed of after one access. Some surgeons re-use vials to reduce waste, potentially causing contamination. This study aims to review the safety of sodium bicarbonate and assess alternatives to current practice. Strains of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Burkholderia cepacia were used to assess bacterial growth in vials of sodium bicarbonate. Each pathogen was inoculated into a vial for 14 days at room temperature. At several time points, 1 mL of solution was removed and diluted. One hundred microliters were transferred to blood agar plates and incubated at 35 °C. Colony counts were calculated, averaged and plotted onto a logarithmic graph. Colony counts of all strains fell below observational threshold after 7 days in sodium bicarbonate. Although all strains were reduced, bacteria can survive in sodium bicarbonate for several days, during which transmission may occur. Sodium bicarbonate vials should be treated as single-dose, as indicated by the manufacturers. To reduce waste, hospital pharmacies can repackage sodium bicarbonate into smaller vials or pre-alkalize lidocaine with sodium bicarbonate. Copyright © 2018 Elsevier Inc. All rights reserved.

Inhibition of Neuronal Voltage-Gated Sodium Channels by Brilliant Blue G

PubMed Central

Jo, Sooyeon

2011-01-01

Brilliant blue G (BBG), best known as an antagonist of P2X7 receptors, was found to inhibit voltage-gated sodium currents in N1E-115 neuroblastoma cells. Sodium currents elicited from a holding potential of −60 mV were blocked with an IC50 of 2 μM. Block was enhanced in a use-dependent manner at higher stimulation rates. The voltage-dependence of inactivation was shifted in the hyperpolarizing direction, and recovery from inactivation was slowed by BBG. The most dramatic effect of BBG was to slow recovery from inactivation after long depolarizations, with 3 μM BBG increasing half-time for recovery (measured at −120 mV) from 24 to 854 ms after a 10-s step to 0 mV. These results were mimicked by a kinetic model in which BBG binds weakly to resting channels (Kd = 170 μM) but tightly to fast-inactivated channels (Kd = 5 μM) and even more tightly (Kd = 0.2 μM) to slow-inactivated channels. In contrast to BBG, the structurally related food-coloring dye Brilliant Blue FCF had very little effect at concentrations up to 30 μM. These results show that BBG inhibits voltage-gated sodium channels at micromolar concentrations. Although BBG inhibition of sodium channels is less potent than inhibition of P2X7 receptors, there may be significant inhibition of sodium channels at BBG concentrations achieved in spinal cord or brain during experimental treatment of spinal cord injury or Huntington's disease. Considered as a sodium channel blocker, BBG is remarkably potent, acting with more than 10-fold greater potency than lacosamide, another blocker thought to bind to slow-inactivated channels. PMID:21536754

Barbiturates Block Sodium and Potassium Conductance Increases in Voltage-Clamped Lobster Axons

PubMed Central

Blaustein, M. P.

1968-01-01

Sodium pentobarbital and sodium thiopental decrease both the peak initial (Na) and late steady-state (K) currents and reduce the maximum sodium and potassium conductance increases in voltage-clamped lobster giant axons. These barbiturates also slow the rate at which the sodium conductance turns on, and shift the normalized sodium conductance vs. voltage curves in the direction of depolarization along the voltage axis. Since pentobarbital (pKa = 8.0) blocks the action potential more effectively at pH 8.5 than at pH 6.7, the anionic form of the drug appears to be active. The data suggest that these drugs affect the axon membrane directly, rather than secondarily through effects on intermediary metabolism. It is suggested that penetration of the lipid layer of the membrane by the nonpolar portion of the barbiturate molecules may cause the decrease in membrane conductances, while electrostatic interactions involving the anionic group on the barbiturate, divalent cations, and "fixed charges" in the membrane could account for the slowing of the rate of sodium conductance turn-on and the shift of the normalized conductance curves along the voltage axis. PMID:5648829

Pet food safety: sodium in pet foods.

PubMed

Chandler, Marjorie L

2008-08-01

Healthy dogs and cats appear to be able to adjust to differing amounts of sodium in their diet via the rennin-angiotensin-aldosterone mechanisms. There is no strong evidence that increased dietary sodium increases the risk of hypertension in dogs and cats, and the current recommendation for hypertensive animals is to avoid high dietary salt intake without making a specific effort to restrict it. The prevalence of salt sensitivity and its effect on blood pressure has not been determined for cats or dogs. The ideal amount of sodium in the diet of dogs and cats with cardiac deficiency has not been determined, as increasing may detrimentally increase the extracellular fluid volume, but decreasing it may detrimentally increase the activation of the rennin-angiotensin-aldosterone system. Increased dietary sodium increases urine output and may decrease the risk of forming calcium oxalate uroliths due to the decrease in relative supersaturation of solutes. However, caution should be used in increasing the sodium intake of patients with renal disease as increased dietary sodium may have a negative effect on the kidneys independent of any effect on blood pressure.

A uniquely adaptable pore is consistent with NALCN being an ion sensor

PubMed Central

Senatore, Adriano; Spafford, J. David

2013-01-01

NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN’s most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd3+-sensitive, NMDG+-impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels. PMID:23442378

A uniquely adaptable pore is consistent with NALCN being an ion sensor.

PubMed

Senatore, Adriano; Spafford, J David

2013-01-01

NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN's most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd ( 3+) -sensitive, NMDG (+) -impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav 1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels.

[Strychnine poisoning: uncommon, but does still happen].

PubMed

van Berlo-van de Laar, Inge R F; Arbouw, Maurits E L; Bles, Carmen M A

2015-01-01

Acute strychnine poisoning is an uncommon form of intoxication, characterized by severe tonic clonic seizures and tetanus-like contractions while the patient is fully conscious. It can result in respiratory failure, leading to death. A 47-year-old man was admitted to the casualty department 2 hours after self-poisoning with strychnine. The clinical picture consisted of persistent seizures, which were treated with midazolam and propofol. The patient went into respiratory failure and asystole, so intubation and cardiac massage were initiated. Other complications were severe metabolic acidosis, hyperthermia and rhabdomyolysis with renal failure. The treatment consisted of cooling, hyperhydration and intravenous administration of sodium bicarbonate. He was discharged to a mental care institution with no persistent symptoms 11 days later. Early aggressive treatment of a strychnine intoxication can be life-saving. Knowledge of the clinical picture and the right treatment is important. Treatment is primarily focussed on stopping the convulsions and securing the airway.

Strategies to Reduce Dietary Sodium Intake

PubMed Central

Cobb, Laura K; Appel, Lawrence J; Anderson, Cheryl A.M.

2013-01-01

Opinion Excess sodium intake has an important, if not predominant, role in the pathogenesis of elevated blood pressure, one of the most important modifiable determinants of cardiovascular disease (CVD). In the United States, almost 80% of sodium in the diet comes from packaged and restaurant foods. Given the current food environment, educational efforts such as clinician counseling are useful, but a comprehensive public health approach is necessary to achieve meaningful reductions in sodium intake. A successful approach includes several key strategies, which together will both promote positive decisions by individuals and change the context in which they make those decisions. The strategies include: (1) public education, (2) individual dietary counseling, (3) food labeling, (4) coordinated, voluntary industry sodium reduction, (5) government and private sector food procurement policies, and (6) FDA regulations, as recommended by the Institute of Medicine, to modify sodium’s generally regarded as safe (GRAS) status. Population-wide reduction in sodium intake has the potential to substantially reduce the public burden of preventable CVD and reduce health care costs. PMID:22580974

Inhibition of Listeria monocytogenes growth in cured ready-to-eat meat products by use of sodium benzoate and sodium diacetate.

PubMed

Seman, D L; Quickert, S C; Borger, A C; Meyer, J D

2008-07-01

The effect of sodium benzoate (0.08 to 0.25%) in combination with different concentrations of sodium diacetate (0.05 to 0.15%) and NaClI (0.8 to 2%) and different finished product moisture (55 to 75%) on the growth of Listeria monocytogenes in ready-to-eat meat products was evaluated using a central composite design over 18 weeks of storage at 4 degrees C. The effects of these factors on time to growth were analyzed using a time-to-failure regression method. All main effects were significant except product moisture, which was significant when included in the two- and three-way interactions (P < 0.05). Sodium benzoate was more effective (lengthening time to growth) when used with increasing concentrations of sodium diacetate and salt and decreasing finished product moisture. The model indicated that low-moisture products, e.g., bologna or wieners, could have time-to-growth values longer than 18 weeks if they were formulated with 0.1% sodium benzoate and 0.1% sodium diacetate. Time to growth in high-moisture products, e.g., ham or cured turkey breast at 75% moisture, was predicted to be much shorter for the same basic formulation (0.1% sodium benzoate and 0.1% sodium diacetate). Consequently, high-moisture ready-to-eat products in which sodium benzoate is limited to 0.1% (current standard for generally recognized as safe) may need additional ingredients to effectively inhibit growth of L. monocytogenes.

Early dietary sodium restriction disrupts the peripheral anatomical development of the gustatory system.

PubMed

Krimm, R F; Hill, D L

1999-05-01

Dietary sodium restriction has profound effects on the development of peripheral taste function and central taste system anatomy. This study examined whether early dietary sodium restriction also affects innervation of taste buds. The number of geniculate ganglion cells that innervate single fungiform taste buds were quantified for the midregion of the tongue in two groups of rats: those fed either a low-sodium diet and those fed a sodium replete diet (control rats) from early prenatal development through adulthood. The same mean number of ganglion cells in developmentally sodium-restricted and control adult rats innervated taste buds on the midregion of the tongue. However, the characteristic relationship of the larger the taste bud, the more neurons that innervate it did not develop in sodium-restricted rats. The failure to form such a relationship in experimental rats was likely due to a substantially smaller mean taste bud volume than controls and probably not to changes in innervation. Further experiments demonstrated that the altered association between number of innervating neurons and taste bud size in restricted rats was reversible. Feeding developmentally sodium-restricted rats a sodium replete diet at adulthood resulted in an increase in taste bud size. Accordingly, the high correlation between taste bud volume and innervation was established in sodium-replete rats. Findings from the current study reveal that early dietary manipulations influence neuron-target interactions; however, the effects of dietary sodium restriction on peripheral gustatory anatomy can be completely restored, even in adult animals.

Carbonized-leaf Membrane with Anisotropic Surfaces for Sodium-ion Battery.

PubMed

Li, Hongbian; Shen, Fei; Luo, Wei; Dai, Jiaqi; Han, Xiaogang; Chen, Yanan; Yao, Yonggang; Zhu, Hongli; Fu, Kun; Hitz, Emily; Hu, Liangbing

2016-01-27

A simple one-step thermal pyrolysis route has been developed to prepare carbon membrane from a natural leaf. The carbonized leaf membrane possesses anisotropic surfaces and internal hierarchical porosity, exhibiting a high specific capacity of 360 mAh/g and a high initial Coulombic efficiency of 74.8% as a binder-free, current-collector-free anode for rechargeable sodium ion batteries. Moreover, large-area carbon membranes with low contact resistance are fabricated by simply stacking and carbonizing leaves, a promising strategy toward large-scale sodium-ion battery developments.

Dietary salt consumption and the knowledge, attitudes and behavior of healthy adults: a cross-sectional study from Jordan.

PubMed

Alawwa, Izzat; Dagash, Rajaa; Saleh, Akram; Ahmad, Abdelaziz

2018-12-01

High dietary sodium is recognized as a silent killer responsible for 2.3 million deaths worldwide in 2010 predominantly secondary to hypertension and its complications. Although high salt consumption is considered a worldwide public health problem, its magnitude is highly variable among different communities; therefore, it is important to study locally. This study aimed to evaluate habitual salt consumption, its important correlations, as well as the knowledge, attitude, and behavior of healthy Jordanian citizens. As potassium consumption is highly correlated and important we aimed to study both jointly. In this descriptive cross-sectional study we enrolled 103 healthy adult Jordanian citizens. All participants were interviewed for questionnaire filling, physical examination, and instructed on proper 24-hour urine collection procedure. We measured sodium and potassium concentration in the provided controlled 24-hour urine collection samples, as it is presently considered the gold standard for evaluating daily intake. The results showed an average sodium intake of 179 mmol (4.1 g) per day [higher in males at 186 mmol (4.3 g) vs. 173 mmol (4.0 g) for females], significantly above the current WHO recommendations, though only 8% regularly add salt to food. Ironically, most participants (82%) believe their salt consumption was appropriate and only 29% thought they may benefit from reducing salt intake. On the other hand, potassium intake is far below the current WHO recommendations. High sodium and low potassium intake have synergistic adverse effects on public health that is not currently addressed in Jordan. We conclude that Jordanian citizens currently consume high sodium and low potassium diet and are mostly unaware of its negative impact on their health. Hence, it is crucial for healthcare providers to intervene and adopt long-term strategies to control salt intake to reduce its negative effects in Jordan and elsewhere.

Characteristics and environmental fate of the anionic surfactant sodium lauryl ether sulphate (SLES) used as the main component in foaming agents for mechanized tunnelling.

PubMed

Barra Caracciolo, Anna; Cardoni, Martina; Pescatore, Tanita; Patrolecco, Luisa

2017-07-01

The anionic surfactant sodium lauryl ether sulphate (SLES) is the main component of most commercial products used for soil conditioning in the excavation industry, in particular as lubricants for mechanized tunnelling. Its use during the excavation processes can result in either the subsequent possible re-use of the huge amount of soil debris as by-products (e.g. land covering) or its discharge as waste. Currently, there are neither SLES soil threshold limits in European legislation, nor comprehensive studies on the environmental risk for soil ecosystems in these exposure scenarios. In this context, the present paper reviews the available data on the intrinsic characteristics of persistence and the ecotoxicological effects of the anionic surfactant SLES. Although SLES is generally reported to be biodegradable in standard tests, with degradation rates between 7 h and 30 days, depending on the initial conditions, data on its biodegradation in environmental studies are quite scarce. Consequently, assessing SLES biodegradation rates in field conditions is crucial for evaluating if in residual concentrations (typically in the range 40-500 mg/kg in excavated soils) it can or not be a potential hazard for terrestrial and water organisms. Laboratory ecotoxicological tests pointed out detrimental effects of SLES for aquatic organisms, while data on the terrestrial species are rather poor so far and further studies at the expected environmental concentrations are necessary. Finally, the review reports the main analytical methods available for detecting anionic surfactants in solid matrices and the future research needed to improve knowledge on the possible environmental risks posed by the use of SLES in foaming agents for mechanized tunnelling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prefrontal Cortex HCN1 Channels Enable Intrinsic Persistent Neural Firing and Executive Memory Function

PubMed Central

Thuault, Sébastien J.; Malleret, Gaël; Constantinople, Christine M.; Nicholls, Russell; Chen, Irene; Zhu, Judy; Panteleyev, Andrey; Vronskaya, Svetlana; Nolan, Matthew F.; Bruno, Randy

2013-01-01

In many cortical neurons, HCN1 channels are the major contributors to Ih, the hyperpolarization-activated current, which regulates the intrinsic properties of neurons and shapes their integration of synaptic inputs, paces rhythmic activity, and regulates synaptic plasticity. Here, we examine the physiological role of Ih in deep layer pyramidal neurons in mouse prefrontal cortex (PFC), focusing on persistent activity, a form of sustained firing thought to be important for the behavioral function of the PFC during working memory tasks. We find that HCN1 contributes to the intrinsic persistent firing that is induced by a brief depolarizing current stimulus in the presence of muscarinic agonists. Deletion of HCN1 or acute pharmacological blockade of Ih decreases the fraction of neurons capable of generating persistent firing. The reduction in persistent firing is caused by the membrane hyperpolarization that results from the deletion of HCN1 or Ih blockade, rather than a specific role of the hyperpolarization-activated current in generating persistent activity. In vivo recordings show that deletion of HCN1 has no effect on up states, periods of enhanced synaptic network activity. Parallel behavioral studies demonstrate that HCN1 contributes to the PFC-dependent resolution of proactive interference during working memory. These results thus provide genetic evidence demonstrating the importance of HCN1 to intrinsic persistent firing and the behavioral output of the PFC. The causal role of intrinsic persistent firing in PFC-mediated behavior remains an open question. PMID:23966682

Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.

PubMed

Elmore, Amy R

2005-01-01

Potassium Silicate, Sodium Metasilicate, and Sodium Silicate combine metal cations with silica to form inorganic salts used as corrosion inhibitors in cosmetics. Sodium Metasilicate also functions as a chelating agent and Sodium Silicate as a buffering and pH adjuster. Sodium Metasilicate is currently used in 168 formulations at concentrations ranging from 13% to 18%. Sodium Silicate is currently used in 24 formulations at concentrations ranging from 0.3% to 55%. Potassium Silicate and Sodium Silicate have been reported as being used in industrial cleaners and detergents. Sodium Metasilicate is a GRAS (generally regarded as safe) food ingredient. Aqueous solutions of Sodium Silicate species are a part of a chemical continuum of silicates based on an equilibrium of alkali, water, and silica. pH determines the solubility of silica and, together with concentration, determines the degree of polymerization. Sodium Silicate administered orally is readily absorbed from the alimentary canal and excreted in the urine. The toxicity of these silicates has been related to the molar ratio of SiO2/Na2O and the concentration being used. The Sodium Metasilicate acute oral LD50 ranged from 847 mg/kg in male rats to 1349.3 mg/kg in female rats and from 770 mg/kg in female mice to 820 mg/kg in male mice. Gross lesions of variable severity were found in the oral cavity, pharynx, esophagus, stomach, larynx, lungs, and kidneys of dogs receiving 0.25 g/kg or more of a commercial detergent containing Sodium Metasilicate; similar lesions were also seen in pigs administered the same detergent and dose. Male rats orally administered 464 mg/kg of a 20% solution containing either 2.0 or 2.4 to 1.0 ratio of sodium oxide showed no signs of toxicity, whereas doses of 1000 and 2150 mg/kg produced gasping, dypsnea, and acute depression. Dogs fed 2.4 g/kg/day of Sodium Silicate for 4 weeks had gross renal lesions but no impairment of renal function. Dermal irritation of Potassium Silicate, Sodium Metasilicate, and Sodium Silicate ranged from negligible to severe, depending on the species tested and the molar ratio and concentration tested. Sodium Metasilicate was negative in the local lymph node assay (LLNA), but a delayed-type hypersensitivity response was observed in mice. Potassium Silicate was nonirritating in two acute eye irritation studies in rabbits. Sodium Metasilicate (42.4% H2O) was corrosive to the rabbit eye. Sodium Silicate was a severe eye irritant in some eye irritation studies, but was irritating or nonirritating in others. A skin freshener containing Sodium Silicate was nonirritating. Sodium Metasilicate was nonmutagenic in bacterial cells. Rats given Sodium Silicate (600 and 1200 ppm of added silica) in the drinking water in reproductive studies produced a reduced number of offspring: to 67% of controls at 600 ppm and to 80% of controls at 1200 ppm. Three adult rats injected intratesticularly and subcutaneously with 0.8 mM/kg of Sodium Silicate showed no morphological changes in the testes and no effect on the residual spermatozoa in the ductus deferens. Sodium Metasilicate (37% in a detergent) mixed with water was a severe skin irritant when tested on intact and abraded human skin, but 6%, 7%, and 13% Sodium Silicate were negligible skin irritants to intact and abraded human skin. Sodium Silicate (10% of a 40% aqueous solution) was negative in a repeat-insult predictive patch test in humans. The same aqueous solution of Sodium Silicate was considered a mild irritant under normal use conditions in a study of cumulative irritant properties. The Cosmetic Ingredient Review (CIR) Expert Panel recognized the irritation potential of these ingredients, especially in leave-on products. However, because these ingredients have limited dermal absorption and Sodium Metasilicate is a GRAS direct food substance, the Panel deemed the ingredients safe for use in cosmetic products in the practices of use and concentration described in this safety assessment, when formulated to avoid irritation.

Sodium Intake among US School-Aged Children: National Health and Nutrition Examination Survey, 2011–2012

PubMed Central

Quader, Zerleen S.; Gillespie, Cathleen; Sliwa, Sarah A.; Ahuja, Jaspreet K. C.; Burdg, Jinee P.; Moshfegh, Alanna; Pehrsson, Pamela R.; Gunn, Janelle P.; Mugavero, Kristy; Cogswell, Mary E.

2017-01-01

Background Identifying current major dietary sources of sodium can enhance strategies to reduce excess sodium intake, which occurs among 90% of US school-aged children. Objective To describe major food sources, places obtained, and eating occasions contributing to sodium intake among US school-aged children. Design Cross-sectional analysis of data from the 2011–2012 National Health and Nutrition Examination Survey. Participants/setting A nationally representative sample of 2,142 US children aged 6 to 18 years who completed a 24-hour dietary recall. Main outcome measures Population proportions of sodium intake from major food categories, places, and eating occasions. Statistical analyses performed Statistical analyses accounted for the complex survey design and sampling. Wald F tests and t tests were used to examine differences between subgroups. Results Average daily sodium intake was highest among adolescents aged 14 to 18 years (3,565±120 mg), lowest among girls (2,919±74 mg). Little variation was seen in average intakes or the top five sodium contributors by sociodemographic characteristics or weight status. Ten food categories contributed to almost half (48%) of US school-aged children’s sodium intake, and included pizza, Mexican-mixed dishes, sandwiches, breads, cold cuts, soups, savory snacks, cheese, plain milk, and poultry. More than 80 food categories contributed to the other half of children’s sodium intake. Foods obtained from stores contributed 58% of sodium intake, fast-food/pizza restaurants contributed 16%, and school cafeterias contributed 10%. Thirty-nine percent of sodium intake was consumed at dinner, 31% at lunch, 16% from snacks, and 14% at breakfast. Conclusions With the exception of plain milk, which naturally contains sodium, the top 10 food categories contributing to US schoolchildren’s sodium intake during 2011–2012 comprised foods in which sodium is added during processing or preparation. Sodium is consumed throughout the day from multiple foods and locations, highlighting the importance of sodium reduction across the US food supply. PMID:27818138

The Sunk Cost Effect with Pigeons: Some Determinants of Decisions about Persistence

ERIC Educational Resources Information Center

Macaskill, Anne C.; Hackenberg, Timothy D.

2012-01-01

The sunk cost effect occurs when an individual persists following an initial investment, even when persisting is costly in the long run. The current study used a laboratory model of the sunk cost effect. Two response alternatives were available: Pigeons could persist by responding on a schedule key with mixed ratio requirements, or escape by…

Evaluation of sodium chlorate as a pre-harvest intervention for controlling Salmonella in the peripheral lymph nodes of cattle

USDA-ARS?s Scientific Manuscript database

The objective of the current study was to evaluate sodium chlorate as a potential pre-harvest intervention for reducing or eliminating Salmonella from the peripheral lymph nodes of experimentally-infected cattle. The peripheral lymph nodes of Holstein steers (approx. BW = 160 kg; 4 and 6 head in co...

Properties of the calcium-activated chloride current in heart.

PubMed

Zygmunt, A C; Gibbons, W R

1992-03-01

We used the whole cell patch clamp technique to study transient outward currents of single rabbit atrial cells. A large transient current, IA, was blocked by 4-aminopyridine (4AP) and/or by depolarized holding potentials. After block of IA, a smaller transient current remained. It was completely blocked by nisoldipine, cadmium, ryanodine, or caffeine, which indicates that all of the 4AP-resistant current is activated by the calcium transient that causes contraction. Neither calcium-activated potassium current nor calcium-activated nonspecific cation current appeared to contribute to the 4AP-resistant transient current. The transient current disappeared when ECl was made equal to the pulse potential; it was present in potassium-free internal and external solutions. It was blocked by the anion transport blockers SITS and DIDS, and the reversal potential of instantaneous current-voltage relations varied with extracellular chloride as predicted for a chloride-selective conductance. We concluded that the 4AP-resistant transient outward current of atrial cells is produced by a calcium-activated chloride current like the current ICl(Ca) of ventricular cells (1991. Circulation Research. 68:424-437). ICl(Ca) in atrial cells demonstrated outward rectification, even when intracellular chloride concentration was higher than extracellular. When ICa was inactivated or allowed to recover from inactivation, amplitudes of ICl(Ca) and ICa were closely correlated. The results were consistent with the view that ICl(Ca) does not undergo independent inactivation. Tentatively, we propose that ICl(Ca) is transient because it is activated by an intracellular calcium transient. Lowering extracellular sodium increased the peak outward transient current. The current was insensitive to the choice of sodium substitute. Because a recently identified time-independent, adrenergically activated chloride current in heart is reduced in low sodium, these data suggest that the two chloride currents are produced by different populations of channels.

Sodium and potassium in the lunar atmosphere

NASA Technical Reports Server (NTRS)

Potter, A. E.; Morgan, T. H.

1991-01-01

The discovery that sodium and potassium vapor can be observed in the lunar atmosphere using ground-based telescopes has opened up a field of investigation that was closed after the last Apollo mission to the Moon. Sodium has been detected at altitudes up to 1500 km above the surface. This implies a high effective temperature for sodium, of the order of 1000 K. However, there is some evidence for two populations of sodium and potassium, one at temperatures corresponding to the surface, and another corresponding to high temperatures. The sources for the lunar atmosphere are not understood. Meteoric bombardment of the surface, solar wind sputtering of the surface, and photo-sputtering of the surface have all been suggested as possible sources for the lunar atmosphere. One of the objectives of the current research is to test different hypotheses by measurements of the atmosphere under different conditions of solar illumination and shielding from the solar wind by the Earth.

Sodium-based hydrides for thermal energy applications

NASA Astrophysics Data System (ADS)

Sheppard, D. A.; Humphries, T. D.; Buckley, C. E.

2016-04-01

Concentrating solar-thermal power (CSP) with thermal energy storage (TES) represents an attractive alternative to conventional fossil fuels for base-load power generation. Sodium alanate (NaAlH4) is a well-known sodium-based complex metal hydride but, more recently, high-temperature sodium-based complex metal hydrides have been considered for TES. This review considers the current state of the art for NaH, NaMgH3- x F x , Na-based transition metal hydrides, NaBH4 and Na3AlH6 for TES and heat pumping applications. These metal hydrides have a number of advantages over other classes of heat storage materials such as high thermal energy storage capacity, low volume, relatively low cost and a wide range of operating temperatures (100 °C to more than 650 °C). Potential safety issues associated with the use of high-temperature sodium-based hydrides are also addressed.

[Effect of imidapril on the effective refractory period and sodium current of ventricular noninfarction zone in healed myocardial infarction].

PubMed

Li, Yang; Niu, Hui-Yan; Liu, Nian; Zhang, Cun-Tai; Lu, Zai-Ying; Wang, Shi-Wen

2005-07-01

To investigate the effects of imidapril (IMI) on effective refractory period (ERP) and sodium current (I(Na)) of myocytes in ventricular noninfarction zone of healed myocardial infarction (HMI) in rabbit models. Rabbits with left coronary artery ligation were prepared and IMI (0.625 mg x kg(-1) x d(-1), 8 weeks) was orally administered. The ERP and sodium current were recorded. The ERP in HMI heart was prolonged. The ERP in IMI group was lower significantly than that of HMI group. The I(Na) density of myocyte in HMI ventricle decreased obviously. V 1/2 of steady state inactivation of I(Na) shifted to hyperpolarization, and time constant (tau) of recovery from inactivation in HMI ventricular myocyte was longer than that of sham ventricular myocyte. I(Na) density in IMI group increased markedly as compared with that of HMI group. IMI was shown to reverse the abnormal prolongation of ERP in rabbit heart with the HMI and increase I(Na) density. It may be the mechanism of IMI preventing against antiarrhythmia in healed myocardical infarction.

Novice Teachers' Knowledge of Reading-Related Disabilities and Dyslexia

ERIC Educational Resources Information Center

Washburn, Erin K.; Mulcahy, Candance A.; Musante, Gail; Joshi, R. Malatesha

2017-01-01

Current understandings about the nature of persistent reading problems have been influenced by researchers in numerous fields. Researchers have noted that a current and accurate understanding of reading disabilities, such as dyslexia, can be helpful in assessing, teaching and supporting individuals with persistent reading problems. The purpose of…

Functional expression and purification of recombinant Tx1, a sodium channel blocker neurotoxin from the venom of the Brazilian "armed" spider, Phoneutria nigriventer.

PubMed

Diniz, Marcelo R V; Theakston, R David G; Crampton, Julian M; Nascimento Cordeiro, Marta do; Pimenta, Adriano M C; De Lima, Maria Elena; Diniz, Carlos R

2006-11-01

Tx1 from the venom of the Brazilian spider, Phoneutria nigriventer, is a lethal neurotoxic polypeptide of M(r) 8600 Da with 14 cysteine residues. It is a novel sodium channel blocker which reversibly inhibits sodium currents in CHO cells expressing recombinant sodium (Nav1.2) channels. We cloned and expressed the Tx1 toxin as a thioredoxin fusion product in the cytoplasm of Escherichia coli. After semipurification by immobilized Ni-ion affinity chromatography, the recombinant Tx1 was purified by reverse phase chromatography and characterized. It displayed similar biochemical and pharmacological properties to the native toxin, and it should be useful for further investigation of structure-function relationship of Na channels.

Polyamine FTX-3.3 and polyamine amide sFTX-3.3 inhibit presynaptic calcium currents and acetylcholine release at mouse motor nerve terminals.

PubMed

Fatehi, M; Rowan, E G; Harvey, A L; Moya, E; Blagbrough, I S

1997-02-01

FTX-3.3 is the proposed structure of a calcium-channel blocking toxin that has been isolated from the funnel web spider (Agelenopsis aperta). The effects of FTX-3.3 and one of its analogues, sFTX-3.3, on acetylcholine release, on presynaptic currents at mouse motor nerve terminals and on whole-cell sodium currents in SK.N.SH cells (a human neuroblastoma cell line) have been studied. FTX-3.3 (10-30 microM) and sFTX-3.3 (100-300 microM) reversibly reduced release of acetylcholine by approximately 70-90% and 40-60%, respectively. FTX-3.3 (10 microM) blocked the fast component of presynaptic calcium currents by approximately 60%. sFTX-3.3 (100 microM) reduced the duration of the slow component of presynaptic calcium currents by about 50% of the control and also reduced presynaptic sodium current by approximately 20% of the control. sFTX-3.3 (100 microM) reduced whole-cell sodium current recorded from SK.N.SH cells by approximately 15%, whereas FTX-3.3, even at 200 microM, did not affect this current. Since the only difference in chemical structures of these toxins is that sFTX-3.3 has an amide function which is absent in FTX-3.3, the amide function may be responsible for the reduced potency and selectivity of sFTX-3.3. This study also provides further support for the existence of P-type calcium channels at mouse motor nerve terminals.

Genistein inhibits voltage-gated sodium currents in SCG neurons through protein tyrosine kinase-dependent and kinase-independent mechanisms.

PubMed

Jia, Zhanfeng; Jia, Yueqin; Liu, Boyi; Zhao, Zhiying; Jia, Qingzhong; Liang, Huiling; Zhang, Hailin

2008-08-01

Voltage-gated sodium channels play a crucial role in the initiation and propagation of neuronal action potentials. Genistein, an isoflavone phytoestrogen, has long been used as a broad-spectrum inhibitor of protein tyrosine kinases (PTK). In addition, genistein-induced modulation of ion channels has been described previously in the literature. In this study, we investigated the effect of genistein on voltage-gated sodium channels in rat superior cervical ganglia (SCG) neurons. The results show that genistein inhibits Na(+) currents in a concentration-dependent manner, with a concentration of half-maximal effect (IC(50)) at 9.1 +/- 0.9 microM. Genistein positively shifted the voltage dependence of activation but did not affect inactivation of the Na(+) current. The inactive genistein analog daidzein also inhibited Na(+) currents, but was less effective than genistein. The IC(50) for daidzein-induced inhibition was 20.7 +/- 0.1 microM. Vanadate, an inhibitor of protein tyrosine phosphatases, partially but significantly reversed genistein-induced inhibition of Na(+) currents. Other protein tyrosine kinase antagonists such as tyrphostin 23, an erbstatin analog, and PP2 all had small but significant inhibitory effects on Na(+) currents. Among all active and inactive tyrosine kinase inhibitors tested, genistein was the most potent inhibitor of Na(+) currents. These results suggest that genistein inhibits Na(+) currents in rat SCG neurons through two distinct mechanisms: protein tyrosine kinase-independent, and protein tyrosine kinase-dependent mechanisms. Furthermore, the Src kinase family may be involved in the basal phosphorylation of the Na(+) channel.

Loss of absorptive capacity for sodium and chloride in the colon causes diarrhoea in Potomac horse fever.

PubMed

Rikihisa, Y; Johnson, G C; Wang, Y Z; Reed, S M; Fertel, R; Cooke, H J

1992-05-01

Ehrlichia risticii, an obligate intracellular bacterium in the family Rickettsiaceae, causes Potomac horse fever which is often associated with severe watery diarrhoea. The mechanism of the diarrhoea is unknown. The aim of this study was to determine whether sodium and chloride transport, morphology and cyclic adenosine 3', 5'-monophosphate (cyclic AMP) content of colonic mucosa was altered in E risticii-infected horses. Mucosa-submucosa sheets from the large and small colon of nine infected and seven to nine uninfected horses were set up in Ussing chambers for measurement of short-circuit current and transepithelial 22Na and 36Cl fluxes. Uninfected tissues absorbed both sodium and chloride whereas absorption of sodium and chloride was abolished in infected tissues. Bethanechol and histamine evoked a concentration-dependent increase in short-circuit current in both groups, but the responses were attenuated at all concentrations in infected horses. Slight focal degeneration of colonic epithelial cells and loss of microvilli from glandular epithelial cells occurred in infected horses. There was a significant increase in cyclic AMP content in colonic mucosa of infected animals. The results suggest that E risticii infection induces focal microscopic degeneration of epithelial cells and an increase in intracellular cyclic AMP in colonic mucosa. These alterations are associated with malabsorption of sodium and chloride and could cause diarrhoea.

Sodium pump molecular activity and membrane lipid composition in two disparate ectotherms, and comparison with endotherms.

PubMed

Turner, Nigel; Hulbert, A J; Else, Paul L

2005-02-01

Previous research has shown that the lower sodium pump molecular activity observed in tissues of ectotherms compared to endotherms, is largely related to the lower levels of polyunsaturates and higher levels of monounsaturates found in the cell membranes of ectotherms. Marine-based ectotherms, however, have very polyunsaturated membranes, and in the current study, we measured molecular activity and membrane lipid composition in tissues of two disparate ectothermic species, the octopus (Octopus vulgaris) and the bearded dragon lizard (Pogona vitticeps), to determine whether the high level of membrane polyunsaturation generally observed in marine-based ectotherms is associated with an increased sodium pump molecular activity relative to other ectotherms. Phospholipids from all tissues of the octopus were highly polyunsaturated and contained high concentrations of the omega-3 polyunsaturate, docosahexaenoic acid (22:6 (n-3)). In contrast, phospholipids from bearded dragon tissues contained higher proportions of monounsaturates and lower proportions of polyunsaturates. Sodium pump molecular activity was only moderately elevated in tissues of the octopus compared to the bearded dragon, despite the much greater level of polyunsaturation in octopus membranes. When the current data were combined with data for the ectothermic cane toad, a significant (P = 0.003) correlation was observed between sodium pump molecular activity and the content of 22:6 (n-3) in the surrounding membrane. These results are discussed in relation to recent work which shows a similar relationship in endotherms.

The Concept about the Regeneration of Spent Borohydrides and Used Catalysts from Green Electricity

PubMed Central

Liu, Cheng-Hong; Chen, Bing-Hung

2015-01-01

Currently, the Brown-Schlesinger process is still regarded as the most common and mature method for the commercial production of sodium borohydride (NaBH4). However, the metallic sodium, currently produced from the electrolysis of molten NaCl that is mass-produced by evaporation of seawater or brine, is probably the most costly raw material. Recently, several reports have demonstrated the feasibility of utilizing green electricity such as offshore wind power to produce metallic sodium through electrolysis of seawater. Based on this concept, we have made improvements and modified our previously proposed life cycle of sodium borohydride (NaBH4) and ammonia borane (NH3BH3), in order to further reduce costs in the conventional Brown-Schlesinger process. In summary, the revision in the concept combining the regeneration of the spent borohydrides and the used catalysts with the green electricity is reflected in (1) that metallic sodium could be produced from NaCl of high purity obtained from the conversion of the byproduct in the synthesis of NH3BH3 to devoid the complicated purification procedures if produced from seawater; and (2) that the recycling and the regeneration processes of the spent NaBH4 and NH3BH3 as well as the used catalysts could be simultaneously carried out and combined with the proposed life cycle of borohydrides.

Molecular properties of the SLC13 family of dicarboxylate and sulfate transporters

PubMed Central

Pajor, Ana M.

2006-01-01

The SLC13 gene family consists of five members in humans, with corresponding orthologs from different vertebrate species. All five genes code for sodium-coupled transporters that are found on the plasma membrane. Two of the transporters, NaS1 and NaS2, carry substrates such as sulfate, selenate and thiosulfate. The other members of the family (NaDC1, NaDC3, and NaCT) are transporters for di- and tri-carboxylates including succinate, citrate and α-ketoglutarate. The SLC13 transporters from vertebrates are electrogenic and they produce inward currents in the presence of sodium and substrate. Substrate-independent leak currents have also been described. Structure–function studies have identified the carboxy terminal half of these proteins as the most important for determining function. Transmembrane helices 9 and 10 may form part of the substrate permeation pathway and participate in conformational changes during the transport cycle. This review also discusses new members of the SLC13 superfamily that exhibit both sodium-dependent and sodium-independent transport mechanisms. The Indy protein from Drosophila, involved in determining lifespan, and the plant vacuolar malate transporter are both sodium-independent dicarboxylate transporters, possibly acting as exchangers. The purpose of this review is to provide an update on new advances in this gene family, particularly on structure–function studies and new members of the family. PMID:16211368

Cytotoxicity, Bactericidal, and Antioxidant Activity of Sodium Alginate Hydrosols Treated with Direct Electric Current

PubMed Central

Król, Żaneta; Marycz, Krzysztof; Kulig, Dominika; Marędziak, Monika; Jarmoluk, Andrzej

2017-01-01

The aim of the study was to investigate the effect of using direct electric current (DC) of 0, 200, and 400 mA for five minutes on the physiochemical properties, cytotoxicity, antibacterial, and antioxidant activity of sodium alginate hydrosols with different sodium chloride concentrations. The pH, oxidation-reduction potential (ORP), electrical conductivity (EC), and available chlorine concentration (ACC) were measured. The effect of sodium alginate hydrosols treated with DC on Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Micrococcus luteus, Escherichia coli, Salmonella enteritidis, Yersinia enterocolitica, Pseudomonas fluorescence, and RAW 264.7 and L929 cells was investigated. Subsequently, the antioxidant properties of hydrosols were evaluated by determining the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) and ferric reducing antioxidant power (FRAP). The results have shown that after applying 400 mA in hydrosol samples with 0.1% and 0.2% NaCl all tested bacteria were inactivated. The ACC concentration of C400 samples with NaCl was equal to 13.95 and 19.71 mg/L, respectively. The cytotoxicity analysis revealed that optimized electric field conditions and the addition of sodium chloride allow for the avoidance of toxicity effects on normal cells without disturbing the antibacterial effects. Due to the presence of oxidizing substances, the DPPH of variants treated with DC was lower than the DPPH of control samples. PMID:28327520

Cytotoxicity, Bactericidal, and Antioxidant Activity of Sodium Alginate Hydrosols Treated with Direct Electric Current.

PubMed

Król, Żaneta; Marycz, Krzysztof; Kulig, Dominika; Marędziak, Monika; Jarmoluk, Andrzej

2017-03-22

The aim of the study was to investigate the effect of using direct electric current (DC) of 0, 200, and 400 mA for five minutes on the physiochemical properties, cytotoxicity, antibacterial, and antioxidant activity of sodium alginate hydrosols with different sodium chloride concentrations. The pH, oxidation-reduction potential (ORP), electrical conductivity (EC), and available chlorine concentration (ACC) were measured. The effect of sodium alginate hydrosols treated with DC on Staphylococcus aureus , Listeria monocytogenes , Bacillus cereus , Micrococcus luteus , Escherichia coli , Salmonella enteritidis , Yersinia enterocolitica , Pseudomonas fluorescence , and RAW 264.7 and L929 cells was investigated. Subsequently, the antioxidant properties of hydrosols were evaluated by determining the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) and ferric reducing antioxidant power (FRAP). The results have shown that after applying 400 mA in hydrosol samples with 0.1% and 0.2% NaCl all tested bacteria were inactivated. The ACC concentration of C400 samples with NaCl was equal to 13.95 and 19.71 mg/L, respectively. The cytotoxicity analysis revealed that optimized electric field conditions and the addition of sodium chloride allow for the avoidance of toxicity effects on normal cells without disturbing the antibacterial effects. Due to the presence of oxidizing substances, the DPPH of variants treated with DC was lower than the DPPH of control samples.

SCN5A (NaV1.5) Variant Functional Perturbation and Clinical Presentation: Variants of a Certain Significance.

PubMed

Kroncke, Brett M; Glazer, Andrew M; Smith, Derek K; Blume, Jeffrey D; Roden, Dan M

2018-05-01

Accurately predicting the impact of rare nonsynonymous variants on disease risk is an important goal in precision medicine. Variants in the cardiac sodium channel SCN5A (protein Na V 1.5; voltage-dependent cardiac Na+ channel) are associated with multiple arrhythmia disorders, including Brugada syndrome and long QT syndrome. Rare SCN5A variants also occur in ≈1% of unaffected individuals. We hypothesized that in vitro electrophysiological functional parameters explain a statistically significant portion of the variability in disease penetrance. From a comprehensive literature review, we quantified the number of carriers presenting with and without disease for 1712 reported SCN5A variants. For 356 variants, data were also available for 5 Na V 1.5 electrophysiological parameters: peak current, late/persistent current, steady-state V1/2 of activation and inactivation, and recovery from inactivation. We found that peak and late current significantly associate with Brugada syndrome ( P <0.001; ρ=-0.44; Spearman rank test) and long QT syndrome disease penetrance ( P <0.001; ρ=0.37). Steady-state V1/2 activation and recovery from inactivation associate significantly with Brugada syndrome and long QT syndrome penetrance, respectively. Continuous estimates of disease penetrance align with the current American College of Medical Genetics classification paradigm. Na V 1.5 in vitro electrophysiological parameters are correlated with Brugada syndrome and long QT syndrome disease risk. Our data emphasize the value of in vitro electrophysiological characterization and incorporating counts of affected and unaffected carriers to aid variant classification. This quantitative analysis of the electrophysiological literature should aid the interpretation of Na V 1.5 variant electrophysiological abnormalities and help improve Na V 1.5 variant classification. © 2018 American Heart Association, Inc.

Gateways to Clinical Trials.

PubMed

Bayés, M; Rabasseda, X; Prous, J R

2002-09-01

Gateways to Clinical Trials is a guide to the most recent clinical trials in current literature and congresses. The data in the following tables has been retrieved from the Clinical Studies knowledge area of Prous Science Integrity, the drug discovery and development portal, http://integrity.prous.com. This issue focuses on the following selection of drugs: Adalimumab, aeroDose insulin inhaler, agomelatine, alendronic acid sodium salt, aliskiren fumarate, alteplase, amlodipine, aspirin, atazanavir; Bacillus Calmette-Guérin, basiliximab, BQ-788, bupropion hydrochloride; Cabergoline, caffeine citrate, carbamazepine, carvedilol, celecoxib, cyclosporine, clopidogrel hydrogensulfate, colestyramine; Dexamethasone, diclofenac sodium, digoxin, dipyridamole, docetaxel, dutasteride; Eletriptan, enfuvirtidie, eplerenone, ergotamine tartrate, esomeprazole magnesium, estramustine phosphate sodium; Finasteride, fluticasone propionate, fosinopril sodium; Ganciclovir, GBE-761-ONC, glatiramer acetate, gliclazide, granulocyte-CSF; Heparin sodium, human isophane insulin (pyr), Hydrochlorothiazide; Ibuprofen, inhaled insulin, interferon alfa, interferon beta-1a; Laminvudine, lansoprazole, lisinopril, lonafarnib, losartan potassium, lumiracoxib; MAb G250, meloxicam methotrexate, methylprednisolone aceponate, mitomycin, mycophenolate mofetil; Naproxen sodium, natalizumab, nelfinavir mesilate, nemifitide ditriflutate, nimesulide; Omalizumab, omapatrilat, omeprazole, oxybutynin chloride; Pantoprazole sodium, paracetamol, paroxetine, pentoxifylline, pergolide mesylate, permixon, phVEGF-A165, pramipexole hydrochloride, prasterone, prednisone, probucol, propiverine hydrochloride; Rabeprazole sodium, resiniferatoxin, risedronate sodium, risperidone, rofecoxib rosiglitazone maleate, ruboxistaurin mesilate hydrate; Selegiline transdermal system, sertraline, sildenafil citrate, streptokinase; Tadalafil, tamsulosin hydrochloride, technosphere/Insulin, tegaserod maleate, tenofovir disoproxil fumarate, testosterone heptanoate, testosterone undecanoate, tipifarnib, tolterodine tartrate, topiramate, troglitazone; Ursodeoxycholic acid; Valdecoxib, valsartan, vardenafil, venlafaxine hydrochloride, VX-745.

Na+/Ca2+ exchange in cardiac myocytes. Effect of ouabain on voltage dependence.

PubMed

Lee, H C; Clusin, W T

1987-02-01

Sarcolemmal sodium/calcium exchange activity was examined in individual chick embryonic myocardial cell aggregates that were loaded with quin 2. The baseline [Ca2+]i was 68 +/- 4 nM (n = 29). Abrupt superfusion with sodium-free lithium solution produced a fourfold increase in steady-state [Ca2+]i to 290 +/- 19 nM, which was reversible upon sodium restitution. Other methods of increasing [Ca2+]i such as KCl-depolarization or caffeine produced a dose-dependent increase in quin 2 fluorescence, accompanied by sustained contracture. The [Ca2+]i increase in zero sodium was linear, and its half-time (t1/2) of 15.1 +/- 0.1 s was similar to that of the sodium-free contracture (t1/2 = 14.4 +/- 0.5 s) under the same conditions. The sodium-dependent [Ca2+]i increase was not significantly greater when potassium served as the sodium substitute instead of lithium. This suggests that sodium/calcium exchange has little voltage dependence in this situation. However, in aggregates pretreated with ouabain (2.5 microM), the [Ca2+]i increase was almost threefold greater with potassium than with lithium (P less than 0.007). Ouabain therefore potentiated the effect of membrane potential on calcium influx. We propose that elevation of [Na2+]i is a prerequisite for voltage dependence of the sodium/calcium exchange under the conditions studied. Sodium loading will then drastically increase calcium influx during the action potential while inducing an outward membrane current that could accelerate repolarization.

Sodium sulfur battery flight experiment definition study

NASA Technical Reports Server (NTRS)

Chang, Rebecca R.; Minck, Robert

1989-01-01

Sodium-sulfur batteries were identified as the most likely successor to nickel-hydrogen batteries for space applications. One advantage of the Na/S battery system is that the usable specific energy is two to three times that of nickel-hydrogen batteries. This represents a significant launch cost savings or increased payload mass capabilities. Sodium-sulfur batteries support NASA OAST's proposed Civil Space Technology Initiative goal of a factor of two improvement in spacecraft power system performance, as well as the proposed Spacecraft 2000 initiative. The sodium-sulfur battery operates at between 300 and 400 C, using liquid sodium and sulfur/polysulfide electrodes and solid ceramic electrolyte. The transport of the electrode materials to the surface of the electrolyte is through wicking/capillary forces. These critical transport functions must be demonstrated under actual microgravity conditions before sodium-sulfur batteries can be confidently utilized in space. Ford Aerospace Corporation, under contract to NASA Lewis Research Center, is currently working on the sodium-sulfur battery space flight experiment definition study. The objective is to design the experiment that will demonstrate operation of the sodium-sulfur battery/cell in the space environment with particular emphasis on evaluation of microgravity effects. Experimental payload definitions were completed and preliminary designs of the experiment were defined.

Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore

PubMed Central

Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

2016-01-01

Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process. PMID:27374991

Usual sodium intakes compared with current dietary guidelines --- United States, 2005-2008.

PubMed

2011-10-21

High sodium intake can increase blood pressure and the risk for heart disease and stroke. According to the Dietary Guidelines for Americans, 2010, persons in the United States aged ≥2 years should limit daily sodium intake to <2,300 mg. Subpopulations that would benefit from further reducing sodium intake to 1,500 mg daily include 1) persons aged ≥51 years, 2) blacks, and 3) persons with hypertension, diabetes, or chronic kidney disease. To estimate the proportion of the U.S. population for whom the 1,500 mg recommendation applies and to assess the usual sodium intake for those persons, CDC and the National Institutes of Health used data for 2005-2008 from the National Health and Nutrition Examination Survey (NHANES). This report summarizes the results of that assessment, which determined that, although 47.6% of persons aged ≥2 years meet the criteria to limit their daily sodium intake to 1,500 mg, the usual daily sodium intake for 98.6% of those persons was >1,500 mg. Moreover, for 88.2% of the remaining U.S. population, daily sodium intake was greater than the recommended <2,300 mg. New population-based strategies and increased public health and private efforts will be needed to meet the Dietary Guidelines recommendations.

Mechanism of sodium chloride in promoting reduction of high-magnesium low-nickel oxide ore.

PubMed

Zhou, Shiwei; Wei, Yonggang; Li, Bo; Wang, Hua; Ma, Baozhong; Wang, Chengyan

2016-07-04

Sodium chloride has been proved that it is an effective promoter for the reduction of high-magnesium, low-nickel oxide ore. The aim of current work is to clarify the promotion behavior of sodium chloride in the roasting reduction process. The influence of moisture on the reduction of ore in the presence of sodium chloride is studied to get clear comprehension of promotion process. In the presence of moisture, the HCl is produced by pyrohydrolysis of sodium chloride for chlorinating nickel and iron oxides, moreover, interactions between metallic oxides and sodium chloride are also a way for chlorination at high temperature (>802 °C); subsequently, the metal chloride would be reduced by reductant. In the absence of moisture, the magnetic separation results show that the recoveries of iron and nickel have a significant increase; moreover, olivine structure would be destroyed gradually with the increase of roasting temperature in the action of sodium chloride, and the sodium chloride existed in high-magnesium, low-nickel oxide ore could make the NiO isolate from NiO-bearing minerals. The NiO reacts with Fe2O3 at high temperature to form NiFe2O4, which is conductive to the formation of Ni-Fe alloy during the reduction process.

Sodium fluoroacetate poisoning.

PubMed

Proudfoot, Alex T; Bradberry, Sally M; Vale, J Allister

2006-01-01

Sodium fluoroacetate was introduced as a rodenticide in the US in 1946. However, its considerable efficacy against target species is offset by comparable toxicity to other mammals and, to a lesser extent, birds and its use as a general rodenticide was therefore severely curtailed by 1990. Currently, sodium fluoroacetate is licensed in the US for use against coyotes, which prey on sheep and goats, and in Australia and New Zealand to kill unwanted introduced species. The extreme toxicity of fluoroacetate to mammals and insects stems from its similarity to acetate, which has a pivotal role in cellular metabolism. Fluoroacetate combines with coenzyme A (CoA-SH) to form fluoroacetyl CoA, which can substitute for acetyl CoA in the tricarboxylic acid cycle and reacts with citrate synthase to produce fluorocitrate, a metabolite of which then binds very tightly to aconitase, thereby halting the cycle. Many of the features of fluoroacetate poisoning are, therefore, largely direct and indirect consequences of impaired oxidative metabolism. Energy production is reduced and intermediates of the tricarboxylic acid cycle subsequent to citrate are depleted. Among these is oxoglutarate, a precursor of glutamate, which is not only an excitatory neurotransmitter in the CNS but is also required for efficient removal of ammonia via the urea cycle. Increased ammonia concentrations may contribute to the incidence of seizures. Glutamate is also required for glutamine synthesis and glutamine depletion has been observed in the brain of fluoroacetate-poisoned rodents. Reduced cellular oxidative metabolism contributes to a lactic acidosis. Inability to oxidise fatty acids via the tricarboxylic acid cycle leads to ketone body accumulation and worsening acidosis. Adenosine triphosphate (ATP) depletion results in inhibition of high energy-consuming reactions such as gluconeogenesis. Fluoroacetate poisoning is associated with citrate accumulation in several tissues, including the brain. Fluoride liberated from fluoroacetate, citrate and fluorocitrate are calcium chelators and there are both animal and clinical data to support hypocalcaemia as a mechanism of fluoroacetate toxicity. However, the available evidence suggests the fluoride component does not contribute. Acute poisoning with sodium fluoroacetate is uncommon. Ingestion is the major route by which poisoning occurs. Nausea, vomiting and abdominal pain are common within 1 hour of ingestion. Sweating, apprehension, confusion and agitation follow. Both supraventricular and ventricular arrhythmias have been reported and nonspecific ST- and T-wave changes are common, the QTc may be prolonged and hypotension may develop. Seizures are the main neurological feature. Coma may persist for several days. Although several possible antidotes have been investigated, they are of unproven value in humans. The immediate, and probably only, management of fluoroacetate poisoning is therefore supportive, including the correction of hypocalcaemia.

Paramagnetic or diamagnetic persistent currents? A topological point of view

NASA Astrophysics Data System (ADS)

Waintal, Xavier

2009-03-01

A persistent current flows at low temperatures in small conducting rings when they are threaded by a magnetic flux. I will discuss the sign of this persistent current (diamagnetic or paramagnetic response) in the special case of N electrons in a one dimensional ring [1]. One dimension is very special in the sense that the sign of the persistent current is entirely controlled by the topology of the system. I will establish lower bounds for the free energy in the presence of arbitrary electron-electron interactions and external potentials. Those bounds are the counterparts of upper bounds derived by Leggett using another topological argument. Rings with odd (even) numbers of polarized electrons are always diamagnetic (paramagnetic). The situation is more interesting with unpolarized electrons where Leggett upper bound breaks down: rings with N=4n exhibit either paramagnetic behavior or a superconductor-like current-phase relation. The topological argument provides a rigorous justification for the phenomenological Huckel rule which states that cyclic molecules with 4n + 2 electrons like benzene are aromatic while those with 4n electrons are not. [4pt] [1] Xavier Waintal, Geneviève Fleury, Kyryl Kazymyrenko, Manuel Houzet, Peter Schmitteckert, and Dietmar Weinmann Phys. Rev. Lett.101, 106804 (2008).

Brain MRS glutamine as a biomarker to guide therapy of hyperammonemic coma.

PubMed

O'Donnell-Luria, Anne H; Lin, Alexander P; Merugumala, Sai K; Rohr, Frances; Waisbren, Susan E; Lynch, Rebecca; Tchekmedyian, Vatche; Goldberg, Aaron D; Bellinger, Andrew; McFaline-Figueroa, J Ricardo; Simon, Tracey; Gershanik, Esteban F; Levy, Bruce D; Cohen, David E; Samuels, Martin A; Berry, Gerard T; Frank, Natasha Y

2017-05-01

Acute idiopathic hyperammonemia in an adult patient is a life-threatening condition often resulting in a rapid progression to irreversible cerebral edema and death. While ammonia-scavenging therapies lower blood ammonia levels, in comparison, clearance of waste nitrogen from the brain may be delayed. Therefore, we used magnetic resonance spectroscopy (MRS) to monitor cerebral glutamine levels, the major reservoir of ammonia, in a gastric bypass patient with hyperammonemic coma undergoing therapy with N-carbamoyl glutamate and the ammonia-scavenging agents, sodium phenylacetate and sodium benzoate. Improvement in mental status mirrored brain glutamine levels, as coma persisted for 48h after plasma ammonia normalized. We hypothesize that the slower clearance for brain glutamine levels accounts for the delay in improvement following initiation of treatment in cases of chronic hyperammonemia. We propose MRS to monitor brain glutamine as a noninvasive approach to be utilized for diagnostic and therapeutic monitoring purposes in adult patients presenting with idiopathic hyperammonemia. Copyright © 2017 Elsevier Inc. All rights reserved.

Food additives and behavior in 8- to 9-year-old children in Hong Kong: a randomized, double-blind, placebo-controlled trial.

PubMed

Lok, Kris Y W; Chan, Ruth S M; Lee, Vivian W Y; Leung, Patrick W; Leung, Cynthia; Leung, Jason; Woo, Jean

2013-01-01

To test the individual effect of artificial food colorings (AFCs) and a preservative on the behavior of the general Chinese population. One hundred thirty children (70 boys and 60 girls) in Hong Kong with a mean age of 8.64 years were enlisted to the study with a within-subject crossover between AFCs, a preservative (sodium benzoate), and a placebo capsule. Two behavior scores were used including the strengths and weaknesses of attention deficit hyperactivity disorder and normal behavior rating scale and the child behavior checklist-teacher report form. Capsule A containing AFCs and Capsule B containing sodium benzoate had no significant adverse effect compared with placebo in both behavior scores. This result persisted when analysis was restricted to children with 85% consumption of capsule (per protocol analysis). There seem to be no significant associations between AFCs and a preservative on Chinese children's behavior at the age of 8 to 9 years. Future directions and implications of this research are discussed.

Consumer attitudes and understanding of low-sodium claims on food: an analysis of healthy and hypertensive individuals.

PubMed

Wong, Christina L; Arcand, JoAnne; Mendoza, Julio; Henson, Spencer J; Qi, Ying; Lou, Wendy; L'Abbé, Mary R

2013-06-01

Sodium-related claims on food labels should facilitate lower-sodium food choices; however, consumer attitudes and understanding of such claims are unknown. We evaluated consumer attitudes and understanding of different types of sodium claims and the effect of having hypertension on responses to such claims. Canadian consumers (n = 506), with and without hypertension, completed an online survey that contained a randomized mock-package experiment, which tested 4 packages that differed only by the claims they carried as follows: 3 sodium claims (disease risk reduction, function, and nutrient-content claims) and a tastes-great claim (control). Participants answered the same questions on attitudes and understanding of claims after seeing each package. Food packages with any sodium claim resulted in more positive attitudes toward the claim and the product healthfulness than did packages with the taste control claim, although all mock packages were identical nutritionally. Having hypertension increased ratings related to product healthfulness and purchase intentions, but there was no difference in reported understanding between hypertensives and normotensives. In general, participants attributed additional health benefits to low-sodium products beyond the well-established relation of sodium and hypertension. Sodium claims have the potential to facilitate lower-sodium food choices. However, we caution that consumers do not seem to differentiate between different types of claims, but the nutritional profiles of foods that carry different sodium claims can potentially differ greatly in the current labeling environment. Additional educational efforts are needed to ensure that consumers do not attribute inappropriate health benefits to foods with low-sodium claims. This trial was registered at clinicaltrials.gov as NCT01764724.

Toddler foods, children's foods: assessing sodium in packaged supermarket foods targeted at children.

PubMed

Elliott, Charlene D; Conlon, Martin J

2011-03-01

To critically examine child-oriented packaged food products sold in Canada for their sodium content, and to assess them light of intake recommendations, the current policy context and suggested targets. Baby/toddler foods (n 186) and child-oriented packaged foods (n 354) were coded for various attributes (including sodium). Summary statistics were created for sodium, then the children's food products were compared with the UK Food Standards Agency (FSA) 'targets' for sodium in packaged foods. Also assessed were the products' per-serving sodium levels were assessed in light of the US Institute of Medicine's dietary reference intakes and Canada's Food Guide. Calgary, Alberta, Canada. None. Twenty per cent of products could be classified as having high sodium levels. Certain sub-categories of food (i.e. toddler entrées, children's packaged lunches, soups and canned pastas) were problematic. Significantly, when scaled in according to Schedule M or viewed in light of the serving sizes on the Nutrition Facts table, the sodium level in various dry goods products generally fell within, and below, the Adequate Intake (AI)/Tolerable Upper Intake Level (UL) band for sodium. When scaled in accordance with the UK FSA targets, however, none of the (same) products met the targets. In light of AI/UL thresholds based on age and per-serving cut-offs, packaged foodstuffs for youngsters fare relatively well, with the exception of some problematic areas. 'Stealth sodium' and 'subtle sodium' are important considerations; so is use of the FSA's scaling method to evaluate sodium content, because it is highly sensitive to the difference between the reference amount and the actual real-world serving size for the product being considered.

Process for vitrification of contaminated sodium oxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blair, H.T.; Mellinger, G.B.

1983-03-01

A glass composition was developed to accommodate 30 wt % sodium oxide and resist devitrification and leaching. An in-can melting process that is compatible with a comtaminated sodium calciner developed by Argonne National Laboratory was tested both on a laboratory and on an engineering scale and found to be viable. The Liquid Metal Fast Breeder Reactor experimental program continues to produce elemental sodium contaminated with radionuclides. This material is presently in temporary storage facilities because the current criterion will not permit alkali metals to be disposed of in shallow land burials. As a first step in treatment, Argonne National Laboratorymore » (ANL) has developed a calciner that will convert the sodium metal to an oxide. In work supported by the U.S. Department of Energy, Pacific Northwest Laboratory (PNL) is developing and demonstrating a process that is compatible with the calciner and facilities at ANL-West for incorporating sodium oxide into a glass. Glass, which normally contains sodium oxide, was chosen as the waste form because it is chemically durable and nondispersible. It is simple to produce, and the technology for incorporating nuclear wastes into glass is well developed.« less

Transcriptome analysis revealed anti-obesity effects of the Sodium Alginate in high-fat diet -induced obese mice.

PubMed

Wang, Xiong; Liu, Fang; Gao, Yuan; Xue, Chang-Hu; Li, Robert W; Tang, Qing-Juan

2018-04-10

Human obesity and overweight, caused by accumulated of fat, is the most commonly phenomenon from all over the world, especially in Western countries and Chinese mainland during the past three decades. Sodium Alginate, a polysaccharide extracted from brown seaweeds, has been proved its strong ability on body weight loss and anti-inflammatory response. However, no studies have been explored the effects of Sodium Alginate on colonic transcriptome, especially in obese individuals. Therefore, the current study was designed to detect whether Sodium Alginate could remit obesity and ease chronic metabolism disease through strengthening the bio-functionality of the lower intestine, particularly in colon. The data showed after Sodium Alginate gavaged for four weeks, the body weight, fat accumulation, triglyceride and total cholesterol were ameliorated in high fat diet induced obese mice. Sodium Alginate also improved the blood glucose level and lipopolysaccharides in serum. Furthermore, data from RNA sequence indicated that there were significantly changes in several genes, which involved in lipid metabolism and carbohydrate metabolism. In conclusion, these results suggested that Sodium Alginate could effectively suppress obesity and obesity related metabolic syndromes, due to the colonic transcriptome changes. Copyright © 2018. Published by Elsevier B.V.

Elucidation of pyrethroid and DDT receptor sites in the voltage-gated sodium channel.

PubMed

Zhorov, Boris S; Dong, Ke

2017-05-01

DDT and pyrethroid insecticides were among the earliest neurotoxins identified to act on voltage-gated sodium channels. In the 1960s, equipped with, at the time, new voltage-clamp techniques, Professor Narahashi and associates provided the initial evidence that DDT and allethrin (the first commercial pyrethroid insecticide) caused prolonged flow of sodium currents in lobster and squid giant axons. Over the next several decades, continued efforts by Prof. Narahashi's group as well as other laboratories led to a comprehensive understanding of the mechanism of action of DDT and pyrethroids on sodium channels. Fast forward to the 1990s, genetic, pharmacological and toxicological data all further confirmed voltage-gated sodium channels as the primary targets of DDT and pyrethroid insecticides. Modifications of the gating kinetics of sodium channels by these insecticides result in repetitive firing and/or membrane depolarization in the nervous system. This mini-review focuses on studies from Prof. Narahashi's pioneer work and more recent mutational and computational modeling analyses which collectively elucidated the elusive pyrethroid receptor sites as well as the molecular basis of differential sensitivities of insect and mammalian sodium channels to pyrethroids. Copyright © 2016 Elsevier B.V. All rights reserved.

Sumatriptan/Naproxen Sodium: A Review in Migraine.

PubMed

Syed, Yahiya Y

2016-01-01

Sumatriptan/naproxen sodium (Treximet®) is a fixed-dose combination of a serotonin 5-HT1B/1D receptor agonist (sumatriptan) and an NSAID (naproxen sodium), approved in the USA for the acute treatment of migraine with or without aura in adolescents and adults. In a randomized, phase 3 trial in adolescents, significantly more sumatriptan/naproxen sodium than placebo recipients were pain-free at 2 h. Similarly, in a pair of randomized phase 3 trials in adults, significantly more sumatriptan/naproxen sodium than placebo recipients had relief from migraine symptoms at 2 h, and the combination was more effective than individual components in terms of sustained (2-24 h) pain-free response rate. Sumatriptan/naproxen sodium was generally well tolerated, with ≤11 % of adolescents and ≤22 % of adults reporting treatment-related adverse events in the key clinical trials. The most common adverse reactions were nasopharyngitis, hot flushes and muscle tightness in adolescents, and dizziness, pain or pressure sensations, nausea, somnolence, dry mouth, dyspepsia and paraesthesia in adults. Based on current data, sumatriptan/naproxen sodium is a useful option for the acute treatment of migraine in adolescents and adults. The fixed-dose combination may reduce pill burden and improve adherence in some patients.

Mineralocorticoid receptor antagonism prevents hedonic deficits induced by a chronic sodium appetite.

PubMed

Morris, Michael J; Na, Elisa S; Johnson, Alan Kim

2010-04-01

Our laboratory has reported that manipulations that provoke a robust sodium appetite (e.g., sodium depletion, deoxycorticosterone acetate) decrease lateral hypothalamic self-stimulation (LHSS) reward if rats are denied access to hypertonic saline solutions. The following studies investigated the interaction between chronic sodium appetite and the renin-angiotensin-aldosterone system on LHSS reward. In Experiment 1, animals treated with the diuretic furosemide (20 mg/kg) when denied access to saline exhibited an increase in the current required to produce 50% of the maximum LHSS response rate (ECu50) 48 hr after extracellular volume depletion. Furosemide-depleted rats that were allowed to drink 0.3 M saline after depletion, or that were treated with the selective mineralocorticoid receptor (MR) antagonist spironolactone, which significantly reduced sodium appetite, did not show ECu50 changes. In Experiment 2 chronic intracerebroventricular administration of the selective MR antagonist RU 28318 (10 microg/microl/hr) prevented decreases in the ECu50 induced by deoxycorticosterone acetate-no salt treatment. We conclude that an unresolved sodium appetite will reduce responding for rewards and that experimental manipulations that reduce sodium appetite (e.g., access to saline or blockade of MR) decrease hedonic deficits.

Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pendleton, Justin; Bhavaraju, Sai; Priday, George

As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodiummore » management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent simulant from the Parsons process in the CRU. The modular CRU is easily scalable as a standalone system for caustic recycling, or for NTTS integration or for use as an In-Tank Treatment System to process sodium bearing waste to meet LLW processing needs at the Hanford site. The standalone pilot operation of the CRU to recycle sodium from NTCR effluent places the technology demonstration at TRL level 6. Multiple operations were performed with the CRU to process up to 500 gallons of the NTCR effluent and demonstrate an efficient separation of up to 70 % of the sodium without solids precipitation while producing 10 M caustic. Batch mode operation was conducted to study the effects of chemistry variation, establish the processing rate, and optimize the process operating conditions to recycle caustic from the NTCR effluent. The performance of the CRU was monitored by tracking the density parameter to control the concentration of caustic produced. Different levels of sodium were separated in tests from the effluent at a fixed operating current density and temperature. The voltage of the modules remained stable during the unit operation which demonstrated steady operation to separate sodium from the NTCR effluent. The sodium transfer current efficiency was measured in testing based on the concentration of caustic produced. Measurements showed a current efficiency of 99.8% for sodium transfer from the NTCR effluent to make sodium hydroxide. The sodium and hydroxide contents of the anolyte (NTCR feed) and catholyte (caustic product) were measured before and after each batch test. In two separate batch tests, samples were taken at different levels of sodium separation and analyzed to determine the stability of the NTCR effluent after sodium separation. The stability characteristics and changes in physical and chemical properties of the NTCR effluent chemistry after separation of sodium hydroxide as a function of storage time were evaluated. Parameters such as level of precipitated alumina, total alkalinity, analysis of Al, Na, K, Cs, Fe, OH, nitrate, nitrite, total dissolved and undissolved solids, viscosity, density, and other parameters of the NTCR effluent were measured. Changes in rheology and properties of NTCR stream to support downstream handling of the effluent after sodium separation was the basis for the analysis. The results show that the NTCR effluent is stable without the precipitation of aluminum hydroxide after 70% of the sodium was separated from the effluent. (authors)« less

A Conserved Bicycle Model for Circadian Clock Control of Membrane Excitability

PubMed Central

Flourakis, Matthieu; Kula-Eversole, Elzbieta; Hutchison, Alan L.; Han, Tae Hee; Aranda, Kimberly; Moose, Devon L.; White, Kevin P.; Dinner, Aaron R.; Lear, Bridget C.; Ren, Dejian; Diekman, Casey O.; Raman, Indira M.; Allada, Ravi

2015-01-01

Summary Circadian clocks regulate membrane excitability in master pacemaker neurons to control daily rhythms of sleep and wake. Here we find that two distinctly timed electrical drives collaborate to impose rhythmicity on Drosophila clock neurons. In the morning, a voltage-independent sodium conductance via the NA/NALCN ion channel depolarizes these neurons. This current is driven by the rhythmic expression of NCA localization factor-1, linking the molecular clock to ion channel function. In the evening, basal potassium currents peak to silence clock neurons. Remarkably, daily antiphase cycles of sodium and potassium currents also drive mouse clock neuron rhythms. Thus, we reveal an evolutionarily ancient strategy for the neural mechanisms that govern daily sleep and wake. PMID:26276633

Proportional-Integral-Derivative (PID) Temperature Control and Data Acquisition System for Faraday Filter based Sodium Spectrometer

NASA Astrophysics Data System (ADS)

Semerjyan, Vardan; Yuan, Tao

2011-04-01

Sodium (Na) Faraday filters based spectrometer is a relatively new instrument to study sodium nightglow as well as sodium and oxygen chemistry in the mesopause region. Successful spectrometer measurement demands highly accurate control of filter temperature. The ideal, long-term operation site for the Na spectrometer is an isolated location with minimum nocturnal sky background. Thus, the remote control of the filter temperature is a requirement for such operation, whereas current temperature controllers can only be operated manually. The proposed approach is aimed to not only enhance the temperature control, but also achieve spectrometer's remote and autonomous operation. In the meantime, the redesign should relief the burden of the cost for multi temperature controllers. The program will give to the operator flexibility in setting the operation temperatures of the Faraday filters, monitoring the temperature variations, and logging the data during the operation. Research will make diligent efforts to attach preliminary data analysis subroutine to the main control program. The real-time observation results will be posted online after the observation is completed. This approach also can be a good substitute for the temperature control system currently used to run the Lidar system at Utah State University (USU).

MoTe2, A novel anode material for sodium ion battery

NASA Astrophysics Data System (ADS)

Panda, Manas Ranjan; Anish Raj, K.; Bao, Qiaoliang; Mitra, Sagar

2018-04-01

2D layered transition metal dichalcogenides are considered as a potential anode for sodium-ion batteries due to their high specific capacity, structural stability and its well-developed two-dimensional layers. 2D layered structure Molybdenum ditelluride (MoTe2) provides a superior Na-ion storage properties in sodium ion battery due to its comparative more interlayer spacing (0.699 nm). In the current study MoTe2 polycrystalline powder sample has been prepared by solid state reaction process, the structural and morphological studies have been carried out by XRD, FE-SEM and EDS etc. XRD study revealsthe well crystalline structure of the material having hexagonal structure. FE-SEM and EDS studies depict the uniformflakes like structure of the material. When it is tested as sodium-ion battery anode by applying a potential window 0.1-2.5 V, the material demonstrates a high capacity and high power performances. The as prepared MoTe2 shows an initial discharge capacity of 376 mA h g-1 and a corresponding discharge capacity of 303 mA h g-1 after the 50th cycle at a current density of 500 mA g-1.

Drought Persistence Errors in Global Climate Models

NASA Astrophysics Data System (ADS)

Moon, H.; Gudmundsson, L.; Seneviratne, S. I.

2018-04-01

The persistence of drought events largely determines the severity of socioeconomic and ecological impacts, but the capability of current global climate models (GCMs) to simulate such events is subject to large uncertainties. In this study, the representation of drought persistence in GCMs is assessed by comparing state-of-the-art GCM model simulations to observation-based data sets. For doing so, we consider dry-to-dry transition probabilities at monthly and annual scales as estimates for drought persistence, where a dry status is defined as negative precipitation anomaly. Though there is a substantial spread in the drought persistence bias, most of the simulations show systematic underestimation of drought persistence at global scale. Subsequently, we analyzed to which degree (i) inaccurate observations, (ii) differences among models, (iii) internal climate variability, and (iv) uncertainty of the employed statistical methods contribute to the spread in drought persistence errors using an analysis of variance approach. The results show that at monthly scale, model uncertainty and observational uncertainty dominate, while the contribution from internal variability is small in most cases. At annual scale, the spread of the drought persistence error is dominated by the statistical estimation error of drought persistence, indicating that the partitioning of the error is impaired by the limited number of considered time steps. These findings reveal systematic errors in the representation of drought persistence in current GCMs and suggest directions for further model improvement.

Mesoporous Prussian blue analogues: template-free synthesis and sodium-ion battery applications.

PubMed

Yue, Yanfeng; Binder, Andrew J; Guo, Bingkun; Zhang, Zhiyong; Qiao, Zhen-An; Tian, Chengcheng; Dai, Sheng

2014-03-17

The synthesis of mesoporous Prussian blue analogues through a template-free methodology and the application of these mesoporous materials as high-performance cathode materials in sodium-ion batteries is presented. Crystalline mesostructures were produced through a synergistically coupled nanocrystal formation and aggregation mechanism. As cathodes for sodium-ion batteries, the Prussian blue analogues all show a reversible capacity of 65 mA h g-1 at low current rate and show excellent cycle stability. The reported method stands as an environmentally friendly and low-cost alternative to hard or soft templating for the fabrication of mesoporous materials.

Attenuated effect of tungsten carbide nanoparticles on voltage-gated sodium current of hippocampal CA1 pyramidal neurons.

PubMed

Shan, Dehong; Xie, Yongling; Ren, Guogang; Yang, Zhuo

2013-02-01

Nanomaterials and relevant products are now being widely used in the world, and their safety becomes a great concern for the general public. Tungsten carbide nanoparticles (nano-WC) are widely used in metallurgy, aeronautics and astronautics, however our knowledge regarding the influence of nano-WC on neurons is still lacking. The aim of this study was to investigate the impact of nano-WC on tetrodotoxin (TTX)-sensitive voltage-activated sodium current (I(Na)) of hippocampal CA1 pyramidal neurons. Results showed that acute exposure of nano-WC attenuated the peak amplitudes of I(Na) in a concentration-dependent manner. The minimal effective concentration was 10(-5)g/ml. The exposure of nano-WC significantly decreased current amplitudes of the current-voltage curves of I(Na) from -50 to+50 mV, shifted the steady-state activation and inactivation curves of I(Na) negatively and delayed the recovery of I(Na) from inactivation state. After exposure to nano-WC, the peak amplitudes, overshoots and the V-thresholds of action potentials (APs) were markedly reduced. These results suggested that exposure of nano-WC could influence some characteristics of APs evoked from the hippocampal CA1 neurons by modifying the kinetics of voltage-gated sodium channels (VGSCs). Copyright © 2012 Elsevier Ltd. All rights reserved.

Potential risk and sodium content of children's ready-to-eat foods distributed at major amusement parks in Korea.

PubMed

Lee, N-Y; Park, S-Y; Lee, Y-M; Choi, S-Y; Jeong, S-H; Chung, M-S; Chang, Y-S; Choi, S-H; Bae, D-H; Ha, S-D

2013-01-01

This study was conducted to help better understand the current sodium intake of Korean children and to establish children's good eating habits through investigation of the sodium content of ready-to-eat foods collected from nine major amusement parks in Korea. The sodium content of a total of 322 products was analysed by using ICP and then the potential risk based on the recommended daily intake of sodium as described in the Korean dietary reference intakes was determined. The results showed that sodium content was the lowest in muffins (245 mg/100 g) and the highest in seasoned dried filefish (1825 mg/100 g). The average amounts of sodium per serving of seasoned dried filefish, tteokbokki and fish paste were 1150, 1248 and 1097 mg, respectively. The values were above 50% of the daily intake of sodium recommended by the Korean dietary reference intake. The ready-to-eat foods were also classified into high, medium and low sodium content on the basis of standards recommended by the Korean Food and Drug Administration. Most snacks were classified as high sodium foods because they exceeded "300 mg (84.5% of the total daily allowance)". Furthermore, the meal substitution foods such as kimbab, tteokbokki, mandus, sandwiches and hamburgers exceeded "600 mg (90.3% of the total daily allowance)" and were also classified as high sodium foods. In addition, ready-to-eat foods in amusement parks are similar to foods eaten on streets and foods around school zones, which contain high sodium content; thus, the intake frequency might be high, which would induce high risk to children health. Koreans already consume a high amount of sodium daily via their usual diets. So, the sodium content in snacks and substitution foods needs to be reduced. Consequently, this study noted that parents and guardians should carefully consider their children's consumption of ready-to-eat foods from Korean amusement parks.

Creation of the NaSCoRD Database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denman, Matthew R.; Jankovsky, Zachary Kyle; Stuart, William

This report was written as part of a United States Department of Energy (DOE), Office of Nuclear Energy, Advanced Reactor Technologies program funded project to re-create the capabilities of the legacy Centralized Reliability Database Organization (CREDO) database. The CREDO database provided a record of component design and performance documentation across various systems that used sodium as a working fluid. Regaining this capability will allow the DOE complex and the domestic sodium reactor industry to better understand how previous systems were designed and built for use in improving the design and operations of future loops. The contents of this report include:more » overview of the current state of domestic sodium reliability databases; summary of the ongoing effort to improve, understand, and process the CREDO information; summary of the initial efforts to develop a unified sodium reliability database called the Sodium System Component Reliability Database (NaSCoRD); and explain both how potential users can access the domestic sodium reliability databases and the type of information that can be accessed from these databases.« less

Ethanolic extract of Aconiti Brachypodi Radix attenuates nociceptive pain probably via inhibition of voltage-dependent Na⁺ channel.

PubMed

Ren, Wei; Yuan, Lin; Li, Jun; Huang, Xian-Ju; Chen, Su; Zou, Da-Jiang; Liu, Xiangming; Yang, Xin-Zhou

2012-01-01

Aconiti Brachypodi Radix, belonging to the genus of Aconitum (Family Ranunculaceae), are used clinically as anti-rheumatic, anti-inflammatory and anti-nociceptive in traditional medicine of China. However, its mechanism and influence on nociceptive threshold are unknown and need further investigation. The analgesic effects of ethanolic extract of Aconiti Brachypodi Radix (EABR) were thus studied in vivo and in vitro. Three pain models in mice were used to assess the effect of EABR on nociceptive threshold. In vitro study was conducted to clarify the modulation of the extract on the tetrodotoxin-sensitive (TTX-S) sodium currents in rat's dorsal root ganglion (DRG) neurons using whole-cell patch clamp technique. The results showed that EABR (5-20 mg/kg, i.g.) could produce dose-dependent analgesic effect on hot-plate tests as well as writhing response induced by acetic acid. In addition, administration of 2.5-10 mg/kg EABR (i.g.) caused significant decrease in pain responses in the first and second phases of formalin test without altering the PGE₂ production in the hind paw of the mice. Moreover, EABR (10 µg/ml -1 mg/ml) could suppress TTX-S voltage-gated sodium currents in a dose-dependent way, indicating the underlying electrophysiological mechanism of the analgesic effect of the folk plant medicine. Collectively, our results indicated that EABR has analgesic property in three pain models and useful influence on TTX-S sodium currents in DRG neurons, suggesting that the interference with pain messages caused by the modulation of EABR on TTX-S sodium currents in DRG neurones may explain some of its analgesic effect.

Early pregnancy termination with intravaginally administered sodium chloride solution-moistened misoprostol tablets: historical comparison with mifepristone and oral misoprostol.

PubMed

Jain, J K; Meckstroth, K R; Mishell, D R

1999-12-01

The purpose of this study was to compare the abortifacient effect of intravaginally administered moistened misoprostol tablets with that of the combination regimen of mifepristone and oral misoprostol. One hundred women at

Abnormal sodium current properties contribute to cardiac electrical and contractile dysfunction in a mouse model of myotonic dystrophy type 1.

PubMed

Algalarrondo, Vincent; Wahbi, Karim; Sebag, Frédéric; Gourdon, Geneviève; Beldjord, Chérif; Azibi, Kamel; Balse, Elise; Coulombe, Alain; Fischmeister, Rodolphe; Eymard, Bruno; Duboc, Denis; Hatem, Stéphane N

2015-04-01

Myotonic dystrophy type 1 (DM1) is the most common neuromuscular disorder and is associated with cardiac conduction defects. However, the mechanisms of cardiac arrhythmias in DM1 are unknown. We tested the hypothesis that abnormalities in the cardiac sodium current (INa) are involved, and used a transgenic mouse model reproducing the expression of triplet expansion observed in DM1 (DMSXL mouse). The injection of the class-I antiarrhythmic agent flecainide induced prominent conduction abnormalities and significantly lowered the radial tissular velocities and strain rate in DMSXL mice compared to WT. These abnormalities were more pronounced in 8-month-old mice than in 3-month-old mice. Ventricular action potentials recorded by standard glass microelectrode technique exhibited a lower maximum upstroke velocity [dV/dt](max) in DMSXL. This decreased [dV/dt](max) was associated with a 1.7 fold faster inactivation of INa in DMSXL myocytes measured by the whole-cell patch-clamp technique. Finally in the DMSXL mouse, no mutation in the Scn5a gene was detected and neither cardiac fibrosis nor abnormalities of expression of the sodium channel protein were observed. Therefore, alterations in the sodium current markedly contributed to electrical conduction block in DM1. This result should guide pharmaceutical and clinical research toward better therapy for the cardiac arrhythmias associated with DM1. Copyright © 2014 Elsevier B.V. All rights reserved.

The technical report on sodium intake and cardiovascular disease in low- and middle-income countries by the joint working group of the World Heart Federation, the European Society of Hypertension and the European Public Health Association.

PubMed

Mancia, Giuseppe; Oparil, Suzanne; Whelton, Paul K; McKee, Martin; Dominiczak, Anna; Luft, Friedrich C; AlHabib, Khalid; Lanas, Fernando; Damasceno, Albertino; Prabhakaran, Dorairaj; La Torre, Giuseppe; Weber, Michael; O'Donnell, Martin; Smith, Sidney C; Narula, Jagat

2017-03-07

Ingestion of sodium is essential to health, but excess sodium intake is a risk factor for hypertension and cardiovascular disease. Defining an optimal range of sodium intake in populations has been challenging and controversial. Clinical trials evaluating the effect of sodium reduction on blood pressure have shown blood pressure lowering effects down to sodium intake of less than 1.5 g/day. Findings from these blood pressure trials form the basis for current guideline recommendations to reduce sodium intake to less than 2.3 g/day. However, these clinical trials employed interventions that are not feasible for population-wide implementation (i.e. feeding studies or intensive behavioural interventions), particularly in low and middle-income countries. Prospective cohort studies have identified the optimal range of sodium intake to reside in the moderate range (3-5 g/day), where the risk of cardiovascular disease and death is lowest. Therefore, there is consistent evidence from clinical trials and observational studies to support reducing sodium intake to less than 5 g/day in populations, but inconsistent evidence for further reductions below a moderate intake range (3-5 g/day). Unfortunately, there are no large randomized controlled trials comparing low sodium intake (< 3 g/day) to moderate sodium intake (3-5 g/day) in general populations to determine the net clinical effects of low sodium intake. Until such trials are completed, it is likely that controversy about optimal sodium intake range will continue. This working group calls for the completion of large definitive clinical trials to clarify the range of sodium intake for optimal cardiovascular health within the moderate to low intake range. We support interventions to reduce sodium intake in populations who consume high sodium intake (> 5 g/day), which should be embedded within an overall healthy dietary pattern. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

Dysbalance of Astrocyte Calcium under Hyperammonemic Conditions

PubMed Central

Haack, Nicole; Dublin, Pavel; Rose, Christine R.

2014-01-01

Increased brain ammonium (NH4 +/NH3) plays a central role in the manifestation of hepatic encephalopathy (HE), a complex syndrome associated with neurological and psychiatric alterations, which is primarily a disorder of astrocytes. Here, we analysed the influence of NH4 +/NH3 on the calcium concentration of astrocytes in situ and studied the underlying mechanisms of NH4 +/NH3-evoked calcium changes, employing fluorescence imaging with Fura-2 in acute tissue slices derived from different regions of the mouse brain. In the hippocampal stratum radiatum, perfusion with 5 mM NH4 +/NH3 for 30 minutes caused a transient calcium increase in about 40% of astrocytes lasting about 10 minutes. Furthermore, the vast majority of astrocytes (∼90%) experienced a persistent calcium increase by ∼50 nM. This persistent increase was already evoked at concentrations of 1–2 mM NH4 +/NH3, developed within 10–20 minutes and was maintained as long as the NH4 +/NH3 was present. Qualitatively similar changes were observed in astrocytes of different neocortical regions as well as in cerebellar Bergmann glia. Inhibition of glutamine synthetase resulted in significantly larger calcium increases in response to NH4 +/NH3, indicating that glutamine accumulation was not a primary cause. Calcium increases were not mimicked by changes in intracellular pH. Pharmacological inhibition of voltage-gated sodium channels, sodium-potassium-chloride-cotransporters (NKCC), the reverse mode of sodium/calcium exchange (NCX), AMPA- or mGluR5-receptors did not dampen NH4 +/NH3-induced calcium increases. They were, however, significantly reduced by inhibition of NMDA receptors and depletion of intracellular calcium stores. Taken together, our measurements show that sustained exposure to NH4 +/NH3 causes a sustained increase in intracellular calcium in astrocytes in situ, which is partly dependent on NMDA receptor activation and on release of calcium from intracellular stores. Our study furthermore suggests that dysbalance of astrocyte calcium homeostasis under hyperammonemic conditions is a widespread phenomenon, which might contribute to the disturbance of neurotransmission during HE. PMID:25153709

Calcium Homeostasis Modulator 1-Like Currents in Rat Fungiform Taste Cells Expressing Amiloride-Sensitive Sodium Currents.

PubMed

Bigiani, Albertino

2017-05-01

Salt reception by taste cells is still the less understood transduction process occurring in taste buds, the peripheral sensory organs for the detection of food chemicals. Although there is evidence suggesting that the epithelial sodium channel (ENaC) works as sodium receptor, yet it is not clear how salt-detecting cells signal the relevant information to nerve endings. Taste cells responding to sweet, bitter, and umami substances release ATP as neurotransmitter through a nonvesicular mechanism. Three different channel proteins have been proposed as conduit for ATP secretion: pannexin channels, connexin hemichannels, and calcium homeostasis modulator 1 (CALHM1) channels. In heterologous expression systems, these channels mediate outwardly rectifying membrane currents with distinct biophysical and pharmacological properties. I therefore tested whether also salt-detecting taste cells were endowed with these currents. To this aim, I applied the patch-clamp techniques to single cells in isolated taste buds from rat fungiform papillae. Salt-detecting cells were functionally identified by exploiting the effect of amiloride, which induces a current response by shutting down ENaCs. I looked for the presence of outwardly rectifying currents by using appropriate voltage-clamp protocols and specific pharmacological tools. I found that indeed salt-detecting cells possessed these currents with properties consistent with the presence, at least in part, of CALHM1 channels. Unexpectedly, CALHM1-like currents in taste cells were potentiated by known blockers of pannexin, suggesting a possible inhibitory action of this protein on CALMH1. These findings indicate that communication between salt-detecting cells and nerve endings might involve ATP release by CALMH1 channels. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Native pyroglutamation of huwentoxin-IV: a post-translational modification that increases the trapping ability to the sodium channel.

PubMed

Rong, Mingqiang; Duan, Zhigui; Chen, Juliang; Li, Jianglin; Xiao, Yuchen; Liang, Songping

2013-01-01

Huwentoxin-IV (HWTX-IV), a tetrodotoxin-sensitive (TTX-s) sodium channel antagonist, is found in the venom of the Chinese spider Ornithoctonus huwena. A naturally modified HWTX-IV (mHWTX-IV), having a molecular mass 18 Da lower than HWTX-IV, has also been isolated from the venom of the same spider. By a combination of enzymatic fragmentation and MS/MS de novo sequencing, mHWTX-IV has been shown to have the same amino acid sequence as that of HWTX-IV, except that the N-terminal glutamic acid replaced by pyroglutamic acid. mHWTX-IV inhibited tetrodotoxin-sensitive voltage-gated sodium channels of dorsal root ganglion neurons with an IC50 nearly equal to native HWTX-IV. mHWTX-IV showed the same activation and inactivation kinetics seen for native HWTX-IV. In contrast with HWTX-IV, which dissociates at moderate voltage depolarization voltages (+50 mV, 180000 ms), mHWTX-IV inhibition of TTX-sensitive sodium channels is not reversed by strong depolarization voltages (+200 mV, 500 ms). Recovery of Nav1.7current was voltage-dependent and was induced by extreme depolarization in the presence of HWTX-IV, but no obvious current was elicited after application of mHWTX-IV. Our data indicate that the N-terminal modification of HWTX-IV gives the peptide toxin a greater ability to trap the voltage sensor in the sodium channel. Loss of a negative charge, caused by cyclization at the N-terminus, is a possible reason why the modified toxin binds much stronger. To our knowledge, this is the first report of a pyroglutamic acid residue in a spider toxin; this modification seems to increase the trapping ability of the voltage sensor in the sodium channel.

Native Pyroglutamation of Huwentoxin-IV: A Post-Translational Modification that Increases the Trapping Ability to the Sodium Channel

PubMed Central

Rong, Mingqiang; Duan, Zhigui; Chen, Juliang; Li, Jianglin; Xiao, Yuchen; Liang, Songping

2013-01-01

Huwentoxin-IV (HWTX-IV), a tetrodotoxin-sensitive (TTX-s) sodium channel antagonist, is found in the venom of the Chinese spider Ornithoctonus huwena. A naturally modified HWTX-IV (mHWTX-IV), having a molecular mass 18 Da lower than HWTX-IV, has also been isolated from the venom of the same spider. By a combination of enzymatic fragmentation and MS/MS de novo sequencing, mHWTX-IV has been shown to have the same amino acid sequence as that of HWTX-IV, except that the N-terminal glutamic acid replaced by pyroglutamic acid. mHWTX-IV inhibited tetrodotoxin-sensitive voltage-gated sodium channels of dorsal root ganglion neurons with an IC50 nearly equal to native HWTX-IV. mHWTX-IV showed the same activation and inactivation kinetics seen for native HWTX-IV. In contrast with HWTX-IV, which dissociates at moderate voltage depolarization voltages (+50 mV, 180000 ms), mHWTX-IV inhibition of TTX-sensitive sodium channels is not reversed by strong depolarization voltages (+200 mV, 500 ms). Recovery of Nav1.7current was voltage-dependent and was induced by extreme depolarization in the presence of HWTX-IV, but no obvious current was elicited after application of mHWTX-IV. Our data indicate that the N-terminal modification of HWTX-IV gives the peptide toxin a greater ability to trap the voltage sensor in the sodium channel. Loss of a negative charge, caused by cyclization at the N-terminus, is a possible reason why the modified toxin binds much stronger. To our knowledge, this is the first report of a pyroglutamic acid residue in a spider toxin; this modification seems to increase the trapping ability of the voltage sensor in the sodium channel. PMID:23826086

Topological data analysis as a morphometric method: using persistent homology to demarcate a leaf morphospace

USDA-ARS?s Scientific Manuscript database

Current morphometric methods that comprehensively measure shape cannot compare the disparate leaf shapes found in flowering plants and are sensitive to processing artifacts. Here we describe a persistent homology approach to measuring shape. Persistent homology is a topological method (concerned wit...

The Role of Persistence at Preschool Age in Academic Skills at Kindergarten

ERIC Educational Resources Information Center

Mokrova, Irina L.; O'Brien, Marion; Calkins, Susan D.; Leerkes, Esther M.; Marcovitch, Stuart

2013-01-01

The current study examined the role of preschoolers' motivation, operationalized as persistence, in the formation of language and math skills at kindergarten. The participants were 263 children from diverse ethnic and socio-economic backgrounds. Demographic information, child persistence, and early cognitive-linguistic skills were assessed at…

Dietary sodium reduction in New Zealand: influence of the Tick label.

PubMed

Ning, Sherry X; Mainvil, Louise A; Thomson, Rachel K; McLean, Rachel M

2017-01-01

The Tick programme of the National Heart Foundation (NHF) is the longest standing voluntary front of pack signpost nutrition logo in New Zealand. It provides a platform for collaboration with the food industry to encourage development of healthier products. This study evaluated the impact of the Tick programme on sodium in processed food. Fifty-two Tick programme products from food categories known to contribute substantially to sodium intake were identified. Sales volumes (kg) from January 2011 to December 2013 were multiplied by changes in sodium content over that time, producing an estimate of programme impact. Five semi-structured interviews with industry representatives were conducted, to look at other influences for sodium reduction, and themes identified through methods of thematic analysis. Over the period, the Tick programme influenced food companies to remove approximately 16 tonnes of salt through the reformulation and formulation of 52 Tick-approved breakfast cereals, edible oil spreads, cooking sauces and processed poultry products. Other factors influencing sodium reduction reported by company representatives included increased consumer and industry interest in healthier product nutrition profiles and other sodium reduction programmes targeting reformulation/formulation. The Tick remains a credible and well-recognized brand and may provide a competitive edge for participating food manufacturers in the current market. The Tick programme is effective in influencing industry to reduce sodium in processed foods in New Zealand. The combined impact of the Tick and other NHF programmes has the potential to reduce population sodium intake and improve health outcomes.

Sodium-to-Potassium Ratio and Blood Pressure, Hypertension, and Related Factors12

PubMed Central

Perez, Vanessa; Chang, Ellen T.

2014-01-01

The potential cost-effectiveness and feasibility of dietary interventions aimed at reducing hypertension risk are of considerable interest and significance in public health. In particular, the effectiveness of restricted sodium or increased potassium intake on mitigating hypertension risk has been demonstrated in clinical and observational research. The role that modified sodium or potassium intake plays in influencing the renin-angiotensin system, arterial stiffness, and endothelial dysfunction remains of interest in current research. Up to the present date, no known systematic review has examined whether the sodium-to-potassium ratio or either sodium or potassium alone is more strongly associated with blood pressure and related factors, including the renin-angiotensin system, arterial stiffness, the augmentation index, and endothelial dysfunction, in humans. This article presents a systematic review and synthesis of the randomized controlled trials and observational research related to this issue. The main findings show that, among the randomized controlled trials reviewed, the sodium-to-potassium ratio appears to be more strongly associated with blood pressure outcomes than either sodium or potassium alone in hypertensive adult populations. Recent data from the observational studies reviewed provide additional support for the sodium-to-potassium ratio as a superior metric to either sodium or potassium alone in the evaluation of blood pressure outcomes and incident hypertension. It remains unclear whether this is true in normotensive populations and in children and for related outcomes including the renin-angiotensin system, arterial stiffness, the augmentation index, and endothelial dysfunction. Future study in these populations is warranted. PMID:25398734

The CSSL (combined sporadic structures and layers) payload: In situ observations of mesospheric sodium and related parameters

NASA Technical Reports Server (NTRS)

Machuga, David W.; Kane, Timothy J.; Wheeler, Timothy F.; Croskey, Charles L.; Mathews, John D.; Mitchell, John D.

1997-01-01

The objectives, design and results of the sensor systems for the combined sporadic structures and layers (CSSL) payload are analyzed. The CSSL main objectives were to: validate current models of mesospheric sodium chemistry; explore the relationship between turbulence and Na fluctuations; and to explore the relationship between high latitude electric fields and the formation of Na anomalies.

Current methodology to assess bioequivalence of levothyroxine sodium products is inadequate.

PubMed

Blakesley, Vicky A

2005-03-30

Levothyroxine sodium is a drug with a narrow therapeutic index for which an individual patient must have his or her dose carefully titrated to achieve the necessary therapeutic effect. In addition, exogenous levothyroxine cannot be distinguished from the endogenously produced hormone. Since 2004, generic formulations have been approved for the most frequently prescribed brands of levothyroxine sodium. This review examines the methodology and statistical acceptance criteria and summarizes findings of a previously published relative bioavailability study that brings into question the use of standard criteria to assess bioequivalence of levothyroxine sodium. The key findings reviewed were the following: (1) in the absence of baseline correction for endogenous T4 levels, products that differed by as much as 25% to 33% would be declared bioequivalent; (2) the use of baseline correction reduced the likelihood of declaring products bioequivalent when they actually differed by 25% to 33%; (3) even with baseline correction, products that differed by 12.5% would be declared bioequivalent; and (4) there was evidence of significant carryover from one dosing period to the next even with washout periods of up to 53 days. In conclusion, the current recommended methodology in the United States to assess bioequivalence for levothyroxine sodium products is inadequate to differentiate products that differ by 12.5%, a clinically relevant difference. Recommendations are made for modifications to the criteria that could improve the likelihood that products that differ by a clinically significant amount in their bioavailability would not be accepted as bioequivalent.

Associations Between Excessive Sodium Intake and Smoking and Alcohol Intake Among Korean Men: KNHANES V.

PubMed

Choi, Kyung-Hwa; Park, Myung-Sook; Kim, Jung Ae; Lim, Ji-Ae

2015-12-08

In this study, we evaluated the associations of smoking and alcohol intake, both independently and collectively, with sodium intake in Korean men. Subjects (6340 men) were from the fifth Korean National Health Examination Survey (2010-2012). Smoking-related factors included smoking status, urinary cotinine level, and pack-years of smoking. Food intake was assessed using a 24-h recall. The odds of excessive sodium intake were estimated using survey logistic regression analysis. The smoking rate was 44.1%. The geometric mean of the urinary cotinine level was 0.05 µg/mL, and the median (min-max) pack-years of smoking was 13.2 (0-180). When adjusted for related factors, the odds (95% confidence interval) of excessive sodium intake were 1.54 (1.00, 2.37), 1.55 (1.23, 1.94), 1.44 (1.07, 1.95), and 1.37 (1.11, 1.68) times higher in the group exposed to smoking and drinking than in the group that never smoked nor drank, the group that never smoked and drank <5 times per month, the group that did not currently smoke and never drank, and the group that did not currently smoke or drink <5 times per month, respectively. There was an interaction effect between smoking and alcohol intake (p-interaction = 0.02). The results suggest that simultaneous exposure to smoking and alcohol intake is associated with increased odds of excessive sodium intake.

Associations Between Excessive Sodium Intake and Smoking and Alcohol Intake Among Korean Men: KNHANES V

PubMed Central

Choi, Kyung-Hwa; Park, Myung-Sook; Kim, Jung Ae; Lim, Ji-Ae

2015-01-01

In this study, we evaluated the associations of smoking and alcohol intake, both independently and collectively, with sodium intake in Korean men. Subjects (6340 men) were from the fifth Korean National Health Examination Survey (2010–2012). Smoking-related factors included smoking status, urinary cotinine level, and pack-years of smoking. Food intake was assessed using a 24-h recall. The odds of excessive sodium intake were estimated using survey logistic regression analysis. The smoking rate was 44.1%. The geometric mean of the urinary cotinine level was 0.05 µg/mL, and the median (min–max) pack-years of smoking was 13.2 (0–180). When adjusted for related factors, the odds (95% confidence interval) of excessive sodium intake were 1.54 (1.00, 2.37), 1.55 (1.23, 1.94), 1.44 (1.07, 1.95), and 1.37 (1.11, 1.68) times higher in the group exposed to smoking and drinking than in the group that never smoked nor drank, the group that never smoked and drank <5 times per month, the group that did not currently smoke and never drank, and the group that did not currently smoke or drink <5 times per month, respectively. There was an interaction effect between smoking and alcohol intake (p-interaction = 0.02). The results suggest that simultaneous exposure to smoking and alcohol intake is associated with increased odds of excessive sodium intake. PMID:26670236

Food labeling; nutrient content claims, definition of sodium levels for the term "healthy." Final rule.

PubMed

2005-09-29

The Food and Drug Administration (FDA) is amending its regulations concerning the maximum sodium levels permitted for foods that bear the implied nutrient content claim "healthy." The agency is retaining the currently effective, less restrictive, "first-tier" sodium level requirements for all food categories, including individual foods (480 milligrams (mg)) and meals and main dishes (600 mg), and is dropping the "second-tier" (more restrictive) sodium level requirements for all food categories. Based on the comments received about technological barriers to reducing sodium in processed foods and poor sales of products that meet the second-tier sodium level, the agency has determined that requiring the more restrictive sodium levels would likely inhibit the development of new "healthy" food products and risk substantially eliminating existing "healthy" products from the marketplace. After reviewing the comments and evaluating the data from various sources, FDA has become convinced that retaining the higher first-tier sodium level requirements for all food products bearing the term "healthy" will encourage the manufacture of a greater number of products that are consistent with dietary guidelines for a variety of nutrients. The agency has also revised the regulatory text of the "healthy" regulation to clarify the scope and meaning of the regulation and to reformat the nutrient content requirements for "healthy" into a more readable set of tables, consistent with the Presidential Memorandum instructing that regulations be written in plain language.

Dietary Impact of Adding Potassium Chloride to Foods as a Sodium Reduction Technique.

PubMed

van Buren, Leo; Dötsch-Klerk, Mariska; Seewi, Gila; Newson, Rachel S

2016-04-21

Potassium chloride is a leading reformulation technology for reducing sodium in food products. As, globally, sodium intake exceeds guidelines, this technology is beneficial; however, its potential impact on potassium intake is unknown. Therefore, a modeling study was conducted using Dutch National Food Survey data to examine the dietary impact of reformulation (n = 2106). Product-specific sodium criteria, to enable a maximum daily sodium chloride intake of 5 grams/day, were applied to all foods consumed in the survey. The impact of replacing 20%, 50% and 100% of sodium chloride from each product with potassium chloride was modeled. At baseline median, potassium intake was 3334 mg/day. An increase in the median intake of potassium of 453 mg/day was seen when a 20% replacement was applied, 674 mg/day with a 50% replacement scenario and 733 mg/day with a 100% replacement scenario. Reformulation had the largest impact on: bread, processed fruit and vegetables, snacks and processed meat. Replacement of sodium chloride by potassium chloride, particularly in key contributing product groups, would result in better compliance to potassium intake guidelines (3510 mg/day). Moreover, it could be considered safe for the general adult population, as intake remains compliant with EFSA guidelines. Based on current modeling potassium chloride presents as a valuable, safe replacer for sodium chloride in food products.

Sivelestat sodium hydrate improves post-traumatic knee osteoarthritis through nuclear factor-κB in a rat model.

PubMed

Yu, Xiaofeng; Zhao, Lijun; Yu, Zhiping; Yu, Changzheng; Bi, Jianfei; Sun, Binglong; Cong, Haibo

2017-08-01

As a specific inhibitor of neutrophil elastase, sivelestat sodium hydrate has primarily been used in the treatment of acute lung injury caused by various factors since its approval in 2002. Sivelestat sodium hydrate also improves post-traumatic knee osteoarthritis (KOA), although its underlying mechanisms of action have yet to be elucidated. The aim of the current study was to determine if sivelestat sodium hydrate improves post-traumatic KOA through nuclear factor (NF)-κB in a rat model. Treatment with sivelestat sodium hydrate significantly inhibited the induction of structural changes and significantly increased the vertical episode count and ipsilateral static weight bearing of the joint in KOA rats (all P<0.01). Sivelestat sodium hydrate significantly inhibited tumor necrosis factor-α and interleukin-6 production, serum nitrite levels, inducible nitric oxide synthase protein expression and high mobility group box 1 (HMGB1) secretion in KOA rats compared with the model group (all P<0.01). Sivelestat sodium hydrate also significantly suppressed p50/p65 DNA binding activity and NF-κB and phosphorylated inhibitor of κB protein expression in the joints of KOA rats compared with the model group (all P<0.01). These results suggest that sivelestat sodium hydrate improves post-traumatic KOA through HMGB1 and NF-κB in rats.

Sivelestat sodium hydrate improves post-traumatic knee osteoarthritis through nuclear factor-κB in a rat model

PubMed Central

Yu, Xiaofeng; Zhao, Lijun; Yu, Zhiping; Yu, Changzheng; Bi, Jianfei; Sun, Binglong; Cong, Haibo

2017-01-01

As a specific inhibitor of neutrophil elastase, sivelestat sodium hydrate has primarily been used in the treatment of acute lung injury caused by various factors since its approval in 2002. Sivelestat sodium hydrate also improves post-traumatic knee osteoarthritis (KOA), although its underlying mechanisms of action have yet to be elucidated. The aim of the current study was to determine if sivelestat sodium hydrate improves post-traumatic KOA through nuclear factor (NF)-κB in a rat model. Treatment with sivelestat sodium hydrate significantly inhibited the induction of structural changes and significantly increased the vertical episode count and ipsilateral static weight bearing of the joint in KOA rats (all P<0.01). Sivelestat sodium hydrate significantly inhibited tumor necrosis factor-α and interleukin-6 production, serum nitrite levels, inducible nitric oxide synthase protein expression and high mobility group box 1 (HMGB1) secretion in KOA rats compared with the model group (all P<0.01). Sivelestat sodium hydrate also significantly suppressed p50/p65 DNA binding activity and NF-κB and phosphorylated inhibitor of κB protein expression in the joints of KOA rats compared with the model group (all P<0.01). These results suggest that sivelestat sodium hydrate improves post-traumatic KOA through HMGB1 and NF-κB in rats. PMID:28810618

Carbon-Confined SnO2-Electrodeposited Porous Carbon Nanofiber Composite as High-Capacity Sodium-Ion Battery Anode Material.

PubMed

Dirican, Mahmut; Lu, Yao; Ge, Yeqian; Yildiz, Ozkan; Zhang, Xiangwu

2015-08-26

Sodium resources are inexpensive and abundant, and hence, sodium-ion batteries are promising alternative to lithium-ion batteries. However, lower energy density and poor cycling stability of current sodium-ion batteries prevent their practical implementation for future smart power grid and stationary storage applications. Tin oxides (SnO2) can be potentially used as a high-capacity anode material for future sodium-ion batteries, and they have the advantages of high sodium storage capacity, high abundance, and low toxicity. However, SnO2-based anodes still cannot be used in practical sodium-ion batteries because they experience large volume changes during repetitive charge and discharge cycles. Such large volume changes lead to severe pulverization of the active material and loss of electrical contact between the SnO2 and carbon conductor, which in turn result in rapid capacity loss during cycling. Here, we introduce a new amorphous carbon-coated SnO2-electrodeposited porous carbon nanofiber (PCNF@SnO2@C) composite that not only has high sodium storage capability, but also maintains its structural integrity while ongoing repetitive cycles. Electrochemical results revealed that this SnO2-containing nanofiber composite anode had excellent electrochemical performance including high-capacity (374 mAh g(-1)), good capacity retention (82.7%), and large Coulombic efficiency (98.9% after 100th cycle).

Diagnosing the pathophysiologic mechanisms of nocturnal polyuria.

PubMed

Goessaert, An-Sofie; Krott, Louise; Hoebeke, Piet; Vande Walle, Johan; Everaert, Karel

2015-02-01

Diagnosis of nocturnal polyuria (NP) is based on a bladder diary. Addition of a renal function profile (RFP) for analysis of concentrating and solute-conserving capacity allows differentiation of NP pathophysiology and could facilitate individualized treatment. To map circadian rhythms of water and solute diuresis by comparing participants with and without NP. This prospective observational study was carried out in Ghent University Hospital between 2011 and 2013. Participants with and without NP completed a 72-h bladder dairy. RFP, free water clearance (FWC), and creatinine, solute, sodium, and urea clearance were measured for all participants. The study participants were divided into those with (n=77) and those without (n=35) NP. The mean age was 57 yr (SD 16 yr) and 41% of the participants were female. Compared to participants without NP, the NP group exhibited a higher diuresis rate throughout the night (p=0.015); higher FWC (p=0.013) and lower osmolality (p=0.030) at the start of the night; and persistently higher sodium clearance during the night (p<0.001). The pathophysiologic mechanism of NP was identified as water diuresis alone in 22%, sodium diuresis alone in 19%, and a combination of water and sodium diuresis in 47% of the NP group. RFP measurement in first-line NP screening to discriminate between water and solute diuresis as pathophysiologic mechanisms complements the bladder diary and could facilitate optimal individualized treatment of patients with NP. We evaluated eight urine samples collected over 24h to detect the underlying problem in NP. We found that NP can be attributed to water or sodium diuresis or a combination of both. This urinalysis can be used to adapt treatment according to the underlying mechanism in patients with bothersome consequences of NP, such as nocturia and urinary incontinence. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Innovative technologies on fuel assemblies cleaning for sodium fast reactors: First considerations on cleaning process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simon, N.; Lorcet, H.; Beauchamp, F.

2012-07-01

Within the framework of Sodium Fast Reactor development, innovative fuel assembly cleaning operations are investigated to meet the GEN IV goals of safety and of process development. One of the challenges is to mitigate the Sodium Water Reaction currently used in these processes. The potential applications of aqueous solutions of mineral salts (including the possibility of using redox chemical reactions) to mitigate the Sodium Water Reaction are considered in a first part and a new experimental bench, dedicated to this study, is described. Anhydrous alternative options based on Na/CO{sub 2} interaction are also presented. Then, in a second part, amore » functional study conducted on the cleaning pit is proposed. Based on experimental feedback, some calculations are carried out to estimate the sodium inventory on the fuel elements, and physical methods like hot inert gas sweeping to reduce this inventory are also presented. Finally, the implementation of these innovative solutions in cleaning pits is studied in regard to the expected performances. (authors)« less

Summary of the Madison Dynamo Experiment

NASA Astrophysics Data System (ADS)

Kendrick, R. D.; Spence, E. J.; Nornberg, M. D.; Forest, C. B.

2001-10-01

A spherical dynamo experiment has been constructed at the University of Wisconsin's liquid sodium facility. The goals of the experiment are to observe and understand magnetic instabilities driven by flow shear in MHD systems, investigate MHD turbulence for magnetic Reynolds numbers of ~100, and understand the role of fluid turbulence in current generation. Magnetic field generation is possible for only specific flow geometries. We have studied and achieved simple roll flow geometries in a full scale water experiment. Results from this experiment have guided the design of the sodium experiment. The experiment consists of a 1 m diameter, spherical stainless steel vessel filled with liquid sodium at 110 Celsius. Two 100 Hp motors with impellers drive flows in the liquid sodium with flow velocities ~ 15 m/s. A gaussian grid of Hall probes on the surface of the sodium vessel measure the generated external magnetic field. Hall probe feed-thru arrays measure the internal field. Preliminary investigations include measurements of the turbulent electromotive force and excitation of magnetic eigenmodes.

Design of the Madison Dynamo Experiment

NASA Astrophysics Data System (ADS)

Kendrick, R. D.; Bayliss, R. A.; Forest, C. B.; Nornberg, M. D.; O'Connell, R.; Spence, E. J.

2003-10-01

A spherical dynamo experiment has been constructed at the University of Wisconsin's liquid sodium facility. The goals of the experiment are to observe and understand magnetic instabilities driven by flow shear in MHD systems, investigate MHD turbulence for magnetic Reynolds numbers of ˜100, and understand the role of fluid turbulence in current generation. Magnetic field generation is possible for only specific flow geometries. We have studied and achieved simple roll flow geometries in a full scale water experiment. Results from this experiment have guided the design of the sodium experiment. The experiment consists of a 1 m diameter, spherical stainless steel vessel filled with liquid sodium at 110 Celsius. Two 100 Hp motors with impellers drive flows in the liquid sodium with flow velocities ˜ 15 m/s. A grid of Hall probes on the surface of the sodium vessel measure the generated external magnetic field. Hall probe feed-thru arrays measure the internal field. Preliminary investigations include measurements of the turbulent electromotive force and excitation of magnetic eigenmodes.

Controlling Blown Pack Spoilage Using Anti-Microbial Packaging

PubMed Central

Reid, Rachael; Tyuftin, Andrey A.; Kerry, Joe P.; Whyte, Paul; Bolton, Declan

2017-01-01

Active (anti-microbial) packaging was prepared using three different formulations; Auranta FV; Inbac-MDA and sodium octanoate at two concentrations (2.5 and 3.5 times their minimum inhibitory concentration (MIC, the lowest concentration that will inhibit the visible growth of the organisms) against Clostridium estertheticum, DSMZ 8809). Inoculated beef samples were packaged using the active packaging and monitored for 100 days storage at 2 °C for blown pack spoilage. The time to the onset of blown pack spoilage was significantly (p < 0.01) increased using Auranta FV and sodium octanoate (caprylic acid sodium salt) at both concentrations. Moreover, sodium octanoate packs had significantly (p < 0.01) delayed blown pack spoilage as compared to Auranta FV. It was therefore concluded that Auranta FV or sodium octanoate, incorporated into the packaging materials used for vacuum packaged beef, would inhibit blown pack spoilage and in the case of the latter, well beyond the 42 days storage period currently required for beef primals. PMID:28805679

Controlling Blown Pack Spoilage Using Anti-Microbial Packaging.

PubMed

Reid, Rachael; Bolton, Declan; Tiuftin, Andrey A; Kerry, Joe P; Fanning, Séamus; Whyte, Paul

2017-08-12

Active (anti-microbial) packaging was prepared using three different formulations; Auranta FV; Inbac-MDA and sodium octanoate at two concentrations (2.5 and 3.5 times their minimum inhibitory concentration (MIC, the lowest concentration that will inhibit the visible growth of the organisms) against Clostridium estertheticum , DSMZ 8809). Inoculated beef samples were packaged using the active packaging and monitored for 100 days storage at 2 °C for blown pack spoilage. The time to the onset of blown pack spoilage was significantly ( p < 0.01) increased using Auranta FV and sodium octanoate (caprylic acid sodium salt) at both concentrations. Moreover, sodium octanoate packs had significantly ( p < 0.01) delayed blown pack spoilage as compared to Auranta FV. It was therefore concluded that Auranta FV or sodium octanoate, incorporated into the packaging materials used for vacuum packaged beef, would inhibit blown pack spoilage and in the case of the latter, well beyond the 42 days storage period currently required for beef primals.

Compressed sodium chloride as a fast-acting antimicrobial surface: results of a pilot study.

PubMed

Whitlock, B D; Smith, S W

2016-10-01

Antimicrobial surfaces are currently being studied as an aid to reduce transmission of pathogens leading to healthcare-associated infections (HAIs). Among the most harmful and costly pathogens that cause HAIs is meticillin-resistant Staphylococcus aureus (MRSA). Currently available and previously investigated antimicrobial surface technologies that are effective against MRSA (e.g. copper alloy surfaces) take 30min to several hours to achieve significant reduction. This article presents a new antimicrobial surface technology made of compressed sodium chloride that reduces MRSA 20-30 times faster than copper alloy surfaces. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Abnormal Ion Permeation through Cystic Fibrosis Respiratory Epithelium

NASA Astrophysics Data System (ADS)

Knowles, M. R.; Stutts, M. J.; Spock, A.; Fischer, N.; Gatzy, J. T.; Boucher, R. C.

1983-09-01

The epithelium of nasal tissue excised from subjects with cystic fibrosis exhibited higher voltage and lower conductance than tissue from control subjects. Basal sodium ion absorption by cystic fibrosis and normal nasal epithelia equaled the short-circuit current and was amiloride-sensitive. Amiloride induced chloride ion secretion in normal but not cystic fibrosis tissue and consequently was more effective in inhibiting the short-circuit current in cystic fibrosis epithelia. Chloride ion-free solution induced a smaller hyperpolarization of cystic fibrosis tissue. The increased voltage and amiloride efficacy in cystic fibrosis reflect absorption of sodium ions across an epithelium that is relatively impermeable to chloride ions.

Experiments on Turbulent Modifications to Ohm's Law in the Madison Dynamo Experiment

NASA Astrophysics Data System (ADS)

Goldwin, J.; O'Connell, R.; Kendrick, R.; Bastian, N.; Forest, C. B.

1998-11-01

Theories of MHD turbulence predict the existence of an anomalous resistivity and field-aligned current generation: j = β nabla × B + α B. The dynamo experiment being built at the University of Wisconsin-Madison is well suited for quantifying the turbulent transport coefficients α and β. The experiment is a spherical volume of liquid sodium with helical flows driven by propellers and high Reynolds number (Re ≈ 10^7), making it well suited for these studies. Two experiments are proposed: (1) A Helmholtz coil will produce a magnetic field in the z-direction, and the resulting toroidal field will be measured for the anomalous resistivity-the β-effect and (2) A toroidal magnetic field will be applied to the sphere through currents in a center column, and the induced toroidal current will be measured with a Rogowski coil-the α-effect. Complete measurements of turbulent velocity fields (including the turbulent helicity density) are being made in a dimensionally similar water experiment (water and sodium have the same viscosity and mass density) such that the magnitude of the α and β values can be estimated for the sodium experiment.

A persistent-mode 0.5 T solid-nitrogen-cooled MgB2 magnet for MRI.

PubMed

Ling, Jiayin; Voccio, John P; Hahn, Seungyong; Qu, Timing; Bascuñán, Juan; Iwasa, Yukikazu

2017-02-01

This paper presents construction details and test results of a persistent-mode 0.5-T MgB 2 magnet developed at the Francis Bitter Magnet Lab, MIT. The magnet, of 276-mm inner diameter and 290-mm outer diameter, consisted of a stack of 8 solenoidal coils with a total height of 460 mm. Each coil was wound with monofilament MgB 2 wire, equipped with a persistent-current switch and terminated with a superconducting joint, forming an individual superconducting loop. Resistive solder joints connected the 8 coils in series. The magnet, after being integrated into a testing system, immersed in solid nitrogen, was operated in a temperature range of 10-13 K. A two-stage cryocooler was deployed to cool a radiation shield and the cold mass that included mainly ~60 kg of solid nitrogen and the magnet. The solid nitrogen was capable of providing a uniform and stable cryogenic environment to the magnet. The magnet sustained a 0.47-T magnetic field at its center persistently in a range of 10-13 K. The current in each coil was inversely calculated from the measured field profile to determine the performance of each coil in persistent-mode operation. Persistent-current switches were successfully operated in solid nitrogen for ramping the magnet. They were also designed to absorb magnetic energy in a protection mechanism; its effectiveness was evaluated in an induced quench.

Development of a model describing the inhibitory effect of selected preservatives on the growth of Listeria monocytogenes in a meat model system.

PubMed

Dussault, Dominic; Vu, Khanh Dang; Lacroix, Monique

2016-02-01

The objective of this study was to evaluate the impact of seven independent factors consisting of sodium nitrite, pH, sodium chloride, sodium acetate, sodium lactate syrup, calcium propionate and a blend of nisin and hop alpha acids on the growth rate of Listeria monocytogenes in ham as a model of ready-to-eat (RTE) meat products. A central composite consisted of seven factors mentioned above was designed and the response surface methodology was applied for creating a mathematic model to predict the growth rate of L. monocytogenes in RTE meat products. Six parameters showed a significant (P ≤ 0.1) influence on the growth rate of L. monocytogenes. Only the blend of nisin and hop alpha acids did not show any significant effect (P > 0.1) in the concentrations used in this study. Increasing concentration of sodium chloride, sodium nitrite, sodium acetate, potassium lactate and calcium propionate in meat reduced bacterial growth rate while increasing pH in meat increased the growth rate of L. monocytogenes. The current mathematical equation will be an important tool in order to reduce the required number of challenge studies performed in order to ensure a safe food product. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sodium intake reduction efforts in Lebanon

PubMed Central

Almedawar, Mohamad M.; Nasreddine, Lara; Olabi, Ammar; Hamade, Haya; Awad, Elie; Toufeili, Imad; Arnaout, Samir

2015-01-01

Sodium intake reduction efforts in Lebanon are quite recent and have just started to take effect on the national level. Starting out from an academic institution, the Lebanese Action on Sodium and Health (LASH) campaign was established to counter the increasing prevalence of hypertension and associated adverse health effects. The campaign’s strategy was based on four pillars: research, health communication, advocacy, and monitoring. The LASH group set out with determining: baseline sodium intake of the population, main sources of sodium intake, and the knowledge, attitudes, and behaviors (KAB) of the population as a situation analysis that prompts for action. This gave LASH tangible evidence of the magnitude of the problem and the need for the government, the food industry, and the consumers, to be mobilized to take part in devising a solution. Currently, Lebanon is at a stage of technically working to reduce the sodium content in the major sources of sodium, namely local bread and bread-like products. The next steps will include implementation of a plan for monitoring industry compliance, while studying other food targets, including dairy products and processed meat. Meanwhile, the health communication plan is ongoing and the Salt Awareness Week is celebrated every year with media appearances of LASH researchers to raise the issue to the public eye. PMID:26090328

Dietary Sodium and Other Nutrient Intakes among Patients Undergoing Hemodialysis in New Zealand.

PubMed

Xie, Zhengxiu; McLean, Rachael; Marshall, Mark

2018-04-18

This study describes baseline intakes of sodium and other nutrients in a multi-ethnic sample of hemodialysis patients in New Zealand participating in the SoLID Trial between May/2013 to May/2016. Baseline 3-day weighed food record collections were analyzed using Foodworks 8 Professional food composition database, supplemented by other sources of nutrient information. Intakes of dietary sodium and other nutrients were compared with relevant guidelines and clinical recommendations. Eighty-five participants completed a 3-day weighed food record. The mean (SD) sodium intake was 2502 (957) mg/day at and more than half of the participants exceeded recommended intake levels. Sodium intake was positively associated with energy intake. Only 5% of participants met the recommended calorie density; nine percent of participants ate the recommended minimum of 1.2 g/kg of protein per day; 68% of participants were consuming inadequate fiber at baseline. A high proportion of dialysis patients in SoLID Trial did not meet current renal-specific dietary recommendations. The data show excess sodium intake. It is also evident that there was poor adherence to dietary guidelines for a range of other nutrients. A total diet approach is needed to lower sodium intake and improve total diet quality among hemodialysis patients in New Zealand.

Dietary Sodium and Other Nutrient Intakes among Patients Undergoing Hemodialysis in New Zealand

PubMed Central

Xie, Zhengxiu; Marshall, Mark

2018-01-01

This study describes baseline intakes of sodium and other nutrients in a multi-ethnic sample of hemodialysis patients in New Zealand participating in the SoLID Trial between May/2013 to May/2016. Baseline 3-day weighed food record collections were analyzed using Foodworks 8 Professional food composition database, supplemented by other sources of nutrient information. Intakes of dietary sodium and other nutrients were compared with relevant guidelines and clinical recommendations. Eighty-five participants completed a 3-day weighed food record. The mean (SD) sodium intake was 2502 (957) mg/day at and more than half of the participants exceeded recommended intake levels. Sodium intake was positively associated with energy intake. Only 5% of participants met the recommended calorie density; nine percent of participants ate the recommended minimum of 1.2 g/kg of protein per day; 68% of participants were consuming inadequate fiber at baseline. A high proportion of dialysis patients in SoLID Trial did not meet current renal-specific dietary recommendations. The data show excess sodium intake. It is also evident that there was poor adherence to dietary guidelines for a range of other nutrients. A total diet approach is needed to lower sodium intake and improve total diet quality among hemodialysis patients in New Zealand. PMID:29670030

Investigations of dc electrical discharges in low-pressure sodium vapor with implications for AMTEC converters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barkan, A.; Hunt, T.K.

1998-07-01

Upcoming designs for AMTEC modules capable of delivering as much as 150 watts will see the introduction of higher voltages into sodium vapor at pressures spanning a wide range. In theory, with any value for two out of three parameters: voltage, pressure, and electrode geometry, a value exists for the third parameter where DC electrical breakdown can occur; due to its low ionization energy, sodium vapor may be particularly susceptible to breakdown. This destructive event is not desirable in AMTEC modules, and sets a limit on the maximum voltage that can be built-up within any single enclosed module. An experimentalmore » cell was fabricated with representative electrode configurations and a separately heated sodium reservoir to test conditions typically expected during start-up, operation, and shutdown of AMTEC cells. Breakdown voltages were investigated in both sodium vapor and, for comparison, argon gas. The dependence on electrode material and polarity was also investigated. Additional information about leakage currents and the insulating properties of {alpha}-alumina in the presence of sodium vapor was collected, revealing a reversible tendency for conductive sodium films to build up under certain conditions, electrically shorting-out previously isolated components. In conclusion, safe operating limits on voltages, temperatures, and pressures are discussed.« less

Comparison of Cross Flow Filtration Performance for Manganese Oxide/Sludge Mixtures and Monosodium Titanate/Sludge Mixtures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poirier, M.R.

2002-06-07

Personnel performed engineering-scale tests at the Filtration Research Engineering Demonstration (FRED) to determine crossflow filter performance with a 5.6 M sodium solution containing varying concentrations of sludge and sodium permanganate. The work represents another in a series of collaborative efforts between the University of South Carolina and the Savannah River Technology Center in support of the process development efforts for the Savannah River Site. The current tests investigated filter performance with slurry containing simulated Tank 40H Sludge and sodium permanganate at concentrations between 0.070 weight percent and 3.04 weight percent insoluble solids.

Dense proton injection into phosphate glasses using corona discharge treatment

NASA Astrophysics Data System (ADS)

Kinoshita, Takuya; Miyazaki, Atsushi; Kawaguchi, Keiga; Sakai, Daisuke; Yamaguchi, Takuya; Omata, Takahisa; Ishiyama, Tomohiro; Fujioka, Masaya; Kaiju, Hideo; Nishii, Junji

2018-01-01

Sodium ions in 25NaO1/2-6LaO3/2-6GeO2-63PO5/2 (mol%) glasses were substituted with protons using corona discharge treatment (CDT) under a H2 atmosphere. The substitution of sodium ion to proton proceeded from the anode side to the cathode side with constant current flow during the CDT. A crystalline free and transparent glass plate of 0.3 mm thickness was obtained after CDT for 96 h. The maximum decrease rate from sodium ion to proton was 78 ± 10%. The proton conductivity of 8.5 × 10-4 S/cm was attained at 400 °C.

Salt taste adaptation: the psychophysical effects of adapting solutions and residual stimuli from prior tastings on the taste of sodium chloride.

PubMed

O'Mahony, M

1979-01-01

The paper reviews how adaptation to sodium chloride, changing in concentration as a result of various experimental procedures, affects measurements of the sensitivity, intensity, and quality of the salt taste. The development of and evidence for the current model that the salt taste depends on an adaptation level (taste zero) determined by the sodium cation concentration is examined and found to be generally supported, despite great methodological complications. It would seem that lower adaptation levels elicit lower thresholds, higher intensity estimates, and altered quality descriptions with predictable effects on psychophysical measures.

Eradication of Pseudomonas aeruginosa cells by cathodic electrochemical currents delivered with graphite electrodes.

PubMed

Niepa, Tagbo H R; Wang, Hao; Gilbert, Jeremy L; Ren, Dacheng

2017-03-01

Antibiotic resistance is a major challenge to the treatment of bacterial infections associated with medical devices and biomaterials. One important intrinsic mechanism of such resistance is the formation of persister cells that are phenotypic variants of microorganisms and highly tolerant to antibiotics. Recently, we reported a new approach to eradicating persister cells of Pseudomonas aeruginosa using low-level direct electrochemical current (DC) and synergy with the antibiotic tobramycin. To further understand the underlying mechanism and develop this technology toward possible medical applications, we investigated the electricidal activities of non-metallic biomaterial on persister and biofilm cells of P. aeruginosa using graphite-based TGON™ 805 electrodes. We employed both single and dual chamber systems to compare electrochemical factors of TGON and stainless steel 304 electrodes. The results revealed that TGON-based treatments were highly effective against P. aeruginosa persister cells. In the single chamber system, complete eradication of planktonic persister cells (corresponding to a 7-log killing) was achieved with 70μA/cm 2 DC using TGON electrodes within 40min of treatment, while the cell viability in biofilms was reduced by 2 logs within 1h. The killing effects were dose and time dependent with higher current densities requiring less time. Moreover, reduction reactions were found more effective than oxidation reactions, confirming that metal cations are not indispensable, although they may facilitate cell killing. The findings of this study can help develop electrochemical technologies to eradicate persister and biofilm cells for more effective treatment of medical device and biomaterial associated infections. Infections associated with medical devices and biomaterials present a major challenge due to high-level tolerance of microbes to conventional antibiotics. It is well established that such tolerance is due to the formation of dormant persister cells and multicellular structures known as biofilms. Recent studies have demonstrated electrochemical treatment as a promising alternative to eradicate bacterial infections, since the killing mechanism is independent of the growth phase of bacterial cells, but relies on various electrochemical species interplaying during the treatment. The current study investigated major bactericidal properties of the electrochemical currents mediated via TGON, a carbon-based electrode material. Up to total eradication of Pseudomonas aeruginosa persister cells was achieved. The new knowledge of electrochemical properties and the bioactivity of TGON may help develop new methods/devices to eradicate bacterial infections by delivering safe levels of electrochemical currents. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Sodium valproate induced gingival enlargement with pre-existing chronic periodontitis.

PubMed

Joshipura, Vaibhavi

2012-04-01

Gingival enlargement is a common clinical feature of gingival and periodontal diseases. Currently, more than 20 prescription medications are associated with gingival enlargement. Although the mechanisms of action may be different, the clinical and microscopic appearance of drug-induced gingival enlargement is similar with any drug. Gingival enlargement produces esthetic changes, and clinical symptoms including pain, tenderness, bleeding, speech disturbances, abnormal tooth movement, dental occlusion problems, enhancement of caries development and periodontal disorders. Sodium valproate is considered to produce gingival enlargement, but very rarely. This case report features sodium valproate induced gingival enlargement in a patient with pre-existing chronic periodontitis, who came to the Dental Department, Chinmaya Mission Hospital, Bangalore. The case is special as the patient did not develop the enlargement in spite of taking phenytoin for 1 year and developed enlargement with sodium valproate within 6 months.

Molecular Mechanism of Action and Selectivity of Sodium Channel Blocker Insecticides

PubMed Central

Silver, Kristopher; Dong, Ke; Zhorov, Boris S.

2017-01-01

Sodium channel blocker insecticides (SCBIs) are a relatively new class of insecticides that are represented by two commercially registered compounds, indoxacarb and metaflumizone. SCBIs, like pyrethroids and DDT, target voltage-gated sodium channels (VGSCs) to intoxicate insects. In contrast to pyrethroids, however, SCBIs inhibit VGSCs at a distinct receptor site that overlaps those of therapeutic inhibitors of sodium channels, such as local anesthetics, anticonvulsants and antiarrhythmics. This review will recount the development of the SCBI insecticide class from its roots as chitin synthesis inhibitors, discuss the symptoms of poisoning and evidence supporting inhibition of VGSCs as their mechanism of action, describe the current model for SCBI-induced inhibition of VGSCs, present a model for the receptor for SCBIs on VGSCs, and highlight differences between data collected from mammalian and insect experimental models. PMID:27993108

Ultrathin molybdenum diselenide nanosheets anchored on multi-walled carbon nanotubes as anode composites for high performance sodium-ion batteries

NASA Astrophysics Data System (ADS)

Zhang, Zhian; Yang, Xing; Fu, Yun; Du, Ke

2015-11-01

Ultrathin molybdenum diselenide nanosheets are decorated on the surface of multi-walled carbon nanotubes (MWCNT) via a one-step hydrothermal method. Uniform MoSe2 nanosheets are firmly anchored on MWCNT according to the characterizations of scanning electron microscope (SEM), transmission electron microscope (TEM). When evaluated as anodes for sodium storage, the MoSe2@MWCNT composites deliver a reversible specific capacity of 459 mAh g-1 at a current of 200 mA g-1 over 90 cycles, and a specific capacity of 385 mAh g-1 even at a current rate of 2000 mAh g-1, which is better than the MoSe2 nanosheets. The enhanced electrochemical performance of the MoSe2@MWCNT composites can be ascribed to the synergic effects of MoSe2 nanosheets and MWCNT. The high capacity and good rate performance reveal that the MoSe2@MWCNT composites are very promising for applications in sodium-ion batteries.

Gender Role Conflict, Professional Role Confidence, and Intentional Persistence in Engineering Students in China

ERIC Educational Resources Information Center

Yang, Xueyan; Wang, Xinhong; Zhang, Lin; Weidman, John C.

2017-01-01

In the current study, the relationship between gender role conflict, professional role confidence, and intentional persistence was examined using data from a survey of male and female Chinese engineering students. Intentional persistence was significantly associated with gender role conflict and professional role confidence; however, the pattern…

Neural Indices of Semantic Processing in Early Childhood Distinguish Eventual Stuttering Persistence and Recovery

ERIC Educational Resources Information Center

Kreidler, Kathryn; Wray, Amanda Hampton; Usler, Evan; Weber, Christine

2017-01-01

Purpose: Maturation of neural processes for language may lag in some children who stutter (CWS), and event-related potentials (ERPs) distinguish CWS who have recovered from those who have persisted. The current study explores whether ERPs indexing semantic processing may distinguish children who will eventually persist in stuttering…

Perioperative Management of Severe Hypertension during Laparoscopic Surgery for Pheochromocytoma

PubMed Central

Erdoğan, Mehmet Ali; Uçar, Muharrem; Özkan, Ahmet Selim; Özgül, Ülkü; Durmuş, Mahmut

2016-01-01

Phaeochromocytoma is a catecholamine-secreting vascular tumour that is derived from chromaffin cell. Lethal cardiovascular complications, such as serious hypertension, myocardial infarction and aortic dissection, may occur because of uncontrolled catecholamine release. Each stage of anaesthesia management has vital importance because of this destructive catecholamine secretion that may occur during induction, perioperative stage and surgical manipulation. In this study, we report regarding the preoperative preparation and severe, persistent hypertension attack management with a combination of α-adrenergic blockade, β-adrenergic blockade, sodium nitroprusside and remifentanil in a patient who underwent laparoscopic surgery for phaeochromocytoma. PMID:27366556

Experimental evidence for two thermodynamic length scales in neutralized polyacrylate gels

NASA Astrophysics Data System (ADS)

Horkay, Ferenc; Hecht, Anne-Marie; Grillo, Isabelle; Basser, Peter J.; Geissler, Erik

2002-11-01

The small angle neutron scattering (SANS) behavior of fully neutralized sodium polyacrylate gels is investigated in the presence of calcium ions. Analysis of the SANS response reveals the existence of three characteristic length scales, two of which are of thermodynamic origin, while the third length is associated with the frozen-in structural inhomogeneities. This latter contribution exhibits power law behavior with a slope of about -3.6, reflecting the presence of interfaces. The osmotically active component of the scattering signal is defined by two characteristic length scales, a correlation length ξ and a persistence length L.

It Is Chloride Depletion Alkalosis, Not Contraction Alkalosis

PubMed Central

Galla, John H.

2012-01-01

Maintenance of metabolic alkalosis generated by chloride depletion is often attributed to volume contraction. In balance and clearance studies in rats and humans, we showed that chloride repletion in the face of persisting alkali loading, volume contraction, and potassium and sodium depletion completely corrects alkalosis by a renal mechanism. Nephron segment studies strongly suggest the corrective response is orchestrated in the collecting duct, which has several transporters integral to acid-base regulation, the most important of which is pendrin, a luminal Cl/HCO3− exchanger. Chloride depletion alkalosis should replace the notion of contraction alkalosis. PMID:22223876

Ethanol and sodium acetate as a preservation method to delay degradation of environmental DNA

USGS Publications Warehouse

Ladell, Bridget A.; Walleser, Liza R.; McCalla, S. Grace; Erickson, Richard A.; Amberg, Jon J.

2018-01-01

Environmental DNA (eDNA) samples that are collected from remote locations depend on rapid stabilization of the DNA. The degradation of eDNA in water samples is minimized when samples are stored at ≤ 4 °C. Developing a preservation technique to maintain eDNA integrity at room temperature would allow a wider range of locations to be sampled. We evaluated an ethanol and sodium acetate solution to maintain the integrity of the DNA samples for the time between collection and lab testing. For this evaluation, replicate water samples taken from a tank housing Asian carp were placed on ice or held at room temperature. At both temperatures, water samples were left untreated or were preserved with an ethanol and sodium acetate solution (EtOH–NaAc). Every day for 6 days following collection, a subset of the samples was removed from each preservation method and DNA was extracted and nuclear and mitochondrial markers were assayed with qPCR. Results showed comparable persistence of DNA between iced samples without the EtOH–NaAc treatment and samples that received EtOH–NaAc treatment that were kept at room temperature. We found that DNA can be amplified from preserved samples using an EtOH–NaAc solution after up to 7 days at room temperature.

Influence of Near-Surface Severe Plastic Deformation of Mild Steel on the Inhibition Performance of Sodium Molybdate and 1H-Benzotriazole in Artificial Sea Water

NASA Astrophysics Data System (ADS)

Sabet Bokati, Kazem; Dehghanian, Changiz; Babaei, Mahdi

2018-02-01

The effects of near-surface severe plastic deformation (NS-SPD) on the inhibition performance of sodium molybdate (SM) and 1H-benzotriazole (BTA) for mild steel were investigated using weight loss, polarization and electrochemical impedance spectroscopy measurements. The crystal grain size of NS-SPD-processed surface was analyzed by x-ray diffractometry and field emission scanning electron microscopy. A deformed layer with thickness of 20 ± 5 µm was produced on mild steel surface after NS-SPD process due to accumulated strains. The NS-SPD process caused more effective adsorption of corrosion inhibitors due to the fabrication of a surface with a high density of preferential adsorption sites. However, the stability of protective layer was predominantly influenced by the effect of NS-SPD process on inhibition efficiency. The fairly good persistence of protective layer formed on the surface by SM-containing solution and also positive effect of NS-SPD process on adsorption of molybdate ions caused higher inhibition performance for sodium molybdate. However, NS-SPD process encouraged deterioration of protective layer formed on steel surface in the presence of BTA inhibitor. It was ascribed to partial coverage of surface, low stability of adsorbed layer and thus more adsorption of aggressive ions on unprotected area which was uncovered during immersion time.

Dynamic domains of the Derviche Tourneur sodium experiment: Simulations of a spherical magnetized Couette flow

NASA Astrophysics Data System (ADS)

Kaplan, E. J.; Nataf, H.-C.; Schaeffer, N.

2018-03-01

The Derviche Tourneur sodium experiment, a spherical Couette magnetohydrodynamics experiment with liquid sodium as the medium and a dipole magnetic field imposed from the inner sphere, recently underwent upgrades to its diagnostics to better characterize the flow and induced magnetic fields with global rotation. In tandem with the upgrades, a set of direct numerical simulations were run to give a more complete view of the fluid and magnetic dynamics at various rotation rates of the inner and outer spheres. These simulations reveal several dynamic regimes, determined by the Rossby number. At positive differential rotation there is a regime of quasigeostrophic flow, with low levels of fluctuations near the outer sphere. Negative differential rotation shows a regime of what appear to be saturated hydrodynamic instabilities at low negative differential rotation, followed by a regime where filamentary structures develop at low latitudes and persist over five to ten differential rotation periods as they drift poleward. We emphasize that all these coherent structures emerge from turbulent flows. At least some of them seem to be related to linear instabilities of the mean flow. The simulated flows can produce the same measurements as those that the physical experiment can take, with signatures akin to those found in the experiment. This paper discusses the relation between the internal velocity structures of the flow and their magnetic signatures at the surface.

Acute and chronic respiratory effects of sodium borate particulate exposures.

PubMed Central

Wegman, D H; Eisen, E A; Hu, X; Woskie, S R; Smith, R G; Garabrant, D H

1994-01-01

This study examined work-related chronic abnormality in pulmonary function and work-related acute irritant symptoms associated with exposure to borate dust in mining and processing operations. Chronic effects were examined by pulmonary function at the beginning and end of a 7-year interval. Time-specific estimates of sodium borate particulate exposures were used to estimate cumulative exposure during the study interval. Change in pulmonary function over the 7 years was found unrelated to the estimate of cumulative exposure during that interval. Exposure-response associations also were examined with respect to short-term peak exposures and incidence of five symptoms of acute respiratory irritation. Hourly measures of health outcome and continuous measures of particulate exposure were made on each subject throughout the day. Whenever a subject reported one of the irritant symptoms, a symptom intensity score was also recorded along with the approximate time of onset. The findings indicated that exposure-response relationships were present for each of the specific symptoms at several symptom intensity levels. The associations were present when exposure was estimated by both day-long and short-term (15-min) time-weighted average exposures. Associations persisted after taking account of smoking, age, and the presence of a common cold. No significant difference in response rate was found between workers exposed to different types of sodium borate dusts. PMID:7889871

The frequently used intraperitoneal hyponatraemia model induces hypovolaemic hyponatraemia with possible model-dependent brain sodium loss.

PubMed

Overgaard-Steensen, Christian; Stødkilde-Jørgensen, Hans; Larsson, Anders; Tønnesen, Else; Frøkiaer, Jørgen; Ring, Troels

2016-07-01

What is the central question of this study? The brain response to acute hyponatraemia is usually studied in rodents by intraperitoneal instillation of hypotonic fluids (i.p. model). The i.p. model is described as 'dilutional' and 'syndrome of inappropriate ADH (SIADH)', but the mechanism has not been explored systematically and might affect the brain response. Therefore, in vivo brain and muscle response were studied in pigs. What is the main finding and its importance? The i.p. model induces hypovolaemic hyponatraemia attributable to sodium redistribution, not dilution. A large reduction in brain sodium is observed, probably because of the specific mechanism causing the hyponatraemia. This is not accounted for in current understanding of the brain response to acute hyponatraemia. Hyponatraemia is common clinically, and if it develops rapidly, brain oedema evolves, and severe morbidity and even death may occur. Experimentally, acute hyponatraemia is most frequently studied in small animal models, in which the hyponatraemia is produced by intraperitoneal instillation of hypotonic fluids (i.p. model). This hyponatraemia model is described as 'dilutional' or 'syndrome of inappropriate ADH (SIADH)', but seminal studies contradict this interpretation. To confront this issue, we developed an i.p. model in a large animal (the pig) and studied water and electrolyte responses in brain, muscle, plasma and urine. We hypothesized that hyponatraemia was induced by simple water dilution, with no change in organ sodium content. Moderate hypotonic hyponatraemia was induced by a single i.v. dose of desmopressin and intraperitoneal instillation of 2.5% glucose. All animals were anaesthetized and intensively monitored. In vivo brain and muscle water was determined by magnetic resonance imaging and related to the plasma sodium concentration. Muscle water content increased less than expected as a result of pure dilution, and muscle sodium content decreased significantly (by 28%). Sodium was redistributed to the peritoneal fluid, resulting in a significantly reduced plasma volume. This shows that the i.p. model induces hypovolaemic hyponatraemia and not dilutional/SIADH hyponatraemia. Brain oedema evolved, but brain sodium content decreased significantly (by 21%). To conclude, the i.p. model induces hypovolaemic hyponatraemia attributable to sodium redistribution and not water dilution. The large reduction in brain sodium is probably attributable to the specific mechanism that causes the hyponatraemia. This is not accounted for in the current understanding of the brain response to acute hyponatraemia. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.

The Development and Fabrication of an Implantable, Multiplexed, Semiconductor Multielectrode Array.

DTIC Science & Technology

1983-12-01

ILt D. C. Denton . Their individual and collective efforts in designing, fabricating, and testing an implantable array resulted in a semiconductor device... contaminating sodium ions were attracted by the electrical field developed by the JFET pinch-off voltage. These sodium ions produced leakage paths...34 was implanted in a biological specimen (dog) by Hensley and Denton (Ref 5). Summary of Current Knowledge Hensley and Denton showed the feasibility

Pediatric drug formulation of sodium benzoate extended-release granules.

PubMed

Combescot, E; Morat, G; de Lonlay, P; Boudy, V

2016-01-01

Urea cycle disorders are a group of inherited orphan diseases leading to hyperammonemia. Current therapeutic strategy includes high doses of sodium benzoate leading to three or four oral intakes per day. As this drug is currently available in capsules or in solution, children are either unable to swallow the capsule or reluctant to take the drug due to its strong bitter taste. The objective of the present study was to develop solid, multiparticulate formulations of sodium benzoate, which are suitable for pediatric patients (i.e. flavor-masked, easy to swallow and with a dosing system). Drug layering and coating in a fluidized bed were applied for preparing sustained-release granules. Two types of inert cores (GalenIQ® and Suglets®) and three different polymers (Kollicoat®, Aquacoat® and Eudragit®) were tested in order to select the most appropriate polymer and starter core for our purpose. Physical characteristics and drug release profiles of the pellets were evaluated. A Suglets® core associated with a Kollicoat® coating seems to be the best combination for an extended release of sodium benzoate. A curing period of 8 h was necessary to complete film formation and the resulting drug release pattern was found to be dependent of the acidity of the release medium.

Reducing calories, fat, saturated fat and sodium in restaurant menu items: Effects on consumer acceptance

PubMed Central

Patel, Anjali A.; Lopez, Nanette V.; Lawless, Harry T.; Njike, Valentine; Beleche, Mariana; Katz, David L.

2016-01-01

OBJECTIVE This study assessed consumer acceptance of reductions of calories, fat, saturated fat, and sodium to current restaurant recipes. METHODS Twenty-four menu items, from six restaurant chains, were slightly modified and moderately modified by reducing targeted ingredients. Restaurant customers (n=1,838) were recruited for a taste test and were blinded to the recipe version as well as the purpose of the study. Overall consumer acceptance was measured using a 9-point hedonic (like/dislike) scale, likelihood to purchase scale, Just-About-Right (JAR) 5-point scale, penalty analysis and alienation analysis. RESULTS Overall, modified recipes of 19 menu items were scored similar to (or better than) their respective current versions. Eleven menu items were found to be acceptable at the slightly modified recipe version and eight menu items were found to be acceptable at the moderately modified recipe version. Acceptable ingredient reductions resulted in a reduction of up to 26% in calories and a reduction of up to 31% in sodium per serving. CONCLUSIONS The majority of restaurant menu items with small reductions of calories, fat, saturated fat and sodium were acceptable. Given the frequency of eating foods away from home, these reductions could be effective in creating dietary improvements for restaurant diners. PMID:27891828

Reducing calories, fat, saturated fat, and sodium in restaurant menu items: Effects on consumer acceptance.

PubMed

Patel, Anjali A; Lopez, Nanette V; Lawless, Harry T; Njike, Valentine; Beleche, Mariana; Katz, David L

2016-12-01

To assess consumer acceptance of reductions of calories, fat, saturated fat, and sodium to current restaurant recipes. Twenty-four menu items, from six restaurant chains, were slightly modified and moderately modified by reducing targeted ingredients. Restaurant customers (n = 1,838) were recruited for a taste test and were blinded to the recipe version as well as the purpose of the study. Overall consumer acceptance was measured using a 9-point hedonic (like/dislike) scale, likelihood to purchase scale, Just-About-Right (JAR) 5-point scale, penalty analysis, and alienation analysis. Overall, modified recipes of 19 menu items were scored similar to (or better than) their respective current versions. Eleven menu items were found to be acceptable in the slightly modified recipe version, and eight menu items were found to be acceptable in the moderately modified recipe version. Acceptable ingredient modifications resulted in a reduction of up to 26% in calories and a reduction of up to 31% in sodium per serving. The majority of restaurant menu items with small reductions of calories, fat, saturated fat, and sodium were acceptable. Given the frequency of eating foods away from home, these reductions could be effective in creating dietary improvements for restaurant diners. © 2016 The Obesity Society.

3D Interconnected Carbon Fiber Network-Enabled Ultralong Life Na3 V2 (PO4 )3 @Carbon Paper Cathode for Sodium-Ion Batteries.

PubMed

Kretschmer, Katja; Sun, Bing; Zhang, Jinqiang; Xie, Xiuqiang; Liu, Hao; Wang, Guoxiu

2017-03-01

Sodium-ion batteries (NIBs) are an emerging technology, which can meet increasing demands for large-scale energy storage. One of the most promising cathode material candidates for sodium-ion batteries is Na 3 V 2 (PO 4 ) 3 due to its high capacity, thermal stability, and sodium (Na) Superionic Conductor 3D (NASICON)-type framework. In this work, the authors have significantly improved electrochemical performance and cycling stability of Na 3 V 2 (PO 4 ) 3 by introducing a 3D interconnected conductive network in the form of carbon fiber derived from ordinary paper towel. The free-standing Na 3 V 2 (PO 4 ) 3 -carbon paper (Na 3 V 2 (PO 4 ) 3 @CP) hybrid electrodes do not require a metallic current collector, polymeric binder, or conducting additives to function as a cathode material in an NIB system. The Na 3 V 2 (PO 4 ) 3 @CP cathode demonstrates extraordinary long term cycling stability for 30 000 deep charge-discharge cycles at a current density of 2.5 mA cm -2 . Such outstanding cycling stability can meet the stringent requirements for renewable energy storage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Conduction velocity is regulated by sodium channel inactivation in unmyelinated axons innervating the rat cranial meninges.

PubMed

De Col, Roberto; Messlinger, Karl; Carr, Richard W

2008-02-15

Axonal conduction velocity varies according to the level of preceding impulse activity. In unmyelinated axons this typically results in a slowing of conduction velocity and a parallel increase in threshold. It is currently held that Na(+)-K(+)-ATPase-dependent axonal hyperpolarization is responsible for this slowing but this has long been equivocal. We therefore examined conduction velocity changes during repetitive activation of single unmyelinated axons innervating the rat cranial meninges. In direct contradiction to the currently accepted postulate, Na(+)-K(+)-ATPase blockade actually enhanced activity-induced conduction velocity slowing, while the degree of velocity slowing was curtailed in the presence of lidocaine (10-300 microm) and carbamazepine (30-500 microm) but not tetrodotoxin (TTX, 10-80 nm). This suggests that a change in the number of available sodium channels is the most prominent factor responsible for activity-induced changes in conduction velocity in unmyelinated axons. At moderate stimulus frequencies, axonal conduction velocity is determined by an interaction between residual sodium channel inactivation following each impulse and the retrieval of channels from inactivation by a concomitant Na(+)-K(+)-ATPase-mediated hyperpolarization. Since the process is primarily dependent upon sodium channel availability, tracking conduction velocity provides a means of accessing relative changes in the excitability of nociceptive neurons.

Organ allocation for chronic liver disease: model for end-stage liver disease and beyond.

PubMed

Asrani, Sumeet K; Kim, W Ray

2010-05-01

Implementation of the model for end-stage liver disease (MELD) score has led to a reduction in waiting list registration and waitlist mortality. Prognostic models have been proposed to either refine or improve the current MELD-based liver allocation. The model for end-stage liver disease - sodium (MELDNa) incorporates serum sodium and has been shown to improve the predictive accuracy of the MELD score. However, laboratory variation and manipulation of serum sodium is a concern. Organ allocation in the United Kingdom is now based on a model that includes serum sodium. An updated MELD score is associated with a lower relative weight for serum creatinine coefficient and a higher relative weight for bilirubin coefficient, although the contribution of reweighting coefficients as compared with addition of variables is unclear. The D-MELD, the arithmetic product of donor age and preoperative MELD, proposes donor-recipient matching; however, inappropriate transplantation of high-risk donors is a concern. Finally, the net benefit model ranks patients according to the net survival benefit that they would derive from the transplant. However, complex statistical models are required and unmeasured characteristics may unduly affect the model. Despite their limitations, efforts to improve the current MELD-based organ allocation are encouraging.

Sodium and calcium currents in neuroblastoma x glioma hybrid cells before and after morphological differentiation by dibutyryl cyclic AMP.

PubMed

Bodewei, R; Hering, S; Schubert, B; Wollenberger, A

1985-04-01

Sodium and calcium inward currents (INa and ICa) were measured in neuroblastoma X glioma hybrid cells of clones 108CC5 and 108CC15 by a single suction pipette method for internal perfusion and voltage clamp. Morphologically undifferentiated, exponentially growing cells were compared with cells differentiated by cultivation with 1 mmol/l dibutyryl cyclic AMP. Outward currents were eliminated by perfusing the cells with a K+-free solution. Voltage dependence and ion selectivity as well as steady state inactivation characteristics of INa and ICa resembled those of differentiated mouse neuroblastoma cells, clone N1E-115 (Moolenaar and Spector 1978, 1979). These parameters were identical in undifferentiated and differentiated cells of both clones. After differentiation the average density of the peak sodium and calcium currents was increased two and four-fold, respectively, in both cell lines. Our data indicate that exponentially growing, morphologically undifferentiated 108CC5 and 108CC15 neuroblastoma X glioma hybrid cells possess functional Na+ and Ca2+ channels undistinguishable from those of non-proliferating cells of these clones differentiated morphologically by treatment with dibutyryl cyclic AMP. That Na+ and Ca2+ spikes were not detected by other authors in these cells prior to morphological differentiation by dibutyryl cyclic AMP may be attributed to the fact that at the low resting membrane potential measured the Na+ and Ca2+ channels are inactivated.

Structures of closed and open states of a voltage-gated sodium channel

PubMed Central

Lenaeus, Michael J.; Gamal El-Din, Tamer M.; Ramanadane, Karthik; Pomès, Régis; Zheng, Ning; Catterall, William A.

2017-01-01

Bacterial voltage-gated sodium channels (BacNavs) serve as models of their vertebrate counterparts. BacNavs contain conserved voltage-sensing and pore-forming domains, but they are homotetramers of four identical subunits, rather than pseudotetramers of four homologous domains. Here, we present structures of two NaVAb mutants that capture tightly closed and open states at a resolution of 2.8–3.2 Å. Introduction of two humanizing mutations in the S6 segment (NaVAb/FY: T206F and V213Y) generates a persistently closed form of the activation gate in which the intracellular ends of the four S6 segments are drawn tightly together to block ion permeation completely. This construct also revealed the complete structure of the four-helix bundle that forms the C-terminal domain. In contrast, truncation of the C-terminal 40 residues in NavAb/1–226 captures the activation gate in an open conformation, revealing the open state of a BacNav with intact voltage sensors. Comparing these structures illustrates the full range of motion of the activation gate, from closed with its orifice fully occluded to open with an orifice of ∼10 Å. Molecular dynamics and free-energy simulations confirm designation of NaVAb/1–226 as an open state that allows permeation of hydrated Na+, and these results also support a hydrophobic gating mechanism for control of ion permeation. These two structures allow completion of a closed–open–inactivated conformational cycle in a single voltage-gated sodium channel and give insight into the structural basis for state-dependent binding of sodium channel-blocking drugs. PMID:28348242

Milan hypertensive rat as a model for studying cation transport abnormality in genetic hypertension

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferrari, P.; Barber, B.R.; Torielli, L.

1987-11-01

Environmental factors, genetic polymorphisms, and different experimental designs have been the main impediments to evaluating a genetic association between cell membrane cation transport abnormalities and human essential or genetic hypertension. We review the results obtained in the Milan hypertensive strain of rats (MHS) and in its appropriate control normotensive strain (MNS) to illustrate our approach to defining the role of cation transport abnormality in a type of genetic hypertension. Before the development of a difference in blood pressure between the two strains, the comparison of kidney and erythrocyte functions showed that MHS had an increased glomerular filtration rate and urinarymore » output, and lower plasma renin and urine osmolality. Kidney cross-transplantation between the strains showed that hypertension is transplanted with the kidney. Proximal tubular cell volume and sodium content were lower in MHS while sodium transport across the brush border membrane vesicles of MHS was faster. Erythrocytes in MHS were smaller and had lower sodium concentration, and Na+-K+ cotransport and passive permeability were faster. The differences in volume, sodium content, and Na+-K+ cotransport between erythrocytes of the two strains persisted after transplantation of bone marrow to irradiated F1 (MHS X MNS) hybrids. Moreover, in normal segregating F2 hybrid populations there was a positive correlation between blood pressure and Na+-K+ cotransport. These results suggest a genetic and functional link in MHS between cell membrane cation transport abnormalities and hypertension. Thus, erythrocyte cell membrane may be used for approaching the problem of defining the genetically determined molecular mechanism underlying the development of a type of essential hypertension. 35 references.« less

Increased Sensitivity to Angiotensin II is Present Postpartum in Women with History of Hypertensive Pregnancy

PubMed Central

Saxena, Aditi R.; Karumanchi, S. Ananth; Brown, Nancy J.; Royle, Caroline M.; McElrath, Thomas F.; Seely, Ellen W.

2010-01-01

Pregnancies complicated by new onset hypertension are associated with increased sensitivity to angiotensin II, but it is unclear if this sensitivity persists postpartum. We studied pressor response to infused angiotensin II in 25 normotensive postpartum women in both high and low sodium balance. Ten women had history of hypertensive pregnancy (five with preeclampsia; five with transient hypertension of pregnancy) and 15 women had history of uncomplicated, normotensive pregnancy. Systolic and diastolic blood pressures, aldosterone and soluble fms-like tyrosine kinase 1 (sFlt-1) levels were measured before and after angiotensin II infusion in both dietary phases. In high sodium balance, women with history of hypertensive pregnancy were normotensive but had significantly higher systolic and diastolic blood pressures than controls (115 vs. 104 mmHg and 73 vs. 65 mmHg, respectively, p<0.05). Women with history of hypertensive pregnancy had pressor response to salt loading, demonstrated by increase in systolic blood pressure on high salt diet. They also had greater systolic pressor response (10 vs. 2 mmHg, p=0.03), greater increase in aldosterone (56.8 vs. 30.8 ng/dL, p=0.03) and increase in sFlt-1 levels (11.0 vs. -18.9 pg/mL, p=0.02) after infusion of angiotensin II in low sodium balance, compared with controls. Thus, women with history of hypertensive pregnancy demonstrated salt sensitivity of blood pressure and had increased pressor, adrenal and sFlt-1 responses to infused angiotensin II in low sodium balance. Increased sensitivity to angiotensin II observed during pregnancy in women with hypertensive pregnancy is present postpartum; this feature may contribute to future cardiovascular risk in these women. PMID:20308605

Increased sensitivity to angiotensin II is present postpartum in women with a history of hypertensive pregnancy.

PubMed

Saxena, Aditi R; Karumanchi, S Ananth; Brown, Nancy J; Royle, Caroline M; McElrath, Thomas F; Seely, Ellen W

2010-05-01

Pregnancies complicated by new-onset hypertension are associated with increased sensitivity to angiotensin II, but it is unclear whether this sensitivity persists postpartum. We studied pressor response to infused angiotensin II in 25 normotensive postpartum women in both high- and low-sodium balance. Ten women had a history of hypertensive pregnancy (5 with preeclampsia; 5 with transient hypertension of pregnancy), and 15 women had a history of uncomplicated, normotensive pregnancy. Systolic and diastolic blood pressures, aldosterone, and soluble fms-like tyrosine kinase 1 levels were measured before and after angiotensin II infusion in both dietary phases. In high sodium balance, women with a history of hypertensive pregnancy were normotensive but had significantly higher systolic and diastolic blood pressures than controls (115 versus 104 mm Hg and 73 versus 65 mm Hg, respectively; P<0.05). Women with a history of hypertensive pregnancy had a pressor response to salt loading, demonstrated by an increase in systolic blood pressure on a high-salt diet. They also had greater systolic pressor response (10 versus 2 mm Hg; P=0.03), greater increase in aldosterone (56.8 versus 30.8 ng/dL; P=0.03), and increase in soluble fms-like tyrosine kinase 1 levels (11.0 versus -18.9 pg/mL; P=0.02) after infusion of angiotensin II in low-sodium balance compared with controls. Thus, women with a history of hypertensive pregnancy demonstrated salt sensitivity of blood pressure and had increased pressor, adrenal, and soluble fms-like tyrosine kinase 1 responses to infused angiotensin II in low-sodium balance. Increased sensitivity to angiotensin II observed during pregnancy in women with hypertensive pregnancy is present postpartum; this feature may contribute to future cardiovascular risk in these women.

A simple diagnostic test to confirm correct intravascular placement of peripheral catheters in order to avoid extravasation.

PubMed

Keidan, Ilan; Sidi, Avner; Ben-Menachem, Erez; Derazne, Estela; Berkenstadt, Haim

2015-11-01

Intravenous catheters are ubiquitous among modern medical management of patients, yet misplaced or tissued cannulas can result in serious iatrogenic injury due to infiltration or extravasation of injectate. Prevention is difficult, and currently few reliable tests exist to confirm intravascular placement of catheters in awake spontaneously breathing patients. Twenty conscious spontaneously breathing healthy volunteers were injected with 50 mL normal saline and 50 mL 4.2%, or 50 mL 2.1%, or 20 mL 4.2% sodium bicarbonate in a random order. A blinded anesthetist observed continuous sampling of exhaled carbon dioxide and was asked to differentiate between the sodium bicarbonate and saline injections. Peak increase in measured exhaled carbon dioxide was also calculated. Exhaled carbon dioxide increased significantly in participants injected with intravenous sodium bicarbonate. Mean peak increase was 7.4 mm Hg (±2.1 mm Hg) for 50 mL 4.2% sodium bicarbonate, 4.7 mm Hg (±2.5 mm Hg) for 20 mL 4.2% sodium bicarbonate, and 3.5 mm Hg (±1. 8 mm Hg) for 50 mL 2.1% sodium bicarbonate. The blinded observer correctly identified the injection as sodium bicarbonate or normal saline in every instance. Intravenous injection of dilute sodium bicarbonate with exhaled carbon dioxide monitoring reliably confirms correct intravascular placement of a catheter. A transient increase of exhaled carbon dioxide by 10% or more is an objective and reliable confirmation of intravascular location of the catheter. We recommend using 20 mL of 4.2% sodium bicarbonate to minimize the mEq dose of sodium bicarbonate required. Copyright © 2015 Elsevier Inc. All rights reserved.

An Assessment of Fission Product Scrubbing in Sodium Pools Following a Core Damage Event in a Sodium Cooled Fast Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bucknor, M.; Farmer, M.; Grabaskas, D.

The U.S. Nuclear Regulatory Commission has stated that mechanistic source term (MST) calculations are expected to be required as part of the advanced reactor licensing process. A recent study by Argonne National Laboratory has concluded that fission product scrubbing in sodium pools is an important aspect of an MST calculation for a sodium-cooled fast reactor (SFR). To model the phenomena associated with sodium pool scrubbing, a computational tool, developed as part of the Integral Fast Reactor (IFR) program, was utilized in an MST trial calculation. This tool was developed by applying classical theories of aerosol scrubbing to the decontamination ofmore » gases produced as a result of postulated fuel pin failures during an SFR accident scenario. The model currently considers aerosol capture by Brownian diffusion, inertial deposition, and gravitational sedimentation. The effects of sodium vapour condensation on aerosol scrubbing are also treated. This paper provides details of the individual scrubbing mechanisms utilized in the IFR code as well as results from a trial mechanistic source term assessment led by Argonne National Laboratory in 2016.« less

Cold Trap Dismantling and Sodium Removal at a Fast Breeder Reactor - 12327

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graf, A.; Petrick, H.; Stutz, U.

2012-07-01

The first German prototype Fast Breeder Nuclear Reactor (KNK) is currently being dismantled after being the only operating Fast Breeder-type reactor in Germany. As this reactor type used sodium as a coolant in its primary and secondary circuit, seven cold traps containing various amounts of partially activated sodium needed to be disposed of as part of the dismantling. The resulting combined difficulties of radioactive contamination and high chemical reactivity were handled by treating the cold traps differently depending on their size and the amount of sodium contained inside. Six small cold traps were processed onsite by cutting them up intomore » small parts using a band saw under a protective atmosphere. The sodium was then converted to sodium hydroxide by using water. The remaining large cold trap could not be handled in the same way due to its dimensions (2.9 m x 1.1 m) and the declared amount of sodium inside (1,700 kg). It was therefore manually dismantled inside a large box filled with a protective atmosphere, while the resulting pieces were packaged for later burning in a special facility. The experiences gained by KNK during this process may be advantageous for future dismantling projects in similar sodium-cooled reactors worldwide. The dismantling of a prototype fast breeder reactor provides the challenge not only to dismantle radioactive materials but also to handle sodium-contaminated or sodium-containing components. The treatment of sodium requires additional equipment and installations to ensure a safe handling. Since it is not permitted to bring sodium into a repository, all sodium has to be neutralized either through a controlled reaction with water or by incinerating. The resulting components can be disposed of as normal radioactive waste with no further conditions. The handling of sodium needs skilled and experienced workers to minimize the inherent risks. And the example of the disposal of the large KNK cold trap shows the interaction with others and also foreign decommissioning projects can provide solutions with were unknown before. (authors)« less

PH-zone-refining counter-current chromatography with a hydrophilic organic/salt-containing two-phase solvent system for preparative separation of polar alkaloids from natural products.

PubMed

Zou, Denglang; Du, Yurong; Kuang, Jianyuan; Sun, Shihao; Ma, Jianbin; Jiang, Renwang

2018-06-08

This study presents an efficient strategy based on pH-zone-refining counter-current chromatography with a hydrophilic organic/salt-containing two-phase system composed of acetonitrile, sodium chloride and water for preparative separation of polar alkaloids from natural products. Acetonitrile-sodium chloride-water system provides a wider range of polarity for polar alkaloids than classical aqueous two-phase systems. It gets rid of the effect of free hydrogen ion, strong ionic strength, hold low viscosity and the sharp retainer border could be formed easily. So acetonitrile-sodium chloride-water system showed great advantages to pH-zone-refining counter-current chromatography for polar alkaloids. The separation of polar indole alkaloids from toad venom was selected as an example to show the advantage and practicability of this strategy. An optimized acetonitrile-sodium chloride-water (54%:5%:41%, w%) system was applied in this study, where 10 mM triethylamine (TEA) as the retainer and 15 mM hydrochloric acid (HCl) as the eluter were added. As a result, three polar indole alkaloids, including 19 mg of serotonin, 45 mg of 5-Hydroxy-N'-methyl tryptamine, 33 mg of bufotenine were simultaneously separated from 500 mg of 5% ethanol elution fraction of toad venom on macroporous resin chromatography, with the purity of 91.3%, 97.5% and 89.4%, respectively. Their structures were identified by spectroscopic analysis. Copyright © 2018 Elsevier B.V. All rights reserved.

Electrogenic active proton pump in Rana esculenta skin and its role in sodium ion transport.

PubMed

Ehrenfeld, J; Garcia-Romeu, F; Harvey, B J

1985-02-01

Kinetic and electrophysiological studies were carried out in the in vitro Rana esculenta skin, bathed in dilute sodium solution, to characterize the proton pump and coupling between sodium absorption (JNa+n) and proton excretion (JH+n). JNa+n and JH+n were both dependent on transepithelial potential (psi ms); hyperpolarizing the skin decreased JNa+n and increased JH+n; depolarization produced the opposite effects. Amiloride (5 X 10(-5) M) at a clamped psi ms of +50 mV inhibited JNa+n without affecting JH+n. Variations of psi ms or pH had identical effects on JH+n. Ethoxzolamide inhibited JH+n and simultaneously increased psi ms by 15-30 mV. These changes were accompanied by depolarization of the apical membrane potential psi mc from -47 to -25 mV and an increase in apical membrane resistance of 30%; no significant effects on basolateral membrane potential (psi cs) and resistance (Rb) nor on shunt resistance (Rj) were observed. The proton pump appears to be localized at the apical membrane. The proton pump was also inhibited by deoxygenation, oligomycin, dicyclohexylcarbodiimide and vanadate (100, 78, 83 and 100% inhibition respectively). The variations of JH+n and of the measured electrical currents were significantly correlated. These findings are supportive evidence of a primary active proton pump, electrogenic and strictly linked to aerobic metabolism. The current-voltage (I-V) relation of the proton pump was obtained as the difference in the I-V curves of the apical membrane extracted before and after proton-pump inhibition by ethoxzolamide during amiloride block of sodium transport. The proton-pump current (IP) was best described by a saturable exponential function of psi mc. Maximal pump current (ImaxP) was calculated to be 200 nequiv h-1 cm-2 at a psi mc of +50 mV and the pump reversal potential ERP was -130 mV. The effect of ethoxzolamide to depolarize psi mc was dependent on the relation between psi mc and ERP. Maximal induced depolarization occurred at a psi mc of +50 mV whereas ethoxzolamide exerted minimal effect on psi mc when the ERP was approached either by voltage clamping the apical membrane or by the addition of amiloride. We show that electroneutral sodium-proton countertransport is not the mechanism of active proton excretion in frog skin but that it is the proton excretion which provides a favourable electrical driving force for passive apical sodium entry.(ABSTRACT TRUNCATED AT 400 WORDS)

Electrogenic active proton pump in Rana esculenta skin and its role in sodium ion transport.

PubMed Central

Ehrenfeld, J; Garcia-Romeu, F; Harvey, B J

1985-01-01

Kinetic and electrophysiological studies were carried out in the in vitro Rana esculenta skin, bathed in dilute sodium solution, to characterize the proton pump and coupling between sodium absorption (JNa+n) and proton excretion (JH+n). JNa+n and JH+n were both dependent on transepithelial potential (psi ms); hyperpolarizing the skin decreased JNa+n and increased JH+n; depolarization produced the opposite effects. Amiloride (5 X 10(-5) M) at a clamped psi ms of +50 mV inhibited JNa+n without affecting JH+n. Variations of psi ms or pH had identical effects on JH+n. Ethoxzolamide inhibited JH+n and simultaneously increased psi ms by 15-30 mV. These changes were accompanied by depolarization of the apical membrane potential psi mc from -47 to -25 mV and an increase in apical membrane resistance of 30%; no significant effects on basolateral membrane potential (psi cs) and resistance (Rb) nor on shunt resistance (Rj) were observed. The proton pump appears to be localized at the apical membrane. The proton pump was also inhibited by deoxygenation, oligomycin, dicyclohexylcarbodiimide and vanadate (100, 78, 83 and 100% inhibition respectively). The variations of JH+n and of the measured electrical currents were significantly correlated. These findings are supportive evidence of a primary active proton pump, electrogenic and strictly linked to aerobic metabolism. The current-voltage (I-V) relation of the proton pump was obtained as the difference in the I-V curves of the apical membrane extracted before and after proton-pump inhibition by ethoxzolamide during amiloride block of sodium transport. The proton-pump current (IP) was best described by a saturable exponential function of psi mc. Maximal pump current (ImaxP) was calculated to be 200 nequiv h-1 cm-2 at a psi mc of +50 mV and the pump reversal potential ERP was -130 mV. The effect of ethoxzolamide to depolarize psi mc was dependent on the relation between psi mc and ERP. Maximal induced depolarization occurred at a psi mc of +50 mV whereas ethoxzolamide exerted minimal effect on psi mc when the ERP was approached either by voltage clamping the apical membrane or by the addition of amiloride. We show that electroneutral sodium-proton countertransport is not the mechanism of active proton excretion in frog skin but that it is the proton excretion which provides a favourable electrical driving force for passive apical sodium entry.(ABSTRACT TRUNCATED AT 400 WORDS) Images Fig. 6 Fig. 7 PMID:2582114

Development & experimental validation of a SINDA/FLUINT thermal/fluid/electrical model of a multi-tube AMTEC cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hendricks, T.J.; Borkowski, C.A.; Huang, C.

1998-01-01

AMTEC (Alkali Metal Thermal-to-Electric Conversion) cell development has received increased attention and funding in the space power community because of several desirable performance characteristics compared to current radioisotope thermoelectric generation and solar photovoltaic (PV) power generation. AMTEC cell development is critically dependent upon the ability to predict thermal, fluid dynamic and electrical performance of an AMTEC cell which has many complex thermal, fluid dynamic and electrical processes and interactions occurring simultaneously. Development of predictive capability is critical to understanding the complex processes and interactions within the AMTEC cell, and thereby creating the ability to design high-performance, cost-effective AMTEC cells. Amore » flexible, sophisticated thermal/fluid/electrical model of an operating AMTEC cell has been developed using the SINDA/FLUINT analysis software. This model can accurately simulate AMTEC cell performance at any hot side and cold side temperature combination desired, for any voltage and current conditions, and for a broad range of cell design parameters involving the cell dimensions, current collector and electrode design, electrode performance parameters, and cell wall and thermal shield emissivity. The model simulates the thermal radiation network within the AMTEC cell using RadCAD thermal radiation analysis; hot side, cold side and cell wall conductive and radiative coupling; BASE (Beta Alumina Solid Electrode) tube electrochemistry, including electrode over-potentials; the fluid dynamics of the low-pressure sodium vapor flow to the condenser and liquid sodium flow in the wick; sodium condensation at the condenser; and high-temperature sodium evaporation in the wick. The model predicts the temperature profiles within the AMTEC cell walls, the BASE tube temperature profiles, the sodium temperature profile in the artery return, temperature profiles in the evaporator, thermal energy flows throughout the AMTEC cell, all sodium pressure drops from hot BASE tubes to the condenser, the current, voltage, and power output from the cell, and the cell efficiency. This AMTEC cell model is so powerful and flexible that it is used in radioisotope AMTEC power system design, solar AMTEC power system design, and combustion-driven power system design on several projects at Advanced Modular Power Systems, Inc. (AMPS). The model has been successfully validated against actual cell experimental data and its performance predictions agree very well with experimental data on PX-5B cells and other test cells at AMPS. {copyright} {ital 1998 American Institute of Physics.}« less

Extracellular fluid volume expansion and third space sequestration at the site of small bowel anastomoses.

PubMed

Chan, S T; Kapadia, C R; Johnson, A W; Radcliffe, A G; Dudley, H A

1983-01-01

Intestinal surgery is usually associated with the parenteral administration of sodium and water, sometimes in amounts considerably in excess of excretory capacity. We have studied the effect of this situation on the water content of the gut at and 5 cm from a single-layer end-to-end anastomosis in the rabbit. Water content was measured by desiccation. One group of animals (group 1) did not receive intravenous therapy. The second group (group 2) received 5 ml kg-1 h-1 of Hartmann's solution during the operative period and thereafter to a total volume of 200 ml by 48 h. In group 1 there was a 5-10 per cent increase in tissue weight both at the anastomotic site and at 5 cm (P less than 0.01, Mann-Whitney U test) on the first 3 days. Thereafter, water content at the anastomosis persisted, but resolved in normal gut. In group 2 a further 5 per cent increase in weight over group 1 occurred (P less than 0.01), persistent at the anastomotic site over 5 days, though resolving elsewhere after 2 days. Extracellular fluid volume expansion exaggerates an anatomical third space present in the region of an anastomosis. At the suture line, oedema so induced is persistent and could be deleterious.

Continued root maturation despite persistent apical periodontitis of immature permanent teeth after failed regenerative endodontic therapy.

PubMed

Lin, Louis M; Kim, Sahng G; Martin, Gabriela; Kahler, Bill

2018-01-16

Three immature permanent teeth with pulp necrosis and apical periodontitis were treated with regenerative endodontic therapy (RET), which included root canal disinfection with sodium hypochlorite irrigation, intra-canal medication with calcium hydroxide paste, 17% EDTA rinse, induction of periapical bleeding into the canal, collagen matrix and MTA coronal seal, and composite resin restoration of access cavities. After different periods of follow-up, it was observed that continued root maturation, especially apical closure occurred despite persistent apical periodontitis of immature permanent teeth after failed RET. This finding is of interest as the secondary goal of further root maturation occurred despite failure of the primary goal of elimination of clinical symptom/sign and periapical inflammation. The possible biological mechanisms that could allow for further root maturation to occur in spite of persistent root canal infection of immature permanent teeth are discussed. Based on these observations, the biology of wound healing of immature permanent teeth after injury is not fully understood and should be further investigated. This case report demonstrates that whilst further root maturation is considered a successful outcome for teeth treated with RET, the primary objective must be the resolution of the signs and symptoms of apical periodontitis. © 2018 Australian Society of Endodontology Inc.

Spatial patterns of drought persistence in East China

NASA Astrophysics Data System (ADS)

Meng, L.; Ford, T.

2017-12-01

East China has experienced a number of severe droughts in recent decades. Understanding the characteristics of droughts and their persistence will provide operational guidelines for water resource management and agricultural production. This study uses a logistic regression model to measure the probability of drought occurrence in the current season given the previous season's Standardized Precipitation Index (SPI) and Southern Oscillation Index (SOI) as well as drought persistence. Results reveal large spatial and seasonal variations in the relationship between the previous season's SPI and the drought occurrence probability in a given season. The drought persistence averaged over the entire study area for all the four seasons is approximately 34% with large variations from season to season and from region to region. The East and Northeast regions have the largest summer drought persistence ( 40%) and lowest fall drought persistence ( 28%). The spatial pattern in winter and spring drought persistence is dissimilar with stronger winter and weaker spring drought persistence in the Southwest and Northeast relative to other regions. Logistic regression analysis indicates a stronger negative relationship in summer-to-fall (or between fall drought occurrence and summer SPI) than other inter-season relationships. This study demonstrates that the impact of previous season SPI and SOI on current season drought varies substantially from region to region and from season to season. This study also shows stronger drought persistence in summer than in other seasons. In other words, the probability of fall drought occurrence is closely related to summer moisture conditions in the East China.

Optimizing treatment of hypothyroidism.

PubMed

Clarke, Nick; Kabadi, Udaya M

2004-01-01

Several thyroid hormone preparations are currently available, including levothyroxine sodium (thyroxine), liothyronine (triiodothyronine), and desiccated thyroid extract, as well as a combination of levothyroxine sodium and liothyronine. Levothyroxine sodium monotherapy at an appropriate daily dose provides uniform levels of both thyroxine and triiodothyronine in the circulation without diurnal variation. Therefore, it is the preparation of choice in most patients with hypothyroidism of both the primary and central types. A normal thyrotropin (TSH) level of 1-2 mU/L is considered the determinant of optimal daily levothyroxine sodium dose in patients with primary hypothyroidism, whereas normal thyroxine and triiodothyronine levels in the mid or upper normal range may denote optimal replacement in patients with central hypothyroidism. Optimal daily levothyroxine sodium dose may be determined according to serum TSH level at the time of diagnosis of primary hypothyroidism. Initial administration of close to the full calculated dose of levothyroxine sodium is appropriate for younger patients, reducing the need for follow-up visits and repeated laboratory testing for dose titration. In the elderly and in patients with a history of coronary artery disease (CAD), the well established approach of starting with a low dose and gradually titrating to the full calculated dose is always the best option. Levothyroxine sodium can and should be continued in patients receiving treatment for CAD. Even minor over-replacement during initial titration of levothyroxine sodium should be avoided, because of the risk of cardiac events. Chronic over-replacement may induce osteoporosis, particularly in postmenopausal women, and should also be avoided.

Sodium consumption among hypertensive adults advised to reduce their intake: national health and nutrition examination survey, 1999-2004.

PubMed

Ayala, Carma; Gillespie, Cathleen; Cogswell, Molly; Keenan, Nora L; Merritt, Robert

2012-07-01

The authors estimated the prevalence of taking action to reduce intake related to actual sodium consumption among 2970 nonpregnant US adults 18 years and older with self-reported hypertension by using data from the National Health and Nutrition Examination Survey 1999-2004. Adjusted multiple linear regression assessed differences in mean sodium intake by action status. A total of 60.5% of hypertensive adults received advice to reduce sodium intake. Of this group, 83.7% took action to reduce sodium. Action to reduce sodium intake differed significantly by age, race/ethnicity, and use of an antihypertensive. The mean (±standard error) sodium intake among hypertensive adults was 3341±37 mg and differed by sex, age, race/ethnicity, education, and body mass index (P<.05), with the lowest intake among adults aged 65 years and older (2780±48 mg). Mean intake did not differ significantly by action status either overall or by subgroup except for one age category: among patients 65 years and older, mean intake was significantly lower among those who took action (2715±63 mg) than among those who did not (3401±206 mg; P=.0124). Regardless of action, mean intake was well above 1999-2004 recommendations for daily sodium intake and about twice as high as the current recommendation for hypertensive adults (1500 mg). © 2012 Wiley Periodicals, Inc.

Sodium Velocity Maps on Mercury

NASA Technical Reports Server (NTRS)

Potter, A. E.; Killen, R. M.

2011-01-01

The objective of the current work was to measure two-dimensional maps of sodium velocities on the Mercury surface and examine the maps for evidence of sources or sinks of sodium on the surface. The McMath-Pierce Solar Telescope and the Stellar Spectrograph were used to measure Mercury spectra that were sampled at 7 milliAngstrom intervals. Observations were made each day during the period October 5-9, 2010. The dawn terminator was in view during that time. The velocity shift of the centroid of the Mercury emission line was measured relative to the solar sodium Fraunhofer line corrected for radial velocity of the Earth. The difference between the observed and calculated velocity shift was taken to be the velocity vector of the sodium relative to Earth. For each position of the spectrograph slit, a line of velocities across the planet was measured. Then, the spectrograph slit was stepped over the surface of Mercury at 1 arc second intervals. The position of Mercury was stabilized by an adaptive optics system. The collection of lines were assembled into an images of surface reflection, sodium emission intensities, and Earthward velocities over the surface of Mercury. The velocity map shows patches of higher velocity in the southern hemisphere, suggesting the existence of sodium sources there. The peak earthward velocity occurs in the equatorial region, and extends to the terminator. Since this was a dawn terminator, this might be an indication of dawn evaporation of sodium. Leblanc et al. (2008) have published a velocity map that is similar.

Sodium intake, RAAS-blockade and progressive renal disease.

PubMed

de Borst, Martin H; Navis, Gerjan

2016-05-01

Pharmacological blockade of the renin-angiotensin-aldosterone system (RAAS) by angiotensin converting enzyme inhibitors or angiotensin receptor blockers is the current standard treatment to prevent progressive renal function loss in patients with chronic kidney disease. Yet in many patients the renal protective effect of RAAS-blockade is incomplete. Short-term clinical studies have demonstrated that dietary sodium restriction potentiates the antiproteinuric effect of RAAS-blockade. More recently, it was shown that this effect is accompanied by a lower risk of end-stage renal disease and adverse cardiovascular outcomes. The modulation of RAAS-blockade efficacy by sodium intake is likely multifactorial, and is mediated by effects of sodium on local tissue RAAS in kidney, vasculature and brain, and by effects on the immune system. Despite the evidence showing the beneficial effects of even a moderate sodium restriction (∼2.5g/d), it remains difficult to realize in clinical practice. In an analysis based on 24-h urinary sodium excretion data from more than 10,000 CKD patients and renal transplant recipients, we found that sodium intake in these patients is on average 3.8g/d, closely resembling the global general population (3.95g/d). Behavioral approaches including the use of online dietary coaching (ehealth) and feedback using data from 24-h urine collections may be useful to successfully lower dietary sodium intake, aiming to improve cardio-renal outcomes in patients with CKD. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Growth and Protein Expression of Inflammatory Bowel Disease-Associated Campylobacter concisus Is Affected by the Derivatives of the Food Additive Fumaric Acid.

PubMed

Ma, Rena; Liu, Fang; Yap, Soe F; Lee, Hoyul; Leong, Rupert W; Riordan, Stephen M; Grimm, Michael C; Zhang, Li

2018-01-01

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions of the gastrointestinal tract with multifactorial etiology. Both dietary factors and the microbe Campylobacter concisus have been found to be associated with the condition. The current study examined the effects of sodium fumarate, a neutralized product of the food additives fumaric acid and monosodium fumarate when in the intestinal environment, on the growth of C. concisus to determine the effects of these food additives on IBD-associated bacterial species. Through culture methods and quantification, it was found that neutralized fumaric acid, neutralized monosodium fumarate, and sodium fumarate increased the growth of C. concisus , with the greatest increase in growth at a concentration of 0.4%. Further examination of 50 C. concisus strains on media with added sodium fumarate showed that greatest growth was also achieved at a concentration of 0.4%. At a concentration of 2% sodium fumarate, all strains examined displayed less growth in comparison with those cultured on media without sodium fumarate. Using mass spectrometry, multiple C. concisus proteins showed significant differential expression when cultured on media with and without 0.4% sodium fumarate. The findings presented suggest that patients with IBD should consider avoiding excessive consumption of foods with fumaric acid or its sodium salts, and that the addition of 0.4% sodium fumarate alone to media may assist in the isolation of C. concisus from clinical samples.

Development of a Sodium LIDAR for Spaceborne Missions

NASA Technical Reports Server (NTRS)

Yu, Anthony W.; Krainak, Michael A.; Janches, Diego; Jones, Sarah L.; Blagojevic, Branimir; Chen, Jeffrey

2015-01-01

We are currently developing laser and electro-optic technologies to remotely measure Sodium (Na) by adapting existing lidar technology with space flight heritage. The developed instrumentation will serve as the core for the planning of a Heliophysics mission targeted to study the composition and dynamics of Earths mesosphere based on a spaceborne lidar that will measure the mesospheric Na layer. There is a pressing need in the Ionosphere Thermosphere - Mesosphere (ITM) community for high-resolution measurements that can characterize small-scale dynamics (i.e. Gravity Waves with wavelengths smaller than a few hundred km) and their effects in the Mesosphere-Lower-Termosphere (MLT) on a global basis. This is compelling because they are believed to be the dominant contributors to momentum transport and deposition in the MLT, which largely drive the global circulation and thermal structure and interactions with the tides and planetary waves in this region. We are developing a spaceborne remote sensing technique that will enable acquisition of global Na density, temperature and wind measurements in the MLT with the spatial and temporal resolution required to resolve issues associated with the structure, chemistry, dynamics, and energetics of this regionA nadir-pointing spaceborne Na Doppler resonance fluorescence LIDAR on board of the ISS will essentially make high-resolution, in time and space, Na density, temperature and vertical wind measurements, from 75-115 km (MLT region). Our instrument concept consisted of a high-energy laser transmitter at 589 nm and highly sensitive photon counting detector that allows for range-resolved atmospheric-sodium-temperature profiles. The atmospheric temperature is deduced from the linewidth of the resonant fluorescence from the atomic sodium vapor D2 line as measured by our tunable laser. We are currently developing a high power energy laser that allows for some day time sodium lidar observations with the help of a narrow bandpass filter based on etalon or atomic sodium Faraday filter with 5 to 10 pm optical bandwidth. The current baseline detector for the lidar instrument is a 16-channel Photomultiplier Tube with receiver electronics that has been space-qualified for the ICESat-2ATLAS mission. Our technique uses the 16-channels as a photon-number-resolving single detector to provide the required full-spectroscopic sodium lineshape waveform for recovering Mesospheric temperature profiles. In this paper, we will describe our instrument concept for a future Heliophysics space mission based on board of the International Space Station (ISS).

Appropriate anesthesia regimen to control sevoflurane-induced emergence agitation in children; propofol-lidocaine and thiopental sodium-lidocaine: a randomized controlled trial.

PubMed

Rahimzadeh, Poupak; Faiz, Seyed Hamid Reza; Alebouyeh, Mahmood Reza; Dasian, Azadeh; Sayarifard, Azadeh

2014-07-01

Emergence Agitation (EA) is a common problem in pediatric anesthesia. The current study evaluated the effect of intravenous lidocaine combined with propofol or thiopental sodium to control EA by sevoflurane in children. The current study aimed to compare the effectiveness of two anesthesia regimen propofol-lidocaine and thiopental sodium lidocaine to control sevoflurane-induced emergence agitation in children. The study enrolled 120 children aged 12 to 36 months with retinoblastoma who underwent induction of anesthesia with sevoflurane for Eye Examination Under Anesthesia (EUA). Sampling was done at Rasoul-Akram Hospital in Tehran, Iran. The subjects were randomly assigned into four groups including: group one (thiopental sodium-lidocaine [TL]), group two (thiopental sodium-saline [TS]), group three (propofol-lidocaine [PL]), and group four (propofol-saline [PS]). Emergence agitation was assessed by using a five-point scoring scale, every 10 minutes during the first 30 minutes after admission to the recovery room. EA occurred in 24 cases (20%) of children. Incidence of EA in the TS, TL, PS, and PL groups were 21 (70%), 2 (6.7%), 1 (3.3%), and 0 (0%), respectively (P < 0.001). Nausea and vomiting after anesthesia did not occur in any of the patients. After removal of the endotracheal tube, laryngospasm complication occurrence in the TS group (10 cases) was higher than the other groups and no statistically significant difference was observed (P = 0.1). Propofol-lidocaine anesthesia regimen was more effective to control the pediatric emergence agitation than the other combinations.

Organic contaminant removal efficiency of sodium bentonite/clay (BC) mixtures in high permeability regions utilizing reclaimed wastewater: A meso-scale study

NASA Astrophysics Data System (ADS)

Xiao, Yang; Li, Yunkai; Ning, Zigong; Li, Pengxiang; Yang, Peiling; Liu, Chengcheng; Liu, Zhongwei; Xu, Feipeng; Hynds, Paul Dylan

2018-03-01

Wastewater reclamation now represents an effective measure for sustainable water resource management in arid regions, however wastewater components (organic micropollutants) may potentially impact local ecological and/or human health. Previous studies have shown that sodium bentonite/natural clay (BC) mixes may be used to effectively reduce riverbed infiltration in regions characterized by excessively high hydraulic conductivity. Accordingly, the current study sought to investigate the contaminant removal efficiency (Re) of several BC mass ratios in simulated dry riverbeds. Results indicate that the measured Re of NH4+-N, CODcr and BOD5 increased in concurrence with an increasing sodium bentonite ratio, up to a maximum Re of 97.4% (NH4+-N), 55.2% (CODcr), and 51.5% (BOD5). The primary contaminant removal site was shown to be the infiltration-reducing (BC) layer, accounting for approximately 40%, 60%, and 70% of NH4+-N, CODcr and BOD5 removal, respectively. Conversely, the removal efficiency of NO3-N was found to be low (<15%), while total phosphorous (TP) was found to actively leach from the infiltration-reduction layer, resulting in measured TP discharges 2.4-4.8 times those of initial infiltration values. The current study provides a technical baseline for the efficacy of sodium bentonite as an effective bi-functional material in areas utilizing reclaimed water i.e. concurrent reduction of infiltration rates (Function 1) and decontamination of reclaimed wastewater infiltration/recharge (Function 2). Findings indicate that sodium bentonite-clay mixes may represent a feasible alternative for managing recharge of non-potable aquifers with reclaimed wastewater.

Evaluation of a combinatorial approach to prion inactivation using an oxidizing agent, SDS, and proteinase K.

PubMed

Smith, Jodi D; Nicholson, Eric M; Greenlee, Justin J

2013-07-25

Prions demonstrate an unusual resistance to methods effective at inactivating conventional microorganisms. This has resulted in a very tangible and difficult infection control challenge to the medical and veterinary communities, as well as animal agriculture and related industries. Currently accepted practices of harsh chemical treatments such as prolonged exposure to sodium hydroxide or sodium hypochlorite, or autoclaving are not suitable in many situations. Less caustic and more readily applicable treatments to contaminated environments are therefore desirable. We recently demonstrated that exposure of the RML scrapie agent to a commercial product containing sodium percarbonate (SPC-P) with or without sodium dodecyl sulfate (SDS) rendered PrP(Sc) sensitive to proteinase K (PK), but did not eliminate infectivity. The current study was designed to evaluate the efficacy of a combinatorial approach to inactivating prions by exposing RML-positive brain homogenate to SPC-P and SDS followed by PK. Treated samples were evaluated for PrP(Sc)-immunoreactivity by western blot, and residual infectivity by mouse bioassay. Treatment of infected brain homogenate with SPC-P and SDS followed by PK exposure resulted in a 4-5 log10 reduction in infectivity when bioassayed in tga20 mice. This study demonstrates that exposure of the RML scrapie agent to SPC-P and SDS followed by PK markedly reduces, but does not eliminate infectivity. The results of this study encourage further investigation into whether consecutive or concomitant exposure to sodium percarbonate, SDS, and a protease may serve as a viable and non-caustic option for prion inactivation.

Feasibility and Clinical Utility of High-definition Transcranial Direct Current Stimulation in the Treatment of Persistent Hallucinations in Schizophrenia.

PubMed

Bose, A; Shivakumar, V; Chhabra, H; Parlikar, R; Sreeraj, V S; Dinakaran, D; Narayanaswamy, J C; Venkatasubramanian, G

2017-12-01

Persistent auditory verbal hallucination is a clinically significant problem in schizophrenia. Recent studies suggest a promising role for add-on transcranial direct current stimulation (tDCS) in treatment. An optimised version of tDCS, namely high-definition tDCS (HD-tDCS), uses smaller electrodes arranged in a 4x1 ring configuration and may offer more focal and predictable neuromodulation than conventional tDCS. This case report illustrates the feasibility and clinical utility of add-on HD-tDCS over the left temporoparietal junction in a 4x1 ring configuration to treat persistent auditory verbal hallucination in schizophrenia.

A persistent-mode 0.5 T solid-nitrogen-cooled MgB2 magnet for MRI

PubMed Central

Ling, Jiayin; Voccio, John P.; Hahn, Seungyong; Qu, Timing; Bascuñán, Juan; Iwasa, Yukikazu

2017-01-01

This paper presents construction details and test results of a persistent-mode 0.5-T MgB2 magnet developed at the Francis Bitter Magnet Lab, MIT. The magnet, of 276-mm inner diameter and 290-mm outer diameter, consisted of a stack of 8 solenoidal coils with a total height of 460 mm. Each coil was wound with monofilament MgB2 wire, equipped with a persistent-current switch and terminated with a superconducting joint, forming an individual superconducting loop. Resistive solder joints connected the 8 coils in series. The magnet, after being integrated into a testing system, immersed in solid nitrogen, was operated in a temperature range of 10–13 K. A two-stage cryocooler was deployed to cool a radiation shield and the cold mass that included mainly ~60 kg of solid nitrogen and the magnet. The solid nitrogen was capable of providing a uniform and stable cryogenic environment to the magnet. The magnet sustained a 0.47-T magnetic field at its center persistently in a range of 10–13 K. The current in each coil was inversely calculated from the measured field profile to determine the performance of each coil in persistent-mode operation. Persistent-current switches were successfully operated in solid nitrogen for ramping the magnet. They were also designed to absorb magnetic energy in a protection mechanism; its effectiveness was evaluated in an induced quench. PMID:28966476

Molecular and kinetic determinants of local anaesthetic action on sodium channels.

PubMed

French, R J; Zamponi, G W; Sierralta, I E

1998-11-23

(1) Local anaesthetics (LA) rely for their clinical actions on state-dependent inhibition of voltage-dependent sodium channels. (2) Single, batrachoxin-modified sodium channels in planar lipid bilayers allow direct observation of drug-channel interactions. Two modes of inhibition of single-channel current are observed: fast block of the open channels and prolongation of a long-lived closed state, some of whose properties resemble those of the inactivated state of unmodified channels. (3) Analogues of different parts of the LA molecule separately mimic each blocking mode: amines--fast block, and water-soluble aromatics--closed state prolongation. (4) Interaction between a mu-conotoxin derivative and diethylammonium indicate an intrapore site of fast, open-state block. (5) Site-directed mutagenesis studies suggest that hydrophobic residues in transmembrane segment 6 of repeat domain 4 of sodium channels are critical for both LA binding and stabilization of the inactivated state.

High-capacity FeTiO3/C negative electrode for sodium-ion batteries with ultralong cycle life

NASA Astrophysics Data System (ADS)

Ding, Changsheng; Nohira, Toshiyuki; Hagiwara, Rika

2018-06-01

The development of electrode materials which improve both the energy density and cycle life is one of the most challenging issues facing the practical application of sodium-ion batteries today. In this work, FeTiO3/C nanoparticles are synthesized as negative electrode materials for sodium-ion batteries. The electrochemical performance and charge-discharge mechanism of the FeTiO3/C negative electrode are investigated in an ionic liquid electrolyte at 90 °C. The FeTiO3/C negative electrode delivers a high reversible capacity of 403 mAh g-1 at a current rate of 10 mA g-1, and exhibits high rate capability and excellent cycling stability for up to 2000 cycles. The results indicate that FeTiO3/C is a promising negative electrode material for sodium-ion batteries.

Tire-derived carbon composite anodes for sodium-ion batteries

NASA Astrophysics Data System (ADS)

Li, Yunchao; Paranthaman, M. Parans; Akato, Kokouvi; Naskar, Amit K.; Levine, Alan M.; Lee, Richard J.; Kim, Sang-Ok; Zhang, Jinshui; Dai, Sheng; Manthiram, Arumugam

2016-06-01

Hard-carbon materials are considered as one of the most promising anodes for the emerging sodium-ion batteries. Here, we report a low-cost, scalable waste tire-derived carbon as an anode for sodium-ion batteries (SIBs). Tire-derived carbons obtained by pyrolyzing acid-treated tire at 1100 °C, 1400 °C and 1600 °C show capacities of 179, 185 and 203 mAh g-1, respectively, after 100 cycles at a current density of 20 mA g-1 in sodium-ion batteries with good electrochemical stability. The portion of the low-voltage plateau region in the charge-discharge curves increases as the heat-treatment temperature increases. The low-voltage plateau is beneficial to enhance the energy density of the full cell. This study provides a new pathway for inexpensive, environmentally benign and value-added waste tire-derived products towards large-scale energy storage applications.

Efficient Storing Energy Harvested by Triboelectric Nanogenerators Using a Safe and Durable All-Solid-State Sodium-Ion Battery.

PubMed

Hou, Huidan; Xu, Qingkai; Pang, Yaokun; Li, Lei; Wang, Jiulin; Zhang, Chi; Sun, Chunwen

2017-08-01

Storing energy harvested by triboelectric nanogenerators (TENGs) from ambient mechanical motion is still a great challenge for achieving low-cost and environmental benign power sources. Here, an all-solid-state Na-ion battery with safe and durable performance used for efficient storing pulsed energy harvested by the TENG is demonstrated. The solid-state sodium-ion batteries are charged by galvanostatic mode and pulse mode with the TENG, respectively. The all-solid-state sodium-ion battery displays excellent cyclic performance up to 1000 cycles with a capacity retention of about 85% even at a high charge and discharge current density of 48 mA g -1 . When charged by the TENG, an energy conversion efficiency of 62.3% is demonstrated. The integration of TENGs with the safe and durable all-solid-state sodium-ion batteries is potential for providing more stable power output for self-powered systems.

Effect of Sodium Dodecyl Sulphate and Sodium Bromide Additives on Ni–W Nanocoatings.

PubMed

Das, Malay Kumar; Qin, Jiaqian; Zhang, Xinyu; Li, Rongxia; Thueploy, Adisak; Limpanart, Sarintorn; Boonyongmaneerat, Yuttanat; Ma, Mingzhen; Liu, Riping

2017-02-01

Nickel-tungsten (Ni–W) coatings were fabricated by electrodeposition method with varying quantities of sodium dodecyl sulphate and sodium bromide to examine the effects of the aforesaid additives on the coatings. The obtained nanocoatings were studied by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and hardness tester. The hardness, tungsten content and grain size attained a maximum value at current density of 0.15 A/cm²,0.1 A/cm² and 0.1 A/cm², respectively. There was a pronounced impact of both the additives on the microstructure and morphology of the coatings. According to results, there are considerable difference in terms of the impact caused by the additives to the tungsten content, hardness and grain size of the coatings. The obtained results suggest that hardness of coatings is mainly contributed by W content in the deposits.

Sodium Sulfur Technology Program Nastec

NASA Technical Reports Server (NTRS)

Highley, Bob; Somerville, W. Andrew

1992-01-01

The NaSTEC program focuses on developing currently available sodium sulfur cells for use in space applications and investigating the operational parameters of the cells. The specific goals of the program are to determine the operational parameters and verify safety limits of Na/S technology battery cells; test long term zero-g operation; and create a life test database. The program approach and ground and flight test objectives are described in textual and graphic form.

Mount Logan ice core record of tropical and solar influences on Aleutian Low variability: 500-1998 A.D.

NASA Astrophysics Data System (ADS)

Osterberg, Erich C.; Mayewski, Paul A.; Fisher, David A.; Kreutz, Karl J.; Maasch, Kirk A.; Sneed, Sharon B.; Kelsey, Eric

2014-10-01

Continuous, high-resolution paleoclimate records from the North Pacific region spanning the past 1500 years are rare; and the behavior of the Aleutian Low (ALow) pressure center, the dominant climatological feature in the Gulf of Alaska, remains poorly constrained. Here we present a continuous, 1500 year long, calibrated proxy record for the strength of the wintertime (December-March) ALow from the Mount Logan summit (PR Col; 5200 m asl) ice core soluble sodium time series. We show that ice core sodium concentrations are statistically correlated with North Pacific sea level pressure and zonal wind speed. Our ALow proxy record reveals a weak ALow from circa 900-1300 A.D. and 1575-1675 A.D., and a comparatively stronger ALow from circa 500-900 A.D., 1300-1575 A.D., and 1675 A.D. to present. The Mount Logan ALow proxy record shows strong similarities with tropical paleoclimate proxy records sensitive to the El Niño-Southern Oscillation and is consistent with the hypothesis that the Medieval Climate Anomaly was characterized by more persistent La Niña-like conditions while the Little Ice Age was characterized by at least two intervals of more persistent El Niño-like conditions. The Mount Logan ALow proxy record is significantly (p < 0.05) correlated and coherent with solar irradiance proxy records over various time scales, with stronger solar irradiance generally associated with a weaker ALow and La Niña-like tropical conditions. However, a step-like increase in ALow strength during the Dalton solar minimum circa 1820 is associated with enhanced Walker circulation. Furthermore, rising CO2 forcing or internal variability may be masking the twentieth century rise in solar irradiance.

Natriuretic factor, a lasting enigma.

PubMed

Licht, A; Fine, L G; Bourgoignie, J J

1978-01-01

A gel filtration fraction of urine from patients with chronic uremia (natriuretic factor) decreases potential difference, net sodium flux and lumen to peritubular flux of sodium across the isolated rabbit cortical collecting tubule. These effects are consistent with the possibility that natriuretic factor represents a modulator of sodium excretion in the mammalian nephron. Natriuretic factor induces a dose-dependent inhibition of short-circuit current in the isolated toad bladder. By comparing the effects of natriuretic factor to those of a standard unit of reference, it may be possible to develop a quantitative assay for natriuretic factor. The acidic nature of natriuretic factor was confirmed by cation exchange column in a high pressure liquid chromatography system.

An MHD Dynamo Experiment.

NASA Astrophysics Data System (ADS)

O'Connell, R.; Forest, C. B.; Plard, F.; Kendrick, R.; Lovell, T.; Thomas, M.; Bonazza, R.; Jensen, T.; Politzer, P.; Gerritsen, W.; McDowell, M.

1997-11-01

A MHD experiment is being constructed which will have the possibility of showing dynamo action: the self--generation of currents from fluid motion. The design allows sufficient experimental flexibility and diagnostic access to study a variety of issues central to dynamo theory, including mean--field electrodynamics and saturation (backreaction physics). Initially, helical flows required for dynamo action will be driven by propellers embedded in liquid sodium. The flow fields will first be measured using laser doppler velocimetry in a water experiment with an identical fluid Reynolds number. The magnetic field evolution will then be predicted using a MHD code, replacing the water with sodium; if growing magnetic fields are found, the experiment will be repeated with sodium.

Assessment of Xylazine for Euthanasia of Anoles (Anolis carolinensis and Anolis distichus)

PubMed Central

Ascher, Jill M; Bates, Wendy; Ng, Julienne; Messing, Susan; Wyatt, Jeffrey

2012-01-01

Intracoelomic (IC) injection of xylazine was evaluated as a chemical euthanasia method for Anolis lizards (Anolis carolinensis or Anolis distichus). Lizards were allocated into 5 groups of 10 animals each. Each group was euthanized by one of these methods: 10 mg xylazine (100 mg/mL) IC; 10 mg xylazine and 0.5 mg acepromazine (10 mg/mL) IC; 10 mg xylazine IC followed by intracardiac injection of 0.1 mEq KCl (2 mEq/mL) once heart beats were no longer discernable by Doppler; 500 mg/kg 1% NaCO3-buffered MS222 solution IC followed by IC injection of 0.1 mL unbuffered 50% (v/v) MS222 solution (experimental groups); and 1.95 mg sodium pentobarbital, diluted 1:10 in sterile water (38.9 mg/mL) given IC (control group). Compared with those given sodium pentobarbital or MS222, lizards euthanized by using xylazine showed prolonged persistence of purposeful movement after cardiac arrest. Therefore, xylazine is not an acceptable alternative euthanasia agent for use in anoles. PMID:22330873

Assessment of xylazine for euthanasia of anoles (Anolis carolinensis and Anolis distichus).

PubMed

Ascher, Jill M; Bates, Wendy; Ng, Julienne; Messing, Susan; Wyatt, Jeffrey

2012-01-01

Intracoelomic (IC) injection of xylazine was evaluated as a chemical euthanasia method for Anolis lizards (Anolis carolinensis or Anolis distichus). Lizards were allocated into 5 groups of 10 animals each. Each group was euthanized by one of these methods: 10 mg xylazine (100 mg/mL) IC; 10 mg xylazine and 0.5 mg acepromazine (10 mg/mL) IC; 10 mg xylazine IC followed by intracardiac injection of 0.1 mEq KCl (2 mEq/mL) once heart beats were no longer discernable by Doppler; 500 mg/kg 1% NaCO(3)-buffered MS222 solution IC followed by IC injection of 0.1 mL unbuffered 50% (v/v) MS222 solution (experimental groups); and 1.95 mg sodium pentobarbital, diluted 1:10 in sterile water (38.9 mg/mL) given IC (control group). Compared with those given sodium pentobarbital or MS222, lizards euthanized by using xylazine showed prolonged persistence of purposeful movement after cardiac arrest. Therefore, xylazine is not an acceptable alternative euthanasia agent for use in anoles.

[Hypercalciuria].

PubMed

Périmenis, P; Wémeau, J-L; Vantyghem, M-C

2005-12-01

The frequency of hypercalciuria is increasing in western countries with an incidence of nephrolithiasis which can reach 13%. Hypercalciuria appears as an alteration of the calcium transport system (kidney, bowel, bone) which is regulated by calcitriol and parathormone. The aim of this review was to screen etiologies of hypercalciuria taking into account recent genetic advances (calcium epithelial channel and calcium sensing receptor). Hypercalciuria may be favored by nutritional causes (diet rich in calcium, sodium, carbohydrates, proteins, poor in phosphates and potassium). It may also be related to an increase in calcium absorption (vitamin D excess, primary hyperparathyroidism, sarcoidosis, lymphoma, estrogens, and certain genetic causes), an increase in osteoresorption (bone metastasis, myeloma, Paget, hyperthyroidism, immobilization, hypercortisolism and corticosteroid therapy), or a decrease of kidney tubular resorption (diuretics, Cacci and Ricci, acromegally, Bartter, familial dominant hypocalcemia, Fanconi, Dent, familial hypomagnesemia-hypercalciuria syndrome, type 1 distal tubular acidosis, pseudohypoaldosteronism, diabetes). If no cause is identified, persistence of hypercalciuria after instituting a correct diet is defined as idiopathic hypercalciuria. Treatment of the cause is essential in secondary hypercalciuria, in addition to diet (low sodium intake, normocalcic diet, hydration), associated with thiazide diuretics and biphosphonates if necessary.

Use of Sodium Dithionite as Part of a More Efficient Groundwater Restoration Method Following In-situ Recovery of Uranium at the Smith-Ranch Highland Site in Wyoming

NASA Astrophysics Data System (ADS)

Harris, R.; Reimus, P. W.; Ware, D.; Williams, K.; Chu, D.; Perkins, G.; Migdissov, A. A.; Bonwell, C.

2017-12-01

Uranium is primarily mined for nuclear power production using an aqueous extraction technique called in-situ recovery (ISR). ISR can pollute groundwater with residual uranium and other heavy metals. Reverse osmosis and groundwater sweep are currently used to restore groundwater after ISR mining, but are not permanent solutions. Sodium dithionite is being tested as part of a method to more permanently restore groundwater after ISR mining at the Smith-Ranch Highland site in Wyoming. Sodium dithionite is a chemical reductant that can reduce sediments that were oxidized during ISR. The reduced sediments can reduce soluble uranium (VI) in the groundwater to insoluble uranium (IV). Laboratory studies that use sodium dithionite to treat sediments and waters from the site may help predict how it will behave during a field deployment. An aqueous batch experiment showed that sodium dithionite reduced uranium in post-mined untreated groundwater from 38 ppm to less than 1 ppm after 1 day. A sediment reduction batch experiment showed that sodium dithionite-treated sediments were capable of reducing uranium in post-mined untreated groundwater from 38 ppm to 2 ppm after 7 days. One column experiment is showing post-mined sodium dithionite-treated sediments are capable of reducing uranium in post-mined groundwater for over 30 pore volumes past the initial injection. While these results are promising for field deployments of sodium dithionite, another column experiment with sodium dithionite-treated sediments containing uranium rich organic matter is showing net production of uranium instead of uranium uptake. Sodium dithionite appears to liberate uranium from the organic matter. Another sediment reduction experiment is being conducted to further investigate this hypothesis. These experiments are helping guide plans for field deployments of sodium dithionite at uranium ISR mining sites.

US consumer attitudes toward sodium in baby and toddler foods.

PubMed

John, Katherine A; Cogswell, Mary E; Zhao, Lixia; Maalouf, Joyce; Gunn, Janelle P; Merritt, Robert K

2016-08-01

Dietary data from a nationally representative survey indicate about 80% of US toddlers aged 1-3 years consume too much dietary sodium, which can influence their preference for salty foods in later life. Information on consumer attitudes can inform strategies to reduce sodium in baby and toddler foods. Data were obtained from a 2012 online survey sent to a sample of 11636 US adults aged ≥18 years enrolled in a national probability-based consumer panel; 6378 completed the survey and had non-missing responses to the question of interest, "It is important for baby and toddler foods to be low in sodium." Prevalence of agreement was estimated. Logistic regression was used to describe associations of respondent characteristics with agreement. The majority of respondents were non-Hispanic white and had a household income ≥$60,000. About 7 in 10 (68%, 95% CI: 66%-70%) respondents agreed it is important for baby or toddler foods to be low in sodium. More than 6 of 10 respondents in most subgroups agreed. Among parents with a child currently aged <2 years (N = 390), 82% agreed (95% CI: 77%-87%); the highest agreement included parents who thought sodium was very harmful to their own health (92%, 95% CI: 85%-99%) or who were watching/reducing their own sodium intake (95%, 95% CI: 90%-100%). After adjusting for sex, age, race-ethnicity, agreement was most strongly associated with being a parent of a child <2 years, thinking sodium was harmful, and watching/reducing sodium intake (adjusted odds ratios ≥ 2.5, 95% CI's ≠1.0). The majority of respondents including most parents agreed it is important for baby and toddler foods to be low in sodium, suggesting wide consumer support for strategies to lower sodium in these foods. Published by Elsevier Ltd.

Permeation and block of TRPV1 channels by the cationic lidocaine derivative QX-314

PubMed Central

Puopolo, Michelino; Binshtok, Alexander M.; Yao, Gui-Lan; Oh, Seog Bae; Woolf, Clifford J.

2013-01-01

QX-314 (N-ethyl-lidocaine) is a cationic lidocaine derivative that blocks voltage-dependent sodium channels when applied internally to axons or neuronal cell bodies. Coapplication of external QX-314 with the transient receptor potential vanilloid 1 protein (TRPV1) agonist capsaicin produces long-lasting sodium channel inhibition in TRPV1-expressing neurons, suggestive of QX-314 entry into the neurons. We asked whether QX-314 entry occurs directly through TRPV1 channels or through a different pathway (e.g., pannexin channels) activated downstream of TRPV1 and whether QX-314 entry requires the phenomenon of “pore dilation” previously reported for TRPV1. With external solutions containing 10 or 20 mM QX-314 as the only cation, inward currents were activated by stimulation of both heterologously expressed and native TRPV1 channels in rat dorsal root ganglion neurons. QX-314-mediated inward current did not require pore dilation, as it activated within several seconds and in parallel with Cs-mediated outward current, with a reversal potential consistent with PQX-314/PCs = 0.12. QX-314-mediated current was no different when TRPV1 channels were expressed in C6 glioma cells, which lack expression of pannexin channels. Rapid addition of QX-314 to physiological external solutions produced instant partial inhibition of inward currents carried by sodium ions, suggesting that QX-314 is a permeant blocker. Maintained coapplication of QX-314 with capsaicin produced slowly developing reduction of outward currents carried by internal Cs, consistent with intracellular accumulation of QX-314 to concentrations of 50–100 μM. We conclude that QX-314 is directly permeant in the “standard” pore formed by TRPV1 channels and does not require either pore dilation or activation of additional downstream channels for entry. PMID:23303863

Sodium-Doped Mesoporous Ni2P2O7 Hexagonal Tablets for High-Performance Flexible All-Solid-State Hybrid Supercapacitors.

PubMed

Wei, Chengzhen; Cheng, Cheng; Wang, Shanshan; Xu, Yazhou; Wang, Jindi; Pang, Huan

2015-08-01

A simple hydrothermal method has been developed to prepare hexagonal tablet precursors, which are then transformed into porous sodium-doped Ni2P2O7 hexagonal tablets by a simple calcination method. The obtained samples were evaluated as electrode materials for supercapacitors. Electrochemical measurements show that the electrode based on the porous sodium-doped Ni2P2O7 hexagonal tablets exhibits a specific capacitance of 557.7 F g(-1) at a current density of 1.2 A g(-1) . Furthermore, the porous sodium-doped Ni2P2O7 hexagonal tablets were successfully used to construct flexible solid-state hybrid supercapacitors. The device is highly flexible and achieves a maximum energy density of 23.4 Wh kg(-1) and a good cycling stability after 5000 cycles, which confirms that the porous sodium-doped Ni2P2 O7 hexagonal tablets are promising active materials for flexible supercapacitors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Advanced rechargeable sodium batteries with novel cathodes

NASA Technical Reports Server (NTRS)

Distefano, S.; Ratnakumar, B. V.; Bankston, C. P.

1989-01-01

Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium-sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 Wh/kg theoretical). Energy densities in excess of 180 Wh/kg were realized in practical batteries. Other technological advantages include its chemical simplicity, absence of self-discharge, and long cycle life possibility. More recently, other high temperature sodium batteries have come into the spotlight. These systems can be described as follow: Na/Beta Double Prime-Al2O3/NaAlCl4/Metal Dichloride Sodium/metal dichloride systems are colloquially known as the zebra system and are currently being developed for traction and load leveling applications. The sodium-metal dichloride systems appear to offer many of the same advantages of the Na/S system, especially in terms of energy density and chemical simplicity. The metal dichloride systems offer increased safety and good resistance to overcharge and operate over a wide range of temperatures from 150 to 400 C with less corrosion problems.

Electrochemical investigation of MoTe2/rGO composite materials for sodium-ion battery application

NASA Astrophysics Data System (ADS)

Panda, Manas Ranjan; Anish Raj, K.; Sarkar, Ananta; Bao, Qiaoliang; Mitra, Sagar

2018-05-01

2D layered materials are found to be promising anode materials for renewable energy storage devices like sodium and Li-ion batteries and have become attractive options due to their high specific capacity, abundance and low cost. In this work, we synthesized 2D MoTe2 layers embedded in reduced graphene oxide (rGO) anode material for sodium-ion battery applications. 2D MoTe2 was prepared by a solid-state reaction in vacuum at a temperature of 800 °C. The prepared composite material MoTe2/rGO showed excellent electrochemical performance against the sodium metal. The discharge capacity of MoTe2/rGO was observed to be 280 mAh g-1 at a current rate of 1.0 A g-1 for 100 cycles. rGO plays an important role in embedding the MoTe2 structure, thus improving the electrical and mechanical properties, leading to a superior cycling stability and excellent electrochemical performances of MoTe2 for sodium-ion battery applications.

Mechanisms of Sodium Transport in Plants—Progresses and Challenges

PubMed Central

Keisham, Monika; Mukherjee, Soumya; Bhatla, Satish C.

2018-01-01

Understanding the mechanisms of sodium (Na+) influx, effective compartmentalization, and efflux in higher plants is crucial to manipulate Na+ accumulation and assure the maintenance of low Na+ concentration in the cytosol and, hence, plant tolerance to salt stress. Na+ influx across the plasma membrane in the roots occur mainly via nonselective cation channels (NSCCs). Na+ is compartmentalized into vacuoles by Na+/H+ exchangers (NHXs). Na+ efflux from the plant roots is mediated by the activity of Na+/H+ antiporters catalyzed by the salt overly sensitive 1 (SOS1) protein. In animals, ouabain (OU)-sensitive Na+, K+-ATPase (a P-type ATPase) mediates sodium efflux. The evolution of P-type ATPases in higher plants does not exclude the possibility of sodium efflux mechanisms similar to the Na+, K+-ATPase-dependent mechanisms characteristic of animal cells. Using novel fluorescence imaging and spectrofluorometric methodologies, an OU-sensitive sodium efflux system has recently been reported to be physiologically active in roots. This review summarizes and analyzes the current knowledge on Na+ influx, compartmentalization, and efflux in higher plants in response to salt stress. PMID:29495332

Template-Free Synthesis of Sb2S3 Hollow Microspheres as Anode Materials for Lithium-Ion and Sodium-Ion Batteries

NASA Astrophysics Data System (ADS)

Xie, Jianjun; Liu, Li; Xia, Jing; Zhang, Yue; Li, Min; Ouyang, Yan; Nie, Su; Wang, Xianyou

2018-03-01

Hierarchical Sb2S3 hollow microspheres assembled by nanowires have been successfully synthesized by a simple and practical hydrothermal reaction. The possible formation process of this architecture was investigated by X-ray diffraction, focused-ion beam-scanning electron microscopy dual-beam system, and transmission electron microscopy. When used as the anode material for lithium-ion batteries, Sb2S3 hollow microspheres manifest excellent rate property and enhanced lithium-storage capability and can deliver a discharge capacity of 674 mAh g-1 at a current density of 200 mA g-1 after 50 cycles. Even at a high current density of 5000 mA g-1, a discharge capacity of 541 mAh g-1 is achieved. Sb2S3 hollow microspheres also display a prominent sodium-storage capacity and maintain a reversible discharge capacity of 384 mAh g-1 at a current density of 200 mA g-1 after 50 cycles. The remarkable lithium/sodium-storage property may be attributed to the synergetic effect of its nanometer size and three-dimensional hierarchical architecture, and the outstanding stability property is attributed to the sufficient interior void space, which can buffer the volume expansion. [Figure not available: see fulltext.

Transfer matrix approach to the persistent current in quantum rings: Application to hybrid normal-superconducting rings

NASA Astrophysics Data System (ADS)

Nava, Andrea; Giuliano, Rosa; Campagnano, Gabriele; Giuliano, Domenico

2016-11-01

Using the properties of the transfer matrix of one-dimensional quantum mechanical systems, we derive an exact formula for the persistent current across a quantum mechanical ring pierced by a magnetic flux Φ as a single integral of a known function of the system's parameters. Our approach provides exact results at zero temperature, which can be readily extended to a finite temperature T . We apply our technique to exactly compute the persistent current through p -wave and s -wave superconducting-normal hybrid rings, deriving full plots of the current as a function of the applied flux at various system's scales. Doing so, we recover at once a number of effects such as the crossover in the current periodicity on increasing the size of the ring and the signature of the topological phase transition in the p -wave case. In the limit of a large ring size, resorting to a systematic expansion in inverse powers of the ring length, we derive exact analytic closed-form formulas, applicable to a number of cases of physical interest.

Electrophysiology of the mammillary complex in vitro. I. Tuberomammillary and lateral mammillary neurons

NASA Technical Reports Server (NTRS)

Llinas, R. R.; Alonso, A.

1992-01-01

1. The electrophysiological properties of the tuberomammillary and lateral mammillary neurons in the guinea pig mammillary body were studied using an in vitro brain slice preparation. 2. Tuberomammillary (n = 79) neurons were recorded mainly ventral to the lateral mammillary body as well as ventromedially to the fornix within the rostral part of the medial mammillary nucleus. Intracellular staining with horseradish peroxidase (n = 9) and Lucifer yellow (n = 3) revealed that these cells have several thick, long, spiny dendrites emerging from large (20-35 microns) fusiform somata. 3. Most tuberomammillary neurons (66%) fired spontaneously at a relatively low frequency (0.5-10 Hz) at the resting membrane potential. The action potentials were broad (2.3 ms) with a prominent Ca(2+)-dependent shoulder on the falling phase. Deep (17.8 mV), long-lasting spike afterhyperpolarizations were largely Ca(2+)-independent. 4. All tuberomammillary neurons recorded displayed pronounced delayed firing when the cells were activated from a potential negative to the resting level. The cells also displayed a delayed return to the baseline at the break of hyperpolarizing pulses applied from a membrane potential level close to firing threshold. Analysis of the voltage- and time dependence of this delayed rectification suggested the presence of a transient outward current similar to the A current (IA). These were not completely blocked by high concentrations of 4-aminopyridine, whereas the delayed onset of firing was always abolished when voltage-dependent Ca2+ conductances were blocked by superfusion with Cd2+. 5. Tuberomammillary neurons also displayed inward rectification in the hyperpolarizing and, primarily, depolarizing range. Block of voltage-gated Na(+)-dependent conductances with tetrodotoxin (TTX) selectively abolished inward rectification in the depolarizing range, indicating the presence of a persistent low-threshold sodium-dependent conductance (gNap). In fact, persistent TTX-sensitive, plateau potentials were always elicited following Ca2+ block with Cd2+ when K+ currents were reduced by superfusion with tetraethylammonium. 6. The gNap in tuberomammillary neurons may subserve the pacemaker current underlying the spontaneous firing of these cells. The large-amplitude spike afterhyperpolarization of these neurons sets the availability of the transient outward rectifier, which, in conjunction with the pacemaker current, establishes the rate at which membrane potential approaches spike threshold. 7. Repetitive firing elicited by direct depolarization enhanced the spike shoulder of tuberomammillary neurons. Spike trains were followed by a Ca(2+)-dependent, apamine-sensitive, slow afterhyperpolarization. 8. Lateral mammillary neurons were morphologically and electrophysiologically different from tuberomammillary neurons. All lateral mammillary neurons neurons recorded (n = 44) were silent at rest (-60 mV).(ABSTRACT TRUNCATED AT 400 WORDS).

Persistent and energetic bottom-trapped topographic Rossby waves observed in the southern South China Sea.

PubMed

Shu, Yeqiang; Xue, Huijie; Wang, Dongxiao; Chai, Fei; Xie, Qiang; Cai, Shuqun; Chen, Rongyu; Chen, Ju; Li, Jian; He, Yunkai

2016-04-14

Energetic fluctuations with periods of 9-14 days below a depth of 1400 m were observed in the southern South China Sea (SCS) from 5 years of direct measurements. We interpreted such fluctuations as topographic Rossby waves (TRWs) because they obey the dispersion relation. The TRWs persisted from May 24, 2009 to August 23, 2013, and their bottom current speed with a maximum of ~10 cm/s was one order of magnitude greater than the mean current and comparable to the tidal currents near the bottom. The bottom-trapped TRWs had an approximate trapping depth of 325 m and reference wavelength of ~82 km, which were likely excited by eddies above. Upper layer current speed that peaked approximately every 2 months could offer the energy sources for the persistent TRWs in the southern SCS. Energetic bottom-trapped TRWs may have a comparable role in deep circulation to tides in areas with complex topography.

Persistent and energetic bottom-trapped topographic Rossby waves observed in the southern South China Sea

PubMed Central

Shu, Yeqiang; Xue, Huijie; Wang, Dongxiao; Chai, Fei; Xie, Qiang; Cai, Shuqun; Chen, Rongyu; Chen, Ju; Li, Jian; He, Yunkai

2016-01-01

Energetic fluctuations with periods of 9–14 days below a depth of 1400 m were observed in the southern South China Sea (SCS) from 5 years of direct measurements. We interpreted such fluctuations as topographic Rossby waves (TRWs) because they obey the dispersion relation. The TRWs persisted from May 24, 2009 to August 23, 2013, and their bottom current speed with a maximum of ~10 cm/s was one order of magnitude greater than the mean current and comparable to the tidal currents near the bottom. The bottom-trapped TRWs had an approximate trapping depth of 325 m and reference wavelength of ~82 km, which were likely excited by eddies above. Upper layer current speed that peaked approximately every 2 months could offer the energy sources for the persistent TRWs in the southern SCS. Energetic bottom-trapped TRWs may have a comparable role in deep circulation to tides in areas with complex topography. PMID:27075644

FY 2017-Progress Report on the Design and Construction of the Sodium Loop SMT-3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Natesan, K.; Momozaki, Y.

This report provides an update on the design of a forced-convection sodium loop to be used for the evaluation of sodium compatibility of advanced Alloy 709 with emphasis on long term exposures of tensile, creep, fatigue, creep fatigue, and fracture toughness ASTM-size specimens in support of ASME Code qualification and NRC licensing. The report is a deliverable (Level 4) in FY17 (M4AT-17AN1602094), under the Work Package AT-17AN160209, “Sodium Compatibility” performed by Argonne National Laboratory (ANL), as part of the Advanced Materials Program for the Advanced Reactor Technology. This work package enables the development of advanced structural materials by providing corrosion,more » microstructure, and mechanical property data from the standpoint of sodium compatibility of advanced structural alloys. The first sodium loop (SMT-1) with a single tank was constructed in 2011 at ANL and has been in operation for exposure of subsize sheet specimens of advanced alloys at a single temperature. The second sodium loop with dual tanks (SMT-2) was constructed in 2013 and has been in operation for the exposure of subsize sheet specimens of advanced alloys at two different temperatures. The current loop (SMT-3) has been designed to incorporate sufficient chamber capacity to expose a large number of ASTM-size specimens to evaluate the sodium effects on tensile, creep, fatigue, creep-fatigue, and fracture toughness properties, in support of ASME Code Qualification and USNRC Licensing. The design of individual components for the third sodium loop SMT-3 is almost complete. The design also has been sent to an outside vendor for piping analysis to be in compliance with ASME Code. A purchase order has been placed with an outside vendor for the fabrication of major components such as the specimen exposure tanks. However, we have contracted with another vendor to establish the piping design in compliance with ASME design codes. The piping design was completed in FY2017 and the information is being transmitted to the tank fabricator. The SMT-3 loop will be located in Building 206 adjacent to the currently operating SMT-2 loop. In addition, we have demolished the aged power supply system in Building 206 and installed a new transformer, wiring, and power panels for the new loop. Procurement of some of the long lead items such as valves, EM pumps, EM flowmeters, etc. is in progress and will continue in FY 2018. The construction of components such as cold trap, economizers, piping arrangement etc. will be performed in the central shops at ANL. About 150 liters of sodium for the loop will be procured in early FY2018. The loop system is designed to circulate sodium through the sample tanks and the associated loop without an operator for an extended period of time. With the three sodium loops (with single-tank, dual-tank and four–tanks), materials can be tested at different sodium temperatures, and large tensile, creep, fatigue, creep-fatigue, and fracture toughness specimens can be exposed to sodium for extended periods of time and generate data on mechanical properties in support of ASME Code Qualification and USNRC Licensing of advanced Alloy 709 for use as a structural material in SFRs.« less

Sodium bicarbonate on severe metabolic acidosis during prolonged cardiopulmonary resuscitation: a double-blind, randomized, placebo-controlled pilot study.

PubMed

Ahn, Shin; Kim, Youn-Jung; Sohn, Chang Hwan; Seo, Dong Woo; Lim, Kyoung Soo; Donnino, Michael W; Kim, Won Young

2018-04-01

Sodium bicarbonate administration during cardiopulmonary resuscitation (CPR) is controversial. Current guidelines recommend sodium bicarbonate injection in patients with existing metabolic acidosis, but clinical trials, particularly, those involving patients with acidosis, are limited. We aimed to evaluate the efficacy of sodium bicarbonate administration in out-of-hospital cardiac arrest (OHCA) patients with severe metabolic acidosis during prolonged CPR. Prospective, double-blind, randomized placebo-controlled pilot trial was conducted between January 2015 and December 2015, at a single center emergency department (ED). After 10 minutes of CPR, patients who failed to achieve return of spontaneous circulation (ROSC) and with severe metabolic acidosis (pH<7.1 or bicarbonate <10 mEq/L) were enrolled. Sodium bicarbonate (n=25) or normal saline (n=25) were administered. The primary end point was sustained ROSC. The secondary end points were the change of acidosis and good neurologic survival. Sodium bicarbonate group had significant effect on pH (6.99 vs. 6.90, P=0.038) and bicarbonate levels (21.0 vs. 8.0 mEq/L, P=0.007). However, no significant differences showed between sodium bicarbonate and placebo groups in sustained ROSC (4.0% vs. 16.0%, P=0.349) or good neurologic survival at 1 month (0.0% vs. 4.0%, P=1.000). The use of sodium bicarbonate improved acid-base status, but did not improve the rate of ROSC and good neurologic survival. We could not draw a conclusion, but our pilot data could be used to design a larger trial to verify the efficacy of sodium bicarbonate. NCT02303548 (http://www.ClinicalTrials.gov).

Potential, Current, and Ionic Fluxes across the Isolated Retinal Pigment Epithelium and Choroid

PubMed Central

Lasansky, Arnaldo; de Fisch, Felisa W.

1966-01-01

A flux chamber was utilized for in vitro studies of a membrane formed by the retinal pigment epithelium and choroid of the eye of the toad (Bufo arenarum and Bufo marinus). A transmembrane potential of 20 to 30 mv was found, the pigment epithelium surface positive with respect to the choroidal surface. Unidirectional fluxes of chloride, sodium, potassium, and calcium were determined in the absence of an electrochemical potential difference. A net transfer of chloride from pigment epithelium to choroid accounted for a major fraction of the mean short-circuit current. A small net flux of sodium from choroid to pigment epithelium was detected in Bufo marinus. In both species of toads, however, about one-third of the mean short-circuit current remained unaccounted for. Manometric determinations of bicarbonate suggested an uptake of this ion at the epithelial surface of the membrane but did not provide evidence of a relationship between this process and the short-circuit current. PMID:5961357

Final report on the safety assessment of sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, ammonium bisulfite, sodium metabisulfite and potassium metabisulfite.

PubMed

Nair, Bindu; Elmore, Amy R

2003-01-01

Sodium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Potassium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are inorganic salts that function as reducing agents in cosmetic formulations. All except Sodium Metabisulfite also function as hair-waving/straightening agents. In addition, Sodium Sulfite, Potassium Sulfite, Sodium Bisulfite, and Sodium Metabisulfite function as antioxidants. Although Ammonium Sulfite is not in current use, the others are widely used in hair care products. Sulfites that enter mammals via ingestion, inhalation, or injection are metabolized by sulfite oxidase to sulfate. In oral-dose animal toxicity studies, hyperplastic changes in the gastric mucosa were the most common findings at high doses. Ammonium Sulfite aerosol had an acute LC(50) of >400 mg/m(3) in guinea pigs. A single exposure to low concentrations of a Sodium Sulfite fine aerosol produced dose-related changes in the lung capacity parameters of guinea pigs. A 3-day exposure of rats to a Sodium Sulfite fine aerosol produced mild pulmonary edema and irritation of the tracheal epithelium. Severe epithelial changes were observed in dogs exposed for 290 days to 1 mg/m(3) of a Sodium Metabisulfite fine aerosol. These fine aerosols contained fine respirable particle sizes that are not found in cosmetic aerosols or pump sprays. None of the cosmetic product types, however, in which these ingredients are used are aerosolized. Sodium Bisulfite (tested at 38%) and Sodium Metabisulfite (undiluted) were not irritants to rabbits following occlusive exposures. Sodium Metabisulfite (tested at 50%) was irritating to guinea pigs following repeated exposure. In rats, Sodium Sulfite heptahydrate at large doses (up to 3.3 g/kg) produced fetal toxicity but not teratogenicity. Sodium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite were not teratogenic for mice, rats, hamsters, or rabbits at doses up to 160 mg/kg. Generally, Sodium Sulfite, Sodium Metabisulfite, and Potassium Metabisulfite were negative in mutagenicity studies. Sodium Bisulfite produced both positive and negative results. Clinical oral and ocular-exposure studies reported no adverse effects. Sodium Sulfite was not irritating or sensitizing in clinical tests. These ingredients, however, may produce positive reactions in dermatologic patients under patch test. In evaluating the positive genotoxicity data found with Sodium Bisulfite, the equilibrium chemistry of sulfurous acid, sulfur dioxide, bisulfite, sulfite, and metabisulfite was considered. This information, however, suggests that some bisulfite may have been present in genotoxicity tests involving the other ingredients and vice versa. On that basis, the genotoxicity data did not give a clear, consistent picture. In cosmetics, however, the bisulfite form is used at very low concentrations (0.03% to 0.7%) in most products except wave sets. In wave sets, the pH ranges from 8 to 9 where the sulfite form would predominate. Skin penetration would be low due to the highly charged nature of these particles and any sulfite that did penetrate would be converted to sulfate by the enzyme sulfate oxidase. As used in cosmetics, therefore, these ingredients would not present a genotoxicity risk. The Cosmetic Ingredient Review Expert Panel concluded that Sodium Sulfite, Potassium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are safe as used in cosmetic formulations.

Electrolytic treatment of Standard Malaysian Rubber process wastewater.

PubMed

Vijayaraghavan, Krishnan; Ahmad, Desa; Yazid, Ahmad Yuzri Ahmad

2008-01-31

A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5+/-0.1, current density 74.5 mA/cm(2), sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD(5) 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 degrees C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD(5) 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 degrees C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm(2). The observed energy difference was due to the improved conductivity at high sodium chloride content.

Trash to Treasure: From Harmful Algal Blooms to High-Performance Electrodes for Sodium-Ion Batteries.

PubMed

Meng, Xinghua; Savage, Phillip E; Deng, Da

2015-10-20

Harmful algal blooms (HABs) are frequently reported around the globe. HABs are typically caused by the so-called blue-green algae in eutrophic waters. These fast-growing HABs could be a good source for biomass. Unlike terrestrial plants, they need no land or soil. If HABs could be harvested on a large scale, it could not only possible to mitigate the issue of HABs but also provide a source of biomass. Herein, we demonstrate a facile procedure for converting the HABs into a promising high-performance negative-electrode material for sodium-ion batteries (SIBs). The carbon material derived from blue-green algae demonstrated promising electrochemical performance in reversible sodium storage. The algae used in this work was collected directly from Lake Erie during the algal blooms that affected 500 000 residents in Toledo in 2014. The carbon, derived from the freshly collected HABs by calcination in argon without any additional purification process, delivered a highly stable reversible specific capacity (∼230 mAh/g at a testing current of 20 mA/g) with nearly 100% Columbic efficiency in sodium storage. Impressive rate performance was achieved with a capacity of ∼135 mAh/g even after the testing current was increased fivefold. This proof of concept provides a promising route for mitigating the issue of HABs as "trash" and for generating high-capacity, low-cost electrodes for SIBs as "treasure".

Conduction velocity is regulated by sodium channel inactivation in unmyelinated axons innervating the rat cranial meninges

PubMed Central

De Col, Roberto; Messlinger, Karl; Carr, Richard W

2008-01-01

Axonal conduction velocity varies according to the level of preceding impulse activity. In unmyelinated axons this typically results in a slowing of conduction velocity and a parallel increase in threshold. It is currently held that Na+–K+-ATPase-dependent axonal hyperpolarization is responsible for this slowing but this has long been equivocal. We therefore examined conduction velocity changes during repetitive activation of single unmyelinated axons innervating the rat cranial meninges. In direct contradiction to the currently accepted postulate, Na+–K+-ATPase blockade actually enhanced activity-induced conduction velocity slowing, while the degree of velocity slowing was curtailed in the presence of lidocaine (10–300 μm) and carbamazepine (30–500 μm) but not tetrodotoxin (TTX, 10–80 nm). This suggests that a change in the number of available sodium channels is the most prominent factor responsible for activity-induced changes in conduction velocity in unmyelinated axons. At moderate stimulus frequencies, axonal conduction velocity is determined by an interaction between residual sodium channel inactivation following each impulse and the retrieval of channels from inactivation by a concomitant Na+–K+-ATPase-mediated hyperpolarization. Since the process is primarily dependent upon sodium channel availability, tracking conduction velocity provides a means of accessing relative changes in the excitability of nociceptive neurons. PMID:18096592

Elevated Neuronal Excitability Due to Modulation of the Voltage-Gated Sodium Channel Nav1.6 by Aβ1−42

PubMed Central

Wang, Xi; Zhang, Xiao-Gang; Zhou, Ting-Ting; Li, Na; Jang, Chun-Yan; Xiao, Zhi-Cheng; Ma, Quan-Hong; Li, Shao

2016-01-01

Aberrant increases in neuronal network excitability may contribute to the cognitive deficits in Alzheimer's disease (AD). However, the mechanisms underlying hyperexcitability are not fully understood. Such overexcitation of neuronal networks has been detected in the brains of APP/PS1 mice. In the present study, using current-clamp recording techniques, we observed that 12 days in vitro (DIV) primary cultured pyramidal neurons from P0 APP/PS1 mice exhibited a more prominent action potential burst and a lower threshold than WT littermates. Moreover, after treatment with Aβ1−42 peptide, 12 DIV primary cultured neurons showed similar changes, to a greater degree than in controls. Voltage-clamp recordings revealed that the voltage-dependent sodium current density of neurons incubated with Aβ1−42 was significantly increased, without change in the voltage-dependent sodium channel kinetic characteristics. Immunohistochemistry and western blot results showed that, after treatment with Aβ1−42, expressions of Nav and Nav1.6 subtype increased in cultured neurons or APP/PS1 brains compared to control groups. The intrinsic neuronal hyperexcitability of APP/PS1 mice might thus be due to an increased expression of voltage-dependent sodium channels induced by Aβ1−42. These results may illuminate the mechanism of aberrant neuronal networks in AD. PMID:27013956

Centrifugally-spun carbon microfibers and porous carbon microfibers as anode materials for sodium-ion batteries

NASA Astrophysics Data System (ADS)

Dirican, Mahmut; Zhang, Xiangwu

2016-09-01

Natural abundance and low cost of sodium resources bring forward the sodium-ion batteries as a promising alternative to widely-used lithium-ion batteries. However, insufficient energy density and low cycling stability of current sodium-ion batteries hinder their practical use for next-generation smart power grid and stationary storage applications. Electrospun carbon microfibers have recently been introduced as a high-performance anode material for sodium-ion batteries. However, electrospinning is not feasible for mass production of carbon microfibers due to its complex processing condition, low production rate and high cost. Herein, we report centrifugal spinning, a high-rate and low-cost microfiber production method, as an alternative approach to electrospinning for carbon microfiber production and introduce centrifugally-spun carbon microfibers (CMFs) and porous carbon microfibers (PCMFs) as anode materials for sodium-ion batteries. Electrochemical performance results indicated that the highly porous nature of centrifugally-spun PCMFs led to increased Na+ storage capacity and improved cycling stability. The reversible capacity of centrifugally-spun PCMF anodes at the 200th cycle was 242 mAh g-1, which was much higher than that of centrifugally-spun CMFs (143 mAh g-1). The capacity retention and coulombic efficiency of the centrifugally-spun PCMF anodes were 89.0% and 99.9%, respectively, even at the 200th cycle.

Gateways to clinical trials.

PubMed

Bayes, M; Rabasseda, X; Prous, J R

2003-06-01

Gateways to Clinical Trials is a guide to the most recent clinical trials in current literature and congresses. The data in the following tables has been retrieved from the Clinical Studies knowledge area of Prous Science Integrity(R), the drug discovery and development portal, http://integrity.prous.com. This issue focuses on the following selection of drugs: AdGVVEGF121.10, anakinra, andolast, anidulafungin, APC-2059, l-arginine hydrochloride, aripiprazole, arzoxifene hydrochloride, asimadoline; Bexarotene, bimatoprost, bimosiamose, bizelesin, BMS-188667, botulinum toxin type B, bromfenac sodium, bryostatin 1; Cannabidiol, cariporide mesilate, CCI-1004, CDP-571, cerivastatin sodium, clevudine; Dalbavancin, darbepoetin alfa, decitabine, deligoparin sodium, diethylnorspermine, drotrecogin alfa (activated), DTaP-HBV-IPV/Hib-vaccine; E-5564, eculizumab, edodekin alfa, emtricitabine, enfuvirtide, (-)-epigallocatechin gallate, eplerenone, esomeprazole magnesium, etaquine, etoricoxib, ezetimibe; Fesoterodine, fipamezole hydrochloride, fondaparinux sodium, fosamprenavir calcium, frovatriptan, fulvestrant; Gadofosveset sodium, galiximab, ghrelin (human), glufosfamide; Homoharringtonine; Idraparinux sodium, imatinib mesylate, INS-37217; KRN-7000; L-651582, lafutidine, lanthanum carbonate, lenercept, levetiracetam, lusupultide; Magnesium sulfate, melatonin, mepolizumab, midostaurin, morphine hydrochloride, mozavaptan; Natalizumab, nesiritide; OPC-51803, oregovomab, oritavancin; Peginterferon alfa-2(a), pleconaril, plevitrexed, prasterone, pregabalin; Ranibizumab, Ro-31-7453, roxifiban acetate, rubitecan; SCV-07, SHL-749, sho-saiko-to, soblidotin, solifenacin succinate; Tegaserod maleate, telithromycin, tenecteplase, theraCIM, tipifarnib, travoprost; Valdecoxib, vardenafil hydrochloride hydrate, voriconazole; Ximelagatran; Ziprasidone hydrochloride, ZYC-00101. (c) 2003 Prous Science. All rights reserved.

Measuring 20-100 T B-fields using Zeeman splitting of sodium emission lines on a 500 kA pulsed power machine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Banasek, J. T., E-mail: jtb254@cornell.edu; Engelbrecht, J. T.; Pikuz, S. A.

2016-11-15

We have shown that Zeeman splitting of the sodium (Na) D-lines at 5890 and 5896 Å can be used to measure the magnetic field (B-field) produced in high current pulsed power experiments. We have measured the B-field next to a return current conductor in a hybrid X-pinch experiment near a peak current of about 500 kA. Na is deposited on the conductor and then is desorbed and excited by radiation from the hybrid X-pinch. The D-line emission spectrum implies B-fields of about 20 T with a return current post of 4 mm diameter or up to 120 T with amore » return current wire of 0.455 mm diameter. These measurements were consistent or lower than the expected B-field, thereby showing that basic Zeeman splitting can be used to measure the B-field in a pulsed-power-driven high-energy-density (HED) plasma experiment. We hope to extend these measurement techniques using suitable ionized species to measurements within HED plasmas.« less

Sodium channel blockers as therapeutic target for treating epilepsy: recent updates.

PubMed

Zuliani, Valentina; Fantini, Marco; Rivara, Mirko

2012-01-01

The voltage-gated sodium channels (VGSCs) are a family of membrane proteins forming a pore, through which they selectively conduct sodium ions inward and outward cell's plasma membranes in response to variations of membrane potentials, playing a fundamental role in controlling cellular excitability. Growing evidences suggest that abnormal VGSCs are involved in the pathophysiology of both acquired and inherited epilepsy. Approximately two dozen drugs are currently marketed for the treatment of epilepsy and most of them act as sodium channel blockers, preventing the return of the channels to the active state by stabilizing the inactive form. Despite the many drugs on the market, 30% of patients continue to experience seizures even in the presence of optimal doses of AEDs, while others continue to suffer from medication induced side effects. Thus, there is a great need to continue the search for new AEDs that are not only more effective, but also have a better side effects profile. For this reason, many efforts have been made in the recent years to identify new sodium channel blockers for the treatment of epilepsy. These studies have led to different classes of compounds, characterized by a great structural diversity. The aim of this review is to provide an introduction on the structure and function of the sodium channels, followed by a brief historical perspective on the sodium channel blockers in use as anticonvulsant drugs. Moreover, it will focus on the medicinal chemistry of the sodium channel blockers recently published (2008-2011) and the drug design/molecular modeling studies related to the receptor.

The target-specific transporter and current status of diuretics as antihypertensive.

PubMed

Ali, Syed Salman; Sharma, Pramod Kumar; Garg, Vipin Kumar; Singh, Avnesh Kumar; Mondal, Sambhu Charan

2012-04-01

The currently available diuretics increase the urinary excretion of sodium chloride by selective inhibition of specific sodium transporters in the loop of Henle and distal nephron. In recent years, the molecular cloning of the diuretic-sensitive sodium transporters at distal convoluted tubule has improved our understanding of the cellular mechanisms of action of each class of diuretics. Diuretics are tools of considerable therapeutic importance. First, they effectively reduce blood pressure. Loop and thiazide diuretics are secreted from the proximal tubule via the organic anion transporter-1 and exert their diuretic action by binding to the Na(+)-K(+)-2Cl(-) co-transporter type 2 in the thick ascending limb and the Na(+)-Cl(-) co-transporter in the distal convoluted tubule, respectively. Recent studies in animal models suggest that abundance of these ion transporters is affected by long-term diuretic administration. The WHO/ISH guidelines point out that diuretics enhance the efficacy of antihypertensive drugs and will most often be a component of combination therapy. © 2011 The Authors Fundamental and Clinical Pharmacology © 2011 Société Française de Pharmacologie et de Thérapeutique.

Gamma Rhythm Simulations in Alzheimer's Disease

NASA Astrophysics Data System (ADS)

Montgomery, Samuel; Perez, Carlos; Ullah, Ghanim

The different neural rhythms that occur during the sleep-wake cycle regulate the brain's multiple functions. Memory acquisition occurs during fast gamma rhythms during consciousness, while slow oscillations mediate memory consolidation and erasure during sleep. At the neural network level, these rhythms are generated by the finely timed activity within excitatory and inhibitory neurons. In Alzheimer's Disease (AD) the function of inhibitory neurons is compromised due to an increase in amyloid beta (A β) leading to elevated sodium leakage from extracellular space in the hippocampus. Using a Hodgkin-Huxley formalism, heightened sodium leakage current into inhibitory neurons is observed to compromise functionality. Using a simple two neuron system it was observed that as the conductance of the sodium leakage current is increased in inhibitory neurons there is a significant decrease in spiking frequency regarding the membrane potential. This triggers a significant increase in excitatory spiking leading to aberrant network behavior similar to that seen in AD patients. The next step is to extend this model to a larger neuronal system with varying synaptic densities and conductance strengths as well as deterministic and stochastic drives.

[A survey on the sodium content of customers' orderings at three restaurants in Beijing].

PubMed

Zhao, Nanxi; Liang, Baojing; He, Pingping; Li, Liming; Lyu, Jun

2014-04-01

To survey the mean sodium content of menu offering and customers' orderings on sodium when eating out. All weights of ingredients of menu offerings at three Chinese restaurants with Wenzhou, Shandong, and Yunnan cuisine, in Beijing, were collected and their sodium values were estimated based on data from the Chinese Food Composition. All records from customers' orders were collected in a certain period of time from year 2011 to 2013. The mean sodium content of ordering per person and the proportion of all orders exceeding the recommended daily sodium limit that applicable to most native Chinese, were estimated. Of all the menu offerings, hot dishes (1 728.6 mg; P25, P75: 1 198.7, 2 482.8) and soup dishes (2 101.5 mg; P25, P75: 1 467.8, 2 291.2) had the highest sodium contents, followed by cold dressed dishes (790.7 mg; P25, P75: 128.1, 1 472.9) staple foods (802.9 mg; P25, P75: 115.1, 1 563.2) while the beverages having the lowest sodium contents (17.0 mg; P25, P 75: 2.0, 19.5) (P < 0.05). Meat dishes (1 796.3 mg; P25, P75: 1 303.9, 2 670.3) contained more sodium than vegetable dishes (1 105.5 mg; P25, P75: 423.6, 1 628.6) (P < 0.001). The median sodium contents in per person orderings were 2 325.6 mg (P25, P75:1 700.7, 3 213.8) for lunch and 2 542.5 mg (P25, P75: 1 857.5, 3 498.1) for dinner. Current dietary guideline recommended for Chinese adults was: in general, the amount of consumption should not exceed 2 400 mg of sodium per day. Based on the recommended optimal daily calories intake ratio as 3:4:3 for breakfast, lunch, and dinner, we would suggest that the sodium intake should follow the amount as 960 mg for lunch and 720 mg for dinner. Our data indicated that 97.5% of the ordered meals appeared that they were over the recommended sodium limit and 76.5% of the tables showed two times more than the limit of recommendation. Soup and hot dishes provided at these three restaurants contained more sodium contents. People ordered dishes at restaurants would contain more sodium than the recommended Chinese daily sodium intake.

Decontamination of soil containing POPs by the combined action of solid Fenton-like reagents and microwaves.

PubMed

Cravotto, Giancarlo; Di Carlo, Stefano; Ondruschka, Bernd; Tumiatti, Vander; Roggero, Carlo Maria

2007-10-01

The effect on halogenated aromatics of solid, non-toxic oxidants such as sodium percarbonate and the urea/hydrogen peroxide complex (Fenton-like reagents) was investigated. A microwaves-assisted, solvent-free method for soil decontamination is presented. It marks a considerable advance in the search of more efficient, environment-friendly procedures for the degradative oxidation of persistent organic pollutants. Residual pollutants in treated soil samples were determined by GC/MS analysis after solvent extraction or direct thermal desorption. Results showed that 4-chloronaphthol, 2,4-dichlorophenoxyacetic acid and p-nonylphenol had been degraded completely, 2,4-dibromophenol to a large extent.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cobden, I.; Shore, A.; Wilkinson, R.

Five patients with hepatorenal syndrome were treated with the orally active angiotensin-converting enzyme inhibitor captopril (25 or 50 mg 6 hourly) for up to 48 hours. Only one patient showed a significant increase in urinary sodium concentration (from less than 10 to 70 mmol/liter), but without associated diuresis; renal function continued to deteriorate in all patients with persistent oliguria and rising serum creatinine. The outcome was uniformly fatal. These results suggest that in the hepatorenal syndrome, captopril in standard dosage is without benefit, and provide further evidence that the changes in the renin-angiotensin system are probably secondary to reduced renalmore » perfusion from some other cause.« less

Incidental Detection of Dent-2 Disease in an Infant with "Febrile Proteinuria".

PubMed

Salihu, Shpetim; Tosheska, Katerina; Cekovska, Svetlana; Tasic, Velibor

2018-05-17

Febrile proteinuria is functional proteinuria and is seen as a transitory phenomenon during acute febrile illness, mainly viral infections. It is a benign phenomenon and clears promptly with resolution of the infection. In this report, we present a patient who was thought to have febrile proteinuria. Persistence of significant proteinuria after resolution of the infection prompted biochemical and genetic work-up which lead to the diagnosis of Dent-2 disease. We recommend the use of sodium dodecyl sulphate electropheresis (SDS-PAGE) for the detection of low molecular weight proteinuria. ©2018The Author(s). Published by S. Karger AG, Basel.

Neural evidence reveals the rapid effects of reward history on selective attention.

PubMed

MacLean, Mary H; Giesbrecht, Barry

2015-05-05

Selective attention is often framed as being primarily driven by two factors: task-relevance and physical salience. However, factors like selection and reward history, which are neither currently task-relevant nor physically salient, can reliably and persistently influence visual selective attention. The current study investigated the nature of the persistent effects of irrelevant, physically non-salient, reward-associated features. These features affected one of the earliest reliable neural indicators of visual selective attention in humans, the P1 event-related potential, measured one week after the reward associations were learned. However, the effects of reward history were moderated by current task demands. The modulation of visually evoked activity supports the hypothesis that reward history influences the innate salience of reward associated features, such that even when no longer relevant, nor physically salient, these features have a rapid, persistent, and robust effect on early visual selective attention. Copyright © 2015 Elsevier B.V. All rights reserved.

Data Service: Distributed Data Capture and Replication

NASA Astrophysics Data System (ADS)

Warner, P. B.; Pietrowicz, S. R.

2007-10-01

Data Service is a critical component of the NOAO Data Management and Science Support (DMaSS) Solutions Platform, which is based on a service-oriented architecture, and is to replace the current NOAO Data Transport System. Its responsibilities include capturing data from NOAO and partner telescopes and instruments and replicating the data across multiple (currently six) storage sites. Java 5 was chosen as the implementation language, and Java EE as the underlying enterprise framework. Application metadata persistence is performed using EJB and Hibernate on the JBoss Application Server, with PostgreSQL as the persistence back-end. Although potentially any underlying mass storage system may be used as the Data Service file persistence technology, DTS deployments and Data Service test deployments currently use the Storage Resource Broker from SDSC. This paper presents an overview and high-level design of the Data Service, including aspects of deployment, e.g., for the LSST Data Challenge at the NCSA computing facilities.

Leveraging Cancer Therapeutics for the HIV Cure Agenda: Current Status and Future Directions

PubMed Central

Polizzotto, Mark N.; Chen, Grace; Tressler, Randall L.; Godfrey, Catherine

2015-01-01

Despite effective antiretroviral therapy (ART) and undetectable HIV RNA in the plasma, latent replication-competent HIV persists indefinitely in long-lived cells. Cessation of ART results in rebound of HIV from these persistent reservoirs. While this was thought to be an insurmountable obstacle to viral eradication, recent cases suggest otherwise. To date one patient has been “cured” of HIV and several others have been able to interrupt ART without viral rebound for prolonged periods. These events have sparked renewed interest in developing strategies that will allow eradication of HIV in infected individuals. We review the current knowledge of HIV latency and the viral reservoir, describe the potential utility of emerging cancer therapeutics in HIV cure research with an emphasis on pathways implicated in reservoir persistence, and outline opportunities and challenges in the context of the current clinical trial and regulatory environment. PMID:26224205

Leveraging Cancer Therapeutics for the HIV Cure Agenda: Current Status and Future Directions.

PubMed

Polizzotto, Mark N; Chen, Grace; Tressler, Randall L; Godfrey, Catherine

2015-09-01

Despite effective antiretroviral therapy (ART) and undetectable HIV RNA in the plasma, latent replication-competent HIV persists indefinitely in long-lived cells. Cessation of ART results in rebound of HIV from these persistent reservoirs. While this was thought to be an insurmountable obstacle to viral eradication, recent cases suggest otherwise. To date one patient has been "cured" of HIV and several others have been able to interrupt ART without viral rebound for prolonged periods. These events have sparked renewed interest in developing strategies that will allow eradication of HIV in infected individuals. We review the current knowledge of HIV latency and the viral reservoir, describe the potential utility of emerging cancer therapeutics in HIV cure research with an emphasis on pathways implicated in reservoir persistence, and outline opportunities and challenges in the context of the current clinical trial and regulatory environment.

Controlled parity switch of persistent currents in quantum ladders

NASA Astrophysics Data System (ADS)

Filippone, Michele; Bardyn, Charles-Edouard; Giamarchi, Thierry

2018-05-01

We investigate the behavior of persistent currents for a fixed number of noninteracting fermions in a periodic quantum ladder threaded by Aharonov-Bohm and transverse magnetic fluxes Φ and χ . We show that the coupling between ladder legs provides a way to effectively change the ground-state fermion-number parity, by varying χ . Specifically, we demonstrate that varying χ by 2 π (one flux quantum) leads to an apparent fermion-number parity switch. We find that persistent currents exhibit a robust 4 π periodicity as a function of χ , despite the fact that χ →χ +2 π leads to modifications of order 1 /N of the energy spectrum, where N is the number of sites in each ladder leg. We show that these parity-switch and 4 π periodicity effects are robust with respect to temperature and disorder, and outline potential physical realizations using cold atomic gases and photonic lattices, for bosonic analogs of the effects.

Feedback control of persistent-current oscillation based on the atomic-clock technique

NASA Astrophysics Data System (ADS)

Yu, Deshui; Dumke, Rainer

2018-05-01

We propose a scheme of stabilizing the persistent-current Rabi oscillation based on the flux qubit-resonator-atom hybrid structure. The low-Q L C resonator weakly interacts with the flux qubit and maps the persistent-current Rabi oscillation of the flux qubit onto the intraresonator electric field. This oscillating electric field is further coupled to a Rydberg-Rydberg transition of the 87Rb atoms. The Rabi-frequency fluctuation of the flux qubit is deduced from measuring the atomic population via the fluorescence detection and stabilized by feedback controlling the external flux bias. Our numerical simulation indicates that the feedback-control method can efficiently suppress the background fluctuations in the flux qubit, especially in the low-frequency limit. This technique may be extensively applicable to different types of superconducting circuits, paving a way to long-term-coherence superconducting quantum information processing.

Central pontine and extrapontine myelinolysis in an infant associated with the treatment of craniopharyngioma: case report.

PubMed

Tsutsumi, Satoshi; Yasumoto, Yukimasa; Ito, Masanori

2008-08-01

A 3-year-old girl presented with osmotic demyelination syndrome after undergoing uneventful neuroendoscopic cystostomy for a growing cystic suprasellar craniopharyngioma following microscopic subtotal resection 1 year previously. Endocrinopathy had well been controlled by hormone replacement therapy and administration of 1-amino-8-d-arginine-vasopressin with serum sodium concentration within the normal range. She presented generalized seizure and fever on postoperative day 7, with hyponatremia beginning on postoperative day 4 and deteriorating despite frequent correction. The serum sodium concentration began to fluctuate on the same day, in the range 111-164 mEq/l, which lasted for 2 weeks, refractory for intense management. Her body temperature also fluctuated between hypo- and hyperthermia not correlated with serum inflammatory markers. Her conscious disturbance progressively deteriorated with spastic paraparesis. T(2)-weighted magnetic resonance (MR) imaging taken on postoperative day 19 revealed hyperintense areas in the pons, external capsule, bilateral thalami, and basal nuclei, which had not been recognized before, suggesting osmotic demyelination syndrome causing central pontine and extrapontine myelinolysis. MR imaging taken on postoperative days 230 and 360 showed some diminished lesions but others persisted and resulted in a cavity. The patient's depressed conscious level did not improve. Suprasellar craniopharyngioma with long-standing hypothalamic dysfunction may be associated with severe osmotic demyelination syndrome even after less invasive surgery, so serum sodium derangement after surgery should be promptly corrected even if only subtle signs are present.

Synergistic Effects of Sodium Chloride, Glucose, and Temperature on Biofilm Formation by Listeria monocytogenes Serotype 1/2a and 4b Strains ▿ † ‡

PubMed Central

Pan, Youwen; Breidt, Frederick; Gorski, Lisa

2010-01-01

Biofilm formation by Listeria monocytogenes is generally associated with its persistence in the food-processing environment. Serotype 1/2a strains make up more than 50% of the total isolates recovered from food and the environment, while serotype 4b strains are most often associated with major outbreaks of human listeriosis. Using a microplate assay with crystal violet staining, we examined biofilm formation by 18 strains of each serotype in tryptic soy broth with varying concentrations of glucose (from 0.25% to 10.0%, wt/vol), sodium chloride (from 0.5% to 7.0%, wt/vol) and ethanol (from 1% to 5.0%, vol/vol), and at different temperatures (22.5°C, 30°C, and 37°C). A synergistic effect on biofilm formation was observed for glucose, sodium chloride, and temperature. The serotype 1/2a strains generally formed higher-density biofilms than the 4b strains under most conditions tested. Interestingly, most serotype 4b strains had a higher growth rate than the 1/2a strains, suggesting that the growth rate may not be directly related to the capacity for biofilm formation. Crystal violet was found to stain both bacterial cells and biofilm matrix material. The enhancement in biofilm formation by environmental factors was apparently due to the production of extracellular polymeric substances instead of the accumulation of viable biofilm cells. PMID:20048067

Seizure control through genetic and pharmacological manipulation of Pumilio in Drosophila: a key component of neuronal homeostasis.

PubMed

Lin, Wei-Hsiang; Giachello, Carlo N G; Baines, Richard A

2017-02-01

Epilepsy is a significant disorder for which approximately one-third of patients do not respond to drug treatments. Next-generation drugs, which interact with novel targets, are required to provide a better clinical outcome for these individuals. To identify potential novel targets for antiepileptic drug (AED) design, we used RNA sequencing to identify changes in gene transcription in two seizure models of the fruit fly Drosophila melanogaster The first model compared gene transcription between wild type (WT) and bangsenseless 1 (para bss ), a gain-of-function mutant in the sole fly voltage-gated sodium channel (paralytic). The second model compared WT with WT fed the proconvulsant picrotoxin (PTX). We identified 743 genes (FDR≤1%) with significant altered expression levels that are common to both seizure models. Of these, 339 are consistently upregulated and 397 downregulated. We identify pumilio (pum) to be downregulated in both seizure models. Pum is a known homeostatic regulator of action potential firing in both flies and mammals, achieving control of neuronal firing through binding to, and regulating translation of, the mRNA transcripts of voltage-gated sodium channels (Na v ). We show that maintaining expression of pum in the CNS of para bss flies is potently anticonvulsive, whereas its reduction through RNAi-mediated knockdown is proconvulsive. Using a cell-based luciferase reporter screen, we screened a repurposed chemical library and identified 12 compounds sufficient to increase activity of pum Of these compounds, we focus on avobenzone, which significantly rescues seizure behaviour in para bss flies. The mode of action of avobenzone includes potentiation of pum expression and mirrors the ability of this homeostatic regulator to reduce the persistent voltage-gated Na + current (I NaP ) in an identified neuron. This study reports a novel approach to suppress seizure and highlights the mechanisms of neuronal homeostasis as potential targets for next-generation AEDs. © 2017. Published by The Company of Biologists Ltd.

Mechanism and molecular basis for the sodium channel subtype specificity of µ-conopeptide CnIIIC

PubMed Central

Markgraf, René; Leipold, Enrico; Schirmeyer, Jana; Paolini-Bertrand, Marianne; Hartley, Oliver; Heinemann, Stefan H

2012-01-01

BACKGROUND AND PURPOSE Voltage-gated sodium channels (NaV channels) are key players in the generation and propagation of action potentials, and selective blockade of these channels is a promising strategy for clinically useful suppression of electrical activity. The conotoxin µ-CnIIIC from the cone snail Conus consors exhibits myorelaxing activity in rodents through specific blockade of skeletal muscle (NaV1.4) NaV channels. EXPERIMENTAL APPROACH We investigated the activity of µ-CnIIIC on human NaV channels and characterized its inhibitory mechanism, as well as the molecular basis, for its channel specificity. KEY RESULTS Similar to rat paralogs, human NaV1.4 and NaV1.2 were potently blocked by µ-CnIIIC, the sensitivity of NaV1.7 was intermediate, and NaV1.5 and NaV1.8 were insensitive. Half-channel chimeras revealed that determinants for the insensitivity of NaV1.8 must reside in both the first and second halves of the channel, while those for NaV1.5 are restricted to domains I and II. Furthermore, domain I pore loop affected the total block and therefore harbours the major determinants for the subtype specificity. Domain II pore loop only affected the kinetics of toxin binding and dissociation. Blockade by µ-CnIIIC of NaV1.4 was virtually irreversible but left a residual current of about 5%, reflecting a ‘leaky’ block; therefore, Na+ ions still passed through µ-CnIIIC-occupied NaV1.4 to some extent. TTX was excluded from this binding site but was trapped inside the pore by µ-CnIIIC. CONCLUSION AND IMPLICATIONS Of clinical significance, µ-CnIIIC is a potent and persistent blocker of human skeletal muscle NaV1.4 that does not affect activity of cardiac NaV1.5. PMID:22537004

Effective silencing of ENaC by siRNA delivered with epithelial-targeted nanocomplexes in human cystic fibrosis cells and in mouse lung.

PubMed

Tagalakis, Aristides D; Munye, Mustafa M; Ivanova, Rositsa; Chen, Hanpeng; Smith, Claire M; Aldossary, Ahmad M; Rosa, Luca Z; Moulding, Dale; Barnes, Josephine L; Kafetzis, Konstantinos N; Jones, Stuart A; Baines, Deborah L; Moss, Guy W J; O'Callaghan, Christopher; McAnulty, Robin J; Hart, Stephen L

2018-05-10

Loss of the cystic fibrosis transmembrane conductance regulator in cystic fibrosis (CF) leads to hyperabsorption of sodium and fluid from the airway due to upregulation of the epithelial sodium channel (ENaC). Thickened mucus and depleted airway surface liquid (ASL) then lead to impaired mucociliary clearance. ENaC regulation is thus a promising target for CF therapy. Our aim was to develop siRNA nanocomplexes that mediate effective silencing of airway epithelial ENaC in vitro and in vivo with functional correction of epithelial ion and fluid transport. We investigated translocation of nanocomplexes through mucus and their transfection efficiency in primary CF epithelial cells grown at air-liquid interface (ALI).Short interfering RNA (SiRNA)-mediated silencing was examined by quantitative RT-PCR and western analysis of ENaC. Transepithelial potential (V t ), short circuit current (I sc ), ASL depth and ciliary beat frequency (CBF) were measured for functional analysis. Inflammation was analysed by histological analysis of normal mouse lung tissue sections. Nanocomplexes translocated more rapidly than siRNA alone through mucus. Transfections of primary CF epithelial cells with nanocomplexes targeting αENaC siRNA, reduced αENaC and βENaC mRNA by 30%. Transfections reduced V t , the amiloride-sensitive I sc and mucus protein concentration while increasing ASL depth and CBF to normal levels. A single dose of siRNA in mouse lung silenced ENaC by approximately 30%, which persisted for at least 7 days. Three doses of siRNA increased silencing to approximately 50%. Nanoparticle-mediated delivery of ENaCsiRNA to ALI cultures corrected aspects of the mucociliary defect in human CF cells and offers effective delivery and silencing in vivo. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

SGLT2 Inhibition in the Diabetic Kidney—From Mechanisms to Clinical Outcome

PubMed Central

Muskiet, Marcel H.A.; Tonneijck, Lennart; Kramer, Mark H.H.; Nieuwdorp, Max; van Raalte, Daniel H.

2017-01-01

Diabetic kidney disease not only has become the leading cause for ESRD worldwide but also, highly contributes to increased cardiovascular morbidity and mortality in type 2 diabetes. Despite increased efforts to optimize renal and cardiovascular risk factors, like hyperglycemia, hypertension, obesity, and dyslipidemia, they are often insufficiently controlled in clinical practice. Although current drug interventions mostly target a single risk factor, more substantial improvements of renal and cardiovascular outcomes can be expected when multiple factors are improved simultaneously. Sodium-glucose cotransporter type 2 in the renal proximal tubule reabsorbs approximately 90% of filtered glucose. In type 2 diabetes, the maladaptive upregulation of sodium-glucose cotransporter type 2 contributes to the maintenance of hyperglycemia. Inhibiting these transporters has been shown to effectively improve glycemic control through inducing glycosuria and is generally well tolerated, although patients experience more genital infections. In addition, sodium-glucose cotransporter type 2 inhibitors favorably affect body weight, BP, serum uric acid, and glomerular hyperfiltration. Interestingly, in the recently reported first cardiovascular safety trial with a sodium-glucose cotransporter type 2 inhibitor, empagliflozin improved both renal and cardiovascular outcomes in patients with type 2 diabetes and established cardiovascular disease. Because the benefits were seen rapidly after initiation of therapy and other glucose-lowering agents, with the exception of liraglutide and semaglutide, have not been able to improve cardiovascular outcome, these observations are most likely explained by effects beyond glucose lowering. In this mini review, we present the drug class of sodium-glucose cotransporter type 2 inhibitors, elaborate on currently available renal and cardiovascular outcome data, and discuss how the effects of these agents on renal physiology may explain the data. PMID:28254770

Activity of the anticonvulsant lacosamide in experimental and human epilepsy via selective effects on slow Na+ channel inactivation.

PubMed

Holtkamp, Dominik; Opitz, Thoralf; Niespodziany, Isabelle; Wolff, Christian; Beck, Heinz

2017-01-01

In human epilepsy, pharmacoresistance to antiepileptic drug therapy is a major problem affecting ~30% of patients with epilepsy. Many classical antiepileptic drugs target voltage-gated sodium channels, and their potent activity in inhibiting high-frequency firing has been attributed to their strong use-dependent blocking action. In chronic epilepsy, a loss of use-dependent block has emerged as a potential cellular mechanism of pharmacoresistance for anticonvulsants acting on voltage-gated sodium channels. The anticonvulsant drug lacosamide (LCM) also targets sodium channels, but has been shown to preferentially affect sodium channel slow inactivation processes, in contrast to most other anticonvulsants. We used whole-cell voltage clamp recordings in acutely isolated cells to investigate the effects of LCM on transient Na + currents. Furthermore, we used whole-cell current clamp recordings to assess effects on repetitive action potential firing in hippocampal slices. We show here that LCM exerts its effects primarily via shifting the slow inactivation voltage dependence to more hyperpolarized potentials in hippocampal dentate granule cells from control and epileptic rats, and from patients with epilepsy. It is important to note that this activity of LCM was maintained in chronic experimental and human epilepsy. Furthermore, we demonstrate that the efficacy of LCM in inhibiting high-frequency firing is undiminished in chronic experimental and human epilepsy. Taken together, these results show that LCM exhibits maintained efficacy in chronic epilepsy, in contrast to conventional use-dependent sodium channel blockers such as carbamazepine. They also establish that targeting slow inactivation may be a promising strategy for overcoming target mechanisms of pharmacoresistance. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grabaskas, David; Bucknor, Matthew; Jerden, James

2016-02-01

The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish releasemore » fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.« less

Ion transport across an isolated preparation of sheep rumen epithelium

PubMed Central

Ferreira, H. G.; Harrison, F. A.; Keynes, R. D.; Zurich, L.

1972-01-01

1. The fluxes of isotopically labelled sodium, potassium and chloride passing in each direction across isolated sheets of rumen epithelium from the sheep have been measured under short-circuit conditions. 2. With both sides of the epithelium bathed in chloride Ringer the mean sodium fluxes were 2·85 μmole/cm2.hr from rumen to blood and 1·28 μmole/cm2.hr in the reverse direction. In sulphate Ringer the sodium fluxes were 1·64 μmole/cm2.hr from rumen to blood and 0·54 μmole/cm2.hr from blood to rumen. 3. In chloride Ringer the mean potassium fluxes were 0·18 μmole/cm2.hr from rumen to blood and 0·54 μmole/cm2.hr from blood to rumen. In sulphate Ringer the potassium fluxes were 0·07 μmole/cm2.hr from rumen to blood and 0·35 μmole/cm2.hr from blood to rumen. 4. In chloride Ringer the mean chloride fluxes were 4·89 μmole/cm2.hr from rumen to blood and 3·78 μmole/cm2.hr from blood to rumen. 5. In chloride Ringer the mean value of the short-circuit current was 13 μA/cm2, corresponding to a flux of 0·49 μequiv/cm2.hr. When sulphate was substituted for chloride, the short-circuit current was increased by about 40%, and the net flux of sodium from rumen to blood fell by 30%. 6. Neither the sodium nor the chloride fluxes changed significantly when the epithelium was temporarily open-circuited. PMID:5037110

MELCOR/CONTAIN LMR Implementation Report. FY14 Progress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humphries, Larry L; Louie, David L.Y.

2014-10-01

This report describes the preliminary implementation of the sodium thermophysical properties and the design documentation for the sodium models of CONTAIN-LMR to be implemented into MELCOR 2.1. In the past year, the implementation included two separate sodium properties from two different sources. The first source is based on the previous work done by Idaho National Laboratory by modifying MELCOR to include liquid lithium equation of state as a working fluid to model the nuclear fusion safety research. To minimize the impact to MELCOR, the implementation of the fusion safety database (FSD) was done by utilizing the detection of the datamore » input file as a way to invoking the FSD. The FSD methodology has been adapted currently for this work, but it may subject modification as the project continues. The second source uses properties generated for the SIMMER code. Preliminary testing and results from this implementation of sodium properties are given. In this year, the design document for the CONTAIN-LMR sodium models, such as the two condensable option, sodium spray fire, and sodium pool fire is being developed. This design document is intended to serve as a guide for the MELCOR implementation. In addition, CONTAIN-LMR code used was based on the earlier version of CONTAIN code. Many physical models that were developed since this early version of CONTAIN may not be captured by the code. Although CONTAIN 2, which represents the latest development of CONTAIN, contains some sodium specific models, which are not complete, the utilizing CONTAIN 2 with all sodium models implemented from CONTAIN-LMR as a comparison code for MELCOR should be done. This implementation should be completed in early next year, while sodium models from CONTAIN-LMR are being integrated into MELCOR. For testing, CONTAIN decks have been developed for verification and validation use.« less

Reconstruction of the action potential of ventricular myocardial fibres

PubMed Central

Beeler, G. W.; Reuter, H.

1977-01-01

1. A mathematical model of membrane action potentials of mammalian ventricular myocardial fibres is described. The reconstruction model is based as closely as possible on ionic currents which have been measured by the voltage-clamp method. 2. Four individual components of ionic current were formulated mathematically in terms of Hodgkin—Huxley type equations. The model incorporates two voltage- and time-dependent inward currents, the excitatory inward sodium current, iNa, and a secondary or slow inward current, is, primarily carried by calcium ions. A time-independent outward potassium current, iK1, exhibiting inward-going rectification, and a voltage- and time-dependent outward current, ix1, primarily carried by potassium ions, are further elements of the model. 3. The iNa is primarily responsible for the rapid upstroke of the action potential, while the other current components determine the configuration of the plateau of the action potential and the re-polarization phase. The relative importance of inactivation of is and of activation of ix1 for termination of the plateau is evaluated by the model. 4. Experimental phenomena like slow recovery of the sodium system from inactivation, frequency dependence of the action potential duration, all-or-nothing re-polarization, membrane oscillations are adequately described by the model. 5. Possible inadequacies and shortcomings of the model are discussed. PMID:874889

Phorbol 12-myristate 13-acetate down-regulates Na,K-ATPase independent of its protein kinase C site: decrease in basolateral cell surface area.

PubMed Central

Beron, J; Forster, I; Beguin, P; Geering, K; Verrey, F

1997-01-01

The effect of protein kinase C (PKC) stimulation on the pump current (Ip) generated by the Na,K-ATPase was measured in A6 epithelia apically permeabilized with amphotericin B. Phorbol 12-myristate 13-acetate (PMA) produced a decrease in Ip carried by sodium pumps containing the endogenous Xenopus laevis or transfected Bufo marinus alpha 1 subunits (approximately 30% reduction within 25 min, maximum after 40 min) independent of the PKC phosphorylation site (T15A/S16A). In addition to this major effect of PMA, which was independent of the intracellular sodium concentration and was prevented by the PKC inhibitor bisindolylmaleimide GF 109203X (BIM), another BIM-resistant, PKC site-independent decrease was observed when the Ip was measured at low sodium concentrations (total reduction approximately 50% at 5 mM sodium). Using ouabain binding and cell surface biotinylation, stimulation of PKC was shown to reduce surface Na,K-ATPase by 14 to 20% within 25 min. The same treatment stimulated fluid phase endocytosis sevenfold and decreased by 16.5% the basolateral cell surface area measured by transepithelial capacitance measurements. In conclusion, PKC stimulation produces a decrease in sodium pump function which can be attributed, to a large extent, to a withdrawal of sodium pumps from the basolateral cell surface independent of their PKC site. This reduction of the number of sodium pumps is parallel to a decrease in basolateral membrane area. Images PMID:9188092

Effects of stochastic sodium channels on extracellular excitation of myelinated nerve fibers.

PubMed

Mino, Hiroyuki; Grill, Warren M

2002-06-01

The effects of the stochastic gating properties of sodium channels on the extracellular excitation properties of mammalian nerve fibers was determined by computer simulation. To reduce computation time, a hybrid multicompartment cable model including five central nodes of Ranvier containing stochastic sodium channels and 16 flanking nodes containing detenninistic membrane dynamics was developed. The excitation properties of the hybrid cable model were comparable with those of a full stochastic cable model including 21 nodes of Ranvier containing stochastic sodium channels, indicating the validity of the hybrid cable model. The hybrid cable model was used to investigate whether or not the excitation properties of extracellularly activated fibers were influenced by the stochastic gating of sodium channels, including spike latencies, strength-duration (SD), current-distance (IX), and recruitment properties. The stochastic properties of the sodium channels in the hybrid cable model had the greatest impact when considering the temporal dynamics of nerve fibers, i.e., a large variability in latencies, while they did not influence the SD, IX, or recruitment properties as compared with those of the conventional deterministic cable model. These findings suggest that inclusion of stochastic nodes is not important for model-based design of stimulus waveforms for activation of motor nerve fibers. However, in cases where temporal fine structure is important, for example in sensory neural prostheses in the auditory and visual systems, the stochastic properties of the sodium channels may play a key role in the design of stimulus waveforms.

Molecular Weights of Bovine and Porcine Heparin Samples: Comparison of Chromatographic Methods and Results of a Collaborative Survey.

PubMed

Bertini, Sabrina; Risi, Giulia; Guerrini, Marco; Carrick, Kevin; Szajek, Anita Y; Mulloy, Barbara

2017-07-19

In a collaborative study involving six laboratories in the USA, Europe, and India the molecular weight distributions of a panel of heparin sodium samples were determined, in order to compare heparin sodium of bovine intestinal origin with that of bovine lung and porcine intestinal origin. Porcine samples met the current criteria as laid out in the USP Heparin Sodium monograph. Bovine lung heparin samples had consistently lower average molecular weights. Bovine intestinal heparin was variable in molecular weight; some samples fell below the USP limits, some fell within these limits and others fell above the upper limits. These data will inform the establishment of pharmacopeial acceptance criteria for heparin sodium derived from bovine intestinal mucosa. The method for MW determination as described in the USP monograph uses a single, broad standard calibrant to characterize the chromatographic profile of heparin sodium on high-resolution silica-based GPC columns. These columns may be short-lived in some laboratories. Using the panel of samples described above, methods based on the use of robust polymer-based columns have been developed. In addition to the use of the USP's broad standard calibrant for heparin sodium with these columns, a set of conditions have been devised that allow light-scattering detected molecular weight characterization of heparin sodium, giving results that agree well with the monograph method. These findings may facilitate the validation of variant chromatographic methods with some practical advantages over the USP monograph method.

Alpha 1-acid glycoprotein reverses cocaine-induced sodium channel blockade in cardiac myocytes.

PubMed

Ma, Yu-Ling; Peters, Nicholas S; Henry, John A

2006-03-01

Alpha 1-acid glycoprotein (AAG) is an acute phase protein capable of binding basic drugs. This action explains its reversal of sodium channel blockade by drugs such as amitriptyline and quinidine. We report here the reversal of cocaine-induced sodium channel blockade by AAG. The sodium channel blocking property of cocaine is a major mechanism behind cocaine-induced sudden cardiac death, since sodium channels play a key role in the initiation and regulation of the heart beat. Voltage-gated sodium current (I(Na)) was recorded using whole-cell patch-clamp techniques. Guinea-pig cardiac ventricular myocytes were isolated and continuously perfused at room temperature with physiological solutions. At concentrations ranging from 5 to 320 microM cocaine showed a dose-dependent and reversible blockade of I(Na) with an IC50 of 45.9 microM. The addition of equimolar amounts of AAG to cocaine produced almost complete reversal of cocaine's effects, suggesting a single binding site for cocaine on the AAG molecule. With changes of peak I(Na) normalized against control as 1, cocaine at 20 and 40 microM reduced I(Na) to 0.62+/-0.042 (n = 6) and 0.57+/-0.052 (n = 9), respectively, and the addition of an equimolar concentration of AAG reversed I(Na) to 0.86+/-0.022 and 0.91+/-0.060, respectively. AAG reverses cocaine-induced sodium channel blockade in a dose-dependent manner, indicating a therapeutic potential to reverse acute cocaine cardiac toxicity.

Molecular determinants on the insect sodium channel for the specific action of type II pyrethroid insecticides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du Yuzhe; Nomura, Yoshiko; Luo Ningguang

2009-01-15

Pyrethroid insecticides are classified as type I or type II based on their distinct symptomology and effects on sodium channel gating. Structurally, type II pyrethroids possess an {alpha}-cyano group at the phenylbenzyl alcohol position, which is lacking in type I pyrethroids. Both type I and type II pyrethroids inhibit deactivation consequently prolonging the opening of sodium channels. However, type II pyrethroids inhibit the deactivation of sodium channels to a greater extent than type I pyrethroids inducing much slower decaying of tail currents upon repolarization. The molecular basis of a type II-specific action, however, is not known. Here we report themore » identification of a residue G{sup 1111} and two positively charged lysines immediately downstream of G{sup 1111} in the intracellular linker connecting domains II and III of the cockroach sodium channel that are specifically involved in the action of type II pyrethroids, but not in the action of type I pyrethroids. Deletion of G{sup 1111}, a consequence of alternative splicing, reduced the sodium channel sensitivity to type II pyrethroids, but had no effect on channel sensitivity to type I pyrethroids. Interestingly, charge neutralization or charge reversal of two positively charged lysines (Ks) downstream of G{sup 1111} had a similar effect. These results provide the molecular insight into the type II-specific interaction of pyrethroids with the sodium channel at the molecular level.« less